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1.
BJS Open ; 5(5)2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34642737

RESUMEN

BACKGROUND: The quality of total mesorectal excision (TME) is regarded as a fundamental key to the oncological outcome of rectal cancer. Robotic low anterior resection (RLAR) and transanal TME (TaTME) were developed to overcome the technical challenges of conventional open TME. This study aimed to compare the short- and long-term outcomes of RLAR versus TaTME for rectal cancer. METHODS: Retrospective data from patients undergoing RLAR or TaTME at a colorectal unit in Singapore were analysed. The primary outcomes were the short-term clinical and pathological results including specimen margins and quality of TME. Secondary outcomes were recurrence, disease-free survival (DFS), and overall survival rates. RESULTS: A total of 80 patients who underwent either RLAR or TaTME were analysed. The TaTME group had a shorter operating time than the RLAR group (354 versus 481 min respectively; P < 0.001) and fewer stays in the high-dependency and intensive care units (38.1 versus 73.7 per cent; P = 0.010). There was a higher rate of readmissions at 30 days in the TaTME group (19.0 versus 0 per cent; P = 0.006). Specimens from TaTME had greater proximal (14.0 versus 10.0 cm; P = 0.045) and distal (2.50 versus 1.65 cm; P = 0.021) margins. Patients undergoing TaTME had borderline longer DFS (25.9 versus 15.7 months; P = 0.049). Subgroup analysis of patients with (y)pT3-4 tumours showed fewer positive circumferential resection margins with TaTME (0 versus 18.2 per cent; P = 0.019) and improved DFS (25.9 versus 15.7 months; P = 0.017). CONCLUSION: Superior margins were obtained with TaTME, especially in locally advanced tumours, although TaTME was associated with a higher readmission rate compared with RLAR.


Asunto(s)
Laparoscopía , Neoplasias del Recto , Procedimientos Quirúrgicos Robotizados , Cirugía Endoscópica Transanal , Humanos , Neoplasias del Recto/cirugía , Recto/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
2.
Tech Coloproctol ; 25(3): 267-278, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33386511

RESUMEN

BACKGROUND: Diabetes mellitus has been commonly associated with poor surgical outcomes. The aim of this meta-analysis was to assess the impact of diabetes on postoperative complications following colorectal surgery. METHODS: Medline, Embase and China National Knowledge Infrastructure electronic databases were reviewed from inception until May 9th 2020. Meta-analysis of proportions and comparative meta-analysis were conducted. Studies that involved patients with diabetes mellitus having colorectal surgery, with the inclusion of patients without a history of diabetes as a control, were selected. The outcomes measured were postoperative complications. RESULTS: Fifty-five studies with a total of 666,886 patients comprising 93,173 patients with diabetes and 573,713 patients without diabetes were included. Anastomotic leak (OR 2.407; 95% CI 1.837-3.155; p < 0.001), surgical site infections (OR 1.979; 95% CI 1.636-2.394; p < 0.001), urinary complications (OR 1.687; 95% CI 1.210-2.353; p = 0.002), and hospital readmissions (OR 1.406; 95% CI 1.349-1.466; p < 0.001) were found to be significantly higher amongst patients with diabetes following colorectal surgery. The incidence of septicemia, intra-abdominal infections, mechanical failure of wound healing comprising wound dehiscence and disruption, pulmonary complications, reoperation, and 30-day mortality were not significantly increased. CONCLUSIONS: This meta-analysis and systematic review found a higher incidence of postoperative complications including anastomotic leaks and a higher re-admission rate. Risk profiling for diabetes prior to surgery and perioperative optimization for patients with diabetes is critical to improve surgical outcomes.


Asunto(s)
Cirugía Colorrectal , Diabetes Mellitus , Procedimientos Quirúrgicos del Sistema Digestivo , Fuga Anastomótica/epidemiología , Fuga Anastomótica/etiología , Diabetes Mellitus/epidemiología , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología
3.
Tech Coloproctol ; 25(1): 35-48, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32851500

RESUMEN

BACKGROUND: Studies have shown differences in postoperative outcomes between two minimally invasive extraction methods for colorectal lesions-natural orifice specimen extraction surgery (NOSES) and conventional laparoscopic surgery (CLS). The aim of this study was to discover the major differences in NOSES and CLS to refine current practice. METHODS: Electronic databases were searched for articles comparing NOSES and CLS from inception till March 2020. Weighted mean differences (WMD) and odds ratio (OR) were estimated for continuous and dichotomous outcomes, respectively. Summary statistics were calculated using the DerSimonian and Laird random effects. RESULTS: Twenty-one studies (15 on malignant disease, 4 on benign disease, 2 on both) were included in this meta-analysis, totalling 2378 patients (1079 NOSE, 1299 CLS). NOSE was associated with decreased: intraoperative bleeding (WMD: - 10.652 ml; 95% CI: - 18.818 ml to - 2.482 ml; p < 0.001), pain score (WMD: - 1.520; 95% CI - 1.965 to - 1.076; p < 0.001), time to flatus (WMD: - 0.306 days; 95% CI: - 0.526 to - 0.085 days; p < 0.001), length of hospital stay (WMD: - 1.048 days; 95% CI: - 1.488 to - 0.609 days; p < 0.001), and total morbidity (OR: 0.548; 95% CI: 0.387 to 0.777; p = 0.001). Subgroup analyses showed significant differences between malignant and benign lesions for intraoperative bleeding (p = 0.011) and pain score (p = 0.010). Meta-regression analyses showed an association between the American Society of Anaesthesiologists (ASA) physical status classification III with pain (p = 0.03) and ASA III with time to flatus (p = 0.04). CONCLUSIONS: This meta-analysis and meta-regression demonstrated that NOSES had better postoperative outcomes compared to CLS. More comprehensive reviews should be conducted on the long-term outcomes specific to the extraction site to better inform clinical practice.


Asunto(s)
Neoplasias Colorrectales , Procedimientos Quirúrgicos del Sistema Digestivo , Laparoscopía , Neoplasias Colorrectales/cirugía , Humanos , Tiempo de Internación , Resultado del Tratamiento
5.
Tech Coloproctol ; 24(11): 1121-1136, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32681344

RESUMEN

BACKGROUND: Emergency surgery (ES) is the standard-of-care for left-sided obstructing colon cancer, with self-expanding metallic stents (SEMSs) and diverting colostomies (DCs) being alternative approaches. The aim of this study was to review the short- and long-term outcomes of SEMS versus ES or DC. METHODS: Embase and Medline were searched for articles comparing SEMS versus ES or DC. Primary outcomes were survival and recurrence rates. Secondary outcomes were peri- and postoperative outcomes. SEMS-specific outcomes include success and complication rates. Pooled odds ratio and 95% confidence interval were estimated with DerSimonian and Laird random effects used to account for heterogeneity. RESULTS: Thirty-three studies were included, involving 15,224 patients in 8 randomized controlled trials and 25 observational studies. There were high technical and clinical success rates for SEMS, with low rates of complications. Our meta-analysis revealed increased odds of laparoscopic surgery and anastomosis, and decreased stoma creation with SEMS compared to ES. SEMS led to fewer complications, including anastomotic leak, wound infection, ileus, myocardial infarction, and improved 90-day in-hospital mortality. There were no significant differences in 3- and 5-year overall, cancer-specific and disease-free survival. SEMS, compared to DC, led to decreased rates of stoma creation, higher rates of ileus and reoperation, and led to longer hospital stay. CONCLUSIONS: SEMS leads to better short-term outcomes but confers no survival advantage over ES. It is unclear whether SEMS has better short-term outcomes compared to DC. There is a lack of randomized trials with long-term outcomes for SEMS versus DC, hence results should be interpreted with caution.


Asunto(s)
Neoplasias del Colon , Neoplasias Colorrectales , Obstrucción Intestinal , Estomas Quirúrgicos , Neoplasias del Colon/complicaciones , Neoplasias del Colon/cirugía , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Stents , Resultado del Tratamiento
7.
Psychol Med ; 50(15): 2599-2609, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31576787

RESUMEN

BACKGROUND: Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP). METHOD: Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants' willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored. RESULTS: Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits. CONCLUSION: This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.


Asunto(s)
Cognición/fisiología , Motivación/fisiología , Desempeño Psicomotor/fisiología , Trastornos Psicóticos/psicología , Adolescente , Adulto , Antipsicóticos/farmacología , Estudios de Casos y Controles , Cognición/efectos de los fármacos , Femenino , Humanos , Masculino , Motivación/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Trastornos Psicóticos/tratamiento farmacológico , Tiempo de Reacción/efectos de los fármacos , Tiempo de Reacción/fisiología , Análisis de Regresión , Recompensa , Adulto Joven
8.
World J Surg ; 40(11): 2571-2580, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27417109

RESUMEN

INTRODUCTION: While healthcare outcomes have improved significantly, the complex management of diseases in the hospitals has also escalated the risks in patient safety. Therefore, in the process of training medical students to be proficient in medical knowledge and skills, the importance of patient safety cannot be neglected. A new innovation using mobile apps gaming system (PAtient Safety in Surgical EDucation-PASSED) to teach medical students on patient safety was created. Students were taught concepts of patient safety followed by a gaming session using iPad games created by us. This study aims to evaluate the outcome of patient safety perception using the PASSED games created. METHODS: An interactive iPad game focusing on patient safety issues was created by the undergraduate education team in the Department of Surgery, Yong Loo Lin School of Medicine at the National University of Singapore. The game employed the unique touched-screen feature with clinical scenarios extracted from the hospital sentinel events. Some of the questions were time sensitive, with extra bonus marks awarded if the student provided the correct answer within 10 s. Students could reattempt the questions if the initial answer was wrong. However, this entailed demerit points. Third-year medical students posted to the Department of Surgery experienced this gaming system in a cohort of 55-60 students. Baseline understanding of the students on patient safety was evaluated using Attitudes to Patient Safety Questionnaire III (APSQ-III) prior to the game. A 20 min talk on concept of patient safety using the WHO Patient Safety Guidelines was conducted. Following this, students downloaded the apps from ITune store and played with the game for 20-30 min. The session ended with the students completing the postintervention questionnaire. RESULTS: A total of 221 3rd year medical students responded to the survey during the PASSED session. Majority of the students felt that the PASSED game had trained them to understand the processes of medical error (p < 0.001), that their understanding on patient safety issues improved (p = 0.007), and the training prepared them to prevent medical errors (p < 0.001). Many students also recognized the importance of error reporting, where they felt comfortable reporting errors committed by themselves (p < 0.001) or by other people (p < 0.001). They also felt comfortable discussing with the supervisor on medical errors (p < 0.001). Students responded that better teamwork will reduce medical errors (p = 0.003), and teaching teamwork skills will reduce medical errors (p = 0.002). After the PASSED session, students felt that patients could play an important role in preventing medical errors (p < 0.001). They felt that patient safety should be emphasized in undergraduate training (p = 0.024). The level of understanding about concepts of patient safety was also found to improve progressively from the 2nd posting to the 5th posting for both the pre-PASSED and post-PASSED intervention. The pre-PASSED scores for Posting 2 (3.59 ± 1.931), Posting 3 (4.11 ± 1.833), Posting 4 (4.84 ± 1.653), and Posting 5 (4.88 ± 1.642) were significantly higher than the post-PASSED scores for Posting 2 (4.46 ± 2.020), Posting 3 (5.17 ± 1.845), Posting 4 (5.88 ± 1.843), and Posting 5 (5.80 ± 1.843), respectively (p < 0.001). CONCLUSION: Using iPad game (PASSED) to enhance the patient safety teaching has successfully improved the awareness and understanding of patient safety in clinical practice. This training model can be used to teach more senior medical students on the complexity of patient safety issues in medicine.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Errores Médicos/prevención & control , Aplicaciones Móviles , Seguridad del Paciente , Juegos de Video , Computadoras de Mano , Curriculum , Humanos , Encuestas y Cuestionarios
10.
Scand J Surg ; 104(4): 244-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25681056

RESUMEN

BACKGROUND: The utility of computed tomography scans of the thorax, abdomen, and pelvis for gastric cancer staging has been recommended in many countries. However, the validity of the use of computed tomography thorax in gastric cancer staging has not been challenged. METHODS: A retrospective review was conducted on our gastric cancer registry from 1998 till 2012 in the National University Hospital, Singapore. We performed computed tomography thorax only in selected cases. We defined isolated lung metastasis as the presence of suspicious findings on computed tomography thorax in the absence of metastasis elsewhere. RESULTS: A total of 808 gastric cancer cases were reviewed. The mean age of the patients was 66 years (standard deviation 13.53), and 67% were male. In all, 238 patients (30%) had metastatic disease at presentation, and 1 (0.42%) had isolated lung metastasis. The most common site of metastasis was intra-abdominal (73.8%). Among the patients who underwent surgery, the overall distant recurrence rate was 30%, of which only 83 (30%) patients had lung metastasis and all had concurrent metastasis in an intra-abdominal site. CONCLUSION: The rarity of isolated lung metastasis in gastric cancer suggests the limited value of computed tomography thorax as a routine staging tool for gastric cancers.


Asunto(s)
Tomografía Computarizada Multidetector/métodos , Estadificación de Neoplasias/métodos , Radiografía Torácica/métodos , Neoplasias Gástricas/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Gastrectomía , Humanos , Incidencia , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/secundario , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Pronóstico , Reproducibilidad de los Resultados , Estudios Retrospectivos , Singapur/epidemiología , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Adulto Joven
11.
Med J Malaysia ; 68(4): 348-52, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24145265

RESUMEN

PURPOSE: Oncologic outcomes following laparoscopic abdomino-perineal resection (APR) for distal rectal cancer are infrequently reported. This study aims to compare the long term outcomes between laparoscopic and open APR in distal rectal cancers. METHODS: A retrospective review of all patients who underwent APR for distal rectal cancer from May 2001 to November 2009 was performed. RESULTS: Forty-two patients, median age 60 (24 - 86) years, formed the study group. Laparoscopic resection was attempted in 16 patients and was successful in all but one. Patients with recurrent diseases, previous abdominal operations and neoadjuvant chemoradiation were more likely to undergo open APR. There were no differences in the T-staging, number of lymph nodes harvested or the final stage of the disease between the two groups. The laparoscopic APR group had a shorter median length of hospitalization (7 vs. 10 days, p < 0.05), but longer operative duration (300 vs. 240 minutes, p > 0.05). Excluding the 9 (21.4%) patients with metastatic disease on presentation, 13 (39.4%) developed recurrence after a median follow up of 24 (4 - 107) months. Twenty (47.6%) patients died from their advanced disease subsequently while one (2.4%) died from a noncancer related cause. Analysis showed that tumour stage and circumferential resection margin positivity were associated with a poorer survival. The types of approach had no significant impact on the survival. CONCLUSION: Laparoscopic APR for distal rectal cancer yields similar oncologic outcomes as open APR. Long-term outcome is determined by the tumour stage and circumferential resection margin and not the approach.


Asunto(s)
Recurrencia Local de Neoplasia , Neoplasias del Recto , Humanos , Laparoscopía , Recurrencia Local de Neoplasia/cirugía , Recto , Estudios Retrospectivos
12.
East Asian Arch Psychiatry ; 21(1): 32-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21837855

RESUMEN

Hashimoto's encephalopathy may present with a variety of neurological symptoms and signs, including myoclonus, epileptic seizures, disturbance of consciousness, psychosis, ataxia, and presenile dementia. This report is of a 57-year-old woman with a history of thyroid disease who was investigated for generalised seizures, rapid decline in cognitive function, increasing dependency, and gradual change in personality. High thyroid autoantibody titres confirmed the diagnosis of Hashimoto's encephalopathy and her symptoms improved with treatment with prednisolone. The differential diagnosis of presenile dementia, aetiology and pathogenesis of Hashimoto's encephalomyelitis, and treatment options are discussed. Hashimoto's encephalomyelitis should be considered in the differential diagnosis of presenile dementia, particularly in patients with a history of thyroid disease.


Asunto(s)
Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/diagnóstico , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encefalopatías/complicaciones , Encefalopatías/diagnóstico , Encefalopatías/tratamiento farmacológico , Diagnóstico Diferencial , Encefalitis , Femenino , Glucocorticoides/uso terapéutico , Enfermedad de Hashimoto/complicaciones , Enfermedad de Hashimoto/diagnóstico , Enfermedad de Hashimoto/tratamiento farmacológico , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Prednisolona/uso terapéutico , Enfermedades de la Tiroides/complicaciones , Tomografía Computarizada por Rayos X
13.
Int J Androl ; 33(5): 755-63, 2010 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20050940

RESUMEN

Androgen deficiency in the ageing male (ADAM) was proposed to characterize a symptom cluster of decrease in sexual function and strength, dysphoria and osteopenia in ageing men with decreased levels of androgens. Unlike menopause, literature on the topic is scarce and focuses mainly on the physiological aspects of the problem. However, men with ADAM also face a milieu of psychosocial stressors which may adversely affect their mental health. It is pertinent to examine ADAM within a psychological context. This study aims to determine the prevalence of symptoms of ADAM among Chinese men, and to examine their relationship with psychological distress and quality of life. A cross-sectional design was employed with standardized questionnaires to assess symptoms of ADAM and related psychological factors. The ADAM questionnaire, Hospital Anxiety and Depression Scale, Perceived Stress Scale, General Health Questionnaire and Short Form Health Survey-12 were administered to a community sample of 311 Chinese men (aged 40-80) attending a family medicine clinic in Hong Kong. Demographic information was also collected. A total of 87.8% of the sample was screened ADAM positive using the ADAM questionnaire. Age, duration of marriage, occupation, household income and physical health were found to be significantly associated with ADAM status. ADAM positive individuals were found to have higher anxiety and depression scores, higher stress level, higher psychiatric morbidity and poorer physical and mental quality of life compared with their ADAM negative counterparts. Symptoms of ADAM are prevalent among the Chinese. ADAM positivity as measured by the ADAM questionnaire is associated with poorer psychological well-being and quality of life in the ageing population. Further research and clinical attention to the psychological needs of this population is warranted.


Asunto(s)
Envejecimiento/psicología , Andrógenos/deficiencia , Pueblo Asiatico/psicología , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Ansiedad/epidemiología , Ansiedad/psicología , Trastorno Depresivo/epidemiología , Trastorno Depresivo/psicología , Encuestas Epidemiológicas , Hong Kong/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo
14.
East Asian Arch Psychiatry ; 20(4): 186-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22348928

RESUMEN

Two women presented independently with a clinical picture of mania-like psychosis after taking over-the-counter herbal slimming pills. Subsequent toxicology investigation found sibutramine in the samples of both patients. Sibutramine is an effective pharmacological treatment for obesity with a relatively favourable side-effect profile. However, neuropsychiatric side-effects of sibutramine have emerged with increasing use of the medication. Sibutramine may be associated with the development of psychotic symptoms in susceptible individuals. Further studies should aim at establishing any causal relationship between sibutramine and psychosis. There also seems to be an emerging trend of adulteration of over-the-counter slimming products with pharmaceutical analogues in Hong Kong. Physicians should be vigilant to the possibility of non-prescribed drug use when patients present with suspicious symptoms while using herbal remedies.

15.
Med J Malaysia ; 63(2): 137-9, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18942300

RESUMEN

Adolescent Idiopathic Scoliosis is a spinal deformity which affects patients' self image and confidence. Surgery is offered when the curve is more than 50 degrees based on its likelihood of progression. Studies on the radiological outcome of scoliosis correction are abundant. Therefore, it is the objective of this study to evaluate the health related quality of life in scoliosis patients who had undergone surgical correction in University Malaya Medical Center, Kuala Lumpur, Malaysia using Scoliosis Research Society-22 (SRS-22) patient questionnaire. This is a prospective evaluation of SRS-22 scores of thirty eight patients operated in our center over the past five years with a minimum follow up of one year. There were thirty two females and six males. Twenty six (68.4%) were Chinese, eight (21.1%) Malay and four (10.5%) Indian patients. The age of the patients ranged from twelve to twenty eight years, with a mean age of 18.4 +/- 3.5. Based on the King and Moe's classification, sixteen patients had King's 3 curve. The mean pre-operative Cobb angle was 68.6 degree and post-operative Cobb angle was 35.8 degree. The average curve correction was 48.5%. The overall score for SRS-22 was 4.2. The SRS-22 scores were highest for the pain domains and lowest for the functional domains. Satisfaction domain scored 4.3. The function domain scored significantly higher in those who have twenty four months or less follow up duration. Curve magnitude and the amount of correction did not significantly alter the SRS scores. In conclusion, patients were satisfied with the outcome of their operation. Although pain was common, the intensity of the pain was minimal. The amount of curve correction did not correlate with the quality of life after operation.


Asunto(s)
Calidad de Vida , Escoliosis/cirugía , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Escoliosis/fisiopatología
17.
J Nematol ; 34(3): 222-31, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19265937

RESUMEN

Integrating remote sensing and geographic information systems (GIS) technologies offers tremendous opportunities for farmers to more cost effectively manage the causes of crop stress. Initial soybean cyst nematode (SCN) population densities from 995 2-x-3-m quadrats were obtained from a soybean field near Ames, Iowa, in 2000. The percentage of sunlight reflected from each quadrat was measured weekly using a multispectral radiometer beginning in mid-May and continuing through mid-September. Aerial images were obtained at heights above the field ranging from 45 to 425 m on 12 dates during the soybean growing season. This was accomplished using color film and infrared film in conjunction with a filter to measure reflectance in the near-infrared region (810 nm). Satellite images (Landsat 7) were obtained for five dates during the 2000 growing season. Maps depicting initial SCN population densities, soybean yield, soy oil, and soy protein were generated using the GIS software program ArcView. Percentage reflectance (810 nm), aerial image intensity, and satellite image intensity data then were regressed against soybean yield, soy oil, and soy protein concentrations obtained from each geospatially referenced soybean quadrat. Percentage reflectance measurements explained up to 60% of the variation in initial SCN population densities within soybean quadrats and up to 91% of the variation in soybean yield. Aerial image and satellite image intensities explained up to 80% and 47% of the variation in soybean yield, respectively. Percentage reflectance data also explained 36% and 54% of the variation in oil and protein concentrations of the harvested soybeans, respectively. These results indicate that remote sensing coupled with GIS technologies may provide new tools to detect and quantify SCN population densities and their impacts on the quantity and quality of soybean yield.

18.
Med J Malaysia ; 54(3): 368-70, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11045066

RESUMEN

A 12 year-old Chinese schoolgirl presented with left-sided scoliosis at the age of 9 years. She has a rare defect in lipid metabolism, which is not known to be associated with spinal deformity. Her scoliotic curve deteriorated despite bracing. We report a rare occurrence of scoliosis in patient with lipodystrophy and the difficulty of using instrumented fusion in treating this condition.


Asunto(s)
Lipodistrofia/complicaciones , Escoliosis/complicaciones , Escoliosis/terapia , Adolescente , Tirantes , Femenino , Humanos , Radiografía , Retratamiento , Escoliosis/diagnóstico por imagen , Fusión Vertebral
19.
Hum Mol Genet ; 6(2): 157-64, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9063735

RESUMEN

Classical lissencephaly (smooth brain) or generalized agyria-pachygyria is a severe brain malformation which results from an arrest of neuronal migration at 9-13 weeks gestation. It has been observed in several malformation syndromes including Miller-Dieker syndrome (MDS) and isolated lissencephaly sequence (ILS). A gene containing beta-transducin like repeats, now known as LIS1, was previously mapped to the ILS/MDS chromosome region on 17p13.3. We recently localized the classical lissencephaly critical region to the LIS1 gene locus by molecular analysis of key ILS and MDS patients. We have now characterized the structure of LIS1, which consists of 11 exons, and have searched for the presence of subtle mutations in 19 ILS patients who showed no gross rearrangements of LIS1. Single strand conformational polymorphism (SSCP) analysis revealed band-shifts for three patients, each involving a different coding exon, which were not observed in their respective parental DNAs. Sequence analysis identified these de novo mutations as dA --> dG transition in exon VI at nucleotide 446, a dC --> dT transition in exon VIII at nucleotide 817, and a 22 bp deletion at the exon IX-intron 9 junction from nucleotide 988 to 1,002+7, which causes skipping of exon IX in the mature LIS1 transcript. These changes are predicted to result in an H149R amino acid substitution, an R273X premature translation termination, and abolition of amino acids 301-334, in the respective LIS1 proteins. These data thus confirm LIS1 as the gene responsible for classical lissencephaly in ILS and MDS.


Asunto(s)
Anomalías Múltiples/genética , Encéfalo/anomalías , Eliminación de Gen , Proteínas Asociadas a Microtúbulos , Mutación Puntual , Proteínas/genética , 1-Alquil-2-acetilglicerofosfocolina Esterasa , Anomalías Múltiples/etiología , Secuencia de Bases , Niño , ADN Complementario , Exones , Cara/anomalías , Humanos , Datos de Secuencia Molecular , Polimorfismo Conformacional Retorcido-Simple , Empalme del ARN , Síndrome
20.
Int J Rad Appl Instrum A ; 42(8): 767-70, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1666633

RESUMEN

New, detailed measurements have been made of the photon spectrum of the radionuclide 241Am. Observations, recorded for a 95% confidence level over local background, provide affirmation of a number of lines previously considered to be of equivocal existence. A number of hitherto unreported emissions are similarly observed. Peak areas, expressed as a percentage of that for the 59.54 keV emission, have been ascribed to all lines of the detailed spectrum. This leads to an estimated increase in the value of exposure calculated from the measured fluence spectrum, relative to that from the 59.54 keV line, of (3.1 +/- 0.8)%, taking into account all emissions beyond the predominating 59.54 keV gamma-ray emission.


Asunto(s)
Americio , Radiometría , Espectrometría gamma
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