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1.
Acta Neurol Scand ; 134(2): 154-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26503595

RESUMO

OBJECTIVE: Evidence suggests that intima-media thickness (IMT) and plasma homocysteine (Hcy) levels are associated with one another, and both appear to be related to cognitive dysfunction. However, no connection between both factors taken together and mild cognitive impairment (MCI) has been established. This study analysed potential relationships between IMT, Hcy and MCI. METHODS: We included 105 patients with MCI and 76 controls with no history of vascular disease. All participants underwent laboratory analyses, a carotid ultrasound, and clinical and neuropsychological assessment. We used the Mantel-Haenszel test (MHT), ANCOVA and multiple linear regression models (MLRM) to examine any associations between IMT, Hcy and cognitive state. RESULTS: The MHT revealed a significant association between IMT and risk of MCI (z = 4.285, P < 0.0001). The OR for the upper quartile vs the lower quartile was 5.12 (95% CI: 2.12-12.36). MHT also showed a clear association between Hcy levels and risk of MCI (z = 3.01, P = 0.003). OR for the upper vs the lower quartile was 3.39 (95% CI: 1.41-8.12). Additionally, we found a correlation between IMT and Hcy (r = 0.162, P = 0.032). CONCLUSIONS: Our results suggest that there is a connection between IMT, Hcy levels and presence of amnestic MCI in a population with no history of clinically manifest atherosclerosis. Furthermore, there is also a connection between the IMT and Hcy levels themselves.


Assuntos
Doenças das Artérias Carótidas/epidemiologia , Espessura Intima-Media Carotídea , Disfunção Cognitiva/epidemiologia , Homocisteína/sangue , Idoso , Idoso de 80 Anos ou mais , Doenças das Artérias Carótidas/patologia , Estudos de Casos e Controles , Disfunção Cognitiva/sangue , Disfunção Cognitiva/patologia , Feminino , Humanos , Masculino
3.
Eur Spine J ; 20(9): 1417-26, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21336970

RESUMO

In cervical multi-level degenerative pathology, considering the morbidity of the extensive fusion techniques, some authors advocate for the multilevel disc replacement. This study compared the safety and efficacy of disc replacement with an unconstrained prosthesis in multi- versus single-level patients. A total of 231 patients with cervical degenerative disc disease (DDD) who were treated with cervical disc replacement and completed their 24 months follow-up were analyzed prospectively: 175 were treated at one level, 56 at 2 levels or more. Comparison between both groups was based on usual clinical and radiological outcomes [Neck Disability Index (NDI), Visual Analog Scale (VAS), Range of Motion, satisfaction]. Safety assessments, including complication and subsequent surgeries, were also documented and compared. Mean NDI and VAS scores for neck and arm pain were improved in both groups similarly. Improvement of mobility at treated segments was also similar. Nevertheless, in the multi-level group, analgesic use was significantly higher and occurrence of Heterotopic Ossification significantly lower than in the single-level group. Subject satisfaction was nearly equal, as 94.2% of single-level group patients would undergo the surgery again versus 94.5% in the multi-level group. The overall success rate did not differ significantly. Multi-level DDD is a challenging indication in the cervical spine. This study showed no major significant clinical difference between the two groups. We need further studies to know more about the impact of multi-level arthroplasty, especially on the adjacent segments, but these results demonstrate initial safety and effectiveness in this patient sample.


Assuntos
Vértebras Cervicais/cirurgia , Degeneração do Disco Intervertebral/cirurgia , Substituição Total de Disco/métodos , Adulto , Vértebras Cervicais/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Fusão Vertebral/métodos , Resultado do Tratamento
6.
Eur Spine J ; 18(6): 841-50, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19434431

RESUMO

The interest in cervical total disc replacement (TDR) as an alternative to the so-far gold standard in the surgical treatment of degenerative disc disease (DDD), e.g anterior cervical discectomy and fusion (ACDF), is growing very rapidly. Many authors have established the fact that ACDF may result in progressive degeneration in adjacent segments. On the contrary, but still theoretically, preservation of motion with TDR at the surgically treated level may potentially reduce the occurrence of adjacent-level degeneration (ALD). The authors report the intermediate results of an undergoing multicentre prospective study of TDR with Mobi-C prosthesis. The aim of the study was to assess the safety and efficacy of the device in the treatment of DDD and secondary to evaluate the radiological status of adjacent levels and the occurrence of ossifications, at 2-year follow-up (FU). 76 patients have performed their 2-year FU visit and have been analyzed clinically and radiologically. Clinical outcomes (NDI, VAS, SF-36) and ROM measurements were analyzed pre-operatively and at the different post-operative time-points. Complications and re-operations were also assessed. Occurrences of heterotopic ossifications (HOs) and of adjacent disc degeneration radiographic changes have been analyzed from 2-year FU X-rays. The mean NDI and VAS scores for arm and neck are reduced significantly at each post-operative time-point compared to pre-operative condition. Motion is preserved over the time at index levels (mean ROM = 9 degrees at 2 years) and 85.5% of the segments are mobile at 2 years. HOs are responsible for the fusion of 6/76 levels at 2 years. However, presence of HO does not alter the clinical outcomes. The occurrence rate of radiological signs of ALD is very low at 2 years (9.1%). There has been no subsidence, no expulsion and no sub-luxation of the implant. Finally, after 2 years, 91% of the patients assume that they would undergo the procedure again. These intermediate results of TDR with Mobi-C are very encouraging and seem to confirm the efficacy and the safety of the device. Regarding the preservation of the status of the adjacent levels, the results of this unconstrained device are encouraging, but longer FU studies are needed to prove it.


Assuntos
Artroplastia/métodos , Discotomia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Próteses e Implantes/estatística & dados numéricos , Espondilose/cirurgia , Adulto , Idoso , Artroplastia/efeitos adversos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/patologia , Vértebras Cervicais/cirurgia , Progressão da Doença , Discotomia/efeitos adversos , Feminino , Seguimentos , Humanos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/patologia , Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/patologia , Masculino , Pessoa de Meia-Idade , Cervicalgia/cirurgia , Ossificação Heterotópica/epidemiologia , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Estudos Prospectivos , Próteses e Implantes/efeitos adversos , Radiografia , Espondilose/diagnóstico por imagem , Espondilose/patologia , Tempo , Resultado do Tratamento
7.
Neurochirurgie ; 55(2): 282-90, 2009 Apr.
Artigo em Francês | MEDLINE | ID: mdl-19328504

RESUMO

We report the results of an investigation carried out on the activity of functional neurosurgery of the cranial nerves in the French-speaking countries, based on the analysis of a questionnaire addressed to all the members of the SNCLF. Eighteen centers responded to this questionnaire, which showed that activities and indications varied greatly from one unit to another. The results appear homogeneous and comparable with those reported in the literature. The questionnaire sought to provide a global perspective, open to the comments and questions of all responders on the various techniques raised, with the objective of establishing a common decisional tree for these pathologies and providing if possible to a consensus for better dissemination of these therapies.


Assuntos
Doenças dos Nervos Cranianos/patologia , Doenças dos Nervos Cranianos/cirurgia , Nervos Cranianos/patologia , Nervos Cranianos/cirurgia , Neurocirurgia/estatística & dados numéricos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Coleta de Dados , Espasmo Hemifacial/cirurgia , Humanos , Inquéritos e Questionários , Neuralgia do Trigêmeo/cirurgia
9.
Semergen ; 44(2): 82-89, 2018 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-28209453

RESUMO

INTRODUCTION: Chronic kidney disease (CKD) is a public health problem, and Primary Care (PC) plays a key role in its detection and classification based on estimated glomerular filtration rate (eGFR), as well as the level of albuminuria for its proper management. The aim of this study was to analyse the prevalence and classification of CKD in patients attended in PC. MATERIAL AND METHODS: An analysis was made of CKD prevalence and classification according to the Kidney Disease-Improving Global Outcomes guidelines in PC patients. All biochemical analyses requested from PC on patients 18 years and older over a 5-year period were collected. When several analyses were available on a patient, the biochemistry result with the best eGFR was selected. RESULTS: Between 2010 and 2014, PC requested 304,523 biochemical analyses on 97,470 adult patients, with a mean age of 53.4±19.4 years, of which 57.2% were women. CKD prevalence was 7.6%. Urine protein results were present in only 16.6% of analyses, and only 15.2% patients had a urine protein result. Urine albumin was measured 15.4% of biochemical controls with eGFR≥60mL/min/1.73m2, in 27.1% of patients with eGFR between 30-59mL/min/1.73m2 (G3a-3b stages), and in 23.4% of patients with eGFR<30mL/min/1.73m2 (G4-5 stages). Urine albumin was tested in 37.7% of diabetics and in 23.5% of impaired fasting glucose. CONCLUSIONS: Requests for the measurement of urine proteins/albumin in PC patients are low, leading to only one in 6 PC patients being classified correctly. The measurement of urine proteins/albumin is higher in CKD and diabetic patients.


Assuntos
Albuminúria/etiologia , Taxa de Filtração Glomerular , Atenção Primária à Saúde , Insuficiência Renal Crônica/diagnóstico , Adulto , Idoso , Albuminúria/epidemiologia , Diabetes Mellitus/epidemiologia , Feminino , Intolerância à Glucose/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Prevalência , Proteinúria/epidemiologia , Proteinúria/etiologia , Insuficiência Renal Crônica/classificação , Insuficiência Renal Crônica/epidemiologia
10.
Methods Enzymol ; 587: 257-269, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28253960

RESUMO

Autophagy is the major cellular process of degradation and is modulated by several signaling pathways. Phosphatidylinositol 3-kinase (PtdIns3K) class III (Vps34) and PtdIns3K class I regulate the autophagy pathway positively and negatively, respectively. Both classes of PtdIns3K participate in the synthesis of phosphatidylinositol 3-phosphate (PtdIns3P), which plays a crucial role in autophagosome biogenesis and membrane traffic. PtdIns3P is a membrane phospholipid that is associated with endogenous FYVE domain-containing proteins. Indeed, such interactions facilitate autophagosome fusion with lysosomes and subsequent cargo degradation. During starvation-induced autophagy, the expression of FYVE domain-containing proteins increases, and their binding to PtdIns3P is strengthened. Nonetheless, not all FYVE domain proteins are related to the induction of autophagy. This method report presents the quantification of PtdIns3P synthesis by using cells either transiently transfected with or stably expressing FYVE-dsRed.


Assuntos
Autofagia , Microscopia de Fluorescência/métodos , Biologia Molecular/métodos , Fosfatos de Fosfatidilinositol/biossíntese , Proteínas Recombinantes/metabolismo , Linhagem Celular , Corantes Fluorescentes/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Fosfatos de Fosfatidilinositol/análise , Proteínas Recombinantes/análise , Proteínas Recombinantes/genética
11.
Methods Enzymol ; 587: 55-70, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28253976

RESUMO

Macroautophagy (usually referred to as autophagy) is the most important degradation system in mammalian cells. It is responsible for the elimination of protein aggregates, organelles, and other cellular content. During autophagy, these materials (i.e., cargo) must be engulfed by a double-membrane structure called an autophagosome, which delivers the cargo to the lysosome to complete its degradation. Autophagy is a very dynamic pathway called autophagic flux. The process involves all the steps that are implicated in cargo degradation from autophagosome formation. There are several techniques to monitor autophagic flux. Among them, the method most used experimentally to assess autophagy is the detection of LC3 protein processing and p62 degradation by Western blotting. In this chapter, we provide a detailed and straightforward protocol for this purpose in cultured mammalian cells, including a brief set of notes concerning problems associated with the Western-blotting detection of LC3 and p62.


Assuntos
Autofagia/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Biologia Molecular/métodos , Animais , Western Blotting , Células Cultivadas , Eletroforese/métodos , Fibroblastos/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/análise , Proteína Sequestossoma-1/metabolismo
12.
Mol Neurobiol ; 54(8): 6287-6303, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27714635

RESUMO

Mitochondria-associated membranes (MAMs) are structures that regulate physiological functions between endoplasmic reticulum (ER) and mitochondria in order to maintain calcium signaling and mitochondrial biogenesis. Several proteins located in MAMs, including those encoded by PARK genes and some of neurodegeneration-related proteins (huntingtin, presenilin, etc.), ensure this regulation. In this regard, MAM alteration is associated with neurodegenerative diseases such as Parkinson's (PD), Alzheimer's (AD), and Huntington's diseases (HD) and contributes to the appearance of the pathogenesis features, i.e., autophagy dysregulation, mitochondrial dysfunction, oxidative stress, and lately, neuronal death. Moreover,, ER stress and/or damaged mitochondria can be the cause of these disruptions. Therefore, ER-mitochondria contact structure and function are crucial to multiple cellular processes. This review is focused on the molecular interaction between ER and mitochondria indispensable to MAM formation and on MAM alteration-induced etiology of neurodegenerative diseases.


Assuntos
Morte Celular/fisiologia , Retículo Endoplasmático/metabolismo , Membranas Mitocondriais/metabolismo , Estresse Oxidativo/fisiologia , Doença de Parkinson/metabolismo , Animais , Humanos , Mitocôndrias/metabolismo , Biogênese de Organelas
13.
Surg Endosc ; 20(9): 1482-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16865628

RESUMO

BACKGROUND: Carbon dioxide (CO2) pneumoperitoneum has been shown to attenuate the inflammatory response after laparoscopy. This study tested the hypothesis that abdominal insufflation with CO2 improves survival in an animal model of sepsis and investigated the associated mechanism. METHODS: The effect of CO2, helium, and air pneumoperitoneum on mortality was studied by inducing sepsis in 143 rats via intravenous injection of lipopolysaccharide (LPS). To test the protective effect of CO2 in the setting of a laparotomy, an additional 65 animals were subjected to CO2 pneumoperitoneum, helium pneumoperitoneum, or the control condition after laparotomy and intraperitoneal LPS injection. The mechanism of CO2 protection was investigated in another 84 animals. Statistical significance was determined via Kaplan-Meier analysis for survival and analysis of variance (ANOVA) for serum cytokines. RESULTS: Among rats with LPS-induced sepsis, CO2 pneumoperitoneum increased survival to 78%, as compared with using helium pneumoperitoneum (52%; p < 0.05), air pneumoperitoneum (55%; p = 0.09), anesthesia control (50%; p < 0.05), and LPS-only control (42%; p < 0.01). Carbon dioxide insufflation also significantly increased survival over the control condition (85% vs 25%; p < 0.05) among laparotomized septic animals, whereas helium insufflation did not (65% survival). Carbon dioxide insufflation increased plasma interleukin-10 (IL-10) levels by 35% compared with helium pneumoperitoneum (p < 0.05), and by 34% compared with anesthesia control (p < 0.05) 90 min after LPS stimulation. Carbon dioxide pneumoperitoneum resulted in a threefold reduction in tumor necrosis factor-alpha (TNF-alpha) compared with helium pneumoperitoneum (p < 0.05), and a sixfold reduction with anesthesia control (p < 0.001). CONCLUSION: Abdominal insufflation with CO2, but not helium or air, significantly reduces mortality among animals with LPS-induced sepsis. Furthermore, CO2 pneumoperitoneum rescues animals from abdominal sepsis after a laparotomy. Because IL-10 is known to downregulate TNF-alpha, the increase in IL-10 and the decrease in TNF-alpha found among the CO2-insufflated animals in our study provide evidence for a mechanism whereby CO2 pneumoperitoneum reduces mortality via IL-10-mediated downregulation of TNF-alpha.


Assuntos
Dióxido de Carbono , Pneumoperitônio Artificial , Sepse/mortalidade , Abdome/microbiologia , Animais , Regulação para Baixo , Interleucina-10/metabolismo , Laparotomia/efeitos adversos , Lipopolissacarídeos , Masculino , Ratos , Ratos Sprague-Dawley , Terapia de Salvação , Sepse/induzido quimicamente , Sepse/etiologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/antagonistas & inibidores
14.
Surg Endosc ; 20(8): 1225-32, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16865627

RESUMO

BACKGROUND: Laparoscopic surgery preserves the immune system and has anti-inflammatory properties. CO2 pneumoperitoneum attenuates lipopolysaccharide (LPS)-induced cytokine production and increases survival. We tested the hypothesis that CO2 pneumoperitoneum mediates its immunomodulatory properties via stimulation of the cholinergic pathway. METHODS: In the first experiment, rats (n = 68) received atropine 1 mg/kg or saline injection 10 min prior to LPS injection and were randomization into four 30-min treatment subgroups: LPS only control, anesthesia control, CO2 pneumoperitoneum, and helium pneumoperitoneum. In a second experiment, rats (n = 40) received atropine 2 mg/kg or saline 10 min prior to randomization into the same four subgroups described previously. In a third experiment, rats (n = 96) received atropine 2 mg/kg or saline 10 min prior to randomization into eight 30-min treatment subgroups followed by LPS injection: LPS only control; anesthesia control; and CO2 or helium pneumoperitoneum at 4, 8, and 12 mmHg. In a fourth experiment, rats (n = 58) were subjected to bilateral subdiaphragmatic truncal vagotomy or sham operation. Two weeks postoperatively, animals were randomized into four 30-min treatment subgroups followed by LPS injection: LPS only control, anesthesia control, CO2 pneumoperitoneum, and helium pneumoperitoneum. Blood samples were collected from all animals 1.5 h after LPS injection, and cytokine levels were determined by enzyme-linked immunosorbent assay. RESULTS: Serum tumor necrosis factor-alpha (TNF-alpha) levels were consistently suppressed among the saline-CO2 pneumoperitoneum groups compared to saline-LPS only control groups (p < 0.05 for all four experiments). All chemically vagotomized animals had significantly reduced TNF-alpha levels compared to their saline-treated counterparts (p < 0.05 for all), except among the CO2 pneumoperitoneum-treated animals. Increasing insufflation pressure with helium eliminated differences (p < 0.05) in TNF-alpha production between saline- and atropine-treated groups but had no effect among CO2 pneumoperitoneum-treated animals. Finally, vagotomy (whether chemical or surgical) independently decreased LPS-stimulated TNF-alpha production in all four experiments. CONCLUSION: CO2 pneumoperitoneum modulates the immune system independent of the vagus nerve and the cholinergic pathway.


Assuntos
Dióxido de Carbono , Sistema Imunitário/fisiopatologia , Laparoscopia , Sistema Nervoso Parassimpático/fisiopatologia , Pneumoperitônio Artificial , Animais , Atropina/farmacologia , Fibras Colinérgicas , Lipopolissacarídeos/farmacologia , Masculino , Bloqueio Nervoso , Vias Neurais/fisiopatologia , Parassimpatolíticos/farmacologia , Estimulação Física , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Vagotomia , Nervo Vago/efeitos dos fármacos
15.
Curr Med Chem ; 23(21): 2275-85, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27237817

RESUMO

Pompe disease or glycogen storage disease type II (OMIM: 232300) is a lysosomal storage disorder resulting from a partial or total lack of acid alphaglucosidase, which may produce muscle weakness, gait abnormalities, or even death by respiratory failure. In the last decade, autophagy has been proposed as a mechanism involved in the severity of symptoms related to this disorder and as a potential therapeutic target to alleviate disease progression. This review summarizes the relationship between autophagy and Pompe disease, including what information has been recently discovered and what remains unclear.


Assuntos
Autofagia , Doença de Depósito de Glicogênio Tipo II/patologia , Animais , Modelos Animais de Doenças , Terapia de Reposição de Enzimas , Doença de Depósito de Glicogênio Tipo II/metabolismo , Doença de Depósito de Glicogênio Tipo II/terapia , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , alfa-Glucosidases/genética , alfa-Glucosidases/metabolismo
16.
Biochim Biophys Acta ; 1122(1): 99-106, 1992 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-1633201

RESUMO

Binding of NADP to glucose-6-phosphate dehydrogenase (G6PD) from Dicentrarchus labrax liver has stabilized its native structure against thermal inactivation, guanidine hydrochloride unfolding and inactivation by tryptic digestion. The time-course of G6PD inactivation by guanidine hydrochloride in the presence of NADP has provided experimental evidence in favor of a conformational drift upon NADP binding to the bass enzyme. Based on the inactivation patterns obtained when the enzyme was treated with guanidine hydrochloride and trypsin, it is proposed that the enzyme conformation induced upon NADP binding is in slow equilibrium with the conformation stabilized in the absence of NADP. FPLC studies have shown that micromolar concentrations of NADP induced oligomerization of G6PD. In addition, the different K0.5 values of NADP binding to the enzyme, ranging from 1-2 microM (from trypsin inactivation) to 90 microM (from titration of the intrinsic fluorescence), suggest a step-wise binding of NADP to the oligomer, with negative cooperativity in the saturation process.


Assuntos
Glucosefosfato Desidrogenase/metabolismo , NADP/metabolismo , Animais , Bass , Ativação Enzimática/efeitos dos fármacos , Glucosefosfato Desidrogenase/química , Guanidina , Guanidinas/farmacologia , Temperatura Alta , Cinética , Fígado/enzimologia , Conformação Proteica , Desnaturação Proteica , Espectrometria de Fluorescência , Tripsina
17.
Biochim Biophys Acta ; 1476(2): 181-90, 2000 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-10669784

RESUMO

Arginase I is a homotrimeric protein with a binuclear manganese cluster. At the C-terminus of each monomer, the polypeptide chain forms an unusual S-shaped oligomerization motif where the majority of intermonomer contacts are located [Z.F. Kanyo, L.R. Scolnick, D.E. Ash, D.W. Christianson, Nature 383 (1996) 554-557]. In order to study the implication of this motif in the quaternary structure of human arginase I, we have constructed a truncated arginase lacking the 14 C-terminal amino acids, leaving Arg-308 as the last residue in the sequence. The resulting protein retains its trimeric structure, as determined by gel filtration (molecular mass 94 kDa). The same result was obtained in the presence of high ionic strength (KCl 0.5 M). Both data indicate that neither the S-shaped motif nor Arg-308 are fundamental in keeping the trimeric quaternary structure. Data obtained from intrinsic anisotropy and fluorescence intensity studies allow us to predict that the distance between the two unique tryptophans in the sequence is 2.9 nm in the native arginase and 4.1 nm for the truncated mutant. These distances allow us to assume a different conformational state in the truncated arginase without any change in its quaternary structure, suggesting that the carboxy-terminal motif is not the most prominent domain implicated in the quaternary structure of human arginase. Collisional quenching studies reinforce this possibility, since using I(-) as quenching molecule we were able to distinguish the two tryptophans in the truncated arginase. Moreover, kinetic studies show that the truncated mutant was fully active. In summary, the main conclusion about the structure of the human arginase I, derived from our study, is that the C-terminal S-shaped motif is not basic to the maintenance of the quaternary structure nor to the activity of the protein.


Assuntos
Arginase/química , Conformação Proteica , Sequência de Aminoácidos , Humanos , Dados de Sequência Molecular , Mutação , Relação Estrutura-Atividade
18.
Arch Intern Med ; 161(19): 2357-65, 2001 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-11606152

RESUMO

BACKGROUND: Improving obstetric care in resource-limited countries is a major international health priority. OBJECTIVE: To reduce infection rates after cesarean section by optimizing systems of obstetric care for low-income women in Colombia by means of quality improvement methods. METHODS: Multidisciplinary teams in 2 hospitals used simple methods to improve their systems for prescribing and administering perioperative antibiotic prophylaxis. Process indicators were the percentage of women in whom prophylaxis was administered and the percentage of these women in whom it was administered in a timely fashion. The outcome indicator was the surgical site infection rate. RESULTS: Before improvement, prophylaxis was administered to 71% of women in hospital A; 24% received prophylaxis in a timely fashion. Corresponding figures in hospital B were 36% and 50%. Systems improvements included implementing protocols to administer prophylaxis to all women and increasing the availability of the antibiotic in the operating room. These improvements were associated with increases in overall and timely administration of prophylaxis (P<.001) in both hospitals by time series analysis, with adjustment for volume and case mix. After improvement, overall and timely administration of prophylaxis was 95% and 96% in hospital A and 89% and 96% in hospital B. In hospital A, the surgical site infection rate decreased immediately after the improvements (P<.001). In hospital B, the infection rate began a downward trend before the improvements that continued after their implementation (P =.04). CONCLUSION: Simple quality improvement methods can be used to optimize obstetric services and improve outcomes of care in resource-limited settings.


Assuntos
Ampicilina/uso terapêutico , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Cefalosporinas/uso terapêutico , Cefalotina/uso terapêutico , Cesárea/efeitos adversos , Gentamicinas/uso terapêutico , Penicilina G/uso terapêutico , Penicilinas/uso terapêutico , Infecção da Ferida Cirúrgica/tratamento farmacológico , Infecção da Ferida Cirúrgica/prevenção & controle , Gestão da Qualidade Total , Colômbia , Endometrite/tratamento farmacológico , Endometrite/etiologia , Endometrite/prevenção & controle , Feminino , Hospitais Filantrópicos , Humanos , Unidade Hospitalar de Ginecologia e Obstetrícia , Assistência Perioperatória , Pobreza , Gravidez , Indicadores de Qualidade em Assistência à Saúde , Infecção da Ferida Cirúrgica/etiologia
19.
Neuroreport ; 9(18): 4199-203, 1998 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-9926873

RESUMO

Primary cultures of cerebellar granule neurons, maintained in a serum-containing medium, underwent apoptosis when exposed to C2-ceramide, as assessed by mitochondrial reduction of MTT and intranucleosomal DNA fragmentation. After an 18 h exposure to 50 microM C2-ceramide, cell viability decreased by 25-40%. Addition of lithium together with C2-ceramide resulted in a partial protection of apoptosis, which was maximal at 5 mM lithium (37% protection). When lithium was added 5 h before the apoptotic stimulus the neuroprotective effect of the ion was clearly increased (66% protection). This effect was not due to intracellular inositol depletion or inhibition of NMDA receptors. Our data broaden the nature of apoptotic insults being reversed by lithium, stressing the neuroprotective effects of the ion.


Assuntos
Apoptose/efeitos dos fármacos , Cerebelo/efeitos dos fármacos , Cerebelo/fisiologia , Lítio/farmacologia , Neurônios/fisiologia , Fármacos Neuroprotetores/farmacologia , Esfingosina/análogos & derivados , Animais , Células Cultivadas , Cerebelo/citologia , Esquema de Medicação , Feminino , Fosfatos de Inositol/antagonistas & inibidores , Lítio/administração & dosagem , Masculino , Neurônios/efeitos dos fármacos , Ratos , Ratos Wistar , Esfingosina/farmacologia
20.
Brain Res Bull ; 56(2): 119-23, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11704348

RESUMO

Exposure of cerebellar granule cells to 1-methyl-4-phenylpiridinium (MPP(+)) results in cell death. We have studied the implication of various membrane transporter systems on MPP(+) neurotoxicity, including the dopamine transporter system (DAT) and cationic amino acid transporters (CAT). We have showed a partial protection against MPP(+) toxicity when the dopamine transporter is inhibited by 1-[2-[bis(4-fluorophenyl)methoxy]ethyl]4-(3-phenylpropyl)piperazinedihydrochloride (GBR-12909). However, almost full protection is only achieved by the simultaneous addition of GBR-12909 and cationic amino acids. These results suggest two ways system of MPP(+) entrance into cerebellar granule cells: the DAT with high activity and the CAT with low activity. We also demonstrated that 5,7-dichlorokynurenic acid (MK-801) failed to protect against MPP(+) exposure, evidencing that N-methyl-D-aspartate (NMDA) receptor is not involved in the MPP(+)-induced cell death.


Assuntos
1-Metil-4-fenilpiridínio/metabolismo , Proteínas de Transporte/efeitos dos fármacos , Córtex Cerebelar/efeitos dos fármacos , Herbicidas/metabolismo , Intoxicação por MPTP/metabolismo , Glicoproteínas de Membrana , Proteínas do Tecido Nervoso , Neurônios/efeitos dos fármacos , Neurotoxinas/metabolismo , 1-Metil-4-fenilpiridínio/toxicidade , Sistemas de Transporte de Aminoácidos Básicos/efeitos dos fármacos , Sistemas de Transporte de Aminoácidos Básicos/metabolismo , Aminoácidos Básicos/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Proteínas de Transporte/metabolismo , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/metabolismo , Córtex Cerebelar/metabolismo , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina , Inibidores da Captação de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas/fisiologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Herbicidas/toxicidade , Intoxicação por MPTP/fisiopatologia , Masculino , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/metabolismo , Neurônios/metabolismo , Neurotoxinas/toxicidade , Piperazinas/farmacologia , Ratos , Ratos Wistar , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos
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