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3.
Sci Rep ; 10(1): 9302, 2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32518259

RESUMEN

Biological entities such as fungi in stored grain evolve and interact with the environment in similar fashions as physical fields. An experiment was conducted to study the behavior of the biological field of fungi in stored grain, as well as the interactions between the biological field of fungi and the physical fields of temperature and moisture. A framework of the biological field is presented to describe biological systems in which multiple biological entities co-exist and interact among themselves and with the surrounding environment. The proposed biological field describes the spatio-temporal distribution of a biological entity and its ability of influencing (or being influenced by) the surrounding biotic and abiotic entities through exchange of energy, matter, and/or information. The strength of a biological field of fungi was quantified as the rate of energy conversion by fungi from grain starch to heat. The experimental data showed that the strength of biological field of fungi in stored grain varied in both space and time, with the maximum field strength of 120-133 W m-3 occurred at the location where the biological field of fungi interacted strongly with the temperature and moisture fields.


Asunto(s)
Aspergillus/fisiología , Grano Comestible/fisiología , Microbiología de Alimentos , Almacenamiento de Alimentos , Ecosistema , Grano Comestible/microbiología , Almacenamiento de Alimentos/instrumentación , Almacenamiento de Alimentos/métodos , Análisis Espacio-Temporal , Temperatura , Triticum/microbiología , Triticum/fisiología
4.
Adv Exp Med Biol ; 1185: 425-430, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31884649

RESUMEN

Previous studies of retinal pigment epithelium (RPE) morphology found cell-level and spatial patterning differences in many quantitative metrics in comparing normal and disease conditions. However, most of these studies examined eyes from deceased animals. Here we sought to compare noninvasively imaged RPE cells from live mice to histopathology. We describe changes to improve noninvasive imaging of RPE in the live mouse. In retinal diseases, there can be invasion by Iba1-positive cells, which can be detected by noninvasive imaging techniques. Here we can detect potential Iba1-positive cells at the level of the RPE noninvasively.


Asunto(s)
Epitelio Pigmentado de la Retina/diagnóstico por imagen , Cicatrización de Heridas , Animales , Ratones , Epitelio Pigmentado de la Retina/patología
6.
Zhonghua Xin Xue Guan Bing Za Zhi ; 46(6): 450-457, 2018 Jun 24.
Artículo en Chino | MEDLINE | ID: mdl-29925181

RESUMEN

Objective: To explore the effect of microRNA-21 (miR-21) on myocardial fibrosis in mice with chronic viral myocarditis (CVMC) and related mechanisms. Methods: Forty 4-week-old Balb/c male mice were randomly divided into 4 groups (n=10 each): phosphate buffer saline (PBS) group, CVMC group, CVMC+miR-21 inhibitor group, CVMC+isotype control group. The first injection of Coxsackie virus B3 (CVB3) or PBS was performed on day 0, and the total study time was 42 days. Each mouse in CVMC group, CVMC+miR-21 inhibitor group and CVMC+isotype control group was intraperitoneally (i.p) injected with 100TCID50 CVB3 0.1, 0.15, and 0.2 ml on day 0, 14, and 28, respectively. The mice in PBS group were i.p injected with the same dose of PBS at the same time point. After the initial infection, each mouse in CVMC+miR-21 inhibitor group and CVMC+isotype control group was intravenously injected with 0.1 ml miR-21 inhibitor or 0.1 ml isotype control, on day 14 and 28. Cardiac function was measured on surviving mice of 4 groups by echocardiography on day 42. Then, the hearts were removed aseptically to observe the expressions of green fluorescence protein (GFP). The myocardial pathological changes were examined with HE, Masson staining and the myocardial pathological scores (PS), the collagen volume fraction (CVF) were calculated respectively. The levels of miR-21, collagen typeⅠ-A1 (COL1-A1) and collagen type Ⅲ-A1 (COL3-A1) mRNA in heart were detected by quantitative real-time polymerase chain reaction (RT-qPCR). Furthermore, the expressions of transforming growth factor-ß1 (TGF-ß1) and mothers against decapentaplegic homolog 7(Smad7) in heart were determined with Western blot assay. Results: (1) Cardiac function in 4 groups: Compared with PBS group, left ventricular end systolic diameter (LVESD) and left ventricular end diastolic diameter (LVEDD) were markedly increased in CVMC group and CVMC+isotype control group (all P<0.05), whereas the left ventricular ejection fraction (LVEF) was decreased (P<0.05). LVESD and LVEDD were significantly decreased, and LVEF was increased in CVMC+miR-21 inhibitor group compared with those in CVMC group and CVMC+isotype control group (all P<0.05). (2) Myocardial pathological changes: The expressions of GFP in CVMC+miR-21 inhibitor group and CVMC+isotype control group were visible in heart tissues frozen sections. The hearts in CVMC group and CVMC+isotype control group were enlarged and stiff, inflammatory cells were visible and significantly increased myocardial fibrosis was evidenced in mice of these two groups. Higher PS and CVF were evidenced in CVMC group (PS: 1.14±0.69 vs. 0, CVF: (17.86±2.61)% vs. (5.70±1.42)%, all P<0.05) and CVMC+isotype control group(PS: 1.00±0.63 vs. 0, CVF: (16.78±2.58)% vs. (5.70±1.42)%, all P<0.05) compared to PBS group. Compared with CVMC group and CVMC+isotype control group, degree of cardiac fibrosis was reduced in mice of CVMC+miR-21 inhibitor group (CVF: (11.01±2.55)% vs. (17.86±2.61)%, (11.01±2.55)% vs. (16.78±2.58)%, all P<0.05), whereas PS were similar between them (PS: 0.89±0.60 vs. 1.14±0.69, 0.89±0.60 vs. 1.00±0.63, all P>0.05). (3) Cardiac expressions of miR-21, COL1-A1 and COL3-A1 mRNA: The cardiac expressions of miR-21, COL1-A1 mRNA, COL3-A1mRNA in CVMC group and CVMC+isotype control group were markedly higher than those in PBS group (all P<0.05), which were significantly downregulated in CVMC+miR-21 inhibitor group (all P<0.05 vs. CVMC group and CVMC+isotype control group). (4) The cardiac expressions of TGF-ß1 and Smad7 protein: The cardiac expressions of TGF-ß1 protein in CVMC group and CVMC+isotype control group were markedly higher, whereas the cardiac Smad7 protein expressions were significantly lower (all P<0.05) than those in PBS group (all P<0.05), these changes could be reversed in CVMC+miR-21 inhibitor group (P<0.05 vs. CVMC group and CVMC+isotype control group). Conclusions: Our results suggest that miR-21 contributes to the myocardial fibrosis in CVMC mice through modulating TGF-ß1/Smad7 signaling pathway.


Asunto(s)
Cardiomiopatías , MicroARNs , Miocarditis , Animales , Cardiomiopatías/metabolismo , Enterovirus Humano B , Fibrosis , Masculino , Ratones , MicroARNs/fisiología , Miocarditis/metabolismo , Miocarditis/virología , Miocardio , Proteína smad7/fisiología , Factor de Crecimiento Transformador beta1/fisiología
7.
Mol Psychiatry ; 21(6): 844-56, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26324101

RESUMEN

Of the two isoforms of Liver X receptor (LXR), LXRß has been shown to have major effects in the central nervous system (CNS) and on the regulation of aquaporins while LXRα has its most marked effects on cholesterol homeostasis. Both receptors have immunomodulatory functions. In LXRαß knockout (ko) mice, the CNS phenotype is much more severe than in the LXRß ko mice, suggesting a contribution of LXRα in CNS functions. One of the most striking abnormalities in the brains of LXRαß ko mice is the occlusion of the lateral ventricles with age. In the present study, we have found by immunohistochemical staining that both LXRα and LXRß are expressed in the cell nuclei of the epithelium of the choroid plexus and in the ependymal cells surrounding the lateral ventricles. The two receptors regulate several genes and can compensate for each other on expression of genes involved in structural integrity (E-cadherin, P-cadherin and ß-catenin) and function (aquaporin 1 and carbonic anhydrase IX). Aquaporin 4 (AQ4) is not expressed in the choroid plexus but is expressed in the astrocytic end feet and ependymal cells. AQP4 expression was increased in white matter around lateral ventricles but not in neurons of LXRαß ko mice. The data show that LXR is a regulator of cerebrospinal fluid (CSF) both at the choroid plexus and at the astrocytic end feet and defects in the synthesis of cerebrospinal fluid may be targeted by LXR agonists to facilitate CSF production, turnover and clearance in CNS diseases.


Asunto(s)
Líquido Cefalorraquídeo/metabolismo , Receptores X del Hígado/metabolismo , Animales , Acuaporina 4/metabolismo , Acuaporinas/metabolismo , Cadherinas/metabolismo , Líquido Cefalorraquídeo/fisiología , Plexo Coroideo , Homeostasis/fisiología , Metabolismo de los Lípidos/genética , Receptores X del Hígado/agonistas , Receptores X del Hígado/genética , Ratones , Ratones Noqueados , Receptores Nucleares Huérfanos/agonistas , Isoformas de Proteínas/metabolismo , beta Catenina/metabolismo
8.
Minerva Pediatr ; 67(6): 489-94, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26530491

RESUMEN

AIM: Intranasal corticosteroids (INS) have been proven effective in controlling postnasal drip, decreasing inflammatory response, reducing nasal swelling, and increasing aeration of the sinuses such that INS are recommended as treatment of sinusitis. METHODS: Fifty children with acute rhinosinusitis, 50 children with acute rhiniosinusitis and allergic rhinitis (AR), and 20 rhiniosinusitis children as control were selected for investigation. Each group had a single-blind treatment of three types: with coamoxiclav only, with coamoxiclav plus INS, and with matched placebo (without antibiotics and INS) for two weeks. Nasal symptoms were then evaluated. The outcome was measured by using major symptom score (MSS) after treatment for 14 days. RESULTS: Therapeutic effectiveness was 92% in rhinosinusitis patients treated with co-amoxiclav and 84% in those treated with co-amoxiclav plus INS. Among patients with sinusitis combined with AR, therapeutic efficacy was 88% for those treated with co-amoxiclav and 96% for those treated with co-amoxiclav plus INS. Only 30% of the symptoms were reduced in the placebo group. CONCLUSION: There are no statistical differences in the acute sinusitis group treated with co-amoxiclav with or without INS. In the sinusitis with AR group, the efficacy of co-amoxiclav with INS is higher than in children treated with co-amoxiclav alone.


Asunto(s)
Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Fluticasona/uso terapéutico , Rinitis/tratamiento farmacológico , Sinusitis/tratamiento farmacológico , Enfermedad Aguda , Administración Intranasal , Adolescente , Combinación Amoxicilina-Clavulanato de Potasio/administración & dosificación , Antialérgicos/administración & dosificación , Antialérgicos/uso terapéutico , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Quimioterapia Combinada , Femenino , Fluticasona/administración & dosificación , Humanos , Masculino , Rinitis Alérgica/tratamiento farmacológico , Método Simple Ciego , Resultado del Tratamiento
9.
Geobiology ; 11(6): 593-601, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24102974

RESUMEN

In this study, iron reduction and concomitant biomineralization of a deep-sea iron reducing bacterium (IRB), Shewanella piezotolerans WP3, were systematically examined at different hydrostatic pressures (0.1, 5, 20, and 50 MPa). Our results indicate that bacterial iron reduction and induced biomineralization are influenced by hydrostatic pressure. Specifically, the iron reduction rate and extent consistently decreases with the increase in hydrostatic pressure. By extrapolation, the iron reduction rate should drop to zero by ~68 MPa, which suggests a possible shut-off of enzymatic iron reduction of WP3 at this pressure. Nano-sized superparamagnetic magnetite minerals are formed under all the experimental pressures; nevertheless, even as magnetite production decreases, the crystallinity and grain size of magnetite minerals increase at higher pressure. These results imply that IRB may play an important role in iron reduction, biomineralization, and biogeochemical cycling in deep-sea environments.


Asunto(s)
Presión Hidrostática , Hierro/metabolismo , Shewanella/metabolismo , China , Microscopía Electrónica de Transmisión , Oxidación-Reducción , Agua de Mar/microbiología , Shewanella/aislamiento & purificación
10.
Behav Genet ; 43(4): 340-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23756614

RESUMEN

We aimed to analyze how genetic and environmental factors account for variations in body mass index (BMI), waist circumference (WC) and their mutual correlation in Chinese children. We measured BMI and WC in 588 pairs of twins (53 % monozygotic twins) aged 8-17 years and applied structural equation modeling to the data. For the younger children (8-12 years of age), heritability estimates of BMI were 0.56 for boys and 0.69 for girls; for the older children (13-17 years of age), the corresponding figures were 0.64 and 0.71, respectively. We observed moderate heritability estimates in WC: the corresponding figures were 0.24 and 0.56 for the younger children, and 0.27 and 0.33 for the older children, respectively. The heterogeneity test for genetic variance of BMI and WC was statistically significant between the two age groups for both sexes (p < 0.001). The proportions of BMI and WC variations due to shared and non-shared environmental factors remained stable during childhood in both sexes. Bivariate genetic analyses showed that genetic correlations between BMI and WC were strong for the younger children (rg = 0.75 for boys, rg = 0.98 for girls) and the older children (rg = 1.0 for both boys and girls). Both sexes showed moderate non-shared environmental correlations in the two age groups, whereas shared environmental correlations--except among male younger children--were not statistically significant. Genetic factors play an important role in variations in BMI and WC during childhood. Common genetic and non-shared environmental factors explained most of the association between BMI and WC for both boys and girls.


Asunto(s)
Composición Corporal/genética , Índice de Masa Corporal , Interacción Gen-Ambiente , Circunferencia de la Cintura/genética , Adolescente , Niño , China , Ambiente , Femenino , Humanos , Masculino , Gemelos Dicigóticos , Gemelos Monocigóticos
11.
J Investig Allergol Clin Immunol ; 21(7): 556-62, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22312941

RESUMEN

BACKGROUND: Atopic diseases, including asthma, allergic rhinitis, and atopic eczema, are major illnesses among children. Recent studies conducted worldwide have shown diverse trends in the prevalence of asthma, with a steady increase detected in industrialized countries. Other studies, however, have revealed a leveling trend or even a declining prevalence. OBJECTIVE: The purpose of this study was to evaluate the current prevalence of allergic conditions in 6-to7-year-old schoolchildren in Taipei, Taiwan, and to analyze time trends. METHODS: We evaluated the prevalence and severity of asthma and other allergic conditions using a phase I International Study of Asthma and Allergies in Childhood core written questionnaire previously administered in Taipei in 1994 and 2002. RESULTS: A total of 24 999 first-grade students from 153 elementary schools completed the questionnaire. The proportion of children with wheeze ever and nocturnal cough in the past 12 months was significantly increased in 2007 compared to 1994 and 2002. No significant differences were detected in the prevalence of current wheeze or physician-diagnosed asthma. The prevalence of severe wheezing symptoms in the past 12 months (> or = 4 attacks of wheeze, > or = 1 night of sleep disturbance due to wheeze per week, wheeze-limiting speech, and exercise-induced wheeze) decreased significantly. The prevalence and severity of rhinitis symptoms increased significantly during the 13-year period analyzed. The prevalence of eczema symptoms-defined as recurrent itchy rash and typical atopic eczema distribution in the past 12 months--also increased. CONCLUSIONS: We observed an increase only in the prevalence and severity of current allergic symptoms in allergic rhinitis and atopic eczema.


Asunto(s)
Hipersensibilidad/epidemiología , Niño , Femenino , Humanos , Masculino , Prevalencia , Índice de Severidad de la Enfermedad , Taiwán/epidemiología , Factores de Tiempo
12.
Braz J Med Biol Res ; 40(7): 979-84, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17653452

RESUMEN

Transitional cell carcinoma (TCC) of the urothelium is often multifocal and subsequent tumors may occur anywhere in the urinary tract after the treatment of a primary carcinoma. Patients initially presenting a bladder cancer are at significant risk of developing metachronous tumors in the upper urinary tract (UUT). We evaluated the prognostic factors of primary invasive bladder cancer that may predict a metachronous UUT TCC after radical cystectomy. The records of 476 patients who underwent radical cystectomy for primary invasive bladder TCC from 1989 to 2001 were reviewed retrospectively. The prognostic factors of UUT TCC were determined by multivariate analysis using the COX proportional hazards regression model. Kaplan-Meier analysis was also used to assess the variable incidence of UUT TCC according to different risk factors. Twenty-two patients (4.6%). developed metachronous UUT TCC. Multiplicity, prostatic urethral involvement by the bladder cancer and the associated carcinoma in situ (CIS) were significant and independent factors affecting the occurrence of metachronous UUT TCC (P = 0.0425, 0.0082, and 0.0006, respectively). These results were supported, to some extent, by analysis of the UUT TCC disease-free rate by the Kaplan-Meier method, whereby patients with prostatic urethral involvement or with associated CIS demonstrated a significantly lower metachronous UUT TCC disease-free rate than patients without prostatic urethral involvement or without associated CIS (log-rank test, P = 0.0116 and 0.0075, respectively). Multiple tumors, prostatic urethral involvement and associated CIS were risk factors for metachronous UUT TCC, a conclusion that may be useful for designing follow-up strategies for primary invasive bladder cancer after radical cystectomy.


Asunto(s)
Carcinoma de Células Transicionales/patología , Neoplasias Primarias Secundarias/patología , Neoplasias de la Vejiga Urinaria/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/cirugía , Cistectomía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Neoplasias de la Vejiga Urinaria/cirugía
13.
Braz. j. med. biol. res ; 40(7): 979-984, July 2007. tab, graf
Artículo en Inglés | LILACS | ID: lil-455999

RESUMEN

Transitional cell carcinoma (TCC) of the urothelium is often multifocal and subsequent tumors may occur anywhere in the urinary tract after the treatment of a primary carcinoma. Patients initially presenting a bladder cancer are at significant risk of developing metachronous tumors in the upper urinary tract (UUT). We evaluated the prognostic factors of primary invasive bladder cancer that may predict a metachronous UUT TCC after radical cystectomy. The records of 476 patients who underwent radical cystectomy for primary invasive bladder TCC from 1989 to 2001 were reviewed retrospectively. The prognostic factors of UUT TCC were determined by multivariate analysis using the COX proportional hazards regression model. Kaplan-Meier analysis was also used to assess the variable incidence of UUT TCC according to different risk factors. Twenty-two patients (4.6 percent). developed metachronous UUT TCC. Multiplicity, prostatic urethral involvement by the bladder cancer and the associated carcinoma in situ (CIS) were significant and independent factors affecting the occurrence of metachronous UUT TCC (P = 0.0425, 0.0082, and 0.0006, respectively). These results were supported, to some extent, by analysis of the UUT TCC disease-free rate by the Kaplan-Meier method, whereby patients with prostatic urethral involvement or with associated CIS demonstrated a significantly lower metachronous UUT TCC disease-free rate than patients without prostatic urethral involvement or without associated CIS (log-rank test, P = 0.0116 and 0.0075, respectively). Multiple tumors, prostatic urethral involvement and associated CIS were risk factors for metachronous UUT TCC, a conclusion that may be useful for designing follow-up strategies for primary invasive bladder cancer after radical cystectomy.


Asunto(s)
Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Transicionales/patología , Neoplasias Primarias Secundarias/patología , Neoplasias de la Vejiga Urinaria/patología , Cistectomía , Carcinoma de Células Transicionales/cirugía , Estudios de Seguimiento , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Neoplasias de la Vejiga Urinaria/cirugía
14.
Biochemistry (Mosc) ; 70(1): 62-8, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15701050

RESUMEN

Interleukin-4 receptors (IL-4Rs) are expressed on a wide variety of human cancer cells, and therefore it may be a good option to treat IL-4R-bearing tumors with IL-4-fusing immunotoxins. In this study, the gene encoding human interleukin-4 mutein cpIL-4(13D) was obtained through overlapping polymerase chain reaction. A chimeric immunotoxin was constructed by genetically fusing the mutein cpIL-4(13D) to a modified version of Pseudomonas exotoxin A (PE38KDEL) and was expressed in Escherichia coli AD494 (DE3). The expression level of the fusion protein was about 30% of the total bacterial protein assessed by SDS-PAGE analysis. After purification by affinity chromatography and anion exchange chromatography, the chimeric protein was tested for its cytotoxicity. Our data show that cpIL-4(13D)-PE38KDEL has improved cytotoxicity on IL-4R-bearing tumor cells in comparison with other IL-4-fusing immunotoxins and might be useful in treating tumors with a large number of IL-4Rs.


Asunto(s)
Inmunotoxinas/química , Inmunotoxinas/farmacología , Receptores de Interleucina-4/química , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/farmacología , Animales , Secuencia de Bases , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/genética , Vectores Genéticos , Glioblastoma/patología , Humanos , Inmunoconjugados , Células L , Ratones , Datos de Secuencia Molecular , Receptores de Interleucina-4/fisiología , Proteínas Recombinantes de Fusión/biosíntesis
15.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 21(9): 649-51, 2001 Sep.
Artículo en Chino | MEDLINE | ID: mdl-12575547

RESUMEN

OBJECTIVE: To observe the effect of Shuangcao Tuihuang Granule-1 (SCTH-1) in treating severe jaundice of acute icterohepatitis and to study its mechanism. METHODS: Thirty-four patients with severe jaundice of acute icterohepatitis were treated with SCTH-1, their therapeutic effects were analyzed. In the experimental studies, the influences of SCTH-1 on acute liver injury, liver superoxide dismutase (SOD) and serum ALT and AST were monitored. RESULTS: The markedly effective rate and effective rate of the treated group were 73.5% and 23.5% respectively. The markedly effective rate of the treated group was obviously higher than that of the control group (P < 0.05). Experimental study revealed that SCTH-1 could reduce the level of serum transaminase and inflammation of liver tissue in mice with acute liver damage. In addition, SCTH-1 could raise the activity of liver SOD (P < 0.05). CONCLUSION: SCTH-1 could accelerate the jaundice subsidence, improve the liver function and ameliorate the liver injury, its mechanism was possibly correlated with raising SOD activity, scavenging the oxygen free radicals.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Colestasis Intrahepática/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Galactosa/análogos & derivados , Hepatitis Viral Humana/tratamiento farmacológico , Fitoterapia , Adolescente , Adulto , Anciano , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Colestasis Intrahepática/etiología , Femenino , Hepatitis Viral Humana/complicaciones , Humanos , Masculino , Ratones , Persona de Mediana Edad
16.
J Microbiol Immunol Infect ; 33(1): 25-8, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10806960

RESUMEN

The serum levels of osteocalcin (OC), a sensitive and specific biochemical marker of bone formation, were measured in 36 asthmatic children before and after intravenous administration of glucocorticoid (GC), methylprednisolone (1 mg/kg/6 h). A statistically significant (p < 0.005) decrease in OC level (13.5-2.7 microg/L) after the completion of 1-day treatment. In patients who received 2-day treatment, the OC levels further declined and reached about 20% of the pretreatment levels. Blood samples collected from patients who received 3-day treatment showed serum OC had declined to an even lower level after the completion of therapy (11.5-1.8 microg/L). An inverse relationship was found between the OC concentration and the duration of GC therapy. GC therapy induced a minor, significant decrease of serum alkaline phosphatase level but did not influence serum calcium level. A tendency toward decrease of serum phosphate level was also noted during GC treatment. An acute effect of GC therapy on the suppression of osteoblasts was biochemically revealed by the finding of reduced serum OC levels. The results suggest that early change in serum OC may be a useful indicator for patients at high risk of bone loss.


Asunto(s)
Asma/tratamiento farmacológico , Metilprednisolona/uso terapéutico , Osteocalcina/sangre , Fosfatasa Alcalina/sangre , Asma/sangre , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Factores de Tiempo
17.
J Bacteriol ; 181(12): 3681-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10368141

RESUMEN

The ClpYQ (HslUV) ATP-dependent protease of Escherichia coli consists of an ATPase subunit closely related to the Clp ATPases and a protease component related to those found in the eukaryotic proteasome. We found that this protease has a substrate specificity overlapping that of the Lon protease, another ATP-dependent protease in which a single subunit contains both the proteolytic active site and the ATPase. Lon is responsible for the degradation of the cell division inhibitor SulA; lon mutants are UV sensitive, due to the stabilization of SulA. lon mutants are also mucoid, due to the stabilization of another Lon substrate, the positive regulator of capsule transcription, RcsA. The overproduction of ClpYQ suppresses both of these phenotypes, and the suppression of UV sensitivity is accompanied by a restoration of the rapid degradation of SulA. Inactivation of the chromosomal copy of clpY or clpQ leads to further stabilization of SulA in a lon mutant but not in lon+ cells. While either lon, lon clpY, or lon clpQ mutants are UV sensitive at low temperatures, at elevated temperatures the lon mutant loses its UV sensitivity, while the double mutants do not. Therefore, the degradation of SulA by ClpYQ at elevated temperatures is sufficient to lead to UV resistance. Thus, a protease with a structure and an active site different from those of Lon is capable of recognizing and degrading two different Lon substrates and appears to act as a backup for Lon under certain conditions.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Endopeptidasa Clp , Endopeptidasas/metabolismo , Proteínas de Escherichia coli , Escherichia coli/enzimología , Escherichia coli/genética , Proteínas de Choque Térmico/metabolismo , Operón , Proteasa La , Serina Endopeptidasas/metabolismo , Proteasas ATP-Dependientes , Adenosina Trifosfatasas/genética , Endopeptidasas/genética , Escherichia coli/efectos de la radiación , Genotipo , Proteínas de Choque Térmico/genética , Fenotipo , Mapeo Restrictivo , Serina Endopeptidasas/genética , Supresión Genética , Rayos Ultravioleta
18.
J Bacteriol ; 177(7): 1834-9, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7896708

RESUMEN

Transcription of the metE gene in Salmonella typhimurium and Escherichia coli is positively regulated by the MetR protein, with homocysteine serving as a coactivator. It was shown previously that MetR binds to and protects from DNase I digestion a 24-bp sequence in the metE metR regulatory region from nucleotides -48 to -71 relative to the metE transcription initiation site (designated as site 1). In this study, we show that purified MetR protein also binds to and protects a second 24-bp sequence adjacent to the original site, from nucleotides -24 to -47 relative to the metE transcription initiation site (designated as site 2). Single and multiple base changes were introduced into sites 1 and 2 in a metE-lacZ fusion. Base pair changes in site 1 or site 2 away from the MetR consensus binding sequence resulted in decreased metE-lacZ expression, suggesting that both sites are necessary for expression. DNase I footprint analysis showed that MetR bound at the high-affinity site 1 enhances MetR binding at the low-affinity site 2. A 2-bp change in site 2 toward the MetR consensus binding sequence resulted in high metE-lacZ expression; the increased expression was MetR dependent but homocysteine independent.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas de Escherichia coli , Genes Bacterianos , Genes Reguladores , Salmonella typhimurium/genética , Transactivadores/metabolismo , Secuencia de Bases , Sitios de Unión , Operón Lac , Metiltransferasas , Datos de Secuencia Molecular , Mutación , Transactivadores/genética
19.
FEMS Microbiol Lett ; 108(2): 145-50, 1993 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8486240

RESUMEN

In Salmonella typhimurium the metE and metR promoters overlap and are divergently transcribed. Three tandem repeats of an 8 bp sequence defined previously as the metE operator site for MetJ-mediated repression also overlap the -35 region of the metR promoter. Starting with a metE-lacZ.metR-galK double gene fusion, site-directed mutagenesis was used to change nucleotides in each of the repeat units from the consensus sequence. Each mutation, along with the wild-type metE-lacZ.metR-galK gene fusion, was cloned into phage lambda gt2. Regulation of the metE and metR genes was examined by measuring beta-galactosidase and galactokinase levels in Escherichia coli strains lysogenized with phage carrying the wild-type and mutant fusions. Mutations in each of the 8 bp repeat units disrupt MetJ-mediated repression for both the metE-lacZ and metR-galK gene fusions, suggesting that the metE and metR genes share a common operator site for the MetJ repressor.


Asunto(s)
5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa , Proteínas Bacterianas/biosíntesis , Proteínas de Escherichia coli , Regiones Operadoras Genéticas/genética , Proteínas Represoras/genética , Salmonella typhimurium/genética , Transactivadores/biosíntesis , Secuencia de Bases , Represión Enzimática/genética , Galactoquinasa/biosíntesis , Galactoquinasa/genética , Regulación Bacteriana de la Expresión Génica , Metiltransferasas , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Proteínas Recombinantes de Fusión/biosíntesis , Secuencias Repetitivas de Ácidos Nucleicos/genética , beta-Galactosidasa/biosíntesis , beta-Galactosidasa/genética
20.
Artículo en Chino | MEDLINE | ID: mdl-8168235

RESUMEN

Two hundred cases of Echinochasmus liliputanus infection were randomly divided into three groups and treated with pyquiton at a single dose of 10.5 and 2.5 mg/kg, respectively. As assessed one month after treatment the egg negativity rates were 100%, 98.7% and 96.5%, respectively. The symptoms such as abdominal pain, distension, diarrhea and anorexia relieved. The results suggest that pyquiton is effective against Echinochasmus liliputanus infection.


Asunto(s)
Praziquantel/administración & dosificación , Infecciones por Trematodos/tratamiento farmacológico , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad
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