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1.
Psychol Health Med ; : 1-18, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700271

RESUMO

Antibiotic resistance (AR) rates in Vietnam are among the highest in Asia, and recent infections due to multi-drug resistance in the country have caused thousands of deaths each year. This study investigated a Vietnamese community's preferences for antibiotic treatment and its knowledge and attitudes regarding antibiotics. A discrete choice experiment-based survey was developed and administered to the population of interest. The respondents were given sociodemographic-, knowledge- and attitude-related items and 17 pairs of choice tasks. Two hypothetical options were included in each choice task. Latent class analysis was conducted to determine the differences among the respondents' preferences. Among 1,014 respondents, 805 (79.4%) gave valid questionnaires. A three-latent-class model with four covariates (age, healthcare-related education or career, occupation, and attitude classifications) was used in the analysis. All five attributes significantly influenced the respondents' decisions. The majority, including young employed respondents with non-healthcare-related work or education, found treatment failure more important. Older respondents who had healthcare-related education/careers and/or appropriate antibiotic use- and antibiotics resistance-related attitudes, regarded contribution to antibiotic resistance as an important attribute in selecting antibiotic treatments. Unemployed individuals with correct knowledge identified the cost of antibiotic treatment as the most essential decision-making factor. Findings suggest minimal antibiotic impact on resistance; only 7.83% view it as amajor concern. The respondents exhibited substantial preference heterogeneity, and the general Vietnamese public had poor knowledge of and attitudes toward antibiotic use and antibiotic resistance. This study emphasizes the need for individual responsibility for antibiotic resistance and appropriate antibiotic use.

2.
Langmuir ; 39(11): 3853-3861, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36893476

RESUMO

Magnesium diboride (MgB2) has demonstrated, theoretically and experimentally, promise as a candidate material for hydrogen storage and has thus attracted much contemporary research interest. To study hydrogen gas adsorption on MgB2 thin films using a quartz crystal microbalance (QCM)─a workhorse apparatus for this specific experiment─MgB2 must be deposited uniformly on the active surface of the QCM without damaging the quartz's performance. In work presented here, a wet-chemistry colloid synthesis and deposition process of a MgB2 thin film on a gold (Au) surface was established to avoid the extreme conditions of conventional physical deposition methods. This process also counteracts the unwanted phenomena of drying droplets on a solid surface, particularly the coffee-ring effect. To verify the normal function of the QCM after MgB2 deposition and its ability to obtain meaningful data, simple gas adsorption tests were conducted on the QCM, and the MgB2 film on the QCM was characterized with X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) for elemental analysis and surface roughness, respectively. To obtain information about the thickness and the involvement of the coffee-ring effect, the same synthesis route was applied on a similar gold substrate─an evaporated Au film on glass. XPS characterization of the film and its precursor suspension shows the potential existence of both MgB2 and its oxide forms. The film's thickness on evaporated Au was measured by scanning transmission electron microscopy (STEM) to be 3.9 nm. The resulting samples show mitigation of the coffee-ring effect through roughness measurements with AFM at two scan sizes of 50 × 50 and 1 × 1 µm2.

3.
Sens Actuators B Chem ; 376(Pt A)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688105

RESUMO

Biofilms are complex three-dimensional microbial communities that adhere to a variety of surfaces and interact with their surroundings. Because of the dynamic nature of biofilm formation, establishing a uniform technique for quantifying and monitoring biofilm volume, shape, and features in real-time is challenging. Herein, we describe a noninvasive electrochemical impedance approach for real-time monitoring of dental plaque-derived multispecies biofilm growth on a range of substrates. A working equation relating electrochemical impedance to live biofilm volume has been developed that is applicable to all three surfaces examined, including glass, dental filling resin, and Ca2+-releasing resin composites. Impedance changes of 2.5, 35, 50, and 65% correlated to biofilm volumes of 0.10 ± 0.01, 16.9 ± 2.2, 29.7 ± 2.3, and 38.6 ± 2.8 µm3/µm2, respectively. We discovered that glass, dental filling resin, and Ca2+-releasing dental composites required approximately 3.5, 4.5, and 6 days, respectively, to achieve a 50% change in impedance. The local pH change at the biofilm-substrate interfaces also monitored with potentiometry pH microsensor, and pH change varied according to biofilm volume. This impedance-based technique can be a useful analytical method for monitoring the growth of biofilms on a variety of substrates in real-time. Therefore, this technique may be beneficial for examining antibacterial properties of novel biomaterials.

4.
Environ Manage ; 72(2): 262-274, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36653481

RESUMO

The soaring economic development of export activities of handicrafts centralized in emerging urban regions in Vietnam has accelerated the increase in the occurrence of diseases and threats to ecosystems induced by water pollution. We design a discrete choice experiment to elicit the willingness-to-pay of handicraft enterprises to restore the environment and diminish health risks from polluted wastewater through water quality improvement under different scenarios. Estimates from five latent classes reveal that one-half of entrepreneurs strongly value the provision of wastewater treatment services, and their decisions are mostly driven by preferences to reduce the risk of sickness caused by water pollution. This finding lends support to the argument that self-interested preferences predominate pro-environmental behavior in the readiness to pay for water quality services. While entrepreneurs' preferences attributed to ecological remediation seem to vary according to their educational background, the status-quo group shows low environmental awareness. This divergent behavioral pattern suggests that the design of wastewater management policies requires a mixture of measures that aim at different groups of individuals pursuing economic incentives and the creation of awareness.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Humanos , Vietnã , Águas Residuárias , Poluição da Água/prevenção & controle
5.
BMC Microbiol ; 22(1): 41, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35114945

RESUMO

BACKGROUND: Amoxicillin-resistant Helicobacter pylori (H. pylori) strains seem to have increased over time in Vietnam. This threatens the effectiveness of H. pylori eradication therapies with this antibiotic. This study aimed to investigate the prevalence of primary resistance of H. pylori to amoxicillin and to assess its association with pbp1A point mutations in Vietnamese patients. MATERIALS AND METHODS: Naive patients who presented with dyspepsia undergoing upper gastrointestinal endoscopy were recruited. Rapid urease tests and PCR assays were used to diagnose H. pylori infection. Amoxicillin susceptibility was examined by E-tests. Molecular detection of the mutant pbp1A gene conferring amoxicillin resistance was carried out by real-time PCR followed by direct sequencing of the PCR products. Phylogenetic analyses were performed using the Tamura-Nei genetic distance model and the neighbor-joining tree building method. RESULTS: There were 308 patients (46.1% men and 53.9% women, p = 0.190) with H. pylori infection. The mean age of the patients was 40.5 ± 11.4 years, ranging from 18 to 74 years old. The E-test was used to determine the susceptibility to amoxicillin (minimum inhibitory concentration (MIC) ≤ 0.125 µg/ml) in 101 isolates, among which the rate of primarily resistant strains to amoxicillin was 25.7%. Then, 270 sequences of pbp1A gene fragments were analysed. There were 77 amino acid substitution positions investigated, spanning amino acids 310-596, with the proportion varying from 0.4 to 100%. Seven amino acid changes were significantly different between amoxicillin-sensitive (AmoxS) and amoxicillin-resistant (AmoxR) samples, including Phe366 to Leu (p <  0.001), Ser414 to Arg (p <  0.001), Glu/Asn464-465 (p = 0.009), Val469 to Met (p = 0.021), Phe473 to Val (p <  0.001), Asp479 to Glu (p = 0.044), and Ser/Ala/Gly595-596 (p = 0.001). Phylogenetic analyses suggested that other molecular mechanisms might contribute to amoxicillin resistance in H. pylori in addition to the alterations in PBP1A. CONCLUSIONS: We reported the emergence of amoxicillin-resistant Helicobacter pylori strains in Vietnam and new mutations statistically associated with this antimicrobial resistance. Additional studies are necessary to identify the mechanisms contributing to this resistance in Vietnam.


Assuntos
Substituição de Aminoácidos/genética , Amoxicilina/farmacologia , Antibacterianos/farmacologia , Resistência a Medicamentos/genética , Helicobacter pylori/efeitos dos fármacos , Helicobacter pylori/genética , Proteínas de Ligação às Penicilinas/genética , Mutação Puntual/genética , Adolescente , Adulto , Idoso , Proteínas de Bactérias/genética , Feminino , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/patologia , Infecções por Helicobacter/epidemiologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Vietnã/epidemiologia , Adulto Jovem
6.
Anticancer Drugs ; 33(1): e720-e723, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34348357

RESUMO

Histological transformation into squamous cell carcinoma (SCC) is a rare mechanism of resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors. Its pathophysiology remains unclear and its management is particularly challenging. We report on tumor progression with SCC histological transformation associated with the T790M mutation in a patient with stage IV bronchial adenocarcinoma with an L858R mutation of the EGFR gene and treated with gefitinib. We will discuss the importance of liquid and tumor biopsy in the diagnostic management of resistance mechanisms as well as therapeutic management options.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Neoplasias Pulmonares/patologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Feminino , Gefitinibe/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/uso terapêutico
7.
Fish Physiol Biochem ; 48(4): 853-867, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35652992

RESUMO

Pituitary gonadotropins, metabolic hormones, and sex steroids are known factors affecting the advanced stages of ovarian development in teleost fish. However, the effects of these hormones and of the interactions between them on the growth of previtellogenic ovarian follicles are not known. In order to address this void in understanding, previtellogenic ovarian fragments from eel, Anguilla australis, were incubated in vitro with recombinant Japanese eel follicle-stimulating hormone (rec-Fsh), human chorionic gonadotropin (hCG), or 11-ketotestosterone (11-KT) in the presence or absence of recombinant human insulin-like growth factor-1 (IGF1). The results of long-term in vitro culture (21 days) demonstrated that rec-Fsh and 11-KT, rather than hCG, caused significant increases in the diameter of previtellogenic oocytes. Meanwhile, only 11-KT induced a significant increase in lipid accumulation. Moreover, a greater effect on oocyte growth was observed when IGF1 supplementation was combined with 11-KT rather than with rec-Fsh or hCG. For short-term culture (24 h), treatment with 11-KT in the presence or absence of IGF1 had no significant effects on mRNA levels of target genes (lhr, cyp19, cyp11b, lpl, and ldr) except for upregulation of fshr. There were no significant effects of rec-Fsh on expression of any target gene, whereas hCG downregulated the expression of these genes. There was no evidence for any interaction between the gonadotropins and IGF1 that resulted in growth of previtellogenic oocytes. Taken together, these results suggest that hormones from both the reproductive and the metabolic axes regulate the growth of previtellogenic oocytes in Anguilla australis.


Assuntos
Anguilla , Anguilla/genética , Animais , Gonadotropina Coriônica/farmacologia , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Expressão Gênica , Gonadotropinas/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Oócitos/metabolismo , Testosterona/análogos & derivados , Testosterona/metabolismo
8.
AIDS Behav ; 24(8): 2347-2354, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31970581

RESUMO

Stigma poses considerable challenges to the mental health of people living with HIV who use drugs (PLHWUD). In this study, we explored factors related to different types of stigma (perceived and internalized) attached to layered stigmatizing characters (HIV and drug use) and their mental health influences on PLHWUD. The study used baseline data of an ongoing randomized controlled trial among 241 PLHWUD recruited between March and December 2018 in Vietnam. A structural equation model was used to assess the relationships among different types and layers of stigma and mental health status. Both perceived and internalized drug-related stigma measures were significantly higher than their corresponding HIV-related stigma. HIV-related stigma was negatively associated with mental health status; however, we did not find a significant relationship between drug-related stigma and mental health. Tailored intervention strategies in consideration of types and layers of stigma are needed to address stigma-related challenges faced by PLHWUD.


Assuntos
Infecções por HIV , Transtornos Relacionados ao Uso de Substâncias , Adulto , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Saúde Mental , Pessoa de Meia-Idade , Estigma Social , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Vietnã/epidemiologia
9.
AIDS Care ; 32(sup2): 83-90, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32297556

RESUMO

HCV co-infection is widespread among people living with HIV who use drugs (PLHWUD). However, HCV testing was inconsistently implemented among PLHWUD. The low infection awareness and mental health challenges together impede PLHWUD's treatment-seeking. The study used baseline data of a randomized controlled trial conducted in Vietnam. HCV infection status was collected through self-report and medical record review. A linear mixed-effects regression model was used to examine the relationships between PLHWUD's perceived barriers to seeking healthcare, their depressive symptoms, and the consistencies in HCV status reports. Among the 181 PLHWUD in the study, one-third (64; 35.4%) had inconsistent self-reports and medical records of HIV infection status. The agreement between the two records was fair (Kappa statistics = 0.43). PLHWUD with consistent HCV infection confirmed by both medical records and self-reports perceived lower levels of healthcare-seeking barriers than those with discrepant HCV reports (estimated difference = -1.59, SE = 0.71, P = 0.027). Depressive symptoms were significantly correlated with healthcare-seeking barriers among those with discrepant HCV results (estimate = 0.17, SE = 0.06, P = 0.007). There is an urgent need to extend HCV screening efforts and increase HCV awareness among PLHWUD. Explicit HCV result notification and integrated mental health support are recommended to facilitate patients' access to needed care.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Infecções por HIV/complicações , Acessibilidade aos Serviços de Saúde , Hepatite C/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Coinfecção , Comorbidade , Estudos Transversais , Depressão , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Hepacivirus/isolamento & purificação , Hepatite C/psicologia , Humanos , Masculino , Programas de Rastreamento , Saúde Mental , Pessoa de Meia-Idade , Autorrelato , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Vietnã/epidemiologia
10.
Neural Comput ; 31(3): 555-573, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30645181

RESUMO

Redundancy is a fundamental characteristic of many biological processes such as those in the genetic, visual, muscular, and nervous systems, yet its driven mechanism has not been fully comprehended. Until recently, the only understanding of redundancy is as a mean to attain fault tolerance, which is reflected in the design of many man-made systems. On the contrary, our previous work on redundant sensing (RS) has demonstrated an example where redundancy can be engineered solely for enhancing accuracy and precision. The design was inspired by the binocular structure of human vision, which we believe may share a similar operation. In this letter, we present a unified theory describing how such utilization of redundancy is feasible through two complementary mechanisms: representational redundancy (RPR) and entangled redundancy (ETR). We also point out two additional examples where our new understanding of redundancy can be applied to justify a system's superior performance. One is the human musculoskeletal system (HMS), a biological instance, and the other is the deep residual neural network (ResNet), an artificial counterpart. We envision that our theory would provide a framework for the future development of bio-inspired redundant artificial systems, as well as assist studies of the fundamental mechanisms governing various biological processes.


Assuntos
Fenômenos Fisiológicos Musculoesqueléticos , Redes Neurais de Computação , Biomimética , Humanos , Modelos Biológicos
11.
Gen Comp Endocrinol ; 272: 83-92, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529311

RESUMO

Despite tremendous importance of follicle-stimulating hormone (Fsh) and luteinizing hormone (Lh) as primary controllers of reproductive development, information on the expression profiles of the genes encoding gonadotropin subunits and gonadotropin receptors (Fshr and Lhr) in wild eels are essentially non-existent. This study investigated pituitary fshb and lhb mRNA levels and ovarian fshr and lhr mRNA levels of wild shortfinned eels, Anguilla australis at different stages of oogenesis. Protein expression of Fsh in the pituitary was also quantified and visualized using slot blot and immunohistochemistry. Pituitary fshb and lhb mRNA levels showed a differential expression pattern, fshb mRNA levels increasing significantly from the perinucleolus (PN) to the oil droplet stage (OD) before slightly decreasing (not significantly) in the early vitellogenic stage (EV). A similar trend was observed in relative Fsh protein levels analyzed by slot blot and immunohistochemistry, but this trend was not reflected in the plasma levels of sex steroids. In contrast, pituitary lhb mRNA levels increased significantly from the PN to EV stage. A higher expression of Fsh at both mRNA and protein levels in the pituitary of eels at the OD stage compared to other investigated stages suggests that synthesis of Fsh production in the pituitary may reach a peak at the OD stage. In the ovary, transcript abundances of fshr and lhr gradually increased during previtellogenic follicle growth, but markedly and significantly increased thereafter. Taken together, our data suggest i) that Fsh release may be very limited, or absent, prior to onset of puberty in shortfinned eels and ii) that Lh is not functionally important in this fish during the EV stage.


Assuntos
Hormônio Foliculoestimulante/metabolismo , Gonadotropinas/metabolismo , Hormônio Luteinizante/metabolismo , Receptores da Gonadotropina/metabolismo , Anguilla/metabolismo , Animais , Feminino , Nova Zelândia , Maturidade Sexual
12.
Am J Dermatopathol ; 40(12): 917-919, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29933313

RESUMO

An 83-year-old man presented to the dermatology department for an ulcerated skin lesion of the back that had been increasing in size during the past 11 years. The physical examination revealed a well-defined, fleshy, reddish plaque measuring 10 × 20 cm in diameter with erosions and black areas on the surface. The patient underwent surgical excision with margins of 10 mm followed by a skin graft. Histologic section showed a lesion composed of 2 intimately intermingled epithelial and mesenchymal components associated with a basal cell carcinoma (BCC). Immunohistochemical examination showed epithelial cells that were positive for CK AE1/AE3 and p53, whereas stromal cells were positive for vimentin, CD10, and p53. BCC was positive for CD10. On the basis of these findings, a diagnosis of trichoblastic carcinosarcoma associated with BCC was made. Given the scarcity of data available in the literature regarding this diagnosis, no standard of care exists. No adjuvant treatment was provided and after 1 year of follow-up, the patient did not experience recurrence.


Assuntos
Carcinoma Basocelular/patologia , Carcinossarcoma/patologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Cutâneas/patologia , Idoso de 80 Anos ou mais , Humanos , Masculino
13.
Small ; 13(47)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29076647

RESUMO

Structure-property relationships of silk is an intriguing topic for silk-based biomaterials research since these features are related to biomimicking the processing in natural silk fiber formation which results in excellent mechanical properties. Strain-stiffening is common for spider silks and nonmulberry silkworm silks. However, the structural origin of strain-stiffening remains unclear. In this paper, the strain-dependent structural change of Antheraea pernyi silkworm silk is studied by X-ray fiber diffraction and Fourier transform infrared spectroscopy under stretching. Based on a combination of mechanical and structural analysis, the molecular origins of strain-stiffening in A. pernyi silk were determined. The relatively high content of the ß-sheets within the amorphous domains in A. pernyi silk is responsible for strain-stiffening, where "molecular spindles" enhance the extensibility and toughness of the fiber.

14.
BMC Pediatr ; 17(1): 104, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28403842

RESUMO

BACKGROUND: Stem cell therapy has emerged as a promising method for improving motor function of patients with cerebral palsy. The aim of this study is to assess the safety and effectiveness of autologous bone marrow mononuclear stem cell transplantation in patients with cerebral palsy related to oxygen deprivation. METHODS: An open label uncontrolled clinical trial was carried out at Vinmec International Hospital. The intervention consisted of two administrations of stem cells, the first at baseline and the second 3 months later. Improvement was monitored at 3 months and 6 months after the first administration of stem cells, using the Gross Motor Function Measure (GMFM) and Modified Ashworth Score which measures muscle tone. RESULTS: No severe complications were recorded during the study. After transplantation, 12 patients encountered fever without infections and 9 patients experienced vomiting which was easily managed with medications. Gross motor function was markedly improved 3 months or 6 months after stem cell transplantation than at baseline. The post-transplantation GMFM-88 total score, each of its domains and the GMFM-66 percentile were all significantly higher (p-value < 0.001). Muscle spasticity also reduced significantly after transplantation (p-value < 0.001). The therapy was equally effective regardless of sex, age and GMFCS level (p-value > 0.05). CONCLUSION: Autologous bone marrow mononuclear cell transplantation appears to be a safe and effective therapy for patients with cerebral palsy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02569775 . Retrospectively registered on October 15, 2015.


Assuntos
Transplante de Medula Óssea/métodos , Paralisia Cerebral/cirurgia , Transplante de Células-Tronco Hematopoéticas/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Transplante Autólogo , Resultado do Tratamento
15.
Acta Neuropathol ; 132(4): 625-34, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27573687

RESUMO

The new WHO classification of diffuse gliomas has been refined and now includes the 1p/19q codeletion, IDH1/2 mutation, and histone H3-K27M mutation. Our objective was to assess the prognostic value of the updated 2016 WHO classification in the French POLA cohort. All cases of high-grade oligodendroglial tumors sent for central pathological review and included into the French nationwide POLA cohort were reclassified according to the updated 4th WHO classification. In total, 1041 patients were included, with a median age at diagnosis of 50.4 years (range 17.1-84.4). Based on the new histomolecular classification, diagnoses included anaplastic oligodendroglioma IDH mutant and 1p/19q-codeleted (32.5 %), anaplastic astrocytoma IDH mutant (IDH (mut)) (11.0 %), anaplastic astrocytoma IDH wild type (IDH (wt)) (5.3 %), glioblastoma IDH (mut) (17.1 %), and glioblastoma IDH (wt) (33.2 %). Ten patients presented with a diffuse midline tumor, H3 K27M mutant. The new WHO classification was prognostic for progression-free survival (PFS) and overall survival (OS) (p < 0.001). We did not find prognosis differences between grades III and IV for IDH (mut) 1p/19q intact and IDH (wt) gliomas in univariate and multivariate analyses. Among anaplastic astrocytoma IDH (wt), cases with chromosome arm 7p gain and 10q loss (55 %) had shorter PFS than the others (p = 0.027). In conclusion, the new WHO histomolecular classification of diffuse gliomas presented with high prognostic value. Grading was not discriminant between grade III and IV high-grade gliomas.


Assuntos
Astrocitoma/epidemiologia , Neoplasias Encefálicas/epidemiologia , Glioma/epidemiologia , Oligodendroglioma/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/genética , Neoplasias Encefálicas/genética , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Glioma/classificação , Glioma/genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação/genética , Oligodendroglioma/genética , Prognóstico , Organização Mundial da Saúde , Adulto Jovem
16.
Ann Pathol ; 36(2): 130-3, 2016 Apr.
Artigo em Francês | MEDLINE | ID: mdl-26995102

RESUMO

The colloid milium has four clinical forms: adult colloid milium, juvenile colloid milium, paracolloid (or nodular colloid degeneration) and pigmented colloid milium. We report the case of an adult colloid milium in a man of 56, who presented episodes of diffuse pruritus associated with myalgia and digestive disorders, indicative of trichinosis. He also developed gradually over the past 10 years, yellowish injuries in the mandibles and neck for whom histology objectified a colloid milium. Etiology and treatment are still unknown; association with a trichinosis is probably coincidental.


Assuntos
Coloides/análise , Dermatoses Faciais/complicações , Ceratose/complicações , Triquinelose/complicações , Adulto , Diagnóstico Diferencial , Dermatoses Faciais/diagnóstico , Dermatoses Faciais/patologia , Humanos , Ceratose/diagnóstico , Ceratose/patologia , Masculino , Prurido/etiologia , Triquinelose/diagnóstico
17.
Small ; 11(9-10): 1039-54, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25510895

RESUMO

This review provides a comprehensive survey of the structural characteristics of crystal networks of silk soft fibrous materials in correlation with the macroscopic properties/performance and the network formation mechanisms. The correlation between the hierarchical mesoscopic structures and the mechanical properties of silk soft fibrous materials including silk fibroin hydrogels and naturally spun silk fibers are addressed based on the hierarchical crystal network models. Namely, two types of hierarchical networks are identified: the weak nanofibril-nanofibril interaction case (i.e., silk fibroin hydrogels), and the strong nanofibril-nanofibril interaction case (i.e., silk fibers). The macroscopic properties, i.e., the rheological/mechanical properties, can be controlled in terms of tuning different levels of hierarchical network structures by ultrasonication-induced gelation, introducing the initial nucleation centers, etc. Such controls take effect by different mesoscale assembly pathways, which are found to occur via different routes of the nucleation and growth processes. Furthermore, the hierarchical network model of soft fibrous materials can be applied to explain the superior mechanical properties and the unique strain-hardening behaviors of spider silk fibers within the framework of hierarchical breaking mechanism. Obviously, a knowledge of crystal networks will allow the prediction of the performance and engineering strategy of silk fibrous materials in generals.


Assuntos
Fibroínas/química , Teste de Materiais , Nanofibras/química , Nanotecnologia/métodos , Engenharia de Proteínas/métodos , Animais , Bombyx , Simulação por Computador , Cristalização , Hidrogéis/química , Microscopia Eletrônica de Varredura , Estrutura Secundária de Proteína , Reologia , Aranhas , Estresse Mecânico
18.
J Chem Phys ; 140(4): 044101, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25669499

RESUMO

We develop a method that combines data mining and first principles calculation to guide the designing of distorted cubane Mn(4+)Mn3(3+) single molecule magnets. The essential idea of the method is a process consisting of sparse regressions and cross-validation for analyzing calculated data of the materials. The method allows us to demonstrate that the exchange coupling between Mn(4+) and Mn(3+) ions can be predicted from the electronegativities of constituent ligands and the structural features of the molecule by a linear regression model with high accuracy. The relations between the structural features and magnetic properties of the materials are quantitatively and consistently evaluated and presented by a graph. We also discuss the properties of the materials and guide the material design basing on the obtained results.

19.
IEEE Trans Biomed Circuits Syst ; 18(2): 274-287, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37782620

RESUMO

This article presents a high precision, wide dynamic range (DR) closed-loop neuromodulation (CLNM) system that can completely reject stimulation artifacts (SA) and achieve rapid SA recovery. In the recorder, a novel SA quick-blanking scheme is proposed for rail-to-rail SA rejection while minimizing SA recovery time. Besides, a new analog front-end (AFE) architecture based on a frequency-shaping (FS) technique is developed to extend DR intrinsically. In the stimulator, a stimulation driver implemented with a proposed redundant crossfire (RXF) technique is incorporated to improve the effective resolution of the stimulation current. The designed CLNM system is implemented in a 180 nm Bipolar-CMOS-DMOS (BCD) process. Measurement results show that the system is capable of tolerating rail-to-rail (5 V) SA and reducing the SA recovery time from 12 ms to 0.15 ms. The FS recorder extends the DR at low frequencies (LF) to 17.5 bits to enhance tolerance to LF interferences. The proposed stimulator adopting the 4-way RXF topology improves the effective resolution to 12.75 bits without consuming much extra area and power. Animal experiments demonstrate that the designed system can acquire high-fidelity neural signals immediately after stimulation onsets, thus supporting concurrent recording and stimulation.


Assuntos
Artefatos , Animais
20.
IEEE Trans Biomed Circuits Syst ; 18(1): 160-173, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37747860

RESUMO

Concurrent recording of neural activities and functional magnetic resonance imaging (fMRI) data is useful for studying the neurovascular coupling relationship. This article presents a low-noise, frequency-shaping based neural recorder chip that is insensitive to radio frequency (RF) pulses and gradient echo artifacts under strong magnetic environment. To support simultaneous recording of local field potentials (LFPs), extracellular spikes, and fMRI data, a magnetic resonance imaging (MRI) compatible data acquisition (DAQ) device based on the designed recorder chip is developed with multiple circuit optimization techniques. Bench-top measurement shows that the designed DAQ device has 4.5 µV input-referred noise integrated from 300 Hz to 3000 Hz, which is not greatly affected by electromagnetic interference (EMI) at ultrahigh magnetic field (UMF, 16.4 T). In animal experiments, the designed DAQ device has been demonstrated to be capable of acquiring both the LFPs and extracellular spikes from a rat's brain before, during, and after MRI scanning. Besides, no obvious artifacts are seen from the designed DAQ device at multiple typical MRI scanning modes, and the system recovery time after gradient artifacts is reduced from more than 25 ms to less than 5 ms. The proposed DAQ device architecture based on the frequency-shaping neural recorder chip is MRI compatible and can provide highly competitive performance for concurrent recording of neural activities and fMRI data.


Assuntos
Benzoquinonas , Campos Magnéticos , Imãs , Animais , Ratos , Imageamento por Ressonância Magnética/métodos , Artefatos , Encéfalo/diagnóstico por imagem
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