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Reyes-López M, Ramírez-Rico G, Serrano-Luna J, de la Garza M. Activity of Apo-Lactoferrin on Pathogenic Protozoa. Pharmaceutics 2022; 14:pharmaceutics14081702. [PMID: 36015327 PMCID: PMC9414845 DOI: 10.3390/pharmaceutics14081702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022] Open
Abstract
Parasites and other eventually pathogenic organisms require the ability to adapt to different environmental conditions inside the host to assure survival. Some host proteins have evolved as defense constituents, such as lactoferrin (Lf), which is part of the innate immune system. Lf in its iron-free form (apo-Lf) and its peptides obtained by cleavage with pepsin are microbicides. Parasites confront Lf in mucosae and blood. In this work, the activity of Lf against pathogenic and opportunistic parasites such as Cryptosporidium spp., Eimeria spp., Entamoeba histolytica, Giardia duodenalis, Leishmania spp., Trypanosoma spp., Plasmodium spp., Babesia spp., Toxoplasma gondii, Trichomonas spp., and the free-living but opportunistic pathogens Naegleria fowleri and Acanthamoeba castellani were reviewed. The major effects of Lf could be the inhibition produced by sequestering the iron needed for their survival and the production of oxygen-free radicals to more complicated mechanisms, such as the activation of macrophages to phagocytes with the posterior death of those parasites. Due to the great interest in Lf in the fight against pathogens, it is necessary to understand the exact mechanisms used by this protein to affect their virulence factors and to kill them.
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Abstract
BACKGROUND Infection with the protozoan Entamoeba histolytica is common in low- and middle-income countries, and up to 100,000 people with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission. OBJECTIVES To evaluate antiamoebic drugs for treating amoebic colitis. SEARCH METHODS We searched the available literature up to 22 March 2018. We searched the Cochrane Infectious Diseases Group Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, mRCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and we checked reference lists. SELECTION CRITERIA Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug, for treating adults and children with a diagnosis of amoebic colitis. DATA COLLECTION AND ANALYSIS Two review authors independently assessed the eligibility and methodological quality of trials and extracted and analysed the data. We calculated clinical and parasitological failure rates and rates of relapse and adverse events as risk ratios (RRs) with 95% confidence intervals (CIs), using a random-effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis by using trial quality to assess the robustness of reported results. MAIN RESULTS In total, 41 trials (4999 participants) met the inclusion criteria of this review. In this update, we added four trials to the 37 trials included in the first published review version. Thirty trials were published over 20 years ago. Only one trial used adequate methods of randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used an E histolytica stool antigen test, and two trials used amoebic culture.Tinidazole may be more effective than metronidazole for reducing clinical failure (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials; low-certainty evidence) and is probably associated with fewer adverse events (RR 0.65, 95% CI 0.46 to 0.92; 477 participants, 8 trials; moderate-certainty evidence). Compared with metronidazole, combination therapy may result in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials; low-certainty evidence), but we are uncertain which combination is more effective than another. Evidence is insufficient to allow conclusions regarding the efficacy of other antiamoebic drugs. AUTHORS' CONCLUSIONS Compared with metronidazole, tinidazole may be more effective in reducing clinical failure and may be associated with fewer adverse events. Combination drug therapy may be more effective for reducing parasitological failure compared with metronidazole alone. However, these results are based mostly on small trials conducted over 20 years ago with a variety of poorly defined outcomes. Tests that detect E histolytica more accurately are needed, particularly in countries where concomitant infection with other bacteria and parasites is common.
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Affiliation(s)
- Maria Liza M Gonzales
- University of the Philippines Manila College of Medicine‐Philippine General HospitalDepartment of PediatricsTaft AvenueManilaNational Capital RegionPhilippines1000
| | - Leonila F Dans
- University of the Philippines Manila College of Medicine‐Philippine General HospitalDepartment of PediatricsTaft AvenueManilaNational Capital RegionPhilippines1000
| | - Juliet Sio‐Aguilar
- University of the Philippines Manila College of Medicine‐Philippine General HospitalDepartment of PediatricsTaft AvenueManilaNational Capital RegionPhilippines1000
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Ortíz-Estrada G, Luna-Castro S, Piña-Vázquez C, Samaniego-Barrón L, León-Sicairos N, Serrano-Luna J, de la Garza M. Iron-saturated lactoferrin and pathogenic protozoa: could this protein be an iron source for their parasitic style of life? Future Microbiol 2012; 7:149-64. [PMID: 22191452 DOI: 10.2217/fmb.11.140] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Iron is an essential nutrient for the survival of pathogens inside a host. As a general strategy against microbes, mammals have evolved complex iron-withholding systems for efficiently decreasing the iron accessible to invaders. Pathogens that inhabit the respiratory, intestinal and genitourinary tracts encounter an iron-deficient environment on the mucosal surface, where ferric iron is chelated by lactoferrin, an extracellular glycoprotein of the innate immune system. However, parasitic protozoa have developed several mechanisms to obtain iron from host holo-lactoferrin. Tritrichomonas fetus, Trichomonas vaginalis, Toxoplasma gondii and Entamoeba histolytica express lactoferrin-binding proteins and use holo-lactoferrin as an iron source for growth in vitro; in some species, these binding proteins are immunogenic and, therefore, may serve as potential vaccine targets. Another mechanism to acquire lactoferrin iron has been reported in Leishmania spp. promastigotes, which use a surface reductase to recognize and reduce ferric iron to the accessible ferrous form. Cysteine proteases that cleave lactoferrin have been reported in E. histolytica. This review summarizes the available information on how parasites uptake and use the iron from lactoferrin to survive in hostile host environments.
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Affiliation(s)
- Guillermo Ortíz-Estrada
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN, Apdo. 14-740, México DF 07000, México
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León-Sicairos N, Martínez-Pardo L, Sánchez-Hernández B, de la Garza M, Carrero JC. Oral lactoferrin treatment resolves amoebic intracecal infection in C3H/HeJ mice. Biochem Cell Biol 2012; 90:435-41. [PMID: 22452668 DOI: 10.1139/o2012-008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Entamoeba histolytica is a protozoan parasite that causes amoebiasis, an illness that affects many people around the world. We have previously reported that lactoferrin is able to kill E. histolytica in in vitro cultures. The aim of the present study was to evaluate the therapeutic effect of orally administered bovine lactoferrin in the control of intestinal amoebiasis of susceptible C3H/HeJ mice. The results showed that 20 mg lactoferrin/kg orally administered each day for 1 week was able to eliminate the infection in 63% of the mice, since neither trophozoites nor evidence of epithelial damage and (or) swelling were found in tissue sections of the cecum. The rest of the treated animals (37%) showed a decrease in trophozoite numbers and mucus secreted to the lumen, as compared with untreated and infected mice (p < 0.05). By immunohistochemistry, the profile of secreted cytokines in the cecum revealed that infected but untreated animals showed a mixed Th1/regulatory cytokines profile, whereas the cecum of mice treated (cured) showed a Th2 cytokine profile (IL-4) and expression of the multifunctional IL-6. In addition, cytokines and increasing cecal production of total IgA antibodies were found associated with little inflammation and disease control observed in the cecum of lactoferrin-treated animals. These results suggest that oral administration of lactoferrin can control intestinal amoebic infection probably by killing amoebas or favoring their removal and reestablish the antiinflammatory intestinal environment.
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Affiliation(s)
- Nidia León-Sicairos
- Unidad de Investigación de la Facultad de Medicina, Universidad Autónoma de Sinaloa. Cedros y Sauces, Fraccionamiento Fresnos. Culiacán, Sinaloa, C.P. 80246, México
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Ordaz-Pichardo C, León-Sicairos N, Hernández-Ramírez VI, Talamás-Rohana P, de la Garza M. Effect of bovine lactoferrin in a therapeutic hamster model of hepatic amoebiasis. Biochem Cell Biol 2012; 90:425-34. [PMID: 22332957 DOI: 10.1139/o11-084] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Entamoeba histolytica is the causative agent of amoebiasis, a disease that produces dysentery as a result of the perforation of the large intestine. This parasite often invades other organs, primarily the liver, leading to an amoebic liver abscess (ALA), which can cause death. Metronidazole is the drug of choice for the treatment of ALA; however, it produces toxic side effects in patients. Lactoferrin (Lf) is a glycoprotein of the innate immune response that sequesters iron in the mucosae. Lf possesses immune-regulatory properties, such as antiinflammatory and antioxidant activities. Moreover, the microbicidal activity of apoLf, which lacks bound iron, has been shown. In this study, we evaluated the therapeutic effect of bovine Lf (bLf) against ALA in a model of hepatic amoebiasis in hamsters. Interestingly, hamsters treated intragastrically with Lf (2.5 mg/100 g mass) over a period of 8 days showed no clinical signs of disease and ALA was effectively decreased, with only 0.63% detectable lesion, compared with 63% in untreated animals. Furthermore, liver function and blood cells approached normal levels among those receiving bLf treatment. These results suggest that bLf may aid in the therapy of amoebiasis, likely without producing undesirable effects in patients.
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Affiliation(s)
- Cynthia Ordaz-Pichardo
- Laboratorio de Biología Celular y Productos Naturales, Escuela Nacional de Medicina y Homeopatía, Instituto Politécnico Nacional, Guillermo Massieu Helguera No. 239 Fraccionamiento La Escalera, Ticomán, D.F. 07320, México
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Knoll N, Kuhnt K, Kyallo FM, Kiage-Mokua BN, Jahreis G. High content of long-chain n-3 polyunsaturated fatty acids in red blood cells of Kenyan Maasai despite low dietary intake. Lipids Health Dis 2011; 10:141. [PMID: 21854590 PMCID: PMC3179448 DOI: 10.1186/1476-511x-10-141] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 08/19/2011] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Increasing land restrictions and a reduced livestock-to-human ratio during the 20th century led the Maasai to lead a more sedentary, market-orientated lifestyle. Although plant-derived food nowadays contributes substantially to their diet, dairy products being high in saturated fatty acids (SFA) and low in polyunsaturated fatty acids (PUFA) still are an important energy source. Since reliable data regarding the Maasai diet date back to the 1980s, the study objective was to document current diet practices in a Kenyan Maasai community and to investigate the fatty acid distribution in diet and red blood cells. METHODS A cross-sectional study was conducted among 26 Maasai (20 women, 6 men) from Loodokilani, Kajiado District, Kenya. Food intake was described by the subjects via 24-h recall, and both food and blood samples were analysed. RESULTS Two main foods--milk and ugali--constituted the Maasai diet in this region. A total of 0.9 L of milk and 0.6 kg of ugali were consumed per person and day to yield an energy intake of 7.6 MJ/d per person. A major proportion of ingested food contributing 58.3% to the total dietary energy (en%) was plant-derived, followed by dairy products representing 41.1 en%. Fat consumed (30.5 en%) was high in SFA (63.8%) and low in PUFA (9.2%). Long-chain n-3 PUFA (EPA, DPA and DHA) made up only 0.15% of the ingested fatty acids, but 5.9% of red blood cell fatty acids. CONCLUSION The study indicates the Maasai diet is rich in SFA and low in PUFA. Nevertheless, red blood cells are composed of comparable proportions of long-chain n-3 PUFA to populations consuming higher amounts of this fatty acid group.
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Affiliation(s)
- Nadja Knoll
- Department of Nutritional Physiology, Institute of Nutrition, Friedrich-Schiller-University, Dornburger Str. 24, Jena, Germany
| | - Katrin Kuhnt
- Department of Nutritional Physiology, Institute of Nutrition, Friedrich-Schiller-University, Dornburger Str. 24, Jena, Germany
| | - Florence M Kyallo
- Department of Food Science and Technology, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Beatrice N Kiage-Mokua
- Department of Food Science and Technology, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
| | - Gerhard Jahreis
- Department of Nutritional Physiology, Institute of Nutrition, Friedrich-Schiller-University, Dornburger Str. 24, Jena, Germany
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Abstract
The interaction between nutrition and infection was the subject of important work by several groups in the 1960s. The explosion of knowledge in immunology, including innate immunity, has led to increased understanding of the impact of nutrition on host defence, but much more work needs to be done in this area. In the last decade an increasing volume of work has opened up the previously obscure world of human endogenous flora. This work suggests that the microbiome, the total genetic pool of the microbiota, contributes to the already complex interaction between nutrition and infectious disease. The established concept that nutritional status, host defence and infection all impact on each other now has to be expanded into a multiple interaction, with the microbiota interacting with all three other elements. There is good evidence that the microbiome programmes host defence and drives a metabolome that impacts on energy balance, and indeed on some micronutrients. In turn, host defence shapes the microbiome, and nutritional status, particularly micronutrient status, helps determine several elements of host defence. While interventions in this area are in their infancy, the understanding of interactions that already have an enormous impact on global health is now at a threshold. The present review explores the evidence for these interactions with a view to putting potential interventions into the context of a conceptual framework.
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Figueroa G, Troncoso M, Galeno H, Faundez G. Oral Iron Supplementation and Diarrhoeal Disease in Infants: A Prospective Bacteriological Study. MICROBIAL ECOLOGY IN HEALTH AND DISEASE 2009. [DOI: 10.3109/08910609009140128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- G. Figueroa
- Microbiology Unit, Institute of Nutrition and Food Technology, University of Chile, Casilla 11–138, Santiago, Chile
| | - M. Troncoso
- Microbiology Unit, Institute of Nutrition and Food Technology, University of Chile, Casilla 11–138, Santiago, Chile
| | - H. Galeno
- Microbiology Unit, Institute of Nutrition and Food Technology, University of Chile, Casilla 11–138, Santiago, Chile
| | - G. Faundez
- Microbiology Unit, Institute of Nutrition and Food Technology, University of Chile, Casilla 11–138, Santiago, Chile
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Use and endocytosis of iron-containing proteins by Entamoeba histolytica trophozoites. INFECTION GENETICS AND EVOLUTION 2009; 9:1038-50. [PMID: 19539057 DOI: 10.1016/j.meegid.2009.05.018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Revised: 04/16/2009] [Accepted: 05/19/2009] [Indexed: 11/20/2022]
Abstract
Iron is essential for nearly all organisms; in mammals, it is part of proteins such as haemoglobin, and it is captured by transferrin and lactoferrin. Transferrin is present in serum, and lactoferrin is secreted by the mucosa and by neutrophils at infection sites, as a host iron-withholding response, sequestering iron away from invading microorganisms. Additionally, all cells contain ferritin, which sequesters iron when its intracellular levels are increased, detoxifying and preventing damage. Liver ferritin contains 50% of iron corporal reserves. During evolution, pathogens have evolved diverse strategies to obtain iron from their hosts in order to survive. The protozoan Entamoeba histolytica invades the intestinal mucosa, causing dysentery, and the trophozoites often travel to the liver producing hepatic abscesses; thus, intestine and liver proteins could be important iron supplies for E. histolytica. We found that E. histolytica trophozoites can grow in both ferrous and ferric iron, and that they can use haemoglobin, holo-transferrin, holo-lactoferrin, and ferritin as in vitro iron sources. These proteins supported the amoeba growth throughout consecutive passages, similarly to ferric citrate. By confocal microscopy and immunoblotting, iron-binding proteins were observed specifically bound to the amoeba surface, and they were endocytosed, trafficked through the endosomal/lysosomal route, and degraded by neutral and acidic cysteine-proteases. Transferrin and ferritin were mainly internalized through clathrin-coated vesicles, and holo-lactoferrin was mainly internalized by caveola-like structures. In contrast, apo-lactoferrin bound to membrane lipids and cholesterol, inducing cell death. The results suggest that in vivo trophozoites secrete products that can destroy enterocytes, erythrocytes, and hepatocytes, releasing transferrin, haemoglobin, ferritin, and other iron-containing proteins, which, together with lactoferrin derived from neutrophils and acinar cells, could be used as abundant iron supplies by amoebas.
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Abstract
BACKGROUND Entamoeba histolytica infection is common in developing countries, and up to 100,000 individuals with severe disease die every year. Adequate therapy for amoebic colitis is necessary to reduce the severity of illness, prevent development of complicated disease and extraintestinal spread, and decrease transmission. OBJECTIVES To evaluate antiamoebic drugs for treating amoebic colitis. SEARCH STRATEGY In September 2008, we searched the Cochrane Infectious Diseases Group Specialized Register, CENTRAL (2008, Issue 3), MEDLINE, EMBASE, LILACS, mRCT, and conference proceedings. We contacted individual researchers, organizations, and pharmaceutical companies, and checked reference lists. SELECTION CRITERIA Randomized controlled trials of antiamoebic drugs given alone or in combination, compared with placebo or another antiamoebic drug for treating adults and children diagnosed with amoebic colitis. DATA COLLECTION AND ANALYSIS Two authors independently assessed the eligibility and methodological quality of trials, and extracted and analysed the data. We calculated clinical and parasitological failure rates, relapse, and adverse events as risk ratios (RR) with 95% confidence intervals (CIs), using a random-effects model. We determined statistical heterogeneity and explored possible sources of heterogeneity using subgroup analyses. We carried out sensitivity analysis using trial quality to assess the robustness of the results. MAIN RESULTS Thirty-seven trials, enrolling 4487 participants, met the inclusion criteria. Only one trial used adequate methods for randomization and allocation concealment, was blinded, and analysed all randomized participants. Only one trial used a E. histolytica stool antigen test. Tinidazole reduced clinical failure compared with metronidazole (RR 0.28, 95% CI 0.15 to 0.51; 477 participants, eight trials) and was associated with fewer adverse events. Compared with metronidazole, combination therapy resulted in fewer parasitological failures (RR 0.36, 95% CI 0.15 to 0.86; 720 participants, 3 trials). AUTHORS' CONCLUSIONS Tinidazole is more effective in reducing clinical failure compared with metronidazole and has fewer associated adverse events. Combination drug therapy is more effective in reducing parasitological failure compared with metronidazole alone. However, these results are based on trials with poor methodological quality so there is uncertainty in these conclusions. Further trials of the efficacy of antiamoebic drugs, with better methodological quality, are recommended. More accurate tests to detect E. histolytica are needed, particularly in countries where concomitant infection with other bacteria and parasites is common.
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Affiliation(s)
- Maria Liza M Gonzales
- Department of Pediatrics, College of Medicine-Philippine General Hospital, University of the Philippines, Taft Avenue, Manila, National Capital Region, Philippines, 1000.
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Espinosa A, Perdrizet G, Paz-Y-Miño C G, Lanfranchi R, Phay M. Effects of iron depletion on Entamoeba histolytica alcohol dehydrogenase 2 (EhADH2) and trophozoite growth: implications for antiamoebic therapy. J Antimicrob Chemother 2009; 63:675-8. [PMID: 19218278 DOI: 10.1093/jac/dkp015] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES The purpose of this study was to determine the mechanism by which iron chelation affects the trophozoite survival of Entamoeba histolytica. Fe2+ is a cofactor for E. histolytica alcohol dehydrogenase 2 (EhADH2), an essential bifunctional enzyme [alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH)] in the glycolytic pathway of E. histolytica. METHODS We tested the effects of iron depletion on trophozoite growth, the kinetics of iron binding to EhADH2, and the activities of ADH and ALDH. RESULTS Growth of E. histolytica trophozoites, and ADH and ALDH enzymatic activities were directly inhibited by iron chelation. Kinetics of iron binding to EhADH2 reveals the differential iron affinity of ADH (higher) and ALDH (lower). CONCLUSIONS This study demonstrates that iron chelation interrupts the completion of the fermentative pathway of E. histolytica by removing the metal cofactor indispensable for the structural and functional stability of EhADH2, thus affecting trophozoite survival. We propose that iron-starvation-based strategies could be used to treat amoebiasis.
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Affiliation(s)
- Avelina Espinosa
- Department of Biology, Roger Williams University, One Old Ferry Road, Bristol, RI 02809, USA.
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Lee J, Park SJ, Yong TS. Effect of iron on adherence and cytotoxicity of Entamoeba histolytica to CHO cell monolayers. THE KOREAN JOURNAL OF PARASITOLOGY 2008; 46:37-40. [PMID: 18344676 DOI: 10.3347/kjp.2008.46.1.37] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Iron is an essential element for almost all living organisms. The possible role of iron for growth, adherence and cytotoxicity of Entamoeba histolytica was evaluated in this study. The absence of iron from TYI-S-33 medium stopped amebic growth in vitro. However, iron concentrations in the culture media of 21.4-285.6 microM did not affect the growth of the amebae. Although growth was not retarded at these concentrations, the adhesive abilities of E. histolytica and their cytotoxicities to CHO cell monolayer were correlated with iron concentration. Amebic adhesion to CHO cell monolayers was significantly reduced by low-iron (24.6 +/- 2.1%) compared with 62.7 +/- 2.8 and 63.1 +/- 1.4% of amebae grown in a normal-iron and high-iron media, respectively. E. histolytica cultured in the normal- and high-iron media destroyed 69.1 +/- 4.3% and 72.6 +/- 5.7% of cultured CHO cell monolayers, but amebae grown in the low-iron medium showed a significantly reduced level of cytotoxicity to CHO cells (2.8 +/- 0.2%). Addition of divalent cations other than iron to amebic trophozoites grown in the low-iron medium failed to restore levels of the cytotoxicity. However, when E. histolytica grown in low-iron medium were transferred to normal-iron medium, the amebae showed completely restored cytotoxicity within 7 days. The result suggests that iron is an important factor in the adherence and cytotoxicity of E. histolytica to CHO cell monolayer.
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Affiliation(s)
- Jongweon Lee
- Department of Environmental Medical Biology and Institute of Tropical Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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Long KZ, Rosado JL, Fawzi W. The Comparative Impact of Iron, the B-Complex Vitamins, Vitamins C and E, and Selenium on Diarrheal Pathogen Outcomes Relative to the Impact Produced by Vitamin A and Zinc. Nutr Rev 2008; 65:218-32. [PMID: 17566548 DOI: 10.1111/j.1753-4887.2007.tb00299.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Micronutrient supplementation offers one of the most cost-effective means of improving the health and survival of children in developing countries. However, the effects of supplementation with single micronutrients on diarrhea are not always consistent, and supplementation with multi-micronutrient supplements can have negative effects. These inconsistencies may result from the failure to consider the diverse etiological agents that cause diarrhea and the unique effects each micronutrient has on the immune response to each of these agents. This review examines the separate effects that supplementation with the B-complex vitamins, vitamin C, vitamin E, selenium, and iron have on diarrheal disease-related outcomes. Supplementation with iron may increase the risk of infection by invasive diarrheal pathogens, while supplementation with the remaining micronutrients may reduce this risk. These differences may be due to distinct regulatory effects each micronutrient has on the pathogen-specific immune response, as well as on the virulence of specific pathogens. The findings of these studies suggest that micronutrient supplementation of children must take into account the pathogens prevalent within communities as reflected by their diarrheal disease burdens. The effectiveness of combining multiple micronutrients into one supplement must also be reconsidered.
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Affiliation(s)
- Kurt Z Long
- Harvard School of Public Health, Department of Nutrition, Harvard School of Public Health, 1663 Tremont Street, Boston, MA 02115, USA.
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Hughes S, Kelly P. Interactions of malnutrition and immune impairment, with specific reference to immunity against parasites. Parasite Immunol 2006; 28:577-88. [PMID: 17042929 PMCID: PMC1636690 DOI: 10.1111/j.1365-3024.2006.00897.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Accepted: 05/08/2006] [Indexed: 12/31/2022]
Abstract
1. Clinical malnutrition is a heterogenous group of disorders including macronutrient deficiencies leading to body cell mass depletion and micronutrient deficiencies, and these often coexist with infectious and inflammatory processes and environmental problems. 2. There is good evidence that specific micronutrients influence immunity, particularly zinc and vitamin A. Iron may have both beneficial and deleterious effects depending on circumstances. 3. There is surprisingly slender good evidence that immunity to parasites is dependent on macronutrient intake or body composition.
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Affiliation(s)
- S Hughes
- Tropical Gastroenterology and Nutrition Group, University of Zambia School of Medicine, Lusaka, Zambia
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León-Sicairos N, Reyes-López M, Ordaz-Pichardo C, de la Garza M. Microbicidal action of lactoferrin and lactoferricin and their synergistic effect with metronidazole in Entamoeba histolytica. Biochem Cell Biol 2006; 84:327-36. [PMID: 16936803 DOI: 10.1139/o06-060] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lactoferrin (Lf), in its iron-free form, has been shown to inhibit the growth of pathogenic microorganisms. In the light of new agents to control amoebiasis, the microbicidal activity of human and bovine Lf and bovine lactoferricin (bLfcin, fragment 4-14), and of each combined with metronidazole, the main drug used in amoebiasis, was evaluated in trophozoites of Entamoeba histolytica. Both lactoferrins and bLfcin were able to kill amoebas in a concentration-dependent manner. This killing effect was modulated according to the culture age, pH, and temperature. Parasites obtained from the stationary phase were more susceptible to Lf than those from the early exponential phase. The effect of Lf and its derived peptide, bLfcin, was prevented by both Fe2+ and Fe3+. However, the divalent cations Mg2+ and Ca2+ prevented the killing effect of Lf but not of bLfcin. A synergistic amoebicidal effect was found between metronidazole and human Lf, bovine Lf, or bLfcin. These data suggest that Lf and bLfcin might be used in amoebiasis if they are administered with a low dose of metronidazole to diminish the toxicity of this drug. Thus, Lf and bLfcin are therapeutically potential candidates for use as antiamoebics in patients.
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Affiliation(s)
- Nidia León-Sicairos
- Departamento de Biología Celular, Centro de Investigación y de Estudios Avanzados del IPN. Apdo. Postal 14-740, México, D. F. 07000, México
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Oppenheimer SJ. Iron and its relation to immunity and infectious disease. J Nutr 2001; 131:616S-633S; discussion 633S-635S. [PMID: 11160594 DOI: 10.1093/jn/131.2.616s] [Citation(s) in RCA: 396] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The continuing unresolved debate over the interaction of iron and infection indicates a need for quantitative review of clinical morbidity outcomes. Iron deficiency is associated with reversible abnormalities of immune function, but it is difficult to demonstrate the severity and relevance of these in observational studies. Iron treatment has been associated with acute exacerbations of infection, in particular, malaria. Oral iron has been associated with increased rates of clinical malaria (5 of 9 studies) and increased morbidity from other infectious disease (4 of 8 studies). In most instances, therapeutic doses of oral iron were used. No studies in malarial regions showed benefits. Knowledge of local prevalence of causes of anemia including iron deficiency, seasonal malarial endemicity, protective hemoglobinopathies and age-specific immunity is essential in planning interventions. A balance must be struck in dose of oral iron and the timing of intervention with respect to age and malaria transmission. Antimalarial intervention is important. No studies of oral iron supplementation clearly show deleterious effects in nonmalarious areas. Milk fortification reduced morbidity due to respiratory disease in two very early studies in nonmalarious regions, but this was not confirmed in three later fortification studies, and better morbidity rates could be achieved by breast-feeding alone. One study in a nonmalarious area of Indonesia showed reduced infectious outcome after oral iron supplementation of anemic schoolchildren. No systematic studies report oral iron supplementation and infectious morbidity in breast-fed infants in nonmalarious regions.
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Singhal A, Morley R, Abbott R, Fairweather-Tait S, Stephenson T, Lucas A. Clinical safety of iron-fortified formulas. Pediatrics 2000; 105:E38. [PMID: 10699140 DOI: 10.1542/peds.105.3.e38] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Iron-fortified formulas are recommended throughout infancy and are frequently used beyond, yet safety aspects have been inadequately studied. Iron could theoretically increase pro-oxidant stress, with potential adverse effects, including infection risk, and some clinicians suspect that iron-fortified formulas induce gastrointestinal disturbance. OBJECTIVE A planned component of a large intervention trial has been to test the hypothesis that infants receiving iron-fortified formula do not have a higher incidence of infections (primary outcome) or gastrointestinal problems (secondary outcome) than infants on low iron-formulas or cow's milk. Methods. Children (n = 493) 9 months old receiving cow's milk were recruited in 3 UK centers and randomized to: 1) cow's milk as before, 2) formula containing.9 mg/L of iron, or 3) an otherwise identical formula but containing 12 mg/L of iron. Children were followed at 3 monthly intervals and the episodes of infections, diarrhea and constipation, and general morbidity to 18 months old were recorded. Hematologic indices of iron status were determined at 18 months old. RESULTS Serum ferritin concentrations were increased in infants receiving iron-fortified formula but there were no intergroup differences in incidence of infection, gastrointestinal problems, or in general morbidity or weight gain. CONCLUSIONS We were unable to identify adverse health effects in older infants and toddlers consuming a high iron-containing formula (12 mg/L) even when used in populations with a low incidence of iron deficiency.
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Affiliation(s)
- A Singhal
- Medical Research Council Childhood Nutrition Research Centre, Institute of Child Health, London, United Kingdom.
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19
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Sheik-Mohamed A, Velema JP. Where health care has no access: the nomadic populations of sub-Saharan Africa. Trop Med Int Health 1999; 4:695-707. [PMID: 10583904 DOI: 10.1046/j.1365-3156.1999.00473.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Nomadic and seminomadic pastoralists make optimal use of scarce water and pasture in the arid regions south of the Sahara desert, spreading from Mauretania in the west to Somalia in East Africa. We attempted to summarize the fragmentary evidence from the literature on the health status of these populations and to assess the best ways to provide them with modern health care. Infant mortality is higher among nomadic than among neighbouring settled populations, but childhood malnutrition is less frequent. Nomads often avoid exposure to infectious agents by moving away from epidemics such as measles. Trachoma is highly prevalent due to flies attracted by cattle. The high prevalence of tuberculosis is ascribed to the presence of cattle, crowded sleeping quarters and lack of health care; treatment compliance is generally poor. Guinea worm disease is common due to unsafe water sources. Helminth infections are relatively rare as people leave their waste behind when they move. Malaria is usually epidemic, leading to high mortality. Sexually transmitted diseases spread easily due to lack of treatment. Leishmaniasis and onchocerciasis are encountered; brucellosis occurs but most often goes undetected. Drought forces nomads to concentrate near water sources or even into relief camps, with often disastrous consequences for their health. Existing health care systems are in the hands of settled populations and rarely have access to nomads due to cultural, political and economic obstacles. A primary health care system based on nomadic community health workers is outlined and an example of a successful tuberculosis control project is described. Nomadic populations are open to modern health care on the condition that this is not an instrument to control them but something they can control themselves.
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Affiliation(s)
- A Sheik-Mohamed
- Department of Public Health, Erasmus University, Rotterdam and The Netherlands Institute for Health Sciences
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20
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Abstract
To survive and replicate in vertebrate hosts, protozoan and fungal invaders must be capable of securing host iron. Successful pathogens obtain the metal from either extraction of heme, binding of siderophilins, binding of siderophores, and/or iron pools within host cells. The actual strategy can vary with the availability of iron in the particular host milieu. As a corollary, hosts have developed an elaborate iron withholding defense system. Conditions that can compromise the system as well as procedures that can strengthen it are reviewed.
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Affiliation(s)
- E D Weinberg
- Department of Biology, Indiana University, Bloomington 47405, USA.
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21
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22
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Gray S. Butterfat feeding in early infancy in african populations: New hypotheses. Am J Hum Biol 1998; 10:163-178. [PMID: 28561444 DOI: 10.1002/(sici)1520-6300(1998)10:2<163::aid-ajhb3>3.0.co;2-m] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/1996] [Accepted: 09/13/1996] [Indexed: 12/11/2022] Open
Abstract
The feeding of butterfat and animal milk to infants during their first 6 months has been documented in a number of pastoralist populations in Africa and elsewhere. In the view of the majority of nutrition scientists and physicians, this practice heightens the risk of malnutrition and infection for the infant. Where these nonbreastmilk foods are used to replace breastmilk, this view certainly is justified. In high-risk populations who use foods such as butterfat as complements to unrestricted breastfeeding, however, the relationship between early supplementation and infant growth and morbidity may be complex. Moreover, it may be mediated by the nutritional status of mothers and the nutritional adequacy of their breastmilk. In this work, the ecological context of butterfat feeding in Turkana, Kenya, is examined. It is argued that butterfat promotes positive infant energy balance prior to the critical period of the transition to active immunity, which occurs during the stressful dry season. Breastmilk alone may be inadequate to sustain growth and fat storage of young infants, since the diet and nutritional status of Turkana mothers suggest that fat content of their milk may be at the low end of the human range. In an environment where selection pressure is assumed to be high, a strategy of complementing the fat in human milk with butterfat may prolong positive energy balance of infants and enhance their resistance to infection and their survival during the critical period. Hence, it is an important component of human adaptation in Turkana. Am. J. Hum. Biol. 10:163-178, 1998. © 1998 Wiley-Liss, Inc.
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Abstract
Nomadism is a highly specialised mode of life that enables humans to exploit resources that are widely distributed over space and time. The isolation and remoteness of many nomad populations have limited studies on the macroepidemiology of parasitic infection in nomad populations. From the available information, the influence of a number of factors on the prevalence and transmission of parasitic infections in nomads is discussed. Environmental conditions, especially relative humidity and temperature, profoundly influence parasitic diseases. Human behaviour varies with cultural factors and influences exposure to disease. Periodic movements of nomads may either remove them and their animals from contaminated environments or may bring then into contact, often seasonally, with infections. There may be a strong ecological interdependence between diet and infection and disease in nomadic groups. Finally, the influence of drought can be profound in that seasonal or prolonged drought promotes concentration of populations in small areas or their sedenterisation, often with an increase in parasite transmission. Relevant information that needs to be acquired to develop appropriate practical and cost-effective health and veterinary care and control programmes for nomadic populations and their livestock is outlined.
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24
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Fenves AZ. The Interrelationship Between Iron and Infectious Diseases. Proc (Bayl Univ Med Cent) 1990. [DOI: 10.1080/08998280.1990.11929720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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25
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Iheanacho EN, Samuni A, Avramovici-Grisaru S, Sarel S, Spira DT. Inhibition of Plasmodium falciparum growth by a synthetic iron chelator. Trans R Soc Trop Med Hyg 1990; 84:213-6. [PMID: 2202102 DOI: 10.1016/0035-9203(90)90259-h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The susceptibility of the chloroquine-resistant malaria parasite Plasmodium falciparum (FCR-3) to a pyridoxal-based iron chelator was tested. 10 microM of the chelator 1[N-ethoxycarbonylmethyl-pyridoxy-lidenium]-2-[2'-pyri dyl] hydrazine bromide (code name L2-9) effectively inhibited growth in vitro of the parasites. Presaturation of the chelator with either ferric or ferrous iron partially blocked the inhibitory effect. Two hours' exposure of parasites to 20 microM L2-9 was sufficient to inhibit their growth irreversibly. Desferrioxamine blocked the inhibitory effect of L2-9. It is suggested that the chelator may be acting by generating free radicals in complexing intracellular iron.
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Affiliation(s)
- E N Iheanacho
- Kuvin Centre for the Study of Infectious and Tropical Diseases, Hadassah Medical School, Jerusalem, Israel
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26
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Martínez JL, Delgado-Iribarren A, Baquero F. Mechanisms of iron acquisition and bacterial virulence. FEMS Microbiol Rev 1990; 6:45-56. [PMID: 2186760 DOI: 10.1111/j.1574-6968.1990.tb04085.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- J L Martínez
- Instituto de Investigaciones Biomédicas CSIC, Facultad de Medicina U.A.M. C/Arturo Duperier no. 4, Madrid, Spain
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27
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Oppenheimer SJ. Iron and infection: the clinical evidence. ACTA PAEDIATRICA SCANDINAVICA. SUPPLEMENT 1989; 361:53-62. [PMID: 2485586 DOI: 10.1111/apa.1989.78.s361.53] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Iron deficiency is prevalent in childhood in the developed and developing countries. Programs of presumptive therapy, mass supplementation and food fortification have been introduced in many countries. The unresolved debate over the interaction of iron and infection in the clinical setting prompts re-evaluation of these practices. Situations of iron overload are associated with increased susceptibility to certain infections, although the exact mechanisms may vary with the main pathology. Iron treatment has been associated with acute exacerbations of infection, in particular malaria. In most instances parenteral iron was used. In the neonate parenteral iron is associated with serious E. coli sepsis. In one country, with endemic malaria, parenteral iron was associated with increased rates of malaria and increased morbidity due to respiratory disease in infants. In contrast in non-malarious countries studies of oral iron supplementation have if anything shown a reduction in infectious morbidity. Methodological problems in the latter reports indicate the need for further controlled prospective studies with accurate morbidity recording if informed recommendations are to be made.
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Affiliation(s)
- S J Oppenheimer
- Department of Paediatrics, Universiti Sains Malaysia, Kubang Kerian, Kelantan
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28
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Islam A, Stoll BJ, Ljungstrom I, Biswas J, Nazrul H, Huldt G. The prevalence of Entamoeba histolytica in lactating women and in their infants in Bangladesh. Trans R Soc Trop Med Hyg 1988; 82:99-103. [PMID: 2902705 DOI: 10.1016/0035-9203(88)90276-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Entamoeba histolytica was studied in 33 lactating women and their infants in a periurban village in Bangladesh. Infant-mother pairs were followed for a period of 10-15 months: 67% of mothers excreted E. histolytica during the observation period, the majority for 3 months or more. Only one mother was symptomatic, with a mild, non-dysenteric diarrhoea. 58% of mothers were seropositive, several of them continuously and with a high titre, indicating past invasive infection. 67% had detectable antibodies in breast milk and 36% in saliva. Despite the high prevalence of E. histolytica in these mothers, infants were mostly uninfected: E. histolytica cysts in small numbers were found in only 2 of 1200 samples from infants aged 6 and 10 months. Several of the children were infected with Giardia lamblia. Although lower exposure to E. histolytica than to Giardia may account for the difference in infant infection rates with these parasites, defence mechanisms possibly exist which protect against E. histolytica but are ineffective against Giardia.
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Affiliation(s)
- A Islam
- International Centre for Diarrhoeal Disease Research, Dhaka, Bangladesh
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Arellano J, Isibasi A, Miranda R, Higuera F, Granados J, Kretschmer RR. HLA antigens associated to amoebic abscess of the liver in Mexican mestizos. Parasite Immunol 1987; 9:757-60. [PMID: 2893327 DOI: 10.1111/j.1365-3024.1987.tb00543.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Worldwide prevalence of amoebiasis is estimated at 4 x 10(8) cases/year, yet only one of about 300 individuals harbouring Entamoeba histolytica suffers tissue invasion and these cases are mostly concentrated in certain areas of Asia, Africa and Latin America. Patients with amoebic abscess of the liver (AAL) represent only a small fraction of that. These contrasting figures have been tentatively explained on the one hand through variations in sex, immunocompetence, nutritional and other socioeconomic features of the host, and on the other hand through differences in parasite virulence. In order to explore a possible association between the major histocompatibility complex (MHC) and AAL susceptibility, we studied the HLA profile in 31 Mexican mestizos with AAL and compared it to race and socioeconomically matched controls. Mexican mestizo patients with AAL revealed a significant increase in HLA-Bw16 and HLA-DR3 which could suggest an HLA-related susceptibility to liver invasion by E. histolytica.
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Affiliation(s)
- J Arellano
- Division of Immunology, Unidad de Investigación Biomédica, México, D. F
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30
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Ilardi I, Sebastiani A, Leone F, Madera A, Bile MK, Shiddo SC, Mohamed HH, Amiconi G. Epidemiological study of parasitic infections in Somali nomads. Trans R Soc Trop Med Hyg 1987; 81:771-2. [PMID: 3449997 DOI: 10.1016/0035-9203(87)90027-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
In Somali nomads the incidence of intestinal helminths is very low compared with that observed in Somalian closed institutions and practically no Entamoeba infection occurs. Schistosoma haematobium eggs are observed in urine of 50% of adults nomads. Immunological tests reveal that the relative prevalences of leishmaniasis (the lowest), malaria, and toxoplasmosis (the highest) in nomads are similar to those shown by the same techniques in settled communities.
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Affiliation(s)
- I Ilardi
- Institute of Infectious Diseases, Faculty of Medicine, University La Sapienza, Rome, Italy
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31
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Fritsch G, Sawatzki G, Treumer J, Jung A, Spira DT. Plasmodium falciparum: inhibition in vitro with lactoferrin, desferriferrithiocin, and desferricrocin. Exp Parasitol 1987; 63:1-9. [PMID: 3542546 DOI: 10.1016/0014-4894(87)90072-5] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The microbial iron chelators desferriferrithiocin and desferricrocin as well as human lactoferrin were tested in vitro against Plasmodium falciparum. The microbial chelators inhibit the growth of P. falciparum in a dose dependent way. Parasite multiplication is stopped at 25-30 microM desferriferrithiocin, whereas 60-90 microM desferricrocin are needed to exhibit the same effect. After iron saturation, the microbial chelators are ineffective. Human lactoferrin (30 microM), both iron free and iron saturated, inhibits P. falciparum. A 3-day preincubation of host erythrocytes with iron free and iron saturated lactoferrin prior to infection enhances this effect, which is therefore attributed to lactoferrin bound iron. It has been suggested that the lactoferrin/iron complex generates oxygen free radicals, which may cause membrane damage of both erythrocyte and parasite. This process can be considered to lead to growth inhibition of the parasite.
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Rabo E, Taranger J. Scandinavian model for eliminating measles, mumps, and rubella. BRITISH MEDICAL JOURNAL 1984; 289:1402-4. [PMID: 6437574 PMCID: PMC1443676 DOI: 10.1136/bmj.289.6456.1402] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Pehrson PO. Amoebiasis in a non-endemic country. Epidemiology, presenting symptoms and diagnostic methods. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1983; 15:207-14. [PMID: 6308756 DOI: 10.3109/inf.1983.15.issue-2.14] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
392 patients with amoebiasis, diagnosed at Roslagstull Hospital, Stockholm during 10 yr, are reviewed. The disease is increasing in frequency, due both to increased travelling by Swedish citizens and immigration from non-European countries. The risk for an ordinary charter tourist is, however, rather low. Two-thirds of the patients were symptomatic and one-third were regarded as asymptomatic cyst carriers. The importance of repeated examination of stool samples and examinations using different techniques, especially direct microscopy of fresh faeces, is pointed out. The latter technique is in our laboratory shown to be as efficient in cases with no diarrhoea as in those with diarrhoea, with trophozoites demonstrated in the same frequency in both groups. Sigmoidoscopy with scrapings was seldom of diagnostic value.
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van Asbeck BS, Verhoef J. Iron and host defence. EUROPEAN JOURNAL OF CLINICAL MICROBIOLOGY 1983; 2:6-10. [PMID: 6840059 DOI: 10.1007/bf02019915] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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36
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37
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Watson RR, Petro TM. Resistance to bacterial and parasitic infections in the nutritionally compromised host. Crit Rev Microbiol 1982; 10:297-315. [PMID: 6365458 DOI: 10.3109/10408418209113566] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Over the past few years the relationships and interactions of diet, disease, and immunology are becoming better defined with the development and understanding of host defenses. Nutritional state, immunity, and disease all influence each other in the hospitalized patient, the elderly, and the young. Disease can alter nutritional needs and immune responses to antigens. The roles of both dietary excesses and deficiencies on cellular, secretory, and humoral immune responses are related to diseases and disease incidence in humans and experimental animals. Malnutrition alters incidence and severity of fungal, bacterial, viral, and parasitic pathogens. The mechanisms of altered disease resistance in nutritionally stressed animal models occurs via changes in the lymphoreticular endothelial system. The effects of common nutritional deficiencies, low protein, and low carbohydrate diets on antibody production, macrophage function, secretory IgA synthesis, and T-cell functions. Nutritional supplementation can increase lymphocyte function and decrease growth of some pathogens and tumors. Alternatively, obesity and high fat have roles in infectious disease and immunity.
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40
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Gurr MI. Review of the progress of dairy science: human and artificial milks for infant feeding. J DAIRY RES 1981; 48:519-54. [PMID: 7033314 DOI: 10.1017/s0022029900022020] [Citation(s) in RCA: 37] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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