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1.
Nature ; 617(7959): 139-146, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37076617

RESUMO

Loss of the PTEN tumour suppressor is one of the most common oncogenic drivers across all cancer types1. PTEN is the major negative regulator of PI3K signalling. The PI3Kß isoform has been shown to play an important role in PTEN-deficient tumours, but the mechanisms underlying the importance of PI3Kß activity remain elusive. Here, using a syngeneic genetically engineered mouse model of invasive breast cancer driven by ablation of both Pten and Trp53 (which encodes p53), we show that genetic inactivation of PI3Kß led to a robust anti-tumour immune response that abrogated tumour growth in syngeneic immunocompetent mice, but not in immunodeficient mice. Mechanistically, PI3Kß inactivation in the PTEN-null setting led to reduced STAT3 signalling and increased the expression of immune stimulatory molecules, thereby promoting anti-tumour immune responses. Pharmacological PI3Kß inhibition also elicited anti-tumour immunity and synergized with immunotherapy to inhibit tumour growth. Mice with complete responses to the combined treatment displayed immune memory and rejected tumours upon re-challenge. Our findings demonstrate a molecular mechanism linking PTEN loss and STAT3 activation in cancer and suggest that PI3Kß controls immune escape in PTEN-null tumours, providing a rationale for combining PI3Kß inhibitors with immunotherapy for the treatment of PTEN-deficient breast cancer.


Assuntos
Evasão da Resposta Imune , Neoplasias Mamárias Animais , PTEN Fosfo-Hidrolase , Fosfatidilinositol 3-Quinase , Animais , Camundongos , Imunoterapia , Fosfatidilinositol 3-Quinase/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , Transdução de Sinais , Neoplasias Mamárias Animais/enzimologia , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/imunologia , Neoplasias Mamárias Experimentais/enzimologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/imunologia
2.
Occup Med (Lond) ; 71(2): 105-108, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33598680

RESUMO

BACKGROUND: The annual influenza vaccination is recommended for all front-line healthcare workers in the UK and is a crucial way of reducing mortality for vulnerable patient groups. However, to date the UK government has never explicitly monitored influenza vaccine uptake in medical students. This is important to ascertain, as students regularly move between clinical areas and are both a perfect vector for the spread of influenza and at an increased risk of contracting influenza themselves. AIMS: This service evaluation was designed to evaluate the effectiveness of an influenza vaccination programme in one UK medical school and make recommendations to increase vaccination rates in the future. METHODS: This service evaluation collected data about medical student uptake of influenza vaccination in one UK medical school. Two hundred and fifty-one students at different course stages completed questionnaires, answering questions on vaccination status and Likert-scale 'belief' questions to assess the subjective reasons behind vaccine refusal. RESULTS: There was a substantial difference between year group cohorts (~20%), with significantly higher vaccination rates in the preclinical year group. Two significant negative predictors of vaccination were found (P < 0.001), related to scepticism over the effectiveness of the vaccine and lack of convenient access to the vaccination. Results indicated that integrating information about the influenza vaccine into the curriculum would reduce lack of knowledge over the efficacy of the vaccine. The centralization of vaccination programmes at mandatory university-based learning events would mitigate against the problem of diversity of vaccination locations and lack of central accountability. CONCLUSIONS: The results of this service evaluation provide significant predictors of vaccination status for medical students and potential occupational health interventions to improve vaccine uptake in this group.


Assuntos
Vacinas contra Influenza , Influenza Humana , Estudantes de Medicina , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Influenza Humana/prevenção & controle , Inquéritos e Questionários , Reino Unido , Vacinação
3.
Clin Exp Immunol ; 198(1): 83-93, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31119724

RESUMO

Activation of the innate immune response following myocardial infarction (MI) is essential for infarct repair. Preclinical models of MI commonly use C57BL/6 mice, which have a type 1-dominant immune response, whereas other mouse strains such as BALB/c mice have a type 2-dominant immune response. We compared C57BL/6 and BALB/c mice to investigate whether predisposition towards a proinflammatory phenotype influences the dynamics of the innate immune response to MI and associated infarct healing and the risk of cardiac rupture. MI was induced by permanent coronary artery ligation in 12-15-week-old male wild-type BALB/c and C57BL/6 mice. Prior to MI, C57BL/6 mice had a lower proportion of CD206+ anti-inflammatory macrophages in the heart and an expanded blood pool of proinflammatory Ly6Chigh monocytes in comparison to BALB/c mice. The systemic inflammatory response in C57BL/6 mice following MI was more pronounced, with greater peripheral blood Ly6Chigh monocytosis, splenic Ly6Chigh monocyte mobilization and myeloid cell infiltration of pericardial adipose tissue. This led to an increased and prolonged macrophage accumulation, as well as delayed transition towards anti-inflammatory macrophage polarization in the infarct zone and surrounding tissues of C57BL/6 mice. These findings accompanied a higher rate of mortality due to cardiac rupture in C57BL/6 mice compared with BALB/c mice. We conclude that lower post-MI survival of C57BL/6 mice over BALB/c mice is mediated in part by a more pronounced and prolonged inflammatory response. Outcomes in BALB/c mice highlight the therapeutic potential of modulating resolution of the innate immune response following MI for the benefit of successful infarct healing.


Assuntos
Macrófagos/imunologia , Monócitos/imunologia , Infarto do Miocárdio/imunologia , Cicatrização/imunologia , Animais , Vasos Coronários/imunologia , Genótipo , Inflamação/imunologia , Ativação de Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Células Mieloides/imunologia , Miocárdio/imunologia , Fenótipo
4.
Glia ; 66(5): 987-998, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29380422

RESUMO

Previously, we determined microRNA-31 (miR-31) is a noncoding tumor suppressive gene frequently deleted in glioblastoma (GBM); miR-31 suppresses tumor growth, in part, by limiting the activity of NF-κB. Herein, we expand our previous studies by characterizing the role of miR-31 during neural precursor cell (NPC) to astrocyte differentiation. We demonstrate that miR-31 expression and activity is suppressed in NPCs by stem cell factors such as Lin28, c-Myc, SOX2 and Oct4. However, during astrocytogenesis, miR-31 is induced by STAT3 and SMAD1/5/8, which mediate astrocyte differentiation. We determined miR-31 is required for terminal astrocyte differentiation, and that the loss of miR-31 impairs this process and/or prevents astrocyte maturation. We demonstrate that miR-31 promotes astrocyte development, in part, by reducing the levels of Lin28, a stem cell factor implicated in NPC renewal. These data suggest that miR-31 deletions may disrupt astrocyte development and/or homeostasis.


Assuntos
Astrócitos/metabolismo , Diferenciação Celular/fisiologia , MicroRNAs/metabolismo , Células-Tronco Neurais/metabolismo , Animais , Células Cultivadas , Imunofluorescência , Immunoblotting , Hibridização In Situ , Camundongos Endogâmicos C57BL , Proteínas de Ligação a RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Xenopus laevis
5.
AIDS Behav ; 22(2): 569-579, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28589504

RESUMO

Youth represent a large proportion of new HIV infections worldwide, yet their utilization of HIV testing and counseling (HTC) remains low. Using the post-intervention, cross-sectional, population-based household survey done in 2011 as part of HPTN 043/NIMH Project Accept, a cluster-randomized trial of community mobilization and mobile HTC in South Africa (Soweto and KwaZulu Natal), Zimbabwe, Tanzania and Thailand, we evaluated age-related differences among socio-demographic and behavioral determinants of HTC in study participants by study arm, site, and gender. A multivariate logistic regression model was developed using complete individual data from 13,755 participants with recent HIV testing (prior 12 months) as the outcome. Youth (18-24 years) was not predictive of recent HTC, except for high-risk youth with multiple concurrent partners, who were less likely (aOR 0.75; 95% CI 0.61-0.92) to have recently been tested than youth reporting a single partner. Importantly, the intervention was successful in reaching men with site specific success ranging from aOR 1.27 (95% CI 1.05-1.53) in South Africa to aOR 2.30 in Thailand (95% CI 1.85-2.84). Finally, across a diverse range of settings, higher education (aOR 1.67; 95% CI 1.42, 1.96), higher socio-economic status (aOR 1.21; 95% CI 1.08-1.36), and marriage (aOR 1.55; 95% CI 1.37-1.75) were all predictive of recent HTC, which did not significantly vary across study arm, site, gender or age category (18-24 vs. 25-32 years).


Assuntos
Aconselhamento , Infecções por HIV/diagnóstico , Programas de Rastreamento/estatística & dados numéricos , Parceiros Sexuais , Adolescente , Adulto , Fatores Etários , Estudos Transversais , Feminino , Infecções por HIV/prevenção & controle , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Fatores Socioeconômicos , África do Sul , Tanzânia , Tailândia , Adulto Jovem , Zimbábue
6.
Int J Obes (Lond) ; 41(11): 1693-1701, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28792489

RESUMO

OBJECTIVE: High-protein diets (HPDs) are associated with greater satiety and weight loss than diets rich in other macronutrients. The exact mechanisms by which HPDs exert their effects are unclear. However, evidence suggests that the sensing of amino acids produced as a result of protein digestion may have a role in appetite regulation and satiety. We investigated the effects of l-phenylalanine (L-Phe) on food intake and glucose homeostasis in rodents. METHODS: We investigated the effects of the aromatic amino-acid and calcium-sensing receptor (CaSR) agonist l-phenylalanine (L-Phe) on food intake and the release of the gastrointestinal (GI) hormones peptide YY (PYY), glucagon-like peptide-1 (GLP-1) and ghrelin in rodents, and the role of the CaSR in mediating these effects in vitro and in vivo. We also examined the effect of oral l-Phe administration on glucose tolerance in rats. RESULTS: Oral administration of l-Phe acutely reduced food intake in rats and mice, and chronically reduced food intake and body weight in diet-induced obese mice. Ileal l-Phe also reduced food intake in rats. l-Phe stimulated GLP-1 and PYY release, and reduced plasma ghrelin, and also stimulated insulin release and improved glucose tolerance in rats. Pharmacological blockade of the CaSR attenuated the anorectic effect of intra-ileal l-Phe in rats, and l-Phe-induced GLP-1 release from STC-1 and primary L cells was attenuated by CaSR blockade. CONCLUSIONS: l-Phe reduced food intake, stimulated GLP-1 and PYY release, and reduced plasma ghrelin in rodents. Our data provide evidence that the anorectic effects of l-Phe are mediated via the CaSR, and suggest that l-Phe and the CaSR system in the GI tract may have therapeutic utility in the treatment of obesity and diabetes. Further work is required to determine the physiological role of the CaSR in protein sensing in the gut, and the role of this system in humans.


Assuntos
Depressores do Apetite/farmacologia , Regulação do Apetite/efeitos dos fármacos , Hormônios Gastrointestinais/metabolismo , Intolerância à Glucose , Fenilalanina/farmacologia , Receptores de Detecção de Cálcio/metabolismo , Saciação/efeitos dos fármacos , Animais , Depressores do Apetite/administração & dosagem , Modelos Animais de Doenças , Ingestão de Alimentos/efeitos dos fármacos , Metabolismo Energético , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenilalanina/administração & dosagem , Ratos , Ratos Wistar , Receptores dos Hormônios Gastrointestinais/metabolismo
7.
Am J Physiol Heart Circ Physiol ; 309(4): H702-10, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26071543

RESUMO

The extent of infarct injury is a key determinant of structural and functional remodeling following myocardial infarction (MI). Infarct volume in experimental models of MI can be determined accurately by in vivo magnetic resonance imaging (MRI), but this is costly and not widely available. Experimental studies therefore commonly assess injury by histological analysis of sections sampled from the infarcted heart, an approach that is labor intensive, can be subjective, and does not fully assess the extent of injury. The present study aimed to assess the suitability of optical projection tomography (OPT) for identification of injured myocardium and for accurate and efficient assessment of infarct volume. Intact, perfusion-fixed, optically cleared hearts, collected from mice 7 days after induction of MI by coronary artery occlusion, were scanned by a tomograph for autofluorescence emission after UV excitation, generating >400 transaxial sections for reconstruction. Differential autofluorescence permitted discrimination between viable and injured myocardium and highlighted the heterogeneity within the infarct zone. Two-dimensional infarct areas derived from OPT imaging and Masson's trichrome staining of slices from the same heart were highly correlated (r(2) = 0.99, P < 0.0001). Infarct volume derived from reconstructed OPT sections correlated with volume derived from in vivo late gadolinium enhancement MRI (r(2) = 0.7608, P < 0.005). Tissue processing for OPT did not compromise subsequent immunohistochemical detection of endothelial cell and inflammatory cell markers. OPT is thus a nondestructive, efficient, and accurate approach for routine in vitro assessment of murine myocardial infarct volume.


Assuntos
Infarto do Miocárdio/patologia , Tomografia Óptica , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sensibilidade e Especificidade
8.
Phys Rev Lett ; 114(6): 065502, 2015 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-25723227

RESUMO

A basic tenet of material science is that the flow stress of a metal increases as its grain size decreases, an effect described by the Hall-Petch relation. This relation is used extensively in material design to optimize the hardness, durability, survivability, and ductility of structural metals. This Letter reports experimental results in a new regime of high pressures and strain rates that challenge this basic tenet of mechanical metallurgy. We report measurements of the plastic flow of the model body-centered-cubic metal tantalum made under conditions of high pressure (>100 GPa) and strain rate (∼10(7) s(-1)) achieved by using the Omega laser. Under these unique plastic deformation ("flow") conditions, the effect of grain size is found to be negligible for grain sizes >0.25 µm sizes. A multiscale model of the plastic flow suggests that pressure and strain rate hardening dominate over the grain-size effects. Theoretical estimates, based on grain compatibility and geometrically necessary dislocations, corroborate this conclusion.


Assuntos
Modelos Teóricos , Tantálio/química , Teste de Materiais/métodos , Metais/química , Tamanho da Partícula
9.
S Afr Med J ; 114(7): e1597, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39041521

RESUMO

BACKGROUND: In the absence of more recent national data on underlying causes of death in South Africa (SA), we examined mortality trends from 2010 to 2022 among members of a large private medical scheme. This analysis sheds light on the health profile of this specific demographic. OBJECTIVE: To investigate trends in Discovery Health Medical Scheme (DHMS) members' death rates and underlying cause of death patterns between 2010 and 2022. METHODS: All-cause deaths were compared across years accounting for demographic changes, by analysing age- and sex-standardised rates using 2019 age and sex population weightings. We used underlying cause-of-death data from death notifications. RESULTS: The 2019 age- and sex-standardised death rate was lower than the 2010 rate by 10%, with a steady decline experienced between 2010 and 2019. We have seen reduced age- and sex-standardised death rates from HIV/AIDS during this period, and despite the high prevalence, reduced age- and sex-standardised death rates from non-communicable diseases. Malignant neoplasms and cardiovascular disease have been and remained the two leading causes of death for Discovery Health Medical Scheme (DHMS) clients between 2012 and 2022. Age- and sex- standardised death rates, however, reached historic high levels during the first 2 years of the COVID-19 pandemic in SA. In 2020, overall age- and sex-standardised death rates for DHMS members increased to 542 deaths per 100 000 life years, which was higher than pre-pandemic levels. Age- and sex-standardised death rates went on to reach their highest level in the history of the scheme in 2021, at 767 deaths per 100 000 life years. Age- and sex-standardised death rates, however, had returned to near 2019 (pre-pandemic) levels by 2022, at 477 deaths per 100 000 life years. Males experienced a higher increase in age-standardised death rates during 2020 and remained at an increased risk of death in 2022 compared with pre-pandemic levels. When COVID-19 -related deaths are excluded, the age-standardised rates for both females and males in 2022 was lower than observed in the pre-pandemic years. While the low mortality experience could be related to competing causes and mortality displacement, further analysis over a longer period is needed to confirm this. CONCLUSION: DHMS experienced the highest level of age- and sex-standardised death rates during 2020 and 2021, the initial 2 years of the COVID-19 pandemic. Most of this increase was explained by COVID-19 deaths.


Assuntos
COVID-19 , Causas de Morte , Humanos , África do Sul/epidemiologia , Masculino , Feminino , Causas de Morte/tendências , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Lactente , Idoso , Pré-Escolar , Criança , COVID-19/mortalidade , COVID-19/epidemiologia , Mortalidade/tendências , Recém-Nascido , Idoso de 80 Anos ou mais , Distribuição por Sexo
10.
Expert Opin Drug Saf ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115010

RESUMO

INTRODUCTION: Despite the public health success of vaccination, there is an ongoing need to build public confidence in vaccines and improve systems to monitor safety while maintaining data security and patient privacy. African countries face multiple challenges in establishing systems for vaccine pharmacovigilance as was demonstrated during COVID-19 mass vaccination. We provide a framework for the development of pharmacovigilance using the COVID-19 vaccination roll-out as an exemplar. AREAS COVERED: We describe the pre-COVID-19 vaccine pharmacovigilance systems in Southern Africa and propose improvements based on our experience of COVID-19 vaccine roll-out in South Africa where we implemented systems to evaluate real-world safety and effectiveness of COVID-19 vaccinations. By conducting a pubmed review of the literature on pharmacovigilance with a focus on Africa and from guidance emanating from the World Health Organisation (WHO), we evaluate challenges and opportunities to improve pharmacovigilance in our setting. EXPERT OPINION: There are ongoing efforts to improve pharmacovigilance on the African continent with improved coordination at a national level with the support of WHO, the national regulatory authorities, and national departments of health. COVID-19 vaccine roll-out provided an opportunity to improve pharmacovigilance by integrating national vaccine platforms with active and passive surveillance including hospital and death registries.

11.
Microbiol Resour Announc ; 13(8): e0053224, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39012130

RESUMO

Because fluorinated organic compounds are broadly used and highly persistent, microbes isolated from wastewater may be able to degrade these contaminants. Here, we report the genome sequences of Flavobacterium sp. str. WV_118_3, Nocardioides sp. str. WV_118_6, Ochrobactrum anthropi str. WV_118_8, and Sphingomonas sp. str. VL_57B, isolated from wastewater.

12.
Nat Commun ; 15(1): 2003, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443359

RESUMO

Airborne transmission of SARS-CoV-2 aerosol remains contentious. Importantly, whether cough or breath-generated bioaerosols can harbor viable and replicating virus remains largely unclarified. We performed size-fractionated aerosol sampling (Andersen cascade impactor) and evaluated viral culturability in human cell lines (infectiousness), viral genetics, and host immunity in ambulatory participants with COVID-19. Sixty-one percent (27/44) and 50% (22/44) of participants emitted variant-specific culture-positive aerosols <10µm and <5µm, respectively, for up to 9 days after symptom onset. Aerosol culturability is significantly associated with lower neutralizing antibody titers, and suppression of transcriptomic pathways related to innate immunity and the humoral response. A nasopharyngeal Ct <17 rules-in ~40% of aerosol culture-positives and identifies those who are probably highly infectious. A parsimonious three transcript blood-based biosignature is highly predictive of infectious aerosol generation (PPV > 95%). There is considerable heterogeneity in potential infectiousness i.e., only 29% of participants were probably highly infectious (produced culture-positive aerosols <5µm at ~6 days after symptom onset). These data, which comprehensively confirm variant-specific culturable SARS-CoV-2 in aerosol, inform the targeting of transmission-related interventions and public health containment strategies emphasizing improved ventilation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Cinética , Aerossóis e Gotículas Respiratórios
13.
Nat Commun ; 15(1): 6152, 2024 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-39034312

RESUMO

Cells rely on antioxidants to survive. The most abundant antioxidant is glutathione (GSH). The synthesis of GSH is non-redundantly controlled by the glutamate-cysteine ligase catalytic subunit (GCLC). GSH imbalance is implicated in many diseases, but the requirement for GSH in adult tissues is unclear. To interrogate this, we have developed a series of in vivo models to induce Gclc deletion in adult animals. We find that GSH is essential to lipid abundance in vivo. GSH levels are highest in liver tissue, which is also a hub for lipid production. While the loss of GSH does not cause liver failure, it decreases lipogenic enzyme expression, circulating triglyceride levels, and fat stores. Mechanistically, we find that GSH promotes lipid abundance by repressing NRF2, a transcription factor induced by oxidative stress. These studies identify GSH as a fulcrum in the liver's balance of redox buffering and triglyceride production.


Assuntos
Glutamato-Cisteína Ligase , Glutationa , Fígado , Fator 2 Relacionado a NF-E2 , Triglicerídeos , Animais , Glutationa/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fígado/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Glutamato-Cisteína Ligase/genética , Camundongos , Triglicerídeos/metabolismo , Estresse Oxidativo , Masculino , Metabolismo dos Lipídeos , Camundongos Knockout , Camundongos Endogâmicos C57BL , Oxirredução , Lipogênese/genética
14.
Genes Immun ; 14(1): 42-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23151487

RESUMO

Two CCL3 haplotypes (HapA1 and Hap-A3) and two polymorphic positions shared by the haplotypes (Hap-2SNP (single nucleotide polymorphism)) were investigated together with CCL3L copy number (CN), for their role in HIV-1 disease. Hap-A1 was associated with protection from in utero HIV-1 infection: exposed uninfected (EU) infants had higher representation of wild type (WT)/Hap-A1 than infected infants (excluding intrapartum (IP)-infected infants), which maintained significance post maternal Nevirapine (mNVP) and viral load (MVL) correction (P=0.04; odds ratio (OR)=0.33). Mother-infant pair analyses showed the protective effect of Hap-A1 is dependent on its presence in the infant. Hap-A3 was associated with increased IP transmission: WT/Hap-A3 was increased in IP-transmitting vs non-transmitting (NT) mothers, and remained significant post mNVP and MVL correction (P=0.02; OR=3.50). This deleterious effect of Hap-A3 seemed dependent on its presence in the mother. Hap-2SNP was associated with lower CD4 count in the NT mothers (P=0.03). CCL3 Hap-A1 was associated with high CCL3L CN in total (P=0.001) and EU infants (P=0.006); the effect was not additive, however, having either Hap-A1 or high CCL3L CN was more significantly (P=0.0008) associated with protection from in utero infection than Hap-A1 (P=0.028) or high CCL3L CN (P=0.002) alone. Linkage disequilibrium between Hap-A1 and high CCL3L CN appears unlikely given that a Nigerian population showed an opposite relationship.


Assuntos
Quimiocina CCL3/genética , Dosagem de Genes , Infecções por HIV/genética , Infecções por HIV/transmissão , HIV-1 , Haplótipos , África Subsaariana/epidemiologia , Fármacos Anti-HIV/uso terapêutico , Antígenos CD4/sangue , Feminino , Predisposição Genética para Doença , Infecções por HIV/tratamento farmacológico , Infecções por HIV/virologia , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas , Desequilíbrio de Ligação , Nevirapina/uso terapêutico , Polimorfismo de Nucleotídeo Único , Carga Viral
15.
N Engl J Med ; 362(5): 427-39, 2010 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-20089951

RESUMO

BACKGROUND: Most persons who are infected with human immunodeficiency virus type 1 (HIV-1) are also infected with herpes simplex virus type 2 (HSV-2), which is frequently reactivated and is associated with increased plasma and genital levels of HIV-1. Therapy to suppress HSV-2 reduces the frequency of reactivation of HSV-2 as well as HIV-1 levels, suggesting that suppression of HSV-2 may reduce the risk of transmission of HIV-1. METHODS: We conducted a randomized, placebo-controlled trial of suppressive therapy for HSV-2 (acyclovir at a dose of 400 mg orally twice daily) in couples in which only one of the partners was seropositive for HIV-1 (CD4 count, > or = 250 cells per cubic millimeter) and that partner was also infected with HSV-2 and was not taking antiretroviral therapy at the time of enrollment. The primary end point was transmission of HIV-1 to the partner who was not initially infected with HIV-1; linkage of transmissions was assessed by means of genetic sequencing of viruses. RESULTS: A total of 3408 couples were enrolled at 14 sites in Africa. Of the partners who were infected with HIV-1, 68% were women, and the baseline median CD4 count was 462 cells per cubic millimeter. Of 132 HIV-1 seroconversions that occurred after randomization (an incidence of 2.7 per 100 person-years), 84 were linked within couples by viral sequencing: 41 in the acyclovir group and 43 in the placebo group (hazard ratio with acyclovir, 0.92, 95% confidence interval [CI], 0.60 to 1.41; P=0.69). Suppression with acyclovir reduced the mean plasma concentration of HIV-1 by 0.25 log(10) copies per milliliter (95% CI, 0.22 to 0.29; P<0.001) and the occurrence of HSV-2-positive genital ulcers by 73% (risk ratio, 0.27; 95% CI, 0.20 to 0.36; P<0.001). A total of 92% of the partners infected with HIV-1 and 84% of the partners not infected with HIV-1 remained in the study for 24 months. The level of adherence to the dispensed study drug was 96%. No serious adverse events related to acyclovir were observed. CONCLUSIONS: Daily acyclovir therapy did not reduce the risk of transmission of HIV-1, despite a reduction in plasma HIV-1 RNA of 0.25 log(10) copies per milliliter and a 73% reduction in the occurrence of genital ulcers due to HSV-2. (ClinicalTrials.gov number, NCT00194519.)


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Infecções por HIV/transmissão , HIV-1 , Herpes Genital/tratamento farmacológico , Herpesvirus Humano 2 , Aciclovir/efeitos adversos , Adolescente , Adulto , Antivirais/efeitos adversos , Contagem de Linfócito CD4 , Feminino , Seguimentos , Infecções por HIV/complicações , HIV-1/genética , HIV-1/isolamento & purificação , Herpes Genital/complicações , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Cooperação do Paciente , Gravidez , RNA Viral/sangue , Sexo sem Proteção/estatística & dados numéricos , Adulto Jovem
16.
Sex Transm Infect ; 89(6): 467-72, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23785040

RESUMO

BACKGROUND: Human trichomoniasis is the most common non-viral sexually transmitted disease, yet immune responses are not well studied. METHODS: Since the Trichomonas vaginalis lipophosphoglycan (TvLPG) is an important virulence factor, a bank of eight monoclonal antibodies was generated to define the antigen in clinical isolates. The TvLPG-specific antibody response of women who were culture positive (n=33) or negative (n=33) for T vaginalis infection was determined by isotype-specific ELISA. RESULTS: The bank of monoclonal antibodies reacted with conserved surface TvLPG epitopes in 27 isolates from pregnant women at their first prenatal visit. Conserved TvLPG epitopes were shown to be surface exposed by immunofluorescence. Sera collected from the same patients at the same time were assayed for specific antibodies. Serum and vaginal secretions from 33 T vaginalis-positive women had statistically higher IgG anti-TvLPG levels than age-matched and race-matched negative controls in the same clinical study (p<0.01). Vaginal IgA anti-TvLPG levels of the women with trichomoniasis were almost significantly higher than controls (p=0.055). Infected women with normal pregnancies had significantly higher vaginal IgG anti-TvLPG values than infected women with adverse outcomes of pregnancy. CONCLUSIONS: These antibody responses show that infected women can respond to the conserved TvLPG antigen. Since antibodies to trichomonad surface LPG protect in a bovine model of trichomoniasis, the role of these antibodies in the human disease should be investigated.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Glicolipídeos/imunologia , Tricomoníase/imunologia , Trichomonas vaginalis/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/isolamento & purificação , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Estudos Prospectivos
17.
Cell Rep ; 42(10): 113293, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37858468

RESUMO

Although distinct epithelial cell types have been distinguished in glandular tissues such as the mammary gland, the extent of heterogeneity within each cell type and the degree of endocrine control of this diversity across development are incompletely understood. By combining mass cytometry and cyclic immunofluorescence, we define a rich array of murine mammary epithelial cell subtypes associated with puberty, the estrous cycle, and sex. These subtypes are differentially proliferative and spatially segregate distinctly in adult versus pubescent glands. Further, we identify systematic suppression of lineage programs at the protein and RNA levels as a common feature of mammary epithelial expansion during puberty, the estrous cycle, and gestation and uncover a pervasive enrichment of ribosomal protein genes in luminal cells elicited specifically during progesterone-dominant expansionary periods. Collectively, these data expand our knowledge of murine mammary epithelial heterogeneity and connect endocrine-driven epithelial expansion with lineage suppression.


Assuntos
Sinais (Psicologia) , Glândulas Mamárias Animais , Camundongos , Animais , Glândulas Mamárias Animais/metabolismo , RNA/metabolismo , Proliferação de Células , Análise Espacial , Células Epiteliais/metabolismo
18.
Nat Commun ; 14(1): 5206, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37626143

RESUMO

Germline BRCA2 mutation carriers frequently develop luminal-like breast cancers, but it remains unclear how BRCA2 mutations affect mammary epithelial subpopulations. Here, we report that monoallelic Brca2mut/WT mammary organoids subjected to replication stress activate a transcriptional response that selectively expands Brca2mut/WT luminal cells lacking hormone receptor expression (HR-). While CyTOF analyses reveal comparable epithelial compositions among wildtype and Brca2mut/WT mammary glands, Brca2mut/WT HR- luminal cells exhibit greater organoid formation and preferentially survive and expand under replication stress. ScRNA-seq analysis corroborates the expansion of HR- luminal cells which express elevated transcript levels of Tetraspanin-8 (Tspan8) and Thrsp, plus pathways implicated in replication stress survival including Type I interferon responses. Notably, CRISPR/Cas9-mediated deletion of Tspan8 or Thrsp prevents Brca2mut/WT HR- luminal cell expansion. Our findings indicate that Brca2mut/WT cells activate a transcriptional response after replication stress that preferentially favours outgrowth of HR- luminal cells through the expression of interferon-responsive and mammary alveolar genes.


Assuntos
Células Epiteliais , Interferon Tipo I , Proliferação de Células , Ciclo Celular , Expressão Gênica
19.
J Clin Oncol ; 41(35): 5335-5344, 2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38056080

RESUMO

PURPOSE: We developed and validated a brief, yet sensitive, 33-item general cancer quality-of-life (QL) measure for evaluating patients receiving cancer treatment, called the Functional Assessment of Cancer Therapy (FACT) scale. METHODS AND RESULTS: The five-phase validation process involved 854 patients with cancer and 15 oncology specialists. The initial pool of 370 overlapping items for breast, lung, and colorectal cancer was generated by open-ended interview with patients experienced with the symptoms of cancer and oncology professionals. Using preselected criteria, items were reduced to a 38-item general version. Factor and scaling analyses of these 38 items on 545 patients with mixed cancer diagnoses resulted in the 28-item FACT-general (FACT-G, version 2). In addition to a total score, this version produces subscale scores for physical, functional, social, and emotional well-being, as well as satisfaction with the treatment relationship. Coefficients of reliability and validity were uniformly high. The scale's ability to discriminate patients on the basis of stage of disease, performance status rating (PSR), and hospitalization status supports its sensitivity. It has also demonstrated sensitivity to change over time. Finally, the validity of measuring separate areas, or dimensions, of QL was supported by the differential responsiveness of subscales when applied to groups known to differ along the dimensions of physical, functional, social, and emotional well-being. CONCLUSION: The FACT-G meets or exceeds all requirements for use in oncology clinical trials, including ease of administration, brevity, reliability, validity, and responsiveness to clinical change. Selecting it for a clinical trial adds the capability to assess the relative weight of various aspects of QL from the patient's perspective.

20.
bioRxiv ; 2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36798186

RESUMO

Cells rely on antioxidants to survive. The most abundant antioxidant is glutathione (GSH). The synthesis of GSH is non-redundantly controlled by the glutamate-cysteine ligase catalytic subunit (GCLC). GSH imbalance is implicated in many diseases, but the requirement for GSH in adult tissues is unclear. To interrogate this, we developed a series of in vivo models to induce Gclc deletion in adult animals. We find that GSH is essential to lipid abundance in vivo. GSH levels are reported to be highest in liver tissue, which is also a hub for lipid production. While the loss of GSH did not cause liver failure, it decreased lipogenic enzyme expression, circulating triglyceride levels, and fat stores. Mechanistically, we found that GSH promotes lipid abundance by repressing NRF2, a transcription factor induced by oxidative stress. These studies identify GSH as a fulcrum in the liver's balance of redox buffering and triglyceride production.

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