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1.
Aging (Albany NY) ; 132021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33592580

RESUMO

Macrophages are among the most abundant cells of the tumor microenvironment in head and neck squamous cancer (HNSC). Although the marker gene sets of macrophages have been found, the mechanism by which they affect macrophages and whether they further predict the clinical outcome is unclear. In this study, a univariate COX analysis and a random forest algorithm were used to construct a prognostic model. Differential expression of the key gene, methylation status, function, and signaling pathways were further analyzed. We cross-analyzed multiple databases to detect the relationship between the most critical gene and the infiltration of multiple immune cells, as well as its impact on the prognosis of pan-cancer. FANCE is recognized as hub gene by different algorithms. It was overexpressed in HNSC, and high expression was predictive of better prognosis. It might promote apoptosis through the Wnt/ß-catenin pathway. The expression of FANCE is inversely proportional to the infiltration of CD4 + T cells and their subsets, tumor-associated macrophages (TAMs), M2 macrophages, but positively co-expressed with M1 macrophages. In summary, FANCE was identified as the hub gene from the macrophage marker gene set, and it may improve the prognosis of HNSC patients by inhibiting lymphocytes and tumor-associated macrophages infiltration.

2.
Sci Total Environ ; 773: 145537, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33582331

RESUMO

Virus-laden droplets dispersion may induce transmissions of respiratory infectious diseases. Existing research mainly focuses on indoor droplet dispersion, but the mechanism of its dispersion and exposure in outdoor environment is unclear. By conducting CFD simulations, this paper investigates the evaporation and transport of solid-liquid droplets in an open outdoor environment. Droplet initial sizes (dp = 10 µm, 50 µm, 100 µm), background relative humidity (RH = 35%, 95%), background wind speed (Uref = 3 m/s, 0.2 m/s) and social distances between two people (D = 0.5 m, 1 m, 1.5 m, 3 m, 5 m) are investigated. Results show that thermal body plume is destroyed when the background wind speed is 3 m/s (Froude number Fr ~ 10). The inhalation fraction (IF) of susceptible person decreases exponentially when the social distance (D) increases from 0.5 m to 5 m. The exponential decay rate of inhalation fraction (b) ranges between 0.93 and 1.06 (IF=IF0e-b(D-0.5)) determined by the droplet initial diameter and relative humidity. Under weak background wind (Uref = 0.2 m/s, Fr ~ 0.01), the upward thermal body plume significantly influences droplet dispersion, which is similar with that in indoor space. Droplets in the initial sizes of 10 µm and 50 µm disperse upwards while most of 100 µm droplets fall down to the ground due to larger gravity force. Interestingly, the deposition fraction on susceptible person is ten times higher at Uref = 3 m/s than that at Uref = 0.2 m/s. Thus, a high outdoor wind speed does not necessarily lead to a smaller exposure risk if the susceptible person locating at the downwind region of the infected person, and people in outdoors are suggested to not only keep distance of greater than 1.5 m from each other but also stand with considerable angles from the prevailing wind direction.

3.
Future Med Chem ; 13(5): 505-528, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33438471

RESUMO

Casein kinase 1 (CK1) is an extensively expressed serine/threonine kinase family, with six highly conserved isoforms of human CK1. Due to its involvement in many biological processes, CK1 is a promising target for several pathological states, including circadian sleep disorder, neurodegenerative diseases, cancer and inflammation. However, due to the structural similarities between the six CK1 members, the design of CK1 inhibitors is intricate. So far, no effective CK1 inhibitors are reported to reach clinical trials; thus, approaches to obtaining both selective and effective CK1 inhibitors are in great demand. Here we analyze several CK1 inhibitors that provide successful experience for structure-based drug design and rational structure modification, which could provide references for further drug design.

4.
J Cutan Pathol ; 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33469928

RESUMO

Castleman disease (CD) is an unusual lymphoproliferative disorder characterized by multiple lymphadenopathy accompanied by marked systemic inflammatory symptoms. CD can be unicentric (UCD) or multicentric (MCD), and it can be classified into three types based on histopathology: hyaline vascular type, plasma cell type and mixed hyaline vascular and plasma cell type. CD involving skin is an unusual clinical manifestation. Abnormalities including rash, hyperpigmentation, cherry hemangiomatosis, paraneoplastic pemphigus, and Kaposi sarcoma have been reported to occur in MCD. Here, we reported an unusual case of MCD which presented initially with disseminated dark brown papules, patches and plaques, and pathologically demonstrated plasma cell type CD, a finding which is rarely reported. The peculiar clinicopathological features will be discussed. This article is protected by copyright. All rights reserved.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33420830

RESUMO

OBJECTIVES: To study the characteristics and the factors influencing the occurrence of the Hand-Arm Vibration Syndrome (HAVS) for a population grinding handheld workpieces in a subtropical environment. METHODS: A total of 803 workers grinding handheld workpieces formed the exposure group and 464 workers not exposed to hand-transmitted vibration (HTV) were recruited as the non-exposed group within the same factory in a subtropical climate area. The basic personal information and clinical symptoms reported were collected by trained physicians using a questionnaire and representative measurements were made of the HTV exposure levels and dose. RESULTS: The average HTV exposure dose A(8) was measured as 5.3 ± 2.0 m/s2. The proportion of grinders reporting finger blanching was 15.4% while it was 27.5% for finger numbness. Among the non-exposed group, that proportion was 0% and 6.3% respectively. There was a positive association between the vibration exposure duration and the occurrence of finger blanching, finger numbness and finger coldness. Riding a motorcycle to work was also identified as a factor that could contribute to a higher prevalence of finger blanching among the exposed workers, the OR value was found to be 1.75 (1.12, 2.75). CONCLUSIONS: Workers exposed to vibration in a subtropical area can also present evidence of finger blanching in addition to neurological symptoms. The reported rate of HAVS was positively associated with the exposure duration. And the levels of the duration of exposure relative to symptoms of vibration white finger in a subtropical temperate environment exposed to a high-frequency vibration might be deemphasized by the current ISO weighting. Motorcycle transportation to work was identified as a factor that could influence the development of the HAVS among the exposed population of grinders.

6.
Int J Med Sci ; 18(3): 736-743, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33437208

RESUMO

Background: Coronavirus disease 2019 (COVID-19) has resulted in more than 610,000 deaths worldwide since December 2019. Given the rapid deterioration of patients' condition before death, markers with efficient prognostic values are urgently required. During the treatment process, notable changes in plasma potassium levels have been observed among severely ill patients. We aimed to evaluate the association between average plasma potassium (Ka +) levels during hospitalization and 30-day mortality in patients with COVID-19. Methods: Consecutive patients with COVID-19 hospitalized in the Zhongfaxincheng branch of Tongji Hospital in Wuhan, China from February 8 to 28, 2020 were enrolled in this study. We followed patients up to 30 days after admission. Results: A total of 136 patients were included in the study. The average age was 62.1±14.6 years and 51.5% of patients were male. The median baseline potassium level was 4.3 (3.9-4.6) mmol/L and Ka + level during hospitalization was 4.4 (4.2-4.7) mmol/L; the median number of times that we measured potassium was 4 (3-5). The 30-day mortality was 19.1%. A J-shaped association was observed between Ka + and 30-day mortality. Multivariate Cox regression showed that compared with the reference group (Ka + 4.0 to <4.5 mmol/L), 30-day mortality was 1.99 (95% confidence interval [CI]=0.54-7.35, P=0.300), 1.14 (95% CI=0.39-3.32, P=0.810), and 4.14 (95% CI=1.29-13.29, P=0.017) times higher in patients with COVID-19 who had Ka + <4.0, 4.5 to <5.0, and ≥5.0 mmol/L, respectively. Conclusion: Patients with COVID-19 who had a Ka + level ≥5.0 mmol/L had a significantly increased 30-day mortality compared with those who had a Ka + level 4.0 to <4.5 mmol/L. Plasma potassium levels should be monitored routinely and maintained within appropriate ranges in patients with COVID-19.


Assuntos
/mortalidade , Mortalidade Hospitalar , Potássio/sangue , Idoso , Biomarcadores/sangue , /diagnóstico , China/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Medição de Risco/métodos , Fatores de Risco , Índice de Gravidade de Doença
7.
J Nanosci Nanotechnol ; 21(2): 995-1000, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33183435

RESUMO

Oral squamous cell carcinoma has the characteristics of high malignancy, strong invasiveness and special anatomical location. The prognosis of patients is generally poor. Invasion and metastasis of oral squamous cell carcinoma is a complex process involving multiple levels and factors. In order to explore the value of sentinel lymph node biopsy tracked by nano-carbon suspension in the treatment of early oral squamous cell carcinoma, 58 patients with early oral squamous cell carcinoma were selected in this paper. The pathological results of sentinel lymph nodes were analyzed after operation. In this study, the detection rate, sensitivity, accuracy, and false negative rate of the sentinel lymph nodes with the nano-carbon suspension were 95.6%, 86.4%, 92.2%, and 11.4%, respectively. The results show that sentinel lymph node biopsy traced by nano-carbon suspension has certain application value in guiding the treatment of early oral squamous cell carcinoma.

8.
Sci Total Environ ; 760: 144141, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341630

RESUMO

Thermal history can influence human thermal comfort through physiological (short-term) and psychological (long-term) aspects. However, the nature of the interaction between long-term and short-term thermal history is unclear. To investigate the interactive effects of long-term and short-term thermal history on outdoor thermal comfort, we conducted summer thermal comfort surveys in Melbourne (n = 3293, January-February 2014), Guangzhou, and Zhuhai (n = 4304, September 2018). The mean thermal sensation of residents of Guangzhou was higher than that of Melbourne and Zhuhai residents under a similar Universal Thermal Climate Index (UTCI) range. The preferred UTCI was the highest for Melbourne residents (19.62 °C). When UTCI was 25.6-38.4 °C, respondents' mean thermal sensation from Köppen climate zones A, B, and C was significantly higher in Guangzhou than those of Zhuhai and Melbourne. A three-way ANOVA test revealed that peoples' thermal sensations depended on a significant interaction among UTCI thermal stress levels, climate zones, and prior exposure environment. The prior exposure environment could affect the difference in thermal perception between climate zones. However, there was no significant interaction between climate zones and activity engaged in before taking the survey on thermal sensation. The difference in the thermal perception of various climate zones diminished under universally uncomfortable conditions for specific prior exposure environments and activities. The socio-ecological system model, environmental perception theory, climatocultural adaptation, and alliesthesia are useful for understanding the interactive effect of long- and short-term thermal history on outdoor thermal comfort. By revealing how people adapt to different climatic environments, our results can help ensure that people with diverse climatic backgrounds can experience thermal comfort outdoors.


Assuntos
Aclimatação , Sensação Térmica , Ecossistema , Humanos , Estações do Ano , Inquéritos e Questionários
9.
Sci Total Environ ; : 142920, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33172638

RESUMO

Urban tree planting has the potential to reduce urban heat island intensity and building energy consumption. However, the heterogeneity of cities makes it difficult to quantitatively assess the integrated impacts of tree planting and street layouts. Scaled outdoor experiments were conducted to investigate the influence of tree plantings on wind and thermal environments in two-dimensional (2D) north-south oriented street canyons with various aspect ratios (building height/street width, AR = H/W = 1, 2, 3; H = 1.2 m). The effects of tree species with similar leaf area index (C. kotoense, big crown; C. macrocarpa, small crown), tree planting densities (ρ = 1, 0.5), and arrangements (double-row, single-row) were considered. Vegetation reduces pedestrian-level wind speed by 29%-70%. For ρ = 1 and single-row arrangement, C. kotoense (big crown) has a better shading effect and decreases wall and air temperature during the daytime by up to 9.4 °C and 1.2 °C, respectively. In contrast, C. macrocarpa (small crown) leads to a temperature increase at the pedestrian level. Moreover, C. kotoense raises the air and wall temperature of the upper urban canopy layer and increases the street albedo during the daytime because of the solar radiation reflected by trees. C. kotoense/C. macrocarpa produces the maximum daytime cooling/warming and nighttime warming of air temperature when H/W = 2 owing to its weaker convective heat transfer. When H/W = 3, the building shade dominates the shading cooling and tree cooling is less significant. When ρ = 1, double-row trees (C. kotoense) reduce wall and air temperatures by up to 10.0 °C and 1.0 °C during the daytime. However, reducing ρ from 1 to 0.5 weakens the capacity of daytime cooling by C. kotoense and the warming effect by C. macrocarpa. Our study quantifies the influence of tree planting and aspect ratios on the thermal environment, which can provide meaningful references for urban tree planting and produce high-quality validation data for numerical modeling.

10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(5): 818-824, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33140605

RESUMO

At present, there are few in vivo experimental studies on anterior chamber flow field, and the relevant technologies are not mature. This study explores the experimental method and key techniques of particle image velocimetry (PIV) for the in vivo measurement of anterior chamber flow field with slow flow velocity in the rabbit with acute intraocular hypertension. The experimental process can be divided into three parts: model construction of rabbit eye with acute intraocular hypertension, in vivo eyeball preparation, and PIV setup. The following key techniques were mainly investigated: the optimal injection strategy of fluorescent particles and the correction strategy for image acquisition errors caused by the effects of image refraction and respiration. The results showed that the best injection method was that 15 µL of fluorescent particles solution was slowly injected into the anterior chamber through the lower part of iris and then the rabbit was released and waited for 13 h. In this way particles were completely distributed in the anterior chamber with the help of the aqueous humor circulation, and then in vivo PIV experiment could be performed. The eyeball should be covered with a square flume filled with ultrasonic coupling gel for the sake of imaging during the experiment. The Maximal Information Coefficient algorithm could be applied to correct the measured results before post-processing calculation. The results indicated that feasible injection strategy of fluorescent particles and the correction strategy for image acquisition are critical to obtain nice experiment effects for the in vivo PIV measurement of anterior chamber flow field in the rabbit with acute intraocular hypertension.

11.
Ecotoxicol Environ Saf ; 208: 111424, 2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33120262

RESUMO

Emerging evidences having suggested that particular lncRNAs have a potential effect on PD progression through provoking damage and inflammatory responses of microglia/ dopaminergic cells. In addition, paraquat can be accumulated in human body through various approaches and have an increased risk for Parkinson's disease. However, the specific role and mechanism of lncRNA related to neurotoxic in the progression of PD is unclear. In our study, a mouse PD model was established induced by the intraperitoneal injection of paraquat (5 mg/kg and 10 mg/kg) every three days (10 times). We determined differential expression of lncRNA AK039862 and its potential targeted genes Pafah1b1/Foxa1 in PD mouse model, then we used fluorescence in situ hybridization (FISH) to visualize the cellular distribution of AK039862. Short interfering RNAs (siRNAs) and overexpression plasmids were designed for knockdown or overexpression of AK039862. To simulate the coexisting dopaminergic cells and microglia cells in vitro, we applied several non-contact co-culture models, including conditioned medium and Transwell co-culture systems. Cytotoxicity of PQ was evaluated using bv2 cells with the concentrations: 30, 60 µM, and mn9d cells with the concentrations: 50, 100 µM. As a result, we depicted multiple interesting individual and interactive features of inflammatory lncRNA AK039862 involved in PQ-induced cellular functional effects. First, we detected that AK039862 contributed to the neuronal injury process in PQ-treated mice and co-localization of AK039862 with dopaminergic cells in vivo. And interestingly, we demonstrated that PQ significantly inhibited microglia and dopaminergic cells proliferation and microglia migration in vitro. Further research indicated that the PQ-induced low expression of AK039862 rescued microglia proliferation and migration inhibition via the AK039862/Pafah1b1/Foxa1 pathway. Meanwhile, AK039862 also participated in the interaction between microglia and dopaminergic cells with PQ treatment in non-contact co-culture models. In summary, we found that PQ inhibited the proliferation and migration of microglial cells, and elucidated AK039862 played a key role in PQ-induced neuroinflammatory damage through Pafah1b1/Foxa1. Finally, inflammatory AK039862 is involved in the complex communication between microglia and dopaminergic cells in the environment of PQ damage.

12.
Medicine (Baltimore) ; 99(41): e22671, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031333

RESUMO

Epithelial-myoepithelial carcinoma (EMC) is a rare neoplasm of the salivary glands. The aim of this study is to review and evaluate clinicopathological features and treatment of EMC of salivary gland for better sensitivity and specificity of the diagnosis.The clinical and pathological data of the 10 salivary gland EMC cases from 2008 to 2017 were analyzed.Six cases of EMC were diagnosed to be originated from parotid gland and 4 cases were from the minor salivary gland including palate, tongue, and oropharynx. Seven cases were performed radical surgery and 3 cases had radiotherapy postoperation, 2 cases had a local recurrence. The follow-up period was 4 to 104 months and the survival rate was 100%. Histopathology showed the tumors had a dominant prototypical biphasic tubular structure consisting of inner, cuboidal ductal cells and an outer layer of clear, myoepithelial cells, which grew infiltratively. The immunohistochemistry (IHC) showed the marker proteins CK, S-100, CD117, and Calponin were strongly positive in most EMC.EMC is a rare and low-grade malignant tumor with good overall survival but relatively high tendency for local recurrence. Surgery is the priority choice for EMC therapy. Complete surgical excision and negative margins are necessary for good prognosis. Imaging techniques should be used to assess the neck dissection and it is unclear whether adjuvant radiotherapy is beneficial. To ensure the sensitivity and specificity of the EMC diagnosis, we should perform both pathological and IHC analysis.


Assuntos
Carcinoma/patologia , Mioepitelioma/patologia , Neoplasias das Glândulas Salivares/patologia , Glândulas Salivares/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mioepitelioma/terapia , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/terapia
13.
ACS Chem Neurosci ; 11(19): 2978-2988, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-32898417

RESUMO

This study aimed to investigate whether the proinflammatory and pressor effects of endogenous angiotensin II (AngII) are mediated by binding to the AngII type 1 receptor (AT1R) and subsequently activating central Toll-like receptor 4 (TLR4) in the rostral ventrolateral medulla (RVLM) of stress-induced hypertensive rats (SIHR). The stress-induced hypertension (SIH) model was established by random electric foot shocks combined with noise stimulation. Mean arterial pressure, heart rate, plasma norepinephrine, and RVLM AngII and TLR4 increased in a time-dependent manner in SIHR. Pro-inflammatory cytokines (tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß)), myeloid differentiation factor 88 (MyD88), and nuclear factor (NF)-κB also increased, while anti-inflammatory cytokine IL-10 decreased in the RVLM of SIHR. These changes were attenuated by 14-day intracerebroventricular (ICV) infusion of VIPER (a TLR4 inhibitor) or candesartan (an AT1R antagonist). Both TLR4 and AT1R were expressed in the neurons and microglia in the RVLM of SIHR. Candesartan attenuated the expression of TLR4 in the RVLM of SIHR. This study demonstrated that endogenous AngII may activate AT1R to upregulate TLR4/MyD88/NF-κB signaling and subsequently trigger an inflammatory response in the RVLM of SIHR, which in turn enhanced sympathetic activity and increased blood pressure.

14.
J Int Med Res ; 48(9): 300060520936880, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32993417

RESUMO

OBJECTIVE: Increasing evidence suggests that circular RNAs (circRNAs) play a major role in tumorigenesis and cancer progression. This study aimed to identify aberrant expression of hsa_circ_0003829 in oral squamous cell carcinoma (OSCC) and to explore its clinical significance. METHODS: We conducted a prospective clinical study to examine the expression pattern of hsa_circ_0003829 in 60 paired OSCC and normal clinical samples and in cell lines using real-time quantitative polymerase chain reaction. We also evaluated the diagnostic value of hsa_circ_0003829 in OSCC based on receiver operating characteristic (ROC) curve analysis, and examined the relationships between hsa_circ_0003829 expression and clinicopathological features in patients with OSCC. We further used bioinformatics software CircInteractome (https: //Circinteractome.nia.nih.gov/) to predict circRNA-microRNA interactions. RESULTS: Hsa_circ_0003829 was significantly downregulated in OSCC compared with adjacent normal tissues. The area under the ROC curve was 0.81. Low expression levels of hsa_circ_0003829 in OSCC tissues were negatively correlated with lymph node metastasis status and TNM stage. CONCLUSIONS: Downregulated expression of has_circ_0003829 suggests that this may be a key circRNA in OSCC, and may serve as a prospective biomarker for the diagnosis of OSCC.

15.
Nucleic Acids Res ; 48(19): 11146-11161, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32986843

RESUMO

The six-subunit origin recognition complex (ORC), a DNA replication initiator, defines the localization of the origins of replication in eukaryotes. The Orc6 subunit is the smallest and the least conserved among ORC subunits. It is required for DNA replication and essential for viability in all species. Orc6 in metazoans carries a structural homology with transcription factor TFIIB and can bind DNA on its own. Here, we report a solution structure of the full-length human Orc6 (HsOrc6) alone and in a complex with DNA. We further showed that human Orc6 is composed of three independent domains: N-terminal, middle and C-terminal (HsOrc6-N, HsOrc6-M and HsOrc6-C). We also identified a distinct DNA-binding domain of human Orc6, named as HsOrc6-DBD. The detailed analysis of the structure revealed novel amino acid clusters important for the interaction with DNA. Alterations of these amino acids abolish DNA-binding ability of Orc6 and result in reduced levels of DNA replication. We propose that Orc6 is a DNA-binding subunit of human/metazoan ORC and may play roles in targeting, positioning and assembling the functional ORC at the origins.


Assuntos
Replicação do DNA , DNA/metabolismo , Complexo de Reconhecimento de Origem/metabolismo , Origem de Replicação , Humanos , Ligação Proteica , Domínios Proteicos
16.
Genomics ; 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32956844

RESUMO

OBJECTIVE: Oral squamous cell carcinoma (OSCC) is a common and rampant malignancy of the head and neck. However, its pathogenesis remains unclear. In this study, we have investigated the effects of circular RNA hsa_circ_009755 on proliferation, migration, invasion, and apoptosis in OSCC cells in vitro. METHOD: Eight pairs of OSCC and normal adjacent tissues were selected to detect the differential expression of circRNAs by high-throughput sequencing. circRNA hsa_circ_009755 expression was determined by quantitative real-time polymerase chain reaction in OSCC tissues and cell lines. CCK-8, wound healing, Transwell, and flow cytometry assays were used to determine OSCC cell proliferation, migration, invasion, and apoptosis, respectively. RESULT: The expression of hsa_circ_009755 was low in OSCC tissues and three OSCC cell lines. Silencing hsa_circ_009755 significantly enhanced the proliferation, migration, and invasion and suppressed the apoptosis of OSCC cells. CONCLUSION: Therefore, hsa_circ_009755 may be important in the tumorigenesis of OSCC.

17.
Sheng Wu Gong Cheng Xue Bao ; 36(8): 1568-1577, 2020 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-32924355

RESUMO

Catalase catalyzes the decomposition of H2O2 to H2O and O2, and has a wide range of industrial applications. However, most catalases used in the textile and paper industries are often subjected to high-alkaline challenges which makes it necessary to develop alkaline catalase. In this study, a catalase from Corynebacterium glutamicum was expressed in Escherichia coli, and the expression conditions were optimized. The recombinant catalase was purified by Ni-chelating affinity chromatography, and the recombinant enzyme was characterized. The optimal conditions of producing the recombinant catalase were: an IPTG concentration of 0.2 mmol/L, a culturing temperature of 25 °C and a culturing time of 11 h. The purified catalase had a specific activity of 55 266 U/mg, and it had a high activity in the pH range of 4.0 to11.5, with the highest activity at pH 11.0. When treated in pH 11.0 for 3 h, the enzyme retained 93% of its activity, indicating that the enzyme was qualified with a favorable stability under high-alkaline condition. The recombinant catalase had maximal activity at 30 °C, and showed a satisfactory thermal stability at a range of 25 °C to 50 °C. The apparent Km and Vmax values of purified catalase were 25.89 mmol/L and 185.18 mmol/(minmg), respectively. Besides, different inhibitors, such as sodium dodecyl sulfate (SDS), urea, NaN2, ß-mercaptoethanol, and EDTA had different degrees of inhibition on enzyme activity. The catalase from C. glutamicum shows high catalytic efficiency and high alkaline stability, suggesting its potential utilization in industrial production.


Assuntos
Catalase , Corynebacterium glutamicum , Regulação Enzimológica da Expressão Gênica , Catalase/genética , Catalase/isolamento & purificação , Catalase/metabolismo , Corynebacterium glutamicum/enzimologia , Ativação Enzimática , Estabilidade Enzimática , Concentração de Íons de Hidrogênio
18.
Molecules ; 25(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32932931

RESUMO

This study was the first designed to evaluate the extraction and antioxidant ability of triterpenes from Bergenia emeiensis rhizomes. The yield of triterpenes from B. emeiensis was mainly affected by the concentration of ethanol, followed by the extraction time, solvent to sample ratio, and the power of ultrasound. Thus, the response surface method was applied to investigate the interaction between the two factors and to optimize the extraction process. The optimal extraction conditions were 210 W, 75% ethanol, 40 min and 25 mL/g with a maximum yield of 229.37 ± 7.16 mg UAE/g. Moreover, the antioxidant ability of triterpenes from B. emeiensis (TBE) was evaluated by determining the scavenging capacity on free radicals and the protection on CHO cells and Caenorhabditis elegans against oxidative stress. The results showed the triterpenes could clear 2,2-Diphenyl-1-picryl-hydrazyl (DPPH) radicals well and had a strong reducing power. In addition, the survival of CHO cells was higher than that of the control group as a result of reducing the reactive oxygen species (ROS) level and promoting the activities of antioxidant enzymes. In addition, TBE could also enhance the survival of C. elegans under H2O2 conditions. Therefore, triterpenes from B. emeiensis could be developed into a beneficial potential for antioxidants.

19.
Clin J Am Soc Nephrol ; 15(11): 1549-1556, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32943396

RESUMO

BACKGROUND AND OBJECTIVES: Coronavirus disease 2019 is spreading rapidly across the world. This study aimed to assess the characteristics of kidney injury and its association with disease progression and death of patients with coronavirus disease 2019. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This is a retrospective study. Two representative cohorts were included. Cohort 1 involved severe and critical patients with coronavirus disease 2019 from Wuhan, China. Cohort 2 was all patients with coronavirus disease 2019 in Shenzhen city (Guangdong province, China). Any kidney injury was defined as the presence of any of the following: hematuria, proteinuria, in-hospital AKI, or prehospital AKI. AKI was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) creatinine criteria. The primary outcome was death at the end of follow-up. The secondary outcome was progression to critical illness during the study period. RESULTS: A total of 555 patients were enrolled; 42% of the cases (229 of 549) were detected with any kidney injury, 33% of the cases (174 of 520) were detected with proteinuria, 22% of the cases (112 of 520) were detected with hematuria, and 6% of the cases (29 of 520) were detected with AKI. Of the 29 patients with AKI, 21 cases were recognized as in-hospital AKI, and eight were recognized as prehospital AKI. Altogether, 27 (5%) patients died at the end of follow-up. The death rate was 11% (20 of 174) in patients with proteinuria, 16% (18 of 112) in patients with hematuria, and 41% (12 of 29) in the AKI settings. Multivariable Cox regression analysis showed that proteinuria (hazard ratio, 4.42; 95% confidence interval, 1.22 to 15.94), hematuria (hazard ratio, 4.71; 95% confidence interval, 1.61 to 13.81), and in-hospital AKI (hazard ratio, 6.84; 95% confidence interval, 2.42 to 19.31) were associated with death. Among the 520 patients with noncritical illness at admission, proteinuria (hazard ratio, 2.61; 95% confidence interval, 1.22 to 5.56) and hematuria (hazard ratio, 2.50; 95% confidence interval, 1.23 to 5.08) were found to be associated with progression to critical illness during the study period. CONCLUSIONS: Kidney injury is common in coronavirus disease 2019, and it is associated with poor clinical outcomes. PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2020_09_18_CJN04780420.mp3.


Assuntos
Lesão Renal Aguda/epidemiologia , Infecções por Coronavirus/complicações , Hematúria/epidemiologia , Pneumonia Viral/complicações , Proteinúria/epidemiologia , Lesão Renal Aguda/mortalidade , Lesão Renal Aguda/virologia , Adulto , Idoso , Betacoronavirus , China/epidemiologia , Estado Terminal , Progressão da Doença , Feminino , Hematúria/mortalidade , Hematúria/virologia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , Modelos de Riscos Proporcionais , Proteinúria/mortalidade , Proteinúria/virologia , Estudos Retrospectivos , Taxa de Sobrevida
20.
Toxicol Sci ; 178(1): 173-188, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32735315

RESUMO

Paraquat (PQ) is herbicide widely used in agricultural production. It is identified as an environmental toxicant that could lead to neurodegeneration damage. Parkinson's disease (PD) is a central nervous system degenerative disease that occurs in the elderly. Main risk factors for PD include genetic and environmental variables, but its specific mechanism is still not well understood. Emerging evidence suggests that long noncoding RNAs (lncRNAs) play an important role in PD. LncRNA NR_030777 has a full length of 2208 bp and is highly conserved among species. RNA profiling showed a significant alteration in lncRNA NR_030777 expression upon PQ-induced neurotoxicity. However, little is known on the functional relevance of lncRNA NR_030777 in the development of PQ. In this study, we discovered a vital protective role of lncRNA NR_030777 in PQ-induced neurotoxicity. The expression of NR_030777 correlates with elevated level of reactive oxygen species induced by PQ. In addition, activated expression of NR_030777 alleviates neurotoxicity by regulating the expression of Zfp326 and Copine 5. We report that lncRNA NR_030777 has a vital protective role in neurotoxicity induced by environmental toxicants such as PQ. This study could serve as an exemplary case for lncRNAs to be considered as a potential target for the prevention and treatment of PQ-induced neurodegenerative disorders such as PD.

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