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91.
Yi Lu Chun‐Fang Li Na‐Na Ping Yu‐Yao Sun Zheng Wang Gong‐Xiao Zhao Shi‐Hui Yuan Abdoulaye Issotina Zibrila Lynn Soong Jin‐Jun Liu 《Journal of biochemical and molecular toxicology》2020,34(5)
Oxidative stress induced by long‐term cyclosporine A (CsA) administration is a major cause of chronic nephrotoxicity, which is characterized by tubular atrophy, tubular cell apoptosis, and interstitial fibrosis in the progression of organ transplantation. Although hydrogen‐rich water (HRW) has been used to prevent various oxidative stress‐related diseases, its underlying mechanisms remain unclear. This study investigated the effects of HRW on CsA‐induced nephrotoxicity and its potential mechanisms. After administration of CsA (25 mg/kg/day), rats were treated with or without HRW (12 mL/kg) for 4 weeks. Renal function and vascular activity were investigated. Histological changes in kidney tissues were analyzed using Masson's trichrome and terminal deoxynucleotidyl transferase dUTP nick‐end labeling stains. Oxidative stress markers and the activation of the Kelch‐like ECH‐associated protein 1 (Keap1)/nuclear factor erythroid 2‐related factor 2 (Nrf2) signaling pathway were also measured. We found that CsA increased the levels of reactive oxygen species (ROS) and malonaldehyde (MDA), but it reduced glutathione (GSH) and superoxide dismutase (SOD) levels. Such alterations induced vascular dysfunction, tubular atrophy, interstitial fibrosis, and tubular apoptosis. This was evident secondary to an increase in urinary protein, serum creatinine, and blood urea nitrogen, ultimately leading to renal dysfunction. Conversely, HRW decreased levels of ROS and MDA while increasing the activity of GSH and SOD. This was accompanied by an improvement in vascular and renal function. Moreover, HRW significantly decreased the level of Keap1 and increased the expression of Nrf2, NADPH dehydrogenase quinone 1, and heme oxygenase 1. In conclusion, HRW restored the balance of redox status, suppressed oxidative stress damage, and improved kidney function induced by CsA via activation of the Keap1/Nrf2 signaling pathway. 相似文献
92.
93.
Cigarette smoke is the major risk factor associated with the development of chronic obstructive pulmonary disease and alters expression of proteolytic enzymes that contribute to disease pathology. Previously, we reported that smoke exposure leads to the induction of matrix metalloproteinase-1 (MMP-1) through the activation of ERK1/2, which is critical to the development of emphysema. To date, the upstream signaling pathway by which cigarette smoke induces MMP-1 expression has been undefined. This study demonstrates that cigarette smoke mediates MMP-1 expression via activation of the TLR4 signaling cascade. In vitro cell culture studies demonstrated that cigarette smoke-induced MMP-1 was regulated by TLR4 via MyD88/IRAK1. Blockade of TLR4 or inhibition of IRAK1 prevented cigarette smoke induction of MMP-1. Mice exposed to acute levels of cigarette smoke exhibited increased TLR4 expression. To further confirm the in vivo relevance of this signaling pathway, rabbits exposed to acute cigarette smoke were found to have elevated TLR4 signaling and subsequent MMP-1 expression. Additionally, lungs from smokers exhibited elevated TLR4 and MMP-1 levels. Therefore, our data indicate that TLR4 signaling, through MyD88 and IRAK1, plays a predominant role in MMP-1 induction by cigarette smoke. The identification of the TLR4 pathway as a regulator of smoke-induced protease production presents a series of novel targets for future therapy in chronic obstructive pulmonary disease. 相似文献
94.
Kassogue Yaya Diakite Brehima Kassogue Oumar Konate Issa Tamboura Kadidiatou Diarra Zoumana Dehbi Hind Nadifi Sellama Traore Cheick Bougadari Dao Sounkalo Doumbia Seydou Dolo Guimogo 《Molecular biology reports》2020,47(1):393-400
Molecular Biology Reports - Glutathione S-transferase genes, known to be highly polymorphic, are implicated in the process of phase II metabolism of many substrates, including xenobiotics,... 相似文献
95.
B. Sicard J. Catalan S. Ag'Atteynine D. Abdoulaye J. Britton-Davidian 《Journal of Biogeography》2004,31(1):5-18
Introduction The genus Arvicanthis (Lesson 1842) (Rodentia: Murinae), usually referred to as the unstriped grass rat, is mainly distributed in savanna and grassland habitats of Sub-Saharan Africa. Among the four chromosomal forms of Arvicanthis recently differentiated in Western and Central Africa, the one with a diploid chromosomal number (2n) of 62 and an autosomal fundamental number (NFa) of 62 or 64 is ascribed to Arvicanthis niloticus (Demarest 1822), while the one with 2n = 62 and a NFa between 74 and 76 is referred to A. ansorgei (Thomas 1910). Despite the broad area of sympatry recently uncovered along the inner delta of the Niger river in Mali [details in Volobouev et al. (2002) Cytogenetics and Genome Research, 96, 250–260], the distribution of the two species is largely parapatric and follows the latitudinal patterns of the West-African biogeographical domains, which are related to the latitudinal patterns of annual rainfall in this region. Here, we analyse the suggestion that the two species show specific adaptations to differences in climate aridity. Methods Karyologically screened animals were sampled in 19 localities in seasonally flooded regions located along the ‘Niger’ river in Mali and extending from 1100 to 200 mm of mean annual rainfall. The analysis of trapping success (TS) data allowed us to investigate the respective effects of climate (i.e. annual rainfall) and local (i.e. duration of the green herbaceous vegetation) aridity on the latitudinal and habitat distribution of the two species. Conclusions The broad zone of sympatry was found to correspond to a northward expansion of the recognized distribution area of A. ansorgei. TS values indicated that the two species responded very differently to climatic and local conditions of aridity. Arvicanthis ansorgei decreased in TS as regional conditions became more arid; a similar trend was also observed within regions where habitat occupancy decreased with local aridity. The higher TS observed in the most humid habitat relative to the others persisted throughout the latitudinal rainfall gradient. In contrast, TS of A. niloticus increased with latitudinal aridity. This species was present in more arid habitats than A. ansorgei from 1000 mm down to 400 mm of mean annual rainfall where a shift to the most humid habitat occurred. These opposite trends in TS distribution between species suggest that A. ansorgei is less adapted than A. niloticus to arid environments at both a regional and habitat level; thus, A. ansorgei would be able to invade dry regions only along the extensive floodplains bordering the inner delta of the ‘Niger’ river. Several biological traits that may be involved in limiting the southward distribution of A. niloticus are discussed. 相似文献
96.
Ingunn?Marie?S?EngebretsenEmail author Victoria?Nankabirwa Tanya?Doherty Abdoulaye?Hama?Diallo Jolly?Nankunda Lars?Thore?Fadnes Eva-Charlotte?Ekstr?m Vundli?Ramokolo Nicolas?Meda Halvor?Sommerfelt Debra?Jackson Thorkild?Tyllesk?r James?K?Tumwine 《International breastfeeding journal》2014,9(1):19
Background
Immediate and exclusive initiation of breastfeeding after delivery has been associated with better neonatal survival and child health and are recommended by the WHO. We report its impact on early infant feeding practices from the PROMISE-EBF trial.Methods
PROMISE-EBF was a cluster randomised behaviour change intervention trial of exclusive breastfeeding (EBF) promotion by peer counsellors in Burkina Faso, Uganda and South Africa implemented during 2006-2008 among 2579 mother-infant pairs. Counselling started in the last pregnancy trimester and mothers were offered at least five postnatal visits. Early infant feeding practices: use of prelacteal feeds (any foods or drinks other than breast milk given within the first 3 days), expressing and discarding colostrum, and timing of initiation of breastfeeding are presented by trial arm in each country. Prevalence ratios (PR) with 95% confidence intervals (95%CI) are given.Results
The proportion of women who gave prelacteal feeds in the intervention and control arms were, respectively: 11% and 36%, PR 0.3 (95% CI 0.2, 0.6) in Burkina Faso, 13% and 44%, PR 0.3 (95% CI 0.2, 0.5) in Uganda and 30% and 33%, PR 0.9 (95% CI 0.6, 1.3) in South Africa. While the majority gave colostrum, the proportion of those who expressed and discarded it in the intervention and control arms were: 8% and 12%, PR 0.7 (95% CI 0.3, 1.6) in Burkina Faso, 3% and 10%, PR 0.3 (95% CI 0.1, 0.6) in Uganda and 17% and 16%, PR 1.1 (95% CI 0.6, 2.1) in South Africa. Only a minority in Burkina Faso (<4%) and roughly half in South Africa initiated breastfeeding within the first hour with no large or statistically significant differences between the trial arms, whilst in Uganda the proportion of early initiation of breastfeeding in the intervention and control arms were: 55% and 41%, PR 0.8 (95% CI 0.7, 0.9).Conclusions
The PROMISE-EBF trial showed that the intervention led to less prelacteal feeding in Burkina Faso and Uganda. More children received colostrum and started breastfeeding early in the intervention arm in Uganda. Late breastfeeding initiation continues to be a challenge. No clear behaviour change was seen in South Africa.Trial registration
NCT00397150.97.
Safiatou Doumbo Tuan M. Tran Jules Sangala Shanping Li Didier Doumtabe Younoussou Kone Abdrahamane Traoré Aboudramane Bathily Nafomon Sogoba Michel E. Coulibaly Chiung-Yu Huang Aissata Ongoiba Kassoum Kayentao Mouctar Diallo Zongo Dramane Thomas B. Nutman Peter D. Crompton Ogobara Doumbo Boubacar Traore 《PLoS neglected tropical diseases》2014,8(9)
Background
Malaria and schistosomiasis often overlap in tropical and subtropical countries and impose tremendous disease burdens; however, the extent to which schistosomiasis modifies the risk of febrile malaria remains unclear.Methods
We evaluated the effect of baseline S. haematobium mono-infection, baseline P. falciparum mono-infection, and co-infection with both parasites on the risk of febrile malaria in a prospective cohort study of 616 children and adults living in Kalifabougou, Mali. Individuals with S. haematobium were treated with praziquantel within 6 weeks of enrollment. Malaria episodes were detected by weekly physical examination and self-referral for 7 months. The primary outcome was time to first or only malaria episode defined as fever (≥37.5°C) and parasitemia (≥2500 asexual parasites/µl). Secondary definitions of malaria using different parasite densities were also explored.Results
After adjusting for age, anemia status, sickle cell trait, distance from home to river, residence within a cluster of high S. haematobium transmission, and housing type, baseline P. falciparum mono-infection (n = 254) and co-infection (n = 39) were significantly associated with protection from febrile malaria by Cox regression (hazard ratios 0.71 and 0.44; P = 0.01 and 0.02; reference group: uninfected at baseline). Baseline S. haematobium mono-infection (n = 23) did not associate with malaria protection in the adjusted analysis, but this may be due to lack of statistical power. Anemia significantly interacted with co-infection (P = 0.009), and the malaria-protective effect of co-infection was strongest in non-anemic individuals. Co-infection was an independent negative predictor of lower parasite density at the first febrile malaria episode.Conclusions
Co-infection with S. haematobium and P. falciparum is significantly associated with reduced risk of febrile malaria in long-term asymptomatic carriers of P. falciparum. Future studies are needed to determine whether co-infection induces immunomodulatory mechanisms that protect against febrile malaria or whether genetic, behavioral, or environmental factors not accounted for here explain these findings. 相似文献98.
99.
Weiss GE Clark EH Li S Traore B Kayentao K Ongoiba A Hernandez JN Doumbo OK Pierce SK Branch OH Crompton PD 《PloS one》2011,6(1):e15983
Background
Antibodies that protect against Plasmodium falciparum (Pf) malaria are only acquired after years of repeated infections. The B cell biology that underlies this observation is poorly understood. We previously reported that “atypical” memory B cells are increased in children and adults exposed to intense Pf transmission in Mali, similar to what has been observed in individuals infected with HIV. In this study we examined B cell subsets of Pf -infected adults in Peru and Mali to determine if Pf transmission intensity correlates with atypical memory B cell expansion.Methodology/Principal Findings
In this cross-sectional study venous blood was collected from adults in areas of zero (U.S., n = 10), low (Peru, n = 18) and high (Mali, n = 12) Pf transmission. Adults in Peru and Mali were infected with Pf at the time of blood collection. Thawed lymphocytes were analyzed by flow cytometry to quantify B cell subsets, including atypical memory B cells, defined by the cell surface markers CD19+ CD20+ CD21− CD27− CD10−. In Peru, the mean level of atypical memory B cells, as a percent of total B cells, was higher than U.S. adults (Peru mean: 5.4% [95% CI: 3.61–7.28]; U.S. mean: 1.4% [95% CI: 0.92–1.81]; p<0.0001) but lower than Malian adults (Mali mean 13.1% [95% CI: 10.68–15.57]; p = 0.0001). In Peru, individuals self-reporting ≥1 prior malaria episodes had a higher percentage of atypical memory B cells compared to those reporting no prior episodes (≥1 prior episodes mean: 6.6% [95% CI: 4.09–9.11]; no prior episodes mean: 3.1% [95% CI: 1.52–4.73]; p = 0.028).Conclusions/Significance
Compared to Pf-naive controls, atypical memory B cells were increased in Peruvian adults exposed to low Pf transmission, and further increased in Malian adults exposed to intense Pf transmission. Understanding the origin, function and antigen specificity of atypical memory B cells in the context of Pf infection could contribute to our understanding of naturally-acquired malaria immunity. 相似文献100.
Lyke KE Dabo A Arama C Daou M Diarra I Wang A Plowe CV Doumbo OK Sztein MB 《PloS one》2012,7(2):e31647