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1.
Front Pain Res (Lausanne) ; 4: 1197374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404692

RESUMO

Though long-sought, transformation of pain management practice and culture has yet to be realized. We propose both a likely cause-entrenchment in a biomedical model of care that is observed and then replicated by trainees-and a solution: deliberately leveraging the hidden curriculum to instead implement a sociopsychobiological (SPB) model of care. We make use of Implicit Bias Recognition and Management, a tool that helps teams to first recognize and "surface" whatever is implicit and to subsequently intervene to change whatever is found to be lacking. We describe how a practice might use iterations of recognition and intervention to move from a biomedical to a SPB model by providing examples from the Chronic Pain Wellness Center in the Phoenix Veterans Affairs Health Care System. As pain management practitioners and educators collectively leverage the hidden curriculum to provide care in the SPB model, we will not only positively transform our individual practices but also pain management as a whole.

2.
EMBO J ; 42(16): e113616, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37317646

RESUMO

Cilia are cellular projections that perform sensory and motile functions in eukaryotic cells. A defining feature of cilia is that they are evolutionarily ancient, yet not universally conserved. In this study, we have used the resulting presence and absence pattern in the genomes of diverse eukaryotes to identify a set of 386 human genes associated with cilium assembly or motility. Comprehensive tissue-specific RNAi in Drosophila and mutant analysis in C. elegans revealed signature ciliary defects for 70-80% of novel genes, a percentage similar to that for known genes within the cluster. Further characterization identified different phenotypic classes, including a set of genes related to the cartwheel component Bld10/CEP135 and two highly conserved regulators of cilium biogenesis. We propose this dataset defines the core set of genes required for cilium assembly and motility across eukaryotes and presents a valuable resource for future studies of cilium biology and associated disorders.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Humanos , Caenorhabditis elegans/genética , Filogenia , Cílios/genética , Proteínas de Drosophila/genética
4.
Reg Anesth Pain Med ; 46(12): 1100-1102, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34489354

RESUMO

BACKGROUND: Cerebral spinal fluid (CSF) dynamics are complex and changes in spinal anatomy may influence the rostrocaudal movement of intrathecal medications. We present the first reported case demonstrating that acute cervical spinal stenosis may impede the distribution of adjacent intrathecal medications, and that correction of such stenosis and the resulting changes in CSF flow may necessitate significant adjustments in the intrathecal infusates. CASE PRESENTATION: We present a case of a 60-year-old male patient with a cervicothoracic intrathecal pump (ITP) infusing morphine, bupivacaine, and baclofen for chronic neck pain. The alert and oriented patient had a recent fall resulting in an acute severe cervical stenosis and cord compression which required urgent surgical decompression. Postoperatively, after the cervical decompression, the patient had significant altered mental status requiring a naloxone infusion. Multiple attempts to reduce the naloxone infusion were initially not successful due to worsened somnolence. The previously tolerated ITP medications were continuously reduced over the next 14 days, allowing concomitant decrease and eventual cessation of the naloxone infusion while maintaining patient mental status. The only opioids the patient received during this period were from the ITP. CONCLUSIONS: This case presents clinical evidence that severe spinal stenosis may impede the rostral CSF distribution of intrathecal medications. Intrathecal medications previously tolerated by patients prior to decompression may need to be significantly reduced in the postoperative period.


Assuntos
Estenose Espinal , Analgésicos Opioides/uso terapêutico , Bupivacaína/uso terapêutico , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Constrição Patológica/tratamento farmacológico , Humanos , Injeções Espinhais , Masculino , Pessoa de Meia-Idade , Morfina/uso terapêutico , Naloxona/uso terapêutico , Estenose Espinal/complicações , Estenose Espinal/diagnóstico por imagem
5.
J Cell Biol ; 216(6): 1659-1671, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28411189

RESUMO

Cilia are cellular projections that assemble on centriole-derived basal bodies. While cilia assembly is absolutely dependent on centrioles, it is not known to what extent they contribute to downstream events. The nematode C. elegans provides a unique opportunity to address this question, as centrioles do not persist at the base of mature cilia. Using fluorescence microscopy and electron tomography, we find that centrioles degenerate early during ciliogenesis. The transition zone and axoneme are not completely formed at this time, indicating that cilia maturation does not depend on intact centrioles. The hydrolethalus syndrome protein HYLS-1 is the only centriolar protein known to remain at the base of mature cilia and is required for intraflagellar transport trafficking. Surprisingly, targeted degradation of HYLS-1 after initiation of ciliogenesis does not affect ciliary structures. Taken together, our results indicate that while centrioles are essential to initiate cilia formation, they are dispensable for cilia maturation and maintenance.


Assuntos
Corpos Basais/fisiologia , Caenorhabditis elegans/fisiologia , Centríolos/fisiologia , Neurogênese , Células Receptoras Sensoriais/fisiologia , Animais , Animais Geneticamente Modificados , Axonema/fisiologia , Corpos Basais/metabolismo , Corpos Basais/ultraestrutura , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/ultraestrutura , Proteínas de Caenorhabditis elegans/metabolismo , Centríolos/metabolismo , Centríolos/ultraestrutura , Cílios/fisiologia , Tomografia com Microscopia Eletrônica , Microscopia de Fluorescência , Microscopia de Vídeo , Proteólise , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/ultraestrutura , Fatores de Tempo , Imagem com Lapso de Tempo
6.
EMBO J ; 35(19): 2139-2151, 2016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27491543

RESUMO

In budding yeast, the monopolin complex mediates sister kinetochore cross-linking and co-orientation in meiosis I. The CK1δ kinase Hrr25 is critical for sister kinetochore co-orientation, but its roles are not well understood. Here, we present the structures of Hrr25 and its complex with the monopolin subunit Mam1. Hrr25 possesses a "central domain" that packs tightly against the kinase C-lobe, adjacent to the binding site for Mam1. Together, the Hrr25 central domain and Mam1 form a novel, contiguous embellishment to the Hrr25 kinase domain that affects Hrr25 conformational dynamics and enzyme kinetics. Mam1 binds a hydrophobic surface on the Hrr25 N-lobe that is conserved in CK1δ-family kinases, suggesting a role for this surface in recruitment and/or regulation of these enzymes throughout eukaryotes. Finally, using purified proteins, we find that Hrr25 phosphorylates the kinetochore receptor for monopolin, Dsn1. Together with our new structural insights into the fully assembled monopolin complex, this finding suggests that tightly localized Hrr25 activity modulates monopolin complex-kinetochore interactions through phosphorylation of both kinetochore and monopolin complex components.


Assuntos
Caseína Quinase I/química , Caseína Quinase I/metabolismo , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/metabolismo , Fosfotransferases/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Caseína Quinase I/isolamento & purificação , Proteínas de Ciclo Celular/isolamento & purificação , Proteínas Cromossômicas não Histona/metabolismo , Cristalografia por Raios X , Modelos Moleculares , Fosforilação , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional , Proteínas de Saccharomyces cerevisiae/isolamento & purificação
7.
Elife ; 42015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25918846

RESUMO

The AAA+ family ATPase TRIP13 is a key regulator of meiotic recombination and the spindle assembly checkpoint, acting on signaling proteins of the conserved HORMA domain family. Here we present the structure of the Caenorhabditis elegans TRIP13 ortholog PCH-2, revealing a new family of AAA+ ATPase protein remodelers. PCH-2 possesses a substrate-recognition domain related to those of the protein remodelers NSF and p97, while its overall hexameric architecture and likely structural mechanism bear close similarities to the bacterial protein unfoldase ClpX. We find that TRIP13, aided by the adapter protein p31(comet), converts the HORMA-family spindle checkpoint protein MAD2 from a signaling-active 'closed' conformer to an inactive 'open' conformer. We propose that TRIP13 and p31(comet) collaborate to inactivate the spindle assembly checkpoint through MAD2 conformational conversion and disassembly of mitotic checkpoint complexes. A parallel HORMA protein disassembly activity likely underlies TRIP13's critical regulatory functions in meiotic chromosome structure and recombination.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/enzimologia , Proteínas de Ciclo Celular/metabolismo , Proteínas Mad2/metabolismo , Fuso Acromático/enzimologia , ATPases Associadas a Diversas Atividades Celulares , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/classificação , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Cristalografia por Raios X , Endopeptidase Clp/química , Endopeptidase Clp/genética , Endopeptidase Clp/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Expressão Gênica , Humanos , Pontos de Checagem da Fase M do Ciclo Celular , Proteínas Mad2/química , Proteínas Mad2/genética , Modelos Moleculares , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Proteínas Sensíveis a N-Etilmaleimida/química , Proteínas Sensíveis a N-Etilmaleimida/genética , Proteínas Sensíveis a N-Etilmaleimida/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Filogenia , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
8.
Dev Cell ; 31(4): 487-502, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25446517

RESUMO

Proteins of the HORMA domain family play central, but poorly understood, roles in chromosome organization and dynamics during meiosis. In Caenorhabditis elegans, four such proteins (HIM-3, HTP-1, HTP-2, and HTP-3) have distinct but overlapping functions. Through combined biochemical, structural, and in vivo analysis, we find that these proteins form hierarchical complexes through binding of their HORMA domains to cognate peptides within their partners' C-terminal tails, analogous to the "safety belt" binding mechanism of Mad2. These interactions are critical for recruitment of HIM-3, HTP-1, and HTP-2 to chromosome axes. HTP-3, in addition to recruiting the other HORMA domain proteins to the axis, plays an independent role in sister chromatid cohesion and double-strand break formation. Finally, we find that mammalian HORMAD1 binds a motif found both at its own C terminus and at that of HORMAD2, indicating that this mode of intermolecular association is a conserved feature of meiotic chromosome structure in eukaryotes.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Ciclo Celular/metabolismo , Pareamento Cromossômico/genética , Cromossomos/metabolismo , Meiose/fisiologia , Complexo Sinaptonêmico/metabolismo , Animais , Caenorhabditis elegans/citologia , Segregação de Cromossomos/fisiologia , Mutação/genética
9.
Hum Mol Genet ; 21(4): 799-810, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22068588

RESUMO

Neurological symptoms in tuberous sclerosis complex (TSC) and associated brain lesions are thought to arise from abnormal embryonic neurogenesis due to inherited mutations in Tsc1 or Tsc2. Neurogenesis persists postnatally in the human subventricular zone (SVZ) where slow-growing tumors containing Tsc-mutant cells are generated in TSC patients. However, whether Tsc-mutant neurons from the postnatal SVZ contribute to brain lesions and abnormal circuit remodeling in forebrain structures remain unexplored. Here, we report the formation of olfactory lesions following conditional genetic Tsc1 deletion in the postnatal SVZ using transgenic mice or targeted single-cell electroporation. These lesions include migratory heterotopias and olfactory micronodules containing neurons with a hypertrophic dendritic tree. Most significantly, our data identify migrating glial and neuronal precursors that are re-routed and infiltrate forebrain structures (e.g. cortex) and become glia and neurons. These data show that Tsc1-mutant cells from the neonatal and juvenile SVZ generate brain lesions and structural abnormalities, which would not be visible using conventional non-invasive imaging. These findings also raise the hypothesis that micronodules and the persistent infiltration of cells to forebrain structures may contribute to network malfunction leading to progressive neuropsychiatric symptoms in TSC.


Assuntos
Córtex Cerebral/patologia , Deleção de Genes , Neurogênese , Bulbo Olfatório/patologia , Heterotopia Nodular Periventricular/patologia , Proteínas Supressoras de Tumor/deficiência , Animais , Animais Recém-Nascidos , Movimento Celular , Dendritos/patologia , Eletroporação , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neuroglia/citologia , Neurônios/citologia , Análise de Célula Única , Serina-Treonina Quinases TOR/metabolismo , Esclerose Tuberosa/patologia , Proteína 1 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética
10.
J Clin Invest ; 121(4): 1596-607, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21403402

RESUMO

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by mutations in Tsc1 or Tsc2 that lead to mammalian target of rapamycin (mTOR) hyperactivity. Patients with TSC suffer from intractable seizures resulting from cortical malformations known as tubers, but research into how these tubers form has been limited because of the lack of an animal model. To address this limitation, we used in utero electroporation to knock out Tsc1 in selected neuronal populations in mice heterozygous for a mutant Tsc1 allele that eliminates the Tsc1 gene product at a precise developmental time point. Knockout of Tsc1 in single cells led to increased mTOR activity and soma size in the affected neurons. The mice exhibited white matter heterotopic nodules and discrete cortical tuber-like lesions containing cytomegalic and multinucleated neurons with abnormal dendritic trees resembling giant cells. Cortical tubers in the mutant mice did not exhibit signs of gliosis. Furthermore, phospho-S6 immunoreactivity was not upregulated in Tsc1-null astrocytes despite a lower seizure threshold. Collectively, these data suggest that a double-hit strategy to eliminate Tsc1 in discrete neuronal populations generates TSC-associated cortical lesions, providing a model to uncover the mechanisms of lesion formation and cortical hyperexcitability. In addition, the absence of glial reactivity argues against a contribution of astrocytes to lesion-associated hyperexcitability.


Assuntos
Córtex Cerebral/anormalidades , Convulsões/etiologia , Esclerose Tuberosa/etiologia , Proteínas Supressoras de Tumor/deficiência , Animais , Astrócitos/patologia , Sequência de Bases , Tamanho Celular , Córtex Cerebral/embriologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Primers do DNA/genética , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Camundongos Transgênicos , Gravidez , Convulsões/fisiopatologia , Serina-Treonina Quinases TOR/metabolismo , Esclerose Tuberosa/embriologia , Esclerose Tuberosa/genética , Esclerose Tuberosa/fisiopatologia , Proteína 1 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética
11.
AAPS PharmSciTech ; 11(4): 1650-61, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21107774

RESUMO

Vitamin B(3) is made up of niacin (nicotinic acid) and its amide, niacinamide. Both have equivalent vitamin activity, but only niacin (not niacinamide) is effective in lowering elevated low-density lipoprotein cholesterol and triglyceride levels in the blood. Administration of an extended-release (ER) oral tablet would frequently encounter food. If hydrogel is used to formulate the matrix of a biopharmaceutical classification system I drug (high solubility and high permeability), the dosage form absorbs water and swells.. The softened outer layer may be slashed off by food present in the stomach, thus, exposing the core tablet more readily for water absorption and speeding up drug release from its original designed rate. This project aimed to formulate niacin CR pellets made of hydrophobic inert matrix. After niacin was melted with excipients and cooled, the mass was extruded and spheronized into pellets. Size distribution and flowability were determined before pellets were filled into hard gelatin capsule. The USP dissolution study revealed that a candidate formulation of 250 mg in strength released similar amount of niacin as its commercial reference, niacin controlled-release 500 mg tablet, in 6 h (223.9 ± 23.8 mg, n = 4 versus 259.4 ± 2.6 mg, n = 3). The differential scanning calorimetry study of the pellets in capsules stored in 40°C for 4 weeks, and the content assay of capsules in 40°C up to 6 months suggested that niacin was stable within the innovative formulation. In vitro release from this innovative ER capsules stored at 40°C up to 4 weeks were also investigated.


Assuntos
Química Farmacêutica/métodos , Preparações de Ação Retardada , Excipientes/química , Hipolipemiantes/química , Niacina/química , Cápsulas , Composição de Medicamentos , Estabilidade de Medicamentos , Hipolipemiantes/administração & dosagem , Modelos Químicos , Niacina/administração & dosagem , Medicamentos sem Prescrição , Reologia , Solubilidade
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