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Jahan, F.

Publications and source records attributed to Jahan, F..

6 recordsLinked to original sources

Dirt floors and domestic animals are associated with soilborne exposure to antimicrobial resistant E. coli in rural Bangladeshi households

Soil can harbor enteropathogens and antimicrobial-resistant organisms in settings with domestic animals. We enrolled 49 households with young children (28 soil floors, 21 concrete floors) in Bangladesh and recorded animal ownership/management. Staff swabbed the floor of childrens sleeping area with a sterile sponge and collected floor dust and a child hand rinse. We used IDEXX QuantiTray/2000 with and without cefotaxime supplementation to enumerate cefotaxime-resistant and generic E. coli. There was 8.0 g/m2 of dust on soil floors vs. 0.2 g/m2 on concrete floors (p-value=0.005). We detected E. coli on 100% of soil vs. 86% of concrete floors and cefotaxime-resistant E. coli on 89% of soil vs. 43% of concrete floors (p-values<0.05). Cefotaxime-resistant E. coli prevalence on floors was 36% in compounds without animals, 79% in compounds with animals and 100% if animals stayed indoors overnight or the floor had animal feces; associations were strongest for chickens. In multivariable models, generic and cefotaxime-resistant E. coli counts were 1.5-2 log higher on soil vs. concrete floors, and counts on floors and child hands were 0.17-0.24 log higher for every 10 additional chickens owned (p-values<0.05). Efforts to mitigate infections and antimicrobial resistance in low-income countries should test flooring improvements and hygienic animal management. SynopsisIn rural Bangladeshi households, generic and cefotaxime-resistant E. coli were more common on soil floors than concrete floors and among households with higher cohabitation intensity with domestic animals, especially chickens.

microbiology↗

Pathogens and Antimicrobial Resistance Genes in Household Environments: A Study of Soil Floors and Cow Dung in Rural Bangladesh

In low- and middle-income countries, living in homes with soil floors and animal cohabitation may expose children to fecal organisms, increasing risk of enteric and antimicrobial-resistant infections. Our objective was to understand whether cow cohabitation in homes with soil floors in rural Bangladesh contributed to the presence and diversity of potential pathogens and antimicrobial resistance genes (ARGs) in the home. In 10 randomly selected households in rural Sirajganj District, we sampled floor soil and cow dung, which is commonly used as sealant in soil floors. We extracted DNA and performed shotgun metagenomic sequencing to explore potential pathogens and ARGs in each sample type. We detected 6 potential pathogens in soil only, 49 pathogens in cow dung only, and 167 pathogens in both soil and cow dung. Pathogen species with relative abundances >5% in both soil floors and cow dung from the same households included E. coli (N=8 households), Salmonella enterica (N=6), Klebsiella pneumoniae (N=2), and Pseudomonas aeruginosa (N=1). Cow dung exhibited modestly higher pathogen genus richness compared to soil floors (Wilcoxon signed-rank test p=0.002). Using Bray-Curtis dissimilarity, pathogen species community composition differed between floors and cow dung (PERMANOVA p<0.001). All soil floors and cow dung samples contained ARGs against antibiotic classes including sulfonamides, rifamycin, aminoglycosides, lincosamides, and tetracycline. Paired floor and cow dung samples shared ARGs against rifamycin. Our findings support the development of interventions to reduce soil and animal feces exposure in rural, low-income settings. ImportanceIn low-income countries, inadequate housing materials and animal cohabitation can lead to fecal contamination of rural homes. Contaminated soil floors are difficult to clean and may harbor organisms causing illness and antibiotic resistance, especially in young children, who frequently ingest soil. We sequenced soil floor and cow dung samples from households in Sirajganj district, Bangladesh and identified pathogens and antibiotic resistance genes. We detected 167 pathogens in both soil and cow dung; pathogens present in both sample types at the highest relative abundances were E. coli, Salmonella enterica, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Antibiotic resistance genes were found in all samples. In cow dung, the most common genes conferred resistance to the antibiotics lincosamide, rifamycin, cephamycin, and tetracycline. In soil floors, the most common genes conferred resistance to rifamycin, sulfonamides, and aminoglycosides. Household soil and cow dung may be important reservoirs of pathogens and antimicrobial resistance in low-income countries.

microbiology↗

Effects of maternal exercise modes on infant cord blood proteome

The aim of this study was to show the effects of different maternal exercise modes on infant cord blood proteome. We used infant cord blood from two randomized controlled trials where women with a wide range of BMI and free of pregnancy complications participated in controlled and supervised aerobic, resistance, or combination (aerobic+resistance) exercise from <16 weeks of gestation until delivery. Results of this study showed that infant cord blood proteome is altered in a maternal exercise mode specific manner. Additionally, results showed 61 downregulated proteins common to all exercise modes, which correspond to gas transport, cellular stress response, reactive oxygen species metabolism, and other biological processes. Collectively, these data demonstrate the differential effect of maternal exercise modes on infant cord blood proteome.

physiology↗

Maternal exercise alters placental proteome in an exercise mode-specific manner

Maternal exercise is a widely recommended and safe intervention associated with the improvement of maternal gestational and infant metabolic health. While various modes of exercise are deemed safe during pregnancy, the effects of supervised maternal aerobic, resistance, and combination (aerobic+resistance) exercise remain understudied. Specifically, it remains unknown how different modes of maternal exercise affect the placenta, an organ central to maternal-fetal communication and successful pregnancy outcomes. This study aimed to characterize the placental proteomic changes in response to controlled and supervised maternal exercise during gestation. Results showed that the placental proteomic landscape changes in an maternal exercise mode-specific way. Additionally, proteomics revealed that [~]20% of the identified placental proteins were associated with maternal exercise volume during gestation. These results highlight the differential effect maternal exercise modes have on the placental proteome and further implicate the placenta in mediating the effects of maternal exercise on maternal and infant health.

developmental biology↗

Automated and closed clinical-grade manufacturing protocol produces potent NK cells against neuroblastoma cells and AML blasts

Natural killer (NK) cells have great potential as allogeneic immune cell therapy due to their natural ability to recognize and kill tumor cells, and due to their apparent safety. This study describes the development of an immunotherapy option tailored for high-risk acute myeloid leukemia (AML) in adults and neuroblastoma in children. A GMP-compliant manufacturing protocol for the local production of functionally potent NK cells is detailed in the study, including a comprehensive description of the quality control strategy and considerations for product batch specifications in early clinical development. The protocol is based on the closed, automated CliniMACS Prodigy(R) platform (Miltenyi Biotec) and a modified Natural Killer Cell Transduction (NKCT) process without transduction and expansion. NK cells are isolated from leukapheresis through CD3 depletion and CD56 enrichment, followed by a 12-hour activation with cytokines (500 IU/ml IL-2, 140 IU/ml IL-15). Three CliniMACS Prodigy(R) NKCT processes were executed, demonstrating the feasibility and consistency of the modified NKCT process. A three-step process without expansion, however, compromised the NK cell yield. T cells were depleted effectively, indicating excellent safety of the product for allogeneic use. Phenotypic and functional characterization of the NK cells before and after cytokine activation revealed a notable increase in the expression of activation markers, particularly CD69, consistent with enhanced functionality. Intriguingly, even following a brief 12-hour activation period, the NK cells exhibited increased killing efficacy against CD33+ AML blasts isolated from patients and against SH-SY5Y neuroblastoma (NBL) target cells in vitro, suggesting a potential therapeutic benefit for AML and NBL patients.

immunology↗

NAD+ depletion and altered mitochondrial function are key to the establishment of placental dysfunction in an inflammatory-driven subclass of preeclampsia

Preeclampsia (PE) is a pregnancy associated hypertensive disease. It is one of the major causes of pregnancy-related maternal/perinatal adverse health outcomes, with a lack of highly effective preventative strategies and/or therapeutic interventions. Our group has previously identified distinct subclasses of pathophysiology underlying a PE diagnosis, one of which exhibits heightened immune activation at the gestational parent-fetal interface, identified as inflammatory-driven PE. In non-pregnant populations, chronic inflammation is associated with reduced cellular availability of NAD+, a vitamin B3-derived metabolite involved in energy metabolism and mitochondrial function. Interestingly, specifically in placentas from women with inflammatory-driven PE, we observed increased activity of NAD+-consuming PARP enzymes and reduced NAD+ content. Moreover, these placentas had decreased expression of several mitochondrial oxidative phosphorylation (OXPHOS) proteins and evidence of oxidative damage. This human data was supported by cell culture findings, which likewise demonstrated increased PARP activity, coupled to decreased mitochondrial respiration rates and decreased invasive function of cultured HTR8 human trophoblast cells, following inflammatory induction by TNF-. Importantly, these adverse inflammatory effects were attenuated by boosting cellular NAD+ levels with nicotinamide riboside (NR). Finally, using an LPS-induced rodent model of inflammatory-driven PE, we demonstrated that NR administration (200mg/kg/day) from gestational day (GD) 1-19 could prevent the development of maternal hypertension and fetal/placental growth restriction, improve placental mitochondrial function, reduce placental inflammation and oxidative stress. Thus, this study demonstrates the critical role of NAD+ metabolism in maintaining healthy placental function and identifies NAD+ boosting as a promising preventative strategy for the inflammatory-driven subclass of PE. One sentence summaryBoosting NAD+ levels prevent inflammatory-driven preeclampsia by improving placental mitochondrial function.

molecular biology↗