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1.
Int J Infect Dis ; 146: 107121, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38823622

RESUMO

OBJECTIVES: To investigate multi-dose and timings of COVID-19 vaccines in preventing antenatal infection. DESIGN: Prospective observational study investigating primary vaccinations, boosters, antenatal COVID-19 infections, neutralizing antibody (Nab) durability, and cross-reactivity to Delta and Omicron variants of concern (VOCs). RESULTS: Ninety-eight patients completed primary vaccination prepregnancy (29.6%) and antenatally (63.3%), 24.2% of whom had antenatal COVID-19, while 7.1% were unvaccinated (28.6% had antenatal COVID-19). None had severe COVID-19. Prepregnancy vaccination resulted in vaccination-to-infection delay of 23.3 weeks, which extended to 45.2 weeks with a booster, compared to 16.9 weeks following antenatal vaccination (P < 0.001). Infections occurred at 26.2 weeks gestation in women vaccinated prepregnancy compared to 36.2 weeks gestation in those vaccinated during pregnancy (P < 0.007). The risk of COVID-19 infection was higher without antenatal vaccination (hazard ratio [HR] 14.6, P = 0.05) and after prepregnancy vaccination without a booster (HR 10.4, P = 0.002). Antenatal vaccinations initially led to high Nab levels, with mild waning but subsequent rebound. Significant Nab enhancement occurred with a third-trimester booster. Maternal-neonatal Nab transfer was efficient (transfer ratio >1), and cross-reactivity to VOCs was observed. CONCLUSION: Completing vaccination during any trimester delays COVID-19 infection and maintains effective neutralizing activity throughout pregnancy, with robust cross-reactivity to VOCs and efficient maternal-neonatal transfer.

2.
Anticancer Drugs ; 29(1): 50-60, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29023248

RESUMO

Acid ceramidase is the key enzyme of the ceramide metabolic pathway, which plays a vital role in regulating ceramide - sphingosine-1-phosphate rheostat. Ceramide acts as a proapoptotic molecule, but its metabolite sphingosine-1-phosphate, in contrast, signals for cell proliferation, cell survival, and angiogenesis. Acid ceramidase is highly upregulated in breast tumors and treatment with an acid ceramidase inhibitor, ceranib-2, significantly induced apoptosis in human breast cancer cell lines. However, the mechanisms underlying the induction of apoptosis remain ambiguous to date. Hence, in the present study, we have explored ceranib-2-mediated apoptotic signaling pathways in human breast cancer cell lines. MCF-7 and MDA MB-231 cells were treated with IC50 doses of ceranib-2 and tamoxifen. Nuclear changes showed the apoptotic effect of ceranib-2 in both the cell lines. Loss in the mitochondrial membrane potential was observed only in ceranib-2-treated MCF-7 cells. Ceranib-2 activated intrinsic and extrinsic apoptotic pathways in MCF-7 cells, but only the extrinsic apoptotic pathway was activated in MDA MB-231 cells. Further, ceranib-2 induced apoptosis by activating SAPK/JNK (stress-activated protein kinase/c-Jun N-terminal kinase), p38 MAPK (mitogen-activated protein kinase) apoptotic pathways and by inhibiting the Akt (antiapoptotic) pathway in both the cell lines. Most importantly, ERα (estrogen receptor-α) expression was highly downregulated after ceranib-2 treatment and a docking study predicted the highest binding affinity of ceranib-2 than tamoxifen with ERα in MCF-7 cells. Hence, ceranib-2 may have potential as a chemotherapeutic drug of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Quinolonas/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Humanos , MAP Quinase Quinase 4/antagonistas & inibidores , MAP Quinase Quinase 4/metabolismo , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tamoxifeno/farmacologia
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