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1.
Biomed Tech (Berl) ; 69(2): 125-140, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37935217

RESUMO

OBJECTIVES: To design and develop an approach named HC + SMA-SSA scheme for classifying motor imagery task. METHODS: The offered model employs a new method for classifying motor imagery task. Initially, down sampling is deployed to pre-process the incoming signal. Subsequently, "Modified Stockwell Transform (ST) and common spatial pattern (CSP) based features are extracted". Then, optimal channel selection is made by a novel hybrid optimization model named as Spider Monkey Assisted SSA (SMA-SSA). Here, "Long Short Term Memory (LSTM) and Bidirectional Gated Recurrent Unit (BI-GRU)" models are used for final classification, whose outcomes are averaged at the end. At last, the improvement of SMA-SSA based model is proven over different metrics. RESULTS: A superior sensitivity of 0.939 is noted for HC + SMA-SSA that was higher over HC with no optimization and proposed with traditional ST. CONCLUSIONS: The proposed method achieved effective classification performance in terms of performance measures.


Assuntos
Interfaces Cérebro-Computador , Aprendizado Profundo , Eletroencefalografia/métodos , Imaginação , Algoritmos , Processamento de Sinais Assistido por Computador
2.
J Cancer Res Ther ; 12(1): 126-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27072224

RESUMO

BACKGROUND: Oral submucous fibrosis (OSMF) is one of the most common premalignant conditions in Indian subcontinent due to the traditional use of Areca nut and its various preparations. The genetic predisposition has also been reported in its etiopathogenesis. The rate of malignant transformation is between 7% to 14%. AIM: To evaluate whether ABO blood group is related to OSMF risk. SUBJECTS AND METHODS: It was a cross-sectional hospital-based study. A convenient sample of 164 study subjects constituted the cases and 180 subjects constituted the comparison group. STATISTICAL ANALYSIS USED: The results were analyzed using chi-square test and odds ratio. RESULTS: The chi-square analysis could not establish any significant relationship between OSMF and ABO blood group. But, when the strength of the association was measured using odds ratio, subjects with blood group A had 1.181 times higher risk of developing OSMF in comparison to other groups. CONCLUSION: The subjects with blood group A were at higher risk of developing OSMF in comparison to others. By performing blood group determination using a routine method at outreach programs, the susceptible individuals can be identified and counselled to quit the habit, thereby avoiding potential complications.


Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Estudos de Associação Genética , Fibrose Oral Submucosa/genética , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fibrose Oral Submucosa/sangue , Fibrose Oral Submucosa/patologia , Fatores de Risco
3.
Clin Cancer Res ; 20(2): 382-92, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24178621

RESUMO

PURPOSE: Despite advances, there is an urgent need for effective therapeutics for relapsed diffuse large B-cell lymphoma, particularly in elderly patients and primary central nervous system (CNS) lymphoma. Temozolomide (TMZ), an oral DNA-alkylating agent routinely used in the therapy of glioblastoma multiforme, is active in patients with primary CNS lymphoma but the response rates are low. The mechanisms contributing to TMZ resistance are unknown. EXPERIMENTAL DESIGN: We undertook an unbiased and genome-wide approach to understand the genomic methylation and gene expression profiling differences associated with TMZ resistance in diffuse large B-cell lymphoma cell lines and identify mechanisms to overcome TMZ resistance. RESULTS: TMZ was cytotoxic in a subset of diffuse large B-cell lymphoma cell lines, independent of MGMT promoter methylation or protein expression. Using Connectivity Map (CMAP), we identified several compounds capable of reversing the gene expression signature associated with TMZ resistance. The demethylating agent decitabine (DAC) is identified by CMAP as capable of reprogramming gene expression to overcome TMZ resistance. Treatment with DAC led to increased expression of SMAD1, a transcription factor involved in TGF-ß/bone morphogenetic protein (BMP) signaling, previously shown to be epigenetically silenced in resistant diffuse large B-cell lymphoma. In vitro and in vivo treatment with a combination of DAC and TMZ had greater antilymphoma activity than either drug alone, with complete responses in TMZ-resistant diffuse large B-cell lymphoma murine xenograft models. CONCLUSIONS: Integrative genome-wide methylation and gene expression analysis identified novel genes associated with TMZ resistance and demonstrate potent synergy between DAC and TMZ. The evidence from cell line and murine experiments supports prospective investigation of TMZ in combination with demethylating agents in diffuse large B-cell lymphoma.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Genômica , Linfoma Difuso de Grandes Células B/genética , Animais , Antineoplásicos Alquilantes/uso terapêutico , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilação de DNA , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Decitabina , Modelos Animais de Doenças , Sinergismo Farmacológico , Expressão Gênica , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Humanos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Regiões Promotoras Genéticas , Temozolomida , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Indian J Med Microbiol ; 30(3): 323-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22885200

RESUMO

BACKGROUND: Culture filtrate proteins (CFPs) of Mycobacterium tuberculosis are potential vaccine candidates. OBJECTIVE: The aim was to study the influence of iron levels on CFPs and assess the immuno-protective potential of defined antigenic fractions from high (8 µg Fe/mL) and low iron (0.02 µg Fe / mL) cultures of M. tuberculosis. MATERIALS AND METHODS: The CFPs of M. tuberculosis from high (CFP-high) and low (CFP-low) iron conditions were first compared to identify iron-regulated proteins and then fractionated to obtain ten antigen pools (CF-Ags H1- H5 and L1-L5) that were used to assess the immune response of TB patients and normal healthy controls. RESULTS: Iron limitation resulted in the up-regulation of two novel iron-regulated low-molecular-weight proteins Irp-1 (in CF-Ag L4) and Irp-2 (in CF-Ag L5) and repression of two ESAT proteins (identified with monoclonal antibody HYB 76.8). The median stimulation indices (SIs) against most of the CF-Ags were high in pulmonary TB patients. The CF-Ags L1 and L2 showed statistically significant SI (P values of 0.0027 and 0.0029 respectively); the % case recognition was high with these antigens as well as with L4 ( P = 0.0275). IFN-γ in response to these CF-Ags was significantly high in the endemic normals; maximal expression was seen with CF-Ag L5 (median value of 233 pg mL -1 ) that was higher than the corresponding H5 (140 pg mL -1 ) and H3 and L3 (205 and 206 pg mL -1 respectively). CONCLUSIONS: CF-Ags L5, H3 and L3 showed immuno-protective potential in this geographical location.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Linfócitos T/imunologia , Tuberculose/imunologia , Adulto , Antígenos de Bactérias/biossíntese , Proteínas de Bactérias/biossíntese , Feminino , Humanos , Ferro/metabolismo , Masculino , Mycobacterium tuberculosis/metabolismo , Tuberculose/microbiologia
5.
Curr Treat Options Oncol ; 13(1): 82-101, 2012 03.
Artigo em Inglês | MEDLINE | ID: mdl-22297843

RESUMO

OPINION STATEMENT: The standard front-line treatment of Diffuse Large B-Cell Lymphoma (DLBCL) remains Rituximab combined with multi-agent cytotoxic chemotherapy. In spite of high response rates to this therapy, relapsed/refractory disease is observed in up to 40% of patients. It is our opinion that additional chemoimmunotherapy, followed by high-dose therapy with autologous stem cell transplant (HDT-ASCT) for responsive disease, is the optimal therapy for these patients. However, many patients cannot tolerate HDT-ASCT, or have relapsed/refractory disease in spite of it. These patients have a poor overall prognosis, and there is no clear consensus as to how these patients should be treated. Over the past decade, significant advances have been made in the understanding of the molecular genesis and subtyping of DLBCL, leading to the identification of multiple pathways and molecules that can be targeted for clinical benefit. Examples include Bcl-2, Bcl-6, cell surface markers, and myriad molecules in both the B-Cell receptor and PI3K/Akt/mTOR pathways. As agents targeting these molecules and pathways progress from preclinical models to early clinical trials, more is learned about what might predict for response to these agents, such as cell of origin classification, and/or expression of relevant molecular markers, as measured by immunohistochemistry or gene expression profiling. Both the successes and failures of these novel targeted agents promise to dramatically refine, improve, and individualize the classification and treatment of DLBCL. Therefore, it is our opinion that patients with relapsed/refractory DLBCL are an ideal population for clinical trials due to both the lack of standardized treatment, and the recent advancements in pathobiology and early-phase treatment options.

6.
Clin Cancer Res ; 18(9): 2534-44, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22338016

RESUMO

PURPOSE: The mTOR pathway is constitutively activated in diffuse large B-cell lymphoma (DLBCL). mTOR inhibitors have activity in DLBCL, although response rates remain low. We evaluated DLBCL cell lines with differential resistance to the mTOR inhibitor rapamycin: (i) to identify gene expression profile(s) (GEP) associated with resistance to rapamycin, (ii) to understand mechanisms of rapamycin resistance, and (iii) to identify compounds likely to synergize with mTOR inhibitor. EXPERIMENTAL DESIGN: We sought to identify a GEP of mTOR inhibitor resistance by stratification of eight DLBCL cell lines with respect to response to rapamycin. Then, using pathway analysis and connectivity mapping, we sought targets likely accounting for this resistance and compounds likely to overcome it. We then evaluated two compounds thus identified for their potential to synergize with rapamycin in DLBCL and confirmed mechanisms of activity with standard immunoassays. RESULTS: We identified a GEP capable of reliably distinguishing rapamycin-resistant from rapamycin-sensitive DLBCL cell lines. Pathway analysis identified Akt as central to the differentially expressed gene network. Connectivity mapping identified compounds targeting Akt as having a high likelihood of reversing the GEP associated with mTOR inhibitor resistance. Nelfinavir and MK-2206, chosen for their Akt-inhibitory properties, yielded synergistic inhibition of cell viability in combination with rapamycin in DLBCL cell lines, and potently inhibited phosphorylation of Akt and downstream targets of activated mTOR. CONCLUSIONS: GEP identifies DLBCL subsets resistant to mTOR inhibitor therapy. Combined targeting of mTOR and Akt suppresses activation of key components of the Akt/mTOR pathway and results in synergistic cytotoxicity. These findings are readily adaptable to clinical trials.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Nelfinavir/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Perfilação da Expressão Gênica , Inibidores da Protease de HIV/farmacologia , Humanos , Técnicas Imunoenzimáticas , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/metabolismo
7.
J Chem Phys ; 135(24): 244507, 2011 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-22225169

RESUMO

Spin-lattice relaxation rates (R(1H) and R(1F)) of two nuclear species ((1)H and (19)F) are measured at different temperatures in the isotropic phase of a liquid crystal (4(')-butoxy-3(')-fluoro-4-isothiocyanatotolane-4OFTOL), over a wide range of Larmor frequency (10 kHz-50 MHz). Their dispersion profiles are found to be qualitatively very different, and the R(1F) in particular shows significant dispersion (varying over two orders of magnitude) in the entire isotropic range, unlike R(1H). The proton spin-lattice relaxation, as has been established, is mediated by time modulation of magnetic dipolar interactions with other protons (case of like spins), and the discernable dispersion in the mid-frequency range, observed as the isotropic to nematic transition is approached on cooling, is indicative of the critical slowing of the time fluctuations of the nematic order. Significant dispersion seen in the R(1F) extending to very low frequencies suggests a distinctly different relaxation path which is exclusively sensitive to the ultra slow modes apparently present in the system. We find that under the conditions of our experiment at low Zeeman fields, spin-rotation coupling of the fluorine with the molecular angular momentum is the dominant mechanism, and the observed dispersion is thus attributed to the presence of slow torques experienced by the molecules, arising clearly from collective modes. Following the arguments advanced to explain similar slow processes inferred from earlier detailed ESR measurements in liquid crystals, we propose that slowly relaxing local structures representing such dynamic processes could be the likely underlying mechanism providing the necessary slow molecular angular momentum correlations to manifest as the observed low frequency dispersion. We also find that the effects of the onset of cross-relaxation between the two nuclear species when their resonance lines start overlapping at very low Larmor frequencies (below ~400 kHz), provide an additional relaxation contribution.

8.
J Phys Chem B ; 113(19): 6994-7002, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19388636

RESUMO

Proton magnetic relaxation dispersion investigations with aqueous solutions of lysozyme and bovine serum albumin (BSA) in the 0-5 M range of guanidine hydrochloride (GdnHCl), pH 4.4, 27 degrees C, were taken up with the objective of examining the hydration dynamics of internal cavity waters as the protein is held under increasingly destabilizing conditions. Field cycling NMR and conventional pulsed NMR techniques were employed to cover a frequency range of 100 kHz to 50 MHz. Analyses of dispersion profiles at different concentrations of GdnHCl were carried out considering the contributions from internal and surface waters. The denaturant-dependent variation of internal water contribution indicates that the reorientational disorder of internal waters decreases with increments of the denaturant up to its subdenaturing limit. For both proteins, the variation of effective correlation time with GdnHCl apparently shows a marginal shrink in hydrodynamic volumes under the subdenaturing condition. These results suggest that subdenaturing amounts of GdnHCl restrict the motional freedom of the internal waters, and can have considerable influence on the surface hydration. On increasing the denaturant concentration further, the dispersion amplitude drops sharply, indicating that the chaotropic action of the denaturant now runs over its own cavity water-ordering effect operative in the subdenaturing limit. The results are fundamentally important for the understanding of the susceptibility of protein structure and hydration to denaturants.


Assuntos
Guanidina/farmacologia , Muramidase/química , Dinâmica não Linear , Soroalbumina Bovina/química , Água/química , Animais , Bovinos , Galinhas , Feminino , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Desnaturação Proteica/efeitos dos fármacos , Temperatura
9.
Arch Microbiol ; 191(2): 171-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18987844

RESUMO

Phytase and endoglucanase enzymes are being widely used as feed additives in poultry industry. In our earlier studies, the Bacillus phytase, when expressed in Escherichia coli, was found in inclusion bodies, whereas endoglucanase was found in active soluble form. Herein, we report the development of a chimeric gene construct coding for ~73 kDa fusion protein and its over-expression in E. coli in soluble form. The novel enzyme exhibited both endoglucanase and phytase activities across broad pH (4.0-8.0) and temperature (25-75 degrees C) ranges. As such, the bi-functional enzyme seems promising and might serve as a potential feed additive for enhanced nutrition uptake in monogastric animals.


Assuntos
6-Fitase/metabolismo , Bacillus/enzimologia , Proteínas de Bactérias/metabolismo , Celulase/metabolismo , Escherichia coli/metabolismo , Engenharia de Proteínas , 6-Fitase/química , 6-Fitase/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Celulase/química , Celulase/genética , Estabilidade Enzimática , Escherichia coli/genética , Expressão Gênica , Corpos de Inclusão/genética , Corpos de Inclusão/metabolismo , Peso Molecular , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
10.
Eur J Surg Oncol ; 30(9): 993-7, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15498647

RESUMO

AIM: The femur is the most common long bone involved in metastatic breast cancer. Several studies have been published on the surgical management of metastatic disease of the femur. However, only few studies have been published specifically on the outcomes following reconstruction of femoral metastasis from breast cancer using a third generation intramedullary nail. The aim of this study is to review the outcomes after intramedullary surgical stabilization of femoral metastases from breast cancer. This is often associated with significant bone destruction. METHODS: A retrospective study of 18 femoral metastatic lesions in 15 patients treated with a Long Gamma Nail over a 6-year period was carried out. Pain relief, mobilization status and implant related complications were the main outcome measures analyzed. RESULTS: Thirteen out of 15 patients had complete pain relief and all patients regained their preoperative mobilization status with or without walking aids. There were no implant failures or perioperative deaths. Four (26%) patients developed minor complications. Ten patients died with an average survival of 9 months and five patients are alive with an average survival of 32 months. CONCLUSION: Stabilization of femoral metastases due to breast cancer with Long Gamma Nail is a safe and effective method with acceptable risks.


Assuntos
Pinos Ortopédicos , Neoplasias da Mama/patologia , Neoplasias Femorais/secundário , Neoplasias Femorais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Dor/etiologia , Dor/prevenção & controle , Complicações Pós-Operatórias , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 69(6 Pt 1): 061709, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15244600

RESUMO

Molecular reorientational motions in undeuterated pentyloxybenzylidine hexylanilene (PBHA or 5O.6) and butyloxybenzylidine octylanilene (BBOA or 4O.8) as studied by the quasielastic neutron scattering (QENS) technique in their different mesophases are reported. Models are built up in stages to account for the experimental elastic incoherent structure factor (EISF). It is found that there exist simultaneous reorientational motions of the chain group and the reorientational motions of the whole molecule around its molecular axis in the smectic- G, smectic- B, and smectic- C phases. In smectic- A and nematic phases, additional body axis fluctuations are found to exist in both 5O.6 and 4O.8 systems. The average amplitude of body axis fluctuations is found to be approximately 15 degrees and 25 degrees, respectively, in the smectic- A and nematic phases of 5O.6, and approximately 14 degrees and 29 degrees, respectively, in 4O.8.

12.
J Hand Surg Br ; 29(1): 15-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14734062

RESUMO

We present a prospective study, with 3-year follow-up, of the role and outcome of fasciectomy plus sequential surgical release of structures of the proximal interphalangeal joint in Dupuytren's contracture of the little finger. Our treatment programme involves fasciectomy for all patients followed by sequential release of the accessory collateral ligament and volar plate as necessary. Of the 19 fingers in the study, eight achieved a full correction by fasciectomy alone, and in these cases there was a fixed flexion deformity of 6 degrees at 3 months and 8 degrees at 3 years. The remaining 11 fingers (initial mean deformity 70 degrees flexion) were left with a fixed flexion deformity of 42 degrees after fasciectomy which reduced to 7 degrees with capsulo-ligamentous release. This increased to 26 degrees at 3 months but then remained relatively stable, increasing only to 29 degrees at 3 years. In our experience sequential proximal interphalangeal joint release has led to consistently good results with few complications in the correction of severe Dupuytren's disease of the little finger.


Assuntos
Contratura de Dupuytren/cirurgia , Ligamentos Articulares/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
13.
Knee ; 9(1): 27-30, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11830378

RESUMO

There are few published results in the literature on patello-femoral arthroplasty. The aim of this study was to help to define the place of patello-femoral arthroplasty in the treatment of isolated patello-femoral arthritis. All patients who underwent patello-femoral arthroplasty using the Lubinus prosthesis for patello-femoral arthritis between 1992 and 1998 in two neighbouring district general hospitals were studied. There were 34 patients who underwent 45 arthroplasties. The modified Hungerford and Kenna scoring system and the Insall and Crosby scoring system were used to clinically evaluate the patients. Serial radiographs were assessed for patellar malalignment, mechanical failure and progressive arthritic change. Twenty-three knees (64%) had a good or excellent result, six (17%) had an unsatisfactory result and seven (19%) were revised to either a total knee arthroplasty (5 knees) or patellofemoral arthroplasty (2 knees). Although the results do not compare favourably with those of total knee replacement for generalised arthritis of the knee; we believe that with careful patient selection coupled with careful surgical technique, patello-femoral arthroplasty can be successfully used to treat isolated patello-femoral osteoarthritis.


Assuntos
Artroplastia do Joelho , Fêmur/cirurgia , Prótese do Joelho , Osteoartrite do Joelho/cirurgia , Patela/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fêmur/diagnóstico por imagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/diagnóstico por imagem , Patela/diagnóstico por imagem , Satisfação do Paciente , Radiografia , Estudos Retrospectivos , Resultado do Tratamento
14.
Injury ; 32(5): 395-400, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11382425

RESUMO

We present a retrospective review of 13 patients with periprosthetic femoral fractures treated with the Dall-Miles cable and plate fixation system between 1995 and 1999. Of these, 12 fractures were in relation to hip arthroplasty and one was proximal to the femoral component of a total knee replacement. Mean age at presentation was 77 years (range 66-87) with the male female ratio of 6:7. All patients were followed up until there was evidence of clinical and radiological union. The average follow-up period was 6.5 months (range 2.5-24). We achieved satisfactory results in ten patients with average time to union of 4.4 months. The results were unsatisfactory in three patients who required further revision procedures due to failure of fixation or non-union. Internal fixation of the fracture with the loose femoral component left in-situ led to failure of union in one patient. Varus mal-alignment of the femoral component to the shaft of more than 6 degrees was associated with unsatisfactory outcome in two patients. The Dall-Miles cable and plate system is a useful method of internal fixation for majority of periprosthetic femoral fractures. This method may not be suitable if the femoral component is loose or if it is in varus angulation of more than 6 degrees to the shaft of the femur.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Placas Ósseas , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas/métodos , Complicações Pós-Operatórias/cirurgia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Fraturas do Fêmur/etiologia , Fêmur/fisiopatologia , Humanos , Masculino , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , Suporte de Carga
15.
Biophys J ; 77(2): 1074-85, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10423451

RESUMO

The orientational order and dynamics of the water molecules in form II crystals of bovine pancreatic trypsin inhibitor (BPTI) are studied by (2)H NMR in the temperature range 6-50 degrees C. From the orientation dependence of the single crystal quadrupole splitting and linewidth, the principal components of the motionally averaged quadrupole interaction tensor and the irreducible linewidth components for the orthorhombic crystal are determined. With the aid of water orientations derived from neutron and x-ray diffraction, it is shown that the NMR data can be accounted for by a small number of highly ordered crystal waters, some of which have residence times in the microsecond range. Most of these specific hydration sites must be located at intermolecular contacts. The surface hydration layer that is also present in dilute solution is likely to be only weakly ordered and would then not contribute significantly to the splitting and linewidth from the protein crystal. To probe water dynamics on shorter time scales, the (2)H longitudinal relaxation dispersion is measured for a polycrystalline BPTI sample. The observed dispersion is dominated by rapidly exchanging deuterons in protein side chains, undergoing restricted rotational motions on a time scale of 10 ns.


Assuntos
Aprotinina/química , Animais , Fenômenos Biofísicos , Biofísica , Bovinos , Cristalização , Deutério , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Proteica , Termodinâmica , Água
16.
J Indian Med Assoc ; 97(9): 357-9, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10638080

RESUMO

One hundred and sixty cases of bronchogenic carcinoma were retrospectively analysed. Male to female ratio was 8.4:1, common age group being 40-60 years. The most common (38%) radiological presentation was mass lesion. The predominant histological cell type was squamous cell carcinoma (67%). Most of the patients presented in an advanced stage of the disease of inoperability. The study underlines the various diagnostic madalities in diagnosing lung cancer and emphasises the need for practising doctors to keep in mind the possibilities of bronchogenic carcinoma in all cases of unresolved pneumonia and mass lesion on chest x-ray especially in high risk patients.


Assuntos
Carcinoma/epidemiologia , Neoplasias Pulmonares/epidemiologia , Adulto , Idoso , Carcinoma/diagnóstico , Feminino , Humanos , Índia/epidemiologia , Neoplasias Pulmonares/diagnóstico , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia
17.
J Am Coll Cardiol ; 32(5): 1358-65, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9809948

RESUMO

OBJECTIVES: This study evaluated the clinical safety and long-term results of rotational atherectomy (RA) followed by low-pressure balloon dilatation (percutaneous transluminal coronary angioplasty [PTCA]) for the treatment of in-stent restenosis (ISR). BACKGROUND: In-stent restenosis is associated with a high incidence of recurrence after interventional treatment. Because ISR is due to neointimal hyperplasia, rotational ablation may be a more effective treatment than PTCA. METHODS: Between November 1995 and November 1996, 100 consecutive patients with first-time ISR were treated by RA. Quantitative coronary angiography and intravascular ultrasound (IVUS) were used to analyze the acute procedural results. The incidence of repeat in-stent restenosis and target vessel revascularization (TVR) at follow-up was determined. RESULTS: Procedural success without any major in-hospital complications was achieved in 100% of cases. Slow flow was observed in 3% and creatine kinase-MB enzyme elevation >3x normal occurred in 2%. The mean burr-to-artery ratio was 0.68+/-0.18 and adjuvant balloon dilatation was performed at 4.2+/-2.1 atm. Minimum luminal diameter increased from 0.86+/-0.28 mm to 1.89< or =0.21 mm after RA and to 2.56+/-0.29 mm after adjunct PTCA. Quantitative IVUS analysis showed that 77% of the luminal gain occurred due to rotational ablation of the restenotic tissue and only 23% occurred after adjunct balloon dilation, and further stent expansion did not contribute to the luminal enlarge. ment. At a mean follow-up of 13+/-5 months, repeat in-stent restenosis occurred in 28% of patients with TVR of 26%. Univariate predictors of repeat restenosis were burr-to-artery ratio <0.6, ISR in <90 days of stenting, ostial lesion, stent for a restenotic lesion and diffuse type ISR. CONCLUSIONS: Rotational atherectomy is a safe and feasible technique for treatment of ISR and is associated with a relatively low recurrent restenosis in comparison to historical controls of balloon angioplasty.


Assuntos
Aterectomia Coronária , Oclusão de Enxerto Vascular/cirurgia , Angioplastia Coronária com Balão/efeitos adversos , Angiografia Coronária , Doença das Coronárias/cirurgia , Feminino , Seguimentos , Oclusão de Enxerto Vascular/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Reoperação , Estudos Retrospectivos , Segurança , Stents/efeitos adversos , Ultrassonografia de Intervenção
18.
J Magn Reson ; 135(1): 1-13, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9799667

RESUMO

Nuclear magnetic relaxation dispersion (NMRD) measurements can provide valuable information about the dynamics and structure of macromolecular solutions and other complex fluids. A large number of 1H NMRD studies of water in concentrated protein solutions and in semisolid biological samples have been reported. The observed dispersion usually extends over a wide frequency range and then cannot be described by a Lorentzian spectral density function. We propose here a model-free approach for analyzing such stretched dispersion profiles. Unlike the traditional empirical fitting procedures, the model-free approach is based on rigorous theory and produces parameters with well-defined physical significance. The model-free approach is validated with the aid of synthetic relaxation data, showing that it is robust and accurate, and is then applied to new water 1H NMRD data from solutions of the protein bovine pancreatic trypsin inhibitor (BPTI). By separating the static and dynamic information content of the relaxation dispersion, the model-free analysis shows that the dramatic salt effect observed in BPTI solutions is due almost entirely to a slowing down of protein rotation with little change of protein structure. An analysis of the same data in terms of the empirical dispersion function used in most 1H NMRD studies leads to a qualitatively different picture. We demonstrate that this widely used dispersion function is unphysical and that its parameters do not have the physical meaning usually ascribed to them.


Assuntos
Aprotinina/química , Espectroscopia de Ressonância Magnética , Modelos Estruturais , Animais , Bovinos , Matemática , Conformação Proteica , Reprodutibilidade dos Testes
19.
J Mol Biol ; 282(4): 847-58, 1998 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-9743631

RESUMO

The present NMR study investigates the residence times of the hydration water molecules associated with uncomplexed trp operator DNA in solution by measuring intermolecular nuclear Overhauser effects (NOE) between water and DNA protons, and the nuclear magnetic relaxation dispersion (NMRD) of the water 2H and 17O resonances. Both methods indicate that the hydration water molecules exchange with bulk water on the sub-nanosecond time scale at 4 degreesC. No evidence was obtained for water molecules bound with longer residence times. In particular, the water molecules at the sites of interfacial hydration in the trp repressor/operator complex do not seem kinetically stabilized in the uncomplexed DNA. Analysis of the crystal structures of two different trp repressor/operator complexes shows very similar structural environments for the water molecules mediating specific contacts between the protein and the DNA, whereas much larger variations are observed for the location of corresponding water molecules detected in the crystal structure of an uncomplexed trp operator DNA duplex. Therefore, it appears unlikely that the hydration characteristics of the uncomplexed DNA target would be a major determinant of trp repressor/operator recognition.


Assuntos
Proteínas de Bactérias , DNA/metabolismo , Regiões Operadoras Genéticas/genética , Triptofano/genética , Água/metabolismo , Sequência de Bases , Sítios de Ligação , Cristalização , DNA/química , DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genes Bacterianos/genética , Ligação de Hidrogênio , Cinética , Modelos Moleculares , Netropsina/metabolismo , Ressonância Magnética Nuclear Biomolecular , Prótons , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Solventes , Água/química
20.
Indian J Chest Dis Allied Sci ; 39(2): 129-32, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9339613

RESUMO

A 31-year-old female, pregnant (I trimester), presented with symptoms and signs of bronchial asthma. Chest roentgenogram and computerized tomography of the chest revealed right mid and lower zone opacity (collapse). Bronchoscopic examination revealed intrabronchial growth in the right middle and lower lobe bronchus. Biopsy and histopathological examination confirmed carcinoid tumour. These symptoms and signs disappeared after laser therapy. The lesion, however, recurred two years later.


Assuntos
Neoplasias Brônquicas/cirurgia , Tumor Carcinoide/cirurgia , Terapia a Laser , Complicações Neoplásicas na Gravidez/cirurgia , Adulto , Biópsia , Neoplasias Brônquicas/patologia , Broncoscopia , Tumor Carcinoide/patologia , Feminino , Humanos , Recidiva Local de Neoplasia/diagnóstico , Gravidez , Primeiro Trimestre da Gravidez
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