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1.
Curr Dev Nutr ; 6(8): nzac103, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36060219

ABSTRACT

Background: Understanding the influence of participatory video-making on the nutrition-related behavior of video creators may help shape nutrition education interventions. Objectives: This study assessed the perceived value and influence of a participatory video intervention among participants and stakeholders. Methods: A 2018-2019 cluster randomized controlled trial (registered at clinicaltrials.gov as NCT03704649) selected 20 schools (10 intervention, n = 181; 10 control, n = 170) in 1 Ghanaian rural district, enrolled adolescent girls aged 13-16 y, and provided a nutrition curriculum. Each intervention school also participated in 2 series of activities designed to help adolescents plan, film, and screen 2 nutrition-related videos. The Most Significant Change method involved intervention participants and local stakeholders to assess the value and influence of the intervention - a secondary outcome of the trial. Project staff collected 116 stories of change from the adolescents. Stories described shifts in 4 domains: participant, peer, and family behavior, and structural changes in the school. The project team used a selection rubric to identify 14 stories that reflected heightened nutrition literacy. Staff conducted interviews with the 14 adolescents whose stories were selected to elaborate on details and perceived resonance. Finally, local stakeholders assessed the stories to identify the 4 most significant changes of the intervention - 1 per domain. A separate thematic analysis identified emerging patterns of motivation and action across the 14 interviews. Results: The chosen Most Significant Change stories revealed how adolescents found creative solutions to acquire iron-rich foods, encouraged neighbors to eat iron-rich foods, taught their family new agricultural practices, and promoted change in their school canteen. Local stakeholders valued stories that addressed common community nutrition issues in a creative and sustainable way, whereas adolescents prioritized stories that showed a change in health outcomes. Conclusion: Stories of change revealed that the intervention promoted a transformative influence; participants modified their eating habits, lifestyle, and their environment.

2.
Eur J Clin Nutr ; 70(8): 929-34, 2016 08.
Article in English | MEDLINE | ID: mdl-26979989

ABSTRACT

BACKGROUND/OBJECTIVES: Selenium (Se) as part of glutathione peroxidase and iodothyronine deiodinase enzymes influences thyroid metabolism. This study investigated the association of serum Se levels with thyroid metabolism of severely iodine-deficient young children from the Amhara region of Ethiopia. SUBJECTS/METHODS: In a cross-sectional study, Se, thyroid-stimulating hormone, total thyroxin, total triiodothyronine and thyroglobulin in serum of children (N=628) 54-60 months of age from the Amhara region, Ethiopia, were analyzed. In addition, iodine in urine and household salt was analyzed, and the presence of goiter was assessed. RESULTS: The median serum Se concentration was 61.4 µg/l (10.7-290.9 µg/l). Selenium deficiency (serum Se <70 µg/l) was detected in 57.8% (N=349) of the children. The median urinary iodine concentration (UIC) was 9.8 µg/l. The majority (86.6%, N=449) of children had UIC below the recommended value (100 µg/l). In addition, 59.8% (N=310) of children were severely iodine deficient (UIC<20 µg/l). Only 12.7% of salt samples had iodine. Goiter was present in 44.6% (N=280) of the children. Selenium-deficient children had higher serum thyroxin (T4) than children with normal serum Se concentration (P<0.001). CONCLUSIONS: Serum Se was negatively associated with T4 level in young children from the Amhara region of Ethiopia and may endanger the effectiveness of the salt iodization program.


Subject(s)
Iodine/deficiency , Selenium/blood , Thyroxine/blood , Child , Cross-Sectional Studies , Ethiopia/epidemiology , Female , Goiter/blood , Goiter/epidemiology , Goiter/urine , Humans , Iodine/analysis , Iodine/urine , Male , Selenium/deficiency , Sodium Chloride, Dietary/analysis , Thyroid Gland/metabolism
3.
Nature ; 438(7064): 78-81, 2005 Nov 03.
Article in English | MEDLINE | ID: mdl-16267552

ABSTRACT

The Cenozoic collision between the Indian and Asian continents formed the Tibetan plateau, beginning about 70 million years ago. Since this time, at least 1,400 km of convergence has been accommodated by a combination of underthrusting of Indian and Asian lithosphere, crustal shortening, horizontal extrusion and lithospheric delamination. Rocks exposed in the Himalaya show evidence of crustal melting and are thought to have been exhumed by rapid erosion and climatically forced crustal flow. Magnetotelluric data can be used to image subsurface electrical resistivity, a parameter sensitive to the presence of interconnected fluids in the host rock matrix, even at low volume fractions. Here we present magnetotelluric data from the Tibetan-Himalayan orogen from 77 degrees E to 92 degrees E, which show that low resistivity, interpreted as a partially molten layer, is present along at least 1,000 km of the southern margin of the Tibetan plateau. The inferred low viscosity of this layer is consistent with the development of climatically forced crustal flow in Southern Tibet.

4.
J Nutr ; 135(7): 1613-6, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15987837

ABSTRACT

The concept of the nutritional phenotype is proposed as a defined and integrated set of genetic, proteomic, metabolomic, functional, and behavioral factors that, when measured, form the basis for assessment of human nutritional status. The nutritional phenotype integrates the effects of diet on disease/wellness and is the quantitative indication of the paths by which genes and environment exert their effects on health. Advances in technology and in fundamental biological knowledge make it possible to define and measure the nutritional phenotype accurately in a cross section of individuals with various states of health and disease. This growing base of data and knowledge could serve as a resource for all scientific disciplines involved in human health. Nutritional sciences should be a prime mover in making key decisions that include: what environmental inputs (in addition to diet) are needed; what genes/proteins/metabolites should be measured; what end-point phenotypes should be included; and what informatics tools are available to ask nutritionally relevant questions. Nutrition should be the major discipline establishing how the elements of the nutritional phenotype vary as a function of diet. Nutritional sciences should also be instrumental in linking the elements that are responsive to diet with the functional outcomes in organisms that derive from them. As the first step in this initiative, a prioritized list of genomic, proteomic, and metabolomic as well as functional and behavioral measures that defines a practically useful subset of the nutritional phenotype for use in clinical and epidemiological investigations must be developed. From this list, analytic platforms must then be identified that are capable of delivering highly quantitative data on these endpoints. This conceptualization of a nutritional phenotype provides a concrete form and substance to the recognized future of nutritional sciences as a field addressing diet, integrated metabolism, and health.


Subject(s)
Metabolism/physiology , Nutritional Physiological Phenomena/physiology , Phenotype , Diet , Humans , Models, Biological
7.
Soc Sci Med ; 47(5): 645-56, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9690847

ABSTRACT

Researchers have normally considered weaning to be a non-reversible event. To determine the validity of this assumption, we interviewed 36 mothers of toddlers who were living in a poor shanty town of Lima, Peru. Data from 32 women were complete and used in this analysis. Mothers described their beliefs, practices, and decisions about breastfeeding, weaning, and relactation (the reintroduction of breastfeeding after weaning). We recorded attempted weaning events if the mother reported (1) purposefully not breastfeeding with the intention to wean, or (2) carrying out an action that was believed to cause the child to stop breastfeeding. Using a constant comparative approach, references to child-feeding decisions were coded, categorized, and analyzed. All mothers breastfed for at least 12 months; the median duration of breastfeeding was 25 months. There were several different patterns of child-feeding. Thirteen women never attempted to wean their children or had weaned on the first attempt. The majority (n = 19) of women, however, attempted to wean their children - some as early as 3 months of age but relactated between less than 1 day and 3 months later. Factors that influenced feeding decisions were primarily related to maternal and child health, and maternal time commitments. Children were weaned when there was a perceived problem of maternal health or time commitments and child health was not at risk of deterioration. Mothers postponed weaning because of poor child health. The primary reason for relactation was a child's negative reaction to weaning (e.g., incessant crying or refusal to eat). Personalities of the mother and child were important determinants of feeding decisions. These results demonstrate that maternal and child factors jointly influence child-feeding decisions and that these decisions are easily reversed. As relactation is culturally acceptable, health practitioners should consider recommending relactation when children have been prematurely weaned and human milk would improve their nutritional and health status.


Subject(s)
Breast Feeding , Decision Making , Mothers/psychology , Weaning , Adult , Child Welfare , Child, Preschool , Data Collection , Female , Humans , Infant , Maternal Welfare , Peru , Poverty Areas
8.
Am J Clin Nutr ; 66(5): 1102-9, 1997 Nov.
Article in English | MEDLINE | ID: mdl-9356526

ABSTRACT

Although breast-feeding is widely accepted as important for infant health, its benefits during the second year of life have been questioned. We analyzed data from 107 breast-fed and weaned Peruvian children living in a periurban community to determine whether breast milk contributed to improved linear growth between 12 and 15 mo of age. Breast-feeding frequency was self-reported; intakes of complementary foods and animal products were estimated from a food-frequency survey. Multivariate-linear-regression analysis was used to predict the length of the children at 15 mo of age. Determinants of length included length and weight-for-length at 12 mo of age (US National Center for Health Statistics standards), interval between 12- and 15-mo measurements, breast-feeding frequency, incidence of diarrhea, and intakes of complementary and animal-product foods. Complementary foods, animal-product foods, and breast milk all promoted toddlers' linear growth. In subjects with low intakes of animal-product foods, breast-feeding was positively associated (P < 0.05) with linear growth. There was a 0.5-cm/3 mo difference in linear growth between weaned toddlers and children who consumed the average number of feedings of breast milk. Linear growth was also positively associated with intake of animal-product foods in children with low intakes of complementary foods. The negative association between diarrhea and linear growth did not occur in subjects with high complementary-food intakes. When the family's diet is low in quality, breast milk is an especially important source of energy, protein, and accompanying micronutrients in young children. Thus, continued breast-feeding after 1 y of age, in conjunction with feeding of complementary foods, should be encouraged in toddlers living in poor circumstances.


PIP: The contribution of prolonged breast feeding to linear growth at 12-15 months of age was investigated in 107 breast-fed and weaned toddlers from a low-income neighborhood in Lima, Peru. The median duration of breast feeding in this sample was 17.1 months; by 15 months, 46 children had been weaned. The prevalence of stunting (length-for-age score -2 SD below the reference standard) was 17.8% at 12 months and 24.3% at 15 months; no child was wasted. Complementary foods, animal product foods, and breast milk all promoted toddlers' linear growth. In children with low intakes of animal product foods, breast feeding was positively associated with linear growth at 15 months (p 0.05). There was a 0.5 cm/3 months difference in linear growth between weaned toddlers and those who consumed the average number (6.3/day) of breast feeds. Linear growth was further positively associated with intake of animal product foods in children with low intakes of complementary foods. The negative association between diarrhea and linear growth did not occur in children with high intakes of complementary foods. When the household diet is of poor quality, breast feeding is an especially important source of energy, protein, and micronutrients in toddlers and should be continued beyond 12 months of age in conjunction with the provision of complementary foods. Breast milk not only added to the total diet of these young children, but also potentiated the beneficial effects of complementary foods consumed by increasing their growth promotion capacity.


Subject(s)
Breast Feeding , Growth , Infant Food , Infant Nutritional Physiological Phenomena , Meat , Animals , Cattle , Diarrhea, Infantile/epidemiology , Diet Surveys , Humans , Incidence , Infant , Peru , Population Surveillance/methods , Poverty , Regression Analysis , Urban Population
9.
Int J Epidemiol ; 26(2): 349-56, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9169170

ABSTRACT

BACKGROUND: Child feeding recommendations include breastfeeding beyond 12 months, however, some researchers have reported increased rates of malnutrition in breastfed toddlers. A negative association between growth and breast-feeding may reflect reverse causality; that is, the outcome (growth) is a determinant of the predictor (breastfeeding), and not vice versa. We examined this question with data from 134 Peruvian toddlers. METHODS: A linear regression analysis predicted length at the age of 15 months by length at 12 months, study interval, and 12-14.9-month breastfeeding, complementary food intake, and diarrhoeal incidence. This analysis defined the association between breastfeeding and linear growth. To elucidate the direction of the effect between breastfeeding and linear growth, logistic regression was used to predict the probability of weaning by the end of 14 months. Determinants included weight-for-age (W/A) at 12 months, complementary food intake at 9-11.9 months, and change in diarrhoeal incidence between 9 and 14.9 months. RESULTS: There was a significant (P < 0.01) interaction of breastfeeding, diarrhoeal incidence, and complementary food intake on length at 15 months. Increased breastfeeding was associated with a 1.0 cm decrease in length gain when dietary intake was low and diarrhoeal morbidity was high, implying that breastfeeding is harmful. The logistic analysis, however, demonstrated that the risk of weaning decreased only when W/A and dietary intake were low and diarrhoeal morbidity was high. CONCLUSIONS: The negative association between breastfeeding and linear growth reflected reverse causality. Increased breastfeeding did not lead to poor growth; children's poor growth and health led to increased breastfeeding. Children's health must be considered when evaluating the association of breastfeeding with anthropometric outcomes.


PIP: There has been a perplexing finding, in many developing countries, of increased rates of stunting and growth faltering in breast-fed toddlers receiving complementary foods relative to their non-breast-fed counterparts. Longitudinal data on 134 children 12-15 months of age from Lima, Peru, were used to investigate the hypothesis that the negative association between growth and breast feeding reflects reverse causality. The toddlers were participants in a broader persistent diarrhea surveillance survey conducted during 1985-87. 72.9% of children were breast-fed beyond 12 months (median duration, 16.8 months). Anthropometric measurements revealed stunting in 19.4% of toddlers at 12 months and in 29.1% at 15 months. Linear growth between 12 and 15 months had a complex relationship with breast feeding, diarrhea, and dietary factors. Increased breast feeding was associated with a 1.0 cm decrease in length gain between 12 and 15 months when dietary intake was low and diarrheal morbidity was high. However, logistic analysis demonstrated that mothers whose children had low dietary intakes, low weight-for-age, and increased incidence of diarrhea were less likely to wean their infants at 12 and 14 months. This finding that mothers modified their children's feeding practices according to the child's health and growth status supports a reverse causality process in which poor growth is a determinant rather than a result of breast feeding.


Subject(s)
Body Height , Breast Feeding/adverse effects , Developing Countries , Growth Disorders/epidemiology , Infant Food , Weaning , Anthropometry , Body Weight , Diarrhea/epidemiology , Diarrhea/etiology , Female , Growth Disorders/etiology , Humans , Incidence , Infant , Linear Models , Male , Peru/epidemiology , Time Factors
10.
Int Arch Allergy Immunol ; 105(1): 32-7, 1994 Sep.
Article in English | MEDLINE | ID: mdl-8086827

ABSTRACT

Three antigens of Candida albicans were comparatively evaluated to their ability to elicit delayed hypersensitivity (DH) responses in the mouse footpad test, using alloxan-diabetic and normal mice which were primed with heat-killed C. albicans in complete Freund adjuvant. These antigens were: (1) a preparation of sonically disrupted heat-killed cells; (2) a preparation of soluble cytoplasmic material remaining in the supernatant of a broken-cell suspension centrifuged at 100,000 g; (3) a preparation obtained by extraction of pulverized defatted cells with dilute phenol and sodium bicarbonate in water. After separation by polyacrylamide gel electrophoresis, the major components of soluble cytoplasmic material and dilute phenol extract were identified as a 43-kD protein, and glycoproteins of 21, 27 and 38 kD, respectively. Fifty-eight CD-1 outbred mice, which had received a single intravenous injection of alloxan followed by a 28-day rest period, were randomized with normal littermates to distinct experimental groups. Seven days after sensitization, mice were injected with one of the antigens in the right rear footpad and saline in the left rear footpad and the net specific increase in footpad thickness determined 24 and 48 h later. All three antigens elicited significant responses in sensitized normal mice. The responses of sensitized diabetic mice were clearly inferior to those of sensitized normal mice when heat-killed cells and soluble cytoplasmic material were used. Dilute phenol extract elicited equivalent responses at 24 and 48 h in both primed diabetic and normal mice.


Subject(s)
Antigens, Fungal/immunology , Candida albicans/immunology , Diabetes Mellitus, Experimental/immunology , Hypersensitivity, Delayed/immunology , Animals , Diabetes Mellitus, Experimental/metabolism , Female , Glycated Hemoglobin/analysis , Mice , Mice, Inbred Strains
11.
Am J Public Health ; 83(11): 1554-8, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8238677

ABSTRACT

OBJECTIVES: This study was conducted to determine whether poor hygiene practices are owing to difficulty in getting enough water and/or to ignorance of sanitary principles. METHODS: In a water-scarce shantytown in Lima, Peru, we observed in 12-hour periods over 3 consecutive days the amount of water and soap used for personal and domestic activities in 53 families and the frequency with which direct fecal contamination of hands was interrupted by washing. We also surveyed women in a similar shantytown concerning their knowledge of hygiene to ascertain whether noncompliance was owing to ignorance. RESULTS: Three hundred fecal contamination events were registered, of which only 38 (13%) were interrupted by hand washing within 15 minutes. The mean 12-hour per capita amount of water and soap used by the families was low. More than 80% of the water stored by these families had fecal coliforms. Yet the level of knowledge concerning the importance of hand washing and other hygienic practices was high. CONCLUSIONS: In water-scarce areas, sanitary education programs probably will not change hygiene practices. In these areas, an adequate supply of water is essential for good hygiene.


Subject(s)
Hand Disinfection , Health Knowledge, Attitudes, Practice , Poverty Areas , Water Supply/economics , Adolescent , Adult , Child , Child, Preschool , Enterobacteriaceae/isolation & purification , Environmental Microbiology , Feces/microbiology , Female , Humans , Infant , Male , Peru , Regression Analysis , Urban Health , Water Microbiology
12.
J Submicrosc Cytol Pathol ; 25(3): 347-55, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8402534

ABSTRACT

Hen egg-white lysozyme is known to be fungicidal to blastoconidia of Candida albicans under defined in vitro conditions. This lethal action leads to changes in the layering of cell wall and to plasmolysis, caused by unremitting accumulation of wall-like material between the yeast cell wall and cytoplasmic membrane. Here, several methods were applied on ultrathin sections to define the nature of wall-like material: histochemical staining with periodic acid-thiocarbohydrazide-silver proteinate, periodic acid-alkaline bismuth, and phosphotungstic acid at low pH; the localization of the carbohydrate residues with lectin-gold complex; immunocytochemical staining with monospecific antibodies, factor 1 and 6, which recognized major cell wall antigens. The wall-like material was almost uniformly highlighted with periodic acid-thiocarbohydrazide-silver proteinate, factor 1 antibody, concanavalin A-gold and wheat germ agglutinin-ovomucoid-gold, indicating the presence of mannoproteins and chitin. The serotype A-specific epitope recognized by factor 6 antibody was not detected in the wall-like material, although it was demonstrated in the outer cell wall layers after 2 h of exposure to lysozyme.


Subject(s)
Candida albicans/cytology , Muramidase/physiology , Antibodies, Monoclonal/immunology , Antigens/analysis , Antigens/immunology , Candida albicans/physiology , Candida albicans/ultrastructure , Carbohydrates/analysis , Cell Membrane/chemistry , Cell Membrane/ultrastructure , Chitin/analysis , Chitin/immunology , Gold Colloid , Histocytochemistry , Hydrazines , Immunohistochemistry , Membrane Glycoproteins/analysis , Microscopy, Electron , Muramidase/pharmacology , Periodic Acid , Phosphotungstic Acid , Silver Proteins , Wheat Germ Agglutinins
13.
Am J Clin Nutr ; 57(2): 218-23, 1993 Feb.
Article in English | MEDLINE | ID: mdl-7678713

ABSTRACT

To determine the effect of dietary viscosity on energy consumption by young children, 56 Peruvian children 9-20 mo of age with acute diarrhea were randomly assigned to either a liquid or semisolid diet, with or without added amylase to reduce viscosity. Intakes of the study diet, breast milk, and other foods were measured for 2 consecutive d during and again after illness. Total 24-h energy intake (chi +/- SD) during diarrhea, 349.4 +/- 121.8 kJ/kg (83.6 +/- 29.1 kcal/kg) was 18% less than intake after recovery, 428.9 +/- 141.0 kJ/kg (102.6 +/- 33.7), P < 0.001. In the ANOVA breast-fed children consumed significantly less total energy (P = 0.008) and energy from the study diet (P = 0.02) than non-breast-fed children. Breast milk intake did not change with illness. There was no significant relationship between viscosity of the study diet and either total energy intake or intake of energy from the study diet. Energy intake by these children was primarily determined by health status and breast-feeding practice, not by dietary viscosity.


Subject(s)
Amylases/administration & dosage , Diarrhea, Infantile/therapy , Diet , Energy Intake , Infant Food , Milk, Human , Acute Disease , Humans , Infant , Random Allocation , Viscosity
14.
Mycoses ; 36(1-2): 35-41, 1993.
Article in English | MEDLINE | ID: mdl-8316260

ABSTRACT

Studies on the prevalence of tinea pedis, a frequently encountered dermatophytic infection, have been conducted mostly in swimmers although people who regularly practise other types of physical activities may also have a high rate of clinical or subclinical infection. This investigation was undertaken to establish the rate of infection in marathon runners, and to determine the incidence of occult athlete's foot disease in this population. Among samples obtained from 405 individuals, 22% were positive. The rate of infection was highest in the older age groups. The prevalence of infection was 24.2% in men and 6.1% in women. Trichophyton rubrum and Trichophyton mentagrophytes were the two species of dermatophytes most commonly isolated on culture. Occult athlete's foot disease represented 48% of cases with a positive culture. Finally, routine sampling of both feet was confirmed necessary to adequately establish the rate of infection: 26.9% of cases with a positive culture would have been missed by unilateral sampling. Other epidemiological factors were not clearly linked to the prevalence of disease in marathon runners: weight; presence of pet animals; practice of other sports; race and country of origin. In conclusion, we establish that marathon runners represent a population at risk for the occurrence of both clinical and subclinical tinea pedis infection.


Subject(s)
Running , Tinea Pedis/epidemiology , Adolescent , Adult , Female , Humans , Incidence , Male , Middle Aged , Prevalence , Prospective Studies , Tinea Pedis/etiology
15.
APMIS ; 100(11): 967-75, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1472365

ABSTRACT

Susceptible (DBA/2) and resistant (C57BL/6) mice were inoculated intravenously with Candida albicans to evaluate the effect of a four-day prophylaxis with muramyl dipeptide (MDP) on the renal burden of organisms during the first week after infection. In sham-treated DBA/2 mice injected with 8 x 10(4) candida cells, renal CFU (LOG10 +/- SEM) on days 1, 4 and 7 after infection were found to average 5.050 +/- 0.109, 4.882 +/- 0.133 and 5.482 +/- 0.245. In sham-treated C57BL/6 mice injected with 2 x 10(5) candida cells, renal CFU on days 1, 4 and 7 reached only 3.610 +/- 0.118, 3.404 +/- 0.107 and 4.176 +/- 0.580. MDP-treated DBA/2 mice achieved significant reduction in CFU of C. albicans on day 1 (1.3 log units) and day 4 (0.6 log unit), while MDP-treated C57BL/6 mice had significant reduction in CFU of C. albicans only on day 1 (0.6 log unit) after infection. Sham-treated mice of both strains had a 28.6 to 30% increase in kidney weights on day 4 only, a transient change not seen in MDP-treated mice. Histopathological examination on days 8, 15 and 21 after infection revealed a higher incidence of renal papillary necrosis in DBA/2 mice than C57BL/6 mice (approximately 70% vs 10%). The incidence of granulomas and of chronic interstitial inflammation was much higher in MDP-treated mice. We conclude that the genetic makeup of the host influences the potential effectiveness of MDP as a biological response modifier.


Subject(s)
Acetylmuramyl-Alanyl-Isoglutamine/pharmacology , Candidiasis/immunology , Kidney Diseases/immunology , Animals , Candida albicans/growth & development , Candidiasis/microbiology , Candidiasis/pathology , Female , Kidney/immunology , Kidney/microbiology , Kidney/pathology , Kidney Diseases/microbiology , Kidney Diseases/pathology , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Organ Size , Time Factors
16.
J Leukoc Biol ; 50(6): 587-99, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1940612

ABSTRACT

To further define the ultrastructural events associated with the killing of Candida albicans by human neutrophils, four methods were used: (1) the periodate-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining of vicinal-glycol-containing complex carbohydrates; (2) the localization of thermostable immunodeterminants of the yeast cell wall, mannans or mannoproteins, using monospecific antibodies and a protein A-gold complex (monAb-gold); (3) the localization of mannose residues with concanavalin A labeled with gold particles (Con A-gold); (4) the localization of chitin oligomers using wheat germ agglutinin and ovomucoid labeled with gold particles (WGA-gold). The mannan-rich cell wall layers were progressively lost as shown by altered PA-TCH-SP reactivity and a diffuse pattern of staining with Con A-gold and monAb-gold. The de novo appearance of conspicuous amounts of glycogen-like particles near the plasmalemma and in the cell wall was interpreted as evidence of a reparative process of the yeast cell wall. Chitin was seemingly unaltered and readily demonstrated by the WGA-gold in the wall remnants of ghost cells.


Subject(s)
Candida albicans/immunology , Neutrophils/microbiology , Candida albicans/ultrastructure , Cell Membrane/ultrastructure , Cell Wall/ultrastructure , Concanavalin A/metabolism , Humans , Immunohistochemistry , In Vitro Techniques , Microscopy, Electron , Neutrophils/ultrastructure , Phagosomes/microbiology
17.
Trans R Soc Trop Med Hyg ; 85(6): 761-4, 1991.
Article in English | MEDLINE | ID: mdl-1801349

ABSTRACT

The prevalence and symptoms of pinworm infection were determined in a shanty town in Lima, Peru. In 206 families, pinworm infection rates were highest in primary school age children (42%). Approximately one-fourth of pre-school children and secondary school-age children were infected with pinworms. Two examinations detected 74% of patients who were positive after 5 examinations. Symptoms often attributed to pinworm infection, such as perianal itching enuresis, and teeth grinding, occurred in a similar proportion of infected children (15%, 17%, 13%, respectively) and non-infected subjects (11%, 13%, 11%, respectively). Enuresis was more common in primary school-age children with high pinworm egg counts than in their non-infected contemporaries. 52% (28/54) of children under 5 years old became reinfected within 6 months of effective treatment. In a community where water is scarce and hand washing is infrequent, the high rate of perianal itching is probably an important source of faecal-oral contamination. The low morbidity and high reinfection rate make routine treatment of pinworm infection in third world countries a low priority, except when clinically indicated.


Subject(s)
Oxyuriasis/epidemiology , Adolescent , Adult , Albendazole/therapeutic use , Child , Child, Preschool , Feces/parasitology , Humans , Infant , Middle Aged , Oxyuriasis/complications , Parasite Egg Count , Peru/epidemiology , Prevalence , Pruritus/etiology , Risk Factors , Urban Population
18.
Infect Immun ; 59(4): 1312-8, 1991 Apr.
Article in English | MEDLINE | ID: mdl-1706318

ABSTRACT

The fungicidal effect of lysozyme on Candida albicans involves ultrastructural modifications previously described (G. Marquis, S. Montplaisir, S. Garzon, H. Strykowski, and P. Auger, Lab. Invest. 46:627-636, 1982). To further define the action of lysozyme on the yeast cell wall, we used the following: (i) the periodic acid-thiocarbohydrazide-silver proteinate (PA-TCH-SP) method to highlight vicinal-glycol-reactive sites of complex carbohydrates; (ii) a monospecific antiserum and a protein A-gold complex to study the expression of surface factor 4, a major Candida antigen; and (iii) the periodic acid-silver methenamine method to stain cell wall glycoproteins. All Candida cells were found to express surface factor 4 antigen. In normal blastoconidia, surface factor 4 was located in a glycoprotein-rich cell wall layer, underneath radially oriented bundles of filaments which form the outermost wall layer. In lysozyme-treated blastoconidia, this glycoprotein-rich layer was lost and the regular brushlike organization of the outer fibrillogranular layer was disrupted. PA-TCH-SP staining and localization of surface factor 4 antigen demonstrated an altered arrangement of bundles of filaments in the outer wall layers of blastoconidia which were morphologically intact but had abnormal cell wall appearance. Next, there was a reduction in thickness of the outer layer and the expression of surface factor 4 antigen was limited to the cytoplasmic membrane area. Later on, the cell wall was almost uniformly highlighted by PA-TCH-SP staining. These data evinced a highly plastic architecture of the cell wall in C. albicans.


Subject(s)
Antigens, Fungal/analysis , Candida albicans/immunology , Glycoproteins/analysis , Muramidase/pharmacology , Candida albicans/ultrastructure , Cell Wall/drug effects , Cell Wall/immunology , Gold , Staining and Labeling
19.
J Clin Microbiol ; 29(3): 636-7, 1991 Mar.
Article in English | MEDLINE | ID: mdl-2037685

ABSTRACT

Stool microscopy and an enzyme-linked immunosorbent assay (ELISA) for Giardia lamblia antigen detection were compared for detecting G. lamblia in 30 Peruvian infants. Of 1,131 fecal specimens, G. lamblia was detected by ELISA alone in 44, by microscopy alone in 17, and by both methods in 91. In another group of 17 children negative for G. lamblia by stool microscopy, 6 had G. lamblia detected by ELISA or duodenal aspiration: 2 only by ELISA, 1 only by duodenal aspirate examination, and 3 by both examinations. The ELISA is useful for the detection of G. lamblia in fecal specimens but compared to stool microscopy does not significantly increase the detection of cases.


Subject(s)
Antigens, Protozoan/isolation & purification , Giardia/immunology , Giardiasis/diagnosis , Animals , Duodenum/immunology , Duodenum/parasitology , Enzyme-Linked Immunosorbent Assay , Evaluation Studies as Topic , Feces/parasitology , Giardia/isolation & purification , Giardiasis/immunology , Giardiasis/parasitology , Humans , Infant , Infant, Newborn , Peru , Sensitivity and Specificity
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