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1.
Lett Appl Microbiol ; 74(3): 385-394, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34825719

RESUMO

Here we studied at a laboratory scale a potential strategy to revalorize the residual rice remaining at the end of a conventional conidia production process in solid-state culture. The conidia production of Trichoderma asperellum Th-T4 (3) and Metarhizium robertsii Xoch-8.1 started with the use of fresh rice (unrecycled rice) as the substrate (cycle one), and continued with the use of recycled rice in successive cycles of conidia production. The rice remaining at the end of the first cycle was reused without any further sterilization or reinoculation. As a result, it was observed that the conidia production and productivity significantly increased in both fungi. Conidia production in T. asperellum Th-T4 (3) increased from 1 × 109 (first cycle) to 2·9 × 109 conidia per gram of initial dry substrate (con⋅gds-1 ) (second cycle using recycled rice), while in M. robertsii Xoch-8.1, this parameter increased form 5·7 × 108 to 1·4 × 109 con⋅gds-1 . Both fungi grew faster and conidiated earlier when recycled rice was used as the substrate, therefore, conidia productivity was also significantly improved. Furthermore, the use of recycled rice did not affect conidia viability. This is the first report about a recycling methodology completely free of extra-processing steps, and useful to increase conidia production and productivity.


Assuntos
Metarhizium , Oryza , Fermentação , Esporos Fúngicos
2.
J Microsc ; 252(1): 58-70, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23889193

RESUMO

We present an integrated light-electron microscope in which an inverted high-NA objective lens is positioned inside a scanning electron microscope (SEM). The SEM objective lens and the light objective lens have a common axis and focal plane, allowing high-resolution optical microscopy and scanning electron microscopy on the same area of a sample simultaneously. Components for light illumination and detection can be mounted outside the vacuum, enabling flexibility in the construction of the light microscope. The light objective lens can be positioned underneath the SEM objective lens during operation for sub-10 µm alignment of the fields of view of the light and electron microscopes. We demonstrate in situ epifluorescence microscopy in the SEM with a numerical aperture of 1.4 using vacuum-compatible immersion oil. For a 40-nm-diameter fluorescent polymer nanoparticle, an intensity profile with a FWHM of 380 nm is measured whereas the SEM performance is uncompromised. The integrated instrument may offer new possibilities for correlative light and electron microscopy in the life sciences as well as in physics and chemistry.


Assuntos
Microscopia/instrumentação , Microscopia/métodos , Linhagem Celular , Chrysanthemum , Células Epiteliais/citologia , Células Epiteliais/ultraestrutura , Humanos , Pólen/citologia , Pólen/ultraestrutura
3.
Artigo em Inglês | MEDLINE | ID: mdl-34690105

RESUMO

INTRODUCTION AND AIMS: Fibrosis staging in patients with nonalcoholic fatty liver disease (NAFLD) is carried out through the application of stepwise algorithms but there is little real-world data on their use. Our aim was to calculate the number of patients with NAFLD and indeterminate or high risk for fibrosis, assessed through noninvasive scores, that consequently underwent further staging evaluation. MATERIALS AND METHODS: A cross-sectional multicenter cohort study was conducted on patients with NAFLD evaluated by hepatologists within the time frame of June 1 and July 31, 2018. The FIB-4 and NAFLD fibrosis scores were calculated in all the patients, and if at least one of the scores suggested indeterminate or high risk for fibrosis, we believed the patient should have undergone additional fibrosis staging assessment. RESULTS: The study included 238 patients. The median time interval from NAFLD diagnosis and inclusion in the analysis was 12.2 months (IQR 3.0-36.5). A total of 128 (54%) patients had at least one noninvasive score that suggested indeterminate or high risk for fibrosis but studies to confirm the fibrosis grade (elastography, biopsy, etc.) were performed on only 72 (56%). The main barriers encountered by the physicians for applying the staging algorithms were related to health insurance coverage and imaging study costs. CONCLUSIONS: A high percentage of patients with NAFLD were at indeterminate or high risk for fibrosis, according to noninvasive scores, but additional studies were carried out on only half of them, showing low adherence to current recommendations.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Algoritmos , Estudos de Coortes , Estudos Transversais , Fibrose , Humanos , Cirrose Hepática
4.
Plant Biol (Stuttg) ; 24(1): 185-191, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34634170

RESUMO

Endemic species distributed in fragmented habitats are highly vulnerable to extinction because they may have low genetic diversity. However, some life-history traits can mitigate the effect of genetic drift on populations. We analysed the level and distribution of genetic variation and ancestral population size of Yucca capensis, a long-lived endemic plant of the Baja California Peninsula, Mexico. Its populations are scattered across a habitat that is suffering accelerated transformation. We used six nuclear microsatellites to genotype 224 individuals from 17 locations across the entire species' geographic range. We estimated polymorphisms, heterozygosity and genetic structure. We also evaluated the ancestral and recent effective size and time since the population started to change. We found high heterozygosity, high polymorphism and low differentiation among locations, suggesting a panmictic population across the range. We also detected a large ancestral effective population size, which suffered a strong reduction in the Mid-Holocene. Despite changes in environmental conditions caused by habitat modification, the high diversity and low differentiation in Y. capensis may result from its large ancestral effective size and life-history traits, such as plant longevity, clonal growth and mating system, which reduce the rate of loss of genetic variation. However, the dependence on a specialist pollinator that displays short flight range can reduce gene flow among the plant populations and could, shortly, lead them into an extinction vortex.


Assuntos
Asparagaceae , Yucca , Ecossistema , Fluxo Gênico , Variação Genética , Genética Populacional , México , Repetições de Microssatélites/genética , Árvores/genética
5.
Hernia ; 25(4): 1-13, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32959176

RESUMO

PURPOSE: The abdominal wall and musculoskeletal tendons share many anatomic, physiologic, and functional characteristics. This review aims to highlight these similar characteristics and to present a rationale why the treatment principles of successful musculoskeletal tendon reconstruction, including principles of surgical technique and physical therapy, can be used in the treatment of complex abdominal wall reconstruction or ventral hernia repair. METHODS: The MEDLINE/PubMed database was used to identify published literature relevant to the purpose of this review. CONCLUSIONS: There are several anatomical and functional similarities between the linea alba and musculoskeletal tendons. Because of this reason, many of the surgical principles for musculoskeletal tendon repair and ventral hernia repair overlap. Distribution of tension is the main driving principle for both procedures. Suture material and configuration are chosen to maximize tension distribution among the tissue edges, as seen in the standard of care multistrand repairs for musculoskeletal tendons, as well as in the small bites for laparotomy technique described in the STITCH trial. Physical therapy is also one of the mainstays of tendon repair, but surprisingly, is not routine in ventral hernia repair. The evidence surrounding physical therapy prehabilitation and rehabilitation protocols in other disciplines is significant. This review challenges the fact that these protocols are not routinely implemented for ventral hernia repair, and presents the rationale and feasibility for the routine practice of physical therapy in ventral hernia repair.


Assuntos
Parede Abdominal , Hérnia Ventral , Parede Abdominal/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia , Humanos , Modalidades de Fisioterapia , Exercício Pré-Operatório , Telas Cirúrgicas , Tendões
6.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33773856

RESUMO

INTRODUCTION AND AIMS: Fibrosis staging in patients with nonalcoholic fatty liver disease (NAFLD) is carried out through the application of stepwise algorithms but there is little real-world data on their use. Our aim was to calculate the number of patients with NAFLD and indeterminate or high risk for fibrosis, assessed through noninvasive scores, that consequently underwent further staging evaluation. MATERIALS AND METHODS: A cross-sectional multicenter cohort study was conducted on patients with NAFLD evaluated by hepatologists within the time frame of June 1 and July 31, 2018. The FIB-4 and NAFLD fibrosis scores were calculated in all the patients, and if at least one of the scores suggested indeterminate or high risk for fibrosis, we believed the patient should have undergone additional fibrosis staging assessment. RESULTS: The study included 238 patients. The median time interval from NAFLD diagnosis and inclusion in the analysis was 12.2months (IQR 3.0-36.5). A total of 128 (54%) patients had at least one noninvasive score that suggested indeterminate or high risk for fibrosis but studies to confirm the fibrosis grade (elastography, biopsy, etc.) were performed on only 72 (56%). The main barriers encountered by the physicians for applying the staging algorithms were related to health insurance coverage and imaging study costs. CONCLUSIONS: A high percentage of patients with NAFLD were at indeterminate or high risk for fibrosis, according to noninvasive scores, but additional studies were carried out on only half of them, showing low adherence to current recommendations.

7.
Acta Ortop Mex ; 33(3): 141-145, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-32246603

RESUMO

OBJECTIVE: Determine the association between clinical characteristics and laboratory studies with the type of isolated microorganism in blood cultures of patients with Pyogenic Spondylodiscitis. MATERIAL AND METHODS: It is a cross-analytical study, clinical records of patients with Pyogenic Spondylodiscitis were reviewed from January 2013 to January 2017. Univariate descriptive analysis was performed using frequencies and percentages for qualitative variables, central trend measures and dispersion for quantitative ones. Bivariate analysis by testing of 2 or Fishers exact test. Analysis of quantitative variables using T Student or Mann-Whitney U. Spearmans correlation coefficient was used. Considering statistical significance p 0.05. RESULTS: A sample of 34 patients was obtained, 20 (58%) were women, median (Me) of age 60 years (52-66). Was isolated into blood cultures, Gram-positive bacteria 11 (32.4%) gram negatives 23 (67.6%). The microorganism most common isolate was Escherichia coli 12 (35.3%). Patients with Gram-negative spondylodiscitis had mild pain and globular sedimentation rate (VSG) Me 26 mm/hra P (18-36), patients with Gram-positive spondylodyscitis had severe pain and VSG Me 38 mm/h P (34-40) (p= 0.000 and 0.028, respectively). VSG and pain in the group of patients with gram-negative bacteria spondylodiscitis had a moderate Spearman correlation coefficient of 0.418, (p = 0.047); in the Gram positives group, a low correlation coefficient of Spearman 0.228, (p = 0.507). CONCLUSION: There is a clinical and statistical association significant between types of isolated microorganism in blood culture, pain intensity valued on analog visual scale (EVA) and VSG levels.


OBJETIVO: Determinar la asociación entre las características clínicas y estudios de laboratorio con el tipo de microorganismo aislado en hemocultivos de pacientes con espondilodiscitis piógena. MATERIAL Y MÉTODOS: Es un estudio transversal analítico, se revisaron expedientes clínicos de pacientes con espondilodiscitis piógena desde Enero de 2013 hasta Enero de 2017. Se realizó análisis descriptivo univariado usando frecuencias y porcentajes para variables cualitativas, medidas de tendencia central y dispersión para las cuantitativas. Análisis bivariado mediante prueba de 2 o test exacto de Fisher. Análisis de variables cuantitativas mediante t Student o U de Mann-Whitney. Se usó coeficiente de correlación de Spearman. Considerando significancia estadística p 0.05. RESULTADOS: Se obtuvo una muestra de 34 pacientes, 20 (58%) fueron mujeres, mediana (Me) de edad 60 años (52-66). Se aisló en hemocultivos, bacterias Gram positivas 11 (32.4%) y Gram negativas 23 (67.6%). El microorganismo aislado más frecuente fue Escherichia coli 12 (35.3%). Los pacientes con espondilodiscitis por Gram negativas presentaron dolor leve y velocidad de sedimentación globular (VSG) Me 26 mm/hra P (18-36), los pacientes con espondilodiscitis por Gram positivas presentaron dolor severo y VSG Me 38 mm/h P (34-40) (p = 0.000 y 0.028, respectivamente). La VSG y dolor en el grupo de pacientes con espondilodiscitis por bacterias Gram negativas tuvo un coeficiente de correlación de Spearman moderado 0.418, (p = 0.047); en el grupo de Gram positivas, un coeficiente de correlación de Spearman bajo 0.228, (p = 0.507). ­. CONCLUSIÓN: Existe una asociación clínica y estadística de manera significativa entre los tipos de microorganismo aislado en hemocultivo, la intensidad del dolor valorado en escala visual análoga (EVA) y los niveles de VSG.


Assuntos
Discite , Dor , Discite/complicações , Discite/etiologia , Discite/terapia , Feminino , Humanos , Estudos Retrospectivos , Resultado do Tratamento
8.
Actas Urol Esp (Engl Ed) ; 42(4): 249-255, 2018 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29395386

RESUMO

INTRODUCTION AND OBJECTIVES: The management of Prostate cancer (PCa) in renal transplant recipients (RTR) is challenging and remain controversial. Currently there is no consensus about this condition. The aim of the study was to analyse our experience in the diagnosis and management of PCa in RTR. METHOD: Retrospective monocentric study of a prospective and consecutive database from 2003-2017. Inclusion of RTR diagnosed of PCa. Staging and treatment in agreement with the contemporary guidelines. The main outcome measures included clinical staging, type of treatment, oncological outcomes and follow-up. RESULTS: 1,330 renal transplants were performed (787 males), diagnosed of PCa in 33 RTR (4.2%), mean age 66years±6.3 (51-78). Median PSA was 8.8ng/ml and PSA ratio 0.19. Mean time between renal transplantation and PCa diagnosis 130months±90 (2-236). TREATMENTS: Radical prostatectomy (RP) (n=22; 66.7%), Radiation therapy (RT) with Androgen deprivation therapy (ADT) (n=7; 21.2%), Active surveillance (n=3; 9.1%), ADT (n=1; 3%). No graft loss neither impaired renal function due to PCa treatment was reported. After RP two patients (9.1%) presented biochemical recurrence treated with RT. Remission of the 100%. Mean follow-up was 61months±37 (6-132). CONCLUSIONS: PCa in renal transplant patients can be managed with the same therapeutic options as in the general population. Active surveillance should also be provided in RTR despite being under immunosuppressive therapy.


Assuntos
Transplante de Rim , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
9.
Actas Urol Esp (Engl Ed) ; 42(5): 316-322, 2018 Jun.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-29500039

RESUMO

OBJECTIVES: To evaluate the effectiveness and safety of simultaneous bilateral percutaneous nephrolithotomy performed in patients affected with bilateral renal calculi. MATERIALS AND METHODS: This is a prospective study from September 2012 to November 2016. Patients diagnosed of bilateral kidney stones with abdominal CT scan were included. Surgical technique prone position, renal puncture guided by fluoroscopy and tract dilation up to 24Ch. We reviewed demographic and stone characteristics, stone free rate, clinical success, complications and follow-up. RESULTS: During the study period, 732 percutaneous nephrolithotomies were performed. Eighteen patients were included (36 renal units, 2.5%), 13 men and 5 women, with a median age of 58 years and an interquartile range (IQR) of 40-66. Median stone burden was 228mm2 (IQR 134-389); median operative time, 150minutes (IQR 97-180); and median hospital stay, 5 days (IQR 5-15). Stone free rate was 80%. Residual calculi were encountered in 8 renal units (22.2%) and required other complementary techniques for their complete tesolution 4 external shockwave lithotripsies, one open ureterolithotomy, 2 ureteroscopies and one second look. Major complications included 4 cases of severe hemorrhage managed with angiographic embolization. The median follow-up was 36 months (range 26-46). CONCLUSIONS: Simultaneous bilateral percutaneous nephrolithotomy is an effective and safe procedure in patients affected with bilateral renal calculi. It is a surgical challenge that should be performed in selected patients and in centers with experience.


Assuntos
Cálculos Renais/cirurgia , Nefrolitotomia Percutânea/métodos , Adulto , Idoso , Feminino , Humanos , Cálculos Renais/patologia , Masculino , Pessoa de Meia-Idade , Nefrolitotomia Percutânea/efeitos adversos , Estudos Prospectivos , Resultado do Tratamento
10.
Biosens Bioelectron ; 12(4): 267-75, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9178512

RESUMO

The effect of two types of carbon pastes and two osmium-based redox mediators on the response of amperometric enzyme electrodes for glucose was examined. A hydrophobic mediator and a hydrophilic cationic mediator were prepared and mixed in a paste that contained either mineral oil as the pasting liquid, or a polycationic electrolyte without oil. It was found that the current densities were increased by a factor of 25 when the oil-based paste was replaced by the hydrophilic one (binder paste, BP) and five- to six-fold when the hydrophilic mediator was used in place of the hydrophobic. The linear range for the glucose oxidase electrodes was extended to concentrations higher than 60 mM. The glucose electrodes were preliminary optimized and their half-life time reached more than 12 h when operated continuously under vigorous stirring when the 'pasting' polyelectrolyte was crosslinked. At a working potential of 400 mV versus the Ag/AgCl saturated electrode, the saturating current densities per geometric surface area were 1.2 mA/cm2 +/- 0.2 (n = 7). These 'binder paste electrodes' are the first reported bulk modified electrodes without hydrophobic pasting liquid or cover membranes, and present an interesting research and application tool.


Assuntos
Técnicas Biossensoriais , Carbono , Eletroquímica , Eletrodos , Glucose Oxidase , Pomadas , Solubilidade , Água/química
11.
Biosens Bioelectron ; 15(1-2): 43-52, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10826642

RESUMO

Reagentless fructose and alcohol biosensors have been produced with a versatile enzyme immobilisation technique which mimics natural interactions and flexibility of living systems. The electrode architecture is built up on electrostatic interactions by the sequential adsorption of redox polyelectrolytes and redox enzymes giving rise to the efficient transformation of substrate fluxes into electrocatalytic currents. All investigated multilayer structures were self-deposited on 3-mercapto-1-propanesulfonic acid monolayers self-assembled on gold electrodes. Fructose dehydrogenase, horseradish peroxidase (HRP) and the couple HRP-alcohol oxidase were electrochemically connected with a cationic poly[(vinylpyridine)Os(bpy)2Cl] redox polymer (RP) interface in a layer-by-layer self-deposited architecture. The dependence of the distance on the electrochemical response of this interface was also studied showing a clear decrease in the Faradaic current when the distance to the electrode surface was increased. The sensitivities obtained for each biosensor were 19.3, 58.1 and 10.6 mA M(-1) cm(-1) for fructose, H2O2 and methanol, respectively. The sensitivity values can be easily controlled by a rational deposition and manipulation of the charge in the catalytic layers. The electrostatic assembly of the electrochemical interface and the catalytic layers resulted in integrated biochemical systems in which mass transfer diffusion and heterogeneous catalytic and electron transfer steps are efficiently coupled and can be easily manipulated.


Assuntos
Técnicas Biossensoriais , Oxirredutases do Álcool/metabolismo , Eletroquímica , Frutose/análise , Peroxidase do Rábano Silvestre , Peróxido de Hidrogênio/análise , Indicadores e Reagentes , Metanol/análise , Oxirredução
12.
Acta Orthop Belg ; 64(1): 100-3, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9586259

RESUMO

The case of an old volar dislocation of the lunate, associated with median nerve neuropathy, is described in a 37-year-old patient. The treatment took into account the age of the patient and the relative tolerance to the dislocation. We performed a simple excision of the lunate combined with a release of the transverse carpal ligament in order to free the median nerve, together with a tenosynovectomy of flexor digitorum profoundus. Two years after operation, wrist function was virtually complete and the patient was asymptomatic and had resumed his occupation.


Assuntos
Síndrome do Túnel Carpal/etiologia , Luxações Articulares/complicações , Osso Semilunar/lesões , Traumatismos do Punho/complicações , Adulto , Fatores Etários , Seguimentos , Humanos , Luxações Articulares/cirurgia , Ligamentos Articulares/cirurgia , Osso Semilunar/cirurgia , Masculino , Nervo Mediano/cirurgia , Sinovectomia , Tendões/cirurgia , Articulação do Punho/fisiologia
13.
J Pharm Belg ; 48(5): 357-64, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8120788

RESUMO

alpha-(p-nitrophenyl)-beta-(1-pyrrolidinyl) propionic acid and its methyl ester were prepared and their structures were assigned by elemental analysis, 1H-NMR and IR spectroscopy. The methyl ester derivative was tested in the following pharmacological assays: 1) Acute toxicity; 2) effect on the cat nictitating membrane; 3) effect on the isolated rat uterus; 4) Cardiovascular effects were studied by experiments on arterial pressure in dogs and cats as well as heart rate; 5) Locomotor activity in mice was explored and 6) The effects on the central nervous system in rabbits was studied by electroencephalography. The results showed that this compound presents alpha and beta adrenergic activity in the experimental preparations studied.


Assuntos
Fenilacetatos/síntese química , Pirrolidinas/síntese química , Simpatomiméticos/síntese química , Animais , Gatos , Sistema Nervoso Central/efeitos dos fármacos , Cães , Feminino , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Fenilacetatos/farmacologia , Fenilacetatos/toxicidade , Pirrolidinas/farmacologia , Pirrolidinas/toxicidade , Coelhos , Ratos , Ratos Wistar , Simpatomiméticos/farmacologia , Simpatomiméticos/toxicidade
14.
Rev Biol Trop ; 47(1-2): 245-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10834084

RESUMO

Fecal bile acid patterns have been used successfully to identify scats. Neotropical felid scats are capable of this biochemical identification because they present low concentrations of plant pigments that would interfere in fecal bile acids detection. However, neotropical felid scats have poor quantities of bile acids, so we developed in this work a proper technique for their extraction, visualization and determination. Twenty eighth feces of seven different felid species, collected from Zoological and Wildlife Parks, were dried and pulverized. The procedure for analyzing feces is: Take one g of pulverized feces and shake for 3 hr at room temperature in 20 ml benzene:methanol; filter and evaporate to 5 ml. Spot on TLC plate and develop in toluene:acetic acid:water. Dry and visualize with anisaldehyde. Field collected scats could be identified by the bile acids pattern revealed by this specific technique and, then, used as a source of information for distribution, density and food habits studies.


Assuntos
Ácidos e Sais Biliares/análise , Carnívoros , Cromatografia em Camada Fina/métodos , Fezes/química , Animais , Meio Ambiente
15.
J Glob Infect Dis ; 3(2): 189-94, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21731309

RESUMO

This report analyses the trends in the cholera epidemic that hit Ecuador in 1991. The study is based on personal experiences and analysis of epidemiological databases from the Ministry of Public Health of Ecuador. The number of cases and initial attack rates in an immunologically naive population are described by province. An analysis of the Andean and coastal cholera patterns of transmission are described along with its associated risk factors. The logistical, environmental, and socio-cultural risk factors prevalent during the epidemic and the control measures implemented are also reviewed. Also, the role of the epidemic in the development of the public health and healthcare resources in Ecuador is discussed here. Current data indicate favorable conditions for another outbreak of cholera in Ecuador. In view of the existing risk factors, new strategies are proposed to prevent such an epidemic in the future.

18.
Arthritis Rheum ; 56(4): 1242-50, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17393453

RESUMO

OBJECTIVE: To define the cytokine and chemokine profile in cerebrospinal fluid (CSF) from patients with neuropsychiatric systemic lupus erythematosus (NPSLE). METHODS: Forty-two SLE patients who had been hospitalized because of NP manifestations were studied. Patients were evaluated at hospitalization and 6 months later; a CSF sample was obtained at each evaluation. As controls, CSF from 6 SLE patients with septic meningitis, 16 SLE patients with no history of NP manifestations (non-NPSLE), and 25 patients with nonautoimmune diseases were also studied. Soluble molecules, including cytokines (interleukin-2 [IL-2], IL-4, IL-6, IL-10, tumor necrosis factor alpha [TNFalpha], and interferon-gamma [IFNgamma]) and chemokines (monocyte chemotactic protein 1 [MCP-1], RANTES, IL-8, monokine induced by IFNgamma [MIG], and interferon-gamma-inducible 10-kd protein [IP-10]), were measured with the use of cytometric bead array kits. RESULTS: CSF levels of the following molecules were significantly increased in NPSLE patients as compared with non-NPSLE and nonautoimmune diseases control patients, respectively: IL-6 (32.7 versus 3.0 and 2.96 pg/ml), IL-8 (102.8 versus 29.97 and 19.7 pg/ml), IP-10 (888.2 versus 329.7 [P not significant] and 133.6 pg/ml), RANTES (3.8 versus 2.5 and 2.2 pg/ml), MCP-1 (401.7 versus 257.9 [P not significant] and 136.9 pg/ml), and MIG (35.4 versus 11.4 and 3.5 pg/ml). Low levels of IL-2, IL-4, IL-10, TNFalpha, and IFNgamma were found in all groups. All cytokines and chemokines, except TNFalpha, were significantly higher among the SLE patients with septic meningitis than among the NPSLE patients. Six months later and in the absence of NP manifestations, all elevated molecule levels, except RANTES, in patients with NPSLE had decreased significantly, and no differences were noted between the NPSLE and non-NPSLE groups. CONCLUSION: A central nervous system response composed of IL-6 and chemokines, but not Th1/Th2 cytokines, is associated with NP manifestations in SLE patients.


Assuntos
Quimiocinas/líquido cefalorraquidiano , Interleucina-6/líquido cefalorraquidiano , Vasculite Associada ao Lúpus do Sistema Nervoso Central/líquido cefalorraquidiano , Vasculite Associada ao Lúpus do Sistema Nervoso Central/psicologia , Adulto , Citocinas/líquido cefalorraquidiano , Feminino , Humanos , Lúpus Eritematoso Sistêmico , Vasculite Associada ao Lúpus do Sistema Nervoso Central/diagnóstico , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Índice de Gravidade de Doença
19.
Proc Natl Acad Sci U S A ; 103(26): 9850-4, 2006 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-16777966

RESUMO

Ribonucleotide reductase (RNR) from Chlamydia trachomatis is a class I RNR composed of proteins R1 and R2. In protein R2, the tyrosine residue harboring the radical that is necessary for catalysis in other class I RNRs is replaced by a phenylalanine. Active C. trachomatis RNR instead uses the Fe(III)-Fe(IV) state of the iron cluster in R2 as an initiator of catalysis. The paramagnetic Fe(III)-Fe(IV) state, identified by (57)Fe substitution, becomes electron spin resonance detectable in samples that are frozen during conditions of ongoing catalysis. Its amount depends on the conditions for catalysis, such as incubation temperature and the R1/R2 ratio. The results link induction of the Fe(III)-Fe(IV) state with enzyme activity of chlamydial RNR. Based on these observations, a reaction scheme is proposed for the iron site. This scheme includes (i) an activation cycle involving reduction and an oxygen reaction in R2 and (ii) a catalysis cycle involving substrate binding and turnover in R1.


Assuntos
Proteínas de Bactérias/química , Chlamydia trachomatis/enzimologia , Ferro/química , Ribonucleotídeo Redutases/química , Tirosina/química , Catálise , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Oxirredução
20.
Biochemistry ; 42(45): 13280-6, 2003 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-14609339

RESUMO

Reaction centers from the Y(L167) mutant of Rhodobacter sphaeroides, containing a highly oxidizing bacteriochlorophyll dimer and a tyrosine residue substituted at Phe L167, were compared to reaction centers from the Y(M) mutant, with a tyrosine at M164, and a quadruple mutant containing a highly oxidizing dimer but no nearby tyrosine residue. Distinctive features in the light-induced optical and EPR spectra showed that the oxidized bacteriochlorophyll dimer was reduced by Tyr L167 in the Y(L167) mutant, resulting in a tyrosyl radical, as has been found for Tyr M164 in the Y(M) mutant. In the Y(L167) mutant, the net proton uptake after formation of the tyrosyl radical and the reduced primary quinone ranged from +0.1 to +0.3 H(+)/reaction center between pH 6 and pH 10, with a dependence that is similar to the quadruple mutant but different than the large proton release observed in the Y(M) mutant. In the light-induced absorption spectrum in the 700-1000 nm region, the Y(L167) mutant exhibited unique changes that can be assigned as arising primarily from an approximately 30 nm blue shift of the dimer absorption band. The optical signals in the Y(L167) mutant were pH dependent, with a pK(a) value of approximately 8.7, indicating that the tyrosyl radical is stabilized at high pH. The results are modeled by assuming that the phenolic proton of Tyr L167 is trapped in the protein after oxidation of the tyrosine, resulting in electrostatic interactions with the tetrapyrroles and nearby residues.


Assuntos
Complexo de Proteínas do Centro de Reação Fotossintética/química , Prótons , Rhodobacter sphaeroides/química , Tirosina/análogos & derivados , Tirosina/química , Substituição de Aminoácidos/genética , Bacterioclorofilas/química , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Histidina/genética , Concentração de Íons de Hidrogênio , Leucina/genética , Luz , Modelos Químicos , Mutagênese Sítio-Dirigida , Oxirredução , Fenilalanina/genética , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Espectrofotometria , Tirosina/genética , Tirosina/metabolismo
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