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1.
Gynecol Oncol ; 155(2): 186-191, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31519320

RESUMO

OBJECTIVE: The AGO-OVAR16 study was designed to test the efficacy, safety, and tolerability of pazopanib maintenance after first-line chemotherapy in patients with newly diagnosed advanced ovarian cancer (AOC). METHODS: Nine hundred and forty patients with histologically confirmed AOC, International Federation of Gynecology and Obstetrics (FIGO) stage II-IV, were randomized in a 1:1 ratio to receive either 800 mg pazopanib once daily or placebo for up to 24 months, unless there was disease progression, toxicity, withdrawal of consent, or death. The primary endpoint (investigator-assessed progression-free survival [PFS]) was met and previously reported. The results of final analyses of overall survival (OS) are reported here. RESULTS: A third OS interim analysis showed futility and led to study closure and a final OS analysis after last patient last visit. At the time of the final OS analysis, 494 (89.7% of the planned 551) events had occurred. No difference was observed in OS between pazopanib and placebo. The hazard ratio (HR) was 0.960 (95% confidence interval [CI]: 0.805-1.145), and the median OS from randomization was 59.1 months in pazopanib and 64.0 months in placebo arms. For the East Asian patients, similar to the first three interim OS analyses, a numerical negative trend was observed favoring placebo (HR, 1.332; 95% CI: 0.863-2.054). Exploratory analyses showed a trend for a longer time to first subsequent anti-cancer therapy or death with pazopanib over placebo (HR, 0.829; 95% CI: 0.713-0.965), with a median estimate of 19.0 and 14.5 months, respectively. No new safety signals were observed. CONCLUSION: Although pazopanib prolonged PFS, this was not associated with improvement in median OS. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov: NCT00866697.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Carcinoma Epitelial do Ovário/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Pirimidinas/administração & dosagem , Sulfonamidas/administração & dosagem , Adulto , Idoso , Carcinoma Epitelial do Ovário/mortalidade , Intervalo Livre de Doença , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Indazóis , Pessoa de Meia-Idade , Neoplasias Ovarianas/mortalidade , Qualidade de Vida , Resultado do Tratamento , Adulto Jovem
2.
Ann Oncol ; 29(3): 737-743, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29267856

RESUMO

Background: Health-related quality of life (HRQoL) was a secondary end point in AGO-OVAR 16, which randomized 940 patients with EOC after first-line chemotherapy to maintenance pazopanib (PZ) or placebo (P). Additional post hoc analyses were carried out to investigate additional patient-centered end points. Patients and methods: HRQoL was measured with EORTC-QLQ-C30, QLQ-OV28 and EQ-5D-3L. Pre-specified end points included mean differences in HRQoL between treatment arms. Exploratory analyses included quality-adjusted progression-free survival (QAPFS), impact of specific symptoms and progressive disease (PD) on HRQoL and time to second-line chemotherapy. The objective was to provide clinical perspective to the significant median PFS gain of 5.6 months with PZ. Results: There were statistically significant differences between PZ and P in QLQ-C30 global health status [5.5 points; 95% confidence interval (CI), 0.7-10.4, P = 0.024] from baseline to 25 months, but not EQ-5D-3L (0.018 points; 95% CI - 0.033 to 0.069, P = 0.485). The impact of diarrhea was captured in QLQ-OV28 Abdominal/GI-Symptoms scale (8.1 points; 95% CI 3.6-12.5, P = 0.001). QAPFS was 386 days (95% CI 366-404 days) with PZ versus 359 days (95% CI 338-379 days) with placebo (P = 0.052). PD was associated with a decline in HRQoL (P < 0.0001). Median time to second-line chemotherapy was 19.7 months with PZ and 15.0 months with P [hazard ratio (HR) 0.72, 95% CI 0.69-0.86, P = 0.0001]. Conclusions: There were small to no significant mean score differences in global HRQoL and EQ5D-3L between PZ and placebo, respectively, despite the increased toxicity of PZ. Exploratory end points including QAPFS, impact of specific symptoms on HRQoL during treatment and at PD help place the PFS gain with PZ in context and interpret the results. Additional patient-centered end points should be considered in trials of maintenance therapy in EOC beyond mean differences in HRQoL scores alone, to support the benefit to patients of prolongation of PFS. Clinical Trials Registration Number: NCT00866697.


Assuntos
Antineoplásicos/efeitos adversos , Carcinoma Epitelial do Ovário/tratamento farmacológico , Quimioterapia de Manutenção/efeitos adversos , Neoplasias Ovarianas/tratamento farmacológico , Pirimidinas/efeitos adversos , Qualidade de Vida , Sulfonamidas/efeitos adversos , Adulto , Inibidores da Angiogênese/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Indazóis , Quimioterapia de Manutenção/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Medidas de Resultados Relatados pelo Paciente , Intervalo Livre de Progressão , Tempo para o Tratamento
4.
Ir Med J ; 106(9): 262, 264-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24416846

RESUMO

UNLABELLED: Irish breast cancer survivor's needs have not been studied. Physical, psychological, social and spiritual concerns were investigated. Patient satisfaction with hospital discharge, GP follow-up, and the benefit of a discharge pack was investigated. A cohort of patients from the South East Cancer Centre was identified. INCLUSION CRITERIA: localized breast cancer, completion of adjuvant therapy, GP-led follow-up in the last 5 years. An anonymous questionnaire was developed, and ethical approval obtained. Subgroup analyses for age and time since diagnosis and discharge were completed. 80 patients were identified. 44 patients (55%) completed the questionnaire, 5 (6%) were excluded. Commonest concerns included: fatigue (51%), fear of recurrence (69%) and second cancers concerns (69%) 23 (59%) and 25 patients (64%) were satisfied with discharge and GP follow-up respectively. 27 patients (67%) reported benefit from a discharge pack. Irish breast cancer survivors had concerns, and were satisfied with GP follow-up.


Assuntos
Neoplasias da Mama/psicologia , Necessidades e Demandas de Serviços de Saúde , Sobreviventes/psicologia , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Feminino , Humanos , Irlanda/epidemiologia , Pessoa de Meia-Idade , Satisfação do Paciente , Inquéritos e Questionários
5.
Front Immunol ; 13: 871217, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35514990

RESUMO

A man in his early 50s presented with small bowel obstruction, requiring emergency laparoscopic small bowel resection for the metastatic melanoma of the jejunum with no identifiable primary lesion. One week after his first treatment with ipilimumab and nivolumab, he presented with diffuse abdominal pain, constipation, and fatigue. A computerized tomography scan did not identify a cause for his symptoms. This was rapidly followed by thrombocytopenia on day 11 and then anemia. He commenced intravenous corticosteroids for a suspected diagnosis of immune-related thrombocytopenia. On day 15, a generalized onset motor seizure occurred, and despite plasmapheresis later that day, the patient died from fatal immune-related thrombotic thrombocytopenic purpura (TTP). This was confirmed with suppressed ADAMTS13 (<5%) testing on day 14. Immune-related TTP is a rare and, in this case, fatal immune- related adverse event. Further studies are required to identify additional immunosuppressive management for immune-related TTP.


Assuntos
Melanoma , Segunda Neoplasia Primária , Púrpura Trombocitopênica Idiopática , Púrpura Trombocitopênica Trombótica , Humanos , Fatores Imunológicos , Imunoterapia , Ipilimumab/efeitos adversos , Masculino , Melanoma/tratamento farmacológico , Nivolumabe/efeitos adversos , Púrpura Trombocitopênica Trombótica/diagnóstico
6.
Science ; 282(5386): 117-21, 1998 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-9756475

RESUMO

Heterotrimeric guanosine 5'-triphosphate (GTP)-binding proteins (G proteins) are deactivated by hydrolysis of the GTP that they bind when activated by transmembrane receptors. Transducin, the G protein that relays visual excitation from rhodopsin to the cyclic guanosine 3',5'-monophosphate phosphodiesterase (PDE) in retinal photoreceptors, must be deactivated for the light response to recover. A point mutation in the gamma subunit of PDE impaired transducin-PDE interactions and slowed the recovery rate of the flash response in transgenic mouse rods. These results indicate that the normal deactivation of transducin in vivo requires the G protein to interact with its target enzyme.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/metabolismo , Segmento Externo da Célula Bastonete/metabolismo , Transducina/metabolismo , Visão Ocular , 3',5'-GMP Cíclico Fosfodiesterases/genética , Animais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 6 , Eletrorretinografia , Ativação Enzimática , Feminino , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanosina Trifosfato/metabolismo , Hidrólise , Luz , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mutação Puntual , Retina/citologia , Retina/fisiologia , Degeneração Retiniana , Transgenes
7.
Science ; 255(5048): 1098-105, 1992 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-1546311

RESUMO

Many organisms construct structural ceramic (biomineral) composites from seemingly mundane materials; cell-mediated processes control both the nucleation and growth of mineral and the development of composite microarchitecture. Living systems fabricate biocomposites by: (i) confining biomineralization within specific subunit compartments; (ii) producing a specific mineral with defined crystal size and orientation; and (iii) packaging many incremental units together in a moving front process to form fully densified, macroscopic structures. By adapting biological principles, materials scientists are attempting to produce novel materials. To date, neither the elegance of the biomineral assembly mechanisms nor the intricate composite microarchitectures have been duplicated by nonbiological processing. However, substantial progress has been made in the understanding of how biomineralization occurs, and the first steps are now being taken to exploit the basic principles involved.


Assuntos
Cerâmica , Animais , Matriz Óssea , Calcificação Fisiológica , Galinhas , Cristalografia
8.
J Neurosci ; 21(15): 5449-60, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11466416

RESUMO

A dominant form of human congenital nightblindness is caused by a gly90-->asp (G90D) mutation in rhodopsin. G90D has been shown to activate the phototransduction cascade in the absence of light in vitro. Such constitutive activity of G90D rhodopsin in vivo would desensitize rod photoreceptors and lead to nightblindness. In contrast, other rhodopsin mutations typically give rise to nightblindness by causing rod cell death. Thus, the proposed desensitization without rod degeneration would be a novel mechanism for this disorder. To explore this possibility, we induced mice to express G90D opsin in their rods and then examined rod function and morphology, after first crossing the transgenic animals with rhodopsin knock-out mice to obtain appropriate levels of opsin expression. The G90D mouse opsin bound the chromophore and formed a bleachable visual pigment with lambda(max) of 492 nm that supported rod photoresponses. (G+/-, R+/-) retinas, heterozygous for both G90D and wild-type (WT) rhodopsin, possessed normal numbers of photoreceptors and had a normal rhodopsin complement but exhibited considerable loss of rod sensitivity as measured electroretinographically. The rod photoresponses were desensitized, and the response time to peak was faster than in (R+/-) animals. An equivalent desensitization resulted by exposing WT retinas to a background light producing 82 photoisomerizations rod(-1) sec(-1), suggesting that G90D rods in darkness act as if they are partially "light-adapted." Adding a second G90D allele gave (G+/+, R+/-) animals that exhibited a further increase of equivalent background light level but had no rod cell loss by 24 weeks of age. (G+/+, R-/-) retinas that express only the mutant rhodopsin develop normal rod outer segments and show minimal rod cell loss even at 1 year of age. We conclude that G90D is constitutively active in mouse rods in vivo but that it does not cause significant rod degeneration. Instead, G90D desensitizes rods by a process equivalent to light adaptation.


Assuntos
Adaptação Ocular/genética , Cegueira Noturna/etiologia , Cegueira Noturna/fisiopatologia , Células Fotorreceptoras Retinianas Bastonetes/fisiopatologia , Rodopsina/metabolismo , Alelos , Substituição de Aminoácidos , Animais , Contagem de Células , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Eletrorretinografia , Genes Dominantes , Genótipo , Heterozigoto , Homozigoto , Humanos , Imuno-Histoquímica , Luz , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Retina/patologia , Retina/fisiopatologia , Células Fotorreceptoras Retinianas Bastonetes/patologia , Rodopsina/genética , Rodopsina/efeitos da radiação
9.
J Gen Physiol ; 111(1): 39-51, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9417133

RESUMO

Light adaptation in vertebrate photoreceptors is thought to be mediated through a number of biochemical feedback reactions that reduce the sensitivity of the photoreceptor and accelerate the kinetics of the photoresponse. Ca2+ plays a major role in this process by regulating several components of the phototransduction cascade. Guanylate cyclase and rhodopsin kinase are suggested to be the major sites regulated by Ca2+. Recently, it was proposed that cGMP may be another messenger of light adaptation since it is able to regulate the rate of transducin GTPase and thus the lifetime of activated cGMP phosphodiesterase. Here we report measurements of the rates at which the changes in Ca2+ and cGMP are followed by the changes in the rates of corresponding enzymatic reactions in frog rod outer segments. Our data indicate that there is a temporal hierarchy among reactions that underlie light adaptation. Guanylate cyclase activity and rhodopsin phosphorylation respond to changes in Ca2+ very rapidly, on a subsecond time scale. This enables them to accelerate the falling phase of the flash response and to modulate flash sensitivity during continuous illumination. To the contrary, the acceleration of transducin GTPase, even after significant reduction in cGMP, occurs over several tens of seconds. It is substantially delayed by the slow dissociation of cGMP from the noncatalytic sites for cGMP binding located on cGMP phosphodiesterase. Therefore, cGMP-dependent regulation of transducin GTPase is likely to occur only during prolonged bright illumination.


Assuntos
Adaptação Ocular/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/enzimologia , Animais , Sítios de Ligação/fisiologia , Cálcio/metabolismo , Calmodulina/farmacologia , GMP Cíclico/metabolismo , Citoplasma/enzimologia , Ativação Enzimática , Proteínas do Olho/metabolismo , Receptor Quinase 1 Acoplada a Proteína G , GTP Fosfo-Hidrolases/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato)/farmacologia , Guanilato Ciclase/metabolismo , Cinética , Diester Fosfórico Hidrolases/química , Diester Fosfórico Hidrolases/metabolismo , Proteínas Quinases/metabolismo , Rana catesbeiana , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Transducina/metabolismo , Vertebrados
10.
J Gen Physiol ; 103(6): 1071-98, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7931138

RESUMO

Cyclic GMP hydrolysis by the phosphodiesterase (PDE) of retinal rod outer segments (ROS) is a key amplification step in phototransduction. Definitive estimates of the turnover number, kcat, and of the Km are crucial to quantifying the amplification contributed by the PDE. Published estimates for these kinetic parameters vary widely; moreover, light-dependent changes in the Km of PDE have been reported. The experiments and analyses reported here account for most observed variations in apparent Km, and they lead to definitive estimates of the intrinsic kinetic parameters in amphibian rods. We first obtained a new and highly accurate estimate of the ratio of holo-PDE to rhodopsin in the amphibian ROS, 1:270. We then estimated the apparent kinetic parameters of light-activated PDE of suspensions of disrupted frog ROS whose structural integrity was systematically varied. In the most severely disrupted ROS preparation, we found Km = 95 microM and kcat = 4,400 cGMP.s-1. In suspensions of disc-stack fragments of greater integrity, the apparent Km increased to approximately 600 microM, though kcat remained unchanged. In contrast, the Km for cAMP was not shifted in the disc stack preparations. A theoretical analysis shows that the elevated apparent Km of suspensions of disc stacks can be explained as a consequence of diffusion with hydrolysis in the disc stack, which causes active PDEs nearer the center of the stack to be exposed to a lower concentration of cyclic GMP than PDEs at the disc stack rim. The analysis predicts our observation that the apparent Km for cGMP is elevated with no accompanying decrease in kcat. The analysis also predicts the lack of a Km shift for cAMP and the previously reported light dependence of the apparent Km for cGMP. We conclude that the intrinsic kinetic parameters of the PDE do not vary with light or structural integrity, and are those of the most severely disrupted disc stacks.


Assuntos
3',5'-GMP Cíclico Fosfodiesterases/farmacocinética , Segmento Externo da Célula Bastonete/fisiologia , Segmento Externo da Célula Bastonete/ultraestrutura , 3',5'-GMP Cíclico Fosfodiesterases/análise , 3',5'-GMP Cíclico Fosfodiesterases/fisiologia , Animais , Membrana Celular/enzimologia , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Hidrólise , Matemática , Modelos Biológicos , Rana catesbeiana , Rodopsina/análise , Rodopsina/farmacocinética , Rodopsina/fisiologia
11.
Neurology ; 56(3): 299-303, 2001 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-11171892

RESUMO

OBJECTIVE: To characterize the clinical and neuroradiologic features of a new spinocerebellar ataxia, SCA-12, in the index family. BACKGROUND: The authors recently linked SCA-12 to a novel CAG repeat expansion on chromosome 5q31-33 that is located within the 5' region of PPP2R2B, a gene encoding a brain-specific regulatory subunit of protein phosphatase 2A. METHODS: Neurologic features of the proband and nine symptomatic relatives in the first SCA-12 family were compiled and, in some individuals, related to changes found on brain MRI or CT. RESULTS: SCA-12 typically presented in the 4th decade of life with action tremor of the head or arms (present in 10/10 of the affected individuals). Hyperreflexia (8/10) was a common feature, and cerebellar signs (8/10), including ataxia, dysmetria, and dysarthria, developed gradually but were less prominent and disabling than cerebellar dysfunction in other SCA. Subtle parkinsonian features (9/10) and dementia (2/10) were observed in later stages of SCA-12, and psychiatric symptoms, including depression, anxiety, or delusions, were present in some affected family members (4/10). Two individuals studied had nondisabling neurologic signs neonatally, including nystagmus and lower extremity dystonia. Brain images of affected individuals revealed cerebral and cerebellar atrophy. CONCLUSIONS: SCA-12 is a slowly progressive, autosomal dominant, neurodegenerative disorder that differs from other SCA in that it typically presents with action tremor in patients in their mid 30s and usually includes hyperreflexia and subtle parkinsonian signs. Cerebellar dysfunction, including gait ataxia, is relatively nondisabling, and cognitive or psychiatric disorders may occur. Neuroradiologic studies reveal atrophy of the cerebellum and cerebral cortex.


Assuntos
Ataxia Cerebelar/genética , Tremor/fisiopatologia , Expansão das Repetições de Trinucleotídeos/genética , Encéfalo/patologia , Ataxia Cerebelar/patologia , Ataxia Cerebelar/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Linhagem
12.
Semin Oncol ; 25(4 Suppl 9): 51-4, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9728585

RESUMO

Gemcitabine has demonstrated single-agent activity in advanced, incurable non-small cell lung cancer, yielding response rates of > or =20%, and, in combination with cisplatin, response rates of 30% to 60%. Carboplatin causes much less nonhematologic toxicity than cisplatin, and initial therapy with carboplatin yields equivalent survival in advanced non-small cell lung cancer compared with cisplatin combinations and other cisplatin analogs, despite a lower response rate. Carmichael and colleagues have identified a maximum tolerated dose of carboplatin of area under the curve 5.2 mg/mL/min administered monthly in combination with gemcitabine 1,000 mg/m2 on days 1, 8, and 15. This combination produced a response rate of 31% and a median survival of 45 weeks in 13 evaluable patients. A subsequent phase I evaluation reversing the carboplatin and gemcitabine sequence (gemcitabine --> carboplatin day 1) demonstrated no difference in toxicities, pharmacodynamics, or maximum tolerated dose. At Fox Chase Cancer Center and elsewhere, similar phase I trials will determine the maximum tolerated doses of each agent in combination using a compressed schedule with carboplatin administered every 3 weeks and gemcitabine given on days 1 and 8 only.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Carboplatina/farmacocinética , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacocinética , Humanos , Gencitabina
13.
Semin Oncol ; 26(1 Suppl 4): 12-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10201516

RESUMO

Gemcitabine has demonstrated single-agent activity in advanced, incurable non-small cell lung cancer, yielding response rates of > or =20%. In combination with cisplatin, response rates of 30% to 60% and encouraging survival have been observed. Carboplatin causes much less nonhematologic toxicity than cisplatin. In a phase III Eastern Cooperative Oncology Group trial, initial therapy with carboplatin yielded superior survival in advanced non-small cell lung cancer compared with cisplatin combinations and other cisplatin analogs, despite a lower response rate. Thus, studies designed to identify optimal dose schedules for a combination of gemcitabine plus carboplatin are clearly warranted. Carmichael et al from the United Kingdom have identified a maximum tolerated dose of carboplatin of area under the curve of 5.2 mg/mL/min administered on day I followed by gemcitabine 1,000 mg/m2 on days 1, 8, and 15 of a 28-day cycle. This combination produced a response rate of 31% and a median survival of 10.5 months in 13 evaluable patients. A subsequent phase I evaluation reversing the carboplatin and gemcitabine sequence (gemcitabine preceding carboplatin on day 1) demonstrated no difference in toxicities, pharmacodynamics, or maximum tolerated dose. Other investigators have identified similar promising results with this regimen, although one North American investigator has observed untoward toxicity in a small number of patients using a standard 28-day dose schedule with gemcitabine administered on days, 1, 8, and 15. Day-15 gemcitabine dosing is problematic and may contribute to excessive thrombocytopenia when gemcitabine is combined with carboplatin. The ongoing phase I/II trials reviewed here have focused on a compressed 21-day schedule, with carboplatin administered every 3 weeks and gemcitabine given on days 1 and 8 only.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Desoxicitidina/administração & dosagem , Esquema de Medicação , Humanos , Gencitabina
14.
J Biomed Mater Res A ; 67(4): 1155-62, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14624501

RESUMO

Calcium phosphate and bovine serum albumin were coprecipitated (under physiological conditions of temperature and pH) upon the surfaces of titanium-alloy samples, which thereby became coated with a dense, proteinaceous mineral layer 30-50 microm in thickness. Dissolution of the inorganic phase by treatment with acidic saline yielded a self-supporting protein scaffold, 7-10 microm in thickness. Energy-dispersive X-ray analysis and Fourier-transform infrared spectroscopy confirmed the absence of inorganic components from the demineralized albumin scaffolds. When titanium-alloy samples bearing these demineralized protein scaffolds were immersed in a supersaturated solution of calcium phosphate (again at physiological temperature and pH), they remineralized. These redux albumin-calcium phosphate layers corresponded in thickness to the original coatings. When titanium-alloy discs bearing the demineralized protein scaffolds were implanted ectopically (subcutaneously) in mice, they, too, remineralized. No uniform mineral layer was deposited upon the surfaces of naked titanium-alloy implants. To the best of our knowledge, this is the first demonstration of remineralization within the interstices of a noncollagenous protein scaffold, either in vitro or in vivo.


Assuntos
Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/química , Soroalbumina Bovina/química , Ligas/química , Animais , Bovinos , Concentração de Íons de Hidrogênio , Teste de Materiais , Camundongos , Camundongos Nus , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura , Titânio/química
15.
Chem Biol Interact ; 111-112: 213-24, 1998 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-9679556

RESUMO

The greater affinity of electrophiles for thiol groups than for hydroxyl or amine groups provides a teleological basis for the evolution of this mechanism to assist in the maintenance of cellular homeostasis. As the most abundant cellular non-protein thiol, glutathione (GSH) is pivotal in the protection of cells from electrophiles created during normal respiration and protection after exposure to environmental mutagens. Mutagens and many anti-cancer drugs, e.g. cisplatin and alkylating agents, have the same target, i.e. DNA. This suggested that one mechanism by which cancer cells might circumvent the action of cancer chemotherapeutic agents would be by increasing their cellular GSH and/or enhanced conjugation of these drugs to this abundant tripeptide. This chapter describes the abundant preclinical data that support this mechanism of resistance to platinum drugs and alkylating agents. This data was the rationale for the development of pharmacologic strategies to lower GSH and inactivate the gluathione-S-transferases to make anti-cancer drugs more effective. The positive outcome of preclinical studies to lower GSH and enhance the activity of melaphalan are described as is the status of on going clinical trials built around this data.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Resistência a Medicamentos/fisiologia , Glutationa/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Butionina Sulfoximina/administração & dosagem , Butionina Sulfoximina/farmacocinética , Butionina Sulfoximina/farmacologia , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Melfalan/administração & dosagem , Melfalan/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo
17.
J Bone Joint Surg Br ; 82(5): 719-23, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10963172

RESUMO

We diagnosed 50 patients (58 shoulders) with a mean age at presentation of 17.3 years, as having involuntary positional instability of the shoulder. They were managed by a programme consisting of a careful explanation, analysis of abnormal muscle couples and then muscle retraining carried out by a specialist physiotherapist. The mean follow-up was two years. Six shoulders had a poor result, but 52 were graded as good to excellent. Nine patients (12 shoulders) relapsed and required further episodes of retraining. In our experience, involuntary positional instability of the shoulder causes symptoms which interfere with normal activities; these can be controlled by a treatment plan of retraining of the muscle pattern with functional benefit. Only 19 of the patients were referred with a diagnosis of positional instability. There should be more awareness of this rather uncommon condition. Surgery is not indicated in these patients.


Assuntos
Instabilidade Articular/reabilitação , Modalidades de Fisioterapia , Articulação do Ombro , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Resultado do Tratamento
18.
J Bone Joint Surg Br ; 71(2): 246-51, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2494186

RESUMO

We reviewed 47 patients with neurofibromatosis and dystrophic spinal deformities; 32 of these patients had been untreated for an average of 3.6 years and in them the natural history was studied. The commonest pattern of deformity at the time of presentation was a short angular thoracic scoliosis, but with progression the angle of kyphosis also increased. Deterioration during childhood was usual but its rate was variable. Severe dystrophic changes in the apical vertebrae and in particular anterior scalloping have a poor prognosis for deterioration. The dystrophic spinal deformity of neurofibromatosis requires early surgical stabilisation which should be by combined anterior and posterior fusion if there is an abnormal angle of kyphosis or severely dystrophic apical vertebrae. Some carefully selected patients can be treated by posterior fusion and instrumentation alone.


Assuntos
Neurofibromatose 1/complicações , Escoliose/complicações , Adolescente , Criança , Feminino , Seguimentos , Humanos , Cifose/complicações , Masculino , Dispositivos de Fixação Ortopédica , Radiografia , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Fusão Vertebral/métodos
19.
J Bone Joint Surg Br ; 73(2): 330-4, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2005167

RESUMO

We have prospectively compared the fixation of 100 intertrochanteric fractures of the proximal femur in elderly patients with random use of either a Dynamic Hip Screw (DHS) or a new intramedullary device, the Gamma nail. We found no difference in operating time, blood loss, wound complications, stay in hospital, place of eventual discharge, or the patients' mobility at final review. There was no difference in failure of proximal fixation: cut-out occurred in three cases with the DHS, and twice with the Gamma nail. However, in four cases fracture of the femur occurred close to the Gamma nail, requiring further major surgery. In the absence of these complications, union was seen by six months in both groups.


Assuntos
Parafusos Ósseos , Fixação Intramedular de Fraturas/instrumentação , Fraturas do Quadril/cirurgia , Idoso , Feminino , Fixação Intramedular de Fraturas/efeitos adversos , Fraturas do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Radiografia
20.
J Bone Joint Surg Br ; 65(2): 171-5, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6826624

RESUMO

The results of 63 operative repairs of chronic tears of the rotator cuff in 61 patients are reviewed retrospectively; the mean follow-up was 32.7 months. Fifty-four patients presented with symptoms of persistent pain and seven patients with gross loss of movement. All the patients had failed to respond to conservative treatment. Results were assessed in terms of relief of pain, restoration of movement, the patients' ability to return to work and whether they were satisfied with the results. Overall, a good result in terms of relief of pain was achieved in 40 shoulders. In 31 shoulders (30 with pain and one without pain) the operation included particular measures to decompress the subacromial space; 26 of the patients achieved relief of pain which was significantly better than in those patients whose operation did not include a decompression. The complications and failures are discussed. It is suggested that operative repair of the chronically torn rotator cuff of the shoulder is a worthwhile operation and that the operation should include an adequate decompression of the subacromial space.


Assuntos
Ligamentos Articulares/cirurgia , Articulação do Ombro/cirurgia , Adulto , Idoso , Doença Crônica , Feminino , Seguimentos , Humanos , Ligamentos Articulares/lesões , Masculino , Métodos , Pessoa de Meia-Idade , Movimento , Ruptura , Lesões do Ombro , Articulação do Ombro/fisiologia
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