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1.
J Interprof Care ; 29(4): 404-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25514214

RESUMO

Patients with self-limiting respiratory tract infections (RTIs) are frequently seen in general practice. Although antibiotics are ineffective for these conditions, they are often prescribed by general practitioners (GPs), and perceived patient expectations for an antibiotic plays an important role in the decision to prescribe one. Superfluous use of antibiotics contributes to antimicrobial resistance. High numbers of nurse prescribers work alongside GPs and these prescribers see education and self-management advice as central to the care of these patients. Multi-faceted interventions, designed to reduce antibiotic prescribing, only exist for GPs. Such interventions should foster interprofessional collaboration and, as such, consider the needs and experiences of the different prescribers, and the views of patients. This paper outlines a research study in which a questionnaire will be distributed to patients who consult with a nurse prescriber to see whether their expectations influence their satisfaction with the consultation outcome. Findings will guide the development of an interprofessional intervention designed to promote collaborative practice and appropriate and responsible antibiotic prescribing in primary care.


Assuntos
Antibacterianos/administração & dosagem , Relações Interprofissionais , Enfermeiras e Enfermeiros/organização & administração , Atenção Primária à Saúde , Infecções Respiratórias/tratamento farmacológico , Atitude do Pessoal de Saúde , Resistência Microbiana a Medicamentos , Satisfação do Paciente , Padrões de Prática Médica
2.
Curr Med Chem ; 29(35): 5615-5687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35894453

RESUMO

BACKGROUND: Oxytocin is a nonapeptide synthesized in the paraventricular and supraoptic nuclei of the hypothalamus. Historically, this molecule has been involved as a key factor in the formation of infant attachment, maternal behavior and pair bonding and, more generally, in linking social signals with cognition, behaviors and reward. In the last decades, the whole oxytocin system has gained a growing interest as it was proposed to be implicated in etiopathogenesis of several neurodevelopmental and neuropsychiatric disorders. METHODS: With the main goal of an in-depth understanding of the oxytocin role in the regulation of different functions and complex behaviors as well as its intriguing implications in different neuropsychiatric disorders, we performed a critical review of the current state of the art. We carried out this work through the PubMed database up to June 2021 with the search terms: 1) "oxytocin and neuropsychiatric disorders"; 2) "oxytocin and neurodevelopmental disorders"; 3) "oxytocin and anorexia"; 4) "oxytocin and eating disorders"; 5) "oxytocin and obsessive- compulsive disorder"; 6) "oxytocin and schizophrenia"; 7) "oxytocin and depression"; 8) "oxytocin and bipolar disorder"; 9) "oxytocin and psychosis"; 10) "oxytocin and anxiety"; 11) "oxytocin and personality disorder"; 12) "oxytocin and PTSD". RESULTS: Biological, genetic, and epigenetic studies highlighted quality and quantity modifications in the expression of oxytocin peptide or in oxytocin receptor isoforms. These alterations would seem to be correlated with a higher risk of presenting several neuropsychiatric disorders belonging to different psychopathological spectra. Collaterally, the exogenous oxytocin administration has shown to ameliorate many neuropsychiatric clinical conditions. CONCLUSION: Finally, we briefly analyzed the potential pharmacological use of oxytocin in a patient with severe symptomatic SARS-CoV-2 infection due to its anti-inflammatory, antioxidative and immunoregulatory properties.


Assuntos
Fármacos Antiobesidade , COVID-19 , Transtornos Mentais , Proteínas de Ligação a DNA , Feminino , Humanos , Lactente , Transtornos Mentais/tratamento farmacológico , Ocitocina/uso terapêutico , Psicotrópicos/farmacologia , Psicotrópicos/uso terapêutico , Receptores de Ocitocina , SARS-CoV-2
3.
ACS Mater Au ; 2(3): 330-342, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-36855386

RESUMO

Colloidal germanium (Ge) nanocrystals (NCs) are of great interest with possible applications for photovoltaics and near-IR detectors. In many examples of colloidal reactions, Ge(II) precursors are employed, and NCs of diameter ∼3-10 nm have been prepared. Herein, we employed a two-step microwave-assisted reduction of GeI4 in oleylamine (OAm) to prepare monodispersed Ge NCs with a size of 18.9 ± 1.84 nm. More importantly, the as-synthesized Ge NCs showed high crystallinity with single-crystal nature as indicated by powder X-ray diffraction, selected area electron diffraction, and high-resolution transmission electron microscopy. The Tauc plot derived from photothermal deflection spectroscopy measurement on Ge NCs thin films shows a decreased bandgap of the Ge NCs obtained from GeI4 compared with that of the Ge NCs from GeI2 with a similar particle size, indicating a higher crystallinity of the samples prepared with the two-step reaction from GeI4. The calculated Urbach energy indicates less disorder in the larger NCs. This disorder might correlate with the fraction of surface states associated with decreased particle size or with the increased molar ratio of ligands to germanium. Solutions involved in this two-step reaction were investigated with 1H NMR spectroscopy and high-resolution mass spectrometry (MS). One possible reaction pathway is proposed to unveil the details of the reaction involving GeI4 and OAm. Overall, this two-step synthesis produces high-quality Ge NCs and provides new insight on nanoparticle synthesis of covalently bonding semiconductors.

4.
Artigo em Inglês | MEDLINE | ID: mdl-34639416

RESUMO

There is a paucity of research exploring how relationships with household pets may impact maternal mental health. We are unaware of any study to date that has examined associations between individuals' relationships with their pets and psychological adjustment in the perinatal period. Using a biobehavioral lens, this paper provides a narrative overview of the literature on perinatal mental health and human-animal interaction (HAI). We focus on the role of social relationships, stress, and stress reduction in relation to perinatal mental health; the role of HAI in perceptions of social support, stressors, and stress reduction; and gaps in empirical knowledge concerning the role of HAI in perinatal mental health. Finally, we integrate contemporary biobehavioral models of perinatal mental health and HAI (i.e., Comprehensive Model of Mental Health during the Perinatal Period and the HAI-HPA Transactional Model) to propose a new conceptual framework that depicts ways in which HAI during the perinatal period may influence maternal and child health and wellbeing. To our knowledge, this is the first paper to consider the role of HAI in biobehavioral responses and mental health during the perinatal period. We conclude with recommendations for future research and improved perinatal care.


Assuntos
Interação Humano-Animal , Saúde Mental , Animais , Criança , Feminino , Humanos , Recém-Nascido , Parto , Assistência Perinatal , Gravidez , Apoio Social
5.
ACS Nano ; 15(1): 1685-1700, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33434437

RESUMO

Doped and alloyed germanium nanocrystals (Ge NCs) are potential candidates for a variety of applications such as photovoltaics and near IR detectors. Recently, bismuth (Bi) as an n-type group 15 element was shown to be successfully and kinetically doped into Ge NCs through a microwave-assisted solution-based synthesis, although Bi is thermodynamically insoluble in bulk crystalline Ge. To expand the composition manipulation of Ge NCs, another more common n-type group 15 element for semiconductors, antimony (Sb), is investigated. Oleylamine (OAm)- and OAm/trioctylphosphine (TOP)-capped Sb-doped Ge NCs have been synthesized by the microwave-assisted solution reaction of GeI2 with SbI3. Passivating the Ge surface with a binary ligand system of OAm/TOP results in formation of consistently larger NCs compared to OAm alone. The TOP coordination on the Ge surface is confirmed by 31P NMR and SEM-EDS. The lattice parameter of Ge NCs increases with increasing Sb concentration (0.00-2.0 mol %), consistent with incorporation of Sb. An increase in the NC diameter with higher content of SbI3 in the reaction is shown by TEM. XPS and EDS confirm the presence of Sb before and after removal of surface ligands with hydrazine and recapping the Ge NC surface with dodecanethiol (DDT). EXAFS analysis suggests that Sb resides within the NCs on highly distorted sites next to a Ge vacancy as well as on the crystallite surface. High Urbach energies obtained from photothermal deflection spectroscopy (PDS) of the films prepared from pristine Ge NC and Sb-doped Ge NCs indicate high levels of disorder, in agreement with EXAFS data. Electrical measurements on TiO2-NC electron- and hole-only devices show an increase in hole conduction, suggesting that the Sb-vacancy defects are behaving as a p-type dopant in the Ge NCs, consistent with the vacancy model derived from the EXAFS results.

7.
Sci Rep ; 6: 25814, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27174617

RESUMO

We aimed to evaluate the association of cadmium exposure with the risk of prostate cancer in both the general and occupational populations. Online database searches were performed for studies of prostate cancer risk and cadmium exposure. Twelve cohort studies (5 in the general, 7 in occupational populations) and 9 case-control studies (3 in the general, 6 in occupational populations) were identified. Five/seven cohort studies in the general and occupational populations consist of 78,263/13, 434 participants with a mean follow-up of 12.1/43.0 years, respectively. Case-control studies include 334 cases/670 controls in the general population, and 1,315 cases/4,477 controls in occupational populations. Comparing the highest to the lowest category of cadmium exposure in the general population, the weighted relative risk of prostate cancer incidence and mortality among cohort studies, and the weighted odds ratio in case-control studies were 1.05 (95%CI [0.91, 1.22]), 0.83 (95%CI [0.35, 1.98]), and 1.27 (95%CI [0.58,2.78]), respectively. For occupational populations, the weighted OR in case-control studies was 1.17 (95%CI [0.85, 1.62]), and the weighted standardized mortality ratio in cohort studies was 98 (95%CI [75, 126]). Accumulated epidemiological evidence does not support the hypothesis that cadmium exposure may increase the risk of prostate cancer in either the general or occupational populations.


Assuntos
Cádmio/efeitos adversos , Exposição Ambiental/análise , Exposição Ocupacional/análise , Neoplasias da Próstata/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Intervalos de Confiança , Humanos , Masculino , Análise Multivariada , Razão de Chances , Risco , Fatores de Risco
8.
Amyloid ; 10(2): 97-109, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12964417

RESUMO

In an attempt to understand the mechanism of amyloid fibril formation in light chain amyloidosis, the properties of amyloidogenic (SMA) and benign (LEN) immunoglobulin light chain variable domains (VL) were compared. The conformations of LEN and SMA were measured using secondary and tertiary structural probes over the pH range from 2 and 8. At all pH values, LEN was more stable than SMA. The CD spectra of LEN at pH 2 were comparable to those of SMA at pH 7.5, indicating that the low pH conformation of LEN closely resembles that of SMA at physiological pH. At low pH, a relatively unfolded intermediate conformation is populated for SMA and rapidly leads to amyloid fibrils. The lack of such an intermediate with LEN, is attributed to sequence differences and accounts for the lack of LEN fibrils in the absence of agitation. A kappa IV-specific monoclonal antibody that recognizes the N-terminal of SMA caused unraveling of the fibrils to the protofilaments and was observed to bind to one end of SMA protofilaments by atomic force microscopy. The antibody result indicates that each protofilament is asymmetric with different ends. A model for the formation of fibrils by SMA is proposed.


Assuntos
Amiloide/química , Amiloidose/metabolismo , Anticorpos Monoclonais/química , Cadeias Leves de Imunoglobulina/química , Amiloide/imunologia , Amiloide/metabolismo , Amiloidose/imunologia , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Sítios de Ligação de Anticorpos/imunologia , Dicroísmo Circular , Humanos , Concentração de Íons de Hidrogênio , Cadeias Leves de Imunoglobulina/imunologia , Cadeias Leves de Imunoglobulina/metabolismo , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/imunologia , Região Variável de Imunoglobulina/metabolismo , Cinética , Microscopia de Força Atômica , Modelos Químicos , Modelos Moleculares , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Am J Primatol ; 25(3): 191-201, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-31948181

RESUMO

The present report documents the breeding success of a new colony of common marmosets (Callithrix jacchus jacchus) and demonstrates a correlation between environmental stress and reproductive success. Environmental conditions ranged chronologically over 40 months, through four periods: I) the initial period, when the colony was formed; II) a phase of relative environmental stability; III) a stage of "environmental stress" (when the colony was disrupted by nearby construction); and IV) a return to a stable environment. Examination of reproductive status during each period indicated that the colony exhibited severe reproductive suppression during the time of the environmental disruption. Parity and the number of live births decreased and the number of spontaneous abortions increased during this period. Reproductive success remained low during period IV. More triplets than twins were born during the period of relative environmental stability.

10.
Nanotechnology ; 23(40): 405401, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-22997175

RESUMO

We report on photovoltaic cells based on ternary PbS(0.9)Se(0.1) quantum dots utilizing a heterojunction type device configuration. The best device shows an AM 1.5 power conversion efficiency of 4.25%. Furthermore, this ternary PbS(x)Se(1-x) quantum dot heterojunction device has a peak external quantum efficiency above 100% at 2.76 eV, approximately 2.7× the bandgap energy. The ternary quantum dots combine the higher short circuit currents of the binary PbSe system with the higher open circuit voltages of the binary PbS system.

11.
J Phys Condens Matter ; 22(5): 055301, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21386338

RESUMO

We report detailed degradation and rejuvenation studies of AC electroluminescence (EL) of the phosphor ZnS:Cu,Cl, aiming to better understand the physical mechanisms that control EL emission. We find that the AC EL emission spectra vary considerably with the AC driving frequency but all spectra can be fit to a sum of four Gaussians. During degradation, although there is a large overall decrease in amplitude, the shape of the emission spectra measured at a given AC frequency does not change. Annealing the samples after they are significantly degraded can rejuvenate the phosphors with a maximum rejuvenation occurring (for fixed annealing times) near 180 °C. Further, these test cells can be degraded and rejuvenated multiple times. However studies at slightly higher annealing temperatures (240 °C) show significant thermal degradation and, perhaps more importantly, a change in the spectral shape; this likely indicates that two distinct mechanisms are then operative. In extended x-ray absorption fine structure (EXAFS) experiments we find that the CuS nanoprecipitates in the ZnS host (∼ 75% of the Cu is in the CuS precipitates) do not change significantly after the 240 °C anneal; these experiments also provide a more detailed comparison of the local structure about Cu in pure CuS, and in ZnS:Cu,Cl. In addition, the EXAFS experiments also place an upper limit on the fraction of possible interstitial Cu sites, proposed as a blue emission center, at less than 10%. The combined experiments place strong constraints on the mechanisms for degradation and rejuvenation and suggest that EL degradation is most likely caused by either Cu or Cl diffusion under high E-fields, while thermal diffusion at slightly elevated temperatures without E-fields present, re-randomizes the (isolated) dopant distributions. Higher T anneals appear to damage the sharp tips on the precipitates.

12.
J Chem Phys ; 124(20): 204709, 2006 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-16774366

RESUMO

The ion-mediated conduction and versatility of device fabrication of conducting polymers provide a route to the study of neural signaling. Patterned junctions of conducting polypyrrole have been electropolymerized on commercially available microelectrode arrays, with typical dimensions 200 mum between electrodes, each electrode being 30 mum in diameter. Tetrabutylammonium perchlorate or sodium p-toluenesulfonate were used as electrolyte/counterion in the organic solvent. Individual polypyrrole junctions, when synthesized and connected in a three-electrode configuration, exhibit current-switching behavior analogous to neural weighting. Junctions copolymerized with thiophene exhibit current rectification and the nonlinear current-voltage behavior requisite for complex neural systems (i.e., the activation function).

13.
Prev Med ; 41(2): 399-405, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15890396

RESUMO

BACKGROUND: Despite early detection having been identified as a key factor in long-term survival of patients with breast cancer, women with locally advanced breast cancer continued to present at many medical centers. METHODS: Women with locally advanced breast cancer (LABC) (N = 11) and matched controls (N = 11) with Stage I or II breast cancer completed semi-structured interviews and the Hospital Anxiety and Depression Scale, Life Orientation Test, Multidimensional Health Locus of Control Scale, Body Investment Scale, Monitor-Blunter Style Scale, and Religious Coping Scale. Five spouses of the LABC group and eight control partners were similarly assessed. RESULTS: On psychological tests, no significant differences were found between patient groups; however, LABC spouses reported significantly greater active religious surrender (t = 2.37, P = 0.037) and depression (t = 3.54, P = 0.047) than control spouses. The women's semi-structured interviews identified that LABC was associated with inattention to routine breast cancer screening, denial, fatalism and reliance on alternative therapies. Spouses of the LABC group tended to be more passive in their wives' medical care, and also utilized fatalistic thinking and denial. CONCLUSIONS: It is important for health care providers to identify patients who will require extra encouragement to seek timely medical care and to follow through with treatment recommendations.


Assuntos
Neoplasias da Mama/psicologia , Negação em Psicologia , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Cônjuges/psicologia
14.
J Struct Biol ; 151(3): 229-38, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16125973

RESUMO

Thioflavin T is a benzothiazole dye that exhibits enhanced fluorescence upon binding to amyloid fibrils and is commonly used to diagnose amyloid fibrils, both ex vivo and in vitro. In aqueous solutions, thioflavin T was found to exist as micelles at concentrations commonly used to monitor fibrils by fluorescence assay ( approximately 10-20 microM). Specific conductivity changes were measured at varying concentration of thioflavin T and the critical micellar concentration was calculated to be 4.0+/-0.5 microM. Interestingly, changes in the fluorescence excitation and emission of thioflavin T were also dependent on the micelle formation. The thioflavin T micelles of 3 nm diameter were directly visualized using atomic force microscopy, and bound thioflavin T micelles were observed along the fibril length for representative fibrils. Increasing concentration of thioflavin T above the critical micellar concentration shows increased numbers of micelles bound along the length of the amyloid fibrils. Thioflavin T micelles were disrupted at low pH as observed by atomic force microscopy and fluorescence enhancement upon binding of thioflavin T to amyloid fibrils also reduced by several-fold upon decreasing the pH to below 3. This suggests that positive charge on the thioflavin T molecule has a role in its micelle formation that then bind the amyloid fibrils. Our data suggests that the micelles of thioflavin T bind amyloid fibrils leading to enhancement of fluorescence emission.


Assuntos
Amiloide/metabolismo , Tiazóis/metabolismo , Benzotiazóis , Sítios de Ligação , Deutério , Fluorescência , Polarização de Fluorescência , Corantes Fluorescentes/química , Concentração de Íons de Hidrogênio , Micelas , Microscopia de Força Atômica , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Tiazóis/química , Água/química
15.
J Biol Chem ; 279(23): 24452-9, 2004 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-15056656

RESUMO

Amyloidoses and related protein deposition diseases involve the transformation of normally soluble proteins into insoluble deposits, usually fibrillar in nature. Although it was originally assumed that the fibrils were the toxic species, this assumption has recently been called into question. Accumulating evidence in several systems suggests that oligomeric intermediates on the aggregation pathway may be toxic. In the present study we used in situ atomic force microscopy to monitor aggregation in aqueous solution in real time. The sample used was an amyloidogenic immunoglobulin light chain, involved in AL or light chain amyloidosis. The nature of the observed oligomeric intermediates was dependent on the conditions of incubation, especially pH and ionic strength. Several different aggregation intermediates with a variety of morphologies, including annular or torus-shaped species, were observed. The data indicate that protein aggregation can be very complex, involving a variety of different oligomeric intermediates whose population will be determined by the kinetic and thermodynamic competition between them.


Assuntos
Amiloide/química , Microscopia de Força Atômica/métodos , Silicatos de Alumínio/química , Benzotiazóis , Concentração de Íons de Hidrogênio , Íons , Cinética , Estrutura Terciária de Proteína , Cloreto de Sódio/farmacologia , Temperatura , Termodinâmica , Tiazóis/química , Fatores de Tempo
16.
J Biol Chem ; 277(52): 50914-22, 2002 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-12356747

RESUMO

Light chain (or AL) amyloidosis is characterized by the pathological deposition of insoluble fibrils of immunoglobulin light chain fragments in various tissues, walls of blood vessels, and basement membranes. In the present investigation, the in vitro assembly of a recombinant amyloidogenic light chain variable domain, SMA, on various surfaces was monitored using atomic force microscopy. SMA formed fibrils on native mica at pH 5.0, conditions under which predominantly amorphous aggregates form in solution. Fibril formation was accelerated significantly on surfaces compared with solution; for example, fibrils grew on surfaces at significantly faster rates and at much lower concentrations than in solution. No fibrils were observed on hydrophobic or positively charged surfaces or at pH >7.0. Two novel types of fibril growth were observed on the surface: bidirectional linear assembly of oligomeric units, and linear growth from preformed amorphous cores. In addition to catalyzing the rate of fibrillation, the mechanism of fibril formation on the surfaces was significantly different from in solution, but it may be more physiologically relevant because in vivo the deposits are associated with surfaces.


Assuntos
Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/ultraestrutura , Amiloidose/patologia , Membrana Basal/patologia , Humanos , Cadeias Leves de Imunoglobulina/sangue , Cinética , Microfibrilas/química , Microfibrilas/ultraestrutura , Microscopia de Força Atômica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
17.
Biophys J ; 85(2): 1135-44, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12885658

RESUMO

Based on atomic force microscopy analysis of the morphology of fibrillar species formed during fibrillation of alpha-synuclein, insulin, and the B1 domain of protein G, a previously described model for the assembly of amyloid fibrils of immunoglobulin light-chain variable domains is proposed as a general model for the assembly of protein fibrils. For all of the proteins studied, we observed two or three fibrillar species that vary in diameter. The smallest, protofilaments, have a uniform height, whereas the larger species, protofibrils and fibrils, have morphologies that are indicative of multiple protofilaments intertwining. In all cases, protofilaments intertwine to form protofibrils, and protofibrils intertwine to form fibrils. We propose that the hierarchical assembly model describes a general mechanism of assembly for all amyloid fibrils.


Assuntos
Amiloide/ultraestrutura , Cristalografia/métodos , Imunoglobulina G/ultraestrutura , Insulina/química , Microscopia de Força Atômica/métodos , Modelos Moleculares , Proteínas do Tecido Nervoso/ultraestrutura , Amiloide/química , Sítios de Ligação , Dimerização , Imunoglobulina G/química , Modelos Químicos , Proteínas do Tecido Nervoso/química , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Sinucleínas , alfa-Sinucleína
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