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1.
J Mater Sci Mater Med ; 35(1): 36, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900219

RESUMO

Calcium phosphate cements, primarily brushite cements, require the addition of setting retarders to ensure adequate processing time and processability. So far, citric acid has been the primary setting retarder used in this context. Due to the poor biocompatibility, it is crucial to explore alternative options for better processing. In recent years, the setting retarder phytic acid (IP6) has been increasingly investigated. This study investigates the biological behaviour of calcium phosphate cements with varying concentrations of IP6, in addition to their physical properties. Therefore cytocompatibility in vitro testing was performed using osteoblastic (MG-63) and osteoclastic (RAW 264.7 differentiated with RANKL) cells. We could demonstrate that the physical properties like the compressive strength of specimens formed with IP6 (brushite_IP6_5 = 11.2 MPa) were improved compared to the reference (brushite = 9.8 MPa). In osteoblast and osteoclast assays, IP6 exhibited significantly better cytocompatibility in terms of cell activity and cell number for brushite cements up to 11 times compared to the brushite reference. In contrast, the calcium-deficient hydroxyapatite (CDHA) cements produced similar results for IP6 (CDHA_IP6_0.25 = 27.0 MPa) when compared to their reference (CDHA = 21.2 MPa). Interestingly, lower doses of IP6 were found to be more effective than higher doses with up to 3 times higher. Additionally, IP6 significantly increased degradation in both passive and active resorption. For these reasons, IP6 is emerging as a strong new competitor to established setting retarders such as citric acid. These cements have potential applications in bone augmentation, the stabilisation of non-load bearing fractures (craniofacial), or the cementation of metal implants.


Assuntos
Cimentos Ósseos , Fosfatos de Cálcio , Teste de Materiais , Osteoblastos , Osteoclastos , Ácido Fítico , Ácido Fítico/química , Animais , Fosfatos de Cálcio/química , Camundongos , Cimentos Ósseos/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Células RAW 264.7 , Humanos , Osteoclastos/efeitos dos fármacos , Força Compressiva , Materiais Biocompatíveis/química , Durapatita/química
2.
J Funct Biomater ; 15(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38667565

RESUMO

Bone defects resulting from trauma, diseases, or surgical procedures pose significant challenges in the field of oral and maxillofacial surgery. The development of effective bone substitute materials that promote bone healing and regeneration is crucial for successful clinical outcomes. Calcium phosphate cements (CPCs) have emerged as promising candidates for bone replacement due to their biocompatibility, bioactivity, and ability to integrate with host tissues. However, there is a continuous demand for further improvements in the mechanical properties, biodegradability, and bioactivity of these materials. Dual setting of cements is one way to improve the performance of CPCs. Therefore, silicate matrices can be incorporated in these cements. Silicate-based materials have shown great potential in various biomedical applications, including tissue engineering and drug delivery systems. In the context of bone regeneration, silicate matrices offer unique advantages such as improved mechanical stability, controlled release of bioactive ions, and enhanced cellular responses. Comprehensive assessments of both the material properties and biological responses of our samples were conducted. Cytocompatibility was assessed through in vitro testing using osteoblastic (MG-63) and osteoclastic (RAW 264.7) cell lines. Cell activity on the surfaces was quantified, and scanning electron microscopy (SEM) was employed to capture images of the RAW cells. In our study, incorporation of tetraethyl orthosilicate (TEOS) in dual-curing cements significantly enhanced physical properties, attributed to increased crosslinking density and reduced pore size. Higher alkoxysilyl group concentration improved biocompatibility by facilitating greater crosslinking. Additionally, our findings suggest citrate's potential as an alternative retarder due to its positive interaction with the silicate matrix, offering insights for future dental material research. This paper aims to provide an overview of the importance of silicate matrices as modifiers for calcium phosphate cements, focusing on their impact on the mechanical properties, setting behaviour, and biocompatibility of the resulting composites.

3.
Physiother Res Int ; 29(3): e2090, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38685678

RESUMO

BACKGROUND/OBJECTIVE: Constraint-induced movement therapy (CIMT), a therapy that encourages the use of the affected upper limb through intensive functional tasks, effectively promotes upper limb function in patients with chronic stroke. This study determined the effectiveness of CIMT using telerehabilitation compared with traditional CIMT in improving mild to moderate upper limb motor function in adult patients with chronic stroke. METHODS: Eligible studies were identified by searching electronic databases and scanning the reference lists of articles. Review Manager 5.4 was used to determine the pooled mean effect size of the standardized mean difference and 95% confidence interval for the group comparison. Visual heterogeneity, I2 statistic, and chi-square test were used to measure the heterogeneity between the included studies. We evaluated the quality of evidence using GRADEpro GDT, software for creating evidence summaries and healthcare recommendations. RESULTS: Two randomized controlled trials were included in this review. A total of 109 participants (70 male, 39 female) were evaluated. The time since the stroke was ≥6 months in one study and ≥1 year in another study. Improvements in upper limb motor function while performing functional movements were measured using the Wolf Motor Function Test. The evidence for the effectiveness of CIMT using telerehabilitation compared with traditional CIMT in improving the upper extremity function in patients with chronic stroke is of moderate quality. This suggests no significant difference between the groups (mean difference [95% CI]: -0.04 [-0.42, 0.33]). CONCLUSIONS: CIMT using telerehabilitation is not superior to traditional CIMT in improving patients' upper extremity motor function with chronic stroke. CIMT using telerehabilitation may improve access to treatment, minimize SARS-CoV-2 risk, and reduce travel in patients with chronic stroke.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Telerreabilitação , Extremidade Superior , Adulto , Feminino , Humanos , Masculino , Doença Crônica , COVID-19/reabilitação , Terapia por Exercício/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , SARS-CoV-2 , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral/métodos , Telerreabilitação/métodos , Resultado do Tratamento , Extremidade Superior/fisiopatologia
4.
J Osteopath Med ; 124(8): 353-363, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38444081

RESUMO

CONTEXT: Myofascial pain syndrome (MPS) is primarily characterized by myofascial trigger points related to fascial adhesions. MPS hinders fascial flexibility and mobility, leading to myofascial limitations, dysfunctional movement, and limitation of motion (LOM). OBJECTIVES: This study determined the association of age, sex, type of work, symptom chronicity, symptom laterality, cervical LOM, altered direction of fascial displacement, and magnitude of superficial fascial displacement during active cervical flexion with the clinical diagnosis of MPS. METHODS: A cross-sectional study selectively included MPS and non-MPS participants from different workplaces from January to October 2019. The MPS group exhibited clinical symptoms like tender spots, recognized pain patterns, and local twitch response upon palpation, often accompanied by cervical LOM. The non-MPS group lacked these symptoms, and those with certain pre-existing conditions or recent physiotherapy were not part of the study. Participants performed cervical active range of motion (AROM) while a sonographer recorded superficial fascial displacement utilizing ultrasound, which was later analyzed by three physiotherapists with the Tracker. Aiming for a multiple regression R-squared of 0.2, the target was 384 participants to account for a 20 % dropout, resulting in 307 participants after attrition. To explore the relationships between MPS and various factors, logistic regression models, rigorously tested for reliability and validity, were utilized. RESULTS: In the study, there were 192 participants with MPS and 137 without MPS. The median ages were 33 years for the non-MPS group and 38 years for the MPS group. The adjusted model found significant links for sex (odds ratio [OR]=2.63, p<0.01), symptom chronicity (OR=8.28, p<0.01), and cervical LOM (OR=3.77, p=0.01). However, age and the presence of nodules/taut bands were not statistically significant (p>0.05). Also, the type of work, the direction of fascial displacement, and the difference in superficial fascial displacement during cervical flexion did not show a significant association with the clinical diagnosis of MPS (p>0.05). The adjusted model had a sensitivity of 73.80 % and a specificity of 81.34 %, correctly identifying 84.66 % of positive cases and 68.99 % of negative ones, resulting in an overall accuracy of 76.95 % in predicting MPS. CONCLUSIONS: We provided an in-depth examination of MPS, identifying sex, duration of symptoms, and cervical LOM as significant predictive factors in its diagnosis. The study emphasizes the critical role of these variables in the accurate diagnosis of MPS, while delineating the comparatively minimal diagnostic value of other factors such as age, type of occupation, presence of nodules or taut bands, and variations in fascial displacement. This study underscores the imperative for further scholarly inquiry into the role of fascial involvement in musculoskeletal disorders, with the objective of enhancing both the theoretical understanding and diagnostic practices in this medical domain.


Assuntos
Fáscia , Síndromes da Dor Miofascial , Amplitude de Movimento Articular , Humanos , Estudos Transversais , Feminino , Síndromes da Dor Miofascial/diagnóstico , Síndromes da Dor Miofascial/fisiopatologia , Masculino , Adulto , Pessoa de Meia-Idade , Amplitude de Movimento Articular/fisiologia , Fáscia/diagnóstico por imagem , Fáscia/fisiopatologia , Vértebras Cervicais/fisiopatologia , Vértebras Cervicais/diagnóstico por imagem , Ultrassonografia , Adulto Jovem , Diagnóstico Diferencial
5.
Ultrason Sonochem ; 100: 106602, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37741021

RESUMO

The present study proposes the first mechanistic model accounting for the most meaningful physico-chemical phenomena taking place in liquid phase adsorption processes under ultrasound. Initially, this study was aimed at developing an easy-to-make and easy-to-recover piezocatalyst for the degradation of RhB in water by combining the high piezocatalytical performance of BaTiO3 with a compatible piezoelectric support such as PVDF, manufactured by a customised additive manufacturing - direct ink writing system with in-situ poling. However, initial results showed that the resulting PVDF-BaTiO3 composite slabs performed worse than BaTiO3 piezocatalysts on their own, and that poling did not have any effect on their performance (82% RhB removal after 2 h when using either poled or unpoled PVDF-BaTiO3 composite slabs compared to 92% RhB removal after 2 h in presence of BaTiO3 piezocatalysts). Further investigation with pure PVDF materials demonstrated that, instead of piezocatalysis, synergistic ultrasound-assisted adsorption and sonochemical degradation were taking place, enabling the removal of >95% of the dye within 40 min of ultrasound treatment in the presence of 4 g L-1 of additive manufactured PVDF slabs. The results of this study and their evaluation with the mechanistic model proposed for liquid phase adsorption under ultrasound suggest that the adsorption of RhB on additive manufactured PVDF slabs was enhanced by the structure, higher specific surface ratio and higher volume of mesopores achieved through the 3D-printing process, as well as the minimisation of film resistance to mass transport due to ultrasound. Moreover, adsorption on additive manufactured PVDF enhanced the sonochemical degradation of the dye due to its high concentration in the adsorbed phase. This study demonstrates that adsorption processes, especially in the presence of PVDF materials, may be significantly more important in piezocatalysis than what has been reported to date, to the point that the synergistic combination of sono-adsorption and sonochemical degradation in presence of additive-manufactured PVDF slabs may be enough to achieve high removal rates of dyes in water.

6.
J Bodyw Mov Ther ; 35: 238-243, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37330776

RESUMO

BACKGROUND AND PURPOSE: Palpation evaluates the fascia, a three-dimensional web of connective tissues. We propose altered fascia system displacement in patients with myofascial pain syndrome. This study determined the concurrent validity of palpation and musculoskeletal ultrasound (MSUS) videos played on Windows Media Player 10 (WMP) when evaluating the direction of the fascia system's displacement at the end of the cervical active range of motion (AROM). METHODS: This cross-sectional study used palpation as index test and MSUS videos on WMP as reference test. First, three physical therapists palpated right and left shoulders for each cervical AROM. Second, during cervical AROM, PT-Sonographer recorded the fascia system displacement. Third, using the WMP, the physical therapists evaluated the direction of skin, superficial and deep fascia displacements at the end of cervical AROM. MedCalc Version 19.5.3 determined the "exact" Clopper-Pearson Interval (CPI). RESULTS: We found strong accuracy between palpation and MSUS videos on WMP when determining the direction of skin displacement during cervical flexion and extension (CPI= 78.56 to 96.89). There was moderate agreement between palpation and MSUS videos on WMP when determining the direction of the skin, superficial fascia, and deep fascia displacements during cervical lateral flexion and rotation (CPI= 42.25 to 64.13). CONCLUSION: Skin palpation during cervical flexion and extension may be useful in evaluating patients with myofascial pain syndrome (MPS). It is unclear what fascia system was evaluated when shoulders were palpated at the end of cervical lateral flexion and rotation. Palpation as diagnostic tool for MPS was not investigated.


Assuntos
Fibromialgia , Síndromes da Dor Miofascial , Humanos , Estudos Transversais , Síndromes da Dor Miofascial/diagnóstico por imagem , Fáscia/diagnóstico por imagem , Palpação , Amplitude de Movimento Articular
7.
Biomedicines ; 11(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36979873

RESUMO

Chronic inflammation is demonstrated to play a direct role in carcinogenesis. Our exploratory study aimed to assess the potential added value of two inflammation biomarkers, chitotriosidase and neopterin, in follow-up evaluation of patients with colorectal cancer (CRC). An observational exploratory study was conducted. Patients with CRC and matched controls (1:1, age, sex, and living environment) were evaluated. The patients with CRC (CRC group) and controls were assessed at baseline (before surgical intervention for patients with CRC). Patients with CRC were also evaluated at 1-year follow-up. Significantly more patients with blood group A (54.5% vs. 25.0%) and smokers (50.0% vs. 22.7%) were in the CRC group. The serum values of chitotriosidase and neopterin were higher in CRC patients than in controls, but only neopterin reached the conventional level of statistical significance (p-value = 0.015). The circulating chitotriosidase and neopterin values decreased significantly at 1-year follow-up (p-value < 0.0001). Patients with higher N- and M-stage showed statistically significant higher levels of chitotriosidase and neopterin at baseline and 1-year follow-up (p-values < 0.03). Circulating chitotriosidase levels also showed statistically significant differences regarding baseline and 1-year follow-up on patients with CRC and different differentiation grades (p-values < 0.02). The circulating levels of neopterin significantly decreased at 1-year follow-up, indicating its potential as a prognostic marker. The circulating values of chitotriosidase and neopterin exhibit significant differences in patients with than without recurrences. Our results support further evaluation of chitotriosidase and neopterin as prognostic markers in patients with CRC.

8.
Opt Express ; 29(19): 29813-29827, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34614719

RESUMO

Controlling the wavefront of an extreme ultraviolet (XUV) high-order harmonic beam during the generation process offers the capability of modifying the beam properties without resorting to any XUV optics. By characterizing the XUV intensity profile and wavefront, we quantitatively retrieve both the size and the position of the waist of each harmonic generated in an argon jet. We show that optics-free focusing can occur under specific generating conditions leading to XUV focii of micrometer size. We also demonstrate that each focus is located at distinct longitudinal positions. Using this remarkable XUV wavefront control combined with near focus spatial selection, we experimentally demonstrate efficient and adjustable spectral filtering of the XUV beam, along with a strong rejection of the fundamental beam, without using any XUV optics. The experimental results are compared with simulations providing the impact of the filtering on the temporal profile of the XUV field. It shows that the attosecond structure is preserved and that the beam is more homogeneous after the filtering, thereby reducing the longitudinal focii shift. This is a major step to achieve high XUV intensity and probing ultrafast processes with an improved resolution.

9.
J Bodyw Mov Ther ; 27: 239-246, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34391240

RESUMO

BACKGROUND: Restricted shoulder fascia displacement may be an etiological factor for myofascial pain syndrome. A diagnostic ultrasound video can follow deep fascia displacement during active cervical movements. Trackers can be applied to videos to convert deep fascia displacement into data points. This study reports on assessors' reliability in evaluating direction and quantifying upper trapezius' deep fascia displacement during active cervical movements. METHODS: PT-Sonographer 1 recorded deep fascia displacement of upper trapezius for three sets using HS1 Konica Minolta diagnostic ultrasound. The recording sequence used was cervical flexion, extension, right lateral flexion, left lateral flexion, right rotation, and left rotation. The three assessors used the tracker to determine direction of deep fascia displacement. PT-Sonographer 1 used the tracker three times in quantifying deep fascia displacement. Intraclass correlation coefficient and Kappa determined the assessors' intra-tester and inter-tester reliability. RESULTS: Ten participants were included in the study with a mean±(SD) age of 37±(6). All the assessors had acceptable intra-tester reliability in determining deep fascia displacement on tracker (ICC≥0.40). All assessors had clinically unacceptable inter-tester reliability in determining deep fascia displacement when tracking right rotation (ICC < 0.40). PT-Sonographer 1 had clinically unacceptable intra-tester reliability in determining deep fascia displacement when tracking left rotation (ICC<0.40). CONCLUSION: We report clinically acceptable assessors' reliability in determining direction and total deep fascia displacement when tracking diagnostic ultrasound videos of cervical flexion, extension, and lateral flexion. Checking for reliable deep fascia displacements may distinguish MPS from non-MPS individuals increasing the utility of diagnostic ultrasound machine and tracker in clinical practice.


Assuntos
Músculos Superficiais do Dorso , Vértebras Cervicais/diagnóstico por imagem , Fáscia/diagnóstico por imagem , Humanos , Movimento , Projetos Piloto , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Músculos Superficiais do Dorso/diagnóstico por imagem
10.
J Bodyw Mov Ther ; 24(3): 273-281, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32826000

RESUMO

BACKGROUND: Trapezius Myalgia (TM) is characterized by shoulder pain and dysfunction. Kinesio Taping is commonly used in symptom management of TM. Biomechanical Taping (BMT), a novel intervention, may provide equally effective management. OBJECTIVES: This paper reports on the effectiveness of Biomechanical Taping compared with Kinesio Taping in improving shoulder pain, active range of motion (AROM), and function. METHODS: Two groups of participants with TM were recruited through simple random sampling of participants from nine call centers and purposively-sampled participants from one fast-food chain and one community based rehabilitation center in Manila, Philippines. Participants were randomly allocated to either Kinesio Taping or biomechanical taping group in a double-blind clinical trial. Irrespective of the type of taping, participants performed gentle passive stretching of upper trapezius for six times each held for 30 s on Days 1, 3, and 5. On Days 2 and 4, participants performed gentle passive stretch of upper trapezius three times a day. Pre- and post-intervention measures were taken of Visual Analogue Scale for pain intensity, AROM for shoulder movement, and Disability of Arm, Shoulder, and Hand for function. RESULTS: Of 68 participants, 62 had shoulder symptoms secondary to TM. Similar significant within group improvements were found for Visual Analogue Scale scores, and Disability of Arm, Shoulder and Hand for biomechanical taping and Kinesio Taping interventions when comparing between group results (p < 0.05). CONCLUSION: Biomechanical Taping appears to be as effective as Kinesio Taping in the short term in decreasing pain and improving function of individuals with TM. Both taping techniques did not restrict shoulder AROM of included participants. MESH TERMS: Athletic Tape, Myalgia, Pain Measurements, Shoulder Pain NON-MESH TERMS: Biomechanical Taping Technique.


Assuntos
Fita Atlética , Músculos Superficiais do Dorso , Humanos , Mialgia , Filipinas , Amplitude de Movimento Articular , Dor de Ombro/terapia , Resultado do Tratamento
11.
Artigo em Inglês | MEDLINE | ID: mdl-32180989

RESUMO

Between 2010 and 2019 the international health care organization Partners In Health (PIH) and its sister organization Zanmi Lasante (ZL) mounted a long-term response to the 2010 Haiti earthquake, focused on mental health. Over that time, implementing a Theory of Change developed in 2012, the organization successfully developed a comprehensive, sustained community mental health system in Haiti's Central Plateau and Artibonite departments, directly serving a catchment area of 1.5 million people through multiple diagnosis-specific care pathways. The resulting ZL mental health system delivered 28 184 patient visits and served 6305 discrete patients at ZL facilities between January 2016 and September 2019. The experience of developing a system of mental health services in Haiti that currently provides ongoing care to thousands of people serves as a case study in major challenges involved in global mental health delivery. The essential components of the effort to develop and sustain this community mental health system are summarized.

12.
J Bodyw Mov Ther ; 23(2): 405-416, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31103128

RESUMO

INTRODUCTION: Lateral epicondylalgia (LE) is a musculoskeletal injury involving the common extensor origin in elbow manifesting as pain and ineffective handgrip affecting the daily activities of the individuals with LE. OBJECTIVES: This study determined the effectiveness of Standard Biomechanical Taping (SBMT), Vector Correcting Dysfunction Techniques 1 (VCDT 1) and Vector Correcting Dysfunction Technique 2 (VCDT 2); and compared their differences on effects on pain, grip strength and daily functions of individual with unilateral LE. METHODS: A cross-over study design was used. The senior investigator applied three BMT techniques namely: a. SBMT, b. VCDT 1, and c. VCDT 2. On Day 1, SBMT and VCDT1 were randomly assigned. On Day 3, either SBMT or VCDT1 not performed on Day 1 was applied to LE elbows. On Day 5, VCDT2 was applied on LE elbows. Visual Analogue Scale (VAS), Static Maximum Handgrip Strength Test (SMHGT) and Patient-Rated Tennis Elbow Evaluation (PRTEE) were used as outcome measures administered by three blinded junior investigators. On Days 1, 3, and 5, VAS and SMGHT were administered before and during BMT application. PRTEE was administered on Days 1 and 12. RESULTS: The following were found in this study: a. significantly decreased VAS scores at Days 1, 3, and 5 of BMT application (p < 0.05); b. significantly improved final VAS, SMHGT strength and PRTEE scores on Day 12 compared to baseline scores on Day 1 (p = /<0.01); and c. significantly decreased VAS scores when using SBMT compared to VCDT2 (p < 0.05). CONCLUSION: BMT is a novel taping technique effective in decreasing lateral elbow pain, increasing handgrip strength and improving function of patients with LE. BMT can be applied on painful elbows effecting a better grip among patients with LE.


Assuntos
Fita Atlética , Força da Mão/fisiologia , Modalidades de Fisioterapia , Cotovelo de Tenista/terapia , Adulto , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Escala Visual Analógica
13.
Toxicon ; 151: 74-78, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29890231

RESUMO

In the American continent, larval forms (caterpillars) of the Lonomia genus can cause systemic reactions in human beings. In this Paper, we report the third case of Lonomia envenoming recorded in French Guiana in 25 years, and the first in which specific antivenom was administered. Severe symptoms of the envenoming were observed in our patient including pain; coagulopathy and systemic hemorrhage. They are caused by skin contact with caterpillars. Recovery, however, was quite satisfactory thanks to the international cooperation of the health authorities in both France and Brazil.


Assuntos
Antivenenos/uso terapêutico , Venenos de Artrópodes/toxicidade , Transtornos da Coagulação Sanguínea/induzido quimicamente , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Mordeduras e Picadas de Insetos/tratamento farmacológico , Mariposas/fisiologia , Animais , Brasil , Feminino , Guiana Francesa , Humanos , Mordeduras e Picadas de Insetos/patologia , Larva/fisiologia , Pessoa de Meia-Idade
14.
Neuron ; 98(5): 935-944.e5, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29779943

RESUMO

Bidirectional communication between neurons and astrocytes shapes synaptic plasticity and behavior. D-serine is a necessary co-agonist of synaptic N-methyl-D-aspartate receptors (NMDARs), but the physiological factors regulating its impact on memory processes are scantly known. We show that astroglial CB1 receptors are key determinants of object recognition memory by determining the availability of D-serine at hippocampal synapses. Mutant mice lacking CB1 receptors from astroglial cells (GFAP-CB1-KO) displayed impaired object recognition memory and decreased in vivo and in vitro long-term potentiation (LTP) at CA3-CA1 hippocampal synapses. Activation of CB1 receptors increased intracellular astroglial Ca2+ levels and extracellular levels of D-serine in hippocampal slices. Accordingly, GFAP-CB1-KO displayed lower occupancy of the co-agonist binding site of synaptic hippocampal NMDARs. Finally, elevation of D-serine levels fully rescued LTP and memory impairments of GFAP-CB1-KO mice. These data reveal a novel mechanism of in vivo astroglial control of memory and synaptic plasticity via the D-serine-dependent control of NMDARs.


Assuntos
Astrócitos/metabolismo , Neurônios/metabolismo , Receptor CB1 de Canabinoide/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Reconhecimento Psicológico/fisiologia , Serina/metabolismo , Sinapses/metabolismo , Animais , Região CA1 Hipocampal/metabolismo , Região CA3 Hipocampal/metabolismo , Hipocampo , Técnicas In Vitro , Potenciação de Longa Duração , Memória , Camundongos , Camundongos Knockout , Plasticidade Neuronal , Receptor CB1 de Canabinoide/metabolismo
15.
J Phys Condens Matter ; 30(4): 044003, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29087359

RESUMO

Understanding the electronic structure of metal oxide semiconductors is crucial to their numerous technological applications, such as photoelectrochemical water splitting and solar cells. The needed experimental and theoretical knowledge goes beyond that of pristine bulk crystals, and must include the effects of surfaces and interfaces, as well as those due to the presence of intrinsic defects (e.g. oxygen vacancies), or dopants for band engineering. In this review, we present an account of the recent efforts in predicting and understanding the optoelectronic properties of oxides using ab initio theoretical methods. In particular, we discuss the performance of recently developed dielectric-dependent hybrid functionals, providing a comparison against the results of many-body GW calculations, including G 0 W 0 as well as more refined approaches, such as quasiparticle self-consistent GW. We summarize results in the recent literature for the band gap, the band level alignment at surfaces, and optical transition energies in defective oxides, including wide gap oxide semiconductors and transition metal oxides. Correlated transition metal oxides are also discussed. For each method, we describe successes and drawbacks, emphasizing the challenges faced by the development of improved theoretical approaches. The theoretical section is preceded by a critical overview of the main experimental techniques needed to characterize the optoelectronic properties of semiconductors, including absorption and reflection spectroscopy, photoemission, and scanning tunneling spectroscopy (STS).

16.
Toxicon ; 151: p. 74-78, 2018.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15323

RESUMO

In the American continent, larval forms (caterpillars) of the Lonomia genus can cause systemic reactions in human beings. In this Paper, we report the third case of Lonomia envenoming recorded in French Guiana in 25 years, and the first in which specific antivenom was administered. Severe symptoms of the envenoming were observed in our patient including pain; coagulopathy and systemic hemorrhage. They are caused by skin contact with caterpillars. Recovery, however, was quite satisfactory thanks to the international cooperation of the health authorities in both France and Brazil.

17.
Elife ; 62017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28598327

RESUMO

The subunit composition of synaptic NMDA receptors (NMDAR), such as the relative content of GluN2A- and GluN2B-containing receptors, greatly influences the glutamate synaptic transmission. Receptor co-agonists, glycine and D-serine, have intriguingly emerged as potential regulators of the receptor trafficking in addition to their requirement for its activation. Using a combination of single-molecule imaging, biochemistry and electrophysiology, we show that glycine and D-serine relative availability at rat hippocampal glutamatergic synapses regulate the trafficking and synaptic content of NMDAR subtypes. Acute manipulations of co-agonist levels, both ex vivo and in vitro, unveil that D-serine alter the membrane dynamics and content of GluN2B-NMDAR, but not GluN2A-NMDAR, at synapses through a process requiring PDZ binding scaffold partners. In addition, using FRET-based FLIM approach, we demonstrate that D-serine rapidly induces a conformational change of the GluN1 subunit intracellular C-terminus domain. Together our data fuels the view that the extracellular microenvironment regulates synaptic NMDAR signaling.


Assuntos
Glicina/metabolismo , Hipocampo/fisiologia , Receptores de N-Metil-D-Aspartato/agonistas , Serina/metabolismo , Sinapses/fisiologia , Animais , Ratos
18.
J Pharm Policy Pract ; 10: 7, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28116107

RESUMO

BACKGROUND: To assess the effect of policies supporting local medicine production to improve access to medicines. METHODS: We adapted the WHO/HAI instruments measuring medicines availability and prices to differentiate local from imported products, then pilot tested in Ethiopia and Tanzania. In each outlet, prices were recorded for all products in stock for medicines on a country-specific list. Government procurement prices were also collected. Prices were compared to an international reference and expressed as median price ratios (MPR). RESULTS: The Ethiopian government paid more for local products (median MPR = 1.20) than for imports (median MPR = 0.84). Eight of nine medicines procured as both local and imported products were cheaper when imported. Availability was better for local products compared to imports, in the public (48% vs. 19%, respectively) and private (54% vs. 35%, respectively) sectors. Patient prices were lower for imports in the public sector (median MPR = 1.18[imported] vs. 1.44[local]) and higher in the private sector (median MPR = 5.42[imported] vs. 1.85[local]). In the public sector, patients paid 17% and 53% more than the government procurement price for local and imported products, respectively. The Tanzanian government paid less for local products (median MPR = 0.69) than imports (median MPR = 1.34). In the public sector, availability of local and imported products was 21% and 32% respectively, with patients paying slightly more for local products (median MPR = 1.35[imported] vs. 1.44[local]). In the private sector, local products were less available (21%) than imports (70%) but prices were similar (median MPR = 2.29[imported] vs. 2.27[local]). In the public sector, patients paid 135% and 65% more than the government procurement price for local and imported products, respectively. CONCLUSIONS: Our results show how local production can affect availability and prices, and how it can be influenced by preferential purchasing and mark-ups in the public sector. Governments need to evaluate the impact of local production policies, and adjust policies to protect patients from paying more for local products.

19.
Genome Announc ; 4(1)2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26744375

RESUMO

A draft genome sequence of Lactobacillus plantarum 2025 was derived using Ion Torrent sequencing technology. The total size of the assembly (3.33 Mb) was in agreement with the genome sizes of other strains of this species. The data will assist in revealing the genes responsible for the specific properties of this strain.

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