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1.
Acta Orthop Belg ; 85(4): 525-534, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32374244

RESUMO

Unstable trochanteric fractures and fractures with reverse obliquity pose difficulty in fixation. In recent years, intramedullary nails, for the treatment of comminuted and unstable intertrochanteric hip fractures, are becoming more popular relative to conventional, sliding hip screws. The purpose of our study was to evaluate the result of Trochanteric femoral nailing in comminuted, unstable Trochanteric femur fracture in terms of anatomical restoration and functional outcome. It is a prospective and without control study. Trochanteric femoral nailing has been done in comminuted unstable inter-trochanteric fracture femur (AO A2.2 to A3.3) of 25 patients and they are followed up postoperatively for at least 12 months. Pre-operative and post-operative clinical and radio-logical parameters are compared accordingly. Union in all cases. Overall complication rate 12% including some implant related complications. Functional outcome on Harris Hip Score is comparable with standard literature. For treatment of intertrochanteric hip fractures, particularly with comminuted fracture fragments, intramedullary devices offer beneficial features, such as closed insertion, a shorter lever arm, and controlled telescoping of the head-neck fragment. Insertion of the nail through the tip of the greater trochanter requires less dissection and may lead to less blood loss and fewer wound complications, as well as earlier postoperative mobility. Further biomechanical and clinical studies are necessary to validate the efficacy of the trochanteric femoral nail. Level of Evidence : Level III therapeutic study.


Assuntos
Pinos Ortopédicos , Fixação Intramedular de Fraturas/métodos , Fraturas Cominutivas/cirurgia , Fraturas do Quadril/cirurgia , Adulto , Idoso , Avaliação da Deficiência , Feminino , Fraturas Cominutivas/diagnóstico por imagem , Fraturas do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia
2.
Int J Spine Surg ; 10: 17, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27441175

RESUMO

BACKGROUND: Chronic compression of the cervical spinal cord leads to a clinical syndrome of cervical spondylotic myelopathy (CSM). Clinical symptoms of cervical spondylotic myelopathy (CSM) or cervical myeloradiculopathies result in spinal cord and root dysfunction. The primary aims of surgical intervention for multilevel myelopathy are to decompress the spinal cord and maintain stability of the cervical spine. Secondary aims are to minimize complications which include long-term pain and motion loss. Laminoplasty as either single-door or double-door technique and with/without instrumentation is an established mode of surgical treatment. The purpose of our study was to evaluate the result of single-door laminoplasty technique, supported with instrumented fixation in patients with multilevel degenerative cervical spondylotic myeloradiculopathy. METHODS: A prospective and without control study has been conducted in the institution in 17 patients with CSM, operated by canal expansive single-door laminoplasty (Hirabayashi technique) between April 2010 to April 2015. These patients were followed up for at least 3 years with both clinical and radiographic evaluations. RESULTS: On clinical evaluation, 15 of the 17 patients (87%) experienced relief of their symptoms. According to the Nurick classification, 11 patients' demonstrated improvement by one grade, two patients improved by two grades, two patients were unchanged and two had worsening of the Nurick grade. CONCLUSIONS: The results of this study regarding the use of open-door laminoplasty with instrumented fixation suggest that this technique is a satisfactory alternative for cases of multilevel cervical spondylotic myelopathy without deformation. LEVEL OF EVIDENCE: Level III therapeutic study.

3.
Life Sci ; 66(3): 193-200, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10665993

RESUMO

High mobility group (HMG) proteins in human kidney T1 and murine L 929 cells have been investigated after exposure to heat shock at 41 degrees C and their influence on the organizational change of chromatin under heat shock condition has been examined. Results reveal that the two cell lines show differential response of the HMG proteins 1 & 2 and 14 & 17 to heat shock. Neither T1 nor L 929 cells show significant differences in response to heat shock with respect to the binding affinities of HMG proteins 1 & 2 or 14 & 17 to DNA, as revealed by DNase I sensitivity and chromatin reconstitution assays. Furthermore, the HMG proteins of both the non-heat shocked and the heat shocked T1 and L 929 cells can recover their chromatin activity following reconstitution. These findings suggest that although the HMG proteins might undergo some change in response to heat shock, their inherent potential of reassociation with DNA is still retained.


Assuntos
Proteínas de Grupo de Alta Mobilidade/biossíntese , Temperatura Alta , Animais , Linhagem Celular , Cromatina/química , Desoxirribonuclease I/farmacologia , Proteínas de Grupo de Alta Mobilidade/análise , Proteínas de Grupo de Alta Mobilidade/genética , Humanos , Rim/citologia , Camundongos
5.
Indian J Exp Biol ; 31(3): 210-4, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8500835

RESUMO

Premature chromosome condensation (PCC) was induced in Drosophila melanogaster cell hybrids, with Drosophila mitotic cells and interphase cells at different phases (G1,G1-S,S,S-G2 of the cell cycle, and from male and female, using standard cell fusion technique with polyethylene glycol (PEG). A combination of Feulgen and autoradiography was used to enhance the resolution of the PCC plates. It was possible to identify the characteristics of PCC's at G1, S and G2, and the transitory intermediate phases, which are comparable with respect to the characteristics of PCC's previously described for other species. Using the combined Feulgen-autoradiography technique it was possible to critically resolve the different phases including the transitory intermediate phases in greater detail. Analysis and comparison of results obtained from M (female) x S (female/male) and M (female) x G2 (female/male) hybrids have revealed that the X chromosome from the male could be identified as a distinct acrocentric entity which showed clear allocyclic, heteropycnotic characteristics. The results thus lead us to suggest that the X chromosome in such synkaryons is indeed early replicating as is the X chromosome of male larval salivary gland of Drosophila. The X chromosome morphology is also distinctly at an advanced stage of the cell cycle. On the basis of these findings it is concluded that X chromosome is hyperactive in the normally dividing diploid cells.


Assuntos
Mecanismo Genético de Compensação de Dose , Drosophila melanogaster/genética , Animais , Ciclo Celular , Cromossomos/ultraestrutura , Replicação do DNA , Diploide , Feminino , Células Híbridas/ultraestrutura , Masculino
6.
Indian J Exp Biol ; 30(7): 557-66, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1459627

RESUMO

Replicative behaviour of two hyperploid autosomal arms (2L and 3L) of D. melanogaster has been analysed by 3H-thymidine autoradiography. Results reveal that hyperploid autosomal arms (2L-trisomy or 3L-trisomy) replicate synchronously with other disomic non-homologous chromosome arms i.e. there is no asynchrony in the initial mid or late phase of replication patterns between the trisomic 2L or trisomic 3L and disomic arms, suggesting that the extra dose of an autosomal arm can not alter the inherent pattern of replication of that arm. Results further reveal that 2L-trisomy or 3L-trisomy does not impart any influence on X-chromosomal replication in either sex. It is suggested from these results that change in the genomic dose of autosome does not play any role in modulating the replicative organization of the autosomes, 2L and 3L. Thus, although a regulatory mechanism of autosomal dosage compensation does exist for Drosophila, the hierarchy of genetic programming of regulation for X-chromosomal and autosomal dosage compensation might be different. Neither hypertranscriptive activity nor faster replication pattern of the male X-chromosome is influenced by 2L- or 3L-trisomy.


Assuntos
Aneuploidia , Replicação do DNA/fisiologia , Mecanismo Genético de Compensação de Dose , Drosophila melanogaster/genética , Cromossomo X/fisiologia , Animais , Feminino , Masculino
7.
Indian J Exp Biol ; 28(4): 301-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2351414

RESUMO

Phosphopeptides (PPs) isolated from highly purified calf thymus DNA (N-DNA) and extracted from calf thymus nuclei were fractionated, and the effect of one PP fraction on DNA replication has been examined. In the absence of inhibitors, the increasing PP concentration caused a linear decrease of 3H-thymidine uptake in L5178Y cells. If PP fraction was mildly hydrolysed with 1NHCl, the decrease in uptake was much steeper. The studies in which the inhibitors were used revealed that by the addition of the unhydrolysed PP fraction the inhibition of 3H-thymidine uptake by alpha-amanitin could be completely overcome, and that the inhibition by puromycin was reduced to 65-77% of the control. With puromycin, there was a gradual decrease of 3H-thymidine uptake with PP concentration above 3 mg/ml. The PPs gave an increase in incorporation of 3H-thymidine even after removal of alpha-amanitin and puromycin; thus, it is suggested that there is no direct interaction of either inhibitor with PP in the cell. Data on the utilization of 3H-cytidine for the synthesise of new DNA suggest that PP fraction might cause an acceleration of DNA replication.


Assuntos
Núcleo Celular/metabolismo , Replicação do DNA , DNA/análise , Fosfopeptídeos/farmacologia , Animais , Bovinos , Linhagem Celular , Cromatografia por Troca Iônica , DNA/biossíntese , Fosfopeptídeos/isolamento & purificação , Timidina/metabolismo , Timo
8.
Chromosoma ; 99(1): 71-5, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2111237

RESUMO

Chromosomal RNA synthesis of the three heat shock puffs 87A, 87C and 93D examined in trisomic 3L (T3L) and trisomic 2L (T2L) strains of Drosophila melanogaster and compared with that of Oregon R+ and compound stocks of the 3rd [C(3L)VGI ru st; F(3R)VDI es/F(3R)VDI es] and 2nd [C(2L)SHI+; F(2R) bw] chromosomes. The activity at two different temperatures (22 degrees and 37 degrees C) was monitored by [3H]uridine autoradiography. The results that while in the control T3L and T2L nuclei (22 degrees C), the 93D puff shows a higher level of transcriptional activity than in the Oregon R+ or compound stocks used as controls, in T3L and T2L nuclei from heat-shocked sets (37 degrees C), 93D does not show further induction compared with heat-shocked controls, and the 87C puff is 2.8 times more active than the 87A puff. These results suggest that there may be a direct functional and/or regulatory relationship between the activity of 93D and certain sequence specific activity of 87C, and that an optimum level of activity delimits the activity of the heat shock puff 93D in D. melanogaster.


Assuntos
Cromossomos/metabolismo , Drosophila melanogaster/genética , Proteínas de Choque Térmico/genética , Transcrição Gênica , Trissomia , Animais , Cromossomos/ultraestrutura , Temperatura Alta
11.
J Cell Sci ; 86: 35-45, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3116003

RESUMO

Cytophotometric analysis of the in situ binding affinity of non-histone chromosomal protein (NHCP) to the polytenic X chromosome and autosome of Drosophila melanogaster has been carried out using Feulgen-Napthol Yellow S staining technique. The results reveal that the mean transformed absorbance ratio (male:female) with a 547 nm interference band filter for the two specific segments of the X chromosome is close to 0.5, while for a specific segment of an autosome it is close to 1.0, in the two sets of control; namely, the positive control (no treatment) and the negative control (treated with 1 M-urea+2M-NaCl) as well as in the reconstituted chromosomal preparations, which received 1 M-urea+2M-NaCl and the NHCP isolated from D. melanogaster. In contrast, the transformed absorbance ratios (male:female) with a 433 nm interference band filter yielded an interestingly different result. The ratios with a 433 nm filter for the X chromosome segments are significantly greater than 0.5 in all three sets of experiments. This finding by itself suggests that the NHCP binding affinity is dissimilar for the X chromosomes of male and female. When the 433 to 547 nm absorbance ratios were compared among the three sets, the data clearly revealed that in both positive control and NHCP reconstituted samples, the absorbance ratios (i.e. 433:547 nm) are significantly different between X chromosomes from males and those from females, while they are different between autosomes from males and females. The ratios are also not significantly different between male and female, either for the X chromosome or for the autosome in the negative control. These findings, therefore, suggest that there is a stronger binding affinity of NHCP for the male X chromosome of Drosophila, and reinstate the view that the X-chromosomal hyperactivity in male Drosophila is the consequence of a regulated organizational change in the DNA template.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Drosophila melanogaster/genética , Cromatina Sexual/metabolismo , Cromossomo X/metabolismo , Animais , Citofotometria , Feminino , Masculino , Ligação Proteica , Transformação Genética
13.
J Cell Sci ; 81: 267-81, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3733896

RESUMO

In the present investigation the transcription and replication patterns have been examined in different segments of the X chromosome and in certain specific segments (88B-92A) of an autosomal segmental hyperploid in which an extra segment 88B-92A (3R) is translocated to the X chromosome in addition to the normal two doses. Transcriptive activity monitored by [3H]uridine-labelling of these autosomal hyperploids reveals an enhanced hyperactivity of the male X chromosome while the female X chromosomes show no change in their activity. [3H]thymidine autoradiograms reveal that while the labelling frequencies of most replicating sites are distinctly lowered in the autosomal hyperploid males, no change within sexes is resolvable with regard to labelling-intensity profile. Furthermore, the X-autosome labelling frequency relation shows a distinct deviation from linearity, suggesting multiple events that lead to a higher template form of the X chromosome. These findings lead us to suggest that the signals emanating from autosome(s) do not interfere with the primary modulation inherent in the X chromosome, but act on a modulated organization of the same at a second step evoking higher activity in the male X chromosome. The results further reveal that the gene activity of the X chromosome remains unaffected by the pattern of pairing of the autosomal segments.


Assuntos
Replicação do DNA , Transcrição Gênica , Cromossomo X/fisiologia , Animais , Drosophila , Masculino , Microscopia Eletrônica
14.
J Cell Sci ; 65: 95-109, 1984 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6715430

RESUMO

DNA replication in the polytene chromosomes of larval salivary glands of Drosophila hydei has been examined under normal physiological conditions, with or without puromycin, by an autoradiographic procedure using [3H]thymidine. It has been demonstrated that puromycin induces new labelling patterns that can be identified as initiation patterns. Such initiation patterns were found to have been induced during both the initial (interband labelling patterns) and the terminal (discontinuous) phases. Both induced patterns are sensitive to alpha-amanitin. These findings lead us to suggest that (a) the puff-interband-labelled patterns are indeed the initial patterns, and (b) the induction of new initiation, which is normally known to be prevented until the completion of the cycle, can be brought about by puromycin. The results also suggest the probable existence of a pool of protein factor(s) for the initiation of a replication cycle already present in the cell system.


Assuntos
Replicação do DNA/efeitos dos fármacos , Puromicina/farmacologia , Amanitinas/farmacologia , Animais , Autorradiografia , Cromossomos/metabolismo , Cromossomos/ultraestrutura , Drosophila , Feminino , Heterocromatina/biossíntese , Masculino , Glândulas Salivares/efeitos dos fármacos , Glândulas Salivares/metabolismo , Glândulas Salivares/ultraestrutura , Timidina/metabolismo , Cromossomo X/metabolismo , Cromossomo X/ultraestrutura
20.
J Cell Sci ; 47: 295-309, 1981 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7263783

RESUMO

The results of examination of the template activity of the fixed polytene chromosomes of Drosophila hydei, monitored by 3H-UTP, under in situ assay conditions, upon the use of endogenous Drosophila polymerase, exogenous Escherichia coli RNA polymerase (holoenzyme) and exogenous Drosophila RNA polymerase II (or B) have been presented. Analysis of the data reveals that the transcription patterns with the 3 enzymes are not strictly comparable with the pattern obtained under in vivo conditions. Yet, with each of the 3 conditions of assay, there is a reasonable concordance between the template activity on the single X chromosome of the male and the paired Xs of the female, as observed under in vivo. There is also, in every case, a high positive correlation between the 3H-UMP incorporation into the X chromosome and that into a specific autosome. A site-wise analysis of 3H-UMP labelling under the 3 assay conditions also reveals that for most of the regions, the sites which are highly active in vivo also show high labelling in situ, and the proportionally is maintained in both sexes. These result have been interpreted to have suggested that the hyperactivity of the male X vis-a-vis dosage compensation in Drosophila is primarily a property of the inherent organization of the X chromosome itself and is achieved through modulation in the organization, rather than exclusively through autosomal factor(s), although a secondary level of autosomal regulation has not yet been ruled out.


Assuntos
Drosophila/genética , Cromossomos Sexuais/fisiologia , Transcrição Gênica , Cromossomo X/fisiologia , Animais , Autorradiografia , Cromatina/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Drosophila/enzimologia , Feminino , Masculino , Especificidade da Espécie , Moldes Genéticos
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