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1.
Zhonghua Xue Ye Xue Za Zhi ; 38(4): 307-312, 2017 Apr 14.
Artigo em Chinês | MEDLINE | ID: mdl-28468092

RESUMO

Objective: To assess the efficiency and safety of low-dose decitabine in patients with lower-risk myelodysplastic syndrome (MDS) to couple with the clinical significance of MDS-related gene mutations. Methods: This study was done in 4 institutions in Zhejiang Province. A total of 62 newly diagnosed patients with lower-risk MDS were assigned to two groups of decitabine (12 mg·m(-2)·d(-1) for 5 consecutive days) and best supportive care (BSC) . Their bone marrow samples were subject to examinations of MDS-related 15 gene mutations. The primary endpoints were the proportion of patients who achieved overall response (ORR) after at least two cycles and progression-free survival (PFS) , and their relevances to the gene mutations. Results: Of 62 enrolled patients, and 51 cases were included in the final analysis. 16 of 24 patients (66.7%) in decitabine group achieved ORR versus 8 of 27 (29.6%) in BSC group (χ(2)=6.996, P=0.008) ; PFS prolongation of decitabine versus BSC was statistically significant (not reached vs 13.7 months, P=0.037) . Among 51 patients, at least one gene mutation was identified in 20 patients (39.2%) , including 4 single SF3B1 mutation. PFS in cases with gene mutations (not including single SF3B1 mutation) was significantly shorter than of no gene mutation (9.2 months vs 18.5 months, P=0.008) , but not for ORR (37.5% vs 58.1%, P=0.181) . Among 16 patients with mutated genes, ORR in decitabine and BSC groups were 75% (6/8) and 0 (0/8) , respectively. The most adverse events in decitabine group were grade 3 to 4 neutropenia (45.8%) and grade 3 to 4 infections (33.3%) . Conclusion: This preliminary study showed that low-dose decitabine produced promising results with an acceptable safety in lower-risk MDS patients, especially for those with mutated genes. Further study targeting poor prognostic lower-risk MDS patients should be warranted.


Assuntos
Mutação , Síndromes Mielodisplásicas , Antimetabólitos Antineoplásicos , Azacitidina/análogos & derivados , Decitabina , Intervalo Livre de Doença , Humanos , Prognóstico , Risco , Resultado do Tratamento
2.
Genet Mol Res ; 15(3)2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27706589

RESUMO

Ty3-gypsy long-terminal repeat retroelements are ubiquitously found in many plant genomes. This study reports the occurrence of heterogeneous Ty3-gypsy retroelements in four representative bamboo species: Phyllostachys heterocycla (Carr.) Mitford cv. pubescens, P. heterocycla (Carr.) Mitford cv. heterocycla, Dendrocalamopsis oldhami, and Pleioblastus fortunei. Using degenerate oligonucleotide primers corresponding to the conserved domains of reverse transcriptase (rt) genes of Ty3-gypsy retroelements, 165 distinct sequences were amplified from genomic DNA. The length of the nucleotide sequences varied from 366 to 438 bp. The sequences demonstrated a high heterogeneity, with homology ranging from 52.2 to 99.8%. A phylogenetic tree was constructed, including Arabidopsis thaliana and Oryza sativa. Bamboo Ty3-gypsy sequences formed three distinct retroelement clusters (gypsy I-III). Further analysis indicated that there were not only nearly identical Ty3-gypsy retroelements found in distantly related species, but also highly diverse Ty3-gypsy retroelements observed in closely related species. The results of this study provide genetic and evolutionary information about the bamboo genome that could contribute to further studies of repetitive elements in bamboo as well as in other species.


Assuntos
Evolução Molecular , Retroelementos , Sasa/genética , Transferência Genética Horizontal , Genoma de Planta , Filogenia , Análise de Sequência de DNA , Sequências Repetidas Terminais
3.
Bone Joint J ; 98-B(5): 703-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27143745

RESUMO

AIMS: The purpose of the study was to investigate whether closed intramedullary (IM) nailing with percutaneous cement augmentation is better than conventional closed nailing at relieving pain and suppressing tumours in patients with metastases of the femur and humerus. PATIENTS AND METHODS: A total of 43 patients (27 men, 16 women, mean age 63.7 years, standard deviation (sd) 12.2; 21 to 84) underwent closed IM nailing with cement augmentation for long bone metastases. A further 27 patients, who underwent conventional closed IM nailing, served as controls. Pain was assessed using a visual analogue scale (VAS) score pre-operatively (pre-operative VAS), one week post-operatively (immediate post-operative VAS), and at six weeks post-operatively (follow-up post-operative VAS). Progression of the tumour was evaluated in subgroups of patients using F-18-fludeoxyglucose (F-18-FDG) positron emission tomography (PET)/computed tomography (CT) and/or bone scintigraphy (BS), at a mean of 8.8 and 7.2 months post-operatively, respectively. RESULTS: The mean pain scores of patients who underwent closed nailing with cement augmentation were significantly lower than those of the control patients post-operatively (immediate post-operative VAS: 3.8, sd 0.9 versus 6.0, sd 0.9; follow-up post-operative VAS: 3.3, sd 2.5 versus 6.6, sd 2.2; all p < 0.001). The progression of the metastasis was suppressed in 50% (10/20) of patients who underwent closed nailing with augmentation, but in only 8% (1/13) of those in the control group. CONCLUSION: Percutaneous cement augmentation of closed IM nailing improves the relief of pain and limits the progression of the tumour in patients with metastases to the long bones. TAKE HOME MESSAGE: Percutaneous cement augmentation while performing closed IM nailing has some advantages for long bone metastases. Cite this article: Bone Joint J 2016;98-B:703-9.


Assuntos
Cimentos Ósseos/uso terapêutico , Neoplasias Ósseas/secundário , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas , Fraturas Espontâneas/cirurgia , Fraturas do Úmero/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/cirurgia , Dor do Câncer/etiologia , Dor do Câncer/cirurgia , Estudos de Casos e Controles , Progressão da Doença , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/etiologia , Fraturas Espontâneas/diagnóstico por imagem , Fraturas Espontâneas/etiologia , Humanos , Fraturas do Úmero/diagnóstico por imagem , Fraturas do Úmero/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escala Visual Analógica , Adulto Jovem
4.
Ann Surg Oncol ; 16(9): 2579-86, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19557478

RESUMO

BACKGROUND: Decreased performance status, comorbidities, and disease natural history may erode enthusiasm for soft tissue sarcoma (STS) resection in elderly patients. Consequently, we evaluated the outcome of elderly patients amenable to complete surgical resection treated at a single institution. METHODS: Prospectively accrued data were used to identify patients with primary STS age >or=65 years (n = 325) who underwent complete macroscopic resection at our institution (1996-2007). Univariable and multivariable analyses were performed to identify prognostic factors. RESULTS: Median age at presentation was 72 years; 179 patients (55.1%) had associated comorbidities with an ASA score of >or=3. Extremity was the most common site (57.1%; n = 186), undifferentiated pleomorphic sarcoma the most common histology (60.4%; n = 197); 232 (71.2%) were high grade, 222 (68.3%) were >5 cm. Thirty-day postoperative mortality was 0.9% (n = 3); overall complication rate was 30.7% (n = 100), and mean postoperative hospital stay was 9 days (range, 1-84). Estimated median survival was 96 months, 5-year disease-specific survival (DSS) was 63%. Multivariable analysis identified age >or=75 year (HR = 2.03), tumor size: 5-15 vs <5 cm (HR = 3.54), or >15 vs <5 cm (HR = 10.33), and high-grade (HR = 5.53) as significant independent adverse prognostic factors. Compared with patients aged 65-74 years, older patients had more high grade tumors (P = .04), received chemotherapy less often (P < .0001), developed different patterns of recurrence (P < .05), and exhibited a shorter median survival (70 months; P = .05). CONCLUSIONS: Properly selected elderly patients can safely undergo extensive STS resections. Until more effective therapies become available, surgery in the elderly is indicated and remains the best means for STS control.


Assuntos
Sarcoma/cirurgia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Feminino , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Sarcoma/patologia , Taxa de Sobrevida , Resultado do Tratamento
5.
J Pharm Biomed Anal ; 38(3): 487-96, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15925250

RESUMO

A method for measuring a human immunodeficiency virus (HIV) cell membrane fusion inhibitor (T-20/Ro 29-9800) and its metabolite (M-20/Ro 50-6343) in human plasma by liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed. The relatively large peptide analytes and their corresponding deuterated (d(10)) peptides used as internal standard were isolated from plasma by protein precipitation with two volumes of acetonitrile to plasma. A large pore size reversed-phase C(18) column was employed to elute the peptides. A triple quadrupole mass spectrometer with electrospray interface operating in positive ion and multiple reaction monitoring modes with transitions m/z 1124-->1343 for both T-20 and M-20 was utilized for peak detection. The advantages of the method were a simple sample preparation, specific and sensitive MS/MS detection, and a wide dynamic range of 10-2000 ng/ml for T-20. The method was validated and used for analyzing samples from clinical studies to provide pharmacokinetic profiles of the HIV fusion inhibitor peptide drug and its metabolite.


Assuntos
Cromatografia Líquida/métodos , Proteína gp41 do Envelope de HIV/sangue , Inibidores da Fusão de HIV/sangue , Espectrometria de Massas/métodos , Fragmentos de Peptídeos/sangue , Adsorção , Sequência de Aminoácidos , Calibragem , Estabilidade de Medicamentos , Drogas em Investigação/análise , Drogas em Investigação/química , Drogas em Investigação/uso terapêutico , Enfuvirtida , Inibidores da Fusão de HIV/química , Inibidores da Fusão de HIV/farmacocinética , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/farmacocinética , Fragmentos de Peptídeos/normas , Padrões de Referência , Reprodutibilidade dos Testes , Tecnologia Farmacêutica/métodos
6.
Environ Mol Mutagen ; 37(4): 304-10, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11424180

RESUMO

Lung cancer is the leading cause of cancer mortality in Taiwanese women. Cigarette smoking cannot explain the high lung cancer mortality in this population because less than 10% of women in Taiwan are smokers. Therefore, environmental factors other than smoking may play an important role in lung cancer development in female nonsmokers. The purpose of this study was to elucidate the role of environmental carcinogen exposure in lung cancer development in Taiwanese female nonsmokers, based on DNA adduct formation. We collected nontumorous lung tissues resected from 62 nonsmoking lung cancer patients and 20 noncancer controls to investigate whether differences in susceptibility to DNA adduct formation exist between men and women. (32)P-postlabeling and ELISA (enzyme-linked immunosorbent assay) with polyclonal antibody against BPDE (7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene)-DNA adduct were used to evaluate DNA adduct levels in lung tissues of study subjects. Our data showed that the DNA adduct levels of lung cancer patients determined by both assays were significantly higher than those of noncancer controls (P = 0.0001 for (32)P-postlabeling; P = 0.01 for ELISA). Moreover, DNA adduct levels in females were markedly greater than those in males (P = 0.014 for (32)P-postlabeling; P = 0.001 for ELISA). The difference in DNA adduct levels could not be explained by genetic polymorphisms of cytochrome P-4501A1 (CYP1A1) or glutathione S-transferase (GSTM1), as determined by polymerase chain reaction and restriction fragment length polymorphism. These results demonstrate that lung cancer patients have a higher susceptibility to DNA damage than that of noncancer controls. In addition, differences in susceptibility to DNA damage derived from environmental carcinogen exposure were observed between male and female nonsmokers. In conclusion, high susceptibility to DNA damage in females may partially explain the high mortality rate of lung cancer in nonsmoking Taiwanese women.


Assuntos
Adutos de DNA , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Fumar , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/metabolismo , Animais , Citocromo P-450 CYP1A1/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Glutationa Transferase/genética , Humanos , Masculino , Polimorfismo Genético , Coelhos , Fatores Sexuais
7.
Cancer Res ; 59(7): 1428-32, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10197607

RESUMO

The t(11;22)(q24;q12) translocation is present in up to 95% of cases of Ewing's sarcoma and results in the formation of an EWS-FLI1 fusion gene which encodes a chimeric transcription factor. The proximate role of EWS-FLI1 in the pathogenesis of Ewing's sarcoma is thought to involve the activation of as yet largely unknown target genes. Many alternative forms of EWS-FLI1 exist because of variations in the locations of the EWS and FLI1 genomic breakpoints. The most common form, designated "type 1," consists of the first seven exons of EWS joined to exons 6-9 of FLI1 and accounts for approximately 60% of cases. The "type 2" EWS-FLI1 fusion also includes FLI1 exon 5 and is present in another 25%. We and others have observed previously that the type 1 fusion is associated with a significantly better prognosis than the other fusion types. Because EWS-FLI1 is an aberrant transcription factor, we investigated whether these differences in clinical behavior may be correlated to functional differences by comparing transactivation by the type 1 EWS-FLI1 with other types in both heterologous cells (HeLa, NIH3T3) and homologous cells (Ewing's sarcoma cell lines). In a panel of seven Ewing's sarcoma cell lines, we found transactivation of a transiently transfected FLI1-responsive reporter construct to be significantly lower in cell lines with the type 1 fusion than in cell lines with the type 2 fusion (P = 0.003). Cotransfection of the same reporter construct with each of a series of seven EWS-FLI1 expression constructs (corresponding to the two major fusion types and five less common types) also showed that type 1 EWS-FLI1 was a significantly weaker transactivator than the type 2 product in both HeLa and NIH3T3 cells (P = 0.003, and P = 0.033, respectively). Electromobility shift assays showed equivalent binding of the type 1 and type 2 EWS-FLI1 to the consensus FLI1-responsive binding site, indicating that differences in transactivation were not due simply to differences in DNA binding affinity. The finding that the type 1 EWS-FLI1 fusion, associated with less aggressive clinical behavior, encodes a less active chimeric transcription factor may provide the basis for a molecular explanation of clinical heterogeneity in Ewing's sarcoma.


Assuntos
Proteínas de Fusão Oncogênica/fisiologia , Proteínas Proto-Oncogênicas , Sarcoma de Ewing/genética , Fatores de Transcrição/fisiologia , Ativação Transcricional , Células 3T3 , Animais , Proteínas de Ligação a DNA/genética , Éxons , Células HeLa , Humanos , Camundongos , Proteína Proto-Oncogênica c-fli-1 , Proteína EWS de Ligação a RNA , Transativadores/genética
8.
J Surg Oncol ; 70(2): 109-15, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10084654

RESUMO

BACKGROUND AND OBJECTIVES: Limb-sparing surgery has become the preferred surgical treatment of malignant bone tumors. The objective of this study was to evaluate factors that influence the morbidity and outcome of prosthetic knee replacement after resection of malignant tumors of the distal femur. METHODS: Eighty-two patients who had a resection of malignant tumor of the distal femur and implantation of a segmental knee prosthesis (minimum follow-up, 2 years) were retrospectively reviewed. RESULTS: Twenty-nine patients (35%) underwent 32 prosthetic revisions, 6 from perioperative wound complications, 13 from aseptic loosening, and 13 from other complications. The 3-, 5-, and 10-year Kaplan-Meier prosthetic survival rates were 82%, 71%, and 50%, respectively. On univariate analysis, patients who had more than 40% resection of the distal femur (P = 0.010) and those who had all their vasti muscles resected (P = 0.011) had significantly worse prosthetic survivals than the others. On multivariate analysis, resection of more than 40% of the distal femur was a significant negative prognostic factor for prosthetic survival (P = 0.017). Aseptic loosening was the primary cause of late prosthetic failure. Differences in the magnitude of resection influenced prosthetic survivorship more than prosthetic design. CONCLUSIONS: In the distal femoral endoprosthetic replacement, higher short- and long-term complications were found after extensive resections. Aseptic loosening was the primary cause of prosthetic failure.


Assuntos
Artroplastia do Joelho/efeitos adversos , Neoplasias Femorais/cirurgia , Prótese do Joelho , Procedimentos de Cirurgia Plástica , Falha de Prótese , Adolescente , Adulto , Artroplastia do Joelho/mortalidade , Criança , Condrossarcoma/mortalidade , Condrossarcoma/cirurgia , Feminino , Neoplasias Femorais/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Osteossarcoma/mortalidade , Osteossarcoma/cirurgia , Complicações Pós-Operatórias/epidemiologia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Taxa de Sobrevida
9.
J Chromatogr B Biomed Sci Appl ; 735(2): 255-69, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10670739

RESUMO

Morphine (MOR) is an opioid analgesic used for the treatment of moderate to severe pain. MOR is extensively metabolized to morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). A rapid and sensitive method that was able to reliably detect at least 0.5 ng/ml of MOR and 1.0 ng/ml of M6G was required to define their pharmacokinetic profiles. An LC-MS-MS method was developed in our laboratory to quantify all three analytes with the required sensitivity and a rapid turnaround time. A solid-phase extraction (SPE) was used to isolate MOR, M3G, M6G, and their corresponding deuterated internal standards from heparinized plasma. The extract was injected on a LC tandem mass spectrometer with a turbo ion-spray interface. Baseline chromatographic separation among MOR, M3G, and M6G peaks was achieved on a silica column with an aqueous organic mobile phase consisting of formic acid, water, and acetonitrile. The total chromatographic run time was 3 min per injection, with retention times of 1.5, 1.9 and 2.4 min for MOR, M6G, and M3G, respectively. Chromatographic separation of M3G and M6G from MOR was paramount in establishing the LC-MS-MS method selectivity because of fragmentation of M3G and M6G to MOR at the LC-MS interface. The standard curve range in plasma was 0.5-50 ng/ml for MOR, 1.0-100 ng/ml for M6G, and 10-1000 ng/ml for M3G. The inter-day precision and accuracy of the quality control (QC) samples were <7% relative standard deviation (RSD) and <6% relative error (R.E.) for MOR, <9% RSD and <5% R.E. for M6G, and <3% RSD and <6% R.E. for M3G. Analyte stability during sample processing and storage were established. Method ruggedness was demonstrated by the reproducible performance from multiple analysts using several LC-MS-MS systems to analyze over one thousand samples from clinical trials.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Derivados da Morfina/sangue , Morfina/sangue , Cromatografia Líquida/instrumentação , Humanos , Compostos Orgânicos , Reprodutibilidade dos Testes , Dióxido de Silício , Solventes
10.
Appl Opt ; 38(9): 1767-71, 1999 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-18305803

RESUMO

A prototype solid-state, multispectral hybrid laser has been designed and tested. The laser provides simultaneous outputs at several wavelengths. The hybrid-laser concept is based on the efficient use of flash-lamp-pump energy distributed between two complementary lasing materials, Nd:YAG and Cr:LiSAF, that share the same pump cavity. The prototype Q-switched hybrid laser provides dual-fundamental-wavelength output at 850 and 1064 nm as well as frequency-doubled output at 532 nm. The laser achieved 3.6% slope efficiency (combined) in free-running operation and 2.4% when Q switched. Higher efficiencies can be obtained with improvements in laser crystal quality and pump cavity configuration.

11.
Iowa Orthop J ; 18: 12-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9807703

RESUMO

To determine if expression of specific proteoglycan epitopes distinguishes articular cartilage repair tissue from normal articular cartilage, we used seven monoclonal antibodies to examine normal articular cartilage and cartilage repair tissue from osteochondral defects 3.2 mm in diameter and 4.0 mm deep in the medial femoral condyles of 27 New Zealand white rabbits and seven cynomolgus monkeys. Following creation of the osteochondral defects, one limb of each animal was treated with cast immobilization while the other limb was treated with passive motion for two weeks. Rabbit knees were examined at eight (13 animals, 26 knees) and 36 weeks (14 animals, 28 knees) and monkey knees at eight weeks (seven animals, 14 knees) following surgery. Staining for six of the antibodies did not differ between repair cartilage and normal articular cartilage, but an antibody that recognizes atypical glycosaminoglycan structures in developing tissues (MAb 7D4) consistently distinguished repair cartilage from normal cartilage in rabbits and monkeys. Repair tissue consisting of hyaline toluidine blue-staining matrix containing chondrocytic cells uniformly showed strong 7D4 staining. In contrast, normal articular cartilage and fibrous repair tissue showed inconsistent weak 7D4 staining. At eight weeks following surgery, rabbit cartilage repair tissue stained more intensely for 7D4 than monkey cartilage repair tissue; in rabbits, cartilage repair tissue stained more intensely for 7D4 at eight weeks than at 36 weeks following surgery. Repair tissue staining for 7D4 did not differ between osteochondral defects treated with passive motion and those treated with immobilization in rabbits and monkeys. These results indicate that expression of a high level of proteoglycan epitope 7D4 distinguishes hyaline articular cartilage repair tissue from normal articular cartilage and fibrous cartilage repair tissue in the early stages of osteochondral healing, and that as hyaline articular cartilage repair tissue matures expression of 7D4 decreases. The ability to characterize repair cartilage proteoglycans with monoclonal antibodies may aid in the evaluation of the quality and maturity of cartilage repair tissue and thereby facilitate improvements in procedures for resurfacing joints.


Assuntos
Cartilagem Articular/metabolismo , Proteoglicanas/metabolismo , Cicatrização/fisiologia , Animais , Anticorpos Monoclonais , Cartilagem Articular/lesões , Epitopos , Fêmur , Imuno-Histoquímica , Macaca fascicularis , Terapia Passiva Contínua de Movimento , Coelhos , Estatísticas não Paramétricas
12.
Protein Sci ; 7(6): 1451-7, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9655350

RESUMO

Posttranslational modification of protein lysyl residues that change the net charge of the molecule may alter the protein conformation. Such modifications are of particular significance among lens proteins, because conformational changes are associated with the development of cataract. A previously unidentified acetylated form of alphaA-crystallin has been isolated from the water-soluble portion of human lenses. The alphaA-crystallins were fractionated by anion exchange HPLC into seven peaks, each containing more than one form of alphaA-crystallin. The previously reported deamidated and phosphorylated forms were identified by their molecular masses, determined by electrospray ionization mass spectrometry. In addition to these modifications, approximately 5% of alphaA-crystallin had a modification that decreased the charge by one and increased the molecular mass by 42 u. This modification, identified as acetylation, was located uniquely at Lys 70. Like any modification that alters the surface charge, acetylation may affect protein conformation and intermolecular interactions, thereby altering the solubility or chaperone properties of alphaA-crystallin. Acetylation of lysine 70 is potentially significant since it is located in a region that has been implicated in the chaperone activity of alphaA-crystallin.


Assuntos
Cristalinas/química , Cristalino/química , Lisina/química , Acetilação , Sequência de Aminoácidos , Fracionamento Químico , Cromatografia Líquida de Alta Pressão , Cristalinas/isolamento & purificação , Humanos , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Tripsina/metabolismo
13.
Cancer ; 82(12): 2356-65, 1998 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9635528

RESUMO

BACKGROUND: Surgical resection and adjuvant radiation therapy are standard therapy for soft tissue sarcomas. When the tumor approximates bone, periosteal excision may be necessary. It was hypothesized that periosteal stripping and radiation therapy would increase the rate of pathologic fracture. METHODS: The soft tissue sarcoma data base at the Memorial Sloan-Kettering Cancer Center was used to identify a consecutive series of 205 patients who were treated over a 15-year period (1982-1997). All patients had a soft tissue sarcoma of the thigh, which was managed by limb-sparing surgery and radiation therapy. Patients who had bone invasion by tumor or bone resection were not included. RESULTS: Nine patients, including eight women and one man, developed a femoral fracture in an area of previous radiation and surgery. All nine patients had undergone periosteal excision. The risk of fracture, by Kaplan-Meier survivorship, was 29% at 5 years if the resection included periosteum (P < 0.0001). Cox multiple regression analysis showed that periosteal excision was the only independent prognostic factor for the entire set of 205 patients at risk. However, for the subset of 54 patients who had periosteal stripping, two factors were also found to be prognostically important: female gender (P=0.022) and chemotherapy (P=0.020). The risk of fracture was 47% and 45%, respectively. The treatment of the fractures was difficult. There were four nonunions and three delayed unions. CONCLUSIONS: Periosteal stripping and radiation therapy places the femur at high risk of pathologic fractures, especially for female patients and patients undergoing chemotherapy. When practical, the combination of periosteal stripping and radiation should be avoided.


Assuntos
Fraturas do Fêmur/etiologia , Fraturas Espontâneas/etiologia , Periósteo/cirurgia , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Sarcoma/patologia , Sarcoma/radioterapia , Fatores Sexuais , Neoplasias de Tecidos Moles/patologia , Neoplasias de Tecidos Moles/radioterapia
14.
Clin Orthop Relat Res ; (352): 168-78, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9678045

RESUMO

Twelve fractures of the femur occurred after irradiation in 12 patients during the past 15 years. All 12 patients had excision of a soft tissue sarcoma of the thigh. The periosteum was stripped in every case. The fractures had a deceptively innocuous radiographic appearance, which showed minimal comminution, displacement, and shortening. Treatment of the fractures was difficult and demanding. At a mean followup of 37 months, bony union was achieved in only four patients, and in all four cases union was delayed beyond 12 months. Because fracture healing typically is delayed, a loadsharing device such as an intramedullary nail may be preferable in treating these fractures. Primary or delayed bone grafting may be necessary, for no fracture united without bone graft. For elderly patients with low supracondylar fractures, primary endoprosthetic replacement may effect quicker rehabilitation. The possibility of local recurrence of tumor should be ruled out before definitive surgical treatment of the fracture. Closed, antegrade nailing in the presence of recurrent tumor may contaminate the flap for a salvage procedure such as hemipelvectomy and may compromise chances for cure.


Assuntos
Fraturas do Fêmur/cirurgia , Fraturas Espontâneas/cirurgia , Osteorradionecrose/complicações , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/radioterapia , Transplante Ósseo , Terapia Combinada , Feminino , Fraturas do Fêmur/etiologia , Seguimentos , Fixação Intramedular de Fraturas , Consolidação da Fratura , Fraturas Espontâneas/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Coxa da Perna , Fatores de Tempo
15.
Clin Orthop Relat Res ; (352): 194-201, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9678048

RESUMO

Current methods of treating calcaneus fractures vary greatly, and many techniques of internal fixation have been described. The study of these fractures has been limited in part by the lack of a suitable laboratory model. In this study, a new cadaveric model of calcaneus fractures was developed, using a combination of osteotomies and impaction. The model allows a pattern of intraarticular injury to be reproduced consistently. The model was used to examine one aspect of internal fixation. It was hypothesized that fixation would be more stable if the screws supporting the posterior facet were incorporated into the lateral plate, as opposed to being separate from the plate. Six pairs of anatomic specimen legs were used, and each pair was divided randomly between two experimental groups. In Group A (screws out), the posterior facet screws were outside the plate, and in Group B (screws in), the screws were incorporated into the plate. The strength of the reconstructed calcanei were evaluated by axial loading of the limb through the tibia. Stiffness and energy to failure were significantly greater and Bohler's angle significantly less compromised in Group B. It was concluded that the position of the articular fragment of comminuted calcaneal fractures will be maintained at higher loads when the screws in the posterior facet are incorporated into the lateral plate. The model of calcaneal fractures described in this study may be suitable for examining other aspects of fixation.


Assuntos
Parafusos Ósseos , Calcâneo/lesões , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Placas Ósseas , Cadáver , Humanos , Osteotomia , Estresse Mecânico
16.
J Surg Oncol ; 68(1): 41-7, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9610662

RESUMO

BACKGROUND AND OBJECTIVES: Patients with cancer and patients undergoing major orthopedic procedures are two groups at risk of deep venous thrombosis (DVT). The objective was to determine the rate of venous thromboembolic disease in patients with a malignant neoplasm and major orthopaedic surgery of the lower limb. METHODS: The study included 169 patients. All patients were given knee-high intermittent pneumatic compression devices for prophylaxis. Postoperative surveillance for thrombosis was performed on all patients with venous duplex doppler ultrasonography. RESULTS: Proximal DVT occurred in 24 of 169 patients (14.2%). One patient (0.6%) developed a symptomatic, nonfatal pulmonary embolus (PE). The development of DVT was not associated with age, sex, type of surgery, type of neoplasm, location, or pathologic fracture. The addition of anticoagulant medication such as warfarin did not significantly reduce the rate of DVT in a subset of 54 patients. In three patients, the DVT occurred only in the contralateral limb, and in four patients, there were bilateral DVTs. CONCLUSIONS: When intermittent compression boots were used for prophylaxis in conjunction with ultrasound screening, the risk of proximal DVT was substantial (14.2%), but the rate of symptomatic PE was low (0.6%).


Assuntos
Perna (Membro)/cirurgia , Neoplasias/complicações , Procedimentos Ortopédicos , Complicações Pós-Operatórias , Tromboflebite/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril , Artroplastia do Joelho , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/métodos , Pelve/cirurgia , Estudos Prospectivos , Tromboflebite/epidemiologia , Tromboflebite/prevenção & controle
17.
Cancer ; 82(5): 851-9, 1998 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9486573

RESUMO

BACKGROUND: Treatment of malignant tumors of the pelvis represents one of the most difficult problems in musculoskeletal oncology. However, factors that influence the local and systemic control of the disease remain ill-defined. METHODS: One hundred and two patients with localized pelvic sarcomas who underwent a surgical excision of the tumors were analyzed. The tumor diagnosis was chondrosarcoma in 49 patients, osteosarcoma in 26 patients, Ewing's sarcoma in 20 patients, and other tumors in 7 patients. The tumor was located in the ilium in 65 patients, the pubis in 21 patients, the ischium in 8 patients, and the sacrum in 8 patients. Eighty-three patients underwent a limb-sparing surgery and 19 patients underwent hemipelvectomy. Prognostic factors for local recurrence, metastasis, and survival were analyzed. RESULTS: At last follow-up, 47 patients were disease free, 7 were alive with disease, and 48 had died. The 5-year survival rate was 55% (chondrosarcoma: 65%, osteosarcoma: 47%, and Ewing's sarcoma: 52%). Inadequate surgical margin emerged as the only independent adverse prognostic factor for local recurrence. For distant metastasis, surgical stage remained as an independent prognostic factor. Patients who underwent a hemipelvectomy and those who had an inadequate surgical margin had significantly poorer survivals. CONCLUSIONS: Pelvic sarcomas remain diseases with a poor prognosis. Independent prognostic factors are few; an adequate surgical margin is critical to prevent local recurrence, and the surgical stage is related to the risk of distant metastasis. Surgical margins and hemipelvectomy were predictors of survival, but the patients who underwent hemipelvectomy also tended to have the largest, most advanced tumors. Hemipelvectomy should be considered when there is sacral involvement.


Assuntos
Neoplasias Ósseas/cirurgia , Ossos Pélvicos , Sarcoma/cirurgia , Adolescente , Adulto , Idoso , Neoplasias Ósseas/patologia , Criança , Condrossarcoma/secundário , Condrossarcoma/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Osteossarcoma/secundário , Osteossarcoma/cirurgia , Prognóstico , Fatores de Risco , Sarcoma/secundário , Sarcoma de Ewing/secundário , Sarcoma de Ewing/cirurgia , Análise de Sobrevida
19.
Dev Med Child Neurol ; 38(9): 782-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8810709

RESUMO

To assess the impact of neurologic involvement on bone mineralization, dual-energy X-ray absorptiometry was used to quantitate bone mineral content (BMC), bone mineral density (BMD), fat and lean muscle mass in the limbs of 19 children with spastic hemiplegic cerebral palsy. The BMC in the affected limb was on average 26.5% lower (upper limbs) and 15.6% lower (lower limbs) than in the corresponding uninvolved limb. Lean muscle mass was reduced by 15% and BMD by 6% in the involved limbs and did not differ significantly between upper and lower limbs. The fat content of involved and uninvolved limbs did not differ. Children with poor hand function had greater reductions in BMC (39.3%), BMD (11.3%) and lean muscle mass (22.5%) than did children with better hand function. Thus, bone size and density decrease with increasing neurologic involvement, and weight bearing may slightly lessen the effect.


Assuntos
Calcificação Fisiológica , Hemiplegia/complicações , Espasticidade Muscular/complicações , Adolescente , Reabsorção Óssea , Criança , Pré-Escolar , Estudos Transversais , Processamento Eletrônico de Dados , Extremidades/fisiopatologia , Hemiplegia/fisiopatologia , Humanos , Espasticidade Muscular/fisiopatologia
20.
Toxicol Lett ; 84(1): 23-32, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8597174

RESUMO

Epidermal basal keratinocytes are the primary target in BCES-induced cutaneous injury. DNA synthesis is inhibited by exposure to BCES which could relate to the mustard's cytotoxic effect. The effects of BCES on the cell cycle in keratinocytes synchronized by aphidicolin were investigated. Primary keratinocytes synchronized at the G1/S boundary entered the S, G2, M, and G1 phases at successive times after release from the block. When cells were exposed to 1, 10, or 50 microM BCES in different phases of the cell cycle, cells in the S phase were more sensitive to BCES than cells in the other phases. Keratinocytes exposed to 1 microM BCES at the G1/S boundary exhibited a prolongation of the S phase and a block in the G2 phase. When these cells were exposed to 10 or 50 microM BCES, they did not enter the S phase for up to 12h and the incorporation of thymidine into DNA was inhibited. These results suggest that the blocks in the G2 and G1 phases relate to the cytotoxic effect of BCES on the germinative population of epidermal keratinocytes.


Assuntos
Ciclo Celular/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Gás de Mostarda/toxicidade , Animais , Animais Recém-Nascidos , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , DNA/biossíntese , Feminino , Fase G1/efeitos dos fármacos , Fase G2/efeitos dos fármacos , Queratinócitos/citologia , Ratos , Fase S/efeitos dos fármacos
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