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1.
Br J Surg ; 108(3): 244-255, 2021 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-33793723

RESUMEN

BACKGROUND: A variety of endovascular and open surgical interventions exist to treat great saphenous vein reflux. However, comparisons of treatment outcomes have been inconsistent. METHODS: A systematic review and network meta-analysis of RCTs was performed to compare rates of incomplete stripping or non-occlusion of the great saphenous vein with or without reflux (anatomical failure) at early, mid- and long-term follow-up; and secondary outcomes (reintervention and clinical recurrence) among intervention groups. The surface under the cumulative ranking curve (SUCRA) method was used to estimate the probability of the intervention with the lowest anatomical failure rates. RESULTS: Some 72 RCTs were included. Comparisons of endothermal techniques with open surgery were mostly not significantly different, except for endovenous laser ablation (EVLA), which had higher long-term anatomical failure rates (pooled risk ratio (RR) 1.87, 95 per cent c.i. 1.14 to 3.07). Mechanochemical ablation had higher anatomical failure rates than radiofrequency ablation (RFA) (pooled RR 2.77, 1.38 to 5.53), and cyanoacrylate closure (CAC) had a RR 0.56 (0.34 to 0.93) times lower than either RFA or EVLA at the early term. Ultrasound-guided foam sclerotherapy had a higher risk of anatomical failure and reintervention than open surgery, with the lowest SUCRA value, and CAC was ranked first, third and first for best intervention for anatomical failure at early, mid and long term respectively. However, clinical recurrence rates were not significantly different between all comparisons. CONCLUSION: Mechanochemical ablation and ultrasound-guided foam sclerotherapy performed poorly, with higher anatomical failure rates in the long term. The other treatment modalities had similar rates of anatomical failure in the short and mid term.


Asunto(s)
Vena Safena/cirugía , Insuficiencia Venosa/terapia , Cianoacrilatos , Humanos , Terapia por Láser , Metaanálisis en Red , Ablación por Radiofrecuencia , Ensayos Clínicos Controlados Aleatorios como Asunto , Escleroterapia , Adhesivos Tisulares
2.
BMC Neurol ; 21(1): 112, 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33706706

RESUMEN

BACKGROUND: The retinal and cerebral microvasculature share similar embryological origins and physiological characteristics. Improved imaging technologies provide opportunistic non-invasive assessment of retinal microvascular parameters (RMPs) against cognitive outcomes. We evaluated baseline measures for associations between RMPs and mild cognitive impairment (MCI) from participants of the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA). METHODS: RMPs (central retinal arteriolar / venular equivalents, arteriole to venular ratio, fractal dimension and tortuosity) were measured from optic disc centred fundus images and analysed using semi-automated software. Associations between RMPs and MCI were assessed by multivariable logistic regression with adjustment for potential confounders including age, sex, alcohol consumption, smoking status, educational attainment, physical activity, cardiovascular disease (CVD), hypertension, mean arterial blood pressure, triglycerides, diabetes, body mass index, and high density lipoprotein levels. P < 0.05 was considered statistically significant. RESULTS: Data were available for 1431 participants, of which 156 (10.9%) were classified with MCI defined by a Montreal Cognitive Assessment (MoCA) score ≤ 26, with subjective cognitive decline, in the absence of depression or problems with activities of daily living. Participants had a mean age of 62.4 ± 8.5 yrs. and 52% were female. As expected, individuals with MCI had a lower MoCA score than those without (23.5 ± 2.6 versus 26.3 ± 2.7, respectively), were more likely to be female, have a lower level of educational attainment, be less physically active, more likely to have CVD, have higher levels of triglycerides and lower levels of high density lipoprotein. No significant associations between RMPs and MCI were detected in unadjusted, minimally adjusted or fully adjusted regression models or subsequent sensitivity analyses. CONCLUSION: Previous studies have reported both increased retinal venular calibre and reduced fractal dimension in association with mild cognitive impairment. Our study failed to detect any associations between RMPs and those individuals at an early stage of cognitive loss in an older community-based cohort.


Asunto(s)
Disfunción Cognitiva/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Anciano , Envejecimiento/patología , Disfunción Cognitiva/complicaciones , Estudios de Cohortes , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Estudios Longitudinales , Masculino , Microvasos/diagnóstico por imagen , Microvasos/patología , Persona de Mediana Edad , Irlanda del Norte , Retina/diagnóstico por imagen , Retina/patología
3.
BMC Geriatr ; 21(1): 62, 2021 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-33446119

RESUMEN

INTRODUCTION: The retina shares similar anatomical and physiological features with the brain and subtle variations in retinal microvascular parameters (RMPs) may reflect similar vascular variation in the brain. The aim of this study was to assess associations between RMPs and measures of depression in the Northern Ireland Cohort for the Longitudinal Study of Ageing. METHODS: RMPs (arteriolar and venular caliber, fractal dimension and tortuosity) were measured from optic disc centred fundus images using semi-automated software. Depression was characterised by the Centre for Epidemiologic Studies Depression Scale (CES-D) in the absence of mild cognitive impairment or use of anti-depressive medications. Associations between depression and RMPs were assessed by regression analyses with adjustment for potential confounders. RESULTS: Data were available for 1376 participants of which 113 (8.2%) and 1263 (91.8%) were classified with and without depression. Participants had a mean age of 62.0 ± 8.4 yrs., 52% were female, and 8% were smokers. Individuals with depression had a higher CES-D score than those without (22.0 ± 6.2 versus 4.4 ± 3.9). Lower values of arteriolar tortuosity were significantly associated with depression, before and after adjustment for potential confounders (odds ratio = 0.79; 95% confidence intervals: 0.65, 0.96; P = 0.02). CONCLUSION: Decreased retinal arteriolar tortuosity, a measure of the complexity of the retinal microvasculature was associated with depression in older adults independent of potential confounding factors. Retinal measures may offer opportunistic assessment of microvascular health associated with outcomes of depression.


Asunto(s)
Depresión , Vasos Retinianos , Anciano , Envejecimiento , Depresión/diagnóstico , Depresión/epidemiología , Femenino , Humanos , Estudios Longitudinales , Masculino , Irlanda del Norte/epidemiología , Retina , Vasos Retinianos/diagnóstico por imagen , Factores de Riesgo
4.
Clin Endocrinol (Oxf) ; 87(4): 327-335, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28656591

RESUMEN

BACKGROUND: The relationship between bone health and adiposity and how it may be affected in people with chronic metabolic conditions is complex. METHODS: Seventeen women with type 1 diabetes mellitus (T1DM) and nine age-matched healthy women with a median age of 22.6 years (range, 17.4, 23.8) were studied by 3T MRI and MR spectroscopy to assess abdominal adiposity, tibial bone microarchitecture and vertebral bone marrow adiposity (BMA). Additional measures included DXA-based assessments of total body (TB), femoral neck (FN) and lumbar spine (LS) bone mineral density (BMD) and fat mass (FM). RESULTS: Although women with T1DM had similar BMI and BMA to the controls, they had higher visceral and subcutaneous adiposity on MRI (P<.05) and total body FM by DXA (P=.03). Overall, in the whole cohort, a clear inverse association was evident between BMA and BMD at all sites (P<.05). These associations remained significant after adjusting for age, BMI, FM and abdominal adiposity. In addition, visceral adiposity, but not subcutaneous adiposity, showed a positive association with BMA (r, .4, P=.03), and a negative association with total body BMD (r, .5, P=.02). Apparent trabecular separation as assessed by MRI showed an inverse association to total body BMD by DXA (r, -.4, P=.04). CONCLUSION: Irrespective of the presence of an underlying metabolic condition, young women display a negative relationship between MRI-measured BMA and DXA-based assessment of BMD. Furthermore, an association between BMA and visceral adiposity supports the notion of a common origin of these two fat depots.


Asunto(s)
Adiposidad/fisiología , Densidad Ósea/fisiología , Diabetes Mellitus Tipo 1/metabolismo , Cuello Femoral/metabolismo , Vértebras Lumbares/metabolismo , Adiposidad/genética , Adolescente , Adulto , Densidad Ósea/genética , Diabetes Mellitus Tipo 1/patología , Femenino , Humanos , Imagen por Resonancia Magnética , Espectrometría de Masas , Adulto Joven
5.
Diabet Med ; 34(7): 1005-1008, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28375568

RESUMEN

BACKGROUND: Type 4 renal tubular acidosis causes hyperkalaemia, for which diabetes and medications commonly used in this patient group are aetiological factors. Here we describe the novel use of fludrocortisone in this difficult condition. CASE REPORT: A 55-year-old woman with complex co-morbidities, including Type 2 diabetes (HbA1c 37 mmol/mol 5.5%), was admitted with renal failure. Bloods on admission: eGFR 25 ml/min, creatinine 184 ?mol/L, urea 35.9 mmol/L, sodium 128 mmol/L, potassium 5.6 mmol/L, bicarbonate 15 mmol/L, and albumin 30 g/L. Her admission was prolonged, complicated by hospital-acquired sepsis (lower respiratory tract, urinary tract, and infected leg ulcers), poor venous access and severe depression. She had recurrent hyperkalaemia and deteriorating renal function, from presumed Type 4 renal tubular acidosis and excessive fluid losses from leg ulcers. Her renal function recurrently deteriorated, despite conventional treatment methods. After 69 days, she was commenced on fludrocortisone 50 mcg/day. Her renal function and serum potassium stabilized and she was discharged with potassium 4.3 mmol/L, eGFR 42 ml/min, and bicarbonate 23 mmol/L. She has remained stable on this treatment, without requiring further hospital admission for over 6 months, with eGFR 40 ml/min, and potassium 5.5 mmol/L, and albumin 26 g/L. CONCLUSION: This woman was presumed to have Type 4 renal tubular acidosis and recurrent hyperkalaemia due to renal insufficiency, in the context of underlying diabetes and chronic kidney disease, which was poorly responsive to conventional management. There is limited evidence for using fludrocortisone in this setting. Our case suggests that fludrocortisone might offer a novel therapeutic strategy when conventional management is not working.


Asunto(s)
Acidosis Tubular Renal/tratamiento farmacológico , Antiinflamatorios/uso terapéutico , Fludrocortisona/uso terapéutico , Hiperpotasemia/prevención & control , Riñón/efectos de los fármacos , Acidosis Tubular Renal/epidemiología , Acidosis Tubular Renal/etiología , Acidosis Tubular Renal/fisiopatología , Comorbilidad , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Humanos , Hiperpotasemia/epidemiología , Hiperpotasemia/etiología , Riñón/inmunología , Riñón/fisiopatología , Fallo Renal Crónico/epidemiología , Fallo Renal Crónico/inmunología , Fallo Renal Crónico/fisiopatología , Persona de Mediana Edad , Prevención Secundaria , Resultado del Tratamiento
6.
BMC Med Educ ; 16: 88, 2016 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-26956764

RESUMEN

BACKGROUND: Evidence suggests that junior doctors lack the confidence and skills to manage acute/inpatient diabetes. We investigated the impact of the introduction of a "Diabetes Acute Care Day" on undergraduate medical students' knowledge and confidence in acute/inpatient diabetes. METHODS: Participants attended four short lectures on the basics of diabetes, diabetic emergencies, inpatient diabetes management and peri-operative/procedure care followed by case-based learning tutorials on diabetic ketoacidosis (DKA), hyperosmolar hyperglycaemic state (HHS) and hypoglycaemia using capillary blood glucose charts to interpret and practice subsequent insulin prescription and adjustment. Participants were asked to complete multiple-choice questions and confidence questionnaires using a visual analogue score pre and post participation. RESULTS: One hundred forty-four students completed the pre-course survey and 196 completed the post-course survey. Mean confidence using a visual analogue score increased in all areas with a mean at baseline of 46.9 mm rising to 71.2 mm post-participation (p < 0.001). The largest increases were in the management of HHS, patients on subcutaneous and intravenous insulin and perioperative/procedure care. The mean mark obtained in the pre-test multiple choice questions (MCQs) was 2.72 (27.2 %) and increased to 4.74 (47.4 %) on the post-score MCQs (p < 0.001). 56.9 % of participants answered all 10 pre-test MCQs with the mean number of questions answered = 4.71 rising to 82.0 % of students answered all ten questions and the mean number of questions answered = 9.56 in the post-test MCQs. CONCLUSIONS: An intensive "Diabetes Acute Care Day" consisting of themed live lectures and case-based learning tutorials is an effective way to increase medical students' knowledge and confidence in acute/inpatient diabetes. Further development and evaluation of this educational intervention is required to assess the impact of on patient care in the clinical setting post graduation.


Asunto(s)
Competencia Clínica , Diabetes Mellitus/terapia , Educación Médica/métodos , Competencia Clínica/normas , Curriculum , Evaluación Educacional , Humanos , Proyectos Piloto , Estudiantes de Medicina
7.
Scott Med J ; 58(2): e7-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23728768

RESUMEN

A 54-year-old lady being investigated at the medical clinic for back pain and weight loss, was diagnosed with idiopathic retroperitoneal fibrosis on the basis of CT imaging, biopsy findings and absence of known secondary causes. After lengthy discussions with the patient during several clinic visits she declined the use of corticosteroid treatment due to concerns for the potential side effects. Serial monitoring of inflammatory markers and interval imaging suggested a spontaneous remission in the inflammatory process. We describe the case and discuss the management of retroperitoneal fibrosis.


Asunto(s)
Fibrosis Retroperitoneal , Dolor de Espalda/etiología , Femenino , Humanos , Hidronefrosis/etiología , Persona de Mediana Edad , Remisión Espontánea , Fibrosis Retroperitoneal/complicaciones , Fibrosis Retroperitoneal/terapia
8.
Biofilm ; 5: 100098, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36588982

RESUMEN

Purple non-sulphur bacteria (PNSB) are of interest for biorefinery applications to create biomolecules, but their production cost is expensive due to substrate and biomass separation costs. This research has utilized fuel synthesis wastewater (FSW) as a low-cost carbon-rich substrate to produce single-cell protein (SCP) and examines PNSB biofilm formation using this substrate to achieve a more efficient biomass-liquid separation. In this study, PNSB were grown in Ca, Mg, S, P, and N-deficient media using green shade as biofilm support material. Among these nutrient conditions, only N-deficient and control (nutrient-sufficient) conditions showed biofilm formation. Although total biomass growth of the control was 1.5 times that of the N-deficient condition and highest overall, the total biofilm-biomass in the N-deficient condition was 2.5 times greater than the control, comprising 49% of total biomass produced. Total protein content was similar between these four biomass samples, ranging from 35.0 ± 0.2% to 37.2 ± 0.0%. The highest protein content of 44.7 ± 1.3% occurred in the Mg-deficient condition (suspended biomass only) but suffered from a low growth rate. Overall, nutrient sufficient conditions are optimal for overall protein productivity and dominated by suspended growth, but where fixed growth systems are desired for cost-effective harvesting, N-deficient conditions provide an effective means to maximize biofilm production without sacrificing protein content.

9.
Eur Phys J E Soft Matter ; 35(8): 74, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22898940

RESUMEN

The relationship between bistable surface anchoring and the pitch jump process is examined for a planar cholesteric liquid crystal. Introducing a high-order, azimuthal surface anchoring potential into a simple model to describe a cholesteric, we derive an expression for the director twist as the natural pitch of the liquid crystal is allowed to vary. Writing the energy in terms of the surface twist, we are able to determine the twists which minimize the total energy of the system. We demonstrate how a pitch jump is related to an energy exchange from one branch of metastable states to another. We then discuss how the co-existence of energy minima and their associated solution branches may help explain the thermal hysteresis observed experimentally in cholesterics in the neighbourhood of a pitch jump. The presence of a higher-order surface energy term can expand the range of anchoring strengths in which pitch jumps are possible. We also investigate the influence of bidirectional surface anchoring on the behaviour of the total energy. Intermediate quarter-turn pitch jumps can occur, depending on the relative strength of the high-order anchoring term, and these can have a significant effect on the system hysteresis.

10.
Scott Med J ; 57(1): 14-7, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22194405

RESUMEN

In this study we model the impact of introducing outpatient investigation of pulmonary thrombo-embolism (PTE) to the acute medical unit (AMU) using the Pulmonary Embolism Severity Index (PESI) decision rule. Specifically, we ask what proportion of patients requiring imaging could be investigated without admission, and how many bed-days this would save.  We obtained records for all medical patients who had imaging for PTE in a six-month period at a large teaching hospital with a 40-bedded AMU. The patients were categorized into suitability for outpatient investigation using a combination of the PESI rule and practical considerations. Three hundred and fifty-nine separate presentations were identified. From available records, 31 patients (9.2%, 95% confidence interval [CI] 6.6-12.8%) had no contraindications to outpatient management. These patients used a total of 79 bed-days in the six-month period, or 1.1% (95% CI 0.8-1.5%) of the maximum AMU bed occupancy. Around 10% of patients who require imaging for suspected PTE could be triaged to outpatient investigation using the PESI tool. Adopting this method to triage patients of ambulatory care, would have only a modest effect on acute medical bed occupancy, but remains a valid option for motivated patients in the low-risk category.


Asunto(s)
Atención Ambulatoria/métodos , Selección de Paciente , Embolia Pulmonar/diagnóstico , Triaje , Anciano , Técnicas de Apoyo para la Decisión , Femenino , Hospitalización , Humanos , Masculino , Valor Predictivo de las Pruebas , Derivación y Consulta , Reproducibilidad de los Resultados , Estudios Retrospectivos , Medición de Riesgo , Escocia/epidemiología , Índice de Severidad de la Enfermedad
11.
Diabetologia ; 54(2): 334-8, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21103979

RESUMEN

AIMS/HYPOTHESIS: Several studies have provided compelling evidence implicating the Notch signalling pathway in diabetic nephropathy. Co-regulation of Notch signalling pathway genes with GREM1 has recently been demonstrated and several genes involved in the Notch pathway are differentially expressed in kidney biopsies from individuals with diabetic nephropathy. We assessed single-nucleotide polymorphisms (SNPs; n = 42) in four of these key genes (JAG1, HES1, NOTCH3 and ADAM10) for association with diabetic nephropathy using a case-control design. METHODS: Tag SNPs and potentially functional SNPs were genotyped using Sequenom or Taqman technologies in a total of 1371 individuals with type 1 diabetes (668 patients with nephropathy and 703 controls without nephropathy). Patients and controls were white and recruited from the UK and Ireland. Association analyses were performed using PLINK (http://pngu.mgh.harvard.edu/∼purcell/plink/) and haplotype frequencies in patients and controls were compared. Adjustment for multiple testing was performed by permutation testing. RESULTS: In analyses stratified by centre, we identified six SNPs, rs8708 and rs11699674 (JAG1), rs10423702 and rs1548555 (NOTCH3), rs2054096 and rs8027998 (ADAM10) as being associated with diabetic nephropathy before, but not after, adjustment for multiple testing. Haplotype and subgroup analysis according to duration of diabetes also failed to find an association with diabetic nephropathy. CONCLUSIONS/INTERPRETATION: Our results suggest that common variants in JAG1, HES1, NOTCH3 and ADAM10 are not strongly associated with diabetic nephropathy in type 1 diabetes among white individuals. Our findings, however, cannot entirely exclude these genes from involvement in the pathogenesis of diabetic nephropathy.


Asunto(s)
Nefropatías Diabéticas/genética , Receptores Notch/metabolismo , Proteínas ADAM/genética , Proteína ADAM10 , Adolescente , Adulto , Secretasas de la Proteína Precursora del Amiloide/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteínas de Unión al Calcio/genética , Niño , Diabetes Mellitus Tipo 1/genética , Transición Epitelial-Mesenquimal/genética , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Proteínas de Homeodominio/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Proteína Jagged-1 , Masculino , Proteínas de la Membrana/genética , Polimorfismo de Nucleótido Simple/genética , Receptor Notch3 , Receptores Notch/genética , Proteínas Serrate-Jagged , Transducción de Señal/genética , Transducción de Señal/fisiología , Factor de Transcripción HES-1 , Adulto Joven
12.
Clin Epigenetics ; 13(1): 99, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33933144

RESUMEN

BACKGROUND: A subset of individuals with type 1 diabetes mellitus (T1DM) are predisposed to developing diabetic kidney disease (DKD), the most common cause globally of end-stage kidney disease (ESKD). Emerging evidence suggests epigenetic changes in DNA methylation may have a causal role in both T1DM and DKD. The aim of this exploratory investigation was to assess differences in blood-derived DNA methylation patterns between individuals with T1DM-ESKD and individuals with long-duration T1DM but no evidence of kidney disease upon repeated testing to identify potential blood-based biomarkers. Blood-derived DNA from individuals (107 cases, 253 controls and 14 experimental controls) were bisulphite treated before DNA methylation patterns from both groups were generated and analysed using Illumina's Infinium MethylationEPIC BeadChip arrays (n = 862,927 sites). Differentially methylated CpG sites (dmCpGs) were identified (false discovery rate adjusted p ≤ × 10-8 and fold change ± 2) by comparing methylation levels between ESKD cases and T1DM controls at single site resolution. Gene annotation and functionality was investigated to enrich and rank methylated regions associated with ESKD in T1DM. RESULTS: Top-ranked genes within which several dmCpGs were located and supported by functional data with methylation look-ups in other cohorts include: AFF3, ARID5B, CUX1, ELMO1, FKBP5, HDAC4, ITGAL, LY9, PIM1, RUNX3, SEPTIN9 and UPF3A. Top-ranked enrichment pathways included pathways in cancer, TGF-ß signalling and Th17 cell differentiation. CONCLUSIONS: Epigenetic alterations provide a dynamic link between an individual's genetic background and their environmental exposures. This robust evaluation of DNA methylation in carefully phenotyped individuals has identified biomarkers associated with ESKD, revealing several genes and implicated key pathways associated with ESKD in individuals with T1DM.


Asunto(s)
Metilación de ADN/genética , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/complicaciones , Epigénesis Genética/genética , Fallo Renal Crónico/genética , Adulto , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/genética , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/genética , Epigenómica/métodos , Femenino , Humanos , Fallo Renal Crónico/sangre , Fallo Renal Crónico/etiología , Masculino
13.
Diabet Med ; 27(10): 1097-106, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20854376

RESUMEN

Clinical studies in Type 2 diabetes mellitus have shown that the effects of metformin go beyond improving HbA(1c) and include reductions in cardiovascular endpoints. Metformin therapy has been widely used in the treatment of Type 2 diabetes for many years, yet the precise mode of action remains uncertain. It has recently been proposed that metformin-mediated stimulation of hepatic AMP-activated protein kinase (AMPK) underlies the hypoglycaemic effects of metformin. AMPK is a heterotrimeric enzyme that is expressed in many tissues and plays a central role in the regulation of energy homoeostasis. Furthermore, there is increasing evidence that AMPK is implicated in the pathophysiology of cardiovascular and metabolic diseases. The generation of more specific and potent activators of AMPK, however, could have additional metabolic and vascular benefits for patients with Type 2 diabetes.


Asunto(s)
Proteínas Quinasas Activadas por AMP/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada/efectos de los fármacos , Hipoglucemiantes/uso terapéutico , Metformina/farmacología , Humanos , Hipoglucemiantes/farmacología , Metformina/uso terapéutico , Investigación Biomédica Traslacional
15.
Endoscopy ; 42(5): 400-4, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20213591

RESUMEN

BACKGROUND AND AIMS: En bloc resection is preferred for colonic laterally spreading tumors, but is limited to 20 mm with endoscopic mucosal resection (EMR) using normal saline submucosal injection. Our aims were to compare the efficacy and safety of circumferential submucosal incision prior to EMR (CSI-EMR) versus conventional EMR for en bloc resection of artificial lesions 40 x 40 mm in size using submucosal injection of succinylated gelatin in a porcine colon model. SUBJECTS AND METHODS: Two areas of normal rectosigmoid mucosa measuring 40 x 40 mm were marked with soft coagulation for en bloc resection in each of 10 pigs. By alternate allocation, one was removed with conventional snare-based EMR following submucosal injection of succinylated gelatin. The other was circumferentially incised using an insulated-tip knife, followed by submucosal succinylated gelatin injection followed by EMR of the isolated area. All procedures were performed by a single endoscopist with significant experience of EMR but none of endoscopic submucosal dissection (ESD). Euthanasia and colectomy were performed on day 10. Specimens and ex vivo colon resection sites were examined by a specialist gastrointestinal histopathologist blinded to the technique used. RESULTS: En bloc excision rates were 70 % for CSI-EMR vs. 0 % for conventional EMR ( P = 0.016). The median number of resections was 1 (interquartile range, IQR: 1-2) for CSI-EMR vs. 4 (3 - 6) for EMR ( P < 0.001). Mean specimen dimensions were 50 x 43 mm for CSI-EMR vs. 37 x 32 mm for EMR ( P = 0.001). Overall procedure duration (mean +/- SD) was 30.3 +/- 19.8 minutes for CSI-EMR vs. 12.4 +/- 6.8 minutes ( P = 0.003) for EMR. The mean duration of the final 5 CSI-EMRs was 17 minutes, with a statistically significant learning effect R = -0.7, P = 0.025. No perforations or bleeding occurred. All animals were euthanased on day 10. Histologically, CSI-EMR resulted in larger specimens and deeper submucosal resections. CONCLUSIONS: CSI-EMR with submucosal injection of succinylated gelatin is safe and superior to conventional EMR, consistently resulting in en bloc resections larger than 50 x 40 mm. With experience, total procedure duration is comparable.


Asunto(s)
Neoplasias del Colon/cirugía , Colonoscopía/métodos , Disección/métodos , Mucosa Intestinal/cirugía , Animales , Colon , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/patología , Gelatina/administración & dosificación , Inyecciones , Neoplasias Experimentales , Sustitutos del Plasma , Succinatos/administración & dosificación , Porcinos , Resultado del Tratamiento
16.
Environ Technol ; 41(19): 2533-2545, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30681405

RESUMEN

Forward osmosis (FO) has received widespread recognition in the past decade due to its potential low energy production of water. This study presents a new model analysis for predicting the water flux in FO systems when inorganic-based draw solutions are used under variable experimental conditions for using a laboratory scale cross-flow single cell unit. The new model accounts for the adverse impact of concentration polarization (both ICP and ECP) incorporating the water activity by Pitzer to calculate the bulk osmotic pressures. Using the water activity provides a better correlation of experimental data than the classical van't Hoff equation. The nonlinear model also gave a better estimate for the structural parameter factor (S) of the membrane in its solution. Furthermore, the temperature and concentration of both the draw and feed solutions played a significant role in increasing the water flux, which could be interpreted in terms of the mass transfer coefficient representing ECP; a factor sensitive to the hydraulics of the system. The model provides greatly improved correlations for the experimental water fluxes.


Asunto(s)
Membranas Artificiales , Purificación del Agua , Ósmosis , Presión Osmótica , Agua
17.
PLoS One ; 15(1): e0227175, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31923188

RESUMEN

BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is associated with an increased risk of myocardial infarction and stroke but it remains unclear how to identify microvascular changes in this population. OBJECTIVES: We hypothesized that simple non-mydriatic retinal photography is feasible and can be used to assess microvascular damage in COPD. METHODS: Novel Vascular Manifestations of COPD was a prospective study comparing smokers with and without COPD, matched for age. Non-mydriatic, retinal fundus photographs were assessed using semi-automated software. RESULTS: Retinal images from 24 COPD and 22 control participants were compared. Cases were of similar age to controls (65.2 vs. 63.1 years, p = 0.38), had significantly lower Forced Expiratory Volume in one second (FEV1) (53.4 vs 100.1% predicted; p < 0.001) and smoked more than controls (41.7 vs. 29.6 pack years; p = 0.04). COPD participants had wider mean arteriolar (155.6 ±15 uM vs. controls [142.2 ± 12 uM]; p = 0.002) and venular diameters (216.8 ±20.7 uM vs. [201.3± 19.1 uM]; p = 0.012). Differences in retinal vessel caliber were independent of confounders, odds ratios (OR) = 1.08 (95% confidence intervals [CI] = 1.02, 1.13; p = 0.007) and OR = 1.05 (CI = 1.01, 1.09; p = 0.011) per uM increase in arteriolar and venular diameter respectively. FEV1 remained significantly associated with retinal vessel dilatation r = -0.39 (p = 0.02). CONCLUSIONS: Non-mydriatic retinal imaging is easily facilitated. We found significant arteriole and venous dilation in COPD compared to age-matched smokers without COPD associated with lung function independent of standard cardiovascular risk factors. Retinal microvascular changes are known to be strongly associated with future vascular events and retinal photography offers potential to identify this risk. TRIAL REGISTRATION: clinicaltrials.gov NCT02060292.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microvasos/diagnóstico por imagen , Fotomicrografía/métodos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedades de la Retina/diagnóstico por imagen , Enfermedades de la Retina/etiología , Vasos Retinianos/diagnóstico por imagen , Adulto , Anciano , Estudios de Casos y Controles , Estudios de Factibilidad , Femenino , Fondo de Ojo , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Vasos Retinianos/patología , Fumadores , Fumar/efectos adversos
18.
Science ; 179(4068): 71-4, 1973 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-17731632

RESUMEN

Lunar samples 60017,4 and 63335,14 are composed of microbreccias and devitrified glass. These components are predominantly anorthositic, with the exception of a cryptocrystalline clast found in the microbreccia portion of 63335,14 which contains 2.7 percent potassium oxide and 66.7 percent silicon dioxide. The samples have been subjected to extreme shock and thermal metamorphism. The parent materials of the microbreccias include both a coarse-grained anorthosite and a fine-grained subophitic anorthositic gabbro.

19.
Science ; 167(3918): 635-8, 1970 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-17781526

RESUMEN

All phases in a thin section of sample 10022 have been analyzed by electron microprobe. Augite grains show strong iron enrichment in the outer 15 to 20 microns. Pigeonite cores occur within augite grains. The plagioclase has an anorthite content of between 73 and 81 mole percent and is high in Si and low in Al compared to stoichiometric feldspar. Residual phases include microcrystalline Fe-rich "pyroxene," plagioclase, K-rich alkali feldspar, silica, and rare areas rich in P and Zr with concentrations of Ba, Y, and rare earth elements. The density, viscosity, and crystallization history of the lava of sample 10022 are discussed.

20.
Colorectal Dis ; 11(3): 291-5, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18477019

RESUMEN

OBJECTIVE: There is little information on the impact of the colorectal multi-disciplinary team (MDT) in the United Kingdom. Our single operator presented his patients before and after the inception of an MDT meeting in June 2002. The aim of this study was to assess the effect of this on his patients' survival, and trends in the use of adjuvant chemotherapy. METHOD: Data were collected on all patients (n = 310) undergoing colectomy for colorectal cancer by one surgeon. Excluding patients with Dukes A stage, the pre-MDT cohort from January 1997 to May 2002 was 176 and the post-MDT cohort from June 2002 to December 2005 was 134. Three-year survival rates were calculated using Kaplan-Meier life table analysis. Prognostic factors were analysed using Cox-proportional hazard regression, and chemotherapy data analysed using the chi-squared test. Independent prognostic indicators of chemotherapy prescription were examined using binary logistic testing. RESULTS: MDT status was shown to be an independent predictor of survival on hazard regression analysis (P = 0.044). A significantly greater number of patients were prescribed adjuvant chemotherapy in the post-MDT cohort (P = 0.0002). MDT status was shown to be a significant prognostic indicator of chemotherapy prescription (P < 0.0001). Three-year survival for Dukes C patients was 58% in the pre-MDT group, and 66% in the post-MDT group (P = 0.023). CONCLUSION: There was a significant increase in patients undergoing adjuvant postoperative chemotherapy after the inception of the MDT. This was associated with a significant survival benefit in patients with Dukes C disease. The data suggest that the MDT process has resulted in an increase in the prescription of adjuvant chemotherapy, with 3-year survival being greater after its inception.


Asunto(s)
Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/terapia , Comunicación Interdisciplinaria , Grupo de Atención al Paciente/organización & administración , Anciano , Quimioterapia Adyuvante , Distribución de Chi-Cuadrado , Colectomía/métodos , Neoplasias Colorrectales/patología , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Probabilidad , Pronóstico , Modelos de Riesgos Proporcionales , Radioterapia Adyuvante , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Reino Unido
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