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1.
Artigo em Zh | MEDLINE | ID: mdl-37667164

RESUMO

Severe acute dichlorvos poisoning is characterized by rapid onset, swift disease progression and serious complications. It frequently involves multiple organ failure (central, respiratory and circulatory systems), severe acidosis, and rare occurrences of gastric perforation. When secondary gastric perforation occurs, treatment becomes difficult and the prognosis of patients is poor. Thus, early and sufficient gastrointestinal decontamination is crucial. This article presented two cases of gastric perforation secondary to dichlorvos poisoning and discussed the causes of gastric perforation, as well is clinical diagnostic and treatment methods.


Assuntos
Diclorvós , Insuficiência de Múltiplos Órgãos , Humanos
2.
Artigo em Zh | MEDLINE | ID: mdl-35785900

RESUMO

Chlorfenapyr is a moderately dangerous insecticide widely used in agriculture. The mortality of acute poisoning patients is high, and there is no effective treatment. This paper retrospectively analyzes the clinical data of two cases of compound chlorfenapyr poisoning. The main symptoms of the patients were high fever, sweating, gradual coma, increased creatine kinase and myoglobin, with delayed poisoning symptoms. Despite comprehensive treatment, both patients died eventually. It indicated that chlorfenapyr was highly toxic and had a high mortality. In addition to routine symptomatic treatment for patients with acute poisoning, blood purification treatment should be actively carried out in the early stage.


Assuntos
Inseticidas , Piretrinas , Agricultura , Humanos , Estudos Retrospectivos
3.
Neoplasma ; 67(3): 557-566, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32122143

RESUMO

Hepatocellular carcinoma (HCC) is one of the most famous fatal malignancies in the world. LncRNA SNHG1 has been shown to play roles in the development and progression of various tumors, including HCC. The present study aims to investigate the deeper molecular mechanisms of SNHG1 in HCC. The expression levels of SNHG1 and miR-377-3p were detected by qRT-PCR in HCC tissues and cells. MTT assay was used to examine cell proliferation. Cell apoptosis was evaluated by detecting the apoptotic rate and the protein level of C-caspase 3 using flow cytometry and western blot assays. The protein levels of EMT-related proteins (E-cadherin, N-cadherin, and Vimentin) were measured by western blot. Cell migration and invasion were examined by transwell assay. Xenograft analysis was performed to explore the tumor growth in vivo. The binding sites of SNHG1 and miR-377-3p were predicted by the online software and confirmed by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay. We found that SNHG1 was markedly upregulated in HCC tissues and cells. Knockdown of SNHG1 induced apoptosis and inhibited proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) of HCC cells. SNHG1 knockdown suppressed the tumor growth of HCC in vivo. SNHG1 directly bound to miR-377-3p. Knockdown of miR-377-3p attenuated the effect of SNHG1 knockdown on proliferation, apoptosis, migration, invasion, and EMT of HCC cells. In conclusion, SNHG1 inhibited apoptosis and induced proliferation, migration, invasion, and EMT by sponging miR-377-3p in HCC, which indicated that SNHG1 may be a potential biomarker and therapeutic target for HCC treatment.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , Carcinoma Hepatocelular/genética , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Metástase Neoplásica
4.
Zhonghua Yi Xue Za Zhi ; 99(11): 841-843, 2019 Mar 19.
Artigo em Zh | MEDLINE | ID: mdl-30893728

RESUMO

Objective: To compare the difference of preoperative planning parameters between 3D-printing non-coplanar template (3D-PNCT) and 3D-printing coplanar template (3D-PCT) in the treatment of pelvic wall recurrent gynecological malignant tumor with radioactive seeds implantation, and to guide the clinical application. Methods: From January 2016 to March 2018, 33 patients with pelvic wall recurrent gynecological malignant tumor were treated with radioactive seeds implantation assisted by 3D-printing template and in Peking University Third Hospital. All patients underwent 3D-PNCT and 3D-PCT preoperative planning. The D(90) of target remained similar for the same patient. The parameters were compared with Wilcoxon test or Kruskal-Wallis test. Results: D(90) was similar between the two groups (P>0.05). The number of inserting needles through intestine and bone in 3D-PNCT group was less than that in 3D-PCT group (0 (0-13), 0 (0-25), Z=-2.941, P<0.05;0 (0-3), 0 (0-25), Z=-2.232, P<0.05). Conclusion: For patients with gynecological malignancies with pelvic recurrence, both of the two peroperative plans could achieve prescription dose, but 3D-PNCT is more safer.


Assuntos
Impressão Tridimensional , Feminino , Neoplasias dos Genitais Femininos , Humanos , Radioisótopos do Iodo , Recidiva Local de Neoplasia , Neoplasias Pélvicas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
5.
Zhonghua Yi Xue Za Zhi ; 98(37): 3014-3016, 2018 Oct 09.
Artigo em Zh | MEDLINE | ID: mdl-30392259

RESUMO

Objective: To evaluate the relationship of dosimetry parameters and efficacy of (125)I seeds implantation for pelvic recurrent cervical cancer (PRCC) after external beam radiotherapy(EBRT) under CT guidance. Methods: A retrospective analysis was made on 30 PRCC patients after EBRT in Peking University Third Hospital with (125)I seeds implantation under CT guidance. Postoperative plans were made to evaluate the dosimetric parameters. Kaplan-Meier method was used to calculate local progression free survival (LPFS) rate and overall survival (OS) rate, and Log-rank test and Cox regression were used for univariate and multivariate analysis. Results: The 1-year and 2-year LPFS rate was 39.4% and 22.5%, respectively. The 1-year and 2-year OS rate was 57.3% and 27.4%, respectively. On postoperative plan, D(90) was (132±47) Gy, D(100) was (51±24) Gy, V(100) was 88%±10%, V(150)was 69%±15%, V(200) was 51%±18%.LPFS time would be longer while D(90) ≥105 Gy or D(100) ≥ 55 Gy or V(100) ≥ 91% (all P<0.05). D(100) was significantly related to LPFS (P<0.05). But these dosimetry parameters got no effect on OS. Conclusions: LPFS time of (125)I seeds implantation for PRCC after EBRT under CT guidance would be longer when D(90)≥105 Gy or D(100)≥ 55 Gy, or V(100)≥ 91%. D(100) is an independent factor related to LPFS.


Assuntos
Dosagem Radioterapêutica , Neoplasias do Colo do Útero , Braquiterapia , Feminino , Humanos , Isótopos de Iodo , Recidiva Local de Neoplasia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Neoplasias do Colo do Útero/radioterapia
6.
Artigo em Inglês | MEDLINE | ID: mdl-26898324

RESUMO

microRNA-210 (miR-210), the master hypoxamir, is overexpressed and generally exhibits oncogenic properties in most human solid tumours, including colorectal cancer (CRC). However, the status of circulating miR-210 in CRC is still unknown. This study aims to assess the clinical significance of circulating miR-210 in CRC. Using (reverse transcription quantitative PCR) RT-qPCR analysis, we compared the expression levels of circulating miR-210 in serum of 268 CRC patients and 102 healthy controls, and found that serum miR-210 was significantly higher in CRC than in healthy controls (P < 0.001). The area under the receiver operating characteristic curve (AUC) of circulating miR-210 to detect CRC was 0.821, with a sensitivity of 74.6% and a specificity of 73.5%. The AUC of circulating miR-210 showed significantly higher detection capability than that of carcinoembryogenic antigen (P < 0.05). Kaplan-Meier analysis demonstrated that increased serum miR-210 level correlated with reduced overall survival (OS) and disease-free survival (DFS) (P = 0.008 and P = 0.008 respectively). Cox analysis indicated circulating miR-210 was an independent prognostic factor for OS and DFS. Taken together, our data suggested that circulating miR-210 could be a potential non-invasive marker for diagnosis and prognosis of CRC.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias do Colo/diagnóstico , MicroRNAs/metabolismo , Neoplasias Retais/diagnóstico , Idoso , Área Sob a Curva , Neoplasias do Colo/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias Retais/mortalidade , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Artigo em Zh | MEDLINE | ID: mdl-29081098

RESUMO

Objective: To observe the therapeutic efficacy of alanyl glutamine injection on patients with gastrointestinal function obstacle caused by severe phorate poisoning. Methods: A total of 80 eligible patients with gastrointestinal function obstacle caused by severe phorate poisoning were randomly divided into the control group (n=40) and treatment group (n=40) . The control group was treated with the conventional therapy, which included forbidden diet, atropine, pralidoxime iodide, anti-inflammatory, albumin infusion, ω-3 fish oil fat emulsion, protection of organs function, blood perfusion, and Fat Emulsion, Amino Acids (17) and Glucose Injection. The treatment group was treated with alanyl glutamine injection plus the conventional therapy. To observe the time of recovering to normal of gastrointestinal function between the two groups, compared the AChE activity and changes of prealbumin, albumin and total protein of the two groups respectively. Furthermore, the total atropine dosage, the total pralidoxime iodide dosage and ICU stay time between the two groups were also compared. Results: The gastrointestinal function recovery time of patients in the treatment group was less than the control group, the difference was statistically significant (P<0.05) . From the third day of treatment, the serum cholinesterase activity of the treatment group was higher than the control group, the difference was statistically significant (P<0.05) . On the 5th day and 10th day of the treatment, the prealbumin, albumin and total protein of the treatment group were significantly higher than these indexes of the control group in the same period, the difference were statistically significant (P<0.05) . The total atropine dosage, the total pralidoxime iodide dosage and ICU stay time in the treatment group were lower than the control group, the difference were statistically significant (P<0.05) . Conclusion: Alanyl glutamine injection has a great therapeutic effect for gastrointestinal function obstacle patients caused by severe phorate poisoning.


Assuntos
Atropina/administração & dosagem , Glutamina/administração & dosagem , Inseticidas/toxicidade , Obstrução Intestinal/tratamento farmacológico , Intoxicação por Organofosfatos/tratamento farmacológico , Forato/toxicidade , Glutamina/uso terapêutico , Humanos , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Sci Adv ; 8(23): eabm5180, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35675409

RESUMO

Quantum materials are notoriously sensitive to their environments, where small perturbations can tip a system toward one of several competing ground states. Graphene hosts a rich assortment of such competing phases, including a bond density wave instability ("Kekulé distortion") that couples electrons at the K/K' valleys and breaks the lattice symmetry. Here, we report observations of a ubiquitous Kekulé distortion across multiple graphene systems. We show that extremely dilute concentrations of surface atoms (less than three adsorbed atoms every 1000 graphene unit cells) can self-assemble and trigger the onset of a global Kekulé density wave phase. Combining complementary momentum-sensitive angle-resolved photoemission spectroscopy (ARPES) and low-energy electron diffraction (LEED) measurements, we confirm the presence of this density wave phase and observe the opening of an energy gap. Our results reveal an unexpected sensitivity of the graphene lattice to dilute surface disorder and show that adsorbed atoms offer an attractive route toward designing novel phases in two-dimensional materials.

9.
Biometrics ; 66(2): 393-404, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19673860

RESUMO

We propose a new estimation method for multivariate failure time data using the quadratic inference function (QIF) approach. The proposed method efficiently incorporates within-cluster correlations. Therefore, it is more efficient than those that ignore within-cluster correlation. Furthermore, the proposed method is easy to implement. Unlike the weighted estimating equations in Cai and Prentice (1995, Biometrika 82, 151-164), it is not necessary to explicitly estimate the correlation parameters. This simplification is particularly useful in analyzing data with large cluster size where it is difficult to estimate intracluster correlation. Under certain regularity conditions, we show the consistency and asymptotic normality of the proposed QIF estimators. A chi-squared test is also developed for hypothesis testing. We conduct extensive Monte Carlo simulation studies to assess the finite sample performance of the proposed methods. We also illustrate the proposed methods by analyzing primary biliary cirrhosis (PBC) data.


Assuntos
Interpretação Estatística de Dados , Método de Monte Carlo , Análise por Conglomerados , Simulação por Computador , Humanos , Cirrose Hepática Biliar , Fatores de Tempo
10.
Eur Rev Med Pharmacol Sci ; 24(12): 6583-6588, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32633346

RESUMO

OBJECTIVE: The purpose of this study was to detect the expression level of microRNA-210-3p (miRNA-210-3p) in cervical cancer (CC) tissues and its clinical significance. PATIENTS AND METHODS: Expression levels of miRNA-210-3p in collected CC tissues, normal cervical tissues and cervical intraepithelial neoplasia (CIN) tissues (CIN I, CIN II, and CIN III) were tested by reverse transcriptase-polymerase chain reaction (RT-PCR). The relationship between miRNA-210-3p level and clinical data of CC patients was analyzed. Moreover, the receiver operating characteristic (ROC) was introduced for assessing the diagnostic potential of miRNA-210-3p in CC. RESULTS: Results revealed that miRNA-210-3p level was higher in CC tissues relative to normal cervical tissues and CIN tissues. Its expression was not correlated with age, pathological subtype, and tumor size of CC patients. However, miRNA-210-3p level was closely linked to FIGO stage, tumor differentiation, and lymphatic metastasis in CC. Based on depicted ROC, miRNA-210-3p was able to distinguish CC from normal cervical tissues and CIN tissues. CONCLUSIONS: MiRNA-210-3p is upregulated in CC, and its level is closely correlated with FIGO stage, tumor differentiation, and lymphatic metastasis in CC patients. Besides, miRNA-210-3p produces a pronounced diagnostic efficacy, so it can be utilized as a novel hallmark for diagnosing CC and predicting the disease progression.


Assuntos
Biomarcadores Tumorais/biossíntese , Regulação Neoplásica da Expressão Gênica , MicroRNAs/biossíntese , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/genética , Colo do Útero/metabolismo , Colo do Útero/patologia , Feminino , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , Neoplasias do Colo do Útero/genética
11.
Sci Adv ; 5(11): eaaw5593, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31723598

RESUMO

Graphene is a powerful playground for studying a plethora of quantum phenomena. One of the remarkable properties of graphene arises when it is strained in particular geometries and the electrons behave as if they were under the influence of a magnetic field. Previously, these strain-induced pseudomagnetic fields have been explored on the nano- and micrometer-scale using scanning probe and transport measurements. Heteroepitaxial strain, in contrast, is a wafer-scale engineering method. Here, we show that pseudomagnetic fields can be generated in graphene through wafer-scale epitaxial growth. Shallow triangular nanoprisms in the SiC substrate generate strain-induced uniform fields of 41 T, enabling the observation of strain-induced Landau levels at room temperature, as detected by angle-resolved photoemission spectroscopy, and confirmed by model calculations and scanning tunneling microscopy measurements. Our work demonstrates the feasibility of exploiting strain-induced quantum phases in two-dimensional Dirac materials on a wafer-scale platform, opening the field to new applications.

12.
Eur J Pain ; 22(2): 370-384, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28984399

RESUMO

BACKGROUND: Human experimental pain models provide an important translational link between pre-clinical models and clinical pain. Using topical capsaicin and continuous heat application, the novel capsaicin/heat ongoing pain (CHOP) model induces long-lasting experimental pain of which the perceived intensity can be individually adjusted. METHODS: In the CHOP model, capsaicin or control cream is applied to a 10 × 10 cm skin area and a heating pad is applied over the area after cream removal. Two experiments in healthy participants were performed for model characterization. In Experiment 1, a constant temperature was applied for 60 min; in Experiment 2, temperature was adjusted to maintain a constant perceived intensity for 60 min. RESULTS: Experiment 1: across participants, constant temperature induced initial habituation followed by an increase in sensation back to baseline. Cluster analysis revealed that half the participants sensitized to the constant temperature, while the other half did not. The degree of sensitization was related to the baseline pain unpleasantness, relative to pain intensity. Experiment 2: constant perceived intensity was achieved in the painful and a non-painful control condition. The two conditions did not differ regarding possibly confounding variables, including blood pressure, heart rate, inflammation or physiological stress as measured by surrogate markers. Secondary allodynia and hyperalgesia were reported more following painful compared to control stimulation. Sensitizers as determined in Experiment 1 were also more pain sensitive in Experiment 2. CONCLUSION: The CHOP model reproduces some aspects of clinical pain, such as longer duration, sensitization, secondary allodynia and hyperalgesia. SIGNIFICANCE: Here we demonstrate a novel pain model that can be applied for up to an hour without tissue damage. The CHOP model allows for investigation of primary and secondary hyperalgesia as well as top-down influences on sensitization, thereby providing an experimental model that can be used to assess clinically-oriented questions.


Assuntos
Capsaicina , Temperatura Alta , Hiperalgesia/fisiopatologia , Dor/fisiopatologia , Pele/fisiopatologia , Adolescente , Adulto , Feminino , Voluntários Saudáveis , Humanos , Hiperalgesia/induzido quimicamente , Masculino , Dor/induzido quimicamente , Medição da Dor , Sensação , Adulto Jovem
13.
Structure ; 4(8): 931-42, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8805579

RESUMO

BACKGROUND: The integrin family of cell-surface receptors mediates a wide variety of cell-cell and cell-extracellular matrix interactions. Integrin-ligand interactions are invariably dependent on the presence of divalent cations, and a subset of integrins contain a approximately 200 amino acid inserted (I) domain that is important for ligand binding activity and contains a single divalent cation binding site. Many integrins are believed to respond to stimuli by undergoing a conformational change that increases their affinity for ligand, and there is a clear difference between two crystal structures of the CD11b I domain with different divalent cations (magnesium and manganese) bound. In addition to the different bound cation, a 'ligand mimetic' crystal lattice interaction in the CD11b I domain structure with bound magnesium has led to the interpretation that the different CD11b I domain structures represent different affinity states of I domains. The influence of the bound cation on I domain structure and function remains incompletely understood, however. The crystal structure of the CD11a I domain bound to manganese is known. We therefore set out to determine whether this structure changes when the metal ion is altered or removed. RESULTS: We report here the crystal structures of the CD11a I domain determined in the absence of bound metal ion and with bound magnesium ion. No major structural rearrangements are observed in the metal-binding site of the CD11a I domain in the absence or presence of bound manganese ion. The structures of the CD11a I domain with magnesium or manganese bound are extremely similar. CONCLUSIONS: The conformation of the CD11a I domain is not altered by changes in metal ion binding. The cation-dependence of ligand binding thus indicates that the metal ion is either involved in direct interaction with ligand or required to promote a favorable quaternary arrangement of the integrin.


Assuntos
Antígenos CD , Antígenos de Diferenciação , Antígenos CD18/química , Cátions Bivalentes/química , Antígeno-1 Associado à Função Linfocitária/química , Conformação Proteica , Sequência de Aminoácidos , Sítios de Ligação , Moléculas de Adesão Celular/metabolismo , Humanos , Ligação de Hidrogênio , Molécula 1 de Adesão Intercelular/metabolismo , Ligantes , Magnésio/química , Manganês/química , Modelos Moleculares , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/química
14.
J Gen Physiol ; 102(4): 729-60, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8270911

RESUMO

Phagocytes generate large amounts of metabolic acid during activation. Therefore, the presence of a conductive pathway capable of H+ extrusion has been suggested (Henderson, L. M., J. B. Chappell, and O. T. G. Jones. 1987. Biochemical Journal. 246:325-329). In this report, electrophysiological and fluorimetric methods were used to probe the existence of a H+ conductance in murine peritoneal macrophages. In suspended cells, recovery of the cytosolic pH (pHi) from an acid-load in Na+ and HCO3(-)-free medium was detectable in depolarizing but not in hyperpolarizing media. The rate of alkalinization was potentiated by the rheogenic ionophore valinomycin. These findings are consistent with the existence of a conductive H+ (equivalent) pathway. This notion was confirmed by patch-clamping and fluorescence ratio measurements of single adherent cells. When voltage was clamped in the whole-cell configuration, depolarizing pulses induced a sizable outward current which was accompanied by cytosolic alkalinization. Several lines of evidence indicate that H+ (equivalents) carry this current: (a) the conductance was unaffected by substitution of the major ionic constituents of the intra-and/or extracellular media, (b) the reversal potential of the tail currents approached the H+ equilibrium potential; and (c) the voltage-induced currents and pHi changes were both Zn2+ sensitive and had similar time course and potential dependence. The peak whole-cell current displayed marked outward rectification and was exquisitely H+ selective. At constant voltage, the H+ permeability was increased by lowering pHi but was inhibited by extracellular acidification. Together with the voltage dependence of the conductance, these features ensure that H+ extrusion can occur during activation, while potentially deleterious acid uptake is precluded. The properties of the conductance appear ideally suited for pHi regulation during phagocyte activation, because these cells undergo a sustained depolarization and an incipient acidification when stimulated. Comparison of the magnitude of the current with the amount of metabolic acid generated during macrophage activation indicates that the conductance is sufficiently large to contribute to the H+ extrusion required for maintenance of pHi.


Assuntos
Membrana Celular/fisiologia , Macrófagos Peritoneais/fisiologia , Prótons , Animais , Membrana Celular/metabolismo , Condutividade Elétrica , Eletrofisiologia , Concentração de Íons de Hidrogênio , Macrófagos Peritoneais/metabolismo , Camundongos
15.
Clin Genitourin Cancer ; 13(1): 71-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24993933

RESUMO

BACKGROUND: The differential impact of the number of prior lines of therapy and the setting of prior therapy (perioperative or metastatic) is unclear in advanced urothelial carcinoma. PATIENTS AND METHODS: Ten phase II trials of salvage chemotherapy, biologic agent therapy, or both, enrolling 731 patients, were available. Data on the number of prior lines of therapy and the setting of prior therapy were required in addition to known previously recognized prognostic factors: time from prior chemotherapy, hemoglobin level, performance status, and liver metastasis status. Cox proportional hazards regression was used to evaluate the association of the number of prior lines and prior perioperative therapy with overall survival (OS) as the primary clinical endpoint. Trial was a stratification factor. RESULTS: A total of 711 patients were evaluable. The overall median progression-free survival and OS were 2.7 and 6.8 months, respectively. The number of prior lines was 1 in 559 patients (78.6%), 2 in 111 (15.6%), 3 in 29 (4.1%), 4 in 10 (1.4%), and 5 in 2 (0.3%). Prior perioperative chemotherapy was given to 277 (39.1%) and chemotherapy for metastatic disease to 454 (64.1%). The number of prior lines was not independently associated with OS (hazard ratio, 0.99; 95% CI, 0.86-1.14). Prior perioperative chemotherapy was a favorable factor for OS on univariate but not multivariate analysis. CONCLUSION: The number of prior lines of therapy and prior perioperative chemotherapy were not independently prognostic in patients with urothelial carcinoma receiving salvage therapy. Adoption of these data in salvage therapy trials should enhance accrual, the interpretability of results, and drug development.


Assuntos
Tratamento Farmacológico/métodos , Terapia de Salvação/métodos , Neoplasias Urológicas/tratamento farmacológico , Neoplasias Urológicas/mortalidade , Idoso , Ensaios Clínicos Fase II como Assunto , Humanos , Pessoa de Meia-Idade , Assistência Perioperatória , Estudos Prospectivos , Análise de Regressão , Análise de Sobrevida , Resultado do Tratamento
16.
Brain Res ; 939(1-2): 65-75, 2002 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-12020852

RESUMO

Accumulation of beta-amyloid (Abeta) protein in brain is an important characteristic for the etiology of Alzheimer's disease. Of all the possible processes generating the neurotoxic effects by Abeta, disruption of intracellular Ca(2+) homeostasis is the primary event. In this process, various intracellular Ca(2+) regulatory mechanisms are reported to be involved. Using patch-clamp techniques, both low and high voltage activated Ca(2+) channel currents were recorded in the cultured dorsal root ganglion (DRG) neurons. Application of Abeta protein fragment, Abeta(25-35) (2 microM), for 30 s increased the amplitude in both currents. The Abeta-triggered facilitation effect of Ca(2+) channel was found in all the depolarized potentials tested, as shown in the current-voltage relationship. Furthermore, after applying single cell Ca(2+) microfluorometric method, it was found that Abeta(25-35) alone could trigger elevations of intracellular Ca(2+) concentration ([Ca(2+)](i)) level in 90% of the cells tested. The elevation diminished completely by cumulatively adding CdCl(2), NiCl(2), thapsigargin (TG), FCCP and Zn(2+) in the normal bath solution. Combining pharmacological approaches, we found that voltage-dependent Ca(2+) channels, Ca(2+) stores and a putative Zn(2+)-sensitive extracellular Ca(2+) entry, respectively, makes 61.0, 25.1, and 13.9% contribution to the [Ca(2+)](i) increase caused by Abeta. When tested in a Ca(2+)-free buffer, mitochondria was found to contribute 41.3% of Abeta produced [Ca(2+)](i) elevation and the remaining 58.7% was attributed to endoplasmic reticulum (ER) release.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Canais de Cálcio/efeitos dos fármacos , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Técnicas de Cultura de Células , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Inibidores Enzimáticos/farmacologia , Homeostase/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Técnicas de Patch-Clamp , Fragmentos de Peptídeos/farmacologia , Ratos , Ratos Wistar , Tapsigargina/farmacologia , Desacopladores/farmacologia
17.
J Chromatogr A ; 934(1-2): 13-29, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11762761

RESUMO

Since experimental methods for measuring multicomponent adsorption isotherms are extremely tedious, numerical approaches are an attractive alternative. Here, the variance in isotherm parameters as a function of experimental error in measured effluent concentrations is quantified. The number of experimental replicates needed to obtain isotherm parameters to a desired level of accuracy is calculated explicitly. After the covariance matrix of the parameters has been determined, Monte Carlo methods are found to be rapid and effective. The use of different kinds of experiments, the effect of resolution and loading, and the impact of the number of measured data points are described.


Assuntos
Cromatografia Líquida/métodos , Adsorção , Modelos Químicos , Reprodutibilidade dos Testes , Termodinâmica
18.
Int J Gynaecol Obstet ; 87(2): 199-202, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15491580

RESUMO

OBJECTIVE: To determine the rates of repeated abortion and contraceptive use among unmarried young women seeking an abortion in China. METHODS: We used an anonymous self-administered questionnaire at abortion clinics in Beijing, Changsha, and Dalian from January to September 2000. RESULTS: Of 4547 unmarried young women seeking an abortion, 33.0% reported having had one previous induced abortion. Of those who had had more than one abortion, only 29.7% used a contraceptive method at their first sexual intercourse after the procedure; and of the 446 women who chose contraception, 41.3% used the traditional methods of withdrawal or rhythm. Although 65.0% of the young women had used condoms at least once, only 9.6% did so consistently and correctly; 47.7% of the current pregnancies were associated with nonuse of any contraceptive, and 52.3% were related to contraceptive failure. CONCLUSION: The rate of unmarried young women seeking repeated abortions was high in China on 2000. The rate of consistent condom use was low, and the rate of contraceptive failure was higher.


Assuntos
Aborto Induzido/estatística & dados numéricos , Comportamento Contraceptivo/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , China/epidemiologia , Feminino , Humanos , Estado Civil , Gravidez , Inquéritos e Questionários
19.
Sheng Li Xue Bao ; 52(2): 98-102, 2000 Apr.
Artigo em Zh | MEDLINE | ID: mdl-11961576

RESUMO

Using perforated and cell-attached patch clamp techniques, the characteristics of ATP sensitive K(+) channels (K(ATP)), delayed rectifier K(+) channels (K(DR)), Ca(2+) and Na+ channels on single rat pancreatic beta cell membranes were studied. The results showed that (1) the efflux and influx conductance of K(ATP) channels was about 31 and 65 pS respectively, and the reversal potential of K(ATP) was about 60 mV; (2) K(DR) was activated completely after a latency of 20 ms, and K(DR) was about 1/3 of K(ATP); (3) whole cell Ca(2+) current reached a peak (40 60 pA) at 0 mV; L-type Ca(2+) channel was the main Ca(2+) channel in beta cells, but other types of high voltage activated Ca(2+) channels existed as well; and 4) whole cell Na(+) current reached a peak (200 400 pA) at 10 mV; but the expression level of Na(+) channel in beta cells varied among the cells. About half of the beta cells virtually had no Na(+) currents.


Assuntos
Canais de Cálcio/metabolismo , Ilhotas Pancreáticas/metabolismo , Canais de Potássio/metabolismo , Canais de Sódio/metabolismo , Animais , Células Cultivadas , Ilhotas Pancreáticas/citologia , Técnicas de Patch-Clamp , Ratos , ATPase Trocadora de Sódio-Potássio/metabolismo
20.
Sheng Li Xue Bao ; 51(6): 692-9, 1999 Dec.
Artigo em Zh | MEDLINE | ID: mdl-11498941

RESUMO

Carbon fiber electrode (CFE) can be used in detection of exocytosis of single neuron or endocrine cell. A simplified method for preparation of CFE, as described in the present paper, greatly ensures the coordination and success of the preparation. Such CFEs have a low noise level. Exocytosis of rat adrenal chromaffin cells was investigated in the clarification of the effect of MPP+ on transmitter release. It is found that exocytosis was not stimulated by MPP+ and the high K+ induced secretion was not changed by MPP+. These observations suggest that the previously reported elevation of dopamine content in the surrounding histosolution of DA neuron is probably resulted from blockage of the re-uptake of DA by MPP+.


Assuntos
1-Metil-4-fenilpiridínio/farmacologia , Células Cromafins/metabolismo , Eletrodos/classificação , Exocitose/fisiologia , Medula Suprarrenal/metabolismo , Animais , Carbono , Eletroquímica , Ratos , Ratos Wistar
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