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1.
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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Identification, isolation, and characterization of daintain (allograft inflammatory factor 1), a macrophage polypeptide with effects on insulin secretion and abundantly present in the pancreas of prediabetic BB rats 下载免费PDF全文
Zheng-Wang Chen Bo Ahren Claes-Gran
stenson Antonio Cintra Tomas Bergman Christer Mller Kjell Fuxe Viktor Mutt Hans Jrnvall Suad Efendic 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(25):13879-13884
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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Identification of Serotype in Culture Negative Pneumococcal Meningitis Using Sequential Multiplex PCR: Implication for Surveillance and Vaccine Design 下载免费PDF全文
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AbstractObjective: To assess whether asthma prevalence differs between Hispanic adults living in Puerto Rico and Hispanic adults of Puerto Rican descent living in the United States. Methods: We used 2008–2010 Behavioral Risk Factor Surveillance System data, administered in Puerto Rico for Hispanic adults living in Puerto Rico (Hispanics in Puerto Rico), and 2008–2010 National Health Interview Survey data for Hispanic adults of Puerto Rican descent living in the United States (Puerto Rican Americans). We used 95% confidence intervals (CIs) to compare asthma prevalence between corresponding subgroups; non-overlapping CIs indicate statistical significance. Chi-square test and multivariate logistic regression were used to assess the association between current asthma status and socio-demographic factors and health risk behaviors within each Puerto Rican population. Results: Current asthma prevalence among Hispanics in Puerto Rico (7.0% [6.4%–7.7%]) was significantly lower than the prevalence among Puerto Rican Americans (15.6% [13.0%–18.1%]). The prevalence among almost all socio-demographic and health risk subgroups of Hispanics in Puerto Rico was significantly lower than the prevalence among the corresponding subgroups of Puerto Rican Americans. Adjusting for potential confounders did not alter the results. Asthma prevalence was significantly associated with obesity among Puerto Rican Americans (adjusted prevalence ratios [aPR]?=?1.5 [1.1–2.0]), and among Hispanics in Puerto Rico was associated with obesity (aPR?=?1.6 [1.3–1.9]), smoking (aPR?=?1.4 [1.1–1.9]) and being female (aPR?=?1.9 [1.5–2.4]). Conclusion: Asthma was more prevalent among Puerto Rican Americans than Hispanics in Puerto Rico. Although the observed associations did not explain all variations in asthma prevalence between these two populations, they may lay the foundation for future research. 相似文献
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Abdel-Muhsin AM Mackinnon MJ Ali E Nassir el-KA Suleiman S Ahmed S Walliker D Babiker HA 《The Journal of infectious diseases》2004,189(7):1239-1244
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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Suad AlFadhli Mashael Al-Mutairi Bader Al Tameemi Rasheeba Nizam 《Clinical rheumatology》2016,35(3):623-629
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
10.
Suad Kapetanovic Priscilla Dass-Brailsford Diana Nora Nicholas Talisman 《AIDS and behavior》2014,18(6):1152-1173
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