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1.
Glob Chang Biol ; 30(1): e17114, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273577

RESUMEN

Human activity and climate change affect biodiversity and cause species range shifts, contractions, and expansions. Globally, human activities and climate change have emerged as persistent threats to biodiversity, leading to approximately 68% of the ~522 primate species being threatened with extinction. Here, we used habitat suitability models and integrated data on human population density, gross domestic product (GDP), road construction, the normalized difference vegetation index (NDVI), the location of protected areas (PAs), and climate change to predict potential changes in the distributional range and richness of 26 China's primate species. Our results indicate that both PAs and NDVI have a positive impact on primate distributions. With increasing anthropogenic pressure, species' ranges were restricted to areas of high vegetation cover and in PAs surrounded by buffer zones of 2.7-4.5 km and a core area of PAs at least 0.1-0.5 km from the closest edge of the PA. Areas with a GDP below the Chinese national average of 100,000 yuan were found to be ecologically vulnerable, and this had a negative impact on primate distributions. Changes in temperature and precipitation were also significant contributors to a reduction in the range of primate species. Under the expected influence of climate change over the next 30-50 years, we found that highly suitable habitat for primates will continue to decrease and species will be restricted to smaller and more peripheral parts of their current range. Areas of high primate diversity are expected to lose from 3 to 7 species. We recommend that immediate action be taken, including expanding China's National Park Program, the Ecological Conservation Redline Program, and the Natural Forest Protection Program, along with a stronger national policy promoting alternative/sustainable livelihoods for people in the local communities adjacent to primate ranges, to offset the detrimental effects of anthropogenic activities and climate change on primate survivorship.


Asunto(s)
Cambio Climático , Conservación de los Recursos Naturales , Animales , Humanos , Primates , Biodiversidad , Ecosistema , Actividades Humanas , China
2.
Arch Microbiol ; 204(1): 53, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34936048

RESUMEN

A Gram-positive strain APA H-16(1)T was isolated from a saline-alkali soil sample collected from Heilongjiang Province, China. Cells were rod shaped, non-motile, endospore forming, and aerobic. Growth occurred at 10-45 °C (optimum, 35 °C), pH 7.0-10.5 (optimum, pH 9.5), and could tolerate NaCl up to 15.0% (w/v). Strain showed low 16S rRNA gene sequence similarities with Alteribacter natronophilus (97.8%), Alteribacter aurantiacus (97.7%), and Alteribacter populi (97.1%). The cell wall peptidoglycan was meso-diaminopimelic acid. The predominant menaquinone was MK-7. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified aminophospholipids, unidentified phospholipid, and unidentified lipid. The major fatty acids were anteiso-C15:0, and iso-C15:0. The genomic G + C content was 45.1%. The average nucleotide identity and digital DNA-DNA hybridization values between strain APA H-16(1)T and the most closely related species were below the cut-off level (95-96%; 70%) for species delineation. Based on phenotypic, phylogenetic, chemotaxonomic, and genome comparison, strain APA H-16(1)T represents a novel species of the genus Alteribacter, for which the name Alteribacter salitolerans sp. nov. is proposed. The type strain is APA H-16(1)T (= KCTC 43228T = CICC 25092T).


Asunto(s)
Microbiología del Suelo , Suelo , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
3.
Phys Chem Chem Phys ; 14(2): 835-9, 2012 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-22120498

RESUMEN

The second order polarizabilities (ß) of the C(3)N(4) NT systems were investigated in this study. The ß values of end groups substituted C(3)N(4) NTs were calculated to find their most favorable paradigm for nonlinear optical design. It was found that their electric dipole transitions are only allowed along the tube axis direction and the position of terminal groups has a great effect on NLO properties of substituted C(3)N(4) NTs. The obtained results provide us details to understand the relation between the structure and nonlinear optical properties. The results indicate that the second-order polarizabilities originate from charge transfer from a donor (-NH(2)) to an acceptor (-O(2)N) and the electron density redistribution in heptazine units. We employ a one-dimensional two-state model to analyze the nature of the second-order polarizabilities of studied materials. The frequency-dependent second-order polarizabilities were also calculated. The second-order polarizability of the O(2)N-C(3)N(4)-NH(2) NT is 2.51 × 10(-27) esu when the input photon energy is 2.232 eV, which is much larger (about two orders of magnitude) than static second-order polarizability (2.54 × 10(-29)).

4.
Front Med (Lausanne) ; 9: 988830, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36330063

RESUMEN

Background: Pulmonary carcinosarcoma (PCS) is a rare but aggressive malignant disease in the lung. It is characterized by coexisting histologic elements of carcinomatous and sarcomatous components. This study aimed to comprehensively understand the clinical features of PCS and develop a nomogram for prognostic prediction of PCS patients. Methods: Data were collected from the Surveillance Epidemiology and End Results (SEER) database between 1975 and 2018. Propensity-score matching (PSM) was used to match the demographic characteristic of the PCS vs. pulmonary sarcoma (PS). Cancer-specific survival (CSS) and overall survival (OS) were the main endpoints of the survival of patients and were evaluated using the Kaplan Meier curves and Cox proportional hazards regression. We further randomly split enrolled PCS patients from SEER into the training and validation sets. All independent predictors for OS of the training set were integrated to create a predictive nomogram. The performance of the nomogram was determined by discrimination, calibration ability, clinical usefulness, and risk stratification ability both in the training and validation cohorts. In addition, the clinical data of PCS patients from the West China Hospital were also retrospectively analyzed by this model. Results: A total of 428 PCS patients and 249 PS patients were enrolled from SEER. Compared to pure PS, PCS was associated with significantly better survival in the unmatched cohorts, whereas non-significantly better survival after PSM. In subgroup analysis, PCS showed significantly worse survival than pure PS in subgroups among the race, marital status, and radiation treatment. A nomogram was constructed for PCS patients' survival prediction by combining the independent risk factors, including gender, stage, surgery, radiation, and chemotherapy. The nomogram showed good discrimination, calibration, and predictive power in the training and validation sets. Risk stratification analysis indicated that the nomogram scores efficiently divided PCS patients into low and high-risk groups. Conclusion: PCS is a rare malignant disease of the lung with distinct clinical features. It had a comparable survival compared with pure PS in the matched cohorts. In addition, a nomogram was developed and validated for predicting the OS in PCS patients.

5.
Curr Oncol ; 29(1): 267-282, 2022 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-35049699

RESUMEN

PURPOSE: Immune-related pneumonitis (IRP) has attracted extensive attention, owing to its increased mortality rate. Conventional chemotherapy (C) has been considered as an immunosuppressive agent and may thus reduce IRP's risk when used in combination with PD-1/L1 inhibitors. This study aimed to assess the risk of IRP with PD-1/L1 inhibitors plus chemotherapy (I+C) versus PD-1/L1 inhibitors alone (I) in solid cancer treatment. METHOD: Multiple databases were searched for RCTs before January 2021. This NMA was performed among I+C, I, and C to investigate IRP's risk. Subgroup analysis was carried out on the basis of different PD-1/L1 inhibitors and cancer types. RESULTS: Thirty-one RCTs (19,624 patients) were included. The I+C group exhibited a lower risk of IRP in any grade (RR, 0.60; 95% CI, 0.38-0.95) and in grade 3-5 (RR, 0.44; 95% CI, 0.21-0.92) as opposed to the I group. The risk of any grade IRP with PD-1 plus chemotherapy was lower than that with PD-1 monotherapy (RR, 0.50; 95% CI, 0.28-0.89), although grade 3-5 IRP was similar. There was no statistically meaningful difference in the risk of any grade IRP between PD-L1 plus chemotherapy and PD-L1 inhibitors monotherapy (RR, 0.95; 95% CI, 0.43-2.09) or grade 3-5 IRP (RR, 0.71;95% CI, 0.24-2.07). In addition, compared with the I group, the I+C group was correlated with a decreased risk in IRP regardless of cancer type, while a substantial difference was only observed in NSCLC patients for grade 3-5 IRP (RR, 0.39; 95% CI, 0.15-0.98). CONCLUSION: In comparison to PD-1/L1 inhibitor treatment alone, combining chemotherapy with PD-1/L1 inhibitors might reduce the risk of IRP in the general population. Furthermore, PD-1 inhibitors in combination with chemotherapy were correlated with a decreased risk of IRP compared to PD-1 inhibitor treatment alone. In contrast to the I group, the I+C group exhibited a lower risk of IRP, especially for NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neumonía , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Humanos , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares/tratamiento farmacológico , Metaanálisis en Red , Neumonía/tratamiento farmacológico , Receptor de Muerte Celular Programada 1 , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
World J Gastrointest Oncol ; 12(7): 705-718, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32864039

RESUMEN

In 2017 the World Health Organization revised the criteria for classification of pancreatic neuroendocrine neoplasms (pNENs) after a consensus conference at the International Agency for Research on Cancer. The major change in the new classification was to subclassify the original G3 group into well-differentiated pancreatic neuroendocrine tumors G3 (pNETs G3) and poorly differentiated pancreatic neuroendocrine carcinomas (pNECs), which have been gradually proven to be completely different in biological behavior and clinical manifestations in recent years. In 2019 this major change subsequently extended to NENs involving the entire digestive tract. The updated version of the pNENs grading system marks a growing awareness of these heterogeneous tumors. This review discusses the clinicopathological, genetic and therapeutic features of poorly differentiated pNECs and compare them to those of well-differentiated pNETs G3. For pNETs G3 and pNECs (due to their lower incidence), there are still many problems to be investigated. Previous studies under the new grading classification also need to be reinterpreted. This review summarizes the relevant literature from the perspective of the differences between pNETs G3 and pNECs in order to deepen understanding of these diseases and discuss future research directions.

7.
Medicine (Baltimore) ; 99(36): e21980, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32899039

RESUMEN

For the diagnosis of gastric adenosquamous carcinoma (ASC), discrepancies regarding a rational diagnostic proportion of the squamous cell carcinoma (SCC) component exist among different organizations. Our study aimed to evaluate the impact of the SCC component on the survival of gastric cancer patients and identify the optimal cutoff value for the SCC component necessary for diagnosing gastric ASC.Cases of gastric cancer with an SCC component were obtained from our center and from case reports and series extracted from Medline. Univariate and multivariate analyses were conducted to compare the overall survival between groups and examine the prognostic value of various clinical parameters.We identified 45 qualified cases in published literature and 13 in our center. Forty-two of them were males and 16 females (M: F = 2.6:1). Thirty of them were Asian patients and the rest were mainly from the United States and Europe. The mean age was 61.1 years (median 64 years, range 32-84 years). The average tumor size was 6.9 cm (median 6.0 cm, range 2.0-16.0 cm). The most common location of the cancer was the lower third (39.7%). Although a statistical difference was not achieved, the Kaplan-Meier curve demonstrated that as the proportion of the SCC component in the primary lesion increased, the patients' survival risk increased (P = .489), and the presence of the SCC component in metastatic lymph nodes also increased the risk of survival (P = .259); both of these findings indicated a negative impact of the SCC component on survival. Furthermore, we identified the optimal cutoff for the SCC component as 35% (χ = 6.544, P = .011), which was subsequently validated in a Cox regression model as an independent prognostic factor (P = .026).An increased proportion of the SCC component is associated with worse survival in gastric cancer patients with an SCC component. The optimal cutoff for the proportion of the SCC component necessary for the diagnosis of gastric ASC is 35%.


Asunto(s)
Carcinoma Adenoescamoso/mortalidad , Carcinoma de Células Escamosas/mortalidad , Neoplasias Gástricas/mortalidad , Estómago/patología , Carcinoma Adenoescamoso/patología , Carcinoma de Células Escamosas/patología , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Neoplasias Gástricas/patología
8.
Front Oncol ; 10: 548867, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33194604

RESUMEN

Human epidermal growth factor receptor 2 (HER2) has been verified as a valuable biomarker and treatment target in metastatic colorectal cancer (mCRC). Pyrotinib, a novel irreversible HER2/epidermal growth factor receptor (EGFR) dual tyrosine kinase inhibitor, can efficiently inhibit the proliferation of HER2-positive cancer cells in many tumors. We report a case of a 40-year-old woman with both HER2- and EGFR-amplified metastatic colon cancer, who developed refractory disease resistant to multiline therapies (including trastuzumab with lapatinib) but achieved a remarkable response after pyrotinib treatment. For patients with HER2-positive mCRC, who have developed resistance to trastuzumab and lapatinib, pyrotinib is a promising new candidate, which can be used as salvage therapy.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 23(4): 437-9, 2006 Aug.
Artículo en Zh | MEDLINE | ID: mdl-16883535

RESUMEN

OBJECTIVE: To investigate the relationship between the HLA-DQB1 allele polymorphisms and the clinical features of 15 familial myasthenia gravis (MG) cases in north China. METHODS: By polymerase chain reaction-sequence specific primers (PCR-SSP), the HLA-DQB1 gene polymorphisms were determined in 64 MG patients (15 familial and 49 sporadic) and 52 healthy individuals as control group. The clinical characteristics of 15 familial MG patients and 49 sporadic were analyzed. The measurement data was analyzed by t test and enumeration data by chi-square test. RESULTS: The frequency of DQB1*0501 was significantly increased in familial MG, especially in the ocular type, compared with sporadic MG (P<0.05, OR=3.08) and healthy controls (P<0.01, OR=4.439). Comparing with healthy controls, the frequency of DQB1*0301/4 was increased (P<0.05, OR=2.56), while the frequency of DQB1*0601 was significantly decreased (P<0.05, OR=0.33) in sporadic MG. The familial patients had an early age of disease onset, but less severity and good prognosis. CONCLUSION: The familial MG has distinctive clinical features. DQB1*0501 allele is positively related to the genetic susceptibility to familial MG patients in north China, especially to the ocular type. DQB1*0301/4 allele is positively related to the pathogenesis of sporadic MG. DQB1*0601 may be a protecting allele for sporadic MG. The phenotype of MG may be the result of interaction of hereditary defects and environmental factors. The familial MG may be different from sporadic patients in genetic immune mechanism.


Asunto(s)
Antígenos HLA-DQ/genética , Miastenia Gravis/genética , Polimorfismo Genético/genética , Adolescente , Adulto , Anciano , Alelos , Niño , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Cadenas beta de HLA-DQ , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Adulto Joven
12.
Sci Rep ; 6: 21675, 2016 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-26899360

RESUMEN

While the worldwide standardization of agricultural production has been advocated and recommended, relatively little research has focused on the ecological significance of such a shift. The ecological concerns stemming from the standardization of agricultural production may require new methodology. In this study, we concentrated on how ecological two-sidedness and ecological processes affect the standardization of agricultural production which was divided into three phrases (pre-, mid- and post-production), considering both the positive and negative effects of agricultural processes. We constructed evaluation indicator systems for the pre-, mid- and post-production phases and here we presented a Standardization of Green Production Index (SGPI) based on the Full Permutation Polygon Synthetic Indicator (FPPSI) method which we used to assess the superiority of three methods of standardized production for peaches. The values of SGPI for pre-, mid- and post-production were 0.121 (Level IV, "Excellent" standard), 0.379 (Level III, "Good" standard), and 0.769 × 10(-2) (Level IV, "Excellent" standard), respectively. Here we aimed to explore the integrated application of ecological two-sidedness and ecological process in agricultural production. Our results are of use to decision-makers and ecologists focusing on eco-agriculture and those farmers who hope to implement standardized agricultural production practices.


Asunto(s)
Agricultura/normas , Conservación de los Recursos Naturales/estadística & datos numéricos , Modelos Estadísticos , Prunus persica/fisiología , China , Ecosistema , Humanos
13.
Clin Neurol Neurosurg ; 122: 4-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24908208

RESUMEN

BACKGROUND: Low education level has been thought an important and specific risk factor for dementia. Therefore, we surveyed dementia in a highly educated population in Tianjin, China. METHODS: In total, 1324 old people (aged 55 years and over) in three cluster samples from university communities in Tianjin responded to our survey. Data from psychological tests and dementia questionnaires were analyzed. RESULTS: The prevalence of all-cause dementia, Alzheimer's disease (AD), and vascular dementia (VD) was 4.98%, 2.11%, and 2.27%, respectively. A history of stroke (OR=6.036), lack of fruit (OR=5.489), early parental death (OR=3.102), household financial management (OR=2.638), a history of cardiovascular disease (OR=2.434), a history of hypertension (OR=2.042), physical exercise (OR=2.556), were significantly associated with dementia in a single-factor analysis. Four independent variables were entered in a regression equation: early parental death (OR=6.417), lack of fruit in the diet (OR=3.919), personal stroke history (OR=3.901), and lack of physical exercise (OR=2.220). CONCLUSION: The prevalence of dementia was lower in highly educated elderly people in universities in Tianjin than in the general population. Risk factors for dementia included disease history, living habits, and early parental death, so corresponding interventions are required.


Asunto(s)
Demencia/epidemiología , Anciano , Anciano de 80 o más Años , China/epidemiología , Escolaridad , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
14.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 21(5): 1207-10, 2013 Oct.
Artículo en Zh | MEDLINE | ID: mdl-24156435

RESUMEN

Platelet apoptosis elucidated by either physical or chemical compound or platelet storage occurs wildly, which might play important roles in controlling the numbers and functions of circulated platelets, or in the development of some platelet-related diseases. However, up to now, a little is known about the regulatory mechanisms of platelet apoptosis. Protein kinase C (PKC) is highly expressed in platelets and plays central roles in regulating platelet functions. Although there is evidence indicating that PKC is involved in the regulation of apoptosis of nucleated cells, it is still unclear whether PKC plays a role in platelet apoptosis. The aim of this study was to investigate the role of PKC in platelet apoptosis. The effects of PKC on mitochondrial membrane potential (ΔΨm), phosphatidylserine (PS) exposure, and caspase-3 activation of platelets were analyzed by flow cytometry and Western blot. The results showed that the ΔΨm depolarization in platelets was induced by PKC activator in time-dependent manner, and the caspase-3 activation in platelets was induced by PKC in concentration-dependent manner. However, the platelets incubated with PKC inhibitor did not results in ΔΨm depolarization and PS exposure. It is concluded that the PKC activation induces platelet apoptosis through influencing the mitochondrial functions and activating caspase 3. The finds suggest a novel mechanism for PKC in regulating platelet numbers and functions, which has important pathophysiological implications for thrombosis and hemostasis.


Asunto(s)
Apoptosis , Plaquetas/citología , Plaquetas/metabolismo , Proteína Quinasa C/metabolismo , Caspasa 3/metabolismo , Humanos , Potencial de la Membrana Mitocondrial , Fosfatidilserinas/metabolismo
15.
Chin Med J (Engl) ; 124(6): 901-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21518600

RESUMEN

BACKGROUND: Endothelial dysfunction is thought to be critical events in the pathogenesis of Alzheimer's disease (AD). Endothelial progenitor cells (EPCs) have provided insight into maintaining and repairing endothelial function. To study the relation between EPCs and AD, we explored the number of circulating EPCs in patients with AD. METHODS: A total of 104 patients were recruited from both the outpatients and inpatients of the geriatric neurology department at General Hospital, Tianjin Medical University. Consecutive patients with newly diagnosed AD (n = 30), patients with vascular dementia (VaD, n = 34), and healthy elderly control subjects with normal cognition (n = 40) were enrolled after matching for age, gender, body mass index, medical history, current medication and Mini Mental State Examination. Middle cerebral artery flow velocity was examined with transcranial Doppler. Endothelial function was evaluated according to the level of EPCs, and peripheral blood EPCs was counted by flow cytometry. RESULTS: There were no significant statistical differences of clinical data in AD, VaD and control groups (P > 0.05). The patients with AD showed decreased CD34-positive (CD34(+)) or CD133-positive (CD133(+)) levels compared to the control subjects, but there were no significant statistical differences in patients with AD. The patients with AD had significantly lower CD34(+)CD133(+) EPCs (CD34 and CD133 double positive endothelial progenitor cells) than the control subjects (P < 0.05). In the patients with AD, a lower CD34(+)CD133(+) EPCs count was independently associated with a lower Mini-Mental State Examination score (r = 0.514,P = 0.004). Patients with VaD also showed a significant decrease in CD34(+)CD133(+) EPCs levels, but this was not evidently associated with the Mini-Mental State Examination score. The changes of middle cerebral artery flow velocity were similar between AD and VaD. Middle cerebral artery flow velocity was decreased in the AD and VaD groups and significantly lower than the normal control group (P < 0.01). There was no significant difference of the blood flow velocity between the AD and VaD patients (P > 0.05). CONCLUSIONS: The results provided evidence that patients with AD have reduced circulating EPCs. Endothelial function is impaired in patients with AD and vascular factors have a role in the pathogenesis of AD. CD34(+)CD133(+) EPCs may be a novel biomarker of AD dementia.


Asunto(s)
Enfermedad de Alzheimer/patología , Demencia Vascular/patología , Células Endoteliales/citología , Células Endoteliales/metabolismo , Células Madre/citología , Células Madre/metabolismo , Antígeno AC133 , Anciano , Enfermedad de Alzheimer/metabolismo , Antígenos CD/metabolismo , Antígenos CD34/metabolismo , Demencia Vascular/metabolismo , Femenino , Glicoproteínas/metabolismo , Humanos , Masculino , Péptidos/metabolismo
16.
World J Gastroenterol ; 5(3): 228-230, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11819436

RESUMEN

AIM:To investigate the role of apolipoprotein E (apoE) polymorphism in the lithogenesis of gallstone and the hereditary pathogenesis of the disease.METHODS: Polymerase chain reaction (PCR) was used to study apoE phenotypes and allele frequencies in patients with gallstones and control, and the fasting serum lipids of subjects were also measured by enzymatic methods.RESULTS:The levels of triglyceride (TG) and very low density lipoprotein cholesterol (VLDL-C) were much higher in E(2/3) patients than that in E(2/3) control. E(3/3) patients were accompanied with remarkably low levels of high density lipoprotein cholesterol (HDL-C) and its subforms.But in E(3/4) patients there were only slight changes in levels of VLDL-C and low density lipoprotein cholesterol (LDL-C).CONCLUSION:Different apoE phenotype patients with gallstones have different cheracteristics of dyslipidemia and the average level of serum lipids in patients with gallstones are higher than subjects without gallstones in the same apoE gene phenotype.epsilon2 allele is possibly one of the dangerous factors in the lithogenesis of cholecystolithiasis.

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