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1.
J Surg Oncol ; 113(7): 721-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27040042

RESUMO

BACKGROUND AND OBJECTIVES: Invasive secretory breast carcinoma (SBC) is a rare subtype of breast malignancy. METHODS: Cases of SBC and infiltrating ductal carcinoma (IDC) from the National Cancer Database (1998-2011) were queried. RESULTS: Patients with SBC (n = 246) and IDC were identified (n = 1,564,068). The group with SBC was younger (age 56.4 ± 16.0 vs. 60.4 ± 13.9 years, P < 0.001), had similar tumor size (19.9 ± 17.8 vs. 21.6 ± 25.5 mm, P = 0.297), more frequently African-Americans (24.1 vs. 14.8 vs. 13.7; P = 0.004), more well-differentiated (32 vs. 18%, P < 0.001) and less likely to be hormone receptor positive (ER: 64 vs. 76%, P = 0.001; PR: 43 vs. 65%, P < 0.001). No differences were found for incidence of node-positivity (32 vs. 34%, P = 0.520) and stage IV presentation (2.4 vs. 3.6%, P = 0.372). Breast conserving surgery (60 vs. 58%, P = 0.405) and hormonal therapy (67 vs. 71%, P = 0.489) rates were similar. Systemic chemotherapy was used less often for SBC (38 vs. 45%, P = 0.035). The overall survival of all patients with SBC was better than all patients with IDC (median not reached vs. 14.8 years, P = 0.025). CONCLUSION: SBC is an uncommon tumor that is often well-differentiated and seen in younger women. Contrary to prior reports, they are frequently hormone receptor-positive. Compared to IDC, overall survival is improved. J. Surg. Oncol. 2016;113:721-725. © 2016 Wiley Periodicals, Inc.


Assuntos
Neoplasias da Mama , Carcinoma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma/diagnóstico , Carcinoma/epidemiologia , Carcinoma/patologia , Carcinoma/terapia , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Quimioterapia Adjuvante , Bases de Dados Factuais , Feminino , Seguimentos , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
2.
Ann Surg Oncol ; 20(2): 357-61, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22941171

RESUMO

BACKGROUND: Size of primary tumor has implications for staging, imaging, and treatment of pancreatic head carcinomas. Limited data suggest that small tumor size is associated with better survival. The objective of this population study is to analyze characteristics and survival of patients with resected pancreatic head ductal carcinomas sized <1 and 2 cm. METHODS: Analysis of resected invasive pancreatic head ductal carcinomas captured within SEER Program from 1998 to 2008. RESULTS: A total of 7,135 cases were analyzed with nodal metastases in 31, 55, and 67 % for subcentimeter, 1.1-2 cm, and >2 cm tumors, respectively. Median survival was longest for node-negative tumors (38, 26, 19 months for tumors measuring ≤ 1, 1.1-2, and >2 cm, respectively; p < 0.001) versus node-positive tumors (18, 19, 14 months, p < 0.001). In multivariate analysis, large tumor size was associated with higher risk of death (hazard ratio (HR) = 1.179 for tumors 1.1-2 cm, p = 0.152; HR = 1.665 for tumors >2 cm, p < 0.001). CONCLUSIONS: Small pancreatic cancers have a poor prognosis and surprisingly high rate of nodal involvement; therefore, they cannot be considered early cancers. Size-based screening is unlikely to save lives with current treatment options.


Assuntos
Adenocarcinoma/mortalidade , Carcinoma Ductal Pancreático/mortalidade , Neoplasias Pancreáticas/mortalidade , Pancreaticoduodenectomia/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/cirurgia , Feminino , Humanos , Masculino , Invasividade Neoplásica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Taxa de Sobrevida
3.
Ann Surg Oncol ; 19(1): 26-30, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21735324

RESUMO

BACKGROUND: Neoadjuvant therapy for pancreatic cancer is increasingly studied, but no randomized data is available to address its clinical utility. The purpose of this study is to compare the impact of the sequencing of radiation therapy and surgery on overall survival (OS) of patients, who received both pancreaticoduodenectomy and radiation therapy. METHODS: Surveillance, Epidemiology, and End Results data on pancreatic head carcinoma patients diagnosed between 1991 and 2007 was used. OS of patients receiving neoadjuvant (nRT, n=111) versus adjuvant radiation therapy (aRT, n=1839) was the primary end point. Excluded were cases in which resection or radiation therapy were omitted. RESULTS: The groups were comparable with respect to age (63±9 vs. 62±10years, P=0.490) and gender distribution. Median OS was similar in the nRT and aRT groups (19 vs. 20 months, P=0.688). On multivariate analysis, nodal status (hazard ratio [HR] 1.35, P<0.001) and age (HR 1.01/year, P<0.001) were predictive of OS, but RT sequence was not. CONCLUSIONS: Survival of patients undergoing pancreaticoduodenectomy for pancreatic head carcinoma does not seem to be affected by sequence of perioperative radiation therapy. This finding would imply that prospective studies comparing nRT to aRT is warranted to examine potential clinical benefits of nRT and can be carried out without compromising patient outcome.


Assuntos
Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/radioterapia , Terapia Neoadjuvante , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/radioterapia , Pancreaticoduodenectomia , Carcinoma Ductal Pancreático/cirurgia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/cirurgia , Prognóstico , Radioterapia Adjuvante , Programa de SEER , Taxa de Sobrevida
4.
Nature ; 427(6969): 69-72, 2004 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-14702086

RESUMO

Determining the factors that control food web interactions is a key issue in ecology. The empirical relationship between nutrient loading (total phosphorus) and phytoplankton standing stock (chlorophyll a) in lakes was described about 30 years ago and is central for managing surface water quality. The efficiency with which biomass and energy are transferred through the food web and sustain the production of higher trophic levels (such as fish) declines with nutrient loading and system productivity, but the underlying mechanisms are poorly understood. Here we show that in seston (fine particles in water) during summer, specific omega3-polyunsaturated fatty acids (omega3-PUFAs), which are important for zooplankton, are significantly correlated to the trophic status of the lake. The omega3-PUFAs octadecatetraenoic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid, but not alpha-linolenic acid, decrease on a double-logarithmic scale with increasing total phosphorus. By combining the empirical relationship between EPA-to-carbon content and total phosphorus with functional models relating EPA-to-carbon content to the growth and egg production of daphnids, we predict secondary production for this key consumer. Thus, the decreasing efficiency in energy transfer with increasing lake productivity can be explained by differences in omega3-PUFA-associated food quality at the plant-animal interface.


Assuntos
Ácidos Graxos Insaturados/análise , Cadeia Alimentar , Água Doce/química , Zooplâncton/metabolismo , Animais , Biomassa , Carbono/metabolismo , Clorofila/metabolismo , Clorofila A , Daphnia/crescimento & desenvolvimento , Daphnia/fisiologia , Alimentos , Óvulo/fisiologia , Tamanho da Partícula , Fósforo/metabolismo , Fitoplâncton/metabolismo , Estações do Ano
5.
J Water Health ; 8(2): 326-33, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20154395

RESUMO

The Sierra Nevada Mountain range serves as an important source of drinking water for the State of California. However, summer cattle grazing on federal lands affects the overall water quality yield from this essential watershed as cattle manure is washed into the lakes and streams or directly deposited into these bodies of water. This organic pollution introduces harmful microorganisms and also provides nutrients such as nitrogen and phosphorus which increase algae growth causing eutrophication of otherwise naturally oligotrophic mountain lakes and streams. Disinfection and filtration of this water by municipal water districts after it flows downstream will become increasingly costly. This will be compounded by increasing surface water temperatures and the potential for toxins release by cyanobacteria blooms. With increasing demands for clean water for a state population approaching 40 million, steps need to be implemented to mitigate the impact of cattle on the Sierra Nevada watershed. Compared to lower elevations, high elevation grazing has the greatest impact on the watershed because of fragile unforgiving ecosystems. The societal costs from non-point pollution exceed the benefit achieved through grazing of relatively few cattle at the higher elevations. We propose limiting summer cattle grazing on public lands to lower elevations, with a final goal of allowing summer grazing on public lands only below 1,500 m elevation in the Central and Northern Sierra and 2,000 m elevation in the Southern Sierra.


Assuntos
Criação de Animais Domésticos , Água Doce/microbiologia , Abastecimento de Água/normas , Animais , California , Campylobacter/isolamento & purificação , Bovinos , Mudança Climática , Enterobacteriaceae/isolamento & purificação , Eutrofização , Giardia/isolamento & purificação , Humanos
6.
J Trauma ; 69(1): 78-83, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20622581

RESUMO

BACKGROUND: Abdominal compartment syndrome and intra-abdominal hypertension cause morbidity and mortality. Body mass index (BMI) may affect intra-abdominal pressure (IAP). Knowledge of the baseline IAP in the obese and the effect of BMI are not clearly defined. METHODS: IAPs were measured in 37 morbidly obese patients undergoing elective gastric bypass. Measurements were obtained via bladder pressure using a standard technique. IAP was measured after intubation (P1) and postoperatively after extubation (P2). Data collected included age, gender, BMI, previous surgeries, comorbidities, IAP, and laparoscopic versus open procedure. RESULTS: Mean BMI was 47.7 kg/m (range, 37-71.8 kg/m), and mean age was 45 years (range, 32-64 years). P1 mean was 9.4 mm Hg +/- 0.6 mm Hg, and P2 mean was 10.0 mm Hg +/- 0.6 mm Hg. Laparoscopic versus open procedure was unrelated to postoperative IAP. Previous surgeries and comorbidities were unrelated to IAP. P1 increased as BMI increased. For each unit increase of BMI, IAP increased by 0.14 mm Hg +/- 0.07 mm Hg (p = 0.05). Higher BMI and age were independent predictors of increased P2, with IAP increased 0.23 mm Hg +/- 0.07 mm Hg for each unit BMI (p = 0.0015) and 0.20 mm Hg +/- 0.06 mm Hg for each year increase in age (p = 0.0014). CONCLUSIONS: Baseline IAP in the obese is greater than normal weight population (0-6 mm Hg), but not in range of intra-abdominal hypertension (>12 mm Hg). Postoperative status is unrelated to IAP. Elevated BMI does impact IAP, but the incremental value is small. Markedly increased IAP should not be attributed solely to elevated BMI and should be recognized as a pathologic condition.


Assuntos
Abdome/fisiopatologia , Índice de Massa Corporal , Síndromes Compartimentais/fisiopatologia , Obesidade Mórbida/fisiopatologia , Adulto , Síndromes Compartimentais/etiologia , Cuidados Críticos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Obesidade Mórbida/cirurgia , Pressão
7.
J Am Coll Surg ; 229(6): 533-540.e1, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31562911

RESUMO

BACKGROUND: We investigated the utility and safety of short-course oral probiotics among patients undergoing major abdominal operations. Perioperative probiotics can decrease length of stay and lower rates of infectious complications. We assessed whether perioperative probiotics decrease major complications among patients undergoing high-risk gastrointestinal operations in a pragmatic randomized trial. STUDY DESIGN: This double-blind trial randomized 135 patients undergoing elective major gastrointestinal operations to perioperative oral probiotic VSL#3 taken just before operation and twice daily up to 15 total doses (n = 67) or placebo (n = 68). The primary outcomes measure was 30-day composite end point of death, unplanned readmission, or any infection. RESULTS: Primary end point occurred among 17 patients in the placebo group (25.0%) vs 22 patients in the probiotic group (32.8%; p = 0.315). Thirty-day mortality was 2 (2.9%) in the placebo group compared with 1 (1.5%) in the probiotic group (p = 1.000). The placebo group patients experienced lower 30-day readmission rate (3 of 68 [4.4%]) compared with the probiotic group (11 of 67 [16.4%]; p = 0.022). None of the placebo patients were readmitted for dehydration, but 5 of 11 probiotic group patients (45%; p = 0.049) were readmitted for dehydration as a consequence of diet intolerance and/or diarrhea. There was no difference in 30-day infection rate between the groups (15 or 68 [22%] in the placebo group vs 15 of 67 [22.4%] in the probiotic group; p = 0.963). CONCLUSIONS: Perioperative use of VSL#3 probiotic did not affect 30-day composite end point of mortality, readmission, and infection rate. A significantly higher readmission rate was observed among those exposed to probiotics. Additional studies remain warranted.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Probióticos/administração & dosagem , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Incidência , Iowa/epidemiologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Resultado do Tratamento
8.
J Gastrointest Surg ; 11(3): 377-97, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17458613

RESUMO

The number of patients undergoing surgery for the treatment of obesity, and the proportion of the health care budget dedicated to this health problem, is growing exponentially. There are several competing surgical approaches for the management of morbid obesity. We review the literature relating to four of these: gastric bypass, biliopancreatic diversion, gastric banding, and gastric pacing. Our review finds that while enhancing the malabsorptive activity of these procedures may induce an incremental increase in excess body weight loss, the proportion of patients who fail to lose more than 50% of their excess body weight is similar no matter how radical is the surgery performed. There is little guidance from the literature as to appropriate patient selection for the varying procedures, and anonymously reported registries have yet to show that patients who undergo bariatric surgery have enhanced longevity. To date, the bariatric surgical community has not conducted adequately powered randomized prospective trials to elucidate key elements of the surgical procedure such as optimal bypass length, to determine whether mixed operations are superior to those that offer intake restriction only, and to define what constitutes success after bariatric surgery. As a public health measure, bariatric surgery in the United States is being pursued in an irrational manner, being concentrated in areas where there are fewer morbidly obese patients, and used disproportionately among the population of white obese females.


Assuntos
Cirurgia Bariátrica , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Contraindicações , Humanos
9.
JSLS ; 21(1)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28144128

RESUMO

BACKGROUND AND OBJECTIVES: The safety of minimally invasive esophagectomy (MIE) outside of high-volume centers has not been studied. Therefore, we evaluated our experience with the introduction of MIE in the setting of a community teaching hospital. METHODS: A retrospective cohort of all elective esophagectomy patients treated in a community hospital from 2008 through 2015 was evaluated (n = 57; open = 31 vs MIE = 26). Clavien-Dindo complication grades were recorded prospectively. RESULTS: Mean age was 63 ± 11 years (range, 30-83), mean Charlson comorbidity index was 4.5 ± 1.7 and proportion of ASA score ≥3 was 87%. The groups did not differ in age, gender distribution, or comorbidity indices. There were 108 complications observed, including 2 deaths (3.5%, both coronary events). Postoperative complication rate was 77.1% and serious complication rate (grades 3 and 4) was 50.8% in the entire cohort. The rate of serious complications was similar (58% for open vs 42% for MIE group; 2-sided P = .089). MIE operations were longer (342 ± 109 vs 425 ± 74 minutes; P = .001). Length of stay trended toward not being significantly shorter among MIE cases (15 ± 13 vs 12 ± 12 days; P = .071). Logistic regression models including MIE status were not predictive of complications. CONCLUSIONS: Introduction of MIE esophagectomy in our community hospital was associated with prolonged operative time, but no detectable adverse outcomes. Length of stay was nonsignificantly shortened by the use of MIS esophagectomy.


Assuntos
Esofagectomia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos , Adenocarcinoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/cirurgia , Estudos de Coortes , Neoplasias Esofágicas/cirurgia , Feminino , Hospitais Comunitários , Hospitais de Ensino , Humanos , Iowa , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos
10.
PLoS One ; 12(3): e0173400, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28264026

RESUMO

Using unique computer-assisted 3D reconstruction software, it was previously demonstrated that tumorigenic cell lines derived from breast tumors, when seeded in a 3D Matrigel model, grew as clonal aggregates which, after approximately 100 hours, underwent coalescence mediated by specialized cells, eventually forming a highly structured large spheroid. Non-tumorigenic cells did not undergo coalescence. Because histological sections of melanomas forming in patients suggest that melanoma cells migrate and coalesce to form tumors, we tested whether they also underwent coalescence in a 3D Matrigel model. Melanoma cells exiting fragments of three independent melanomas or from secondary cultures derived from them, and cells from the melanoma line HTB-66, all underwent coalescence mediated by specialized cells in the 3D model. Normal melanocytes did not. However, coalescence of melanoma cells differed from that of breast-derived tumorigenic cell lines in that they 1) coalesced immediately, 2) underwent coalescence as individual cells as well as aggregates, 3) underwent coalescence far faster and 4) ultimately formed long, flat, fenestrated aggregates that were extremely dynamic. A screen of 51 purified monoclonal antibodies (mAbs) targeting cell surface-associated molecules revealed that two mAbs, anti-beta 1 integrin/(CD29) and anti-CD44, blocked melanoma cell coalescence. They also blocked coalescence of tumorigenic cells derived from a breast tumor. These results add weight to the commonality of coalescence as a characteristic of tumorigenic cells, as well as the usefulness of the 3D Matrigel model and software for both investigating the mechanisms regulating tumorigenesis and screening for potential anti-tumorigenesis mAbs.


Assuntos
Anticorpos Monoclonais/farmacologia , Receptores de Hialuronatos/metabolismo , Melanoma/metabolismo , Biomarcadores , Adesão Celular , Linhagem Celular , Rastreamento de Células , Colágeno , Combinação de Medicamentos , Humanos , Integrina beta1/metabolismo , Laminina , Melanócitos/metabolismo , Melanoma/patologia , Fenótipo , Proteoglicanas , Esferoides Celulares , Células Tumorais Cultivadas
11.
Ann Thorac Surg ; 101(3): 1123-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26652139

RESUMO

BACKGROUND: The time elapsed between completion of neoadjuvant therapy and esophagectomy may influence response rate and possibly allow for avoidance of surgical intervention in selected cases ("wait and see" approach). However, a very long postradiation interval has been associated with worsened surgical outcomes in esophageal carcinoma. Therefore we analyzed outcomes of patients with invasive distal esophageal adenocarcinoma treated with neoadjuvant chemoradiation and esophagectomy based on the time elapsed between completion of neoadjuvant chemoradiation and resection. METHODS: Patients with invasive distal esophageal carcinoma diagnosed between 2003 and 2011 and treated by neoadjuvant chemoradiation followed by esophagectomy within 26 weeks were identified in the National Cancer Data Base (NCDB). Primary outcome measures were 30- and 90-day postsurgical mortality and overall survival. RESULTS: In all, 4,284 patients aged 60.3 ± 9.4 years were analyzed (mean ± standard deviation). The interval after radiation therapy until esophagectomy was 7.8 ± 3.4 weeks (median, 7.1 weeks). The postradiation interval was 8 weeks or more in 35% of patients. Thirty-day mortality was 2.9% (n = 127), and 90-day mortality was 7.8% (n = 336). A postradiation interval of 9 weeks or more was associated with increased perioperative mortality odds both at the 30-day (adjusted odds ratio [OR], 2.160; 95% confidence interval, 1.099-4.242; p = 0.025) and 90-day follow-up (adjusted OR, 1.912; 95% confidence interval, 1.290-2.835; p < 0.001). Similarly, a postradiation interval of 9 weeks or more was associated with an increased mortality risk (adjusted hazard ratio [HR], 1.194; 95% confidence interval, 1.032-1.380; p = 0.017). CONCLUSIONS: Perioperative mortality and overall survival are significantly associated with the time interval between neoadjuvant chemoradiation and esophagectomy. A "wait and see" approach after neoadjuvant therapy for esophageal adenocarcinoma may not be safe. Further studies based on more detailed data are needed.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/terapia , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/terapia , Esofagectomia/métodos , Terapia Neoadjuvante/métodos , Adenocarcinoma/patologia , Idoso , Quimiorradioterapia/métodos , Bases de Dados Factuais , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias/métodos , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Conduta Expectante/métodos
12.
PLoS One ; 10(3): e0118628, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25790299

RESUMO

We have developed a 4D computer-assisted reconstruction and motion analysis system, J3D-DIAS 4.1, and applied it to the reconstruction and motion analysis of tumorigenic cells in a 3D matrix. The system is unique in that it is fast, high-resolution, acquires optical sections using DIC microscopy (hence there is no associated photoxicity), and is capable of long-term 4D reconstruction. Specifically, a z-series at 5 µm increments can be acquired in less than a minute on tissue samples embedded in a 1.5 mm thick 3D Matrigel matrix. Reconstruction can be repeated at intervals as short as every minute and continued for 30 days or longer. Images are converted to mathematical representations from which quantitative parameters can be derived. Application of this system to cancer cells from established lines and fresh tumor tissue has revealed unique behaviors and cell types not present in non-tumorigenic lines. We report here that cells from tumorigenic lines and tumors undergo rapid coalescence in 3D, mediated by specific cell types that we have named "facilitators" and "probes." A third cell type, the "dervish", is capable of rapid movement through the gel and does not adhere to it. These cell types have never before been described. Our data suggest that tumorigenesis in vitro is a developmental process involving coalescence facilitated by specialized cells that culminates in large hollow spheres with complex architecture. The unique effects of select monoclonal antibodies on these processes demonstrate the usefulness of the model for analyzing the mechanisms of anti-cancer drugs.


Assuntos
Agregação Celular/fisiologia , Imageamento Tridimensional/métodos , Modelos Biológicos , Neoplasias/fisiopatologia , Imagem com Lapso de Tempo/métodos , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Colágeno , Combinação de Medicamentos , Humanos , Laminina , Proteoglicanas
13.
J Am Coll Surg ; 194(5): 557-66; discussion 566-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12022597

RESUMO

BACKGROUND: The magnitude of the systemic stress response is proportional to the degree of operative trauma. We hypothesized that laparoscopic gastric bypass (GBP) is associated with reduced operative trauma compared with open GBP, resulting in a lower systemic stress response. STUDY DESIGN: Forty-eight patients with a body mass index of 40 to 60 were randomly assigned to laparoscopic (n = 26) or open (n = 22) GBP Blood samples were measured at baseline and at 1, 24, 48, and 72 hours postoperatively. Metabolic (insulin, glucose, epinephrine, norepinephrine, dopamine, ACTH, cortisol), acute phase (C-reactive protein), and cytokine (interleukin [IL]-6, IL-8, tumor necrosis factor [TNF]-alpha) responses were measured. Catabolic response was also measured by calculating the nitrogen balance at 24 and 48 hours postoperatively. RESULTS: The two groups of patients were similar in terms of age, gender, and preoperative body mass index. The mean operative time was longer for laparoscopic GBP than for open GBP (229 +/- 50 versus 207 43 minutes). After laparoscopic and open GBP, plasma concentrations of insulin, glucose, epinephrine, dopamine, and cortisol increased; IL-8 and TNF-alpha remained unchanged; and negative nitrogen balances occurred at 24 and 48 hours. There was no significant difference in these parameters between groups. Concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 levels also increased, but these levels were significantly lower after laparoscopic GBP than after open GBP (p < 0.05). CONCLUSIONS: Systemic stress response after laparoscopic GBP is similar to that after open GBP, except that concentrations of norepinephrine, ACTH, C-reactive protein, and IL-6 are lower after laparoscopic than after open GBP. These findings may suggest a lower degree of operative injury after laparoscopic GBP.


Assuntos
Derivação Gástrica , Laparoscopia , Estresse Fisiológico/etiologia , Reação de Fase Aguda , Hormônio Adrenocorticotrópico/sangue , Adulto , Glicemia/metabolismo , Índice de Massa Corporal , Citocinas/sangue , Dopamina/sangue , Epinefrina/sangue , Feminino , Derivação Gástrica/métodos , Humanos , Hidrocortisona/sangue , Masculino , Nitrogênio/metabolismo , Norepinefrina/sangue , Estresse Fisiológico/metabolismo , Estresse Fisiológico/fisiopatologia , Fatores de Tempo
14.
Oecologia ; 43(3): 269-281, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28309884

RESUMO

The symbiotic fern Azolla filiculoides var. rubra, which contains a blue-green nitrogen fixing alga Anabaena azollae, fixed 164 Kg N·ha-1·ann-1 in the littoral zone of a small eutrophic lake. Associated planktonic Anabaena spp. blooms, dominated by Anabaena spiroides, fixed 29.5Kg N·ha-1·ann-1. Nitrogen fixation in both organisms was not obviously related to ambient dissolved inorganic nitrogen levels. By comparing 15N-N2 and acetylene reduction techniques, we determined a ratio of 3 moles C2H2 reduced to 1 mole of N2 fixed. Combining this with results from one diurnal investigation, it was estimated that 24% of the total daily fixation by Azolla occurred at night. Highest nitrogen fixation rates in Azolla occurred when plant density was lowest. Nitrogen fixation by planktonic Anabaena spp. generally paralleled changes in biomass. Frond breakage due to wind caused a decrease in Azolla nitrogen fixation and growth which was followed by a bloom of planktonic Anabaena spp. A second Anabaena spp. bloom was instrumental in the summer decline of Azolla. Maximum growth and nitrogen fixation of both organisms did not occur simultaneously. If physical disruption to the Azolla mat does not occur, it is likely that growth of the population would continue throughout the year.

15.
J Am Coll Surg ; 217(1): 56-62; discussion 62-3, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23623224

RESUMO

BACKGROUND: The Clinical Outcomes in Surgical Therapy trial demonstrated that laparoscopic colectomy (LC) was equivalent to open colectomy (OC) for 30-day mortality, time to recurrence, and overall survival in colon cancer (CC) patients. Current use of LC for CC is not well known. STUDY DESIGN: Surgical data were reviewed for all patients randomized into a national phase III clinical trial for adjuvant therapy in stage III CC (North Central Cancer Treatment Group trial N0147). Colon resections were grouped as open (traditional laparotomy) or laparoscopic, including laparoscopic; laparoscopic assisted; hand assisted; and laparoscopic converted to OC. Statistical methods included nonparametric methods, categorical analysis, and logistic regression modeling. RESULTS: A total of 3,393 evaluable patients were accrued between 2004 and 2009; 53% were male, median age was 58 years, 86% were white, and 70% had a body mass index >25 kg/m(2). Two thousand one hundred thirteen (62%) underwent OC. One thousand two hundred eighty (38%) were initiated as laparoscopic procedures, 25% (n = 322) were laparoscopic, 32% (n = 410) were laparoscopic assisted, 26% (n = 339) were hand assisted, and 16% (n = 209) were LC converted to OC. Significant predictors of LC (vs OC) in multivariate models were T stage (T1 or T2 vs T3 or T4; p = 0.0286), and absence of perforation, bowel obstruction, or adherence to surrounding organs (p < 0.01 each). Increasing rates of LC were observed over time, with LC eclipsing OC in 2009 (p < 0.0001). Surgical efficacy, measured by lymph node retrieval, was similar, with the mean number of lymph nodes retrieved higher in the LC group (20.6 vs 19.5 nodes; p = 0.0006). CONCLUSIONS: This study demonstrated a steadily increasing use of LC for the surgical treatment of CC between 2004 and 2009, with LC preferred by study completion. Surgical efficacy was similar in stage III CC patients.


Assuntos
Colectomia/métodos , Neoplasias do Colo/cirurgia , Laparoscopia/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Colectomia/estatística & dados numéricos , Colectomia/tendências , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Feminino , Humanos , Laparoscopia/métodos , Laparoscopia/tendências , Modelos Logísticos , Excisão de Linfonodo/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Resultado do Tratamento , Estados Unidos
16.
Front Microbiol ; 3: 331, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22993512

RESUMO

Molybdenum (Mo) is an essential micronutrient for biological assimilation of nitrogen gas and nitrate because it is present in the cofactors of nitrogenase and nitrate reductase enzymes. Although Mo is the most abundant transition metal in seawater (107 nM), it is present in low concentrations in most freshwaters, typically <20 nM. In 1960, it was discovered that primary productivity was limited by Mo scarcity (2-4 nM) in Castle Lake, a small, meso-oligotrophic lake in northern California. Follow up studies demonstrated that Mo also limited primary productivity in lakes in New Zealand, Alaska, and the Sierra Nevada. Research in the 1970s and 1980s showed that Mo limited primary productivity and nitrate uptake in Castle Lake only during periods of the growing season when nitrate concentrations were relatively high because ammonium assimilation does not require Mo. In the years since, research has shifted to investigate whether Mo limitation also occurs in marine and soil environments. Here we review studies of Mo limitation of nitrogen assimilation in natural microbial communities and pure cultures. We also summarize new data showing that the simultaneous addition of Mo and nitrate causes increased activity of proteins involved in nitrogen assimilation in the hypolimnion of Castle Lake when ammonium is scarce. Furthermore, we suggest that meter-scale Mo and oxygen depth profiles from Castle Lake are consistent with the hypothesis that nitrogen-fixing cyanobacteria in freshwater periphyton communities have higher Mo requirements than other microbial communities. Finally, we present topics for future research related to Mo bioavailability through time and with changing oxidation state.

17.
J Environ Public Health ; 2012: 760108, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22505950

RESUMO

INTRODUCTION: We evaluated periphytic algal and microbial communities to assess the influence of human and cattle impact on Sierra water quality. METHODS: 64 sites (lakes and streams from Lake Tahoe to Sequoia National Park, California) were sampled for suspended indicator bacteria and algae following standardized procedures. The potential for nonpoint pollution was divided into three categories: cattle-grazing areas (C), recreation use areas (R), or remote wildlife areas (W). RESULTS: Periphyton was found at 100% of C sites, 89% of R sites, but only 25% of W sites. Eleven species of periphytic algae were identified, including Zygnema, Ulothrix, Chlorella, Spirogyra, mixed Diatoms, and Cladophoria. Mean benthic algae coverage was 66% at C sites compared to 2% at W sites (P < 0.05). The prevalence of E. coli associated with periphyton was 100% at C sites, 25% of R sites, and 0% of W sites. Mean E. coli CFU/gm of algae detected was: C = 173,000, R = 700, W = 0. (P < 0.05). Analysis of neighboring water for E. coli bacteria >100 CFU/100 mL: C = 91%, R = 8%, W = 0 (P < 0.05). CONCLUSION: Higher periphytic algal biomass and uniform presence of periphyton-attached E. coli corresponded to watersheds exposed to summer cattle grazing. These differences suggest cattle grazing compromises water quality.


Assuntos
Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Eucariotos/classificação , Eucariotos/fisiologia , Água Doce/microbiologia , Poluição Química da Água/efeitos adversos , Animais , Bactérias/classificação , Biomassa , California , Bovinos , Carofíceas/classificação , Carofíceas/fisiologia , Clorófitas/classificação , Clorófitas/fisiologia , Diatomáceas/classificação , Diatomáceas/fisiologia , Estações do Ano
18.
J Clin Oncol ; 30(3): 263-7, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22162570

RESUMO

PURPOSE: Symptoms and complications of metastatic colorectal cancer (mCRC) differ by metastatic sites. There is a paucity of prospective survival data for patients with peritoneal carcinomatosis colorectal cancer (pcCRC). We characterized outcomes of patients with pcCRC enrolled onto two prospective randomized trials of chemotherapy and contrasted that with other manifestations of mCRC (non-pcCRC). METHODS: A total of 2,095 patients enrolled onto two prospective randomized trials were evaluated for overall survival (OS) and progression-free survival (PFS). A Cox proportional hazard model was used to assess the adjusted associations. RESULTS: The characteristics of the pcCRC group (n = 364) were similar to those of the non-pcCRC patients in median age (63 v 61 years, P = .23), sex (57% males v 61%, P = .23), and performance status (Eastern Cooperative Oncology Group performance status 0 or 1 94% v 96%, P = .06), but differed in frequency of liver (63% v 82%, P < .001) and lung metastases (27% v 34%, P = .01). Median OS (12.7 v 17.6 months, hazard ratio [HR] = 1.3; 95% CI, 1.2 to 1.5; P < .001) and PFS (5.8 v 7.2 months, HR = 1.2; 95% CI, 1.1 to 1.3; P = .001) were shorter for pcCRC versus non-pcCRC. The unfavorable prognostic influence of pcCRC remained after adjusting for age, PS, liver metastases, and other factors (OS: HR = 1.3, P < .001; PFS: HR = 1.1, P = .02). Infusional fluorouracil, leucovorin, and oxaliplatin was superior to irinotecan, leucovorin, and fluorouracil as a first-line treatment among pcCRC (HR for OS = 0.62, P = .005) and non-pcCRC patients (HR = 0.66, P < .001). CONCLUSION: pcCRC is associated with a significantly shorter OS and PFS as compared with other manifestations of mCRC. Future trials for mCRC should consider stratifying on the basis of pcCRC status.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Neoplasias Colorretais/patologia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Irinotecano , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Neoplasias Peritoneais/patologia , Estudos Prospectivos
19.
World J Emerg Surg ; 5: 21, 2010 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-20649988

RESUMO

Blunt chest trauma is commonly encountered by surgeons and is rarely associated with cardiac injuries. The incidence of cardiac injury is rare but can be rapidly fatal, requiring prompt recognition and treatment. We review the case of a 37 year-old male who was involved in a head-on motor vehicle collision at highway speed and was found to have an isolated left main coronary artery dissection. We then review the supporting literature for evaluation of blunt cardiac injuries and the treatment options for traumatic coronary dissection.

20.
Sci Total Environ ; 407(17): 4852-7, 2009 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-19539351

RESUMO

This study investigates the toxicity and post-exposure effects of dissolved microcystin (MC-LR) on the dominant copepods of the upper San Francisco Estuary (SFE), where blooms of the toxic cyanobacteria Microcystis aeruginosa coincide with record low levels in the abundance of pelagic organisms including phytoplankton, zooplankton, and fish. The potential negative impact of Microcystis on the copepods Eurytemora affinis and Pseudodiaptomus forbesi has raised concern for further depletion of high quality fish food. Response of copepods to MC-LR (MC) was determined using a 48-h standard static renewal method for acute toxicity testing. Following exposure, a life table test was performed to quantify any post-exposure impacts on survival and reproduction. The 48-h LC-50 and LC-10 values for MC were 1.55 and 0.14 mg/L for E. affinis; and 0.52 and 0.21 mg/L for P. forbesi. Copepod populations recovered once dissolved MC was removed and cultures returned to optimal conditions, suggesting no post-exposure effects of MC on copepod populations. Dissolved microcystin above 0.14 mg/L proved likely to have chronic effects on the survival of copepods in the SFE. Since such high concentrations are unlikely, toxicity from dissolved microcystin is not a direct threat to zooplankton of the SFE, and other mechanisms such as dietary exposure to Microcystis constitute a more severe risk.


Assuntos
Microcistinas/toxicidade , Água do Mar/química , Animais , Copépodes , Cianobactérias/isolamento & purificação , Cianobactérias/metabolismo , Toxinas Marinhas , Água do Mar/microbiologia , Microbiologia da Água
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