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1.
Encephale ; 44(6): 512-516, 2018 Dec.
Artigo em Francês | MEDLINE | ID: mdl-29195803

RESUMO

INTRODUCTION: Schizophrenia is a disorder affecting 1% of the population and is associated with severe functional impairment. Negative symptoms are responsible for the majority of this impairment, and many patients with schizophrenia have negative symptoms. However, their evaluation is still a challenge. Thus, standardized assessments are needed to facilitate identification of these symptoms. Many tools have been developed, but most are based on observer ratings. Self-evaluation can provide an additional outcome measure and allow patients to be more engaged in their treatment. The Self-evaluation of Negative Symptoms (SNS) has been developed recently. This is a remarkably understandable instrument for patients with schizophrenia as it allows them to readily complete it without assistance, providing information with respect to their own perception of negative symptoms. The SNS is a self-assessment that permits patients to evaluate themselves in 5 dimensions of negative symptoms. This validation study for the SNS revealed good psychometric properties alongside satisfactory acceptance by patients. AIM: This study was to confirm the validation of the French version of the self-evaluation of negative symptoms (SNS). METHODS: Patients with schizophrenia or schizoaffective disorder according to the DSM-IV-R, with a stable regimen of anti-psychotic drugs for the last two months, aged more than 18 years old were eligible for the study. Symptoms were rated using the SNS, the Scale for the Assessment of Negative Symptoms (SANS), the Calgary Depression Scale for Schizophrenics (CDSS), the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impression and Parkinsonism. Patients were asked to fulfill the SNS twice, 6 weeks apart. RESULTS: Sixty patients were evaluated. Cronbach's coefficient (α=0.8) showed good internal consistency. The SNS significantly correlated with the SANS (r=0.6), the negative sub-score of the BPRS (r=0.6) and the Clinician Global Impression on the severity of negative symptoms (r=0.7). SNS scores did not correlate with level of insight (r=0.08) or Brief Psychiatric Rating Scale positive sub-scores (r=0.2). SNS scores correlated with CDSS scores. However, we did not find correlation between the first item of the CDSS which evaluates depression and the "diminished emotional range" sub-score of SNS. The test-retest of SNS revealed no changes of scores at two evaluations 6 weeks apart. CONCLUSION: The acceptance by patients of the SNS was excellent. The French version of the SNS demonstrated a good internal consistency, good convergent validity and good discriminant validity. The study demonstrates the ability of patients with schizophrenia to accurately report their own experiences. Self-assessments of negative symptoms should be more widely employed in clinical practice because they may allow patients with schizophrenia to develop appropriate coping strategies.


Assuntos
Autoavaliação Diagnóstica , Testes Neuropsicológicos , Psicologia do Esquizofrênico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Autoavaliação (Psicologia) , Traduções , Adulto Jovem
2.
Front Genet ; 12: 740641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095996

RESUMO

Prostate Cancer (PC) is commonly known as one of the most frequent tumors among males. A significant problem of this tumor is that in early stages most of the cases course as indolent forms, so an active surveillance will anticipate the appearance of aggressive stages. One of the main strategies in medical and biomedical research is to find non-invasive biomarkers for improving monitoring and performing a more precise follow-up of diseases like PC. Here we report the relevant role of IGF2 and miR-93-5p as non-invasive biomarker for PC. This event could improve current medical strategies in PC.

3.
An Sist Sanit Navar ; 31 Suppl 1: 99-113, 2008.
Artigo em Espanhol | MEDLINE | ID: mdl-18528447

RESUMO

Infections of the central nervous system are frequent diseases in emergency care. They can have a bacterial, parasitic or viral origin. Initial symptoms can be non-specific, which can complicate and delay diagnosis, hence the extreme importance of all the information that can be obtained through anamnesis and physical exploration, with frequent complementary explorations. In the last hundred years, with the introduction of antibiotic drugs, there has been a significant fall in mortality secondary to meningoencephalitis, but in spite of that they continue to provoke high morbidity and mortality. Other phenomena, such as vaccination campaigns, migratory movements, infection by HIV and other states of immunosuppression, have given rise to important epidemiological changes such as the virtual disappearance of some infections or the appearance of others that rarely existed previously. The list of potential infections of the central nervous system is extensive, which is why in this review we set out, from the clinical, diagnostic and therapeutic point of view, those that are most frequent in our environment and some that, although very infrequent, might require emergency attention due to their severity.


Assuntos
Infecções do Sistema Nervoso Central , Tratamento de Emergência , Doença Aguda , Algoritmos , Infecções do Sistema Nervoso Central/diagnóstico , Infecções do Sistema Nervoso Central/terapia , Encefalite Viral/diagnóstico , Encefalite Viral/terapia , Humanos , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/terapia , Tuberculose Meníngea/diagnóstico , Tuberculose Meníngea/terapia
4.
Mol Hum Reprod ; 13(11): 821-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17766683

RESUMO

Poly(ADP-ribose)polymerases (PARP-1 and -2) are activated by DNA strand breaks to synthesize protein-bound ADP-ribose polymers from NAD+. The two enzymes are overexpressed in rat spermatocytes and are likely to play a role in meiosis. Indeed parp-2-/- mice, but not parp-1 knockouts, show hypofertility. Aside, PARP-1 and PARP-2 are both involved in DNA damage repair and signalling, but their relative contributions to such processes remain as yet unknown, largely because of the lack of PARP isoform-specific inhibitors that has precluded in vivo studies. Here, we used permeabilized rat primary spermatocytes or isolated spermatocyte nuclei and radiolabelled NAD+ to investigate potential isoform-specific effects on basic features of the poly(ADP-ribosyl)ation reaction, including size of ADP-ribose polymers at different NAD+ concentrations, extent of auto- versus etheromodification, and modulation of such reactions by the PARP inhibitor, PJ34. We found that PARP-1 automodification prevailed over PARP-2 modification. In addition, over 50% of cellular poly(ADP-ribose) was covalently bound to histones H1 and H2. The inhibitory effect of PJ34 appeared to be targeted mainly to the elongation step of the reaction. We propose that a different propensity of PARP-1 and PARP-2 to undergo automodification and/or catalyze etheromodification, both in terms of number of enzyme molecules being involved and amount of bound poly(ADP-ribose), may underlie distinct roles in the regulation of spermatocyte functions.


Assuntos
Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Espermatócitos/metabolismo , Animais , Núcleo Celular/metabolismo , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Histonas/metabolismo , Masculino , Ratos , Ratos Wistar
5.
J Colloid Interface Sci ; 316(2): 451-6, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17764684

RESUMO

The linear relationship of the yield stress with the square zeta potential may be used to determine the Hamaker constants in suspensions. In this work we have obtained the Hamaker constant for the attractive forces between anatase particles in aqueous suspensions using this method and compared them with those obtained by contact angle measurement. The results show excellent agreement.

6.
Biochim Biophys Acta ; 1007(2): 167-75, 1989 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2493263

RESUMO

Poly(ADP-ribosylation) of nuclear proteins has been investigated in rat testis under different experimental conditions to determine whether it is associated with somatic or germinal cells. Isolated, intact nuclei were incubated with [14C]NAD and extracted sequentially with 5% HClO4 and 0.25 M HCl, and labelled soluble proteins were analysed by reverse-phase high-performance liquid chromatography and acetic acid-urea polyacrylamide gel electrophoresis (pH 2.9). Results show that in normal adult testis a major acceptor protein for poly(ADP-ribose) in HClO4 extracts is the tissue-specific histone, H1t. Core histones and three proteins (alpha, beta and gamma) with low mobility on acetic acid-urea gels were the major acceptors identified in HCl extracts. Poly(ADP-ribosylation) of all the aforementioned proteins is very low in isolated intact nuclei of testis from 8-day-old animals (only spermatogonia present in seminiferous tubules), increases significantly by 16-day (pachytene spermatocytes appear) and reaches adult proportions by 32 days (condensing spermatids present). In the nuclei from cryptorchid testes, poly(ADP-ribosylation) of nuclear proteins resembles 8-day-old testis. It is concluded that (a) poly(ADP-ribosylation) of nuclear proteins in rat testis is closely correlated with spermatogenesis and can be inferred that is particularly active in the early stages of meiosis; (b) testis-specific proteins (histone H1t and low mobility proteins, alpha, beta and gamma) are poly(ADP-ribosylated) to higher specific radioactivity than somatic histones.


Assuntos
Proteínas Nucleares/metabolismo , Açúcares de Nucleosídeo Difosfato/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Espermatogênese , Testículo/metabolismo , Fatores Etários , Animais , Cromatografia Líquida de Alta Pressão , Proteínas de Grupo de Alta Mobilidade/metabolismo , Histonas/metabolismo , Masculino , Meiose , Processamento de Proteína Pós-Traducional , Ratos
7.
Biochim Biophys Acta ; 1399(2-3): 154-60, 1998 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-9765591

RESUMO

Using a poly(ADP-ribose) binding assay on protein blots we examined the ability of rat testis histone H1 variants to establish non-covalent interactions with the polymer. All the H1 variants bound ADP-ribose polymers; the binding was salt resistant and highly specific, occurring even in the presence of a large excess of competitor DNA. A comparison among the H1 variants showed that H1t has the highest affinity for poly(ADP-ribose). Long and branched poly(ADP-ribose) molecules were found to be preferentially involved in the interaction with the histone variants. The results further corroborate the concept that non-covalent interactions of poly(ADP-ribose) with target proteins may constitute an important mechanism to modulate chromatin structure.


Assuntos
Histonas/química , Poli Adenosina Difosfato Ribose/química , DNA/química , Eletroforese em Gel de Poliacrilamida , Endopeptidase K , Histonas/classificação , Poli Adenosina Difosfato Ribose/síntese química
8.
Biochim Biophys Acta ; 1079(1): 79-86, 1991 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-1832300

RESUMO

Poly(ADPribosylation) of nuclear proteins has been investigated in the nuclei from growing oviducts of intact and estrogen-treated spayed females of the lizard Podarcis s. sicula Raf. Isolated nuclei were incubated with [14C] NAD and nuclear proteins extracted in 0.2 m H2SO4. Labeled acid-soluble proteins were analysed by reverse-phase high-performance liquid chromatography (HPLC) and acetic acid-urea gel electrophoresis. The results reported here indicate that the ADPribosylation reaction is involved in modifying besides histone H2b, tissue specific proteins (SNPs and LMG-O). Moreover, comparable results have been obtained from nuclei prepared from the fully active oviduct of intact animals and spayed lizards stimulated with 17 beta-estradiol. It is concluded that the poly-(ADPribosylation) of hormone-induced proteins might play a role in the differentiation of the lizard oviduct.


Assuntos
Estrogênios/farmacologia , Proteínas Nucleares/metabolismo , Oviductos/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Ribonucleoproteínas/metabolismo , Aminoácidos/análise , Animais , Cromatografia Líquida de Alta Pressão , Eletroforese , Técnicas In Vitro , Lagartos , Ribonucleoproteínas Nucleares Pequenas
9.
Biochim Biophys Acta ; 1246(2): 151-9, 1995 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-7819282

RESUMO

An ADP-ribosylating system was detected in a crude homogenate from Sulfolobus solfataricus, a thermophilic archaeon, optimally growing at 87 degrees C. The archaeal ADP-ribosylation reaction was time-, temperature- and NAD-dependent. It proved to be highly thermostable, with about 30% decrease of 14C incorporation from [14C]NAD on incubation at 80 degrees C for up to 24 h. The main reaction product was found to be mono-ADP-ribose. Testing both [adenine-14C(U)]NAD and [adenine-14C(U)]ADPR as substrates, it was found that acceptor proteins were modified by ADP-ribose both enzymatically, via ADP-ribosylating enzymes, and via chemical attachment of free ADP-ribose, likely produced by NAD glycohydrolase activity. The synthesis of ADP-ribose-protein complexes was shown to involve mainly acceptors with molecular masses in the 40-100 kDa range, as determined by electrophoresis on polyacrylamide gel in the presence of sodium dodecyl sulphate.


Assuntos
Difosfato de Adenosina/metabolismo , Ribose/metabolismo , Sulfolobus/metabolismo , NAD/farmacologia , NAD+ Nucleosidase/metabolismo , Temperatura , Fatores de Tempo
10.
Eur J Cell Biol ; 80(3): 222-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11322386

RESUMO

The ability of rat germinal cells to recover from genotoxic stress has been investigated using isolated populations of primary spermatocytes and round spermatids. Using a comet assay at pH 10.0 to assess single strand breakage (SSB) in DNA, it was found that a high level of damage was induced by 5 Gy gamma-irradiation and acute exposure to 50 microM H2O2. This damage was effectively repaired during a subsequent recovery period of 1-3 hours culture in vitro but repair was significantly delayed in the presence of the poly(ADP-ribose)polymerase (PARP) inhibitor 3-aminobenzamide (3-ABA). Immunofluorescence detection of PARP with specific antibodies localised the protein to discrete foci within the nucleus of both spermatocytes and spermatids. Poly(ADP-ribose) (pADPR) could also be detected in spermatid nuclei following gamma-irradiation or H2O2 treatment. Moreover, PARP activation occurs both in spermatocytes and spermatids left to recover after both genotoxic stresses. The NO donors, 3-morpholino-sydnonimine (SIN-1) and S-nitrosoglutathione (SNOG), caused significant SSBs in both spermatocytes and spermatids. The effects of SIN-1 could be prevented by exogenous catalase (CAT), but not superoxide dismutase (SOD), in the cell suspensions. SNOG-induced SSBs were insensitive to both CAT and SOD. It is concluded that DNA in spermatocytes and spermatids is sensitive to damage by gamma-irradiation and H2O2 and that efficient repair of SSBs requires PARP activity.


Assuntos
Dano ao DNA/genética , Raios gama/efeitos adversos , Células Germinativas/efeitos dos fármacos , Células Germinativas/efeitos da radiação , Glutationa/análogos & derivados , Peróxido de Hidrogênio/efeitos adversos , Poli(ADP-Ribose) Polimerases/fisiologia , Animais , Benzamidas/farmacologia , Western Blotting , Catalase/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Ensaio Cometa , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Relação Dose-Resposta a Droga , Inibidores Enzimáticos , Glutationa/farmacologia , Masculino , Microscopia de Fluorescência , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Fármacos Neuroprotetores/farmacologia , Doadores de Óxido Nítrico/farmacologia , Compostos Nitrosos/farmacologia , Ratos , Ratos Wistar , S-Nitrosoglutationa , Espermátides/metabolismo , Espermatócitos/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Tempo
11.
Neurology ; 41(2 ( Pt 1)): 286-9, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1992378

RESUMO

We studied reciprocal inhibition of H-reflexes in the forearm flexor and extensor muscles in 14 patients with spastic hemiplegia secondary to a focal cerebral lesion and 14 normal volunteers. In the spastic limb, the Hmax/Mmax ratio was increased in both flexor and particularly extensor wrist muscles. The 3 normal inhibitory phases of reciprocal inhibition between extensor and flexor forearm muscles were markedly reduced on the spastic side of patients. The early disynaptic phase showed the greatest alteration. Reduced or absent inhibition between forearm muscles associated with increased spinal motoneuron excitability may be typical to spastic hemiplegia.


Assuntos
Antebraço , Hemiplegia/fisiopatologia , Espasticidade Muscular/fisiopatologia , Músculos/fisiopatologia , Inibição Neural , Encefalopatias/complicações , Reflexo H , Hemiplegia/etiologia , Humanos , Pessoa de Meia-Idade , Músculos/inervação , Tempo de Reação , Recrutamento Neurofisiológico , Valores de Referência
12.
Eur J Cancer ; 39(14): 2103-9, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12957467

RESUMO

In the present paper, we investigated the relationship between the growth inhibitory effects of recombinant interferon-alpha2b (rIFN-alpha2b) and poly (ADPR) polymerase-1 (PARP-1) activity in the human squamous KB cancer cell line. Growth inhibition of the KB cells mediated by 1000 IU/ml of rIFN-alpha2b was accompanied by a transient rise in PARP-1 specific activity 24 h after rIFN-alpha2b treatment, confirmed by both the increase of intracellular poly (ADP-ribose) content and the PARP-1 auto-modification level. At longer times of incubation, the onset of apoptosis accompanied KB cell growth inhibition, as demonstrated by both flow cytometry and western-blotting analysis showing an 89 kDa apoptotic fragment of PARP-1. Moreover, pretreatment of the cells with the PARP-1 inhibitor, 3-aminobenzamide (3-ABA), at non-cytotoxic concentrations (1 mM), reduced the cell-growth inhibition, cell-cycle perturbation and apoptosis caused by rIFN-alpha2b. Taken together, these results strongly suggest that PARP-1 may be directly involved in the effects of rIFN-alpha2b in the KB cancer cell line.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Interferon-alfa/uso terapêutico , Poli(ADP-Ribose) Polimerases/metabolismo , Western Blotting , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular , Divisão Celular , Ativação Enzimática , Citometria de Fluxo , Imunofluorescência , Humanos , Interferon alfa-2 , Células KB , Proteínas Recombinantes , Células Tumorais Cultivadas
13.
Acta Biochim Pol ; 42(2): 153-60, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8588457

RESUMO

We have previously demonstrated that a significant percentage of poly(ADPR) polymerase is present, as a tightly-bound form, at the third level of chromatin organisation defined by chromosomal loops and nuclear matrix. The present work is focused on the study of poly(ADP-ribosyl)ation of proteins present in these nuclear subfractions. It has been shown that, due to the action of poly(ADPR) polymerase, the ADP-ribose moiety of [14C]NAD is transferred to both loosely-bound and tightly-bound chromosomal proteins, which in consequence are modified by chain polymers of ADP-ribose of different lengths. Moreover, histone-like proteins seem to be ADP-ribosylated in chromosomal loops and nuclear matrix associated regions of DNA loops (MARS). A hypothesis can be put forward that the ADP-ribosylation system is functionally related to the nuclear processes, actively coordinated by the nuclear matrix.


Assuntos
Proteínas Nucleares/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Testículo/metabolismo , Animais , Antígenos Nucleares , Masculino , Modelos Biológicos , Ligação Proteica , Ratos
14.
Phys Med Biol ; 45(1): 241-52, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10661595

RESUMO

The aim of this research work has been the estimation of the stochastic risk for five barium examinations. The sample was the population attending the Radiological Service of the 'Nuestra Señora de la Victoria' University Hospital, who had been treated with some barium examinations, set in five different groups: oesophagus tract, oesophagus-gastric-duodenal tract, intestinal tract, enteroclysis and double enema. To estimate the stochastic risk, it is necessary to know the organ dose. This can be calculated from the dose-area product which allows us to determine the effective dose using software. The dose-area product is the most suitable quantity to measure in these types of examination. We have evaluated the contribution that each procedure provides to the genetically significant dose, somatically significant dose, collective effective dose, annual effective dose 'per capita' and detriment, which are useful for assessing the population risk of cancer or hereditary effects after x-ray exposure. The contribution to the genetically significant dose is 6.7 microGy, to the somatically significant dose 8.82 mSv-yr, 16.07 person-Sv for the collective effective dose, 0.03 mSv for the 'per capita' annual effective dose and the annual aggregated detriment is 0.33.


Assuntos
Bário , Sistema Digestório/diagnóstico por imagem , Esôfago/diagnóstico por imagem , Fatores Etários , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia/estatística & dados numéricos , Fatores de Risco , Espanha , Processos Estocásticos
15.
J Biomech ; 33(12): 1745-50, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11006404

RESUMO

The standard method used to calculate the ankle joint power contains deficiencies when applied to dynamic elastic response prosthetic feet. The standard model, using rotational power and inverse dynamics, assumes a fixed joint center and cannot account for energy storage, dissipation, and return. This study compared the standard method with new analysis models. First, assumptions of inverse dynamics were avoided by directly measuring ankle forces and moments. Second, the ankle center of rotation was corrected by including translational power terms. Analysis with below-knee amputees revealed that the conventional method overestimates ankle forces and moments as well as prosthesis energy storage and return. Results for efficiency of energy return were varied. Large differences between models indicate the standard method may have serious inadequacies in the analysis of certain prosthetic feet. This research is the first application of the new models to prosthetic feet, and suggests the need for additional research in gait analysis with energy-storing prostheses.


Assuntos
Membros Artificiais , , Modelos Biológicos , Articulação do Tornozelo/fisiologia , Elasticidade , Humanos , Rotação
16.
J Biomech ; 29(7): 979-83, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8809630

RESUMO

How small do pressure transducers need to be in order to faithfully measure the plantar pressure profiles (PPPs) under normal and diabetic feet? In this study, pressures were collected from five diabetic and six non-diabetic subjects using a commercial measurement system with 25 mm2 transducers. Discrete Fourier Transform techniques were then used to determine (i) the spatial frequency content of diabetic and non-diabetic PPPs, and (ii) the effects of quadrupling the transducer area (from 5 mm x 5 mm to 10 mm x 10 mm). When the data were filtered to represent the effects of using 10 mm x 10 mm transducers, it was found that the ensuing reductions in peak pressure in the toe region (50 kPa) were significantly greater than in all other regions of the foot (p < 0.05). There was a significant correlation between pressure underestimations and measured peak pressures in the metatarsal regions. Based on data collected with 25 mm2 transducers it was concluded that transducer sizes greater than 6.36 mm x 6.18 mm (medio-lateral and antero-posterior directions) would result in sub-optimal sampling of PPPs.


Assuntos
Diabetes Mellitus/fisiopatologia , Pé/fisiopatologia , Adulto , Análise de Fourier , Humanos , Pessoa de Meia-Idade , Pressão , Valores de Referência , Transdutores
17.
IEEE Trans Biomed Eng ; 47(3): 360-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10743778

RESUMO

The purpose of this paper is to present wavelet-based noise removal (WBNR) techniques to remove noise from biomechanical acceleration signals obtained from numerical differentiation of displacement data. Manual and semiautomatic methods were used to determine thresholds for both orthogonal and biorthogonal filters. This study also compares the performance of WBNR approaches with four automatic conventional noise removal techniques used in biomechanics. The conclusion of this work is that WBNR techniques are very effective in removing noise from differentiated signals with sharp transients while leaving these transients intact. For biomechanical signals with certain characteristics, WBNR techniques perform better than conventional methods, as indicated by quantitative merit measures.


Assuntos
Modelos Biológicos , Processamento de Sinais Assistido por Computador , Algoritmos , Braço/fisiologia , Artefatos , Fenômenos Biomecânicos , Mãos/fisiologia , Humanos , Movimento/fisiologia , Software
18.
Am J Sports Med ; 21(6): 887-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8291645

RESUMO

Individuals with anterior cruciate ligament deficiency typically do not have quadriceps activity during stance. This aberrant pattern has been termed "quadriceps avoidance" gait. We performed gait analysis during walking on 10 normal controls and 10 subjects 8 to 12 months after they had anterior cruciate ligament reconstruction using autogenous middle third of the patellar tendon. All patients had good subjective and objective results at the time of analysis. Differences in gait between subjects and controls persisted up to 12 months after surgery. Specifically, subjects with anterior cruciate ligament reconstructions demonstrated significant reductions in midstance knee flexion moments (P < 0.01) and tibially directed loading rates (P < 0.05) when compared with controls. However, the subjects had a net external flexion moment throughout most of the stance phase of gait, implying that quadriceps activity was present. After anterior cruciate ligament reconstruction, there is a tendency toward gait normalization, and a quadriceps avoidance mechanism is no longer present.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Marcha , Lesões do Ligamento Cruzado Anterior , Humanos , Cinética , Articulação do Joelho/fisiopatologia , Análise Multivariada , Amplitude de Movimento Articular
19.
Ital J Biochem ; 36(3): 166-80, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3112036

RESUMO

Poly(ADP-ribose)synthetase has been purified over 600-fold from HeLa cell nuclei. Upon electrophoresis on 9% polyacrylamide slab-gel in the presence of SDS, the purified enzyme resolved in two bands that showed similar apparent Mr values, 110,000 and 118,000. The aminoacid composition of the two components differed from compositions reported for the same enzyme from other sources. In accordance with other reports, the enzyme purified from HeLa cell nuclei exhibited an absolute dependence on DNA and its activity was modulated by changes in the histone concentration. Incubation of intact nuclei from HeLa cells with [14C]NAD resulted in the isolation of a poly(ADP-ribose)synthetase to which a definite radioactivity is bound. These results are taken as a further demonstration that the enzyme can be auto-ADP-ribosylated.


Assuntos
Núcleo Celular/enzimologia , Poli(ADP-Ribose) Polimerases/isolamento & purificação , Adenosina Difosfato Ribose/metabolismo , Aminoácidos/análise , Cromatografia , DNA/farmacologia , Eletroforese em Gel de Poliacrilamida , Células HeLa/enzimologia , Histonas/farmacologia , Humanos , Peso Molecular , NAD/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo
20.
J Rehabil Res Dev ; 28(3): 1-12, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1880746

RESUMO

In this study, a finite element (FE) model of a below-knee prosthesis of patellar tendon-bearing (PTB) design, and several altered variations of the model have been constructed. A load of approximately 1.5 times normal body weight (984 N) was applied at the heel of the model to simulate heelstrike conditions. The "base" model was then analyzed and revised iteratively until a model which provided consistency between soft tissue elastic modulus and socket displacement was developed. The interface normal and shear stresses obtained from the analysis of this revised base model were highest (about 961, and 463 KPa, respectively) at the distal anterior tip of the socket/stump. Proximally, higher normal stresses (72-78 KPa) were found medially and posteriorly. Proximal shear stresses were highest posteriorly (79 KPa), although shear stresses medially (51 KPa), and laterally (43 KPa), were also much higher than anteriorly (10 KPa). FE analyses were performed on the altered models to determine the relative effects on socket/stump interface stresses of altering the FE model of the prosthesis. Results of the analysis indicate that fabricating the prosthesis from a material with an elastic modulus ten times lower than that of the revised base model can produce reductions in the maximum pressure of up to 14 percent. Large decreases in maximum pressures (71 percent) resulted from the use of a suction socket rather than a conventional socket. Small changes in stump length (2 cm) caused relatively large pressure changes (16 to 18 percent).


Assuntos
Amputação Cirúrgica/reabilitação , Perna (Membro)/cirurgia , Próteses e Implantes/normas , Fenômenos Biomecânicos , Protocolos Clínicos , Simulação por Computador , Estudos de Avaliação como Assunto , Marcha , Humanos , Modelos Anatômicos , Pressão , Desenho de Prótese/normas
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