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1.
Zhonghua Nei Ke Za Zhi ; 60(3): 243-246, 2021 Mar 01.
Artigo em Chinês | MEDLINE | ID: mdl-33663174

RESUMO

To investigate the clinical significance of serum soluble programmed cell death ligand-1 (PD-L1) in adult patients with community-acquired pneumonia (CAP). A total of 44 CAP patients, 54 severe CAP patients and 30 healthy volunteers were recruited in this study. Serum soluble PD-L1 were detected. Univariate and multivariate regression analyses were used to assess the influence of multiple clinical variables on prognosis. Serum soluble PD-L1 level in severe CAP group was 98.20(57.94, 128.90) ng/L, which was significantly higher than that in the CAP group [59.32(33.55, 92.58) ng/L] and healthy controls [20.44(12.15, 36.20) ng/L] (all P<0.001). PD-L1 level was positively correlated with CRUB-65(r=0.481, P<0.001) and the pneumonia severity index (PSI) score (r=0.442, P<0.001). Univariate regression analysis showed that CURB-65 (HR=2.544, 95%CI 1.324-4.889, P=0.005), PSI score (HR=1.036, 95%CI 1.012-1.061, P=0.004), soluble PD-L1(HR=1.013, 95%CI 1.001-1.026, P=0.041) were risk factors of mortality during hospitalization. Multivariate regression analysis suggested that PSI score (HR=1.042, 95%CI 1.012-1.073, P=0.005), soluble PD-L1 (HR=1.011, 95%CI 1.002-1.071, P=0.020) were independent predictors for mortality risk in CAP patients. CAP patients with soluble PD-L1≥98.20 ng/L had a significantly lower survival rate than those with soluble PD-L1<98.20 ng/L (P=0.033). In conclusion, this study indicates that serum soluble PD-L1 level in CAP patients is correlated with the survival prognosis.


Assuntos
Antígeno B7-H1 , Pneumonia , Adulto , Apoptose , Humanos , Ligantes , Prognóstico
2.
Eur J Neurol ; 27(11): 2233-2241, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32562320

RESUMO

BACKGROUND AND PURPOSE: Migraine is a complex and disabling neurological disorder, the exact neurological mechanisms of which remain unclear. The thalamus is considered to be the hub of the central processing and integration of nociceptive information, as well as the modulation of these processes. METHODS: A total of 48 migraineurs without aura (MWoAs) during the interictal phase and 48 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging scans. We utilized masked independent component analysis and seed-based functional connectivity (FC) to investigate whether MWoAs exhibited abnormal FC between subregions in the thalamus and the cortex regions. RESULTS: The MWoAs showed significantly weaker FC between the anterior dorsal thalamic nucleus and left precuneus. Additionally, MWoAs exhibited significantly reduced FC between the ventral posterior nucleus (VPN) and left precuneus, right inferior parietal lobule (R-IPL) and right middle frontal gyrus. Furthermore, the FC Z-scores between the VPN and R-IPL were negatively correlated with pain intensity in MWoAs. The disease duration of patients was negatively correlated with the FC Z-scores between the VPN and R-IPL. CONCLUSION: These altered thalamocortical connectivity patterns may contribute to multisensory integration abnormalities, deficits in pain attention, cognitive evaluation and pain modulation. Pain sensitivity and disease duration are closely tied to abnormal FC between the VPN and R-IPL. Remarkably, recurrent headache attacks might contribute to this maladaptive functional plasticity closely related to pain intensity.


Assuntos
Enxaqueca sem Aura , Córtex Cerebral/diagnóstico por imagem , Epilepsia , Humanos , Imageamento por Ressonância Magnética , Enxaqueca sem Aura/diagnóstico por imagem , Tálamo/diagnóstico por imagem
3.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(6): 456-460, 2020 Jun 24.
Artigo em Chinês | MEDLINE | ID: mdl-32171190

RESUMO

Objective: To analyze the clinical characteristics of the severe or critically ill patients with novel coronavirus pneumonia (COVID-19), and evaluate the impact of complicated myocardial injury on the prognosis of these patients. Methods: A retrospective study was conducted in 54 patients who admitted to Tongji hospital from February 3, 2020 to February 24, 2020 and met the criteria of severe or critical conditions of COVID-19. The clinical characteristics and hospital mortality rate were analyzed and compared between the patients with or without myocardial injury, which was defined with 3 times higher serum cardiac troponin value. Results: The age of the 54 patients was 68.0(59.8, 74.3) years. Among all the patients, 24 (44.4%) patients were complicated with hypertension, 13 (24.1%) with diabetes, 8 (14.8%) with coronary heart disease, and 3 (5.6%) with previous cerebral infarction. During hospitalization, 24 (44.4%) of the patients were complicated with myocardial injury and 26 (48.1%) patients died in hospital. In-hospital mortality was significantly higher in patients with myocardial injury than in patients without myocardial injury (14 (60.9%) vs. 8 (25.8%), P=0.013). Moreover, the levels of C-reactive protein (153.6 (80.3, 240.7) ng/L vs. 49.8 (15.9, 101.9) ng/L) and N-terminal pro-B-type natriuretic peptide (852.0 (400.0, 2 315.3) ng/L vs. 197.0 (115.3, 631.0) ng/L) were significantly higher than patients without myocardial injury (all P<0.01). Conclusions: Prevalence of myocardial injury is high among severe or critically ill COVID-19 patients. Severe or critically ill COVID-19 patients with myocardial injury face a significantly higher risk of in-hospital mortality. The study suggests that it is important to monitor and manage the myocardial injury during hospitalization for severe or critically ill COVID-19 patients.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Estado Terminal , Traumatismos Cardíacos , Pandemias , Pneumonia Viral , Idoso , COVID-19 , Infecções por Coronavirus/complicações , Humanos , Pessoa de Meia-Idade , Pneumonia Viral/complicações , Estudos Retrospectivos , SARS-CoV-2
4.
Zhonghua Yi Xue Za Zhi ; 99(38): 2976-2981, 2019 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-31607028

RESUMO

Objective: To explore the expression and clinical significance of chemokine ligand 18 (CCL18) in Bronchoalveolar Lavage Fluid (BALF) of patients with connective tissue disease-associated interstitial lung disease (CTD-ILD). Methods: From January 2016 to June 2017, BALF of patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD group), patients with dermatomyositis-associated interstitial lung disease (DM-ILD group), and patients with primary Sjögren syndrome-associated interstitial lung disease (pSS-ILD group) of Peking University People's Hospital were collected. According to the prognosis of each group of patients during hospitalization, they were divided into the discharged and the died. Besides, 30 patients without ILD served as a control group. Levels of CCL18 in BALF of all patients were tested by enzyme linked immunosorbent assay (ELISA). Cells in BALF of RA-ILD group, DM-ILD group and pSS-ILD group were collected and analyzed by absolute different cell counts. Results of high-resolution CT (HRCT) of these three groups were scored. In addition, the area under the curve (AUC) of CCL18 in predicting mortality during hospitalization was calculated. Results: A total of 38 patients with RA-ILD, 54 patients with DM-ILD, and 35 patients with pSS-ILD were enrolled. Levels of CCL18 of those discharged patients of RA-ILD, DM-ILD, and pSS-ILD groups were 8.27(3.62, 14.36), 11.04 (5.86, 17.38), 5.25(2.68, 8.21) µg/L, respectively, which were all significantly higher than that of the control group [2.54(1.26, 3.66) µg/L, all P<0.05]. Furthermore, levels of CCL18 of those deceased patients of RA-ILD and DM-ILD groups were 18.28 (13.82, 22.39), 18.81 (16.29, 22.90) µg/L, which were significantly higher than that of the discharged patients of same group (all P<0.05). Levels of CCL18 were positively correlated with lymphocyte percentage in BALF of RA-ILD, DM-ILD and pSS-ILD groups (r=0.4356, 0.4029, 0.3939, respectively, all P<0.05). Besides, levels of CCL18 were significantly correlated with HRCT scores of RA-ILD and DM-ILD groups (r=0.4242, 0.3319, respectively, both P<0.05). Areas under the curve (AUCs) of CCL18 to predict mortality during hospitalization of RA-ILD and DM-ILD groups were 0.860, 0.851, respectively. Conclusions: Levels of CCL18 are elevated in BALF of CTD-ILD patients, and may be correlated with the severity and prognosis during hospitalization. CCL18 might be served as an indicator of the severity and prognosis of CTD-ILD.


Assuntos
Doenças do Tecido Conjuntivo , Dermatomiosite , Doenças Pulmonares Intersticiais , Líquido da Lavagem Broncoalveolar , Quimiocinas , Quimiocinas CC , Doenças do Tecido Conjuntivo/metabolismo , Humanos , Doenças Pulmonares Intersticiais/etiologia
5.
Zhonghua Wai Ke Za Zhi ; 57(8): 572-577, 2019 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-31422625

RESUMO

Objective: To examine the effect of standardized lymphectomy and sampling of resected lymph nodes (LN) on TNM staging of resectable pancreatic head cancer. Methods: Consecutive patients with resectable pancreatic head cancer who received standard pancreatoduodenctomy at Department of General Surgery in Beijing Hospital from December 2017 to November 2018 were recruited as study group. After operation, the surgeon sampled lymph nodes from the fresh specimen following the Japanese Gastric Cancer Guidelines.Thirty-three cases were recruited in the study group and the mean age was (59.8±15.2) years.Pathologic reports from December 2015 to November 2016 were taken as control group, containing 29 cases with age of (57.0±13.0) years. Number of lymph nodes, standard-reaching ratio and positive nodes ratio were compared between two groups. According to the seventh edition and eighth edition of TNM staging, the changes of N staging and TNM staging were analysed. The quantitative data conforming to normal distribution were tested by independent sample t test, the quantitative data not conforming to normal distribution were tested by rank sum test, and the enumeration data were analysed by χ(2) test. Results: The basal data of the two groups were comparable (all P>0.05) . The number of lymph nodes sampled in the study group was 23.27±8.87, significantly more than in control group (12.86±5.90, t=0.653, P=0.000) .Ratio of cases with more than 15 nodes was 81.8% (27/33) in the study group and 34.5% (10/29) in the control group with statistical significance (χ(2)=14.373, P=0.000) . In the study group, the positive lymph node ratios of No. 17a+17b, 14a+14b, 8a+8p LN were 36.4% (12/33) , 30.3% (10/33) and 9.1% (3/33) respectively. The positive lymph node ratio in No.14a+14b LN was higher than in No.8 LN (χ(2)=4.694, P=0.030) . According to the change in N staging system in the AJCC eighth edition, 2 cases (6.1%, 2/33) changed from ⅠB to ⅡA, 7 cases (21.2%, 7/33) from ⅡA to ⅠB and 5 cases (15.2%, 5/33) changed from ⅡB to Ⅲ (25.0%, 5/20) . Conclusions: No.14 LN should be treated as the first station rather than second station because of the anatomic character and higher metastatic ratio. Standardised lymphectomy and sampling may increase the number of LN resected and improve the TNM staging of resectable pancreatic head cancer.


Assuntos
Excisão de Linfonodo/normas , Linfonodos/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/normas , Adulto , Idoso , Humanos , Excisão de Linfonodo/métodos , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Pancreaticoduodenectomia/métodos , Prognóstico
6.
J Chem Phys ; 149(20): 204310, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30501263

RESUMO

Two-dimensional (2D) and three-dimensional (3D) Cu n clusters (n indicates the atom number) and their adsorption behaviors for both methane (CH4) and methyl (CH3) are studied in this work using the density functional theory method, where n ranges from 6 to 20. In these small clusters, it is found that the CH4 molecule is always adsorbed on the top site with the adsorption energy between -0.05 eV and -0.21 eV. Considering methane dehydrogenation, stronger adsorption for CH4 is required, so 2D clusters with n = 7, 14, 15, and 16 and 3D clusters with n = 6, 10, 12, and 17 are found to have relatively stronger adsorption. However, for the adsorption of CH3, there is an obvious even-odd oscillation change in the size of 3D clusters, while it is not clear in 2D clusters since one cannot find an even-odd change as n > 14. The weaker adsorption for CH3 occurs on 3D clusters when n is even except 6 and also on 2D clusters when n = 6, 7, 10, and 12 with higher carbon poisoning resistance. Based on these calculated results, some Cu clusters which show good potential ability for methane dehydrogenation are provided, especially when n = 10 and 12 for 3D structures, and n = 7 for the 2D ones.

8.
Phys Chem Chem Phys ; 19(41): 28056-28062, 2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-28994837

RESUMO

Significant variations in Raman shifts with decreasing material size, D, have been detected in Raman spectroscopy. In this study, we propose a simple and unified model to determine and explain the size-dependent Raman shift, ω(D), of low-dimensional semiconductor nanomaterials. ω(D) was found to be a function of bond number in a system, with an obvious decline in Raman shift observed when size dropped to the nanoscale. This arose from a decrease in coordination number, Z(D), and increase in single bond strength, ε(D). The predicted results show good agreement with experimental data for a series of semiconductor nanomaterials, showing that bond number can be used to calculate Raman shifts of nanomaterials. Moreover, this theoretical model was successfully applied to both single crystals and some binary semiconductor nanomaterials. Furthermore, bond number, which is directly related to the nanomaterial shape and size, becomes the only parameter required to determine ω(D) in this model, as both Z(D) and ε(D) can be determined from the bond number. This indicates that the established model has the potential to determine Raman shifts of nanomaterials with different shapes and sizes.

10.
Zhonghua Wai Ke Za Zhi ; 54(9): 664-8, 2016 Sep 01.
Artigo em Chinês | MEDLINE | ID: mdl-27587208

RESUMO

OBJECTIVE: To explore the application of the technique of terminal branches portal vein embolization(TBPVE)for planed hepatectomy. METHODS: From February 2016 to June 2016, 4 patients with hepatocellular carcinoma underwent TBPVE and liver resection in Yuebei People's Hospital (n=3) and Jiangxi Ji'an Central People's Hospital (n=1). All of them were male and were 50, 64, 39 and 47 years old respectively. All the tumors located in the right lobe. All patients had the liver function of Child-Pugh A classification and liver cirrhosis level of G2S4. The standard liver volume (SLV) were 1 291, 1 109, 1 177 and 1 242 ml and estimated future liver remnant(FLR) were 315, 347, 306 and 323 ml respectively. The puncture site of TBPVE was determined by the three-dimensional reconstruction of portal vein. Three patients were punctured in the segment Ⅵ and the other one punctured in the segment Ⅲ. CT scan was repeated 2 weeks after TBPVE and FLR and FLR/SLV were calculated. All patients underwent right hepatectomy 2 weeks after TBPVE. RESULTS: On the 14(th) day after TBPVE, the FLR of 4 patients were 529, 462, 469 and 498 ml which increased 67.9%, 33.1%, 53.3% and 54.2% compared with that before TBPVE, and FLR/SLV were 41.0%, 41.7%, 39.8% and 40.1% respectively. No severe complication occurred. Right hepatectomy were performed 2 weeks after TBPVE. No inflow blood control applied during the liver resection. The mean blood loss was 950 ml and the mean operating time was 3.3 hours (ranging from 3 to 4 hours). One patient had respiratory infection and two had slight jaundice and ascites for a short period. No other complication occurred. CONCLUSION: The TBPVE could induce a rapid and large FLR volume that give chances to patients with small FLR to have liver resection for hepatocellular carcinoma.


Assuntos
Embolização Terapêutica , Hepatectomia/métodos , Veia Porta , Idoso , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Anal Bioanal Chem ; 405(21): 6639-48, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23807307

RESUMO

In this study, a boronate-silica hybrid affinity monolith was prepared for specific capture of glycoproteins at neutral pH condition. The monolith was synthesized via a facile one-pot procedure in a stainless steel column by concurrently mixing hydrolyzed alkoxysilanes tetramethoxysilane and vinyltrimethoxysilane, organic monomer 3-acrylamidophenylboronic acid and initiator 2,2'-azobisisobutyronitrile together. The polycondensation of alkoxysilanes and copolymerization of organic monomer and vinyl-silica monolith were carried out successively by reacting at different temperatures. After optimizing the preparation conditions, the resulting hybrid affinity monolith was systematically characterized and exhibited excellent affinity to both cis-diol-containing small molecules and glycoproteins at neutral and physiological pH, including adenosine, horseradish peroxidase, transferrin and ovalbumin. The binding capacity of ovalbumin on monolith was measured to be 2.5 mg g(-1) at pH 7.0. Furthermore, the hybrid affinity monolith was applied to the separation of transferrin from bovine serum sample at a physiological condition. Good repeatability was obtained and the relative standard deviations of retention time were 1.15 and 4.77 % (n = 5) for run-to-run and column-to-column, respectively.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Ácidos Borônicos/síntese química , Cromatografia de Afinidade/métodos , Glicoproteínas/química , Glicoproteínas/isolamento & purificação , Microquímica/métodos , Dióxido de Silício/síntese química
12.
Anal Bioanal Chem ; 405(15): 5321-31, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23552973

RESUMO

A novel strategy for preparation of a boronate affinity hybrid monolith was developed using a Cu(I)-catalyzed 1,3-dipolar azide-alkyne cycloaddition (CuAAC) reaction of an alkyne-boronate ligand with an azide-functionalized monolithic intermediate. An azide-functionalized hybrid monolith was first synthesized via a single-step procedure to provide reactive sites for click chemistry; then the alkyne-boronate ligands were covalently immobilized on the azide-functionalized hybrid monolith via an in-column CuAAC reaction to form a boronate affinity hybrid monolith under mild conditions. The boronate affinity monolith was characterized and evaluated by means of elemental analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The boronate affinity hybrid monolith exhibited excellent specificity toward nucleosides and glycoproteins, which were chosen as test cis-diol-containing compounds under neutral conditions. The binding capacity of the monolith for the glycoprotein ovalbumin was 2.36 mg · g(-1) at pH 7.0. The practicability of the boronate affinity hybrid monolithic material was demonstrated by specific capture of the glycoproteins ovalbumin and ovotransferrin from an egg sample.


Assuntos
Ácidos Borônicos/química , Cromatografia de Afinidade/métodos , Glicoproteínas/química , Estrutura Molecular , Ligação Proteica
13.
Eur Surg Res ; 42(2): 130-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19174608

RESUMO

AIM: The mechanism of hyperbaric oxygen (HBO) therapy for acute pancreatitis has not been fully clarified yet. The main purpose of this study was to investigate the effect of HBO on nuclear factor kappaB (NF-kappaB) activation and the inflammatory response in rats with acute necrotizing pancreatitis (ANP). METHODS: A total of 120 male Sprague-Dawley rats were randomly divided into 3 groups (40 in each): control, ANP and ANP + HBO. ANP rat models were established by a retrograde injection of 5% sodium taurocholate into the pancreatic duct. HBO treatment was performed at 2.5-fold absolute atmospheric pressure in 90% oxygen for 1, 3, 5, and 7 h. The activation of NF-kappaB and its inhibitor IkappaBalpha in peripheral blood neutrophilic granulocytes was measured by electrophoretic mobility shift assay and Western blot, respectively. The inflammatory cytokines [interleukin (IL)-2, IL-6, tumor necrosis factor-alpha (TNF-alpha), and intercellular adhesion molecule 1] in the blood were measured by enzyme-linked immunosorbent assay. RESULTS: The blood levels of inflammatory cytokines and NF-kappaB activation were significantly increased in ANP rats compared to control rats, but IkappaBalpha activation was suppressed. The levels of the elevated inflammatory cytokines were positively correlated with the changes in NF-kappaB activation. After HBO treatment, the blood levels of inflammatory cytokines and NF-kappaB activation were significantly decreased in the ANP + HBO group in a time-dependent manner, but IkappaBalpha activation was increased. CONCLUSION: Our findings suggest that acute pancreatitis is associated with the upregulation of cytokines in blood as well as upregulation of NF-kappaB levels and downregulation of IkappaBalpha activation in peripheral blood neutrophilic granulocytes. In contrast, HBO plays a role in acute pancreatitis treatment by normalizing these changes.


Assuntos
Biomarcadores/sangue , Oxigenoterapia Hiperbárica , NF-kappa B/sangue , Pancreatite Necrosante Aguda/terapia , Amilases/urina , Animais , Ascite/enzimologia , Ativação Enzimática , Proteínas I-kappa B/sangue , Molécula 1 de Adesão Intercelular/sangue , Interleucina-2/sangue , Interleucina-6/sangue , Masculino , Inibidor de NF-kappaB alfa , Neutrófilos/enzimologia , Pâncreas/patologia , Pancreatite Necrosante Aguda/sangue , Pancreatite Necrosante Aguda/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/sangue
14.
Transplant Proc ; 40(5): 1792-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18589199

RESUMO

Liver transplantation (OLT) in an adult with situs inversus (SI) is extremely rare and considered a contraindication because of the anatomic difficulties. A 45-year-old male patient with complete SI, suffering from progressive hepatic failure secondary to hepatolithiasis, obstructive jaundice, and liver cirrhosis, underwent transplantation in July 2004. Preoperatively the liver anatomy was determined by computed tomography scan, three-dimensional liver reconstruction, and angiography. OLT was performed using a modified piggyback technique, the donor right lobe was rotated 45 degrees to the left, making the donor left lobe point into the left paracolic sulcus and the donor right lobe in the recipient hepatic fossa. The donor's suprahepatic vena cava was sewn end to side to the recipient vena cava, and the infrahepatic vena cava oversewn. The patient recovered uneventfully, and transplant perfusion and function were stable at a follow-up of 40 months. The present study showed OLT in adult patients with SI to be feasible. The knowledge of exact anatomy, meticulous preoperative planning, and optimization of the recipients condition are essential.


Assuntos
Transplante de Fígado , Fígado/anatomia & histologia , Situs Inversus/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Fígado/diagnóstico por imagem , Falência Hepática/etiologia , Falência Hepática/cirurgia , Masculino , Pessoa de Meia-Idade , Situs Inversus/complicações , Tomografia Computadorizada por Raios X , Resultado do Tratamento
15.
J Clin Invest ; 89(2): 673-80, 1992 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1371126

RESUMO

Production of autoantibodies specific for the Fc region of autologous IgG, called rheumatoid factors (RF), is a characteristic finding in patients with rheumatoid arthritis (RA). To study the requirements regulating the synthesis of these autoantibodies, we have cloned human helper T cells and co-cultured them with purified B cells. To mimic cognate T-B cell interaction, we have used bacterial superantigens that function by cross-linking HLA molecules on the B cell with selected T cell receptor (TCR) molecules expressing a particular polymorphism of the V beta gene segment. Data presented here demonstrate that the staphylococcal enterotoxin D (SE D), but not other bacterial superantigens, exhibits an ability to induce IgM, IgG, and especially RF production, in B cells from RA patients and normal individuals. Comparison with the polyclonal antibody production in B cell cultures driven by anti-CD3-stimulated T cell clones confirmed that SE D shifted the repertoire of secreted antibodies toward immunoglobulins with Fc binding specificity, suggesting that SE D preferentially stimulates RF+ B lymphocytes. B cells with the potential to secrete RF were highly frequent in RA patients, requiring as few as 150 peripheral B cells/culture to detect RF in the culture supernatants. SE D-induced RF synthesis was strictly dependent on the presence of selected CD4+T helper cells and required a direct membrane contact between B cells and T helper cells. Here, we propose a model that SE D selectively induces RF production depending on the availability of SE D responsive T cells in the TCR repertoire of the responder.


Assuntos
Antígenos de Bactérias/imunologia , Enterotoxinas/imunologia , Fator Reumatoide/biossíntese , Linfócitos T Auxiliares-Indutores/imunologia , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/imunologia , Artrite Reumatoide/imunologia , Linfócitos B/fisiologia , Complexo CD3 , Antígenos CD5 , Antígenos HLA-DR/análise , Humanos , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/fisiologia
16.
J Biomed Opt ; 4(1): 164-75, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23015182

RESUMO

Coherent light scattered from an ensemble of moving scatterers produces a time-varying speckle pattern. The intensity fluctuations observed in a single speckle can be regarded either as a time-varying interference effect or as a Doppler beating effect. Techniques based on each of these approaches have been developed to analyze the fluctuations in an attempt to measure the velocities of the scatterers. Most of these methods measure the temporal statistics of the intensity fluctuations in a single speckle, i.e., at a single point. If a map of the velocity distribution is required, some form of scanning must be introduced. One way of avoiding the need to scan is to make use of the spatial statistics of time-integrated speckle. This is the basis of a technique, already described in the literature, called laser speckle contrast analysis (LASCA). In this article, we present a brief review of the theory linking the intensity fluctuations to the velocity and of the various techniques that have been proposed to measure them. We then describe the present configuration of our LASCA technique and describe some recent developments in our search for a real-time, noninvasive, full-field technique for visualizing capillary blood flow. © 1999 Society of Photo-Optical Instrumentation Engineers.

17.
Talanta ; 44(6): 959-65, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18966826

RESUMO

A single piezoelectric quartz crystal coated with one kind of crown ether was applied to the simultaneous determination of binary acid and amine vapor mixtures. From the adsorption and desorption curves of analytes, which were somewhat different in shape, frequency shifts from ten time windows were taken as inputs for artificial neural networks (ANN). Prediction results were satisfactory for ANN in both sample sets. The average relative errors, for formic acid and acrylic acid were 5%, for n-butylamine and aniline, they were 3% with ANN respectively. The effects of number of neurons in the hidden layer of ANN on the performance of the network are also discussed.

18.
Talanta ; 44(11): 2033-9, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18966950

RESUMO

A promising way of increasing the selectivity and sensitivity of gas sensors is to treat the signals from a number of different gas sensors with pattern recognition (PR) method. A gas sensor array with seven piezoelectric crystals each coated with a different partially selective coating material was constructed to identify four kinds of combustible materials which generate smoke containing different components. The signals from the sensors were analyzed with both conventional multivariate analysis, stepwise discriminant analysis (SDA), and artificial neural networks (ANN) models. The results show that the predictions were even better with ANN models. In our experiment, we have reported a new method for training data selection, 'training set stepwise expending method' to solve the problem that the network can not converge at the beginning of the training. We also discussed how the parameters of neural networks, learning rate eta, momentum term alpha and few bad training data affect the performance of neural networks.

19.
IEEE Trans Neural Netw ; 6(4): 929-40, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-18263381

RESUMO

Conventional associative memory networks perform "noncompetitive recognition" or "competitive recognition in distance". In this paper a "competitive recognition" associative memory model is introduced which simulates the competitive persistence of biological species. Unlike most of the conventional networks, the proposed model takes only the prototype patterns as its equilibrium points, so that the spurious points are effectively excluded. Furthermore, it is shown that, as the competitive parameters vary, the network has a unique stable equilibrium point corresponding to the winner competitive parameter and, in this case, the unique stable equilibrium state can be recalled from any initial key.

20.
Angiology ; 40(1): 11-7, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910141

RESUMO

Six patients with subacute cor pulmonale due to tumor embolization to the lungs were reported from China. Five of the 6 patients suffered from progressive unrelenting dyspnea; 4 had completely normal cardiopulmonary findings on physical examination. Four of the 5 patients who had chest roentgenograms showed diffuse bilateral mottling of the lungs with no evidence of cardiomegaly. At autopsy right ventricular hypertrophy was present in all. The pathologic findings in the lungs consisted of multiple microscopic tumor emboli distributed diffusely in the pulmonary arterioles and/or perivascular lymphatics; the lumen of these vessels was obliterated with or without hyperplastic endarteritis. Although the outcome of this not uncommon clinicopathologic entity is generally fatal, early diagnosis followed by prompt effective therapy for the underlying primary neoplasm has been reported to prolong survival.


Assuntos
Neoplasias Pulmonares/secundário , Células Neoplásicas Circulantes , Doença Cardiopulmonar/etiologia , Adulto , Idoso , Feminino , Humanos , Neoplasias Hepáticas , Pulmão/patologia , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata , Doença Cardiopulmonar/diagnóstico , Neoplasias Gástricas
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