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1.
Cell ; 187(2): 464-480.e10, 2024 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-38242088

RESUMO

Primary open-angle glaucoma (POAG), the leading cause of irreversible blindness worldwide, disproportionately affects individuals of African ancestry. We conducted a genome-wide association study (GWAS) for POAG in 11,275 individuals of African ancestry (6,003 cases; 5,272 controls). We detected 46 risk loci associated with POAG at genome-wide significance. Replication and post-GWAS analyses, including functionally informed fine-mapping, multiple trait co-localization, and in silico validation, implicated two previously undescribed variants (rs1666698 mapping to DBF4P2; rs34957764 mapping to ROCK1P1) and one previously associated variant (rs11824032 mapping to ARHGEF12) as likely causal. For individuals of African ancestry, a polygenic risk score (PRS) for POAG from our mega-analysis (African ancestry individuals) outperformed a PRS from summary statistics of a much larger GWAS derived from European ancestry individuals. This study quantifies the genetic architecture similarities and differences between African and non-African ancestry populations for this blinding disease.


Assuntos
Estudo de Associação Genômica Ampla , Glaucoma de Ângulo Aberto , Humanos , Predisposição Genética para Doença , Glaucoma de Ângulo Aberto/genética , População Negra/genética , Polimorfismo de Nucleotídeo Único/genética
2.
Nat Immunol ; 19(5): 475-486, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29670239

RESUMO

CD4+ T lymphocytes are the principal target of human immunodeficiency virus (HIV), but infected macrophages also contribute to viral pathogenesis. The killing of infected cells by CD8+ cytotoxic T lymphocytes (CTLs) leads to control of viral replication. Here we found that the killing of macrophages by CTLs was impaired relative to the killing of CD4+ T cells by CTLs, and this resulted in inefficient suppression of HIV. The killing of macrophages depended on caspase-3 and granzyme B, whereas the rapid killing of CD4+ T cells was caspase independent and did not require granzyme B. Moreover, the impaired killing of macrophages was associated with prolonged effector cell-target cell contact time and higher expression of interferon-γ by CTLs, which induced macrophage production of pro-inflammatory chemokines that recruited monocytes and T cells. Similar results were obtained when macrophages presented other viral antigens, suggestive of a general mechanism for macrophage persistence as antigen-presenting cells that enhance inflammation and adaptive immunity. Inefficient killing of macrophages by CTLs might contribute to chronic inflammation, a hallmark of chronic disease caused by HIV.


Assuntos
Linfócitos T CD4-Positivos/virologia , Citotoxicidade Imunológica/imunologia , Infecções por HIV/imunologia , Macrófagos/virologia , Linfócitos T Citotóxicos/imunologia , Células Cultivadas , Humanos
3.
Immunity ; 54(10): 2372-2384.e7, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34496223

RESUMO

Spontaneous control of HIV infection has been repeatedly linked to antiviral CD8+ T cells but is not always permanent. To address mechanisms of durable and aborted control of viremia, we evaluated immunologic and virologic parameters longitudinally among 34 HIV-infected subjects with differential outcomes. Despite sustained recognition of autologous virus, HIV-specific proliferative and cytolytic T cell effector functions became selectively and intrinsically impaired prior to aborted control. Longitudinal transcriptomic profiling of functionally impaired HIV-specific CD8+ T cells revealed altered expression of genes related to activation, cytokine-mediated signaling, and cell cycle regulation, including increased expression of the antiproliferative transcription factor KLF2 but not of genes associated with canonical exhaustion. Lymphoid HIV-specific CD8+ T cells also exhibited poor functionality during aborted control relative to durable control. Our results identify selective functional impairment of HIV-specific CD8+ T cells as prognostic of impending aborted HIV control, with implications for clinical monitoring and immunotherapeutic strategies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Viremia/imunologia , Viremia/virologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva
4.
J Neurosci ; 44(23)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38697841

RESUMO

Interneurons in the medial prefrontal cortex (PFC) regulate local neural activity to influence cognitive, motivated, and emotional behaviors. Parvalbumin-expressing (PV+) interneurons are the primary mediators of thalamus-evoked feed-forward inhibition across the mouse cortex, including the anterior cingulate cortex, where they are engaged by inputs from the mediodorsal (MD) thalamus. In contrast, in the adjacent prelimbic (PL) cortex, we find that PV+ interneurons are scarce in the principal thalamorecipient layer 3 (L3), suggesting distinct mechanisms of inhibition. To identify the interneurons that mediate MD-evoked inhibition in PL, we combine slice physiology, optogenetics, and intersectional genetic tools in mice of both sexes. We find interneurons expressing cholecystokinin (CCK+) are abundant in L3 of PL, with cells exhibiting fast-spiking (fs) or non-fast-spiking (nfs) properties. MD inputs make stronger connections onto fs-CCK+ interneurons, driving them to fire more readily than nearby L3 pyramidal cells and other interneurons. CCK+ interneurons in turn make inhibitory, perisomatic connections onto L3 pyramidal cells, where they exhibit cannabinoid 1 receptor (CB1R) mediated modulation. Moreover, MD-evoked feed-forward inhibition, but not direct excitation, is also sensitive to CB1R modulation. Our findings indicate that CCK+ interneurons contribute to MD-evoked inhibition in PL, revealing a mechanism by which cannabinoids can modulate MD-PFC communication.


Assuntos
Colecistocinina , Interneurônios , Inibição Neural , Córtex Pré-Frontal , Animais , Interneurônios/fisiologia , Colecistocinina/metabolismo , Córtex Pré-Frontal/fisiologia , Camundongos , Masculino , Feminino , Inibição Neural/fisiologia , Tálamo/fisiologia , Camundongos Endogâmicos C57BL , Parvalbuminas/metabolismo , Camundongos Transgênicos , Vias Neurais/fisiologia , Optogenética
5.
Small ; 20(23): e2307529, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38174594

RESUMO

Acoustic microfluidic devices have advantages for diagnostic applications, therapeutic solutions, and fundamental research due to their contactless operation, simple design, and biocompatibility. However, most acoustofluidic approaches are limited to forming simple and fixed acoustic patterns, or have limited resolution. In this study,a detachable microfluidic device is demonstrated employing miniature acoustic holograms to create reconfigurable, flexible, and high-resolution acoustic fields in microfluidic channels, where the introduction of a solid coupling layer makes these holograms easy to fabricate and integrate. The application of this method to generate flexible acoustic fields, including shapes, characters, and arbitrarily rotated patterns, within microfluidic channels, is demonstrated.

6.
Pharm Res ; 41(4): 751-763, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38443633

RESUMO

PURPOSE: To evaluate the clinical feasibility and tolerability of large volume subcutaneous delivery at different injection depths for lean and non-lean subjects. METHODS: A single-center, randomized, subject-blinded, crossover study in 62 healthy subjects was conducted to evaluate delivery of a 10-cP solution containing hyaluronic acid. Subjects were separated into lean and non-lean cohort by SC thickness. A syringe pump was used to study the effect of different volumes (5, 12, 25 mL) of a viscous placebo solution and needle lengths (6, 9 and 12 mm) delivered at 0.5 mL/min. RESULTS: Across all treatments, injection sites were observed to have negligible leakage, ~34 kPa of back pressure, and VAS of mild pain with higher pain from needle insertion than during injection. While mild to moderate erythema was the most frequently reported ISR and edema was most prominent for 25 mL injections, all ISRs were resolved within 4 hours post injection. Subjects were unbothered by ISRs across all treatments and rated them as low distress scores (average 1.0-1.5 out of 6). CONCLUSION: SC injection of 25 mL is feasible and tolerable using a low-pain formulation for abdomen injection irrespective of subcutaneous thickness and injection depths at a delivery rate of 0.5 mL/min.


Assuntos
Dor , Tela Subcutânea , Humanos , Injeções Subcutâneas , Estudos Cross-Over , Dor/tratamento farmacológico
7.
BMC Womens Health ; 24(1): 392, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38978020

RESUMO

BACKGROUND: Cervical cancer screening uptake remains low despite being a critical prevention method for adult women living with HIV(WLHIV). These women experience greater incidence and persistence of high-risk human papillomavirus (HPV) and severe outcomes, including cervical cancer comorbidity and death. OBJECTIVE: We explored the opportunities, challenges, and recommendations of clinical care providers and WLHIV to improve cervical cancer screening uptake among WLHIV in Southwestern Uganda. METHODS: In a cross-sectional qualitative study from January to June 2021 at Mbarara Regional Referral Hospital, we interviewed six key informant clinical care providers and held four focus group discussions with women living with HIV. Data was coded using Atlas ti software and analysed using thematic inductive analysis. RESULTS: The participants identified several prevailing opportunities for cervical cancer screening, including skilled clinical care workers, public awareness for demand creation, optimized clinic flow, provider-led referrals, and peer-led information sharing that ease clinic navigation and shorten participant throughput. However, challenges occurred due to standalone services resulting in double queuing, longer clinic visit hours, missed chances for screening alongside unsupported lower health facilities leading to crowding at the referral hospital, and inadequate patient privacy measures leading to shame and stigma and the misconception that cervical cancer is incurable. Integrating HPV-DNA testing in HIV services was perceived with ambivalence; some participants worried about the quality of sample collection, while others valued the privacy it offered. Optimising self-collected DNA testing and sufficient counselling were recommended to improve cervical cancer screening uptake. CONCLUSION: Opportunities for cervical cancer screening included trained clinical care professionals, increased public awareness, improved clinic flow, provider referrals, and peer education. Challenges, such as unsupported lower-level health facilities, misconceptions, inadequate patient privacy, and uncertainty about integrating HPV-DNA screening into HIV services, were cited. Adequate counselling and self-sample collection were recommended to foster screening. Our findings may guide healthcare programs integrating cervical cancer screening into HIV clinics to reach the 70% World Health Organisation targets by 2030.


Assuntos
Detecção Precoce de Câncer , Grupos Focais , Infecções por HIV , Pesquisa Qualitativa , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico , Infecções por HIV/diagnóstico , Detecção Precoce de Câncer/métodos , Adulto , Uganda , Estudos Transversais , Pessoa de Meia-Idade , Encaminhamento e Consulta , Programas de Rastreamento/métodos , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/complicações
8.
BMC Biol ; 21(1): 153, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430246

RESUMO

BACKGROUND: The standard evolutionary theory of ageing proposes that ageing occurs because of a trade-off between reproduction and longevity. Eusocial insect queens exhibit positive fecundity-longevity associations and so have been suggested to be counter-examples through not expressing costs of reproduction and through remodelling conserved genetic and endocrine networks regulating ageing and reproduction. If so, eusocial evolution from solitary ancestors with negative fecundity-longevity associations must have involved a stage at which costs of reproduction were suppressed and fecundity and longevity became positively associated. Using the bumblebee (Bombus terrestris), we experimentally tested whether queens in annual eusocial insects at an intermediate level of eusocial complexity experience costs of reproduction, and, using mRNA-seq, the extent to which they exhibit a remodelling of relevant genetic and endocrine networks. Specifically, we tested whether costs of reproduction are present but latent, or whether a remodelling of relevant genetic and endocrine networks has already occurred allowing queens to reproduce without costs. RESULTS: We experimentally increased queens' costs of reproduction by removing their eggs, which caused queens to increase their egg-laying rate. Treatment queens had significantly reduced longevity relative to control queens whose egg-laying rate was not increased. Reduced longevity in treatment queens was not caused by increased worker-to-queen aggression or by increased overall activity in queens. In addition, treatment and control queens differed in age-related gene expression based on mRNA-seq in both their overall expression profiles and the expression of ageing-related genes. Remarkably, these differences appeared to occur principally with respect to relative age, not chronological age. CONCLUSIONS: This study represents the first simultaneously phenotypic and transcriptomic experimental test for a longevity cost of reproduction in eusocial insect queens. The results support the occurrence of costs of reproduction in annual eusocial insects of intermediate social complexity and suggest that reproductive costs are present but latent in queens of such species, i.e. that these queens exhibit condition-dependent positive fecundity-longevity associations. They also raise the possibility that a partial remodelling of genetic and endocrine networks underpinning ageing may have occurred in intermediately eusocial species such that, in unmanipulated conditions, age-related gene expression depends more on chronological than relative age.


Assuntos
Fertilidade , Reprodução , Abelhas/genética , Animais , Envelhecimento , Longevidade , RNA Mensageiro
9.
BMC Womens Health ; 23(1): 572, 2023 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932705

RESUMO

BACKGROUND: Abnormal vaginal discharge is a common complaint among women of reproductive age, affecting about one- third of all women. In resource-limited settings where access to laboratory services is limited, treatment is usually syndromic. This approach may result in ineffective treatment, with high recurrence rates and a potential of developing antibiotic resistance. This study aimed to determine the bacterial isolates and antibiotic susceptibility among women with an abnormal vaginal discharge attending the gynecology clinic at a tertiary hospital in Southwestern Uganda. METHODS: We conducted a hospital based cross-sectional study among 361 women aged 15-49 years, presenting with abnormal vaginal discharge at the gynecology clinic of Mbarara Regional Referral Hospital from December 2020 to June 2021. Demographic characteristics were collected using a structured questionnaire. We collected cervical and vaginal sterile swabs and subjected them to wet preparation and gram stain. The specimens were cultured for bacterial isolates. Susceptibility testing was performed on samples with bacterial isolates using the Kirby-Bauer disc diffusion method, on the commonly prescribed antibiotics in this setting. We summarized and described the bacterial isolates and antibiotic susceptibility patterns as frequencies and percentages. RESULTS: We enrolled 361 women with abnormal vaginal discharge. Bacteria were isolated in 29.6% (107/361) of the women, and the commonest isolates included; Staphylococcus aureus 48.6% (52/107), Klebsiella pneumoniae 29.9% (32/107) and Enterococcus faecalis 15% (16/107). Yeast cells were found in 17.7% (64/361) of the women with abnormal vaginal discharge. Cefuroxime (90.7%) and Ciprofloxacin (81.3%) had a high level of sensitivity while high levels of resistance were observed for Doxycycline (86.0%) and Azithromycin (67.0%). CONCLUSION: The common bacterial isolates were Staphylococcus aureus, Klebsiella pneumoniae and Enterococcus faecalis. The isolated bacteria were most sensitive to Cefuroxime and Ciprofloxacin but resistant to Doxycycline and Azithromycin. There is need for routine culture and susceptibility testing of women with abnormal vaginal discharge so as to guide treatment, minimize inappropriate antibiotic use and consequently reduce antibiotic resistance.


Assuntos
Antibacterianos , Bactérias , Infecções Bacterianas , Descarga Vaginal , Feminino , Humanos , Antibacterianos/uso terapêutico , Estudos Transversais , Testes de Sensibilidade Microbiana , Centros de Atenção Terciária , Uganda , Descarga Vaginal/tratamento farmacológico , Descarga Vaginal/microbiologia , Resistência Microbiana a Medicamentos , Infecções Bacterianas/tratamento farmacológico , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação
10.
Proc Natl Acad Sci U S A ; 117(38): 23835-23846, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900948

RESUMO

Nef is an HIV-encoded accessory protein that enhances pathogenicity by down-regulating major histocompatibility class I (MHC-I) expression to evade killing by cytotoxic T lymphocytes (CTLs). A potent Nef inhibitor that restores MHC-I is needed to promote immune-mediated clearance of HIV-infected cells. We discovered that the plecomacrolide family of natural products restored MHC-I to the surface of Nef-expressing primary cells with variable potency. Concanamycin A (CMA) counteracted Nef at subnanomolar concentrations that did not interfere with lysosomal acidification or degradation and were nontoxic in primary cell cultures. CMA specifically reversed Nef-mediated down-regulation of MHC-I, but not CD4, and cells treated with CMA showed reduced formation of the Nef:MHC-I:AP-1 complex required for MHC-I down-regulation. CMA restored expression of diverse allotypes of MHC-I in Nef-expressing cells and inhibited Nef alleles from divergent clades of HIV and simian immunodeficiency virus, including from primary patient isolates. Lastly, we found that restoration of MHC-I in HIV-infected cells was accompanied by enhanced CTL-mediated clearance of infected cells comparable to genetic deletion of Nef. Thus, we propose CMA as a lead compound for therapeutic inhibition of Nef to enhance immune-mediated clearance of HIV-infected cells.


Assuntos
HIV-1 , Interações Hospedeiro-Patógeno , Macrolídeos , Linfócitos T Citotóxicos , Células Cultivadas , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/imunologia , Humanos , Macrolídeos/imunologia , Macrolídeos/farmacologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/virologia , Produtos do Gene nef do Vírus da Imunodeficiência Humana
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