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1.
Soft Matter ; 20(10): 2258-2271, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38353299

RESUMO

We conduct a systematic exploration of the energy landscape of vesicle morphologies within the framework of the Helfrich model. Vesicle shapes are determined by minimizing the elastic energy subject to constraints of constant area and volume. The results show that pressurized vesicles can adopt higher-energy spindle-like configurations that require the action of point forces at the poles. If the internal pressure is lower than the external one, multilobed shapes are predicted. We utilize our results to rationalize experimentally observed spindle shapes of giant vesicles in a uniform AC electric field.

2.
Proc Natl Acad Sci U S A ; 118(24)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34117125

RESUMO

Short liquid bridges are stable under the action of surface tension. In applications like electronic packaging, food engineering, and additive manufacturing, this poses challenges to the clean and fast dispensing of viscoelastic fluids. Here, we investigate how viscoelastic liquid bridges can be destabilized by torsion. By combining high-speed imaging and numerical simulation, we show that concave surfaces of liquid bridges can localize shear, in turn localizing normal stresses and making the surface more concave. Such positive feedback creates an indent, which propagates toward the center and leads to breakup of the liquid bridge. The indent formation mechanism closely resembles edge fracture, an often undesired viscoelastic flow instability characterized by the sudden indentation of the fluid's free surface when the fluid is subjected to shear. By applying torsion, even short, capillary stable liquid bridges can be broken in the order of 1 s. This may lead to the development of dispensing protocols that reduce substrate contamination by the satellite droplets and long capillary tails formed by capillary retraction, which is the current mainstream industrial method for destabilizing viscoelastic liquid bridges.

3.
Afr J Reprod Health ; 28(3): 99-113, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38583073

RESUMO

Menopause represents the physiological transition when a woman's reproductive period ends associated with a variety of symptoms, including vasomotor symptoms, such as night sweats and hot flashes. This systematic review and meta-analysis aimed to assess the effectiveness and safety of oral Fezolinetant for treating vasomotor symptoms associated with menopause. Five electronic databases were searched from their inception until May 2023. Via the Cochrane risk of bias tool, two reviewers assessed the studies' quality. The primary outcomes were a decrease in VMSs frequency and severity and safety outcomes at 4 and 12 weeks. Data were extracted and then analyzed using RevMan software. This meta-analysis included six trials with a total of 3291 women that compared Fezolinetant to a placebo in the treatment of menopausal VMSs. After 4 and 12 weeks of therapy, fezolinetant at 30 mg QD or 45 mg QD substantially decreased the frequency and severity of VMSs per 24 hours compared to placebo. Fezolinetant at 90 mg BID, 30 mg QD, or 45 mg QD did not show a significant difference in the rate of treatment-emergent adverse events (TEAEs), headache, and TEAEs leading to permanent discontinuation compared to placebo. Fezolinetant proves to be a successful and well-tolerated remedy for menopausal women suffering from VMSs. Notably, the 45 mg daily dosage over 12 weeks exhibited significant efficacy. Nonetheless, extensive future trials are necessary to ascertain its long-term safety, effectiveness, and relative potency compared to alternative VMS treatments like hormone therapy.


La ménopause représente la transition physiologique lorsque la période de reproduction d'une femme se termine, associée à divers symptômes, notamment des symptômes vasomoteurs, tels que des sueurs nocturnes et des bouffées de chaleur. Cette revue systématique et méta-analyse visaient à évaluer l'efficacité et l'innocuité du Fezolinetant oral pour traiter les symptômes vasomoteurs associés à la ménopause. Cinq bases de données électroniques ont été consultées depuis leur création jusqu'en mai 2023. Via l'outil Cochrane sur le risque de biais, deux examinateurs ont évalué la qualité des études. Les principaux critères de jugement étaient une diminution de la fréquence et de la gravité des SVM ainsi que des critères de sécurité à 4 et 12 semaines. Les données ont été extraites puis analysées à l'aide du logiciel RevMan. Cette méta-analyse comprenait six essais portant sur un total de 3 291 femmes comparant Fezolinetant à un placebo dans le traitement des SVM ménopausiques. Après 4 et 12 semaines de traitement, le fézolinetant à la dose de 30 mg une fois par jour ou de 45 mg une fois par jour a considérablement réduit la fréquence et la gravité des SMV toutes les 24 heures par rapport au placebo. Le fézolinetant à la dose de 90 mg deux fois par jour, de 30 mg une fois par jour ou de 45 mg une fois par jour n'a pas montré de différence significative dans le taux d'événements indésirables survenus pendant le traitement (TEAE), de maux de tête et de TEAE conduisant à un arrêt définitif par rapport au placebo. Le fézolinetant s'avère être un remède efficace et bien toléré pour les femmes ménopausées souffrant de VMS. Notamment, la dose quotidienne de 45 mg sur 12 semaines a montré une efficacité significative. Néanmoins, de futurs essais approfondis sont nécessaires pour vérifier son innocuité, son efficacité et sa puissance relative à long terme par rapport aux traitements alternatifs du VMS comme l'hormonothérapie.


Assuntos
Compostos Heterocíclicos com 2 Anéis , Tiadiazóis , Humanos , Feminino , Menopausa , Fogachos/tratamento farmacológico , Compostos Heterocíclicos com 2 Anéis/uso terapêutico , Tiadiazóis/uso terapêutico
4.
Neurosurg Focus ; 55(6): E4, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38039535

RESUMO

OBJECTIVE: Controlling length of stay (LOS) reduces rates of nosocomial infections and falls, facilitates earlier return to daily activities, and decreases strain on the healthcare system. Complications following supratentorial tumor resection present early in the postoperative period, thereby enhancing the prospect of safe, early discharge. Here, the authors describe their initial experience with the development and implementation of an Enhanced Recovery After Cranial Surgery (ERACS) pathway following resection of supratentorial tumors in select patients. METHODS: This was a nonrandomized, ambispective quality improvement study of patients undergoing elective craniotomy for supratentorial tumor resection at New York University Langone Health between November 17, 2020, and May 19, 2022. Eligible patients were prospectively enrolled in either the ERACS pathway or the standard pathway. These prospective cohorts were compared to a retrospective cohort of patients who met eligibility criteria for the pathway. Patients in the ERACS pathway cohort were targeted for discharge on postoperative day 2. The primary outcome metric was hospital LOS. Secondary outcome metrics included duration of intensive care unit (ICU) care and rates of 30-day emergency department visits, readmissions, and complications. RESULTS: Over the study period, 188 of 317 patients (59.3%) who underwent supratentorial tumor resection met inclusion criteria for ERACS pathway enrollment. Sixty-three patients were enrolled in the ERACS pathway, and 125 patients completed the standard pathway. The historical cohort consisted of 332 patients who would have been eligible for ERACS enrollment. Patients in the ERACS pathway cohort had a median LOS of 1.93 days compared with 2.92 and 2.88 days for patients in the standard pathway and historical cohort, respectively (p < 0.001). There was a significant reduction in ICU utilization in ERACS pathway patients (16.0 ± 6.53 vs 29.5 ± 53.0 vs 21.8 ± 18.2 hours, p = 0.005). There were no differences in the rates of 30-day emergency department visits (12.7% vs 9.6% vs 10.9%, p = 0.809) and readmissions (4.8% vs 4.0% vs 7.8%, p = 0.279) between groups. CONCLUSIONS: Patients in the ERACS pathway cohort experienced reduced LOS and ICU utilization, with similar rates of adverse outcomes compared to standard pathway patients. The authors' initial experience suggests that an accelerated recovery pathway can be safely implemented following supratentorial tumor resection in select patients.


Assuntos
Recuperação Pós-Cirúrgica Melhorada , Neoplasias Supratentoriais , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Centros de Atenção Terciária , Tempo de Internação , Neoplasias Supratentoriais/cirurgia , Complicações Pós-Operatórias
5.
Neurocrit Care ; 38(1): 85-95, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36114314

RESUMO

BACKGROUND: Factors associated with discharge disposition and mortality following aneurysmal subarachnoid hemorrhage (aSAH) are not well-characterized. We used a national all-payer database to identify factors associated with home discharge and in-hospital mortality. METHODS: The National Inpatient Sample was queried for patients with aSAH within a 4-year range. Weighted multivariable logistic regression models were constructed and adjusted for age, sex, race, household income, insurance status, comorbidity burden, National Inpatient Sample SAH Severity Score, disease severity, treatment modality, in-hospital complications, and hospital characteristics (size, teaching status, and region). RESULTS: Our sample included 37,965 patients: 33,605 were discharged alive and 14,350 were discharged home. Black patients had lower odds of in-hospital mortality compared with White patients (adjusted odds ratio [aOR] = 0.67, 95% confidence interval [CI] 0.52-0.86, p = 0.002). Compared with patients with private insurance, those with Medicare were less likely to have a home discharge (aOR = 0.58, 95% CI 0.46-0.74, p < 0.001), whereas those with self-pay (aOR = 2.97, 95% CI 2.29-3.86, p < 0.001) and no charge (aOR = 3.21, 95% CI 1.57-6.55, p = 0.001) were more likely to have a home discharge. Household income percentile was not associated with discharge disposition or in-hospital mortality. Paradoxically, increased number of Elixhauser comorbidities was associated with significantly lower odds of in-hospital mortality. CONCLUSIONS: We demonstrate independent associations with hospital characteristics, patient characteristics, and treatment characteristics as related to discharge disposition and in-hospital mortality following aSAH, adjusted for disease severity.


Assuntos
Hemorragia Subaracnóidea , Humanos , Idoso , Estados Unidos/epidemiologia , Hemorragia Subaracnóidea/complicações , Alta do Paciente , Mortalidade Hospitalar , Estudos Retrospectivos , Medicare
6.
Afr J Reprod Health ; 27(1): 95-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37584961

RESUMO

Cesarean sections are the most common operations in the United States and one of the most common worldwide. Using the lowest possible dose of anesthetic that provides painless delivery with the lowest adverse events is a major concern. We investigated the efficacy and safety of combined ropivacaine and sufentanil by pooling data from relevant studies. We searched PubMed, Web of sciences, Scopus, and Cochrane Library until the end of December 2021 and included all records with data about combined ropivacaine and sufentanil. We used Review Manager to pool data as a mean difference for continuous outcomes or risk ratio for dichotomous outcomes with a 95% confidence interval. Methodological quality was appraised using version one of the Cochrane risks of bias tool. Seven Randomized clinical trials with a total sample size of 730 women were included; the mean age of enrolled parturients ranged from 28 to 35 years. We found that combined sufentanil and ropivacaine were significantly associated with decreased risk of being aware and nervous during CS (presented by Sedation level 1) (RR: 0.05, 95%CI [0.01,0.33], P=0.002), decreased risk of shivering (RR=0.29, 95%CI [0.19,0.44], P<0.00001), nausea (RR=0.62, 95%CI [0.41, 0.92], P=0.02), and vomiting (RR=0.27, 95% CI [0.12, 0.61], P=0.002). However, combined sufentanil and ropivacaine slightly were associated with late-onset of sensory blockade (MD=0.41, 95%CI [0.13, 0.68], P=0.004) and less motor blockade of leg flexion at hip joint presented by Bromage Scale 0 (RR=7.15 95%CI [2.71, 18.86], P<0.0001). Combined ropivacaine and sufentanil were associated with a reduction in visceral pain and lower risks of hypotension, shivering, nausea, and vomiting, compared to isolated ropivacaine, with no difference regarding the incidence of bradycardia. Although Combined ropivacaine and sufentanil were associated with a higher risk of pruritus, the incidence of pruritus was reportedly proportionate with the used dose of sufentanil. However, combined ropivacaine and sufentanil may slightly delay the onset of the sensory blockade to pinprick at T10 with less motor blockade but with a smaller probability for women to be aware and nervous during CS.


Assuntos
Anestésicos Locais , Sufentanil , Feminino , Gravidez , Humanos , Adulto , Ropivacaina/efeitos adversos , Sufentanil/efeitos adversos , Anestésicos Locais/efeitos adversos , Cesárea , Amidas/efeitos adversos , Vômito/induzido quimicamente , Vômito/complicações , Náusea/induzido quimicamente , Náusea/complicações , Prurido/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Afr J Reprod Health ; 27(4): 84-95, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37584912

RESUMO

Induction of labor (IOL) is the stimulation of the uterus during pregnancy to begin the onset of labour. Nearly two of five pregnancies require IOL. We compared the effectiveness of double-balloon catheter (DBC) with dinoprostone (PGE-2) insert for labour induction from previous studies. We included randomized controlled trials (RCTs) that compared the safety and efficacy of DBC to PGE-2. To evaluate the studies, we utilized the Cochrane tool for risk of bias assessment. The rates of vaginal birth and cesarean section were the primary outcomes. We included ten RCTs in this meta-analysis with a total sample of 2493 singleton pregnancies. After 24 hours, there was no significant difference in the delivery rates between DBC and PGE-2 s [R.R=1.08, 95% CI, (0.77, 1.52), P.value=0.65], and the rate of cesarean delivery [R.R=1.03, 95% CI, (0.90; 1.18), P.value=0.65]. The DBC showed a significantly higher oxytocin use rate compared to the PGE-2 group [R.R=1.77, 95% CI, (1.41; 2.32), P.value<0.0001]. In the PGE-2 group, there was a significantly higher risk of uterine hyperstimulation, tachysystole, and umbilical artery PH levels below 7. There was no significant difference in the efficacy between the PGE-2 and DBC in terms of delivery rate in 24 hours and the rate of cesarean delivery except for a slight BISHOP score improvement with DBC. However, DBC showed a higher rate of oxytocin use compared to the PGE-2, the DBC seems to be safer with a lower risk of umbilical artery PH < 7, uterine hyperstimulation, and tachysystole incidence than PGE-2.


Assuntos
Dinoprostona , Ocitócicos , Gravidez , Feminino , Humanos , Dinoprostona/uso terapêutico , Dinoprostona/farmacologia , Ocitócicos/efeitos adversos , Ocitocina/uso terapêutico , Trabalho de Parto Induzido , Catéteres
8.
Afr J Reprod Health ; 27(11): 99-125, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38053339

RESUMO

We compare the hematocrit, hemoglobin, need for transfusion, recurrent phototherapy, serum bilirubin level, and serum ferritin at different time frames for the umbilical cord milking (UCM) and delayed cord clamping (DCC) in both full-term and preterm infants. A comprehensive search through various databases aimed to compare UCM and DCC studies until May 2nd, 2023. Cochrane and NIH tools assessed RCTs and cohorts, respectively. Meta-analysis employed Review Manager 5.4 software, calculating MD and RR with 95% CIs for continuous and dichotomous data. We included 20 studies with a total of 5189 infants. Regarding preterm infants, hematocrit level showed no significant difference between intact Umbilical Cord Milking (iUCM) compared to DCC (MD = -0.24, 95% CI [-1.11, 0.64]). Moreover, Neonatal death incidence was significantly higher with the UCM technique in comparison to DCC (RR = 1.28, 95% CI [1.01 to 1.62]). Regarding term and late preterm infants, Hematocrit level showed no significant difference between the iUCM or cUCM techniques compared to DCC (MD = 0.21, 95% CI [-1.28 to 1.69]), (MD = 0.96, 95% CI [-1.02 to 2.95]), respectively. UCM led to a higher risk of neonatal death in preterm infants compared to DCC. However, the incidence of polycythemia was lower in the UCM group. Additionally, UCM was associated with higher rates of severe IVH events. Based on these findings, DCC may be preferred due to its lower incidence of severe IVH and neonatal death.


Nous comparons l'hématocrite, l'hémoglobine, le besoin de transfusion, la photothérapie récurrente, le taux de bilirubine sérique et la ferritine sérique à différentes périodes pour la traite du cordon ombilical (UCM) et le clampage retardé du cordon (DCC) chez les nourrissons nés à terme et prématurés. Une recherche complète dans diverses bases de données visait à comparer les études UCM et DCC jusqu'au 2 mai 2023. Les outils Cochrane et NIH ont évalué les ECR et les cohortes, respectivement. La méta-analyse a utilisé le logiciel Review Manager 5.4, calculant le MD et le RR avec des IC à 95 % pour les données continues et dichotomiques. Nous avons inclus 20 études portant sur un total de 5 189 nourrissons. Concernant les nourrissons prématurés, le niveau d'hématocrite n'a montré aucune différence significative entre la traite du cordon ombilical intact (iUCM) et la DCC (DM = -0,24, IC à 95 % [-1,11, 0,64]). De plus, l'incidence des décès néonatals était significativement plus élevée avec la technique UCM qu'avec la technique DCC (RR = 1,28, IC à 95 % [1,01 à 1,62]). Concernant les nourrissons à terme et peu prématurés, le niveau = 0,21, IC à 95 % [-1,28 à 1,69]), (DM = 0,96, IC à 95 % [-1,02 à 2,95]), respectivement. L'UCM a entraîné un risque plus élevé de décès néonatal chez les nourrissons prématurés par rapport au DCC. Cependant, l'incidence de la polyglobulie était plus faible dans le groupe UCM. De plus, l'UCM était associée à des taux plus élevés d'événements IVH graves. Sur la base de ces résultats, le DCC peut être préféré en raison de sa plus faible incidence d'IVH grave et de décès néonatals. d'hématocrite n'a montré aucune différence significative entre les techniques iUCM ou cUCM par rapport à la technique DCC (DM.


Assuntos
Recém-Nascido Prematuro , Morte Perinatal , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Clampeamento do Cordão Umbilical , Cordão Umbilical , Hematócrito
9.
Afr J Reprod Health ; 27(7): 99-108, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37742338

RESUMO

We aim to collect the evidence of efficacy of Gentle Guman Touch (GHT) and Yakson Touch in preterm neonates as pain relief, heart rate, oxygen saturation, and urine cortisol level. We made our search through PubMed, Web of Science, Scopus, and Cochrane by the mid of March 2023. Randomized control trials (RCTs) were included, and the Cochrane risk of bias tool was utilized to assess their quality. Using Review Manager software, a meta-analysis was conducted. We computed the mean difference (MD) with a 95% confidence interval (CI) for the continuous data. During the examination, the Neonatal Infant Pain Scale (NIPS) was significantly reduced in the touch group compared to the control group (MD = -3.40, 95% CI [-4.15 to -2.64], P-value= 0.00001). After the examination, the NIPS score was also reduced by both Yakson touch and GHT compared to the control (MD = -2.14, 95% CI [-3.42 to -0.85], P-value <0.00001). Yakson touch and GHT are non-pharmacological, easy, and safe methods that can be used for painful interventions to reduce the pain experience of preterm infants from variable interventions. Both methods improved infant sleep and behavior. Preterm infants' heart rates and oxygen saturation were unaffected by Yakson touch or GHT.


Assuntos
Recém-Nascido Prematuro , Tato , Humanos , Lactente , Recém-Nascido , Dor/prevenção & controle
10.
Biophys J ; 121(6): 910-918, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35176271

RESUMO

Viscosity is a key property of cell membranes that controls mobility of embedded proteins and membrane remodeling. Measuring it is challenging because existing approaches involve complex experimental designs and/or models, and the applicability of some methods is limited to specific systems and membrane compositions. As a result there is scarcity of systematic data, and the reported values for membrane viscosity vary by orders of magnitude for the same system. Here, we show how viscosity of membranes can be easily obtained from the transient deformation of giant unilamellar vesicles. The approach enables a noninvasive, probe-independent, and high-throughput measurement of the viscosity of membranes made of lipids or polymers with a wide range of compositions and phase state. Using this novel method, we have collected a significant amount of data that provides insights into the relation between membrane viscosity, composition, and structure.


Assuntos
Polímeros , Lipossomas Unilamelares , Lipídeos/química , Membranas , Lipossomas Unilamelares/química , Viscosidade
11.
Langmuir ; 38(34): 10548-10557, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35993569

RESUMO

Closed lipid bilayers in the form of giant unilamellar vesicles (GUVs) are commonly used membrane models. Various methods have been developed to prepare GUVs, however it is unknown if all approaches yield membranes with the same elastic, electric, and rheological properties. Here, we combine flickering spectroscopy and electrodefomation of GUVs to measure, at identical conditions, membrane capacitance, bending rigidity and shear surface viscosity of palmitoyloleoylphosphatidylcholine (POPC) membranes formed by several commonly used preparation methods: thin film hydration (spontaneous swelling), electroformation, gel-assisted swelling using poly(vinyl alcohol) (PVA) or agarose, and phase-transfer. We find relatively similar bending rigidity value across all the methods except for the agarose hydration method. In addition, the capacitance values are similar except for vesicles prepared via PVA gel hydration. Intriguingly, membranes prepared by the gel-assisted and phase-transfer methods exhibit much higher shear viscosity compared to electroformation and spontaneous swelling, likely due to remnants of polymers (PVA and agarose) and oils (hexadecane and mineral) in the lipid bilayer structure.


Assuntos
Bicamadas Lipídicas , Lipossomas Unilamelares , Bicamadas Lipídicas/química , Óleos , Sefarose , Lipossomas Unilamelares/química , Viscosidade
12.
Proc Natl Acad Sci U S A ; 116(33): 16529-16534, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31358625

RESUMO

Treatment of Staphylococcus aureus infections is complicated by the development of antibiotic tolerance, a consequence of the ability of S. aureus to enter into a nongrowing, dormant state in which the organisms are referred to as persisters. We report that the clinically approved anthelmintic agent bithionol kills methicillin-resistant S. aureus (MRSA) persister cells, which correlates with its ability to disrupt the integrity of Gram-positive bacterial membranes. Critically, bithionol exhibits significant selectivity for bacterial compared with mammalian cell membranes. All-atom molecular dynamics (MD) simulations demonstrate that the selectivity of bithionol for bacterial membranes correlates with its ability to penetrate and embed in bacterial-mimic lipid bilayers, but not in cholesterol-rich mammalian-mimic lipid bilayers. In addition to causing rapid membrane permeabilization, the insertion of bithionol increases membrane fluidity. By using bithionol and nTZDpa (another membrane-active antimicrobial agent), as well as analogs of these compounds, we show that the activity of membrane-active compounds against MRSA persisters positively correlates with their ability to increase membrane fluidity, thereby establishing an accurate biophysical indicator for estimating antipersister potency. Finally, we demonstrate that, in combination with gentamicin, bithionol effectively reduces bacterial burdens in a mouse model of chronic deep-seated MRSA infection. This work highlights the potential repurposing of bithionol as an antipersister therapeutic agent.


Assuntos
Antibacterianos/farmacologia , Membrana Celular/efeitos dos fármacos , Reposicionamento de Medicamentos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Animais , Bitionol/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Colesterol/química , Modelos Animais de Doenças , Sinergismo Farmacológico , Gentamicinas/farmacologia , Bicamadas Lipídicas/química , Fluidez de Membrana/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Simulação de Dinâmica Molecular , Fosfatidilcolinas/química , Relação Estrutura-Atividade , Lipossomas Unilamelares
13.
Neurosurg Focus ; 52(5): E7, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35535821

RESUMO

OBJECTIVE: Neurofibromatosis type 1 (NF1) dystrophic scoliosis is an early-onset, rapidly progressive multiplanar deformity. There are few studies on the surgical management of this patient population. Specifically, perioperative morbidity, instrument-related complications, and quality-of-life outcomes associated with surgical management have not been systematically evaluated. In this study, the authors aimed to perform a systematic review on the natural history, management options, and surgical outcomes in patients who underwent NF1 dystrophic scoliosis surgery. METHODS: A PubMed search for articles with "neurofibromatosis" and either "dystrophic" or "scoliosis" in the title or abstract was performed. Articles with 10 or more patients undergoing surgery for NF1 dystrophic scoliosis were included. Data regarding indications, treatment details, morbidity, and outcomes were summarized and analyzed with descriptive statistics. RESULTS: A total of 310 articles were identified, 48 of which were selected for full-text review; 30 studies describing 761 patients met the inclusion criteria. The mean age ranged from 7 to 22 years, and 99.7% of patients were younger than 18 years. The mean preoperative coronal Cobb angle was 75.2°, and the average correction achieved was 40.3°. The mean clinical follow-up in each study was at least 2 years (range 2.2-19 years). All patients underwent surgery with the intent of deformity correction. The scoliosis regions addressed were thoracic curves (69.6%) and thoracolumbar (11.1%) and lumbar (14.3%) regions. The authors reported on a variety of approaches: posterior-only, combined anterior-posterior, and growth-friendly surgery. For fixation techniques, 42.5% of patients were treated with hybrid constructs, 51.5% with pedicle screw-only constructs, and 6.0% with hook-based constructs. Only 0.9% of patients underwent a vertebral column resection. The nonneurological complication rate was 14.0%, primarily dural tears and wound infections. The immediate postoperative neurological deficit rate was 2.1%, and the permanent neurological deficit rate was 1.2%. Ultimately, 21.5% required revision surgery, most commonly for implant-related complications. Loss of correction in both the sagittal and coronal planes commonly occurred at follow-up. Five papers supplied validated patient-reported outcome measures, showing improvement in the mental health, self-image, and activity domains. CONCLUSIONS: Data on the surgical outcomes of dystrophic scoliosis correction are heterogeneous and sparse. The perioperative complication rate appears to be high, although reported rates of neurological deficits appear to be lower than clinically observed and may be underreported. The incidence of implant-related failures requiring revision surgery is high. There is a great need for multicenter prospective studies of this complex type of deformity.


Assuntos
Neurofibromatose 1 , Escoliose , Fusão Vertebral , Adolescente , Adulto , Criança , Humanos , Estudos Multicêntricos como Assunto , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico por imagem , Neurofibromatose 1/cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos , Estudos Retrospectivos , Escoliose/complicações , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Resultado do Tratamento , Adulto Jovem
14.
Biophys J ; 120(11): 2317-2329, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33887229

RESUMO

Polyunsaturated fatty acids (PUFAs) modify the activity of a wide range of membrane proteins and are increasingly hypothesized to modulate protein activity by indirectly altering membrane physical properties. Among the various physical properties affected by PUFAs, the membrane area expansion modulus (Ka), which measures membrane strain in response to applied force, is expected to be a significant controller of channel activity. Yet, the impact of PUFAs on membrane Ka has not been measured previously. Through a series of micropipette aspiration studies, we measured the apparent Ka (Kapp) of phospholipid model membranes containing nonesterified fatty acids. First, we measured membrane Kapp as a function of the location of the unsaturated bonds and degree of unsaturation in the incorporated fatty acids and found that Kapp generally decreases in the presence of fatty acids with three or more unsaturated bonds. Next, we assessed how select ω-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), affect the Kapp of membranes containing cholesterol. In vesicles prepared with high amounts of cholesterol, which should increase the propensity of the membrane to phase segregate, we found that inclusion of DHA decreases the Kapp in comparison to EPA. We also measured how these ω-3 PUFAs affect membrane fluidity and bending rigidity to determine how membrane Kapp changes in relation to these other physical properties. Our study shows that PUFAs generally decrease the Kapp of membranes and that EPA and DHA have differential effects on Kapp when membranes contain higher levels of cholesterol. Our results suggest membrane phase behavior and the distribution of membrane-elasticizing amphiphiles impact the ability of a membrane to stretch.


Assuntos
Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Colesterol , Elasticidade , Ácidos Graxos Insaturados
15.
Electrophoresis ; 42(20): 2027-2032, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34297846

RESUMO

We describe a facile method to simultaneously measure the bending rigidity and capacitance of biomimetic lipid bilayers. Our approach utilizes the ellipsoidal deformation of quasi-spherical giant unilamellar vesicles induced by a uniform AC electric field. Vesicle shape depends on the electric field frequency and amplitude. Membrane bending rigidity can be obtained from the variation of the vesicle elongation on either field amplitude at fixed frequency or frequency at fixed field amplitude. Membrane capacitance is determined from the frequency at which the vesicle shape changes from prolate to oblate ellipsoid as the frequency is increased at a given field amplitude.


Assuntos
Materiais Biomiméticos , Biomimética , Eletricidade , Lipossomas Unilamelares , Fenômenos Biomecânicos , Bicamadas Lipídicas
16.
J Exp Bot ; 72(4): 1271-1281, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33252664

RESUMO

A growing number of leaf traits can be estimated from hyperspectral reflectance data. These include structural and compositional traits, such as leaf mass per area (LMA) and nitrogen and chlorophyll content, but also physiological traits such a Rubisco carboxylation activity, electron transport rate, and respiration rate. Since physiological traits vary with leaf temperature, how does this impact on predictions made from reflectance measurements? We investigated this with two wheat varieties, by repeatedly measuring each leaf through a sequence of temperatures imposed by varying the air temperature in a growth room. Leaf temperatures ranging from 20 °C to 35 °C did not alter the estimated Rubisco capacity normalized to 25 °C (Vcmax25), or chlorophyll or nitrogen contents per unit leaf area. Models estimating LMA and Vcmax25/N were both slightly influenced by leaf temperature: estimated LMA increased by 0.27% °C-1 and Vcmax25/N increased by 0.46% °C-1. A model estimating Rubisco activity closely followed variation associated with leaf temperature. Reflectance spectra change with leaf temperature and therefore contain a temperature signal.


Assuntos
Fotossíntese , Triticum , Dióxido de Carbono , Clorofila , Nitrogênio , Folhas de Planta , Temperatura
17.
Neurosurg Focus ; 50(5): E15, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33932922

RESUMO

OBJECTIVE: Separation surgery followed by spine stereotactic radiosurgery (SSRS) has been shown to achieve favorable rates of local tumor control and patient-reported outcomes in patients with metastatic epidural spinal cord compression (MESCC). However, rates and factors associated with adjacent-level tumor progression (ALTP) in this population have not yet been characterized. The present study aimed to identify factors associated with ALTP and examine its association with overall survival (OS) in patients receiving surgery followed by radiosurgery for MESCC. METHODS: Thirty-nine patients who underwent separation surgery followed by SSRS for MESCC were identified using a prospectively collected database and were retrospectively reviewed. Radiological measurements were collected from preoperative, postoperative, and post-SSRS MRI. Statistical analysis was conducted using the Kaplan-Meier product-limit method and Cox proportional hazards test. Subgroup analysis was conducted for patients who experienced ALTP into the epidural space (ALTP-E). RESULTS: The authors' cohort included 39 patients with a median OS of 14.7 months (range 2.07-96.3 months). ALTP was observed in 16 patients (41.0%) at a mean of 6.1 ± 5.4 months postradiosurgery, of whom 4 patients (10.3%) experienced ALTP-E. Patients with ALTP had shorter OS (13.0 vs 17.1 months, p = 0.047) compared with those without ALTP. Factors associated with an increased likelihood of ALTP included the amount of bone marrow infiltrated by tumor at the index level, amount of residual epidural disease following separation surgery, and prior receipt of radiotherapy at the index level (p < 0.05). Subgroup analysis revealed that primary tumor type, amount of preoperative epidural disease, time elapsed between surgery and radiosurgery, and prior receipt of radiotherapy at the index level were significantly associated with ALTP-E (p < 0.05). CONCLUSIONS: To the authors' knowledge, this study is the first to identify possible risk factors for ALTP, and they suggest that it may be associated with shorter OS in patients receiving surgery followed by radiosurgery for MESCC. Future studies with higher power should be conducted to further characterize factors associated with ALTP in this population.


Assuntos
Radiocirurgia , Compressão da Medula Espinal , Neoplasias da Coluna Vertebral , Espaço Epidural , Humanos , Estudos Retrospectivos , Compressão da Medula Espinal/cirurgia , Neoplasias da Coluna Vertebral/cirurgia
18.
Cogn Affect Behav Neurosci ; 20(1): 141-159, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31836960

RESUMO

The ventral pallidum (VP) is an important structure in processing reward. The VP may be the only brain structure where localized lesions in rats replace normal facial "liking" expressions to sweetness with excessive "disgust" reactions, such as gapes and chin rubs, that are normally reserved for unpalatable tastes. The posterior half of the VP (pVP) contains a hedonic hot spot where opioid or related neurochemical stimulations can amplify positive "liking" reactions to sweet taste. This is the same site where lesions or pharmacological inactivations replace positive hedonic reactions to sucrose with intense negative "disgust." In the present study, we aimed to identify brain networks recruited by pVP inactivation to generate excessive "disgust," using neuronal Fos expression as a marker of neurobiological activation. Microinjections in pVP of inhibitory GABAA/B agonists (muscimol and baclofen) caused rats to exhibit excessive "disgust" reactions to sucrose. Excessive "disgust" was accompanied by recruitment of neural Fos activation in several subcortical structures, including the posterior medial shell of nucleus accumbens (which also contains another GABAergic "disgust"-inducing "hedonic cold spot"), the bed nucleus of stria terminalis, lateral habenula, hypothalamus, and midbrain ventral tegmentum. Fos suppression was found in cortical limbic regions, including previously identified hedonic hot spots in the anteromedial orbitofrontal cortex and posterior insula. Finally, in addition to inducing excessive "disgust," pVP inactivation abolished motivational "wanting" to eat palatable food, reduced positive social interactions, and reordered sensorimotor relations. Our findings identify potential "disgust" generators in the brain that are released into excitation by pVP inhibition and may serve as targets for future research.


Assuntos
Mapeamento Encefálico , Núcleo Accumbens/metabolismo , Sacarose , Paladar/fisiologia , Animais , Asco , Ingestão de Alimentos/fisiologia , Agonistas de Receptores de GABA-A/farmacologia , Masculino , Neurônios/fisiologia , Ratos Sprague-Dawley , Recompensa , Sacarose/metabolismo , Sacarose/farmacologia , Paladar/efeitos dos fármacos
19.
Soft Matter ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32966528

RESUMO

A widely used method to measure the bending rigidity of bilayer membranes is fluctuation spectroscopy, which analyses the thermally-driven membrane undulations of giant unilamellar vesicles recorded with either phase-contrast or confocal microscopy. Here, we analyze the fluctuations of the same vesicle using both techniques and obtain consistent values for the bending modulus. We discuss the factors that may lead to discrepancies.

20.
Bull Entomol Res ; 110(4): 497-505, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32000866

RESUMO

Irradiation is a physical, environmentally friendly treatment which does not leave any residues in the product. It is increasingly used as an alternative to methyl bromide and other chemical fumigants for disinfestation of insect pest in stored grains. In this research, we try to evaluate the effect of low gamma irradiation doses in the range of 50-1200 Gy on the different stages of Callosobruchus maculatus. It was found that no adults emerged after irradiation of eggs at 450 Gy. No emerging adults (F1 generation) have been shown when larvae or pupae were exposed to 650 Gy. Also, no emerging adult has been shown from the parental C. maculatus adults irradiated with 650 Gy. When suppression of F1 generation was used for the measuring effective irradiation dose and phytosanitary efficacy, 650 Gy was required for disinfestation of cowpea seed weevils. The irradiation dose level of 650 Gy was used for the large-scale confirmatory tests applied to 27,754 adults of C. maculatus in cowpea seeds resulting in non F1 adults' production with a confidence level of 93.77%. All the physical and chemical characteristics of cowpea seeds were non-significantly (P ≤ 0.05) affected by the irradiation dose of 650 Gy. Meanwhile, this irradiation dose very slightly reduced the microbial load of cowpea seeds. We recommend the generic dose 650 Gy as the phytosanitary irradiation dose for the cowpea seed weevil.


Assuntos
Besouros/efeitos da radiação , Vigna/efeitos da radiação , Animais , Besouros/crescimento & desenvolvimento , Feminino , Raios gama/efeitos adversos , Controle de Insetos , Larva/efeitos da radiação , Masculino , Óvulo/efeitos da radiação , Pupa/efeitos da radiação , Sementes/efeitos da radiação
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