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1.
J Phys Chem B ; 125(37): 10452-10458, 2021 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-34520210

RESUMO

Bioluminescence of a number of marine organisms is conditioned by Ca2+-regulated photoprotein (CaRP) with coelenterazine as the reaction substrate. The reaction product, coelenteramide, at the first singlet excited state (S1) is the emitter of CaRP. The S1-state coelenteramide is produced via the decomposition of coelenterazine dioxetanone. Experiments suggested that the neutral S1-coelenteramide is the primary emitter species. This supposition contradicts with theoretical calculations showing that the anionic S1-coelenteramide is a primary product of the decomposition of coelenterazine dioxetanone. In this study, applying molecular dynamic (MD) simulations and the hybrid quantum mechanics/molecular mechanics (QM/MM) method, we investigated a proton-transfer (PT) process taking place in CaRP obelin from Obelia longissima for emitter formation. Our calculations demonstrate a concerted PT process with a water molecule as a bridge between anionic S1-coelenteramide and the nearest histidine residue. The low activation barrier as well as the strong hydrogen-bond network between the proton donor and the proton acceptor suggests a fast PT process comparable with that of the lifetime of excited anionic S1-coelenteramide. The existence of the PT process eliminates the discrepancy between experimental and theoretical studies. The fast PT process at emitter formation can also take place in other CaRPs.


Assuntos
Hidrozoários , Prótons , Animais , Ligação de Hidrogênio , Proteínas Luminescentes
2.
J Geriatr Cardiol ; 18(8): 645-653, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34527030

RESUMO

BACKGROUND: Association between tea consumption and incident hypertension remains uncertain. This study conducted to examine the health effects of tea consumption on blood pressure progression and hypertension incidence. METHODS: A population-based cohort of 38,913 Chinese participants without hypertension at baseline were included in the current study. Information on tea consumption was collected through standardized questionnaires. Associations of tea consumption with blood pressure progression and incident hypertension were analyzed using logistic regression models and Cox proportional hazards regression models, respectively. RESULTS: During a median follow-up of 5.9 years, 17,657 individuals had experienced progression to a higher blood pressure stage and 5,935 individuals had developed hypertension. In multivariate analyses, habitual tea drinkers (≥ 3 times/week for at least six months) had a 17% lower risk for blood pressure progression [odds ratio (OR) = 0.83, 95% CI: 0.79-0.88] and a 14% decreased risk for incident hypertension [hazard ratio (HR) = 0.86, 95% CI: 0.80-0.91] compared with non-habitual tea drinkers. Individuals in different baseline blood pressure groups could obtain similar benefit from habitual tea drinking. In terms of tea consumption amount, an inverse, linear dose-response relation between monthly consumption of tea leaves and risk of blood pressure progression was observed, while the risk of incident hypertension did not reduce further after consuming around 100 g of tea leaves per month. CONCLUSIONS: Our study demonstrated that habitual tea consumption could provide preventive effect against blood pressure progression and hypertension incidence.

3.
J Geriatr Cardiol ; 18(3): 175-184, 2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33907547

RESUMO

OBJECTIVES: Moderate to vigorous physical activity is recommended to prevent hypertension according to the current guidelines. However, the degree to which the total physical activity (TPA) and its changes benefit normotensives and hypertensives is uncertain. We aimed to examine the effects of TPA and its changes on the incidence, progression, and remission of hypertension in the large-scale prospective cohorts. METHODS: A total of 73,077 participants (55,101 normotensives and 17,976 hypertensives) were eligible for TPA analyses. During a mean follow-up of 7.16 years (394,038 person-years), 12,211 hypertension cases were identified. TPA was estimated as metabolic equivalents and categorized into quartiles. Cox proportional hazards regression and multivariable logistic regression were used to estimate associations of TPA and changes in TPA with incident hypertension and progression/remission of hypertension. RESULTS: Compared with the lowest quartile of TPA, normotensives at the third and the highest quartile had a decreased risk of incident hypertension, with hazard ratios (HRs) of 0.86 [95% confidence interval (CI): 0.81-0.91] and 0.81 (95% CI: 0.77-0.86), respectively. Hypertensives at the highest quartile of TPA demonstrated a decreased risk of progression of hypertension [odds ratio (OR) = 0.87, 95% CI: 0.79-0.95], and an increased probability of hypertension remission (OR = 1.17, 95% CI: 1.05-1.29). Moreover, getting active from a sedentary lifestyle during the follow-up period could reduce 25% (HR = 0.75, 95% CI: 0.58-0.96) risk of incident hypertension, whereas those becoming sedentary did not achieve benefit from initially being active. CONCLUSIONS: Our findings indicated that increasing and maintaining TPA levels could benefit normotensives, whereas higher TPA levels were needed to effectively control progression and improve remission of hypertension. Physical activity played undoubtedly an essential role in both primary and secondary prevention of hypertension.

5.
Crit Care ; 19: 49, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25888250

RESUMO

INTRODUCTION: Mortality and disability following ischemic stroke (IS) remains unacceptably high with respect to the conventional therapies. This study tested the effect of erythropoietin (EPO) on long-term neurological outcome in patients after acute IS. This study aimed to evaluate the safety and efficacy of two consecutive doses of EPO (5,000 IU/dose, subcutaneously administered at 48 hours and 72 hours after acute IS) on improving the 90-day combined endpoint of recurrent stroke or death that has been previously reported. A secondary objective was to evaluate the long-term (that is, five years) outcome of patients who received EPO. METHODS: This was a prospective, randomized, placebo-controlled trial that was conducted between October 2008 and March 2010 in a tertiary referral center. IS stroke patients who were eligible for EPO therapy were enrolled into the study. RESULTS: The results showed that long-term recurrent stroke and mortality did not differ between group 1 (placebo-control; n = 71) and group 2 (EPO-treated; n = 71). Long-term Barthel index of <35 (defining a severe neurological deficit) was lower in group 2 than group 1 (P = 0.007). Multiple-stepwise logistic-regression analysis showed that EPO therapy was significantly and independently predictive of freedom from a Barthel index of <35 (P = 0.029). Long-term major adverse neurological event (MANE; defined as: death, recurrent stroke, or long-term Barthel index < 35) was lower in group 2 than group 1 (P = 0.04). Log-Rank test showed that MANE-free rate was higher in group 2 than group 1 (P = 0.031). Multiple-stepwise Cox-regression analysis showed that EPO therapy and higher Barthel Index at day 90 were independently predictive of freedom from long-term MANE (all P <0.04). CONCLUSION: EPO therapy significantly improved long-term neurological outcomes in patients after IS. TRIAL REGISTRATION: ISRCTN71371114 . Registered 10 October 2008.


Assuntos
Eritropoetina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Isquemia Encefálica/tratamento farmacológico , Células Progenitoras Endoteliais/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo , Resultado do Tratamento
6.
J Atheroscler Thromb ; 21(2): 129-39, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24025753

RESUMO

AIMS: The association between an elevated serum neopterin level and the development of coronary artery complex lesions has been extensively assessed; however, the correlation between the serum neopterin level and the development of carotid artery stenosis has seldom been reported. This study tested whether this biomarker is increased in patients with severe carotid artery stenosis(≥70%) undergoing carotid artery(CA) stenting and investigated independent predictors of an increased circulating neopterin level. METHODS: Fifty patients with severe CA stenosis(CAS) undergoing CA stenting were consecutively enrolled in this study from January 2009 through December 2011. The serum neopterin levels of age- and gender-matched acute ischemic stroke(AIS) patients(n=120) and control subjects(CS)(n=33) were also measured. A blood sample was prospectively collected from each patient in the catheterization room. RESULTS: The serum levels of neopterin were significantly higher in the CAS patients than in the AIS patients or CS and significantly higher in the AIS patients than in the CS(all p<0.001). An analysis of the variables of 170 patients(CAS+AIS) demonstrated that age, a previous history of stroke and severe CAS were significantly correlated with an increased serum level of neopterin(all p<0.005). A multivariate binary logistic regression analysis of the severe CAS patients(n=50) demonstrated that age and the creatinine level were independent predictors of a high neopterin level(neopterin level ≥16.52 ng/dL, i.e., according to the median value of neopterin)(all p<0.05). CONCLUSIONS: The circulating neopterin levels are significantly higher in patients with severe CAS than in those with AIS. The presence of CAS, age and the creatinine level were significantly correlated with an increased serum neopterin level.


Assuntos
Biomarcadores/sangue , Estenose das Carótidas/diagnóstico , Transtornos Cerebrovasculares/complicações , Neopterina/sangue , Stents , Idoso , Estenose das Carótidas/sangue , Estenose das Carótidas/etiologia , Estenose das Carótidas/cirurgia , Estudos de Casos e Controles , Transtornos Cerebrovasculares/sangue , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Fatores de Risco , Índice de Gravidade de Doença
7.
Chemistry ; 19(26): 8466-72, 2013 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-23670851

RESUMO

Aequorea victoria is a type of jellyfish that is known by its famous protein, green fluorescent protein (GFP), which has been widely used as a probe in many fields. Aequorea has another important protein, aequorin, which is one of the members of the EF-hand calcium-binding protein family. Aequorin has been used for intracellular calcium measurements for three decades, but its bioluminescence mechanism remains largely unknown. One of the important reasons is the lack of clear and reliable knowledge about the light emitters, which are complex. Several neutral and anionic forms exist in chemiexcited, bioluminescent, and fluorescent states and are connected with the H-bond network of the binding cavity in the protein. We first theoretically investigated aequorin chemiluminescence, bioluminescence, and fluorescence in real proteins by performing hybrid quantum mechanics and molecular mechanics methods combined with a molecular dynamics method. For the first time, this study reported the origin and clear differences in the chemiluminescence, bioluminescence and fluorescence of aequorin, which is important for understanding the bioluminescence not only of jellyfish, but also of many other marine organisms (that have the same coelenterazine caved in different coelenterazine-type luciferases).


Assuntos
Equorina/química , Hidrozoários/metabolismo , Substâncias Luminescentes/química , Equorina/metabolismo , Animais , Benzenoacetamidas/química , Benzenoacetamidas/metabolismo , Substâncias Luminescentes/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Pirazinas/química , Pirazinas/metabolismo , Teoria Quântica
8.
Clin Neurol Neurosurg ; 115(9): 1709-15, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23611735

RESUMO

OBJECTIVE: Stenotrophomonas (S.) maltophilia is an uncommon pathogen of adult bacterial meningitis (ABM). METHODS: The clinical characteristics of six S. maltophilia ABM cases, collected during a study period of nine years (2001-2009) were included. In the related literature, 13 S. maltophilia ABM cases were reported, and their clinical data were also collected. RESULTS: The 19 S. maltophilia ABM cases included 11 men and 8 women, aged 28-70 years. Of these 19 cases, 89.5% (17/19) had underlying neurosurgical (NS) conditions as the preceding event. Before the development of S. maltophilia ABM, 52.6% (10/19) of them had long stays in hospital and 63.2% (12/19) had undergone antibiotic treatment. Among the implicated S. maltophilia cases, three strains were found to have a resistance to sulfamethoxazole-trimethoprim (SMZ-TMP). Two of our five cases had resistant strains to levofloxacin. Among the antibiotics chosen for treatment, SMZ-TMP was the most common followed by quinolone (ciprofloxacin, levofloxacin, moxifloxacin). The therapeutic results showed 2 cases expired while the other 17 cases survived. CONCLUSIONS: S. maltophilia ABM usually develops in patients with a preceding neurosurgical condition, a long hospital stay and antibiotic use. SMZ-TMP and quinolones, especially the ciprofloxacin, are the major antibiotic used. This study also shows the emergence of clinical S. maltophilia strains which are not susceptible to SMZ-TMP and quinolones and this development may pose a more serious threat in the near future because treatment options may become depleted and limited despite the mortality rate of this specific group of ABM not being high at this time.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/etiologia , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/etiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/tratamento farmacológico , Stenotrophomonas maltophilia , Adulto , Idoso , Antibacterianos/farmacologia , Infecções do Sistema Nervoso Central/epidemiologia , Farmacorresistência Bacteriana , Feminino , Fluoroquinolonas/farmacologia , Fluoroquinolonas/uso terapêutico , Infecções por Bactérias Gram-Negativas/microbiologia , Hospitalização , Humanos , Incidência , Tempo de Internação , Masculino , Meningites Bacterianas/microbiologia , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Stenotrophomonas maltophilia/efeitos dos fármacos , Combinação Trimetoprima e Sulfametoxazol/farmacologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico
9.
Clin Biochem ; 45(18): 1596-601, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22892193

RESUMO

BACKGROUND: We hypothesized that serum level of neopterin is significantly predictive of prognostic outcome in patients after acute ischemic stroke (IS). METHODS: Between November 2008 and May 2010, serum levels of neopterin were prospectively collected at 48 h after acute IS in 157 patients. RESULTS: Serum neopterin levels were substantially higher in patients with severe neurological impairment [National institutes of Health Stroke Scale (NIHSS) score ≥12] than in those with NIHSS <12 (p<0.008). Furthermore, Spearman's test showed a strongly positive correlation between neopterin level and NIHSS (p=0.003). Multiple logistic regression analysis demonstrated that serum neopterin level was strongly and independently predictive of NIHSS ≥12 (p=0.002) at 48 h after acute IS and 90-day major adverse clinical outcome (defined as NIHSS≥12, recurrent stroke or death) (p=0.003). CONCLUSION: Serum level of neopterin was notably increased after acute IS. This biomarker was strongly and independently predictive of 90-day unfavorable clinical outcome in patients after acute IS.


Assuntos
Isquemia Encefálica/sangue , Isquemia Encefálica/complicações , Neopterina/sangue , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , Idoso , Estenose das Carótidas/sangue , Estenose das Carótidas/complicações , Estudos de Casos e Controles , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Resultado do Tratamento
10.
J Atheroscler Thromb ; 19(6): 523-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22447189

RESUMO

AIM: To evaluate the potential of the lipoprotein-associated phospholipase A(2) (Lp-PLA(2) level as a biomarker in the prediction of prognostic outcome in patients with acute ischemic stroke (IS). METHODS: From October 2008 to March 2010, 130 patients with acute IS were prospectively enrolled in the study and their medical records were reviewed. A blood sample was collected from each patient 48 hours after acute IS, as well as from 20 healthy volunteers as controls. Messenger-RNA (mRNA) expression of Lp-PLA(2) of peripheral-blood mononuclear cells (PBMNCs) relative to that of ß actin was measured using quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Patients with acute IS exhibited significantly higher Lp-PLA(2) mRNA expression of PBMNCs than the control group (p <0.0001). Lp-PLA(2) mRNA expression of PBMNCs in patients with a major adverse clinical outcome (MACO) (defined as recurrent stroke or death) within 90 days was significantly higher than in patients without MACO (p=0.006). Furthermore, elevated Lp-PLA(2) mRNA expression was strongly associated with old age, diabetes mellitus, a positive history of significant coronary arterial disease and significant stenosis of the extra-cranial carotid arteries (all p <0.04), and positively correlated with the body mass index, leukocyte count, and serum levels of total cholesterol and low-density lipoprotein cholesterol. Multivariate analysis revealed that Lp-PLA(2) mRNA expression of PBMNCs was a significant independent predictor of MACO within 90 days (p= 0.011). CONCLUSION: Elevated Lp-PLA(2) mRNA expression of PBMNCs seems to be a potential biomarker for predicting an unfavorable outcome in patients with acute IS.


Assuntos
1-Alquil-2-acetilglicerofosfocolina Esterase/sangue , Biomarcadores/sangue , Isquemia/sangue , Leucócitos Mononucleares/metabolismo , Acidente Vascular Cerebral/sangue , 1-Alquil-2-acetilglicerofosfocolina Esterase/genética , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Isquemia/diagnóstico , Isquemia/genética , Masculino , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/genética
11.
J Chem Theory Comput ; 8(8): 2796-807, 2012 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26592121

RESUMO

A systematic investigation of the structural and spectroscopic properties of coelenteramide has been performed at the TD-CAM-B3LYP/6-31+G(d,p) level of theory, including various fluorescence and chemiluminescence states. The influence of geometric conformations, solvent polarity, protonation state, and the covalent character of the O-H bond of the hydroxyphenyl moiety were carefully studied. Striking differences in geometries and electronic structures among the states responsible for light emission were characterized. All fluorescence states can be described as a limited charge transfer process for a planar amide moiety. However, the chemiluminescence state is characterized by a much larger charge transfer that takes place over a longer distance. Moreover, the chemiluminescent coelenteramide structure exhibits an amide moiety that is no longer planar, in agreement with recent, more accurate ab initio results [Roca-Sanjuán et al. J. Chem. Theory Comput.2011, 7, 4060]. Because the chemiluminescence state appears to be completely dark, a new mechanism is tentatively introduced for this process.

12.
Clin Neurol Neurosurg ; 114(6): 572-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22206858

RESUMO

OBJECTIVE: Spinal epidural abscess (SEA) is a devastating infectious disease, which may result in neurologic sequelae. Staphylococcus (S.) aureus is a common pathogen of SEA. Here, we analyzed the clinical characteristics and laboratory data of adult patients with S. aureus SEA and compared the clinical characteristics of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) infections. METHODS: Between 2003 and 2008, we collected data regarding 29 adult cases of S. aureus SEA and analyzed the clinical presentations, magnetic resonance (MR) imaging features, therapeutic outcome, and prognostic factors. Antibiotic susceptibility test results of 11 implicated MRSA strains were also further analyzed. RESULTS: We identified 17 MSSA strains and 12 MRSA strains. Lumbar and lumbosacral spine segments were the most commonly involved segments. All 29 patients had back pain. Other findings included sensory abnormalities (25), motor weakness (21), fever (16), bladder dysfunction (16), and altered consciousness (3). Disease onset at admission was acute in 6 cases and chronic in 23. The stages of disease severity were early stage in 9 and late stage in 20. After therapy, 21 patients had a good prognosis and 8 had a poor prognosis. Significant prognostic factors included older age (>70years), presence of diabetes mellitus, adrenal insufficiency, and MRSA infection. The prognosis alone was clinically different between patients with MSSA and MRSA infections. CONCLUSIONS: Patients with localized back pain, particularly those with a fever and compromised immune system, should undergo MR imaging to ensure an early diagnosis and management.


Assuntos
Antibacterianos/uso terapêutico , Abscesso Epidural/tratamento farmacológico , Abscesso Epidural/microbiologia , Doenças da Medula Espinal/tratamento farmacológico , Doenças da Medula Espinal/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Abscesso Epidural/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Prognóstico , Doenças da Medula Espinal/patologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus , Resultado do Tratamento , Adulto Jovem
13.
J Chem Phys ; 134(11): 114303, 2011 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-21428615

RESUMO

Quantum chemical calculations with relativistic effects were performed on the photodissociation of o-, m-, and p-bromofluorobenzene (o-, m-, and p-BrFPh) at 266 nm. The method of multistate second-order multiconfigurational perturbation theory in conjunction with spin-orbit interaction through complete active space state interaction was employed to calculate the potential energy curves for the ground and low-lying excited states of o-, m-, and p-BrFPh along their photodissociation reaction coordinates. The dissociation mechanisms with products of Br((2)P(3∕2)) and Br(∗)((2)P(1∕2)) states were clarified with the computed potential energy curves and the surface crossings. The current calculations augmented previous theoretical investigations by including relativistic effects and resolved some differences of experimental assignment regarding the dissociation channels of o-, m-, and p-BrFPh.

14.
J Clin Neurosci ; 18(3): 364-8, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21247770

RESUMO

From January 1993 to December 2006 we analyzed the clinical characteristics of patients with hepatocellular carcinoma (HCC) with central nervous system (CNS) metastasis at the Kaohsiung Chang Gung Memorial Hospital, Taiwan. Forty-six patients with HCC and CNS metastasis were identified, of whom 36 had intracranial metastasis and 10 had spinal metastasis. The clinical presentations, laboratory data and imaging studies were collected and analyzed. The age at the time of HCC diagnosis ranged from 34 to 78 years; CNS metastasis occurred between 0 and 85 months after diagnosis and death followed between 0 and 93 months later. The Glasgow Coma Scale (GCS) score at the time of CNS metastasis ranged from 7 to 15 and the Child-Pugh score at diagnosis of HCC ranged from 5 to 15. Patients with spinal metastasis had a higher GCS score and lower Child-Pugh score at diagnosis. None of the serum biochemical studies showed unique abnormalities. From the data currently available, intracranial metastasis is the most common site of CNS metastasis of HCC. Advances in treating and diagnosing HCC have improved patient outcomes remarkably; however, CNS metastasis continues to have a grave prognosis. Without a specific biomarker for predicting CNS involvement in HCC, a high index of suspicion for the diagnosis should be maintained, particularly in HCC hyperendemic areas such as Taiwan.


Assuntos
Neoplasias Encefálicas/secundário , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Neoplasias da Medula Espinal/secundário , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Carcinoma Hepatocelular/mortalidade , Feminino , Escala de Coma de Glasgow , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasias da Medula Espinal/mortalidade
15.
J Clin Neurosci ; 18(2): 213-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21185728

RESUMO

Gram-negative (G(-)) bacterial spinal epidural abscess (SEA) in adults is uncommon. Of the 42 adult patients with bacterial SEA admitted to the Chang Gung Memorial Hospital - Kaohsiung, between 2003 and 2007, 12 with G(-) SEA were included in this study. Of these 12 patients, seven were men and five were women; their ages ranged between 17 years and 81 years (median=72.5 years, mean=62.5 years). The patients were admitted at different stages of symptom onset (four were in the acute stage and four each in the subacute and chronic stages) and at different levels of neurologic deficit severity, ranging from back pain to paraplegia. Of these 12 patients, 11 had a medical and/or neurosurgical condition as the preceding event and four had a concomitant infection at other sites. Back pain (83%, 10/12) was the most common clinical presentation, followed by paraparesis (50%, 6/12), radiating pain (33%, 4/12), and urinary retention (25%, 3/12). The following causative G(-) pathogens were detected: Klebsiella pneumoniae (three patients), Salmonella spp. (three), Escherichia coli (two), Enterobacter spp. (two), Aeromonas hydrophila (one), and Prevotella melaninogenica (one). Both Enterobacter strains were resistant to multiple antibiotics. Of the 12 patients, eight (66.7%) had spontaneous SEA, whereas the remaining four had postneurosurgical SEA. Thoracic, lumbar, and thoracolumbar spine segments were the most commonly affected. After receiving medical and/or surgical treatment, 10 of the 12 patients (83%) survived, and all 10 recovered well. In conclusion, G(-) bacterial SEA accounted for 28.5% (12/42) of adult SEA. The causative G(-) pathogens found in this study were different from those reported in Western countries, and the strains noted in our study had multiple antibiotic resistance. Our findings suggest that the choice of initial empirical antibiotics for SEA should be carefully considered.


Assuntos
Antibacterianos/uso terapêutico , Abscesso Epidural/microbiologia , Abscesso Epidural/terapia , Espaço Epidural/microbiologia , Infecções por Bactérias Gram-Negativas/terapia , Canal Medular/microbiologia , Adolescente , Adulto , Idoso , Abscesso Epidural/epidemiologia , Espaço Epidural/patologia , Feminino , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Canal Medular/patologia , Adulto Jovem
16.
Chin Med J (Engl) ; 124(22): 3702-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22340227

RESUMO

BACKGROUND: Increased blood pressure and elevated total cholesterol (TC) level are the two most important modifiable risk factors of cardiovascular disease (CVD) in the world. Hypertension and hypercholesterolemia co-exist more often than would be expected and whether there is a synergistic impact on fatal CVD between elevated TC and hypertension need to be further examined in Chinese population. METHODS: We conducted a cohort study which recruited 5092 Chinese male steelworkers aged 18 - 74 years in 1974 - 1980 and followed up for an average of 20.84 years. Totally 302 fatal CVD events were documented by the year of 2001. Cox proportional hazards regression models were undertaken to adjust for baseline variables with fatal CVD events as the outcome variable. Additive interaction model was used to evaluate the interaction between elevated TC and hypertension. RESULTS: Hypercholesterolemia and hypertension were significantly associated with an increased hazard ratio (HR) of fatal CVD (1.67 (95%CI 1.18 - 2.38) and 2.91 (95%CI 2.23 - 3.80) respectively. Compared to participants with normotension and TC < 240 mg/dl, the HRs were 1.11 (95%CI 0.56 - 2.21), 2.74 (95%CI 2.07 - 3.64) for hypercholesterolemia and hypertension respectively, and 5.51 (95%CI 3.58 - 8.46) for participants with both risk factors. There was an additive interaction with a 2.65 (95%CI 0.45 - 4.85) relative excess risk (RERI) between hypercholesterolemia and hypertension on CVD. CONCLUSION: We found that the risk of fatal CVD was significantly associated with an additive interaction due to hypercholesterolemia and hypertension besides a conventional main effect derived from either of them, which highlights that the prevention and treatment of both risk factors might improve the individual risk profile thus reduce the CVD mortality.


Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Colesterol/sangue , Hipercolesterolemia/complicações , Hipertensão/complicações , Aço , Adolescente , Adulto , Idoso , Humanos , Hipercolesterolemia/sangue , Hipertensão/sangue , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
J Chem Theory Comput ; 7(3): 798-803, 2011 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-26596309

RESUMO

This is a systematic theoretical investigation on all the possible light emitters of firefly using a multireference method. Six chemical forms of oxyluciferin (OxyLH2) molecules/anions were studied by a multistate complete active space second-order perturbation (MS-CASPT2) method in vacuum and dimethyl sulfoxide. The calculated results and subsequent analysis excluded enol-OxyLH2, keto-OxyLH2, and enolate-OxyLH(-) as possible light emitters. The remaining three candidates, phenolate-enol-OxyLH(-), phenolate-keto-OxyLH(-), and OxyL(2-), were further investigated in protein by a MS-CASPT2/molecular mechanics (MM) study to explain the natural bioluminescence of firefly. By comparison of the MS-CASPT2/MM calculated results of phenolate-enol-OxyLH(-), phenolate-keto-OxyLH(-), and OxyL(2-) with the experimental observation and detailed analysis, we concluded that the direct decomposition excited-state product of firefly dioxetanone in vivo and the only light emitter of firefly in natural bioluminescence is the first singlet excited state (S1) of phenolate-keto-OxyLH(-).

18.
J Phys Chem B ; 114(44): 14096-102, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20961081

RESUMO

The (6-4) photoproduct ((6-4) PP) is one of the main lesions in UV-induced DNA damage. The (6-4) PP and its valence isomer Dewar photoproduct (Dewar PP) can have a great threat of mutation and cancer but gained much less attention to date. In this study, with density functional theory (DFT) and the complete active space self-consistent field (CASSCF) methods, the photoisomerization processes between the (6-4) PP and the Dewar PP in the gas phase, the aqueous solution, and the photolyase have been carefully examined. Noticeably, the solvent effect is treated with the CASPT2//CASSCF/Amber (QM/MM) method. Our calculations show that the conical intersection (CI) points play a crucial role in the photoisomerization reaction between the (6-4) PP and the Dewar PP in the gas and the aqueous solution. The ultrafast internal conversion between the S(2) ((1)ππ*) and the S(0) states via a distorted intersection point is found to be responsible for the formation of the Dewar PP lesion at 313 nm, as observed experimentally. For the reversed isomeric process, two channels involving the "dark" excited states have been identified. In addition to the above passages, in the photolyase, a new electron-injection isomerization process as an efficient way for the photorepair of the Dewar PP is revealed.


Assuntos
Dano ao DNA , DNA/química , DNA/genética , Processos Fotoquímicos , Teoria Quântica , DNA/metabolismo , Desoxirribodipirimidina Fotoliase/metabolismo , Gases/química , Isomerismo , Modelos Moleculares , Conformação de Ácido Nucleico , Solventes/química , Termodinâmica
19.
Biomed Environ Sci ; 23(1): 37-41, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20486434

RESUMO

OBJECTIVE: Total cholesterol (TC) is an important risk factor for myocardial infarction (MI), but the effect of TC on MI in Chinese male hypertension population has not been well documented. We conducted a prospective cohort study to determine the incidence and relative risk for MI across a wide range of TC levels in Chinese male hypertension population. METHODS: A cohort of 5298 male employees aged 18-74 years recruited from Capital Steel and Iron Company in Beijing of China in 1974-1980 was followed up for an average of 20.84 years. A total of 122 incident MI cases were identified during the period of follow-up. RESULTS: The incidence of MI among participants with elevated TC and those with desirable TC in male non-hypertension population was 137.20 and 63.81 per 100,000 person-years, respectively; and the corresponding incidence in male hypertension population was 279.80 and 130.96 per 100,000 person-years, respectively. After adjustment for important covariables, 10.38%, 16.71%, and 23.80% of MI cases were attributable to hypertension, elevated TC, and hypertension plus elevated TC, respectively. In male hypertension population, the multivariate adjusted hazard ratios of MI were 1.21, 2.39, 3.38, and 3.95 for participants with TC level of 5.17-5.68, 5.69-6.20, 6.21-6.71, and > or = 6.72 mmol/L, compared with those with TC < 5.17 mmol/L. The corresponding population attributable risks were 2.92%, 9.20%, 8.87%, and 9.84%, respectively. CONCLUSION: Elevated TC is an important independent risk factor of MI both in male non-hypertension and hypertension populations. There is a linear association between TC level and MI incidence in Chinese male hypertension population.


Assuntos
Colesterol/sangue , Hipertensão/sangue , Hipertensão/complicações , Infarto do Miocárdio/sangue , Infarto do Miocárdio/complicações , Adolescente , Adulto , Idoso , China/epidemiologia , Humanos , Hipertensão/epidemiologia , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Modelos de Riscos Proporcionais , Fatores de Risco , Adulto Jovem
20.
J Chem Phys ; 131(12): 124304, 2009 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-19791878

RESUMO

In concert with the latest experiment of velocity imaging technique [X. P. Zhang et al., ChemPhysChem 9, 1130 (2008)], quantum chemical calculations with relativistic effect were performed on the photodissociation of bromobenzene (BrPh) and iodobenzene (IPh) at 266 nm. The method of multistate second order multiconfigurational perturbation theory in conjunction with spin-orbit interaction through complete active space state interaction was employed to calculate the potential energy curves for the ground and low-lying excited states of BrPh and IPh along their photodissociation reaction coordinates. The dissociation mechanisms with products of X((2)P(3/2)) and X(*)((2)P(1/2)) (X = Br,I) states were clarified.

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