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1.
Curr Opin Pediatr ; 32(1): 192-197, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31789977

RESUMO

PURPOSE OF REVIEW: Sextortion is defined as the act of coercing people into sending explicit images of themselves and subsequently blackmailing victims with the public release of said images. Prosecutions of sextortion cases involving minors have increased almost two-fold in the past 5 years. The purpose of this review is to explore the literature regarding the behavior of both victims and perpetrators, the effects on victims, and the support resources available for clinicians, victims, and parents. RECENT FINDINGS: Sextortion begins as an unassuming request for personal pictures and quickly escalates. Minors targeted by predators fear both punishment by guardians and the social consequences that follow the release of their explicit pictures. This cycle of victimization endangers minors and may lead to mental health problems, such as anxiety and depression. Recently, sextortion cases have risen to the forefront of national attention through the mainstream media with celebrities revealed as both perpetrators and victims. This higher visibility of sextortion highlights the importance of reviewing recent research regarding minors and their online behavior and the tactics of perpetrators. SUMMARY: Sextortion, an extreme form of cyber abuse, endangers minors and may lead to anxiety and depression. Pediatricians should be familiar with the concept of sextortion and discuss its dangers and available resources with parents and minors.

2.
Bariatr Surg Pract Patient Care ; 14(3): 113-119, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31572626

RESUMO

Background/Objectives: A history of physical and sexual abuse has been implicated in weight gain. Although bariatric surgery is effective for weight loss in severely obese individuals, we investigated whether bariatric surgery patients who self-report a history of physical and/or sexual abuse have differential outcomes regarding weight loss, body mass index (BMI), quality of life (SF-36), and depressive symptoms (Center for Epidemiologic Studies Depression [CESD]) compared with nonabused patients. Materials and Methods: Standardized assessments at baseline and follow-up visits were performed on 103 obese (BMI >35) female bariatric surgery patients (mean age: 44.11 years, standard deviation: 11.67 years). Results: In total 49.5% of participants reported abuse. Abused group had significantly higher BMI (p < 0.01) and depression scores (p < 0.01). After surgery, the BMI between the two groups was no longer significantly different, although the abused group remained significantly more depressed. Mixed models showed that abuse was associated with CESD scores (p < 0.01) and SF-36 mental composite scores (p = 0.03) after adjusting for smoking history. Conclusion: Bariatric surgery leads to a better weight loss in abused patients. Abuse history might be an additional factor for clinicians to consider when advising bariatric surgery, as our study suggests that women with history of abuse may have a higher weight loss benefit but less mental health improvement from the intervention.

3.
Soft Matter ; 15(23): 4689-4702, 2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31119245

RESUMO

Many clays, soils, biological tissues, foods, and coatings are shrinkable, granular materials: they are composed of packed, hydrated grains that shrink when dried. In many cases, these packings crack during drying, critically hindering applications. However, while cracking has been widely studied for bulk gels and packings of non-shrinkable grains, little is known about how packings of shrinkable grains crack. Here, we elucidate how grain shrinkage alters cracking during drying. Using experiments with model shrinkable hydrogel beads, we show that differential shrinkage can dramatically alter crack evolution during drying-in some cases, even causing cracks to spontaneously "self-close". In other cases, packings shrink without cracking or crack irreversibly. We developed both granular and continuum models to quantify the interplay between grain shrinkage, poromechanics, packing size, drying rate, capillarity, and substrate friction on cracking. Guided by the theory, we also found that cracking can be completely altered by varying the spatial profile of drying. Our work elucidates the rich physics underlying cracking in shrinkable, granular packings, and yields new strategies for controlling crack evolution.

4.
Soft Matter ; 15(17): 3620-3626, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30973562

RESUMO

Diverse applications-ranging from enhanced oil recovery, filtration, and lab on a chip sorting-rely on the flow-induced transport of deformable particles in porous media. However, how fluid flow can force such particles to squeeze through pore constrictions of complex geometries is poorly understood. Here, we study the transport of model deformable particles in millifluidic porous media with constrictions of tunable aspect ratio. We find that multiple particles can unexpectedly squeeze through large-aspect ratio constrictions, even when isolated particles cannot. This phenomenon arises from pairwise flow-mediated interactions between the particles: when one particle is trapped at a constriction, the increased fluid flow around it enables a second to squeeze past due to locally increased hydrodynamic stresses. This cooperative mechanism causes the particles to ultimately sort themselves by size through the pore space. By revealing a new mode of deformable particle transport in porous media, our work helps to inform real-world applications and provides a straightforward way to sort particles based on size.

5.
Proc Natl Acad Sci U S A ; 115(19): 4833-4838, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29686067

RESUMO

Finger-like protrusions that form along fluid-fluid displacement fronts in porous media are often excited by hydrodynamic instability when low-viscosity fluids displace high-viscosity resident fluids. Such interfacial instabilities are undesirable in many natural and engineered displacement processes. We report a phenomenon whereby gradual and monotonic variation of pore sizes along the front path suppresses viscous fingering during immiscible displacement, that seemingly contradicts conventional expectation of enhanced instability with pore size variability. Experiments and pore-scale numerical simulations were combined with an analytical model for the characteristics of displacement front morphology as a function of the pore size gradient. Our results suggest that the gradual reduction of pore sizes act to restrain viscous fingering for a predictable range of flow conditions (as anticipated by gradient percolation theory). The study provides insights into ways for suppressing unwanted interfacial instabilities in porous media, and provides design principles for new engineered porous media such as exchange columns, fabric, paper, and membranes with respect to their desired immiscible displacement behavior.

6.
ACS Chem Biol ; 11(1): 200-10, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26502114

RESUMO

Proteostasis in the cytosol is governed by the heat shock response. The master regulator of the heat shock response, heat shock factor 1 (HSF1), and key chaperones whose levels are HSF1-regulated have emerged as high-profile targets for therapeutic applications ranging from protein misfolding-related disorders to cancer. Nonetheless, a generally applicable methodology to selectively and potently inhibit endogenous HSF1 in a small molecule-dependent manner in disease model systems remains elusive. Also problematic, the administration of even highly selective chaperone inhibitors often has the side effect of activating HSF1 and thereby inducing a compensatory heat shock response. Herein, we report a ligand-regulatable, dominant negative version of HSF1 that addresses these issues. Our approach, which required engineering a new dominant negative HSF1 variant, permits dosable inhibition of endogenous HSF1 with a selective small molecule in cell-based model systems of interest. The methodology allows us to uncouple the pleiotropic effects of chaperone inhibitors and environmental toxins from the concomitantly induced compensatory heat shock response. Integration of our method with techniques to activate HSF1 enables the creation of cell lines in which the cytosolic proteostasis network can be up- or down-regulated by orthogonal small molecules. Selective, small molecule-mediated inhibition of HSF1 has distinctive implications for the proteostasis of both chaperone-dependent globular proteins and aggregation-prone intrinsically disordered proteins. Altogether, this work provides critical methods for continued exploration of the biological roles of HSF1 and the therapeutic potential of heat shock response modulation.


Assuntos
Proteínas de Ligação a DNA/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Fatores de Transcrição de Choque Térmico , Humanos , Immunoblotting , Análise em Microsséries , Reação em Cadeia da Polimerase em Tempo Real , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
J Neurosurg Anesthesiol ; 26(4): 306-12, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24487732

RESUMO

BACKGROUND: During spinal surgery, intraoperative monitoring of motor-evoked potentials (MEPs) is a useful means of assessing the intraoperative integrity of corticospinal pathways. However, MEPs are known to be particularly sensitive to the suppressive effects of inhalational halogenated anesthetic agents. OBJECTIVE: To investigate the effects of increasing end-tidal concentrations of desflurane and sevoflurane anesthesia in a background of propofol and remifentanil with multipulse cortical stimulation on intraoperative monitoring of MEPs. METHODS: In this randomized crossover trial, 14 consecutive patients (7 in each arm) undergoing major spine surgery, under a background anesthetic of propofol (75 to 125 mcg/kg/min) and remifentanil (0.1 to 0.2 mcg/kg/min), were randomly assigned to receive the sequence of inhalational agents studied: either DES-SEVO (desflurane followed by sevoflurane); or SEVO-DES (sevoflurane followed by desflurane). Multiples (0.3, 0.5, and 0.7) of minimum alveolar concentration (MAC) of desflurane and sevoflurane were administered. After a washout period of 15 minutes using high fresh oxygen/air flows, each of the patients then received the other gas as the second agent. Cortical stimulation was achieved with a train of 5 equivalent square pulses, each 0.05 ms in duration, delivered at 2 ms intervals. MEP recordings were made in the upper limb (UL) from first dorsal interosseus and lower limb (LL) from tibialis anterior with subdermal needle electrodes. RESULTS: At 0.3 MAC desflurane, there was no statistical significant difference in transcranial-evoked MEP amplitudes from the baseline in both UL and LL stimulation. However, this was not the case for sevoflurane for which even a low concentration at 0.3 MAC significantly depressed MEP amplitudes of LL (but not UL) from baseline value. Desflurane at 0.5 and 0.7 MAC depresses LL MEP to 58.4% and 59.9% of baseline, respectively (P<0.05), whereas sevoflurane at 0.3, 0.5, and 0.7 MAC depresses LL MEP to 66.2%, 41.3%, and 25.3% of baseline, respectively (P<0.05). There was no difference in latency of the responses at any MAC. CONCLUSIONS: Inhalational anesthetic agents (sevoflurane >desflurane) suppress MEP amplitudes in a dose-dependent manner. The use of 0.3 MAC of desflurane (but not sevoflurane) provided good MEP recordings acceptable for clinical interpretation for both upper and LLs. The LL appears to be more sensitive to anesthetic-induced depression compared with the UL. All patients studied had normal neurological examination hence, these results may not be applicable to those with preexisting deficits.


Assuntos
Anestésicos Inalatórios/farmacologia , Potencial Evocado Motor/efeitos dos fármacos , Isoflurano/análogos & derivados , Éteres Metílicos/farmacologia , Monitorização Intraoperatória/métodos , Monitorização Intraoperatória/estatística & dados numéricos , Adolescente , Adulto , Anestésicos Intravenosos , Estudos Cross-Over , Desflurano , Relação Dose-Resposta a Droga , Feminino , Humanos , Isoflurano/farmacologia , Masculino , Pessoa de Meia-Idade , Piperidinas , Propofol , Remifentanil , Sevoflurano , Coluna Vertebral/cirurgia , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
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