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1.
Geophys Res Lett ; 49(3): e2021GL096069, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35859568

RESUMO

Water storage plays an important role in mitigating heat and flooding in urban areas. Assessment of the water storage capacity of cities remains challenging due to the inherent heterogeneity of the urban surface. Traditionally, effective storage has been estimated from runoff. Here, we present a novel approach to estimate effective water storage capacity from recession rates of observed evaporation during precipitation-free periods. We test this approach for cities at neighborhood scale with eddy-covariance based latent heat flux observations from 14 contrasting sites with different local climate zones, vegetation cover and characteristics, and climates. Based on analysis of 583 drydowns, we find storage capacities to vary between 1.3 and 28.4 mm, corresponding to e-folding timescales of 1.8-20.1 days. This makes the urban storage capacity at least five times smaller than all the observed values for natural ecosystems, reflecting an evaporation regime characterized by extreme water limitation.

2.
Artigo em Zh | MEDLINE | ID: mdl-32746565

RESUMO

Objective: To investigate the effect of perfluorooctane sulfonate (PFOS) on inflammatory factors in human placental trophoblast (HTR-8/Svneo) cells. Methods: HTR-8/Svneo cells were exposed to different concentrations of PFOS (0, 0.01, 0.1, 1.0 mg/L) for 24 h, and the cell survival rates were measured by CCK8. Secretion levels of interleukin-6 (IL-6) , tumor necrosis factor-alpha (TNF-α) and interleukin-10 (IL-10) were detected by ELISA. The mRNA expressions of IL-6, TNF-α and IL-10 were detected by fluorescence quantitative PCR. One-way ANOVA was used to analyse the expressions of inflammatory factors. Results: Compared with the control group, the survival rates of 0.1 and 1.0 mg/L PFOS groups were significantly decreased (P<0.05) . Compared with the control group, the secretion levels of IL-6 were decreased in the 0.01, 0.1 and 1.0 mg/L PFOS groups (P<0.05) , the concentrations of TNF-α were increased in the 0.01 and 1.0 mg/L PFOS groups (P<0.05) , and the concentrations of IL-10 were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) . Compared with the control group, the expressions of IL-6 mRNA were increased in the 0.1 and 1.0 mg/L PFOS groups (P<0.05) , and the expressions of IL-10 mRNA were decreased in the 0.01 mg/L, 0.1 mg/L and 1.0 mg/L PFOS groups (P<0.05) . Conclusion: PFOS can induce changes in the secretion levels of inflammatory cytokines in HTR-8/Svneo cells, resulting in decreased activity of placental trophoblast cells and abnomal placental function.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Fluorocarbonos/toxicidade , Placenta/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , Feminino , Humanos , Gravidez , Testes de Toxicidade , Fator de Necrose Tumoral alfa/genética
3.
Mikrobiol Z ; 78(5): 2-11, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30141858

RESUMO

The red yeasts are currently widely discussed and controversial group of yeasts because of the growing number of reports of their ability to become opportunistic pathogens of plants, animals and humans. The aim of this work was complex identifcation of the red yeast culture isolated from gastrointestinal tract of healthy Hucul long-liver from the Carpathians highland region of Ukraine. Torularhodin was found to be a major component within yeast culture carotenoids complex. According to conventional biochemical and morphological approaches as well as to molecular biological investigation of internal transcribed spacer region (ITS) of ribosomal operon it was concluded that isolate belonged to species Rhodotorula mucilaginosa.


Assuntos
Trato Gastrointestinal/microbiologia , Rhodotorula/classificação , Rhodotorula/isolamento & purificação , Carotenoides/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Humanos , Ucrânia
4.
Intern Med J ; 45(4): 428-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25533739

RESUMO

BACKGROUND: Albuminuria is associated with increased risk of multiple adverse health outcomes, such as progressive renal failure, cardiovascular disease and death. However, in the general population, it is uncertain whether albuminuria is associated with elevated heart rate, which is an independent and powerful risk factor for cardiovascular disease. AIM: To investigate whether an elevated heart rate is an independent factor associated with albuminuria in the general adult population of Korea. METHODS: A cross-sectional analysis was carried out on 5198 Korean adults aged 19 years or older who participated in the fifth (2011) Korea National Health and Nutrition Examination Survey (KNHANES V-2). RESULTS: The prevalence of albuminuria showed an increasing trend throughout the whole range of heart rate, even after adjusting for confounders (P = 0.002). The increment was most profound at the heart rate of 70-75 and >76 beats per minute (b.p.m.; P = 0.011). In multiple logistic regression analysis, age (P < 0.001), hypertension (P < 0.001), diabetes (P < 0.001), hypertriglyceridaemia (P = 0.025), estimated glomerular filtration rate (P = 0.028) and heart rate (P = 0.023) were independently associated with the presence of albuminuria in Korean adults. Compared with participants with heart rate ≤ 64 b.p.m., the odds ratio (95% CI) for albuminuria was 1.50 (1.15-1.96) for those with heart rate ≥ 76 b.p.m. CONCLUSIONS: The prevalence of albuminuria is independently associated with heart rate in the general adult population of Korea.


Assuntos
Albuminúria/diagnóstico , Albuminúria/epidemiologia , Frequência Cardíaca , Inquéritos Nutricionais , Vigilância da População , Adulto , Idoso , Estudos Transversais , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais/tendências , República da Coreia/epidemiologia , Adulto Jovem
5.
J Eur Acad Dermatol Venereol ; 27(5): 609-16, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22404745

RESUMO

BACKGROUND: Vitiligo is an acquired pigmentary disorder caused by the destruction of melanocytes. Two of the major theories regarding the pathogenesis of vitiligo are the autoimmune theory and autocytotoxicity theory, but, the precise pathogenetic mechanism is still not clarified. OBJECTIVES: We investigated the effects of ET-1, tacrolimus and tumour necrosis factor-α (TNF-α) on proliferation and migration of cultured normal human melanocytes (NHMs). We also sought to clarify the theoretical rationale underlying the topical tacrolimus monotherapy or tacrolimus-UV combination therapy as tools for vitiligo treatment. METHODS: The effects of ET-1, tacrolimus and TNF-α on proliferation/migration of cultured NHMs were investigated by MTT assay/Boyden chamber transwell migration assay. We also examined roles of CXC-chemokine receptor II (CXCR II) and matrix metalloproteinases (MMPs) in such conditions. RESULTS: ET-1 exerted a stimulatory effect on melanocyte proliferation and migration, but, tacrolimus exerted a stimulatory effect only on melanocyte migration higher than ET-1. TNF-α inhibited melanocyte proliferation in a dose-dependent manner. Paradoxically, TNF-α-pretreated NHMs exhibited an enhanced proliferative efficiency after being switched to ET-1. We found CXCRII was highly expressed in TNF-α-incubated melanocytes than the agents-free control, and ET-1 treatment after TNF-α preincubation showed the higher levels of CXCRII expression than the condition incubated with TNF-α alone. Moreover, the greater activities of MMP-2 and MMP-9 induced by tacrolimus than ET-1, reflected tacrolimus would enhance migration stimulatory effect in cultured NHMs. CONCLUSIONS: Topical tacrolimus can be used an effective agent for vitiligo treatment as monotherapy, maybe due to its migration stimulatory action or TNF-α inhibitory property, and also as a component in combination therapy with UV treatment, considering the more upregulated MMPs activities are induced and the more effective migrations are feasible by itself than ET-1.


Assuntos
Proliferação de Células/efeitos dos fármacos , Endotelina-1/fisiologia , Imunossupressores/farmacologia , Melanócitos/efeitos dos fármacos , Fototerapia , Tacrolimo/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Vitiligo/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/uso terapêutico , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Receptores CXCR/metabolismo , Tacrolimo/administração & dosagem , Tacrolimo/uso terapêutico
6.
Horm Metab Res ; 43(1): 48-54, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20865648

RESUMO

Patients with hypopituitarism have the feature of metabolic syndrome, including central obesity, insulin resistance, and dyslipidemia. Because metabolic syndrome, including insulin resistance, is the main pathogenesis of the development of nonalcoholic fatty liver disease (NAFLD), we considered that patients diagnosed with hypopituitarism have an increased risk of developing NAFLD. We compared control subjects and hypopituitary men in metabolic parameters and the frequency of fatty liver on abdominal ultrasonography, and analyzed associating factors with the severity of the fatty liver in patients with hypopituitarism. 34 male patients with hypopituitarism and 40 age and sex-matched control subjects were included. The frequency of fatty liver on abdominal ultrasonography was significantly higher in hypopituitary men compared to control subjects (32.5% vs. 70.6%, p=0.001). Ln CRP and free fatty acids were significantly elevated in hypopituitary patients with fatty liver compared to patients without fatty liver. Ln GH was significantly lower in hypopituitary patients with fatty liver. The severity of fatty liver on abdominal ultrasonography correlated with negatively Ln GH, after adjusting for the BMI effect (p=0.020). There is a difference only between the severe fatty liver group and normal liver group in the analysis of the mean Ln GH level between 4 groups according to the severity of fatty liver (p=0.036). In conclusion, NAFLD is more common in hypopituitary patients than control subject. Severe growth hormone deficiency in hypopituitarism was associated with the severe degree of hepatic steatosis in NAFLD.


Assuntos
Hipopituitarismo/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Hormônio do Crescimento/metabolismo , Humanos , Hipopituitarismo/complicações , Hipopituitarismo/diagnóstico por imagem , Metabolismo dos Lipídeos , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Ultrassonografia
7.
Horm Metab Res ; 43(13): 956-61, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22072433

RESUMO

Administration of recombinant human growth hormone (rhGH) in obesity has been known to lead to a decrease in visceral adiposity and an increase in lean body mass. Most studies have used supraphysiological doses of rhGH, which were administered daily or every other day. We aimed to evaluate whether weekly administered low dose of sustained-release rhGH (SR-rhGH) could play a therapeutic role in the treatment of abdominal obesity. Prospective, single-arm, open-label, multicenter pilot study was carried out. Participants were 26 adults aged 40-65 years old with abdominal obesity (male: waist circumference >90 cm, female: waist circumference >85 cm). The subjects were given 3 mg of SR-rhGH, administered subcutaneously, weekly for 26 weeks. SR-rhGH treatment for 26 weeks increased the IGF-1 level by 56.53±76.09 µg/l (SDS 0.77±1.12) compared to the baseline (p=0.0022). After 26 weeks, SR-rhGH treatment reduced abdominal visceral adipose tissue (VAT) (140.35±75.97 to 128.43±73.85 cm2, p=0.0038). Average waist circumference decreased from 96.25±6.41 to 91.93±6.13 cm (p<0.0001) after treatment. However, body weight or lean body mass did not show any significant change. In conclusion, SR-rhGH treatment for 26 weeks reduced abdominal visceral fat and waist circumference without severe adverse events. Further studies may be considered on the role of weekly administered SR-rhGH as a treatment for abdominal obesity.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Hormônio do Crescimento Humano/administração & dosagem , Gordura Intra-Abdominal/metabolismo , Obesidade Abdominal/tratamento farmacológico , Circunferência da Cintura/efeitos dos fármacos , Adulto , Idoso , Preparações de Ação Retardada/efeitos adversos , Esquema de Medicação , Feminino , Hormônio do Crescimento Humano/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Abdominal/metabolismo , Obesidade Abdominal/fisiopatologia , Estudos Prospectivos
8.
Osteoporos Int ; 21(5): 847-53, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19633881

RESUMO

UNLABELLED: Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a serious side effect of bisphosphonate therapy. The incidence of BRONJ is known to be low among patients treated with oral bisphosphonates. We investigated the prevalence, demographics, clinical manifestations, and treatment outcome of 24 patients with oral BRONJ in Asian populations. INTRODUCTION: The long-term safety of oral bisphosphonates is clinically important considering the rare but potentially serious complications such as bisphosphonate-related osteonecrosis of the jaw (BRONJ) versus the effect of reducing and preventing osteoporotic fracture. The incidence of BRONJ is known to be low among patients treated with oral bisphosphonates around the world. However, the prevalence in those taking oral bisphosphonates for osteoporosis in Asian populations is unknown. Moreover, a recent article, showing that the majority of reported patients who received alendronate were Asian American, raised concern about the prevalence of oral BRONJ in Asian populations. The objective of this study was to investigate the estimated prevalence, clinical characteristics, and treatment outcome of oral BRONJ in Asian populations. METHODS: From October 2005 to December 2008, a retrospective review of medical charts identified 24 patients receiving oral bisphosphonates diagnosed as BRONJ at the Department of Oral and Maxillofacial Surgery, Yonsei University Dental Hospital, Seoul, South Korea. RESULTS: The estimated prevalence of oral BRONJ was 0.05-0.07%. The average oral bisphosphonate treatment duration was 43.1 months (range, 5-120 months). Treatment with oral antibiotics and/or surgery including sequestrectomy or alveolectomy showed relatively favorable results. CONCLUSIONS: The prevalence of oral BRONJ in Korea is similar to that reported previously in Western populations. We suggest that recognition of BRONJ and appropriate management pre- and post-dental surgery might reduce the frequency of BRONJ among patients receiving oral bisphosphonates.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Doenças Maxilomandibulares/induzido quimicamente , Osteonecrose/induzido quimicamente , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Doenças Maxilomandibulares/diagnóstico por imagem , Doenças Maxilomandibulares/terapia , Masculino , Pessoa de Meia-Idade , Osteonecrose/diagnóstico por imagem , Osteonecrose/terapia , Osteoporose/tratamento farmacológico , Radiografia Panorâmica , Estudos Retrospectivos , Resultado do Tratamento
9.
J Appl Microbiol ; 109(2): 415-430, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20092541

RESUMO

AIMS: This work has examined the effects of a polycyclic aromatic hydrocarbon and selected toxic metals on fungal populations in a soil microcosm. METHODS AND RESULTS: By using fungal ribosomal intergenic spacer analysis (F-RISA) in combination with real-time PCR quantification, four fungi (D63P2-1, D63C2-1, D21Cu1-1 and D63Pb2-2) with specific primer pairs to each were successfully evaluated for their potential as bioindicators in response to pyrene, copper (Cu) and lead (Pb), supplied singly and in combination. CONCLUSIONS: F-RISA coupled with real-time PCR is a useful approach for the identification of microorganisms with potential as bioindicators of organic and toxic metal contamination. SIGNIFICANCE AND IMPACT OF THE STUDY: These bioindicators could be monitored for their population changes that may indicate pollutant-induced perturbations in a given system.


Assuntos
Monitoramento Ambiental/métodos , Fungos/efeitos dos fármacos , Metais/farmacologia , Pirenos/farmacologia , Microbiologia do Solo , Poluentes do Solo/farmacologia , Cobre/farmacologia , DNA Espaçador Ribossômico/química , Fungos/classificação , Fungos/genética , Chumbo/farmacologia , Metais/análise , Reação em Cadeia da Polimerase , Pirenos/análise , Análise de Sequência de DNA , Poluentes do Solo/análise
10.
J Appl Microbiol ; 108(6): 2030-40, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19922595

RESUMO

AIMS: This study aimed to isolate and identify potential polycyclic aromatic hydrocarbon (PAH)-degrading and/or metal-tolerant fungi from PAH-contaminated and metal-contaminated soils. METHODS AND RESULTS: Pyrene-degrading fungi were isolated from contaminated soil and tested for metal (Cu, Zn and Pb) compound solubilization and metal accumulation. Three strains of Fusarium solani and one of Hypocrea lixii were able to degrade more than 60% of initial supplied pyrene (100 mg l(-1)) after 2 weeks. The isolates were grown on toxic metal (Cu, Pb and Zn)-containing media: all isolates accumulated Cu in their mycelia to values ranging from c. 5.9 to 10.4 mmol per kg dry weight biomass. The isolates were also able to accumulate Zn (c. 3.7-7.2 mmol per kg dry weight biomass) from zinc phosphate-amended media. None of the isolates accumulated Pb. CONCLUSIONS: These fungal isolates appear to show promise for use in bioremediation of pyrene or related xenobiotics and removal of copper and zinc from wastes contaminated singly or in combination with these substances. SIGNIFICANCE AND IMPACT OF THE STUDY: Microbial responses to mixed organic and inorganic pollution are seldom considered: this research highlights the abilities of certain fungal strains to interact with both xenobiotics and toxic metals and is relevant to other studies on natural attenuation and bioremediation of polluted sites.


Assuntos
Cobre/metabolismo , Fusarium/metabolismo , Hypocrea/metabolismo , Pirenos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Zinco/metabolismo , Biodegradação Ambiental , Fusarium/isolamento & purificação , Gasolina , Hypocrea/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Solo/análise
11.
J Appl Microbiol ; 108(3): 985-997, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19761462

RESUMO

AIMS: For identification of members of the fungal order Eurotiales, an 18S rRNA gene-based oligonucleotide microarray was developed and optimized. METHODS AND RESULTS: Eurotiales-specific probes covering most members of the Eurotiales as well as species-specific probes were designed and evaluated with three pure cultures (two fungi from the Eurotiales and one fungus from the Hypocreales). Nearly complete 18S rRNA genes of each reference culture were amplified and fluorescently labelled by random priming. CONCLUSIONS: Positive and negative hybridization results confirmed that the Eurotiales probes tested in this study could correctly identify members of the Eurotiales. The species-specific probes were also capable of species-level detection. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings demonstrate the potential applications of a phylogenetic oligonucleotide microarray approach to characterizing fungal species and populations in environmental and other samples.


Assuntos
Eurotiales/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Ribossômico 18S/genética , Eurotiales/classificação , RNA Fúngico/genética , Especificidade da Espécie
12.
Sci Rep ; 7(1): 6146, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28733577

RESUMO

For recent years, devices that generate non-thermal plasma (NTP) have been introduced into the field of dermatology. Since NTP has demonstrated strong anti-pathogenic activity with safety of use, NTP was first applied to sterilize the skin surface to aid in the healing of various kinds of skin diseases. However, the effect of NTP on skin regeneration has not yet been fully explored. In this study, the effect of NTP on the growth of keratinocytes was tested using the HaCaT human keratinocyte cell line and HRM2 hairless mice. Treatment with NTP allowed confluent keratinocytes to escape from G1 cell cycle arrest and increased the proportion of cells in S and G2 phases. In particular, NTP treatment immediately dispersed E-cadherin-mediated cell-to-cell interactions, resulting in the translocation of ß-catenin to the nucleus and leading to the enhanced transcription of target genes including c-MYC and cyclin D1. Moreover, repeated treatment of the mice with NTP also stimulated epidermal expansion by activating ß-catenin in the epidermal cells. The symptoms of cellular DNA damage were not detected after NTP treatment. Taken together, these results demonstrate that NTP may be employed as a new type of skin regenerating device.


Assuntos
Queratinócitos/metabolismo , Gases em Plasma/administração & dosagem , Regeneração/efeitos dos fármacos , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Antígenos CD/metabolismo , Caderinas/metabolismo , Ciclo Celular , Linhagem Celular , Núcleo Celular/metabolismo , Modelos Animais de Doenças , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Masculino , Camundongos , Gases em Plasma/farmacologia , Cicatrização/efeitos dos fármacos
13.
J Pharm Biomed Anal ; 37(2): 405-10, 2005 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-15708686

RESUMO

This report describes an automated coupled column microbore-high-performance liquid chromatography (HPLC) with fluorescence detection for direct determination of verapamil in small volume of rat plasma. We used HPLC system consisting of three columns such as precolumn, intermediate and analytical column and six-port switching valve and injected small volume of rat plasma to the system without sample preparation. An aliquot of sample was directly injected into Capcell Pak MF Ph precolumn for clean-up and enrichment, 35 mm Capcell Pak C18, intermediate column for concentration of compounds and 250 mm Capcell Pak C18 analytical column for separation of compounds and two mobile phases are used as mobile phase A (50mM ammonium phosphate, pH 4.5) and B (50mM ammonium phosphate:acetonitrile=70:30 v/v). Analysis of verapamil and internal standard, propranolol was performed with direct injection of 10 microl of rat plasma to the system and were eluted at 22 and 12 min, respectively, at a mobile phase flow rate of 0.5 (mobile phase A) and 0.15 ml/min (mobile phase B). The peaks of verapamil and internal standard were good shapes and well separated from any interfering endogenous peaks during a total run time of 25 min. The calibration curve for verapamil showed good linearity (r(2)=0.9997) over the concentration range of 0.01-2.50 microg/ml. The mean RSD (%) values of intra-day (n=5) and inter-day (n=5) variability of verapamil ranged from 1.96 to 9.06 and 0.62 to 3.08%, respectively. The LOD and LOQ were 0.01 and 0.025 microg/ml, respectively, for verapamil using 10 microl of rat plasma. An automated coupled column microbore-HPLC method was successfully applied to a pharmacokinetic study after intravenous injection of 3mg/kg of verapamil to the normal and dimethylnitrosamine (DMN)-induced hepatofibrotic rats.


Assuntos
Verapamil/sangue , Animais , Disponibilidade Biológica , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Modelos Animais de Doenças , Injeções Intravenosas , Cirrose Hepática/sangue , Masculino , Ratos , Ratos Sprague-Dawley
14.
FEBS Lett ; 382(1-2): 179-82, 1996 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-8612746

RESUMO

Incubation of an NADPH-dependent succinic semi-aldehyde reductase from bovine brain with o-phthalaldehyde resulted in a time-dependent loss of enzyme activity. The inactivation followed pseudo first-order kinetics with the second-order rate constant of 28 M(-1) s(-1). The inactivation was prevented by preincubation of the enzymes with NADPH, but not by succinic semialdehyde. There was a linear relationship between isoindole formation and the loss of enzyme activity. Spectrophotometric studies indicated that complete inactivation of the enzyme resulted from the formation of one isoindole derivative per molecule of enzyme, which was formed from the reaction of cysteine and lysine residues with o-phthalaldehyde at or near the enzyme active site.


Assuntos
Inibidores Enzimáticos/farmacologia , Hidroxibutirato Desidrogenase/antagonistas & inibidores , NADP/metabolismo , o-Ftalaldeído/farmacologia , Animais , Sítios de Ligação , Encéfalo/enzimologia , Bovinos , Reagentes de Ligações Cruzadas , Cisteína/química , Indóis/metabolismo , Cinética , Lisina/química
15.
Invest Ophthalmol Vis Sci ; 42(12): 2795-803, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11687520

RESUMO

PURPOSE: To determine the effect of interleukin (IL)-1alpha and tumor necrosis factor (TNF)-alpha on cytokine, chemokine, and receptor expression in corneal stromal cells; the effect of corneal scrape injury on monocyte chemotactic and activating factor (MCAF) expression and monocyte-macrophage influx into the stroma; and the effect of MCAF and granulocyte colony-stimulating factor (G-CSF) microinjection on inflammatory cell infiltration into the stroma. METHODS: Gene array technology was used to evaluate changes in cytokine, chemokine, and receptor gene expression in stromal fibroblasts in response to IL-1alpha and TNFalpha. Expression of MCAF mRNA and protein was monitored with an RNase protection assay and Western blot analysis, respectively. Keratocyte MCAF protein expression in the rabbit cornea was detected with immunocytochemistry. After epithelial scrape injury, monocytes-macrophages were detected in rabbit corneas, by immunocytochemistry for monocyte-macrophage antigen. Inflammatory cell infiltration after MCAF and G-CSF microinjection into the stroma of mouse corneas was monitored with hematoxylin and eosin staining. RESULTS: IL-1alpha or TNFalpha upregulated the expression of several proinflammatory chemokines in stromal fibroblasts in culture. These included G-CSF, MCAF, neutrophil-activating peptide (ENA-78), and monocyte-derived neutrophil chemotactic factor (MDNCF). MCAF mRNA upregulation was confirmed by RNase protection assay, and MCAF protein was detected by Western blot analysis. MCAF protein was detected in keratocytes at 4 hours and 24 hours after epithelial injury, but not in keratocytes in the unwounded cornea. Corneal epithelial injury triggered the influx of monocytes-macrophages into the corneal stroma in the rabbit. Microinjection of MCAF and G-CSF into mouse cornea resulted in the influx of monocytes-macrophages and granulocytes, respectively, into the stroma. CONCLUSIONS: Proinflammatory chemokine induction in keratocytes is mediated by IL-1alpha and TNFalpha. The proinflammatory chemokines produced by the keratocytes probably trigger the influx of inflammatory cells into the stroma after epithelial injury associated with corneal surgery, contact lenses, or trauma.


Assuntos
Movimento Celular/fisiologia , Quimiocinas/biossíntese , Substância Própria/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Interleucina-1/farmacologia , Macrófagos/fisiologia , Monócitos/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Western Blotting , Quimiocina CCL2/farmacologia , Quimiocinas/genética , Substância Própria/metabolismo , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos/farmacologia , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/biossíntese , Receptores CCR2 , Receptores de Quimiocinas/biossíntese , Regulação para Cima
16.
Arch Ophthalmol ; 119(6): 889-96, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11405841

RESUMO

Biological diversity in the wound healing response is thought to be a major factor limiting the predictability of the outcome of refractive surgical procedures such as laser in situ keratomileusis and photorefractive keratectomy. Corneal wound healing is critical to the success of topography-linked or wave front-linked excimer laser ablation to optimize visual performance. This is because of the importance of retaining subtle features of custom ablation and the tendency of epithelial hyperplasia and stromal remodeling to obscure these features following either procedure. The corneal wound healing response is exceedingly complex. Keratocyte apoptosis, which occurs in response to epithelial injury, is the earliest observable event in the wound healing cascades and is therefore an excellent target for pharmacological intervention. Alterations of surgical technique can be designed to limit keratocyte apoptosis and the subsequent events in corneal wound healing. Abnormalities of the cascades could contribute to the pathogenesis of corneal diseases. For example, recent data have suggested that perturbation of the keratocyte apoptosis/mitosis balance could underlie the development of keratoconus in a proportion of patients.


Assuntos
Córnea/fisiologia , Ceratomileuse Assistida por Excimer Laser In Situ , Ceratectomia Fotorrefrativa , Cicatrização/fisiologia , Animais , Apoptose/fisiologia , Córnea/citologia , Células Epiteliais/fisiologia , Fibroblastos/fisiologia , Humanos , Lasers de Excimer , Mitose/fisiologia , Erros de Refração/metabolismo , Procedimentos Cirúrgicos Refrativos
17.
Mol Cells ; 7(1): 13-20, 1997 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-9085259

RESUMO

Succinic semialdehyde reductase (SSR) that catalyzes the reduction of succinic semialdehyde (SSA) to gamma-hydroxybutyrate (GHB) has been identified as one of the NADPH-dependent aldehyde reductases. Reduction of SSA to GHB strongly supports the proposal that GHB biosynthesis may be an important step in the GABA shunt. It is pharmacologically significant in anesthesia, evoking the state of sleep, and an increase in brain dopamine level. Monoclonal antibodies against bovine brain succinic semialdehyde reductase were produced. Using the anti-succinic semialdehyde reductase antibodies, we investigated the distribution of brain succinic semialdehyde reductase in rat brain. The brain tissues were sectioned with a basis on the rat brain atlas of Paxinos and were stained by the immunoperoxidase staining method using monoclonal antibodies. In the section of the frontal lobe, immunoreactive cells were observed in the lateral septal area, the ventral pallidum, which belongs to the substantia innominata. We could observe immunoreactive cells in the reticular thalamic nucleus, which is closely related with 'sleeping', the basal nuclei of Meynert, which is associated with Alzheimer's disease, and hypothalamic nuclei. Immunoreactive cells were also shown in raphe nuclei or the reticular formation of the midbrain, cerebellum, and inferior olivary nuclei of the medulla oblongata. Succinic semialdehyde reductase-immunoreactive cells were distributed extensively in rat brain, especially immunoreactive cells were strongly observed in the areas associated with the limbic system and reticular formation.


Assuntos
Encéfalo/enzimologia , Hidroxibutirato Desidrogenase/metabolismo , Animais , Anticorpos Monoclonais , Encéfalo/anatomia & histologia , Bovinos , Hidroxibutirato Desidrogenase/imunologia , Técnicas Imunoenzimáticas , Sistema Límbico/enzimologia , Microscopia Imunoeletrônica , Ratos , Formação Reticular/enzimologia , Oxibato de Sódio/metabolismo , Distribuição Tecidual , Ácido gama-Aminobutírico/análogos & derivados , Ácido gama-Aminobutírico/metabolismo
18.
AJNR Am J Neuroradiol ; 17(9): 1605-14, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8896609

RESUMO

PURPOSE: To measure the effect of extension, flexion, lateral bending, and axial rotation loads applied to the spine on the anatomic relationship of the spinal nerves in the neural foramen to the ligamentum flavum and the intervertebral disk, anc to determine the effect of disk degeneration on the response to loading. METHODS: Cadaveric lumbar motion segments were examined with CT and MR imaging, loaded with pure moment forces, frozen in situ, reexamined with CT, and sectioned with a cryomicrotome. The morphology of the intervertebral disks was classified on the basis of the appearance of the cryomicrotome sections. The neural foramina were classified as having no evident stenosis, as being stenotic, as having occult stenosis, or as showing resolved stenosis on the basis of the images and sections before and after loading. The stenotic and nonstenotic foramina were stratified by disk level, intervertebral disk classification, and type of loading applied. The effect of spinal level, disk type, and load type on the prevalence of stenosis was studied. RESULTS: On average, extension, flexion, lateral bending, and axial rotation resulted in the ligamentum flavum or intervertebral disk contacting or compressing the spinal nerve in 18% of the neural foramina. Extension loading produced the most cases of nerve root contact, and lateral bending produced the fewest cases. Each of the loading types resulted also in diminished contact between the spinal nerve and the intervertebral disk or ligamentum flavum in some cases. Disk degeneration significantly increased the prevalence of spinal stenosis. All foramina associated with advanced disk degeneration and half of the foramina associated with disks having radial tears of the annulus fibrosus either developed occult stenosis or were stenotic before loading. CONCLUSIONS: The study supports the concept of dynamic spinal stenosis; that is, intermittent stenosis of the neural foramina. Flexion, extension, lateral bending, and axial rotation significantly changed the anatomic relationships of the ligamentum flavum and intervertebral disk to the spinal nerve roots.


Assuntos
Deslocamento do Disco Intervertebral/fisiopatologia , Disco Intervertebral/fisiopatologia , Ligamento Amarelo/fisiopatologia , Vértebras Lombares/fisiopatologia , Nervos Espinhais/fisiopatologia , Estenose Espinal/fisiopatologia , Suporte de Carga/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Humanos , Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/diagnóstico , Ligamento Amarelo/patologia , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/diagnóstico , Síndromes de Compressão Nervosa/fisiopatologia , Raízes Nervosas Espinhais/patologia , Raízes Nervosas Espinhais/fisiopatologia , Nervos Espinhais/patologia , Estenose Espinal/diagnóstico , Tomografia Computadorizada por Raios X
19.
Biotechnol Prog ; 17(5): 958-62, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11587590

RESUMO

A polymer (PDMS: poly(dimethylsiloxane)) microchip for capillary gel electrophoresis that can separate different sizes of DNA molecules in a small experimental scale is presented. This microchip can be easily produced by a simple PDMS molding method against a microfabricated master without the use of elaborate bonding processes. This PDMS microchip could be used as a single use device unlike conventional microchips made of glass, quartz or silicon. The capillary channel on the chip was partially filled with agarose gel that can enhance separation resolution of different sizes of DNA molecules and can shorten the channel length required for the separation of the sample compared to capillary electrophoresis in free-flow or polymer solution format. We discuss the optimal conditions for the gel preparation that could be used in the microchannel. DNA molecules were successfully driven by an electric field and separated to form bands in the range of 100 bp to 1 kbp in a 2.0% agarose-filled microchannel with 8 mm of effective separation length.


Assuntos
Materiais Revestidos Biocompatíveis/química , DNA/isolamento & purificação , Dimetilpolisiloxanos/química , Silicones/química , Eletroforese Capilar/instrumentação , Eletroforese Capilar/normas , Microquímica , Microscopia de Fluorescência , Microscopia de Vídeo , Miniaturização , Peso Molecular , Reprodutibilidade dos Testes , Sefarose
20.
Cornea ; 19(4): 417-20, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10928749

RESUMO

PURPOSE: The purpose of this article is to review available information regarding development, structure, and function of Bowman's layer in the cornea. Disease-related abnormalities of Bowman's layer are described. A hypothesis is advanced to explain the development and maintenance of Bowman's layer. METHODS: Literature review and hypothesis formulation based on previous studies. RESULTS: Information is presented that supports the hypothesis that Bowman's layer forms as a result of cytokine-mediated interactions occurring between corneal epithelial cells and keratocytes that include chemotactic and apoptotic effects on the keratocytes. This hypothesis suggests that Bowman's layer results from such interactions beginning in early development and continuing into adulthood in humans and other animals, such as chickens. CONCLUSIONS: Bowman's layer may be a visible indicator of ongoing stromal-epithelial interactions in the human and have no critical function in corneal physiology. Bowman's layer is commonly destroyed in diseases such as advanced bullous keratopathy where stromal-epithelial interactions may be interrupted. Bowman's-like layers often form in response to epithelium, for example when epithelial plugs extend into the stroma in corneas with radial keratotomy incisions.


Assuntos
Córnea/anatomia & histologia , Córnea/fisiologia , Animais , Apoptose/fisiologia , Membrana Basal/anatomia & histologia , Membrana Basal/fisiologia , Humanos
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