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1.
Artículo en Inglés | MEDLINE | ID: mdl-38929028

RESUMEN

This paper examines how African immigrants living with HIV negotiate and reconstruct their productive (i.e., educational and career opportunities), sexual, and reproductive identities. We used data from a mixed-methods study to explore how stigma and social networks in which participants were embedded shaped how they understood and negotiated their role expectations and responsibilities. Participants revealed how HIV not only changed their identities and limited their sex life, partner choices, and fundamental decisions about fertility and reproduction, but also presented them with the opportunity to reinvent/reshape their lives. Our analysis revealed that the cultural discourses about illness and HIV in participant's countries of origin, the acculturative and migratory stressors, and the competing influences and expectations from family and friends in their home and host countries shape their illness experience, and how they adjust to life with HIV. This paper builds on sociological understanding of illness experience as a social construct that shapes the ill person's identity, role, and function in society. Specifically, the paper contributes to discourses on how (i) participants' social location and identity (as transnational migrants adjusting to acculturative stressors associated with resettlement into a new country), (ii) cultural discourses about illness and HIV in their countries of origin, and (iii) embeddedness in transnational social networks influence health outcomes, including lived experiences with chronic illnesses and stigmatized conditions such as HIV.


Asunto(s)
Emigrantes e Inmigrantes , Infecciones por VIH , Estigma Social , Humanos , Infecciones por VIH/psicología , Infecciones por VIH/etnología , Masculino , Femenino , Emigrantes e Inmigrantes/psicología , Adulto , Persona de Mediana Edad , Apoyo Social , África/etnología , Red Social
2.
Sci Rep ; 14(1): 10394, 2024 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710815

RESUMEN

Tobacco use significantly influences the oral microbiome. However, less is known about how different tobacco products specifically impact the oral microbiome over time. To address this knowledge gap, we characterized the oral microbiome of cigarette users, smokeless tobacco users, and non-users over 4 months (four time points). Buccal swab and saliva samples (n = 611) were collected from 85 participants. DNA was extracted from all samples and sequencing was carried out on an Illumina MiSeq, targeting the V3-V4 region of the 16S rRNA gene. Cigarette and smokeless tobacco users had more diverse oral bacterial communities, including a higher relative abundance of Firmicutes and a lower relative abundance of Proteobacteria, when compared to non-users. Non-users had a higher relative abundance of Actinomyces, Granulicatella, Haemophilus, Neisseria, Oribacterium, Prevotella, Pseudomonas, Rothia, and Veillonella in buccal swab samples, compared to tobacco users. While the most abundant bacterial genera were relatively constant over time, some species demonstrated significant shifts in relative abundance between the first and last time points. In addition, some opportunistic pathogens were detected among tobacco users including Neisseria subflava, Bulleidia moorei and Porphyromonas endodontalis. Overall, our results provide a more holistic understanding of the structure of oral bacterial communities in tobacco users compared to non-users.


Asunto(s)
Disbiosis , Microbiota , Boca , ARN Ribosómico 16S , Tabaco sin Humo , Humanos , Tabaco sin Humo/efectos adversos , Masculino , Femenino , Disbiosis/microbiología , Adulto , ARN Ribosómico 16S/genética , Boca/microbiología , Saliva/microbiología , Persona de Mediana Edad , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Fumadores , Adulto Joven , Fumar Cigarrillos/efectos adversos , Mucosa Bucal/microbiología
3.
Transplantation ; 108(7): e91-e105, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38587506

RESUMEN

BACKGROUND: Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial fibrosis, or endothelial changes, and eventually graft failure. The events leading to chronic rejection are still poorly understood and the gut microbiota is a known driving force in immune dysfunction. We previously showed that gut microbiota dysbiosis profoundly influences the outcome of vascularized cardiac allografts and subsequently identified biomarker species associated with these differential graft outcomes. METHODS: In this study, we further detailed the multifaceted immunomodulatory properties of protolerogenic and proinflammatory bacterial species over time, using our clinically relevant model of allogenic heart transplantation. RESULTS: In addition to tracing longitudinal changes in the recipient gut microbiome over time, we observed that Bifidobacterium pseudolongum induced an early anti-inflammatory phenotype within 7 d, whereas Desulfovibrio desulfuricans resulted in a proinflammatory phenotype, defined by alterations in leukocyte distribution and lymph node (LN) structure. Indeed, in vitro results showed that B pseudolongum and D desulfuricans acted directly on primary innate immune cells. However, by 40 d after treatment, these 2 bacterial strains were associated with mixed effects in their impact on LN architecture and immune cell composition and loss of colonization within gut microbiota, despite protection of allografts from inflammation with B pseudolongum treatment. CONCLUSIONS: These dynamic effects suggest a critical role for early microbiota-triggered immunologic events such as innate immune cell engagement, T-cell differentiation, and LN architectural changes in the subsequent modulation of protolerant versus proinflammatory immune responses in organ transplant recipients.


Asunto(s)
Bifidobacterium , Microbioma Gastrointestinal , Rechazo de Injerto , Trasplante de Corazón , Trasplante de Corazón/efectos adversos , Microbioma Gastrointestinal/inmunología , Rechazo de Injerto/inmunología , Rechazo de Injerto/microbiología , Rechazo de Injerto/prevención & control , Animales , Masculino , Factores de Tiempo , Supervivencia de Injerto , Disbiosis , Ratones Endogámicos C57BL , Inmunidad Innata , Inmunomodulación , Fenotipo , Probióticos/uso terapéutico , Ganglios Linfáticos/microbiología , Ganglios Linfáticos/inmunología
4.
Artículo en Inglés | MEDLINE | ID: mdl-38570896

RESUMEN

BACKGROUND: The role of altruism in the acceptance of novel preventive healthcare technologies like vaccines has not been thoroughly elucidated. METHODS: We 1:1 randomized n = 2004 Amazon Mechanical Turk (MTurk) participants residing in the USA into a control or treatment arm with vaccination decisions framed altruistically, to elicit their preferences for COVID-19 vaccination using web-based discrete choice experiments. We used conditional and mixed logit models to estimate the impact of framing decisions in terms of altruism on vaccination acceptance. RESULTS: Valid responses were provided by 1674 participants (control, n = 848; treatment, n = 826). Framing vaccination decisions altruistically had no significant effect on vaccination acceptance. Further, respondents' degree of altruism had no association with vaccination acceptance. LIMITATIONS: The MTurk sample may not be representative of the American population. We were unable to ascertain concordance between stated and revealed preferences. CONCLUSIONS AND IMPLICATIONS: Framing vaccination decisions in terms of altruism does not appear to significantly influence vaccination acceptance and may not be an effective nudging mechanism to increase the uptake of novel vaccines. Instead, a favorable vaccination profile appears to be the primary driver of uptake.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38443740

RESUMEN

In 2021, the African Cultural Alliance of North America (ACANA) implemented a community-based vaccine education and outreach program to decrease hesitancy and increase COVID-19 vaccine uptake among African immigrants in Philadelphia. The program had three components: (1) tailored messaging on the benefits of vaccines by trusted community health navigators in familiar languages/dialects, (2) use of educational/tabling events, and (3) establishment of a vaccine clinic in community settings. Using secondary data analysis, in-depth interviews, focus group discussions and a self-administered survey, we explored (i) the impact and effectiveness of the outreach program and extent of vaccine uptake, (ii) African immigrants' beliefs about the COVID-19 pandemic and the vaccine, and (iii) barriers and facilitators of vaccine knowledge, uptake, and hesitancy. Our analysis showed that ACANA's outreach program was effective in addressing several cultural, logistic, and systematic barriers to vaccine uptake. The program distributed 2000 educational/informational flyers, reached 3000 community members via social media campaigns, and an additional 2320 through other person-to-person outreach events. The program was effective and resulted in the vaccination of 1265 community members over the course of the outreach. The impact of this outreach underscores the critical role of community-based organizations in addressing COVID-19 vaccine hesitancy and increasing vaccine uptake in underserved and minority communities. The paper concludes with suggestions and recommendations for using community-based outreach programs to increase COVID-19 vaccine uptake and decrease hesitancy.

6.
J Transl Med ; 22(1): 269, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38475767

RESUMEN

BACKGROUND: Chemotherapy is a primary treatment for cancer, but its efficacy is often limited by cancer-associated bacteria (CAB) that impair tumor suppressor functions. Our previous research found that Mycoplasma fermentans DnaK, a chaperone protein, impairs p53 activities, which are essential for most anti-cancer chemotherapeutic responses. METHODS: To investigate the role of DnaK in chemotherapy, we treated cancer cell lines with M. fermentans DnaK and then with commonly used p53-dependent anti-cancer drugs (cisplatin and 5FU). We evaluated the cells' survival in the presence or absence of a DnaK-binding peptide (ARV-1502). We also validated our findings using primary tumor cells from a novel DnaK knock-in mouse model. To provide a broader context for the clinical significance of these findings, we investigated human primary cancer sequencing datasets from The Cancer Genome Atlas (TCGA). We identified F. nucleatum as a CAB carrying DnaK with an amino acid composition highly similar to M. fermentans DnaK. Therefore, we investigated the effect of F. nucleatum DnaK on the anti-cancer activity of cisplatin and 5FU. RESULTS: Our results show that both M. fermentans and F. nucleatum DnaKs reduce the effectiveness of cisplatin and 5FU. However, the use of ARV-1502 effectively restored the drugs' anti-cancer efficacy. CONCLUSIONS: Our findings offer a practical framework for designing and implementing novel personalized anti-cancer strategies by targeting specific bacterial DnaKs in patients with poor response to chemotherapy, underscoring the potential for microbiome-based personalized cancer therapies.


Asunto(s)
Antineoplásicos , Neoplasias , Animales , Ratones , Humanos , Cisplatino , Proteína p53 Supresora de Tumor , Fluorouracilo , Bacterias
7.
Alzheimers Dement ; 20(4): 2817-2829, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38426381

RESUMEN

BACKGROUND: Subjective cognitive impairment (SCI) measures in population-based surveys offer potential for dementia surveillance, yet their validation against established dementia measures is lacking. METHODS: We assessed agreement between SCI and a validated probable dementia algorithm in a random one-third sample (n = 1936) of participants in the 2012 National Health and Aging Trends Study (NHATS). RESULTS: SCI was more prevalent than probable dementia (12.2% vs 8.4%). Agreement between measures was 90.0% and of substantial strength. Misclassification rates were higher among older and less-educated subgroups due to higher prevalence of false-positive misclassification but did not vary by sex or race and ethnicity. DISCUSSION: SCI sensitivity (63.4%) and specificity (92.5%) against dementia were comparable with similar metrics for the NHATS probable dementia measure against the "gold-standard" Aging, Demographics, and Memory Study-based dementia criteria, implying that population-based surveys may afford cost-effective opportunities for dementia surveillance to assess risk and inform policy. HIGHLIGHTS: The prevalence of subjective cognitive impairment (SCI) is generally higher than that of a validated measure of probable dementia, particularly within the youngest age group, females, Whites, and persons with a college or higher degree. Percent agreement between SCI and a validated measure of probable dementia was 90.0% and of substantial strength (prevalence- and bias-adjusted kappa, 0.80). Agreement rates were higher in older and less-educated subgroups, driven by the higher prevalence of false-positive disagreement, but did not vary significantly by sex or race and ethnicity. SCI's overall sensitivity and specificity were 63.4% and 92.5%, respectively, against a validated measure of probable dementia, suggesting utility as a low-cost option for dementia surveillance. Heterogeneity in agreement quality across subpopulations warrants caution in its use for subgroup analyses.


Asunto(s)
Trastornos del Conocimiento , Disfunción Cognitiva , Demencia , Femenino , Humanos , Anciano , Trastornos del Conocimiento/epidemiología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Envejecimiento , Sensibilidad y Especificidad , Demencia/diagnóstico , Demencia/epidemiología
8.
Mol Phylogenet Evol ; 194: 108022, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38325534

RESUMEN

The world's largest butterfly genus Delias, commonly known as Jezebels, comprises ca. 251 species found throughout Asia, Australia, and Melanesia. Most species are endemic to islands in the Indo-Australian Archipelago or to New Guinea and nearby islands in Melanesia, and many species are restricted to montane habitats over 1200 m. We inferred an extensively sampled and well-supported molecular phylogeny of the group to better understand the spatial and temporal dimensions of its diversification. The remarkable diversity of Delias evolved in just ca. 15-16 Myr (crown age). The most recent common ancestor of a clade with most of the species dispersed out of New Guinea ca. 14 Mya, but at least six subsequently diverging lineages dispersed back to the island. Diversification was associated with frequent dispersal of lineages among the islands of the Indo-Australian Archipelago, and the divergence of sister taxa on a single landmass was rare and occurred only on the largest islands, most notably on New Guinea. We conclude that frequent inter-island dispersal during the Neogene-likely facilitated by frequent sea level change-sparked much diversification during that period. Many extant New Guinea lineages started diversifying 5 Mya, suggesting that orogeny facilitated their diversification. Our results largely agree with the most recently proposed species group classification system, and we use our large taxon sample to extend this system to all described species. Finally, we summarize recent insights to speculate how wing pattern evolution, mimicry, and sexual selection might also contribute to these butterflies' rapid speciation and diversification.


Asunto(s)
Mariposas Diurnas , Animales , Filogenia , Mariposas Diurnas/genética , Nueva Guinea , Australia , Ecosistema
9.
J Nutr ; 154(3): 1050-1057, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38311064

RESUMEN

BACKGROUND: The Household Food Security Survey Module (HFSSM) was not tailored to people with chronic diseases or young adults (YAs). OBJECTIVES: We aim to evaluate whether the 18-item HFSSM meets assumptions underlying the scale among YAs with diabetes. METHODS: Data from 1887 YAs with youth-onset type 1 diabetes or type 2 diabetes were used from the SEARCH for Diabetes in Youth Study, 2016-2019, and on 925 who returned for the SEARCH Food Security Cohort Study, 2018-2021, all of whom had completed the HFSSM. Guttman scaling properties (affirmation of preceding less severe items) and Rasch model properties (probability to answer an item based on difficulty level) were assessed. RESULTS: Items 3 (balanced meals) and 6 (eating less than one should) were affirmed more frequently than expected (nonmonotonic response pattern). At 1.2%-3.5%, item nonresponse was rare among type 1 diabetes but higher among type 2 diabetes (range: 3.1%-10.6%). Items 9 (not eating the whole day) and 3 did not meet the Guttman scaling properties. Rasch modeling revealed that item 3 had the smallest difficulty parameter. INFIT indices suggested that some responses to item 3 did not match the pattern in the rest of the sample. Classifying household food insecurity (HFI) based on items 1 and 2 compared with other 2-item combinations, including item 3, revealed a substantial undercount of HFI ranging from 5% to 8% points. CONCLUSIONS: Use of the HFSSM among YAs with diabetes could potentially result in biased HFI reporting and affect estimates of HFI prevalence in this population.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Adolescente , Humanos , Adulto Joven , Estudios de Cohortes , Abastecimiento de Alimentos , Seguridad Alimentaria
10.
J Prosthodont ; 33(4): 330-339, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37527556

RESUMEN

PURPOSE: To characterize the microbiome composition in peri-implant pocket of peri-implantitis and peri-implant sulcus controls using 16S rRNA gene sequencing. MATERIALS AND METHODS: In this controlled clinical cross-sectional study, 23 subjects with control implants (n = 14) and diseased implants (peri-implantitis, n = 21) were included. The peri-implant pocket/sulcus was sampled and used to extract DNA and amplify the 16S rRNA gene using universal primers targeting the V3-V4 regions. The resulting 16S PCR amplicons were sequenced on Illumina MiSeq, and the sequences were processed using DADA2 and the Human Oral Microbiome Database (HOMD) as references. Alpha and Beta diversity, as well as core microbiome and differential abundance analyses, were performed using the MicrobiomeAnalyst workflow. RESULTS: There were no significant differences in microbial diversity between control implants and implants with peri-implantitis (Shannon p = 0.82). Overall bacterial community structure assessed through beta diversity analysis was also not significantly different between the two groups (p = 0.18). However, high levels of Gram-negative bacteria were detected in peri-implant pockets compared to the control sulcus. Abundant species in peri-implantitis were Capnocytophaga leadbetteri, Treponema maltophilum, Peptostreptococcus, Neisseria, P. gingivalis, and Porphyromonas endodontali, Lactococcus lactis and Filifactor alocis (p < 0.05). Gram-positive bacteria such as Streptococcus salivaris, Prevotella melaninogenica, L. wadei, and Actinomyces spp. serve were more abundant in peri-implant control sulcus. CONCLUSIONS: Peri-implant sulcus in control implants harbors predominantly Gram-positive bacteria, whereas pockets of implants with peri-implantitis harbor predominantly Gram-negative bacteria.


Asunto(s)
Implantes Dentales , Microbiota , Periimplantitis , Humanos , Periimplantitis/microbiología , Implantes Dentales/efectos adversos , ARN Ribosómico 16S/genética , Estudios Transversales , Microbiota/genética
11.
J Nutr ; 154(2): 543-553, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38072157

RESUMEN

BACKGROUND: Typically, child exposure to food insecurity is assessed by caregiver reports of household food security. Child report has the potential for greater accuracy because it pertains only to the child whose experiences may differ from caregiver reports. OBJECTIVE: We assessed if adolescent-reported food insecurity was associated with levels of hemoglobin A1c (HbA1c), acute diabetes-related complications, depressive symptoms, and disordered eating behaviors in adolescents with type 1 diabetes, independently from household food security. METHODS: In a cross-sectional analysis of the multicenter SEARCH for Diabetes in Youth Cohort Study (phase 4, 2016-2019) including 601 adolescents aged 10-17 y with type 1 diabetes and their caregivers, household food security, and adolescent-reported food security were assessed using the 18-item Household Food Security Survey Module and the 6-item Child Food Security Assessment questionnaire. Age-stratified (10-13 and 14-17) regression models were performed to estimate independent associations, adjusting for sociodemographics, clinical factors, and household food security. RESULTS: Food insecurity was reported by 13.1% (n = 79) of adolescents and 15.6% (n = 94) of caregivers. Among adolescent-caregiver dyads, 82.5% (n = 496) of reports were concordant and 17.5% (n = 105) discordant, Cohen's κ= 0.3. Adolescent-reported food insecurity was not independently associated with HbA1c, diabetic ketoacidosis, and severe hypoglycemia, including in age-stratified analyses. Adolescent-reported food insecurity was independently associated with elevated odds of depressive symptoms [odds ratio (OR): 3.6; 95% confidence interval (CI): 1.3, 10.3] and disordered eating behaviors (OR: 2.5, 95% CI: 1.4, 4.6) compared with adolescents reporting food security; these associations remained in both age groups for disordered eating behaviors and in the older group for depressive symptoms. CONCLUSIONS: Adolescents with type 1 diabetes may experience food insecurity differently than caregivers. Adolescent-reported food insecurity was independently associated with depressive symptoms and disordered eating behaviors and thus may be an important attribute to assess in addition to household food security in adolescents with type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1 , Hemoglobina Falciforme , Salud Mental , Niño , Humanos , Adolescente , Autoinforme , Diabetes Mellitus Tipo 1/complicaciones , Estudios de Cohortes , Estudios Transversales , Composición Familiar , Abastecimiento de Alimentos , Seguridad Alimentaria
12.
Heliyon ; 9(12): e22448, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38046146

RESUMEN

Background: Pregnant women's understanding of maternal health information is critical in the application of information for pregnancy care, birth preparedness, and newborn care. However, the influence of socio-demographic characteristics on pregnant women's understanding of maternal health information is least understood. Purpose: The study examined the influence of social and demographic characteristics on pregnant women's comprehension of maternal health information. Methodology: A mixed research approach and descriptive cross-sectional design were applied. Questionnaires and focus group discussions were used to collect data from 132 pregnant women and 8 nurses/midwives. Data were analyzed using IBM SPSS version 21 and thematic analysis. Findings: Most of the pregnant women had a good ability to comprehend maternal health information. Level of education was found to influence the reading ability and language understanding ability of the pregnant women unlike age, marital status, income, and occupation. Age, level of education, monthly income, occupation, and marital status were found to influence the ability of pregnant women to understand maternal health information. Conclusion: The socio-demographic characteristics of pregnant women have an influence on their ability to comprehend maternal health information.

13.
BMC Microbiol ; 23(1): 394, 2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38066426

RESUMEN

Intrinsic metabolism shapes the immune environment associated with immune suppression and tolerance in settings such as organ transplantation and cancer. However, little is known about the metabolic activities in an immunosuppressive environment. In this study, we employed metagenomic, metabolomic, and immunological approaches to profile the early effects of the immunosuppressant drug tacrolimus, antibiotics, or both in gut lumen and circulation using a murine model. Tacrolimus induced rapid and profound alterations in metabolic activities within two days of treatment, prior to alterations in gut microbiota composition and structure. The metabolic profile and gut microbiome after seven days of treatment was distinct from that after two days of treatment, indicating continuous drug effects on both gut microbial ecosystem and host metabolism. The most affected taxonomic groups are Clostriales and Verrucomicrobiae (i.e., Akkermansia muciniphila), and the most affected metabolic pathways included a group of interconnected amino acids, bile acid conjugation, glucose homeostasis, and energy production. Highly correlated metabolic changes were observed between lumen and serum metabolism, supporting their significant interactions. Despite a small sample size, this study explored the largely uncharacterized microbial and metabolic events in an immunosuppressed environment and demonstrated that early changes in metabolic activities can have significant implications that may serve as antecedent biomarkers of immune activation or quiescence. To understand the intricate relationships among gut microbiome, metabolic activities, and immune cells in an immune suppressed environment is a prerequisite for developing strategies to monitor and optimize alloimmune responses that determine transplant outcomes.


Asunto(s)
Tacrolimus , Animales , Ratones , Inmunosupresores/farmacología , Metaboloma , Metabolómica
14.
Gut Microbes ; 15(2): 2291164, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38055306

RESUMEN

Bifidobacterium is a widely distributed commensal bacterial genus that displays beneficial pro-homeostatic and anti-inflammatory immunomodulatory properties. Depletion or absence of Bifidobacterium in humans and model organisms is associated with autoimmune responses and impaired immune homeostasis. At the cellular level, Bifidobacterium upregulates suppressive regulatory T cells, maintains intestinal barrier function, modulates dendritic cell and macrophage activity, and dampens intestinal Th2 and Th17 programs. While there has been a large volume of literature characterizing the probiotic properties of various Bifidobacterial species, the likely multifactorial mechanisms underlying these effects remain elusive, in particular, its immune tolerogenic effect. However, recent work has shed light on Bifidobacterium surface structural polysaccharide and protein elements, as well as its metabolic products, as commensal mediators of immune homeostasis. This review aims to discuss several mechanisms Bifidobacterium utilizes for immune modulation as well as their indirect impact on the regulation of gut microbiome structure and function, from structural molecules to produced metabolites. These mechanisms are pertinent to an increasingly networked understanding of immune tolerance and homeostasis in health and disease.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Tolerancia Inmunológica , Inmunomodulación , Bifidobacterium , Homeostasis
15.
Chest ; 164(6): e178-e179, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38070968
16.
Genet Sel Evol ; 55(1): 91, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097935

RESUMEN

BACKGROUND: The genomes of indigenous African cattle are composed of components with Middle Eastern (taurine) and South Asian (indicine) origins, providing a valuable model to study hybridization and to identify genetic barriers to gene flow. In this study, we analysed indigenous African cattle breeds as models of hybrid zones, considering taurine and indicine samples as ancestors. In a genomic cline analysis of whole-genome sequence data, we considered over 8 million variants from 144 animals, which allows for fine-mapping of potential genomic incompatibilities at high resolution across the genome. RESULTS: We identified several thousand variants that had significantly steep clines ('SCV') across the whole genome, indicating restricted introgression. Some of the SCV were clustered into extended regions, with the longest on chromosome 7, spanning 725 kb and including 27 genes. We found that variants with a high phenotypic impact (e.g. indels, intra-genic and missense variants) likely represent greater genetic barriers to gene flow. Furthermore, our findings provide evidence that a large proportion of breed differentiation in African cattle could be linked to genomic incompatibilities and reproductive isolation. Functional evaluation of genes with SCV suggest that mitonuclear incompatibilities and genes associated with fitness (e.g. resistance to paratuberculosis) could account for restricted gene flow in indigenous African cattle. CONCLUSIONS: To our knowledge, this is the first time genomic cline analysis has been applied to identify restricted introgression in the genomes of indigenous African cattle and the results provide extended insights into mechanisms (e.g. genomic incompatibilities) contributing to hybrid differentiation. These results have important implications for our understanding of genetic incompatibilities and reproductive isolation and provide important insights into the impact of cross-breeding cattle with the aim of producing offspring that are both hardy and productive.


Asunto(s)
Genoma , Genómica , Animales , Bovinos/genética , Hibridación Genética , Flujo Génico , Polimorfismo de Nucleótido Simple
17.
Res Sq ; 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-37790403

RESUMEN

Intrinsic metabolism shapes the immune environment associated with immune suppression and tolerance in settings such as organ transplantation and cancer. However, little is known about the metabolic activities in an immunosuppressive environment. In this study, we employed metagenomic, metabolomic, and immunological approaches to profile the early effects of the immunosuppressant drug tacrolimus, antibiotics, or both in gut lumen and circulation using a murine model. Tacrolimus induced rapid and profound alterations in metabolic activities within two days of treatment, prior to alterations in gut microbiota composition and structure. The metabolic profile and gut microbiome after seven days of treatment was distinct from that after two days of treatment, indicating continuous drug effects on both gut microbial ecosystem and host metabolism. The most affected taxonomic groups are Clostriales and Verrucomicrobiae (i.e., Akkermansia muciniphila), and the most affected metabolic pathways included a group of interconnected amino acids, bile acid conjugation, glucose homeostasis, and energy production. Highly correlated metabolic changes were observed between lumen and serum metabolism, supporting their significant interactions. Despite a small sample size, this study explored the largely uncharacterized microbial and metabolic events in an immunosuppressed environment and demonstrated that early changes in metabolic activities can have significant implications that may serve as antecedent biomarkers of immune activation or quiescence. To understand the intricate relationships among gut microbiome, metabolic activities, and immune cells in an immune suppressed environment is a prerequisite for developing strategies to monitor and optimize alloimmune responses that determine transplant outcomes.

18.
Front Reprod Health ; 5: 1196392, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37361343

RESUMEN

Background: The United States' (U.S.) initiative to End the HIV Epidemic aims to reduce new HIV infections in areas of high HIV prevalence. Despite national efforts to reduce HIV incidence, cisgender women continue to represent approximately one out of every five new HIV diagnoses in the U.S. Taking pre-exposure prophylaxis (PrEP) is an effective HIV prevention strategy; however, PrEP initiation among cisgender women is suboptimal, with only 10% of eligible women receiving PrEP prescriptions in 2019. Methods: We designed a trial to test the effectiveness of interventions to increase PrEP initiation, while evaluating the implementation strategy (hybrid type II trial) in seven obstetrics and gynecology (OB/GYN) clinics (two federally qualified health centers, three community-based, and two academic) in Baltimore, Maryland. A total of 42 OB/GYN providers will be enrolled and randomized (1:1:1) into one of three clinical trial arms (standard of care, patient-level intervention, or multi-level intervention). Eligible patients of enrolled providers will receive a sexual health questionnaire before their appointment through the electronic health record's (EHR) patient portal. The questionnaire will be scored in three tiers (low, moderate, and high) to assess HIV risk. Patients at low risk will be offered an HIV test only, while those who score medium or high risk will be included in the clinical trial and assigned to the clinical trial arm associated with their provider. Differences in PrEP initiation, our primary outcome, across the three arms will be analyzed using generalized linear mixed-effect models with logistic regression. We will adjust results for demographic differences observed between arms and examine PrEP initiation stratified by patient's and provider's race and ethnicity.Additionally, a comprehensive economic analysis for each intervention will be conducted. Discussion: We hypothesize that gathering information on sensitive sexual behaviors electronically, communicating HIV risk in an understandable and relatable format to patients and OB/GYN providers, and deploying EHR alerts will increase PrEP initiation and HIV testing. Trial Registration: The trial is registered with ClinicalTrials.gov (NCT05412433) on 09 June 2022. https://clinicaltrials.gov/ct2/show/NCT05412433?term=NCT05412433&draw=2&rank=1.

19.
Nat Ecol Evol ; 7(6): 903-913, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37188966

RESUMEN

Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin ~100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants.


Asunto(s)
Mariposas Diurnas , Filogenia , Animales , Evolución Biológica , Mariposas Diurnas/genética
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