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1.
Clin Lymphoma Myeloma Leuk ; 23(4): 279-290, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36797154

RESUMO

BACKGROUND: Hyperfractionated cyclophosphamide and dexamethasone (HyperCd) alone, or with carfilzomib(K) and/or daratumumab(D), represents a potential treatment option when rapid disease control is needed for patients with aggressive presentations of relapsed/refractory multiple myeloma (RRMM). PATIENTS AND METHODS: This is a single-center, retrospective analysis of adult patients with RRMM who received HyperCd with or without K and/or D between May 1, 2016 and August 1, 2019 at the University of Texas MD Anderson Cancer Center. We here report treatment response and safety outcomes. RESULTS: Data from 97 patients, 12 with plasma cell leukemia (PCL), were reviewed in this analysis. Patients had had a median of 5 prior lines of therapy and received a median of 1 consecutive cycle of hyperCd-based therapy. The overall response rate (ORR) of all patients was 71.8% (HyperCd 75%, HyperCdK 64.3%, D-HyperCd 73.3%, and D-HyperCdK 76.9%). Median progression-free survival and overall survival among all patients was 4.3 months (HyperCd 3.1 months, HyperCdK 4.5 months, D-HyperCd 3.3 months, and D-HyperCdK 6 months) and 9.0 months (HyperCd 7.4 months, HyperCdK 9.0 months, D-HyperCd 7.5 months, and D-HyperCdK 15.2 months), respectively. Grade 3/4 hematologic toxicities were common, thrombocytopenia being the most frequent at 76%. Notably, 29-41% of patients per treatment group had existing grade 3/4 cytopenias at initiation of hyperCd-based therapy. CONCLUSION: HyperCd-based regimens provided rapid disease control among MM patients, even when heavily pre-treated and with few remaining treatment options. Grade 3/4 hematologic toxicities were frequent, but manageable with aggressive supportive care.


Assuntos
Mieloma Múltiplo , Trombocitopenia , Adulto , Humanos , Estudos Retrospectivos , Ciclofosfamida/efeitos adversos , Dexametasona/uso terapêutico , Trombocitopenia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
Ann Oncol ; 27(7): 1317-23, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27091808

RESUMO

BACKGROUND: Brentuximab vedotin (BV) is a key therapeutic agent for patients with relapsed/refractory classical Hodgkin lymphoma (cHL). The outcomes of patients experiencing disease progression after BV are poorly described. PATIENTS AND METHODS: We reviewed our institutional database to identify patients with cHL treated with BV who were either refractory to treatment or experienced disease relapse. We collected clinicopathologic features, treatment details at progression and outcome. RESULTS: One hundred patients met inclusion criteria, with a median age of 32 years (range 18-84) at progression after BV. The median number of treatments before BV was 3 (range 0-9); 71 had prior autologous stem cell transplant. The overall response rate (ORR) to BV was 57%, and the median duration of BV therapy was 3 months (range 1-25). After disease progression post-BV, the most common treatment strategies were investigational agents (n = 30), gemcitabine (n = 15) and bendamustine (n = 12). The cumulative ORR to therapy was 33% (complete response 15%). After a median follow-up of 25 months (range 1-74), the median progression-free (PFS) and overall survival (OS) were 3.5 and 25.2 months, respectively. In multivariate analysis, no factors analyzed were predictive of PFS; age at progression >45 years and serum albumin <40 g/l at disease progression were associated with increased risk of death. Among patients who achieved response to therapy, allogeneic stem cell transplantation was associated with a non-significant trend toward superior OS (P = 0.11). CONCLUSIONS: Patients with BV-resistant cHL have poor outcomes. These data serve as a reference for newer agents active in BV-resistant disease.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Doença de Hodgkin/tratamento farmacológico , Imunoconjugados/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cloridrato de Bendamustina/administração & dosagem , Cloridrato de Bendamustina/efeitos adversos , Brentuximab Vedotin , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Progressão da Doença , Intervalo Livre de Doença , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Humanos , Imunoconjugados/efeitos adversos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Gencitabina
3.
J Chem Phys ; 134(6): 064510, 2011 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-21322708

RESUMO

Reduction-oxidation (redox) reactions of the redox couples An(VI)/An(V), An(V)/An(IV), and An(IV)/An(III), where An is an element in the family of early actinides (U, Np, and Pu), as well as Am(VI)/Am(V) and Am(V)/Am(III), are modeled by combining density functional theory with a generalized Anderson impurity model that accounts for the strong correlations between the 5f electrons. Diagonalization of the Anderson impurity model yields improved estimates for the redox potentials and the propensity of the actinide complexes to disproportionate.


Assuntos
Elementos da Série Actinoide/química , Oxirredução , Teoria Quântica
4.
Colorectal Dis ; 10(5): 498-502, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17949445

RESUMO

BACKGROUND: The role of palliative surgical resection in patients presenting with locally advanced or metastatic colorectal cancer (CRC) is unclear. Resection is often limited to symptomatic management of bleeding, obstruction, perforation or for relief of pain, in patients with an adequate performance status and an expected life span of over several weeks. An exploratory analysis to evaluate the influence of a palliative surgical resection on survival outcome in patients with advanced CRC is reported. METHOD: A retrospective review of medical records of all patients diagnosed with advanced CRC at our institution between the years 1998 and 2003 was undertaken. Tumour registry data were reviewed to identify age, gender, modalities of therapy [i.e. surgery (S), chemotherapy (C), radiation] and overall survival. IRB approval was obtained for this study. RESULTS: One hundred and eighty-five patients were identified. Median age was 67 years (range 30-99). M:F ratio was 1:1. Sixty-two per cent of patients (115/185) underwent a palliative surgical intervention. Median survival of patients who underwent S and those that did not undergo S was 22 and 3 months respectively (P < 0.0001). Forty-eight per cent of patients (79/184) underwent systemic C. Median survival of patients who received C + S, and patients who received C alone was 30 and 15 months respectively (P < 0.0004). Fifty-one per cent of patients who underwent S, received C; 30% of patients who did not undergo S, received C. Chemotherapy data were available on 46 of 79 patients. Patients treated with S + C, and C without S, received a median of 9 and 6 months of therapy respectively. The median number of regimens used were similar in both. CONCLUSION: These exploratory data suggest a positive influence of a palliative resection performed during the disease course of patients with advanced CRC. The increased frequency of utilization and the more prolonged duration of C in the surgically treated patients may in part contribute to this improved survival. This may also be reflective of performance status at the time of diagnosis. Future trials enrolling patients with advanced CRC should prospectively stratify for surgical intervention to further clarify the influence of this modality on the outcome of systemic therapy in this disease.


Assuntos
Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/tratamento farmacológico , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Cuidados Paliativos , Estudos Retrospectivos , Taxa de Sobrevida
5.
J Neurol Neurosurg Psychiatry ; 75(11): 1629-31, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15489403

RESUMO

Hereditary neuropathy with liability to pressure palsy (HNPP) is characterised by recurrent mononeuropathies following minor trauma. We describe a case of fulminant HNPP beginning on the first day of military physical training. Protracted weakness, muscle atrophy, hand contractures, and multifocal sensory loss developed during a further three weeks of basic training. Nerve conduction changes were typical of HNPP, but without segmental slowing. Electromyographically, there was prominent acute denervation in muscles of the hands and right shoulder. Sural nerve biopsy demonstrated tomaculae and remyelination. Genetic testing revealed PMP-22 gene deletion. This case report demonstrates that HNPP can present with rapidly progressive peripheral nerve dysfunction and electrophysiological evidence of focal axonal loss.


Assuntos
Lesão Axonal Difusa/diagnóstico , Transtornos Heredodegenerativos do Sistema Nervoso/diagnóstico , Militares , Síndromes de Compressão Nervosa/diagnóstico , Paralisia/diagnóstico , Doenças do Sistema Nervoso Periférico/diagnóstico , Educação Física e Treinamento , Adulto , Axônios/patologia , Biópsia , Diagnóstico Diferencial , Lesão Axonal Difusa/genética , Feminino , Transtornos Heredodegenerativos do Sistema Nervoso/genética , Humanos , Músculo Esquelético/inervação , Músculo Esquelético/patologia , Proteínas da Mielina/genética , Bainha de Mielina/patologia , Síndromes de Compressão Nervosa/genética , Exame Neurológico , Paralisia/genética , Doenças do Sistema Nervoso Periférico/genética , Degeneração Retrógrada/diagnóstico , Degeneração Retrógrada/genética , Nervo Sural/patologia
6.
Cell Death Differ ; 11(11): 1204-12, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15286682

RESUMO

Mycoplasma fermentans (M. fermentans) was shown to be involved in the alteration of several eukaryotic cell functions (i.e. cytokine production, gene expression), and was suggested as a causative agent in arthritic diseases involving impaired apoptosis. We investigated whether M. fermentans has a pathogenic potential by affecting tumor necrosis factor (TNF)alpha-induced apoptosis in the human myelomonocytic U937 cell line. A significant reduction in the TNFalpha-induced apoptosis (approximately 60%) was demonstrated upon either infection with live M. fermentans or by stimulation with non-live M. fermentans. To investigate the mechanism of M. fermentans antiapoptotic effect, the reduction of mitochondrial transmembrane potential (DeltaPsim) and the protease activity of caspase-8 were measured. In the infected cells, the reduction of DeltaPsim was inhibited (approximately 75%), and an approximately 60% reduction of caspase-8 activity was measured. In conclusion, M. fermentans significantly inhibits TNFalpha-induced apoptosis in U937 cells, and its effect is upstream of the mitochondria and upstream of caspase-8.


Assuntos
Apoptose , Mycoplasma fermentans/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Caspase 8 , Caspases/metabolismo , Ciclo Celular , Separação Celular , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Potenciais da Membrana , Microscopia Confocal , Mitocôndrias/patologia , Monócitos/microbiologia , Monócitos/patologia , Necrose , Fatores de Tempo , Células U937
7.
Circ Res ; 92(4): 453-60, 2003 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-12600893

RESUMO

The alveolar epithelium is composed of alveolar type 1 (AT1) and alveolar type 2 (AT2) cells, which represent approximately 95% and approximately 5% of the alveolar surface area, respectively. Lung liquid clearance is driven by the osmotic gradient generated by the Na,K-ATPase. AT2 cells have been shown to express the alpha1 Na,K-ATPase. We postulated that AT1 cells, because of their larger surface area, should be important in the regulation of active Na+ transport. By immunofluorescence and electron microscopy, we determined that AT1 cells express both the alpha1 and alpha2 Na,K-ATPase isoforms. In isolated, ouabain-perfused rat lungs, the alpha2 Na,K-ATPase in AT1 cells mediated 60% of the basal lung liquid clearance. The beta-adrenergic agonist isoproterenol increased lung liquid clearance by preferentially upregulating the alpha2 Na,K-ATPase protein abundance in the plasma membrane and activity in alveolar epithelial cells (AECs). Rat AECs and human A549 cells were infected with an adenovirus containing the rat Na,K-ATPase alpha2 gene (Adalpha2), which resulted in the overexpression of the alpha2 Na,K-ATPase protein and caused a 2-fold increase in Na,K-ATPase activity. Spontaneously breathing rats were also infected with Adalpha2, which increased alpha2 protein abundance and resulted in a approximately 250% increase in lung liquid clearance. These studies provide the first evidence that alpha2 Na,K-ATPase in AT1 cells contributes to most of the active Na+ transport and lung liquid clearance, which can be further increased by stimulation of the beta-adrenergic receptor or by adenovirus-mediated overexpression of the alpha2 Na,K-ATPase.


Assuntos
Pulmão/metabolismo , Alvéolos Pulmonares/enzimologia , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais , Células Cultivadas , Humanos , Hibridização In Situ , Técnicas In Vitro , Isoenzimas/genética , Isoenzimas/metabolismo , Isoproterenol/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Masculino , Camundongos , Microscopia Imunoeletrônica , Ouabaína/farmacologia , Alvéolos Pulmonares/citologia , Alvéolos Pulmonares/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , ATPase Trocadora de Sódio-Potássio/genética , Organismos Livres de Patógenos Específicos , Células Tumorais Cultivadas
8.
Eur J Med Res ; 7(7): 304-8, 2002 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-12176679

RESUMO

BACKGROUND: Apoptosis and necrosis are two distinct cell death modalities. Polymorphonuclear leukocytes (PMNL) play an important role in pneumonia and little information is available on whether these cells are cleared by necrosis or apoptosis. We therefore compared the proportion of apoptotic PMNL in lung tissues with and without pneumonia. In addition, the association of PMNL apoptosis and mechanical ventilation (MV) was investigated. METHODS: Samples obtained from a pig model developed to tracheobronchial stenting were analysed. Pneumonia was induced with that model in 10 animals (white-Landrace piglets, Pittman-Moore or Göttingen minipigs). Animals were sacrificed when clinical parameters of pneumonia became evident and 17 lung samples could be analysed for histologic evidence of pneumonia, growth of micro-organisms, and the apoptotic index (proportion of apoptotic PMNL over all PMNL in a 400-power field). In addition, lung samples (n = 7) from two pigs without stent implantation on mechanically ventilated for more than 48 h were studied. RESULTS: A total of 9/17 samples (53%) showed histologic evidence of pneumonia, 11/17 (65%) had significant bacterial growth (> 10(3) cfu/g), and 7/17 (41%) fulfilled both criteria. The apoptotic index was not significantly different in samples with and without histologic evidence of pneumonia (pneumonia: 25.3 +/- 6.1% vs. No pneumonia: 25.2 +/- 11.9%; 95%CI: -9.7 - 9.5, p = 0.989) or in samples with and without significant bacterial growth (significant bacterial growth: 23.5+/-9.3% vs. No significant bacterial growth: 28.5+/-8.2%; 95%CI: -4.6 - 16.7; p = 0.284). However, the apoptotic index was higher in samples of pigs, mechanically ventilated for more than 48 h, compared to the stent group (MV: 36.9+/-10.7% vs. Stent: 25.2 +/- 9.0%; 95% CI: -20.5 - -2.9; p = 0.012). CONCLUSION: In an animal model, the proportion of apoptotic PMNL was not different in lung samples with and without histologic or bacterial pneumonia. However, MV for more than 48 h was associated with a higher proportion of apoptotic PMNL in lung tissue. This study may be helpful for the understanding of the evolution of lung tissue damage induced by bacterial pneumonia and MV.


Assuntos
Apoptose , Modelos Animais de Doenças , Pulmão/patologia , Neutrófilos/patologia , Pneumonia Bacteriana/patologia , Animais , Escherichia coli , Marcação In Situ das Extremidades Cortadas , Klebsiella pneumoniae , Pulmão/microbiologia , Respiração Artificial/efeitos adversos , Staphylococcus aureus , Streptococcus , Suínos
10.
JAMA ; 286(22): 2830-8, 2001 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-11735758

RESUMO

CONTEXT: The prevalence and clinical significance of early ischemic changes (EICs) on baseline computed tomography (CT) scan of the head obtained within 3 hours of ischemic stroke are not established. OBJECTIVE: To determine the frequency and significance of EIC on baseline head CT scans in the National Institute of Neurological Disorders and Stroke (NINDS) rt-PA (recombinant tissue plasminogen activator) Stroke Trial. DESIGN AND SETTING: The original study, a randomized controlled trial, took place from January 1991 through October 1994 at 43 sites, during which CT images were obtained within 3 hours of symptom onset and prior to the initiation of rt-PA or placebo. For the current analysis, detailed reevaluation was undertaken after October 1994 of all baseline head CT scans with clinical data available pretreatment (blinded to treatment arm). PATIENTS: Of 624 patients enrolled in the trial, baseline CT scans were retrieved and reviewed for 616 (99%). MAIN OUTCOME MEASURES: Frequency of EICs on baseline CT scans; association of EIC with other baseline variables; effect of EICs on deterioration at 24 hours (>/=4 points increase from the baseline National Institutes of Health Stroke Scale [NIHSS] score); clinical outcome (measured by 4 clinical scales) at 3 months, CT lesion volume at 3 months, death at 90 days; and symptomatic intracranial hemorrhage (ICH) within 36 hours of treatment. RESULTS: The prevalence of EIC on baseline CT in the combined rt-PA and placebo groups was 31% (n = 194). The EIC was significantly associated with baseline NIHSS score (rho = 0.23; P<.001) and time from stroke onset to baseline CT scan (rho = 0.11; P =.007). After adjusting for baseline variables, there was no EIC x treatment interaction detected for any clinical outcome, including deterioration at 24 hours, 4 clinical scales, lesion volume, and death at 90 days (P>/=.25), implying that EIC is unlikely to affect response to rt-PA treatment. After adjusting for NIHSS score (an independent predictor of ICH), no EIC association with symptomatic ICH at 36 hours was detected in the group treated with rt-PA (P>/=.22). CONCLUSIONS: Our analysis suggests that EICs are prevalent within 3 hours of stroke onset and correlate with stroke severity. However, EICs are not independently associated with increased risk of adverse outcome after rt-PA treatment. Patients treated with rt-PA did better whether or not they had EICs, suggesting that EICs on CT scan are not critical to the decision to treat otherwise eligible patients with rt-PA within 3 hours of stroke onset.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Ativadores de Plasminogênio/uso terapêutico , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Modelos Logísticos , Pessoa de Meia-Idade , Distribuição de Poisson , Proteínas Recombinantes , Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/fisiopatologia , Análise de Sobrevida , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento
12.
J Health Care Poor Underserved ; 12(4): 504-14, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11688199

RESUMO

The aim of this study was to determine the impact of reminder systems on appointment nonadherence rates in an low-income inner-city clinic population. A total of 2,304 consenting patients were randomly assigned to one of three groups: (1) automated telephone reminder, (2) postcard reminder, or (3) no reminder. In contrast with research on other populations, the results of this study demonstrated no significant difference in appointment adherence rates among the three groups. To aid in the development of more effective interventions in the future, individuals not attending their scheduled appointments were interviewed by telephone to determine reason for nonadherence.


Assuntos
Agendamento de Consultas , Cooperação do Paciente , Sistemas de Alerta , Humanos , Estados Unidos , População Urbana
13.
Surgery ; 130(2): 289-95, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11490362

RESUMO

BACKGROUND: We used a Web-based evaluation system to institute specific changes to various clinical teaching services in our integrated residency in an effort to optimize the overall quality of the educational experience and measured the resident satisfaction in these rotations. METHODS: Residents rated 8 categories of experience on a scale of 1 to 5 (maximum summation score, 40 points). Data were analyzed by t-test for equality of means. A probability value of less than.05 was considered significant. RESULTS: Compliance with completion of the evaluations was 100%. The Chronbach's alpha reliability coefficient of the tool was 0.826. Tukey's estimate of power to achieve additivity was 1.5. Six under-performing services were re-engineered with prominent effects on 7 postgraduate year (PGY) rotations. On 2 general surgery services at 1 hospital, the workload was redistributed, and a dedicated team teaching time was instituted (PGY-3 [a]: before, 22 points/after, 31 points; P =.003; PGY-3 [b]: before, 25 points/after, 31 points; P =.004; PGY-1: before, 24 points/after, 29 points; P =.07). A general surgery service at another hospital redistributed coverage of the attending surgeons to create a nonteaching service (PGY-1: before, 22 points/-after, 27 points; P =.01). The transplantation service (PGY-3) was examined, and the role of the point was redefined (before, 24 points/after, 31 points; P =.01). One vascular service (PGY-2) redistributed cases and workload (before, 27 points/after, 22 points; P =.07). The vascular PGY-2 position was eliminated and replaced by a mid-level practitioner. The cardiothoracic service (PGY-1) rotation was converted into a preceptorship (before, 23 points/after, 30 points; P =.015). CONCLUSIONS: A web-based clinical rotation evaluation provides a means for the assessment of the impact of programmatic changes while preserving resident anonymity and maintaining accountability.


Assuntos
Cirurgia Geral/educação , Internet/organização & administração , Internato e Residência/organização & administração , Internato e Residência/normas , Estudantes de Medicina/psicologia , Humanos
15.
Am J Hematol ; 66(2): 151-2, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11421298

RESUMO

Intravenous gammaglobulins are used for the treatment of various auto-immune hematological disorders. Renal failure is a relatively rare, but an increasingly recognized side effect of gammaglobulin therapy. Although the renal failure is usually reversible, renal replacement therapy is required occasionally. A high index of suspicion, early recognition and appropriate intervention can prevent this complication. We herewith describe two patients with an immune hematological disorder, who developed acute renal failure after treatment with intravenous gammaglobulins. A brief review of the possible risk factors, pathophysiology and management of this complication is provided.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Imunoglobulinas Intravenosas/efeitos adversos , Injúria Renal Aguda/etiologia , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/complicações , Anemia Hemolítica Autoimune/tratamento farmacológico , Feminino , Humanos , Masculino , Púrpura Trombocitopênica Idiopática/complicações , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Fatores de Risco , gama-Globulinas/administração & dosagem , gama-Globulinas/efeitos adversos
16.
Hear Res ; 154(1-2): 12-25, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11423211

RESUMO

Histological and immunohistochemical analyses of head and respiratory structures in bullfrog (Rana catesbeiana) tadpoles were undertaken to address the hypothesis that the bronchial columella (BC) is the primary sound conduction pathway in these larval anurans. In postembryonic tadpoles, the BC is composed of fibroblasts surrounded by a Type I collagen matrix, with Type II collagen located in basement membranes at the distal ends. It provides a highly flexible tendon-like attachment between the round window and the membranous sac of the primary bronchus of the ipsilateral lung. As the animals approach metamorphic climax stages, the fibroblasts decrease in number and the BC becomes almost exclusively collagenous. During metamorphic climax, the BC degenerates and is completely resorbed by the time the animal becomes a postmetamorphic froglet. At all larval stages examined, the BC is structurally and immunohistochemically different from both the opercularis muscle of tadpoles and the tympanic columella (stapes homolog) of postmetamorphic animals. These observations suggest that the BC may not be rigid enough to provide an effective coupling between the lungs and the round window. An alternative hypothesis for the function of the BC, based on its structure, is presented.


Assuntos
Orelha/crescimento & desenvolvimento , Rana catesbeiana/crescimento & desenvolvimento , Animais , Brônquios/anatomia & histologia , Brônquios/crescimento & desenvolvimento , Brônquios/fisiologia , Orelha/anatomia & histologia , Orelha/fisiologia , Audição/fisiologia , Imuno-Histoquímica , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Larva/fisiologia , Metamorfose Biológica , Modelos Biológicos , Rana catesbeiana/anatomia & histologia , Rana catesbeiana/fisiologia
17.
Am J Respir Cell Mol Biol ; 24(4): 436-41, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11306437

RESUMO

To determine whether overexpression of antioxidant enzymes in lung epithelial cells prevents damage from oxidant injury, stable cell lines were generated with complementary DNAs encoding manganese superoxide dismutase (MnSOD) and/or catalase (CAT). Cell lines overexpressing MnSOD, CAT, or MnSOD + CAT were assessed for tolerance to hyperoxia or paraquat. After exposure to 95% O(2) for 10 d, 44 to 57% of cells overexpressing both MnSOD and CAT and 37 to 47% of cells overexpressing MnSOD alone were viable compared with 7 to 12% of empty vector or parental cells (P < 0.05). To assess if viable cells were capable of cell division after hyperoxic exposures (up to 5 d), a clonogenicity assay was performed. The clonogenic potential of cells overexpressing MnSOD + CAT and MnSOD alone were significantly better than those expressing CAT alone or empty vector controls. In addition, 54 to 72% of cells overexpressing both MnSOD and CAT survived in 1 mM paraquat compared with 58 to 73% with MnSOD alone and 27% with control cells. Overexpression of CAT alone did not improve survival in hyperoxia or paraquat. The combination of MnSOD + CAT did not provide additional protection from paraquat. Data demonstrate that overexpression of MnSOD protects cells from oxidant injury and CAT offers additional protection from hyperoxic injury when co-expressed with MnSOD.


Assuntos
Células Epiteliais/enzimologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Pulmão/citologia , Estresse Oxidativo/fisiologia , Superóxido Dismutase/genética , Catalase/genética , Catalase/metabolismo , Células Epiteliais/citologia , Células HeLa , Herbicidas/farmacologia , Humanos , Hiperóxia/fisiopatologia , Pulmão/metabolismo , Oxidantes/farmacologia , Paraquat/farmacologia , RNA Mensageiro/análise , Superóxido Dismutase/metabolismo , Transgenes/fisiologia
19.
J Biol Chem ; 276(1): 569-75, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11034997

RESUMO

It has previously been shown that hyperoxia induces nonapoptotic cell death in cultured lung epithelial cells, whereas hydrogen peroxide (H(2)O(2)) and paraquat cause apoptosis. To test whether pathways leading to oxidative apoptosis in epithelial cells are sensitive to molecular O(2), A549 cells were exposed to 95% O(2) prior to exposure to lethal concentrations of H(2)O(2). The extent of H(2)O(2)-induced apoptosis was significantly reduced in cells preexposed to hyperoxia compared with room-air controls. Preexposure of the hyperoxia-resistant HeLa-80 cell line to 80% O(2) also inhibited oxidant-induced apoptosis, suggesting that this inhibition is not due to O(2) toxicity. Because hyperoxia generates reactive oxygen species and activates the redox-sensitive transcription factor nuclear factor kappa B (NF-kappa B), the role of antioxidant enzymes and NF-kappa B were examined in this inhibitory process. The onset of inhibition appeared to be directly related to the degradation of I kappa B and subsequent activation of NF-kappa B (either by hyperoxia or TNF-alpha), whereas no significant up-regulation of endogenous antioxidant enzyme activities was found. In addition, suppression of NF-kappa B activities by transfecting A549 cells with a dominant-negative mutant construct of I kappa B significantly augmented the extent of H(2)O(2)-induced apoptosis. These data suggest that hyperoxia inhibits oxidant-induced apoptosis and that this inhibition is mediated by NF-kappa B.


Assuntos
Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Oxidantes/antagonistas & inibidores , Oxigênio/farmacologia , Antioxidantes/metabolismo , Grupo dos Citocromos c/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Peróxido de Hidrogênio/antagonistas & inibidores , Peróxido de Hidrogênio/farmacologia , Quinase I-kappa B , Marcação In Situ das Extremidades Cortadas , Pulmão/metabolismo , NF-kappa B/metabolismo , Oxidantes/farmacologia , Oxigênio/toxicidade , Paraquat/antagonistas & inibidores , Paraquat/farmacologia , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/efeitos dos fármacos , Xantina Oxidase/metabolismo
20.
Outcomes Manag Nurs Pract ; 5(3): 121-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11898672

RESUMO

Elderly patients (n = 121) with hip fracture were followed to determine if: (1) outcomes measured 12 months post-fracture differed significantly from pre-fracture measures, and (2) patient characteristics on hospital admission predicted three outcomes (site of residence, function, and walking status) 12 months later. At 12 months fewer patients resided at home. They had declined functionally. Baseline cognition, residence site, function, and walking individually predicted outcomes. However, outcomes were predicted best by multiple variables. These findings can be used to educate patients, their families, and the public on outcomes and their determinants after hip fracture.


Assuntos
Fraturas do Quadril/reabilitação , Avaliação de Resultados em Cuidados de Saúde , Atividades Cotidianas , Idoso , Distribuição de Qui-Quadrado , Feminino , Avaliação Geriátrica , Fraturas do Quadril/psicologia , Humanos , Masculino , Avaliação em Enfermagem , Valor Preditivo dos Testes , Análise de Regressão , Fatores de Risco
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