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1.
Proc Natl Acad Sci U S A ; 118(2)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33402532

RESUMO

Pathogenic germline mutations in PIGV lead to glycosylphosphatidylinositol biosynthesis deficiency (GPIBD). Individuals with pathogenic biallelic mutations in genes of the glycosylphosphatidylinositol (GPI)-anchor pathway exhibit cognitive impairments, motor delay, and often epilepsy. Thus far, the pathophysiology underlying the disease remains unclear, and suitable rodent models that mirror all symptoms observed in human patients have not been available. Therefore, we used CRISPR-Cas9 to introduce the most prevalent hypomorphic missense mutation in European patients, Pigv:c.1022C > A (p.A341E), at a site that is conserved in mice. Mirroring the human pathology, mutant Pigv341E mice exhibited deficits in motor coordination, cognitive impairments, and alterations in sociability and sleep patterns, as well as increased seizure susceptibility. Furthermore, immunohistochemistry revealed reduced synaptophysin immunoreactivity in Pigv341E mice, and electrophysiology recordings showed decreased hippocampal synaptic transmission that could underlie impaired memory formation. In single-cell RNA sequencing, Pigv341E-hippocampal cells exhibited changes in gene expression, most prominently in a subtype of microglia and subicular neurons. A significant reduction in Abl1 transcript levels in several cell clusters suggested a link to the signaling pathway of GPI-anchored ephrins. We also observed elevated levels of Hdc transcripts, which might affect histamine metabolism with consequences for circadian rhythm. This mouse model will not only open the doors to further investigation into the pathophysiology of GPIBD, but will also deepen our understanding of the role of GPI-anchor-related pathways in brain development.


Assuntos
Glicosilfosfatidilinositóis/genética , Glicosilfosfatidilinositóis/metabolismo , Manosiltransferases/metabolismo , Anormalidades Múltiplas/genética , Sequência de Aminoácidos , Aminoácidos/genética , Animais , Sistemas CRISPR-Cas , Modelos Animais de Doenças , Epilepsia/genética , Glicosilfosfatidilinositóis/deficiência , Hipocampo/metabolismo , Deficiência Intelectual/genética , Manosiltransferases/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Mutação de Sentido Incorreto , Fenótipo , Engenharia de Proteínas/métodos , Convulsões/genética , Convulsões/fisiopatologia
2.
J Clin Psychol Med Settings ; 31(2): 471-492, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38265697

RESUMO

Family navigation (FN) and phone-based care coordination may improve linkages from primary care to community-based mental health referrals, but research on their differential impact is limited. This mixed-methods study compared FN and phone-based care coordination in connecting families to mental health services from primary care. Families of children (56.3% male, mean age = 10.4 years, 85.4% Black) were sequentially assigned to either receive FN through a family-run organization or phone-based coordination via the child psychiatry access program (CPAP). Caregiver-reported children's mental health improved in both groups and both groups were satisfied with services. More families in the CPAP group had appointments made or completed (87%) than families in the FN group (71%) though the difference was not statistically significant. Future research with a larger sample that matches family needs and preferences (e.g., level and type of support) with navigation services would be beneficial.


Assuntos
Atenção Primária à Saúde , Humanos , Masculino , Feminino , Criança , Serviços Comunitários de Saúde Mental/métodos , Encaminhamento e Consulta/estatística & dados numéricos , Família/psicologia , Navegação de Pacientes , Telefone , Adolescente , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos
3.
Brain Behav Immun ; 91: 181-193, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002631

RESUMO

While the original protein Toll in Drosophila melanogaster regulates both host defense and morphogenesis, the role of its ortholog Toll-like receptors (TLRs), the interleukin 1 receptor (IL-1R) family, and the associated signaling pathways in mammalian brain development and structure is poorly understood. Because the adaptor protein myeloid differentiation primary response protein 88 (MyD88) is essential for downstream signaling of most TLRs and IL-1R, we systematically investigated the effect of MyD88 deficiency on murine brain structure during development and on behavior. In neonatal Myd88-/- mice, neocortical thickness was reduced, while density of cortical neurons was increased. In contrast, microglia, astrocyte, oligodendrocyte, and proliferating cell numbers were unchanged in these mice compared to wild-type mice. In adult Myd88-/- mice, neocortical thickness was unaltered, but neuronal density in neocortex and hippocampus was increased. Neuron arborization was less pronounced in adult Myd88-/- mice compared to wild-type animals. In addition, numbers of microglia and proliferating cells were increased in the neocortex and subventricular zone, respectively, with unaltered astrocyte and oligodendrocyte numbers, and myelinization was enhanced in the adult Myd88-/- neocortex. These morphologic changes in the brain of adult Myd88-/- mice were accompanied by specific behavioral traits, such as decreased locomotor activity, increased anxiety-like behavior, but normal day/light activity, satisfactory learning, short- and long-term spatial memory, potential cognitive inflexibility, and increased hanging and locomotor behavior within their home cage. Taken together, MyD88 deficiency results in morphologic and cellular changes in the mouse brain, as well as in altered natural and specific behaviors. Our data indicate a pathophysiological significance of MyD88 for mammalian CNS development, structure, and function.


Assuntos
Comportamento Animal , Encéfalo/patologia , Fator 88 de Diferenciação Mieloide , Proteínas Adaptadoras de Transdução de Sinal , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Receptores de Interleucina-1/metabolismo
4.
Ann Neurol ; 86(5): 656-670, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31325344

RESUMO

OBJECTIVE: Maternal autoantibodies are a risk factor for impaired brain development in offspring. Antibodies (ABs) against the NR1 (GluN1) subunit of the N-methyl-d-aspartate receptor (NMDAR) are among the most frequently diagnosed anti-neuronal surface ABs, yet little is known about effects on fetal development during pregnancy. METHODS: We established a murine model of in utero exposure to human recombinant NR1 and isotype-matched nonreactive control ABs. Pregnant C57BL/6J mice were intraperitoneally injected on embryonic days 13 and 17 each with 240µg of human monoclonal ABs. Offspring were investigated for acute and chronic effects on NMDAR function, brain development, and behavior. RESULTS: Transferred NR1 ABs enriched in the fetus and bound to synaptic structures in the fetal brain. Density of NMDAR was considerably reduced (up to -49.2%) and electrophysiological properties were altered, reflected by decreased amplitudes of spontaneous excitatory postsynaptic currents in young neonates (-34.4%). NR1 AB-treated animals displayed increased early postnatal mortality (+27.2%), impaired neurodevelopmental reflexes, altered blood pH, and reduced bodyweight. During adolescence and adulthood, animals showed hyperactivity (+27.8% median activity over 14 days), lower anxiety, and impaired sensorimotor gating. NR1 ABs caused long-lasting neuropathological effects also in aged mice (10 months), such as reduced volumes of cerebellum, midbrain, and brainstem. INTERPRETATION: The data collectively support a model in which asymptomatic mothers can harbor low-level pathogenic human NR1 ABs that are diaplacentally transferred, causing neurotoxic effects on neonatal development. Thus, AB-mediated network changes may represent a potentially treatable neurodevelopmental congenital brain disorder contributing to lifelong neuropsychiatric morbidity in affected children. ANN NEUROL 2019;86:656-670.


Assuntos
Autoanticorpos/toxicidade , Encéfalo/patologia , Efeitos Tardios da Exposição Pré-Natal , Receptores de N-Metil-D-Aspartato/imunologia , Animais , Autoantígenos/imunologia , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Deficiências do Desenvolvimento/imunologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Receptores de N-Metil-D-Aspartato/metabolismo
5.
J Am Chem Soc ; 140(29): 9219-9229, 2018 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-29949370

RESUMO

Structural modifications of molecular cobalt catalysts have provided important insights into the structure-function relationship for the hydrogen evolution reaction. We have shown that replacement of equatorial pyridines with more basic and conjugate isoquinoline groups of a pentadentate ligand results in lower overpotential and higher catalytic activity for electro- and photolytic H2 production in aqueous solutions. To fully understand the electronic and steric effects of the axial group that lies trans to the proposed cobalt hydride intermediate, isoquinoline groups were introduced in two new pentadentate ligands, N, N-bis(2-pyridinylmethyl)[3-(2-pyridinyl)isoquinoline)]-1-methanamine (DPA-1-MPI) and N, N-bis(2-pyridinylmethyl)[1-(2-pyridinyl)-isoquinoline)]-3-methanamine (DPA-3-MPI). Despite a slight structural difference of the introduced isoquinoline group, the resulting cobalt complexes display drastic changes in their electro- and photochemical properties. There are positive shifts of 290 and 260 mV, respectively, for the CoII/CoI and CoIII-H/CoII-H couples from [Co(DPA-1-MPI)(H2O)](PF6)3 to [Co(DPA-3-MPI)(H2O)](PF6)3, with the former being ∼32 times as active as the latter in photocatalytic H2 production. Density functional theory (DFT) calculations show that the protonation of CoI to yield the CoIII-H species is energetically more favorable for [Co(DPA-1-MPI)(H2O)](PF6)3 than that of [Co(DPA-3-MPI)(H2O)](PF6)3. Both experimental results and DFT computations suggest that the presence of a planar conjugate bipyridyl unit or its isoquinoline derivative is a key feature for stabilizing low valent CoI species toward proton binding. The incorporation of an electron-donating group trans to the proposed Co-H species also facilitates proton binding and H-H bond formation, which is proposed to occur by the heterolytic coupling of CoII-H species. The overall catalytic H2 evolution is presented as the modified electron transfer (E)-proton transfer (C)-electron transfer (E)-proton transfer (C) (mod-ECEC) pathway. This study provides important new insight into the electronic and steric factors controlling catalytic H2 production by Co complexes with pentadentate ligands.

7.
J Clin Psychol Med Settings ; 24(3-4): 245-258, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28929269

RESUMO

Behavioral health integration within primary care has been evolving, but literature traditionally focuses on smaller scale efforts. We detail how behavioral health has been integrated across a large, urban pediatric hospital system's six primary care clinics (serving over 35,000 children annually and insured predominately through Medicaid) and discuss strategies for success in sustaining and expanding efforts to achieve effective integration of behavioral health into primary care. In a time span of 3 years, the clinics have implemented routine, universal behavioral health screening at well child visits, participated in a 15-month behavioral health screening quality improvement learning collaborative, and integrated the work of psychologists and psychiatrists. Additional work remains to be done in improving family engagement, further expanding services, and ensuring sustainability.


Assuntos
Medicina do Comportamento/organização & administração , Prestação Integrada de Cuidados de Saúde/organização & administração , Hospitais Pediátricos/organização & administração , Atenção Primária à Saúde/organização & administração , Criança , Transtornos do Comportamento Infantil/diagnóstico , Transtornos do Comportamento Infantil/terapia , Pré-Escolar , District of Columbia , Diagnóstico Precoce , Intervenção Médica Precoce , Implementação de Plano de Saúde/organização & administração , Humanos , Comunicação Interdisciplinar , Colaboração Intersetorial , Programas de Rastreamento , Avaliação das Necessidades , Estados Unidos
9.
Autism ; : 13623613241260800, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907720

RESUMO

LAY ABSTRACT: Primary care providers often screen for autism during well child visits in the first few years of life and refer children for diagnostic evaluations when needed. However, most children do not receive a diagnosis until years later which delays access to services. Racism, socioeconomic status, and other systemic inequalities that limit access to health care further delay diagnostic evaluations. Mental health clinicians who work in primary care clinics can help address barriers to accessing diagnostic evaluation services once they are recommended by their primary care provider. However, mental health clinicians who work in primary care typically do not have training in diagnosing autism. The goal of this study was to evaluate a program training mental health professionals working in an urban primary care setting, primarily serving Black and Latinx families insured by Medicaid, to provide autism diagnostic evaluations. Two hundred and fifty children completed evaluations through the Autism in Primary Care (APC) program. The wait time to access an evaluation through APC was significantly shorter than through standard avenues of care (e.g. referring to a separate autism clinic). Referring primary care providers and caregivers endorsed high levels of satisfaction with the program. Conducting autism evaluations in primary care settings offers a promising opportunity to improve earlier diagnosis and treatment access for families, reduce inequities in care, and increase caregiver and child well-being.

10.
Clin Pediatr (Phila) ; 62(6): 584-591, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36457153

RESUMO

This study aimed to examine predictors of complete and elevated youth mental health screens. Parents of 4- to 11-year-old children completed the Strengths and Difficulties Questionnaire (SDQ) during a routine, universal mental health screening initiative in primary care. Bivariate logistic regressions were run to examine associations between independent (visit age, sex, race/ethnicity, language, insurance, and guardian) and dependent variables (screening completion and elevated SDQ score). Parents of younger and Spanish-speaking (vs English-speaking) children were less likely to have a complete SDQ screen. Among those with complete SDQ screens, older children, male children, those with public or no insurance, and those who had a mother (vs father) complete the screener were more likely to have an elevated score. Understanding patterns of screening completion rates and predictors of elevated screens provides valuable information to improve resource mapping and planning. Findings can inform mental health screening implementation and optimization within primary care.


Assuntos
Transtornos Mentais , Saúde Mental , Feminino , Adolescente , Criança , Humanos , Masculino , Pré-Escolar , Inquéritos e Questionários , Transtornos Mentais/diagnóstico , Programas de Rastreamento , Pais/psicologia , Atenção Primária à Saúde
11.
Psychiatr Serv ; 74(1): 66-69, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36004435

RESUMO

OBJECTIVE: This study examined predictors of readmission to a psychiatric inpatient unit of an urban children's hospital within 1 year of discharge among a racially diverse sample of youths. METHODS: The authors retrospectively analyzed 2 years of electronic health record data of inpatient psychiatric unit admissions (N=1,604). Multivariate logistic regression and random-effects multinomial logistic regression were used for analyses. RESULTS: The estimated odds ratios for any readmission within 1 year of discharge were significantly higher for Black youths, youths insured by Medicaid, and youths with a length of stay longer than 7 days. Factors remained strongly predictive when examining multiple readmissions versus no readmissions. CONCLUSIONS: Black youths, youths insured by Medicaid, and youths with longer stays were more likely than other youths to be readmitted. Findings suggest the need for interventions such as care coordination to target predictors of readmission and the need to examine inequities in the health care system.


Assuntos
Medicaid , Readmissão do Paciente , Criança , Estados Unidos , Humanos , Adolescente , Estudos Retrospectivos , Modelos Logísticos , Tempo de Internação , Fatores de Risco
12.
J Pediatr Health Care ; 37(3): 302-310, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36529554

RESUMO

INTRODUCTION: Child psychiatry access programs (CPAPs) provide primary care providers (PCPs) with assistance in mental health diagnosis, management, and resource navigation. METHOD: Data collected from DC Mental Health Access in Pediatrics (MAP) included PCPs and patient demographics, clinical encounter information, and provider satisfaction. RESULTS: DC MAP consult volume increased 349.3% over the first 5 years. Services requested included care coordination (85.8%), psychiatric consultation (21.4%), and psychology/social work consultation (9.9%). Of psychiatry-involved consultations, PCPs managed patient medication care with DC MAP support 50.5% of the time. Most (94.1%) PCPs said they would recommend colleagues use DC MAP, and 29.6% reported diverting patients from the emergency departments using DC MAP. DISCUSSION: DC MAP grew quickly, highlighting program impact and need. Demand for care coordination required flexible staffing and highlighted the need for coordination in pediatrics. Child psychiatry access programs offer an innovative way to enhance PCP management of their patients' mental health needs.


Assuntos
Transtornos Mentais , Serviços de Saúde Mental , Encaminhamento e Consulta , Humanos , Criança , Acessibilidade aos Serviços de Saúde , District of Columbia , Psiquiatria Infantil , Pediatria , Saúde Mental , Avaliação de Programas e Projetos de Saúde , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia
13.
Pediatrics ; 152(5)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37795558

RESUMO

Children with autism face significant barriers to accessing evaluations and intervention services often because of confusing referral processes, lack of centralized coordination across organizations serving children with autism, insurance coverage gaps, multiyear waitlists for diagnostic services, and limited provider knowledge about autism. Racism and systemic inequities exist and persist in autism care across the United States. This article reviews targeted initiatives implemented by a multidisciplinary team to advocate for, and address barriers faced, by autistic children and their families in Washington, DC. We describe initiatives across multiple levels of the health care system including: 1. infrastructure-building initiatives (eg, coalition-building, policy, and advocacy); 2. enabling services (eg, population- and community-level supports that increase provider capacity to serve children's and families' needs); and 3. direct services (eg, innovative, gap-filling programs that directly serve children and families). We review outcomes and describe lessons learned.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Criança , Humanos , Estados Unidos , Transtorno Autístico/diagnóstico , Transtorno Autístico/terapia , Atenção à Saúde
14.
JCI Insight ; 8(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37698934

RESUMO

Somatic gain-of-function mutations in the L-type calcium channel CaV1.3 (CACNA1D gene) cause adrenal aldosterone-producing adenomas and micronodules. De novo germline mutations are found in a syndrome of primary aldosteronism, seizures, and neurologic abnormalities (PASNA) as well as in autism spectrum disorder. Using CRISPR/Cas9, we here generated mice with a Cacna1d gain-of-function mutation found in both adenomas and PASNA syndrome (Cacna1dIle772Met/+). These mice show reduced body weight and increased mortality from weaning to approximately 100 days of age. Male mice do not breed, likely due to neuromotor impairment, and the offspring of female mice die perinatally, likely due to lack of maternal care. Mice generated by in vitro fertilization showed elevated intracellular calcium in the aldosterone-producing zona glomerulosa, an elevated aldosterone/renin ratio, and persistently elevated serum aldosterone on a high-salt diet as signs of primary aldosteronism. Anesthesia with ketamine and xylazine induced tonic-clonic seizures. Neurologic abnormalities included hyperlocomotion, impaired performance in the rotarod test, impaired nest building, and slight changes in social behavior. Intracellular calcium in the zona glomerulosa, aldosterone levels, and rotarod performance responded to treatment with the calcium channel blocker isradipine, with implications for the therapy of patients with aldosterone-producing lesions and with PASNA syndrome.


Assuntos
Adenoma , Transtorno do Espectro Autista , Hiperaldosteronismo , Humanos , Masculino , Feminino , Camundongos , Animais , Aldosterona , Hiperaldosteronismo/tratamento farmacológico , Hiperaldosteronismo/genética , Isradipino , Cálcio , Mutação , Convulsões
16.
Pediatrics ; 148(6)2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34814188

RESUMO

Perinatal mood and anxiety disorders (PMADs) are the most common complication of childbirth, with suicide a leading cause of postpartum deaths. PMADs are associated with poor maternal, infant, and family outcomes. Identification and early intervention are imperative for successful treatment. This case study describes the implementation and outcomes of a multidisciplinary Perinatal Mental Health Task Force ("Task Force") at one urban academic children's hospital that was created to promote systems change and health care policy solutions for improved identification and treatment of PMADs. Using the social ecological model as a framework, the Task Force addressed care at the individual, interpersonal, organizational, community, and policy levels. The Task Force applied lessons learned from division-specific screening initiatives to create best practices and make hospital-wide recommendations. This foundational work enabled us to build community bridges and break down internal barriers to shift our pediatric hospital toward prioritizing perinatal mental health. As a result, screening expanded to multiple hospital locations and became a hospital corporate goal, the Perinatal Mental Health Screening Tool Kit was created and disseminated within the community, Task Force members testified in governmental hearings and joined national organizations to inform policy, and Task Force and community collaborations resulted in significant grant funding. Lessons learned have been disseminated nationally. Moving forward, we aim to expand our program and partnerships to ensure that caregivers of infants receive appropriate mental health support to strengthen family well-being. The Task Force can serve as a model for advocates looking to expand and integrate PMAD care.


Assuntos
Comitês Consultivos/organização & administração , Transtornos de Ansiedade/diagnóstico , Transtornos do Humor/diagnóstico , Transtornos Puerperais/diagnóstico , Transtornos de Ansiedade/terapia , District of Columbia , Intervenção Médica Precoce/organização & administração , Serviço Hospitalar de Emergência , Feminino , Hospitais Pediátricos , Humanos , Unidades de Terapia Intensiva Neonatal , Saúde Mental , Transtornos do Humor/terapia , Desenvolvimento de Programas , Transtornos Puerperais/terapia
17.
J Dev Behav Pediatr ; 42(1): 32-40, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32796400

RESUMO

OBJECTIVE: Despite the utility of universal screening, most pediatric providers rarely use mental health (MH) screening tools. As such, provider descriptions of their experiences with universal screening are limited. The goal of this study was to describe barriers to, and facilitators of, universal MH screening implementation, the perceived impact of such screening, impressions of a screening-focused quality improvement (QI) Learning Collaborative, and lessons learned. METHOD: We invited primary care clinicians participating in a large-scale QI Learning Collaborative on MH screening (n = 107) to complete postproject interviews. Interviews were transcribed and analyzed using constant comparative qualitative analysis, an inductive, iterative process. RESULTS: Eleven interviews were completed and analyzed. Practice sites included academic health centers, a private practice, and a federally qualified health center. Providers described the positive impact of screening (increased identification of MH concerns) and barriers and facilitators of screening at the practice level (clinic and leadership buy-in and electronic medical record integration), the provider level (provider beliefs about the importance of screening), and the patient level (parent literacy). Challenges of linking families with care after screening included lack of adequate referrals, long wait lists, limited bilingual providers, insurance gaps, and inadequate feedback loops. Access to on-site MH clinicians and participation in the Learning Collaborative were described as beneficial. CONCLUSION: Findings elucidate how universal MH screening can be sustainably integrated into real-world primary care settings and may facilitate the uptake of American Academy of Pediatrics recommendations for best practices in screening for MH concerns.


Assuntos
Saúde Mental , Pediatria , Criança , Humanos , Programas de Rastreamento , Atenção Primária à Saúde , Encaminhamento e Consulta
18.
Circ Res ; 102(4): 465-71, 2008 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-18096820

RESUMO

Since the first description of the anatomical atrioventricular nodes (AVNs), a large number of studies have provided insights into the heterogeneity of the structure as well as a repertoire of ion channel proteins that govern this complex conduction pathway between the atria and ventricles. These studies have revealed the intricate organization of multiple nodal and nodal-like myocytes contributing to the unique electrophysiology of the AVN in health and diseases. On the other hand, information regarding the contribution of specific ion channels to the function of the AVN remains incomplete. We reason that the identification of AVN-specific ion channels may provide a more direct and rational design of therapeutic target in the control of AVN conduction in atrial flutter/fibrillation, one of the most common arrhythmias seen clinically. In this study, we took advantage of 2 genetically altered mouse models with overexpression or null mutation of 1 of a small conductance Ca2+-activated K+ channel isoform, SK2 channel, and demonstrated robust phenotypes of AVN dysfunction in these experimental models. Overexpression of SK2 channels results in the shortening of the spontaneous action potentials of the AVN cells and an increase in the firing frequency. On the other hand, ablation of the SK2 channel results in the opposite effects on the spontaneous action potentials of the AVN. Furthermore, we directly documented the expression of SK2 channel in mouse AVN using multiple techniques. The new insights may have important implications in providing novel drug targets for the modification of AVN conduction in the treatment of atrial arrhythmias.


Assuntos
Arritmias Cardíacas/fisiopatologia , Nó Atrioventricular/fisiologia , Canais de Potássio Ativados por Cálcio de Condutância Baixa/genética , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Potenciais de Ação/fisiologia , Animais , Arritmias Cardíacas/genética , Nó Atrioventricular/citologia , Eletrocardiografia , Imunofluorescência , Expressão Gênica/fisiologia , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Técnicas de Patch-Clamp , Nó Sinoatrial/citologia , Nó Sinoatrial/fisiologia
19.
Anticancer Res ; 29(1): 299-302, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19331165

RESUMO

BACKGROUND: Therapeutic uses of asparaginases (ASNase) have been shown to elicit immune responses resulting in the development of potentially life-threatening human anti-bacterial antibodies (Ab). A robust screening enzyme-linked immunosorbent assay (ELISA) to detect binding Ab(+) against ASNase has been developed and validated for therapeutic monitoring to support clinical trials. Recently, a protein chip bioassay (Biacore) was developed for the Ab of these proteins. These methods were compared. MATERIALS AND METHODS: A Biacore T-100 analyzer using a protein bioassay and an ELISA assay were used to determine the IgG immmuboglobulin Ab against ASNase in sera from 84 acute lymphoblastic leukemia (ALL) patients plus 6 controls (n=121 samples). These samples were characterized for anti-ASNase Ab neutralizing activity. Human E. coli ASNase, pegaspargase and Erwinase proteins were covalently coupled to the carboxy-methylated dextran matrix of a CM5 sensor chip (surface plasmon resonance, SPR). In the course of a nested experimental design, a wide range of human sera from patients who had obvious clinical allergic reactions after either native or pegaspargase treatments were tested. The data were fitted by a parametric logistic equation (+/-95% confidence interval, CI), which ranged from <3.0% to <14%. RESULTS: The specificity of Ab(+) was evaluated using "spiked" human IgG antibodies. Both assays provide near excellent linearity and sensitivity of response (<0.8 to <500 ratio and 1-3000 resonance units [RU]) of anti-ASNase Ab in human sera with low variance. The bioassay method was ten times more sensitive than the ELISA Ab assay. The lowest limit of quantification of Ab(+) ratio for the SPR assay was 0.6 whereas the upper limit of quantification was 3000 RU. The SPR assay results were in excellent accord with both the Ab(-) and the Ab(+). Ab(-) by the ELISA method (<1.003 ratio) was related to a mean RU value of 8.1. Despite the narrow range of ambiguity around the 1.1 Ab(+) ratio values, the majority of the specimens (93.2%) were determined to be Ab(+) by either ELISA or SPR determination. CONCLUSION: The vast majority (81/84 = 96.4%) of the IgG Ab(+) were neutralizing. The SPR Ab determination technique is reliable, accurate and more sensitive than the ELISA method.


Assuntos
Asparaginase/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Imunoglobulina G/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Ressonância de Plasmônio de Superfície/métodos , Adulto , Asparaginase/efeitos adversos , Asparaginase/uso terapêutico , Criança , Erwinia/enzimologia , Escherichia coli/enzimologia , Humanos , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Análise Serial de Proteínas/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
J Food Prot ; 72(8): 1713-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19722406

RESUMO

The present study examined the incidence of Escherichia coli O:H7 and Salmonella in feedlot lambs. Fifty-six feedlot lambs from eight sheep farming operations were grouped in a single drylot pen, fed, and managed as is typical in the southwestern United States. Fecal samples were collected on days 0, 46, 87, and 122 of the feeding period via rectal palpation. Wool samples (ventral midline) were collected one time only at the feedlot, immediately prior to shipping to the processing plant, and carcass swabs were collected following slaughter. All samples were cultured for E. coli O157:H7, Salmonella, and fecal coliforms, and select isolates were examined for antimicrobial susceptibility. Overall, the percentages of fecal and wool samples positive for E. coli O157:H7 averaged 9 and 18%, respectively. One carcass swab was E. coli O157:H7 positive. Of the 155 fecal samples collected, 11 (7%) were Salmonella positive. Salmonella was detected in nearly 50% of the wool samples collected prior to slaughter, while none of the carcasses were Salmonella positive 24 h postslaughter. All isolates (E. coli O157:H7, Salmonella, and fecal coliforms) were susceptible to ceftiofur, enrofloxacin, and trimethoprim-sulfamethoxazole. One E. coli O157:H7 isolate cultured from a carcass swab was resistant to seven antibiotics, and seven wool E. coli O157:H7 isolates were multidrug resistant. Results of this research demonstrate that feedlot sheep are naturally colonized with E. coli O157:H7 and Salmonella and wool can be a source of carcass contamination; however, in-plant processing procedures and intervention strategies were largely effective in preventing carcass contamination.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli O157/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Ovinos/microbiologia , Animais , Animais Recém-Nascidos , Contagem de Colônia Microbiana , Farmacorresistência Bacteriana Múltipla , Fezes/microbiologia , Contaminação de Alimentos/prevenção & controle , Testes de Sensibilidade Microbiana , Prevalência , Salmonella/isolamento & purificação , Lã/microbiologia
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