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1.
Proc Natl Acad Sci U S A ; 120(13): e2213480120, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36952380

RESUMO

Peroxidase-like catalysts are safe and low-cost candidates to tackle the dilemma in constructing sustainable cathodic heterogeneous electro-Fenton (CHEF) catalysts for water purification, but the elusive structure-property relationship of enzyme-like catalysts constitutes a pressing challenge for the advancement of CHEF processes in practically relevant water and wastewater treatment. Herein, we probe the origins of catalytic efficiency in the CHEF process by artificially tailoring the peroxidase-like activity of Fe3O4 through a series of acetylated chitosan-based hydrogels, which serve as ecofriendly alternatives to traditional carbon shells. The optimized acetylated chitosan wrapping Fe3O4 hydrogel on the cathode shows an impressive activity and stability in CHEF process, overcoming the complicated and environmentally unfavored procedures in the electro-Fenton-related processes. Structural characterizations and theoretical calculations reveal that the amide group in chitosan can modulate the intrinsic redox capacity of surficial Fe sites on Fe3O4 toward CHEF catalysis via the neutral hydrogen bond. This work provides a sustainable path and molecule-level insight for the rational design of high-efficiency CHEF catalysts and beyond.

2.
Proc Natl Acad Sci U S A ; 120(24): e2219649120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276408

RESUMO

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis.


Assuntos
Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Folistatina/genética , Folistatina/metabolismo , Padronização Corporal/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação da Expressão Gênica no Desenvolvimento
3.
Mol Biol Evol ; 41(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38243850

RESUMO

Local adaptation is critical in speciation and evolution, yet comprehensive studies on proximate and ultimate causes of local adaptation are generally scarce. Here, we integrated field ecological experiments, genome sequencing, and genetic verification to demonstrate both driving forces and molecular mechanisms governing local adaptation of body coloration in a lizard from the Qinghai-Tibet Plateau. We found dark lizards from the cold meadow population had lower spectrum reflectance but higher melanin contents than light counterparts from the warm dune population. Additionally, the colorations of both dark and light lizards facilitated the camouflage and thermoregulation in their respective microhabitat simultaneously. More importantly, by genome resequencing analysis, we detected a novel mutation in Tyrp1 that underpinned this color adaptation. The allele frequencies at the site of SNP 459# in the gene of Tyrp1 are 22.22% G/C and 77.78% C/C in dark lizards and 100% G/G in light lizards. Model-predicted structure and catalytic activity showed that this mutation increased structure flexibility and catalytic activity in enzyme TYRP1, and thereby facilitated the generation of eumelanin in dark lizards. The function of the mutation in Tyrp1 was further verified by more melanin contents and darker coloration detected in the zebrafish injected with the genotype of Tyrp1 from dark lizards. Therefore, our study demonstrates that a novel mutation of a major melanin-generating gene underpins skin color variation co-selected by camouflage and thermoregulation in a lizard. The resulting strong selection may reinforce adaptive genetic divergence and enable the persistence of adjacent populations with distinct body coloration.


Assuntos
Lagartos , Melaninas , Animais , Melaninas/genética , Lagartos/genética , Peixe-Zebra , Regulação da Temperatura Corporal/genética , Pigmentação da Pele/genética , Cor
4.
Hepatology ; 75(6): 1566-1578, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34855999

RESUMO

BACKGROUND AND AIMS: Hepatitis B vaccine has been included in the infant immunization schedule since 1991 in the United States. We aimed to assess its effectiveness against HBV infection and its impact on mortality. APPROACH AND RESULTS: The study population was participants aged 6+ years with an HBV vaccination history and an HBV serologic test from the National Health and Nutrition Examination Survey, 1999-2018. Participants aged 18+ years with linked mortality records from 1999-2014 were followed for mortality analysis. Multivariable logistic regression was used to compute vaccine effectiveness (VE) overall, by year of birth, and by age. Cox regression was used to estimate HRs for all-cause, cancer-related, and cardiovascular disease-related mortality. A total of 64,107 participants were included in the main analysis, with 29,600 (40.7%) having completed HBV vaccination (three or more doses, vaccinated). The highest vaccination uptake was found among those born after 1991, at 86.5%. Vaccinated participants had higher prevalence of vaccine-induced immunity than the unvaccinated (47.2% vs. 7.4%). Among those born after 1991, VE was found at 58% (95% CI, 18%-79%) overall and 85% for those aged ≥20 years (mean age, 22), whereas no effect was found among those born prior to 1990. HBV vaccination was associated with reduced risk of all-cause mortality (HR, 0.78; 95% CI, 0.68-0.90) and cancer-related mortality (HR, 0.76; 95% CI, 0.58-1.00) but not for cardiovascular disease-related mortality. CONCLUSIONS: In the universal infant vaccination era, the HBV vaccine has shown substantial effectiveness against HBV infection and maintained strong protection for 20 years. It was also associated with reduced risk of all-cause and cancer-related mortality.


Assuntos
Doenças Cardiovasculares , Hepatite B , Neoplasias , Adulto , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Vacinas contra Hepatite B , Humanos , Programas de Imunização , Lactente , Inquéritos Nutricionais , Estados Unidos/epidemiologia , Vacinação , Adulto Jovem
5.
Mol Cell Biochem ; 478(1): 197-214, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35771397

RESUMO

Cancer resistance to anti-tumour agents has been one of the serious challenges in different types of cancer treatment. Usually, an increase in the cell death markers can predict a higher rate of survival among patients diagnosed with cancer. By increasing the regulation of survival genes, cancer cells can display a higher resistance to therapy through the suppression of anti-tumour immunity and inhibition of cell death signalling pathways. Administration of certain adjuvants may be useful in order to increase the therapeutic efficiency of anti-cancer therapy through the stimulation of different cell death pathways. Several studies have demonstrated that metformin, an antidiabetic drug with anti-cancer properties, amplifies cell death mechanisms, especially apoptosis in a broad-spectrum of cancer cells. Stimulation of the immune system by metformin has been shown to play a key role in the induction of cell death. It seems that the induction or suppression of different cell death mechanisms has a pivotal role in either sensitization or resistance of cancer cells to therapy. This review explains the cellular and molecular mechanisms of cell death following anticancer therapy. Then, we discuss the modulatory roles of metformin on different cancer cell death pathways including apoptosis, mitotic catastrophe, senescence, autophagy, ferroptosis and pyroptosis.


Assuntos
Metformina , Neoplasias , Humanos , Metformina/farmacologia , Morte Celular , Apoptose , Neoplasias/patologia , Hipoglicemiantes/farmacologia , Autofagia
6.
Bioorg Med Chem ; 82: 117234, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36906964

RESUMO

Cancer with low survival rates is the second main cause of death among all diseases in the world and consequently, effective antineoplastic agents are urgently needed. Allosecurinine is a plant-derived indolicidine securinega alkaloid shown bioactivity. The object of this study is to investigate synthetic allosecurinine derivatives with considerable anticancer capacity against nine human cancer cell lines as well as mechanism of action. We synthesized twenty-three novel allosecurinine derivatives and evaluated their antitumor activity against nine cancer cell lines for 72 h by MTT and CCK8 assays. FCM was applied to analyze the apoptosis, mitochondrial membrane potential, DNA content, ROS production, CD11b expression. Western blot was selected to analyze the protein expression. Structure-activity relationships were established and potential anticancer lead BA-3 which induced differentiation of leukemia cells towards granulocytosis at low concentration and apoptosis at high concentration was identified. Mechanism studies showed that mitochondrial pathway mediated apoptosis within cancer cells with cell cycle blocking was induced by BA-3. In addition, western blot assays revealed that BA-3 induced expression of the proapoptotic factor Bax, p21 and reduced the levels of antiapoptotic protein such as Bcl-2, XIAP, YAP1, PARP, STAT3, p-STAT3, and c-Myc. Collectively, BA-3 was a lead compound for oncotherapy at least in part, through the STAT3 pathway. These results were an important step in further studies on allosecurinine-based antitumor agent development.


Assuntos
Alcaloides , Antineoplásicos , Compostos Heterocíclicos de Anel em Ponte , Neoplasias , Humanos , Antineoplásicos/farmacologia , Azepinas/farmacologia , Compostos Heterocíclicos de Anel em Ponte/farmacologia , Lactonas/farmacologia , Apoptose , Alcaloides/farmacologia , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Linhagem Celular Tumoral
7.
Kidney Int ; 102(1): 108-120, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35341793

RESUMO

Oxidative metabolism in mitochondria regulates cellular differentiation and gene expression through intermediary metabolites and reactive oxygen species. Its role in kidney development and pathogenesis is not completely understood. Here we inactivated ubiquinone-binding protein QPC, a subunit of mitochondrial complex III, in two types of kidney progenitor cells to investigate the role of mitochondrial electron transport in kidney homeostasis. Inactivation of QPC in sine oculis-related homeobox 2 (SIX2)-expressing cap mesenchyme progenitors, which give rise to podocytes and all nephron segments except collecting ducts, resulted in perinatal death from severe kidney dysplasia. This was characterized by decreased proliferation of SIX2 progenitors and their failure to differentiate into kidney epithelium. QPC inactivation in cap mesenchyme progenitors induced activating transcription factor 4-mediated nutritional stress responses and was associated with a reduction in kidney tricarboxylic acid cycle metabolites and amino acid levels, which negatively impacted purine and pyrimidine synthesis. In contrast, QPC inactivation in ureteric tree epithelial cells, which give rise to the kidney collecting system, did not inhibit ureteric differentiation, and resulted in the development of functional kidneys that were smaller in size. Thus, our data demonstrate that mitochondrial oxidative metabolism is critical for the formation of cap mesenchyme-derived nephron segments but dispensable for formation of the kidney collecting system. Hence, our studies reveal compartment-specific needs for metabolic reprogramming during kidney development.


Assuntos
Complexo III da Cadeia de Transporte de Elétrons , Rim , Néfrons , Organogênese , Podócitos , Aminoácidos/deficiência , Diferenciação Celular , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Humanos , Rim/embriologia , Rim/metabolismo , Mesoderma/metabolismo , Néfrons/metabolismo , Organogênese/genética , Podócitos/metabolismo , Gravidez , Ureter/embriologia
8.
Cancer Cell Int ; 22(1): 36, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35073926

RESUMO

BACKGROUND: To determine whether concurrent chemotherapy is necessary during locoregional radiotherapy (RT) after palliative chemotherapy (PCT) in patients with de novo metastatic nasopharyngeal carcinoma (mNPC). METHODS: A total of 746 patients with mNPC from 2000 to 2017 at our hospital were retrospectively reviewed. Among them, 355 patients received PCT followed by RT. Overall survival (OS) and progression-free survival (PFS), including locoregional progression-free survival (LRPFS) and distant progression-free survival (DPFS) were estimated with the Kaplan-Meier method and log-rank test. Cox proportional-hazards models, landmark analyses, propensity score matching, and subgroup analyses were used to address confounding. RESULTS: Of the patients included in our study, 192 received radiotherapy alone after PCT (PCT + RT), and 163 received concurrent chemoradiotherapy after PCT (PCT + CCRT). The prognosis of PCT + CCRT was significantly better than that of PCT + RT (5 year OS, 53.0 vs 36.2%; P = 0.004). After matching, the 5 year OS rates of the two groups were 55.7 and 39.0%, respectively (P = 0.034) and the median DPFS were 29.4 and 18.7 months, respectively (P = 0.052). Multivariate Cox regression analysis indicated that PCT + CCRT was an independent favorable prognostic factor (P = 0.009). In addition, conducting concurrent chemoradiotherapy after 4-6 cycles of PCT or conducting concurrent chemotherapy with single-agent platinum was associated with significant survival benefit in the matched cohort (5 year OS rate, 60.4 or 57.4%, respectively). The survival difference between groups remained significant when evaluating patients who survived for ≥ 1 year (P = 0.028). CONCLUSIONS: The optimal treatment strategy of mNPC is the combination of PCT followed by concurrent chemoradiotherapy. More specifically, concurrent chemoradiotherapy with single-agent platinum after 4-6 cycles of PCT is suggested.

9.
Soft Matter ; 18(43): 8251-8261, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36278324

RESUMO

Spherical nanobubbles and flat micropancakes are two typical states of gas aggregation on solid-liquid surfaces. Micropancakes, which are quasi-two-dimensional gaseous structures, are often produced accompanied by surface nanobubbles. Compared with surface nanobubbles, the intrinsic properties of micropancakes are barely understood due to the challenge of the highly efficient preparation and characterization of such structures. The hydrophobicity of the substrate and gas saturation of solvents are two crucial factors for the nucleation and stability of interfacial gas domains. Herein, we investigated the synergistic effect of the surface hydrophobicity and gas saturation on the generation of interfacial gas structures. Different surface hydrophobicities were achieved by the aging process of highly oriented pyrolytic graphite (HOPG). The results indicated that higher surface hydrophobicity and gas oversaturation could create surface nanobubbles and micropancakes with higher efficiency. Strong surface hydrophobicity could promote nanobubble nucleation and higher gas saturation would induce bigger nanobubbles. Degassed experiments could remove most of these structures and prove that they are actually gaseous domains. Finally, we draw a region diagram to describe the formation conditions of nanobubbles, micropancakes based on observations. These results would be very helpful for further understanding the formation of interfacial gas structures on the hydrophobic surface under different gas saturation.

10.
Org Biomol Chem ; 20(25): 5125-5128, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35704388

RESUMO

The direct coupling of benzoxazoles and amines was realized by visible light irradiation and CuCl catalysis. Various aminated benzoxazoles were successfully synthesized under mild conditions with air as an oxidant.


Assuntos
Aminas , Benzoxazóis , Aminação , Catálise , Oxidantes
11.
Indian J Med Res ; 156(3): 529-534, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36751749

RESUMO

Background & objectives: Recently, there has been a surge to develop new devices and techniques for the diagnosis of peripheral pulmonary lesions such as the combination of LungPoint navigation and endobronchial ultrasound with a guide sheath (EBUS-GS). The present study aimed to explore the diagnostic value of LungPoint navigation in combination with EBUS-GS and rapid on-site evaluation (ROSE) particularly for peripheral pulmonary nodules. Methods: Patients (n=108) with pulmonary nodules (10 mm ≤ nodal diameter ≤30 mm) presenting to Henan Provincial People's Hospital were detected using chest computed tomographic (CT) scanning and bronchoscopy. All patients were evaluated using LungPoint navigation, EBUS-GS and ROSE techniques to evaluate the positive rate of combined diagnosis using the three methods. Results: A total of 108 patients participated in this study and successfully underwent all the three procedures. Of these, 82 patients were accurately diagnosed, making the overall diagnostic rate of 75.9 per cent for combined LungPoint navigation, EBUS-GS, and ROSE analyses. Further subgroup analysis of the diagnostic rate of the three combined techniques were conducted based on the size of the nodules which showed a diagnostic rate of 65.3 per cent for 10 mm ≤ nodule diameter ≤20 mm and 85.7 per cent for 20 mm ≤ nodal diameter ≤30 mm. Of the 108 patients, 85 had solid nodules and 23 had ground-glass nodules; the positive rate of diagnosis of solid nodules was the highest. The patients ultimately were diagnosed with lung cancer with a positive rate of 83.5 per cent. The sensitivity, specificity and positive and negative predicted values for ROSE were 90.3, 78.3, 84.8 and 83.6 per cent, respectively. Interpretation & conclusions: The combined use of the three techniques can effectively shorten the duration of the total diagnosis period and improve the safety of diagnosis without affecting the detection rate.


Assuntos
Neoplasias Pulmonares , Avaliação Rápida no Local , Humanos , Endossonografia/métodos , Broncoscopia/métodos , Estudos Retrospectivos
12.
Echocardiography ; 39(12): 1571-1580, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36376261

RESUMO

BACKGROUND: The success of transcatheter aortic valve replacement (TAVR) in native aortic regurgitation (AR) is limited by the absence of calcified anchoring structures. We sought to evaluate transfemoral TAVR in patients with native AR using a novel aortic root imaging classification. METHODS: From March to November 2021, 81 patients with severe AR were prospectively enrolled in 2 cardiac centers in China. All were evaluated using multidetector computed tomography (MDCT) and classified into 4 anatomic types in reference to transcatheter heart valve (THV) anchoring: Type 1: anchoring at the left ventricular outflow tract (LVOT), annulus, and ascending aorta (AA); Type 2: anchoring at the annulus and AA; Type 3: anchoring at the annulus and LVOT; and Type 4: anchoring at only 1 level or none at all. Based on the dual-anchoring strategy, patients with Types 1-3 were considered TAVR candidates. Procedural and 30-day outcomes were assessed according to Valve Academic Research Consortium-3 definitions. RESULTS: TAVR was performed in 32 (39.5%) patients (71.9 ± 8.0 years of age, 71.9% were male) using 2 self-expanding THVs. Types 1, 2, and 3 comprised 13 (40.6%), 11 (34.4%), and 8 (25.0%) cases, respectively. The procedural and device success rates were 100% and 93.8%, respectively, with 2 THV migration. Eight patients (25.0%) required a permanent pacemaker, and 2 (6.3%) developed moderate paravalvular leaks. No deaths or other major complications occurred during the study. CONCLUSIONS: The novel anatomic classification and dual-anchoring strategy were associated with a high procedural success rate with favorable short-term safety and clinical outcomes.


Assuntos
Insuficiência da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Humanos , Masculino , Idoso , Feminino , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , China
13.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144665

RESUMO

Selective-adsorption separation is an energy-efficient technology for the capture of acetylene (C2H2) from carbon dioxide (CO2) and ethylene (C2H4). However, it remains a critical challenge to effectively recognize C2H2 among CO2 and C2H4, owing to their analogous molecule sizes and physical properties. Herein, we report a new microporous metal-organic framework (NUM-14) possessing a carefully tailored pore system containing moderate pore size and nitro-functionalized channel surface for efficient separation of C2H2 from CO2 and C2H4. The activated NUM-14 (namely NUM-14a) exhibits sufficient pore space to acquire excellent C2H2 loading capacity (4.44 mmol g-1) under ambient conditions. In addition, it possesses dense nitro groups, acting as hydrogen bond acceptors, to selectively identify C2H2 molecules rather than CO2 and C2H4. The breakthrough experiments demonstrate the good actual separation ability of NUM-14a for C2H2/CO2 and C2H2/C2H4 mixtures. Furthermore, Grand Canonical Monte Carlo simulations indicate that the pore surface of the NUM-14a has a stronger affinity to preferentially bind C2H2 over CO2 and C2H4 via stronger C-H···O hydrogen bond interactions. This article provides some insights into customizing pore systems with desirable pore sizes and modifying groups in terms of MOF materials toward the capture of C2H2 from CO2 and C2H4 to promote the development of more MOF materials with excellent properties for gas adsorption and separation.

14.
Kidney Int ; 99(3): 657-670, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33159962

RESUMO

Abnormal mitochondrial function is a well-recognized feature of acute and chronic kidney diseases. To gain insight into the role of mitochondria in kidney homeostasis and pathogenesis, we targeted mitochondrial transcription factor A (TFAM), a protein required for mitochondrial DNA replication and transcription that plays a critical part in the maintenance of mitochondrial mass and function. To examine the consequences of disrupted mitochondrial function in kidney epithelial cells, we inactivated TFAM in sine oculis-related homeobox 2-expressing kidney progenitor cells. TFAM deficiency resulted in significantly decreased mitochondrial gene expression, mitochondrial depletion, inhibition of nephron maturation and the development of severe postnatal cystic disease, which resulted in premature death. This was associated with abnormal mitochondrial morphology, a reduction in oxygen consumption and increased glycolytic flux. Furthermore, we found that TFAM expression was reduced in murine and human polycystic kidneys, which was accompanied by mitochondrial depletion. Thus, our data suggest that dysregulation of TFAM expression and mitochondrial depletion are molecular features of kidney cystic disease that may contribute to its pathogenesis.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Animais , Proteínas de Grupo de Alta Mobilidade , Humanos , Rim , Camundongos , Proteínas Mitocondriais/genética , Fatores de Transcrição/genética
15.
J Hepatol ; 74(6): 1295-1302, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33347952

RESUMO

BACKGROUND & AIMS: The evolution and clinical significance of abnormal liver chemistries and the impact of hepatitis B infection on outcome in patients with COVID-19 is not well characterized. This study aimed to explore these issues. METHODS: This large retrospective cohort study included 2,073 patients with coronavirus disease 2019 (COVID-19) and definite outcomes in Wuhan, China. Longitudinal liver function tests were conducted, with associated factors and risk of death determined by multivariate regression analyses. A prognostic nomogram was formulated to predict the survival of patients with COVID-19. The characteristics of liver abnormalities and outcomes of patients with COVID-19, with and without hepatitis B, were compared after 1:3 propensity score matching. RESULTS: Of the 2,073 patients, 1,282 (61.8%) had abnormal liver chemistries during hospitalization, and 297 (14.3%) had a liver injury. The mean levels of aspartate aminotransferase (AST) and direct bilirubin (D-Bil) increased early after symptom onset in deceased patients and showed disparity compared to levels in discharged patients throughout the clinical course of the disease. Abnormal AST (adjusted hazard ratio [HR] 1.39; 95% CI 1.04-1.86, p = 0.027) and D-Bil (adjusted HR 1.66; 95% CI 1.22-2.26; p = 0.001) levels at admission were independent risk factors for mortality due to COVID-19. A nomogram was established based on the results of multivariate analysis and showed sufficient discriminatory power and good consistency between the prediction and the observation. HBV infection in patients did not increase the risk of poor COVID-19-associated outcomes. CONCLUSIONS: Abnormal AST and D-Bil levels at admission were independent predictors of COVID-19-related mortality. Therefore, monitoring liver chemistries, especially AST and D-Bil levels, is necessary in hospitalized patients with COVID-19. LAY SUMMARY: Liver test abnormalities (in particular elevations in the levels of aspartate aminotransferase [AST] and direct bilirubin [D-Bil]) were observed after symptom onset in patients who went on to die of coronavirus disease 2019 (COVID-19). Abnormal levels of AST and D-Bil at admission were independent predictors of COVID-19-related mortality. HBV infection in patients did not increase the risk of poor COVID-19-associated outcomes.


Assuntos
Aspartato Aminotransferases/sangue , Bilirrubina/sangue , COVID-19/mortalidade , Mortalidade Hospitalar , Hepatopatias/complicações , SARS-CoV-2 , Idoso , Feminino , Hepatite B/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Retrospectivos
16.
J Org Chem ; 86(5): 3952-3959, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577735

RESUMO

In order to prepare bridging chiral p-tert-butylcalix[4]crown-5 with a mononitro bridge substituent in a 1,3-alternate conformation, a mononitration method of calix[4]arene bridging methylene has been first developed with tert-butyl nitrite as a nitration reagent. The effects of solvent, reaction temperature, reaction time, and nitration reagent dosage on bridge mononitration have been deeply explored to obtain an optimal nitration condition. The facile nitration presents a new key for calix[4]arene bridge derivatization. After further modification and diastereoisomeric resolution, a pair of bridging chiral p-tert-butylcalix[4]arenes with a monoamino bridge substituent were produced from the bridge-mono-nitrated calix[4]arene. Their preliminary catalysis results in the Henry reaction show good catalytic activities (up to 95% yield) and still low but obviously enhanced enantioselectivities (up to 22.3% ee from 7a, 6% ee from 1), which confirms that the structural transformation indeed improves asymmetric catalysis performances of bridging chiral calix[4]crown-5 amines in a 1,3-alternate conformation.

17.
Helicobacter ; 26(2): e12786, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33596339

RESUMO

BACKGROUND: Pathogens capable of impacting gastrointestinal tract tumor development are located in the oral cavity, but whether these oral bacteria are able to colonize the gastric mucosa in gastric cancer (GC) patients and whether Helicobacter pylori infection can influence this process remains to be established. METHODS: Microbial 16S rDNA deep sequencing was conducted to characterize bacteria present in paired gastric mucosa and tongue coating samples in 27 patients with superficial gastritis (SG) and 11 GC patients. RESULTS: While the overall composition of the gastric mucosa and tongue coating microbiomes differed substantially, certain bacteria were present in both of these communities. The co-occurrence of bacteria between the tongue coating and gastric mucosa differed significantly between SG and GC patients. Of the 15 most abundant shared oral bacteria genera (the core shared oral bacteria), which were associated with differences in microbiota composition between these tongue coating and gastric mucosa, three were enriched in the gastric mucosa of GC patients relative to SG patients, whereas, 12 were depleted in GC patient samples. Furthermore, the prevalence and relative abundance of these core shared oral bacteria in the gastric mucosa were also linked to H. pylori infection status, and the core shared oral bacteria were also associated with the overall composition of the gastric mucosal microbiome. CONCLUSIONS: Helicobacter pylori infections are linked to the co-occurrence of bacteria in the oral microbiome and the gastric mucosal microbiome. Ectopic colonization of oral microbes may be a primary driver of H. pylori-induced gastric microbial dysbiosis in patients with GC.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Mucosa Gástrica , Helicobacter pylori/genética , Humanos , Boca , RNA Ribossômico 16S
18.
Dig Dis Sci ; 66(5): 1673-1682, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32591968

RESUMO

BACKGROUND: How gastric cancer (GC) incidence is associated with changes in the gastric microbiome has not been firmly established. The present study therefore aims to investigate the microbial communities present within the gastric mucosa of patients with superficial gastritis (SG) or GC. METHODS: Paired tumor and paracancerous samples of the gastric mucosa were collected from 18 patients being surgically treated for GC and from 32 patients with SG being treated via gastroscopy. The gastric microbiome in these samples was then profiled via 16S rRNA sequencing, with a linear discriminant analysis effect size (LEfSe) approach used to identify and compare different bacteria, and with PICRUSt used for predictive functional analyses. RESULTS: GC patients exhibited a distinct gastric microbiota profile from that observed in SG patients. These changes were evident in both tumor and paracancerous tissues from GC patients. Specifically, we found that 6 bacterial genera were specifically enriched in GC tissue samples relative to SG samples, while 18 genera were depleted in these same samples. Based on the differential abundance of these bacteria, we were able to calculate microbial dysbiosis index (MDI) values, which were significantly higher in GC patients than in SG patients. In addition, MDI values were negatively correlated with gastric Shannon index and were positively correlated with relative Helicobacter spp. abundance. Importantly, these MDI values were readily able to discriminate between GC and SG patient samples. Functional analysis suggested that GC patients were more likely to harbor a nitrosating microbial community. CONCLUSIONS: GC patients exhibited a gastric microbiome profile distinct from that observed in SG patients, with these differences being evident in both tumor and paracancerous tissues. Differences in the relative abundance of Helicobacter spp. may be the primary driver of gastric dysbiosis in GC patients.


Assuntos
Bactérias/isolamento & purificação , Mucosa Gástrica/microbiologia , Gastrite/microbiologia , Microbioma Gastrointestinal , Lesões Pré-Cancerosas/microbiologia , Neoplasias Gástricas/microbiologia , Idoso , Bactérias/genética , Biópsia , Disbiose , Feminino , Gastrectomia , Mucosa Gástrica/patologia , Mucosa Gástrica/cirurgia , Gastrite/patologia , Gastrite/cirurgia , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/cirurgia , Ribotipagem , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia
19.
Int J Med Sci ; 18(11): 2366-2371, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33967613

RESUMO

Coronavirus Disease 2019 (COVID-19) emerges as a global pandemic and there is a lack of evidence about the clinical course and outcome of patients on maintenance hemodialysis (MHD). Here we conducted a retrospective longitudinal study aimed to analyze the clinical features and outcome of MHD patients hospitalized with COVID-19. Of 3126 inpatients with COVID-19 at 3 Branches of Wuhan Tongji Hospital from Jan 18th to Mar 9th, 2020, 19 patients were undergoing maintenance hemodialysis. Among the 19 MHD patients with COVID-19, 6 patients (31.6%) died, and 13 patients (68.4%) were able to be discharged. Baseline characteristics, clinical courses, laboratory findings, and dynamic trajectories of major laboratory markers were compared between survivors and nonsurvivors. According to our findings, MHD patients with COVID-19 who experienced non-surviving outcome had more elevated CRP, IL6 and procalcitonin as well as fibrinogen levels at various points compared to survivors. Thus the dysregulation of immune response as well as coagulation abnormalities might be highly involved in the pathological process of COVID-19, contributing to the poor prognosis in MHD patients.


Assuntos
COVID-19/etiologia , Falência Renal Crônica/complicações , Diálise Renal , SARS-CoV-2 , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19/imunologia , Feminino , Hospitalização , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tratamento Farmacológico da COVID-19
20.
Exp Mol Pathol ; 115: 104450, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32417393

RESUMO

Nephrolithiasis is one of the most common and highly recurrent diseases worldwide. Accumulating evidence revealed the elevated miR-155 levels both in serum and urine of nephrolithiasis patients. The aim of our research was to explore the role of miR-155 in CaOx-induced apoptosis in HK-2 cells. The expression levels of miR-155 in serum and renal tissues were quantified in 20 patients with nephrolithiasis using qRT-PCR assay. ELISA was performed to determine urinary levels of interleukin (IL)-1ß, IL-6 and tumor necrosis factor-alpha (TNF-α). Renal tubular cell model of CaOx nephrolithiasis was established to investigate the role and molelular mechanism of miR-155. Cell viability and apoptosis were assessed by MTT and flow cytometry, respectively. Immunofluoresent staining of LC3 autophagosome and western blotting were performed to evaluate the autophagic activity. Luciferase reporter assay was employed to verify the interaction between miR-155 and PI3KCA/Rheb. PI3K/Akt/mTOR signaling was further examined by western blotting. Serum and renal levels of miR-155 and inflammatory factors were significantly elevated in nephrolithiasis patients than in controls. CaOx treatment caused up-regulation of miR-155 and induced autophagy in renal tubular epithelial cells, while silencing miR-155 or inhibition of autophagy by 3-metheladenine (3-MA) ameliorated CaOx crystal-induced cell injury. PI3KCA and Rheb was identified as downstream targets of miR-155. Moreover, miR-155 activates autophagy and promotes cell injury through repressing PI3K/Akt/mTOR signaling pathway. Taken together, these findings demonstrated that miR-155 facilitates CaOx crystal-induced renal tubular epithelial cell injury via PI3K/Akt/mTOR-mediated autophagy, providing therapeutic targets for ameliorating cellular damage by CaOx crystals.


Assuntos
Autofagia/efeitos dos fármacos , Oxalato de Cálcio/toxicidade , MicroRNAs/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sequência de Bases , Estudos de Casos e Controles , Linhagem Celular , Cristalização , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/sangue , Rim/patologia , Masculino , MicroRNAs/sangue , MicroRNAs/genética , Pessoa de Meia-Idade , Nefrolitíase/sangue , Nefrolitíase/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Regulação para Cima/efeitos dos fármacos
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