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1.
Microbiol Spectr ; 11(4): e0400022, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37458590

RESUMO

Prochlorococcus and Synechococcus are the two dominant picocyanobacteria in the low-nutrient surface waters of the subtropical ocean, but the basis for their coexistence has not been quantitatively demonstrated. Here, we combine in situ microcosm experiments and an ecological model to show that this coexistence can be sustained by specialization in the uptake of distinct nitrogen (N) substrates at low-level concentrations that prevail in subtropical environments. In field incubations, the response of both Prochlorococcus and Synechococcus to nanomolar N amendments demonstrates N limitation of growth in both populations. However, Prochlorococcus showed a higher affinity to ammonium, whereas Synechococcus was more adapted to nitrate uptake. A simple ecological model demonstrates that the differential nutrient preference inferred from field experiments with these genera may sustain their coexistence. It also predicts that as the supply of NO3- decreases, as expected under climate warming, the dominant genera should undergo a nonlinear shift from Synechococcus to Prochlorococcus, a pattern that is supported by subtropical field observations. Our study suggests that the evolution of differential nutrient affinities is an important mechanism for sustaining the coexistence of genera and that climate change is likely to shift the relative abundance of the dominant plankton genera in the largest biomes in the ocean. IMPORTANCE Our manuscript addresses the following fundamental question in microbial ecology: how do different plankton using the same essential nutrients coexist? Prochlorococcus and Synechococcus are the two dominant picocyanobacteria in the low-nutrient surface waters of the subtropical ocean, which support a significant amount of marine primary production. The geographical distributions of these two organisms are largely overlapping, but the basis for their coexistence in these biomes remains unclear. In this study, we combined in situ microcosm experiments and an ecosystem model to show that the coexistence of these two organisms can arise from specialization in the uptake of distinct nitrogen substrates; Prochlorococcus prefers ammonium, whereas Synechococcus prefers nitrate when these nutrients exist at low concentrations. Our framework can be used for simulating and predicting the coexistence in the future ocean and may provide hints toward understanding other similar types of coexistence.


Assuntos
Compostos de Amônio , Synechococcus , Fitoplâncton , Ecossistema , Água do Mar/microbiologia , Nitratos , Nitrogênio
3.
Liver Cancer ; 12(2): 156-170, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37325489

RESUMO

Introduction: Atezolizumab plus bevacizumab treatment is highly effective in patients with unresectable hepatocellular carcinoma (HCC). However, progressive disease (PD) occurs in approximately 20% of HCC patients treated with atezolizumab plus bevacizumab, resulting in a poor prognosis. Thus, the prediction and early detection of HCC is crucial. Methods: Patients with unresectable HCC treated with atezolizumab plus bevacizumab and had baseline preserved serum (n = 68) were screened and classified according to their PD, 6 weeks after treatment initiation (early PD; n = 13). Of these, 4 patients each with and without early PD were selected for cytokine array and genetic analyses. The identified factors were validated in the validated cohort (n = 60) and evaluated in patients treated with lenvatinib. Results: No significant differences were observed in the genetic alterations in circulating tumor DNA. Cytokine array data revealed that baseline MIG (CXCL9), ENA-78, and RANTES differed substantially between patients with and without early PD. Subsequent analysis in the validation cohort revealed that baseline CXCL9 was significantly lower in patients with early PD than that in patients without early PD, and the best cut-off value of serum CXCL9 to predict early PD was 333 pg/mL (sensitivity: 0.600, specificity: 0.923, AUC = 0.75). In patients with lower serum CXCL9 (<333 pg/mL), 35.3% (12/34) experienced early PD with atezolizumab plus bevacizumab, while progression-free survival (PFS) was significantly shorter relative to that in patients without (median PFS, 126 days vs. 227 days; HR: 2.41, 95% CI: 1.22-4.80, p = 0.0084). While patients with objective response to lenvatinib had significantly lower CXCL9 levels compared with those of patients without. Conclusion: Baseline low serum CXCL9 (<333 pg/mL) levels may predict early PD in patients with unresectable HCC treated with atezolizumab plus bevacizumab.

4.
Jpn J Infect Dis ; 76(5): 275-281, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37121673

RESUMO

Adverse events are potentially associated with an IgG response after BNT162b2 vaccination for severe acute respiratory syndrome coronavirus 2. In this study, we investigated the side effects of the BNT162b2 vaccine using a health questionnaire and examined its relationship with IgG antibody titers. Serum samples were collected from participants 3 months after the second vaccination, immediately before the third vaccination, and 1 and 3 months after the third vaccination. A total of 505 participants who received three doses of vaccine were eligible for inclusion in the analysis. The results showed that post-vaccination body temperature correlated with anti-spike-receptor-binding domain (anti-S-RBD) antibody titers measured 3 months after the second (r = 0.30, P < 0.001) and third (r = 0.14, P < 0.001) vaccinations. Multivariate linear regression analysis revealed that age and severe swelling were negatively associated, whereas female sex, body temperature, and heat sensation were positively associated with log-transformed anti-S-RBD antibody levels after the second vaccination. After the third vaccination, body temperature and fatigue were positively associated, and female sex was negatively associated, with the log-transformed anti-S-RBD antibody levels. These results suggest that post-vaccination fever may be a marker of a high antibody titer.


Assuntos
Vacina BNT162 , COVID-19 , Febre , Feminino , Humanos , Anticorpos Antivirais/sangue , Vacina BNT162/efeitos adversos , COVID-19/prevenção & controle , Imunoglobulina G/sangue , Japão , Vacinação/efeitos adversos , Febre/induzido quimicamente
5.
J Med Virol ; 95(2): e28452, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36597900

RESUMO

No prospective study on the efficacy of tenofovir alafenamide (TAF), a novel tenofovir prodrug, in preventing hepatitis B virus (HBV) reactivation has yet been reported. This multicenter prospective study enrolled HBV-carriers who received TAF to prevent HBV reactivation before antitumor or immunosuppressive therapy, and patients with resolved HBV infection who experienced HBV-reactivation and received TAF to prevent HBV reactivation-related hepatitis. The efficacy of prophylactic TAF in preventing HBV reactivation and HBV reactivation-related hepatitis was evaluated at 6 and 12 months after initiating TAF. Overall, 110 patients were administered TAF to prevent HBV reactivation or HBV reactivation-related hepatitis. Three patients died owing to primary disease, whereas one patient was transferred to another hospital within 6 months after initiating TAF. Seven patients died due to primary disease, and five patients were transferred to another hospital within 12 months after initiating TAF. Therefore, 106 and 94 (77 patients with HBV infection, 17 with previous-HBV infection) patients were evaluated at 6 and 12 months after initiating TAF, respectively. No patient experienced HBV reactivation, HBV reactivation-related hepatitis, or treatment discontinuation due to HBV reactivation or adverse events of TAF after 6 and 12 months. TAF could effectively prevent HBV reactivation and HBV reactivation-related hepatitis.


Assuntos
Hepatite A , Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B , Antivirais/uso terapêutico , Alanina/uso terapêutico , Adenina/efeitos adversos , Hepatite B Crônica/tratamento farmacológico
6.
Viruses ; 15(1)2023 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-36680221

RESUMO

Progressive liver fibrosis after anti-HCV treatment is a risk factor for HCC. Angiopoietin-2 (Ang2) is associated with non-regression of liver fibrosis after direct-acting antiviral (DAA). This study evaluated the predictive value of serum Ang2 levels for HCC occurrence or recurrence after DAA administration. In this retrospective study, 310 HCV-infected patients treated with DAAs in 2014-2020 were screened and evaluated for HCC occurrence or recurrence every three-six months. Multivariate Cox regression analysis revealed that age ≥ 75 years (HR: 2.92, 95% CI: 1.34-6.33; p = 0.007) and baseline Ang2 level ≥ 464 pg/mL (HR: 2.75, 95% CI: 1.18-6.37; p = 0.019) were significantly associated with HCC occurrence after DAA therapy. A high or low risk of HCC after DAA therapy could be distinguished by the combination of age and baseline Ang2 level. The cumulative incidences of de-novo HCC at two and four years were 0.8% and 3.8% in the low-risk group and 22.6% and 27.1% in the high-risk group, respectively. Baseline Ang2 level ≥ 402 pg/mL was significantly associated with HCC recurrence in patients who achieved sustained virological response with DAAs (HR: 3.68). In conclusion, serum Ang2 levels can predict HCC occurrence and recurrence after successful HCV eradication by DAAs.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/tratamento farmacológico , Antivirais/uso terapêutico , Neoplasias Hepáticas/etiologia , Estudos Retrospectivos , Angiopoietina-2/uso terapêutico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepacivirus/genética , Fatores de Risco , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/complicações
7.
Cancers (Basel) ; 14(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36010930

RESUMO

The IMbrave150 trial demonstrated the high efficacy and safety of atezolizumab and bevacizumab for unresectable hepatocellular carcinoma (HCC). In this multicenter study, the efficacy of this combination and its effect on liver functional reserve were evaluated in patients not meeting the eligibility criteria of IMbrave150. Of 115 patients with unresectable HCC treated with atezolizumab and bevacizumab between October 2020 and January 2022, 72 did not meet the eligibility criteria of IMbrave150, most frequently due to a history of systemic therapy (60/72), platelet counts < 75 × 109/L (7/72), Child-Pugh B (9/72), and 2+ proteinuria (8/72). Atezolizumab and bevacizumab therapy was equally effective for patients who did or did not meet the eligibility criteria (PFS, 6.5 vs. 6.9 months, p = 0.765), consistent with subgroup analyses of histories of systemic therapy, platelet counts, Child-Pugh, and proteinuria. Baseline ALBI scores were worse in patients who did not meet the criteria than in those who did and significantly worsened after treatment initiation in patients not meeting the criteria (baseline vs. 12 weeks; 2.35 ± 0.43 vs. −2.18 ± 0.54; p = 0.007). Accordingly, atezolizumab plus bevacizumab was effective for patients not meeting the eligibility criteria of IMbrave150, although careful monitoring for changes in liver functional reserve is needed.

8.
Microbiol Spectr ; 10(4): e0217721, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35770981

RESUMO

Crocosphaera watsonii (hereafter referred to as Crocosphaera) is a key nitrogen (N) fixer in the ocean, but its ability to consume combined-N sources is still unclear. Using in situ microcosm incubations with an ecological model, we show that Crocosphaera has high competitive capability both under low and moderately high combined-N concentrations. In field incubations, Crocosphaera accounted for the highest consumption of ammonium and nitrate, followed by picoeukaryotes. The model analysis shows that cells have a high ammonium uptake rate (~7 mol N [mol N]-1 d-1 at the maximum), which allows them to compete against picoeukaryotes and nondiazotrophic cyanobacteria when combined N is sufficiently available. Even when combined N is depleted, their capability of nitrogen fixation allows higher growth rates compared to potential competitors. These results suggest the high fitness of Crocosphaera in combined-N limiting, oligotrophic oceans heightening its potential significance in its ecosystem and in biogeochemical cycling. IMPORTANCE Crocosphaera watsonii is as a key nitrogen (N) supplier in marine ecosystems, and it has been estimated to contribute up to half of oceanic N2 fixation. Conversely, a recent study reported that Crocosphaera can assimilate combined N and proposed that unicellular diazotrophs can be competitors with non-N2 fixing phytoplankton for combined N. Despite its importance in nitrogen cycling, the methods by which Crocosphaera compete are not currently fully understood. Here, we present a new role of Crocosphaera as a combined-N consumer: a competitor against nondiazotrophic phytoplankton for combined N. In this study, we combined in situ microcosm experiments and an ecosystem model to quantitatively evaluate the combined-N consumption by Crocosphaera and other non-N2 fixing phytoplankton. Our results suggest the high fitness of Crocosphaera in combined-N limiting, oligotrophic oceans and, thus, heightens its potential significance in its ecosystem and in biogeochemical cycling.


Assuntos
Compostos de Amônio , Cianobactérias , Ecossistema , Nitrogênio , Água do Mar
9.
Sci Rep ; 12(1): 1449, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35087141

RESUMO

Liver stiffness measurement (LSM) is a useful tool for assessing advanced liver fibrosis, an important risk factor for hepatocellular carcinoma (HCC) following hepatitis C (HCV) eradication. This study aimed to clarify the non-invasive factors associated with HCC following sustained virological response (SVR) and to identify the low-risk group. 567 patients without history of HCC who achieved SVR at 24 weeks (SVR24) after IFN-free treatment were retrospectively analyzed. The cumulative incidence of HCC and the risk factors were examined using pre-treatment and SVR24 data. The median observation period was 50.2 months. Thirty cases of HCC were observed, and the 4-year cumulative incidence of HCC was 5.9%. In multivariate analysis, significant pre-treatment factors were age ≥ 71 years (hazard ratio [HR]: 3.402) and LSM ≥ 9.2 kPa (HR: 6.328); SVR24 factors were age ≥ 71 years (HR: 2.689) and LSM ≥ 8.4 kPa (HR: 6.642). In cases with age < 71 years and LSM < 8.4 kPa at the time of SVR24, the 4-year cumulative incidence of HCC was as low as 1.1%. Both pre-treatment LSM (≥ 9.2 kPa) and SVR24 LSM (≥ 8.4 kPa) and age (≥ 71 years) are useful in predicting the risk of HCC after SVR with IFN-free treatment. Identification of low-risk individuals may improve the efficiency of follow-up.


Assuntos
Carcinoma Hepatocelular/epidemiologia , Técnicas de Imagem por Elasticidade/estatística & dados numéricos , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Fígado/diagnóstico por imagem , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antivirais/uso terapêutico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Quimioterapia Combinada/métodos , Quimioterapia Combinada/estatística & dados numéricos , Feminino , Seguimentos , Hepacivirus/isolamento & purificação , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/patologia , Hepatite C Crônica/virologia , Humanos , Incidência , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Resposta Viral Sustentada , Adulto Jovem
10.
Sci Rep ; 11(1): 22472, 2021 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795343

RESUMO

The liver-spleen contrast (LSC) using hepatobiliary-phase images could replace the receptor index (LHL15) in liver scintigraphy; however, few comparative studies exist. This study aimed to verify the convertibility from LSC into LHL15. In 136 patients, the LSC, not at 20 min, but at 60 min after injecting gadolinium-ethoxybenzyl-diethylenetriaminepentaacetic acid was compared with the LHL15, albumin-bilirubin (ALBI) score, and the related laboratory parameters. The LHL15 was also compared with their biochemical tests. The correlation coefficients of LSC with LHL15, ALBI score, total bilirubin, and albumin were 0.740, -0.624, -0.606, and 0.523 (P < 0.00001), respectively. The correlation coefficients of LHL15 with ALBI score, total bilirubin, and albumin were -0.647, -0.553, and 0.569 (P < 0.00001), respectively. The linear regression equation on the estimated LHL15 (eLHL15) from LSC was eLHL15 = 0.460 · LSC + 0.727 (P < 0.00001) and the coefficient of determination was 0.548. Regarding a contingency table using imaging-based clinical stage classification, the degree of agreement between eLHL15 and LHL15 was 65.4%, and Cramer's V was 0.568 (P < 0.00001). Therefore, although the LSC may be influenced by high total bilirubin, the eLHL15 can replace the LSC as an index to evaluate liver function.


Assuntos
Gadolínio DTPA/química , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Cintilografia/métodos , Baço/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Albuminas/análise , Bilirrubina/análise , Meios de Contraste , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X
11.
Hepatol Res ; 51(9): 979-989, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34245216

RESUMO

AIM: A clinical trial (IMbrave150) indicated the efficacy and safety of atezolizumab plus bevacizumab for patients with unresectable hepatocellular carcinoma (HCC). In this study, we evaluated this therapeutic combination in a real-world setting, with a focus on patients who did not meet the IMbrave150 eligibility criteria. METHODS: In this multicenter study, patients with unresectable HCC treated with atezolizumab plus bevacizumab between October 2020 and May 2021 were screened. In patients who did not meet IMbrave150 eligibility criteria, treatment responses and safety at 6 and 12 weeks were evaluated. RESULTS: Atezolizumab plus bevacizumab was initiated in 64 patients, including 46 patients (71.9%) who did not meet IMbrave150 eligibility criteria. Most of these patients had a history of systemic therapy (44/46). The objective response rate and disease control rate observed using Response Evaluation Criteria in Solid Tumors 1.1 were 5.2% and 82.8% at 6 weeks and 10.0% and 84.0% at 12 weeks, respectively; these rates were similar between patients who met and did not meet the IMbrave150 criteria. Ten patients experienced progressive disease (PD) at 6 weeks. Portal vein tumor thrombosis was significantly associated with PD (p = 0.039); none of the 15 patients with hepatitis B virus-related HCC experienced PD (p = 0.050). The most common adverse events of grade 3 or higher were aspartate aminotransferase elevation (n = 8, 13.8%) and the safety profile was similar between patients who met and did not meet the IMbrave150 criteria. CONCLUSION: Most patients treated with atezolizumab plus bevacizumab did not meet the IMbrave150 criteria; however, the combination therapy showed good safety and efficacy at the early treatment phase.

12.
Nat Commun ; 12(1): 3462, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103533

RESUMO

Seasonal drawdown of dissolved inorganic carbon (DIC) in the subtropical upper ocean makes a significant contribution to net community production (NCP) globally. Although NCP requires macronutrient supply, surface macronutrients are chronically depleted, and their supply has been unable to balance the NCP demand. Here, we report nanomolar increases in surface nitrate plus nitrite (N+N, ~20 nM) and phosphate (PO4, ~15 nM) from summer to winter in the western subtropical North Pacific. Molar ratios of upward fluxes of DIC:N+N:PO4 to the euphotic zone (< 100 m) were in near-stoichiometric balance with microbial C:N:P ratios (107~243:16~35:1). Comparison of these upward influxes with other atmospheric and marine sources demonstrated that total supply is largely driven by the other sources for C and N (93~96%), but not for P (10%), suggesting that nanomolar upward supply of P and its preferential recycling play a vital role in sustaining the NCP.


Assuntos
Ecossistema , Fosfatos/análise , Clima Tropical , Carbono/análise , Nitratos/análise , Nitritos/análise , Nitrogênio/análise , Oceano Pacífico , Salinidade , Estações do Ano , Temperatura , Água/química
13.
PLoS One ; 16(3): e0247728, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33647018

RESUMO

A deteriorated liver functional reserve during systemic therapy for unresectable hepatocellular carcinoma (HCC) causes poor patient outcomes. We aimed to identify predictive factors associated with the deterioration of Child-Pugh score at 8 weeks after lenvatinib initiation. Patients with adequate clinical data and baseline preserved serum samples available were included. Baseline fibroblast growth factor (FGF)19 and 21, angiopoietin (ANG)2, and vascular endothelial growth factor (VEGF) levels were evaluated. Thirty-seven patients were included, and 6, 15, 14, and 2 experienced complete response, partial response, stable disease, and progressive disease, respectively. Twenty-four (65%) and 13 (35%) patients showed a maintained/improved and deteriorated Child-Pugh-score, respectively. While baseline clinical data, treatment response, and laboratory data were similar between these two patient groups, baseline ANG2 and VEGF levels were significantly higher (P = 0.0017) and lower (P = 0.0231), respectively, in patients with deteriorated Child-Pugh score than in those without. Based on receiver operating characteristic curve analysis, cut-off values for ANG2 and VEGF were found to be 3,108 pg/mL and 514.9 pg/mL, respectively. Among patients with low VEGF and high ANG2, 89% (8/9) exhibited a deteriorated Child-Pugh score, whereas none of the patients (0/9) with high VEGF and low ANG2 did. The deterioration of the Child-Pugh score in patients with unresectable HCC who are treated with lenvatinib may be predictable based on combined baseline serum ANG2 and VEGF levels.


Assuntos
Antineoplásicos/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Quinolinas/uso terapêutico , Fator A de Crescimento do Endotélio Vascular/genética , Proteínas de Transporte Vesicular/genética , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular , Feminino , Fatores de Crescimento de Fibroblastos/sangue , Fatores de Crescimento de Fibroblastos/genética , Expressão Gênica , Humanos , Japão , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/sangue , Proteínas de Transporte Vesicular/sangue
14.
Drug Discov Ther ; 15(1): 39-41, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33612572

RESUMO

An outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which began in Wuhan, China in December 2019, has rapidly spread all over the world. The World Health Organization characterized the disease caused by SARS-CoV-2 (COVID-19) as a pandemic in March 2020. In the absence of specific treatments for the virus, treatment options are being examined. Drug repurposing is a process of identifying new therapeutic uses for approved drugs. It is an effective strategy to discover drug molecules with new therapeutic indications. This strategy is time-saving, low-cost, and has a minimal risk of failure. Several existing approved drugs such as chloroquine, hydroxychloroquine, doxycycline, azithromycin, and ivermectin are currently in use because of their efficacy in inhibiting COVID-19. Multidrug therapy, such as a combination of hydroxychloroquine and azithromycin, a combination of doxycycline and ivermectin, or a combination of ivermectin, doxycycline, and azithromycin, has been successfully administered. Multidrug therapy is efficacious because the mechanisms of action of these drugs differ. Moreover, multidrug therapy may prevent the emergence of drug-resistant SARS-CoV-2.


Assuntos
Tratamento Farmacológico da COVID-19 , Quimioterapia Combinada/métodos , Azitromicina/uso terapêutico , Doxiciclina/uso terapêutico , Reposicionamento de Medicamentos , Humanos , Hidroxicloroquina/uso terapêutico , Ivermectina/uso terapêutico , Resultado do Tratamento
15.
Biosci Trends ; 14(6): 467-468, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33390423

RESUMO

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that struck in late 2019 and early 2020 is a serious threat to human health. Since there are no approved drugs that satisfactorily treat this condition, all efforts at drug design and/or clinical trials are warranted and reasonable. Drug repurposing is a well-known strategy that seeks to deploy existing licensed drugs for newer indications and that provides the quickest possible transition from the bench to the bedside to meet therapeutic needs. At present, several existing licensed drugs such as chloroquine, hydroxychloroquine, methylprednisolone, dexamethasone, and remdesivir have been used because of their potential efficacy in inhibiting COVID-19. Recently, antibiotics such as tetracyclines and macrolides have been reported to be effective against COVID-19. A combination of tetracyclines and macrolides may be a potential treatment for COVID-19 because there are some differences in the mechanism of action of tetracyclines and macrolides.


Assuntos
Antibacterianos/uso terapêutico , Tratamento Farmacológico da COVID-19 , Macrolídeos/uso terapêutico , Tetraciclina/uso terapêutico , Quimioterapia Combinada , Humanos
16.
J Gastroenterol ; 56(2): 168-180, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33211179

RESUMO

BACKGROUND: Entecavir and tenofovir-disoproxil-fumarate are first-line nucleos(t)ide analogs (NA) for treatment of hepatitis B virus (HBV) infections; however, their long-term administration can impact extrahepatic organs. Herein, we sought to examine the effect of NA on lipid metabolism while also characterizing the associated mechanism. METHODS: A retrospective study was performed on HBV patients administered entecavir or tenofovir-disoproxil-fumarate. Patient clinical information, as well as their preserved serum samples obtained at baseline and 6-12 months after treatment initiation, were analyzed. A 1:1 propensity score matching was applied to the assignment of tenofovir-disoproxil-fumarate or entecavir treatment. Changes in serum cholesterol, including oxidized-LDL, were analyzed. Subsequently, in vitro analysis elucidated the mechanism associated with the effect of NAs on lipid metabolism. RESULTS: Administration of tenofovir-disoproxil-fumarate, not entecavir, to chronic HBV patients, decreased serum cholesterol levels, including non-HDL and oxidized-LDL, which are strongly associated with arteriosclerosis. In vitro analysis revealed that tenofovir-disoproxil-fumarate reduced supernatant cholesterol, and upregulated the scavenger receptor, CD36, in hepatocytes. Meanwhile, silencing of hepatic CD36 increased supernatant cholesterol and negated the cholesterol-reducing effect of tenofovir-disoproxil-fumarate in HepG2-cells. Reporter, microarray, and RT-PCR analyses further revealed that tenofovir-disoproxil-fumarate treatment activates PPAR-α-mediated signaling, and upregulates PPAR-α target genes, including CPT1 and CD36. Alternatively, silencing of PPAR-α reversed the effects of tenofovir-disoproxil-fumarate on CD36. CONCLUSIONS: Tenofovir-disoproxil-fumarate modulates lipid metabolism by upregulating hepatic CD36 via PPAR-α activation. Since dyslipidemia could be associated with arteriosclerosis and hepatocarcinogenesis, these discoveries provide novel insights into anti-HBV therapies, as well as the associated extrahepatic effects of NA.


Assuntos
Hepatite B/tratamento farmacológico , Metabolismo dos Lipídeos/efeitos dos fármacos , PPAR alfa/efeitos dos fármacos , Tenofovir/farmacologia , Idoso , Antivirais/farmacologia , Antivirais/uso terapêutico , Feminino , Hepatite B/fisiopatologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tenofovir/uso terapêutico
17.
Front Bioeng Biotechnol ; 8: 602721, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363132

RESUMO

Significantly high eicosapentaenoic acid (EPA) and fucoxanthin contents with high production rate were achieved in semi continuous culture of marine diatom. Effects of dilution rate on the production of biomass and high value biocompounds such as EPA and fucoxanthin were evaluated in semi-continuous cultures of Chaetoceros gracilis under high light condition. Cellular dry weight increased at lower dilution rate and higher light intensity conditions, and cell size strongly affected EPA and fucoxanthin contents. The smaller microalgae cells showed significantly higher (p < 0.05) value of 17.1 mg g-dw-1 fucoxanthin and 41.5% EPA content per total fatty acid compared to those observed in the larger cells. Chaetoceros gracilis can accumulate relatively higher EPA and fucoxanthin than those reported previously. In addition, maintenance of small cell size by supplying sufficient nutrients and light energy can be the key for the increase production of valuable biocompounds in C. gracilis.

18.
J Biotechnol ; 323: 113-120, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32768414

RESUMO

We isolated fifty-two strains from the marine aquaculture ponds in Malaysia that were evaluated for their lipid production and ammonium tolerance and four isolates were selected as new ammonium tolerant microalgae with high-lipid production: TRG10-p102 Oocystis heteromucosa (Chlorophyceae); TRG10-p103 and TRG10-p105 Thalassiosira weissflogii (Bacillariophyceae); and TRG10-p201 Amphora coffeiformis (Bacillariophyceae). Eicosapentenoic acid (EPA) in three diatom strain was between 2.6 and 18.6 % of total fatty acids, which were higher than in O. heteromucosa. Only A. coffeiformi possessed arachidonic acid. Oocystis heteromucosa naturally grew at high ammonium concentrations (1.4-10 mM), whereas the growth of the other strains, T. weissflogii and A. coffeiformi, were visibly inhibited at high ammonium concentrations (>1.4 mM-NH4). However, two strains of T. weissflogii were able to grow at up to 10 mM-NH4 by gradually acclimating to higher ammonium concentrations. The ammonium tolerant strains, especially T. weissflogii which have high EPA contents, were identified as a valuable candidate for biomass production utilizing NH4-N media, such as ammonium-rich wastewater.


Assuntos
Compostos de Amônio/metabolismo , Aquicultura/métodos , Bioprospecção/métodos , Microalgas/metabolismo , Lagoas/microbiologia , Águas Residuárias/microbiologia , Compostos de Amônio/efeitos adversos , Biodegradação Ambiental , Biocombustíveis/microbiologia , Biomassa , Técnicas de Cultura de Células/métodos , Diatomáceas/metabolismo , Ácidos Graxos/análise , Lipídeos/biossíntese , Malásia , Microalgas/efeitos dos fármacos , Microalgas/crescimento & desenvolvimento , Poluentes Químicos da Água , Purificação da Água
19.
Hepatol Res ; 50(8): 966-977, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32562334

RESUMO

AIM: This study aimed to determine the efficacy and safety of lenvatinib for patients with unresectable hepatocellular carcinoma (HCC) who did not meet REFLECT eligibility criteria (phase 3 clinical trial). METHODS: In this multicenter retrospective study, patients with unresectable HCC treated with lenvatinib between 2018 and 2019 and had adequate clinical data were included. Objective response rate, progression-free-survival (PFS) and safety were evaluated according to meeting or not meeting the REFLECT eligibility criteria and according to the criteria of the REFLECT trial. RESULTS: Of the 105 patients included, 61% (64 of 105) did not meet the REFLECT eligibility criteria. Safety and median PFS of lenvatinib were similar between the patients who did and those who did not meet the criteria. Among the patients who did not meet the criteria, 28, 27, 14, six, seven and five had a history of tyrosine kinase inhibitor (TKI) treatment, Child-Pugh score B, HCC in ≥50% of the liver, reduced platelet count, bile duct invasion and main portal vein invasion, respectively. The efficacy and safety of lenvatinib for patients with or without Child-Pugh-score B or HCC in ≥50% of the liver were similar. Although treatment outcome was not significantly different, patients with TKI treatment history tended to have longer median PFS, whereas those with main portal vein invasion tended to have shorter median PFS. CONCLUSION: Lenvatinib was effective for patients who did not meet the REFLECT inclusion criteria. However, the treatment outcome may vary according to several factors, such as a history of TKI treatment and tumor invasion.

20.
Commun Biol ; 3(1): 172, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286494

RESUMO

Nitrogen fixing plankton provide nitrogen to fuel marine ecosystems and biogeochemical cycles but the factors that constrain their growth and habitat remain poorly understood. Here we investigate the importance of metabolic specialization in unicellular diazotroph populations, using laboratory experiments and model simulations. In clonal cultures of Crocosphaera watsonii and Cyanothece sp. spiked with 15N2, cellular 15N enrichment developed a bimodal distribution within colonies, indicating that N2 fixation was confined to a subpopulation. In a model of population metabolism, heterogeneous nitrogen (N2) fixation rates substantially reduce the respiration rate required to protect nitrogenase from O2. The energy savings from metabolic specialization is highest at slow growth rates, allowing populations to survive in deeper waters where light is low but nutrients are high. Our results suggest that heterogeneous N2 fixation in colonies of unicellular diazotrophs confers an energetic advantage that expands the ecological niche and may have facilitated the evolution of multicellular diazotrophs.


Assuntos
Evolução Biológica , Cianobactérias/metabolismo , Cyanothece/metabolismo , Metabolismo Energético , Fixação de Nitrogênio , Nitrogênio/metabolismo , Adaptação Fisiológica , Simulação por Computador , Cianobactérias/crescimento & desenvolvimento , Cyanothece/crescimento & desenvolvimento , Ecossistema , Modelos Biológicos
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