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.
[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 <5 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<0.01). 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<0.001) 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<0.01) than the mean peak rise in the 2nd group and
both were significantly lower (P<0.001) 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<0.001). There was also a significant improvement
(P<0.001) in vitamin A absorption of the 1st group and
insignificant increase in the 2nd group but both groups
remained significantly lower (P<0.001) 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.