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1.
J Chem Phys ; 160(23)2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904943

RESUMEN

We investigated the spectrum of density fluctuations of a liquid crystal, CB7CB, in two different orientations by using high-resolution inelastic x-ray scattering. Our analysis, based on Bayesian principles, revealed that high-frequency collective excitations propagate through this mesoscale-ordered sample in a peculiar manner that lies somewhere between those observed in liquids and crystalline systems. Interestingly, when we probed longer length scales, a more pronounced solid-like response emerged. This was mainly characterized by anomalously sharp inelastic excitations and the onset of shear mode propagation. Comparison with previous x-ray diffraction results suggests a correlation between the observed behavior and the mesogen arrangement.

2.
J Endocrinol Invest ; 47(4): 1029-1036, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37728722

RESUMEN

PURPOSE: Obesity is the main driving factor for comorbidities in Prader-Willi syndrome (PWS) patients due to overeating behaviors. The gut microbiota has been implicated in the etiology of obesity and associated comorbidities. The purpose of the present study was to characterize the fecal microbiota in Chinese patients with PWS and compare it to that of patients with obesity as well as healthy controls. METHODS: We conducted a cross-sectional study with 35 PWS patients (PWS), 35 patients with obesity (OB), and 35 healthy controls (HC). Metagenomic sequencing was performed in stool samples. RESULTS: The composition of the fecal microbiota in PWS patients differed from that of participants in the OB and HC groups. It was characterized by increased Akkermansia Eubacterium, Eubacterium rectale, and Roseburia intestinalis and decreased Parabacteroides and Phascolarctobacterium. Additionally, the homeostatic model assessment of insulin resistance (HOMA-IR) was lower in PWS patients than in patients with obesity. Spearman rank correlation analysis showed that Achromobacter, Acidiphilium, Xylophilus, and Frisingicoccus were significantly negatively correlated with HOMA-IR. CONCLUSION: The composition of the gut microbiota in Chinese PWS patients differed from that in patients with obesity, which might contribute to higher insulin sensitivity in PWS patients.


Asunto(s)
Microbioma Gastrointestinal , Resistencia a la Insulina , Síndrome de Prader-Willi , Niño , Humanos , Estudios Transversales , Obesidad
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 45(7): 706-711, 2022 Jul 12.
Artículo en Zh | MEDLINE | ID: mdl-35768378

RESUMEN

Coronavirus Disease-2019 (COVID-19) has been a major public health issue all over the world, placing a significant burden on available healthcare resources. The most common types of COVID-19 are the mild and common forms. Although the proportion of the severe-critical types is smaller, the rate of death is significantly higher and the medical resources required tend to be greater. Thus, a variety of scores based on other disease and COVID-19 were used to assess the risk of poor prognosis on the COVID-19, including the common scores for community-acquired pneumonia, sepsis and viral pneumonia. Unfortunately, the above scores often lacked an adequate description of the applicable population or were at high risk of bias with unknown applicability. Therefore, the article summarized the existing scores, aiming to provide a reference for clinical prognostic risk assessment.


Asunto(s)
COVID-19 , Neumonía Viral , Humanos , Neumonía Viral/diagnóstico , Neumonía Viral/epidemiología , Pronóstico , Medición de Riesgo , SARS-CoV-2
4.
Zhonghua Jie He He Hu Xi Za Zhi ; 45(3): 276-281, 2022 Mar 12.
Artículo en Zh | MEDLINE | ID: mdl-35279991

RESUMEN

Objective: To better understand the clinical characteristics of pulmonary nocardiosis associated with bronchiectasis. Methods: Patients diagnosed as bronchiectasis complicated with pulmonary nocardiosis in 9 tertiary general hospitals in China were enrolled from March 2016 to March 2020, with the record of general data, imaging performance and pathogen. The literature was reviewed. Results: Totally 17 patients were included. There were 12 females and 5 males. The ages ranged from 45 to 79 years, with an average of (63±9) years. There were 15 nonsmokers and 2 smokers, all of whom with chronic course. The clinical manifestations were mostly cough, expectoration, hemoptysis, fever, and dyspnea. The imaging manifestation was bronchiectasis in both lungs, with the most common involvement in the left lower lung, right middle lobe and left lingual lobe. Sputum cultures were positive in 10 cases, bronchoalveolar lavage fluid (BALF) cultures were positive in 6 cases, and next generation gene sequencings were positive in 4 cases, including 2 cases of Nocardia gelsenkii, 2 cases of Nocardia abscess, 2 cases of Nocardia stellate, 1 case of Nocardia mexicana, 1 case of Nocardia otitis caviae, and 9 cases of undetermined Nocardia. There were 3 cases of Klebsiella pneumoniae, 2 cases of Pseudomonas aeruginosa and 2 cases of Aspergillus. The symptoms and imaging of all patients were improved after anti Nocardia therapy. Conclusions: Bronchiectasis combined with nocardiosis is more common in middle-aged and elderly women without smoking, which is similar to the clinical manifestations of Lady Windermere syndrome. Bronchiectasis often involves the left lower lobe, right middle lobe and left lingual lobe. Nocardia infection might further precipitate the initiation and progression of bronchiectasis.


Asunto(s)
Bronquiectasia , Nocardiosis , Neumonía , Anciano , Bronquiectasia/diagnóstico , Femenino , Hemoptisis/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Nocardiosis/diagnóstico , Esputo
5.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(0): E013, 2020 Feb 15.
Artículo en Zh | MEDLINE | ID: mdl-32061066

RESUMEN

Objective: To summarize and analyze the clinical and imaging characteristics of patients with 2019 novel coronavirus pneumonia in the early stage in Beijing. Methods: A retrospective analysis of clinical and imaging data of 9 patients with 2019 novel coronavirus infection diagnosed in one fever clinicic in Beijing from January 18, 2020 to February 3, 2020. Results: 5 male and 4 female was included in those 9 patients, whose median age was 36 years, and the age range from 15 to 49 years. 8 of these patients had no underlying disease and one suffered from diabetes. 7 patients had a history of travel to Wuhan City or Hubei Province, and one patient was a medical staff. Two family clustered was found. The incubation period was 1 to 6 days. The clinical manifestations were fever in 8 cases (8/9) , dry cough in 5 cases (5/9) , pharyngalgia in 4 cases (4/9) , fatigue in 4 cases (4/9) , body soreness in 4 cases (4/9) , and blocked or watery nose in 1 case (1/9) . Six patients (6/9) had abnormal cell peripheral blood, of which 3 (3/9) had an increased monocyte count, 2 (2/9) had a reduced lymphocyte , and 1 (1/9) had an increased leukocyte count, while the 3 patients had normal cell blood routines. The median of CRP was 16.3 mg/L, including 5 patients with slightly elevated (5/9) , 4 patients with normal values (4/9) . the results of procalcitonin test were negative in5 patients. Three patients were examined by chest X-ray examination, one of which was normal, one case showed infiltrates of right upper lung, and another showed in right lower lung. All patients underwent chest HRCT. And 7 cases (7/9) showed multiple ground glass exudation, including 5 cases (5/7) involved bilateral lungs, 2 cases (2/7) involved unilateral lung, 3 cases (3/7) with patchy consolidation, and 2 cases (2/9) showed no abnormality. Conclusions: The patents with 2019 novel coronavirus pneumonia in this study generally have an epidemiological history. The clinical manifestations are fever and cough. Peripheral white blood cell counts were most normal And PCT were all negative. Chest HRCT manifested as multiple ground-glass opacities with partly consolidation. Some patients had normal chest radiographs but HRCT showed pneumonia. Some patients had no pneumonia on chest HRCT.

6.
Zhonghua Jie He He Hu Xi Za Zhi ; 43(3): 215-218, 2020 Mar 12.
Artículo en Zh | MEDLINE | ID: mdl-32164091

RESUMEN

Objective: To summarize and analyze the clinical and imaging characteristics of patients with 2019 novel coronavirus pneumonia in the early stage in Beijing. Methods: A retrospective analysis of clinical and imaging data of 9 patients with 2019 novel coronavirus infection diagnosed in one fever clinicic in Beijing from January 18, 2020 to February 3, 2020. Results: 5 male and 4 female was included in those 9 patients, whose median age was 36 years, and the age range from 15 to 49 years. 8 of these patients had no underlying disease and one suffered from diabetes. 7 patients had a history of travel to Wuhan City or Hubei Province, and one patient was a medical staff. Two family clustered was found. The incubation period was 1 to 6 days. The clinical manifestations were fever in 8 cases (8/9) , dry cough in 5 cases (5/9) , pharyngalgia in 4 cases (4/9) , fatigue in 4 cases (4/9) , body soreness in 4 cases (4/9) , and blocked or watery nose in 1 case (1/9) . Six patients (6/9) had abnormal cell peripheral blood, of which 3 (3/9) had an increased monocyte count, 2 (2/9) had a reduced lymphocyte, and 1 (1/9) had an increased leukocyte count, while the 3 patients had normal cell blood routines. The median of CRP was 16.3 mg/L, including 5 patients with slightly elevated (5/9) , 4 patients with normal values (4/9) . the results of procalcitonin test were negative in5 patients. Three patients were examined by chest X-ray examination, one of which was normal, one case showed infiltrates of right upper lung, and another showed in right lower lung. All patients underwent chest HRCT. And 7 cases (7/9) showed multiple ground glass exudation, including 5 cases (5/7) involved bilateral lungs, 2 cases (2/7) involved unilateral lung, 3 cases (3/7) with patchy consolidation, and 2 cases (2/9) showed no abnormality. Conclusions: The patents with 2019 novel coronavirus pneumonia in this study generally have an epidemiological history. The clinical manifestations are fever and cough. Peripheral white blood cell counts were most normal And PCT were all negative. Chest HRCT manifested as multiple ground-glass opacities with partly consolidation. Some patients had normal chest radiographs but HRCT showed pneumonia. Some patients had no pneumonia on chest HRCT.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus , Pulmón , Neumonía Viral/diagnóstico por imagen , Adolescente , Adulto , Beijing/epidemiología , Betacoronavirus/aislamiento & purificación , Betacoronavirus/patogenicidad , Biomarcadores , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/transmisión , Tos/etiología , Salud de la Familia , Fatiga/etiología , Femenino , Fiebre/etiología , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neumonía Viral/complicaciones , Neumonía Viral/epidemiología , Neumonía Viral/etiología , Neumonía Viral/transmisión , Radiografía Torácica , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X , Viaje , Adulto Joven
7.
Artículo en Zh | MEDLINE | ID: mdl-29294535

RESUMEN

Objective: To investigate the effect of silica dust on protein oxidative injury in the lung tissue of mice. Methods: A total of 60 mice were randomly divided into control group (not exposed to dust) , 2-hour group (inhalation of dust for 2 hours per day) , 4-hour group (inhalation of dust for 4 hours per day) , and 8-hour group (inhalation of dust for 8 hours per day) , with 15 mice in each group. During dust exposure, the mice were placed in a dust exposure cabinet; the dust was blown with an air blower and the concentration was maintained at 125 mg/m(3). All mice were exposed to silica dust for 3 weeks. The changes of the lung were observed after dust exposure ended, and spectrophotometry was performed to measure the activity of superoxide dismutase (SOD) and the content of malondialdehyde (MDA) and protein carbonyl in the lung tissue. Results: The 2-, 4-, and 8-hour groups had marked edema, sporadic punctate hemorrhage, and nodular shadow in the lungs. Compared with the control group, the 2-, 4-, and 8-hour groups had a significant increase in lung coefficient (7.03±0.78 mg/g, 8.48±0.93 mg/g, and 8.99±0.85 mg/g vs 5.52±0.81 mg/g, P<0.05) . Compared with the control group, the 2-, 4-, and 8-hour groups had significant increases in the content of MDA (2.83±0.52, 3.94±0.65, and 4.56±0.77 nmol/mg prot vs 1.26±0.36 nmol/mg prot, P<0.05) and protein carbonyl (1.61±0.44, 1.96±0.47, and 2.20±0.58 nmol/mg prot vs 1.13±0.21 nmol/mg prot, P<0.05) in lung tissue. The 4- and 8-hour groups had a significantly lower activity of SOD than the control group (153.69±20.58 and 140.35±18.97 U/mg prot vs 186.00±25.46 U/mg prot, P<0.05) . Conclusions: Silica dust may lead to protein oxidative injury in the lung tissue of mice, which might play an important role in lung injury.


Asunto(s)
Polvo , Pulmón/fisiopatología , Dióxido de Silicio/efectos adversos , Animales , Pulmón/metabolismo , Malondialdehído/metabolismo , Ratones , Estrés Oxidativo , Distribución Aleatoria , Espectrofotometría , Superóxido Dismutasa/metabolismo
8.
Phys Rev Lett ; 117(17): 176603, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27824456

RESUMEN

The perovskite SrIrO_{3} is an exotic narrow-band metal owing to a confluence of the strengths of the spin-orbit coupling (SOC) and the electron-electron correlations. It has been proposed that topological and magnetic insulating phases can be achieved by tuning the SOC, Hubbard interactions, and/or lattice symmetry. Here, we report that the substitution of nonmagnetic, isovalent Sn^{4+} for Ir^{4+} in the SrIr_{1-x}Sn_{x}O_{3} perovskites synthesized under high pressure leads to a metal-insulator transition to an antiferromagnetic (AF) phase at T_{N}≥225 K. The continuous change of the cell volume as detected by x-ray diffraction and the λ-shape transition of the specific heat on cooling through T_{N} demonstrate that the metal-insulator transition is of second order. Neutron powder diffraction results indicate that the Sn substitution enlarges an octahedral-site distortion that reduces the SOC relative to the spin-spin exchange interaction and results in the type-G AF spin ordering below T_{N}. Measurement of high-temperature magnetic susceptibility shows the evolution of magnetic coupling in the paramagnetic phase typical of weak itinerant-electron magnetism in the Sn-substituted samples. A reduced structural symmetry in the magnetically ordered phase leads to an electron gap opening at the Brillouin zone boundary below T_{N} in the same way as proposed by Slater.

9.
J Synchrotron Radiat ; 20(Pt 2): 266-71, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23412483

RESUMEN

An X-ray Raman spectrometer for studies of local structures in minerals is discussed. Contrary to widely adopted back-scattering spectrometers using ≤10 keV X-rays, a spectrometer utilizing ~20 keV X-rays and a bent Laue analyzer is proposed. The 20 keV photons penetrate mineral samples much more deeply than 10 keV photons, so that high intensity is obtained owing to an enhancement of the scattering volume. Furthermore, a bent Laue analyzer provides a wide band-pass and a high reflectivity, leading to a much enhanced integrated intensity. A prototype spectrometer has been constructed and performance tests carried out. The oxygen K-edge in SiO(2) glass and crystal (α-quartz) has been measured with energy resolutions of 4 eV (EXAFS mode) and 1.3 eV (XANES mode). Unlike methods previously adopted, it is proposed to determine the pre-edge curve based on a theoretical Compton profile and a Monte Carlo multiple-scattering simulation before extracting EXAFS features. It is shown that the obtained EXAFS features are reproduced fairly well by a cluster model with a minimal set of fitting parameters. The spectrometer and the data processing proposed here are readily applicable to high-pressure studies.

10.
Phys Rev Lett ; 109(4): 046401, 2012 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-23006099

RESUMEN

We have successfully determined the hitherto unknown sign of the B(4)(4) Stevens crystal-field parameter of the tetragonal heavy-fermion compound CeCu(2)Si(2) using vector q-dependent nonresonant inelastic x-ray scattering experiments at the cerium N(4,5) edge. The observed difference between the two different directions, q∥[100] and q∥[110], is due to the anisotropy of the crystal-field ground state in the (001) plane and is observable only because of the utilization of higher than dipole transitions possible in nonresonant inelastic x-ray scattering. This approach allows us to go beyond the specific limitations of dc magnetic susceptibility, inelastic neutron scattering, and soft x-ray spectroscopy, and provides us with a reliable information about the orbital state of the 4f electrons relevant for the quantitative modeling of the quasiparticles and their interactions in heavy-fermion systems.

11.
Phys Rev Lett ; 107(15): 155503, 2011 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-22107300

RESUMEN

We have studied the effects of multiple-wave diffraction in a novel optical scheme recently published by Shvyd'ko et al. utilizing Bragg diffraction of x rays in backscattering geometry from asymmetrically cut crystals for achieving energy resolutions beyond the intrinsic width of the Bragg reflection. By numerical simulations based on dynamic x-ray diffraction and by experimentation involving two-dimensional angular scans of the back-reflecting crystal, multiple-wave diffraction was found to contribute up to several tens percent loss of efficiency but can be avoided without degrading the energy resolution of the original scheme by careful choice of azimuthal orientation of the diffracting crystal surface and by tilting of the crystal perpendicular to the dispersion plane.

12.
J Chem Phys ; 134(18): 184502, 2011 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-21568516

RESUMEN

The THz dynamics of liquid glycerol has been probed by inelastic x-ray scattering at different pressure spanning the 0.66-3 Kbar range. A comparison with ultrasound absorption results available in literature leads us to identify the presence of two different relaxations, a structural (slow) relaxation and a microscopic (fast) one. Although the former has been already thoroughly studied in glycerol by lower frequency spectroscopic techniques, no hints on the latter are so far available in literature. We observe that the characteristic timescale of this fast relaxation ranges in the sub-picosecond, tends to decrease with increasing the wave-vector and seems rather insensitive to pressure changes. Finally, the timescale and strength of the fast relaxation have a direct link revealing the microscopic, single particle, nature of the involved process.

13.
Eur Rev Med Pharmacol Sci ; 25(6): 2481-2492, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33829434

RESUMEN

OBJECTIVE: Burns are one of the most commonly occurring soft tissue injuries worldwide. It has been reported that burns are associated with a higher prevalence of complications, mortality, and hospitalization-related outcomes in patients with coexisting diabetes mellitus. Moreover, the morbidity and mortality related outcomes associated with diabetes in patients with burns. However, since then, several studies reporting the prognostic role of diabetes in patients with burns have been published. Therefore, in this present study, we attempt to develop a current state of evidence evaluating the prognostic influence of diabetes mellitus on infectious complications, duration of hospital stay and mortality-related outcomes in patients with burns. The aim of the study is to determine the overall effect of diabetes mellitus on infectious complications, duration of hospital stay and mortality-related outcomes in patients with burns. MATERIALS AND METHODS: We performed a systematic search of the academic literature in four academic databases including EMBASE, CENTRAL, Scopus, and MEDLINE according to PRISMA guidelines. A random effect meta-analysis was carried out to evaluate the pooled effect size associated with diabetes mellitus on the outcome of infectious complications, duration of hospital stay and mortality in patients with burns. RESULTS: From a total of 1,397 studies, 13 eligible studies with 16,538 patients (3415F, 8361M) with burns were included in the analysis. Among these patients, 1702 patients had diabetes, and 14,836 patients were reported to be non-diabetic. A random effect meta-analysis revealed small-to-large size positive effect of diabetes on the infectious outcome (Hedge's g: 0.2, 95% CI: -0.03 to 0.44), overall mortality (0.16, -0.06 to 0.39), and duration of hospital stay (0.98, 0.50 to 1.45) in patients with burns. CONCLUSIONS: The present systematic review and meta-analysis provides evidence regarding the high morbidity and mortality related outcomes for diabetic patients with burns. The present study confirms the findings of a previously published systematic review suggesting diabetes to be an important and independent risk factor delineating the prognostic outcome of burns.


Asunto(s)
Quemaduras/diagnóstico , Diabetes Mellitus/diagnóstico , Adulto , Femenino , Hospitalización , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad
14.
Zhonghua Wei Chang Wai Ke Za Zhi ; 23(10): 984-989, 2020 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-33053994

RESUMEN

Objective: To investigate the clinical value of carbon nanoparticles zonal tracer technique in lymph node retrieval of gastric cancer (GC). Methods: A retrospective cohort study was carried out. Clinicopathological data of GC patients who underwent radical D2 resection with carbon nanoparticles tracer in The First Affiliated Hospital of Hainan Medical University and Hainan Cancer Hospital from December 2015 and February 2019 were collected. Those with postoperative pathology of T1-2, Borrmann IV type GC, distant metastasis, preoperative neoadjuvant chemotherapy and incomplete data were excluded. A total of 181 patients were enrolled in this study, including 113 cases from the First Affiliated Hospital of Hainan Medical University and 68 cases from Hainan Cancer Hospital. Patients were categorized into two groups based on the methods of carbon nanoparticles tracer: zonal tracer group and traditional tracer group. In the traditional tracer group, 0.1-0.3 ml of carbon nanoparticle was injected subserously at the upper, lower, left and right 4 injection points 0.5 cm away from the edge of the tumor in the normal serous membrane. In the zonal tracer group, on the basis of the traditional tracer group, 0.1-0.3 ml of carbon nanoparticle was injected subserously at the first branch of the suprapyloric right gastric artery into the stomach, the first branch of the subpyloric right gastroepiploic artery into the stomach, the first branch of the minor curvature left gastric artery into the stomach and the first branch of the greater curvature left gastroepiploic artery into the stomach, respectively. The display of lymphatic vessels in each location and lymph nodes in each group by the tracing method was observed. The number of black-stained lymph nodes, the black staining rate of lymph nodes, the total number of detected lymph nodes, the total number of positive lymph nodes, and the metastatic rate of lymph node were compared between the two groups. Results: Eighty-nine patients were assigned to zonal tracer group, and 92 patients to traditional tracer group. There were no significant differences in baseline information between the two groups (all P>0.05). The median number of black-stained lymph nodes (median: 25.0 vs. 13.5, Z=-7.158, P<0.001) and the black staining rate of lymph nodes [(70.8±12.0)% vs. (47.1±15.7)%, t=11.399, P<0.001) in the zonal tracer group were significantly higher than those in the traditional tracer group. The total detected number of lymph nodes (37.5±11.5 vs. 29.6±11.8, t=4.581, P<0.001) and the total number of negative lymph nodes (31.3±12.5 vs. 24.9±11.1, t=3.621, P<0.001) were significantly higher in the zonal tracer group than those in the traditional tracer group. There were no significant differences in the total number of positive lymph nodes (median: 4.0 vs. 3.0, Z=-1.485, P=0.137), lymph node metastatic rate [78.7% (70/89) vs. 72.8% (67/92), χ(2)=0.834, P=0.361] and metastatic degree [median: 11% vs. 10%, Z=-0.483, P=0.629] between the two groups. Conclusion: The carbon nanoparticles zonal tracer method can increase the black-staining rate of lymph nodes and the detected number of lymph nodes, thus improving the accuracy of gastric cancer staging.


Asunto(s)
Nanopartículas , Neoplasias Gástricas , Materiales Biocompatibles , Carbono , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos , Metástasis Linfática , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía
15.
Neuroscience ; 158(4): 1577-88, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19110040

RESUMEN

Activation of muscarinic acetylcholine receptors (mAChRs) inhibits spinal nociceptive transmission by potentiation of GABAergic tone through M(2), M(3), and M(4) subtypes. To study the signaling mechanisms involved in this unique mAChR action, GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) of lamina II neurons were recorded using whole-cell patch clamp techniques in rat spinal cord slices. The mAChR agonist oxotremorine-M caused a profound increase in the frequency of GABAergic sIPSCs, which was abolished in the Ca(2+)-free solution. Inhibition of voltage-gated Ca(2+) channels with Cd(2+) and Ni(2+) largely reduced the effect of oxotremorine-M on sIPSCs. Blocking nonselective cation channels (NSCCs) with SKF96365 or 2-APB also largely attenuated the effect of oxotremorine-M. However, the KCNQ channel blocker XE991 and the adenylyl cyclase inhibitor MDL12330A had no significant effect on oxotremorine-M-induced increases in sIPSCs. Furthermore, the phosphoinositide-3-kinase (PI3K) inhibitor wortmannin or LY294002 significantly reduced the potentiating effect of oxotremorine-M on sIPSCs. In the spinal cord in which the M(3) subtype was specifically knocked down by intrathecal small interfering RNA (siRNA) treatment, SKF96365 and wortmannin still significantly attenuated the effect of oxotremorine-M. In contrast, SKF96365 and wortmannin both failed to alter the effect of oxotremorine-M on sIPSCs when the M(2)/M(4) mAChRs were blocked. Therefore, our study provides new evidence that activation of mAChRs increases synaptic GABA release through Ca(2+) influx and voltage-gated Ca(2+) channels. The PI3K-NSCC signaling cascade is primarily involved in the excitation of GABAergic interneurons by the M(2)/M(4) mAChRs in the spinal dorsal horn.


Asunto(s)
Potenciales Postsinápticos Inhibidores/fisiología , Neuronas/fisiología , Receptores Muscarínicos/fisiología , Transducción de Señal/fisiología , Médula Espinal/citología , Ácido gamma-Aminobutírico/metabolismo , Animales , Antracenos/farmacología , Biofisica , Cadmio/farmacología , Calcio/metabolismo , Interacciones Farmacológicas , Estimulación Eléctrica/métodos , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Técnicas In Vitro , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Activación del Canal Iónico/efectos de los fármacos , Activación del Canal Iónico/fisiología , Masculino , Agonistas Muscarínicos/farmacología , Inhibición Neural/efectos de los fármacos , Inhibición Neural/fisiología , Neuronas/efectos de los fármacos , Níquel/farmacología , Oxotremorina/análogos & derivados , Oxotremorina/farmacología , Técnicas de Placa-Clamp/métodos , Bloqueadores de los Canales de Potasio/farmacología , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Ratas , Ratas Sprague-Dawley , Receptores Muscarínicos/clasificación , Receptores Muscarínicos/genética , Transducción de Señal/efectos de los fármacos
16.
Arterioscler Thromb Vasc Biol ; 25(3): 611-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15653565

RESUMEN

OBJECTIVE: Ethnicity-based research may identify new clues to the pathogenesis of atherosclerotic disease. Therefore, we sought to determine whether carotid lesions differ between 20 Chinese and 20 Caucasian Americans by MRI. METHODS AND RESULTS: Inclusion criteria were >50% stenosis as measured by duplex ultrasound and recent symptoms attributed to carotid artery disease. The patients were imaged in 2 centers (Beijing, China and Seattle, Wash) using a standardized protocol. Both carotid arteries were reviewed quantitatively (lumen, wall, outer wall, tissue components) and morphologically (lesion types, fibrous cap status). Significant differences between the Chinese and Americans were found for the mean size of the lipid/necrotic core (13.6 versus 7.8 mm2; P=0.002), percentage of slices with calcified type VII lesions (1.6 versus 12.4%; P=0.03), and percentage of slices with early type III lesions (19.3 versus 9.3%; P=0.02). Furthermore, the mean outer wall area in the common carotid artery was larger in the Chinese population (P=0.007). CONCLUSIONS: This pilot study suggests that composition and morphology of atherosclerotic lesions in symptomatic carotid disease differ between ethno-racial groups. Quantitative MRI-based review of carotid atherosclerosis comparing plaque morphology and composition between ethno-racial groups is feasible, and future MRI studies may improve our understanding of the pathophysiology of this disease.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Enfermedades de las Arterias Carótidas/etnología , Enfermedades de las Arterias Carótidas/patología , Imagen por Resonancia Magnética , Población Blanca/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Arteria Carótida Común/patología , China/epidemiología , Femenino , Humanos , Imagen por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Fantasmas de Imagen , Proyectos Piloto , Reproducibilidad de los Resultados , Factores de Riesgo , Estados Unidos/epidemiología
17.
Int J Radiat Biol ; 62(6): 719-27, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1362765

RESUMEN

To investigate the effect of exposure to tobacco smoke (TS) on the development of irradiation-induced pneumonitis in rats, five groups of animals were investigated including controls (C), tobacco smoke exposed (S), irradiated (RNS) and irradiated and tobacco smoke exposed (RS). An additional group (RS/NS) was exposed to tobacco before irradiation but not afterwards. Rats were exposed to diluted mainstream cigarette smoke at a concentration of about 0.4 mg/l in a nose-only exposure system for 1/day, 5 days/week for 10 weeks. Exposure to TS started 3 weeks before irradiation in which the basal one-third of both lungs was exposed to a single dose of 28 Gy. In previous studies this dose had been shown to cause significant pneumonitis. All the animals were killed at 7 weeks after irradiation. Examination of the morphology of lung sections showed less pulmonary inflammation in the RS group than in the RNS group. This was also reflected in the results of bronchoalveolar lavage (BAL) which showed a decline in cell recovery and a marked decrease in the numbers of mast cells and neutrophils in the RS rats compared with the RNS animals. The concentration of hyaluronan in lavage fluid was increased in the RNS and RS/NS group while no increase was found in the RS group. A marked increase in BAL protein was also seen in the RNS and RS/NS groups as compared with the RS group but all were significantly higher than in unirradiated controls. This indicates that smoking suppresses the radiation-induced inflammation but to a lesser degree affects the radiation-induced increase in membrane permeability as reflected by increased protein levels in BAL. Moreover, the marked effects on the numbers of mast cells and neutrophils in the RS group may indicate that these cells play an important role in the mechanism by which tobacco smoke modulates the effects of irradiation. When exposure to tobacco smoke was terminated immediately after irradiation (RS/NS), the inflammatory response was unaffected.


Asunto(s)
Pulmón/patología , Neumonía/etiología , Traumatismos Experimentales por Radiación/complicaciones , Contaminación por Humo de Tabaco , Animales , Líquido del Lavado Bronquioalveolar/citología , Masculino , Neumonía/patología , Ratas , Ratas Sprague-Dawley
18.
Ann Clin Lab Sci ; 25(6): 493-503, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8572558

RESUMEN

To understand the development of cadmium (Cd)-induced renal tubular dysfunction, cross-sectional assessment of renal function in the inhabitants of the Cd-polluted Jinzu River basin in Toyama, Japan, was carried out. Sixty-seven men and 78 women, aged 56 to 71 years whose urinary beta 2-microglobulin (beta 2-m) exceeded 1,000 micrograms/g creatinine, were examined and divided into five groups according to their values of fractional excretion of beta 2-m (FE beta 2-m). Comparisons were made between six groups including the inhabitants of a non-polluted area as a reference group. Significantly increased values of fractional excretion of urate (FEUA), calcium (FECa), sodium (FENa), and chloride (FECl), serum creatinine and beta 2-m, and urinary protein were detected even in the subjects with FE beta 2-m level below 1 percent compared with the reference group. Fractional phosphate reabsorption (percent TRP) was significantly decreased in the subjects with FE beta 2-m level above 10 percent. Creatinine clearance (CCr) decreased with increase in FE beta 2-m, and the subjects with FE beta 2-m above 30 percent showed significantly decreased CCr values compared to those with FE beta 2-m below 30 percent. In summary, FEUA, FECa, FENa, and FECl, as well as low-molecular-weight proteins such as beta 2-m, are increased in the early stage of Cd-induced renal tubular dysfunction. Although percent TRP was maintained by the decreased CCr, there was a marked decrease in percent TRP in subjects with progressive stage showing FE beta 2-m level above 10 percent. No sex difference in renal tubular dysfunction was found in this cross-sectional study.


Asunto(s)
Intoxicación por Cadmio/fisiopatología , Enfermedades Renales/inducido químicamente , Riñón/fisiopatología , Contaminantes Químicos del Agua/envenenamiento , Anciano , Calcio/orina , Cloruros/orina , Creatinina/sangre , Femenino , Humanos , Concentración de Iones de Hidrógeno , Japón , Enfermedades Renales/fisiopatología , Masculino , Persona de Mediana Edad , Proteinuria/orina , Sodio/orina , Ácido Úrico/orina , Microglobulina beta-2/metabolismo , Microglobulina beta-2/orina
19.
Chin Med J (Engl) ; 106(5): 357-60, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8404278

RESUMEN

The computed tomographic (CT) images of 52 patients of small peripheral lung nodule < 3 cm proved pathologically were reviewed. Air bronchogram (AB) was found in 14 nodules on thin-section CT images, in which well or moderately differentiated small adenocarcinomas were only seen with lipidic growth. Squamous-cell, large-cell carcinomas and small benign lung nodules had no AB sign both on CT image and in pathologic specimens.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/diagnóstico por imagen , Adenocarcinoma/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Broncografía , Carcinoma de Células Escamosas/diagnóstico por imagen , Diagnóstico Diferencial , Humanos , Neumorradiografía , Tomografía Computarizada por Rayos X
20.
Zhongguo Yi Liao Qi Xie Za Zhi ; 25(2): 88-90, 2001 Mar.
Artículo en Zh | MEDLINE | ID: mdl-12583148

RESUMEN

A simulated experimental system on humoral integrated parameter tests controlled by a microcomputer is developed for overcoming hard training in maintenance technical skill. This paper describes its structure, characteristics, functions and the prospects of its applications.


Asunto(s)
Autoanálisis/instrumentación , Análisis de los Gases de la Sangre/instrumentación , Líquidos Corporales/química , Colorimetría/instrumentación , Simulación por Computador , Microcomputadores , Diseño de Equipo , Humanos , Diseño de Software
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