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1.
Chemphyschem ; : e202400669, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39292526

RESUMO

There is growing interest in the electronic properties of metalloporphyrins especially in relation to their interactions with other molecular species in their local environment. Here, UV-VIS laser photodissociation spectroscopy in vacuo has been applied to an iron-centred metalloporphyrin (FeTPP+) and its N-aromatic adduct with pyridine (py) to determine the electronic effect of complexation. Both the metalloporphyrin (FeTPP+) and pyridine adduct (FeTPP+⋅py) absorb strongly across the spectral region studied (652-302 nm: 1.91-4.10 eV). Notably, a large blue shift was observed for the dominant Soret band (41 nm) upon complexation (0.47 ± 0.02 eV), indicative of strong pyridine binding. Significant differences in the profiles (i.e. number and position of bands) of the electronic spectra are evident comparing FeTPP+ and FeTPP+⋅py. Time-dependent density functional theory calculations were used to assign the spectra, revealing that the FeIII spin-state flips from S = 3/2 to S = 5/2 upon complexation with pyridine. For FeTPP+, all bright spectral transitions are found to be π-π* in character, with electron density variously distributed across the porphyrin and/or its phenyl substituents. Similar electronic excitations are observed for FeTPP+⋅py, with an additional bright transition which involves charge transfer from the porphyrin to the pyridine moiety.

2.
J Couns Psychol ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39115906

RESUMO

This article introduces the integrated behavioral model of mental health help seeking (IBM-HS), a theoretical model for understanding the constructs (e.g., systemic, predisposing, and enabling factors; mental health literacy; illness perceptions; perceived need; stigma; shame; perceived benefits, motivation) that influence people's decision making around seeking professional mental health care and their ultimate access to formal treatment. The IBM-HS is a help-seeking-specific adaptation of the empirically supported integrated behavioral model and integrative model, which are themselves evolutions of the theory of planned behavior and theory of reasoned action. The IBM-HS posits that help-seeking determinants (e.g., structural forces; cultural influences; past help-seeking experience; evaluated need; mental health perceptions, knowledge, and skills; social support) influence help-seeking beliefs (i.e., outcome beliefs, experiential beliefs, beliefs about others' expectations, beliefs about others' behavior, logistical beliefs), which in turn determine their respective help-seeking mechanisms (i.e., attitude, perceived norm, personal agency). These mechanisms collectively influence help-seeking intention, which drives prospective help-seeking behavior, subject to the moderating effects of determinants. Finally, prospective behavior has reciprocal feedback loop effects on certain determinants and beliefs. This article describes the need for the IBM-HS, the model's constructs and their interrelations, measurement considerations, and how the model can be used by scholarly and applied users to systematically understand people's intention to seek professional mental health care services and what helps or hinders them from utilizing this care. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

3.
J Neurosci ; 38(40): 8515-8525, 2018 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-30108130

RESUMO

Whether synapses in appetite-regulatory brain regions undergo long-term changes in strength in response to satiety peptides is poorly understood. Here we show that following bursts of afferent activity, the neuromodulator and satiety peptide cholecystokinin (CCK) shifts the plasticity of GABA synapses in the dorsomedial nucleus of the hypothalamus of male Sprague Dawley rats from long-term depression to long-term potentiation (LTP). This LTP requires the activation of both type 2 CCK receptors and group 5 metabotropic glutamate receptors, resulting in a rise in astrocytic intracellular calcium and subsequent ATP release. ATP then acts on presynaptic P2X receptors to trigger a prolonged increase in GABA release. Our observations demonstrate a novel form of CCK-mediated plasticity that requires astrocytic ATP release, and could serve as a mechanism for appetite regulation.SIGNIFICANCE STATEMENT Satiety peptides, like cholecystokinin, play an important role in the central regulation of appetite, but their effect on synaptic plasticity is not well understood. The current data provide novel evidence that cholecystokinin shifts the plasticity from long-term depression to long-term potentiation at GABA synapses in the rat dorsomedial nucleus of the hypothalamus. We also demonstrate that this plasticity requires the concerted action of cholecystokinin and glutamate on astrocytes, triggering the release of the gliotransmitter ATP, which subsequently increases GABA release from neighboring inhibitory terminals. This research reveals a novel neuropeptide-induced switch in the direction of synaptic plasticity that requires astrocytes, and could represent a new mechanism by which cholecystokinin regulates appetite.


Assuntos
Trifosfato de Adenosina/metabolismo , Astrócitos/fisiologia , Colecistocinina/fisiologia , Núcleo Hipotalâmico Dorsomedial/fisiologia , Potenciação de Longa Duração , Depressão Sináptica de Longo Prazo , Ácido gama-Aminobutírico/fisiologia , Animais , Masculino , Ratos Sprague-Dawley , Receptor de Glutamato Metabotrópico 5/fisiologia , Receptores da Colecistocinina/fisiologia , Receptores Purinérgicos P2X/fisiologia , Transmissão Sináptica
4.
Subst Use Misuse ; 48(14): 1553-62, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23822739

RESUMO

In 2008-2009, we conducted a 6-week, open-label trial of transdermal nicotine replacement therapy and practical counseling for 34 adolescents seeking smoking cessation in Los Angeles. Dependent outcomes were study retention, use of the patch, and 7-day quit status at the end-of-study and at follow-up visits. Predictors of outcomes included cigarette dependence, withdrawal symptoms, demographic and psychiatric measures, and other substance use. Variables significant in bivariate analysis (p < .10) were retained in a multivariate model. Subjects had significant pre-to-post reductions in quit rates, dependence, and withdrawal symptoms. Subjects also reported a high number of comorbidities. Implications for clinicians are discussed.


Assuntos
Terapia Cognitivo-Comportamental , Nicotina/uso terapêutico , Abandono do Hábito de Fumar/métodos , Dispositivos para o Abandono do Uso de Tabaco , Adolescente , Feminino , Humanos , Los Angeles , Masculino , Motivação , Abandono do Hábito de Fumar/psicologia , Resultado do Tratamento , Adulto Jovem
5.
J Am Vet Med Assoc ; 261(11): 1-6, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37468124

RESUMO

OBJECTIVE: To determine the presentation, diagnosis, progression, and family risk of fibrotic myopathy, a disease with marked breed predisposition in the German Shepherd Dog (GSD). ANIMALS: 41 dogs prospectively recruited to the University of Wisconsin-Madison Comparative Genetics and Orthopedic Laboratory between November 2019 to August 2022. METHODS: Medical records of dogs diagnosed with fibrotic myopathy were reviewed upon referral. The following data were recorded: sex, age, weight, regio interscapularis (withers) height, date of neutering, coat color and length, and age at fibrotic myopathy diagnosis. A pedigree was also obtained. RESULTS: In the study population, breeds included 37 GSDs, a Belgian Malinois, a Belgian Malinois cross, and 2 dogs with a GSD phenotype and no pedigree. Mean age at fibrotic myopathy diagnosis was 5.9 ± 2.0 years, and duration of lameness before diagnosis was 5.6 months and ranged from 0.75 to 18 months. Males were overrepresented at 61% of the study population. Inherited familial risk for fibrotic myopathy in the GSD was supported by pedigree analysis. CLINICAL RELEVANCE: This was the largest case series of fibrotic myopathy to date, providing a more comprehensive look at presentation and progression of the disease. The longer duration of lameness in bilaterally affected dogs likely represents disease progression rather than a more severe phenotype. Family history data support a genetic contribution to fibrotic myopathy, suggesting that further genetic investigation is warranted.


Assuntos
Contratura , Doenças do Cão , Doenças Musculares , Humanos , Masculino , Cães , Animais , Estudos Prospectivos , Coxa da Perna , Coxeadura Animal , Doenças Musculares/genética , Doenças Musculares/veterinária , Contratura/genética , Contratura/veterinária , Doenças do Cão/genética
6.
Plant Biotechnol J ; 10(3): 249-68, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22059985

RESUMO

Plant cell culture systems were initially explored for use in commercial synthesis of several high-value secondary metabolites, allowing for sustainable production that was not limited by the low yields associated with natural harvest or the high cost associated with complex chemical synthesis. Although there have been some commercial successes, most notably paclitaxel production from Taxus sp., process limitations exist with regards to low product yields and inherent production variability. A variety of strategies are being developed to overcome these limitations including elicitation, in situ product removal and metabolic engineering with single genes and transcription factors. Recently, the plant cell culture production platform has been extended to pharmaceutically active heterologous proteins. Plant systems are beneficial because they are able to produce complex proteins that are properly glycosylated, folded and assembled without the risk of contamination by toxins that are associated with mammalian or microbial production systems. Additionally, plant cell culture isolates transgenic material from the environment, allows for more controllable conditions over field-grown crops and promotes secretion of proteins to the medium, reducing downstream purification costs. Despite these benefits, the increase in cost of heterologous protein synthesis in plant cell culture as opposed to field-grown crops is significant and therefore processes must be optimized with regard to maximizing secretion and enhancing protein stability in the cell culture media. This review discusses recent advancements in plant cell culture processing technology, focusing on progress towards overcoming the problems associated with commercialization of these production systems and highlighting recent commercial successes.


Assuntos
Técnicas de Cultura de Células/métodos , Células Vegetais/metabolismo , Plantas/metabolismo , Benzaldeídos/síntese química , Reatores Biológicos , Técnicas de Cultura de Células/normas , Meios de Cultura/metabolismo , Regulação da Expressão Gênica , Vetores Genéticos/metabolismo , Engenharia Metabólica/métodos , Paclitaxel/biossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plantas/genética , Estabilidade Proteica
7.
Diagn Microbiol Infect Dis ; 102(4): 115631, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35045382

RESUMO

One SARS-CoV-2-positive sample demonstrated impaired detection of the N1 target by RT-PCR using US CDC primer/probe sets. A 3 nucleotide deletion was discovered that overlaps the forward primer binding site. This finding underscores the importance of continued SARS-CoV-2 mutation surveillance and assessment of the impact on diagnostic test performance.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Primers do DNA/genética , Humanos , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/genética , Sensibilidade e Especificidade
8.
Metabolites ; 11(10)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34677403

RESUMO

Plant cell cultures derived from Taxus are used to produce valuable metabolites like paclitaxel, a chemotherapeutic drug. Methyl jasmonate elicitation enhances paclitaxel accumulation, but also inhibits culture growth and increases phenylpropanoid biosynthesis, two side effects that detract from taxane accumulation. To understand the connection between all of these processes, a systems approach is applied to investigate cell-wide metabolism in Taxus. Non-paclitaxel and paclitaxel accumulating cultures were elicited over single and multi-generational periods, and subsequent changes in conserved and specialized metabolism were quantified. Methyl jasmonate typically resulted in decreased growth and increased metabolite content in paclitaxel accumulating cultures. Conversely, elicitation typically resulted in either no change or decrease in accumulation of metabolites in the non-paclitaxel accumulating cultures. In both sets of cultures, variability was seen in the response to methyl jasmonate across generations of cell growth. Consolidation of these data determined that paclitaxel accumulation and basal levels of phenolic and flavonoid compounds are indirectly correlated with aggregate size. These approaches assess alternative metabolic pathways that are linked to paclitaxel biosynthesis and provide a comprehensive strategy to both understand the relationship between conserved and specialized metabolism in plants and in the design of strategies to increase natural product yields in plant cell culture.

9.
J Sci Med Sport ; 24(10): 1015-1020, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32540320

RESUMO

OBJECTIVES: The aim of this study was to investigate if and to what extent small lateral wedges inserted under the ski boot, known as canting, could impact knee kinematics/kinetics, balance, and neuromuscular activity in recreational alpine skiers in the laboratory setting. DESIGN: Experimental, crossover study with repeated-measures analysis METHODS: Thirty-eight recreational skiers completed a single-leg postural balance test while wearing standardized ski boots in their unmodified state (control), and with medial and lateral canting wedges applied. Kinematics, kinetics, postural control measures, and neuromuscular activity of the lower extremity were assessed using optical motion capture, instrumented force plates, and electromyography. RESULTS: Canting modifications had significant impact on lower extremity kinematics and kinetics: canting wedges on the medial side of the foot significantly decreased knee valgus moments, hip internal rotation, and hip adduction. Medial canting also improved some postural control measures associated with balance quality, and reduced activation levels of the Vastus Lateralis, Biceps Femoris, and Tibialis Anterior. CONCLUSIONS: In the laboratory setting, canting appears to be an appropriate option for improving balance in alpine skiers. Medial canting can alter skier kinematics and kinetics in ways which are consistent with mechanisms of ACL injury. Canting may also result in reduced neuromuscular effort. These changes in movement have potential to prevent lower limb injuries in alpine skiers. The findings of this study motivate future research to predict individual responses to canting treatment in a study setting more closely resembling the sports environment.


Assuntos
Acidentes por Quedas/prevenção & controle , Traumatismos em Atletas/prevenção & controle , Desenho de Equipamento , Músculo Esquelético/fisiologia , Equilíbrio Postural/fisiologia , Esqui , Equipamentos Esportivos , Adulto , Idoso , Fenômenos Biomecânicos , Estudos Cross-Over , Eletromiografia , Feminino , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-34716204

RESUMO

The methodologic approach used in next-generation sequencing (NGS) affords a high depth of coverage in genomic analysis. Inherent in the nature of genomic testing, there exists potential for identifying genomic findings that are incidental or secondary to the indication for clinical testing, with the frequency dependent on the breadth of analysis and the tissue sample under study. The interpretation and management of clinically meaningful incidental genomic findings is a pressing issue particularly in the pediatric population. Our study describes a 16-mo-old male who presented with profound global delays, brain abnormality, progressive microcephaly, and growth deficiency, as well as metopic craniosynostosis. Clinical exome sequencing (ES) trio analysis revealed the presence of two variants in the proband. The first was a de novo variant in the PPP2R1A gene (c.773G > A, p.Arg258His), which is associated with autosomal dominant (AD) intellectual disability, accounting for the proband's clinical phenotype. The second was a recurrent hotspot variant in the CBL gene (c.1111T > C, p.Tyr371His), which was present at a variant allele fraction of 11%, consistent with somatic variation in the peripheral blood sample. Germline pathogenic variants in CBL are associated with AD Noonan syndrome-like disorder with or without juvenile myelomonocytic leukemia. Molecular analyses using a different tissue source, buccal epithelial cells, suggest that the CBL alteration may represent a clonal population of cells restricted to leukocytes. This report highlights the laboratory methodologic and interpretative processes and clinical considerations in the setting of acquired variation detected during clinical ES in a pediatric patient.


Assuntos
Achados Incidentais , Deficiência Intelectual , Criança , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Fenótipo
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