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1.
Med J Armed Forces India ; 77(3): 287-292, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34305281

RESUMEN

BACKGROUND: Proficiency in laparoscopy is gradually achieved. After initial simulation, it is safe to move to real patients. Simulation improves the basic attributes of laparoscopy, and its non-availability hampers training. Virtual reality and commercial simulators are exorbitantly expensive. Cheaper non-commercial latest, mobile phone-based simulators appear ergonomically unsuitable. A need for a no-cost, home-based laparoscopic endotrainer was felt by authors. METHODS: The authors proposed the concept of smart TV and smart phone-based laparoscopy trainer (STELA), an almost zero cost, lightweight indigenous, cable-less box-type endotrainer, with a smart phone housed on the model, projecting to smart TV via Wi-fi direct. The simulation timings on STELA were compared with Universal Beetel endotrainer by a group of surgeons and residents using identical tasks like object transfer (OT) and knot making (KM). RESULTS: Data were analysed using SPSS, version 23.There was no significant difference in the mean timings of the residents (p > 0.05) on two endotrainers, for both tasks, and of surgeons for OT. Surgeons took significantly longer time (p < 0.05) in KM on STELA. Highest correlation (r = +.848) (<.05) was seen for KM on both devices by residents. CONCLUSION: STELA is a viable, technologically advanced, no cost alternative to the non-commercial cumbersome simulators especially for beginners.

2.
Eur J Neurol ; 27(11): 2348-2360, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32668062

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a highly contagious respiratory disease referred to as COVID-19. However, emerging evidence indicates that a small but growing number of COVID-19 patients also manifest neurological symptoms, suggesting that SARS-CoV-2 may infect the nervous system under some circumstances. SARS-CoV-2 primarily enters the body through the epithelial lining of the respiratory and gastrointestinal tracts, but under certain conditions this pleiotropic virus may also infect peripheral nerves and gain entry into the central nervous system (CNS). The brain is shielded by various anatomical and physiological barriers, most notably the blood-brain barrier (BBB) which functions to prevent harmful substances, including pathogens and pro-inflammatory mediators, from entering the brain. The BBB is composed of highly specialized endothelial cells, pericytes, mast cells and astrocytes that form the neurovascular unit, which regulates BBB permeability and maintains the integrity of the CNS. In this review, potential routes of viral entry and the possible mechanisms utilized by SARS-CoV-2 to penetrate the CNS, either by disrupting the BBB or infecting the peripheral nerves and using the neuronal network to initiate neuroinflammation, are briefly discussed. Furthermore, the long-term effects of SARS-CoV-2 infection on the brain and in the progression of neurodegenerative diseases known to be associated with other human coronaviruses are considered. Although the mechanisms of SARS-CoV-2 entry into the CNS and neurovirulence are currently unknown, the potential pathways described here might pave the way for future research in this area and enable the development of better therapeutic strategies.


Asunto(s)
COVID-19/complicaciones , Infecciones del Sistema Nervioso Central/etiología , Infecciones del Sistema Nervioso Central/virología , SARS-CoV-2/patogenicidad , Barrera Hematoencefálica/fisiopatología , COVID-19/fisiopatología , Infecciones del Sistema Nervioso Central/fisiopatología , Humanos
3.
Ann Oncol ; 30(7): 1096-1103, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31038663

RESUMEN

BACKGROUND: Microsatellite instability (MSI) is a biomarker for response to immune checkpoint inhibitors (ICPIs). PD-1 inhibitors in metastatic colorectal carcinoma (mCRC) with MSI-high (MSI-H) have demonstrated a high disease control rate and favorable progression-free survival (PFS); however, reported response rates to pembrolizumab and nivolumab are variable and often <50%, suggesting that additional predictive biomarkers are needed. METHODS: Clinicopathologic data were collected from patients with MSI-H mCRC confirmed by hybrid capture-based next-generation sequencing (NGS) treated with PD-1/L1 inhibitors at five institutes. Tumor mutational burden (TMB) was determined on 0.8-1.1 Mb of sequenced DNA and reported as mutations/Mb. Potential biomarkers of response and time to progression were analyzed by univariate and multivariate analyses. Once TMB was confirmed as a predictive biomarker, a larger dataset of 18 140 unique CRC patients was analyzed to define the relevance of the identified TMB cut-point. RESULTS: A total of 22 patients were treated with PD-1/L1 inhibitors including 19 with pembrolizumab monotherapy. Among tested variables, TMB showed the strongest association with objective response (OR; P < 0.001) and PFS, by univariate (P < 0.001) and multivariate analysis (P < 0.01). Using log-rank statistics, the optimal predictive cut-point for TMB was estimated between 37 and 41 mutations/Mb. All 13 TMBhigh cases responded, while 6/9 TMBlow cases had progressive disease. The median PFS for TMBhigh has not been reached (median follow-up >18 months) while the median PFS for TMBlow was 2 months. A TMB of 37.4 mutations/Mb in a large MSI-H mCRC population (821/18, 140 cases; 4.5%) evaluated by NGS corresponded to the 35th percentile cut-point. CONCLUSIONS: TMB appears to be an important independent biomarker within MSI-H mCRC to stratify patients for likelihood of response to ICPIs. If validated in prospective studies, TMB may play an important role in guiding the sequencing and/or combinations of ICPIs in MSI-H mCRC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Mutación , Neoplasias Peritoneales/secundario , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/administración & dosificación , Antígeno B7-H1/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Hepáticas/genética , Metástasis Linfática , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Nivolumab/administración & dosificación , Neoplasias Peritoneales/tratamiento farmacológico , Neoplasias Peritoneales/genética , Pronóstico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Estudios Retrospectivos , Tasa de Supervivencia
4.
Med J Armed Forces India ; 75(2): 204-210, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31065191

RESUMEN

BACKGROUND: Ureteroscopic management of ureteral calculi using topical anaesthesia has been described. Most studies topically anaesthetized the urethra or urinary bladder by instilling 2% of plain lignocaine. In addition to the success rate, the pain perception in these studies was reported subjectively using non-standard criteria. Topical anaesthesia of the ipsilateral ureter and the pelvicalyceal system (PCS), in addition to urethra and urinary bladder, and use of alkalinised lignocaine, for enhanced effect, has not been reported for ureteroscopy. Using these conceptual alterations, we tested the safety and efficacy of performing ureteroscopy and laser lithotripsy under our technique of total intraluminal topical anaesthesia (TILTA). METHODS: One hundred sixty-eight patients underwent ureteroscopic laser lithotripsy by topical instillation of alkalinised lignocaine into the urinary bladder and ipsilateral ureter and PCS. Self-assessed pain perception and changes in vital parameters were objectively scored at various times. The success rate, reasons for failure, maximum pain scores, complications, and willingness to undergo repeat procedure were recorded. RESULTS: The success rate was 91.3% with a mean duration of 14.7 minutes Double J Stent (DJS) was placed in 38.1%. 61.3% patients did not need any postoperative injectable analgesic, with 11.3% requiring more than a single dose. The intraoperative changes in vitals initially and at the height of pain were not statistically significant (p>0.05). Self-assessed median pain scores between intravenous access placement and ureteroscopy were significantly different (p<0.05). CONCLUSIONS: Ureteroscopy, effectively performed under TILTA, is safe with a high success rate. The acceptable pain tolerance and the shortened convalescence in addition makes the procedure's success worth the pain.

5.
Eur Arch Otorhinolaryngol ; 275(5): 1103-1110, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29605865

RESUMEN

AIMS: The frequency of the use of intratympanic steroids (ITS) as a treatment for idiopathic sudden sensorineural hearing loss (ISSNHL) in Europe is still unknown and remains a contentious issue amongst otolaryngologists. We undertook a survey of otolaryngologists in Germany and Austria to establish if there is any professional consensus with which to form a protocol for its use. METHODS: A survey of 21 questions was distributed electronically to otolaryngologists in Germany and Austria and data on demographics, indications for intratympanic treatment, procedure, follow-up, and outcomes were analysed. RESULTS: We received 908 responses. 49.1% of otolaryngologists used ITS for ISSNHL. Of those otolaryngologists who use ITS, 73.7% do not use it as primary treatment. 20.6% use ITS in conjunction with oral steroids for primary treatment and only 5.8% use ITS as monotherapy for primary treatment. 90.5% use ITS as salvage therapy. 81.1% do not consider the use of ITS after 2 weeks from the onset of symptoms. 8.3% used a tympanostomy tube and while the most commonly used steroid was dexamethasone at a concentration of 4 mg/ml (61%), a wide variety or other steroids and concentrations were used. CONCLUSIONS: This survey illustrates wide variation of current practice of intratympanic corticosteroid injection for ISSHL in Germany and Austria. In the absence of high-level evidence, knowing what current practice is allows clinicians to assess what they do against what their colleagues are doing, and if they do something very different, make them question their practice. Moreover, the obtained data will help to direct future clinical trials with the aim to compare the outcomes of more commonly used protocols.


Asunto(s)
Antiinflamatorios/uso terapéutico , Dexametasona/uso terapéutico , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Súbita/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Austria , Esquema de Medicación , Alemania , Humanos , Inyección Intratimpánica , Otolaringología , Encuestas y Cuestionarios , Resultado del Tratamiento
6.
Med J Armed Forces India ; 73(1): 36-41, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28123243

RESUMEN

BACKGROUND: The prevalence of stress urinary incontinence (SUI) in the middle-aged Indian women is around 16%. The use of transvaginal tapes (TVTs) has revolutionised the surgical management of SUI. Patients who undergo placement of the tape via the transobturator route often complain of persistent thigh pain at the site of trocar insertion. The use of minimally invasive tapes with a single suburethral incision reduces surgical trauma by eliminating thigh incisions, while maintaining the cure achieved by conventional TVTs. The study was conducted to test the efficacy and safety of minimally invasive TVT-Secur tape placement for treatment of SUI in women. METHODS: 20 women with stress incontinence were implanted with TVT-Secur tapes and followed up for a year. RESULTS: The objective cure rate of SUI was 85% at the end of a year. The improvement in the patient satisfaction and Incontinence-specific QOL scores, of both Urogenital Distress Inventory (UDI-6) and Incontinence Impact Questionnaire-7 (IIQ-7), was statistically significant at 95% and 99% confidence levels. There were no complaints of thigh pain; however, there were intraoperative complications in the form of bladder perforation in 5% (n = 1), urethral injury in 5% (n = 1) and urethral tape exposure in 10% (n = 2), at 3 months requiring tape sectioning. CONCLUSIONS: These cure rates and complications are comparable to the standard TVT implantations at the end of a year, without thigh pain; however, a greater number of patients and a longer follow-up is required to see whether the long-term cure is maintained or not, before recommending the same as a standard of treatment.

7.
HIV Med ; 16(3): 168-75, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25656740

RESUMEN

OBJECTIVES: Outbreaks of shigellosis have been documented in men who have sex with men (MSM), associated with interpersonal transmission and underlying HIV infection. We observed a rise in Shigella flexneri isolates identified in a downtown tertiary-care hospital laboratory located within the city centre community health area (CHA-1) of Vancouver, Canada. The objectives of this study were to evaluate clinical outcomes of shigellosis cases among MSM admitted to hospital and to evaluate trends in Shigella cases within Vancouver, Canada. METHODS: Adult rates of shigellosis were analysed by gender and health region, from 2005 to 2011, followed by retrospective chart review of all hospital laboratory-identified S. flexneri cases from 2008 to 2012. Serotyping and pulsed-field gel electrophoresis (PFGE) were performed on these isolates. RESULTS: Although shigellosis rates in men within CHA-1 did not change from 2005 to 2011 (range 33.4-68.5 per 100 000; P = 0.74), they were significantly higher than in other regions within the city of Vancouver (P ≤ 0.001) and the province of British Columbia (P ≤ 0.001). Shigella flexneri rates in men within CHA-1 increased significantly (range 2.3-51.4 per 100 000; P < 0.001), starting in 2008, and were higher than in other regions within Vancouver (P ≤ 0.01). Seventy-nine isolates of S. flexneri from 72 patients were identified by a single hospital laboratory. All patients were male and predominantly MSM (91.7%) and HIV-infected (86.1%), with most (92.6%) demonstrating CD4 counts ≥ 200 cells/µL. In total, 38.0% required hospitalization. Most (87.3%) had S. flexneri serotype 1 infection, with 72.9% of these representing a single PFGE pattern. CONCLUSIONS: We identified high levels of transmission of a primarily clonal strain of S. flexneri serotype 1 in our local MSM population, resulting in a substantial burden of illness and health care resource use secondary to hospital admissions.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Disentería Bacilar/epidemiología , Infecciones por VIH/complicaciones , Homosexualidad Masculina , Shigella flexneri/aislamiento & purificación , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Infecciones Oportunistas Relacionadas con el SIDA/transmisión , Adulto , Colombia Británica/epidemiología , Costo de Enfermedad , Brotes de Enfermedades , Disentería Bacilar/inmunología , Disentería Bacilar/prevención & control , Disentería Bacilar/transmisión , Electroforesis en Gel de Campo Pulsado , Infecciones por VIH/inmunología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Vigilancia en Salud Pública , Estudios Retrospectivos , Factores de Riesgo , Serotipificación , Shigella flexneri/inmunología
8.
Gerontology ; 60(2): 163-73, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24356488

RESUMEN

OBJECTIVES: This study examines older people's use of information and communication technologies (ICTs) and identifies the factors which can prevent or promote their sustained use. METHODS: A mixed methods approach was adopted. Quantitative and qualitative data were collected by a survey of 323 older ICT users (aged ≥50 years) between 2011 and 2012. These data were supplemented by qualitative data obtained through in-depth interviews, focus groups and storytelling. Quantitative data were analysed using PASW including bivariate and multivariate analyses. Qualitative data were analysed using an inductive, thematic approach. RESULTS: The findings show that, contrary to some stereotypes, many older people are enthusiastic, competent and confident users of ICTs. However, they report a range of challenges in reaching and maintaining this situation. These include technological complexity and change, age-related capability changes and a lack of learning and support mechanisms. Intrinsic motivation and social support are important in enabling older people to overcome these challenges. DISCUSSION: Getting older people online has been a high priority in many countries over the past decade. However, little attention has been paid to whether and how their usage can be sustained over time. We discuss the implications of the findings for policy and practice.


Asunto(s)
Envejecimiento/psicología , Medios de Comunicación , Alfabetización Digital , Informática , Anciano , Anciano de 80 o más Años , Medios de Comunicación/estadística & datos numéricos , Femenino , Grupos Focales , Humanos , Informática/educación , Masculino , Persona de Mediana Edad , Motivación , Encuestas y Cuestionarios , Reino Unido , Interfaz Usuario-Computador
10.
Gynecol Oncol ; 125(2): 404-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22285844

RESUMEN

OBJECTIVE: To update our report on the outcome of patients who underwent extended pelvic resection (EPR) for recurrent or persistent uterine and cervical malignancies. METHODS: We reviewed the records of all patients who underwent EPR between 6/2000 and 07/2011. EPR was defined as an en-bloc resection of a pelvic tumor with sidewall muscle, bone, major nerve, and/or major vascular structure. Complications up to 180 days post surgery were analyzed. Survivals were estimated using the Kaplan-Meier method. RESULTS: We identified 22 patients. Median age at the time of EPR was 58 years (range, 36-74). Median tumor diameter was 5.4 cm (range, 1.5-11.2). Primary tumor sites included: uterus, 13; cervix, 7; synchronous uterus/cervix, 1; and synchronous uterus/ovary, 1. The EPR structures were: muscle, 13; nerve, 10; bone, 8; vessel, 5. Complete gross resection with microscopically negative margins (R0 resection) was achieved in 17 patients (77%). There were no perioperative mortalities. Major postoperative complications occurred in 14 patients (64%). The two most common morbidities were pelvic abscesses and peripheral neuropathies. Median follow-up time was 28 months (range, 6-99). The 5-year overall survival (OS) for the entire cohort was 34% (95% CI, 13-57). For the 17 patients who had an R0 resection, the 5-year OS was 48% (95% CI, 19-73). In patients with positive pathologic margins (n=5), the 5-year OS was 0%. CONCLUSION: EPR was associated with prolonged survival when an R0 resection was achieved. The high rate of postoperative complications remains a hallmark of these procedures and properly selected patients should be extensively counseled preoperatively.


Asunto(s)
Exenteración Pélvica/métodos , Neoplasias del Cuello Uterino/cirugía , Neoplasias Uterinas/cirugía , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Exenteración Pélvica/efectos adversos , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias del Cuello Uterino/patología , Neoplasias Uterinas/patología
11.
Gynecol Oncol ; 126(3): 346-50, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22555107

RESUMEN

OBJECTIVE: To describe the surgical technique, complications, and outcomes after anterior pelvic exenteration with total vaginectomy (AETV) for recurrent or persistent genitourinary malignancies. METHODS: We reviewed the medical records of all patients who underwent AETV between 12/2002 and 07/2011. Relevant demographic, clinical, and pathological information was collected. Postoperative complications and rates of readmission and reoperation (up to 180 days after surgery) were examined, and preliminary survival data were obtained. RESULTS: We identified 11 patients who underwent AETV. The median age at the time of the surgery was 55 years (range, 36-71). The median tumor size was 0.9 cm (range, microscopic - 4). Primary tumor sites included: cervix, 6; uterus, 3; vagina, 1; and urethra, 1. Complete surgical resection with negative pathologic margins was achieved in all 11 patients. Major postoperative complications occurred in 4 patients (36%). Six patients (55%) required readmission to the hospital. No operative mortalities were observed, and none of the patients required a re-operation. With a median follow-up after the procedure of 25 months (range, 6-95), none of the patients developed a pelvic recurrence. Ten patients (91%) were alive without evidence of disease and one patient (9%) developed a pancreatic recurrence. CONCLUSION: AETV sparing the rectosigmoid and anus is feasible in highly selected patients with central pelvic recurrences. Compared to previously reported studies on total pelvic exenteration, data from this case series suggest that AETV may be associated with a lower rate of complications without compromising the oncologic outcome, while also preserving rectal function.


Asunto(s)
Adenocarcinoma/cirugía , Carcinoma de Células Escamosas/cirugía , Recurrencia Local de Neoplasia/cirugía , Exenteración Pélvica/métodos , Neoplasias Urogenitales/cirugía , Vagina/cirugía , Adenocarcinoma/patología , Adulto , Anciano , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea , Carcinoma de Células Escamosas/patología , Quimioterapia Adyuvante , Femenino , Humanos , Persona de Mediana Edad , Readmisión del Paciente , Exenteración Pélvica/efectos adversos , Radioterapia Adyuvante , Estudios Retrospectivos , Factores de Tiempo , Neoplasias Urogenitales/patología
12.
Indian J Med Res ; 136(1): 89-97, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22885269

RESUMEN

BACKGROUND & OBJECTIVES: The present study was carried out on stored rice variety PAU 201 in Punjab that was not permitted for milling and public distribution due to the presence of damaged grains at levels exceeding the regulatory limits of 4.75 per cent. The aim of the study was to determine fungal and aflatoxin contamination in the rice samples to assess hazard from the presence of damaged grains. Presence of iron in discoloured rice grains was also assessed. METHODS: Stored samples of paddy of PAU 201 rice variety were collected from six districts of Punjab, milled and analysed for presence of fungal and aflatoxin contamination. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and Prussian blue staining was used to determine fungal spores and presence of iron, respectively. RESULTS: Aflatoxin analysis of rice samples indicated that none exceeded the Food Safety and Standards (Contaminants, Toxins and Residues) Regulations, 2011 tolerance limit of 30 µg/kg and majority of the samples had levels <15 µg/kg. The proportion of damaged grains exceeding the limit of 5 per cent was observed in 85.7 per cent of the samples. SEM and Prussian blue staining and EDX analysis of black tipped and pin point damaged rice grains did not show presence of fungal structures and presence of iron. INTERPRETATION & CONCLUSIONS: The results of the study indicated that the stored rice samples did not pose any health concern with respect to aflatoxin contamination as per the criteria laid down by the Food Safety and Standards Authority of India.


Asunto(s)
Aflatoxinas/análisis , Contaminación de Alimentos/análisis , Microbiología de Alimentos/estadística & datos numéricos , Oryza/química , Oryza/microbiología , Esporas Fúngicas/aislamiento & purificación , Ferrocianuros , Microbiología de Alimentos/normas , India , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X
13.
J Sports Med Phys Fitness ; 52(6): 606-15, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23187323

RESUMEN

AIM: The aim of this study was to establish the effects of core strengthening exercise program on trunk instability in response to vertical jump performances and static balance variables in volleyball players. As a core stabilization program aids in developing a stable spine over the pelvis and improves trunk stability this concept should be incorporated in sports tasks involving jump and reach in those with an unstable spine. METHODS: Forty state level volleyball players with trunk instability were randomly divided into two groups, control ([C] m=10; f=10) and experimental ([E] m=10; f=10). Modified double straight leg lowering test was used to check the degree of trunk instability. Counter movement jump, squat jump, spike jump and block jumps were used to measure jumping abilities and a wobble board test was used to test balance. Pre- and postreadings were noted before and after the nine-week training protocol and statistical data analysis was done using SPSS 16. RESULTS: After nine weeks of core stabilization training, trunk stability (P<0.001), block difference (BD) in block jump (P<0.01) were enhanced significantly comparing to (C) group using independent T test. Effect size Cohen's d score demonstrated better improvement of spike jump (d=0.25) and block jump (d=0.52) in (E) group. Other jumps and static balance were improved but non-significant when compared between groups. CONCLUSION: Nine-week strategic core strengthening exercise program increases trunk stability and in turn improves block difference (vertical jump parameter).


Asunto(s)
Rendimiento Atlético/fisiología , Ejercicio Físico/fisiología , Pierna/fisiología , Movimiento/fisiología , Fuerza Muscular/fisiología , Equilibrio Postural/fisiología , Voleibol/fisiología , Fenómenos Biomecánicos , Estudios de Seguimiento , Humanos , Masculino , Factores de Tiempo , Adulto Joven
14.
J Sports Med Phys Fitness ; 52(5): 465-73, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22976732

RESUMEN

AIM: The purpose of this study was to develop a linear regression model to predict treadmill VO2max scores using non-exercise data. METHODS: In this cross sectional study, one hundred twenty college-aged participants (60 male, 60 female, mean age 22.02±2.29 years) voluntarily participated and successfully completed a maximal graded exercise test (GXT) on a motorized treadmill to assess VO2max (mean±SD; 2.05 L·min-¹±1.03 L·min-¹). The maximal treadmill GXT required participants to exercise to volitional fatigue. RESULTS: Relevant non-exercise data included a mean (±SD) perceived functional ability (PFA) score, and physical activity rating (PA-R) score, body surface area (BSA) of 14.6±3.9, 2.97±1..75, 1.66±0.17, respectively. Multiple linear regression generated the following regression equation (R=0.899, R2=0.805, adjusted R2=0.799, SEE=0.426 L·min-¹): VO2max (L/min)=-1.541+1.096 (gender, 1=male, 0=female) +.081 (PFA) +1.084(BSA). Each predictor variable was statistically significant (P<0.05) with beta weights for gender, PFA, BSA, PA-R, and equal to (-0.518), (0.255), (0.228), (0.092), percent body fat (-0.003), respectively. The accuracy of the model was evaluated by conducting a cross-validation analysis (N.=18). CONCLUSION: This study provides a N-EX regression prediction model that yields results and also provide a convenient and efficient tool that estimate VO2max in healthy college-aged participants in India.


Asunto(s)
Consumo de Oxígeno/fisiología , Estudios Transversales , Prueba de Esfuerzo , Femenino , Humanos , India , Modelos Lineales , Masculino , Modelos Biológicos , Modelos Estadísticos , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Adulto Joven
16.
J Geophys Res Space Phys ; 127(2): e2021JA029298, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35864842

RESUMEN

Loss mechanisms act independently or in unison to drive rapid loss of electrons in the radiation belts. Electrons may be lost by precipitation into the Earth's atmosphere, or through the magnetopause into interplanetary space-a process known as magnetopause shadowing. While magnetopause shadowing is known to produce dropouts in electron flux, it is unclear if shadowing continues to remove particles in tandem with electron acceleration processes, limiting the overall flux increase. We investigated the contribution of shadowing to overall radiation belt fluxes throughout a geomagnetic storm starting on the 7 September 2017. We use new, multimission phase space density calculations to decipher electron dynamics during each storm phase and identify features of magnetopause shadowing during both the net-loss and the net-acceleration storm phases on sub-hour time scales. We also highlight two distinct types of shadowing; "direct," where electrons are lost as their orbit intersects the magnetopause, and "indirect," where electrons are lost through ULF wave driven radial transport toward the magnetopause boundary.

17.
Sci Rep ; 12(1): 21717, 2022 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-36522393

RESUMEN

Chorus waves play a key role in outer Van Allen electron belt dynamics through cyclotron resonance. Here, we use Van Allen Probes data to reveal a new and distinct population of intense chorus waves excited in the heart of the radiation belt during the main phase of geomagnetic storms. The power of the waves is typically ~ 2-3 orders of magnitude greater than pre-storm levels, and are generated when fluxes of ~ 10-100 keV electrons approach or exceed the Kennel-Petschek limit. These intense chorus waves rapidly scatter electrons into the loss cone, capping the electron flux to a value close to the limit predicted by Kennel and Petschek over 50 years ago. Our results are crucial for understanding the limits to radiation belt fluxes, with accurate models likely requiring the inclusion of this chorus wave-driven flux-limiting process, that is independent of the acceleration mechanism or source responsible for enhancing the flux.


Asunto(s)
Gastrópodos , Corazón , Animales , Ciclotrones , Aceleración , Electrones
18.
Clin Exp Rheumatol ; 29(2): 223-30, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21504660

RESUMEN

OBJECTIVES: To evaluate an Ankylosing Spondylitis-specific Arthritis Self-Efficacy Scale (ASES-AS) United Kingdom (UK) secondary care population. METHODS: The ASES-AS is based on the 8-item ASES with minor alterations in phraseology. Patients from ten secondary care rheumatology centres across England were asked to complete a postal questionnaire concerning sociodemographic and clinical characteristics: Bath AS Functional Index (BASFI), Bath AS Disease Activity Index (BASDAI), numerical pain rating scale (NRS), Hospital Anxiety and Depression Scale (HADS), Short Form 36 (SF-36), Evaluation of AS Quality of Life questionnaire (EASi-QoL) and ASES-AS. Respondents received repeat questionnaires at 2 weeks and 6 months including health transition questions assessing change in AS-specific and general health. The ASES-AS was assessed for data quality, reliability, validity, and responsiveness. RESULTS: Response rate was 64% (n=612), 72% (n=438) were male, mean age 50.8yrs (SD 12.2 yrs), mean disease duration 17.3 yrs (SD 11.7 yrs) and mean symptom duration 22.4 yrs (SD 12.4 yrs). Missing data for each item/total score range was 0.7%-3.1%. Item-total correlations range was 0.66 to 0.83. Cronbach's alpha was 0.93 and test-retest reliability (intraclass correlation coefficient) 0.77. A priori hypothesised associations between ASAS-AS and disease status measures were supported. Social variables potentially related to self-efficacy demonstrated evidence of convergent validity (employment p<0.001, educational level p<0.005). A Modified Standard Response Mean (MSRM) of 0.44 and 0.26 in AS-specific and general health respectively at 6 months indicates moderate responsiveness. CONCLUSIONS: ASES-AS has good evidence supporting its application as an AS-specific self-efficacy measure in research including clinical trials at a group level.


Asunto(s)
Autoeficacia , Índice de Severidad de la Enfermedad , Espondilitis Anquilosante/fisiopatología , Espondilitis Anquilosante/psicología , Encuestas y Cuestionarios/normas , Actividades Cotidianas , Adulto , Artritis , Estudios Transversales , Femenino , Estado de Salud , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Servicios Postales , Calidad de Vida , Reproducibilidad de los Resultados , Reino Unido
19.
Epidemiol Infect ; 138(12): 1695-703, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20334726

RESUMEN

One of the largest reported campylobacteriosis outbreaks in Canada occurred in June 2007 in British Columbia, associated with a mountain bike race that took place in muddy conditions. A retrospective cohort study was conducted and environmental samples were collected and tested. There were 537 racers included in the study and 225 racers (42%) reported diarrhoeal illness after the race. C. jejuni clinical isolates (n=14) were found to be identical by multi-locus sequence typing. Although univariate analysis suggested water consumption and mud exposure as significant risk factors, multivariate analysis revealed that on direct ingestion mud was significantly associated with illness (OR 4·08, 95% CI 2·03-8·21). Contaminated mud was thus the most likely source of Campylobacter infection. We identified other unpublished reports of outbreaks associated with bike races in rainy or muddy conditions; these underscore the importance of educating racers and raising public awareness of the risks of mud ingestion.


Asunto(s)
Infecciones por Campylobacter/epidemiología , Campylobacter jejuni/aislamiento & purificación , Brotes de Enfermedades , Ingestión de Alimentos , Suelo , Técnicas de Tipificación Bacteriana , Colombia Británica/epidemiología , Infecciones por Campylobacter/microbiología , Campylobacter jejuni/clasificación , Campylobacter jejuni/genética , Análisis por Conglomerados , Estudios de Cohortes , Dermatoglifia del ADN , ADN Bacteriano/química , ADN Bacteriano/genética , Diarrea/epidemiología , Diarrea/microbiología , Humanos , Estudios Retrospectivos , Análisis de Secuencia de ADN , Deportes
20.
Med Phys ; 36(6): 2324-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19610321

RESUMEN

In this Letter the authors introduce a wide-field transmission ultrasound approach to breast imaging based on the use of a large area acousto-optic (AO) sensor. Accompanied by a suitable acoustic source, such a detector could be mounted on a traditional mammography system and provide a mammographylike ultrasound projection image of the compressed breast in registration with the x-ray mammogram. The authors call the approach acoustography. The hope is that this additional information could improve the sensitivity and specificity of screening mammography. The AO sensor converts ultrasound directly into a visual image by virtue of the acousto-optic effect of the liquid crystal layer contained in the AO sensor. The image is captured with a digital video camera for processing, analysis, and storage. In this Letter, the authors perform a geometrical resolution analysis and also present images of a multimodality breast phantom imaged with both mammography and acoustography to demonstrate the feasibility of the approach. The geometric resolution analysis suggests that the technique could readily detect tumors of diameter of 3 mm using 8.5 MHz ultrasound, with smaller tumors detectable with higher frequency ultrasound, though depth penetration might then become a limiting factor. The preliminary phantom images show high contrast and compare favorably to digital mammograms of the same phantom. The authors have introduced and established, through phantom imaging, the feasibility of a full-field transmission ultrasound detector for breast imaging based on the use of a large area AO sensor. Of course variations in attenuation of connective, glandular, and fatty tissues will lead to images with more cluttered anatomical background than those of the phantom imaged here. Acoustic coupling to the mammographically compressed breast, particularly at the margins, will also have to be addressed.


Asunto(s)
Acústica/instrumentación , Diagnóstico por Imagen de Elasticidad/instrumentación , Dispositivos Ópticos , Transductores , Ultrasonografía Mamaria/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Fantasmas de Imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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