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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.
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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.
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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 , MasculinoRESUMEN
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.
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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 TisularesRESUMEN
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.
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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/patologíaRESUMEN
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.
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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 RiesgoRESUMEN
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.
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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 adversosRESUMEN
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.
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Membranas Artificiales , Purificación del Agua , Ósmosis , Presión Osmótica , AguaRESUMEN
BACKGROUND: Retinal vessel abnormalities are associated with cardiovascular disease risk. Widening of retinal venules is associated with increased risk of stroke while narrowing of retinal arterioles independently predicts incident hypertension, coronary heart disease and diabetes. Dietary factors are known to play an important role in cardiovascular health. However, few studies have examined the association between dietary patterns (DPs) and retinal microvascular health. OBJECTIVE: To examine the association between 'a posteriori'-derived DPs and retinal vascular caliber (RVC) in older women with a restricted lifestyle. METHODS: This was a cross-sectional study of 1233 participants (mean age: 76.3 years) from the Irish Nun Eye Study (INES). Computer-assisted software was used to measure RVC from digital eye images using standardized protocols. Dietary intake was assessed using a food frequency questionnaire (FFQ). DP analysis was performed using principal component analysis from completed FFQs. Regression models were used to assess associations between DPs and retinal vessel diameters, adjusting for age, body mass index, refraction, hypertension, diabetes mellitus, ischemic heart disease, cerebrovascular accident and fellow eye RVC. RESULTS: Two DPs were identified: a 'healthy' pattern with high factor loadings for fruit, vegetables, wholegrains and oily fish and an 'unhealthy' pattern with high factor loadings for sugar and sweets, chips, high fat dairy products and French fries. Adjusted linear regression analysis revealed that those who adhered most closely to the unhealthy DP had wider central retinal venular equivalent (CRVE) (p=0.03) and narrower central retinal arteriolar equivalent (CRAE) (p=0.01) compared to the least unhealthy DP. No independent relationship was observed between the healthy DP and RVC. CONCLUSION: In this cohort of older women with a restricted lifestyle, an unhealthy DP was independently associated with an unfavorable retinal profile, namely a widening of retinal venules and narrowing of retinal arterioles.
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Fenómenos Fisiológicos Cardiovasculares , Dieta Saludable , Preferencias Alimentarias , Estado de Salud , Vasos Retinianos/fisiología , Anciano , Anciano de 80 o más Años , Arteriolas/fisiología , Índice de Masa Corporal , Estudios de Cohortes , Estudios Transversales , Productos Lácteos/efectos adversos , Femenino , Frutas/efectos adversos , Humanos , Hipertensión/fisiopatología , Irlanda , Persona de Mediana Edad , Monjas , Carne Roja/efectos adversos , Factores de Riesgo , Encuestas y Cuestionarios , Verduras/efectos adversos , Vénulas/fisiologíaRESUMEN
We consider a shallow rectangular well of nematic liquid crystal subject to weak anchoring on the sides of the well. By considering weak anchoring instead of infinitely strong anchoring, we are able to analyze nematic equilibria in the well without the need to exclude point defects at the corners, as done in previous work in the area. For relatively weak anchoring, we are able to derive analytic expressions for the director alignment angle in terms of an infinite series of modes, involving roots of a transcendental equation. The analytic forms of the director configuration are then used to calculate critical anchoring strengths at which uniform and distorted director structures exchange stability. We also consider the asymptotic behavior of the director structure and energy for very strong anchoring. We show that in both cases-for the transitions from uniform to distorted states and the limit of infinitely strong anchoring-the approximate analytic expansions agree very well with corresponding numerical calculations of the full model.
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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.
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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 JovenRESUMEN
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.
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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 TratamientoRESUMEN
Herein we detail the cases of three patients transferred on veno-arterial extracorporeal membrane oxygenation (VA ECMO) from a tertiary referral hospital to an ECMO centre. We highlight the benefits of such a transfer and offer this as a model of care for unwell patients likely to require a prolonged period of ECMO support.
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Oxigenación por Membrana Extracorpórea/métodos , Transferencia de Pacientes , Adulto , Australia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Centros de Atención Terciaria , Factores de TiempoRESUMEN
We demonstrate that a compact manometer experiment allows direct observation of a delay to the classical electric-field-induced Freedericksz transition produced by flow in a highly dispersive nematic liquid crystal layer. The Ericksen-Leslie equations are used to show that a flow aligning torque generated in the nematic layer under Poiseuille flow competes with the orthogonal electric-field reorientation torque. This model fully reproduces the experimental results using only self-consistently determined viscosity values, and predicts a more generally applicable expression for the dependence of the delay E(c)âsqrt[ζ/Δχ(e)] on the shear rate ζ and on the electric susceptibility anisotropy Δχ(e).
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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.
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Competencia Clínica , Diabetes Mellitus/terapia , Educación Médica/métodos , Competencia Clínica/normas , Curriculum , Evaluación Educacional , Humanos , Proyectos Piloto , Estudiantes de MedicinaRESUMEN
STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To identify whether an in vivo correlation exists between lumbar spinal subtype (LSS) and lumbar disc degeneration (LDD) in young adults. SUMMARY OF BACKGROUND DATA: Lumbar disc degeneration has largely been ascribed to biomechanical and structural alterations to the disc, which are attributed to aging and pathological physical loading. Sagittal alignment in the asymptomatic spine has also been considered. A biomechanical study by Roussouly and Pinheiro-Franco proposed level-specific patterns in LDD. To date, no in vivo correlation between the LSS and LDD has been established. METHODS: The authors screened 608 consecutive patients over 5.3 years. Lumbar spinal subtype and pelvic parameters were collected from standing lumbar radiographs and were categorized using the classification of Roussouly and Pinheiro-Franco. Lumbar disc degeneration at all lumbar intervertebral levels was classified using criteria of Pfirrmann et al. A stratified disc degeneration score was derived for each patient. Lumbar disc degeneration in type I, II, and IV LSS was compared using chi-square test. Pelvic incidence was correlated with stratified disc degeneration score using Spearman R, to determine whether a high PI was protective against LDD. Statistical significance was accepted at p < .05. RESULTS: A total of 139 patients were included, with 91 females and a mean age of 32.6 years (range, 13-49 years). For LSS grades I to IV, there were 10 (7.3%), 43 (30.9%), 50 (35.9%), and 36 (25.9%) patients, respectively. The proportion of high-grade (Pfirrmann grades IV and V) LDD increased distally toward the lower intervertebral levels, affecting 2.88%, 2.9%, 5%, 9.4%, 33.1%, and 54% of discs at each sequential lumbar level from T12-L1 to L5-S1, respectively. Age but not gender was statistically significant for higher-grade LDD (p < .0001 and p = .442, respectively). Pelvic incidence across all LSS grades was not significantly correlated with stratified disc degeneration score (Spearman R = 0.0933; p = .335). No LSS (type I-IV) reached statistical significance for a specific pattern of LDD. CONCLUSIONS: In this study, LSS was not statistically significantly correlated with LDD, nor was a high pelvic incidence protective against LDD.
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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.
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Fibrosis Retroperitoneal , Dolor de Espalda/etiología , Femenino , Humanos , Hidronefrosis/etiología , Persona de Mediana Edad , Remisión Espontánea , Fibrosis Retroperitoneal/complicaciones , Fibrosis Retroperitoneal/terapiaRESUMEN
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.
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Hypertensive disorders in pregnancy are common and can occur as a result of pre-existing hypertension or as new onset hypertension usually in the second half of pregnancy. In either situation there is potential for considerable perinatal and maternal morbidity and mortality. This review article aims to compare therapeutic options outlined in a selection of national guidelines and to look in more detail at the most commonly prescribed drugs - labetalol, methyldopa and nifedipine - with respect to their pharmacology and the evidence for their use in pregnancy. We will also consider the rationale for identifying and treating hypertension in pregnancy and the effect this can have on short- and long-term maternal and neonatal outcomes.