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1.
Cartilage ; : 19476035231226218, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38282570

RESUMO

OBJECTIVE: Supply-demand mismatch of medial femoral condyle (MFC) osteochondral allografts (OCAs) remains a rate-limiting factor in the treatment of osteochondral defects of the femoral condyle. Surface contour mapping was used to determine whether a contralateral lateral femoral condyle (LFC) versus ipsilateral MFC OCA differs in the alignment of donor:native subchondral bone for large osteochondral defects of the MFC. DESIGN: Thirty fresh-frozen human femoral condyles were matched by tibial width into 10 groups of 3 condyles (MFC recipient, MFC donor, and LFC donor) each for 3 cartilage surgeons (90 condyles). The recipient MFC was imaged using nano-computed tomography scan. Donor oval grafts were harvested from each matched condyle and transplanted into a 17 mm × 36 mm defect created in the recipient condyle. Following the first transplant, the recipient condyle was imaged and superimposed on the native condyle nano-CT scan. The donor plug was removed and the process repeated for the other donor. Surface height deviation and circumferential step-off height deviation were compared between native and donor subchondral bone surfaces for each transplant. RESULTS: There was no statistically significant difference in mean subchondral bone surface deviation (LFC = 0.87 mm, MFC = 0.76 mm, P = 0.07) nor circumferential step-off height (LFC = 0.93 mm, MFC = 0.85 mm, P = 0.09) between the LFC and MFC plugs. There were no significant differences in outcomes between surgeons. CONCLUSIONS: There were no significant differences in subchondral bone circumferential step-off or surface deviation between ipsilateral MFC and contralateral LFC oval-shaped OCAs for 17 mm × 36 mm defects of the MFC.

2.
Front Oncol ; 13: 1225646, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37927472

RESUMO

Introduction: Next-generation sequencing (NGS) is currently widely used for biomarker studies and molecular profiling to identify concurrent alterations that can lead to the better characterization of a tumor's molecular landscape. However, further evaluation of technical aspects related to the detection of gene rearrangements and copy number alterations is warranted. Methods: There were 12 ALK rearrangement-positive tumor specimens from patients with non-small cell lung cancer (NSCLC) previously detected via fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and an RNA-based NGS assay, and 26 MET high gene copy number (GCN) cases detected by FISH, selected for this retrospective study. All 38 pre-characterized cases were reassessed utilizing the PGDx™ elio™ tissue complete assay, a 505 gene targeted NGS panel, to evaluate concordance with these conventional diagnostic techniques. Results: The detection of ALK rearrangements using the DNA-based NGS assay demonstrated excellent sensitivity with the added benefit of characterizing gene fusion partners and genomic breakpoints. MET copy number alterations were also detected; however, some discordances were observed likely attributed to differences in algorithm, reporting thresholds and gene copy number state. TMB was also assessed by the assay and correlated to the presence of NSCLC driver alterations and was found to be significantly lower in cases with NGS-confirmed canonical driver mutations compared with those without (p=0.0019). Discussion: Overall, this study validates NGS as an accurate approach for detecting structural variants while also highlighting the need for further optimization to enable harmonization across methodologies for amplifications.

3.
Nat Commun ; 13(1): 2830, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35595835

RESUMO

The lack of validated, distributed comprehensive genomic profiling assays for patients with cancer inhibits access to precision oncology treatment. To address this, we describe elio tissue complete, which has been FDA-cleared for examination of 505 cancer-related genes. Independent analyses of clinically and biologically relevant sequence changes across 170 clinical tumor samples using MSK-IMPACT, FoundationOne, and PCR-based methods reveals a positive percent agreement of >97%. We observe high concordance with whole-exome sequencing for evaluation of tumor mutational burden for 307 solid tumors (Pearson r = 0.95) and comparison of the elio tissue complete microsatellite instability detection approach with an independent PCR assay for 223 samples displays a positive percent agreement of 99%. Finally, evaluation of amplifications and translocations against DNA- and RNA-based approaches exhibits >98% negative percent agreement and positive percent agreement of 86% and 82%, respectively. These methods provide an approach for pan-solid tumor comprehensive genomic profiling with high analytical performance.


Assuntos
Neoplasias , Biomarcadores Tumorais/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação , Neoplasias/patologia , Medicina de Precisão
5.
Mutat Res ; 485(4): 309-18, 2001 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-11585363

RESUMO

Phenolic phytochemicals are natural plant substances whose cellular effects have not been completely determined. Nordihydroguaiaretic acid (NDGA) and curcumin are two phenolic phytochemicals with similar molecular structures, suggesting that they possess comparable chemical properties particularly in terms of antioxidant activity. To examine this possibility in a cellular system, this study evaluated the capacities of NDGA and curcumin to function as antioxidants in inhibiting oxidative damage to DNA. Jurkat T-lymphocytes were pre-incubated for 30 min with 0-25 microM of either NDGA or curcumin to allow for uptake. The phenolic phytochemical-treated cells were then oxidatively challenged with 25 microM hydrogen peroxide (H2O2). Afterwards, cells were subjected to alkaline micro-gel electrophoresis (i.e. comet assay) to assess the extent of single-strand breaks in DNA. In a concentration-dependent manner, NDGA inhibited H2O2-induced DNA damage, whereas curcumin did not. In fact, incubating Jurkat T-lymphocytes with curcumin alone actually induced DNA damage. This effect of curcumin on DNA did not appear to reflect the DNA fragmentation associated with apoptosis because there was no proteolytic cleavage of poly-(ADP-ribose)-polymerase, which is considered an early marker of apoptosis. Curcumin-induced damage to DNA was prevented by pre-treatment of the cells with the lipophilic antioxidant, alpha-tocopherol, suggesting that curcumin damaged DNA through oxygen radicals. Therefore, it is concluded that NDGA has antioxidant activity but curcumin has prooxidant activity in cultured cells based on their opposite effects on DNA.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Fenóis/farmacologia , Plantas/química , Ensaio Cometa , Curcumina/farmacologia , Humanos , Células Jurkat , Masoprocol/farmacologia , Estresse Oxidativo
6.
J Cell Biochem ; 81(4): 647-58, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11329619

RESUMO

Ingesting phenolic phytochemicals in many plant products may promote health, but the effects of phenolic phytochemicals at the cellular level have not been fully examined. Thus, it was determined if the tea phenolic phytochemical, epigallocatechin gallate (EGCG), protects U937 human pro-monocytic cells against the nitrogen free radical, nitric oxide (*NO). Cells were incubated for 4-6 h with 500 microM S-nitrosoglutathione (GSNO), which generates *NO, but this did not induce single-strand breaks in DNA. Nevertheless, 82 +/- 4% of GSNO-treated cells, compared to only 39 +/- 1% of untreated cells, were arrested in the G(1)-phase of the cell cycle. However, dosing the GSNO-treated cells with 9, 14, or 18 microg/ml of EGCG resulted in only 74 +/- 8%, 66 +/- 1%, and 43 +/- 3% of the cells, respectively, in the G(1)-phase. Exposing cells to GSNO also resulted in the emergence of a sub-G(1) apoptotic cell population numbering 14 +/- 3%, but only 5 +/- 2%, 5 +/- 1%, and 2 +/- 0% upon dosing of the GSNO-treated cells with 9, 14, and 18 microg/ml of EGCG, respectively. Furthermore, exposing cells to GSNO resulted in greater cell surface binding of annexin V-FITC, but binding was 41-89% lower in GSNO-treated cells dosed with EGCG. Collectively, these data suggest that *NO or downstream products induced cell cycle arrest and apoptosis that was not due to single-strand breaks in DNA, and that EGCG scavenged cytotoxic *NO or downstream products, thus reducing the number of cells in a state of cell cycle arrest or apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Catequina/farmacologia , DNA/efeitos dos fármacos , Sequestradores de Radicais Livres/metabolismo , Fase G2/efeitos dos fármacos , Mitose/efeitos dos fármacos , Óxido Nítrico/metabolismo , Apoptose/fisiologia , Biomarcadores , Catequina/análogos & derivados , Catequina/química , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/fisiologia , DNA/metabolismo , Fragmentação do DNA/fisiologia , Sequestradores de Radicais Livres/química , Humanos , Óxido Nítrico/química , Espécies Reativas de Oxigênio/metabolismo , Células U937
7.
J Pineal Res ; 22(4): 203-9, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9247205

RESUMO

An important property of melatonin is that it is a free-radical scavenger or antioxidant. Since free radicals can induce oxidative modification of low-density lipoprotein (LDL), a process believed to be involved in atherogenesis, we were prompted to evaluate the capacity of melatonin to prevent oxidative modification of LDL. To induce oxidation, human LDL (0.4 mg protein/ml) was incubated at 37 degrees C with either 10 microM cupric chloride or 10 mM 2,2'-azo-bis-(2-amidinopropane) dihydrochloride (AAPH) for 3 hr or 24 hr, respectively. Several assays were then performed to unequivocally determine the extent of LDL oxidation. Compared to native LDL, oxidized LDL had increased agarose gel electrophoretic mobility and weaker immunoreactivity with a murine monoclonal antibody to human apolipoprotein B-100. Measurement of thiobarbituric acid-reactive substances (TBARS) revealed that native LDL contained 1.8 +/- 0.6 nmoles TBARS/mg protein, whereas copper-oxidized LDL contained 53 +/- 4 nmoles TBARS/mg protein. However, when present during incubation, melatonin (0.125-4 mM) inhibited in a concentration-dependent manner the increase in electrophoretic mobility, decrease in immunoreactivity of LDL, and increase in formation of TBARS caused by either copper or AAPH. In a fourth assay, phospholipid analysis of LDL was performed. Native LDL contained 420 +/- 9 nmoles phosphatidylcholine (PC)/mg LDL protein and 30 +/- 20 nmoles lysophosphatidylcholine (LysPC)/mg LDL protein. LDL incubated with copper had a decreased PC content (276 +/- 48 nmoles PC/mg LDL protein) and increased LysPC content (76 +/- 22 nmoles LysPC/mg LDL protein). But when present during the incubation of LDL with copper, melatonin attenuated in a concentration-dependent manner the degradation of PC to LysPC. Therefore, we conclude that melatonin can inhibit oxidative modification of LDL in vitro.


Assuntos
Lipoproteínas LDL/metabolismo , Melatonina/farmacologia , Amidinas/farmacologia , Antioxidantes , Apolipoproteína B-100 , Apolipoproteínas B/metabolismo , Cobre/farmacologia , Relação Dose-Resposta a Droga , Eletroforese em Gel de Ágar , Humanos , Lipoproteínas LDL/efeitos dos fármacos , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
8.
Radiology ; 187(2): 359-61, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8475272

RESUMO

Eight patients had gastrocolic fistulas depicted on barium studies at the authors' hospital during a 10-year period between 1982 and 1992. Seven of those patients (88%) had benign disease, including aspirin-induced gastric ulcers of the greater curvature (n = 4), granulomatous colitis (n = 1), tuberculosis (n = 1), and a penetrating anastomotic ulcer after partial gastrectomy (n = 1). The remaining patient had a malignant gastrocolic fistula caused by carcinoma of the transverse colon. Two patients (25%) experienced classic symptoms of gastrocolic fistulas (ie, feculent vomiting or foul-smelling eructations), but the other six (75%) experienced abdominal pain or other nonspecific clinical findings. In the four patients who were taking aspirin, upper gastrointestinal examinations revealed giant penetrating ulcers of the greater curvature that communicated with the superior border of the transverse colon via a fistula. Three of these patients exhibited marked clinical improvement after conservative medical treatment and did not need surgery. This experience suggests that aspirin-induced gastric ulcers of the greater curvature have become a more common cause of gastrocolic fistulas than is carcinoma of the stomach or transverse colon.


Assuntos
Aspirina/efeitos adversos , Doenças do Colo/induzido quimicamente , Fístula Gástrica/induzido quimicamente , Fístula Intestinal/induzido quimicamente , Adulto , Idoso , Feminino , Fístula Gástrica/diagnóstico por imagem , Fístula Gástrica/etiologia , Humanos , Fístula Intestinal/diagnóstico por imagem , Fístula Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Úlcera Gástrica/induzido quimicamente
9.
Internist ; 33(3): 11-2, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10116709

RESUMO

A Seattle nephrologist cautions against making euthanasia a public policy, citing contemporary concerns over the ethical, legal, medical and societal questions that the issue raises.


Assuntos
Eutanásia Ativa , Eutanásia/legislação & jurisprudência , Intenção , Internacionalidade , Países Baixos , Papel do Médico , Direito a Morrer , Estados Unidos
10.
Sci Total Environ ; 93: 403-10, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2360022

RESUMO

Radiocaesium contamination of dusts from external (road and school yards) and internal (house) environments within Barrow-in-Furness was found to be derived from the primary input event of Chernobyl fallout. The specific activity of radiocaesium in the dust reservoirs studied, decreased exponentially, enabling environmental half-lives to be calculated (190-370 day). The broad similarity of these half-lives indicated that secondary contamination processes, such as atmospheric deposition of resuspended dust, cause all the internal and external reservoirs to be linked into a system encompassing much of Barrow-in-Furness. Mean residence times of external dust were derived from the calculated environmental half-lives and measurements of atmospheric deposition (150-250 day). These mean residence times are dependent on local processes and are thus site specific, whilst the environmental half-lives represent an integration of all the processes operating in Barrow-in-Furness.


Assuntos
Poluentes Radioativos do Ar/análise , Poluentes Atmosféricos/análise , Radioisótopos de Césio/análise , Clima , Poeira/análise , Microclima , Acidentes , Inglaterra , Habitação , Humanos , Reatores Nucleares , Ucrânia , População Urbana
11.
Neurology ; 39(11 Suppl 2): 96-101; discussion 105, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2685655

RESUMO

The combination of carbidopa and levodopa (Sinemet) is a highly effective treatment for the symptoms of Parkinson's disease. However, side effects, such as abnormal involuntary movements, fluctuations in motor performance, and "wearing off" phenomena limit its long-term usefulness in some patients. Open-label studies show that controlled-release Sinemet CR is effective in reducing motor fluctuations. This report discusses the results of a 14-week double-blind crossover study comparing the efficacy and tolerability of standard Sinemet with controlled-release Sinemet CR. Overall, there were no statistically significant differences in efficacy between Sinemet CR and standard Sinemet on any of the major efficacy measures, suggesting a clinical equivalence in terms of treating the symptoms of Parkinson's disease. The study also supports the tolerability of Sinemet CR. In summary, Sinemet CR holds the promise of reducing some disturbing side effects of long-term levodopa therapy, thus achieving optimal control of parkinsonian symptoms.


Assuntos
Antiparkinsonianos/administração & dosagem , Carbidopa/administração & dosagem , Levodopa/administração & dosagem , Doença de Parkinson/tratamento farmacológico , Idoso , Ensaios Clínicos como Assunto , Preparações de Ação Retardada , Método Duplo-Cego , Combinação de Medicamentos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória
12.
N Engl J Med ; 321(3): 158-63, 1989 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-2747747

RESUMO

To examine the effects of erythropoietin on the anemia of chronic renal disease and on the rate of renal deterioration, we administered recombinant human erythropoietin to 17 patients with anemia and progressive renal failure who did not yet require dialysis (serum creatinine level, 353 to 972 mumol per liter [4.0 to 11.0 mg per deciliter]). The dose of erythropoietin (50 to 150 units per kilogram of body weight) was adjusted according to the hematocrit response. In all 17 patients the anemia responded to erythropoietin. The median hematocrit increased from 0.27 to 0.37. The rate of the response depended on the initial erythropoietin dose and was similar to that observed in patients who were on dialysis. Hypertension was present in 14 patients before therapy, developed during therapy in 2 of the normotensive patients, and worsened in 9 patients, who required additional antihypertensive medications. The rate of the decline in renal function, as measured by serial determination of the reciprocal of the serum creatinine level, did not change significantly as the hematocrit rose (P = 0.78 by the paired t-test) during erythropoietin therapy. All the patients reported improvements in appetite, activity level, and sense of well-being. We conclude that erythropoietin therapy is effective in correcting the anemia of patients with progressive renal failure without affecting renal function, although it may be associated with an increase in blood pressure.


Assuntos
Anemia/terapia , Eritropoetina/uso terapêutico , Falência Renal Crônica/complicações , Adulto , Idoso , Anemia/sangue , Anemia/etiologia , Nitrogênio da Ureia Sanguínea , Creatinina/sangue , Feminino , Hematócrito , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico
13.
Mich Med ; 88(4): 7, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2755355
14.
Clin Pharmacol Ther ; 25(5 Pt 1): 514-21, 1979 May.
Artigo em Inglês | MEDLINE | ID: mdl-436355

RESUMO

Kinetic parameters and bioavailability of cefadroxil were studied in 20 subjects with differing renal function as measured by endogenous creatinine clearance (CCr). Two subjects were on hemodialysis. After an overnight fast, each subject ingested two 500-mg capsules of cefadroxil. The peak serum concentration was variable (12 to 57 mg/L) and correlated inversely with the CCr. All but one patient had maximum absorption within 4 hr of ingestion and in most patients the peak was reached within the 2-hr sample. Urinary recovery within 48 hr was 45% to 106% when CCr greater than 8 ml/min. Even in patients with the most severe renal failure (CCr less than 10 ml/min), urine concentrations of cefadroxil were adequate to treat susceptible bacteria. The rate of oral absorption ka, was not affected by the state of renal function and was 0.76 +/- 0.50 hr-1. The apparent distribution volume (V d ext) was 0.28 +/- 0.09 L/kg. The plasma elimination rate was dependent on CCr wih a small fraction of drug being removed by nonrenal routes. Except in advanced renal failure, tubular secretion was present since renal clearance of cefadroxil exceeded CCr. The data suggest that little drug accumulation will occur with the usual 8- to 12-hr dosing schedule except when the CCr is less than 25 ml/min.


Assuntos
Cefalosporinas/metabolismo , Nefropatias/metabolismo , Adulto , Idoso , Cefalosporinas/sangue , Cefalosporinas/urina , Feminino , Humanos , Rim/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos
18.
JAMA ; 235(21): 2316-7, 1976 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-131202

RESUMO

Serum prolactin levels are significantly greater among hypertensive patients receiving reserpine as compared to levels six weeks after discontinuing the treatment (P less than .005). This association between regular, long-term reserpine use and greater prolactin levels may be clinically significant, since an increased incidence of breast cancer has been reported among hypertensive patients receiving reserpine.


Assuntos
Hipertensão/tratamento farmacológico , Prolactina/sangue , Reserpina/farmacologia , Androstenodiona/sangue , Desidroepiandrosterona/sangue , Estradiol/sangue , Estrona/sangue , Feminino , Hormônio do Crescimento/sangue , Humanos , Masculino , Reserpina/uso terapêutico , Estimulação Química , Fatores de Tempo
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