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1.
Parasitol Res ; 117(7): 2201-2206, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29744701

RESUMO

Sexual dimorphism is a well-documented phenomenon observed at all levels of the animal kingdom, with the inclusion of both sexes in clinical trials and basic research becoming mandatory. Regarding parasitosis, in several animal species, the signs and virulence of the disease may change depending on the sex of the affected animal. In the cestodiasis caused by Taenia solium and Taenia crassiceps, females are more susceptible to experimental infection than males. Cysticercosis by Taenia pisiformis in rabbits has acquired relevance due to its economic impact, namely affecting welfare and production. In America, specifically in Mexico, there are no formal reports on the infection with T. pisiformis metacestodes in populations of wild rabbits, despite being the country with more endemic species (about 15 species), among them, the volcanoes rabbits or the endangered teporingo (Romerolagus diazi). In this study, 31 wild rabbits were obtained by hunters of some regions of Morelos state during several hunting seasons, and sex, physiological stage, and number of metacestodes were recorded. A high frequency of infection by T. pisiformis metacestodes (67.7%) was found. Also, a higher susceptibility to this infection was observed in does (80% infected) compared to bucks (40%), finding 84.2% of metacestodes (235 metacestodes) in does and 15.8% of metacestodes (44 metacestodes) in bucks. The percentage of infection was higher in lactating compared with pregnant and non-pregnant does, with metacestodes lodging mainly in the uterus. Increasing our knowledge regarding parasitic infections can help us better understand transmission circles as well as the parasite-host interaction of these increasingly at risk rabbit species.


Assuntos
Cisticercose/veterinária , Suscetibilidade a Doenças , Interações Hospedeiro-Parasita/fisiologia , Coelhos/parasitologia , Animais , Cisticercose/epidemiologia , Cisticercose/parasitologia , Feminino , Lactação , Masculino , México , Gravidez , Fatores Sexuais , Taenia , Taenia solium
2.
Clin Transl Oncol ; 22(10): 1778-1785, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32096143

RESUMO

PURPOSE: Intestinal dysbiosis has emerged as a biomarker of response to immune checkpoint inhibitors (ICIs). It can be caused by antibiotics, although it may also result from the use of other drugs that have been studied to a lesser extent. The objective of our study was to analyze the association between the use of potentially dysbiosis-related drugs and survival in patients treated with ICIs in the clinical practice. MATERIALS AND METHODS: A retrospective, multicenter, cohort study was conducted. Clinicopathological variables were collected and the concomitant use of drugs was analyzed. A descriptive analysis of variables and overall survival, estimated by the Kaplan-Meier method, was performed, and association with various independent variables was assessed using Cox regression. RESULTS: We included 253 patients, mainly with non-small cell lung cancer and melanoma. The most commonly used drugs were acid reducers, prescribed to 55.3% of patients, followed by corticosteroids (37.9%), anxiolytic drugs (35.6%), and antibiotics (20.5%). The use of acid reducers (9 vs. 18 months, P < .0001), antibiotics (7 vs. 15 months, P < .017), anxiolytic drugs (8 vs. 16 months, P < .015), and corticosteroids (6 vs. 19 months, P < .00001) was associated with poorer overall survival. Furthermore, the greater the number of drugs used concomitantly with ICIs, the higher the risk of death (1 drug: hazard ratio, 1.88; CI 95%, 1.07-3.30; 4 drugs: hazard ratio, 4.19; CI9 5%, 1.77-9.92; P < .001). CONCLUSION: Response to ICIs may be influenced by the use of drugs that lead to intestinal dysbiosis. Although a confirmatory prospective controlled study is required, our findings should be taken into account when analyzing ICI efficacy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Disbiose/induzido quimicamente , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Melanoma/tratamento farmacológico , Corticosteroides/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiácidos/efeitos adversos , Ansiolíticos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Physiol Meas ; 40(4): 045001, 2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30921784

RESUMO

OBJECTIVE: This paper presents a method for breath-by-breath estimation of regional respiratory mechanics without the need for special manoeuvres (such as inspiratory pause or low-flow inflation) using electrical impedance tomography (EIT) associated with pressure/airflow waveforms. APPROACH: We developed a method to estimate regional parameters using the regional impedance fraction, by multiplying it by global flow and volume waveforms. A volume-dependent elastance model was used to obtain compliance, resistance, volume-independent (E 1), and volume-dependent (E 2) components. Three swine under invasive mechanical ventilation were used to assess internal consistency and illustrate potential applications of our method. One animal (case 1) was ventilated with a broad range of tidal volumes to compare the consistency between regional and global resistances and compliances. Two other animals (cases 2 and 3) had respiratory compliance decreased, respectively, by overdistension and collapse as quantified by x-ray computed tomography. MAIN RESULTS: In case 1, derived global estimates obtained from the independent regional estimates were strongly associated with direct measurements of global mechanics (correlation coefficients of 0.9976 and 0.9981 for compliances and resistances, respectively), suggesting consistency of our modelling. In cases 2 and 3, the development of lung overdistension and collapse over time was captured by regional estimates. CONCLUSIONS: Using EIT and pressure/airflow waveforms, regional respiratory parameters can be obtained cycle-by-cycle, refining lung function monitoring. SIGNIFICANCE: The method allows real-time monitoring of regional parameters and their trends over time, which might be helpful to differentiate deterioration in lung compliance due to overdistension or collapse.


Assuntos
Modelos Biológicos , Mecânica Respiratória , Tomografia , Animais , Impedância Elétrica , Suínos , Tomografia Computadorizada por Raios X
4.
Rev Clin Esp (Barc) ; 217(2): 79-86, 2017 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27932198

RESUMO

OBJECTIVES: The prophylaxis regimens for infectious endocarditis recommended by the clinical practice guidelines have recently changed. We do not know whether the current regimens are correctly followed in our setting. Our objective was to describe the approaches of various health professionals concerning these guidelines. MATERIAL AND METHODS: We conducted a survey in Cordoba, using a 16-item online questionnaire on this topic. We randomly selected a sample of 180 practitioners (20 cardiologists, 80 dentists and 80 primary care physicians), of whom 173 responded. RESULTS: Half of the participants were men; 52% had more than 20 years of professional experience. Some 88.3% of the participants considered that prophylaxis of endocarditis is effective (77.8% of the cardiologists, 93.7% of the dentist; p=.086). In general, prophylaxis is performed in conditions of clearly established risk (>90% of those surveyed). However, prophylaxis is also performed in a high proportion of cases with no risk of endocarditis, varying between 30 and 60% according to the procedure (mostly the dentists, between 36 and 67%, followed by the primary care physicians, between 28 and 59%). The antibiotic regimens employed varied significantly. The primary care physicians were furthest from the recommended regimen (only 25.8% used the recommended regimen vs. 54.4% of dentists and 72.2% of cardiologists; p=.002). CONCLUSIONS: Compliance with the recommendations on prophylaxis for endocarditis should be improved in our setting. We observed a tendency, especially among noncardiologists, to "overindicate" the prophylaxis.

5.
Clin Neuropathol ; 25(4): 193-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16866301

RESUMO

Glioblastoma is the most common primary tumor of the central nervous system, but the underlying genetic changes that give rise to these tumors are still poorly understood. We report a primary glioblastoma with an unusual age of presentation. The patient was a 22-year-old man with a survival of 16 months. Morphological findings showed an increase of cellularity with positive GFAP and EGFR expression, increase of proliferate index, vascular hyperplasia with glomeruloid structures and necrosis. Molecular analysis showed EGFR amplification. No mutations of the TP53 or amplification of MDM2 and CDK4 were detected. Neither homozygous deletion of the 9p21 locus genes nor aberrant methylation were found. The cytogenetic study showed a clonal karyotype. The metaphases presented, among other anomalies, a small ring chromosome and double-minutes chromosomes. Using FISH and CGH techniques, it was found that the ring chromosome was a partial trisomy of chromosome 7, and the region implicated corresponded to 7p13-q21. Partial trisomies in glioblastoma could play an important role in defining those regions where genes implicated in this tumor process may be found. We studied the possible correlation of these findings with the tumoral phenotype.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 7 , Genes erbB-1/genética , Glioblastoma/genética , Cromossomos em Anel , Adulto , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/ultraestrutura , Cromossomos Humanos Par 7/ultraestrutura , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Amplificação de Genes , Proteína Glial Fibrilar Ácida/metabolismo , Glioblastoma/cirurgia , Glioblastoma/ultraestrutura , Humanos , Imuno-Histoquímica , Cariotipagem , Masculino , Trissomia/patologia
6.
Gene ; 300(1-2): 97-104, 2002 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-12468091

RESUMO

We present a coding measure which is based on the statistical properties of the stop codons, and that is able to estimate accurately the variation of coding content along an anonymous sequence. As the stop codons play the same role in all the genomes (with very few exceptions) the measure turns out to be species-independent. We show results both for prokaryotic and for eukaryotic genomes, indicating, first, the accuracy of the measure, and, second, that better prediction is achieved if the measure is applied on homogeneous, isochore-like sequences than if it is applied following the standard moving window approach. Finally, we discuss on some of the possible applications of the measure.


Assuntos
Códon de Terminação/genética , Fases de Leitura Aberta/genética , Animais , Bacillus subtilis/genética , Composição de Bases , Bases de Dados de Ácidos Nucleicos , Drosophila melanogaster/genética , Genoma Humano , Humanos , Isocoros/genética , Especificidade da Espécie , Estatística como Assunto
7.
Gene ; 300(1-2): 105-15, 2002 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-12468092

RESUMO

Here we present a study of statistical correlations among different positions in DNA sequences and their implications by directly using the autocorrelation function. Such an analysis is possible now because of the availability of large sequences or even complete genomes of many organisms. After describing the way in which the autocorrelation function can be applied to DNA-sequence analysis, we show that long-range correlations, implying scale independence, appear in several bacterial genomes as well as in long human chromosome contigs. The source for such correlations in bacteria, which may extend up to 60 kb in Bacillus subtilis, may be related to massive lateral transfer of compositionally biased genes from other genomes. In the human genome, correlations extend for more than five decades and may be related to the evolution of the 'neogenome', a modern evolutionary acquisition composed by GC-rich isochores displaying long-range correlations and scale invariance.


Assuntos
DNA/genética , Análise de Sequência de DNA/estatística & dados numéricos , DNA Bacteriano/genética , Genoma Bacteriano , Genoma Humano , Humanos , Análise de Sequência de DNA/métodos , Estatística como Assunto
8.
Gene ; 276(1-2): 47-56, 2001 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-11591471

RESUMO

Analytical DNA ultracentrifugation revealed that eukaryotic genomes are mosaics of isochores: long DNA segments (>>300 kb on average) relatively homogeneous in G+C. Important genome features are dependent on this isochore structure, e.g. genes are found predominantly in the GC-richest isochore classes. However, no reliable method is available to rigorously partition the genome sequence into relatively homogeneous regions of different composition, thereby revealing the isochore structure of chromosomes at the sequence level. Homogeneous regions are currently ascertained by plain statistics on moving windows of arbitrary length, or simply by eye on G+C plots. On the contrary, the entropic segmentation method is able to divide a DNA sequence into relatively homogeneous, statistically significant domains. An early version of this algorithm only produced domains having an average length far below the typical isochore size. Here we show that an improved segmentation method, specifically intended to determine the most statistically significant partition of the sequence at each scale, is able to identify the boundaries between long homogeneous genome regions displaying the typical features of isochores. The algorithm precisely locates classes II and III of the human major histocompatibility complex region, two well-characterized isochores at the sequence level, the boundary between them being the first isochore boundary experimentally characterized at the sequence level. The analysis is then extended to a collection of human large contigs. The relatively homogeneous regions we find show many of the features (G+C range, relative proportion of isochore classes, size distribution, and relationship with gene density) of the isochores identified through DNA centrifugation. Isochore chromosome maps, with many potential applications in genomics, are then drawn for all the completely sequenced eukaryotic genomes available.


Assuntos
DNA/genética , Células Eucarióticas/metabolismo , Genoma , Animais , Composição de Bases , Mapeamento Cromossômico , DNA Fúngico/genética , DNA de Plantas/genética , Sequência Rica em GC/genética , Genes/genética , Variação Genética , Genoma Fúngico , Genoma Humano , Genoma de Planta , Humanos , Complexo Principal de Histocompatibilidade/genética
9.
Obes Surg ; 14(7): 1012-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15329195

RESUMO

A 41-year-old woman in November 2002 underwent a gastric bypass by the Capella technique for morbid obesity. Almost 1 year after the surgery, she developed severe vomiting. Radiological studies confirmed a severe stenosis of the gastrojejunal anastomosis. Two pneumatic dilatations of the stenosis failed. In February 2004, she underwent resection of the stenotic anastomosis. Histology showed an intact mucosa and beneath it an abscess filled with numerous filamentous microorganisms, with typical features of Actinomyces. With the diagnosis of gastric actinomycosis, she received a postoperative course of antibiotherapy with imipenem and was discharged after an uneventful recovery. Gastric actinomycosis is a rare infection, of which only 19 additional cases have been reported in the literature. To our knowledge, this is the first case to affect a patient following batriatric surgery. The reported cases of this entity are reviewed, and the diagnostic criteria that could avoid surgery in these cases are discussed.


Assuntos
Actinomicose/etiologia , Derivação Gástrica/efeitos adversos , Obesidade Mórbida/cirurgia , Gastropatias/etiologia , Actinomicose/diagnóstico , Adulto , Feminino , Humanos , Gastropatias/diagnóstico
10.
Histol Histopathol ; 2(4): 357-68, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2980739

RESUMO

The pathogenesis of skeletal muscle necrosis produced by Tityus Serrulatus venom was studied by means of light microscopy and electron microscopy. Wistar rats were inoculated subcutaneously, at some distance from the muscles under study, with a sublethal dose of scorpion venom. Samples were taken of the tibialis anterior muscles of both rear legs, 2, 7 and 24 hours postinoculation. Light microscopy analysis after 2 hours revealed certain changes identified as "delta lesions", and also the presence of hyperconcentrated muscle cells. Electron microscopy confirmed these lesions and also enabled us to identify a degree of discontinuity in the plasma membrane with a persistence of the basal membrane. Hyperconcentrated fibers could still be observed 7 hours postinoculation. Histochemical analysis revealed high levels of calcium within the fibers. 24 hours after inoculation with the venom, numerous phagocytic cells were found in the degenerated fibers. Muscle cells were also found to have undergone alterations indicative of an ischemic process. The most characteristic finding 7 days postinoculation was the appearance of regenerative fibers. After thirty days the muscles regained their normal appearance. It is suggested that Tityus Serrulatus venom induces myonecrosis by means of a twofold action: direct action, which gives rise in the first place to a rupture of the plasma membrane, permitting a massive entry of calcium this being a key factor in the process of cell lesion and an assumed indirect action due to ischemia.


Assuntos
Músculos/patologia , Venenos de Escorpião/toxicidade , Animais , Microscopia Eletrônica , Músculos/efeitos dos fármacos , Músculos/ultraestrutura , Necrose , Ratos , Ratos Endogâmicos , Valores de Referência , Escorpiões
11.
Am J Infect Control ; 29(2): 99-103, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11287877

RESUMO

OBJECTIVES: To evaluate the ambulatory surgical site infection rate and risk factors associated with surgical site infection. METHODS: We conducted a case-control analysis of all ambulatory surgeries between January 1, 1993, and December 31, 1997. The frequency of surgical site infection per 100 surgeries was calculated. The odds ratio (OR) was estimated by using logistic regression analysis. SETTING: A 140-bed tertiary-care teaching hospital for adult patients with cancer. RESULTS: The study followed 1350 outpatient surgeries. Thirty-eight patients had a surgical site infection (rate per 100 surgeries: 2.8). The risk factors statistically associated with surgical site infection were postoperative antibiotics (OR = 7.5; 95% CI, 2.5-23.0), and surgical time >35 minutes (OR = 2.4; 95% CI, 1.1-5.5). CONCLUSIONS: The surgical site infection rate for same-day surgery at our hospital is within the limits reported in the literature and below the rates reported previously for inpatient surgeries at our hospital. Full review of medical records and microbiology reports at day 30 allowed us to identify infections that otherwise would have been missed. Postoperative antibiotics may increase the risk of infection.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/efeitos adversos , Neoplasias/cirurgia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Adulto , Procedimentos Cirúrgicos Ambulatórios/estatística & dados numéricos , Procedimentos Cirúrgicos Ambulatórios/tendências , Antibacterianos/uso terapêutico , Estudos de Casos e Controles , Hospitais de Ensino , Humanos , Controle de Infecções/métodos , Controle de Infecções/normas , Modelos Logísticos , México/epidemiologia , Razão de Chances , Cuidados Pós-Operatórios/métodos , Cuidados Pós-Operatórios/estatística & dados numéricos , Fatores de Risco , Infecção da Ferida Cirúrgica/microbiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Fatores de Tempo
12.
Am J Surg ; 178(1): 55-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10456704

RESUMO

An important role still exists for the creation of surgical portasystemic shunts. Multiple techniques have been described. However, no particular one is satisfactory for all clinical situations. The objective of the present paper is to describe an alternative surgical technique for the creation of a decompressive portasystemic shunt. This technique consists of an end-to-side anastomosis between the inferior mesenteric vein and the left renal vein. In our experience, the inferior mesenteric vein to left renal vein anastomosis may be a useful portal decompressive shunt for patients with otherwise difficult peri-portal or peri-pancreatic anatomic exposures. This technique should be a useful tool in the armamentarium of surgeons dealing with patients who need portal decompressive surgical shunts.


Assuntos
Hipertensão Portal/cirurgia , Veias Mesentéricas/cirurgia , Derivação Portossistêmica Cirúrgica/métodos , Veias Renais/cirurgia , Anastomose Cirúrgica/métodos , Descompressão Cirúrgica , Humanos , Pressão na Veia Porta
13.
Mutat Res ; 245(2): 61-5, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2215552

RESUMO

Treatment of human lymphocytes with vanadium pentoxide (V2O5) was not found to increase the frequency of structural chromosomal aberrations (CA) and sister-chromatid exchanges (SCE). However, V2O5 significantly increased polyploid cell frequency; also, the mitotic index (MI) was significantly decreased, and the average generation time (AGT) was significantly increased. Finally, the frequency of cells with satellite associations (SA), the frequency of SA per cell, and the frequency of chromosomes associated increased in treated cultures.


Assuntos
Ciclo Celular/efeitos dos fármacos , Aberrações Cromossômicas , Linfócitos/citologia , Mutagênicos/farmacologia , Troca de Cromátide Irmã/efeitos dos fármacos , Compostos de Vanádio , Vanádio/farmacologia , Adulto , Células Cultivadas , Humanos , Cinética , Linfócitos/efeitos dos fármacos , Masculino , Testes de Mutagenicidade
14.
Clin Rheumatol ; 16(2): 154-9, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9093797

RESUMO

A multicentre, double-blind, randomised, parallel group study was undertaken to investigate the efficacy and safety of aceclofenac (123 patients, 100 mg twice daily) in comparison to piroxicam (117 patients, 20 mg once daily and placebo once daily) in patients with osteoarthritis of the knee. The treatment period of two months was preceded by a washout period of one week duration. On completion of the study, patients in both aceclofenac and piroxicam-treated groups exhibited significant improvement in pain intensity and functional capacity of the affected knee, as represented by the Osteoarthritis Severity Index (OSI) (p < 0.0001 and p < 0.001 respectively). This was further substantiated following the patient's assessment of pain intensity using the Visual Analogue Scale (VAS), in which significant improvements were demonstrated at all time points for each treatment group (p < 0.001). Although both treatment groups showed a significant improvement in all investigator's clinical assessments (functional exploration of the knee, knee flexion and extension (EXT)), there were no significant differences between the groups. There was, however, a more rapid improvement in knee flexion in the aceclofenac group after 15 days of treatment. Both aceclofenac and piroxicam were well tolerated by patients, the most commonly reported adverse events being gastrointestinal, although their incidence was low. Only 24 patients on aceclofenac, as opposed to 33 on piroxicam complained of dyspepsia, epigastralgia and pyrosis. While 7 patients in each group were withdrawn because of adverse events, only one patient with piroxicam was withdrawn because of severe upper gastrointestinal bleeding. Twice as many reports of fecal blood loss were made in the piroxicam group in comparison to the aceclofenac group. In summary, this study confirms the therapeutic efficacy of aceclofenac and suggests that it is a well-tolerated alternative NSAID to piroxicam in the treatment of osteoarthritis.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Diclofenaco/análogos & derivados , Osteoartrite/tratamento farmacológico , Piroxicam/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Diclofenaco/uso terapêutico , Método Duplo-Cego , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor
15.
Adv Exp Med Biol ; 476: 197-208, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10949666

RESUMO

Bovine adrenal medulla microvascular endothelial cells used in this study undergo cellular proliferation and differentiation upon culturing in vitro as observed both by light and scanning electron microscopy. Cells also respond to the growth promoting activity of serum and basic fibroblast growth factor (FGF2). Flow cytometric analysis of a synchronized culture established that cells take 68 hours to complete one cell cycle spending 36 hours in the G1 phase, 8 hours in the S phase, and 24 hours in the G2 + M phase when cultured in EMEM containing 2% heat-inactivated fetal bovine serum (FBS). At 10% serum, or in the presence of FGF2 (10 ng/ml-100 ng/ml) length of the cell cycle is reduced to 56 hours due to shortening of the G1 phase by 12 hours. Tunicamycin (a glucosamine-containing pyrimidine nucleotide), and an inhibitor of glucosaminyl-1-phosphate (GlcNAc 1-P) transferase, the first step of Glc3Man9GlcNAc2-PP-Dol (OSL) biosynthesis is found to inhibit the endothelial cells proliferation by inducing apoptosis as observed by flow cytometry and DNA laddering. Cell shrinkage, compaction of nuclei, membrane fragmentation, etc., typical of apoptotic response are frequently seen by light microscopy in the presence of tunicamycin. Scanning electron microscopy also exhibited a considerable amount of cell surface blebbing. Accumulation of an immunopositive cell specific asparagine-linked (N-linked) glycoprotein, Factor VIII:C in the absence of Glc3Man9GlcNAc2-PP-Dol in tunicamycin treated cells has been proposed as an apoptotic triggering mechanism under the current experimental conditions.


Assuntos
Apoptose/efeitos dos fármacos , Endotélio Vascular/citologia , Manosiltransferases/metabolismo , Neovascularização Patológica/metabolismo , Açúcares de Poli-Isoprenil Fosfato/biossíntese , Tunicamicina/farmacologia , Animais , Asparagina/metabolismo , Capilares/citologia , Bovinos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Células Clonais , Fator VIII/metabolismo , Glicoproteínas/metabolismo , Tunicamicina/metabolismo
17.
Arch Neurobiol (Madr) ; 55(3): 89-98, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1497417

RESUMO

Blink reflex (BR) and brainstem auditory evoked potentials (BAEP) were recorded from 168 patients with several diagnostic categories of multiple sclerosis, from which 98 complained brainstem symptoms (BSS+). From the whole group, the BR showed a higher degree of abnormality (45.75%) than BAEP (27.95). This range increased in the group BSS+ (52.15% for the BR and 34.9% for the BAEP) and even more when sings or symptoms of brainstem were present at the time of exploration (BSS+P) 60.4% for the BR and 41.3% for BAEP. Among patients who never complained brainstem symptoms, the BR disclosed a subclinical lesion in the 33.3% and the BAEP in the 16.9%. The combination of BR and BAEP were more useful than an isolated test. The localization of the lesion both clinically and in the BR were mostly on the pons. Light correlation between the presence of isolated or multiple symptoms and the disorder in the BR were present. Facial myokymia and internuclear ophthalmoplegia were most often associated with disorder in the BR, in both, the commonest localization was on the pons, and in the former about the motor nucleus of the facial nerve.


Assuntos
Piscadela , Tronco Encefálico/fisiopatologia , Potenciais Evocados Auditivos do Tronco Encefálico , Esclerose Múltipla/fisiopatologia , Reflexo Anormal , Adolescente , Adulto , Criança , Nervos Cranianos/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Rev Med Chil ; 127(5): 547-55, 1999 May.
Artigo em Espanhol | MEDLINE | ID: mdl-10451624

RESUMO

BACKGROUND: Alterations in the head position and in cervical curvature are associated with mandibular dysfunction, an increased vertical occlusal dimension, upper airways obstruction and bad postural behaviors at work among other conditions. AIM: To perform a cephalometric analysis in young adults. SUBJECTS AND METHODS: Lateral cervical X-ray examinations were performed in 46 university students (26 female) aged 19 years old as a mean, Cephalometric landmarks and planes reported by Sollow & Tallgren, determined by investigators, were used for radiographic analysis. RESULTS: The combined error of the method did not exceed 0.9 degree for any studied variable. Mean craniocervical angulations were 102 degrees for OPT-SNL, 109 degrees for CVT-SNL, 94.8 degrees for cranium-C2 and 105 for SN-vertical. There were significant sex differences in craniocervical angulations and these were abnormal in two thirds of subjects studies. The Forward Head Position is characterized by a cervical compensation with head inclination. This abnormal postural position showed a dolichofacial growth and an alteration of hyoid angle. CONCLUSIONS: The craniocervical position appeared to be related to a vertical craniofacial growth pattern.


Assuntos
Cefalometria , Vértebras Cervicais/anatomia & histologia , Curvaturas da Coluna Vertebral , Adulto , Feminino , Humanos , Masculino , Postura
19.
J Theor Biol ; 160(4): 457-70, 1993 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-8501918

RESUMO

A new method to determine entropic profiles in DNA sequences is presented. It is based on the chaos-game representation (CGR) of gene structure, a technique which produces a fractal-like picture of DNA sequences. First, the CGR image was divided into squares 4-m in size (m being the desired resolution), and the point density counted. Second, appropriate intervals were adjusted, and then a histogram of densities was prepared. Third, Shannon's formula was applied to the probability-distribution histogram, thus obtaining a new entropic estimate for DNA sequences, the histogram entropy, a measurement that goes with the level of constraints on the DNA sequence. Lastly, the entropic profile for the sequence was drawn, by considering the entropies at each resolution level, thus providing a way to summarize the complexity of large genomic regions or even entire genomes at different resolution levels. The application of the method to DNA sequences reveals that entropic profiles obtained in this way, as opposed to previously published ones, clearly discriminate between random and natural DNA sequences. Entropic profiles also show a different degree of variability within and between genomes. The results of these analyses are discussed in relation both to the genome compartmentalization in vertebrates and to the differential action of compositional and/or functional constraints on DNA sequences.


Assuntos
Simulação por Computador , Teoria dos Jogos , Teoria da Informação , Análise de Sequência de DNA , Termodinâmica , Animais , Sequência de Bases , Humanos , Vertebrados/genética
20.
Bioinformatics ; 15(12): 974-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10745986

RESUMO

MOTIVATION: DNA sequences are formed by patches or domains of different nucleotide composition. In a few simple sequences, domains can simply be identified by eye; however, most DNA sequences show a complex compositional heterogeneity (fractal structure), which cannot be properly detected by current methods. Recently, a computationally efficient segmentation method to analyse such nonstationary sequence structures, based on the Jensen-Shannon entropic divergence, has been described. Specific algorithms implementing this method are now needed. RESULTS: Here we describe a heuristic segmentation algorithm for DNA sequences, which was implemented on a Windows program (SEGMENT). The program divides a DNA sequence into compositionally homogeneous domains by iterating a local optimization procedure at a given statistical significance. Once a sequence is partitioned into domains, a global measure of sequence compositional complexity (SCC), accounting for both the sizes and compositional biases of all the domains in the sequence, is derived. SEGMENT computes SCC as a function of the significance level, which provides a multiscale view of sequence complexity.


Assuntos
Algoritmos , Análise de Sequência de DNA/métodos , Apresentação de Dados , Escherichia coli/genética , Computação Matemática , Modelos Genéticos , Estrutura Molecular , Estrutura Terciária de Proteína/genética , Software , Interface Usuário-Computador
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