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1.
Iran J Vet Res ; 24(1): 30-36, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378387

RESUMO

Background: The major challenge of foot-and-mouth disease (FMD) control is attributed to the rapid mutations in the FMDV RNA genome, resulting in continuous antigenic changes of circulating strains. Despite widespread vaccination of livestock populations, the incidence of the FMDV serotype O outbreaks in Iran during 2015-2016 raised concerns about the emergence of new strains. Aims: The aim of this study is the genetic and antigenic evaluation of FMDV type O isolates from different outbreak areas including Alborz, Tehran, Isfahan, Markazi, Zahedan, and Qom provinces. Methods: For this purpose, 71 FMD-infected samples were collected from six provinces of Iran, of which 12 serotype O positive were selected for genetic analysis. Results: All samples were in ME-SA topotypes/OPanAsia2 lineage, and the overall mean of genetic diversities at the 1D gene level was about 5% between the sequences. Blasting 1D gene sequences of isolated viruses showed more than 90% genetic identity with sequences registered from neighboring countries; therefore, it could be concluded that they had a common origin. Six isolates showed the highest genetic diversity (6% to 11%) with the OPanAsia2 vaccine strain (JN676146), which three of them (Qom, Alborz, and Zahedan isolates), had less than 30% antigenic homology with the OPanAsia2 virus (JN676146). Conclusion: Results of this study suggested OPanAsia2 vaccine had no enough coverage with some circulating strains in outbreak areas in Qom, Alborz, and Zahedan provinces, and the necessity of OPanAsia2 replacement with a new vaccine strain in Iran.

2.
J Microbiol Methods ; 208: 106720, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37031896

RESUMO

Vat dyes are the most commonly used dyes in the denim industry. Since the pollution of the textile industry is a worldwide problem, Aspergillus niger was used in this study, to treat vat dye wastewater by pre-culture and simultaneous-culture methods. A comparison between the two biosorption techniques used showed that pre-culture was about 30% more efficient than simultaneous culture. The adsorption capacity was determined using the Langmuir and Freundlich adsorption models, with Langmuir proving to be the most suitable model. The high saturation capacity of 121.35 mg/g for C.I. Vat Brown 1 calculated with the Langmuir adsorption model indicated that A.niger is a suitable sorbent for vat dye wastewater. To investigate the influence of dye structure on biosorption efficiency, eight vat dyes with different chemical characteristics were used. The results showed that the complete decolorization time was reduced by 200 and 150 min for planar and non-planar structures, respectively, due to the reduction of molecular mass, indicating that molecular mass is probably the dominant factor in vat dye removal. In addition, planar structures resulted in a 50-min reduction in biosorption time. The possible adsorption sites were analyzed by Fourier transfer infrared analysis. The results showed that the amino and carboxyl groups of the fungus could serve as sorption sites for vat dyes through hydrogen bonding."


Assuntos
Aspergillus niger , Poluentes Químicos da Água , Águas Residuárias , Estrutura Molecular , Corantes/análise , Biomassa , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de Hidrogênio , Cinética
3.
Arch Razi Inst ; 78(6): 1843-1851, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38828163

RESUMO

Foot-and-mouth disease (FMD) has a high prevalence in cloven-hoofed animals. It is also highly contagious and remains a serious threat to livestock worldwide. Despite the widespread vaccination program in Iran, outbreaks of FMD continue to occur. Vaccination is one of the most effective methods of preventing FMD. The vaccines used in Iran are of the inactivated type and contain several serotypes. Since inactivated vaccines without adjuvants do not induce a high and durable antibody response, it is necessary to use adjuvants. Montanide ISA 206 VG is a mineral oil-based adjuvant that produces a water-in-oil-in-water (w:o:w) emulsion in vaccine preparations. However, a large number of manufacturers in Iran and around the world still use alum adjuvant (with or without saponin) to produce the FMD vaccine. This study used Montanide ISA 206 and alum adjuvants to administer the O2010 serotype of the FMD virus to goats. A total of six goats were divided randomly into three groups. Vaccines were administered subcutaneously twice, at a one-month interval. Blood sampling was done at different times, and the micro-neutralization method was used to measure the neutralizing antibody titer in each serum. Seven days after the second vaccination, the alum group's antibody titer was higher but not statistically significant. However, from the 28th day after the second injection until the end of the study, the Montanide ISA 206 group's antibody titer was significantly higher than that of the alum group. Six months after the second injection, the antibody titer in the ISA 206 group remained at the peak level, while in the alum group, it decreased and reached the minimum protective level. Nine months after the second injection, the antibody titer remained at its peak level in the ISA 206 group, whereas it dropped significantly in the alum group. Based on the findings, ISA 206 VG is capable of generating long-term humoral immunity in goats against the FMD serotype O2010 and could replace aluminum hydroxide adjuvants in FMD vaccine preparations.


Assuntos
Adjuvantes Imunológicos , Hidróxido de Alumínio , Anticorpos Neutralizantes , Vírus da Febre Aftosa , Febre Aftosa , Doenças das Cabras , Cabras , Vacinas Virais , Animais , Hidróxido de Alumínio/administração & dosagem , Hidróxido de Alumínio/farmacologia , Vírus da Febre Aftosa/imunologia , Doenças das Cabras/prevenção & controle , Febre Aftosa/prevenção & controle , Febre Aftosa/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Irã (Geográfico) , Ácidos Oleicos/administração & dosagem , Manitol/análogos & derivados , Manitol/administração & dosagem
4.
Aust Dent J ; 67(4): 328-339, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35718919

RESUMO

BACKGROUND: This population-based cohort study investigated dental procedures in the hospital setting in Western Australian children with or without intellectual disability (ID) and/or autism spectrum disorder (ASD) aged up to 18 years. Considering previously reported disparities in dental disease between Indigenous and non-Indigenous Australian children, this study also investigated the effect of Indigenous status on dental procedures. METHODS: Data on Western Australian live births from 1983 to 2010 from the Midwives Notification System were linked to the Intellectual Disability Exploring Answers database and the Hospital Morbidity Data collection. Primary admissions for relevant dental diagnoses were identified, and treatment procedures for dental hospitalization were investigated. Descriptive statistics and Pearson's chi-squared test of independence were used for analysis. RESULTS: Overall, 76 065 episodes of dental hospitalization were recorded. Amongst children with ID and/or ASD, Indigenous children experienced more extractions and fewer restorations (68.7% and 16.2%) compared to non-Indigenous children (51.5% and 25.9%). After 6 years, extraction occurred less often in children with ID and/or ASD than in those without, where most surgical dental extractions were in the age group of 13-18 years. CONCLUSIONS: This study indicates a need for further improvements in access to dental services and the quality of care provided in hospitals for children with ID/ASD. There is also concern that more vulnerable Indigenous and all disadvantaged children are receiving an inadequate level of dental services resulting in more emergency dental hospitalization and invasive treatment.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Criança , Humanos , Idoso , Adolescente , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/epidemiologia , Deficiência Intelectual/complicações , Deficiência Intelectual/epidemiologia , Estudos de Coortes , Austrália , Hospitais , Odontologia
5.
Trials ; 22(1): 349, 2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011413

RESUMO

OBJECTIVES: In this study, we will investigate the effect of hydroxychloroquine on the prevention of novel coronavirus disease (COVID-19) in cancer patients being treated. TRIAL DESIGN: This is a two-arm, parallel-group, triple-blind, phase 2-3 randomized controlled trial. PARTICIPANTS: All patients over the age of 15 years from 5 types of cancer will be included in the study. Patients with acute lymphoid and myeloid leukemias in the first line treated with curative intent, patients with high-grade non-Hodgkin's lymphoma treated with leukemia regimens, and patients with non-metastatic breast and colon cancer in the first line of treatment will enter the study. INTERVENTION AND COMPARATOR: Patients are randomly assigned to two groups: one being given hydroxychloroquine and the other is given placebo. During 2 months of treatment, the two groups will be treated with hydroxychloroquine every other day with a single 200-mg tablet (Amin® Pharmaceutical Company, Isfahan, Iran) or placebo (identical in terms of shape, color, and smell). Patients will be monitored for COVID-19 symptoms during follow-up period. If any COVID-19-related signs or symptoms occur, they will be examined, thoroughly, investigated with a high resolution computerize tomography (CT) scan of the lungs and nasopharyngeal swab assessed by RT-PCR for SARS-CoV-2 virus. This study will be performed in five centers affiliated to Mashhad University of Medical Sciences, Mashhad, Iran. MAIN OUTCOMES: The primary end point of this study is to investigate the incidence of COVID-19 in patients being treated for their cancer and receiving prophylactic Hydroxychloroquine. RANDOMIZATION: Randomization will be performed using random permuted blocks. By using online website ( www.randomization.com ), the randomization sequence will be produced by quadruple blocks. The allocation ratio in intervention and control groups is 1:1. BLINDING (MASKING): Participants and caregivers do not know whether the patient is in the intervention or the control group. Those assessing the outcomes and data analyzer are also blinded to group assignment. SAMPLE SIZE: The calculated total sample size is 60 patients, with 30 patients in each group.


Assuntos
Tratamento Farmacológico da COVID-19 , Neoplasias , Adolescente , Humanos , Hidroxicloroquina/efeitos adversos , Irã (Geográfico) , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento
6.
Arch Razi Inst ; 75(3): 349-357, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33025775

RESUMO

The foot-and-mouth disease virus (FMDV) with a wide variety of genomes and complicated biology is one of the infectious agents that put the lives of animals at risk. Therefore, to introduce suitable strains for vaccine production, it is essential to constantly evaluate genetic changes of circulating viruses in field. Within 2014-2015, a total of 126 clinical specimens consisting of epithelial tissue and vesicular fluid from tongue, dental pad, and hoofs suspected of FMD virus were submitted to the Reference Laboratory for FMD in Razi Vaccine and Serum Research Institute, and 86 of them were identified as FMD virus type A using sandwich Enzyme-Linked Immunosorbent Assay (ELISA). This virus was isolated from 42 samples from 16 provinces using cell culture. Firstly, the coding region that produces the main part of viral capsid was amplified by Polymerase chain reaction (PCR). This part of the genome by 800 bp length was related to the 1D gene that synthesizes the VP1 protein. The phylogenetic analysis of VP1 coding region determined two distinct genotypes with more than 15% nucleotide differences. The first cluster consisted of closely related viruses registered in the GeneBank of neighboring countries, including Afghanistan, Pakistan, and Turkey. All samples in Cluster1 were determined as relative viruses with genotype Iran-05. In-vitro serological examination indicated an antigenic relationship between Cluster 1 viruses and routine vaccine strain (A-IRN-2013). The second cluster with only two members was genetically far from earlier ones and could be considered a separate genotype. Furthermore, it was revealed that cluster 2 has not been previously reported in Iran. Genetic tracing indicated that these viruses might have been originated from circulating viruses from India. Antigenic evaluation exhibited that this group could not be cross-protected by the routine vaccinal strain (A-IRN-2013) used during the research period.


Assuntos
Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/imunologia , Febre Aftosa/virologia , Doenças das Cabras/virologia , Doenças dos Ovinos/virologia , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Febre Aftosa/classificação , Genótipo , Cabras , Irã (Geográfico) , Filogenia , Ovinos , Carneiro Doméstico
7.
J Cosmet Laser Ther ; 22(3): 126-127, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32506979

RESUMO

Fox-Fordyce disease (FFD) is an uncommon apocrine disorder. We reported a 26-year-old woman with bilateral axillary pruritic papular lesions following 2 sessions of treatment with Diode (800 nm) laser for axillary hair removal. No lesions were developed in the other treated areas. Topical 0.1% tacrolimus gel was used for her treatment.


Assuntos
Doença de Fox-Fordyce , Remoção de Cabelo , Terapia a Laser , Terapia com Luz de Baixa Intensidade , Adulto , Axila , Feminino , Doença de Fox-Fordyce/etiologia , Remoção de Cabelo/efeitos adversos , Humanos , Terapia a Laser/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos
8.
J Appl Microbiol ; 126(1): 332-343, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30099824

RESUMO

AIMS: The purpose of this work is to present and evaluate the performance of a novel Automatic Lab-in-vial Escherichia coli Remote Tracking technology based on an automated real-time defined substrate approach, implemented in both portable and in situ instruments. METHODS AND RESULTS: We present the fresh water calibration procedure, and assess performance using side-by-side comparison with most probable number (MPN) approaches in terms of accuracy, reproducibility and capability to correctly generate early-warning alerts. Long-term data from an operational in situ deployment at a potential bathing site is presented as well. CONCLUSIONS: Automatic Lab-in-vial Escherichia coli Remote Tracking technology is shown to be an accurate and rapid bacterial quantification technology, capable of autonomous in situ measurements with metrological capabilities comparable to those of an approved laboratory using MPN microplate techniques. SIGNIFICANCE AND IMPACT OF THE STUDY: Rapid quantification of bacterial pollution is a requirement in water quality applications ranging from recreational water use, agriculture and aquaculture to drinking and wastewater treatment. The method and instruments presented in this work should enable fast and accurate bacterial concentration measurements to be performed in a portable or in situ manner, thus simplifying operational logistics, reducing time-to-result delays, and eliminating sample transportation constraints associated with traditional techniques.


Assuntos
Automação Laboratorial/métodos , Monitoramento Ambiental/métodos , Escherichia coli/isolamento & purificação , Água Doce/microbiologia , Qualidade da Água , Reprodutibilidade dos Testes
9.
J Contam Hydrol ; 220: 6-17, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30471981

RESUMO

Drought is one of the most significant natural phenomena affecting different aspects of human life and the environment. Due to water scarcity, prediction of water quality reduction is very crucial for urban and rural communities. This study contributes by applying artificial neural network and modified fuzzy clustering techniques to estimate the drops in potential drinking water quality in the GIS environment. In this research, the probability of occurrence of adverse annual changes in the water quality of drinking water is estimated. The model was tested using real instances of the southeast aquifers, the regions of the central parts of the IRAN and especially the significant portions of the aquifers of the east area. To validate the model, the data adequacy test and the standardization of the drought index are used. The results of the lowest available water quality and the highest drought using ANNs show that the qualitative stress conditions in large part of the country's aquifers are in unfavorable conditions. Evidence from this research shows that the aquifers in these areas are expected to have severe drought stress and poor quality class status. Also, the computational results indicate that the modified clustering method increases the efficiency of the prediction model as against the previous research. The outcomes do not show a relatively favorable state of drinking water quality for some aquifers in the country. However, the conditions for quantitative changes in the depth of water, based on the predicted results of ANN, are considered critical. The generated maps demonstrate that about 64% of the study area is subjected to a severe deterioration in the quality of drinking water if the current trend continues in the exploitation of aquifers. As a result, the main finding the present study is that the probability of groundwater quality decline is significant in many aquifers in the country.


Assuntos
Água Potável , Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Humanos , Redes Neurais de Computação , Qualidade da Água
10.
Autoimmune Dis ; 2018: 4608490, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30410794

RESUMO

BACKGROUND: Psoriatic arthritis (PsA) results in an increased burden of psoriasis and impairs both quality of life and an individual's functional capacity. The relationship between nail involvement and PsA in psoriasis is not fully characterized. AIM: To evaluate the frequency and characteristics of nail involvement in psoriatic patients and to assess the relationship with joint involvement. METHODS: A total of 197 patients with moderate-to-severe psoriasis were consecutively invited to participate in this cross-sectional study. The patients are divided into two groups: those with and those without psoriatic arthritis. RESULTS: 69.5% of psoriatic (137 out of 197) patients had nail involvement. The most common nail abnormality was onycholysis, followed by pitting and oil droplet changes. Nail involvement was more common in patients with psoriatic arthritis (82.1% versus 57.8%, p=0.001). CONCLUSION: Nail involvement is commonly associated with PsA. Onycholysis, splinter hemorrhage, and oil drop were significantly more common in the PsA group as opposed to patients with just skin findings. In general, psoriatic patients with arthritis had more severe disease.

11.
Br J Oral Maxillofac Surg ; 56(4): 304-309, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29599049

RESUMO

Our aim was to assess the association between different components of sociodemographic status and the risk of developing squamous cell carcinoma (SCC) of the head and neck after we had adjusted for the influence of the known behavioural risk factors of smoking and drinking alcohol. We selected 146 patients with histopathologically-confirmed SCC of the head and neck, and matched them for age and sex with 266 healthy controls for this case-control study. Personal details, occupation, socioeconomic status, smoking, and alcohol consumption were recorded. The association of sociodemographic variables with oral cancer was evaluated both separately and with a composite socioeconomic index. Chi squared tests, adjusted odds ratios (OR), and 95% CI were computed using logistic regression to estimate the effect. There was a significant difference between the two groups in the composite socioeconomic index (p<0.001). The group with "low" socioeconomic status had the highest risk of oral cancer (OR=3.89, 95% CI 1.28 to 11.82). Better-educated people with higher incomes had a lower risk of SCC of the head and neck after we had controlled for behavioural risk factors. However, marital and employment status and place of residence were not significantly associated with risk. Our findings confirm that some socioeconomic determinants were associated with the development of oral cancer in this study group.


Assuntos
Carcinoma de Células Escamosas/etiologia , Neoplasias de Cabeça e Pescoço/etiologia , Determinantes Sociais da Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma de Células Escamosas/economia , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Escolaridade , Feminino , Neoplasias de Cabeça e Pescoço/economia , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Renda/estatística & dados numéricos , Irã (Geográfico)/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/efeitos adversos , Fatores Socioeconômicos , Adulto Jovem
12.
Int J Womens Dermatol ; 4(4): 230-235, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30627623

RESUMO

BACKGROUND: Isolated distant cutaneous metastasis of breast carcinoma is uncommon. Furthermore, isolated metastasis of the scalp seems to be very rare in breast cancer. CASE PRESENTATION: A 44-year-old woman was referred to our dermatology department with concerns of a firm, painless, immobile, hardened, skin-colored mass fixed to the underlying tissues. The lesion measured 2 to 3 cm on the scalp frontalis without regional or distant lymphadenopathy. The patient had a history of benign right breast biopsy test results.Immunohistochemistry test results were positive for cytokeratin (AE1/AE3), cytokeratin 7, chromogranin, estrogen receptor, and gross cystic disease fluid protein-15; group PR/HER2 were both weakly positive. Cytokeratin 20, thyroid-lung transcription factor, S100 protein, vimentin and thyroglobulin were all negative. Pathology test results showed adenocarcinoma that was consistent with breast primary. CONCLUSION: Although cutaneous metastasis of the chest wall due to breast carcinoma is a common condition, scalp metastasis as the first sign of occult breast cancer is an extremely rare condition. We describe an isolated scalp metastasis as the initial presentation of breast cancer in a young woman in this report, which highlights that health care providers should be alert to the possibility that atypical soft tissue masses may represent a neoplasm. Further consideration of the scalp lesions among healthy looking patients is recommended.

13.
Arch Razi Inst ; 73(4): 287-294, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-31077118

RESUMO

Venomous snakebite is a life-threatening injury in many tropical and subtropical areas including Iran. The gold standard treatment option for human envenomation is the use of antivenoms. Despite the unique effects of horse-derived antivenoms on the treatment of snakebite, they are not fully perfect and need improvements. In this study, human recombinant Fab fragment antivenom was produced in Rosetta-g bacterium using a gene library constructed in the previous study. The prepared Fab was purified in several steps, desalted, and lipopolysaccharide-depleted using ammonium sulfate solution and dialysis against phosphate buffer and Triton X-114 solution, respectively. Subsequently, the product was initially confirmed by the sodium dodecyl sulfate polyacrylamide gel electrophoresis and enzyme-linked immunosorbent assay (ELISA), respectively. Finally, the neutralization potency of the product was investigated in laboratory Syrian Mice. The obtained results showed corresponding reduced bands to Fab fragment with the molecular weight of about 28 kDa at a concentration of 3.1 mg/ml. There was a significant difference between the groups in terms of ELISA test (P&lt;0.05). The neutralization potency of the product against the venom of Echis carinatus (E. carinatus) was about 7 LD50/ml (54.6 &micro;g/ml) when tested on mice. Based on the results, the Fab fragment antivenom had the ability to neutralize the in vivo biological activity of the venom of Iranian E. carinatus. However, further studies are recommended to reach a suitable concentration of antivenom fragment.


Assuntos
Antivenenos/imunologia , Fragmentos Fab das Imunoglobulinas/imunologia , Venenos de Víboras/imunologia , Animais , Humanos , Proteínas Recombinantes/imunologia , Viperidae
14.
Eur Arch Paediatr Dent ; 18(6): 419-422, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29139037

RESUMO

AIM: To investigate the prevalence of oral lichen planus in patients younger than 18 years, referred to a dermatology centre in Iran during 2002-2014. Lichen planus is a chronic inflammatory, immune-mediated disease that could affect the oral mucosa and is a pre-cancerous condition. The disease usually develops in middle age with female predominance and is rare in children. METHODS: In this retrospective study, cases with definitive histopathologic diagnosis of lichen planus, over a 12-year period from 2002 to 2014 from a dermatologic hospital archive were evaluated. The prevalence of both cutaneous and oral lichen planus, the male:female ratio and site of involvement were calculated using SPSS version 21. RESULTS: Thirty-six of 564 patients younger than 18 years old diagnosed with lichen planus. Two females (0.4%) had oral lichen planus. One patient had erosive, and one had bullous, oral lichen planus. CONCLUSION: Oral lichen planus had a very low frequency in Iranian population younger than 18 years old, identifying these patients is recommended for long-term follow-up.


Assuntos
Líquen Plano Bucal/epidemiologia , Adolescente , Criança , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos , Distribuição por Sexo
15.
Nanotechnology ; 25(44): 445301, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25302579

RESUMO

We have developed a process to fabricate low-stress, fully crystalline silicon nanostencils, based on ion irradiation and the electrochemical anodization of p-type silicon. These nanostencils can be patterned with arbitrary feature shapes with openings hundreds of micrometers wide connected to long channels of less than 100 nm in width. These nanostencils have been used to deposit (2.5 µm- to 150 nm-wide) lines of LaAlO3 (LAO) on a SrTiO3 (STO) substrate, forming a confined electron layer at the interface arising from oxygen vacancies on the STO surface. Electrical characterization of the transport properties of the resulting LAO/STO nanowires exhibited a large electric field effect through back-gating using the STO as the dielectric, demonstrating electron confinement. Stencil lithography incorporating multiple feature sizes in a single mask shows great potential for future development of oxide electronics.

16.
Nanotechnology ; 25(37): 375301, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25148117

RESUMO

A method for single-step fabrication of arbitrary, complex, three-dimensional (3D) silicon structures from the nano- to millimeter-scale at multiple levels on non-planar, curved, or domed surfaces is reported. The fabrication is based on focused or masked ion beam irradiation of p-type silicon followed by electrochemical anodization. The process allows fabrication of a wide range of surface features at multiple heights and with arbitrary orientations by varying the irradiated feature width, ion type, energy fluence, and subsequent anodization conditions. The technology has achieved depth resolution of 10 nm as step heights and is capable of creating lateral features down to 7 nm at high aspect ratios of up to 40, with surface roughness down to 1 nm scaled up to full wafer areas. The single-step ability has seamlessly interfaced a network of complex, integrated micro- to nano-structures in 3D orientations with no alignment required. The final template has been converted to a master copy for nano-imprinting lithography of 3D fluidic structures and optical components.

17.
Int Endod J ; 47(9): 873-81, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24330490

RESUMO

AIM: This randomized clinical trial evaluated clinical sign/symptoms as well as histological pulp reactions in terms of inflammation and mineralized bridge formation after partial pulpotomy of sound human premolars and placement of a bioceramic paste (iRoot BP) or tooth-colored ProRoot MTA as pulp-covering biomaterials. METHODOLOGY: Twenty-four human sound premolars were randomly allocated into two experimental groups (n = 12) treated either with iRoot BP or MTA subsequent to partial pulpotomy. Six weeks after treatment, clinical sign/symptoms and radiographic changes were evaluated. The teeth were then extracted and examined histologically for inflammatory status of the pulp, formation of hard tissue bridge and appearance of the bridge. In terms of pulp inflammation and dentinal bridge formation, the Mann-Whitney U, and for clinical signs, the chi-square test was used (α = 0.05). RESULTS: In terms of pulp inflammation, formation of hard tissue bridge and its appearance, the differences between the two experimental groups were not significant. However, clinical sensitivity to cold was significantly less for teeth treated with MTA (P < 0.05). All cases had formed a hard tissue bridge, and none of the specimens in either group had pulpal necrosis. CONCLUSION: When treating teeth with healthy pulps, the response to partial pulpotomy treatment with both MTA and iRoot BP was favourable. However, pulps covered with iRoot BP were more sensitive to cold stimuli.


Assuntos
Dente Pré-Molar/cirurgia , Cerâmica , Polpa Dentária/efeitos dos fármacos , Pulpotomia/métodos , Humanos
18.
Biomed Microdevices ; 16(2): 229-36, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24305875

RESUMO

Geometric micro-patterned surfaces of silicon combined with porous silicon (Si/PSi) have been manufactured to study the behaviour of human Mesenchymal Stem Cells (hMSCs). These micro-patterns consist of regular silicon hexagons surrounded by spaced columns of silicon equilateral triangles separated by PSi. The results show that, at an early culture stage, the hMSCs resemble quiescent cells on the central hexagons with centered nuclei and actin/ß-catenin and a microtubules network denoting cell adhesion. After 2 days, hMSCs adapted their morphology and cytoskeleton proteins from cell-cell dominant interactions at the center of the hexagonal surface. This was followed by an intermediate zone with some external actin fibres/ß-catenin interactions and an outer zone where the dominant interactions are cell-silicon. Cells move into silicon columns to divide, migrate and communicate. Furthermore, results show that Runx2 and vitamin D receptors, both specific transcription factors for skeleton-derived cells, are expressed in cells grown on micropatterned silicon under all observed circumstances. On the other hand, non-phenotypic alterations are under cell growth and migration on Si/PSi substrates. The former consideration strongly supports the use of micro-patterned silicon surfaces to address pending questions about the mechanisms of human bone biogenesis/pathogenesis and the study of bone scaffolds.


Assuntos
Técnicas de Cultura de Células/métodos , Reprogramação Celular , Células-Tronco Mesenquimais/metabolismo , Silício/química , Técnicas de Cultura de Células/instrumentação , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Porosidade , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo
19.
J Nanosci Nanotechnol ; 12(11): 8666-70, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23421262

RESUMO

Branched carbon nanostructures have been successfully grown on interdigital comb-like structures for a gas sensing application. Field emission scanning electron microscopy has been utilized to investigate the morphology and structure of the grown nanostructures at different stages of growth process. Tunneling current of the fabricated sensor has been measured when a monotonically increasing voltage is applied between the electrodes. The effect of exposure to three different gases on the measured current has been studied. A data processing on the measured current voltage characteristics results in the evolution of various peaks at distinct voltages which depends on the type of the gas.


Assuntos
Condutometria/instrumentação , Gases/análise , Gases/química , Nanotecnologia/instrumentação , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Desenho de Equipamento , Análise de Falha de Equipamento
20.
Int Psychiatry ; 9(3): 55-57, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31508123

RESUMO

Mental health and psychiatric services in Afghanistan have gone through various stages of development and crisis but the long-term impact of recent wars and conflict on the country's mental health services has not been evaluated. What is obvious is the shortage of trained mental health professionals in the country.

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