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1.
J Neurosci ; 44(2)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37968116

RESUMO

Reversal learning measures the ability to form flexible associations between choice outcomes with stimuli and actions that precede them. This type of learning is thought to rely on several cortical and subcortical areas, including the highly interconnected orbitofrontal cortex (OFC) and basolateral amygdala (BLA), and is often impaired in various neuropsychiatric and substance use disorders. However, the unique contributions of these regions to stimulus- and action-based reversal learning have not been systematically compared using a chemogenetic approach particularly before and after the first reversal that introduces new uncertainty. Here, we examined the roles of ventrolateral OFC (vlOFC) and BLA during reversal learning. Male and female rats were prepared with inhibitory designer receptors exclusively activated by designer drugs targeting projection neurons in these regions and tested on a series of deterministic and probabilistic reversals during which they learned about stimulus identity or side (left or right) associated with different reward probabilities. Using a counterbalanced within-subject design, we inhibited these regions prior to reversal sessions. We assessed initial and pre-/post-reversal changes in performance to measure learning and adjustments to reversals, respectively. We found that inhibition of the ventrolateral orbitofrontal cortex (vlOFC), but not BLA, eliminated adjustments to stimulus-based reversals. Inhibition of BLA, but not vlOFC, selectively impaired action-based probabilistic reversal learning, leaving deterministic reversal learning intact. vlOFC exhibited a sex-dependent role in early adjustment to action-based reversals, but not in overall learning. These results reveal dissociable roles for BLA and vlOFC in flexible learning and highlight a more crucial role for BLA in learning meaningful changes in the reward environment.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Ratos , Masculino , Feminino , Animais , Incerteza , Complexo Nuclear Basolateral da Amígdala/fisiologia , Ratos Long-Evans , Córtex Pré-Frontal/fisiologia , Reversão de Aprendizagem/fisiologia
2.
J Intellect Disabil Res ; 67(2): 148-158, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36573033

RESUMO

BACKGROUND: The factor structure of the Behavior Rating Inventory of Executive Function, second edition (BRIEF2) has been widely examined in both typically developing children and specific clinical samples. Despite the frequent use of the BRIEF2 for measuring executive functioning in individuals with Down syndrome, no study has investigated the factorial validity or dimensionality of the BRIEF2 in this population. This study aimed to address this notable gap in the literature. METHODS: Parents of 407 children and youth with Down syndrome aged 6-18 years completed the BRIEF2 as part of different studies led by six sites. Three competing models proposed by previous studies were analysed using Confirmatory Factor Analysis: the theoretical structure of the BRIEF2 where the scales were constrained to load on three factors labelled as Cognitive, Behavioral, and Emotional Regulation, a two-factor correlated model with the merged Behavioral and Emotional regulation, and a single-factor model. RESULTS: The three-factor model provided a better fit than the one- and two-factor models, yet a large correlation was observed between Behavioural and Emotional regulation factors. The results provide meaningful explanatory value for the theoretical structure of the BRIEF2. However, the Behavioral and Emotional regulation factors might be less differentiated and the two-factor structure of the BRIEF2 may also make theoretical and empirical sense. CONCLUSIONS: Although more studies are needed to further examine the factor structure of the BRIEF2 in youth with Down syndrome, this investigation provides preliminary support for the interpretation of the three executive function index scores provided by the BRIEF2: Cognitive, Behavioral, and Emotional Regulation.


Assuntos
Síndrome de Down , Criança , Humanos , Adolescente , Função Executiva/fisiologia , Análise Fatorial , Pais/psicologia , Psicometria
3.
J Intellect Disabil Res ; 67(8): 753-769, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37218393

RESUMO

BACKGROUND: Inhibitory control measures have been commonly used when assessing individuals with Down syndrome. However, minimal attention has been devoted to evaluating the appropriateness of specific assessments for use in this population, potentially leading to erroneous conclusions. This study aimed to examine the psychometric properties of measures of inhibitory control among youth with Down syndrome. We sought to examine the feasibility, presence of floor or practice effects, test-retest reliability, convergent validity and correlations with broader developmental domains of a set of inhibitory control tasks. METHODS: A sample of 97 youth with Down syndrome aged 6 to 17 years old participated in verbal and visuospatial tasks of inhibitory control including the Cat/dog Stroop, Neuropsychological Assessment Second Edition (NEPSY-II) Statue, National Institutes of Health (NIH) Toolbox Cognition Battery (TCB) Flanker, Leiter-3 Attention Sustained, and the Test of Attentional Performance for Children (KiTAP) Go/No-go and Distractibility subtests. Youth also completed standardised assessments of cognition and language, and caregivers completed rating scales. Psychometric properties on the tasks of inhibitory control were evaluated against a priori criteria. RESULTS: Apart from demonstrating negligible practice effects, adequate psychometric properties were not observed for any inhibitory control measure within the current sample's age range. One task with low working memory demands (NEPSY-II Statue) generally had better psychometric properties than the other tasks assessed. Subgroups of participants with an IQ greater than 30 and age more than 8 years were shown to be more likely to be able to complete the inhibition tasks. CONCLUSIONS: Findings suggest better feasibility for analogue tasks rather than computerised assessments of inhibitory control. Given the weak psychometrics of several common measures, future studies are required to evaluate other inhibitory control measures, specifically those with reduced working memory demands for youth with Down syndrome. Recommendations for use of the inhibitory control tasks among youth with Down syndrome are provided.


Assuntos
Síndrome de Down , Humanos , Adolescente , Animais , Cães , Psicometria , Síndrome de Down/psicologia , Reprodutibilidade dos Testes , Testes Neuropsicológicos , Cognição/fisiologia
4.
Osteoporos Int ; 32(12): 2407-2431, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34309694

RESUMO

Due to the metabolic nature of osteoporosis, this study was conducted to identify metabolomic studies investigating the metabolic profile of low bone mineral density (BMD) and osteoporosis. A comprehensive systematic literature search was conducted through PubMed, Web of Science, Scopus, and Embase databases up to April 08, 2020, to identify observational studies with cross-sectional or case-control designs investigating the metabolic profile of low BMD in adults using biofluid specimen via metabolomic platform. The quality assessment panel specified for the "omics"-based diagnostic research (QUADOMICS) tool was used to estimate the methodologic quality of the included studies. Ten untargeted and one targeted approach metabolomic studies investigating biomarkers in different biofluids through mass spectrometry or nuclear magnetic resonance platforms were included in the systematic review. Some metabolite panels, rather than individual metabolites, showed promising results in differentiating low BMD from normal. Candidate metabolites were of different categories including amino acids, followed by lipids and carbohydrates. Besides, certain pathways were suggested by some of the studies to be involved. This systematic review suggested that metabolic profiling could improve the diagnosis of low BMD. Despite valuable findings attained from each of these studies, there was great heterogeneity regarding the ethnicity and age of participants, samples, and the metabolomic platform. Further longitudinal studies are needed to validate the results and confirm the predictive role of metabolic profile on low BMD and fracture. It is also mandatory to address and minimize the heterogeneity in future studies by using reliable quantitative methods. Summary: Due to the metabolic nature of osteoporosis, researchers have considered metabolomic studies recently. This systematic review showed that metabolic profiling including different categories of metabolites could improve the diagnosis of low BMD. However, great heterogeneity was observed and it is mandatory to address and minimize the heterogeneity in future studies.


Assuntos
Densidade Óssea , Doenças Ósseas Metabólicas , Adulto , Biomarcadores , Estudos Transversais , Humanos , Metabolômica
5.
Nanotechnology ; 27(3): 035203, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26650565

RESUMO

This study examines the sintering of inkjet printed nanoparticle copper ink in a room environment using a laser as a high speed sintering method. Printed patterns were sintered with increasing laser scanning speed up to 400 mm s(-1). The resistivities of the sintered structures were measured and plotted against the scanning speeds. Increased resistivity seems to correlate with increased scanning speed. A selections of analytical methods was used to study the differences in microstructure and composition of the sintered structures. Based on the results, no discernable difference in the microstructure was noticed between the structures sintered using 20 mm s(-1) to 400 mm s(-1) scanning speeds; only the structure scanned using 5 mm s(-1) speed showed a vastly different microstructure and no resistivity was measurable on this structure. Compositional studies revealed that, apart from the structure scanned with 5 mm s(-1) speed which contained the highest oxygen, the rest of the structures showed a steady oxygen increase with increased scanning speed.

6.
Appl Opt ; 54(10): 2606-14, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25967165

RESUMO

In this paper, our aim is to control optical bistability (OB) and optical multistability (OM) in a five-level system designed in a double quantum dot (QD) nanostructure. In a realistic example, this atomic system is created in two semiconductor QDs (In(x)Ga(1-x)N/GaN), owning transfer of carriers via tunneling effect. OB behavior is controlled not only by the inter-dot tunneling effect but also by variation of probe detuning and intensity of the control field. It is demonstrated that voltage-controlled detuning can significantly affect the behavior of OB and OM; therefore, the OM converts to OB by probe detuning and intensity of the control field.

7.
Intern Med J ; 45(9): 925-33, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26010582

RESUMO

BACKGROUND AND AIM: To determine predictors of short- and long-term outcomes in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD) (AECOPD) presenting to hospital. METHODS: A prospective clinical audit of AECOPD attendances to the only public acute general hospital in Southern Tasmania, Australia. Out of 416 attendances with AECOPD to the emergency department (ED) between November 2006 and July 2008, 150 patients with 218 attendances were followed to March 2009. Predictors of hospital admission from ED, in-hospital death, length of hospital stay, post-discharge mortality and re-attendance rate for AECOPD were the main outcomes. RESULTS: There were no clear differences between patients admitted to hospital and those sent home from ED. Predictors of in-hospital death were initial physiologic parameters, that is, arterial pH, PaCO2 , oxygen saturation and blood pressure. Longer hospital stay was associated with older age, current smoking, hyperglycaemia, lower blood pressure and lower oxygen saturation. Risk of mortality after discharge was associated with a history of myocardial infarction, nursing home residence and severity of COPD. Re-attendance rate was associated with osteoporosis, younger age and severity of COPD. CONCLUSIONS: Further investigation into the process of decision making about which AECOPD patients are admitted from the ED is required. Short-term outcomes, in-hospital death and length of hospital stay are mainly predicted by severity of the acute exacerbation and patient demographics. Although severity of COPD was a predictor of long-term outcomes, the main predictors of these were presence of co-morbidities.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Mortalidade Hospitalar/tendências , Doença Pulmonar Obstrutiva Crônica/mortalidade , Idoso de 80 Anos ou mais , Auditoria Clínica , Comorbidade , Técnicas de Apoio para a Decisão , Progressão da Doença , Feminino , Hospitalização , Humanos , Masculino , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Tasmânia/epidemiologia
8.
Andrologia ; 46(7): 726-30, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23869800

RESUMO

Almost all testicular germ cell tumours are proved to originate from carcinoma in situ cells. Infertility is one of the factors that increase the risk of carcinoma in situ. The reported prevalence for carcinoma in situ from different parts of the world is 0-3.7% in infertile men. This retrospective study was performed to determine the prevalence of carcinoma in situ in Iranian infertile men. We reviewed the testicular biopsies of 1153 infertile men at the pathology department of Avicenna Infertility Center. One hundred and fifty-one cases were suspicious of having carcinoma in situ. Immunohistochemical marker for placental alkaline phosphatase was employed to confirm the diagnosis of carcinoma in situ. Positive results were detected in 7 (0.6%) of 1153 cases (95% CI 0.24%-1.24%), 6 (0.94%) of which (95% CI 0.34%-2.04%) were under the age of 35 years (636 patients were in this age group). This study is the first study in Iran determining the prevalence of carcinoma in situ among the infertile Iranian men; the result is in the range of reports from other countries.


Assuntos
Carcinoma in Situ/epidemiologia , Infertilidade Masculina/complicações , Neoplasias Testiculares/epidemiologia , Adulto , Biópsia , Carcinoma in Situ/complicações , Carcinoma in Situ/patologia , Humanos , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Neoplasias Testiculares/complicações , Neoplasias Testiculares/patologia , Adulto Jovem
9.
J Wound Care ; 22(1): 22-3, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23299354

RESUMO

Calcinosis cutis is a cutaneous disorder characterised by abnormal deposition of calcium in the dermis. Treatment of this condition has variable success rates and includes medical, topical and surgical management. Here we describe a case of a woman with a painful calcinosis lesion on the buttocks, treated with excision and application of a bovine collagen-elastin dermal regeneration template, a thin, porous membrane consisting of a native bovine type I, II and V collagen-fibre template coated with elastin hydrolysate. The patient's wound healed without complication and without the use of a skin graft. She remains recurrence free at 10-month follow up, with satisfactory outcome.


Assuntos
Derme Acelular , Calcinose/cirurgia , Colágeno/uso terapêutico , Elastina/uso terapêutico , Escleroderma Sistêmico/cirurgia , Nádegas , Calcinose/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Escleroderma Sistêmico/patologia
10.
East Mediterr Health J ; 18(10): 1042-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23301359

RESUMO

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes (86% and 78% reduction respectively 2 weeks after treatment). There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries.


Assuntos
Anopheles/fisiologia , Insetos Vetores/fisiologia , Malária/prevenção & controle , Controle de Mosquitos/métodos , Poliestirenos/química , Animais , Anopheles/parasitologia , Insetos Vetores/parasitologia , Irã (Geográfico) , Larva
11.
J Mol Model ; 28(6): 141, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35536376

RESUMO

In this work, the density functional theory is used to study the local reactivity of cephalexin (CLX) to radical attack and explain the mechanism of the reaction between CLX and hydroxyl radical attack leading to degradation byproducts. The reaction between •OH and CLX is supposed to lead to either an addition of a hydroxyl radical or an abstraction of a hydrogen. The results showed that the affinity of cephalexin for addition reactions increases as it passes from the gas to the aqueous phase and decreases as it passes from the neutral to the ionized form. Thermodynamic data confirmed that OH addition radicals (Radd) are thermodynamically favored over H abstraction radicals (Rabs). The ecotoxicity assessments of CLX and its byproducts are estimated from the acute toxicities toward green algae, Daphnia, and fish. The formation of byproducts is safe for aquatic organisms, and only one byproduct is harmful to Daphnia.


Assuntos
Cefalexina , Radical Hidroxila , Animais , Cinética , Oxirredução , Água
12.
Artigo em Inglês | MEDLINE | ID: mdl-34506286

RESUMO

Walking/gait speed is a key measure for daily mobility characterization. To date, various studies have attempted to design algorithms to estimate walking speed using an inertial sensor worn on the lower back, which is considered as a proper location for activity monitoring in daily life. However, these algorithms were rarely compared and validated on the same datasets, including people with different preferred walking speed. This study implemented several original, improved, and new algorithms for estimating cadence, step length and eventually speed. We designed comprehensive cross-validation to compare the algorithms for walking slow, normal, fast, and using walking aids. We used two datasets, including reference data for algorithm validation from an instrumented mat (40 subjects) and shanks-worn inertial sensors (88 subjects), with normal and impaired walking patterns. The results showed up to 50% performance improvements. Training of algorithms on data from people with different preferred speeds led to better performance. For the slow walkers, an average RMSE of 2.5 steps/min, 0.04 m, and 0.10 m/s were respectively achieved for cadence, step length, and speed estimation. For normal walkers, the errors were 3.5 steps/min, 0.08 m, and 0.12 m/s. An average RMSE of 1.3 steps/min, 0.05 m, and 0.10 m/s were also observed on fast walkers. For people using walking aids, the error significantly increased up to an RMSE of 14 steps/min, 0.18 m, and 0.27 m/s. The results demonstrated the robustness of the proposed combined speed estimation approach for different speed ranges. It achieved an RMSE of 0.10, 0.18, 0.15, and 0.32 m/s for slow, normal, fast, and using walking aids, respectively.


Assuntos
Marcha , Velocidade de Caminhada , Algoritmos , Humanos , Perna (Membro) , Caminhada
13.
Plant Biol (Stuttg) ; 22(4): 647-654, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32215992

RESUMO

Agricultural burning is used in farm management operations; however, information about the impact of fire cues on the release and/or induction of secondary dormancy in crop seeds is scarce. Seeds from two oilseed rape cultivars were induced for high (HD) or low (LD) secondary dormancy using polyethyleneglycol (PEG) pre-treatment, and their germination after exposure to various fire cues was compared to control PEG pre-treated and non-dormant seeds. Non-dormant seed germination was unaffected by various fire cues. Low doses of aerosol smoke released secondary dormancy in HD seeds, while higher doses increased dormancy of LD seeds. Dilute smoke water also released HD seed secondary dormancy, but concentrated smke water enhanced dormancy in both LD and HD seeds. The concentrated aqueous extracts from charred oilseed rape straw only promoted germination of HD seeds, while dilution inhibited LD seed germination. Heat shock (80 °C, 5 min) released secondary dormancy in HD seeds; however, higher temperatures and/or increased exposure time was associated with seed death. GC-MS analyses of smoke water revealed two butenolides and an array of monoaromatic hydroxybenzene compounds with potential germination inhibitor or promoter activity. The extent of secondary dormancy induction in seeds affects their subsequent responses to fire cues. Both aerosol smoke and smoke water have both germination promoter and inhibitor activity. Lacking any butenolides, aqueous extracts of charred straw contain a potential germination stimulating steroid, i.e. ergosterol. The significance of fire-derived cues on behaviour of oilseed rape seeds in the soil seed bank is discussed.


Assuntos
Brassica napus , Incêndios , Germinação , Dormência de Plantas , Sementes , Brassica napus/fisiologia , Sinais (Psicologia) , Germinação/fisiologia , Sementes/fisiologia
14.
Comput Methods Biomech Biomed Engin ; 23(3): 103-113, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31847587

RESUMO

Digital Image Correlation (DIC) was used for studying the anisotropic behavior of the thin walled right ventricle of the human heart. Strains measured with Speckle Tracking Echocardiography (STE) were compared with the DIC data. Both DIC and STE were used to measure longitudinal strains of the right ventricle in the beginning of an open-heart surgery as well as after the cardiopulmonary bypass. Based on the results, the maximum end-systolic strains obtained with the DIC and STE change similarly during the surgery with less than 10% difference. The difference is largely due to the errors in matching the longitudinal direction in the two methods, sensitivity of the measurement to the positioning of the virtual extensometer of in both STE and DIC, and physiological difference of the measurements as the DIC measures the top surface of the heart whereas the STE obtains the data from below. The anisotropy of the RV was measured using full field principal strains acquired from the DIC displacement fields. The full field principal strains cover the entire region of interest instead of just two points as the virtual extensometer approach used by the STE. The principal strains are not direction dependent measures, and therefore are more independent of the anatomy of the patient and the exact positioning of the virtual strain gage or the STE probe. The results show that the longitudinal strains alone are not enough to fully characterize the behavior of the heart, as the deformation of the heart can be very anisotropic, and the anisotropy changes during the surgery, and from patient to patient.


Assuntos
Ventrículos do Coração/patologia , Ventrículos do Coração/cirurgia , Anisotropia , Diástole , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador , Miocárdio/patologia , Reprodutibilidade dos Testes , Estresse Mecânico
15.
J Dairy Sci ; 92(7): 3299-305, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19528607

RESUMO

Our objective was to compare the effects of grinding versus steam-rolling of barley grain at 30 or 35% of diet dry matter on feed intake, chewing behavior, rumen fermentation, and milk production in high-producing lactating cows. Eight multiparous Holstein cows (85 +/- 9 d in milk) were used in a replicated 4 x 4 Latin square design experiment with four 21-d periods. Each period included 14 d of adaptation and 7 d of sampling. Treatments included grinding (GB) or steam-rolling (SB) of barley grains at either 35 or 30% of dietary dry matter. Diets were prepared as a total mixed ration and delivered twice daily at 0730 and 1600 h. Neither processing method nor dietary barley grain inclusion rate affected dry matter intake, daily eating, ruminating and chewing times, rumen pH and major volatile fatty acid molar percentages, or milk percentages and yields of fat and protein. Energy-corrected milk yield increased for SB compared with GB at 35% but not at 30% barley grain. Feed efficiency was increased by SB, but was unaffected by dietary barley grain level. Results suggest that at 30% dietary barley grain, GB resulted in similar lactation performance as SB and that SB did not affect productivity when dietary barley grain increased from 30 to 35%. Regardless of barley grain level, grinding effectively maintained dry matter intake and rumen pH at 4 h postfeeding, whereas steam-rolling increased feed efficiency. Increasing barley grain from 30 to 35% of diet dry matter did not improve feed intake and milk production.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Manipulação de Alimentos/métodos , Hordeum/fisiologia , Lactação/fisiologia , Ração Animal/normas , Animais , Ingestão de Alimentos/fisiologia , Comportamento Alimentar/fisiologia , Feminino , Fermentação/fisiologia , Mastigação/fisiologia , Leite/química , Leite/metabolismo , Rúmen/metabolismo
16.
Nat Commun ; 10(1): 4704, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31624264

RESUMO

The subjective sense of certainty, or confidence, in ambiguous sensory cues can alter the interpretation of reward feedback and facilitate learning. We trained rats to report the orientation of ambiguous visual stimuli according to a spatial stimulus-response rule that must be learned. Following choice, rats could wait a self-timed delay for reward or initiate a new trial. Waiting times increase with discrimination accuracy, demonstrating that this measure can be used as a proxy for confidence. Chemogenetic silencing of BLA shortens waiting times overall whereas ACC inhibition renders waiting times insensitive to confidence-modulating attributes of visual stimuli, suggesting contribution of ACC but not BLA to confidence computations. Subsequent reversal learning is enhanced by confidence. Both ACC and BLA inhibition block this enhancement but via differential adjustments in learning strategies and consistent use of learned rules. Altogether, we demonstrate dissociable roles for ACC and BLA in transmitting confidence and learning under uncertainty.


Assuntos
Complexo Nuclear Basolateral da Amígdala/fisiologia , Comportamento de Escolha/fisiologia , Giro do Cíngulo/fisiologia , Reversão de Aprendizagem/fisiologia , Incerteza , Animais , Condicionamento Operante/fisiologia , Masculino , Estimulação Luminosa , Ratos Long-Evans , Tempo de Reação/fisiologia , Recompensa
17.
Eur J Pharm Sci ; 33(1): 20-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18023332

RESUMO

Despite the availability of numerous crystal engineering techniques, generating drug-rich microparticles with a predetermined size, morphology and crystallinity still represents a significant challenge. A microparticle manufacturing method has recently been developed that attempts to 'shield' the physicochemical properties of micronised drugs by the application of a microfine polymer coating. The aims of this study were to investigate the nature of the drug-polymer interactions and determine the effects of this manufacturing strategy upon release of the drug from the microparticles. The adsorption of poly(vinyl alcohol) (PVA) on the micronised hydrophobic drug surface was found to reach equilibrium between 23 and 27 h. The Freundlich isotherm model was shown to give the most accurate fit to the experimental data and thus multilayer adsorption was assumed. The adsorptive capacity (1/n) was specific to the substrate and PVA grade. An increase in the PVA (%) hydrolysis value caused 1/n to increase from 0.76 to 1.05 using budesonide and from 0.31 to 0.79 when betamethasone valerate (BMV) was used. Increasing the molecular weight of the adsorbing polymer caused a reduction in the strength of PVA-adsorbate interaction when budesonide was used as the substrate (from 0.76 to 0.59), whereas a three-fold increase (from 0.31 to 0.86) was achieved when the BMV substrate was employed. A proportion of the adsorbed polymer was shown to remain associated with the substrate during the spray-drying process and the polymer coating resulted in a significantly higher (p<0.05, ANOVA) amount of drug release in 60 min (ca. 100%) compared to budesonide alone.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Microesferas , Preparações Farmacêuticas/química , Álcool de Polivinil/química , Corticosteroides/química , Corticosteroides/farmacocinética , Adsorção , Algoritmos , Valerato de Betametasona/química , Valerato de Betametasona/farmacocinética , Budesonida/química , Budesonida/farmacocinética , Calibragem , Colorimetria/métodos , Liofilização/métodos , Hidrólise , Cinética , Peso Molecular , Tamanho da Partícula , Preparações Farmacêuticas/metabolismo , Polímeros/química , Solubilidade , Tecnologia Farmacêutica/métodos , Termodinâmica
18.
Sci Rep ; 8(1): 6831, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717224

RESUMO

The intraoperative in-vivo mechanical function of the left ventricle has been studied thoroughly using echocardiography in the past. However, due to technical and anatomical issues, the ultrasound technology cannot easily be focused on the right side of the heart during open-heart surgery, and the function of the right ventricle during the intervention remains largely unexplored. We used optical imaging and digital image correlation for the characterization of the right ventricle motion and deformation during open-heart surgery. This work is a pilot study focusing on one patient only with the aim of establishing the framework for long term research. These experiments show that optical imaging and the analysis of the images can be used to obtain similar parameters, and partly at higher accuracy, for describing the mechanical functioning of the heart as the ultrasound technology. This work describes the optical imaging based method to characterize the mechanical response of the heart in-vivo, and offers new insight into the mechanical function of the right ventricle.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ventrículos do Coração/fisiopatologia , Imagem Óptica/instrumentação , Imagem Óptica/métodos , Esternotomia , Vetorcardiografia/métodos , Diástole/fisiologia , Finlândia , Hospitais Universitários , Humanos , Projetos Piloto , Pulso Arterial , Software , Sístole/fisiologia
19.
Egypt J Forensic Sci ; 7(1): 11, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775904

RESUMO

BACKGROUND: Medico legal forensic entomology is the science and study of cadaveric arthropods related to criminal investigations. The study of beetles is particularly important in forensic cases. This can be important in determining the time of death and also obtain qualitative information about the location of the crime. The aim of this study was to introduce the Saprinus planiusculus on a rat carrion as a beetle species of forensic importance in Khuzestan province. METHODS: This study was carried out using a laboratory bred rat (Wistar rat) as a model for human decomposition. The rat was killed by contusion and placed in a location adjacent to the Karun River. Observations and collections of beetles were made daily during May to July 2015. RESULTS: Decomposition time for rat carrion lasted 38 days and S. planiusculus was seen in the fresh to post decay stages of body decomposition and the largest number of this species caught in the decay stage. CONCLUSION: The species of beetle found in this case could be used in forensic investigations, particularly during the warm season in the future.

20.
Arch Razi Inst ; 72(3): 203-208, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-30341942

RESUMO

Culicidae are highly important for public health as they can be vectors of diseases and are responsible for a wide spectrum of infections. Five collection sites were selected randomly with regards to existing facilities in Firouzabad County. For collecting larvae and total catch for adult mosquitoes, sampling was carried out by dipping technique for collecting larvae and total catch for adult mosquitoes. A total of 689 adults and 1313 larvae of Culicidae were collected, of which 3 genera and 6 species of Culicidae were recognized, namely, Anopheles superpictus, Anopheles d&rsquo;thali, Culex sinaiticus, Culex theileri, Culex mimeticus, and Culiseta longiareolata. Cx. theileri was the most frequent Culicidae collected at Firouzabad, with a total of 613 and 247 larval and adult specimens, respectively. The highest number of mosquitoes was collected in June (31.1%) and the lowest in May (3.4%). The mean temperatures in June and May were 31.3˚C and 28.2˚C, respectively. We found some vectors that are of medical and veterinary importance; our results could be applied in vector control programs that aim at eradication or control of mosquitoes in this area.


Assuntos
Distribuição Animal , Culicidae/classificação , Mosquitos Vetores/classificação , Animais , Culicidae/crescimento & desenvolvimento , Culicidae/fisiologia , Irã (Geográfico) , Larva/classificação , Larva/fisiologia , Mosquitos Vetores/crescimento & desenvolvimento , Mosquitos Vetores/fisiologia , Estações do Ano
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