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1.
Biotechnol Lett ; 46(2): 223-233, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38310624

RESUMEN

Bilirubin, a key active ingredient of bezoars with extensive clinical applications in China, is produced through a chemical process. However, this method suffers from inefficiency and adverse environmental impacts. To address this challenge, we present a novel and efficient approach for bilirubin production via whole-cell transformation. In this study, we employed Corynebacterium glutamicum ATCC13032 to express a ß-glucuronidase (StGUS), an enzyme from Staphylococcus sp. RLH1 that effectively hydrolyzes conjugated bilirubin to bilirubin. Following the optimization of the biotransformation conditions, a remarkable conversion rate of 79.7% in the generation of bilirubin was obtained at temperate 40 °C, pH 7.0, 1 mM Mg2+ and 6 mM antioxidant NaHSO3 after 12 h. These findings hold significant potential for establishing an industrially viable platform for large-scale bilirubin production.


Asunto(s)
Bilirrubina , Corynebacterium glutamicum , Glucuronidasa/genética , Glucuronidasa/metabolismo , Corynebacterium glutamicum/metabolismo , Staphylococcus , China
2.
J Bone Miner Metab ; 42(1): 17-26, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38062272

RESUMEN

INTRODUCTION: The bone tissue is susceptible to hypergravity (+ G) environment. It is necessary to discuss the extent to which specific + G values are beneficial or detrimental to bone tissue. The objective of this study was to characterize the effects of high + G values on mechanical properties, microstructures, and cellular metabolism of bone. MATERIALS AND METHODS: 30 male Wistar rats aged 12 weeks were randomly divided into 5 groups, and bore different + G (namely + 1G, + 4G, + 8G, + 10G and + 12G) environments respectively for 4 weeks, 5 days each week, and 3 minutes each day. The macro-mechanical parameters, microstructure parameters, and mRNA transcription levels of the tibia were determined through the three-point bending method, micro-CT detection, and q-PCR analysis, respectively. RESULTS: As the + G value increases, hypergravity becomes increasingly detrimental to the macro-mechanical performance of rat tibia. Concerning the microstructure of cancellous bone, there appears to be a favorable trend at + 4G, followed by a progressively detrimental trend at higher G values. In addition, the mRNA transcription levels of OPG and RANKL show an initial tendency of enhanced bone absorption at +4G, followed by an increase in bone remodeling capacity as G value increases. CONCLUSION: The higher G values correspond to poorer macro-mechanical properties of the tibia, and a + 4G environment benefits the microstructure of the tibia. At the cellular level, bone resorption is enhanced in the + 4G group, but the bone remodeling capability gradually increases with further increments in G values.


Asunto(s)
Hipergravedad , Tibia , Ratas , Masculino , Animales , Ratas Wistar , Remodelación Ósea , ARN Mensajero/genética , ARN Mensajero/metabolismo , Densidad Ósea
3.
Medicine (Baltimore) ; 101(44): e31238, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36343047

RESUMEN

At present, the mechanism of reciprocal ST-segment depression (RSTD) is unclear. ST-segment changes may be caused by the potential difference between the positive and negative electrodes, although this requires further investigation. The characteristics of RSTD and their relationship with ST-segment elevation in acute ST segment elevation myocardial infarction (STEMI) patients were analyzed. We replaced the negative electrode of the precordial leads of an inferior wall myocardial infarction patient and observed the changes in the ST-segment of the precordial leads. A total of 85 patients were included, of which 75 were patients with RSTD. All 45 patients with inferior myocardial infarction had limb lead RSTD, and 37 had anterior lead ST-segment depression. All ST-segment changes in STEMI can be explained by the proposed mechanism, and the value of ST segment depression in limb leads can be calculated by the value of ST segment elevation. In summary, the mechanism of RSTD in acute myocardial infarction may be that the action potential (AP) of the negative electrode of the lead weakens or disappears and the AP of the positive electrode may not be completely offset, resulting in ST-segment depression. Animal experimental studies are needed for further confirmation. When the negative electrode of the precordial lead is changed in acute inferior wall myocardial infarction patient, the ST-segment of the precordial lead changes accordingly. All the changes are consistent with our analysis.


Asunto(s)
Infarto de la Pared Anterior del Miocardio , Infarto de la Pared Inferior del Miocardio , Infarto del Miocardio , Infarto del Miocardio con Elevación del ST , Humanos , Infarto del Miocardio con Elevación del ST/diagnóstico , Depresión , Electrocardiografía , Infarto del Miocardio/diagnóstico , Arritmias Cardíacas
4.
Medicine (Baltimore) ; 101(38): e30812, 2022 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-36197171

RESUMEN

There has been an epidemic of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) delta variant in Jingmen, China, and the clinical and epidemiological characteristics of all patients infected with SARS-CoV-2 delta variant in an epidemic are rarely reported. All the coronavirus disease 2019 (COVID-19) patients diagnosed in Jingmen in August 2021 were enrolled in this study. Epidemiological data and clinical characteristics were analyzed. Of 58 patients (38 male and 20 female), 11 were children. The mean age was 35 years, and the median age was 39 years (range, 1-60 years; interquartile range, 28-51). The infectivity of the SARS-CoV-2 Delta variant may have increased, but pathogenicity could have decreased significantly. The vast majority of patients had either no symptoms or mild symptoms. Even though the variant virus is highly contagious, control measures have proven effective. Symptoms included fever (53%), cough (48%), headache (6%), runny nose (13%), loss of smell and taste (6%), elevated C-reactive protein (26%), increased neutrophil count (13%), decreased eosinophil count (21%), and elevated mononuclear granulocytes (26%). Thirty-eight of the 47 adults showed lymphocyte decline, but none of the children showed a significant decline, and more than half of them showed an increase. Thirty patients had no pneumonia, 27 patients had mild pneumonia, and only one patient with multiple chronic diseases had severe pneumonia. None of the 11 children had been vaccinated, 10 did not have pneumonia, and 1 had a small lung lesion. The number of new patients disappeared in 15 days after the lockdown of the city.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adolescente , Adulto , Proteína C-Reactiva/metabolismo , COVID-19/epidemiología , Niño , Preescolar , China/epidemiología , Control de Enfermedades Transmisibles , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
5.
Clin Cardiol ; 43(12): 1534-1538, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33022118

RESUMEN

BACKGROUND: The development of a perfect method for determining the mean QRS axis (ÂQRS) is still lacking. HYPOTHESIS: We proposed a new simple method, whether this method is accurate is unknown. METHODS: The axis perpendicular to the mean QRS axis (P-ÂQRS) divides six limb leads into two groups. All the leads that are in the range of 180° along the ÂQRS are positive, while all the leads in another 180° are negative, one lead is isodiphasic if it is on the P-ÂQRS. If no lead is isodiphasic, then the P-ÂQRS is located in the middle of two adjacent leads, which can help us determine the P-ÂQRS. The six limb leads that fall in the range of -30° to 120° are as follows: aVL (-30°), I (0°), -aVR (30°), II (60°), aVF (90°), and III (120°). We can check an external lead (aVL or III) first. For example, if lead III is isodiphasic and lead aVF is positive, the P-ÂQRS is 120°; if lead III is negative and lead aVF is positive, then the P-ÂQRS is 105°. If more than one lead is negative, all such leads can be checked individually until a positive or isodiphasic lead is found. The ÂQRS can be easily decided once we know the P-ÂQRS. In total, 200 recorded ECGs were investigated. We obtained the ÂQRS from our new method, computer interpretations, and a standard bipolar method. The Pearson correlation coefficient and Bland-Altman analysis were performed. RESULTS: The mean and SDs were remarkably similar, the correlation coefficient between the P-ÂQRS method and the bipolar method was 0.976 (P < .001). Mean bias (Bland-Altman limits of agreement) between the two methods was 0.885 (-12.37 to 14.14). CONCLUSION: The new method is simple and is able to assess the mean QRS axis accurately.


Asunto(s)
Electrocardiografía/métodos , Cardiopatías/diagnóstico , Frecuencia Cardíaca/fisiología , Cardiopatías/fisiopatología , Humanos , Reproducibilidad de los Resultados
6.
Medicine (Baltimore) ; 99(23): e20605, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32502034

RESUMEN

There is currently a global outbreak of coronavirus disease 2019 (COVID-19), and its epidemic characteristics in the areas where the outbreak has been successfully controlled are rarely reported.Describe the epidemic characteristics of COVID-19 in Jingmen, Hubei, introduce the local prevention and control experience, and observe the impact of various prevention and control measures on the number of new cases.All the COVID-19 patients diagnosed in the municipal districts of Jingmen from January 12 to February 29, 2020 were enrolled in this study. We described epidemiological data and observed the impact of control measures on the epidemic.Of the 219 cases (110 men and 109 women), 88 (40%) had exposure to Wuhan. The median age was 48 years (range, 2-88 years; IQR, 35-60). Thirty-three severe patients with a median age of 66 years (range, 33-82 years, IQR, 57-76) were treated in intensive care units; out of these patients, 66.7% (22) were men and 19 (57.5%) had chronic diseases, including hypertension, diabetes, heart failure, stroke, and renal insufficiency. Under the control measures, the number of new patients gradually decreased and nearly disappeared after 18 days. Wearing masks in all kinds of situations prevents most infections and is one of the most effective prevention and control measures.In conclusion, all people are susceptible to COVID-19, and older males and those with comorbid conditions are more likely to become severe cases. Even though COVID-19 is highly contagious, control measures have proven to be very effective, particularly wearing masks, which could prevent most infections.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Control de Infecciones/métodos , Neumonía Viral/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , COVID-19 , Niño , Preescolar , China/epidemiología , Comorbilidad , Infecciones por Coronavirus/complicaciones , Brotes de Enfermedades , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/complicaciones , Estudios Retrospectivos , Adulto Joven
7.
Chin Med J (Engl) ; 131(5): 539-543, 2018 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-29483387

RESUMEN

BACKGROUND: The sigma receptors are a relatively novel receptor group with respect to knowledge of their effect on health. Although the sigma-1 receptor agonist PRE-084 exhibits a cardioprotective effect in some studies, the benefits in cases of myocardial ischemia/reperfusion (I/R) are not clear. The aim of this study was to explore the mechanism of action and assess the effect of PRE-084 on myocardial I/R injury in rats. METHODS: In this study, rats were assigned randomly to three groups with computer (n = 14 for each group): a sham group, an I/R group, and a PRE-084 group. In the PRE-084 group, rats were administered PRE-084 1 h before operation. In the myocardial I/R model, the left anterior descending branch of rats was ligated and opened half an hour later. Cardiac function was assessed, and the apoptosis index was evaluated. The mechanisms of the cardioprotective effects of PRE-084 were explored. RESULTS: PRE-084 pretreatment preserved cardiac function and reduced myocardial apoptosis (F = 86.0, P < 0.01) with Western blotting analysis, showing significantly reduced expression of Bax (F = 75.7, P < 0.01) and cleaved-caspase 3 (F = 44.7, P < 0.01), along with increased expression of the Bcl-2 protein (P < 0.01) and phosphorylated protein kinase B (p-Akt) (P < 0.01) and phosphorylated-endothelial nitric oxide synthase (p-eNOS; P < 0.01). CONCLUSION: PRE-084 preserved cardiac function and reduced myocardial apoptosis through the activation of Akt and eNOS.


Asunto(s)
Morfolinas/uso terapéutico , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Receptores sigma/metabolismo , Animales , Western Blotting , Caspasa 3/metabolismo , Masculino , Isquemia Miocárdica/tratamiento farmacológico , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Receptor Sigma-1
8.
Medicine (Baltimore) ; 94(32): e1279, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26266362

RESUMEN

Whether adenosine offers cardioprotective effects when used as an adjunctive therapy for patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) remains controversial.To evaluate, via meta-analysis, the efficacy of adenosine in patients with AMI undergoing PCI.Randomized controlled trials (RCTs) published in Medline, Embase, and the Cochrane Central Register of Controlled Trials.RCTs of patients with AMI undergoing primary PCI, comparing adenosine treatment and placebo groups and reporting mortality, thrombolysis in myocardial infarction (TIMI) flow grade, myocardial blush grade (MBG), re-infarction, left-ventricular ejection fraction (LVEF), ST-segment elevation resolution (STR), recurrent angina, or heart failure (HF).Risk of bias was assessed by the Cochrane guidelines and publication bias by Egger's test. For studies reported in multiple publications, the most complete publication was used. Arms using different dosing schedules were merged. Mean differences (MDs) or risk ratios (RRs) were determined.Data were extracted from 15 RCTs involving 1736 patients. Compared with placebo, adenosine therapy was associated with fewer occurrences of heart failure (RR: 0.65, 95% confidence interval [CI]: 0.43-0.97, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.03) and no-reflow (TIMI flow grade <3, RR: 0.62, 95% CI: 0.45-0.85, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.003; MBG[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0-1, RR: 0.81; 95% CI: 0.67-0.98, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.03), more occurrences of STR (RR: 1.19, 95% CI: 1.07-1.31, P[REPLACEMENT CHARACTER]<[REPLACEMENT CHARACTER]0.00001), but no overall improvement of LVEF (MD: 2.29, 95% CI: -0.09 to 4.67, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.06). Adenosine improved LVEF in the intravenous subgroup and the regular-dose intracoronary (IC) subgroup (0.24-2.25[REPLACEMENT CHARACTER]mg) compared with placebo (MD: 2.68, 95% CI: 0.66-4.70, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.009). Adenosine was associated with a poorer LVEF in the high-dose (4-6[REPLACEMENT CHARACTER]mg) IC subgroup (MD: -2.40; 95% CI: -4.72 to -0.09, P[REPLACEMENT CHARACTER]=[REPLACEMENT CHARACTER]0.04). There was no significant evidence that adenosine reduced rates of all-cause mortality, cardiovascular mortality or re-infarction after PCI.Adenosine dosage and administration routes, baseline profiles, and endpoints differed among included RCTs. Performance, publication, and reporting biases remain possible.Adenosine therapy appears to improve several outcomes in patients with AMI after PCI, but there is no evidence that adenosine can reduce mortality rates.


Asunto(s)
Adenosina/uso terapéutico , Cardiotónicos/uso terapéutico , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/terapia , Vasodilatadores/uso terapéutico , Adenosina/farmacología , Humanos , Intervención Coronaria Percutánea , Volumen Sistólico/efectos de los fármacos , Vasodilatadores/farmacología
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