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1.
Ann Oncol ; 34(2): 173-185, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36414192

RESUMO

BACKGROUND: First-line nivolumab plus ipilimumab prolongs survival versus chemotherapy in advanced non-small-cell lung cancer (NSCLC). We further characterized clinical benefit with this regimen in a large pooled patient population and assessed the effect of response on survival. PATIENTS AND METHODS: Data were pooled from four studies of first-line nivolumab plus ipilimumab in advanced NSCLC (CheckMate 227 Part 1, 817 cohort A, 568 Part 1, and 012). Overall survival (OS), progression-free survival (PFS), objective response rate, duration of response, and safety were assessed. Landmark analyses of OS by response status at 6 months and by tumor burden reduction in responders to nivolumab plus ipilimumab were also assessed. RESULTS: In the pooled population (N = 1332) with a minimum follow-up of 29.1-58.9 months, median OS was 18.6 months, with a 3-year OS rate of 35%; median PFS was 5.4 months (3-year PFS rate, 17%). Objective response rate was 36%; median duration of response was 23.7 months, with 38% of responders having an ongoing response at 3 years. In patients with tumor programmed death-ligand 1 (PD-L1) <1%, ≥1%, 1%-49%, or ≥50%, 3-year OS rates were 30%, 38%, 30%, and 48%. Three-year OS rates were 30% and 38% in patients with squamous or non-squamous histology. Efficacy outcomes in patients aged ≥75 years were similar to the overall pooled population (median OS, 20.1 months; 3-year OS rate, 34%). In the pooled population, responders to nivolumab plus ipilimumab at 6 months had longer post-landmark OS than those with stable or progressive disease; 3-year OS rates were 66%, 22%, and 14%, respectively. Greater depth of response was associated with prolonged survival; in patients with tumor burden reduction ≥80%, 50% to <80%, or 30% to <50%, 3-year OS rates were 85%, 72%, and 44%, respectively. No new safety signals were identified in the pooled population. CONCLUSION: Long-term survival benefit and durable response with nivolumab plus ipilimumab in this large patient population further support this first-line treatment option for advanced NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Nivolumabe/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Ipilimumab/efeitos adversos , Neoplasias Pulmonares/patologia , Intervalo Livre de Progressão , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
2.
Ann Oncol ; 29(4): 959-965, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29408986

RESUMO

Background: Long-term data with immune checkpoint inhibitors in non-small-cell lung cancer (NSCLC) are limited. Two phase III trials demonstrated improved overall survival (OS) and a favorable safety profile with the anti-programmed death-1 antibody nivolumab versus docetaxel in patients with previously treated advanced squamous (CheckMate 017) and nonsquamous (CheckMate 057) NSCLC. We report results from ≥3 years' follow-up, including subgroup analyses of patients with liver metastases, who historically have poorer prognosis among patients with NSCLC. Patients and methods: Patients were randomized 1 : 1 to nivolumab (3 mg/kg every 2 weeks) or docetaxel (75 mg/m2 every 3 weeks) until progression or discontinuation. The primary end point of each study was OS. Patients with baseline liver metastases were pooled across studies by treatment for subgroup analyses. Results: After 40.3 months' minimum follow-up in CheckMate 017 and 057, nivolumab continued to show an OS benefit versus docetaxel: estimated 3-year OS rates were 17% [95% confidence interval (CI), 14% to 21%] versus 8% (95% CI, 6% to 11%) in the pooled population with squamous or nonsquamous NSCLC. Nivolumab was generally well tolerated, with no new safety concerns identified. Of 854 randomized patients across both studies, 193 had baseline liver metastases. Nivolumab resulted in improved OS compared with docetaxel in patients with liver metastases (hazard ratio, 0.68; 95% CI, 0.50-0.91), consistent with findings from the overall pooled study population (hazard ratio, 0.70; 95% CI, 0.61-0.81). Rates of treatment-related hepatic adverse events (primarily grade 1-2 liver enzyme elevations) were slightly higher in nivolumab-treated patients with liver metastases (10%) than in the overall pooled population (6%). Conclusions: After 3 years' minimum follow-up, nivolumab continued to demonstrate an OS benefit versus docetaxel in patients with advanced NSCLC. Similarly, nivolumab demonstrated an OS benefit versus docetaxel in patients with liver metastases, and remained well tolerated. Clinical trial registration: CheckMate 017: NCT01642004; CheckMate 057: NCT01673867.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Docetaxel/uso terapêutico , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico , Idoso , Antineoplásicos/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/secundário , Docetaxel/efeitos adversos , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Nivolumabe/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Resultado do Tratamento
3.
ESMO Open ; 8(2): 101183, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36905787

RESUMO

BACKGROUND: For patients with stage IV non-small-cell lung cancer with epidermal growth factor receptor (EGFR) exon 19 deletions and exon 21 L858R mutations, osimertinib is the standard of care. Investigating the activity and safety of osimertinib in patients with EGFR exon 18 G719X, exon 20 S768I, or exon 21 L861Q mutations is of clinical interest. PATIENTS AND METHODS: Patients with stage IV non-small-cell lung cancer with confirmed EGFR exon 18 G719X, exon 20 S768I, or exon 21 L861Q mutations were eligible. Patients were required to have measurable disease, an Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate organ function. Patients were required to be EGFR tyrosine kinase inhibitor-naive. The primary objective was objective response rate, and secondary objectives were progression-free survival, safety, and overall survival. The study used a two-stage design with a plan to enroll 17 patients in the first stage, and the study was terminated after the first stage due to slow accrual. RESULTS: Between May 2018 and March 2020, 17 patients were enrolled and received study therapy. The median age of patients was 70 years (interquartile range 62-76), the majority were female (n = 11), had a performance status of 1 (n = 10), and five patients had brain metastases at baseline. The objective response rate was 47% [95% confidence interval (CI) 23% to 72%], and the radiographic responses observed were partial response (n = 8), stable disease (n = 8), and progressive disease (n = 1). The median progression-free survival was 10.5 months (95% CI 5.0-15.2 months), and the median OS was 13.8 months (95% CI 7.3-29.2 months). The median duration on treatment was 6.1 months (range 3.6-11.9 months), and the most common adverse events (regardless of attribution) were diarrhea, fatigue, anorexia, weight loss, and dyspnea. CONCLUSIONS: This trial suggests osimertinib has activity in patients with these uncommon EGFR mutations.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Masculino , Feminino , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Inibidores de Proteínas Quinases/efeitos adversos , Mutação , Receptores ErbB/genética , Éxons/genética
4.
Semin Radiat Oncol ; 9(2 Suppl 1): 58-63, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10210541

RESUMO

The beneficial effects of chemotherapy in patients with advanced head and neck cancer remain controversial in terms of survival, but have shown some promise in improving locoregional control and quality of life. In an effort to improve locoregional control and survival, a prospective phase II study was initiated using paclitaxel and carboplatin with concurrent conventional fractionated external-beam radiotherapy. Paclitaxel and carboplatin have both shown excellent radiosensitization through two discrete mechanisms, cell blockage in G2/M phase and inhibition of DNA repair, respectively. Patients were stratified as either operable or inoperable. This report pertains to the inoperable patient group, who received eight cycles of weekly paclitaxel (60 mg/m2), carboplatin (area under the concentration-time curve of 1) with conventional radiotherapy (72 Gy). Chemoradiotherapy was followed by neck dissection for those patients who presented with clinically palpable lymph nodes. Thirty-three patients were enrolled in this group (23 men and 10 women with a median age of 56 years). Eleven patients (33%) had stage III disease; 22 (67%), stage IV disease. The median follow-up period was 14 months. Clinical complete response occurred in 20 patients (60%) and partial response occurred in 10 (30%), for an overall response rate of 90%. Following completion of therapy, 18 patients have undergone biopsy at the primary tumor site and 17 were negative. Eight of the 16 patients with clinically palpable neck nodes at presentation underwent neck dissection; five (63%) had negative nodes. Mucositis was the most common toxicity. Grade 3 or 4 mucositis occurred in 30 of the 33 (90%) patients. Other grade 3 or 4 toxicities included skin (22%), candidiasis (19%), neutropenia (9%), and dehydration (6%). One patient with laryngeal carcinoma who had pathologic complete response developed cartilage necrosis and is undergoing hyperbaric oxygen therapy. Survival data are early but encouraging. Concurrent paclitaxel, carboplatin, and external-beam radiotherapy yielded excellent clinical and pathologic responses. Mucositis remains the most common and significant morbidity. The study will continue for necessary accrual.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Terapia Combinada , Intervalos de Confiança , Feminino , Humanos , Masculino , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Estudos Prospectivos , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
5.
Semin Radiat Oncol ; 9(2 Suppl 1): 77-84, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10210544

RESUMO

Preoperative chemotherapy and chemoradiation protocols are generally associated with high clinical response rates but limited pathologic responses for large primary tumors. We have initiated a prospective phase II study of weekly paclitaxel and carboplatin plus concurrent, fractionated external-beam radiation, followed by organ-preserving or function-restorative surgery (when applicable to maximize locoregional tumor control). Operable patients staged by triple endoscopy received a percutaneous gastrostomy and vigorous dental and nutritional support during therapy. Paclitaxel 60 mg/m2 and carboplatin at an area under the concentration-time curve of 1 were administered weekly with radiation therapy 45 Gy, with repeat biopsy of the primary site at 5 weeks. Patients with a positive biopsy had definitive surgery within 4 to 5 weeks. Patients with a negative biopsy received 3 additional weeks of radiation therapy, to a total dose of 72 Gy plus paclitaxel and carboplatin. Forty-three patients were enrolled, including 33 men and 10 women ranging in age from 37 to 81 years. Fourteen patients had stage III disease, 19 patients had stage IVA disease, and 10 patients had stage IVB disease. Sites of disease included the floor of the mouth (n = 8), tongue (n = 8), oropharynx (n = 5), hypopharynx (n = 4), larynx (n = 12), palate-tonsil (n = 2), unknown primary (n = 3), and nasal cavity (n = 1). Of 38 patients evaluable for primary response (two patients had unknown primary tumor, two patients failed to complete the chemoradiation protocol, and one patient was evaluable for toxicity only), 18 patients had a complete clinical response and 20 patients had a partial response; the overall clinical response rate was 100%. A pathologic clinical response at the primary site occurred in 25 of these 38 patients (66%), who subsequently received completion radiation (67 to 72 Gy). After induction chemoradiation, 36 patients with N1-N3 nodes had neck dissection; seven had positive nodes (19%). Fourteen patients had residual cancer at the primary site at the time of the repeat biopsy. Sites of the lesions were the floor of the mouth/mandible (n = 4), nasal cavity/maxilla (n = 2), base of tongue (n = 2), and larynx (n = 6). All were resected with function-preserving reconstruction (two patients required total laryngectomy and one patient refused surgery). At a median follow-up of more than 16 months, progression-free and overall survival rates were 64% and 68%, respectively. Preoperative paclitaxel, carboplatin, and radiation was associated with a high clinical response rate at the primary site and a high level of organ preservation or functional restoration, if ablation was performed.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , Estudos Prospectivos , Análise de Sobrevida , Resultado do Tratamento
6.
Semin Oncol ; 24(6 Suppl 19): S19-57-S19-61, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9427268

RESUMO

Radiotherapy or surgery alone for advanced head and neck cancer generally yields poor results. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and carboplatin have both shown excellent radiosensitization through two discrete mechanisms, namely, blocking the cell cycle in the G2/M phase and inhibiting DNA repair. In an effort to improve locoregional control and survival, a prospective phase II study was initiated using paclitaxel 60 mg/ml and carboplatin (area under the concentration-time curve of 1), each given as a single dose weekly with concurrent conventional fractionated external beam radiotherapy. Patients were stratified into two groups: operable and inoperable/unresectable. The operable and inoperable groups received 5 weeks (45 Gy) and 8 weeks (72 Gy) of chemoradiotherapy, respectively. Patients in the operable group were evaluated with repeat biopsies from the primary site after 5 weeks. Those with a positive biopsy underwent surgery; those with a negative biopsy received 3 additional weeks of chemoradiotherapy. Thirty-four patients were entered in the operable group (28 men and six women; 40 to 71 years of age; 12 stage III and 22 stage IV). Of 26 evaluable patients, 19 (73%) had a complete clinical response (95% confidence interval [CI], 52% to 88%) and six (23%) had a partial response (95% CI, 9% to 44%), for a total clinical response rate of 96% (95% CI, 80% to 100%). A pathologic complete response at the primary site (two had an unknown primary site) occurred in 17 of 24 (71%) patients (95% CI, 49% to 87%). Of 20 patients with N1-3 nodes who underwent neck dissection, 17 (85%) had pathologically negative lymph nodes. Seven patients with residual tumor at the primary site were resected (oral cavity, three; maxilla, one; base of tongue, one; and larynx, two). Grades 3 and 4 mucositis were seen in 19 (73%) patients; mucositis was the most common and significant morbidity. Accrual for the inoperable group continues. Concomitant paclitaxel, carboplatin, and external beam radiotherapy yielded excellent clinical responses, but produced significant grade 3/4 toxicity. In the operable group, the majority of responders had a complete pathologic response. These preliminary findings will be assessed in terms of response duration, organ preservation, and long-term survival.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Paclitaxel/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Carboplatina/toxicidade , Carcinoma de Células Escamosas/mortalidade , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/toxicidade , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento
7.
Am J Surg ; 174(5): 518-22, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9374228

RESUMO

BACKGROUND: Preoperative chemotherapy or chemoradiation protocols are generally associated with high clinical response rates, but limited pathologic responses for large primary tumors. We have initiated a prospective phase II study of weekly paclitaxel 60 mg/M2, and carboplatin (AUC of 1) plus concurrent fractionated external beam radiation (45 Gy) followed by organ-preserving (or function restorative) surgery when applicable to maximize local-regional tumor control. PATIENTS AND METHODS: Operable patients staged by triple endoscopy received a percutaneous endoscopic gastrostomy and vigorous dental and nutritional support during therapy. Weekly paclitaxel 60 mg/M2, carboplatin (AUC of 1), and radiation 45 Gy were given with rebiopsy of the primary site at 5 weeks. Patients with positive biopsy had definitive surgery in 4 to 5 weeks. Patients with negative biopsy-results received 3 additional weeks of radiation, to a total dose of 72 Gy plus carboplatin and paclitaxel. RESULTS: The 35 patients were 29 men and 6 women, aged 40 to 71 years, with stage III (12) or stage IV (23) cancer. The site of the cancer was oral cavity, 10; base of tongue, 3; oropharynx, 3; hypopharynx, 4; larynx, 12 (glottic, 6; supraglottic, 6), unknown primary, 2; other, nasal cavity, 1. Of 34 evaluable patients, 16 (47%) had a complete clinical response (CR) and 18 (53%) had a partial response (PR); total clinical response rate was 100%. A pathologic CR at the primary site occurred in 23 of 34 patients (68%; 2 had an unknown primary) who went on to completion radiation at 67 to 72 Gy. After induction chemoradiation 21 patients with N1-3 nodes had neck dissection; 6 (31%) had positive nodes. Twelve patients had residual cancer at the primary site at time of rebiopsy: mandible, 4; maxilla, 1; base of tongue, 2; larynx, 4; floor of mouth, 1; and nasal cavity, 1. All were resected with function-preserving reconstruction. At median follow-up of >12 months, progression-free and overall survivals were 71% and 83%, respectively. CONCLUSION: Preoperative treatment with paclitaxel, carboplatin, and radiation is associated with high CR at the primary site and a high level of organ preservation or functional restoration if ablation is done.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Carboplatina/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Cuidados Pré-Operatórios , Estudos Prospectivos , Radiossensibilizantes/administração & dosagem , Dosagem Radioterapêutica , Taxa de Sobrevida
8.
Lepr Rev ; 72(2): 199-205, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11495451

RESUMO

Cohort-based multidrug therapy (MDT) completion rates are used to assess adherence to MDT. However this measure gives no information about when during the treatment period defaulting occurs. Two districts in Cabo Delgado province in Northern Mozambique were selected for evaluation of multibacillary patient defaulter data between 1993 and 1997 to examine when patients default during the treatment penod. In all, 548 (59.2%) of 926 MB patients completed treatment and 378 (40.8%) defaulted between 1993 to 1997. The percentage of defaulters fell steadily from 59.8% in 1993 to 23.2% in 1997. Of the 378 defaulters 57.7% defaulted treatment within 6 months and 83.1% within 1 year of starting treatment. It was observed that patients tend to default early rather than late in the treatment period and that this pattern is maintained over time despite a fall in defaulter rates. Patients established early into a treatment routine were more likely to complete treatment. A comprehensive effort to improve and maintain leprosy control services will probably influence adherence more than any single, specific strategy. Shortening MDT treatment from 2 years to 1 year is unlikely to affect the defaulter rate.


Assuntos
Hansenostáticos/uso terapêutico , Hanseníase/tratamento farmacológico , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Humanos , Hanseníase/epidemiologia , Hanseníase/prevenção & controle , Moçambique/epidemiologia , Polimedicação , Prevalência , Sistema de Registros
9.
Technol Cancer Res Treat ; 11(3): 221-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22468993

RESUMO

Involvement of a cranial nerve caries a poor prognosis for many malignancies. Recurrent or residual disease in the trigeminal or facial nerve after primary therapy poses a challenge due to the location of the nerve in the skull base, the proximity to the brain, brainstem, cavernous sinus, and optic apparatus and the resulting complex geometry. Surgical resection caries a high risk of morbidity and is often not an option for these patients. Stereotactic radiosurgery and radiotherapy are potential treatment options for patients with cancer involving the trigeminal or facial nerve. These techniques can deliver high doses of radiation to complex volumes while sparing adjacent critical structures. In the current study, seven cases of cancer involving the trigeminal or facial nerve are presented. These patients had unresectable recurrent or residual disease after definitive local therapy. Each patient was treated with stereotactic radiation therapy using a linear accelerator based system. A multidisciplinary approach including neuroradiology and surgical oncology was used to delineate target volumes. Treatment was well tolerated with no acute grade 3 or higher toxicity. One patient who was reirradiated experienced cerebral radionecrosis with mild symptoms. Four of the seven patients treated had no evidence of disease after a median follow up of 12 months (range 2-24 months). A dosimetric analysis was performed to compare intensity modulated fractionated stereotactic radiation therapy (IM-FSRT) to a 3D conformal technique. The dose to 90% (D90) of the brainstem was lower with the IM-FSRT plan by a mean of 13.5 Gy. The D95 to the ipsilateral optic nerve was also reduced with IM-FSRT by 12.2 Gy and the D95 for the optic chiasm was lower with FSRT by 16.3 Gy. Treatment of malignancies involving a cranial nerve requires a multidisciplinary approach. Use of an IM-FSRT technique with a micro-multileaf collimator resulted in a lower dose to the brainstem, optic nerves and chiasm for each case examined.


Assuntos
Neoplasias dos Nervos Cranianos/radioterapia , Fracionamento da Dose de Radiação , Nervo Facial , Radiocirurgia/métodos , Nervo Trigêmeo , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Nervos Cranianos/patologia , Nervo Facial/patologia , Nervo Facial/efeitos da radiação , Seguimentos , Cabeça/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Radioterapia de Intensidade Modulada/métodos , Indução de Remissão , Medição de Risco , Nervo Trigêmeo/patologia , Nervo Trigêmeo/efeitos da radiação
12.
J Exp Zool ; 238(1): 43-54, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3711818

RESUMO

In males of the katydid Neoconocephalus robustus, mesothoracic wings are used in flight (wing stroke frequence = 20 Hz) and stridulation (200 Hz), while the metathoracic wings are used in flight alone. Most mesothoracic wing muscles produce much briefer isometric twitches than metathoracic counterparts. The mesothoracic first tergocoxal muscle (TCX1) has a twitch duration (onset to 50% relaxation, 35 degrees C) of 6-8 ms and the metathoracic TXC1 a twitch duration of 12-15 ms. The TCX1 muscles from animals one and two instars from adulthood produce twitches similar in duration to those of the adult metathoracic TCX1. The twitch duration of the mesothoracic TCX1 acquires its adult brevity gradually over the first 5 days of adult life. Both TCX1 muscles increase greatly in size and mitochondrial content around the time of the terminal molt. During this period the mesothoracic TCX1 develops narrower myofibrils and a smaller ratio of fibril volume to sarcoplasmic reticulum volume than is characteristic of the metathoracic TCX1. Changes in the ultrastructure of the mesothoracic TCX1 precede changes in contraction kinetics around the time of the terminal molt so that there is not a strict correlation between muscle structure and performance during the period of rapid growth.


Assuntos
Ortópteros/crescimento & desenvolvimento , Animais , Voo Animal , Cinética , Microscopia Eletrônica , Contração Muscular , Desenvolvimento Muscular , Músculos/fisiologia , Músculos/ultraestrutura , Vocalização Animal , Asas de Animais/crescimento & desenvolvimento
13.
J Exp Zool ; 233(1): 35-50, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3973549

RESUMO

The sizes of the unifunctional dorsal longitudinal (DLM) and bifunctional subalar (SA) metathoracic flight muscles of the cricket Teleogryllus oceanicus increase by more than an order of magnitude between the second instar before the terminal molt and the tenth day of adult life. During the same developmental period isometric twitch duration (onset to 50% relaxation, 25 degrees C) varies little, while muscle mitochondrial content increased by a factor of ten as measured by stereological analysis of electron micrographs and citrate synthase activity (mumoles citrate . min-1 . gm protein-1, 25 degrees C). The wing muscles of adults have abundant sarcoplasmic reticulum (SR), narrow myofibrils, and a high volume density of mitochondria. At two molts from adulthood muscles that will later be used in flight behavior also have narrow myofibrils and abundant SR, but unlike muscles at later stages, nymphal muscles have a low volume density of mitochondria. At the terminal molt muscles have at least as much SR as is seen in muscles at the tenth day of adult life, and the myofibrils are also more narrow at the earlier stage. Since there is significant variation in muscle structure and little change in twitch duration during late development, the efficacy of the SR in releasing and resequestering CA2+ is seemingly lower in muscles at the terminal molt, a time of rapid muscle growth.


Assuntos
Músculos/ultraestrutura , Ortópteros/anatomia & histologia , Asas de Animais/anatomia & histologia , Animais , Citrato (si)-Sintase/metabolismo , Feminino , Masculino , Metamorfose Biológica , Microscopia Eletrônica , Mitocôndrias Musculares/ultraestrutura , Desenvolvimento Muscular , Músculos/fisiologia , Ortópteros/crescimento & desenvolvimento , Ortópteros/fisiologia , Asas de Animais/crescimento & desenvolvimento , Asas de Animais/fisiologia
14.
Proc Natl Acad Sci U S A ; 91(19): 8767-71, 1994 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-7522321

RESUMO

P-selectin on activated platelets and stimulated endothelial cells mediates cell adhesion with monocytes and neutrophils. Since activated platelets induce tissue factor on mononuclear leukocytes, we examined the effect of P-selectin on the expression of tissue factor activity in monocytes. Purified P-selectin stimulated tissue factor expression on mononuclear leukocytes in a dose-dependent manner. Chinese hamster ovary (CHO) cells expressing P-selectin stimulated tissue factor procoagulant activity in purified monocytes, whereas untransfected CHO cells and CHO cells expressing E-selectin did not. Anti-P-selectin antibodies inhibited the effects of purified P-selectin and CHO cells expressing P-selectin on monocytes. Incubation of CHO cells expressing P-selectin with monocytes leads to the development of tissue factor mRNA in monocytes and to the expression of tissue factor antigen on the monocyte surface. These results indicate that P-selectin upregulates the expression of tissue factor on monocytes as well as mediates the binding of platelets and endothelial cells with monocytes and neutrophils. The binding of P-selectin to monocytes in the area of vascular injury may be a component of a mechanism that initiates thrombosis.


Assuntos
Monócitos/metabolismo , Glicoproteínas da Membrana de Plaquetas/farmacologia , Tromboplastina/metabolismo , Moléculas de Adesão Celular/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas In Vitro , Selectina-P , RNA Mensageiro/genética , Tromboplastina/genética
15.
Ann Surg Oncol ; 8(8): 644-50, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11569779

RESUMO

BACKGROUND: The role of surgery in aggressive chemoradiation protocols for advanced head and neck cancer has been questioned because of the quoted high clinical response rates in many series. METHODS: The role of surgical resection was examined in an aggressive neoadjuvant protocol of weekly paclitaxel, carboplatin, and radiation for stage III and IV with completion of radiation to 72 Gy if biopsy at the primary site was negative after administration of 45 Gy. Of 43 patients enrolled, 38 completed the protocol. The clinical response was 100% (including 18 complete and 20 partial responses). RESULTS: The complete pathologic response (negative primary site biopsy at 45 Gy) was 25 of 38 (66%). Of patients who presented with N1 to N3 nodes, neck dissection revealed residual nodal metastases in 22%. Surgical resection of the primary site was required in 13 patients, including 5 with larynx cancer and 2 with base of tongue cancers. Four patients had resection with reconstruction for advanced mandible floor of mouth cancer, and one had resection of nasal-maxillary cancer. Functional resection was performed in 9 of 12 patients. The median progression free and overall survival was 64% and 68%, respectively, at median follow-up of 50 months. Nine patients developed recurrence (three local and six distant). There were no failures in the neck. Salvage surgery was performed in one patient with local and one with distant disease. CONCLUSIONS: Surgical resection is an essential component of aggressive chemoradiation protocols to ensure tumor control at the primary site and in the neck.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Radioterapia Adjuvante , Adulto , Idoso , Idoso de 80 Anos ou mais , Carboplatina/administração & dosagem , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/terapia , Quimioterapia Adjuvante , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Recuperação de Função Fisiológica , Índice de Gravidade de Doença , Taxa de Sobrevida , Resultado do Tratamento
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