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Small intestinal bacterial overgrowth (SIBO) occurs commonly, is difficult to treat, and frequently recurs. Bovine colostrum (BC) and chicken eggs contain immunoglobulins and other components that possess antimicrobial, immunoregulatory, and growth factor activities; however, it is not known if they have the ability to reduce injury caused by the presence of bacteria associated with SIBO (Streptococcus, Escherichia coli, Staphylococcus, Bacteroides, Klebsiella, Enterococcus, and Proteus) and infectious diarrhea (enteropathogenic Escherichia coli, Salmonella). We examined the effects of BC, egg, or the combination, on bacterial growth and bacteria-induced changes in transepithelial electrical resistance (TEER) and bacterial translocation across confluent Caco-2 monolayers. BC, egg, or the combination did not affect bacterial growth. Adding bacteria to monolayers reduced TEER and (with minor variations among species) increased bacterial translocation, increased monolayer apoptosis (increased caspase-3 and Baxα, reduced Bcl2), increased intercellular adhesion molecule 1 (ICAM-1), and reduced cell adhesion molecules zonulin1 (ZO1) and claudin-1. BC, egg, or the combination reduced these effects (all p < 0.01) and caused additional increases in vascular endothelial growth factor (VEGF) and Heat Shock Protein 70 (Hsp70) expression. We conclude that BC ± egg strengthens mucosal integrity against a battery of bacteria relevant for SIBO and for infectious diarrhea. Oral BC ± egg may have clinical value for these conditions, especially SIBO where eradication of precipitating organisms may be difficult to achieve.  相似文献   
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We investigated the evolution of drug-resistant Plasmodium falciparum in a village in eastern Sudan. The frequencies of alleles of 4 genes thought to be determinants of drug resistance were monitored from 1990 through 2001. Changes in frequencies of drug-resistance genes between wet and dry seasons were monitored from 1998 through 2000. Parasites were also typed for 3 putatively neutral microsatellite loci. No significant variation in frequencies was observed for the microsatellite loci over the whole study period or between seasons. However, genes involved in resistance to chloroquine showed consistent, significant increases in frequencies over time (rate of annual increase, 0.027/year for pfcrt and 0.018/year for pfmdr1). Genes involved in resistance to the second-line drug used in the area (Fansidar) remained at low frequencies between 1990 and 1993 but increased dramatically between 1998 and 2000, which is consistent with the advent of Fansidar usage during this period. For mutant alleles of the primary drug-resistance targets for chloroquine and pyrimethamine, higher frequencies were seen during the dry season than during the wet season. This cyclical fluctuation in drug-resistance genes most likely reflects seasonal variation in drug pressure and differences in the fitness of resistant and sensitive parasites.  相似文献   
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A bioactive macrophage factor, the polypeptide daintain/allograft inflammatory factor 1 (AIF1), has been isolated from porcine intestine. It was discovered when searching for intestinal peptides with effects on insulin release, and its purification was monitored by the influence of the peptide fractions on pancreatic glucose-induced insulin secretion. Daintain/AIF1 is a 146-aa residue polypeptide with a mass of 16,603 Da and an acetylated N terminus. An internal 44-residue segment with the sequence pattern –KR–KK–GKR– has a motif typical of peptide hormone precursors, i.e., dibasic sites for potential activation cleavages and at the sequentially last such site, the structure GKR. The latter is a signal for C-terminal amide formation in the processing of peptide hormones. Daintain/AIF1 is immunohistochemically localized to microglial cells in the central nervous system and to dendritic cells and macrophages in several organs. A particularly dense accumulation of daintain/AIF1-immunoreactive macrophages was observed in the insulitis affecting the pancreatic islets of prediabetic BB rats. When injected intravenously in mice, daintain/AIF1 at 75 pmol/kg inhibited glucose (1 g/kg)-stimulated insulin secretion, with a concomitant impairment of the glucose elimination, whereas at higher doses (7.5 and 75 nmol/kg), daintain/AIF1 potentiated glucose-stimulated insulin secretion and enhanced the glucose elimination. Its dual influence on insulin secretion in vivo at different peptide concentrations, and the abundance of macrophages expressing daintain/AIF1 in the pancreatic islets of prediabetic rats, suggest that daintain/AIF1 may have a role in connection with the pathogenesis of insulin-dependent diabetesmellitus.  相似文献   
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The expression of interferon inducible genes are reported to be heightened in systemic lupus erythematosus (SLE); nevertheless, not much is known regarding the genetic variants underlying these genes and their role in the pathogenesis of disease. Herein, we aim to explore the potential association and contribution of polymorphisms in MX1 gene (i) promoter with part of exon 1 (ii) intron 6, and (iii) their resulting haplotypes, with susceptibility to SLE. A total of 306 subjects, 152 SLE and 154 healthy controls (HC), were screened by direct sequencing method. Statistical analysis was carried out using appropriate software. The screening region of interest in MX1 revealed the existence of promoter (?123C/A, ?88G/T, ?20 A/C) and intron 6 (+9862G/A, +10190G/A, +9901C/G, +9920C/A, +9959C/T, +10047A/G) variants in SLE and HC. A significant association was observed between MX1 ?88G/T SNP and susceptibility to SLE (χ 2?=?4.18, p?=?0.04, OR?=?1.89, 95 % CI 1.03–3.5). Haplotype analysis also revealed increased risk of SLE among individuals carrying CTA haplotype (?123 C, ?88 T, ?20 A) (χ 2?=?5.74, p?=?0.017, OR?=?4.28, 95 % CI 1.30–14.06). None of the other tested variants showed any significant association with SLE. The present study is the first to reveal the influence of genetic variation in MX1 gene in susceptibility to SLE.  相似文献   
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With growing numbers of HIV-seropositive (HIV+) women of child-bearing age and increased access to effective clinical protocols for preventing mother-to-child transmission (MTCT) of HIV, mental health-related factors have become increasingly relevant due to their potential to affect the women’s quality of life, obstetric outcomes and risk of MTCT. This review synthesizes evidence from 53 peer-reviewed publications examining mental health-related variables in pregnant and postpartum HIV+ women. The presentation of results is organized by the level of socioeconomic resources in the countries where studies were conducted (i.e., high-, middle-, and low-income countries). It is concluded that psychiatric symptoms, particularly depression, and mental health vulnerabilities (e.g., inadequate coping skills) are widespread among pregnant HIV+ women globally and have a potential to affect psychological well-being, quality of life and salient clinical outcomes. The current body of evidence provides rationale for developing and evaluating clinical and structural interventions aimed at improving mental health outcomes and their clinical correlates in pregnant HIV+ women.  相似文献   
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Objectives:To evaluate acute cardiac injury in COVID-19 patients and its association with adverse outcomes including mortality in the United Arab Emirates (UAE) population.Methods:A retrospective study conducted between February and June 2020 in Dubai, UAE, for all laboratory-confirmed Coronavirus disease-19 patients. Demographic, clinical, laboratory, radiological, and clinical outcomes were compared between patients with and without acute cardiac injury.Results:During the study period, 203 patients were included, of which, 44 (21.7%) had evidence of acute cardiac injury. Compared with patients without acute cardiac injury, patients with acute cardiac injury were: older, had more shortness of breath, diabetes, hypertension, and more bilateral airspace shadowing on admission chest radiography. These patients also had a higher neutrophil count, C-reactive protein, procalcitonin, ferritin, D-dimers and lactate dehydrogenase but lower lymphocyte count. Regarding outcomes, these patients had higher intensive care admissions; a higher rate of complications including acute kidney and liver injury, acidosis, septic shock, acute respiratory distress syndrome, needed more mechanical ventilation, and had a significantly higher risk of death.Conclusion:Acute cardiac injury is common among Coronavirus disease-19 patients. These patients present with higher comorbidities, have high inflammatory markers and have greater risk for in-hospital multi-organ damage, need for mechanical ventilation, and death. Prompt full assessment and intervention are recommended.  相似文献   
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