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1.
Curr Opin Neurol ; 37(5): 467-477, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864534

RESUMO

PURPOSE OF REVIEW: To examine the evidence evaluating the association between obesity and neuropathy as well as potential interventions. RECENT FINDINGS: Although diabetes has long been associated with neuropathy, additional metabolic syndrome components, including obesity, are increasingly linked to neuropathy development, regardless of glycemic status. Preclinical rodent models as well as clinical studies are shedding light on the mechanisms of obesity-related neuropathy as well as challenges associated with slowing progression. Dietary and surgical weight loss and exercise interventions are promising, but more data is needed. SUMMARY: High-fat-diet rodent models have shown that obesity-related neuropathy is a product of excess glucose and lipid accumulation leading to inflammation and cell death. Clinical studies consistently demonstrate obesity is independently associated with neuropathy; therefore, likely a causal risk factor. Dietary weight loss improves neuropathy symptoms but not examination scores. Bariatric surgery and exercise are promising interventions, but larger, more rigorous studies are needed. Further research is also needed to determine the utility of weight loss medications and ideal timing for obesity interventions to prevent neuropathy.


Assuntos
Obesidade , Humanos , Obesidade/epidemiologia , Obesidade/complicações , Animais , Doenças do Sistema Nervoso Periférico/epidemiologia , Doenças do Sistema Nervoso Periférico/etiologia , Doenças do Sistema Nervoso Periférico/terapia , Redução de Peso/fisiologia , Cirurgia Bariátrica
2.
Muscle Nerve ; 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39072773

RESUMO

INTRODUCTION/AIMS: Given the importance of early diagnosis and treatment of myasthenia gravis (MG), it is critical to understand disparities in MG care. We aimed to determine if there are any differences in testing, treatment, and/or access to neurologists for patients of varying sex and race/ethnicity with MG. METHODS: We used a nationally representative healthcare claims database of privately insured individuals (2001-2018) to identify incident cases of MG using a validated definition. Diagnostic testing, steroid-sparing agents, intravenous immunoglobulin (IVIG), plasma exchange (PLEX), and thymectomy were defined using drug names or CPT codes. Steroid use was defined using AHFS class codes. We also determined whether an individual had a visit to a neurologist and the time between primary care and neurologist visits. Logistic regression determined associations between sex and race/ethnicity and testing, treatments, and access to neurologists. RESULTS: Female patients were less likely to get a computed tomography (CT) chest (odds ratio (OR) 0.73, 95% confidence interval (CI): 0.64-0.83), receive steroids (OR: 0.85, 95% CI: 0.75-0.97), steroid-sparing agents (OR: 0.84, 95% CI: 0.72-0.97), and IVIG or PLEX (OR: 0.80, 95% CI: 0.67-0.95). Black patients were less likely to receive steroids (OR: 0.78, 95% CI: 0.63-0.96). No significant disparities were seen in access to neurologists. DISCUSSION: We found healthcare disparities in MG treatment with female and Black patients receiving less treatment than men and those of other races/ethnicities. Further research and detailed assessments accounting for individual patient factors are needed to confirm these apparent disparities.

3.
Diabetologia ; 66(7): 1192-1207, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36917280

RESUMO

AIMS/HYPOTHESIS: The aim of this study was to determine the effect of bariatric surgery on diabetes complications in individuals with class II/III obesity (BMI > 35 kg/m2). METHODS: We performed a prospective cohort study of participants with obesity who underwent bariatric surgery. At baseline and 2 years following surgery, participants underwent metabolic phenotyping and diabetes complication assessments. The primary outcomes for peripheral neuropathy (PN) were a change in intra-epidermal nerve fibre density (IENFD, units = fibres/mm) at the distal leg and proximal thigh, the primary outcome for cardiovascular autonomic neuropathy (CAN) was a change in the expiration/inspiration (E/I) ratio, and the primary outcome for retinopathy was a change in the mean deviation on frequency doubling technology testing. RESULTS: Among 127 baseline participants, 79 completed in-person follow-up (age 46.0 ± 11.3 years [mean ± SD], 73.4% female). Participants lost a mean of 31.0 kg (SD 18.4), and all metabolic risk factors improved except for BP and total cholesterol. Following bariatric surgery, one of the primary PN outcomes improved (IENFD proximal thigh, +3.4 ± 7.8, p<0.01), and CAN (E/I ratio -0.01 ± 0.1, p=0.89) and retinopathy (deviation -0.2 ± 3.0, p=0.52) were stable. Linear regression revealed that a greater reduction in fasting glucose was associated with improvements in retinopathy (mean deviation point estimate -0.7, 95% CI -1.3, -0.1). CONCLUSIONS/INTERPRETATION: Bariatric surgery may be an effective approach to reverse PN in individuals with obesity. The observed stability of CAN and retinopathy may be an improvement compared with the natural progression of these conditions; however, controlled trials are needed.


Assuntos
Cirurgia Bariátrica , Complicações do Diabetes , Diabetes Mellitus Tipo 2 , Obesidade Mórbida , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Estudos Prospectivos , Obesidade/complicações , Obesidade/cirurgia , Cirurgia Bariátrica/efeitos adversos , Redução de Peso , Complicações do Diabetes/complicações , Obesidade Mórbida/cirurgia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/cirurgia
4.
Muscle Nerve ; 67(1): 45-51, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36367146

RESUMO

INTRODUCTION/AIMS: In vasculitic neuropathy (VN), a 50% side-to-side difference in the amplitude of compound muscle action potentials and sensory nerve action potentials is considered meaningful, but unequivocal evidence is lacking. The aim of this study is to characterize electrodiagnostic features that best distinguish VN from other axonal polyneuropathies. METHODS: We conducted a case-control study between January 2000 and April 2021. We reviewed the records of patients with VN who had bilateral nerve conduction studies (NCS) and evaluated different electrodiagnostic models to help distinguish VN from non-inflammatory axonal polyneuropathies. RESULTS: We identified 82 cases, and 174 controls with non-inflammatory axonal neuropathies. The amplitude percent difference Z-score model showed the best discriminatory capability between cases and controls (area under the curve [AUC] 0.87; 95% confidence interval [CI] 0.82, 0.93), and the number of nerves tested did not significantly influence the model. Individually, the ulnar motor nerve (AUC 0.86; 95% CI 0.77, 0.94) and median motor nerve (AUC 0.85; 95% CI 0.77, 0.94) showed the best discriminatory capability. A 50% amplitude difference between at least two bilateral nerves, either in the upper (AUC 0.85; 95% CI 0.77, 0.93) or lower (AUC 0.79; 95% CI 0.71, 0.87) extremity showed good discriminatory threshold for detecting VN. DISCUSSION: The best electrodiagnostic criteria for VN utilizes z-scores of percent differences in nerve amplitudes, but this approach may be difficult to implement at the bedside. Alternately, a 50% amplitude difference in at least two nerves is a reasonable approximation.


Assuntos
Doenças do Sistema Nervoso Periférico , Polineuropatias , Humanos , Condução Nervosa/fisiologia , Estudos de Condução Nervosa , Estudos de Casos e Controles , Doenças do Sistema Nervoso Periférico/diagnóstico , Polineuropatias/diagnóstico
5.
Headache ; 62(1): 36-56, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35041218

RESUMO

OBJECTIVE: The objective of this study was to understand current practice, clinician understanding, attitudes, barriers, and facilitators to optimal headache neuroimaging practices. BACKGROUND: Headaches are common in adults, and neuroimaging for these patients is common, costly, and increasing. Although guidelines recommend against routine headache neuroimaging in low-risk scenarios, guideline-discordant neuroimaging is still frequently performed. METHODS: We administered a 60-item survey to headache clinicians at the Veterans Affairs health system to assess clinician understanding and attitudes on headache neuroimaging and to determine neuroimaging practice patterns for three scenarios describing hypothetical patients with headaches. Descriptive statistics were used to summarize responses, stratified by clinician type (physicians or advanced practice clinicians [APCs]) and specialty (neurology or primary care). RESULTS: The survey was successfully completed by 431 of 1426 clinicians (30.2% response rate). Overall, 317 of 429 (73.9%) believed neuroimaging was overused for patients with headaches. However, clinicians would utilize neuroimaging a mean (SD) 30.9% (31.7) of the time in a low-risk scenario without red flags, and a mean 67.1% (31.9) of the time in the presence of minor red flags. Clinicians had stronger beliefs in the potential benefits (268/429, 62.5%) of neuroimaging compared to harms (181/429, 42.2%) and more clinicians were bothered by harms stemming from the omission of neuroimaging (377/426, 88.5%) compared to commission (329/424, 77.6%). Additionally, APCs utilized neuroimaging more frequently than physicians and were more receptive to potential interventions to improve neuroimaging utilization. CONCLUSIONS: Although a majority of clinicians believed neuroimaging was overused for patients with headaches, many would utilize neuroimaging in low-risk scenarios with a small probability of changing management. Future studies are needed to define the role of currently used red flags given their importance in neuroimaging decisions. Importantly, APCs may be an ideal target for future optimization efforts.


Assuntos
Atitude do Pessoal de Saúde , Utilização de Instalações e Serviços , Transtornos da Cefaleia/diagnóstico por imagem , Cefaleia/diagnóstico por imagem , Imageamento por Ressonância Magnética , Neuroimagem , Pesquisas sobre Atenção à Saúde , Humanos , Profissionais de Enfermagem , Assistentes Médicos , Médicos , Estados Unidos , United States Department of Veterans Affairs
6.
Oral Dis ; 28(1): 193-201, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33274559

RESUMO

BACKGROUND: A case-control study was performed to define clinical and genetic risk factors associated with osteonecrosis of the jaw in patients with metastatic cancer treated with bisphosphonates. METHODS: Clinical data and tissues were collected from patients treated with bisphosphonates for metastatic bone disease who were diagnosed with osteonecrosis of the jaw (cases) and matched controls. Clinical data included patient, behavioral, disease, and treatment information. Genetic polymorphisms in CYP2C8 (rs1934951) and other candidate genes were genotyped. Odds ratios from conditional logistic regression models were examined to identify clinical and genetic characteristics associated with case or control status. RESULTS: The study population consisted of 76 cases and 126 controls. In the final multivariable clinical model, patients with osteonecrosis of the jaw were less likely to have received pamidronate than zoledronic acid (odds ratio = 0.18, 95% Confidence interval: 0.03-0.97, p = .047) and more likely to have been exposed to bevacizumab (OR = 5.15, 95% CI: 1.67-15.95, p = .005). The exploratory genetic analyses suggested a protective effect for VEGFC rs2333496 and risk effects for VEGFC rs7664413 and PPARG rs1152003. CONCLUSIONS: We observed patients with ONJ were more likely to have been exposed to bevacizumab and zoledronic and identified potential genetic predictors that require validation prior to clinical translation.


Assuntos
Conservadores da Densidade Óssea , Neoplasias , Osteonecrose , Conservadores da Densidade Óssea/efeitos adversos , Estudos de Casos e Controles , Difosfonatos/efeitos adversos , Humanos , Fatores de Risco
7.
Cardiol Young ; 32(10): 1649-1656, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34924086

RESUMO

BACKGROUND: Cardiac intensivists frequently assess patient readiness to wean off mechanical ventilation with an extubation readiness trial despite it being no more effective than clinician judgement alone. We evaluated the utility of high-frequency physiologic data and machine learning for improving the prediction of extubation failure in children with cardiovascular disease. METHODS: This was a retrospective analysis of clinical registry data and streamed physiologic extubation readiness trial data from one paediatric cardiac ICU (12/2016-3/2018). We analysed patients' final extubation readiness trial. Machine learning methods (classification and regression tree, Boosting, Random Forest) were performed using clinical/demographic data, physiologic data, and both datasets. Extubation failure was defined as reintubation within 48 hrs. Classifier performance was assessed on prediction accuracy and area under the receiver operating characteristic curve. RESULTS: Of 178 episodes, 11.2% (N = 20) failed extubation. Using clinical/demographic data, our machine learning methods identified variables such as age, weight, height, and ventilation duration as being important in predicting extubation failure. Best classifier performance with this data was Boosting (prediction accuracy: 0.88; area under the receiver operating characteristic curve: 0.74). Using physiologic data, our machine learning methods found oxygen saturation extremes and descriptors of dynamic compliance, central venous pressure, and heart/respiratory rate to be of importance. The best classifier in this setting was Random Forest (prediction accuracy: 0.89; area under the receiver operating characteristic curve: 0.75). Combining both datasets produced classifiers highlighting the importance of physiologic variables in determining extubation failure, though predictive performance was not improved. CONCLUSION: Physiologic variables not routinely scrutinised during extubation readiness trials were identified as potential extubation failure predictors. Larger analyses are necessary to investigate whether these markers can improve clinical decision-making.


Assuntos
Extubação , Desmame do Respirador , Humanos , Criança , Desmame do Respirador/métodos , Estudos Retrospectivos , Unidades de Terapia Intensiva Pediátrica , Aprendizado de Máquina
8.
Chembiochem ; 21(21): 3146-3150, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32529779

RESUMO

A pair of 9-mesityl-10-phenyl acridinium (Mes-Acr+ ) photoredox catalysts were synthesized with an iodoacetamide handle for cysteine bioconjugation. Covalently tethering of the synthetic Mes-Acr+ cofactors with a small panel of thermostable protein scaffolds resulted in 12 new artificial enzymes. The unique chemical and structural environment of the protein hosts had a measurable effect on the photophysical properties and photocatalytic activity of the cofactors. The constructed Mes-Acr+ hybrid enzymes were found to be active photoinduced electron-transfer catalysts, controllably oxidizing a variety of aryl sulfides when irradiated with visible light, and possessed activities that correlated with the photophysical characterization data. Their catalytic performance was found to depend on multiple factors including the Mes-Acr+ cofactor, the protein scaffold, the location of cofactor immobilization, and the substrate. This work provides a framework toward adapting synthetic photoredox catalysts into artificial cofactors and includes important considerations for future bioengineering efforts.


Assuntos
Acridinas/síntese química , Acridinas/metabolismo , Cisteína/metabolismo , Desenho de Fármacos , Iodoacetamida/metabolismo , Oxigenases/metabolismo , Acridinas/química , Catálise , Cisteína/química , Transporte de Elétrons , Iodoacetamida/química , Modelos Moleculares , Estrutura Molecular , Oxirredução , Oxigenases/química , Processos Fotoquímicos
9.
Muscle Nerve ; 61(5): 640-644, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31811650

RESUMO

INTRODUCTION: Despite the existence of guidelines, painful neuropathy is often inappropriately treated. We sought to determine the effectiveness of a clinical decision support system on guideline-recommended medication use. METHODS: We randomized neurology providers, stratified by subspecialty, to a best practice alert (BPA) linked to a Smartset or a BPA alone when seeing patients with neuropathy. The primary outcome was the proportion of patients with uncontrolled nerve pain prescribed a guideline-recommended medication. Generalized estimating equations were used to assess effectiveness. RESULTS: Seventy-five neurology providers (intervention 38, control 37) treated 2697 patients with neuropathy (intervention 1026, control 671). Providers did not acknowledge the BPA in 1928 (71.5%) visits. Only four of eight intervention arm neurologists who treated patients with uncontrolled nerve pain opened the Smartset. The intervention was not associated with guideline-recommended medication use (odds ratio 0.52, 0.18-1.48; intervention 52%, control 54.8%). DISCUSSION: Our intervention did not improve prescribing practices for painful neuropathy. Physicians typically ignored the BPAs/Smartset; therefore, future studies should mandate their use or employ alternate strategies.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Sistemas de Apoio a Decisões Clínicas , Neuralgia/tratamento farmacológico , Polineuropatias/tratamento farmacológico , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Idoso , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Pessoa de Meia-Idade , Neurologistas , Profissionais de Enfermagem , Manejo da Dor , Padrões de Prática em Enfermagem
10.
Muscle Nerve ; 60(3): 305-307, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31228276

RESUMO

INTRODUCTION: Nerve conduction studies are used to aid in the diagnosis of distal symmetric polyneuropathy (DSP). It is unclear whether bilateral lower extremity nerve conduction studies (NCS) are needed when evaluating for suspected DSP. METHODS: We retrospectively analyzed NCS from patients who presented to the University of Michigan electromyography laboratory between July 1, 2016 and December 31, 2017 with symptoms of DSP to assess agreement and correlation between left and right lower extremity NCS parameters. RESULTS: We found significant agreement between abnormalities in individual nerve parameters of the left and right lower extremities of 105 patients, most notably in the sural nerve. In the 53 patients with bilateral sural, peroneal, and tibial studies, there was also significant agreement between whether the left and right met electrodiagnostic criteria for DSP (κ = 0.77). DISCUSSION: Bilateral lower extremity NCS may have limited utility in the evaluation of suspected DSP. Muscle Nerve, 2019.


Assuntos
Neuropatias Diabéticas/fisiopatologia , Condução Nervosa/fisiologia , Polineuropatias/fisiopatologia , Nervo Sural/fisiopatologia , Potenciais de Ação/fisiologia , Adulto , Idoso , Neuropatias Diabéticas/diagnóstico , Eletrodiagnóstico/métodos , Eletromiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polineuropatias/diagnóstico , Estudos Retrospectivos , Nervo Tibial/fisiopatologia
12.
Chembiochem ; 18(24): 2380-2384, 2017 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-29024391

RESUMO

A cytochrome P450 was engineered to selectively incorporate Ir(Me)-deuteroporphyrin IX (Ir(Me)-DPIX), in lieu of heme, in bacterial cells. Cofactor selectivity was altered by introducing mutations within the heme-binding pocket to discriminate the deuteroporphyrin macrocycle, in combination with mutations to the P450 axial cysteine to accommodate a pendant methyl group on the Ir(Me) center. This artificial metalloenzyme was investigated for activity in non-native metallocarbenoid-mediated olefin cyclopropanation reactions and showed enhanced activity for aliphatic and electron-deficient olefins when compared to the native heme enzyme. This work provides a general strategy to augment the chemical functionality of heme enzymes in cells with application towards abiotic catalysis.


Assuntos
Biocatálise , Metaloproteínas/síntese química , Engenharia de Proteínas , Bactérias/citologia , Sistema Enzimático do Citocromo P-450/química , Deutério , Heme/química , Irídio/química , Porfirinas/química
13.
Ann Surg Oncol ; 24(2): 340-346, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27495278

RESUMO

BACKGROUND: Lymph node ratio (LNR), positive nodes divided by nodes examined, has been proposed for prognostication in melanoma to mitigate problems with low node counts. However, it is unclear if LNR offers superior prognostication over total counts of positive nodes and nodes examined. Additionally, the prognostic value of LNR may change if a threshold number of nodes are examined. We evaluated whether LNR is more prognostic than positive nodes and nodes examined, and whether the prognostic value of LNR changes with minimum thresholds. METHODS: Using the National Cancer Data Base Participant User File, we identified 74,692 incident cases with nodal dissection during 2000-2006. We compared LNR versus counts of examined and positive nodes based on Harrell's C, a measure of predictive ability. We then stratified by total nodes examined: greater versus fewer than ten for axillary lymph node dissection (ALND) and greater versus fewer than five for inguinal lymph node dissection (ILND). RESULTS: Overall, LNR had a Harrell's C of 0.628 (95 % confidence interval [CI] 0.625-0.631). Examined and positive nodes were not significantly different from this, with a Harrell's C of 0.625 (95 % CI 0.621-0.630). In ALND, LNR had a Harrell's C of 0.626 (95 % CI 0.610-0.643) with ≥10 nodes versus 0.554 (95 % CI 0.551-0.558) < 10 nodes. In ILND, LNR had a Harrell's C of 0.679 (95 % CI 0.664-0.694) with ≥5 nodes versus C of 0.601 (95 % CI 0.595-0.606) < 5 nodes. CONCLUSIONS: LNR provides no prognostic superiority versus counts of examined and positive nodes. Moreover, the prognostic value of LNR diminishes when minimum node retrieval thresholds are not met.


Assuntos
Excisão de Linfonodo/mortalidade , Linfonodos/patologia , Melanoma/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Linfonodos/cirurgia , Masculino , Melanoma/mortalidade , Melanoma/patologia , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Taxa de Sobrevida
14.
J Am Chem Soc ; 138(38): 12451-8, 2016 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-27575374

RESUMO

We introduce a strategy that expands the functionality of hemoproteins through orthogonal enzyme/heme pairs. By exploiting the ability of a natural heme transport protein, ChuA, to promiscuously import heme derivatives, we have evolved a cytochrome P450 (P450BM3) that selectively incorporates a nonproteinogenic cofactor, iron deuteroporphyrin IX (Fe-DPIX), even in the presence of endogenous heme. Crystal structures show that selectivity gains are due to mutations that introduce steric clash with the heme vinyl groups while providing a complementary binding surface for the smaller Fe-DPIX cofactor. Furthermore, the evolved orthogonal enzyme/cofactor pair is active in non-natural carbenoid-mediated olefin cyclopropanation. This methodology for the generation of orthogonal enzyme/cofactor pairs promises to expand cofactor diversity in artificial metalloenzymes.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/metabolismo , Ferro/química , Metaloporfirinas/química , NADPH-Ferri-Hemoproteína Redutase/química , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Domínio Catalítico , Coenzimas , Evolução Molecular Direcionada , Metaloporfirinas/metabolismo , Modelos Moleculares , Estrutura Molecular , Mutação , Oxirredução
15.
Proc Natl Acad Sci U S A ; 109(31): 12746-51, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-22802636

RESUMO

Cyclic di-GMP (c-di-GMP) is a second messenger molecule that regulates the transition between sessile and motile lifestyles in bacteria. Bacteria often encode multiple diguanylate cyclase (DGC) and phosphodiesterase (PDE) enzymes that produce and degrade c-di-GMP, respectively. Because of multiple inputs into the c-di-GMP-signaling network, it is unclear whether this system functions via high or low specificity. High-specificity signaling is characterized by individual DGCs or PDEs that are specifically associated with downstream c-di-GMP-mediated responses. In contrast, low-specificity signaling is characterized by DGCs or PDEs that modulate a general signal pool, which, in turn, controls a global c-di-GMP-mediated response. To determine whether c-di-GMP functions via high or low specificity in Vibrio cholerae, we correlated the in vivo c-di-GMP concentration generated by seven DGCs, each expressed at eight different levels, to the c-di-GMP-mediated induction of biofilm formation and transcription. There was no correlation between total intracellular c-di-GMP levels and biofilm formation or gene expression when considering all states. However, individual DGCs showed a significant correlation between c-di-GMP production and c-di-GMP-mediated responses. Moreover, the rate of phenotypic change versus c-di-GMP concentration was significantly different between DGCs, suggesting that bacteria can optimize phenotypic output to c-di-GMP levels via expression or activation of specific DGCs. Our results conclusively demonstrate that c-di-GMP does not function via a simple, low-specificity signaling pathway in V. cholerae.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , GMP Cíclico/análogos & derivados , Proteínas de Escherichia coli/metabolismo , Fósforo-Oxigênio Liases/metabolismo , Sistemas do Segundo Mensageiro/fisiologia , Vibrio cholerae/fisiologia , Proteínas de Bactérias/genética , GMP Cíclico/genética , GMP Cíclico/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Fósforo-Oxigênio Liases/genética
16.
Diabetes Care ; 47(9): 1638-1646, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39008530

RESUMO

OBJECTIVE: To determine bidirectional associations between the timing of chronic diabetes complications (CDCs) and mental health disorders (MHDs) in individuals with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS: We used a nationally representative health care claims database to identify matched individuals with type 1 or 2 diabetes or without diabetes using a propensity score quasirandomization technique stratified by age (0-19, 20-39, 40-59, and ≥60 years). CDCs and MHDs were identified using ICD-9/10 codes. We fit Cox proportional hazards models with time-varying diagnoses of CDCs or MHDs to investigate their association with the hazard of developing MHDs or CDCs, respectively. RESULTS: From 2001 to 2018, a total of 553,552 individuals were included (44,735 with type 1 diabetes, 152,187 with type 2 diabetes, and 356,630 without diabetes). We found that having a CDC increased the hazard of developing an MHD (hazard ratio [HR] 1.9-2.9; P < 0.05, with higher HRs in older age strata), and having an MHD increased the hazard of developing a CDC (HR 1.4-2.5; P < 0.05, with the highest HR in age stratum 0-19 years). In those aged <60 years, individuals with type 1 diabetes were more likely to have CDCs, whereas individuals with type 2 diabetes were more likely to have MHDs. However, the relationship between CDCs and MHDs in either direction was not affected by diabetes type (P > 0.05 for interaction effects). CONCLUSIONS: We found a consistent bidirectional association between CDCs and MHDs across the life span, highlighting the important relationship between CDCs and MHDs. Prevention and treatment of either comorbidity may help reduce the risk of developing the other.


Assuntos
Complicações do Diabetes , Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Transtornos Mentais , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Adulto , Pessoa de Meia-Idade , Masculino , Feminino , Adolescente , Transtornos Mentais/epidemiologia , Criança , Adulto Jovem , Pré-Escolar , Lactente , Complicações do Diabetes/epidemiologia , Recém-Nascido , Idoso , Modelos de Riscos Proporcionais
17.
J Fluoresc ; 23(2): 237-41, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23108568

RESUMO

We compare the bimolecular quenching rate constant (k2) of luminescent tris(2,2'-bipyridine)ruthenium(II) by oxygen in water, ethylene glycol and glycerol as a function of temperature and viscosity to several theoretical models. The Smoluchowski equation with experimentally determined diffusion coefficients produced calculated values that were in the best agreement with experiment. For the less viscous solvent, water, this equation produced a value that was approximately an order of magnitude larger than the experimental value. With an increase in solvent viscosity, the Smoluchowski value approached the experimental value. Using the Smoluchowski equation with calculated diffusion coefficients based on the known radii of the reacting species produced deviations an order of magnitude larger in water and a factor of two or three lower in ethylene glycol and glycerol. If an assumption is made that the radii of both molecules are equal, we have the Stokes Einstein equation, and the only parameters become temperature and viscosity. Using this relationship, the calculated values for water are about a factor of two larger and with ethylene glycol and glycerol about a factor of 6 smaller than experimental data. These results show that bimolecular quenching is a more complex process affected by many parameters such as solvent cage effects in addition to viscosity and temperature.

18.
Neurology ; 100(9): e884-e898, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36450601

RESUMO

BACKGROUND AND OBJECTIVES: The objective of this study was to compare the utilization and costs (total and out-of-pocket) of new-to-market neurologic medications with existing guideline-supported neurologic medications over time. METHODS: We used a healthcare pharmaceutical claims database (from 2001 to 2019) to identify patients with both a diagnosis of 1 of 11 separate neurologic conditions and either a new-to-market medication or an existing guideline-supported medication for that condition. Neurologic conditions included orthostatic hypotension, spinal muscular atrophy, Duchenne disease, Parkinson disease, multiple sclerosis, amyotrophic lateral sclerosis, myasthenia gravis, Huntington disease, tardive dyskinesia, transthyretin amyloidosis, and migraine. New-to-market medications were defined as all neurologic medications approved by the US Food and Drug Administration (FDA) between 2014 and 2018. In each year, we determined the median out-of-pocket and standardized total costs for a 30-day supply of each medication. We also measured the proportion of patients receiving new-to-market medications compared with all medications specific for the relevant condition. RESULTS: We found that the utilization of most new-to-market medications was small (<20% in all but 1 condition), compared with existing, guideline-supported medications. The out-of-pocket and standardized total costs were substantially larger for new-to-market medications. The median (25th percentile, 75th percentile) out-of-pocket costs for a 30-day supply in 2019 were largest for edaravone ($712.8 [$59.8-$802.0]) and eculizumab ($91.1 [$3.0-$3,216.4]). For new-to-market medications, the distribution of out-of-pocket costs was highly variable and the trends over time were unpredictable compared with existing guideline-supported medications. DISCUSSION: Despite the increasing number of FDA-approved neurologic medications, utilization of newly approved medications in the privately insured population remains small. Given the high costs and similar efficacy for most of the new medications, limited utilization may be appropriate. However, for new medications with greater efficacy, future studies are needed to determine whether high costs are a barrier to utilization.


Assuntos
Depressores do Sistema Nervoso Central , Doenças do Sistema Nervoso , Doença de Parkinson , Humanos , Custos e Análise de Custo , Gastos em Saúde , Preparações Farmacêuticas , Estudos Retrospectivos , Custos de Cuidados de Saúde
19.
Diabetes Res Clin Pract ; 205: 110983, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37890702

RESUMO

AIMS: Describe and compare healthcare costs and utilization for insured persons with type 1 diabetes (T1D), type 2 diabetes (T2D), and without diabetes in the United States. METHODS: Using a nationally representative healthcare claims database, we identified matched persons with T1D, T2D, and without diabetes using a propensity score quasi-randomization technique. In each year between 2009 and 2018, we report costs (total and out-of-pocket) and utilization for all healthcare services and those specific to medications, diabetes-related supplies, visits to providers, hospitalizations, and emergency department visits. RESULTS: In 2018, we found out-of-pocket costs and total costs were highest for persons with T1D (out-of-pocket: $2,037.2, total: $25,652.0), followed by T2D (out-of-pocket: $1,543.3, total: $22,408.1), and without diabetes (out-of-pocket: $1,122.7, total: $14,220.6). From 2009 to 2018, out-of-pocket costs were increasing for persons with T1D(+6.5 %) but decreasing for T2D (-7.5 %) and without diabetes (-2.3 %). Medication costs made up the largest proportion of out-of-pocket costs regardless of diabetes status (T1D: 51.4 %, T2D: 55.4 %,without diabetes: 51.1 %). CONCLUSIONS: Given the substantial out-of-pocket costs for people with diabetes, especially for those with T1D, providers should screen all persons with diabetes for financial toxicity (i.e., wide-ranging problems stemming from healthcare costs). In addition, policies that aim to lower out-of-pocket costs of cost-effective diabetes related healthcare are needed with a particular focus on medications.


Assuntos
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Humanos , Estados Unidos/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 1/terapia , Custos de Cuidados de Saúde , Serviços de Saúde , Custos de Medicamentos , Estudos Retrospectivos
20.
Ann Clin Transl Neurol ; 10(10): 1891-1898, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37518982

RESUMO

We performed a cross-sectional study to determine associations between cognition and MRI-derived brain outcomes, with obesity, diabetes duration, and metabolic risk factors in 51 Pima American Indians with longstanding type 2 diabetes (T2d) (mean [SD] age: 48.4 [11.3] years, T2d duration: 20.1 [9.1] years). Participants had similar cognition (NIH Toolbox Cognition Battery composite: 45.3 [9.8], p = 0.64, n = 51) compared to normative data. T2d duration, but not other metabolic risk factors, associated with decreased cortical thickness (Point Estimate (PE): -0.0061, 95%CI: -0.0113, -0.0009, n = 45), gray matter volume (PE: -830.39, 95%CI: -1503.14, -157.64, n = 45), and increased white matter hyperintensity volume (PE: 0.0389, 95%CI: 0.0049, 0.0729, n = 45).


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Estados Unidos , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/complicações , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Estudos Transversais , Fatores de Risco , Avaliação de Resultados em Cuidados de Saúde
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