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1.
Curr Rheumatol Rev ; 2024 08 19.
Article de Anglais | MEDLINE | ID: mdl-39162272

RÉSUMÉ

INTRODUCTION: Upadacitinib, a selective JAK1 inhibitor, has demonstrated promising results in the treatment of axial Spondyloarthritis (AxSpA). AxSpA management remains challenging since there is a gap in knowledge regarding the potential effect of upadacitinib in axSpA patients. Exploring novel therapeutic options is crucial. Therefore, we performed this systematic review and meta-analysis to summarize and synthesize results collected from available randomized-- controlled trials (RCTs) about the efficacy and safety of upadacitinib for patients with axSpA. METHODS: A systematic literature search of Medline via PubMed, Web of Science, Scopus, EBSCO, and Cochrane Central was conducted in October 2023. Relevant RCTs were selected, and their data were extracted and analyzed using the RevMan 5.4 software. The main outcomes were assessment in Spondylarthritis International Society (ASAS) 20, ASAS40, SPARCC MRI sacroiliac joint, and Bath Ankylosing Spondylitis disease activity index (BASDAI) 50. RESULTS: Three RCTs with a total of 920 participants were included in this study. Upadacitinib showed significant improvement in the ASAS40 response, ASAS20 response, BASDAI50 response, and SPARCC MRI Sacroiliac Joint change from baseline compared to placebo at 14-week duration (RR 2.19, 95% CI (1.79 to 2.68), P < 0.00001), (RR 1.62, 95% CI [1.42 to 1.84), P < 0.00001), (RR 2.16, 95% CI (1.75 to 2.67), P < 0.00001), and (MD -3.32 points, 95% CI (-3.96 to -2.68), P < 0.00001) respectively. However, this efficacy decreased after the 52-week duration in terms of ASAS40 RR 2.19 vs. 1.02, ASAS20 RR 1.62 vs. 0.98, BASDAI 50 RR 2.16 vs. 1.05, and ASAS Partial Remission RR 3.82 vs. 1.07. CONCLUSION: Upadacitinib 15 mg showed satisfactory and promising efficacy in the treatment of AxSpA, with no difference in safety profile compared to the placebo.

2.
Psychol Res Behav Manag ; 17: 1231-1253, 2024.
Article de Anglais | MEDLINE | ID: mdl-38524287

RÉSUMÉ

Purpose: The purpose of this study is to investigate how smartphone addiction and self-regulation failure influence students' academic life satisfaction considering the impacts of students' mind wandering and cognitive failures. It also sought to look at how students' minds wander, and cognitive failures are affected by smartphone addiction and self-regulation failure among university students. Methods: The WarpPLS-SEM software was used to analyze the research data retrieved from a sample of 950 undergraduate students from universities in Egypt and the Kingdom of Saudi Arabia (KSA). Results: In both countries, the findings revealed that students' smartphone addiction and self-regulation failures negatively affect students' academic life satisfaction and positively affect students' mind wandering and cognitive failures. Additionally, smartphone addiction is positively related to failures of students' self-regulation. Besides the negative influences of students' cognitive failures on their academic life satisfaction, cognitive failures mediated negatively the relationship between mind wandering and students' academic life satisfaction. Finally, students' mind wandering mediated the relationship between smartphone addiction, self-regulation failure, and academic life satisfaction. Discussion: The study introduces fresh insights into the study variables that can be used to expand the literature on academic life satisfaction. The study provides theoretical and practical contributions to students, educators, and policymakers of education.

3.
Fitoterapia ; 172: 105749, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37972716

RÉSUMÉ

Cotton aphids, Aphis gosspyii and cotton jassids, Amrasca biguttula are destructive piercing sucking pests to many strategic crops, especially cotton, not only in Egypt but also all over the world. Using synthetic pesticides to control these pests led to several deleterious impacts. Natural pesticides can be used as a harmless alternative. Nine compounds were isolated from different fractions of Retama raetam using chromatographic techniques and identified by spectroscopic methods as eugenol (1), alpinumisoflavone (2), licoflavone C (3), ephedroidin (4), anagyrine (5), spartiene (6), genistein-8ß-C-glucoside (7), isoprunetin (8) and isoprunetin 7-O-ß-D-glucopyranoside (9). The methanol crude extract and its fractions (hexane, chloroform, ethyl acetate and butanol), as well as the isolated compounds were examined against A. gosspyii and A. biguttula as insecticides. The results showed that chloroform fraction was the most potent fraction against A. gosspyii and A. biguttula, with LC50 values of 65.66 and 64.43 ppm, respectively. As well, compounds 1, 5 and 6 were found to be more active, with LC50 values of 69.84, 25.49 and 27.22 ppm for A. gosspyii and 65.17, 24.07 and 24.78 ppm for A. biguttula, respectively. The most potent compounds (1, 5 and 6) exhibited AChE inhibition toward A. gosspyii compared with the control. So, it can be concluded that the isolated compounds eugenol 1, anagyrine 5 and spartiene 6 are the active principles due to their capability to inhibit AchE activity.


Sujet(s)
Aphides , Insecticides , Animaux , Chloroforme , Eugénol , Structure moléculaire , Extraits de plantes/pharmacologie
4.
Acta Neurochir (Wien) ; 165(11): 3149-3180, 2023 11.
Article de Anglais | MEDLINE | ID: mdl-37695436

RÉSUMÉ

INTRODUCTION: The integration of novel electronic informed consent platforms in healthcare has undergone significant growth over the last decade. Adoption of uniform, accessible, and robust electronic online consenting applications is likely to enhance the informed consent process and improve the patient experience and has the potential to reduce medico-legal ramifications of inadequate consent. A systematic review and meta-analysis was conducted to evaluate the utility of novel electronic means of informed consent in surgical patients and discuss its application to neurosurgical cohorts. METHODS: A review of randomised controlled trials, non-randomised studies of health interventions, and single group pre-post design studies in accordance with the PRISMA statement. Random effects modelling was used to estimate pooled proportions of study outcomes. Patient satisfaction with the informed consent process and patients' gain in knowledge were compared for electronic technologies versus non-electronic instruments. A sub-group analysis was conducted to compare the utility of electronic technologies in neurosurgical cohorts relative to other surgical patients in the context of patient satisfaction and knowledge gain. RESULTS: Of 1042 screened abstracts, 63 studies were included: 44 randomised controlled trials (n = 4985), 4 non-randomised studies of health interventions (n = 387), and 15 single group pre-post design studies (n = 872). Meta-analysis showed that electronic technologies significantly enhanced patient satisfaction with the informed consent process (P < 0.00001) and patients' gain in knowledge (P < 0.00001) compared to standard non-electronic practices. Sub-group analysis demonstrated that neurosurgical patient knowledge was significantly enhanced with electronic technologies when compared to other surgical patients (P = 0.009), but there was no difference in patient satisfaction between neurosurgical cohorts and other surgical patients with respect to electronic technologies (P = 0.78). CONCLUSIONS: Novel electronic technologies can enhance patient satisfaction and increase patients' gain in knowledge of their surgical procedures. Electronic patient education tools can significantly enhance patient knowledge for neurosurgical patients. If used appropriately, these modalities can shorten and/or improve the consent discussion, streamlining the surgical process and improving satisfaction for neurosurgical patients.


Sujet(s)
Neurochirurgie , Humains , Procédures de neurochirurgie , Consentement libre et éclairé , Satisfaction des patients
5.
ACS Omega ; 8(24): 21830-21841, 2023 Jun 20.
Article de Anglais | MEDLINE | ID: mdl-37360433

RÉSUMÉ

Drilling fluids, commonly referred to as drilling mud, are pumped into the wellbore to expedite the drilling process by moving drilling cuttings to the surface, suspending cuttings, controlling pressure, stabilizing exposed rock, and providing buoyancy, cooling, and lubrication. Understanding the settling of drilling cuttings in base fluids is crucial for successfully mixing drilling fluid additives. In this study, the response surface method Box-Benhken design (BBD) is used to analyze the terminal velocity of the drilling cuttings in a polymeric base fluid of carboxymethyl cellulose (CMC). The impact of polymer concentration, fiber concentration, and cutting size on the terminal velocity of the cuttings is investigated. The BBD of the three factors (low, medium, and high) is used for two fiber aspect ratios (3 and 12 mm length). The size of the cuttings varied between 1 and 6 mm, while the concentration of CMC was between 0.49 and 1 wt %. The concentration of the fiber was in the range of 0.02-0.1 wt %. Minitab was utilized to determine the optimum conditions for reducing the terminal velocity of the suspended cuttings and then evaluate the effects and interactions of the components. The results show good agreement between model predictions and the experimental results (R2 = 0.97). According to the sensitivity analysis, cutting size and polymer concentration are the most crucial factors affecting the terminal cutting velocity. Large cutting sizes have the most significant impact on polymer and fiber concentrations. The optimization results revealed that a CMC fluid with a viscosity of 630.4 cP is sufficient to maintain a minimum cutting terminal velocity of 0.234 cm/s with a cutting size of 1 mm and a 0.02 wt % of the 3 mm length fiber.

6.
J Surg Case Rep ; 2023(1): rjad002, 2023 Jan.
Article de Anglais | MEDLINE | ID: mdl-36727122

RÉSUMÉ

Primary meningeal melanocytomas are extremely rare, benign tumours arising from the leptomeninges. While they are considered to be benign lesions, there is potential for their growth and transformation into malignant melanomas. They are commonly found in the cervical spine, with a decreased incidence in the thoracic and lumbar regions. We present a case report of a 56-year-old man who presented to our unit with a 4-month history of lower limb weakness and a sensory level at T6. Magnetic resonance imaging shows an intradural extramedullary tumour. The patient underwent a thoracic debulking of the lesion with neurophysiological monitoring. Histopathology confirmed the diagnosis of melanocytoma of meningeal origin, with a low mitotic count. Our patient recovered well post-operatively with no complications. Surgical resection is an effective method to manage this tumour; however, adjuvant radiotherapy is advised due to the risk of recurrence and malignant transformation.

7.
Br J Neurosurg ; 37(5): 1186-1189, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-32969749

RÉSUMÉ

Anaplastic gangliogliomas of the spinal cord are extremely rare with only four cases reported in the literature. Here we present the case of a 22-year-old female who presented acutely with quadraparesis and urinary retention. Radiographic imaging demonstrated an intramedullary lesion within the cervical spine. She underwent a cervical laminectomy and resection of the lesion under neurophysiological monitoring. Post-operatively, she regained some function, but remained paraparetic. Histopathology demonstrated an anaplastic ganglioglioma (WHO Grade 3). She subsequently underwent radiotherapy. Following surgery, she remained stable and had MRC Grade 3 Power in all four limbs. Herein, we describe a previously undescribed case of cervical anaplastic ganglioglioma and review the existing literature.


Sujet(s)
Tumeurs du cerveau , Tumeurs du système nerveux central , Gangliogliome , Tumeurs de la moelle épinière , Femelle , Humains , Jeune adulte , Adulte , Gangliogliome/imagerie diagnostique , Gangliogliome/chirurgie , Gangliogliome/anatomopathologie , Tumeurs de la moelle épinière/imagerie diagnostique , Tumeurs de la moelle épinière/chirurgie , Tumeurs de la moelle épinière/anatomopathologie , Tumeurs du cerveau/chirurgie , Radiographie , Imagerie par résonance magnétique
8.
Sultan Qaboos Univ Med J ; 23(Spec Iss): 22-30, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-38161766

RÉSUMÉ

Objectives: Post-infarction ventricular septal defect (VSD) is one of the known complications after acute myocardial infarction. This study investigated the clinical results after surgical repair of VSD. Methods: This retrospective study included all patients undergoing surgical repair of VSD from 1996 to 2020 in Oman. Results: Out of a total of 75 patients, 62.5% were men, with a mean age of 59 years. The mean follow-up was 17.2 (7.5) years. Of the 75 patients, 34 (45.3%) patients died within 30 days. Total survival was 41.3% at 5 years, while the 10-year survival rate was 33.3%. Outcomes and predictors for 30 days mortality were the number of concomitant coronary involvement and anastomoses performed, residual postoperative shunt and postoperative dialysis. Conclusion: Even with surgical repair, early mortality of post-infarction septal defect is still considerably high. Early repair and the anatomically posterior rupture are predictors of early mortality. In patients surviving the immediate postoperative period, long-term survival is limited by pre-existing coronary artery disease, postoperative renal failure and the presence of a residual postoperative shunt.


Sujet(s)
Communications interventriculaires , Infarctus du myocarde , Mâle , Humains , Adulte d'âge moyen , Femelle , Études rétrospectives , Résultat thérapeutique , Communications interventriculaires/étiologie , Communications interventriculaires/chirurgie , Infarctus du myocarde/complications , Infarctus du myocarde/chirurgie , Taux de survie
9.
Cureus ; 14(6): e26403, 2022 Jun.
Article de Anglais | MEDLINE | ID: mdl-35915693

RÉSUMÉ

We report a case of a 61-year-old lady presenting with several weeks of progressive left-sided weakness, and found to have a foramen magnum meningioma. She was counselled on surgical resection of the tumour, and a preoperative computed tomography angiogram (CTA) was obtained for operative planning purposes. CTA demonstrated incidental bilateral internal jugular vein (IJV) stenosis, with enlarged extracranial collateral vessels and elongated styloid processes. The main surgical concern was potential injury of the extracranial collateral vessels during operative exposure, which may compromise her intracranial venous outflow in light of the IJV stenosis. A doppler ultrasound scan of the IJVs was performed, which demonstrated that blood flow was still present through both vessels. Through careful soft tissue dissection during surgery, potential complications and injury to the extracranial collaterals were avoided. We performed a literature review of the incidence of IJV stenosis, its associated conditions, and potential surgical implications. Complications from injury to vital collateral extracranial vessels should be considered during preoperative planning in patients with anatomical variants or risk factors for IJV stenosis, as seen in this case.

10.
Br J Neurosurg ; : 1-6, 2022 Apr 18.
Article de Anglais | MEDLINE | ID: mdl-35435093

RÉSUMÉ

OBJECTIVE: Benign spinal intradural tumors are rare entities and there have been relatively few case series describing the epidemiology and characteristics of these tumors. Here, we evaluate the presentation, demographics, pathology and outcomes associated with the surgical management of spinal meningioma in our unit over a 6-year period. RESULTS: A total of 68 cases presented to the operating surgeon during a 6-year period. Of these, over 80% (n = 55) were in females. Seventy-nine percent of the meningiomas were observed in the thoracic region (n = 54). Weakness and gait disturbance were the most common presenting complaints. Surgery significantly improved both motor outcome (p < 0.001) and health related qualities of life (SF36, p < 0.01).Seventeen percent of spinal meningioma cases (n = 12) had a preceding cancer diagnosis. Of these 75% (n = 9/12) were attributable to breast cancer. Overall, breast cancer preceded a diagnosis of a spinal meningioma in 16.4% of female cases (9/55). This is higher than expected number of breast cancer based on UK population and those reported in literature for breast cancer and intracranial meningioma. CONCLUSION: Spinal meningioma is disproportionately over-represented in females. Patients present with neurological deficits and surgery improved both neurology and patient reported quality of life. Relative to the known UK prevalence of breast cancer, there is a significantly higher than expected association between spinal meningioma and a preceding history of breast cancer.

11.
Preprint de Anglais | bioRxiv | ID: ppbiorxiv-478425

RÉSUMÉ

We herein report a study to evaluate the use of computational prediction of SARS-CoV-2 genetic variations in improving the current variants labeling system. First, we reviewed the basis of the system developed by the World Health Organization (WHO) for the labeling of SARS-CoV-2 genetic variants and the adaptations made to it by the United States Center of Diseases Control (CDC). We observed that the labeling system is based upon the virus major attributes. However, we found that the labeling criteria of the SARS-CoV-2 variants derived from these attributes are not accurately defined and are used differently by the two health management agencies. Consequently, discrepancies exist between the labels given by WHO and CDC to same variants. Our observations suggest that giving the VOC label to a new variant is premature and might not be appropriate. Therefore, we carried out a comparative computational study to predict the effects of the mutations on the virus structure and functions of five VOCs. By linking these data to the criteria used by WHO and the CDC for variant labeling, we ascertained that comparative computational predictions of the impact of genetic variations are a better ground for rapid and more accurate labelling of SARS-CoV-2 variants. We propose to label all emergent variants VUM or VBM and to carry out computational predictive studies and thorough variants comparison, upon which more appropriate and informative labels can be attributed. Furthermore, harmonization of the variants labeling system would be globally beneficial to communicate about and fight COVID-19 pandemic.

12.
Int Immunopharmacol ; 99: 107963, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34273638

RÉSUMÉ

Excessive consumption of alcohol may induce severe liver damage, in part via oxidative stress and inflammatory responses, which implicates these processes as potential therapeutic approaches. Prior literature has shown that Telmisartan (TEL) may provide protective effects, presumably mediated by its anti-oxidant and anti-inflammatory activities. The purpose of this study was to determine TEL's hepatoprotective effects and to identify its possible curative mechanisms in alcoholic liver disease. A mouse chronic alcohol plus binge feedings model was used in the current study for induction of alcoholic liver disease (ALD). Our results showed that TEL (10 mg/kg/day) has the ability to reduce serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). TEL also increased the activity of superoxide dismutase (SOD) and glutathione (GSH) with concomitant reduction of nitric oxide (NO) malonaldehyde (MDA) in the liver homogenate. Moreover, TEL downregulated nuclear factor kappa B (NF-κB) expression and decreased liver content of interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α). These anti-inflammatory and anti-oxidant activities were associated with a significant increase in the expression of nuclear factor erythroid 2-related factor 2 (Nrf-2), peroxisome proliferator-activated receptors -γ (PPAR-γ), and heme oxygenase-1 (Hmox-1). In conclusion, TEL's hepatoprotective effects against ALD may be attributable to its anti-inflammatory and anti-oxidant activities which may be in part via the modulation of PPAR-γ/ Nrf-2/ NF-κB crosstalk.


Sujet(s)
Antagonistes du récepteur de type 1 de l'angiotensine-II/usage thérapeutique , Anti-inflammatoires/usage thérapeutique , Hépatite alcoolique/traitement médicamenteux , Facteur-2 apparenté à NF-E2/agonistes , Récepteur PPAR gamma/agonistes , Telmisartan/usage thérapeutique , Alanine transaminase/sang , Alcoolisme/complications , Phosphatase alcaline/sang , Animaux , Antioxydants/pharmacologie , Aspartate aminotransferases/sang , Hyperalcoolisation rapide/complications , Cytokines/métabolisme , Heme oxygenase-1/métabolisme , Mâle , Protéines membranaires/métabolisme , Souris , Souris de lignée BALB C , Agents protecteurs/usage thérapeutique , Interactions entre récepteurs/effets des médicaments et des substances chimiques
13.
World Neurosurg ; 151: e747-e752, 2021 07.
Article de Anglais | MEDLINE | ID: mdl-33957284

RÉSUMÉ

BACKGROUND: Sports-related injuries are the third commonest cause of spine fractures. Spinal fractures incurred as a result of partaking in sport by their nature are different from those associated with frailty and road traffic accidents. The patient demographics and nature of fractures associated with sports activities are not well documented. We aim to describe the management and outcome of patients with a sports-related spine fracture in a single U.K. major trauma center in a 6-year time period. METHODS: Patients with sports-related spinal fractures were identified from the Trauma Audit and Research Network database at a U.K. major trauma center between January 2011 and December 2016. Patient notes were retrospectively reviewed for demographics, injury severity score, treatment, complications, and outcomes. RESULTS: In the study period, 122 patients were admitted with a sports-related spinal fracture, sustaining a total of 230 fractures. Of these, 48 (20.9%) were in the cervical, 79 (34.3%) in the thoracic, and 103 (44.8%) in the lumbar regions. The sports most commonly associated with spinal fractures were horse riding (n = 55), cycling (n = 36), and boating (n = 10). Of the 230 fractures, 32 (13.9%) were associated with neurologic injury. Forty-five of the 230 fractures (19.6%) were managed surgically, and the remainder were managed conservatively. CONCLUSIONS: Within our population, sports most commonly associated with spinal fractures were horse riding, cycling, and boating. The majority of cases were managed nonoperatively. Further research is required to establish evidence-based guidelines on the management of sports-related spinal fractures.


Sujet(s)
Traumatismes sportifs/complications , Traumatismes sportifs/épidémiologie , Fractures du rachis/étiologie , Fractures du rachis/anatomopathologie , Adulte , Sujet âgé , Traumatismes sportifs/thérapie , Femelle , Humains , Mâle , Adulte d'âge moyen , Études rétrospectives , Fractures du rachis/thérapie , Royaume-Uni
14.
Jpn J Radiol ; 39(9): 907-913, 2021 Sep.
Article de Anglais | MEDLINE | ID: mdl-33914254

RÉSUMÉ

PURPOSE: To assess diffusion tensor imaging (DTI) of spleen in prediction and grading of esophageal varices (OV) in cirrhotic children. METHODS: This prospective study was conducted upon 30 children with cirrhotic children with OV and 10 age-gender matched controls that underwent DTI of abdomen. Mean diffusivity (MD) and fractional anisotropy (FA) of spleen were calculated and matched with the grading of OV at endoscopy and laboratory biomarkers of portal hypertension. RESULTS: Mean ADC of spleen in patient was significantly different (p = 0.001) from that of controls by both reviewers respectively. The cutoff ADC measurement of the spleen used for prediction of OV was ≥ 0.75 and ≥ 0.76 × 10-3mm2/s with AUC was 0.993 and 0.997 for both reviewers respectively. The FA of the spleen in patient was different (p = 0.01) from of controls of both reviewers respectively. Cutoff FA of spleen used for prediction of OV was ≤ 0.35 and ≤ 0.36 for both observers respectively. ADC and FA of spleen was correlated with platelets count (r = - 0.713, 0.392; p = 0.001, 0.012) and prothrombin time (r = 0.518, - 0.380; p = 0.001, 0.016). CONCLUSION: DTI metrics of spleen can predict and grade OV and correlated with laboratory biomarkers of portal hypertension.


Sujet(s)
Varices oesophagiennes et gastriques , Hypertension portale , Enfant , Imagerie par tenseur de diffusion , Varices oesophagiennes et gastriques/imagerie diagnostique , Varices oesophagiennes et gastriques/étiologie , Humains , Hypertension portale/complications , Hypertension portale/imagerie diagnostique , Cirrhose du foie/complications , Cirrhose du foie/imagerie diagnostique , Cirrhose du foie/anatomopathologie , Études prospectives , Rate/imagerie diagnostique , Rate/anatomopathologie
15.
Article de Anglais | MEDLINE | ID: mdl-33805375

RÉSUMÉ

BACKGROUND: This literature review investigates the economic costs of childhood disability analysing methodologies used and summarizing the burden worldwide comparing developed and developing countries. METHODS: Four electronic databases were searched. Studies were categorised according to country, perspective, methods of costing, disability category, and time horizon. Annual costs were converted to 2019 current US dollars then compared to the country's per capita current health expenditure (CHE) and gross domestic product (GDP). RESULTS: Of 2468 references identified, 20 were included in the review. Annual burden of childhood disability ranged ≈$450-69,500 worldwide. Childhood disability imposes a heavy economic burden on families, health systems, and societies. The reason for the wide range of costs is the variability in perspective, costs included, methods, and disability type. CONCLUSION: The annual societal costs for one disabled child could be up to the country's GDP per capita. The burden is heavier on households in developing countries as most of the costs are paid out-of-pocket leading to impoverishment of the whole family. Efforts should be directed to avoid preventable childhood disabilities and to support disabled children and their households to make them more independent and increase their productivity. More studies from developing countries are needed.


Sujet(s)
Coûts indirects de la maladie , Dépenses de santé , Enfant , Coûts des soins de santé , Humains
16.
ACS Omega ; 6(4): 2513-2525, 2021 Feb 02.
Article de Anglais | MEDLINE | ID: mdl-33553870

RÉSUMÉ

Fibers are extensively used as a fluid additive in the oil and gas industry to improve hole-cleaning performance, control fluid filtration loss, and enhance hydraulic fracturing effectiveness. Generally, a small amount of fiber is dispersed in the base fluid to achieve the desired results without increasing the viscosity of the base fluid. Nevertheless, sustaining a uniform fiber dispersion can be challenging under wellbore conditions, which is essential for fibers' functionality. Consequently, a better understanding of fiber suspension or stability in base fluids is necessary for their efficient utilization in drilling and completion operations. In this study, response surface methodology (RSM) and box-behnken design (BBD) are used to investigate the stability of fiber in polymeric base suspensions, including carboxy methyl cellulose (CMC), polyacrylamide (PAM), and xanthan gum (XG). The BBD of three factors was selected to observe the influence of polymer concentration, fiber concentration, and temperature on fibrous suspension stability, with three levels of design factors (low, mid, and high) and two fiber aspect ratios (3 and 12 mm fibers). The base fluid polymer concentration ranged from 1 to 8 vol %, fiber concentration ranged from 0.01 to 0.08 wt %, and the temperature was varied from 25 to 80 °C. The stability measurements were analyzed using Minitab, subsequently, evaluating the factors' impact and interactions and determining the optimum conditions for the stability of the fibrous suspensions. The results predicted by the developed model were in good agreement with the experimental results R 2 ≥ 0.91-0.99. The sensitivity analysis showed that base fluid polymer concentration is the most significant factor affecting fibrous suspension stability. At high polymer concentrations, fiber concentration and temperature effects are minimal, while the temperature effect on the stability was observed at low concentrations (e.g., low suspension viscosities). The fiber aspect ratio indirectly affects system stability. Long fibers have a better tendency to entangle and form a structured network, which in turn hinders the buoyancy that induces individual fiber migration. On the contrary, short fibers do not form a network, allowing them to easily migrate to the surface and agglomerate at the top layer (unstable region). Optimization results revealed that suspensions with viscosities above 50 mPa·s are sufficient to maintain the stability of the suspensions at ambient (25 °C) and elevated (80 °C) temperatures.

17.
Global Spine J ; 11(2): 240-248, 2021 Mar.
Article de Anglais | MEDLINE | ID: mdl-32875888

RÉSUMÉ

STUDY DESIGN: Narrative review. OBJECTIVE: The high rate of complications associated with the surgical management of neuromuscular spinal deformities is well documented in the literature. This is attributed to attenuated protective physiological responses in multiple organ systems. METHODS: Review and synthesis of the literature pertaining to optimization of patients with neuromuscular scoliosis undergoing surgery. Our institutional practice in the perioperative assessment and management of neuromuscular scoliosis is also described along with a clinical vignette. RESULTS: Respiratory complications are the most common to occur following surgery for neuromuscular disorders. Other categories include gastrointestinal, cardiac, genitourinary, blood loss, and wound complications. A multidisciplinary approach is required for perioperative optimization of these patients and numerous strategies are described, including respiratory management. CONCLUSION: Perioperative optimization for patients with neuromuscular disorders undergoing corrective surgery for spinal deformity is multifaceted and complex. It requires a multidisciplinary evidence-based approach. Preadmission of patients in advance of surgery for assessment and optimization may be required in certain instances to identify key concerns and formulate a tailored treatment plan.

18.
Br J Neurosurg ; 35(1): 68-72, 2021 Feb.
Article de Anglais | MEDLINE | ID: mdl-32441143

RÉSUMÉ

INTRODUCTION: The acute management of spinal fractures is traditionally split between neurosurgeons and orthopaedic surgeons and the specialities have varying approaches to management. This study investigates differences between neurosurgeons and spinal orthopaedic surgeons in the management of spinal fractures at a single trauma centre in the United Kingdom. METHODS: A retrospective study at a single trauma centre of patients identified using the Trauma Audit and Research Network (TARN). Case notes and radiological investigations were reviewed for demographics, fracture classification, clinical management and outcomes. Polytrauma cases and patients managed by non-neurosurgical/orthopaedic specialties were excluded. RESULTS: A total of 465 patients were included in this study (neurosurgery n = 266, orthopaedics n = 199). There were no significant differences between groups for age, gender, Charlson co-morbidity score or distribution of fractures using the AO spine classification. Patients admitted and managed under the orthopaedic surgeons were more likely to undergo a surgical procedure when compared to those admitted under the neurosurgeons (n = 71; 35.7% vs n = 71; 26.8%, p = 0.042, OR 1.56 95%CI 1.056 to 2.31). The median overall length of stay was 8 days and there was no significant difference between teams; however, the neurosurgical cohort were more likely to be admitted to an intensive care unit (24.3% vs 16.2%, p = 0.04). CONCLUSION: This study is the first in the United Kingdom to compare neurosurgical and orthopaedic teams in their management of spinal fractures. It demonstrates that differences may exist both in operating rates and outcomes.


Sujet(s)
Neurochirurgie , Orthopédie , Fractures du rachis , Humains , Études rétrospectives , Fractures du rachis/imagerie diagnostique , Fractures du rachis/chirurgie , Royaume-Uni/épidémiologie
19.
World Neurosurg ; 145: e274-e277, 2021 01.
Article de Anglais | MEDLINE | ID: mdl-33065345

RÉSUMÉ

OBJECTIVE: Although chronic subdural hematomas (cSDH) are often treated surgically it remains plausible that invasive treatment in elderly patients may have a negative effect on survival. The aim of this study was to characterize survival following neurosurgical intervention for cSDH in a selected cohort aged >90 years and to identify prognostic factors that may inform clinical decision-making. METHODS: In total, we identified a cohort of 548 consecutive patients who had undergone burr hole drainage for cSDH in a 5-year period between 2009-2013. Of these patients, 41 were aged >90 years. For each patient, information was gathered from local hospital records, general practice records, and the patients directly. Long-term survival was compared with actuarial data obtained from the National Life Tables. RESULTS: Overall mortality at the time of discharge was 2%. Mortality was 26.8% at 6 months, 36.8% at 1 year, and 47.9% at 2 years. Interestingly, there was no significant difference between the actuarial curve and the survival curve following surgery (hazard ratio, 1.17; confidence interval, 0.67-2.05; P = 0.57). Despite initially departing from the actuarial curve, the survival curve becomes parallel at approximately 1 year. Multivariate analysis showed that preadmission residence and the number of comorbid conditions were significant predictors of survival. CONCLUSIONS: We advocate that neurosurgical intervention for cSDH in selected nonagenarians can be a safe and beneficial procedure. Patients living independently at home and with a limited past medical history were most likely to benefit from the surgery.


Sujet(s)
Hématome subdural chronique/mortalité , Hématome subdural chronique/chirurgie , Trépanation/mortalité , Trépanation/méthodes , Sujet âgé de 80 ans ou plus , Femelle , Humains , Mâle
20.
Braz. dent. sci ; 24(3): 1-10, 2021. tab, ilus, graf
Article de Anglais | BBO - Ondontologie , LILACS | ID: biblio-1282057

RÉSUMÉ

Objective: The aim of this study was to analyze mechanical and thermal stresses of hybrid ceramic and lithium disilicate based ceramic of CAD/CAM inlays using 3D Finite element analysis. Material and Methods:A three dimensions finite element model of permanent maxillary premolar designed according to standard anatomy with class II cavity preparation for inlay restored with two different ceramic materials: 1- Hybrid ceramic (Vita Enamic), 2- Lithium disilicate based ceramic (IPS e.max CAD). Totally six runs were performed on the model as: One loading case for each restorative material was tested in stress analysis; seven points of loading with 140N vertically applied at palatal cusp tip and cusp slop, marginal ridges and central fossa while the models base was fixed as a boundary condition in the two cases. Two thermal analysis cases were performed for each restoration material by applying 5ºC and 55ºC on the crown surface including the restoration surface. Results:The results of all structures were separated from the rest of the model to analyze the magnitude of stress in each component. For each group, maximum stresses on restorative materials, cement, enamel, and dentin were evaluated separately. Both ceramic materials generated similar stress distribution patterns for all groups when a total occlusal load of 140 N was applied. Conclusion: Thermal fluctuations of temperature have a great influence on the stresses induced on both restoration and tooth structure. IPS e.max CAD produced more favorable stresses on the tooth structure than Vita Enamic. (AU)


Objetivo: O objetivo deste estudo foi analisar o estresse mecânico e térmico de inlays de cerâmica hibrida e a base de dissilicato de lítio através da análise em 3D de elementos finitos. Material e Métodos: Foi realizado o design de um modelo de três dimensões em elementos finitos de um pré-molar superior de acordo com os padrões anatômicos de um preparo de cavidade classe II para restauração de inlay em dois tipos de cerâmicas diferentes: 1 Cerâmica hibrida (Vita Enamic), 2 ­ Cerâmica a base de dissilicato de lítio (IPS e.max CAD). No total, seis execuções foram realizadas no modelo como: Uma carga para cada material restaurador foi testado para análise de tensão; sete pontos de carga com 140N foi aplicado verticalmente na ponta da cúspide palatina, saliência da cúspide, cristas marginais e fossa central enquanto a base do modelo foi fixada como uma condição de limite nos dois casos. Duas análises térmicas foram realizadas para cada material de restauração, aplicando 5ºC e 55ºC na superfície da coroa, incluindo a superfície da restauração. Resultados: Os resultados de todas as estruturas foram separados do resto do modelo para analisar a magnitude do estresse de cada componente. Para cada grupo, o máximo de estresse nos materiais restauradores, cemento, esmalte e dentina foram avaliados separadamente. Padrões similares de distribuição de estresse foram gerados em todos os grupos para ambos os materiais cerâmicos, quando a carga oclusal de 140 N foi aplicada. Conclusão: As variações térmicas de temperatura têm uma grande influência nas tensões induzidas na restauração e na estrutura dentária. IPS e.max CAD produziu tensões mais favoráveis na estrutura dentária do que o Vita Enamic (AU)


Sujet(s)
Prémolaire , Analyse des éléments finis , Préparation de cavité dentaire , Cément dentaire , Émail dentaire , Dentine
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