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1.
Artículo en Inglés | MEDLINE | ID: mdl-39010719

RESUMEN

PURPOSE: This study documents the efficacy and safety of using a Ligament Augmentation and Reconstruction System (LARS) ligament graft to augment extra-articular knee ligament reconstructions in elite athletes by reporting return-to-play (RTP) rates and levels, career longevity and complications. METHODS: A consecutive series of all extra-articular knee ligament reconstructions augmented by LARS ligaments in elite athletes undertaken by three specialist sports knee surgeons between 2013 and 2020 were reviewed. Seventy-six elite athletes, aged over 16 years old, and more than 2 years postsurgery were included. RTP was defined as competing at professional level or national/international level in amateur sport. RESULTS: There were 64 medial collateral ligament (MCL) and 12 posterolateral corner (PLC) reconstructions. Fifty-two (68.4%) underwent concomitant autograft cruciate ligament(s) reconstruction. The mean age was 25.1 years (SD ± 4.5). Most were football (35, 46.1%) or rugby players (35, 46.1%). Sixty-seven athletes (88.2%) RTP with 65 (97.0%) of these playing at the same or higher Tegner level. Fifty-six (83.6%) of the athletes that RTP were still playing at 2 years postsurgery. Twenty (57.1%) of those who had RTP and were more than 5 years postsurgery were still playing at 5 years. Six (7.9%) players required further surgery relating to the LARS/metalwork. One case had soft tissue inflammation adjacent to the proximal end of the synthetic graft, but it is unknown if this was mechanical irritation or a biological reaction. One MCL reruptured 4 years after RTP. CONCLUSION: Utilising LARS to augment extra-articular knee ligament reconstructions allows 88.2% of athletes with a variety of knee ligament injuries to return to elite sport. The low morbidity rates coupled with 57% of athletes still playing 5 years postsurgery demonstrates that the LARS is safe and effective in these cases. Although there are reports of LARS ligaments being used in MCL and PLC reconstructions, there is very little evidence investigating if they are safe and effective. This study demonstrates that LARS synthetic grafts can be safely used for MCL and PLC reconstructions in elite athletes and they permit a high RTP with a low risk of complications. LEVEL OF EVIDENCE: Level IV.

2.
J Exerc Sci Fit ; 19(3): 166-170, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33786041

RESUMEN

OBJECTIVE: The purpose of this investigation was to evaluate the effects of foam rolling (FR) and passive recovery (PR) on symptoms of delayed-onset muscle soreness (DOMS) and military-specific performance. METHODS: Twenty men and women (age: 23.6 ± 4.1 years, height: 176.4 ± 5.6 cm, and body mass: 84.7 ± 13.4 kg) completed a DOMS-inducing exercise protocol (DIP), followed by FR or PR. Four loaded military tasks (LMT) were performed 24 h later. Rating of perceived exertion (RPE) was measured during DIP and after each LMT. Rating of muscle pain (RMP) was measured prior to the LMTs and after the recovery protocols. A repeated measure analysis of variance and partial eta squared were used to compare LMT performance across baseline, FR and PR sessions. Friedman tests compared perceptual variables across baseline, FR, and PR. Wilcoxon matched-pairs signed-ranks test evaluated RPE during DIP, post-DIP, and post-recovery RMP between FR and PR. RESULTS: LMT performance times were significantly faster after FR compared to PR (stair climb: p = .038, cover position sprint: p = .011, simulated ammunition can carry: p = .003, Shuttle Run: p = .034). RPE measured during LMTs was similar across all data points. Post-recovery RMP for FR (3.0 (2.3, 4.0)) and PR (4.0 (3.0, 6.0)) were not significantly different. CONCLUSION: FR reduced the impact of DOMS on three loaded tactical performance tasks without significant reduction in perceived soreness.

3.
Br J Surg ; 107(13): 1826-1831, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32687623

RESUMEN

BACKGROUND: No formal guidelines exist for surveillance pouchoscopy following ileal pouch-anal anastomosis (IPAA) for ulcerative colitis. METHODS: All adults who had previously had IPAA for ulcerative colitis, and underwent a pouchoscopy between 1 January 2010 and 1 January 2020, were included. RESULTS: A total of 9398 pouchoscopy procedures were performed in 3672 patients. The majority of the examinations were diagnostic (8082, 86·0 per cent; 3260 patients) and the remainder were for routine surveillance (1316, 14·0 per cent; 412 patients). Thirteen patients (0·14 per cent of procedures) were found to have biopsy-proven neoplasia at the time of pouchoscopy; seven had low-grade dysplasia (LGD) (0·07 per cent; all located in the anal transition zone), none had high-grade dysplasia (HGD) and six (0·06 per cent) had invasive adenocarcinoma (4 in anal transition zone and 6 in pouch). Of the six patients with adenocarcinoma, four had neoplasia at the time of proctocolectomy (2 adenocarcinoma, 1 LGD, 1 HGD); all six were symptomatic with anal bleeding or pelvic pain at the time of pouchoscopy, had a negative surveillance pouchoscopy examination within 2 years of diagnosis of adenocarcinoma, had palpable masses on digital rectal examination, and had visible lesions at the time of pouchoscopy. CONCLUSION: Surveillance pouchoscopy is not recommended in asymptomatic patients because significant neoplasia following IPAA for ulcerative colitis is rare.


ANTECEDENTES: No existen unas recomendaciones formales para vigilancia endoscópica en pacientes a los que se les ha realizado un reservorio ileoanal (ileal pouch anal anastomosis, IPAA) por una colitis ulcerosa (ulcerative colitis, UC). MÉTODOS: Se incluyeron todos los pacientes adultos a los que se les había realizado previamente un IPAA por UC y se sometieron a una endoscopia del reservorio. RESULTADOS: Se realizaron un total de 9.398 procedimientos endoscópicos en 3.672 pacientes entre el 1/1/2010 y el 1/1/2020. La mayoría de las exploraciones fueron diagnósticas (n = 8.082; 86%; 3.260 pacientes) y el resto fueron de seguimiento (n = 1.316; 14%; 412 pacientes). Se descubrió que 13 pacientes tenían una neoplasia demostrada por biopsia (0,14%) en el momento de la endoscopia; siete pacientes tenían displasia de bajo grado (low-grade displasia, LGD) (0,074%; localizada en todos los casos en la zona de transición anal), ninguno tenía displasia de alto grado (high-grade displasia, HGD) y seis (0,064%) tenían un adenocarcinoma invasivo (cuatro en la zona de transición anal) y dos en el reservorio). De los seis pacientes con adenocarcinoma, 4 tenían neoplasia en el momento de la proctocolectomía (2 adenocarcinoma, uno LGD, uno HGD). Todos estos pacientes tenían síntomas de hemorragia anal o dolor pélvico en el momento de la endoscopia, se les había practicado una endoscopia previa reciente del reservorio en los dos años anteriores, presentaban una masa palpable en la exploración digital rectal, así como lesiones visibles en la endoscopia del reservorio. CONCLUSIÓN: La vigilancia endoscópica del reservorio no se recomienda en pacientes asintomáticos porque es raro que aparezca una neoplasia después del IPAA por UC.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Cuidados Posteriores , Colitis Ulcerosa/cirugía , Neoplasias del Colon/diagnóstico por imagen , Endoscopía Gastrointestinal , Complicaciones Posoperatorias/diagnóstico por imagen , Proctocolectomía Restauradora , Adenocarcinoma/patología , Adulto , Cuidados Posteriores/métodos , Cuidados Posteriores/estadística & datos numéricos , Anciano , Neoplasias del Colon/patología , Reservorios Cólicos/patología , Bases de Datos Factuales , Endoscopía Gastrointestinal/métodos , Endoscopía Gastrointestinal/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/patología
4.
Colorectal Dis ; 21(3): 315-325, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30565830

RESUMEN

AIM: The prognostic association between mesorectal grading and oncological outcome in patients undergoing resection for rectal adenocarcinoma is controversial. The aim of this retrospective chart review was to determine the individual impact of mesorectal grading on rectal cancer outcomes. METHOD: We compared oncological outcomes in patients with complete, near-complete and incomplete mesorectum who underwent rectal excision with curative intent from 2009 to 2014 for Stage cI-III rectal adenocarcinoma. We also assessed the independent association of mesorectal grading and oncological outcome using multivariate models including other relevant variables. RESULTS: Out of 505 patients (339 men, median age of 60 years), 347 (69%) underwent a restorative procedure. There were 452 (89.5%), 33 (6.5%) and 20 (4%) patients with a complete, near-complete and incomplete mesorectum, respectively. Local recurrence was seen in 2.4% (n = 12) patients after a mean follow-up of 3.1 ± 1.7 years. Unadjusted 3-year Kaplan-Meier analysis by mesorectal grade showed decreased rates of overall, disease-free and cancer-specific survival and increased rates of overall and distant recurrence with a near-complete mesorectum, while local recurrence was increased in cases of an incomplete mesorectum (all P < 0.05). On multivariate analyses, a near-complete mesorectum was independently associated with decreased cancer-specific survival (hazard ratio 0.26, 95% CI 0.1-0.7; P = 0.007). There were no associations between mesorectal grading and overall survival, disease-free survival, overall recurrence or distant recurrence (all P > 0.05). CONCLUSION: Mesorectal grading is independently associated with oncological outcome. It provides unique information for optimizing surgical quality in rectal cancer.


Asunto(s)
Adenocarcinoma/mortalidad , Proctectomía/mortalidad , Neoplasias del Recto/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Mesocolon/cirugía , Persona de Mediana Edad , Análisis Multivariante , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
5.
Psychol Med ; 47(8): 1389-1401, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28100283

RESUMEN

BACKGROUND: Cortisol is the primary output of the hypothalamic-pituitary-adrenal (HPA) axis and is central to the biological stress response, with wide-ranging effects on psychiatric health. Despite well-studied biological pathways of glucocorticoid function, little attention has been paid to the role of genetic variation. Conventional salivary, urinary and serum measures are strongly influenced by diurnal variation and transient reactivity. Recently developed technology can be used to measure cortisol accumulation over several months in hair, thus indexing chronic HPA function. METHOD: In a socio-economically diverse sample of 1070 twins/multiples (ages 7.80-19.47 years) from the Texas Twin Project, we estimated effects of sex, age and socio-economic status (SES) on hair concentrations of cortisol and its inactive metabolite, cortisone, along with their interactions with genetic and environmental factors. This is the first genetic study of hair neuroendocrine concentrations and the largest twin study of neuroendocrine concentrations in any tissue type. RESULTS: Glucocorticoid concentrations increased with age for females, but not males. Genetic factors accounted for approximately half of the variation in cortisol and cortisone. Shared environmental effects dissipated over adolescence. Higher SES was related to shallower increases in cortisol with age. SES was unrelated to cortisone, and did not significantly moderate genetic effects on either cortisol or cortisone. CONCLUSIONS: Genetic factors account for sizable proportions of glucocorticoid variation across the entire age range examined, whereas shared environmental influences are modest, and only apparent at earlier ages. Chronic glucocorticoid output appears to be more consistently related to biological sex, age and genotype than to experiential factors that cluster within nuclear families.

6.
Colorectal Dis ; 19(11): O386-O392, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28865167

RESUMEN

AIM: Although sporadic colorectal cancer (CRC) usually occurs in patients aged over 50, recent evidence suggests that the incidence is increasing in younger patients. Such patients are theoretically at high risk of metachronous neoplasia and may be candidates for extended prophylactic colectomy. This study aimed to define the risk of metachronous cancer/adenomas during follow-up of younger patients who underwent segmental colectomy for CRC. METHOD: A CRC database was used to identify patients aged under 50 who underwent surgery for CRC between 1994 and 2010. Patients diagnosed with hereditary cancer or inflammatory bowel disease were excluded. The primary end-points were frequency of extended resection and the rates of metachronous cancer and high-risk adenomas during follow-up. RESULTS: There were 284 young patients with a resectable primary tumour, of whom 280 (98.6%) underwent segmental resection, 3 (1%) extended resection and 1 (0.4%) local resection. Endoscopic follow-up was available for 150 of the patients who had segmental colectomy, with a mean age of 42.6 (±5.8) years at diagnosis and median follow-up time of 68 months (interquartile range 45-105). Out of these 150 patients, 4 (2.7%) developed metachronous colonic adenocarcinoma at 24, 71, 151 and 228 months after index surgery. Thirty additional patients had at least one adenoma identified during surveillance, and three had sessile serrated polyps. Out of the three patients undergoing extended resection, none had metachronous cancer or advanced adenomas at an average follow-up of 17 years. CONCLUSION: A segmental colectomy or proctectomy is adequate treatment for patients presenting with CRC under the age of 50.


Asunto(s)
Factores de Edad , Colectomía/métodos , Neoplasias Colorrectales/prevención & control , Vigilancia de la Población/métodos , Procedimientos Quirúrgicos Profilácticos/métodos , Adenoma/prevención & control , Adenoma/cirugía , Adulto , Colonoscopía/métodos , Neoplasias Colorrectales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Secundarias/prevención & control , Neoplasias Primarias Secundarias/cirugía , Estudios Retrospectivos , Factores de Riesgo
7.
Colorectal Dis ; 19(11): 1003-1012, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28481467

RESUMEN

AIM: Surgical technique constantly evolves in response to the pressure of progress. Ileal pouch anal anastomosis (IPAA) is a good example. We analysed the effect of changes in practice on the technique of IPAA and its outcomes. METHOD: Patients undergoing primary IPAA at this institution were divided into three groups by date of the IPAA: those operated from 1983 to 1993, from 1994 to 2004 and from 2005 to 2015. Demographics, patient comorbidity, surgical techniques, postoperative outcomes, pouch function and quality of life were analysed. RESULTS: In all, 4525 patients had a primary IPAA. With each decade, increasing numbers of surgeons were involved (decade I, 8; II, 16; III, 31), patients tended to be sicker (higher American Society of Anesthesiologists score) and three-staged pouches became more common. After an initial popularity of the S pouch, J pouches became dominant and a mucosectomy rate of 12% was standard. The laparoscopic technique blossomed in the last decade. 90-day postoperative morbidity by decade was 38.3% vs 50% vs 48% (P < 0.0001), but late morbidity decreased from 74.2% through 67.1% to 30% (P < 0.0001). Functional results improved, but quality of life scores did not. Pouch survival rate at 10 years was maintained (94% vs 95.2% vs 95.2%; P = 0.06). CONCLUSION: IPAA is still evolving. Despite new generations of surgeons, a more accurate diagnosis, appropriate staging and the laparoscopic technique have made IPAA a safer, more effective and enduring operation.


Asunto(s)
Laparoscopía/métodos , Laparoscopía/tendencias , Complicaciones Posoperatorias/etiología , Proctocolectomía Restauradora/métodos , Proctocolectomía Restauradora/tendencias , Humanos , Periodo Posoperatorio , Calidad de Vida , Resultado del Tratamiento
8.
Tech Coloproctol ; 20(11): 767-773, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27783175

RESUMEN

BACKGROUND: In the current study, we aimed to compare peri- and postoperative 30-day outcomes of patients undergoing laparoscopic versus open total colectomy with ileorectal anastomosis in a case-matched design using data procedure-targeted database. METHODS: Patients who underwent elective total colectomy with ileorectal anastomosis in 2012 and 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program database. Patients were divided into two groups according to the type of surgical approach (laparoscopic and open). Laparoscopic and open groups were matched (1:1) based on age, gender, diagnosis, body mass index, and American Society of Anesthesiologists classification. Comorbidities, perioperative, and short-term (30-day) postoperative outcomes were compared between the matched groups. RESULTS: We identified 1442 patients-549 in the laparoscopic group and 893 patients in the open group. After case matching, there were 326 patients in each group. There were 48 (14.7%) patients who had conversion in the laparoscopic group. The open group had a higher proportion of patients with ascites [0 (0%) vs. 7 (2.1%) p = 0.015], preoperative weight loss [26 (8.0%) vs. 45 (13.8%) p = 0.018], and contaminated wound classifications [Clean/Contaminated 261 (80%) vs. 240 (74%), Contaminated 55 (16.9%) vs. 54 (16.6%), and Dirty/Infected 8 (2.5%) vs. 28 (8.6%), (p = 0.003)]. The laparoscopic group had a significantly longer operative time (242 ± 98 vs. 202 ± 116 min, p < 0.001), shorter hospital stay (9.4 ± 8.5 vs. 13.3 ± 10.7 days, p < 0.001), and lower ileus rate (23.9 vs. 31.0%, p = 0.045) than the open group. After adjusting for covariates, the differences in terms of operative time and hospital stay remained significant [odds ratio (OR): 0.79, confidence interval (CI) 0.74-0.85 and OR 1.36, CI 1.21-1.52, p < 0.001, respectively]. CONCLUSIONS: Laparoscopic approach for total colectomy with ileorectal anastomosis is associated with a shorter hospital stay but longer operative time compared with an open approach.


Asunto(s)
Colectomía/métodos , Endoscopía Gastrointestinal/métodos , Ileostomía/métodos , Laparoscopía/métodos , Recto/cirugía , Adulto , Anciano , Estudios de Casos y Controles , Bases de Datos Factuales , Femenino , Humanos , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Tempo Operativo , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Resultado del Tratamiento
9.
Br J Surg ; 102(7): 847-52, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25832316

RESUMEN

BACKGROUND: The optimal technique for curative resection of colonic cancer includes high ligation of the mesenteric vessels, wide excision of the colonic mesentery and prevention of tumour cell spillage. This article reports results from the authors' institution for patients in whom complete mesocolic excision was performed long before the term was coined. METHODS: Patients operated on for cure for primary adenocarcinoma of the colon between January 1994 and December 2004 were identified from a prospectively maintained, institutional review board-approved, colorectal cancer registry. Medical records and operation notes were reviewed. The primary outcomes were recurrence (local and distal) and age-adjusted 5-year survival. RESULTS: Some 1013 patients (560 men and 453 women) were identified, with a median age of 69 (range 21-96) years. The most common location of the cancer was the sigmoid colon (32·9 per cent), followed by the caecum (26·7 per cent) and ascending colon (17·0 per cent). Operations were performed laparoscopically in 134 patients (13·2 per cent). Median duration of hospital stay was 7 (range 1-64, mean 8·2) days. Overall morbidity and mortality rates were 13·5 and 2·2 per cent respectively; there were 20 anastomotic leaks (2·0 per cent). Some 282 patients (27·8 per cent) had stage I, 386 (38·1 per cent) stage II and 345 (34·1 per cent) stage III disease. Median lymph node yield was 28·3 (range 0-241, mean 28·3), and 12 or more nodes were examined in 88·1 per cent of patients. Adjuvant chemotherapy was administered to 277 patients (80·3 per cent) with stage III disease. Overall local and distant recurrence rates at 5 years were 5·1 and 17·1 per cent respectively. The 5-year local recurrence rate was 2·2, 5·3 and 7·7 per cent for American Joint Committee on Cancer stages I, II and III respectively. Corresponding distant recurrence rates were 4·0, 14·7 and 30·5 per cent. The 5-year overall cancer-free age-standardized survival rate was 85·3 per cent. Five-year age standardized survival rates for patients with disease stages I, II and III were 97·7, 90·8 and 69·8 per cent respectively. CONCLUSION: These data define modern results of surgery for colonic cancer with conservative use of chemotherapy.


Asunto(s)
Colectomía/métodos , Neoplasias Colorrectales/cirugía , Laparoscopía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Morbilidad/tendencias , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Factores de Tiempo , Estados Unidos/epidemiología , Adulto Joven
10.
Br J Surg ; 102(1): 114-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25389115

RESUMEN

BACKGROUND: Germline mutations in SMAD4 and BMPR1A disrupt the transforming growth factor ß signal transduction pathway, and are associated with juvenile polyposis syndrome. The effect of genotype on the pattern of disease in this syndrome is unknown. This study evaluated the differential impact of SMAD4 and BMPR1A gene mutations on cancer risk and oncological phenotype in patients with juvenile polyposis syndrome. METHODS: Patients with juvenile polyposis syndrome and germline SMAD4 or BMPR1A mutations were identified from a prospectively maintained institutional registry. Medical records were reviewed and the clinical patterns of disease were analysed. RESULTS: Thirty-five patients had germline mutations in either BMPR1A (8 patients) or SMAD4 (27). Median follow-up was 11 years. Colonic phenotype was similar between patients with SMAD4 and BMPR1A mutations, whereas SMAD4 mutations were associated with larger polyp numbers (number of patients with 50 or more gastric polyps: 14 versus 0 respectively). The numbers of patients with rectal polyps was comparable between BMPR1A and SMAD4 mutation carriers (5 versus 17). No patient was diagnosed with cancer in the BMPR1A group, whereas four men with a SMAD4 mutation developed gastrointestinal (3) or extraintestinal (1) cancer. The gastrointestinal cancer risk in patients with juvenile polyposis syndrome and a SMAD4 mutation was 11 per cent (3 of 27). CONCLUSION: The SMAD4 genotype is associated with a more aggressive upper gastrointestinal malignancy risk in juvenile polyposis syndrome.


Asunto(s)
Receptores de Proteínas Morfogenéticas Óseas de Tipo 1/genética , Neoplasias Gastrointestinales/genética , Mutación de Línea Germinal/genética , Poliposis Intestinal/congénito , Síndromes Neoplásicos Hereditarios/genética , Proteína Smad4/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Neoplasias Gastrointestinales/cirugía , Genotipo , Humanos , Poliposis Intestinal/genética , Poliposis Intestinal/cirugía , Masculino , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/cirugía , Fenotipo , Factores de Riesgo , Adulto Joven
11.
Phys Rev Lett ; 115(5): 055001, 2015 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-26274424

RESUMEN

We report on the first layered deuterium-tritium (DT) capsule implosions indirectly driven by a "high-foot" laser pulse that were fielded in depleted uranium hohlraums at the National Ignition Facility. Recently, high-foot implosions have demonstrated improved resistance to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into the DT hot spot [Hurricane et al., Nature (London) 506, 343 (2014)]. Uranium hohlraums provide a higher albedo and thus an increased drive equivalent to an additional 25 TW laser power at the peak of the drive compared to standard gold hohlraums leading to higher implosion velocity. Additionally, we observe an improved hot-spot shape closer to round which indicates enhanced drive from the waist. In contrast to findings in the National Ignition Campaign, now all of our highest performing experiments have been done in uranium hohlraums and achieved total yields approaching 10^{16} neutrons where more than 50% of the yield was due to additional heating of alpha particles stopping in the DT fuel.

12.
Phys Rev Lett ; 114(14): 145004, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25910132

RESUMEN

Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165 µm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.

13.
Phys Rev Lett ; 114(17): 175001, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25978240

RESUMEN

Recent experiments on the National Ignition Facility [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] demonstrate that utilizing a near-vacuum hohlraum (low pressure gas-filled) is a viable option for high convergence cryogenic deuterium-tritium (DT) layered capsule implosions. This is made possible by using a dense ablator (high-density carbon), which shortens the drive duration needed to achieve high convergence: a measured 40% higher hohlraum efficiency than typical gas-filled hohlraums, which requires less laser energy going into the hohlraum, and an observed better symmetry control than anticipated by standard hydrodynamics simulations. The first series of near-vacuum hohlraum experiments culminated in a 6.8 ns, 1.2 MJ laser pulse driving a 2-shock, high adiabat (α∼3.5) cryogenic DT layered high density carbon capsule. This resulted in one of the best performances so far on the NIF relative to laser energy, with a measured primary neutron yield of 1.8×10(15) neutrons, with 20% calculated alpha heating at convergence ∼27×.

14.
J Evol Biol ; 28(9): 1600-9, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26104145

RESUMEN

Elucidating the nature of genetic variation underlying both sexually selected traits and the fitness components of sexual selection is essential to understanding the broader consequences of sexual selection as an evolutionary process. To date, there have been relatively few attempts to connect the genetic variance in sexually selected traits with segregating DNA sequence polymorphisms. We set out to address this in a well-characterized sexual selection system--the cuticular hydrocarbons (CHCs) of Drosophila serrata--using an indirect association study design that allowed simultaneous estimation of the genetic variance in CHCs, sexual fitness and single nucleotide polymorphism (SNP) effects in an outbred population. We cloned and sequenced an ortholog of the D. melanogaster desaturase 2 gene, previously shown to affect CHC biosynthesis in D. melanogaster, and associated 36 SNPs with minor allele frequencies > 0.02 with variance in CHCs and sexual fitness. Three SNPs had significant multivariate associations with CHC phenotype (q-value < 0.05). At these loci, minor alleles had multivariate effects on CHCs that were weakly associated with the multivariate direction of sexual selection operating on these traits. Two of these SNPs had pleiotropic associations with male mating success, suggesting these variants may underlie responses to sexual selection due to this locus. There were 15 significant male mating success associations (q-value < 0.1), and interestingly, we detected a nonrandom pattern in the relationship between allele frequency and direction of effect on male mating success. The minor-frequency allele usually reduced male mating success, suggesting a positive association between male mating success and total fitness at this locus.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila/genética , Ácido Graso Desaturasas/genética , Polimorfismo de Nucleótido Simple , Conducta Sexual Animal , Animales , Clonación Molecular , Femenino , Estudios de Asociación Genética , Hidrocarburos/metabolismo , Masculino , Preferencia en el Apareamiento Animal , Datos de Secuencia Molecular
15.
Tech Coloproctol ; 19(9): 521-5, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26341686

RESUMEN

PURPOSE: Data comparing surgical outcomes and quality of life (QOL) following perineal repair of rectal prolapse are limited. The aim of our study was to compare the short-term outcome and QOL of two perineal procedures in patients with rectal prolapse. METHODS: All patients with full-thickness rectal prolapse admitted to our institution and undergoing Delorme and Altemeier procedures from 2005 to 2013 were identified using an institutional, IRB-approved rectal prolapse database. Short-term outcomes and QOL were compared. RESULTS: Seventy-five patients (93% female) underwent rectal prolapse surgery: 22 Altemeier and 53 Delorme, mean age 72 ± 15 years. Sixty-six percentage of patients were ASA grade III or IV (Table 1). The median hospital stay was longer in Altemeier's group [4 (1­44) days vs. 3 (0­14) days; p = 0.01]. After a median follow-up of 13 (1­88) months, the rate of recurrent prolapse was 14% (n = 11) [Altemeier 2 (9%) vs. Delorme 9 (16%) p = 0.071]. Postoperative complication rate was 12% (n = 9) [Altemeier 5 (22%) vs. Delorme 4 (7%), p = 0.04]. There was no mortality. The Cleveland Global Quality of Life scores in each group were 0.6 ± 0.2 and 0.5 ± 0.3, respectively (p = 0.59), and were not changed by the surgery. CONCLUSIONS: In patients where abdominal repair of rectal prolapse is judged to be unwise, a Delorme procedure offers short-term control of the prolapse with low risk of complications and with reasonable function. In addition, patients that recur after a Delorme procedure can undergo another similar transanal procedure without compromising the vascular supply of the rectum.


Asunto(s)
Perineo/cirugía , Prolapso Rectal/cirugía , Cirugía Endoscópica Transanal/métodos , Anciano , Anciano de 80 o más Años , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Procedimientos Quirúrgicos del Sistema Digestivo/estadística & datos numéricos , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Calidad de Vida , Recto/cirugía , Recurrencia , Estudios Retrospectivos , Cirugía Endoscópica Transanal/estadística & datos numéricos , Resultado del Tratamiento
16.
Colorectal Dis ; 16(12): 986-94, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25141985

RESUMEN

AIM: The study aimed to establish a method for the measurement of mesenteric tension after ileal pouch-anal anastomosis (IPAA) and to evaluate the impact of tension on clinical outcome and quality of life. METHODS: All consecutive patients undergoing an open IPAA from July 2008 to October 2009 were prospectively enrolled. After the creation of the anastomosis, mesenteric tension was estimated by the surgeon in the operating room on a 10-point scale (1, least tension; 10, most tension). The association was analysed between mesenteric tension defined as low (1-2), medium (3-7) and high (8-10) and postoperative complications and quality of life (Cleveland Clinic Global Scale). RESULTS: A mesenteric tension score was obtained in 134 patients (71 men, 53.0%). Median age was 38.5 (29.3-47.0) years. Fifty-six patients (41.8%) had a low, 59 (44.0%) a medium and 19 (14.2%) a high degree of mesenteric tension. Patients with a high mesenteric tension had a shorter anal transitional zone, a longer distance from the upper border of the symphysis pubis to the apex of the small bowel loop designated for the ileoanal anastomosis, a thinner abdominal wall at the stoma site and a longer distance from the pouch to the ileostomy. The proportion of patients with high mesenteric tension was less after stapled anastomosis. On long-term follow-up, patients with high mesenteric tension were more likely to suffer from anastomotic stricture and pouch failure. Pouch function was not influenced by mesenteric tension. CONCLUSION: High mesenteric tension after IPAA is adversely associated with postoperative complications and pouch survival.


Asunto(s)
Canal Anal/cirugía , Reservorios Cólicos/efectos adversos , Íleon/cirugía , Mesenterio , Estrés Mecánico , Adulto , Anastomosis Quirúrgica/efectos adversos , Constricción Patológica/etiología , Femenino , Humanos , Masculino , Mesenterio/cirugía , Persona de Mediana Edad , Proctocolectomía Restauradora , Estudios Prospectivos , Calidad de Vida , Técnicas de Sutura , Resultado del Tratamiento
17.
Surg Endosc ; 28(5): 1588-93, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24477935

RESUMEN

BACKGROUND: Colonoscopists differ in skill, technique, and attitude in relation to the examination. These differences have a potential impact on the quality of the examination and the risk of complications. This study aimed to document differences in technique between individual colonoscopists and to explore some possible consequences to the patient and the examination. METHODS: This prospective, comparative study analyzed 10 individual endoscopists practicing in outpatient endoscopy clinics at a major medical center. Consecutive patients presenting for elective outpatient colonoscopy were included in the study. Examinations were observed, and techniques used during scope insertion and withdrawal were recorded. The type and dose of medication, the pain score recorded by the endoscopy nurses (scale of 1-10), and the incidence of hypotension and hypoxia were noted. RESULTS: The study involved 245 patients (129 men and 116 women) with a mean age of 59.5 years. The number of colonoscopies per examiner ranged from 12 to 31, with nine tenths of the examiners performing more than 20 colonoscopies. Completion rates ranged from 82.6 to 100 %; the withdrawal time averages ranged from 3.5 to 21.7 min; and the average number of techniques used ranged from one per four exams to three per exam. The average pain score per endoscopist ranged from 2.1 to 4.3, and the percentage of patients with either hypoxia or hypotension ranged from 11.5 to 85.0 %. A sedation/analgesia product (SAP) was derived by multiplying the mean dose of versed by the mean dose of meperidine. Regression analysis showed significant relationships between the number of techniques used and the levels of pain (R (2) = 0.395) and hypoxia/hypotension (R (2) = 0.513). The findings showed that SAP was significantly associated with hypoxia/hypotension (R (2) = 0.826) but not pain (R (2) = 0.01). CONCLUSIONS: Use of ancillary techniques for colonoscope insertion minimizes pain, narcotic use, and hypoxia/hypotension. The product of benzodiazepine dose and narcotic dose is a good way of assessing sedative effect.


Asunto(s)
Competencia Clínica , Colonoscopios/normas , Colonoscopía/métodos , Satisfacción del Paciente , Colonoscopía/normas , Femenino , Humanos , Hipnóticos y Sedantes/uso terapéutico , Hipotensión , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Estudios Prospectivos
18.
Tech Coloproctol ; 18(3): 265-72, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23893218

RESUMEN

BACKGROUND: Young patients with colorectal cancer (CRC) present a diagnostic and clinical challenge. The aim of our study was to survey the approaches to preoperative evaluation and clinical management of young patients with CRC by colorectal surgeons in North America. METHODS: A standard electronic survey was sent to the members of the American Society of Colon and Rectal Surgeons. The survey polled management decisions in various clinical scenarios for CRC patients less than 50 years old. Survey responses were collated and analyzed. RESULTS: One hundred ninety surgeons responded and 140 completed the entire survey (response rate 10%). Eighty percent of surgeons would offer preoperative genetic testing if the patient's family met the Amsterdam criteria compared to only 67% if the criteria were not met. Of those offering preoperative tumor testing, 48% test microsatellite instability, 19% mismatch repair protein expression by immunohistochemistry, and 24% offer both. Decisions regarding the extent of the resection for cancer were dependent on family history: Most members (86%) would perform a segmental colectomy for CRC in a patient without family history. Eighty-four percent of respondents would offer a total abdominal colectomy if preoperative tests indicated Lynch syndrome. When questioned about MYH-associated polyposis, only 27% recognized the appropriate diagnosis. CONCLUSIONS: Among the American Society of Colon and Rectal Surgeons, family history influences preoperative testing and surgical management decisions. A significant portion of surgeons do not offer preoperative genetic testing, despite implications on operative management, postoperative surveillance, and screening of family members.


Asunto(s)
Neoplasias Colorrectales/cirugía , Cirugía Colorrectal , Pautas de la Práctica en Medicina/estadística & datos numéricos , Edad de Inicio , Neoplasias Colorrectales/diagnóstico , Toma de Decisiones , Humanos , Sociedades Médicas , Encuestas y Cuestionarios , Estados Unidos
19.
Methods Mol Biol ; 2746: 147-154, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38070087

RESUMEN

The presence and progression of a neuromuscular pathology can impact on the contractile force production of a muscle. Hence, measurements of force production can be an important tool for the evaluation of disease progression. In this chapter, we describe how to perform in situ function testing on the tibialis anterior muscle using a murine model. Performing neuromuscular in situ function testing allows force measurements to be recorded in a physiologically relevant environment.


Asunto(s)
Músculo Esquelético , Fenómenos Fisiológicos del Sistema Nervioso , Ratones , Animales , Músculo Esquelético/fisiología , Contracción Muscular/fisiología
20.
Clin Genet ; 83(4): 365-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22775437

RESUMEN

Peutz-Jeghers syndrome (PJS) is an autosomal dominant disorder characterized by mucocutaneous melanocytic macules, gastrointestinal hamartomatous polyposis and an increased risk of various neoplasms. Germline mutations in the serine/threonine kinase 11 (STK11) gene have been identified as a cause for PJS. The aim of this study was to characterize the genotype of Chilean PJS patients. Mutation screening of 13 patients from eight PJS families was performed using a single strand conformation polymorphism analysis, DNA sequencing and multiplex ligation-dependent probe amplification assay. The breakpoints of the genomic rearrangements were assessed by a long-range polymerase chain reaction and sequencing. The results revealed the existence of seven different pathogenic mutations in STK11 gene in seven unrelated families, including three point mutations and four large genomic deletions. Three of these point mutations (43%, 3/7) may be considered as novel. Our results showed that a germline mutation is present in STK11 in 88% of probands fulfilling the diagnostic criteria of PJS. In this study, the combination of two different experimental approaches in the screening of the STK11 in PJS, led to a higher percentage of mutation detection.


Asunto(s)
Mutación de Línea Germinal , Síndrome de Peutz-Jeghers/genética , Mutación Puntual , Proteínas Serina-Treonina Quinasas/genética , Empalme del ARN/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Adolescente , Adulto , Niño , Preescolar , Femenino , Genotipo , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa Multiplex/métodos
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