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1.
Ann Surg ; 278(3): 396-407, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37314222

RESUMO

OBJECTIVE: To characterize industry nonresearch payments made to general and fellowship-trained surgeons between 2016 and 2020. BACKGROUND: The Centers for Medicare & Medicaid Services Open Payments Data (OPD) reports industry payments made to physicians related to drugs and medical devices. General payments are those not associated with research. METHODS: OPD data were queried for general and fellowship-trained surgeons who received general payments from 2016 to 2020. Payments' nature, amount, company, covered product, and location were collected. Surgeons' demographics, subspecialty, and leadership roles in hospitals, societies, and editorial boards were evaluated. RESULTS: From 2016 to 2020, 44,700 general and fellowship-trained surgeons were paid $535,425,543 in 1,440,850 general payments. The median payment was $29.18. The most frequent payments were for food and beverage (76.6%) and travel and lodging (15.6%); however, the highest dollar payments were for consulting fees ($93,128,401; 17.4%), education ($88,404,531; 16.5%), royalty or license ($87,471,238; 16.3%), and travel and lodging ($66,333,149; 12.4%). Five companies made half of all payments ($265,654,522; 49.6%): Intuitive Surgical ($128,517,411; 24%), Boston Scientific ($48,094,570; 9%), Edwards Lifesciences ($41,835,544, 7.8%), Medtronic Vascular ($33,607,136; 6.3%), and W. L. Gore & Associates ($16,626,371; 3.1%). Medical devices comprised 74.7% of payments ($399,897,217), followed by drugs and biologicals ($33,945,300; 6.3%). Texas, California, Florida, New York, and Pennsylvania received the most payments; however, the top dollar payments were in California ($65,702,579; 12.3%), Michigan ($52,990,904, 9.9%), Texas ($39,362,131; 7.4%), Maryland ($37,611,959; 7%), and Florida ($33,417,093, 6.2%). General surgery received the highest total payments ($245,031,174; 45.8%), followed by thoracic surgery ($167,806,514; 31.3%) and vascular surgery ($60,781,266; 11.4%). A total of 10,361 surgeons were paid >$5000, of which 1614 were women (15.6%); in this group, men received higher payments than women (means, $53,446 vs $22,571; P <0.001) and thoracic surgeons received highest payments (mean, $76,381; NS, P =0.14). A total of 120 surgeons were paid >$500,000 ($203,011,672; 38%)-5 non-Hispanic White (NHW) women (4.2%) and 82 NHW (68.3%), 24 Asian (20%), 7 Hispanic (5.8%), and 2 Black (1.7%) men; in this group, men received higher payments than women (means, $1,735,570 vs $684,224), and NHW men received payments double those of other men (means, $2,049,554 vs $955,368; NS, P =0.087). Among these 120 highly paid surgeons (>$500,000), 55 held hospital and departmental leadership roles, 30 were leaders in surgical societies, 27 authored clinical guidelines, and 16 served on journal editorial boards. During COVID-19, 2020 experienced half the number of payments than the preceding 3 years. CONCLUSIONS: General and fellowship-trained surgeons received substantial industry nonresearch payments. The highest-paid recipients were men. Further work is warranted in assessing how race, gender, and leadership roles influence the nature of industry payments and surgical practice. A significant decline in payments was observed early during the COVID-19 pandemic.


Assuntos
COVID-19 , Cirurgiões , Idoso , Masculino , Humanos , Feminino , Estados Unidos , Bolsas de Estudo , Pandemias , COVID-19/epidemiologia , Medicare , Conflito de Interesses , Bases de Dados Factuais
2.
J Surg Res ; 288: 188-192, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37018895

RESUMO

Academic surgery has changed along with the rest of the world in response to the COVID pandemic. With increasing rates of vaccination against COVID over the past 2 y, we have slowly but steadily made progress toward controlling the spread of the virus. Surgeons, academic surgery departments, health systems, and trainees are all attempting to establish a new normal in various domains-clinical, research, teaching, and in their personal lives. How has the pandemic changed these areas? At the 2022 Academic Surgical Congress Hot Topics session, we attempted to address these issues.


Assuntos
COVID-19 , Cirurgiões , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Departamentos Hospitalares
3.
J Surg Oncol ; 127(7): 1187-1195, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36938777

RESUMO

BACKGROUND AND OBJECTIVES: Melanoma mutational burden is high and approximately 50% have oncogenic mutations in BRAF. We sought to evaluate age-related mutational differences in melanoma. METHODS: We analyzed melanoma samples in the Genomics Evidence Neoplasia Information Exchange database. Targetable mutations were identified using the Precision Oncology Knowledge Base (OncoKB). RESULTS: We found 1194 patients with a common set of 30 genes. The top mutated genes in patients <40 years old (y/o) (n = 98) were BRAF (59%), TP53 (31%), NRAS (17%), and PTEN (14%); in 40-59 y/o (n = 354) were BRAF (51%), NRAS (30%), TP53 (26%), and APC (13%); and in ≥60 y/o (n = 742) were BRAF (38%), NRAS (33%), TP53 (26%), and KDR (19%). BRAF mutations were almost mutually exclusive from NRAS mutations in <40 y/o (58/59). Mutational burden increased with age, with means of 2.39, 2.92, and 3.67 mutations per sample in patients <40, 40-59, and ≥60 y/o, respectively (p < 0.0001). There were 10 targetable mutations meeting OncoKB criteria for melanoma: BRAF (level 1), RET (level 1), KIT (level 2), NRAS (level 3A), TP53 (level 3A), and FGFR2, MET, PTEN, PIK3CA, and KRAS (level 4). CONCLUSIONS: Mutations in melanoma have age-related differences and demonstrates potential targetable mutations for personalized therapies.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Adulto , Proteínas Proto-Oncogênicas B-raf/genética , Medicina de Precisão , Melanoma/genética , Mutação , Sequenciamento de Nucleotídeos em Larga Escala , Análise Mutacional de DNA , Neoplasias Cutâneas/genética
4.
Curr Oncol Rep ; 24(11): 1425-1432, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35657482

RESUMO

PURPOSE OF REVIEW: To review and update surgeons about the evolving complexities in the surgical management of melanoma including lymph node staging and treatment. RECENT FINDINGS: Primary resection with adequate margins continues to be the standard of care for localized cutaneous melanoma. Sentinel lymph node biopsy is confirmed to be a powerful tool due to its prognostic value and informative guidance for adjuvant treatments and surveillance. Due to the lack of benefit in melanoma-specific survival and distant metastasis-free survival, completion lymph node dissection is not performed routinely after a positive sentinel lymph node biopsy. Neoadjuvant systemic treatment approaches for advanced loco-regional disease show promise in phase I and II clinical trial data, and phase III studies. The surgical management of cutaneous melanoma continues to evolve with further de-escalation of the extent of excision of primary melanomas and the management of lymph node disease.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/patologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Metástase Linfática , Biópsia de Linfonodo Sentinela , Excisão de Linfonodo , Linfonodos/patologia , Estadiamento de Neoplasias
7.
Clin Cancer Res ; 23(3): 649-657, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27301700

RESUMO

PURPOSE: Recent studies demonstrate that addition of neoadjuvant (NA) carboplatin to anthracycline/taxane chemotherapy improves pathologic complete response (pCR) in triple-negative breast cancer (TNBC). Effectiveness of anthracycline-free platinum combinations in TNBC is not well known. Here, we report efficacy of NA carboplatin + docetaxel (CbD) in TNBC. EXPERIMENTAL DESIGN: The study population includes 190 patients with stage I-III TNBC treated uniformly on two independent prospective cohorts. All patients were prescribed NA chemotherapy regimen of carboplatin (AUC 6) + docetaxel (75 mg/m2) given every 21 days × 6 cycles. pCR (no evidence of invasive tumor in the breast and axilla) and residual cancer burden (RCB) were evaluated. RESULTS: Among 190 patients, median tumor size was 35 mm, 52% were lymph node positive, and 16% had germline BRCA1/2 mutation. The overall pCR and RCB 0 + 1 rates were 55% and 68%, respectively. pCRs in patients with BRCA-associated and wild-type TNBC were 59% and 56%, respectively (P = 0.83). On multivariable analysis, stage III disease was the only factor associated with a lower likelihood of achieving a pCR. Twenty-one percent and 7% of patients, respectively, experienced at least one grade 3 or 4 adverse event. CONCLUSIONS: The CbD regimen was well tolerated and yielded high pCR rates in both BRCA-associated and wild-type TNBC. These results are comparable with pCR achieved with the addition of carboplatin to anthracycline-taxane chemotherapy. Our study adds to the existing data on the efficacy of platinum agents in TNBC and supports further exploration of the CbD regimen in randomized studies. Clin Cancer Res; 23(3); 649-57. ©2016 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Carboplatina/efeitos adversos , Carcinoma/genética , Carcinoma/terapia , Estudos de Casos e Controles , Terapia Combinada , Docetaxel , Feminino , Filgrastim/uso terapêutico , Genes BRCA1 , Genes BRCA2 , Humanos , Kansas , Mastectomia , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Polietilenoglicóis/uso terapêutico , Estudos Prospectivos , Espanha , Taxoides/administração & dosagem , Taxoides/efeitos adversos , Resultado do Tratamento , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/terapia
8.
J Surg Oncol ; 111(2): 198-202, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25266871

RESUMO

BACKGROUND: We evaluated the impact of Neoadjuvant Chemotherapy (NAC) versus primary surgery (PS) on axillary disease burden/surgery in clinically node negative Triple Negative Breast Cancer (TNBC). METHODS: Two hundred forty-three Stage I-III TNBC patients have enrolled on an IRB approved multisite prospective registry. Clinical and treatment information was collected. RESULTS: One hundred fifty-five patients with clinically node negative TNBC were identified. 47%, 49%, and 4% of patients had T1, T2, and T3 disease, respectively. Patients underwent PS (103/155, 66%) or NAC (52/155, 34%) at the discretion of treating physicians. 17% of PS and 0% of NAC patients were node positive at surgery (P=0.006). For T2 disease, 32% of PS and 0% of NAC patients were node positive at surgery (P=0.001). NAC patients had a lower chance of positive SLNB (0% vs. 12%, P=0.004) and undergoing ALND (2% vs. 22%, P=0.001) than PS patients. CONCLUSION: In this clinically node negative TNBC cohort, all NAC-treated patients were node negative at surgery, whereas 17% of PS patients had involved axillary nodes. NAC should be considered for clinically node negative TNBC to reduce the extent of axillary surgery even if breast conservation is not planned.


Assuntos
Terapia Neoadjuvante , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Excisão de Linfonodo , Metástase Linfática , Mastectomia , Mastectomia Segmentar , Pessoa de Meia-Idade , Sistema de Registros , Biópsia de Linfonodo Sentinela
9.
Mol Carcinog ; 54(12): 1710-21, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25491779

RESUMO

Melanoma is an aggressive disease with limited therapeutic options. Here, we determined the effects of honokiol (HNK), a biphenolic natural compound on melanoma cells and stemness. HNK significantly inhibited melanoma cell proliferation, viability, clonogenicity and induced autophagy. In addition, HNK significantly inhibited melanosphere formation in a dose dependent manner. Western blot analyses also demonstrated reduction in stem cell markers CD271, CD166, Jarid1b, and ABCB5. We next examined the effect of HNK on Notch signaling, a pathway involved in stem cell self-renewal. Four different Notch receptors exist in cells, which when cleaved by a series of enzymatic reactions catalyzed by Tumor Necrosis Factor-α-Converting Enzyme (TACE) and γ-secretase protein complex, results in the release of the Notch intracellular domain (NICD), which then translocates to the nucleus and induces target gene expression. Western blot analyses demonstrated that in HNK treated cells there is a significant reduction in the expression of cleaved Notch-2. In addition, there was a reduction in the expression of downstream target proteins, Hes-1 and cyclin D1. Moreover, HNK treatment suppressed the expression of TACE and γ-secretase complex proteins in melanoma cells. To confirm that suppression of Notch-2 activation is critical for HNK activity, we overexpressed NICD1, NICD2, and performed HNK treatment. NICD2, but not NICD1, partially restored the expression of Hes-1 and cyclin D1, and increased melanosphere formation. Taken together, these data suggest that HNK is a potent inhibitor of melanoma cells, in part, through the targeting of melanoma stem cells by suppressing Notch-2 signaling.


Assuntos
Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Receptor Notch2/metabolismo , Proteínas ADAM/metabolismo , Proteína ADAM17 , Secretases da Proteína Precursora do Amiloide/metabolismo , Autofagia/efeitos dos fármacos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição HES-1
10.
Am J Surg ; 208(6): 995-1002; discussion 1001-2, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25450590

RESUMO

BACKGROUND: Malignant melanoma is an aggressive form of skin cancer with limited effective therapeutic options. Melanoma research concentrates on maximizing the effect on cancer cells with minimal toxicity to normal cells. AMP-activated protein kinase (AMPK) is an important regulator of cellular energy homeostasis and has been shown to control tumor progression regulating the cell cycle, protein synthesis, and cell growth and/or survival. Honokiol (HNK) is a biphenolic compound derived from Magnolia officinalis, a plant that has been used in traditional Chinese and Japanese medicine for the treatment of various pathological conditions. Recent studies have shown that HNK has antitumor activity with relatively low toxicity. In this study, we demonstrated that the growth inhibitory effects of HNK on melanoma and melanoma cancer stem cells were mediated through the activation of AMPK and hence AMPK signaling in melanoma cells. METHODS: We determined the effects of HNK treatment on various melanoma cell lines. HNK-induced cell growth inhibitory effects were determined using hexosaminidase assay. Protein expression studies were done by immunoblotting. Primary spheroid assay was used to assess stemness by growing single suspension cells in ultralow attachment plates. RESULTS: HNK is highly effective in inhibiting melanoma cells by attenuating protein kinase B/mammalian target of rapamycin and AMPK signaling. HNK showed significant inhibition of the spheroid-forming capacity of melanoma cells and, hence, stemness. HNK significantly decreased the number and size of melanospheres in a dose-dependent manner. Western blot analyses showed enhanced phosphorylation of AMPK in melanoma cells. Furthermore, HNK decreased the cellular adenosine triphosphate pool in a dose-dependent manner with maximum effects observed at 48 hours. CONCLUSIONS: The results suggest that HNK can target melanoma cells and mark them for cell death through AMPK signaling. Further studies are warranted for developing HNK as an effective chemopreventive/therapeutic agent in melanoma.


Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Antineoplásicos Fitogênicos/farmacologia , Compostos de Bifenilo/farmacologia , Lignanas/farmacologia , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Immunoblotting , Melanoma/enzimologia , Microscopia Eletrônica de Varredura , Transdução de Sinais/efeitos dos fármacos , Neoplasias Cutâneas/enzimologia
11.
Am J Surg ; 204(6): 868-73, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23231930

RESUMO

BACKGROUND: Melanomas are aggressive neoplasms with limited therapeutic options. Therefore, developing new therapies with low toxicity is of utmost importance. Honokiol is a natural compound that recently has shown promise as an effective anticancer agent. METHODS: The effect of honokiol on melanoma cancer cells was assessed in vitro. Proliferation and physiologic changes were determined using hexosaminidase assay and transmission electron microscopy. Protein expression was assessed by immunoblotting. RESULTS: Honokiol treatment inhibited cell proliferation and induced death. Electron microscopy showed autophagosome formation. Reduced levels of cyclin D1 accompanied cell-cycle arrest. Honokiol also decreased phosphorylation of AKT (known as protein kinase B) and mammalian target of rapamycin, and inhibited γ-secretase activity by down-regulating the expression of γ-secretase complex proteins, especially anterior pharynx-defective 1. CONCLUSIONS: Honokiol is highly effective in inhibiting melanoma cancer cells by attenuating AKT/mammalian target of rapamycin and Notch signaling. These studies warrant further clinical evaluation for honokiol alone or with present chemotherapeutic regimens for the treatment of melanomas.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Lignanas/farmacologia , Melanoma/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Biomarcadores Tumorais/metabolismo , Compostos de Bifenilo/uso terapêutico , Pontos de Checagem do Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo , Immunoblotting , Lignanas/uso terapêutico , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo
12.
Am J Surg ; 204(6): 981-6; discussion 986-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23231937

RESUMO

BACKGROUND: Skin and breast cancers are the 2 most common malignancies in US women. Early detection with appropriate therapy is essential in improving survival rates. The aim of this study was to evaluate and compare general surgery (GS) and family medicine (FM) residents in their ability to identify and appropriately treat common skin and breast lesions. METHODS: Thirty-three-question, institutional review board-approved, Web-based surveys (1 breast and 1 skin survey) were each sent to 244 GS and 452 FM training programs (both university-based and community-based programs) uniformly distributed across the United States. Each survey included demographics and 20 multiple-choice questions (10 lesion identification questions and 10 corresponding treatment questions). RESULTS: A total of 374 completed resident surveys were collected (242 FM, 132 GS). Respondents were uniformly distributed geographically (55.9% women, 44.1% men; 54.2% community based, 45.8% university based). GS residents correctly identified 82.7% of lesions compared with 83.3% for FM residents (P = .89) and correctly treated 76.8% of lesions compared with 75.4% for FM residents (P = .81). No significant identification or treatment differences were noted by postgraduate year (PGY), but both GS and FM residents had lower accuracy of correct treatment identification compared with lesion identification, which was significant for GS PGY 2 residents (P = .02), FM PGY 2 residents (P = .03), and FM PGY 2 residents (P = .03). University-based GS residents had a more significant disparity between correct identification and correct treatment (83.6% vs 74.6%, P = .03) compared with community-based GS residents (80.4% vs 74.6%, P = .11). Both university-based and community-based FM residents had significant disparities in this comparison (university-based FM residents with 82.4% vs 69.8%, P = .02, vs community-based FM residents with 86.7% vs 74.5%, P = .04). CONCLUSIONS: Both GS and FM residents incorrectly treated more lesions than they diagnosed. This diagnosis-treatment disparity was more pronounced among university-based residents. Validation of this observation may better identify potential training deficiencies in breast and skin oncology to enhance GS resident education.


Assuntos
Neoplasias da Mama , Competência Clínica/estatística & dados numéricos , Medicina de Família e Comunidade/educação , Cirurgia Geral/educação , Internato e Residência/normas , Neoplasias Cutâneas , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Feminino , Hospitais Comunitários , Hospitais Universitários , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Inquéritos e Questionários , Estados Unidos
13.
Mol Cancer Ther ; 11(4): 963-72, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22319203

RESUMO

Cancer stem cells are implicated in resistance to ionizing radiation (IR) and chemotherapy. Honokiol, a biphenolic compound has been used in traditional Chinese medicine for treating various ailments. In this study, we determined the ability of honokiol to enhance the sensitivity of colon cancer stem cells to IR. The combination of honokiol and IR suppressed proliferation and colony formation while inducing apoptosis of colon cancer cells in culture. There were also reduced numbers and size of spheroids, which was coupled with reduced expression of cancer stem cell marker protein DCLK1. Flow cytometry studies confirmed that the honokiol-IR combination reduced the number of DCLK1+ cells. In addition, there were reduced levels of activated Notch-1, its ligand Jagged-1, and the downstream target gene Hes-1. Furthermore, expression of components of the Notch-1 activating γ-secretase complex, presenilin 1, nicastrin, Pen2, and APH-1 was also suppressed. On the other hand, the honokiol effects were mitigated when the Notch intracellular domain was expressed. To determine the effect of honokiol-IR combination on tumor growth in vivo, nude mice tumor xenografts were administered honokiol intraperitoneally and exposed to IR. The honokiol-IR combination significantly inhibited tumor xenograft growth. In addition, there were reduced levels of DCLK1 and the Notch signaling-related proteins in the xenograft tissues. Together, these data suggest that honokiol is a potent inhibitor of colon cancer growth that targets the stem cells by inhibiting the γ-secretase complex and the Notch signaling pathway. These studies warrant further clinical evaluation for the combination of honokiol and IR for treating colon cancers.


Assuntos
Compostos de Bifenilo/farmacologia , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/radioterapia , Medicamentos de Ervas Chinesas/farmacologia , Lignanas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Terapia Combinada , Regulação para Baixo , Células HCT116 , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/efeitos da radiação , Óxido Nítrico Sintase/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
15.
J Surg Educ ; 64(6): 386-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18063274

RESUMO

PURPOSE: Understanding the learning styles of individuals may assist in the tailoring of an educational program to optimize learning. General surgery faculty and residents have been characterized previously as having a tendency toward particular learning styles. We seek to understand better the learning styles of general surgery residents and differences that may exist within the population. METHODS: The Kolb Learning Style Inventory was administered yearly to general surgery residents at the University of Cincinnati from 1994 to 2006. This tool allows characterization of learning styles into 4 groups: converging, accommodating, assimilating, and diverging. The converging learning style involves education by actively solving problems. The accommodating learning style uses emotion and interpersonal relationships. The assimilating learning style learns by abstract logic. The diverging learning style learns best by observation. Chi-square analysis and analysis of variance were performed to determine significance. RESULTS: Surveys from 1994 to 2006 (91 residents, 325 responses) were analyzed. The prevalent learning style was converging (185, 57%), followed by assimilating (58, 18%), accommodating (44, 14%), and diverging (38, 12%). At the PGY 1 and 2 levels, male and female residents differed in learning style, with the accommodating learning style being relatively more frequent in women and assimilating learning style more frequent in men (Table 1, p < or = 0.001, chi-square test). Interestingly, learning style did not seem to change with advancing PGY level within the program, which suggests that individual learning styles may be constant throughout residency training. If a resident's learning style changed, it tended to be to converging. In addition, no relation exists between learning style and participation in dedicated basic science training or performance on the ABSIT/SBSE. CONCLUSIONS: Our data suggests that learning style differs between male and female general surgery residents but not with PGY level or ABSIT/SBSE performance. A greater understanding of individual learning styles may allow more refinement and tailoring of surgical programs.


Assuntos
Cirurgia Geral/educação , Internato e Residência , Aprendizagem , Adulto , Feminino , Humanos , Masculino
16.
Am J Surg ; 194(3): 349-54, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17693281

RESUMO

BACKGROUND: The extent of lymphadenectomy in colon cancer may impact potential to cure and accuracy of staging. METHODS: The Veterans Affairs Central Cancer Registry database was queried for TNM stage I-III colon adenocarcinoma patients and yielded 5,823 individuals. The number of lymph nodes examined, number positive, and the positive:examined lymph node ratio were studied with respect to overall survival by using log-rank and Kaplan-Meier analysis. RESULTS: The overall survival (OS) in stage II patients was greater with the higher number of lymph node (LN) examined. For stage II patients, the 5-year OS was 34%, 43%, 47%, and 55% for the lowest to highest quartiles (P = .007). For stage III patients, the 5-year OS was 31%, 27%, 38%, and 53% for the lowest to highest quartiles (not significant overall). OS is greater with an increased number of positive lymph nodes (P < .001). The lymph node ratio was more powerful prognostically with a 5-year OS of 27% for the highest quartile versus 44% for the lowest. CONCLUSIONS: More extensive lymphadenectomy is associated with improved OS in stage II colon cancer patients. The positive:examined LN ratio is more powerful prognostically than the number of nodes examined or LN positivity.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Neoplasias do Colo/mortalidade , Neoplasias do Colo/cirurgia , Excisão de Linfonodo , Idoso , Feminino , Humanos , Masculino , Sistema de Registros , Taxa de Sobrevida , Estados Unidos , United States Department of Veterans Affairs
18.
Am J Physiol Gastrointest Liver Physiol ; 288(1): G135-42, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15358594

RESUMO

Ischemia is the central pathogenic factor underlying a spectrum of intestinal disorders. The study of the cellular signaling responses to ischemic stress in nonepithelial cells has progressed substantially in the previous several years, but little is known about the response in epithelial cells. Unique features of the epithelial response to ischemic stress suggest differential regulation with regards to signaling. The PKC family of proteins has been implicated in ischemic stress in nonepithelial systems. The role of PKC isoforms in chemical ischemia in intestinal epithelial cells is evaluated in this study. Additionally, the phosphorylation of the F-actin cross-linking protein myristoylated alanine-rich C kinase substrate (MARCKS) is also studied. Chemical ischemia resulted in the transient activation of only the isoform PKC-epsilon as detected by translocation employing the subcellular fractionation technique. The pharmacological agonists phorbol 12-myristate 13-acetate and carbachol also led to the translocation of PKC-epsilon. By immunofluoresence, MARCKS is noted to be located at the lateral membrane under control conditions. In response to carbachol, MARCKS translocates to the cytosol, indicating its phosphorylation, which is additionally confirmed biochemically. Consistent with this observation, carbachol induces the translocation of PKC-epsilon to proximity with MARCKS at the lateral membrane. In response to chemical ischemia, MARCKS fails to translocate and phosphorylation does not increase. Additionally, the translocation of PKC-epsilon is not to the lateral membrane but rather basally. The data suggest that the differential translocation of PKC-epsilon in response to pharmacological agonists versus ischemic stress may lead to different effects on downstream targets.


Assuntos
Intestinos/citologia , Intestinos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteína Quinase C/farmacologia , Carbacol/farmacologia , Agonistas Colinérgicos/farmacologia , Células Epiteliais/fisiologia , Humanos , Hipóxia , Substrato Quinase C Rico em Alanina Miristoilada , Fosforilação , Proteína Quinase C/metabolismo , Proteína Quinase C-épsilon , Acetato de Tetradecanoilforbol/farmacologia
19.
Crit Care Med ; 31(8 Suppl): S532-7, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12907883

RESUMO

OBJECTIVE: The epithelial response to injury in the intestinal mucosa will be described. DESIGN: A comprehensive evaluation of the literature was performed to provide a thorough review of mucosal injury and repair. RESULTS: The intestinal mucosa is a rapidly proliferating sheet of epithelial cells that sustains injury in response to stresses ranging from physiologic daily digestive trauma to severe insults associated with ischemia, chemicals, and infection. Breaks in epithelial continuity impair mucosal barrier function, perturb normal absorptive and secretory transport properties, and render the host susceptible to local infection and distant organ pathology. Minor breaches are rapidly repaired by epithelial restitution, a process independent of cell proliferation. Restitution is regulated by a variety of cytokines and growth factors and is modulated by integrin-dependent interactions with the extracellular matrix. The intracellular mechanisms that control restitution are complex and involve signaling pathways that control dynamic remodeling of the actin cytoskeleton. Emerging understanding of reparative processes suggest several possible therapeutic strategies to enhance gastrointestinal wound healing. CONCLUSION: Minor epithelial injuries are repaired with the complex process of epithelial restitution independent of cell proliferation.


Assuntos
Cuidados Críticos , Estado Terminal , Enteropatias/fisiopatologia , Mucosa Intestinal/lesões , Regeneração/fisiologia , Cicatrização/fisiologia , Animais , Divisão Celular/fisiologia , Estado Terminal/terapia , Citocinas/fisiologia , Substâncias de Crescimento/fisiologia , Humanos , Enteropatias/etiologia , Mucosa Intestinal/fisiopatologia
20.
Clin Sci (Lond) ; 105(3): 383-91, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12797863

RESUMO

Evidence from a recent study indicates that glucocorticoids (GCs) mediate skeletal muscle proteolysis during sepsis via the GC receptor (GR) pathway. Attempts to identify the mechanisms regulating GR gene expression in skeletal muscle during sepsis have been hampered by the lack of an appropriate in vitro model system that can mimic in vivo septic conditions. In the present study, we report that GR gene transcription in L6 myocytes in vitro is up-regulated by treatment with sera from septic rats in a manner similar to that measured in septic rats in vivo. Sera from septic rats were collected from animals in which sepsis was induced by caecal ligation and puncture and from control rats that were sham-operated. Finally, by treating L6 myotubes with the GR antagonist RU 38486, thereby preventing sepsis-induced GR transcription, we confirmed that the possible septic effect on the GR was due to increased GCs. L6 myocytes treated with sera from septic rats might therefore be useful as an experimental model for identifying the molecular mechanisms by which the GR regulates muscle cachexia during sepsis. Furthermore, RU 38486 inhibited the sepsis-induced increase in total and myofibrillar energy-dependent protein breakdown rates in incubated extensor digitorum longus muscles from septic and sham-operated rats, as measured by release of tyrosine and 3-methylhistidine respectively. Our results demonstrate for the first time that sepsis induces GR transcription in skeletal muscle, and supports the hypothesis that the GC-induced proteolysis under sepsis is partially a consequence of GR activation.


Assuntos
Células Musculares/metabolismo , Receptores de Glucocorticoides/genética , Sepse/metabolismo , Transcrição Gênica , Animais , Linhagem Celular , Corticosterona/sangue , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Antagonistas de Hormônios/farmacologia , Hidrocortisona/farmacologia , Masculino , Camundongos , Mifepristona/farmacologia , Ratos , Ratos Sprague-Dawley , Sepse/sangue
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