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1.
Front Psychiatry ; 14: 1225827, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37900288

RESUMO

We present the case of a 16-year-old female patient who experienced the loss of her mother to suicide, leading to post-traumatic stress disorder and prominent mood symptoms. She developed catatonic features during her inpatient psychiatric hospitalization following her own suicide attempt. Over her hospital course, she began to demonstrate signs of co-occurring obsessive-compulsive disorder (OCD) and affective psychotic disorder obfuscated by the severity of her catatonia. After initial workup including neurologic evaluation, laboratory tests, imaging (EEG, MRI), the patient was stabilized on a combination of benzodiazepines, antipsychotics, mood stabilizers, and selective serotonin reuptake inhibitors. The diagnostic challenges of disambiguating multiple concurrent diagnoses in the presence of a syndrome with unclear pathophysiology are discussed. Recommendations are made to thoroughly evaluate thought content during periods of catatonic remission to guide diagnosis and treatment.

2.
J Pediatr Hematol Oncol ; 34(3): 169-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22278200

RESUMO

Periodic blood exchange transfusion is a treatment modality commonly used to manage pediatric sickle cell anemia at the University of California Davis Medical Center. The goal of exchange transfusion therapy is to ameliorate vasoocclusion and improve tissue perfusion by removing sickled red blood cells and introducing normal red blood cells. Using computer-assisted intravital microscopy, pretransfusion and posttransfusion microvascular characteristics were analyzed. In this study, the bulbar conjunctiva exhibited a "blanched" avascular appearance in all 6 pediatric sickle cell anemia patients before transfusion, indicative of tissue hypoperfusion and ischemia. Immediately after transfusion, substantial improvement in vascularization and tissue perfusion resulted, reflected by the enhanced appearance of capillaries and arterioles. In addition, a decrease in red cell velocity was observed. These observations provide evidence that exchange transfusion therapy is beneficial in ameliorating vasoocclusion and improving tissue perfusion. However, with the paradoxical posttransfusion decrease in red cell velocity presumably due to induced hyperviscosity from the large transfusion volume, blood flow is still impaired. This decreased velocity may thwart efforts to improve oxygen delivery through transfusion and may, to some extent, promote vasoocclusion instead. This paradoxical result warrants further investigation on the effects of transfusion volume and viscosity in the exchange transfusion process.


Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/terapia , Transfusão Total , Microcirculação , Microscopia de Vídeo , Adolescente , Criança , Pré-Escolar , Humanos , Estudos Longitudinais , Prognóstico
3.
J Pathol Inform ; 13: 10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35136677

RESUMO

High-quality medical data is critical to the development and implementation of machine learning (ML) algorithms in healthcare; however, security, and privacy concerns continue to limit access. We sought to determine the utility of "synthetic data" in training ML algorithms for the detection of tuberculosis (TB) from inflammatory biomarker profiles. A retrospective dataset (A) comprised of 278 patients was used to generate synthetic datasets (B, C, and D) for training models prior to secondary validation on a generalization dataset. ML models trained and validated on the Dataset A (real) demonstrated an accuracy of 90%, a sensitivity of 89% (95% CI, 83-94%), and a specificity of 100% (95% CI, 81-100%). Models trained using the optimal synthetic dataset B showed an accuracy of 91%, a sensitivity of 93% (95% CI, 87-96%), and a specificity of 77% (95% CI, 50-93%). Synthetic datasets C and D displayed diminished performance measures (respective accuracies of 71% and 54%). This pilot study highlights the promise of synthetic data as an expedited means for ML algorithm development.

4.
Nat Commun ; 13(1): 2464, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513363

RESUMO

Transmission of epigenetic information between generations occurs in nematodes, flies and plants, mediated by specialised small RNA pathways, modified histones and DNA methylation. Similar processes in mammals can also affect phenotype through intergenerational or trans-generational mechanisms. Here we generate a luciferase knock-in reporter mouse for the imprinted Dlk1 locus to visualise and track epigenetic fidelity across generations. Exposure to high-fat diet in pregnancy provokes sustained re-expression of the normally silent maternal Dlk1 in offspring (loss of imprinting) and increased DNA methylation at the somatic differentially methylated region (sDMR). In the next generation heterogeneous Dlk1 mis-expression is seen exclusively among animals born to F1-exposed females. Oocytes from these females show altered gene and microRNA expression without changes in DNA methylation, and correct imprinting is restored in subsequent generations. Our results illustrate how diet impacts the foetal epigenome, disturbing canonical and non-canonical imprinting mechanisms to modulate the properties of successive generations of offspring.


Assuntos
Epigênese Genética , Impressão Genômica , Animais , Variação Biológica da População , Metilação de DNA , Dieta Hiperlipídica , Feminino , Mamíferos , Camundongos , Gravidez
5.
Am J Surg ; 221(2): 401-409, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33323275

RESUMO

BACKGROUND: There is global momentum to establish scalable Quality Improvement (QI) skills training curricula. We report development of an implementation plan for national scale-up of the 'Education in Quality Improvement' program (EQUIP) in UK urology residencies. MATERIALS & METHODS: Theory-of-Change (ToC) methodology was used, which engaged EQUIP stakeholders in developing a single-page implementation 'Logic Model' in 4 study phases (2 stakeholder workshops (N = 20); 10 stakeholder interviews). The framework method was used for analysis. RESULTS: Core elements of the EQUIP Logic Model include: (i) QI curriculum integration into national surgical curricula; (ii) resident-led, modular, team-based QI projects; (iii) development of a national web-platform as QI projects library; (iv) a train-the-trainers module to develop attendings as QI mentors; and (v) knowledge transfer activities (e.g., peer-reviewed publications of residents' QI projects). CONCLUSIONS: ToC methodology was useful in developing a stakeholder-driven, actionable implementation plan for the national scale-up of EQUIP in the UK.


Assuntos
Currículo , Internato e Residência/organização & administração , Avaliação de Programas e Projetos de Saúde/métodos , Melhoria de Qualidade/organização & administração , Urologia/educação , Competência Clínica , Humanos , Modelos Educacionais , Estudos Prospectivos , Pesquisa Qualitativa , Inquéritos e Questionários , Reino Unido
6.
Cancers (Basel) ; 13(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34208888

RESUMO

External factors, such as the coronavirus disease 2019 (COVID-19), can lead to cancellations and backlogs of cancer surgeries. The effects of these delays are unclear. This study summarised the evidence surrounding expectant management, delay radical prostatectomy (RP), and neoadjuvant hormone therapy (NHT) compared to immediate RP. MEDLINE and EMBASE was searched for randomised controlled trials (RCTs) and non-randomised controlled studies pertaining to the review question. Risks of biases (RoB) were evaluated using the RoB 2.0 tool and the Newcastle-Ottawa Scale. A total of 57 studies were included. Meta-analysis of four RCTs found overall survival and cancer-specific survival were significantly worsened amongst intermediate-risk patients undergoing active monitoring, observation, or watchful waiting but not in low- and high-risk patients. Evidence from 33 observational studies comparing delayed RP and immediate RP is contradictory. However, conservative estimates of delays over 5 months, 4 months, and 30 days for low-risk, intermediate-risk, and high-risk patients, respectively, have been associated with significantly worse pathological and oncological outcomes in individual studies. In 11 RCTs, a 3-month course of NHT has been shown to improve pathological outcomes in most patients, but its effect on oncological outcomes is apparently limited.

7.
Respir Physiol Neurobiol ; 164(3): 386-93, 2008 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-18822394

RESUMO

Mammalian cells require a constant O2 supply to produce adequate energy, and sustained hypoxia can kill cells. Mammals therefore have evolved sophisticated mechanisms to allow their cells to adapt to hypoxia. In this study, we investigated the role of TRP channels and the Na+-Ca2+ exchanger (NCX) in mediating hypoxia-induced [Ca2+]i elevation in a model of the O2-sensing rat pheochromocytoma (PC12) cell line by using Ca2+ imaging and molecular biological approaches. Non-selective cation channels, such as TRPC1, 3 and 6, were found to be functionally expressed in PC12 cells. They mediated Ca2+ entry when cells were exposed to acute hypoxia (PO2 of 15 mmHg), in addition to Ca2+ entry via VGCCs. Blockage of TRPCs by 2APB and SKF96365 could significantly reduce hypoxia-mediated [Ca2+]i elevation. Suramin and U73122 attenuated the hypoxia-induced [Ca2+]i elevation, implying the involvement of the G-protein and PLC pathways in the hypoxic response. In addition to TRPCs and VGCCs, NCX also contributed to the hypoxia-induced [Ca2+]i elevation, and blockade of NCX by KBR7943 could significantly decrease the hypoxia-induced [Ca2+]i elevation. Our results suggest that the activation of TRP by hypoxia could lead to NCX reversal; furthermore, membrane depolarization and TRPCs may play a primary role in mediating the hypoxic response in PC12 cells.


Assuntos
Cálcio/metabolismo , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Trocador de Sódio e Cálcio/fisiologia , Canais de Cátion TRPC/metabolismo , Animais , Compostos de Boro/farmacologia , Bloqueadores dos Canais de Cálcio , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Imidazóis/farmacologia , Modelos Biológicos , Células PC12/efeitos dos fármacos , Células PC12/metabolismo , Cloreto de Potássio/farmacologia , Ratos , Trocador de Sódio e Cálcio/antagonistas & inibidores , Suramina/farmacologia , Canais de Cátion TRPC/genética , Tioureia/análogos & derivados , Tioureia/farmacologia , Verapamil/farmacologia
8.
Respir Physiol Neurobiol ; 162(1): 18-23, 2008 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-18455484

RESUMO

[Ca(2+)](i) elevation is a key event when O(2) sensitive cells, e.g. PC12 cells and pulmonary artery smooth muscle cells, face hypoxia. Ca(2+) entry pathways in mediating hypoxia-induced [Ca(2+)](i) elevation include: voltage-gated Ca(2+) channels (VGCCs), transient receptor potential (TRP) channel and Na(+)-Ca(2+) ex-changer (NCX). In the pulmonary artery, accumulated evidence strongly suggests that prostaglandins (PGs) are involved in pulmonary inflammation and cause vasoconstriction during hypoxia. In this study, we investigated the effect of arachidonic acid (AA), the upstream substrate for PGs, on hypoxia response in O(2) sensitive cells. Exogenous application of AA significantly inhibited hypoxia-induced [Ca(2+)](i) elevation. This effect was due to AA itself rather than its degenerative products. The pharmacological modulation of endogenous AA showed that the prevention of AA generation by blockage of cPLA2, diacylglycerol (DAG) lipase and fatty acid hydrolysis (FAAH), augments hypoxia-induced [Ca(2+)](i) elevation, whereas prevention of AA degeneration attenuates hypoxia-induced [Ca(2+)](i) elevation. Over-expression of COX2 enhances hypoxia-induced [Ca(2+)](i) elevation and this enhancement is reversed by exogenous AA. Our results suggest that AA inhibits hypoxia response. The dynamic alterations in cellular lipids might determine cell response to hypoxia.


Assuntos
Ácido Araquidônico/farmacologia , Cálcio/metabolismo , Hipóxia/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Células PC12/efeitos dos fármacos , Artéria Pulmonar/citologia , Animais , Cálcio/farmacologia , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Cloreto de Potássio/farmacologia , Ratos
9.
Expert Rev Anticancer Ther ; 17(12): 1159-1168, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28933973

RESUMO

INTRODUCTION: With level 1 evidence now available on the diagnostic accuracy of multiparametric magnetic resonance imaging (MRI) we must now utilise this data in developing an MRI-stratified diagnostic pathway for the early detection of prostate cancer. Areas covered: A literature review was conducted and identified seven randomised control trials (RCT's) assessing the diagnostic accuracy of such a pathway against the previously accepted systematic/random trans-rectal ultrasound guided (TRUS) biopsy pathway. The studies were heterogeneous in their design. Five studies assessed the addition of MRI-targeted biopsies to a standard care systematic TRUS biopsy pathway. Three of these studies showed either an increase in their diagnostic accuracy or the potential to remove systematic biopsies. Two studies looked specifically at a targeted biopsy only pathway and although the results were again mixed, there was no decrease in the diagnostic rate and overall significantly fewer biopsy cores were taken in the MRI group. Expert commentary: Results from these RCT's together with multiple retrospective and prospective studies point towards either an improved diagnostic rate for clinically significant cancer and/or a reduction in the need for systematic biopsies with a MRI-stratified pathway. The challenge for the urological community will be to implement pre-biopsy MRI into a routine clinical pathway with likely independent monitoring of standards.


Assuntos
Detecção Precoce de Câncer/métodos , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Animais , Humanos , Biópsia Guiada por Imagem/métodos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Ultrassonografia de Intervenção/métodos
10.
Cell Rep ; 18(5): 1090-1099, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28147266

RESUMO

Imprinted genes are regulated according to parental origin and can influence embryonic growth and metabolism and confer disease susceptibility. Here, we designed sensitive allele-specific reporters to non-invasively monitor imprinted Cdkn1c expression in mice and showed that expression was modulated by environmental factors encountered in utero. Acute exposure to chromatin-modifying drugs resulted in de-repression of paternally inherited (silent) Cdkn1c alleles in embryos that was temporary and resolved after birth. In contrast, deprivation of maternal dietary protein in utero provoked permanent de-repression of imprinted Cdkn1c expression that was sustained into adulthood and occurred through a folate-dependent mechanism of DNA methylation loss. Given the function of imprinted genes in regulating behavior and metabolic processes in adults, these results establish imprinting deregulation as a credible mechanism linking early-life adversity to later-life outcomes. Furthermore, Cdkn1c-luciferase mice offer non-invasive tools to identify factors that disrupt epigenetic processes and strategies to limit their long-term impact.


Assuntos
Inibidor de Quinase Dependente de Ciclina p57/metabolismo , Impressão Genômica/fisiologia , Alelos , Animais , Cromatina/fisiologia , Metilação de DNA/fisiologia , Epigênese Genética/fisiologia , Camundongos
11.
Clin Hemorheol Microcirc ; 47(2): 131-41, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21339633

RESUMO

We hypothesized that T2DM vasculopathy can be revealed and quantified in the bulbar conjunctiva prior to its pathologic presentation in the retina. Using computer-assisted intravital microscopy (CAIM), an objective, non-invasive approach can provide a viable complement to retinal fundus photography to possibly screen patients for early signs of real-time, in vivo T2DM vasculopathy. Fundus photography was utilized to determine the retinopathy level (RL) in T2DM patients with non-proliferative diabetic retinopathy (NPDR) and control subjects. CAIM was used to quantify microangiopathy in the bulbar conjunctiva in the same patients, and reported on a severity index (SI). The average RL for the T2DM patients in this study is 19.68 ± 9.91, which differs from control subjects (RL = 10 ± 0.0; p < 0.05). A significant difference in vasculopathy was observed in the conjunctival microcirculation in the same patients (SI = 5.81 ± 1.30) when compared with control subjects (SI = 1.33 ± 1.58; p < 0.05). The results provide evidence that significant vasculopathy had developed in the microcirculation in the bulbar conjunctiva, though diabetic retinopathy had not developed significantly in the same patients - indicative of the presence of a time window for early intervention of T2DM before non-proliferative retinopathy develops, and the real-time availability of the conjunctival microvasculature as an in vivo platform to monitor disease progression.


Assuntos
Túnica Conjuntiva/irrigação sanguínea , Túnica Conjuntiva/patologia , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/diagnóstico , Retinopatia Diabética/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Microcirculação , Microscopia/métodos , Pessoa de Meia-Idade , Adulto Jovem
12.
J Cell Physiol ; 213(1): 79-87, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17477379

RESUMO

Arterial smooth muscle cells exhibit vasomotion, related to oscillations in intracellular Ca(2+) concentration, but the origin and function of these has not yet been fully determined. We measured intracellular Ca(2+) using conventional fluorescent methods in primary cultured, human umbilical cord artery smooth muscle cells (HUCASMC). Spontaneous oscillations in Ca(2+) was found in only 1% of all cells but exogenous, micromolar concentrations of ATP could induce Ca(2+) oscillations in 70% of cells with the most common pattern being one of regular amplitude and frequency with a return to basal levels between each peak. The P2Y agonist, UTP, but not the P2X agonist alphabeta-methylene ATP, could also induce Ca(2+) oscillations. Once induced, these oscillations could not be blocked by G-protein, PLC, VGCC or TRP channel antagonists applied individually, but could be prevented when antagonists were applied together. In the presence of EGTA, micromolar concentrations of ATP induced an elevation in intracellular Ca(2+) but did not induce Ca(2+) oscillations. The oscillation frequency induced by ATP was affected by bath Ca(2+) concentration. Taken together, these data suggest that external Ca(2+) entry maintains the Ca(2+) oscillation induced by activation of P2Y receptors. Once induced, multiple mechanisms are involved to maintain the oscillation and the oscillation frequency is determined by the speed of Ca(2+) refilling. Chronic hypoxia enhanced the Ca(2+) response and altered the oscillation frequency. We suggest that these oscillations may play a role in the maintenance of umbilical blood flow during situations in which GPCR are activated.


Assuntos
Trifosfato de Adenosina/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Trifosfato de Adenosina/análogos & derivados , Ácido Araquidônico/farmacologia , Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Células Cultivadas , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Agonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2/classificação , Receptores Purinérgicos P2/metabolismo , Uridina Trifosfato/farmacologia
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