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1.
Acta Neuropathol ; 147(1): 17, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38231266

RESUMO

Definitive diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) relies on the examination of brain tissues for the pathological prion protein (PrPSc). Our previous study revealed that PrPSc-seeding activity (PrPSc-SA) is detectable in skin of sCJD patients by an ultrasensitive PrPSc seed amplification assay (PrPSc-SAA) known as real-time quaking-induced conversion (RT-QuIC). A total of 875 skin samples were collected from 2 cohorts (1 and 2) at autopsy from 2-3 body areas of 339 cases with neuropathologically confirmed prion diseases and non-sCJD controls. The skin samples were analyzed for PrPSc-SA by RT-QuIC assay. The results were compared with demographic information, clinical manifestations, cerebrospinal fluid (CSF) PrPSc-SA, other laboratory tests, subtypes of prion diseases defined by the methionine (M) or valine (V) polymorphism at residue 129 of PrP, PrPSc types (#1 or #2), and gene mutations in deceased patients. RT-QuIC assays of the cohort #1 by two independent laboratories gave 87.3% or 91.3% sensitivity and 94.7% or 100% specificity, respectively. The cohort #2 showed sensitivity of 89.4% and specificity of 95.5%. RT-QuIC of CSF available from 212 cases gave 89.7% sensitivity and 94.1% specificity. The sensitivity of skin RT-QuIC was subtype dependent, being highest in sCJDVV1-2 subtype, followed by VV2, MV1-2, MV1, MV2, MM1, MM1-2, MM2, and VV1. The skin area next to the ear gave highest sensitivity, followed by lower back and apex of the head. Although no difference in brain PrPSc-SA was detected between the cases with false negative and true positive skin RT-QuIC results, the disease duration was significantly longer with the false negatives [12.0 ± 13.3 (months, SD) vs. 6.5 ± 6.4, p < 0.001]. Our study validates skin PrPSc-SA as a biomarker for the detection of prion diseases, which is influenced by the PrPSc types, PRNP 129 polymorphisms, dermatome sampled, and disease duration.


Assuntos
Síndrome de Creutzfeldt-Jakob , Doenças Priônicas , Príons , Humanos , Príons/genética , Doenças Priônicas/diagnóstico , Doenças Priônicas/genética , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/genética , Biomarcadores
2.
Ann Surg Oncol ; 31(4): 2391-2400, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38270826

RESUMO

BACKGROUND: Normal carcinoembryonic antigen (CEA) levels (≤ 2.5 ng/ml) after resection of localized colorectal cancer or liver metastases are associated with improved survival, however, these trends are understudied for colorectal peritoneal metastases (CRPM). PATIENTS AND METHODS: We conducted a retrospective single-institution study of patients with CRPM undergoing cytoreductive surgery with hyperthermic intraperitoneal chemoperfusion (CRS/HIPEC) with and without neoadjuvant chemotherapy (NACT). CEA was measured before and after NACT and within 3 months after CRS/HIPEC. RESULTS: A total of 253 patients (mean age 55.3 years) with CRPM undergoing CRS/HIPEC had complete CEA data and 191 also underwent NACT with complete data. The median peritoneal carcinomatosis index score (PCI) of the overall cohort was 12 and 82.7% of patients had complete cytoreduction (CC0). In total, 64 (33.5%) patients had normal CEA levels after NACT with a median overall survival (OS) of 45.2 months compared with those with an elevated CEA (26.4 months, p = 0.004). Patients with normal CEA after NACT had a lower PCI found at the time of surgery than those with elevated CEA (10 versus 14, p < 0.001), 68 (26.9%) patients with an elevated preoperative CEA level experienced normalization after CRS/HIPEC, and 118 (46.6%) patients had elevated CEA after CRS/HIPEC. Patients who experienced normalization demonstrated similar OS to patients that had normal CEA levels pre- and post-surgery and improved OS compared with those with elevated postop CEA (median 41.9 versus 47 months versus 17.1 months, respectively, p < 0.001). CONCLUSIONS: Normal CEA levels after NACT and/or CRS/HIPEC are associated with improved survival for patients with CRPM. Patients that normalize CEA levels after surgery have similar survival to those with normal preoperative levels.


Assuntos
Neoplasias Colorretais , Hipertermia Induzida , Neoplasias Peritoneais , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Procedimentos Cirúrgicos de Citorredução , Antígeno Carcinoembrionário , Neoplasias Colorretais/patologia , Neoplasias Peritoneais/secundário , Estudos Retrospectivos , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Taxa de Sobrevida
3.
Arch Rehabil Res Clin Transl ; 5(3): 100279, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37744198

RESUMO

Objective: The objective was to compare task performance in individuals with upper limb impairments with and without a myoelectric arm orthosis. Design: Three-month observational study. Participants met at 4 time points after receiving their myoelectric orthosis (2-Weeks, Month-1, Month-2, Month-3) to complete 4 standardized common daily tasks. Setting: Nationwide sessions completed remotely over videoconference calls at home. There were no specific clinic affiliations. Participants: Adults with upper limb impairment due to stroke who were in the process of being fit with a myoelectric arm orthosis as a first-time user. Interventions: The orthosis was a custom-fabricated myoelectric arm orthosis called the MyoPro®. Main Outcome Measures: Functional tasks were completed at each session with and without the MyoPro. Participants were evaluated on their success and the time required to complete each functional task. Longitudinal mixed and longitudinal mixed logistic regression models were analyzed. Results: Eighteen individuals with chronic arm weakness due to stroke were included in the analysis. Statistically significant and clinically meaningful improvements were observed on the functional tasks in the participants' homes. By 3 months, participants successfully used the MyoPro to accomplish the tasks, reduced the amount of time spent to complete the tasks, and had a higher probability of success as compared with at 2 weeks. With the MyoPro, participants showed significant improvement in overall task completion and completed the tasks in a significantly decreased time as compared with without the MyoPro. Conclusions: The MyoPro provides a stabilizing support to the weak arm of individuals after stroke and enables individuals to use their impaired arm to complete functional tasks independently in the home environment.

4.
JCO Clin Cancer Inform ; 7: e2300078, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37738540

RESUMO

PURPOSE: The gold standard for monitoring response status in patients with multiple myeloma (MM) is serum and urine protein electrophoresis which quantify M-spike proteins; however, the turnaround time for results is 3-7 days which delays treatment decisions. We hypothesized that machine learning (ML) could integrate readily available clinical and laboratory data to rapidly and accurately predict patient M-spike values. METHODS: A retrospective chart review was performed using the deidentified, electronic medical records of 171 patients with MM. RESULTS: Random forest (RF) analysis identified the weighted value of each independent variable (N = 43) integrated into the ML algorithm. Pearson and Spearman coefficients indicated that the ML-predicted M-spike values correlated highly with laboratory-measured serum protein electrophoresis values. Feature selected RF modeling revealed that only two variables-the first lagged M-spike and serum total protein-accurately predicted the M-spike. CONCLUSION: Taken together, our results demonstrate the feasibility and prognostic potential of ML tools that integrate electronic data to longitudinally monitor disease burden. ML tools support the seamless, secure exchange of patient information to expedite and personalize clinical decision making and overcome geographic, financial, and social barriers that currently limit the access of underserved populations to cancer care specialists so that the benefits of medical progress are not limited to selected groups.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/terapia , Sistemas Automatizados de Assistência Junto ao Leito , Estudos Retrospectivos , Algoritmos , Aprendizado de Máquina
5.
Struct Heart ; 7(4): 100182, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37520136

RESUMO

Background: Inflammation and thrombosis are often linked mechanistically and are associated with adverse events after transcatheter aortic valve replacement (TAVR). High residual platelet reactivity (HRPR) is especially common when clopidogrel is used in this setting, but its relevance to immune activation is unknown. We sought to determine whether residual activity at the purinergic receptor P2Y12 (P2Y12) promotes prothrombotic immune activation in the setting of TAVR. Methods: This was a randomized trial of 60 patients (enrolled July 2015 through December 2018) assigned to clopidogrel (300mg load, 75mg daily) or ticagrelor (180mg load, 90 mg twice daily) before and for 30 days following TAVR. Co-primary endpoints were P2Y12-dependent platelet activity (Platelet Reactivity Units; VerifyNow) and the proportion of inflammatory (cluster of differentiation [CD] 14+/CD16+) monocytes 1 day after TAVR. Results: Compared to clopidogrel, those randomized to ticagrelor had greater platelet inhibition (median Platelet Reactivity Unit [interquartile range]: (234 [170.0-282.3] vs. 128.5 [86.5-156.5], p < 0.001), but similar inflammatory monocyte proportions (22.2% [18.0%-30.2%] vs. 25.1% [22.1%-31.0%], p = 0.201) 1 day after TAVR. Circulating monocyte-platelet aggregates, soluble CD14 levels, interleukin 6 and 8 levels, and D-dimers were also similar across treatment groups. HRPR was observed in 63% of the clopidogrel arm and was associated with higher inflammatory monocyte proportions. Major bleeding events, pacemaker placement, and mortality did not differ by treatment assignment. Conclusions: Residual P2Y12 activity after TAVR is common in those treated with clopidogrel but ticagrelor does not significantly alter biomarkers of prothrombotic immune activation. HRPR appears to be an indicator (not a cause) of innate immune activation in this setting.

6.
Nat Commun ; 14(1): 3823, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380658

RESUMO

Pancreatic Ductal Adenocarcinoma (PDAC) is highly resistant to chemotherapy. Effective alternative therapies have yet to emerge, as chemotherapy remains the best available systemic treatment. However, the discovery of safe and available adjuncts to enhance chemotherapeutic efficacy can still improve survival outcomes. We show that a hyperglycemic state substantially enhances the efficacy of conventional single- and multi-agent chemotherapy regimens against PDAC. Molecular analyses of tumors exposed to high glucose levels reveal that the expression of GCLC (glutamate-cysteine ligase catalytic subunit), a key component of glutathione biosynthesis, is diminished, which in turn augments oxidative anti-tumor damage by chemotherapy. Inhibition of GCLC phenocopies the suppressive effect of forced hyperglycemia in mouse models of PDAC, while rescuing this pathway mitigates anti-tumor effects observed with chemotherapy and high glucose.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Administração Cutânea , Glucose , Neoplasias Pancreáticas
7.
Acta Neuropathol ; 146(1): 31-50, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37154939

RESUMO

Tau neurofibrillary tangles are a hallmark of Alzheimer's disease neuropathological change. However, it remains largely unclear how distinctive Alzheimer's disease tau seeds (i.e. 3R/4R) correlate with histological indicators of tau accumulation. Furthermore, AD tau co-pathology is thought to influence features and progression of other neurodegenerative diseases including Lewy body disease; yet measurements of different types of tau seeds in the setting of such diseases is an unmet need. Here, we use tau real-time quaking-induced conversion (RT-QuIC) assays to selectively quantitate 3R/4R tau seeds in the frontal lobe which accumulates histologically identifiable tau pathology at late disease stages of AD neuropathologic change. Seed quantitation across a spectrum of neurodegenerative disease cases and controls indicated tau seeding activity can be detected well before accompanying histopathological indication of tau deposits, and even prior to the earliest evidence of Alzheimer's-related tau accumulation anywhere in the brain. In later stages of AD, 3R/4R tau RT-QuIC measures correlated with immunohistochemical tau burden. In addition, Alzheimer's tau seeds occur in the vast majority of cases evaluated here inclusive of primary synucleinopathies, frontotemporal lobar degeneration and even controls albeit at multi-log lower levels than Alzheimer's cases. α-synuclein seeding activity confirmed synucleinopathy cases and further indicated the co-occurrence of α-synuclein seeds in some Alzheimer's disease and primary tauopathy cases. Our analysis indicates that 3R/4R tau seeds in the mid-frontal lobe correlate with the overall Braak stage and Alzheimer's disease neuropathologic change, supporting the quantitative predictive value of tau RT-QuIC assays. Our data also indicate 3R/4R tau seeds are elevated in females compared to males at high (≥ IV) Braak stages. This study suggests 3R/4R tau seeds are widespread even prior to the earliest stages of Alzheimer's disease changes, including in normal, and even young individuals, with prevalence across multiple neurodegenerative diseases to further define disease subtypes.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Sinucleinopatias , Tauopatias , Feminino , Humanos , Masculino , alfa-Sinucleína , Doença de Alzheimer/patologia , Proteínas tau , Tauopatias/patologia
8.
Pediatr Res ; 94(4): 1444-1450, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37188801

RESUMO

BACKGROUND: Intermittent hypoxemia (IH) events are common in preterm neonates and are associated with adverse outcomes. Animal IH models can induce oxidative stress. We hypothesized that an association exists between IH and elevated peroxidation products in preterm neonates. METHODS: Time in hypoxemia, frequency of IH, and duration of IH events were assessed from a prospective cohort of 170 neonates (<31 weeks gestation). Urine was collected at 1 week and 1 month. Samples were analyzed for lipid, protein, and DNA oxidation biomarkers. RESULTS: At 1 week, adjusted multiple quantile regression showed positive associations between several hypoxemia parameters with various individual quantiles of isofurans, neurofurans, dihomo-isoprostanes, dihomo-isofurans, and ortho-tyrosine and a negative correlation with dihomo-isoprostanes and meta-tyrosine. At 1 month, positive associations were found between several hypoxemia parameters with quantiles of isoprostanes, dihomo-isoprostanes and dihomo-isofurans and a negative correlation with isoprostanes, isofurans, neuroprostanes, and meta-tyrosine. CONCLUSIONS: Preterm neonates experience oxidative damage to lipids, proteins, and DNA that can be analyzed from urine samples. Our single-center data suggest that specific markers of oxidative stress may be related to IH exposure. Future studies are needed to better understand mechanisms and relationships to morbidities of prematurity. IMPACT: Hypoxemia events are frequent in preterm infants and are associated with poor outcomes. The mechanisms by which hypoxemia events result in adverse neural and respiratory outcomes may include oxidative stress to lipids, proteins, and DNA. This study begins to explore associations between hypoxemia parameters and products of oxidative stress in preterm infants. Oxidative stress biomarkers may assist in identifying high-risk neonates.


Assuntos
Recém-Nascido Prematuro , Isoprostanos , Lactente , Animais , Humanos , Recém-Nascido , Estudos Prospectivos , Hipóxia , Estresse Oxidativo , Biomarcadores/urina , DNA
9.
Pediatr Res ; 94(4): 1436-1443, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37188799

RESUMO

BACKGROUND: Hypoxemia is a physiological manifestation of immature respiratory control in preterm neonates, which is likely impacted by neurotransmitter imbalances. We investigated relationships between plasma levels of the neurotransmitter serotonin (5-HT), metabolites of tryptophan (TRP), and parameters of hypoxemia in preterm neonates. METHODS: TRP, 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), and kynurenic acid (KA) were analyzed in platelet-poor plasma at ~1 week and ~1 month of life from a prospective cohort of 168 preterm neonates <31 weeks gestational age (GA). Frequency of intermittent hypoxemia (IH) events and percent time hypoxemic (<80%) were analyzed in a 6 h window after the blood draw. RESULTS: At 1 week, infants with detectable plasma 5-HT had fewer IH events (OR (95% CI) = 0.52 (0.29, 0.31)) and less percent time <80% (OR (95% CI) = 0.54 (0.31, 0.95)) compared to infants with undetectable 5-HT. A similar relationship occurred at 1 month. At 1 week, infants with higher KA showed greater percent time <80% (OR (95% CI) = 1.90 (1.03, 3.50)). TRP, 5-HIAA or KA were not associated with IH frequency at either postnatal age. IH frequency and percent time <80% were positively associated with GA < 29 weeks. CONCLUSIONS: Circulating neuromodulators 5-HT and KA might represent biomarkers of immature respiratory control contributing to hypoxemia in preterm neonates. IMPACT: Hypoxemia events are frequent in preterm infants and are associated with poor outcomes. Mechanisms driving hypoxemia such as immature respiratory control may include central and peripheral imbalances in modulatory neurotransmitters. This study found associations between the plasma neuromodulators serotonin and kynurenic acid and parameters of hypoxemia in preterm neonates. Imbalances in plasma biomarkers affecting respiratory control may help identify neonates at risk of short- and long-term adverse outcomes.


Assuntos
Recém-Nascido Prematuro , Serotonina , Lactente , Humanos , Recém-Nascido , Serotonina/metabolismo , Estudos Prospectivos , Ácido Hidroxi-Indolacético , Ácido Cinurênico , Hipóxia , Triptofano , Biomarcadores , Neurotransmissores
10.
Am J Trop Med Hyg ; 109(1): 105-114, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37217165

RESUMO

Hepatitis B virus (HBV) infection is a major public health problem in Sierra Leone, yet reliable estimates of cases are lacking. This study aimed to provide an estimate of the national prevalence of chronic HBV infection in the general population and select groups in Sierra Leone. We used the electronic databases PubMed/MEDLINE, Embase, Scopus, ScienceDirect, Web of Science, Google Scholar, and African Journals Online to systematically review articles reporting hepatitis B infection surface antigen seroprevalence estimates in Sierra Leone during 1997-2022. We estimated pooled HBV seroprevalence rates and assessed potential sources of heterogeneity. Of 546 publications screened, 22 studies with a total sample size of 107,186 people were included in the systematic review and meta-analysis. The pooled prevalence of chronic HBV infection was 13.0% (95% CI, 10.0-16.0) (I2 = 99%; Pheterogeneity < 0.01). During the study period, the HBV prevalence rates were as follows: 17.9% (95% CI, 6.7-39.8) before 2015, 13.3% (95% CI, 10.4-16.9) during 2015-2019, and 10.7% (95% CI, 7.5-14.9) during 2020-2022. The use of the 2020-2022 HBV prevalence estimates corresponded to 870,000 cases of chronic HBV infection (uncertainty interval, 610,000-1,213,000), or approximately one in nine people. The highest HBV seroprevalence estimates were among adolescents aged 10-17 years (17.0%; 95% CI, 8.8-30.5), Ebola survivors (36.8%; 95% CI, 26.2-48.8), people living with HIV (15.9%; 95% CI, 10.6-23.0), and those in the Northern Province (19.0%; 95% CI, 6.4-44.7) and Southern Province (19.7%; 95% CI, 10.9-32.8) regions. These findings may help inform national HBV program implementation in Sierra Leone.


Assuntos
Hepatite B Crônica , Hepatite B , Adolescente , Humanos , Hepatite B Crônica/epidemiologia , Estudos Soroepidemiológicos , Prevalência , Serra Leoa/epidemiologia , Hepatite B/epidemiologia , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B
11.
Clin Infect Dis ; 77(2): 272-279, 2023 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-37011013

RESUMO

BACKGROUND: People with human immunodeficiency virus (PWH) are at increased risk for comorbidities, and plasma interleukin 6 (IL-6) levels are among the most robust predictors of these outcomes. Tocilizumab (TCZ) blocks the receptor for IL-6, inhibiting functions of this cytokine. METHODS: This was a 40-week, placebo-controlled, crossover trial (NCT02049437) where PWH on stable antiretroviral therapy (ART) were randomized to receive 3 monthly doses of TCZ or matching placebo intravenously. Following a 10-week treatment period and a 12-week washout, participants were switched to the opposite treatment. The primary endpoints were safety and posttreatment levels of C-reactive protein (CRP) and CD4+ T-cell cycling. Secondary endpoints included changes in inflammatory indices and lipid levels. RESULTS: There were 9 treatment-related toxicities of grade 2 or greater during TCZ administration (mostly neutropenia) and 2 during placebo administration. Thirty-one of 34 participants completed the study and were included in a modified intent-to-treat analysis. TCZ reduced levels of CRP (median decrease, 1819.9 ng/mL, P < .0001; effect size, 0.87) and reduced inflammatory markers in PWH, including D-dimer, soluble CD14, and tumor necrosis factor receptors. T-cell cycling tended to decrease in all maturation subsets after TCZ administration, but was only significant among naive CD4 T cells. Lipid levels, including lipid classes that have been related to cardiovascular disease risk, increased during TCZ treatment. CONCLUSIONS: TCZ is safe and decreases inflammation in PWH; IL-6 is a key driver of the inflammatory environment that predicts morbidity and mortality in ART-treated PWH. The clinical significance of lipid elevations during TCZ treatment requires further study. Clinical Trials Registration. NCT02049437.


Assuntos
Infecções por HIV , Interleucina-6 , Humanos , Infecções por HIV/tratamento farmacológico , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Lipídeos , Estudos Cross-Over
12.
Plast Reconstr Surg ; 152(5): 1087-1098, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36940145

RESUMO

BACKGROUND: Minimally invasive techniques for treatment-resistant migraine have been developed on recent insights into the peripheral pathogenesis of migraines. Although there is a growing body of evidence supporting these techniques, no study has yet compared the effects of these treatments on headache frequency, severity, duration, and cost. METHODS: PubMed, Embase, and Cochrane Library databases were searched to identify randomized placebo-controlled trials that compared radiofrequency ablation, botulinum toxin type A (BT-A), nerve block, neurostimulation, or migraine surgery to placebo for preventive treatment. Data on changes from baseline to follow-up in headache frequency, severity, duration, and quality of life were analyzed. RESULTS: A total of 30 randomized controlled trials and 2680 patients were included. Compared with placebo, there was a significant decrease in headache frequency in patients with nerve block ( P = 0.04) and surgery ( P < 0.001). Headache severity decreased in all treatments. Duration of headaches was significantly reduced in the BT-A ( P < 0.001) and surgery cohorts ( P = 0.01). Quality of life improved significantly in patients with BT-A, nerve stimulator, and migraine surgery. Migraine surgery had the longest lasting effects (11.5 months) compared with nerve ablation (6 months), BT-A (3.2 months), and nerve block (11.9 days). CONCLUSIONS: Migraine surgery is a cost-effective, long-term treatment to reduce headache frequency, severity, and duration without significant risk of complication. BT-A reduces headache severity and duration, but it is short-lasting and associated with greater adverse events and lifetime cost. Although efficacious, radiofrequency ablation and implanted nerve stimulators have high risks of adverse events and explantation, whereas benefits of nerve blocks are short in duration.


Assuntos
Toxinas Botulínicas Tipo A , Transtornos de Enxaqueca , Bloqueio Nervoso , Humanos , Qualidade de Vida , Transtornos de Enxaqueca/cirurgia , Transtornos de Enxaqueca/tratamento farmacológico , Toxinas Botulínicas Tipo A/uso terapêutico , Cefaleia , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Biostatistics ; 24(4): 885-900, 2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-35403204

RESUMO

A Bayesian framework for group testing under dilution effects has been developed, using lattice-based models. This work has particular relevance given the pressing public health need to enhance testing capacity for coronavirus disease 2019 and future pandemics, and the need for wide-scale and repeated testing for surveillance under constantly varying conditions. The proposed Bayesian approach allows for dilution effects in group testing and for general test response distributions beyond just binary outcomes. It is shown that even under strong dilution effects, an intuitive group testing selection rule that relies on the model order structure, referred to as the Bayesian halving algorithm, has attractive optimal convergence properties. Analogous look-ahead rules that can reduce the number of stages in classification by selecting several pooled tests at a time are proposed and evaluated as well. Group testing is demonstrated to provide great savings over individual testing in the number of tests needed, even for moderately high prevalence levels. However, there is a trade-off with higher number of testing stages, and increased variability. A web-based calculator is introduced to assist in weighing these factors and to guide decisions on when and how to pool under various conditions. High-performance distributed computing methods have also been implemented for considering larger pool sizes, when savings from group testing can be even more dramatic.


Assuntos
COVID-19 , Vigilância em Saúde Pública , Humanos , Algoritmos , Teorema de Bayes , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Pandemias
14.
Alzheimers Res Ther ; 14(1): 198, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36581878

RESUMO

BACKGROUND: Efavirenz is an anti-HIV drug, and cytochrome P450 46A1 (CYP46A1) is a CNS-specific enzyme that metabolizes cholesterol to 24-hydroxycholesterol (24HC). We have previously shown that allosteric CYP46A1 activation by low-dose efavirenz in a transgenic mouse model of Alzheimer's disease (AD) enhanced both cholesterol elimination and turnover in the brain and improved animal performance in memory tests. Here, we sought to determine whether CYP46A1 could be similarly activated by a low-dose efavirenz in human subjects.  METHODS: This pilot study enrolled 5 subjects with early AD. Participants were randomized to placebo (n = 1) or two daily efavirenz doses (50 mg and 200 mg, n = 2 for each) for 20 weeks and evaluated for safety and CYP46A1 target engagement (plasma 24HC levels). A longitudinal mixed model was used to ascertain the statistical significance of target engagement. We also measured 24HC in CSF and conducted a unique stable isotope labeling kinetics (SILK) study with deuterated water to directly measure CYP46A1 activity changes in the brain. RESULTS: In subjects receiving efavirenz, there was a statistically significant within-group increase (P ≤ 0.001) in the levels of plasma 24HC from baseline. The levels of 24HC in the CSF of subjects on the 200-mg dose of efavirenz were also increased. Target engagement was further supported by the labeling kinetics of 24HC by deuterated water in the SILK study. There were no serious adverse effects in any subjects. CONCLUSIONS: Our findings suggest efavirenz target engagement in human subjects with early AD. This supports the pursuit of a larger trial for further determination and confirmation of the efavirenz dose that exerts maximal enzyme activation, as well as evaluation of this drug's effects on AD biomarkers and clinical symptomatology. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03706885.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Colesterol , Colesterol 24-Hidroxilase/metabolismo , Colesterol 24-Hidroxilase/uso terapêutico , Projetos Piloto
15.
J Neural Eng ; 19(5)2022 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-36174538

RESUMO

Objective.Vagus nerve stimulation (VNS) is Food and Drug Administration-approved for epilepsy, depression, and obesity, and stroke rehabilitation; however, the morphological anatomy of the vagus nerve targeted by stimulatation is poorly understood. Here, we used microCT to quantify the fascicular structure and neuroanatomy of human cervical vagus nerves (cVNs).Approach.We collected eight mid-cVN specimens from five fixed cadavers (three left nerves, five right nerves). Analysis focused on the 'surgical window': 5 cm of length, centered around the VNS implant location. Tissue was stained with osmium tetroxide, embedded in paraffin, and imaged on a microCT scanner. We visualized and quantified the merging and splitting of fascicles, and report a morphometric analysis of fascicles: count, diameter, and area.Main results.In our sample of human cVNs, a fascicle split or merge event was observed every ∼560µm (17.8 ± 6.1 events cm-1). Mean morphological outcomes included: fascicle count (6.6 ± 2.8 fascicles; range 1-15), fascicle diameter (514 ± 142µm; range 147-1360µm), and total cross-sectional fascicular area (1.32 ± 0.41 mm2; range 0.58-2.27 mm).Significance.The high degree of fascicular splitting and merging, along with wide range in key fascicular morphological parameters across humans may help to explain the clinical heterogeneity in patient responses to VNS. These data will enable modeling and experimental efforts to determine the clinical effect size of such variation. These data will also enable efforts to design improved VNS electrodes.


Assuntos
Epilepsia , Estimulação do Nervo Vago , Humanos , Estudos Transversais , Nervo Vago/fisiologia , Estimulação do Nervo Vago/métodos , Cadáver
16.
J Perinatol ; 42(11): 1480-1484, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35927485

RESUMO

OBJECTIVES: To determine the association between human milk exposure at 3 months corrected gestational age and recurrent wheeze in preterm Black infants. METHODS: This is a secondary analysis of data from the D-Wheeze trial (ClinicalTrials.gov identifier NCT01601847). Associations between human milk feeding at 3 months corrected age and wheezing outcomes were examined by generalized linear models. RESULTS: Exclusively human milk fed infants (n = 13) had significantly fewer wheezing episodes than formula fed infants (n = 230) (IRR (95% CI) = 0.25 (0.07, 0.89), p = 0.03). There were no hospitalizations in infants receiving exclusive human milk. Receiving any human milk was associated with decreased odds of hospitalization by 12 months corrected age (OR (95% CI) = 0.12 (0.02, 0.79), p = 0.03). CONCLUSIONS: Exclusive human milk feeding at three months corrected gestational age is associated with decreased number of wheezing episodes in the first year of life in preterm Black infants.


Assuntos
Leite Humano , Sons Respiratórios , Feminino , Humanos , Lactente , Recém-Nascido , População Negra , Aleitamento Materno , Hospitalização , Fórmulas Infantis , Recém-Nascido Prematuro
17.
J Gen Intern Med ; 37(15): 3797-3804, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35945470

RESUMO

BACKGROUND: Communication of the benefits and harms of blood pressure lowering strategy is crucial for shared decision-making. OBJECTIVES: To quantify the effect of intensive versus standard systolic blood pressure lowering in terms of the number of event-free days DESIGN: Post hoc analysis of the Systolic Blood Pressure Intervention Trial PARTICIPANTS: A total of 9361 adults 50 years or older without diabetes or stroke who had a systolic blood pressure of 130-180 mmHg and elevated cardiovascular risk INTERVENTIONS: Intensive (systolic blood pressure goal <120 mmHg) versus standard blood pressure lowering (<140 mmHg) MAIN MEASURES: Days free of major adverse cardiovascular events (MACE), serious adverse events (SAE), and monitored adverse events (hypotension, syncope, bradycardia, electrolyte abnormalities, injurious falls, or acute kidney injury) over a median follow-up of 3.33 years KEY RESULTS: The intensive treatment group gained 14.7 more MACE-free days over 4 years (difference, 14.7 [95% confidence interval: 5.1, 24.4] days) than the standard treatment group. The benefit of the intensive treatment varied by cognitive function (normal: difference, 40.7 [13.0, 68.4] days; moderate-to-severe impairment: difference, -15.0 [-56.5, 26.4] days; p-for-interaction=0.009) and self-rated health (excellent: difference, -22.7 [-51.5, 6.1] days; poor: difference, 156.1 [31.1, 281.2] days; p-for-interaction=0.001). The mean overall SAE-free days were not significantly different between the treatments (difference, -14.8 [-35.3, 5.7] days). However, the intensive treatment group had 28.5 fewer monitored adverse event-free days than the standard treatment group (difference, -28.5 [-40.3, -16.7] days), with significant variations by frailty status (non-frail: difference, 38.8 [8.4, 69.2] days; frail: difference, -15.5 [-46.6, 15.7] days) and self-rated health (excellent: difference, -12.9 [-45.5, 19.7] days; poor: difference, 180.6 [72.9, 288.4] days; p-for-interaction <0.001). CONCLUSIONS: Over 4 years, intensive systolic blood pressure lowering provides, on average, 14.7 more MACE-free days than standard treatment, without any difference in SAE-free days. Whether this time-based effect summary improves shared decision-making remains to be elucidated. TRIAL REGISTRATION: ClinicalTrials.gov Registration: NCT01206062.


Assuntos
Injúria Renal Aguda , Doenças Cardiovasculares , Hipertensão , Acidente Vascular Cerebral , Adulto , Humanos , Pressão Sanguínea/fisiologia , Anti-Hipertensivos/efeitos adversos , Hipertensão/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Doenças Cardiovasculares/tratamento farmacológico
18.
Brain Sci ; 12(6)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35741586

RESUMO

Gait deficits are often persistent after stroke, and current rehabilitation methods do not restore normal gait for everyone. Targeted methods of focused gait therapy that meet the individual needs of each stroke survivor are needed. Our objective was to develop and test a combination protocol of simultaneous brain stimulation and focused stance phase training for people with chronic stroke (>6 months). We combined Transcranial Direct Current Stimulation (tDCS) with targeted stance phase therapy using Virtual Reality (VR)-assisted treadmill training and overground practice. The training was guided by motor learning principles. Five users (>6 months post-stroke with stance phase gait deficits) completed 10 treatment sessions. Each session began with 30 min of VR-assisted treadmill training designed to apply motor learning (ML)-based stance phase targeted practice. During the first 15 min of the treadmill training, bihemispheric tDCS was simultaneously delivered. Immediately after, users completed 30 min of overground (ML)-based gait training. The outcomes included the feasibility of protocol administration, gait speed, Timed Up and Go (TUG), Functional Gait Assessment (FGA), paretic limb stance phase control capability, and the Fugl−Meyer for lower extremity coordination (FMLE). The changes in the outcome measures (except the assessments of stance phase control capability) were calculated as the difference from baseline. Statistically and clinically significant improvements were observed after 10 treatment sessions in gait speed (0.25 ± 0.11 m/s) and FGA (4.55 ± 3.08 points). Statistically significant improvements were observed in TUG (2.36 ± 3.81 s) and FMLE (4.08 ± 1.82 points). A 10-session intervention combining tDCS and ML-based task-specific gait rehabilitation was feasible and produced clinically meaningful improvements in lower limb function in people with chronic gait deficits after stroke. Because only five users tested the new protocol, the results cannot be generalized to the whole population. As a contribution to the field, we developed and tested a protocol combining brain stimulation and ML-based stance phase training for individuals with chronic stance phase deficits after stroke. The protocol was feasible to administer; statistically and/or clinically significant improvements in gait function across an array of gait performance measures were observed with this relatively short treatment protocol.

19.
Nat Cancer ; 3(7): 852-865, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35681100

RESUMO

Nutrient-deprived conditions in the tumor microenvironment (TME) restrain cancer cell viability due to increased free radicals and reduced energy production. In pancreatic cancer cells a cytosolic metabolic enzyme, wild-type isocitrate dehydrogenase 1 (wtIDH1), enables adaptation to these conditions. Under nutrient starvation, wtIDH1 oxidizes isocitrate to generate α-ketoglutarate (αKG) for anaplerosis and NADPH to support antioxidant defense. In this study, we show that allosteric inhibitors of mutant IDH1 (mIDH1) are potent wtIDH1 inhibitors under conditions present in the TME. We demonstrate that low magnesium levels facilitate allosteric inhibition of wtIDH1, which is lethal to cancer cells when nutrients are limited. Furthermore, the Food & Drug Administration (FDA)-approved mIDH1 inhibitor ivosidenib (AG-120) dramatically inhibited tumor growth in preclinical models of pancreatic cancer, highlighting this approach as a potential therapeutic strategy against wild-type IDH1 cancers.


Assuntos
Isocitrato Desidrogenase , Neoplasias Pancreáticas , Regulação Alostérica , Inibidores Enzimáticos/farmacologia , Humanos , Isocitrato Desidrogenase/genética , Mutação , Nutrientes , Neoplasias Pancreáticas/tratamento farmacológico , Microambiente Tumoral , Neoplasias Pancreáticas
20.
Int J Med Educ ; 13: 107-114, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35506483

RESUMO

Objectives: To evaluate student impressions of learning anatomy with mixed-reality and compare long-term information retention of female breast anatomy between students who learned with a mixed-reality supplement and their classmates who dissected cadavers. Methods: In Part 1, 38 first-year medical student volunteers, randomly divided into two groups, completed a mixed-reality module and cadaveric dissection on the female breast in a counterbalanced design. Participants also completed post-quizzes and surveys. Part 2 was a non-randomized controlled trial, 8-months after completing Part 1 and 6-months after a final exam on this content. The performance of twenty-two Part 1 participants and 129 of their classmates, who only dissected, was compared on a delayed post-quiz. Wilcoxon signed-rank test, Mann-Whitney U test, and 95% confidence intervals were used to analyze the data. Results: In Part 1, the Wilcoxon signed-rank test determined that participants expressed significantly more positive responses to mixed-reality and found mixed-reality easier for learning and teamwork. In Part 2, the Mann-Whitney U test found mixed-reality participants scored significantly higher on a delayed-post quiz than their classmates who only dissected (U = 928, p < .009). Conclusions:   This study suggests that medical students may prefer mixed-reality and that it may be an effective modality for learning breast anatomy while facilitating teamwork. Results also suggest that supplementing cadaveric dissection with mixed-reality may improve long-term retention for at least one anatomical topic. It is recommended that similar studies evaluate a larger sample and additional anatomical regions to determine the generalizability of these findings.


Assuntos
Estudantes de Medicina , Cadáver , Currículo , Avaliação Educacional/métodos , Feminino , Humanos , Aprendizagem
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