Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Ann Surg Oncol ; 27(1): 188-195, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31617122

RESUMO

BACKGROUND: Obesity and metabolic syndrome are associated with inflammatory hepatic parenchymal disease (HPD) and increased risk for recurrence after resection of colorectal liver metastases (CRLM). The independent impact of HPD on recurrence patterns has not been well defined. METHODS: The nonalcoholic fatty liver disease activity score (NAS) was used to quantify HPD including steatosis and fibrosis for all patients with completely resected CRLM between April 2003 and March 2007. Clinicopathologic factors, perioperative history, and outcomes were compared with the NAS. Fisher's exact test was used to examine the association between severe HPD (NAS ≥ 3) with clinical and perioperative characteristics. Kaplan-Meier methods were used to estimate recurrence-free survival (RFS). The cumulative incidences of recurrence [any intrahepatic recurrence (IHR), extrahepatic recurrence only (EHR), and death without recurrence (DWR)] were estimated using competing risks methods. RESULTS: Among the 357 patients included in this study, microsteatosis was noted in 124 (35%) patients, severe HPD in 31 (9%), steatohepatitis in 14 (4%), and sinusoidal injury in 36 (10%). After median follow-up of 127 months (range 4-175 months), 10-year RFS was 22% [95% confidence interval (CI) 17-27%]. Ten-year cumulative incidence for IHR, EHR, and DWR was 37%, 30%, and 12%, respectively. After controlling for confounders, NAS ≥ 3 was independently associated with higher risk of IHR [hazard ratio (HR) 1.76, 95% CI 1.07-2.90, p = 0.027] and lower risk of EHR (HR 0.18, 95% CI 0.04-0.75, p = 0.019) on multivariable analysis. CONCLUSIONS: Severe HPD was associated with increased IHR risk and decreased EHR risk. Future investigation into whether improving HPD from reversible etiologies can reduce the risk for IHR is warranted.


Assuntos
Neoplasias Colorretais/patologia , Hepatectomia , Hepatopatias/patologia , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Fígado Gorduroso/patologia , Feminino , Seguimentos , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Tecido Parenquimatoso/patologia , Prognóstico , Fatores de Risco
2.
Nat Med ; 25(10): 1607-1614, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31591597

RESUMO

Rectal cancer (RC) is a challenging disease to treat that requires chemotherapy, radiation and surgery to optimize outcomes for individual patients. No accurate model of RC exists to answer fundamental research questions relevant to patients. We established a biorepository of 65 patient-derived RC organoid cultures (tumoroids) from patients with primary, metastatic or recurrent disease. RC tumoroids retained molecular features of the tumors from which they were derived, and their ex vivo responses to clinically relevant chemotherapy and radiation treatment correlated with the clinical responses noted in individual patients' tumors. Upon engraftment into murine rectal mucosa, human RC tumoroids gave rise to invasive RC followed by metastasis to lung and liver. Importantly, engrafted tumors displayed the heterogenous sensitivity to chemotherapy observed clinically. Thus, the biology and drug sensitivity of RC clinical isolates can be efficiently interrogated using an organoid-based, ex vivo platform coupled with in vivo endoluminal propagation in animals.


Assuntos
Quimiorradioterapia , Organoides/patologia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/radioterapia , Animais , Fluoruracila/farmacologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundário , Camundongos , Metástase Neoplásica , Organoides/efeitos dos fármacos , Organoides/efeitos da radiação , Neoplasias Retais/patologia
3.
Cancer Res ; 78(12): 3163-3175, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29666061

RESUMO

Activation of the Wnt/ß-catenin signaling pathway drives colorectal cancer growth by deregulating expression of downstream target genes, including the c-myc proto-oncogene. The critical targets that mediate the functions of oncogenic c-Myc in colorectal cancer have yet to be fully elucidated. Previously, we showed that activation of PI3K/Akt/mTOR contributes to colorectal cancer growth and metastasis. Here, we show that Deptor, a suppressor of mTOR, is a direct target of Wnt/ß-catenin/c-Myc signaling in colorectal cancer cells. Inhibition of Wnt/ß-catenin or knockdown of c-Myc decreased, while activation of Wnt/ß-catenin or overexpression of c-Myc increased the expression of Deptor. c-Myc bound the promoter of Deptor and transcriptionally regulated Deptor expression. Inhibition of Wnt/ß-catenin/c-Myc signaling increased mTOR activation, and the combination of Wnt and Akt/mTOR inhibitors enhanced inhibition of colorectal cancer cell growth in vitro and in vivo Deptor expression was increased in colorectal cancer cells; knockdown of Deptor induced differentiation, decreased expression of B lymphoma Mo-MLV insertion region 1 (Bmi1), and decreased proliferation in colorectal cancer cell lines and primary human colorectal cancer cells. Importantly, our work identifies Deptor as a downstream target of the Wnt/ß-catenin/c-Myc signaling pathway, acting as a tumor promoter in colorectal cancer cells. Moreover, we provide a molecular basis for the synergistic combination of Wnt and mTOR inhibitors in treating colorectal cancer with elevated c-Myc.Significance: The mTOR inhibitor DEPTOR acts as a tumor promoter and could be a potential therapeutic target in colorectal cancer. Cancer Res; 78(12); 3163-75. ©2018 AACR.


Assuntos
Proliferação de Células/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Diferenciação Celular/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos , Camundongos Nus , Cultura Primária de Células , Regiões Promotoras Genéticas/genética , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-myc/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Exp Cell Res ; 354(2): 112-121, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28342898

RESUMO

Thermotherapy, as a method of treating cancer, has recently attracted considerable attention from basic and clinical investigators. A number of studies and clinical trials have shown that thermotherapy can be successfully used as a therapeutic approach for various cancers. However, the effects of temperature on cancer bioenergetics have not been studied in detail with a real time, microplate based, label-free detection approach. This study investigates how changes in temperature affect the bioenergetics characteristics (mitochondrial function and glycolysis) of three colorectal cancer (CRC) cell lines utilizing the Seahorse XF96 technology. Experiments were performed at 32°C, 37°C and 42°C using assay medium conditions and equipment settings adjusted to produce equal oxygen and pH levels ubiquitously at the beginning of all experiments. The results suggest that temperature significantly changes multiple components of glycolytic and mitochondrial function of all cell lines tested. Under hypothermia conditions (32°C), the extracellular acidification rates (ECAR) of CRC cells were significantly lower compared to the same basal ECAR levels measured at 37°C. Mitochondrial stress test for SW480 cells at 37°C vs 42°C demonstrated increased proton leak while all other OCR components remained unchanged (similar results were detected also for the patient-derived xenograft cells Pt.93). Interestingly, the FCCP dose response at 37°C vs 42°C show significant shifts in profiles, suggesting that single dose FCCP experiments might not be sufficient to characterize the mitochondrial metabolic potential when comparing groups, conditions or treatments. These findings provide valuable insights for the metabolic and bioenergetic changes of CRC cells under hypo- and hyperthermia conditions that could potentially lead to development of better targeted and personalized strategies for patients undergoing combined thermotherapy with chemotherapy.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Glicólise , Mitocôndrias/metabolismo , Temperatura , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Linhagem Celular Tumoral , Respiração Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Hipotermia Induzida , Mitocôndrias/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Oxigênio/metabolismo , Fenótipo , Estresse Fisiológico/efeitos dos fármacos
5.
Cell Death Dis ; 8(2): e2593, 2017 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-28151470

RESUMO

Obesity has been associated with increased incidence and mortality of a wide variety of human cancers including colorectal cancer. However, the molecular mechanism by which adipocytes regulate the metabolism of colon cancer cells remains elusive. In this study, we showed that adipocytes isolated from adipose tissues of colon cancer patients have an important role in modulating cellular metabolism to support tumor growth and survival. Abundant adipocytes were found in close association with invasive tumor cells in colon cancer patients. Co-culture of adipocytes with colon cancer cells led to a transfer of free fatty acids that released from the adipocytes to the cancer cells. Uptake of fatty acids allowed the cancer cells to survive nutrient deprivation conditions by upregulating mitochondrial fatty acid ß-oxidation. Mechanistically, co-culture of adipocytes or treating cells with fatty acids induced autophagy in colon cancer cells as a result of AMPK activation. Inhibition of autophagy attenuated the ability of cancer cells to utilize fatty acids and blocked the growth-promoting effect of adipocytes. In addition, we found that adipocytes stimulated the expression of genes associated with cancer stem cells and downregulated genes associated with intestinal epithelial cell differentiation in primary colon cancer cells and mouse tumor organoids. Importantly, the presence of adipocytes promoted the growth of xenograft tumors in vivo. Taken together, our results show that adipocytes in the tumor microenvironment serve as an energy provider and a metabolic regulator to promote the growth and survival of colon cancer cells.


Assuntos
Adipócitos/metabolismo , Autofagia/fisiologia , Neoplasias do Colo/metabolismo , Ácidos Graxos/metabolismo , Mitocôndrias/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Adipócitos/patologia , Tecido Adiposo/metabolismo , Tecido Adiposo/patologia , Animais , Autofagia/genética , Diferenciação Celular/genética , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Cocultura/métodos , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Regulação para Baixo/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Expressão Gênica/genética , Humanos , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Camundongos , Mitocôndrias/genética , Mitocôndrias/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Oxirredução , Microambiente Tumoral/genética
6.
Breast J ; 23(1): 95-99, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27633708

RESUMO

Necrotizing fasciitis is a rare, aggressive, soft-tissue infection that results in necrosis of skin, subcutaneous tissue, and fascia. It spreads rapidly and may progress to sepsis, multi-organ failure, and death. Predisposing conditions include diabetes, chronic alcoholism, advanced age, vascular disease, and immunosuppression and many cases are preceded by an injury or invasive procedure. Necrotizing soft-tissue infection of the breast is uncommon, with only a few reported cases in the literature. We present a 53-year-old diabetic woman who presented to the emergency room with several weeks of worsening breast and shoulder pain, swelling, and erythema. Upon formal evaluation by the surgical service, a necrotizing soft-tissue infection was suspected, and the patient was scheduled for emergent, surgical debridement. Because of the aggressive nature and high mortality of this disease, immediate surgical intervention, coupled with antibiotic therapy and physiologic support, is necessary to prevent complications and death.


Assuntos
Fasciite Necrosante/tratamento farmacológico , Fasciite Necrosante/cirurgia , Mastectomia Radical , Fasciite Necrosante/microbiologia , Feminino , Humanos , Pessoa de Meia-Idade
7.
HPB (Oxford) ; 19(2): 154-161, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27894845

RESUMO

BACKGROUND: We hypothesized hepato-pancreato-biliary (HPB) surgery patients are more likely to be hypercoagulable than hypocoagulable, and that bleeding risks from VTE chemoprophylaxis are low. This study sought to use thromboelastography (TEG) to compare coagulation profiles with bleeding/thrombotic events in HPB patients receiving standardized perioperative chemoprophylaxis. METHODS: Consecutive patients undergoing HPB resections by three surgeons at one institution (January 2014-December 2015) received preoperative and early postoperative VTE chemoprophylaxis and were evaluated with TEGs. Coagulation profiles were compared to bleeding/thrombotic events. RESULTS: Of 87 total patients, 83 (95.4%) received preoperative chemoprophylaxis and 100% received it postoperatively. Median estimated blood loss was 190 ml. Only 2 (2.3%) patients received intraoperative transfusions. None required transfusions at 72-hours. Only 2 were transfused within 30 days. There was 1 (1.1%) 30-day VTE event. Of 83 preoperative TEGs, 29 (34.9%) were hypercoagulable and only 8 (9.6%) were hypocoagulable/fibrinolytic. Of 73 postoperative TEGs, 34 (46.6%) were hypercoagulable and just 8 (11.0%) were hypocoagulable/fibrinolytic. . CONCLUSION: With routine perioperative chemoprophylaxis, both VTE and bleeding events were negligible. Perioperative TEG revealed a considerable proportion (46.6%) of HPB patients were hypercoagulable. HPB patients can receive standardized preoperative/early postoperative VTE chemoprophylaxis with effective results and minimal concern for perioperative hemorrhage.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Fibrinolíticos/administração & dosagem , Tromboelastografia , Trombofilia/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue , Esquema de Medicação , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Kentucky , Masculino , Pessoa de Meia-Idade , Assistência Perioperatória , Hemorragia Pós-Operatória/induzido quimicamente , Hemorragia Pós-Operatória/diagnóstico , Hemorragia Pós-Operatória/prevenção & controle , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Trombofilia/sangue , Trombofilia/complicações , Trombofilia/diagnóstico , Fatores de Tempo , Resultado do Tratamento , Tromboembolia Venosa/sangue , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia
8.
Surg Endosc ; 31(4): 1659-1666, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27519589

RESUMO

BACKGROUND: Doxycycline, a nonspecific metalloproteinase (MMP) inhibitor, has been demonstrated to impact the strength of the polypropylene (PP) mesh-repaired hernia with an increase in the deposition of collagen type 1. The impact of doxycycline with porcine acellular dermal matrices (PADM) is unknown; therefore, we evaluated the impact of doxycycline administration upon hernia repair with PP and PADM mesh. METHODS: Sprague-Dawley rats weighing ~400 g underwent laparotomy with creation of a midline ventral hernia. After a 27-day recovery, animals were randomly assigned to four groups of eight and underwent intraperitoneal underlay hernia repair with either PP or PADM. Groups were assigned to daily normal saline (S) or daily doxycycline in normal saline 10 mg/kg (D) via oral gavage for 8 weeks beginning 24 h preoperatively. Animals were euthanized at 8 weeks and underwent tensiometric testing of the abdominal wall and western blot analyses for collagen subtypes and MMPs. RESULTS: Thirty-two animals underwent successful hernia creation and repair with either PADM or PP. At 8 weeks, 15 of 16 PP-implanted animals survived with only 12 of 16 PADM-implanted animals surviving. There were no differences in the mesh to fascial interface tensiometric strength between groups. Densitometric counts in the PADM-D group demonstrated increased collagen type 1 compared to PP-S (PADM-D [1286.5], PADM-S [906.9], PP-S [700.4], p = 0.037) and decreased collagen type 3 compared to PP-S (PADM-D [7446.9], PADM-S [8507.6], PP-S [11,297.1], p = 0.01). MMP-9 levels were increased in PADM-D (PP-S vs. PADM-D, p = 0.04), while MMP-2 levels were similar between PADM-D and PADM-S, respectively. CONCLUSIONS: Collagen type 1 deposition at the mesh to fascial interface is enhanced following administration of doxycycline in ventral hernia repairs with porcine acellular dermal matrices. Doxycycline administration may have implications for enhancing hernia repair outcomes using biologic mesh.


Assuntos
Derme Acelular/metabolismo , Antibacterianos/farmacologia , Colágeno/metabolismo , Doxiciclina/farmacologia , Hérnia Ventral/metabolismo , Hérnia Ventral/cirurgia , Herniorrafia , Parede Abdominal/cirurgia , Animais , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Hérnia Ventral/patologia , Metaloproteinase 2 da Matriz/efeitos dos fármacos , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Telas Cirúrgicas , Cicatrização/efeitos dos fármacos
10.
Nature ; 533(7603): 411-5, 2016 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-27193687

RESUMO

Obesity and its associated comorbidities (for example, diabetes mellitus and hepatic steatosis) contribute to approximately 2.5 million deaths annually and are among the most prevalent and challenging conditions confronting the medical profession. Neurotensin (NT; also known as NTS), a 13-amino-acid peptide predominantly localized in specialized enteroendocrine cells of the small intestine and released by fat ingestion, facilitates fatty acid translocation in rat intestine, and stimulates the growth of various cancers. The effects of NT are mediated through three known NT receptors (NTR1, 2 and 3; also known as NTSR1, 2, and NTSR3, respectively). Increased fasting plasma levels of pro-NT (a stable NT precursor fragment produced in equimolar amounts relative to NT) are associated with increased risk of diabetes, cardiovascular disease and mortality; however, a role for NT as a causative factor in these diseases is unknown. Here we show that NT-deficient mice demonstrate significantly reduced intestinal fat absorption and are protected from obesity, hepatic steatosis and insulin resistance associated with high fat consumption. We further demonstrate that NT attenuates the activation of AMP-activated protein kinase (AMPK) and stimulates fatty acid absorption in mice and in cultured intestinal cells, and that this occurs through a mechanism involving NTR1 and NTR3 (also known as sortilin). Consistent with the findings in mice, expression of NT in Drosophila midgut enteroendocrine cells results in increased lipid accumulation in the midgut, fat body, and oenocytes (specialized hepatocyte-like cells) and decreased AMPK activation. Remarkably, in humans, we show that both obese and insulin-resistant subjects have elevated plasma concentrations of pro-NT, and in longitudinal studies among non-obese subjects, high levels of pro-NT denote a doubling of the risk of developing obesity later in life. Our findings directly link NT with increased fat absorption and obesity and suggest that NT may provide a prognostic marker of future obesity and a potential target for prevention and treatment.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Neurotensina/metabolismo , Obesidade/induzido quimicamente , Obesidade/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Linhagem Celular , Modelos Animais de Doenças , Drosophila melanogaster/citologia , Drosophila melanogaster/enzimologia , Drosophila melanogaster/metabolismo , Células Enteroendócrinas/metabolismo , Ativação Enzimática , Corpo Adiposo/metabolismo , Ácidos Graxos/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/prevenção & controle , Feminino , Humanos , Resistência à Insulina/fisiologia , Mucosa Intestinal/metabolismo , Intestinos/citologia , Metabolismo dos Lipídeos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurotensina/sangue , Neurotensina/deficiência , Neurotensina/genética , Obesidade/sangue , Obesidade/prevenção & controle , Precursores de Proteínas/sangue , Precursores de Proteínas/metabolismo
11.
Am Surg ; 82(3): 207-11, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27099055

RESUMO

Drains are commonly used after abdominal wall reconstruction (AWR) to prevent seroma formation. Drain management is subjective, and the merits and drawbacks of drains are not well understood. After receiving Institutional Review Board approval, we queried our prospectively maintained surgical database for AWR cases from 2009 to 2012 to ascertain if the number of days postoperatively that drains are left in place impacts the incidence of surgical site complications. Number of drains, drain duration, wound complications, and interval to development of complications were recorded. Wound complications were defined as superficial cellulitis, seroma, hematoma, superficial infection, and deep infection. Among 117 AWRs, we investigated the 64 cases with Centers for Disease Control grade one wound classification. Longest drain duration varied widely (2-171 days postoperatively; mean = 22 days). Cases were divided into four groups based on duration prior to removal of all drains: ≤7 days (n = 18), 8 to 14 days (n = 16), 15 to 28 days (n = 18), or ≥29 days (n = 12). No significant relationship was found between incidence of seroma/hematoma and days postoperatively of last drain removal. Wound complications increased linearly with drain time. Using logistic regression to adjust for obesity (body mass index >35kg/m(2)), drain duration >2 weeks and operative time >220 minutes, only body mass index >35 remained an independent predictor of wound occurrence, P < 0.05. Wound complications occur frequently after AWR. Wound infections occur more commonly among patients with drains in place for more than 2 weeks. Strategies to reduce drain duration require furthermore investigation.


Assuntos
Parede Abdominal/cirurgia , Drenagem , Adulto , Idoso , Drenagem/efeitos adversos , Feminino , Hérnia Ventral/cirurgia , Herniorrafia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Incerteza , Adulto Jovem
12.
J Am Coll Surg ; 222(4): 545-55, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26905188

RESUMO

BACKGROUND: There are different views on the effects of resident involvement on surgical outcomes. We hypothesized that resident participation in surgical care does not appreciably alter outcomes. STUDY DESIGN: We analyzed an American College of Surgeons NSQIP subset of inpatients having procedures with high complexity, including 4 surgical specialties (general surgery, cardiothoracic surgery, neurosurgery, and vascular surgery) with the highest mean work relative value units. We evaluated surgical outcomes in patients having procedures performed by the attending surgeon alone, or by the attending surgeon with assistance from at least one surgical resident (PGY1 to PGY≥6). Outcomes measures included operative mortality, composite morbidity, and failure to rescue (FTR). Propensity-score matching minimized the effects of nonrandom assignment of residents to procedures. RESULTS: In 266,411 patients, unmatched comparisons showed significantly higher operative mortality and composite morbidity rates, but decreased FTR, in operations performed with resident involvement. After propensity-score matching, there were small but significant resident-related increases in composite morbidity, but significant improvement in FTR. Senior-level resident involvement translated into improved outcomes, especially in cardiothoracic surgery procedures where >63.6% of procedures had PGY≥6 resident involvement. Resident involvement attenuated the significant worsening of operative mortality and FTR associated with multiple serious complications in individual patients. Measures of resource use increased modestly with resident involvement. CONCLUSIONS: We found substantial improvement in FTR with resident involvement, both in unmatched and propensity-matched comparisons. Senior-level resident participation seemed to attenuate, and even improve, surgical outcomes, despite slightly increased resource use. These results provide some reassurance about teaching paradigms.


Assuntos
Competência Clínica , Internato e Residência , Complicações Pós-Operatórias , Especialidades Cirúrgicas , Adulto , Idoso , Falha da Terapia de Resgate , Feminino , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Fatores de Risco , Estados Unidos
13.
Surg Endosc ; 30(5): 2016-21, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26264696

RESUMO

BACKGROUND: Ventral hernia is a commonly occurring surgical problem. Our earlier studies have shown that a 30 mg/kg dose of doxycycline can significantly impact the strength of polypropylene (PP) mesh in a rat hernia repair model at 6 and 12 weeks. The objective of the present study was to investigate the dose dependence of doxycycline treatment on hernia repair strengths in rats. STUDY DESIGN: Fifty-six Sprague-Dawley rats underwent hernia repair with either PP mesh (n = 28) or sutures only (primary; n = 28); both groups were further divided into four doxycycline groups of seven animals each: control (0 mg/kg), low (3 mg/kg), medium (10 mg/kg), and high (30 mg/kg). One day before hernia repair surgery, animals received doxycycline doses by gavage and continued receiving daily until euthanasia. After 8 weeks, rats were euthanized and tissue samples from hernia repaired area were collected and analyzed for tensile strength using a tensiometer (Instron, Canton, MA, USA), while MMPs 2, 3, and 9, and collagen type 1 and 3 were analyzed by western blotting. RESULTS: In mesh-repaired animals, medium and high doxycycline dose repaired mesh fascia interface (MFI) showed significant increase in tensile strength when compared to control. In the primary repaired animals, there was no significant difference in MFI tensile strength in any dose group. In medium-dose MFI, there was a significant reduction in MMPs 2, 3, and 9. In this animal group, MFI showed significant increase in collagen 1 and significant reduction in collagen type 3 when compared to control. CONCLUSION: It is possible to improve the strength of mesh-repaired tissue by administering a significantly lower dose of the drug, which has implications for translation of the findings.


Assuntos
Antibacterianos/farmacologia , Doxiciclina/farmacologia , Fáscia/efeitos dos fármacos , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Telas Cirúrgicas , Resistência à Tração/efeitos dos fármacos , Animais , Western Blotting , Colágeno Tipo I/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Colágeno Tipo III/efeitos dos fármacos , Colágeno Tipo III/metabolismo , Relação Dose-Resposta a Droga , Fáscia/metabolismo , Masculino , Metaloproteinase 2 da Matriz/efeitos dos fármacos , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/efeitos dos fármacos , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/efeitos dos fármacos , Metaloproteinase 9 da Matriz/metabolismo , Polipropilenos , Próteses e Implantes , Ratos , Ratos Sprague-Dawley , Suturas
14.
HPB (Oxford) ; 17(9): 846-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26223475

RESUMO

BACKGROUND: Select patients with peri-ampullary cancers require concomitant colon resection (CR) during a pancreaticoduodenectomy (PD) for margin-negative resections. This study analysed the impact of concomitant CR on major morbidity (MM) and mortality. METHODS: National Surgical Quality Improvement Program (NSQIP) patients undergoing PD for peri-ampullary cancers were identified from 2005 to 2012. A 4 : 1 propensity-score matched analysis isolated the impact of CR upon PD. Risk factors for 30-day MM and mortality were analysed to determine post-operative sequelae of PD+CR. RESULTS: From 10 965 PD and 159 PD+CR patients, 624 and 156, respectively, were selected for 4 : 1 matched analysis. PD+CR resulted in a higher MM and mortality (50.0% and 9.0%) versus PD alone (28.8% and 2.9%, respectively, P < 0.001). Multivariate analysis identified risk factors for MM after PD: concomitant CR [odds ratio (OR)-3.19, P < 0.001], smoking (OR-1.92, P = 0.005), a lack of functional independence (OR-3.29, P = 0.018), cardiac disease (OR-2.39, P = 0.011), decreased albumin (per g/dl, OR-1.38, P = 0.033) and a longer operative time (versus median time, OR-1.56, P = 0.029). Independent predictors of mortality included concomitant CR (OR-3.16, P = 0.010), ventilator dependence (OR-13.87, P < 0.001) and septic shock (OR-6.02, P < 0.001). CONCLUSIONS: CR was an independent predictor of MM and mortality after a PD. Patients requiring PD+CR should be identified pre-operatively, maximally optimized and referred to experienced surgeons at expert centres.


Assuntos
Colectomia/efeitos adversos , Neoplasias Duodenais/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Melhoria de Qualidade , Medição de Risco/métodos , Adolescente , Adulto , Idoso , Colectomia/métodos , Neoplasias Duodenais/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Neoplasias Pancreáticas/complicações , Pancreaticoduodenectomia/métodos , Pontuação de Propensão , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia , Adulto Jovem
16.
Oncotarget ; 6(22): 18891-904, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25970773

RESUMO

Fatty acid synthase (FASN), a lipogenic enzyme, is upregulated in colorectal cancer (CRC). Increased de novo lipid synthesis is thought to be a metabolic adaptation of cancer cells that promotes survival and metastasis; however, the mechanisms for this phenomenon are not fully understood. We show that FASN plays a role in regulation of energy homeostasis by enhancing cellular respiration in CRC. We demonstrate that endogenously synthesized lipids fuel fatty acid oxidation, particularly during metabolic stress, and maintain energy homeostasis. Increased FASN expression is associated with a decrease in activation of energy-sensing pathways and accumulation of lipid droplets in CRC cells and orthotopic CRCs. Immunohistochemical evaluation demonstrated increased expression of FASN and p62, a marker of autophagy inhibition, in primary CRCs and liver metastases compared to matched normal colonic mucosa. Our findings indicate that overexpression of FASN plays a crucial role in maintaining energy homeostasis in CRC via increased oxidation of endogenously synthesized lipids. Importantly, activation of fatty acid oxidation and consequent downregulation of stress-response signaling pathways may be key adaptation mechanisms that mediate the effects of FASN on cancer cell survival and metastasis, providing a strong rationale for targeting this pathway in advanced CRC.


Assuntos
Neoplasias Colorretais/metabolismo , Ácido Graxo Sintase Tipo I/biossíntese , Linhagem Celular Tumoral , Respiração Celular/fisiologia , Sobrevivência Celular/fisiologia , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Ácido Graxo Sintase Tipo I/antagonistas & inibidores , Ácido Graxo Sintase Tipo I/metabolismo , Glicólise , Células HCT116 , Células HT29 , Humanos , Transdução de Sinais , Ativação Transcricional , Regulação para Cima
17.
Clin Cancer Res ; 20(5): 1212-22, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24443523

RESUMO

BACKGROUND: The precise involvement of the PI3K/mTOR and RAS/MEK pathways in carcinoid tumors is not well defined. Therefore, the purpose of our study was to evaluate the role these pathways play in carcinoid cell proliferation, apoptosis, and secretion and to determine the effects of combined treatment on carcinoid tumor inhibition. METHODS: The human neuroendocrine cell lines BON (pancreatic carcinoid), NCI-H727 (lung carcinoid), and QGP-1 (somatostatinoma) were treated with either the pan-PI3K inhibitor, BKM120, or the dual PI3K-mTOR inhibitor, BEZ235, alone or in combination with the MEK inhibitor, PD0325901; proliferation, apoptosis, and protein expression were assessed. Peptide secretion was evaluated in BON and QGP-1 cells. The antiproliferative effect of BEZ235, alone or combined with PD0325901, was then tested in vivo. RESULTS: Both BKM120 and BEZ235 decreased proliferation and increased apoptosis; combination with PD0325901 significantly enhanced the antineoplastic effects of either treatment alone. In contrast, neurotensin peptide secretion was markedly stimulated with BKM120 treatment, but not BEZ235. The combination of BEZ235 + PD0325901 significantly inhibited the growth of BON xenografts without systemic toxicity. CONCLUSIONS: Both BKM120 and BEZ235 effectively inhibited neuroendocrine tumor (NET) cell proliferation and stimulated apoptosis. However, inhibition of the PI3K pathway alone with BKM120 significantly stimulated neurotensin peptide secretion; this did not occur with the dual inhibition of both PI3K and mTOR using BEZ235 suggesting that this would be a more effective treatment regimen for NETs. Moreover, the combination of BEZ235 and the MEK inhibitor PD0325901 was a safe and more effective therapy in vivo compared with single agents alone.


Assuntos
Tumores Neuroendócrinos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais/efeitos dos fármacos , Aminopiridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Benzamidas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Sinergismo Farmacológico , Humanos , Imidazóis/farmacologia , Masculino , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Morfolinas/farmacologia , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/farmacologia , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA