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1.
Mol Cell Neurosci ; 105: 103498, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32389804

RESUMO

The BRICHOS domain is found in human precursor proteins associated with cancer, dementia (Bri2) and amyloid lung disease (proSP-C). Recombinant human (rh) proSP-C and Bri2 BRICHOS domains delay amyloid-ß peptide (Aß) fibril formation and reduce associated toxicity in vitro and their overexpression reduces Aß neurotoxicity in animal models of Alzheimer's disease. After intravenous administration in wild-type mice, rh Bri2, but not proSP-C, BRICHOS was detected in the brain parenchyma, suggesting that Bri2 BRICHOS selectively bypasses the blood-brain barrier (BBB). Here, our objective was to increase the brain delivery of rh proSP-C (trimer of 18 kDa subunits) and Bri2 BRICHOS (monomer to oligomer of 15 kDa subunits) using focused ultrasound combined with intravenous microbubbles (FUS + MB), which enables targeted and transient opening of the BBB. FUS + MB was targeted to one hemisphere of wild type mice and BBB opening in the hippocampal region was confirmed by magnetic resonance imaging. Two hours after FUS + MB brain histology showed no signs of tissue damage and immunohistochemistry showed abundant delivery to the brain parenchyma in 13 out of 16 cases given 10 mg/kg of proSP-C or Bri2 BRICHOS domains. The Bri2, but not proSP-C BRICHOS domain was detected also in the non-targeted hemisphere. ProSP-C and Bri2 BRICHOS domains were taken up by a subset of neurons in the hippocampus and cortex, and were detected to a minor extent in early endosomes. These results indicate that rh Bri2, but not proSP-C, BRICHOS, can be efficiently delivered into the mouse brain parenchyma and that both BRICHOS domains can be internalized by cell-specific mechanisms.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Hipocampo/metabolismo , Chaperonas Moleculares/metabolismo , Neurônios/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Feminino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Microbolhas , Fragmentos de Peptídeos/metabolismo
2.
BMC Health Serv Res ; 19(1): 877, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752866

RESUMO

BACKGROUND: In the move toward value-based care, bundled payments are believed to reduce waste and improve coordination. Some commercial insurers have addressed this through the use of bundled payment, the provision of one fee for all care associated with a given index procedure. This system was pioneered by Medicare, using a population generally over 65 years of age, and despite its adoption by mainstream insurers, little is known of bundled payments' ability to reduce variation or cost in a working-age population. This study uses a universally-insured, nationally-representative population of adults aged 18-65 to examine the effect of bundled payments for five high-cost surgical procedures which are known to vary widely in Medicare reimbursement: hip replacement, knee replacement, coronary artery bypass grafting (CABG), lumbar spinal fusion, and colectomy. METHODS: Five procedures conducted on adults aged 18-65 were identified from the TRICARE database from 2011 to 2014. A 90-day period from index procedure was used to determine episodes of associated post-acute care. Data was sorted by Zip code into hospital referral regions (HRR). Payments were determined from TRICARE reimbursement records, they were subsequently price standardized and adjusted for patient and surgical characteristics. Variation was assessed by stratifying the HRR into quintiles by spending for each index procedure. RESULTS: After adjusting for case mix, significant inter-quintile variation was observed for all procedures, with knee replacement showing the greatest variation in both index surgery (107%) and total cost of care (75%). Readmission was a driver of variation for colectomy and CABG, with absolute cost variation of $17,257 and $13,289 respectively. Other post-acute care spending was low overall (≤$1606, for CABG). CONCLUSIONS: This study demonstrates significant regional variation in total spending for these procedures, but much lower spending for post-acute care than previously demonstrated by similar procedures in Medicare. Targeting post-acute care spending, a common approach taken by providers in bundled payment arrangements with Medicare, may be less fruitful in working aged populations.


Assuntos
Gastos em Saúde/estatística & dados numéricos , Programas de Assistência Gerenciada/economia , Mecanismo de Reembolso , Procedimentos Cirúrgicos Operatórios/economia , Adolescente , Adulto , Idoso , Artroplastia de Quadril/economia , Artroplastia do Joelho/economia , Colectomia/economia , Ponte de Artéria Coronária/economia , Grupos Diagnósticos Relacionados , Feminino , Reforma dos Serviços de Saúde/legislação & jurisprudência , Humanos , Masculino , Pessoa de Meia-Idade , Militares , Fusão Vertebral/economia , Cuidados Semi-Intensivos/economia , Estados Unidos , Veteranos , Adulto Jovem
3.
J Endocrinol Invest ; 41(4): 475-483, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29103133

RESUMO

PURPOSE: Several studies have evaluated the effects of growth hormone (GH) on auxological and biochemical parameters in children with non-GH-deficient, idiopathic short stature (ISS). This study evaluated the efficacy and safety of Growtropin®-II (recombinant human GH) in Korean patients with ISS. METHODS: This was a 1-year, open-label, multicenter, phase III randomized trial of Growtropin®-II in Korean patients with ISS. In total, 70 prepubertal subjects (39 males, 31 females) between 4 and 12 years of age were included in the study. All patients were naive to GH treatment. RESULTS: Annual height velocity was significantly higher in the treatment group (10.68 ± 1.95 cm/year) than the control group (5.72 ± 1.72, p < 0.001). Increases in height and weight standard deviation scores (SDSs) at 26 weeks were 0.63 ± 0.16 and 0.64 ± 0.46, respectively, for the treatment group, and 0.06 ± 0.15 and 0.06 ± 0.28, respectively, for the control group (p < 0.001). Serum insulin-like growth factor (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) increased significantly in the treatment group at week 26 compared to baseline. However, the SDS for body mass index (BMI) at 26 weeks did not change significantly in either group. Growtropin®-II was well tolerated and safe over 1 year of treatment. CONCLUSIONS: One-year GH treatment for prepubertal children with ISS demonstrated increased annualized velocity, height and weight SDSs, and IGF-1 and IGFBP-3 levels, with a favorable safety profile. Further evaluations are needed to determine the optimal dose, final adult height, and long-term effects of ISS treatment.


Assuntos
Estatura/efeitos dos fármacos , Nanismo/tratamento farmacológico , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento Humano/deficiência , Puberdade , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , República da Coreia
4.
J Asthma ; 51(6): 652-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24580369

RESUMO

OBJECTIVES: To identify patients' beliefs or behaviors related to treatment adherence and to assess association between asthma control and adherence in Asian patients with asthma. METHODS: We conducted a cross-sectional observational study of adult patients with asthma from specialist clinics in six Asian countries. Patients who were deemed by their treating physicians to require a maintenance treatment with an inhaler for at least 1 year were recruited. Patients completed a 12-item questionnaire related to health beliefs and behaviors, the 8-item Morisky Medication Adherence Scale (MMAS-8), the Asthma Control Test (ACT™), and the Standardized Asthma Quality of Life Questionnaire (AQLQ-S). RESULTS: Of the 1054 patients recruited, 99% were current users of inhaled corticosteroids. The mean ACT score was 20.0 ± 4.5 and 64% had well-controlled asthma. The mean MMAS-8 score was 5.5 ± 2.0 and 53% were adherent. Adherence was significantly associated with patients' understanding of the disease and inhaler techniques, and with patients' acceptance of inhaler medicines in terms of benefits, safety, convenience, and cost (p < 0.01 for all). In multivariate analysis, three questions related to patients' acceptance of inhaler medicines remained significantly associated with poor adherence, after adjusting for potential confounders: "I am not sure inhaler type medicines work well" (p = 0.001), "Taking medicines more than once a day is inconvenient" (p = 0.002), and "Sometimes I skip my inhaler to use it over a longer period" (p < 0.001). CONCLUSIONS: Our study showed that patients' acceptance of the benefits, convenience and cost of inhaler medications have a significant impact on treatment adherence in the participating Asian countries.


Assuntos
Antiasmáticos/administração & dosagem , Asma/tratamento farmacológico , Asma/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Adesão à Medicação/psicologia , Adulto , Fatores Etários , Idoso , Antiasmáticos/uso terapêutico , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nebulizadores e Vaporizadores , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Qualidade de Vida , Fatores Sexuais , Fatores Socioeconômicos
5.
Allergy ; 68(4): 524-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23414255

RESUMO

BACKGROUND: We conducted Phase 2 of the Asthma Insights and Reality in the Asia-Pacific (AIRIAP 2) survey in 2006 to determine the level of asthma control in this region and the validity of the Asthma Control Test (ACT) and childhood ACT (C-ACT) in relation to asthma control. METHODS: Pediatric participants (0 to <16 years; N = 988) with diagnosed asthma and current asthma symptoms or taking anti-asthma medications were recruited from 12 geographic areas in Asia. The survey consisted of the AIRIAP 2 questionnaire (asthma symptoms, use of urgent healthcare services and anti-asthma medication) and the ACT or C-ACT (English or Chinese translations only), both administered in the participant's preferred language. A symptom control index based on the Global Initiative for Asthma criteria (except lung function) was used to classify asthma control status. RESULTS: Most participants had inadequately controlled asthma ('uncontrolled' = 53.4%, 528/988; 'partly controlled' = 44.0%, 435/988). Only 2.5% (25/988) had 'controlled' asthma. Demand for urgent healthcare services (51.7%, 511/988) and use of short-acting beta-agonists (55.2%, 545/988) was high. The optimal ACT and C-ACT cutoff score for detecting uncontrolled asthma (compared with controlled or partly controlled asthma) was determined to be ≤19 (receiver operating characteristic analysis) with good agreement between the ACT and C-ACT and the symptom control index. CONCLUSIONS: Findings from this survey show that asthma control is suboptimal in many children in the Asia-Pacific region. Practical tools, such as the ACT or C-ACT, may help clinicians assess asthma control and facilitate adjustment of asthma medication.


Assuntos
Asma/prevenção & controle , Inquéritos Epidemiológicos , Adolescente , Antiasmáticos/uso terapêutico , Ásia , Asma/diagnóstico , Asma/tratamento farmacológico , Criança , Pré-Escolar , Estudos Transversais , Humanos , Lactente , Recém-Nascido , Serviços Preventivos de Saúde , Índice de Gravidade de Doença , Inquéritos e Questionários
6.
Nutr Metab Cardiovasc Dis ; 23(10): 967-72, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23021775

RESUMO

BACKGROUND AND AIM: Since using LDL level alone is insufficient as a method to identify individuals with incident coronary artery disease (CAD), other factors may be implicated in the pathogenesis of CAD. Additionally, controversy still remains regarding whether there is an age-related increase in circulating cytokines in healthy individuals. We investigated the influence of age on atherogenicity of LDL and inflammatory markers in healthy women. METHODS AND RESULTS: Two thousand nine hundred forty four healthy women form 30-79 years old (23.3 ± 0.05 kg/m²) were categorized into 5 age groups: 30-39, 40-49, 50-59, 60-69 and 70-79 years. BMI, smoking, drinking, and metabolic syndrome prevalence adjusted mean values of total-cholesterol progressively increased from the group age 30-39 years to the group age 40-49 and 50-59 years and thereafter decreased in the group age 60-69 and 70-79 years. Serum concentrations of C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were higher in women aged 60-79 years than women aged 30-59 years. Plasma ox-LDL levels increased in the group age 50-59 years compared with the group age 30-39 and 40-49 years and further increased in the group age 60-69 and 70-79 years. Mean values of LDL particle size were smaller in women aged 60-79 years than those in women aged 30-59 years. After adjustment for BMI, smoking, drinking, and metabolic syndrome status, age was positively correlated with LDL-cholesterol (r = 0.095, P < 0.001), oxidized LDL (r = 0.305, P < 0.001), hs-CRP (r = 0.150, P < 0.001), TNF-α (r = 0.171, P < 0.001) and IL-6 (r = 0.294, P < 0.001) and negatively with LDL particle size (r = -0.239, P < 0.001). CONCLUSION: Our results indicate that LDL atherogenicity and inflammatory mediators can be better markers of CAD risk than known risk factors such as elevated concentrations of total- and LDL-cholesterol, decreased HDL-cholesterol levels and smoking in old healthy women.


Assuntos
Envelhecimento , Aterosclerose/imunologia , Doença da Artéria Coronariana/imunologia , Citocinas/sangue , Mediadores da Inflamação/sangue , Lipoproteínas LDL/sangue , Estresse Oxidativo , Adulto , Idoso , Aterosclerose/sangue , Aterosclerose/epidemiologia , Aterosclerose/etiologia , Biomarcadores/sangue , Proteína C-Reativa/análise , LDL-Colesterol/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Dislipidemias/sangue , Dislipidemias/imunologia , Dislipidemias/fisiopatologia , Feminino , Humanos , Incidência , Lipoproteínas LDL/química , Pessoa de Meia-Idade , Ambulatório Hospitalar , Tamanho da Partícula , Prevalência , República da Coreia/epidemiologia , Fatores de Risco
7.
Expert Rev Pharmacoecon Outcomes Res ; 23(1): 55-61, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36288082

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) positive for programmed cell death ligand 1 (PD-L1) may be eligible for targeted immunotherapies. Literature does not currently estimate direct costs associated with this population. We aimed to identify the total direct costs associated with PD-L1 positive stage IV NSCLC treated with immunotherapy. METHODS: Using progression-free survival, overall survival, treatment-related serious adverse events leading to hospitalization, and end-of-life resource use, we estimated costs for one year of treatment in this incidence-based study. Data were obtained from online databases, guideline recommendations, clinical trials, and proprietary market share data. We summed the costs of PD-L1 immunohistochemistry (IHC) tests, drugs, hospitalizations, and deaths associated with treatment, estimating the overall cost-of-illness for stage IV NSCLC in the United States in 2021. RESULTS: An estimated 22,711 patients in the US had stage IV NSCLC treated with PD-L1 immunotherapy in 2021. Total 2021 costs were estimated at $3.01 billion. Drugs (including immunotherapy, second-line chemotherapy, and other oncology drugs) accounted for nearly 97% ($2.91 billion) of the total. CONCLUSIONS: PD-L1 positive stage IV NSCLC treatment is a costly condition with annual direct medical costs of $3.01 billion. The primary cost driver was immunotherapy, making up 74.6% of the total cost.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1/metabolismo , Antígeno B7-H1/uso terapêutico , Ligantes , Apoptose , Efeitos Psicossociais da Doença
8.
J Exp Med ; 174(4): 761-7, 1991 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1717630

RESUMO

Macrophage-derived nitric oxide (NO) is cytostatic to tumor cells and microbial pathogens. We tested whether one molecular target for the cytostatic action of NO may be ribonucleotide reductase (RR), a rate-limiting enzyme in DNA synthesis. In a concentration-dependent manner, NO gas and lysates of activated macrophages that generated comparable amounts of NO led to the same degree of inhibition of partially purified RR from L1210 mouse lymphoma cells. Lysates from nonactivated macrophages, which do not produce NO, were noninhibitory. With lysates from activated macrophages, RR was protected by omitting L-arginine or by adding the NO synthase inhibitors diphenyleneiodonium, N omega-methyl-L-arginine, or N omega-amino-L-arginine. L-Arginine, but not D-arginine, abolished the protective effect of N omega-amino-L-arginine. The prototypic pharmacologic inhibitor of RR is hydroxyurea. Its structural resemblance to N omega-hydroxy-L-arginine, a reaction intermediate of NO synthase, prompted us to test if hydroxyurea can generate NO. In the presence of H2O2 and CuSO4, hydroxyurea produced NO2-/NO3-, aerobic reaction products of NO. Addition of morpholine blocked NO2-/NO3- generation from hydroxyurea and led to formation of nitrosomorpholine, as detected by gas chromatography/mass spectrometry. Thus, hydroxyurea can produce an NO-like, nitrosating rectant. L1210 cell DNA synthesis was inhibited completely by activated macrophages or by hydroxyurea, and was partially restored to the same degree in both settings by providing deoxyribonucleosides to bypass the block in RR. Thus, both NO gas and NO generated by activated macrophage lysates inhibit tumor cell RR. The RR inhibitor hydroxyurea can also generate an NO-like species. Similar, partial restoration of tumor cell DNA synthesis by deoxyribonucleosides in the presence of activated macrophages or hydroxyurea suggests that cytostasis by activated macrophages and by hydroxyurea has comparable mechanisms, including, but probably not limited to, inhibition of RR.


Assuntos
Leucemia L1210/enzimologia , Macrófagos/fisiologia , Óxido Nítrico/metabolismo , Ribonucleotídeo Redutases/antagonistas & inibidores , Aminoácido Oxirredutases/metabolismo , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Linhagem Celular , Cobre/farmacologia , Sulfato de Cobre , Ferredoxinas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hidroxiureia/metabolismo , Hidroxiureia/farmacologia , Interferon gama/farmacologia , Cinética , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/farmacologia , Óxido Nítrico Sintase , Nitritos/metabolismo , Ribonucleotídeo Redutases/isolamento & purificação
9.
J Appl Microbiol ; 109(5): 1498-508, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20602653

RESUMO

AIMS: To elucidate the roles of the ß-1,3-endoglucanase EngA in autolysis of the filamentous fungus Aspergillus nidulans and to identify the common regulatory elements of autolytic hydrolases. METHODS AND RESULTS: A ß-1,3-endoglucanase was purified from carbon-starving cultures of A. nidulans. This enzyme is found to be encoded by the engA gene (locus ID: AN0472.3). Functional and gene-expression studies demonstrated that EngA is involved in the autolytic cell wall degradation resulting from carbon starvation of the fungus. Moreover, regulation of engA is found to be dependent on the FluG/BrlA asexual sporulation signalling pathway in submerged culture. The deletion of either engA or chiB (encoding an endochitinase) caused highly reduced production of hydrolases in general. CONCLUSIONS: The ß-1,3-endoglucanase EngA plays a pivotal role in fungal autolysis, and activities of both EngA and ChiB are necessary to orchestrate the expression of autolytic hydrolases. The production of cell wall-degrading enzymes was coordinately controlled in a highly sophisticated and complex manner. SIGNIFICANCE AND IMPACT OF THE STUDY: No information was available on the autolytic glucanase(s) of the euascomycete A. nidulans. This study demonstrates that EngA is a key element in fungal autolysis, and normal activities of both EngA and ChiB are crucial for balanced production of hydrolases.


Assuntos
Aspergillus nidulans/enzimologia , Autólise/enzimologia , Celulase/metabolismo , Aspergillus nidulans/genética , Autólise/genética , Celulase/genética , Quitinases/metabolismo , Regulação Fúngica da Expressão Gênica , Hidrolases/metabolismo , Mutação
10.
J Appl Microbiol ; 107(2): 514-23, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19486415

RESUMO

AIMS: Elucidation of the regulation of ChiB production in Aspergillus nidulans. METHODS AND RESULTS: Mutational inactivation of the A. nidulans chiB gene resulted in a nonautolytic phenotype. To better understand the mechanisms controlling both developmental progression and fungal autolysis, we examined a range of autolysis-associated parameters in A. nidulans developmental and/or autolytic mutants. Investigation of disorganization of mycelial pellets, loss of biomass, extra-/intracellular chitinase activities, ChiB production and chiB mRNA levels in various cultures revealed that, in submerged cultures, initialization of autolysis and stationary phase-induced ChiB production are intimately coupled, and that both processes are controlled by the FluG-BrlA asexual sporulation regulatory pathway. ChiB production does not affect the progression of apoptotic cell death in the aging A. nidulans cultures. CONCLUSIONS: The endochitinase ChiB plays an important role in autolysis of A. nidulans, and its production is initiated by FluG-BrlA signalling. Despite the fact that apoptosis is an inseparable part of fungal autolysis, its regulation is independent to FluG-initiated sporulation signalling. SIGNIFICANCE AND IMPACT OF THE STUDY: Deletion of chiB and fluG homologues in industrial filamentous fungal strains may stabilize the hyphal structures in the autolytic phase of growth and limit the release of autolytic hydrolases into the culture medium.


Assuntos
Aspergillus nidulans/enzimologia , Aspergillus nidulans/genética , Autólise , Quitinases/metabolismo , Proteínas Fúngicas/metabolismo , Anticorpos Antifúngicos/imunologia , Aspergillus nidulans/crescimento & desenvolvimento , Aspergillus nidulans/imunologia , Autólise/genética , Autólise/metabolismo , Biomassa , Quitina/metabolismo , Quitinases/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Regulação Fúngica da Expressão Gênica , Fenótipo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Esporos Fúngicos/genética , Esporos Fúngicos/metabolismo
12.
Invest Ophthalmol Vis Sci ; 38(5): 995-1002, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9112995

RESUMO

PURPOSE: To find the role of nitric oxide (NO) in streptozocin-induced corneal toxicity in rats. METHODS: Sprague-Dawley rats were injected intraperitoneally with streptozotocin (65 mg/kg). For exposure to light, each rat cage was placed in a box surrounded with aluminum foil and illuminated for 6 hours per day with two 20-W fluorescent lamps at a distance of 50 cm. When not exposed to light, each cage was placed in a dark room. Some animals with and without light exposure also were treated with and without streptozotocin treatment. Control animals did not receive streptozotocin and were housed in a dark room 24 hours a day. Each group contained 15 rats. After 1, 3, 7, and 10 days of light exposure, concentrations of nitrite and nitrate, stable oxidation products of NO, were measured in the aqueous humor. Corneal changes also were examined by electron microscopy after 10 days. To examine specific NO-induced histopathologic changes, several rats were injected subconjunctivally with a balanced saline solution containing the NO-generating agent (S-nitroso-N-acetyl-D,L-penicillamine or (Z)-I-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1, 2-diolate]). RESULTS: Concentrations of nitrite and nitrate were highest in the streptozocin-injected rats irradiated while under the fluorescent lamp. On the 10th day of the streptozotocin injection, the concentrations of nitrite and nitrate in streptozocin-treated rats irradiated while under the fluorescent lamp was almost two-and-a-half times greater than that of nontreated rats reared in the dark (111.37 +/- 7.47 microM, 45.43 +/- 3.91 microM, respectively). Slit-lamp biomicroscopy showed that the corneas swelled gradually and opacified by the third day in the irradiated streptozocin-injected group. The corneas became hazy to the point of indistinguishable detail structures by the 10th day, although those of the other rats were relatively clear at the same time. Histopathologically, ultrastructural changes included the remarkable swelling of intracytoplasmic organelles, including mitochondria, and denaturation of collagen fibril was shown in the streptozocin-injected-irradiated rats by the 10th day. The corneas injected with two NO-generating agents, S-nitroso-N-acetyl-D,L-penicillamine and (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1, 2-diolate, showed similar but more severe changes. CONCLUSIONS: Nitric oxide can cause damage to the mitochondria, the most important energy source of the cell, and induce ultrastructural damage to the corneal endothelium and fibroblast. The authors suggest that NO is associated with the development of corneal cytotoxicity and that NO production and subsequent cytotoxicity can be prevented by blocking to photoactivation.


Assuntos
Córnea/efeitos da radiação , Edema da Córnea/etiologia , Opacidade da Córnea/etiologia , Diabetes Mellitus Experimental/complicações , Luz , Animais , Humor Aquoso/metabolismo , Catarata/etiologia , Córnea/efeitos dos fármacos , Córnea/metabolismo , Córnea/ultraestrutura , Edema da Córnea/metabolismo , Edema da Córnea/patologia , Opacidade da Córnea/metabolismo , Opacidade da Córnea/patologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Masculino , Microscopia Eletrônica de Varredura , Nitratos/metabolismo , Óxido Nítrico/biossíntese , Óxido Nítrico/fisiologia , Nitritos/metabolismo , Compostos Nitrosos/farmacologia , Penicilamina/análogos & derivados , Penicilamina/farmacologia , Ratos , Ratos Sprague-Dawley , S-Nitroso-N-Acetilpenicilamina , Estreptozocina
13.
Exp Mol Med ; 30(2): 81-6, 1998 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-9873827

RESUMO

We previously reported an identification of a 77-kDa GTP-binding protein that co-purified with the alpha 1-adrenoceptor following ternary complex formation. In the present paper, we report on the purification and characterization of this GTP-binding protein (termed G alpha h5) isolated from pig heart membranes. After solubilization of pig heart membranes with NaCl, G alpha h5 was purified by sequential chromatographies using DEAE-Cellulose, Q-Sepharose, and GTP-agarose columns. The protein displayed high-affinity GTP gamma S binding which is Mg(2+)-dependent and saturable. The relative order of affinity of nucleotide binding by G alpha h5 was GTP > GDP > ITP >> ATP > or = adenyl-5'-yl imidodiphosphate, which was similar to that observed for other heterotrimeric G-proteins involved in receptor signaling. Moreover, the G alpha h5 demonstrated transglutaminase (TGase) activity that was blocked either by EGTA or GTP gamma S. In support of these observations, the G alpha h5 was recognized by a specific antibody to G alpha h7 or TGase II, indicating a homology with G alpha h (TGase II) family. These results demonstrate that 77-kDa G alpha h5 from pig heart is an alpha 1-adrenoceptor-coupled G alpha h (TGase II) family which has species-specificity in molecular mass.


Assuntos
Proteínas de Ligação ao GTP/isolamento & purificação , Proteínas de Ligação ao GTP/metabolismo , Miocárdio/química , Animais , Sítios de Ligação , Ligação Competitiva , Reações Cruzadas , Proteínas de Ligação ao GTP/imunologia , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Peso Molecular , Receptores Adrenérgicos alfa 1/metabolismo , Suínos , Transglutaminases/metabolismo
14.
Life Sci ; 62(19): 1809-16, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9585112

RESUMO

Our previous studies on alpha1-adrenoceptor signaling suggested that G alpha(h) family is a signal mediator in different species. To elucidate the species-specificity of G alpha(h) family in molecular mass, we used the solubilized membranes from mouse heart and the ternary complex preparations containing alpha1-agonist/receptor/G-protein. Binding of [35S]GTPgammaS and the intensity of the [alpha-32P]GTP photoaffinity labeled protein resulting from activation of the alpha1-adrenoceptor were significantly attenuated by the antagonist, phentolamine. The molecular mass of the specific GTP-binding protein was approximately 72-kDa; homologous with G alpha(h) (transglutaminase II) family. Furthermore, immunological cross-reactivity of ternary complex from mouse heart and purified G alpha(h) from rat, guinea pig, and bovine using anti-G alpha(h7) antibody showed that their molecular masses were distinctly different and approximately 72-kDa G alpha(h) from mouse heart was the lowest molecular mass. Consistent with these observations, in co-immunoprecipitation and co-immunoadsorption of the alpha1-adrenoceptor in the ternary complex preparation by anti-G alpha(h7) antibody, the G alpha(h) family protein tightly coupled to alpha1-adrenoceptor. These results demonstrate the species-specificity of G alpha(h) family in molecular mass, especially the lowest molecular mass in mouse.


Assuntos
GTP Fosfo-Hidrolases/isolamento & purificação , Miocárdio/metabolismo , Receptores Adrenérgicos alfa 1/metabolismo , Transglutaminases/isolamento & purificação , Animais , Bovinos , GTP Fosfo-Hidrolases/imunologia , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Ligação ao GTP/imunologia , Proteínas de Ligação ao GTP/metabolismo , Cobaias , Camundongos , Camundongos Endogâmicos ICR , Proteína 2 Glutamina gama-Glutamiltransferase , Ratos , Receptores Adrenérgicos alfa 1/imunologia , Especificidade da Espécie , Transglutaminases/imunologia , Transglutaminases/metabolismo
15.
Int J Food Microbiol ; 97(2): 137-45, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15541800

RESUMO

The extended single-reaction multiplex PCR (esr-mPCR) developed in this study to detect staphylococcal enterotoxins (SEs), including SEA, SEB, SEC, SED, SEE, SEH, SEI, and SEJ, requires fewer sets of primers than other conventional multiplex PCRs and can be used to detect newly identified staphylococcal enterotoxins SEs more readily. Esr-mPCR analysis of 141 isolates of Staphylococcus aureus obtained from abattoir and livestock product samples revealed that 27 of the S. aureus isolates were toxigenic, and two were 2 multitoxigenic isolates. The most prevalent SE type was SEI followed by SEA and SEH. In addition, we investigated the clonal relatedness of toxigenic S. aureus isolates by arbitrarily primed PCR (AP-PCR). AP-PCR analysis of toxigenic S. aureus isolates revealed that the discriminatory power of AP-PCR was 9 (D=0.81), 8 (D=0.77), and 10 types (D=0.83) with primers AP1, ERIC2, and AP7, respectively. The combination of three each AP-PCR result could rearrange toxigenic S. aureus isolates into 10 types and five subtypes, with the D-value of 0.92. Interestingly, our data showed that toxigenic S. aureus isolates from different sources had different fingerprinting patterns although some of them carried the same types of SE genes. These data suggest that combinations of esr-mPCR and AP-PCR can provide a powerful approach for epidemiological investigation of toxigenic S. aureus isolates.


Assuntos
DNA Bacteriano/genética , Enterotoxinas/genética , Reação em Cadeia da Polimerase/métodos , Staphylococcus aureus/metabolismo , Matadouros , Técnicas de Tipagem Bacteriana , Impressões Digitais de DNA , Primers do DNA , DNA Bacteriano/isolamento & purificação , Enterotoxinas/isolamento & purificação , Microbiologia de Alimentos , Intoxicação Alimentar Estafilocócica/prevenção & controle , Staphylococcus aureus/classificação , Staphylococcus aureus/isolamento & purificação
16.
Acad Emerg Med ; 7(2): 146-56, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10691073

RESUMO

OBJECTIVE: The evaluation of the patient through a comprehensive history and physical examination is considered the cornerstone of medical diagnosis, but many studies suggest that physicians have inadequate physical examination skills. It is unknown whether these skills are reliable and whether they can be adequately acquired through training. The objective of this study was to evaluate the ability of the clinician to detect the presence and discriminate the extent of clinical anemia, fever, and jaundice in an ED or hospitalized patient. METHODS: This was a prospective observational study of a convenience sample of patients presenting to the ED or admitted to the hospital who had a rectal temperature measurement within 30 minutes prior to the observation, serum hematocrit measurement on the day of observation, or serum bilirubin measurement one day prior to the day of observation. Observers' (emergency medicine attending physicians', resident physicians', and rotating medical students') estimated serum hematocrit, rectal temperature, and serum bilirubin values were obtained after each observation. Sensitivity, specificity, positive predictive value, negative predictive value, and mean absolute difference between actual and estimated values were calculated for each observer. RESULTS: The physicians detected the presence or absence of anemia, fever, and jaundice in patients with sensitivities and specificities of approximately 70%. Their predictions varied from the measured value on average by 6.0 +/- 4.6% for serum hematocrit, 1.3 + 1.1 degrees F for rectal temperature, and 3.4 +/- 5.3 mg/dL for serum bilirubin. Observer accuracy decreased when evaluating patients with high and low measured values. CONCLUSIONS: The ability to correctly perform and interpret the physical examination appears to be independent of the observer level of training, patient ethnicity, or patient gender. The examination for pallor, warmth, and jaundice is unreliable in predicting the corresponding laboratory or electronic measurement. Certain anemic, febrile, or jaundiced patients may not be reliably detected solely by a focused physical examination.


Assuntos
Anemia/diagnóstico , Competência Clínica , Serviço Hospitalar de Emergência , Febre/diagnóstico , Icterícia/diagnóstico , Exame Físico , Adolescente , Adulto , Idoso , Bilirrubina/sangue , Biomarcadores/sangue , Temperatura Corporal , Hematócrito , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reto/fisiologia , Sensibilidade e Especificidade , Recursos Humanos
17.
J Food Prot ; 66(9): 1604-10, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14503713

RESUMO

An efficacy test of GC-100X, a noncorrosive alkaline ionic fluid (pH 12) composed of free radicals and supplemented with xylitol, was carried out against six major foodborne pathogens-Staphylococcus aureus FRI 913, Salmonella enterica serovar Enteritidis ATCC 13076, S. enterica serovar Typhimurium DT104 Korean isolate, Vibrio parahaemolyticus ATCC 17803, Escherichia coli O157:H7 ATCC 43894, and Pseudomonas aeruginosa KCTC 1637-at three different temperatures (4, 25, and 36 degrees C) with or without organic load (2% yeast extract). Results revealed a more than 4-log10 (CFU/ml) reduction (1.0 x 10(4) CFU/ml reduction) against all pathogens reacted at 37 degrees C for 3 h in the absence of organic material. GC-100X solution diluted with an equal volume of distilled or standard hard water (300 ppm CaCO3) showed effective bactericidal activity, particularly against gram-negative bacteria. Washing efficacy of GC-100X solution was compared against E. coli O157:H7 on cherry tomato surfaces with those of a commercially used detergent and chlorine water (100 ppm). Viable cell counts of E. coli O157:H7 that had penetrated to the cores of tomatoes after sanitizing treatment revealed that GC-100X stock and its 5% diluted solutions had similar washing effects to 100-ppm chlorine water and were more effective than the other kitchen detergent. These results indicate that GC-100X has good bactericidal and sanitizing activities and is useful as a new sanitizer for food safety and kitchen hygiene.


Assuntos
Desinfetantes/farmacologia , Escherichia coli O157/efeitos dos fármacos , Solanum lycopersicum/microbiologia , Cloro/farmacologia , Contagem de Colônia Microbiana , Escherichia coli O157/crescimento & desenvolvimento , Microbiologia de Alimentos , Concentração de Íons de Hidrogênio , Temperatura , Fatores de Tempo , Resultado do Tratamento , Xilitol/farmacologia
18.
Adv Exp Med Biol ; 506(Pt A): 687-95, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12613978

RESUMO

For the first time, the current series of studies provide a possible pathophysiologic mechanism of NO-induced ocular surface disease. NO is present in tear and aqueous humor and is suspected of having an important physiological role in maintaining normal homeostasis of the ocular surface. NO concentrations are higher in aqueous humor compared to tears, though some variability exists between different species. When inflammation was induced by PTK wounding or LPS, three forms of NOS expression were seen in corneal cells. Each isoform of NOS was expressed uniquely according to the specific location of inflammation. When concentrations of NO peaked, the levels of iNOS were markedly increased in fibroblasts and inflammatory cells. The correlation between NO and inflammation was confirmed by treatment with NOS inhibitor, which abrogated the amount of both NO and inflammation. The tissue damage by NO was measured by nitrotyrosine formation. Damage was detected mainly in inflammatory cells, especially those localized in and around the limbal vessel. It is likely that expression of iNOS in limbal fibroblasts has other roles related to survival of limbal stem cells and fibroblasts as well. Because the main source of NO are fibroblasts, we were able to determine the effect of various concentrations of NO on cell viability using a fibroblast culture system. Cell viability increased in dose dependent manner from 10 microM to 500 microM of the NO generator SNAP, but decreased at concentrations above 1000 microM, suggesting that the in vivo mechanism of cell death was indirect, through specific biologic pathways. Therefore, the pathophysiological mechanism of NO action is bimodal with a toxicological component in ocular surface diseases. Furthermore, its concentration and interaction with other oxygen mediators appear to vary depending on the degree of inflammation.


Assuntos
Doenças da Córnea/fisiopatologia , Óxido Nítrico/metabolismo , Animais , Apoptose/fisiologia , Humor Aquoso/metabolismo , Córnea/efeitos dos fármacos , Córnea/metabolismo , Córnea/patologia , Córnea/fisiopatologia , Doenças da Córnea/patologia , Meios de Cultura Livres de Soro/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Humanos , Necrose , Concentração Osmolar , Ácido Peroxinitroso/biossíntese , Coelhos , Ratos , Ratos Sprague-Dawley , Lágrimas/metabolismo
19.
Korean J Ophthalmol ; 15(2): 59-66, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11811584

RESUMO

The role of nitric oxide (NO) in ocular surface diseases remains unknown. We investigated the conditions leading to increase NO generation in tears and the main sources of ocular surface tissue. We evaluated the possibility of a dual action (cell survival or cell death) depending on the amount of NO. The concentration of nitrite plus nitrate, the stable end-product of NO, was measured in the tears of various ocular surface diseases. We also examined the main source of nitric oxide synthase (NOS) using immunohistochemical staining & Western blot analysis. When cultured human corneal fibroblasts were treated with NO producing donor with or without serum, the viability of cells was studied. We found that sources of NO in ocular surface tissue primarily included corneal epithelium, fibroblasts, endothelium and inflammatory cells. Three forms of NOS (eNOS, bNOS, & iNOS) were expressed in experimentally induced inflammation. Cell death by NO revealed TUNEL positive staining, however in the EM finding, this NO specific cell death was an atypical necrosis showing perinuclear large vacuolization and mitochondrial swelling. In the fibroblasts culture system, the NO donor (SNAP, S-nitroso-N-acetyl-D, L-penicillamine) prevented the death of corneal fibroblasts caused by serum deprivation in a dose dependent manner up to 500 m SNAP, although a higher dose decreased cell viability. This study suggested that NO might act as a double-edged sword in ocular surface disease depending on the degree of inflammatory condition related with NO concentration.


Assuntos
Oftalmopatias/fisiopatologia , Óxido Nítrico/metabolismo , Animais , Células Cultivadas , Córnea/metabolismo , Humanos , Lágrimas/metabolismo
20.
Rev Sci Instrum ; 83(9): 093704, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23020380

RESUMO

A fast microtomography system for high-resolution high-speed imaging has been developed using bright monochromatic x-rays at the BL29XU beamline of SPring-8. The shortest scan time for microtomography we attained was 0.25 s in 1.25 µm effective pixel size by combining the bright monochromatic x-rays, a fast rotating sample stage, and a high performance x-ray imaging detector. The feasibility of the tomography system was successfully demonstrated by visualization of rising bubbles in a viscous liquid, an interesting issue in multiphase flow physics. This system also provides a high spatial (a measurable feature size of 300 nm) or a very high temporal (9.8 µs) resolution in radiographs.


Assuntos
Microtecnologia/instrumentação , Tomografia por Raios X/instrumentação , Cor , Estudos de Viabilidade , Imageamento Tridimensional , Rotação , Fatores de Tempo
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