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1.
Cell Rep ; 42(5): 112503, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: covidwho-2311643

RESUMEN

Striking antibody evasion by emerging circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants drives the identification of broadly neutralizing antibodies (bNAbs). However, how a bNAb acquires increased neutralization breadth during antibody evolution is still elusive. Here, we identify a clonally related antibody family from a convalescent individual. One of the members, XG005, exhibits potent and broad neutralizing activities against SARS-CoV-2 variants, while the other members show significant reductions in neutralization breadth and potency, especially against the Omicron sublineages. Structural analysis visualizing the XG005-Omicron spike binding interface reveals how crucial somatic mutations endow XG005 with greater neutralization potency and breadth. A single administration of XG005 with extended half-life, reduced antibody-dependent enhancement (ADE) effect, and increased antibody product quality exhibits a high therapeutic efficacy in BA.2- and BA.5-challenged mice. Our results provide a natural example to show the importance of somatic hypermutation during antibody evolution for SARS-CoV-2 neutralization breadth and potency.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Ratones , Anticuerpos , Anticuerpos ampliamente neutralizantes , Mutación/genética , Anticuerpos Antivirales , Anticuerpos Neutralizantes
2.
Int J Mol Sci ; 23(14)2022 Jul 08.
Artículo en Inglés | MEDLINE | ID: covidwho-1964000

RESUMEN

Acetaminophen (APAP) is a widely used antipyretic analgesic which can lead to acute liver failure after overdoses. Chronic alcoholic fatty liver disease (AFLD) appears to enhance the risk and severity of APAP-induced liver injury, and the level of angiotensin II (Ang II) increased sharply at the same time. However, the underlying mechanisms remain unclear. Caveolin-1 (CAV1) has been proven to have a protective effect on AFLD. This study aimed to examine whether CAV1 can protect the APAP-induced hepatotoxicity of AFLD by affecting Ang II or its related targets. In vivo, the AFLD model was established according to the chronic-plus-binge ethanol model. Liver injury and hepatic lipid accumulation level were determined. The levels of Angiotensin converting enzyme 2 (ACE2), Ang II, CAV1, and other relevant proteins were evaluated by western blotting. In vitro, L02 cells were treated with alcohol and oleic acid mixture and APAP. CAV1 and ACE2 expression was downregulated in APAP-treated AFLD mice compared to APAP-treated mice. The overexpression of CAV1 in mice and L02 cells alleviated APAP-induced hepatotoxicity in AFLD and downregulated Ang II, p-EGFR/EGFR and P-ERK/ERK expression. Immunofluorescence experiments revealed interactions between CAV1, Ang II, and EGFR. The application of losartan (an Ang II receptor antagonist) and PD98059 (an ERK1/2 inhibitor) alleviated APAP-induced hepatotoxicity in AFLD. In conclusion, our findings verified that CAV1 alleviates APAP-aggravated hepatotoxicity in AFLD by downregulating the Ang II /EGFR/ERK axis, which could be a novel therapeutic target for its prevention or treatment.


Asunto(s)
Caveolina 1 , Enfermedad Hepática Inducida por Sustancias y Drogas , Hígado Graso Alcohólico , Acetaminofén/efectos adversos , Angiotensina II/metabolismo , Enzima Convertidora de Angiotensina 2 , Animales , Caveolina 1/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Receptores ErbB/metabolismo , Hígado Graso Alcohólico/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL
3.
Pakistan Journal of Medical Sciences Quarterly ; 38(5):1243, 2022.
Artículo en Inglés | ProQuest Central | ID: covidwho-1918771

RESUMEN

Objectives: To evaluate the clinical value of intravesical gemcitabine combined with immunotherapy in patients with non-muscle-invasive bladder carcinoma (NMIBC) after transurethral resection of bladder tumor (TURBT). Methods: Eighty patients with non-muscle-invasive urothelial carcinoma treated in Baoding No.1 Hospital from November 2016 to November 2019 were randomly divided into two groups, with 40 patients in each group. Both groups underwent TURBT. After surgery, the research group was treated with intravesical chemotherapy using gemcitabine combined with ubenimex, while the control group was given 40 mg pirarubicin by intravesical instillation. Postoperative condition was evaluated by cystoscopy every three months in both groups. The recurrence six months, one year and two years after treatment, the incidence of lower urinary tract symptoms such as dysuria, hematuria and frequent urination, general adverse drug reactions such as rashes, liver function damage and gastrointestinal reaction, as well as the changes in CD3+, CD4+, CD8+ and CD4+/CD8+ T lymphocyte subsets before and after treatment were comparatively analyzed between the two groups. Results: The recurrence rate showed no statistical significance between the two groups 6 months after treatment (p=0.17), but significant differences one year (p=0.04) and two years (p=0.03) after treatment, which were significantly lower in the research group than the control group. The incidence of adverse drug reactions was 22.5% in the research group and 7.5% in the control group, without significant difference (p=0.36). The incidence of lower urinary tract symptoms was 32.5% and 55%, respectively, in the research group and the control group. The incidence of lower urinary tract symptoms in the research group was significantly lower compared with the control group, with a statistically significant difference (p=0.04). After treatment, CD3+, CD4+ and CD4+/CD8+ levels in the research group increased significantly than those in the control group, with statistically significant differences (CD3+, p=0.01;CD4+, p=0.00;CD4+/CD8+, p=0.00). Conclusions: For NMIBC patients receiving bladder-preserving surgery, intravesical gemcitabine combined with immunotherapy can reduce the recurrence rate, relieve lower urinary tract symptoms, increase the tolerance of patients to intravesical chemotherapy and significantly improve the function of T lymphocytes, without obvious increase in adverse drug reactions. Therefore, it is safe and effective, and has certain clinical value.

4.
Ann Transl Med ; 10(4): 166, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: covidwho-1737500

RESUMEN

Background: The present study aimed to analyze the impact of frailty on mortality risk among hospitalized patients with coronavirus disease 2019 (COVID-19). Methods: Literature searches were conducted using the MEDLINE, Embase, and Cochrane databases for articles reporting the association between frailty and mortality in hospitalized patients with COVID-19. The quality of the included studies was assessed using the Newcastle-Ottawa scale (NOS). A random-effects meta-analysis was performed to calculate the pooled effects. Results: A total of 21 studies with 26,652 hospitalized patients were included. Sixteen studies used the Clinical Frailty Score (CFS), and five used other frailty assessment tools. The pooled estimates of frailty in hospitalized patients with COVID-19 were 51.4% [95% confidence interval (CI): 39.9-62.9%]. In the CFS group, frail patients experienced a higher rate of short-term mortality than non-frail patients [odds ratio (OR) =3.0; 95% CI: 2.3-3.9; I2=72.7%; P<0.001]. In the other tools group, frail patients had a significantly increased short-term mortality risk compared with non-frail patients (OR =2.4; 95% CI: 1.4-4.1; P=0.001). Overall, a higher short-term mortality risk was observed for frail patients than non-frail patients (OR =2.8; 95% CI: 2.3-3.5; P<0.001). In older adults, frail patients had a higher rate of short-term mortality than non-frail patients (OR =2.3; 95% CI: 1.8-2.9; P<0.001). Conclusions: Compared to non-frail hospitalized patients with COVID-19, frail patients suffered a higher risk of all-cause mortality, and this result was also found in the older adult group.

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