Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Sci Rep ; 13(1): 21196, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040917

RESUMO

Einstein-Podolsky-Rosen (EPR) steering is a quantum effect based on quantum entanglement and it is the key resource for building quantum networks because of its useful properties. Based on the criterion for genuine multipartite EPR steering, the genuine quadripartite EPR steering is confirmed and it can be generated by a spontaneous parametric down-conversion cascaded process with two sum-frequency generations in an optical superlattice. This occurs either below the oscillation threshold and without oscillation threshold. The influence of the parameters of cascaded nonlinear process on the quadripartite EPR steering among signal, idler, and two sum-frequency beams are also discussed. Choosing appropriate nonlinear parameters can achieve good quadripartite quantum steering. This scheme of the generation of genuine quadripartite EPR steering has potential applications in quantum communication and computing.

2.
Opt Express ; 28(3): 2722-2731, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32121954

RESUMO

Recently, Einstein-Podolski-Rosen (EPR) steering has important application in quantum information processing, and it has been received considerable attention because of its uniqueness. The properties of quantum steering among three output fields generated by cascaded nonlinear processes of quasi-phase-matching third-harmonic generation in an optical cavity are investigated. Based on the criteria for multipartite EPR steering which proposed by He and Reid [PRL, 111, 250403 (2013)], the genuine tripartite EPR steering among pump, second-harmonic, and third-harmonic is demonstrated. The parameters which affect the quantum property are also discussed.

4.
J Dairy Sci ; 102(6): 5182-5190, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30904299

RESUMO

The objective of current study was to investigate the effect of N-acetyl-l-methionine (NALM) supplementation on lactation performance and plasma variables in mid-lactating dairy cows. Forty-eight multiparous cows were blocked into 12 groups based on parity, days in milk, and milk production and were randomly assigned to 1 of the 4 treatments: 0, 15, 30, or 60 g/d of NALM per cow to supplement the basal diet. The experiment was conducted over a 13-wk period, with the first week as adaptation. The yields of milk, fat-corrected milk, and milk lactose were increased quadratically, and energy-corrected milk yield tended to increase with increased NALM supplementation in a quadratic manner. The dry matter intake, milk protein yield, milk fat yield, contents of milk composition (protein, fat, lactose, total solids, and milk urea nitrogen), feed efficiency, and body weight change were not affected by NALM supplementation. In addition, plasma methionine concentration was increased quadratically, and proline, total nonessential AA, and total AA concentrations were significantly higher in the 30 g/d group compared with that of the control group. However, other AA and total essential AA concentrations were not affected with supplementation of NALM. Adding NALM increased concentrations of total protein and globulin in plasma, but decreased plasma urea nitrogen concentration in a quadratic manner. Meanwhile, plasma malonaldehyde concentration decreased linearly as doses of NALM addition increased. Our results suggested that the supplementation of NALM improved milk yield and protein synthesis in the liver, and lowered lipid peroxidation in mid-lactating dairy cows.


Assuntos
Bovinos/sangue , Dieta/veterinária , Suplementos Nutricionais , Lactação/efeitos dos fármacos , Metionina/análogos & derivados , Ração Animal/análise , Animais , Feminino , Metionina/metabolismo , Metionina/farmacologia , Leite/metabolismo , Proteínas do Leite/metabolismo , Paridade , Gravidez , Distribuição Aleatória , Ureia/metabolismo
5.
J Dairy Sci ; 101(12): 10985-10990, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30268601

RESUMO

The present study was conducted to investigate the effect of N-carbamoylglutamate (NCG) on milk production and composition in mid-lactating Holstein dairy cows. Sixty multiparous cows with a mean body weight of 669 kg (standard deviation = 71) and 176 days in milk (standard deviation = 55) were blocked based on parity and milk production and randomly assigned into 4 treatments, a basal diet supplemented with 0, 10, 20, or 40 g of NCG/d per cow. Milk yield and composition were recorded weekly, whereas dry matter intake and plasma variables were determined every 2 wk. The results showed that the addition of NCG had no effect on the dry matter intake and milk yield of the cows. Milk fat content and yield increased linearly with NCG addition. The contents of milk protein and total solid also increased linearly in the cows fed NCG, whereas the yield of protein was not affected by the treatments. Conversely, dietary addition of NCG increased the plasma nitric oxide content in a quadratic manner. Moreover, addition of NCG linearly increased the plasma Arg content. Overall, the results indicate that dietary NCG addition increased the milk protein and fat contents, which improved the milk quality of lactating dairy cows.


Assuntos
Ração Animal , Bovinos , Suplementos Nutricionais , Glutamatos/farmacologia , Leite/química , Animais , Indústria de Laticínios/métodos , Dieta/veterinária , Feminino , Lactação , Proteínas do Leite/análise , Paridade , Distribuição Aleatória
6.
J Nanosci Nanotechnol ; 11(11): 9415-20, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413221

RESUMO

We presented our investigations on the absorption and emission properties of the nanocrystalline ZnO particles of different particle sizes (2 nm-5 nm) by sol-gel method. In the room temperature PL spectra, three emission bands, ultraviolet (UV), blue and green were observed. With increasing the particle sizes, both the UV and the visible emission bands shifted to lower energies progressively. From the size-dependency, there was a linear relationship between the energetic maxima of the UV and the green emission bands with a slope of about 0.26, which indicated that the green luminescence of ZnO was produced by the transitions of electrons from deep level to the valence band (or shallow acceptor level). A linear dependence was also found between the energetic maxima of the UV and the blue emissions with a slope of 0.15, the origin this blue emission band is not clear at present. While in van Dijken et al.'s paper, however, they identified only two emission bands in the emission spectra, an UV and a broad visible emission band, and the linear fit between the energetic maxima of these two bands in particles of different sizes has a slope of 0.6, so they proposed that the visible emission in ZnO was originated from the recombination of a shallowly trapped electron with a deeply trapped hole. We attributed this divergence to the fact that the broad visible band is actually composed of two separate emission bands originated from two different recombination processes, and should not had been treated as one emission band.

7.
Neuroscience ; 133(1): 1-15, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15893627

RESUMO

Cognitive deficits persist in patients who survive traumatic brain injury (TBI). Lateral fluid percussion brain injury in the mouse, a model of human TBI, results in hippocampal-dependent cognitive impairment, similar to retrograde amnesia often associated with TBI. To identify potential substrates of the cognitive impairment, we evaluated regional neuronal loss, regional hippocampal excitability and inhibitory synaptic transmission. Design-based stereology demonstrated an approximate 40% loss of neurons through all subregions of the hippocampus following injury compared with sham. Input/output curves recorded in slices of injured brain demonstrated increased net synaptic efficacy in the dentate gyrus in concert with decreased net synaptic efficacy and excitatory postsynaptic potential-spike relationship in area CA1 compared with sham slices. Pharmacological agents modulating inhibitory transmission partially restored regional injury-induced alterations in net synaptic efficacy. Both evoked and spontaneous miniature inhibitory postsynaptic currents (mIPSCs) recorded in surviving dentate granule neurons were smaller and less frequent in injured brains than in uninjured brains. Conversely, both evoked and spontaneous mIPSCs recorded in surviving area CA1 pyramidal neurons were larger in injured brains than in uninjured brains. Together, these alterations suggest that regional hippocampal function is altered in the injured brain. This study demonstrates for the first time that brain injury selectively disrupts hippocampal function by causing uniform neuronal loss, inhibitory synaptic dysfunction, and regional, but opposing, shifts in circuit excitability. These changes may contribute to the cognitive impairments that result from brain injury.


Assuntos
Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Hipocampo/fisiopatologia , Rede Nervosa/fisiologia , Vias Aferentes/fisiologia , Animais , Lesões Encefálicas/patologia , Transtornos Cognitivos/patologia , Giro Denteado/fisiopatologia , Eletrofisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Medo/fisiologia , Hipocampo/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Rede Nervosa/citologia , Técnicas de Patch-Clamp , Sinapses/fisiologia
8.
Life Sci ; 69(22): 2653-62, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11712668

RESUMO

The possible involvement of dopamine D2 and D3 receptors in the action of dopamine (DA) on inhibiting dorsomedial arcuate nucleus (dmARN) neurons in brain slices was determined in this study. Fresh brain slices were prepared from ovariectomized, estrogen-primed Sprague-Dawley rats and used for extracellular single-unit recording. The dmARN neurons were first identified by their inhibitory responses to DA and then tested with PHNO and/or PD128907, selective D2 and D3 agonists, respectively. PD128907 in 5-50 nmole doses significantly inhibited the majority of DA-responsive dmARN neurons (86.3% of 44 units). Moreover, PHNO in 5-25 nmole doses inhibited all DA-responsive neurons tested (100% of 34 units). The inhibitory effects of PHNO and PD128907 were not only prominent; but also persisted in low Ca2+, high Mg2+ medium, indicating that they were acting directly on the recorded neuron. Pretreatment of either raclopride or U99194A, D2 and D3 receptor antagonists respectively, reversed the effects of DA in a few trials. In contrast, SKF81297, a D1 receptor agonist, induced variable responses in dmARN neurons. These results clearly indicate that DA may act through D2 and/or D3 receptors to exhibit an inhibitory effect on presumed TIDA neurons in dmARN.


Assuntos
Agonistas de Dopamina/farmacologia , Neurônios/efeitos dos fármacos , Receptores de Dopamina D2/metabolismo , Animais , Núcleo Arqueado do Hipotálamo/citologia , Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Benzazepinas/farmacologia , Benzopiranos/farmacologia , Encéfalo/citologia , Encéfalo/efeitos dos fármacos , Dopamina/farmacologia , Interações Medicamentosas , Estrogênios/farmacologia , Feminino , Técnicas In Vitro , Núcleo Mediodorsal do Tálamo/citologia , Núcleo Mediodorsal do Tálamo/efeitos dos fármacos , Neurônios/metabolismo , Oxazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D3
9.
Exp Anim ; 50(4): 341-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11515099

RESUMO

The relationship between cryptorchidism and testicular tumors has been well established in canines, and the tumor has been proposed as a model for studying its human counterparts. Herein we report canine malignant retroperitoneal seminoma in a 4-year-old castrated Basset hound, most likely without testicular involvement, similar to that of the classic seminoma of humans.


Assuntos
Criptorquidismo/complicações , Criptorquidismo/veterinária , Neoplasias Renais/patologia , Neoplasias Retroperitoneais/patologia , Seminoma/patologia , Animais , Cães , Masculino , Invasividade Neoplásica , Orquiectomia
10.
J Acquir Immune Defic Syndr ; 26(4): 365-70, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11317080

RESUMO

Guangxi Province, China recently experienced an outbreak of HIV-1 infection among heroin users. We studied HIV-1 incidence rates and associated risk factors for HIV-1 infection among heroin users residing in Pingxiang City. A total of 318 heroin users were followed from February 1998 through January 1999 (median follow-up: 8.1 months). Of these, 130 were prospectively followed from January through September 1999 (median follow-up: 8.3 months). HIV-1 and hepatitis C virus (HCV) incidence rates for each period were calculated. A generalized estimating equation approach was implemented to identify independent risk factors associated with HIV-1 infection across both periods. Among 318 study participants, 97.2% were men. The median age was 22 years. Approximately 60% reported sharing needles. HIV-1 prevalence at baseline was 15.4%. During the first follow-up period, HIV-1 incidence was 2.38 per 100 person years (py), and HCV incidence was 26.8 per 100 py. During the second follow-up period, HIV-1 incidence was 6.86 per 100 py, and HCV incidence was 28.9 per 100 py. After controlling for age and other factors, HCV seropositivity, history of sexually transmitted diseases, and sharing needles were independently associated with HIV-1 infection. These data suggest that HIV-1 incidence was rising over time in Pingxiang City, Guangxi Province. The high incidence of HCV heightens the importance of enhanced prevention programs to reduce injection and needle sharing among heroin users.


Assuntos
Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Dependência de Heroína/virologia , Adulto , Fatores Etários , China/epidemiologia , Suscetibilidade a Doenças , Educação , Feminino , Infecções por HIV/complicações , Infecções por HIV/virologia , Soropositividade para HIV/complicações , Soropositividade para HIV/epidemiologia , Soropositividade para HIV/virologia , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Hepatite C/epidemiologia , Hepatite C/virologia , Dependência de Heroína/complicações , Humanos , Incidência , Masculino , Estado Civil , Uso Comum de Agulhas e Seringas , Prevalência , Fatores de Risco , Fatores Sexuais , Infecções Sexualmente Transmissíveis/complicações , Infecções Sexualmente Transmissíveis/virologia
11.
J Vet Diagn Invest ; 13(2): 167-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11289216

RESUMO

A 7-month-old cat was examined for progressive abdominal distension. Radiography showed a fluid-containing cyst, which had subsequently ruptured as the result of a fall. Nephrectomy was performed, and examination revealed the coexistence of pyelocaliceal diverticula with a cystic intracapsular angiomyolipoma (mesenchymal hamartoma) in the left kidney. The diverticula were present on both cranial and caudal poles of the kidney and were lined by transitional epithelium. The hamartoma was characterized by the presence of multiple mesenchymal tissues, including thick-walled blood vessels, smooth muscle, and adipose tissue.


Assuntos
Angiomiolipoma/veterinária , Doenças do Gato/diagnóstico , Divertículo/veterinária , Neoplasias Renais/veterinária , Angiomiolipoma/complicações , Angiomiolipoma/diagnóstico , Animais , Doenças do Gato/patologia , Doenças do Gato/cirurgia , Gatos , Diagnóstico Diferencial , Divertículo/complicações , Divertículo/diagnóstico , Feminino , Nefropatias/complicações , Nefropatias/diagnóstico , Nefropatias/veterinária , Neoplasias Renais/complicações , Neoplasias Renais/diagnóstico
12.
Brain Res Bull ; 52(6): 567-72, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10974498

RESUMO

Whether the tuberoinfundibular dopaminergic (TIDA) neurons resided in the dorsomedial arcuate nucleus (dmARN) can respond to dopamine and a dopamine D(3) receptor agonist, 7-hydroxydipropylaminotetralin (7-OH-DPAT), was the focus of this study. In studies using extracellular single-unit recording of dmARN neurons in brain slices obtained from ovariectomized rats, dopamine and 7-OH-DPAT inhibited 60.1% (n = 141) and 80.9% (n = 47) of recorded dmARN neurons, respectively. Other dopamine D(1) or D(2) receptor agonists were not as effective. Intracerebroventricular injection of 7-OH-DPAT (10(-9) mol/3 microl) in ovariectomized, estrogen-primed rats significantly lowered the TIDA neuronal activity as determined by 3, 4-dihydroxyphenylacetic acid (DOPAC) levels in the median eminence. Co-administration of a putative D(3) receptor antagonist, U-99194A, could prevent the effect of 7-OH-DPAT. Unilateral microinjection of 7-OH-DPAT or dopamine itself (10(-11)-10(-9) mol/0.2 microl) into the right dmARN exhibited the same inhibitory effect on TIDA neurons. In all, dopamine may act on D(3) receptors to exhibit an inhibitory effect on its own release from the TIDA neurons.


Assuntos
Núcleo Arqueado do Hipotálamo/efeitos dos fármacos , Agonistas de Dopamina/farmacologia , Dopamina/metabolismo , Dopamina/farmacologia , Neurônios/efeitos dos fármacos , Receptores de Dopamina D2/efeitos dos fármacos , Tetra-Hidronaftalenos/farmacologia , Animais , Núcleo Arqueado do Hipotálamo/citologia , Núcleo Arqueado do Hipotálamo/metabolismo , Feminino , Sistema Hipotálamo-Hipofisário/citologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3 , Túber Cinéreo/citologia , Túber Cinéreo/efeitos dos fármacos , Túber Cinéreo/metabolismo
13.
Neuroendocrinology ; 72(1): 11-9, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10940734

RESUMO

The central serotonergic system has long been known to have a stimulatory role on the secretion of prolactin (PRL). The integrity of serotonergic neurotransmission is essential for the expression of the estrogen-induced afternoon PRL surge. Whether its effect on PRL involves change in the activity of tuberoinfundibular dopaminergic (TIDA) neurons has not been ascertained. In adult ovariectomized rats treated with estrogen, depletion of central serotonin (5-HT) by 5,7-dihydroxytryptamine (5,7-DHT, 200 microg/rat, i.c.v.) effectively prevented the afternoon fall in TIDA neuronal activity (using the levels of 3,4-dihydroxyphenylalanine and 3, 4-dihydroxyphenylacetic acid (DOPAC), and the ratio of DOPAC/dopamine in the median eminence as indices), and blunted the afternoon PRL surge. A single injection of a 5-HT(2A) receptor antagonist, ketanserin (5 mg/kg, i.p. at 12.00 h), also had the same effects on the diurnal changes in TIDA neuronal activity and PRL secretion as the treatment with 5,7-DHT did. Intracerebroventricular injection of a 5-HT(2) receptor agonist 2, 5-dimethoxy-4-iodoamphetamine (DOI) in the morning inhibited the TIDA neuronal activity and stimulated PRL secretion in a dose-dependent manner; while injection of a 5-HT(1) agonist, 8-hydroxy-dipropylaminotetralin, was without effect. Injection of DOI in 5,7-DHT-pretreated rats at 14.30 h also lowered the TIDA neuronal activity and reinstated the PRL surge. In all, endogenous 5-HT, acting through the 5-HT(2A) receptor, appears to exhibit an inhibitory effect on TIDA neuronal activity during the afternoon, which is essential for the PRL surge.


Assuntos
Ritmo Circadiano/fisiologia , Dopamina/metabolismo , Hipófise/metabolismo , Prolactina/metabolismo , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , 5,7-Di-Hidroxitriptamina/toxicidade , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Anfetaminas/farmacologia , Animais , Ritmo Circadiano/efeitos dos fármacos , Di-Hidroxifenilalanina/metabolismo , Estrogênios/farmacologia , Feminino , Ketanserina/farmacologia , Degeneração Neural/induzido quimicamente , Degeneração Neural/metabolismo , Neurônios/metabolismo , Ovariectomia , Hipófise/citologia , Prolactina/sangue , Ratos , Ratos Sprague-Dawley , Receptor 5-HT2A de Serotonina , Serotoninérgicos/toxicidade , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia
14.
J Am Anim Hosp Assoc ; 35(3): 200-7, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10333257

RESUMO

Twenty-eight dogs with iatrogenic hyperadrenocorticism were studied. The most common clinical signs were cutaneous lesions (27/28), polydipsia (21/28), polyuria (19/28), and lethargy (16/28). The most predominant findings on biochemical profile were elevated alkaline phosphatase (ALP, 15/28) and alanine transferase (ALT, 14/28); hypercholesterolemia (14/28); elevated aspartate transferase (AST, 12/28); and elevated triglycerides (12/18). Baseline cortisol levels of all 28 dogs were at the lower end of the reference range and exhibited suppressed or no response to adrenocorticotropic hormone (ACTH) stimulation. The mean time for each dog to show initial improvement of clinical signs after corticosteroid withdrawal was six weeks, with another mean time of 12 weeks to demonstrate complete remission.


Assuntos
Corticosteroides/efeitos adversos , Hiperfunção Adrenocortical/veterinária , Doenças do Cão/induzido quimicamente , Doença Iatrogênica/veterinária , Córtex Suprarrenal/efeitos dos fármacos , Córtex Suprarrenal/fisiopatologia , Hiperfunção Adrenocortical/induzido quimicamente , Hormônio Adrenocorticotrópico , Animais , Diagnóstico Diferencial , Doenças do Cão/fisiopatologia , Cães , Feminino , Masculino
15.
J Cancer Res Clin Oncol ; 124(5): 259-64, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9645456

RESUMO

Recently, the expression of fibroblast growth factor 3 (FGF3) was found in 55% of human Kaposi's sarcoma (KS) tumor tissues examined, while almost no expression of FGF3 was found in normal skin. To further these studies, human FGF3 cDNA were constructed by the overlap-extension method. The proteins translated from two FGF3 cDNA, which differ only in the sequences preceding the AUG presumed to be the initiation codon, were shown to have the same molecular mass. This result suggests that translation of human FGF3, which is different from mouse FGF3, begins only at the AUG site. The human FGF cDNA was transfected into NIH3T3 cells. The NIH 3T3 cells transformed by FGF3 were then injected subcutaneously into athymic nude mice. Nodular lesions developed at the injection sites in all seven mice injected with the F3-1 cell clone, which showed high expression of FGF3, and in two out of six mice injected with the F3-2 cell clone, which expressed a low level of FGF3. Histopathological features of these tumors contained fascicles of spindle-shaped cells surrounding irregular endothelial lined vascular clefts, similar to those observed in human KS lesions. Immunohistochemical staining for factor V111 antigen revealed reactivity in multiple areas, especially in abundant vascular structures of the tumor sections examined. The expression of FGF3 together with the FGF receptors FGFR1, FGFR2, and FGFR3, was detected in the mouse tumors by Northern blot analysis. Our results indicate that tumors induced by FGF3-transformed NIH3T3 cells show some similarities to human KS tumors. In conclusion, our results demonstrate the potential tumorigenic and angiogenic role of human FGF3.


Assuntos
Fatores de Crescimento de Fibroblastos/biossíntese , Neovascularização Patológica , Proteínas Proto-Oncogênicas/biossíntese , Receptores de Fatores de Crescimento de Fibroblastos/biossíntese , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/patologia , Animais , Northern Blotting , Testes de Carcinogenicidade , Fator 3 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas/genética , Receptores de Fatores de Crescimento de Fibroblastos/genética , Sarcoma de Kaposi/irrigação sanguínea , Sarcoma de Kaposi/metabolismo , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/metabolismo , Células Tumorais Cultivadas
16.
Zhonghua Jie He He Hu Xi Za Zhi ; 17(3): 168-70, 191, 1994 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-7530604

RESUMO

In this report, We present 4 patients with pulmonary melioidosis. The literatures on epidemiology, clinical manifestation, roentogenology, diagnosis and therapeutics of melioidosis are reviewed.


Assuntos
Burkholderia pseudomallei/isolamento & purificação , Pneumopatias/microbiologia , Melioidose/microbiologia , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
17.
J Cell Physiol ; 145(2): 295-302, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2174064

RESUMO

Changes in intracellular ionized free calcium ([Ca]i), inositol triphosphate (IP3), and sn-1,2-diacylglycerol (DAG) were determined in relation to agonist-induced human neutrophil superoxide (O2-) production. With 0.1 microM N-formyl-methionyl-leucyl-phenylalanine (fMLP) stimulation, generation of IP3 and a peak rise in [Cai] occurred at 30 sec, preceding maximal O2- production (1.5 min) and the maximal rise in DAG mass (4 min). FMLP-induced O2- production was inhibited by pertussis toxin. In cytochalasin B-primed, concanavalin A (Con A) stimulated neutrophils, a peak rise in [Ca]i but not IP3 proceeded O2- production, and pertussis toxin did not inhibit O2- production. EGTA inhibited the cytochalasin B/fMLP-induced increment in [Ca]i and O2- production by 75% and 50%, respectively, and completely ablated the response to cytochalasin B/Con A, suggesting a role for extracellular as well as intracellular calcium in the respiratory burst. However, three types of experiments indicate that an increase in [Ca]i is neither sufficient nor always required for O2- production. First, treatment with ionomycin resulted in a marked increase in [Ca]i but did not cause O2- production. Second, pertussis toxin inhibited both fMLP-induced IP3 generation and O2- production but did not inhibit the rise in [Ca]i. Third, following neutrophil priming with dioctanoylglycerol (diC8), maximal O2- production occurred in response to 0.015 microM fMLP or Con A without a rise in [Ca]i, and diC8/fMLP-induced O2- production was not inhibited by EGTA. Taken together, these data suggest that 1) an increment in [Ca]i is not strictly essential for neutrophil O2- production, 2) unlike fMLP, Con A-induced O2- production does not proceed through a pathway involving the pertussis toxin-sensitive G protein, and 3) regulation of neutrophil [Ca]i involves mechanisms independent of IP3 concentration.


Assuntos
Cálcio/sangue , Concanavalina A/farmacologia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/metabolismo , Superóxidos/sangue , Alcaloides/farmacologia , Diglicerídeos/sangue , Ácido Egtázico , Proteínas de Ligação ao GTP/efeitos dos fármacos , Humanos , Fosfatos de Inositol/sangue , Toxina Pertussis , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Estaurosporina , Fatores de Virulência de Bordetella/farmacologia
18.
Zhonghua Fang She Xue Za Zhi ; 23(3): 146-8, 1989 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-2582904

RESUMO

A clinico-radiologic analysis of 15 cases with exogenous allergic alveolitis in pigeon breeders was reported. There were 4 male and 11 female. The age ranged from 15-68 years, averaging 33.5 years. All cases had history of intimate contact with pigeons. The clinical manifestations were dry cough, dyspnea and Velcro's rales at the base of the lung. The X-ray appearances included increased, coarsened, tortuous and hazy lung markings, reticular shadows, ground glass appearance due to decreased lung lucency, patchy shadows and honeycombed areas of lucency etc. These findings however were nonspecific, and must be differentiated from other diseases. Therefore X-ray signs must be closely correlated with clinical picture before making the diagnosis.


Assuntos
Alveolite Alérgica Extrínseca/diagnóstico por imagem , Pulmão do Criador de Aves/diagnóstico por imagem , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia
19.
Exp Hematol ; 15(1): 65-71, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3780890

RESUMO

Acute disseminated intravascular coagulation (DIC) is a life-threatening condition that may be encountered in many situations, especially in cases of shock with uncontrollable hemorrhage. Anisodamine, an alkaloid extracted from a Chinese herb, is well known for its dramatic therapeutic effect on DIC. Sixty male rabbits were used to establish an acute DIC model. A total of 240 blood samples were taken for laboratory assays of changes in blood coagulation factors, platelet count, platelet adhesion, platelet aggregation, malondialdehyde (MDA), thromboxane B2 (TXB2), and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha). Changes of the microcirculatory status and the rate of the blood flow in the conjunctival capillaries of 60 rabbits were observed with WXS-II microcirculation microscope. Pathological sections of the lungs and kidneys were studied. Our investigation showed the presence of microthrombi in the microvasculature. After treatment with anisodamine, the prothrombin time stayed in the normal range, fibrinogen consumption was lessened, adenosine-diphosphate-induced platelet aggregation was inhibited, thromboxane B2 and malondialdehyde concentrations were significantly lower than in the control group, and the elevated quantity of 6-keto-PGF1 alpha was spared. We concluded that the anti-platelet-aggregating, microcirculation-facilitating, thromboxane-B2-inhibiting, malondialdehyde-inhibiting, and 6-keto-PGF1 alpha-sparing effects of anisodamine are the important mechanisms of its dramatic therapeutic effect on DIC.


Assuntos
Coagulação Intravascular Disseminada/tratamento farmacológico , Alcaloides de Solanáceas/uso terapêutico , 6-Cetoprostaglandina F1 alfa/sangue , Animais , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Intravascular Disseminada/sangue , Coagulação Intravascular Disseminada/patologia , Rim/patologia , Pulmão/patologia , Masculino , Malondialdeído/sangue , Microcirculação/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas/efeitos dos fármacos , Coelhos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Alcaloides de Solanáceas/farmacologia , Tromboxano B2/sangue
20.
Sci Sin B ; 28(12): 1299-310, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3837325

RESUMO

A new physiologic model for dynamic process of Creatine Kinase (CK) after acute myocardial infarction is proposed. The fundamental hypotheses are tested. The new model is better than the log-normal model in goodness of fit. With this new model, the infarct size of complicated cases with double or multiple peak CK curve can be estimated as well as that of uncomplicated cases. To estimate parameters, a nomographic algorithm and a computer program have been designed. In most cases, the initial values for parameters estimated with Marquardt's method can be determined from individual CK data.


Assuntos
Creatina Quinase/sangue , Modelos Cardiovasculares , Infarto do Miocárdio/enzimologia , Humanos , Infarto do Miocárdio/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA