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1.
AIDS Behav ; 28(5): 1795-1807, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38421512

RESUMO

Alcohol use was associated with elevated COVID-19 risk in the general population. People with HIV (PWH) have high prevalences of alcohol use. To evaluate the effect of alcohol use on COVID-19 risks among PWH, we estimated the risk of COVID-19 diagnosis and COVID-19-related hospitalization among PWH in routine care at 8 HIV primary care centers that contributed data to the Centers for AIDS Research Network of Integrated Clinical Systems (CNICS) cohort according to their alcohol use just prior to the COVID-19 pandemic. The CNICS data repository includes demographic characteristics, clinical diagnoses, and laboratory test results from electronic medical records and other sources. Alcohol use, substance use, and mental health symptoms were self-reported on tablet-based standardized surveys. Alcohol use was categorized according to standard, sex-specific Alcohol Use Disorder Identification Test-Consumption instrument cut-offs. We followed 5,496 PWH (79% male, 48% Black race, median age = 53 years) from March 1, 2020 to December 31, 2020. Relative to PWH with no baseline alcohol use, the adjusted hazard ratio (aHR) of COVID-19 diagnosis was 1.09 (95% confidence interval [CI]: 0.78, 1.51) for lower-risk drinking and 1.19 (95%CI: 0.81, 1.73) for unhealthy drinking. The aHR of COVID-19-related hospitalization was 0.82 (95%CI: 0.33, 1.99) for lower-risk drinking and 1.25 (95%CI: 0.50, 3.09) for unhealthy drinking. Results were not modified by recent cocaine or non-prescribed opioid use, depressive symptoms, or diagnoses of alcohol use disorder. The study suggested a slightly increased, but not statistically significant risk of COVID-19 diagnosis and hospitalization associated with unhealthy alcohol use.


Assuntos
Consumo de Bebidas Alcoólicas , COVID-19 , Infecções por HIV , Hospitalização , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Masculino , Feminino , Hospitalização/estatística & dados numéricos , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Fatores de Risco , Alcoolismo/epidemiologia , Prevalência
2.
J Neurooncol ; 102(2): 213-24, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20683758

RESUMO

This study was performed to determine whether low frequency ultrasound (LFU) irradiation, Papaverine (PA) infusion and combination LFU irradiation with PA infusion opened the blood-tumor barrier (BTB) by affecting tight junctions (TJ)-associated proteins zonula occluden-1 (ZO-1), occludin and caludin-5. In a rat brain glioma model, we found that the mRNA and protein expression levels of ZO-1, occludin and claudin-5 were decreased by LFU irradiation and PA infusion. LFU-induced and PA-induced decrease of ZO-1, occludin and claudin-5 was further decreased after combining LFU irradiation with PA infusion. Immunohistochemistry assay showed that the decreased expression of ZO-1, occludin and claudin-5 was the most obvious in the tumor capillaries. Meanwhile, Evans blue assay showed that the permeability of BTB was increased, and transmission electron microscopy (TEM) indicated that TJ was opened. This led to the conclusion that LFU irradiation and PA infusion together can open the BTB by paracellular pathway. Significantly down-regulated expression levels of ZO-1, occludin and claudin-5 might be one of the molecular mechanisms of combining LFU and PA enhancing the permeability of BTB.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/irrigação sanguínea , Permeabilidade Capilar/fisiologia , Glioma/irrigação sanguínea , Papaverina/uso terapêutico , Terapia por Ultrassom , Animais , Western Blotting , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Claudina-5 , Terapia Combinada , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Glioma/metabolismo , Glioma/terapia , Técnicas Imunoenzimáticas , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão , Ocludina , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Junções Íntimas , Proteína da Zônula de Oclusão-1
3.
J Neurosci Res ; 87(10): 2282-9, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19326437

RESUMO

Low-frequency ultrasound (LFU) and bradykinin (BK) have been shown separately to increase the permeability of the blood-tumor barrier (BTB) in the rat model of C6 glioma. This study examined the hypothesis that the combination of LFU and low-dose BK has a synergistic effect on increasing the permeability of BTB and explored the possible underlying mechanism including the involvement of tight junction (TJ). The rats were divided into six groups: control group, LFU group, BK group, 2/3LFU + 1/2BK group, 5/6LFU + 2/3BK group, and LFU + BK group. The BTB permeability was assessed by Evans blue extravasation. The mRNA and protein expressions of TJ-related proteins ZO-1, occludin, and claudin-5 were determined by reverse transcriptase-polymerase chain reaction, immunohistochemistry, immunolocalization, and Western blot test. BTB permeability increased in all the experimental groups, accompanied by opening of local TJ of the BTB, observed by transmission electron microscopy, and decreased mRNA and protein expressions of ZO-1, occludin, and claudin-5. In addition, there was a further increase in BTB permeability and a further reduction in the expressions of TJ-related proteins in 5/6LFU + 2/3BK and LFU + BK groups, compared with LFU or BK group. These results indicate that LFU and low-dose BK applied in combination act in a synergistic manner to increase BTB permeability. The down-regulation of TJ-related proteins ZO-1, occludin, and claudin-5 may be one of the underlying mechanisms of the increase in BTB permeability induced by LFU and BK.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Bradicinina/farmacologia , Diatermia/métodos , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/fisiologia , Vasodilatadores/farmacologia , Animais , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Barreira Hematoencefálica/ultraestrutura , Bradicinina/uso terapêutico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/terapia , Permeabilidade Capilar/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Azul Evans , Feminino , Glioma/patologia , Glioma/terapia , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão , Ocludina , Fosfoproteínas/metabolismo , Ratos , Ratos Wistar , Junções Íntimas/ultraestrutura , Proteína da Zônula de Oclusão-1
4.
J Neurooncol ; 94(1): 41-50, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19234812

RESUMO

The research was conducted to study the characteristics of the noninvasive, reversible, targeted opening of the blood-brain barrier (BBB) by use of low-frequency ultrasound (LFU) irradiation and the selective opening of the blood-tumor barrier (BTB) by intracarotid infusion of bradykinin (BK) in small-dose, with the objective of exploring maximum opening of the BTB by combining LFU irradiation with BK infusion. Thus, it provides new therapeutic strategies for targeted transport of macromolecular or granular drugs to the brain. By using the rat C6 glioma model it was shown that extravasation of Evans blue (EB) through the BTB was significantly increased by combining LFU irradiation (frequency = 1.0 MHz, power = 12 mW, duration = 20 s) with intracarotid small-dose BK infusion, compared with utilizing the two methods separately. By transmission electron microscopy (TEM) we observed that this combination significantly increased the number of pinocytotic vesicles of brain microvascular endothelial cells (BMECs) in the BTB. An even more significant increase was observed by using RT-PCR, western blot, immunohistochemistry, and immunofluorescence to detect mRNA and changes of expression of the caveolae structure proteins caveolin-1 and caveolin-2 of BMECs. In summary, this research concludes that LFU irradiation and small-dose BK together selectively enhance the permeability of the BTB and increase the number of pinocytic vesicles of BMECs to a maximum. Significant up-regulation of the level of expression of caveolae structure proteins caveolin-1 and caveolin-2 might be the molecular mechanism of the co-enhanced endocytotic transport by BMECs. Thus, this research provides new therapeutic strategies for targeted transport of macromolecular drugs and the design of drugs.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Bradicinina/farmacologia , Neoplasias Encefálicas/patologia , Glioma/patologia , Terapia por Ultrassom , Vasodilatadores/farmacologia , Animais , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/ultraestrutura , Permeabilidade Capilar/efeitos dos fármacos , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 2/genética , Caveolina 2/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Microscopia Eletrônica de Transmissão/métodos , Ratos , Ratos Wistar , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
5.
J Mol Neurosci ; 48(1): 281-90, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22528460

RESUMO

Low-frequency ultrasound (LFU) irradiation under certain acoustic intensity can increase blood-brain barrier permeability non-invasively and reversibly. The aim of this study was to find out the effect of LFU irradiation on blood-tumor barrier (BTB) permeability in rat C6 glioma model and the possible mechanism. In this research, Evans blue and H&E staining were used to evaluate the optimal parameter of LFU to open the BTB without damaging the normal brain tissue. Transmission electron microscopy was used to observe the changes of the number of pinocytotic vesicles in cerebral or glioma microvascular endothelial cells. The phosphorylation of tyrosine kinase Src, caveolin-1, and caveolin-2 was detected by western blot. The distribution and expressing levels of caveolae proteins, caveolin-1 and caveolin-2, were detected by immunohistochemical and immunofluorescent staining, RT-PCR, and western blot. Our research data showed that, in rat C6 glioma model, LFU irradiation at a frequency of 1 MHz, a power of 12 mW, and exposure time of 20 s induced the increase of BTB permeability temporally, which reached a peak at 1.5 h, then decreased and restored to normal level at 12 h after LFU irradiation. In the glioma microvascular endothelial cells of rat glioma model, LFU irradiation induced a significant increase of the pinocytotic vesicles' density. The phosphorylation of Src, caveolin-1, and caveolin-2 began to increase at 0.5 h and reached a maximum at 1 h. Immunohistochemical and immunofluorescent staining showed that caveolin-1 and caveolin-2 were co-localized in the glioma microvascular endothelial cells and glioma cells. The mRNA and protein expression levels of caveolin-1 and caveolin-2 were up-regulated, reached the peak value at 1.5 h, and re-normalized at 12 h after LFU irradiation. These results demonstrated that LFU irradiation increased BTB permeability by promoting transcellular transport in glioma microvascular endothelial cells. The phosphorylation of tyrosine kinase Src, caveolin-1, caveolin-2 and up-regulation of caveolin-1 and caveolin-2 were involved in LFU-induced caveolae-mediated endocytosis.


Assuntos
Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas , Glioma , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Permeabilidade Capilar/fisiologia , Caveolina 1/genética , Caveolina 1/metabolismo , Caveolina 2/genética , Caveolina 2/metabolismo , Linhagem Celular Tumoral , Corantes/farmacocinética , Modelos Animais de Doenças , Endocitose/fisiologia , Azul Evans/farmacocinética , Feminino , Glioma/irrigação sanguínea , Glioma/diagnóstico por imagem , Glioma/terapia , Transplante de Neoplasias , Fosforilação/fisiologia , Pinocitose/fisiologia , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Ultrassonografia , Quinases da Família src/metabolismo
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