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2.
Praxis (Bern 1994) ; 91(45): 1900-8, 2002 Nov 06.
Artigo em Alemão | MEDLINE | ID: mdl-12462892

RESUMO

The aim of the present study was to investigate the effectiveness of an inpatient rehabilitation program and outpatient physiotherapy, respectively. Moreover, we wanted to know whether the referral to these two treatment paths was appropriate with regard to the patient's initial health status. According to the referring physician's indication patients with health problems in the cervical, lumbar spine, arm or leg were treated by an inpatient rehabilitation program or by outpatient physiotherapy. These two consecutively recruited patient cohorts were then compared. Those patients treated by the inpatient rehabilitation program differed from the outpatient group with regard to the initial health status and to age. Patients with musculoskeletal problems, who underwent an inpatient rehabilitation program, showed a significantly worse health and functional status than the outpatient group. Therefore, it can be concluded that the indication towards inpatient rehabilitation or outpatient physiotherapy was correctly given by the referring physicians. Patients treated by outpatient physiotherapy did also show a reduced health and functional status in comparison to the average population. Both types of treatment led to statistically significant and clinically relevant improvement of both the health and functional status in all patient groups.


Assuntos
Assistência Ambulatorial , Doenças Musculoesqueléticas/reabilitação , Admissão do Paciente , Encaminhamento e Consulta , Adulto , Idoso , Avaliação da Deficiência , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Equipe de Assistência ao Paciente , Centros de Reabilitação , Suíça
3.
Br J Cancer ; 86(8): 1290-6, 2002 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-11953887

RESUMO

The genesis of hepatocellular carcinoma is promoted by changes in the regulatory MDM2-P14ARF system. The incidence of such changes has to date not been analysed in non-tumourous livers showing regenerative proliferation. In the present study, 24 cirrhotic livers of alcohol-, autoimmue disorder- or HCV-caused genesis were screened for MDM2-P14ARF alterations at the level of protein, DNA and mRNA. Using confocal laser scanning microscopy, the absence of MDM2 and P14ARF expression was detected in all samples except three HCV-infected livers (four livers) which contained hepatocytes overexpressing MDM2 (P14ARF) protein. In two of the samples lacking P14ARF expression, laser microdissection and PCR demonstrated deletion of the P14ARF gene. The P14ARF gene amplified from other specimens did not carry mutations. MDM2 splicing variants were present in tissues from alcohol- and autoimmune disorder-induced cirrhoses. Sequencing of full-size mRNA revealed a MDM2 mis-sense mutation in an alcohol-induced cirrhosis. One sample contained regenerative nodules with genetic instability occurring at MDM2 locus D12S83 according to the data of automatic PCR fragment analysis. In summary, this study gives first evidence for different types of MDM2 and P14ARF alterations in cirrhotic livers. We suggest that the changes impair the regulatory MDM2-P14ARF system, thus possibly favouring regenerative proliferation and transformation.


Assuntos
Cirrose Hepática/genética , Cirrose Hepática/patologia , Mutação/genética , Proteínas Nucleares , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p14ARF/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Sequência de Bases , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Masculino , Repetições de Microssatélites/genética , Prognóstico , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2 , Splicing de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p14ARF/metabolismo
4.
Front Biosci ; 7: f8-9, 2002 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11779711

RESUMO

We present a 3D-model of apoptotic nuclei of HL-60 cells treated with 10 g/ml Etoposide (topoisomerase II inhibitor) for 24 hours. The static model was generated from a series of optical sections obtained through a confocal microscope by freeware and shareware graphical programs available in the Internet. Its animation was done by 3D Studio Max. We demonstrate the appearance of typical fragmentation and condensation of chromatin accompanied by its aggregation to the inner side of the nuclear membrane.


Assuntos
Apoptose , Núcleo Celular/patologia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Linhagem Celular , Células HL-60/patologia , Humanos
5.
Mol Biol Cell ; 12(12): 3904-18, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11739789

RESUMO

The nucleolus is a ubiquitous, mostly spheroidal nuclear structure of all protein-synthesizing cells, with a well-defined functional compartmentalization. Although a number of nonribosomal proteins involved in ribosome formation have been identified, the elements responsible for the shape and internal architecture of nucleoli are still largely unknown. Here, we report the molecular characterization of a novel protein, NO145, which is a major and specific component of a nucleolar cortical skeleton resistant to high salt buffers. The amino acid sequence of this polypeptide with a SDS-PAGE mobility corresponding to M(r) 145,000 has been deduced from a cDNA clone isolated from a Xenopus laevis ovary expression library and defines a polypeptide of 977 amino acids with a calculated mass of 111 kDa, with partial sequence homology to a synaptonemal complex protein, SCP2. Antibodies specific for this protein have allowed its recognition in immunoblots of karyoskeleton-containing fractions of oocytes from different Xenopus species and have revealed its presence in all stages of oogenesis, followed by a specific and rapid degradation during egg formation. Immunolocalization studies at the light and electron microscopic level have shown that protein NO145 is exclusively located in a cage-like cortical structure around the entire nucleolus, consisting of a meshwork of patches and filaments that dissociates upon reduction of divalent cations. We propose that protein NO145 contributes to the assembly of a karyoskeletal structure specific for the nucleolar cortex of the extrachromosomal nucleoli of Xenopus oocytes, and we discuss the possibility that a similar structure is present in other cells and species.


Assuntos
Nucléolo Celular/metabolismo , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Proteínas de Xenopus/química , Proteínas de Xenopus/metabolismo , Xenopus laevis , Sequência de Aminoácidos , Animais , Nucléolo Celular/química , Nucléolo Celular/ultraestrutura , Clonagem Molecular , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/ultraestrutura , Espectrometria de Massas , Microscopia Confocal , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Oócitos/ultraestrutura , Oogênese , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Homologia de Sequência de Aminoácidos , Proteínas de Xenopus/genética , Proteínas de Xenopus/ultraestrutura , Xenopus laevis/genética
6.
Ther Umsch ; 58(8): 509-14, 2001 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-11552359

RESUMO

Physiotherapy plays a significant role in the treatment of sport injuries and can be especially adapted for this purpose. The physiotherapist has two tasks: 1. As a therapist treating a well defined pathologic entity or functional deficit. 2. Instructing the patient in further self-treatment and appropriate measures, behavioral changes and preventive approaches. The therapeutic emphasis is presented in seven interdependent groups: pain/swelling, flexibility, strength, coordination, endurance, psychological measures, preventive measures. The aim of treatment is to resume training activities. For each group there is a description of clinical symptoms, diagnosis according to functional tests and recommended treatment measures. The therapy group(s) and their priorities should be listed when making an individual therapeutic decision.


Assuntos
Traumatismos em Atletas/prevenção & controle , Traumatismos em Atletas/reabilitação , Modalidades de Fisioterapia/métodos , Prevenção de Acidentes , Traumatismos em Atletas/epidemiologia , Terapia por Exercício/métodos , Humanos , Aptidão Física
7.
Cancer Lett ; 171(2): 153-64, 2001 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11520599

RESUMO

Random peptide phage display libraries have been employed widely to identify protein-protein interactions, using as targets either purified proteins, intact cells, or organs. To isolate peptides that bind to human neuroblastoma cells, we have used a phage display approach with the neuroblastoma cell line WAC 2 as the target. In particular, two bacteriophages, t147 and t160, displaying peptides p147 and p160, respectively, were isolated by repeated display cycles. Binding of t147 and t160 to WAC 2 cells was abrogated by pretreatment with the peptides p147 and p160, respectively, which strongly support that cellular binding of both phages is dictated by their displayed peptides. Immunofluorescence analysis by confocal light microscopy revealed that the major proportion of t147 remains on the surface of WAC 2 cells and that only a fraction is taken up into the cells. In contrast, the vast majority of t160 is internalized. K(+) depletion reduced the number of the phages internalized by the cells to approximately 20% for t160 and to 10% for t147, indicating that the phage internalization was through receptor-mediated endocytosis. Phage t147 appears to bind to a range of tumor cell lines, including neuroblastoma, breast cancer, glioblastoma and C-cell carcinoma, but less so to non-tumor lines, such as erythrocytes, lymphocytes, monocytes and epithelial cells. Phage t160 bound to a range of neuroblastoma cell lines and a breast cancer cell line, but not to other tested cell lines. While neither of the displayed peptides conferred a narrow tissue specific binding ability, they do provide a basis for targeted drug delivery in selected experimental or natural tumor systems.


Assuntos
Neuroblastoma/metabolismo , Oligopeptídeos/metabolismo , Biblioteca de Peptídeos , Sequência de Aminoácidos , Bacteriófagos/metabolismo , Ligação Competitiva , Endocitose , Humanos , Oligopeptídeos/isolamento & purificação , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Homologia de Sequência de Aminoácidos , Especificidade por Substrato , Células Tumorais Cultivadas
8.
Ther Umsch ; 58(4): 213-9, 2001 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-11344952

RESUMO

In order to tolerate the exertion in fitness exercise in the long term a sufficiently strong trunk musculature should be aimed at. In order to stabilize and balance the trunk and the pelvis there should be an optimal interaction of the muscles of the abdomen, the lateral trunk, the back and the flexors and extensors of the hip. If that balance is disrupted, muscular imbalance and a weakening or shortening of the muscles involved can occur. That imbalance leads to inadequate and excessive strain of the functional system of spine and pelvis. The functional anatomy of the trunk is described with clinical references in order to elucidate this context. A program of strength and stretching exercises for the trunk is presented suited to the needs of those practicing fitness exercise.


Assuntos
Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Músculo Esquelético/fisiologia , Aptidão Física , Humanos , Contração Muscular/fisiologia , Fadiga Muscular/fisiologia
9.
Hepatology ; 32(6): 1317-28, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11093739

RESUMO

The Dubin-Johnson syndrome is an inherited disorder characterized by conjugated hyperbilirubinemia. The deficient hepatobiliary transport of anionic conjugates is caused by the absence of a functional multidrug-resistance protein 2 (MRP2, symbol ABCC2) from the apical (canalicular) membrane of hepatocytes. Mechanisms underlying this deficiency may include rapid degradation of mutated MRP2 messenger RNA (mRNA) or impaired MRP2 protein maturation and trafficking. We investigated the consequences of the mutation MRP2Delta(R,M), which leads to the loss of 2 amino acids from the second ATP-binding domain of MRP2. The MRP2Delta(R,M) mutation is associated with the absence of the MRP2 glycoprotein from the apical membrane of hepatocytes. Transfection of mutated MRP2 complementary DNA (cDNA) led to an MRP2Delta(R,M) protein that was only core glycosylated, sensitive to endoglycosidase H digestion, and located in the endoplasmic reticulum (ER) of transfected HEK293 and HepG2 cells. This indicated that deletion of Arg1392 and Met1393 leads to impaired maturation and trafficking of the protein from the ER to the Golgi complex. Inhibition of proteasome function resulted in a paranuclear accumulation of the MRP2Delta(R,M) protein, suggesting that proteasomes are involved in the degradation of the mutant protein. This is the first mutation in Dubin-Johnson syndrome shown to cause deficient MRP2 maturation and impaired sorting of this glycoprotein to the apical membrane.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Deleção de Genes , Icterícia Idiopática Crônica/genética , Icterícia Idiopática Crônica/metabolismo , Proteínas de Membrana Transportadoras , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Processamento de Proteína Pós-Traducional , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Sequência de Aminoácidos/genética , Linhagem Celular/metabolismo , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Cisteína Endopeptidases/fisiologia , Imunofluorescência , Proteínas de Fluorescência Verde , Hepatócitos/metabolismo , Hepatócitos/ultraestrutura , Humanos , Indicadores e Reagentes , Leupeptinas/farmacologia , Proteínas Luminescentes , Microscopia Confocal , Microscopia Imunoeletrônica , Dados de Sequência Molecular , Proteína 2 Associada à Farmacorresistência Múltipla , Complexos Multienzimáticos/antagonistas & inibidores , Complexos Multienzimáticos/fisiologia , Mutação/genética , Complexo de Endopeptidases do Proteassoma , Distribuição Tecidual
10.
Eur J Cell Biol ; 78(11): 767-78, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10604653

RESUMO

Using immunoblotting, immunprecipitation with subsequent fragment mass spectrometry, and immunolocalization techniques, we have detected the actin-binding ca. 120-kDa protein drebrin, originally identified in - and thought to be specific for - neuronal cells, in diverse kinds of human and bovine non-neuronal cells. Drebrin has been found in numerous cell culture lines and in many tissues of epithelial, endothelial, smooth muscle and neural origin but not in, for example, cardiac, skeletal and certain types of smooth muscle cells, in hepatocytes and in the human epithelium-derived cell culture line A-431. By double-label fluorescence microscopy we have found drebrin enriched in actin microfilament bundles associated with plaques of cell-cell contact sites representing adhering junctions. These drebrin-positive, adhering junction-associated bundles, however, are not identical with the vinculin-containing, junction-attached bundles, and in the same cell both subtypes of microfilament-anchoring plaques are readily distinguished by immunolocalization comparing drebrin and vinculin. The intracellular distribution of the drebrin- and the vinculin-based microfilament systems has been studied in detail by confocal fluorescence laser scanning microscopy in monolayers of the polar epithelial cell lines, MCF-7 and PLC, and drebrin has been found to be totally and selectively absent in the notoriously vinculin-rich focal adhesions. The occurrence and the possible functions of drebrin in non-neuronal cells, notably epithelial cells, and the significance of the existence of two different actin-anchoring junctional plaques is discussed.


Assuntos
Citoesqueleto de Actina/química , Actinas/análise , Neuropeptídeos/análise , Anticorpos Monoclonais/análise , Ácido Edético/análise , Eletroforese em Gel de Poliacrilamida , Endotélio Vascular/citologia , Células Epiteliais , Humanos , Immunoblotting , Imuno-Histoquímica , Microscopia Confocal , Polivinil/análise , Testes de Precipitina , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Compostos de Tosil/análise , Vinculina/análise
11.
J Biol Chem ; 274(45): 32122-6, 1999 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-10542247

RESUMO

Alkylation treatment of HeLa cells results in the rapid induction of apoptosis as revealed by DNA laddering and cleavage of poly(ADP-ribose) polymerase (PARP) into the 29-and 85-kDa fragments (Kumari S. R., Mendoza-Alvarez, H. & Alvarez-Gonzalez, R. (1998) Cancer Res. 58, 5075-5078). Here, we performed a time-course analysis of (i) poly(ADP-ribose) synthesis and degradation as well as (ii) the subnuclear localization of PARP and its fragments by using confocal laser scanning immunofluorescence microscopy. PARP was activated within 15 min post-treatment, as revealed by nuclear immunostaining with antibody 10H (recognizing poly(ADP-ribose)). This was followed by a late, time-dependent, progressive decline of 10H signals that coincide with the time of PARP cleavage. Strikingly, nucleolar immunostaining with antibodies 10H and C-II-10 (recognizing the 85-kDa PARP fragment) was lost by 15 min post-treatment, whereas F-I-23 signals (recognizing the 29-kDa fragment) persisted. We hypothesize that the 85-kDa PARP fragment is translocated, along with covalently bound poly(ADP-ribose), from nucleoli to the nucleoplasm, whereas the 29-kDa fragment is retained, because it binds to DNA strand breaks. Our data (i) provide a link between the known time-dependent bifunctional role of PARP in apoptosis and the subcellular localization of PARP fragments and also (ii) add to the evidence for early proteolytic changes in nucleoli during apoptosis.


Assuntos
Apoptose , Nucléolo Celular/metabolismo , Fragmentos de Peptídeos/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Poli(ADP-Ribose) Polimerases/metabolismo , Alquilação , Dano ao DNA , Células HeLa , Humanos , Peso Molecular , Fatores de Tempo
12.
Ultramicroscopy ; 80(3): 163-82, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10573828

RESUMO

To image the distribution of a specific element in a specimen with an energy filtering TEM, the element-unspecific background under the core-edge has to be subtracted. The most commonly used procedure is the three-window power-law method leading to considerable systematic errors for low-energy core-edges. Here a new method is described which can be considered as a generalized difference method. Characteristic examples for element detection in biological specimens using this method are shown. The background under the core-edge can be described by one or two pre-edge windows as a polynome of third order. This function can be deduced from specimen areas that are not known to contain the element or from a second specimen used as a standard. Control experiments showed that background subtraction for on-overlapping core-edges in the low-loss region (50-200 eV) needs two pre-edge images, whereas at higher-energy losses (> 300 eV) only one pre-edge image is necessary. With the method described, objective elemental mapping becomes possible even for edges at 50-100 eV. This was proven for the M2,3-edge of iron at 60 eV. The detection of phosphorous was possible with a signal-to-noise ratio five times higher than when using the three-window method. Preliminary data showed that it should be possible to detect calcium with only one image before the edge.


Assuntos
Aumento da Imagem/métodos , Microscopia Eletrônica/métodos , Animais , Carbono/análise , DNA de Neoplasias/análise , DNA de Neoplasias/imunologia , Diagnóstico por Imagem , Ferritinas/química , Ferritinas/ultraestrutura , Aumento da Imagem/instrumentação , Imunoglobulina M , Ferro/análise , Microscopia Eletrônica/instrumentação , Células Tumorais Cultivadas , Tymovirus/ultraestrutura
13.
J Am Soc Nephrol ; 10(6): 1159-69, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10361853

RESUMO

Human kidney proximal tubule epithelia express the ATP-dependent export pump for anionic conjugates encoded by the MRP2 (cMRP/cMOAT) gene (symbol ABCC2). MRP2, the apical isoform of the multidrug resistance protein, is an integral membrane glycoprotein with a molecular mass of approximately 190 kD that was originally cloned from liver and localized to the canalicular (apical) membrane domain of hepatocytes. In this study, MRP2 was detected in human kidney cortex by reverse transcription-PCR followed by sequencing of a 826-bp cDNA fragment and by immunoblotting using two different antibodies. Human MRP2 was localized to the apical brush-border membrane domain of proximal tubules by double and triple immunofluorescence microscopy including laser scanning microscopy. The expression of MRP2 in renal cell carcinoma was studied by reverse transcription-PCR and immunoblotting in samples from patients undergoing tumor-nephrectomy without prior chemotherapy. Clear-cell carcinomas, originating from the proximal tubule epithelium, expressed MRP2 in 95% (18 of 19) of cases. Immunofluorescence microscopy of MRP2 in clear-cell carcinoma showed a lack of a distinct apical-to-basolateral tumor cell polarity and an additional localization of MRP2 on intracellular membranes. MRP2, the first cloned ATP-dependent export pump for anionic conjugates detected in human kidney, may be involved in renal excretion of various anionic endogenous substances, xenobiotics, and cytotoxic drugs. This conjugate-transporting ATPase encoded by the MRP2 gene has a similar substrate specificity as the multidrug resistance protein MRP1, and may contribute to the multidrug resistance of renal clear-cell carcinomas.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/isolamento & purificação , Carcinoma de Células Renais/genética , Genes MDR/genética , Neoplasias Renais/genética , Túbulos Renais Proximais/química , Proteínas de Membrana Transportadoras , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Carcinoma de Células Renais/química , Células Clonais , Dipeptidil Peptidase 4/análise , Expressão Gênica , Marcadores Genéticos , Humanos , Immunoblotting , Neoplasias Renais/química , Microscopia de Fluorescência , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína 2 Associada à Farmacorresistência Múltipla , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Neoplásico/análise , Valores de Referência , Sensibilidade e Especificidade
14.
Mol Pharmacol ; 55(5): 929-37, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10220572

RESUMO

The multidrug resistance protein MRP1 functions as an ATP-dependent conjugate export pump and confers multidrug resistance. We cloned MRP2 (symbol ABCC2), a MRP family member localized to the apical membrane of polarized cells. Stable expression of MRP2 in transfected human embryonic kidney (HEK-293) and Madin-Darby canine kidney (MDCK) cells was enhanced by inhibitors of histone deacetylase. In polarized MDCK cells, both rat and human MRP2 were sorted to the apical plasma membrane. An antibody raised against the amino terminus of rat MRP2 recognized the recombinant protein on the apical surface of nonpermeabilized cells, providing direct evidence for the extracellular localization of the amino terminus of MRP2. ATP-dependent transport by recombinant human and rat MRP2 was measured with membrane vesicles from stably transfected cells. The Km value of human MRP2 was 1.0 +/- 0.1 microM for leukotriene C4 and 7.2 +/- 0.7 microM for 17beta-glucuronosyl estradiol; the Km values of human MRP1 were 0.1 +/- 0.02 microM for leukotriene C4 and 1.5 +/- 0.3 microM for 17beta-glucoronosyl estradiol. Thus, the conjugate-transporting ATPases MRP2 and MRP1 differ not only by their domain-specific localization but also by their kinetic properties. Drug resistance conferred by recombinant MRP2 was studied in MDCK and HEK-293 cells using cell viability assays. Expression of human and rat MRP2 enhanced the resistance of MDCK cells to etoposide 5.0-fold and 3.8-fold and to vincristine 2.3- and 6.0-fold, respectively. Buthionine sulfoximine reduced resistance to these drugs. Human MRP2 overexpressed in HEK-293 cells enhanced the resistance to etoposide (4-fold), cisplatin (10-fold), doxorubicin (7.8-fold), and epirubicin (5-fold). These results demonstrate that MRP2 confers resistance to cytotoxic drugs.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Trifosfato de Adenosina/fisiologia , Resistência a Múltiplos Medicamentos/genética , Proteínas de Membrana Transportadoras , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Subfamília B de Transportador de Cassetes de Ligação de ATP/fisiologia , Animais , Antineoplásicos/farmacocinética , Transporte Biológico/fisiologia , Divisão Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Clonagem Molecular , Cães , Humanos , Dados de Sequência Molecular , Proteína 2 Associada à Farmacorresistência Múltipla , Transfecção
15.
Scand J Rehabil Med ; 30(4): 211-9, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9825385

RESUMO

In this multicentre intervention study, we compared an integrated group treatment program which combines psychological and education methods into a more active training approach, with the traditional individual approach of physiotherapy and physical procedures for sub-chronic and chronic low back pain. Our 411 patients had a 4-week inpatient treatment: 243 patients in an experimental program and 168 in a traditional program. Outcomes of 283 patients were assessed 3 months and 1 year after entry. The dropout rate was 31.1%. Both conditions demonstrated favourable initial effects on functional and psychological parameters, but the integrated approach showed better long-term results for work rehabilitation than the traditional approach. The most successful patients (n = 58) were younger and had a higher educational level in comparison to the unsuccessful subgroup (n = 71). The main conclusion is that an integrated approach promoting self control and behaviour change through educational measures achieves better long-term results than the traditional individual physiotherapy approach.


Assuntos
Terapia por Exercício , Dor Lombar/reabilitação , Educação de Pacientes como Assunto , Adulto , Doença Crônica , Escolaridade , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Pacientes Internados , Masculino , Suíça , Resultado do Tratamento
16.
Eur J Cell Biol ; 74(3): 294-301, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9402478

RESUMO

Cathepsins B and L are catabolic lysosomal enzymes but are likely candidates for extracellular proteolysis in normal and malignant processes. The signal mediator 12(S)-HETE selectively triggers a shot-gun release of cathepsin B. We have therefore investigated the intracellular distribution of cathepsins in unstimulated and 12(S)-HETE-stimulated tumor cells. Cathepsins B and L have only limited colocalization, which is found in the regions of synthesis and sorting (endoplasmic reticulum, Golgi, trans Golgi network). Treatment by 12(S)-HETE scatters cathepsin B but not cathepsin L and proform of cathepsin B. Colocalization with both mannose 6-phosphate receptors is very limited for both cathepsins. But extensive colocalization of cathepsin B and the endosomal/lysosomal marker CD63 (LIMP-I) documents the main fraction of the enzyme in these compartments. The supposed non-lysosomal fraction of cathepsin B is very likely the secretable material which follows a regulated secretory pathway. Storage and regulated secretion in tumor cells support extracellular proteolysis as a means in invasion which may lead to metastasis. But the mechanisms by which cells might acquire and eventually apply this means is still unknown.


Assuntos
Ácido 12-Hidroxi-5,8,10,14-Eicosatetraenoico/farmacologia , Catepsina B/metabolismo , Catepsinas/metabolismo , Endopeptidases , Antígenos CD/metabolismo , Transporte Biológico/efeitos dos fármacos , Catepsina L , Cisteína Endopeptidases , Endossomos/metabolismo , Humanos , Neoplasias Pulmonares , Lisossomos/metabolismo , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Glicoproteínas da Membrana de Plaquetas/metabolismo , Precursores de Proteínas/metabolismo , Receptor IGF Tipo 2/metabolismo , Tetraspanina 30 , Células Tumorais Cultivadas
17.
Chromosoma ; 105(7-8): 418-30, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9211969

RESUMO

Recently, it was shown that a short exposure of living mammalian cells to low ionic strength buffers (hypotonic shock) caused partial or almost complete unraveling of interphase nucleoli. However, when the cells were released from the hypotonic shock and transferred to normal isotonic medium, functionally active and structurally integral nucleoli were reassembled at their initial positions within interphase nuclei. Here, we show further that this process is accompanied by the appearance of numerous discrete extranucleolar bodies, which have striking similarities to the prenucleolar bodies (PNBs) observed in untreated cells at telophase of mitosis. (1) Like PNBs at mitosis, hypotonically induced interphase PNBs are composed of RNA-positive granules and fibrils, contain the major nucleolar protein B23 and silver-binding proteins, but lack DNA and RNA polymerase I transcription factor UBF. (2) As for mitotic PNBs, disappearance of the interphase PNB counterparts coincides with the increase in size of reconstructed nucleoli. (3) Addition of actinomycin D does not prevent assembly of interphase PNBs, but does arrest their coalescence with the chromosomal nucleolus-organizing regions and blocks the complete reformation of nucleoli. It is concluded that the assembly of PNBs generally observed at telophase of mitosis can be induced experimentally in nuclei of interphase mammalian cells in vivo. At interphase, this process is probably initiated by changes in the intracellular ionic environment.


Assuntos
Nucléolo Celular/fisiologia , Nucléolo Celular/ultraestrutura , Interfase/fisiologia , Mitose/fisiologia , Proteínas Pol1 do Complexo de Iniciação de Transcrição , Telófase/fisiologia , Animais , Nucléolo Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura/química , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Dactinomicina/farmacologia , Células HeLa/efeitos dos fármacos , Humanos , Soluções Hipotônicas/farmacologia , Immunoblotting , Imuno-Histoquímica , Microscopia , Microscopia Eletrônica , Proteínas Nucleares/imunologia , Proteínas Nucleares/metabolismo , Inibidores da Síntese de Ácido Nucleico/farmacologia , Concentração Osmolar , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Telófase/efeitos dos fármacos , Fatores de Transcrição/imunologia , Fatores de Transcrição/metabolismo
18.
Exp Cell Res ; 233(1): 155-68, 1997 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-9184085

RESUMO

In order to determine the most persistent components of the nucleolus that might serve as "core" nucleolar elements, we studied the reactivity of nucleoli in living mammalian cells subjected to hypotonic buffer saline followed by the incubation of the cells in an isotonic medium. To document as precisely as possible the fine structural changes which occurred, the cells were examined by video-enhanced optical microscopy, fluorescence confocal laser scanning microscopy, and electron microscopy combined with cytochemistry. Light microscopic autoradiography was used to demonstrate the transcriptional characteristics of the reassembled nucleoli. It was shown that all the major compartments of the intact nucleolus could be substantially affected by reduction of the osmolarity of the environmental media. The dynamic events of the nucleolar unraveling in low-salt buffers occurred in the following order: dispersion of the nucleolar pars granulosa, disassociation of the fibrillar complexes into discrete fibrillar centers (FCs) and the dense fibrillar component (DFC), and the almost complete unraveling of the DFC and FCs. At the terminal stages of nucleolar dispersion, the nuclear interior was mainly composed of a loose filamentous meshwork, and none of the typically discerned nucleolar constituents was recognized. Nevertheless, when hypotonically treated cells were returned to isotonic conditions, the nucleolar bodies rapidly began to reassemble. Within 1-2 h of cell incubation under isotonicity, the nucleoli not only became clearly visible, but also reconstituted to their initial size, shape, and position within the nucleus. The ultrastructure and functional activity of the reassembled nucleoli were also found to be fully comparable to those of the untreated controls. These data indicate that the architectural composition of the interphase nucleolus is strictly controlled by the cell. As far as could be determined, none of the usual substructures of the intact nucleolus that could be substituted by complete reassembly of the nucleolar bodies in normotonic conditions, including FCs and the DFC, remained clearly preserved in the terminal stage of nucleolar unraveling. We concluded that the integrity of the nucleolus was mainly preserved by the nuclear or nucleolar matrix system rather than by any other nucleolar structural domains.


Assuntos
Nucléolo Celular/fisiologia , Nucléolo Celular/ultraestrutura , Corantes de Rosanilina , Animais , Células Cultivadas , Proteínas Cromossômicas não Histona/isolamento & purificação , Corantes , DNA/isolamento & purificação , Imunofluorescência , Rim/citologia , Microscopia Confocal , Microscopia Eletrônica , Microscopia de Interferência , Microscopia de Vídeo , Concentração Osmolar , Suínos , Uridina/metabolismo
19.
J Struct Biol ; 118(1): 43-61, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9087914

RESUMO

The purpose of this metholdological survey was to find optimal methods for the fixation and demonstration of glycosaminoglycans, mainly hyaluronan, and proteoglycans, in subepidermal extracellular matrix (ECM) regions of axolotl embryos. We compared living ECM in the laser-scanning microscope (LSM) with chemically fixed or cryoimmobilized extracellular matrix in the transmission (TEM) and scanning electron microscope (SEM). The gel-like structure of living extracellular matrix in the LSM undoubtedly provides the most natural state, whereas shrinkage of the extracellular matrix occurs during conventional fixation and dehydration for TEM or SEM. Among the methods used for fixation and processing of subepidermal extracellular matrices for SEM, plunge-freezing/freeze-drying is to be preferred. Still more satisfying, however, are results obtained with high-pressure frozen/freeze-substituted ECM material in the TEM, for which 10% polyvinyl pyrrolidon +7% methanol was used as a cryoprotectant before high-pressure freezing. In these specimens, no freeze-damage could be observed and they could be regarded as adequately frozen. Conversely, the yield in adequately frozen specimens without cryoprotection was insufficient. In these specimens, the ECM contained honeycomb-like structures which, in the current literature, are regarded as hyaluronan.


Assuntos
Ambystoma/embriologia , Criopreservação/métodos , Matriz Extracelular/ultraestrutura , Ácido Hialurônico/análise , Microscopia Eletrônica de Varredura/métodos , Microscopia Eletrônica/métodos , Proteoglicanas/análise , Animais , Embrião não Mamífero/química , Embrião não Mamífero/ultraestrutura , Epiderme/embriologia , Epiderme/ultraestrutura , Matriz Extracelular/química , Liofilização , Larva/química , Larva/ultraestrutura , Metanol , Morfogênese , Povidona/análogos & derivados , Pressão , Manejo de Espécimes
20.
J Microsc ; 188(Pt 2): 125-35, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9418270

RESUMO

Transmission X-ray microscopy makes it possible to investigate biological specimens, i.e. cells and organelles, in their natural wet environment. The main processes determining the contrast in X-ray microscopy are photoelectric absorption and phase shift. X-ray microscopic experiments can therefore be carried out in both amplitude and phase contrast. The Göttingen X-ray microscope at the BESSY storage ring in Berlin is described. PtK2 cells were examined during different stages of the cell cycle. All major constituents of the mitotic apparatus, e.g. chromosomes, centromeres, microtubules and centrosomes, could be visualized, as well as the main structural compartments and organelles of the interphase cell, e.g. nuclear membrane, interphase chromatin, nucleolus and cytoplasmic mitochondria, as well as parts of the cytoskeletal apparatus. In this way new information can be obtained with regard to the ultrastructure of the constituents of intact and unstained cells at a resolution which bridges the gap between light microscopy and electron microscopy. The prospects for the future application of transmission X-ray microscopy in biomedical research are discussed.


Assuntos
Microscopia/métodos , Animais , Ciclo Celular , Técnicas de Cultura , Macropodidae , Raios X
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