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Capone, D.

Publications and source records attributed to Capone, D..

5 recordsLinked to original sources

Exploring the Pathogen Profiles of Ancient Feces

Analysis of ancient desiccated feces - termed paleofeces or coprolites - can unlock insights into the lives of ancient people. We collected desiccated feces from caves in the Rio Zape Valley in Mexico (725-920 CE). First, we extracted DNA with methods previously optimized for paleofeces. Then, we applied highly sensitive modern molecular tools (i.e., PCR pre-amplification followed by multi-parallel qPCR) to assess the presence of 30 enteric pathogens. We detected [≥]1 pathogen associated gene in each of the ten samples and a mean of 3.9 pathogens per sample. The targets detected included Blastocystis spp. (n=7), atypical enteropathogenic E. coli (n=7), Enterobius vermicularis (n=6), Entamoeba spp. (n=5), enterotoxigenic E. coli (n=5), Shigella spp./enteroinvasive E. coli (n=3), Giardia spp. (n=2), and E. coli O157:H7 (n=1). The protozoan pathogens we detected (i.e., Giardia spp. and Entamoeba spp.) have been previously detected in paleofeces via enzyme-linked immunoassay (ELISA), but have not via PCR. This work represents the first detection of Blastocystis spp. atypical enteropathogenic E. coli, enterotoxigenic E. coli, Shigella spp./enteroinvasive E. coli, and E. coli O157:H7 in paleofeces. These results suggest that sensitive modern molecular tools, such as PCR, can be used to evaluate ancient materials for genes of interest.

microbiology↗

Phylodynamics Uncovers the Transmission of Antibiotic-Resistant Escherichia coli between Canines and Humans in an Urban Environment

The role of canines in transmitting antibiotic resistant bacteria to humans in the urban environment is poorly understood. To elucidate this role, we utilized genomic sequencing and phylogenetics to characterize the burden and transmission dynamics of antibiotic resistant Escherichia coli (ABR-Ec) cultured from canine and human feces present on urban sidewalks in San Francisco, California. We collected a total of fifty-nine ABR-Ec from human (n=12) and canine (n=47) fecal samples from the Tenderloin and South of Market (SoMa) neighborhoods of San Francisco. We then analyzed phenotypic and genotypic antibiotic resistance (ABR) of the isolates, as well as clonal relationships based on cgMLST and single nucleotide polymorphisms (SNPs) of the core genomes. Using Bayesian inference, we reconstructed the transmission dynamics between humans and canines from multiple local outbreak clusters using the marginal structured coalescent approximation (MASCOT). Overall, we found human and canine samples to carry similar amounts and profiles of ABR genes. Our results provide evidence for multiple transmission events of ABR-Ec between humans and canines. In particular, we found one instance of likely transmission from canines to humans as well as an additional local outbreak cluster consisting of one canine and one human sample. Based on this analysis, it appears that canine feces act as an important reservoir of clinically relevant ABR-Ec within the urban environment. Our findings support that public health measures should continue to emphasize proper canine feces disposal practices, access to public toilets and sidewalk and street cleaning. Importance: Antibiotic resistance in E. coli is a growing public health concern with global attributable deaths projected to reach millions annually. Current research has focused heavily on clinical routes of antibiotic resistance transmission to design interventions while the role of alternative reservoirs such as domesticated animals remain less well understood. Our results suggest canines are part of the transmission network that disseminates high-risk multidrug resistance in E. coli within the urban San Francisco community. As such, this study highlights the need to consider canines, and potentially domesticated animals more broadly, when designing interventions to reduce the prevalence of antibiotic resistance in the community. Additionally, it showcases the utility of genomic epidemiology to reconstruct the pathways by which antimicrobial resistance spreads.

microbiology↗

Impact of an Urban Sanitation Intervention on Enteric Pathogen Detection in Soils

Environmental fecal contamination is common in many low-income cities, contributing to a high burden of enteric infections and associated negative sequelae. To evaluate the impact of a shared onsite sanitation intervention in Maputo, Mozambique on enteric pathogens in the domestic environment, we collected 179 soil samples at shared latrine entrances from intervention (n= 49) and control (n= 51) compounds during baseline (pre-intervention) and after 24 months (post-intervention) as part of the Maputo Sanitation Trial. We tested soils for the presence of nucleic acids associated with 20 enteric pathogens using a multiplex reverse transcription qPCR platform. We detected at least one pathogen-associated target in 91% (163/179) of soils and a median of 3 (IQR=1.5, 5) pathogens. Using a difference-in-difference analysis and adjusting for compound population, visibly wet soil, sun exposure, wealth, temperature, animal presence, and visible feces, we estimate the intervention reduced the probability of [≥]1 pathogen detected by 15% (adjusted prevalence ratio, aPR=0.85; 95% CI: 0.70, 1.0) and the total number of pathogens detected by 35% (aPR =0.65; 0.44, 0.95) in soil 24 months following the intervention. These results suggest that the intervention reduced the presence of some fecal contamination in the domestic environment, but pathogen detection remained prevalent 24-months following the introduction of new latrines.

molecular biology↗

Bayesian analysis of source tracking markers to estimate the effects of an urban sanitation intervention on human fecal contamination in Mozambique

Fecal source tracking (FST) may be useful to assess pathways of fecal contamination in domestic environments and to estimate the impacts of water, sanitation, and hygiene (WASH) interventions in low-income settings. We measured two non-specific and two human-associated fecal indicators in water, soil, and surfaces before and after a shared latrine intervention from low-income households in Maputo, Mozambique participating in the Maputo Sanitation (MapSan) trial. Up to a quarter of households were impacted by human fecal contamination, but trends were unaffected by improvements to shared sanitation facilities. The intervention reduced E. coli gene concentrations in soil but did not impact culturable E. coli or the prevalence of human FST markers in a difference-in-differences analysis. Using a novel Bayesian hierarchical modeling approach to account for human marker diagnostic sensitivity and specificity, we revealed a high amount of uncertainty associated with human FST measurements and intervention effect estimates. The field of microbial source tracking would benefit from adding measures of diagnostic accuracy to better interpret findings, particularly when FST analyses convey insufficient information for robust inference. With improved measures, FST could help identify dominant pathways of human and animal fecal contamination in communities and guide implementation of effective interventions to safeguard health. SYNOPSISAn urban sanitation intervention had minimal and highly uncertain effects on human fecal contamination after accounting for fecal indicator sensitivity and specificity. TOC GRAPHIC/ABSTRACT ART O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=108 SRC="FIGDIR/small/432000v2_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@312d2dorg.highwire.dtl.DTLVardef@8cf2caorg.highwire.dtl.DTLVardef@197b549org.highwire.dtl.DTLVardef@fefeb3_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Interferon-alpha2 but not interferon-gamma serum levels are associated with intramuscular fat in obese patients with nonalcoholic fatty liver disease

BackgroundIntramuscular triglycerides (IMTGs) represent an important energy supply and a dynamic fat-storage depot that can expand during periods of elevated lipid availability and a fatty ac-id source. Ultrasonography (US) of human skeletal muscles is a practical and reproducible method to assess both IMTG presence and entity.\n\nAlthough a crosstalk between cytokines in skeletal muscle and adipose tissue has been suggested in obesity, condition leading to hepatic steatosis (HS) or better defined as nonalcoholic fatty liver disease and cancer, there are still questions to be answered about the role of interferons (IFNs), alpha as well as gamma, and IMTG in obesity. We aimed at discovering any correlation between IFNs and IMTG.\n\nMethodsWe analysed anthropometric data, metabolic parameters and imaging features of a population of obese subjects with low-prevalence of co-morbidities but HS. The levels of serum IFNs were detected by a magnetic bead-based multiplex immunoassays.\n\nResultsSerum concentrations of IFN-alpha2 were increased, while serum levels of IFN-gamma were decreased confronted with those of controls; the severity of IMTG, revealed at US as Heckmatt scores, was inversely predicted by IFN-alpha2 serum concentrations; IMTG scores were not predicted by serum levels of IFN-gamma; IMTG scores were predicted by HS severity, ascertained at US; HS severity was predicted by visceral adipose tissue, assessed by US, but the latter was not instrumental to IMTG.\n\nDiscussion & ConclusionThis study has added some pieces of observation about the cytokine network regulating the interplay between IMTG and obesity in obese patients with HS.

epidemiology↗