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1.
Water Res ; 238: 120014, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37146392

RESUMO

The oxidation of the emerging nanomaterial black phosphorus (BP) affected by pH and oxygen has been carefully documented. However, in natural waters, there is a large amount of chemically reactive organic matters like fulvic acid (FA), whose impacts on degradation and stability of few-layer BP or BP nanosheets (BPNS) are scarcely disclosed. Hence, we investigated the kinetics of BPNS degradation products (H2PO2-, HPO32-, and PO43-) in the presence of FA. The results showed that the apparent reaction rate constants of BPNS were 0.026, 0.050, and 0.060 d-1 under oxygen-and-light condition and 0.005, 0.016, and 0.023 d-1 under hypoxia-and-darkness condition at FA gradients of 0, 2.5, and 5 mgC/L, respectively. Microscopic observations, simple molecular simulation experiment, and density functional theory computation explained that FA significantly enhanced the degradation of P atoms on the BPNS surface through the indirect pathway of reducing the energy barrier of O2 dissociative adsorption and the direct pathway of chemical adsorption, which caused the P-P bond on the BPNS surface to break down and formed P-O bonds or C-P bonds. This study revealed for the first time the degradation mechanism of BPNS in the presence of FA, which is a chemical mechanism of the BPNS transformation behavior. It helps to make a more scientific risk assessment of BP in natural waters.


Assuntos
Nanoestruturas , Fósforo , Fósforo/química , Benzopiranos/química , Oxigênio
2.
Proc Natl Acad Sci U S A ; 118(5)2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33452205

RESUMO

The outbreak of COVID-19 caused by SARS-CoV-2 has resulted in more than 50 million confirmed cases and over 1 million deaths worldwide as of November 2020. Currently, there are no effective antivirals approved by the Food and Drug Administration to contain this pandemic except the antiviral agent remdesivir. In addition, the trimeric spike protein on the viral surface is highly glycosylated and almost 200,000 variants with mutations at more than 1,000 positions in its 1,273 amino acid sequence were reported, posing a major challenge in the development of antibodies and vaccines. It is therefore urgently needed to have alternative and timely treatments for the disease. In this study, we used a cell-based infection assay to screen more than 3,000 agents used in humans and animals, including 2,855 small molecules and 190 traditional herbal medicines, and identified 15 active small molecules in concentrations ranging from 0.1 nM to 50 µM. Two enzymatic assays, along with molecular modeling, were then developed to confirm those targeting the virus 3CL protease and the RNA-dependent RNA polymerase. Several water extracts of herbal medicines were active in the cell-based assay and could be further developed as plant-derived anti-SARS-CoV-2 agents. Some of the active compounds identified in the screen were further tested in vivo, and it was found that mefloquine, nelfinavir, and extracts of Ganoderma lucidum (RF3), Perilla frutescens, and Mentha haplocalyx were effective in a challenge study using hamsters as disease model.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/efeitos dos fármacos , Adulto , Animais , Antivirais/química , Antivirais/uso terapêutico , COVID-19/epidemiologia , COVID-19/virologia , Chlorocebus aethiops , Cricetinae , Modelos Animais de Doenças , Reposicionamento de Medicamentos/métodos , Feminino , Humanos , Masculino , Pandemias , Extratos Vegetais/farmacologia , SARS-CoV-2/genética , Células Vero
3.
J Ethnopharmacol ; 241: 111801, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30878546

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Rhodiola crenulata, a traditional Tibetan medicine, has shown promise in the treatment of hypobaric hypoxia (HH)-induced brain injury. However, the underlying mechanisms remain unclear. This study investigated the protective effects of R. crenulata aqueous extract (RCAE) on HH-induced brain injury in rats. MATERIALS AND METHODS: An animal model of high-altitude hypoxic brain injury was established in SD rats using an animal decompression chamber for 24 h. Serum and hippocampus levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG), and lactate dehydrogenase (LDH) were then determined using commercial biochemical kits. Neuron morphology and vitality were also evaluated using H&E and Nissl staining, and TUNEL staining was used to examine apoptosis. Gene and protein expression of HIF-1α, microRNA 210, ISCU1/2, COX10, Apaf-1, cleaved Caspase-3, Caspase-3, Bax, Bcl-2, and Cyto-c were determined by western blot, immunohistochemical and qRT-PCR analysis. RESULTS: RCAE administration attenuated HH-induced brain injury as evidenced by decreased levels of MDA, LDH, and GSSG, increased GSH and SOD, improvements in hippocampus histopathological changes, increased cell vitality and ATP level, and reduced apoptotic cell numbers. RCAE treatment also enhanced HIF-1α, ISCU1/2, COX10, and Bcl-2 protein expression, while dramatically inhibiting expression of Apaf-1, Bax, Cyto-c, and cleaved Caspase-3. Treatment also increased gene levels of HIF-1α, microRNA 210, ISCU1/2, and COX10, and decreased Caspase-3 gene production. CONCLUSIONS: RCAE attenuated HH-induced brain injury by regulating apoptosis and mitochondrial energy metabolism via the HIF-1α/microRNA 210/ISCU1/2 (COX10) signaling pathway.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Rhodiola , Animais , Apoptose/efeitos dos fármacos , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Metabolismo Energético/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipóxia/complicações , Hipóxia/tratamento farmacológico , Hipóxia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Extratos Vegetais/farmacologia , Ratos Sprague-Dawley
4.
Phytother Res ; 33(4): 1074-1083, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30768733

RESUMO

Osteoporosis is characterized by low bone mineral density and microarchitectural deterioration of bone tissue. N-(3-methoxybenzyl)-(9Z,12Z,15Z)-octadecatrienamide (MBOC) is one of the macamides isolated from Maca (Lepidium meyenii Walp.), a cruciferous plant from the Andes of Peru. In this study, C3H/10T1/2 mesenchymal stem cells were treated with MBOC in osteogenic induction medium. An ovariectomized (OVX) mouse model was used to investigate the effect of 1-month MBOC treatment on the prevention of postmenopausal osteoporosis. Remarkably, trabecular thickness, trabecular number, and bone volume/tissue volume of the distal femoral metaphysis were significantly increased in OVX + MBOC mice compared with OVX mice, as revealed by microcomputed tomography analysis. Trabecular separation was decreased in OVX + MBOC mice compared with OVX mice. Consistently, MBOC increased the levels of osteocalcin and runt-related transcription factor 2 in OVX mice, as well as the expression of runt-related transcription factor 2, osterix, and alkaline phosphatase in C3H/10T1/2 cells. Mechanistically, MBOC activates the canonical Wnt/ß-catenin signaling pathway via inhibiting phosphorylation of GSK-3ß at Tyr216 and maintaining ß-catenin expression. Collectively, the current study demonstrates the robustness of MBOC in the induction of mesenchymal stem cells osteogenic differentiation and consequent bone formation, suggesting that MBOC may be a potentially effective drug to treat postmenopausal osteoporosis.


Assuntos
Lepidium/química , Osteoporose/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Diferenciação Celular , Proliferação de Células , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Osteoporose/patologia
5.
Clin Gastroenterol Hepatol ; 17(7): 1303-1310.e18, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29654915

RESUMO

BACKGROUND & AIMS: The Chinese herbal medicine, MaZiRenWan (MZRW), has been used for more than 2000 years to treat constipation, but it has not been tested in a randomized controlled trial. We performed a trial to evaluate the efficacy and safety of MZRW, compared with the stimulant laxative senna or placebo, for patients with functional constipation (FC). METHODS: We performed a double-blind, double-dummy, trial of 291 patients with FC based on Rome III criteria, seen at 8 clinics in Hong Kong from June 2013 through August 2015. Patients were observed for 2 weeks and then assigned randomly (1:1:1) to groups given MZRW (7.5 g, twice daily), senna (15 mg daily), or placebo for 8 weeks. Patients were then followed for 8 weeks and evaluated at baseline and weeks 4, 8 (end of treatment), and 16 (end of follow up). Participants recorded information on stool form and frequency, feeling of complete evacuation, and research medication taken. Data on individual bowel symptoms, global symptom improvement, and adverse events were collected. A complete response was defined as an increase ≥1 complete spontaneous bowel movement (CSBM)/week from baseline (the primary outcome). Secondary outcomes included response during the follow-up period, colonic transit, individual and global symptom assessments, quality of life measured with 36-item short form Chinese version, and adverse events. RESULTS: Although there was no statistically significant difference in proportions of patients with a complete response to MZRW (68%) vs. senna (57.7%) (P = .14) at week 8, there was a statistically significant difference vs. placebo (33.0%) (P < .005). At the 16-week timepoint (after the 8-week follow-up period), 47.4% of patients had a complete response to MZRW, 20.6% had a complete response to senna, and 17.5% had a complete response to placebo (P < .005 for MZRW vs. placebo). The group that received MZRW group also had significant increases in colonic transit and reduced severity of constipation, straining, incomplete evacuation, and global constipation symptoms compared with the groups that received placebo or senna in (P < .05 for all comparisons). CONCLUSIONS: In a randomized controlled trial of 291 patients with FC, we found MZRW to be well-tolerated and effective in increasing CSBM/week. MZRW did not appear to be more effective than senna and might be considered as an alternative to this drug. ClincialTrials.gov no: NCT01695850.


Assuntos
Constipação Intestinal/tratamento farmacológico , Defecação/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Qualidade de Vida , Constipação Intestinal/fisiopatologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
6.
Medicine (Baltimore) ; 96(46): e8643, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29145289

RESUMO

RATIONALE: Metallic mercury poisoning through intravenous injection is rare, especially for a homicide attempt. Diagnosis and treatment of the disease are challenging. PATIENT CONCERNS: A 34-year-old male presented with pyrexia, chill, fatigue, body aches, and pain of the dorsal aspect of right foot. Another case is that of a 29-year-old male who committed suicide by injecting himself metallic mercury 15 g intravenously and presented with dizzy, dyspnea, fatigue, sweatiness, and waist soreness. DIAGNOSIS: The patient's condition in case 1 was deteriorated after initial treatment. Imaging studies revealed multiple high-density spots throughout the body especially in the lungs. On further questioning, the patient's girlfriend acknowledged that she injected him about 40 g mercury intravenously 11 days ago. The diagnosis was then confirmed with a urinary mercury concentration of 4828 mg/L. INTERVENTIONS: Surgical excision, continuous blood purification, plasma exchange, alveolar lavage, and chelation were performed successively in case 1. Blood irrigation and chelation therapy were performed in case 2. OUTCOMES: The laboratory test results and organ function of the patient in case 1 gradually returned to normal. However, in case 2, the patient's dyspnea was getting worse and he finally died due to toxic encephalopathy and respiratory failure. LESSONS: Early diagnosis and appropriate treatment are critical for intravenous mercury poisoning. It should be concerned about the combined use of chelation agents and other treatments, such as surgical excision, hemodialysis and plasma exchange in clinical settings.


Assuntos
Intoxicação por Mercúrio/diagnóstico , Intoxicação por Mercúrio/terapia , Mercúrio/administração & dosagem , Adulto , Evolução Fatal , Homicídio , Humanos , Injeções Intravenosas , Masculino , Suicídio
7.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1245-1250, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29052381

RESUMO

According to the findings, modified Ganlu Yaoyu San has a good anti-inflammatory activity, and can significantly alleviate the degree of arthritis. Its therapeutic effect for rheumatoid arthritis may be related to the regulation of MAPK pathway of synovial cells. In the study, the rat adjuvant arthritis(AA) model was established to further investigate the pharmacodynamic mechanism for regulating MAPK pathway of synovial cells. Enzyme-linked immune assay was used to determine the serum TNF-α level of AA rats administered with drug for two weeks, synovial tissue protein kinases ERK1/2 and p38 content were determined by immunohistochemistry, synovial tissue JNK1, ERK1, p38 gene(mRNA) expression were detected with fluorescence quantitative PCR(RT-PCR) method. According to the results, after administration for two weeks, the levels of serum TNF-α of AA rat was significantly decreased(P<0.05). After administration for four weeks, the protein expressions of p38 and ERK1/2 in synovial tissue were reduced(P<0.05 or P<0.01), the gene expressions of JNK1, p38 and ERK1 in knee joint synovial tissue were reduced(P<0.05 or P<0.01). In conclusion, modified Ganlu Yaoyu San can effectively treat rheumatoid arthritis. Its mechanism might be related to the reduction of TNF-α levels in serum, protein expression of p38 and ERK1/2 in synovial tissue, and JNK1, p38 and ERK1 gene expressions, and regulation of MAPK pathway.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Medicamentos de Ervas Chinesas/farmacologia , Sistema de Sinalização das MAP Quinases , Animais , Ratos , Membrana Sinovial/enzimologia , Fator de Necrose Tumoral alfa/sangue , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
8.
BMC Nephrol ; 16: 87, 2015 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-26099512

RESUMO

BACKGROUND: Inflammation is considered one of the major causes of protein-energy wasting in maintenance hemodialysis (MHD) patients. It is unclear whether dietary interventions can impact nutritional status and quality of life in MHD patients with elevated C-reactive protein (CRP) levels. Therefore, we examined the hypothesis that supervised intra-dialysis protein supplementation in MHD patients with elevated plasma CRP will improve protein stores and quality of life. METHODS: A 24 week, two phase, longitudinal, single center, open labeled study of 50 MHD patients with plasma CRP > 3 mg/L was conducted. During the 12-week observation phase dietary advice was provided to increase protein intake to 1.2 g/kg/day. In the 12-week treatment phase 45 g of liquid protein supplement was provided at each dialysis treatment. Protein nitrogen appearance (PNA), mid-arm muscle circumference (MAMC), serum albumin, body mass index (BMI) and quality of life (assessed by Short Form-12 questionnaire) were measured at baseline, 12 and 24 weeks. RESULTS: Median plasma CRP at baseline was 16.0 (IQR 7.7 to 25.1) mg/L. The mean MAMC was 26.5 ± 3.9 cm, BMI 29.2 ± 6.9 kg/m(2) and plasma albumin 3.8 ± 0.3 g/dl. During the intervention period, mean PNA increased by 0.13 g/kg/d (p = 0.01) under a mixed effects model. However, there were no clinically or statistically significant effects on MAMC (p = 0.87), plasma albumin (p = 0.70), BMI (p = 0.09), physical (p = 0.32) or mental (p = 0.96) composite scores. CONCLUSIONS: In MHD patients with elevated plasma CRP but otherwise mostly normal nutritional parameters, intra-dialytic oral protein supplement was effective in increasing protein intake but did not provide a detectable impact on nutritional status or quality of life.


Assuntos
Proteínas Alimentares/uso terapêutico , Suplementos Nutricionais , Falência Renal Crônica/terapia , Diálise Renal/métodos , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Braço , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Estudos de Coortes , Feminino , Humanos , Falência Renal Crônica/metabolismo , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Estado Nutricional , Tamanho do Órgão , Estudos Prospectivos , Qualidade de Vida , Albumina Sérica , Resultado do Tratamento
9.
Zhongguo Zhen Jiu ; 31(1): 65-7, 2011 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-21355162

RESUMO

The detailed operating methods and the clinical application of the unique acupuncture therapy established by professor XIE Qiang and applied specially in otorhinolaryngologic department are introduced, ie. acupuncture and moxibustion methods for regulating channels and contacting qi, transferring focus of excitation, needling movement and needling ying combined with minimally invasive needle scalpel. Meanwhile, the position of the experience acupoints named Kaiyin 1 (ease-up the voice 1) and Kaiyin 2 (ease-up the voice 2) and their manipulation are recommended, and the clinical application of these acupuncture methods and acupoints for inflammation and pain in otorhinolaryngologic department are explained.


Assuntos
Terapia por Acupuntura , Otorrinolaringopatias/terapia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Moxibustão , Manejo da Dor , Adulto Jovem
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