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VITAMIN A (RETINOL)



Table of Contents
image Intake of carotenoids and retinol in relation to risk of prostate cancer
image Serologic precursors of cancer. Retinol, carotenoids, and tocopherol and risk of prostate cancer
image Zinc, vitamin A and prostatic cancer
image In vitro studies of human prostatic epithelial cells: Attempts to identify distinguishing features of malignant cells
image Application of molecular epidemiology to lung cancer chemoprevention.
image Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease
image Review: Treatment of primary biliary cirrhosis
image Retinol (Vitamin A) supplements in the elderly
image Dietary carotenoids, vitamins A, C, and E, and advanced age-related macular degeneration. Eye Disease Case-Control Study Group
image Vitamins and metals: Potential dangers for the human being
image Vitamin A concentration in the liver decreases with age in patients with cystic fibrosis.
image Relationship between liver cirrhosis death rate and nutritional factors in 38 countries
image Retinoids and carcinogenesis
image Retinoids in cancer treatment.
image Vitamin A preserves the cytotoxic activity of adriamycin while counteracting its peroxidative effects in human leukemic cells in vitro.
image Linking vitamin A and childhood immunizations
image Effect of early vitamin A supplementation on cell-mediated immunity in infants younger than 6 mo
image Molecular mechanisms of vitamin A action and their relationship to immunity
image Historical overview of nutrition and immunity, with emphasis on vitamin A
image Factors associated with age-related macular degeneration. An analysis of data from the first National Health and Nutrition Examination Survey.
image Antioxidant status and lipid peroxidation in hereditary haemochromatosis.
image Chemoprevention of oral leukoplakia and chronic esophagitis in an area of high incidence of oral and esophageal cancer.
image [The role of platelets in the protective effect of a combination of vitamins A, E, C and P in thrombinemia]
image Vitamin A and carotene values of institutionalized mentally retarded subjects with and without Down's syndrome.
image Nutrient intake and food use in an Ojibwa-Cree community in Northern Ontario assessed by 24h dietary recall
image [Patients with type-II diabetes mellitus and neuropathy have nodeficiency of vitamins A, E, beta-carotene, B1, B2, B6, B12 and folic acid]
image Malnutrition in geriatric patients: diagnostic and prognostic significance of nutritional parameters.
image The age-associated decline in immune function of healthy individuals is not related to changes in plasma concentrations of beta-carotene, retinol, alpha-tocopherol or zinc
image [The effect of vitamin A and Astragalus on the splenic T lymphocyte-CFU of burned mice]
image Randomised comparison of fluorouracil, epidoxorubicin and methotrexate (FEMTX) plus supportive care with supportive care alone in patients with non-resectable gastric cancer.
image Critical reappraisal of vitamins and trace minerals in nutritional support of cancer patients.
image Vitamin A, a useful biochemical modulator capable of preventing intestinal damage during methotrexate treatment.
image Hyperthermia, radiation carcinogenesis and the protective potential of vitamin A and N-acetylcysteine
image Immune suppression: therapeutic alterations
image Effects of vitamins A, C, and E on aflatoxin Bsub 1-induced mutagenesis in Salmonella typhimurium TA-98 and TA-100
image Effect of vitamin A supplementation on lectin-induced diarrhoea and bacterial translocation in rats
image Increased translocation of Escherichia coli and development of arthritis in vitamin A-deficient rats
image Gastrointestinal infections in children
image Intestinal malabsorption presenting with night blindness
image Etiology of acute lower respiratory tract infection in children from Alabang, Metro Manila
image Effect of vitamin A in enteral formulae for burned guinea-pigs
image Vitamin A supplementation improves macrophage function and bacterial clearance during experimental salmonella infection
image Inhibition by retinoic acid of multiplication of virulent tubercle bacilli in cultured human macrophages
image Corneal ulceration, measles, and childhood blindness in Tanzania
image Impact of vitamin A supplementation on childhood mortality. A randomised controlled community trial
image Impaired blood clearance of bacteria and phagocytic activity in vitamin A-deficient rats (41999)
image Chronic salmonella septicemia and malabsorption of vitamin A
image Retinol level in patients with psoriasis during treatment with B group vitamins, a bacterial polysaccharide (pyrogenal) and methotrexate (Russian)
image Socioeconomic status and lung cancer incidence in men in The Netherlands: Is there a role for occupational exposure?
image Asthma but not smoking-related airflow limitation is associated with a high fat diet in men: Results from the population study 'Men born in 1914'
image Diminished production of malondialdehyde after carotid artery surgery as a result of vitamin administration
image Effect of supplemental vitamin A on colon anastomotic healing in rats given preoperative irradiation
image Nutritional status and cognitive functioning in a normally aging sample: a 6-y reassessment.
image Antioxidant status of hypercholesterolemic patients treated with LDL apheresis
image Diet and risk of esophageal cancer by histologic type in a low-risk Group
image New agents for cancer chemoprevention
image Metabolism of vitamin A in inflammatory bowel disease
image Vitamin status in patients with inflammatory bowel disease
image Zinc and vitamin A deficiency in patients with Crohn's disease is correlated with activity but not with localization or extent of the disease
image Antioxidants, Helicobacter pylori and stomach cancer in Venezuela.
image Vitamins as therapy in the 1990s
image Association of esophageal cytological abnormalities with vitamin and lipotrope deficiencies in populations at risk for esophageal cancer



Nutrient intake and food use in an Ojibwa-Cree community in Northern Ontario assessed by 24h dietary recall

Nutrition Research (USA), 1997, 17/4 (603-618)

As part of a diabetes prevention program in a remote Ojibwa-Cree community in Northern Ontario, 72% of residents >9y of age (729/1019) underwent an oral glucose tolerance test; >98% (718/729) of participants provided a complete 24h dietary recall. Their diet was typical of that for aboriginal North American populations undergoing rapid cultural change, being high in saturated fat (similar13% energy), cholesterol and simple sugars (similar22% energy), low in dietary fibre (11g/d) and nigh in glycaemic index (similar90). There were high prevalences of inadequate intakes of vitamin A (77%), calcium (58%), vitamin C (40%) and folate (37%). Adolescents aged 10-19y consumed more simple sugars and less protein than adults aged >49y and ate more potato chips, flied potatoes, hamburger, pizza, soft drinks and table sugar. Adults >49y retained more traditional eating habits, using more bannock (fried bread) and wild meats than younger individuals. Interventions to prevent diabetes in the community should include culturally appropriate and effective ways to improve the nutritional adequacy of the diet, reduce fat intake and increase the use of less refined carbohydrate foods.

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[Patients with type-II diabetes mellitus and neuropathy have nodeficiency of vitamins A, E, beta-carotene, B1, B2, B6, B12 and folic acid]

Med Klin (GERMANY) Aug 15 1993, 88 (8) p453-7

The present study was aimed to determine the vitamin status of vitamins A, E, beta-carotene, B1, B2, B6, B12 and folate in plasma using HPLC and vitamins B1, B2 and B6 in erythrocytes using the apoenzyme stimulation test with the Cobas-Bio analyzer in 29 elderly type II diabetic women with (G1: n = 17, age: 68.6 +/- 3.2 years) and without (G2: n = 12, age: 71.8 +/- 2.7 years) diabetic polyneuropathy. The basic parameters as age, hemoglobin A1c, fructosamine and duration of the disease did not differ in both groups. Furthermore, retinopathy was assessed with fundoscopy and nephropathy with creatinine clearance. The creatinine clearance (G1: 50.6 +/- 3.4 vs. G2: 63.6 +/- 3.7 ml/min, 2p < 0.025) and the percentage of retinopathy (G1: 76.5% vs. G2: 16.7%, 2p = 0.002) were different indicating that G1 had significantly more severe late complications than G2. Current plasma levels of all measured vitamins (A, E, beta-carotene, B1, B2, B6, B12 and folate) and the status of B1, B2 and B6 in erythrocytes did not vary between the two groups (2p > 0.1). In summary, we found a lack of association between the actual vitamin condition in plasma and erythrocytes and diabetic neuropathy.



Malnutrition in geriatric patients: diagnostic and prognostic significance of nutritional parameters.

Ann Nutr Metab (SWITZERLAND) 1992, 36 (2) p97-112

Nutritional status was assessed in 300 geriatric patients aged 75 years or more using clinical, anthropometric, biochemical and immunologic methods. Relations between different assessment methods and their prognostic significance with regard to 18-month mortality were examined. For biochemical variables 10% (prealbumin, vitamin B6) to 37% (vitamins A and C) were below conventional limits. In 44% of the patients lymphocytes were diminished. 44% were anergic. Judgement of nutritional status by clinical impression resulted in 22% being deemed undernourished. Clinical diagnosis of undernutrition was associated with low anthropometric measurements (p less than 0.05 for all parameters) and a high prevalence of low biochemical values (p less than 0.05 for albumin, prealbumin, transferrin, vitamin A, vitamin B1). The mean values of all anthropometric variables, plasma proteins, vitamins A and C were significantly lower in patients who died within the following 18 months compared to survivors. The greatest prognostic significance was related to the clinical diagnosis of malnutrition. We conclude that clinical assessment is useful for the evaluation of nutritional status in geriatric patients and the best of numerous nutritional parameters to estimate risk of long-term mortality.



The age-associated decline in immune function of healthy individuals is not related to changes in plasma concentrations of beta-carotene, retinol, alpha-tocopherol or zinc

Mechanisms of Ageing and Development (Ireland), 1997, 94/1-3 (55-69)

The decline in the lymphoproliferative response to mitogenic stimuli shows marked heterogeneity in elderly individuals. Adequate nutriture is required for optimal immune function, yet nutritional status may be compromised in the elderly. To address whether this variation in the proliferative response of elderly individuals is related to their nutritional status, we studied 61 elderly (80.5 plus or minus 5.7 year-old) and 27 young (27.3 plus or minus 3.8 year-old) individuals participating in an ongoing assessment of their immune response to influenza vaccine. Ambulatory elderly individuals were recruited from five different retirement communities and were in good health upon enrollment in the study. Thirty-three percent of young and 54% of elderly subjects reported consuming micronutrient supplements daily during the study. Plasma and peripheral blood mononuclear cells (PBMC) were isolated from fasting individuals twice, 4-6 weeks apart. At both times, proliferative responses to the mitogens phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM) were significantly lower (P < 0.004) in the elderly compared to the young. However, at both times, elderly participants had plasma concentrations of beta-carotene, retinol, alpha-tocopherol and zinc that were either significantly greater than, or equal to, those of young subjects. No significant correlations between plasma concentrations of beta-carotene, retinol, alpha-tocopherol and zinc and level of proliferative responses to each stimuli were observed in elderly individuals at either time. Thus, the heterogeneity in the proliferative response to mitogenic stimuli exhibited by a healthy elderly population cannot be attributed to differences in these nutritional parameters.



[The effect of vitamin A and Astragalus on the splenic T lymphocyte-CFU of burned mice]

Chung Hua Cheng Hsing Shao Shang Wai Ko Tsa Chih (CHINA) Jun 1989

In present study the effects of vitamin A and Astargalus on the splenic TL-CFU of mice were studied by means of T-lymphocytes colony formation in semi-solid culture in vitro and incorporation of 3H-TdR. Marked reduction of the responsive reaction of TL-CFU and T-lymphocyte transformation were found. The TL-CFU of the experimentally burned mice untreated with vitamin A (i.e. group 1) were significantly inhibited (p less than 0.005) in comparison with the unburned control group (i.e. group 4). And the TL-CFU of the experimentally burned mice treated with vitamin A (i.e. group 3) increased significantly (p less than 0.005) in comparison with group 1. Incorporation of 3H-TbR showed that vitamin A might accelerate the proliferation of the TL-CFU of the burned mice. It means that vitamin A might be regarded as an effective agent for the reversal of the inhibition of cell-mediated immunity in post-burned state, whether Ahstragalus plays a role in regulating immune inhibition needs further investigation.



Randomised comparison of fluorouracil, epidoxorubicin and methotrexate (FEMTX) plus supportive care with supportive care alone in patients with non-resectable gastric cancer.

Br J Cancer. 1995 Mar. 71(3). P 587-91

A phase III randomised study, comparing treatment with fluorouracil, epidoxorubicin and methotrexate (FEMTX) with the best supportive care, was conducted in patients with unresectable or metastatic gastric cancer. During the period from July 1986 to June 1992, 41 patients were randomised to receive FEMTX or best supportive care. MTX was given in a dose of 1500 mg m-2 intravenously (i.v.) followed after 1 h by 5-FU 1500 mg m-2 i.v. on day 1; leucovorin rescue was started after 24 h (30 mg orally every 6 h for 48 h) and epidoxorubicin 60 mg m-2 i.v. was administered on day 15. In addition both groups received tablets containing vitamins A and E. Response rates for FEMTX were as follows: complete response (CR), 19% (4/21); partial response (PR), 10% (2/21); no change (NC), 33% (7/21); and progressive disease (PD), 24% (5/21). Response rates in the control group were: NC, 20% (4/20); and PD, 80% (16/20). Increased pain was observed in one patient in the treated group and in 11 patients in the control group within the first 2 months. WHO grade III/IV toxicity in the chemotherapy group was as follows: nausea/vomiting 40%, diarrhoea 10%, stomatitis 15%, leucopenia 50% and thrombocytopenia 10%. One possible treatment-related death was due to sepsis. The median time to progression in the FEMTX group was 5.4 months [95% confidence interval (CI) 3.1-11.7 months], but only 1.7 months in the control group (95% CI 1.2-2.7 months) (P = 0.0013). Similarly, the FEMTX group displayed significantly (P = 0.0006) prolonged survival compared with the control group, i.e. median survival 12.3 months (95% CI 7.1-15.6 months) vs 3.1 months (95% CI 1.6-4.6 months). In conclusion, FEMTX combined with vitamin A and E is a fairly well-tolerated treatment, giving a response rate of 29% in patients with advanced gastric cancer, and also prolonging patients' survival. It can be used as a reference treatment in testing new investigational combinations.



Critical reappraisal of vitamins and trace minerals in nutritional support of cancer patients.

Support Care Cancer. 1993 Nov. 1(6). P 295-7

The potential of a high intake of fresh fruits and vegetables in cancer prevention is well established. Epidemiological studies support carotene, vitamins A, C, E and selenium as the active compounds. Antioxidant properties and direct effects (e.g. inhibition of N-nitrosamine formation or cell-to-cell interactions) are invoked. The role of other trace elements is less clear. The modulation of immune function by vitamins and trace elements remains important and affects survival. In established cancers, the site-specific differences in the diet/cancer relation require appropriate dietary changes, e.g. low fat (20% by energy) in breast cancer, or high vegetable or fruit intake in lung cancer. Single high-dose supplements (e.g. vitamin C) have proved to have no curative or life-prolonging effect. Chemotherapy and radiation increase the requirements for antioxidant compounds. Supplementation can diminish the damage induced by peroxidation. Carefully planned and monitored trials that establish the optimal intake of micronutrients as adjuvants in cancer patients are required.



Vitamin A, a useful biochemical modulator capable of preventing intestinal damage during methotrexate treatment.

Pharmacol Toxicol. 1993 Aug. 73(2). P 69-74

The effects of vitamin A on methotrexate treatment of mice inoculated with L1210 leukaemia cells or sarcoma 180 cells were studied. The small intestine of tumour transplanted mice was severely damaged after methotrexate treatment. Coadministration of vitamin A with methotrexate protected the small intestine from methotrexate-induced damage. The protective effect of vitamin A was histologically and biochemically demonstrated. Further, coadministration of vitamin A did not inhibit in vivo antitumour activity of methotrexate. Thus, biochemical modulation used to prevent methotrexate-induced malabsorption by vitamin A coadministration will be of great use in methotrexate cancer chemotherapy.



Hyperthermia, radiation carcinogenesis and the protective potential of vitamin A and N-acetylcysteine

Journal of Cancer Research and Clinical Oncology (Germany), 1996, 122/6 (343-350)

The in vivo carcinogenic risk of hyperthermia, alone or in combination with irradiation, and the anti-carcinogenic potential of vitamin A and N-acetylcysteine (AcCys) were investigated. Starting 1 month before treatment, 160 rats were divided into four diet groups: no additives, vitamin A-enriched diet, AcCys and the combination vitamin A+ AcCys. In 10 animals per diet group, the hind leg was treated with either X-irradiation alone (16 Gy), hyperthermia alone (60 min at 43degreeC), hyperthermia 5 h prior to irradiation or hyperthermia 5 h after irradiation. Animals were observed for 2 years after treatment with regard to the development of tumours either inside or outside the treated volume. After 16 Gy alone 12 plus or minus 5% of the animals developed a tumour. Tumour incidence increased to 37 plus or minus 9% (borderline significance P = 0.07 versus treatment with X-rays alone) when hyperthermia was applied prior to X-rays, and to 24 plus or minus 8% (NS) with hyperthermia after irradiation. The relative risk ratio (RRR) for tumour induction was increased to 2.4 by hyperthermia if combined with X-irradiation. Pathological characterization of induced tumours showed that these were of the fibrosarcoma, osteosarcoma and carcinoma type. Vitamin A alone or in combination with AcCys slightly protected against the induction of tumours by X-rays without or with hyperthermia (RRR of 0.4). However, morphological changes such as lipid accumulation in hepatocytes and damage to the parenchyma were noticed in livers from all animals that were given a vitamin-A-enriched diet (P < 0.0001). Data from the present and past reports show that hyperthermia alone is not carcinogenic, but that it may increase radiation carcinogenesis. Treatment temperature and time of exposure to heat in addition to the radiation dose applied are important factors in the carcinogenic process. The enhancement of radiation carcinogenesis seems to occur independently of the sequence and time interval between irradiation and hyperthermia. However, not all data are consistent with this interpretation.



Immune suppression: therapeutic alterations

Principles of Cancer Biotherapy, p. 93-162, 1987

The multifactorial basis of cancer-associated immune suppression and the therapeutic strategies attempted for its amelioration are reviewed. The discussion of therapy of immune suppression is limited to biological response modifiers, both biological and chemical, that have been administered to restore depressed immunity or to prevent the deterioration of immune competence due to surgery, radiation therapy, or chemotherapy. Topics include in vivo and in vitro methods for assessment of immune competence, the multifactorial basis of immunodeficiency in cancer patients (pts), immunosuppression and tumor-cell burden, prognostic implications of immunosuppression, perioperative immunosuppression, radiotherapy- and chemotherapy-induced immunosuppression, immune status of pts in clinical remission, and treatment of cancer- and therapy-associated immunodeficiency. A simplified explanation for the immunosuppression of cancer is that products released from malignant cells lead to (a) activation of suppressor cells, (b) impaired effector cell production and survival, and (c) direct inhibition of effector cell function. Most immunotherapeutic approaches for the treatment of immunosuppressed cancer pts have been disappointing. However, two promising trials with levamisole for postoperative pts with colon cancer and malignant melanoma suggest a possible adjuvant role for this drug in these diseases. Studies with levamisole, thymosin fraction 5, thymosin alpha-1, bestatin, and vitamin A have suggested that various immunorestorative agents could ameliorate radiotherapy-induced depression of T-cell numbers or functions, or accelerate the reconstitution of immunity following radiotherapy. There are only very limited data concerning the prevention of chemotherapy-induced immunosuppression.



Effects of vitamins A, C, and E on aflatoxin Bsub 1-induced mutagenesis in Salmonella typhimurium TA-98 and TA-100

TERATOG. CARCINOG. MUTAG. (USA), 1985, 5/1 (29-40)

The effects of retinoids (vitamin A analogs) and vitamins C and E on the aflatoxin Bsub 1-(AFBsub 1)-induced mutagenesis in Salmonella typhimurium TA-98 and TA-100 were investigated. The bioassay was performed under conditions that permitted the effects of vitamins on carcinogen metabolism to be assessed separately from effects on the expression of the mutated bacterial cell. Both retinoic acid and retinol inhibited (up to 50%) AFBsub 1-induced mutagenesis in S. typhimurium TA-98, but only retinol inhibited (up to 75%) mutagenesis in TA-100. Retinoic acid inhibition of mutagenesis in S. typhimurium TA-98 was pronounced over a wide concentration range (i.e., 2 x 10sup -sup 1sup 0 to 2 x 10sup -sup 8 M); however, at the higher concentrations (i.e., 2 x 10sup -sup 8 to 2 x 10sup -sup 6 M range) the predominant effect was the inhibition of the metabolism of AFBsub 1 to its mutagenic metabolites. Vitamin E was more potent in inhibiting the expression of AFBsub 1-induced mutagenesis than vitamin C. However, the major inhibitory effects of vitamin E were related to the metabolism of AFBsub 1, whereas vitamin C was inhibitory at both metabolic and the post-metabolic levels of the AFBsub 1 mutagenesis assay. The results of these investigations suggest that vitamins A, C, or E inhibit both AFBsub 1 metabolism to its mutagenic metabolites as well as the expression of AFBsub 1-induced mutated bacterial cells.



Effect of vitamin A supplementation on lectin-induced diarrhoea and bacterial translocation in rats

Nutrition Research (USA), 1996, 16/3 (459-465)

In a rat model of lectin-induced diarrhoea with translocation of enteric bacteria into mesenteric lymph nodes we evaluated the role of prior vitamin A supplementation in correcting diarrhoea and bacterial translocation. Although intraperitoneal vitamin A palmitate injection (900 microg retinol equivalents twice a week for 5 weeks) substantially increased liver retinol concentration (154.83 plus or minus 23.57 vs 56.65 plus or minus 39.92 microg/g, p< .01), it had no significant effect on faecal wet weight (2.64 plus or minus 1.21 vs 2.86 plus or minus 1.06 g/d), body weight loss (-36.7 plus or minus 16.7 vs -36.5 plus or minus 8.6 g/per 10 days) or rate of translocation (83% vs 100% positive) in supplemented rats compared to unsupplemented rats. However, the mean bacterial count in mesenteric lymph nodes was significantly reduced in vitamin A supplemented group (log colony forming units/g:3.53 plus or minus 0.77 vs 4.03 plus or minus 0.86, p < .05). These findings suggest that vitamin A supplementation did not prevent diarrhoea and weight loss but reduced the severity of intestinal bacterial translocation to mesenteric lymph nodes in red kidney bean-induced diarrhoea and malabsorption. These results are compatible with the demonstrated effect of vitamin A supplementation in reducing childhood mortality in developing countries but with no effect on overall diarrhoea morbidity.



Increased translocation of Escherichia coli and development of arthritis in vitamin A-deficient rats

Infection and Immunity (USA), 1995, 63/8 (3062-3068)

We studied the immune response and the colonization pattern in vitamin A- deficient rats that were colonized with the Escherichia coli O6 K13 pomp 21 strain, which is genetically manipulated to produce ovalbumin and to be resistant to ampicillin. In the vitamin A-deficient rats, the number of bacteria per gram of feces was about five times higher than in the paired fed control rats 4 weeks after colonization. In the control rats, the colon and the lower part of the ileum were colonized, while in the vitamin A-deficient rats all parts of the small intestine, as well as the colon, were heavily inhabited by bacteria. Furthermore, in 75% of the vitamin A-deficient rats, the E. coli bacteria were found in the mesenteric lymph nodes, and in 50% of the rats E. coli were found in the kidneys. These animals also developed severe arthritis. The levels of serum immunoglobulin G (IgG), IgM, IgE, and biliary IgA antibodies against the bacterial antigens were significantly higher in the vitamin A-deficient rats than in the control rats. The number of IgA-producing cells in the lamina propria of the small intestine was significantly lower in the vitamin A-deficient rats than in the control rats; however, there was an increase in the number of CD8+ cells and transforming growth factor beta-producing cells in the lamina propria of the vitamin A- deficient rats. Disturbances in T-cell function were demonstrated, since spleen cells from the vitamin A-deficient rats produced more gamma interferon and interleukin-2 in vitro than control spleen cells. In summary, vitamin A deficiency led to a decrease in the ability to control the localization of intestinal bacteria and an increase in translocation, which was followed by development of arthritis regardless of substantial levels of antibacterial antibodies. The bacterial invasion made the animals hyperresponsive to the bacterial antigens, despite the fact that vitamin A deficiency is normally associated with suppressed antibody production, as previously shown by us and others.



Gastrointestinal infections in children

CURR. OPIN. GASTROENTEROL. (United Kingdom), 1994, 10/1 (88-97)

Gastrointestinal infections are common and important in infants and young children, particularly where poor hygiene and living conditions allow the spread of infectious agents. With increasing information about microorganisms that cause these infections and improved methods to detect them, many episodes that were once undiagnosed can now be attributed to previously unrecognized viruses, bacteria, and other pathogens. These advances facilitate better management and will permit more effective control and preventive strategies. This review highlights some recent reports about enterovirulent classes of Escherichia coli, including E. coli O157:H7, which causes the hemolytic-uremic syndrome and hemorrhagic colitis; Campylobacter species and a new Campylobacter-like organism (Arcobacterbutzlerlli Helicobacter pylori; Aeromonas species; and rotavirus. Important new information about intestinal parasites, including Giardia and Cryptosporidium, has emerged that should prove of practical use in diagnosis and management in places where these parasites are prevalent in children, particularly in parts of the world where HIV infection has become established. A newly described organism, so far called coccidian-like or cyanobacterium-like body, has been found in patients with prolonged diarrhea (including travelers and expatriate residents) in several countries; the name Cyclospora cayetanensis has been proposed for this organism. This year's review concludes with a short commentary on some recent reports about risk factors that predispose children to gastrointestinal infections, eg, nutritional status, domestic hygiene, maternal hygiene behavior, and young children gathered in communal facilities like day care centers. Immune function status is also important, and deficiencies of single nutrients such as vitamin A, pyridoxine, folic acid, iron, and zinc may also play a role.



Intestinal malabsorption presenting with night blindness

BR. J. CLIN. PRACT. (United Kingdom), 1993, 47/5 (275-276)

Night blindness from vitamin A deficiency was observed in a patient with intestinal malabsorption, which in turn was attributable to duodenal diverticulosis and bacterial growth. Monthly supplementation with vitamin A and correction of bacterial overgrowth with tetracycline resulted in a normalisation of plasma retinol levels and resolution of the night blindness.



Etiology of acute lower respiratory tract infection in children from Alabang, Metro Manila

REV. INFECT. DIS. (USA), 1990, 12/SUPPL. 8 (S929-S939)

The etiology of acute lower respiratory tract infection (ALRI) was identified in 235 (43.8%) of 537 hospitalized children &lt5 years of age. Clinical evidence of measles was found in 258 (48.0%) patients, of whom 59 had a second viral infection. A viral agent was identified in an additional 121 patients, so that a total of 379 (70.6%) had viral infections. After measles, respiratory syncytial virus was the most common respiratory virus. Bacteremia was noted in 72 children (13.4%), occurring as frequently in children with measles (14.8%) as in those without (12.1%); Haemophilus influenzae and Salmonella typhi were predominant in the former, and H. influenzae, Staphylococcus aureus, and Streptococcus pneumoniae were prominent in the latter. The presence of bacterial antigen in urine was not helpful in identifying bacterial infection. Extrapulmonary and intrapleural complications, concomitant measles, complicated ALRI, female gender, and malnutrition were associated with increased mortality among children with ALRI. The importance of measles immunization, vitamin A supplementation for alleviation of defects associated with malnutrition, and timely antimicrobial therapy is emphasized.



Effect of vitamin A in enteral formulae for burned guinea-pigs

BURNS (United Kingdom), 1990, 16/4 (265-272)

A burned guinea-pig model (30 per cent body surface area) was used to study the effects of dietary vitamin A. Sixty-five female guinea-pigs were infused enterally via gastrostomy feeding tubes with identical formulae (175 kcal/ kg/day, 20 per cent of calories as protein) containing varying amounts of vitamin A. Groups I, II, III, and IV received formulae containing 0, 10 000 iu (approximately equivalent to the quinea-pigs' RDAe), 50 000 iu (5 x RDA) and 250 000 iu (25 x RDA) of vitamin A per litre, respectively. After 14 days of tube feeding, the animals were killed. Group I animals had evidence of vitamin A deficiency including low haemoglobin levels, lower red blood cell counts and lower caecal mucosal weight. Findings of hypervitaminosis A were observed only in animals given the highest dose of vitamin A (25 x RDA). These were elevated serum alkaline phosphatase and complement C3 levels and enlarged adrenal glands. Group IV also showed defective cell-mediated immunity as reflected by reduced delayed cutaneous response to dinitrofluorobenzene. In a second experiment groups I, II, III and IV were given formulas containing 0,1 x RDA, 5 x RDA, and 10 x RDA of vitamin A respectively for 14 days. Through postburn days 12 to 14 they were injected subcutaneously with 3 x 108 of Staphylococcus aureus once daily. On postburn day 15 the animals were killed and the numbers of viable bacteria at each infection site were counted. No significant differences were observed in viable bacterial numbers between the groups. Serum vitamin A concentration was significantly lower in group I, and there was no sign of hypervitaminosis A in the other groups. These findings suggest that vitamin A is needed following burn injury, and doses of 1 RDA to 10 RDA may be administered safely. However, overdosage (25 x RDA) may be quite harmful.



Vitamin A supplementation improves macrophage function and bacterial clearance during experimental salmonella infection

PROC. SOC. EXP. BIOL. MED. (USA), 1989, 191/1 (47-54)

The effects of additional but nontoxic amounts of vitamin A on susceptibility to salmonella infection was studied by comparing rates of bacterial clearance and phagocytosis. Forty-eight male Lewis rats were divided into a treatment group receiving a total of 6000 units of vitamin A palmitate weekly for 5 weeks and a control group was given an equal volume of saline. After completion of the treatment regimen, one-half from each group were infected intraperitoneally with 105 Salmonella typhimurium; the other half received intraperitoneal injection of saline. At this time no differences in weight gain were noted and all animals were sacrificed within 2 weeks. At 72 hr after bacterial challenge, all saline-treated control animals displayed bacteremia. Cultures of liver and splenic homogenates were positive in 89 and 100% of infected control animals vs 0 and 44% for treated animals during the first week of infection. Kupffer cell, peritoneal, and splenic macrophages of the vitamin A-treated group had greater phagocytic activity than controls as assessed by the percentage of cells ingesting yeast particles and by the number of particles ingested (phagocytic index). These results suggest that vitamin A in moderate amounts may benefit the host's response to infection by enhancing phagocytic cell function.



Inhibition by retinoic acid of multiplication of virulent tubercle bacilli in cultured human macrophages

INFECT. IMMUN. (USA), 1989, 57/3 (840-844)

The immunologically active vitamin retinoic acid (RA) was tested for the ability to increase the resistance of cultured human macrophages (MP) to experimental infection with virulent Mycobacterium tuberculosis Erdman (tubercle bacilli (TB)). It was added to MP in various concentrations and addition regimens. Protection against TB was measured by counting live TB (CFU) in lysates of samples of MP taken at 0, 4, and 7 days after MP infection. RA was protective when added after infection at the pharmacologic concentration of 10-5 M and when added before infection at the physiologic concentration of 10-7 M. The protection lengthened intracellular generation times for TB, occasionally caused bacteriostasis, and regularly kept CFU counts at 7 days (end of the period of infection) 1 to 2 log10 CFU below control values. Significant protection was seen in a series of 16 experiments with MP from seven different donors, but the degree of protection varied considerably. The protection depended partly on and was inversely proportional to concentrations of a serum substitute or autologous serum used as a supplement in the RPMI 1640 MP culture medium. It was strongest at concentrations of serum below 1%. RA at concentrations used in the MP cultures did not inhibit TB in the absence of MP. These results suggest that RA (vitamin A), like vitamin D, may have some immunoprotective role against human tuberculosis, as historically intimated by the regular use of vitamin A- and D-rich cod liver oil for the treatment of tuberculosis before the introduction of modern chemotherapy.



Corneal ulceration, measles, and childhood blindness in Tanzania

BR. J. OPHTHALMOL. (UK), 1987, 71/5 (331-343)

One hundred and thirty Tanzanian children with corneal ulceration were clinically examined to determine the cause of the ulceration. 37% of the ulcers were associated with recent measles infection and 38% of the children had bilateral ulceration. Herpes simplex virus infection was the commonest cause of ulceration in the series, but vitamin A deficiency was the major cause of bilateral ulceration, subsequent blindness, and mortality in this series. Other significant causes of childhood corneal ulceration were the use of traditional eye medicines, confluent measles keratitis, and ophthalmia neonatorum. We discuss the various mechanisms by which measles causes corneal ulceration, and the priorities in prevention and management of corneal ulceration in African children.



Impact of vitamin A supplementation on childhood mortality. A randomised controlled community trial

LANCET (UK), 1986, 1/8491 (1169-1173)

450 villages in northern Sumatra were randomly assigned to either participate in a vitamin A supplementation scheme (n = 229) or serve for 1 year as a control (n = 221). 25,939 preschool children were examined at baseline and again 11 to 13 months later. Capsules containing 200,000 IU vitamin A were distributed to preschool children aged over 1 year by local volunteers 1 to 3 months after baseline enumeration and again 6 months later. Among children aged 12-71 months at baseline, mortality in control villages (75/10 231, 7.3 per 1000) was 49% greater than in those where supplements were given (53/10 919, 4.9 per 1000) (p < 0.05). The impact of vitamin A supplementation seemed to be greater in boys than in girls. These results support earlier observations linking mild vitamin A deficiency to increased mortality and suggest that supplements given to vitamin A deficient populations may decrease mortality by as much as 34%.



Impaired blood clearance of bacteria and phagocytic activity in vitamin A-deficient rats (41999)

PROC. SOC. EXP. BIOL. MED. (USA), 1985, 178/2 (204-208)

The effects of vitamin A deficiency on the functional integrity of the reticuloendothelial system and the phagocytic capacity of circulating polymorphonuclear leukocytes was evaluated in retinoate-cycled vitamin A-deficient rats under conditions such that secondary dietary imbalances were eliminated. Kinetics of blood clearance of 2 x 10sup 7 Escherichia coli injected intravenously was depressed within 8 days of the withdrawal of retinoic acid; all animals were profoundly affected by Day 12 of deficiency. In vitro, the phagocytic activity of polymorphonuclear leukocytes was similarly affected; by Day 12 of deficiency, phagocytic capacity in all deficient animals was less than 40% of the appropriate control values (P&lt0.01). Animals rendered vitamin A deficient by this procedure also displayed marked susceptibility to endogenous bacterial infection, as judged from the proportion of deficient rats that spontaneously developed bacteremia during the later stages of deficiency. These data together demonstrate unequivocally that reticuloendothelial and polymorphonuclear leukocytic functions are impaired in vitamin A deficiency in the absence of other dietary imbalances.



Chronic salmonella septicemia and malabsorption of vitamin A

AM. J. CLIN. NUTR. (USA), 1979, 32/2 (319-324)

Vitamin A absorbtion was studied in two groups of subjects using a vitamin A tolerance test. The first group consisted of 15 patients with chronic salmonella bacteremia associated with Schistosoma manosoni infection and refractory anemia. The second group consisted of 11 patients with active S. mansoni infection associated with anemia but without concurrent salmonellosis. None of the patients had clinical signs of vitamin A deficiency. Ten healthy Egyptians of the same age group with no evidence of any infection served as controls for this absorption test. On admission the mean values of fasting vitamin A and carotene levels in the first group were lower than those in the 2nd group and both levels were significantly lower (P&lt0.001) than the control group mean level. Similarly, the mean peak vitamin A rise after the test dose in the 1st group was significantly lower (P&lt0.01) than the mean peak rise in the 2nd group and both were significantly lower (P&lt0.001) than the control group mean level. After receiving the appropriate therapy, however, the mean fasting vitamin A and carotene levels showed significant increase in both groups (P&lt0.001). There was also a significant improvement (P&lt0.001) in vitamin A absorption of the 1st group and insignificant increase in the 2nd group but both groups remained significantly lower (P&lt0.001) than the control group mean absorption level. The results of this study suggest that chronic salmonellosis may cause gross impairment in vitamin A absorption and may contribute significantly to the wide prevalence of vitamin A deficiency in a given population with borderline dietary intake.



Retinol level in patients with psoriasis during treatment with B group vitamins, a bacterial polysaccharide (pyrogenal) and methotrexate (Russian)

VESTN.DERM.VENER. (USSR), 1975, 51/1 (55-58)

A study of 160 patients with psoriasis revealed a reduction in the content of vitamin A in patients with various forms of psoriasis. During treatment with group B vitamins the best therapeutic effect was observed with vitamins Bsub 5 and Bsub 1sub 5. An increase of vitamin A in the blood was noted during treatment with vitamins Bsub 2 and pellagra preventive factor, whereas vitamins Bsub 1, Bsub 5, Bsub 6, Bsub 9, Bsub 1sub 2 and Bsub 1sub 5 caused a decline of the vitamin A level in the blood. During treatment of psoriatic patients with pyrogenal the content of vitamin A in the blood increased, while methotrexate therapy caused it to decrease. Vitamin A appears to be effective in the treatment of various forms of psoriasis both alone and in combination with methotrexate and vitamins Bsub 1, Bsub 5, Bsub 6, Bsub 9, Bsub 1sub 2 and Bsub 1sub 5.



Socioeconomic status and lung cancer incidence in men in The Netherlands: Is there a role for occupational exposure?

Journal of Epidemiology and Community Health (United Kingdom), 1997, 51/1 (24-29)

Study objective - To evaluate the influence of occupational exposure to carcinogens in explaining the association between socioeconomic status and lung cancer. Design - A prospective cohort study. Data on diet, other lifestyle factors, sociodemographic characteristics and job history were collected by means of a self administered questionnaire. Follow up for incident cancer was established by record linkage with a national pathology register and with regional cancer registries. Setting - Population originating from 204 municipalities in The Netherlands. Participants - These comprised 58,279 men aged 55-69 years in September 1986. After 4.3 years of follow up there were 470 microscopically confirmed incident lung cancer cases with complete data on dietary habits and job history. Measurements and main results - Estimation of occupational exposure to asbestos, paint dust, polycyclic aromatic hydrocarbons, and welding fumes was carried out by two experts, using information on job history from the baseline questionnaire. Socioeconomic status was measured by means of highest attained level of education and two indicators based on occupation. In the initial multivariate analyses of socioeconomic status and lung cancer, adjustment was made for age, smoking habits, intake of vitamin C, betacarotene and retinol, and history of chronic obstructive pulmonary disease or asthma. Additional adjustment for occupational exposure to the four carcinogens mentioned above did not change the inverse association between the level of education and lung cancer risk (initial model: RR highest/lowest level of education = 0.53; 95% CI 0.34,0.82; additional model: RR highest/lowest level of education = 0.53; 95% CI 0.34,0.84). Nor was the association between the two occupation based indicators of socioeconomic status and lung cancer risk influenced by occupational exposure to carcinogens. The effect of occupational exposure on the association between the level of education and lung cancer risk did not differ between ex-smokers and current smokers. Conclusions - Occupational exposure to asbestos, paint dust, polycyclic aromatic hydrocarbons, and welding fumes could not explain the inverse association between socioeconomic status and lung cancer risk. More research which explicitly addresses possible explanations for the association between socioeconomic status and lung cancer risk is needed.