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1.
Biol Futur ; 72(4): 441-452, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34554490

RESUMO

A population of 105 wheat genotypes (including 94 hexaploid and 11 tetraploid genotypes) was used to determine genetic diversity. Samples were grown based on the randomized complete block design with three replications under salinity stress (120 mM NaCl (and control (10 mM NaCl (conditions. Morpho-physiological traits associated with tolerance of salinity at the seedling stage were recorded. The results of the analysis of variance showed that there were significant differences between genotypes in all studied traits, except K+/Na+ ratio. The amount of potassium content of leaves and roots in control was higher than salt stress conditions. Salinity significantly decreased all traits measured except Na+ concentration in root and shoot and leaf stomata conduction. A total of 12 SSR (simple sequence repeats) markers were assessed for the existence of polymorphism between genotypes. The highest Nei (Nei 1973) gene diversity was observed for gwm410 (0.72) and gpw2181 (0.71) markers, and PIC (polymorphic information content index) values ranged from 0.2 to 0.67. According to PIC, only six markers were informative during this study. These markers could be more efficient in displaying the genotypic differentiation of the near-wheat species as they showed the highest genetic diversity. Simple regression analysis showed that barc212 marker had the most significant relationship with root dry weight, leaf moisture and stomatal conductance (at 0.01 significant level). The gpw2181 marker showed a significant correlation with different traits under stress conditions. It was suggested that this marker could be used for marker-assisted selection to improve salt stress tolerance of wheat.


Assuntos
Variação Genética/fisiologia , Repetições de Microssatélites/genética , Triticum/genética , Variação Genética/genética , Irã (Geográfico) , Reação em Cadeia da Polimerase/métodos
2.
Nanotechnology ; 31(18): 185302, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31958783

RESUMO

We report and detail a lithography-free method to pattern Si substrates. In particular, a focused Ga ion beam is used to create regular patterns of holes which serve as a template for the growth of vertically aligned GaAs nanowires (NW)s on Si(111) substrates using self-catalyzed molecular beam epitaxy. We show that the hole diameter plays a crucial role in the growth of the NWs at the drilled holes. The critical parameters defining the width of the holes are: ion dose quantities, wet etching procedures, and high-temperature steps at the process of growth. As a result, we obtained a yield of more than 80% for vertically aligned NW. Compared to other methods of patterning our approach provides the following advantages: (i) it is a lithography-free procedure, (ii) allows for quick patterning process and hole diameter optimization within a small window of trial and error, (iii) and provides potential applicability for different material systems.

3.
J Clin Exp Dent ; 9(1): e107-e111, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28149473

RESUMO

BACKGROUND: Class II malocclusion is one of the most common orthodontic problems. In cases of class II malocclusion with mandibular deficiency, functional appliances often are used with the intent of stimulating mandibular growth. Bionator and twin block are two of the more popular functional appliances. The aim of this study was to compare the treatment outcomes of these two appliances using cephalometric radiographs. MATERIAL AND METHODS: Cephalometric radiographs of 33 patients who had class II division I malocclusion, before and after treatment were digitalized. The mean changes in twin block and bionator groups were compared using independent t test. RESULTS: Twin block and bionator showed no statistically significant differences in cephalometric parameters except for ANB, NA-Pog, Basal and Ar-Go-Me angles. CONCLUSIONS: There were no statistically significant differences in dentoalveolar and mandibular position between twin block and bionator (p>0.1). Twin block was more efficient in inhibition of forward movement of maxilla (p<0.1). Key words:Functional, Class II malocclusion, Cephalometrics, Twin block, Bionator, Treatment.

5.
Eye (Lond) ; 30(12): 1573-1578, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27540833

RESUMO

PurposeTo evaluate the effect of smoking on retrobulbar blood flow parameters by color Doppler imaging in patients with thyroid eye disease.Patients and methodsIn this observational case series, blood flow parameters in the ophthalmic artery, superior ophthalmic vein, central retinal artery, and vein were determined by color Doppler imaging in patients with thyroid eye disease. Patients were grouped as smokers and non-smokers. Never smokers and those who had stopped smoking for at least 1 year before onset of ophthalmopathy were considered as non-smokers. A thorough ophthalmic examination including Hertel exophthalmometry was performed. Orbital CT scan was also carried out in all patients.ResultsFifty-one orbits from 30 patients between 21 and 62 years old (mean±SD: 40.8±12.0) were enrolled in this study. Smokers had greater proptosis and more active and sever disease. (P<0.05) Muscle involvement based on CT scan did not vary in smokers and non-smokers. Maximum velocity (3.78±1.74 vs 5.27±2.14, P<0.001; t-test) and minimum velocity (1.74±0.78 vs 3.26±1.36, P =0.014; t-test) in superior ophthalmic vein were significantly lower in smokers than non-smokers. Even after adjusting for age, sex, and clinical activity score and severity, smokers had a lower minimum velocity in superior ophthalmic vein (P =0.01; ANCOVA analysis).ConclusionCigarette smoking may correlate with increase in orbital venous congestion in thyroid eye disease.


Assuntos
Oftalmopatia de Graves/fisiopatologia , Órbita/irrigação sanguínea , Fumar/efeitos adversos , Adulto , Análise de Variância , Velocidade do Fluxo Sanguíneo/fisiologia , Olho/irrigação sanguínea , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Oftálmica/fisiologia , Estudos Prospectivos , Fluxo Sanguíneo Regional/fisiologia , Artéria Retiniana/fisiologia , Veia Retiniana/fisiologia , Ultrassonografia Doppler em Cores , Adulto Jovem
6.
Bone Marrow Transplant ; 51(2): 219-26, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26595073

RESUMO

Reduced-intensity conditioning (RIC) has offered many primary immunodeficiency disorder (PID) patients who are ineligible for myeloablative regimens a chance of cure. However, the beneficial role of RIC was questioned following reports suggesting higher chance of rejection and lower symptom resolution rate in mixed chimerism settings. Forty-five children affected by PIDs with a median age of 21 months underwent allogeneic hematopoietic stem cell transplantation in our institute from 2007 to 2013. All patients received an identical RIC regimen. Forty-one patients had successful primary engraftment (91%). Of the successful engraftments, 80% (n=33) had stable full donor chimerism at last contact. Overall, eleven transplant-related mortalities were reported including five patients due to sepsis, three children due to grade IV acute GvHD, two due to chronic GvHD and one patient due to sepsis after primary graft failure. The median post-transplantation follow-up of deceased patients was 55 days. Five-year overall survival and disease-free survival was 75.6% and 68.89%, respectively. All surviving patients with successful engraftment became disease free, regardless of having full or mixed chimerism. Our study suggests that RIC regimen provides satisfactory rates of successful engraftment and full chimerism. Furthermore, patients with mixed chimerism were stable in long-term follow-up and this chimerism status offered the potential to resolve symptoms of immunodeficiency.


Assuntos
Soro Antilinfocitário/administração & dosagem , Transplante de Células-Tronco Hematopoéticas , Síndromes de Imunodeficiência , Melfalan/administração & dosagem , Condicionamento Pré-Transplante , Vidarabina/análogos & derivados , Adolescente , Adulto , Aloenxertos , Criança , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Síndromes de Imunodeficiência/mortalidade , Síndromes de Imunodeficiência/terapia , Masculino , Estudos Prospectivos , Taxa de Sobrevida , Fatores de Tempo , Vidarabina/administração & dosagem
7.
Diabetes Metab ; 42(1): 55-61, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26531321

RESUMO

AIM: Patients with diabetes are at greater risk of cardiovascular events. Insulin resistance (IR) and hyperinsulinaemia are both related to an increased cardiovascular risk, but whether IR predicts coronary heart disease (CHD) independently of other risk factors in patients with type 2 diabetes (T2D) is a topic of considerable controversy. The aim of the present study was to evaluate the prospective relationship of fasting insulin, HOMA-IR, fasting plasma glucose (FPG) and 2-h post-load glucose (2hPG) load with CHD incidence among such patients. METHODS: A total of 2607 patients with T2D were enrolled in a community-dwelling cohort and followed for an average of 7.2 years. Conventional CHD risk factors, FPG, 2hPG, fasting insulin levels and HOMA-IR index were measured at baseline. Cox regression hazard ratios (HRs) were used to assess CHD risk. RESULTS: A total of 299 'hard' CHD events were registered (in 114 women and 185 men). Increasing levels of fasting insulinaemia were positively associated with CHD incidence. This correlation persisted after controlling for gender, body mass index, blood pressure, lipid profile, medication use and HbA1c [HR for each increase in quartile (fully adjusted model): 1.18 (95% CI: 1.06-1.32); P<0.01]. 2hPG showed a non-linear association with incident CHD [HR of highest vs lowest quartile: 1.64 (95% CI: 1.03-2.61)]. Fasting glycaemia was not associated with CHD risk, whereas HOMA-IR had a direct and independent correlation with CHD risk [HR for each one-quartile increase: 1.19 (95% CI: 1.07-1.34); P<0.01]. CONCLUSION: Fasting insulin levels are positively associated with incidence of CHD in T2D. Furthermore, 2hPG appears to be a significant predictor of incident CHD independently of other risk factors, including HbA1c. These findings suggest that strategies targeting the reduction of insulinaemia and post-load glycaemia may be useful for preventing cardiovascular complications.


Assuntos
Glicemia/análise , Doença das Coronárias/sangue , Doença das Coronárias/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Hiperinsulinismo/sangue , Resistência à Insulina/fisiologia , Adulto , Idoso , Estudos de Coortes , Doença das Coronárias/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Jejum/sangue , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
8.
Clin Exp Obstet Gynecol ; 43(5): 713-717, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-30074324

RESUMO

BACKGROUND: Uterine leiomyomas could be considered as benign tumor of human uterus smooth muscle with unknown etiology and pathophysiology.Furthermore, they are the most common indication of hysterectomy. The tumor suppressor gene p53 has been involved in various malignancies. Mutation in its promoter site may play a role in tumorigenesis of many malignancies including leiomyompa. MATERIALS AND METHODS: For study of polymorphisms and allele frequency, 234 female patients with pathologically diagnosed uterine leiomyoma and 100 healthy blood donors as control group were assessed. DNAs were extracted from peripheral blood cells, amplified using polymerase chain reaction and restriction fragment length polymorphism (RFLP) technique was utilized for their analysis. RESULT: Proportions of A homozygote/heterozygote/G homozygote for SNP -250 A/G in leiomyoma group were 97.8%, 1.7%, and 0.4%, and in control group 97%, 3%, and 0%, respectively. In case of -216 T/C polymorphism, proportions of T homozygote/heterozygote/C homozygote in leiomyoma were 98%, 1.7%, and 0%, and in control samples 98%, 2%, and 0%, respectively. Genotype frequency of A homozygote/heterozygote/G homozygote for SNP-103 A/G was 97.9%, 1.7%, and 0.4% in leiomyoma group, and 98%, 2%, and 0% in control group, respectively. Proportions of A homozygote/heterozygote/G homozygote for SNP-33 A/G in leiomyoma group were 97.8%, 2.2%, and 0%, and 97%, 3%, and 0% in case samples, respectively. DISCUSSION: Based on the present results in an Iranian female population, surprisingly there was no significant differences between leiomyoma cases and control samples regarding allele frequencies of p53 promoter polymorphism.Therefore, The p53 promoter polymorphism is not associated with the susceptibility of uterine leiomyomas in Iranian women.


Assuntos
Predisposição Genética para Doença , Leiomioma/genética , Polimorfismo Genético , Regiões Promotoras Genéticas , Proteína Supressora de Tumor p53/genética , Neoplasias Uterinas/genética , Adulto , Feminino , Frequência do Gene , Genótipo , Humanos , Pessoa de Meia-Idade , Neoplasias Uterinas/etiologia
11.
Eye (Lond) ; 27(8): 899-905, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23703634

RESUMO

The carotenoids lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ) accumulate in the central retina, where they are collectively known as macular pigment (MP). Each of these three compounds exhibit a regional dominance, with MZ, Z, and L being the dominant carotenoids at the epicentre, mid-periphery, and periphery of the macula, respectively. There is a growing and evidence-based consensus that MP is important for optimal visual performance, because of its blue light-filtering properties and consequential attenuation of chromatic aberration, veiling luminance, and blue haze. It has also been hypothesised that MP may protect against age-related macular degeneration because of the same optical properties and also because of the antioxidant capacity of the three macular carotenoids. Challenges inherent in the separation and quantification of MZ have resulted in a paucity of data on the content of this carotenoid in foodstuffs, and have rendered the study of tissue concentrations of this compound problematic. As a consequence, the few studies that have investigated MZ have, perhaps, been disproportionately influential in the ongoing debate about the origins of this macular carotenoid. Certainly, the narrative that retinal MZ is derived wholly and solely from retinal L needs to be revisited.


Assuntos
Macula Lutea/química , Pigmentos da Retina/química , Xantofilas/metabolismo , Animais , Carotenoides/metabolismo , Suplementos Nutricionais , Humanos , Degeneração Macular/prevenção & controle , Ratos , Pigmentos da Retina/fisiologia , Xantofilas/química , Zeaxantinas
12.
J Med Eng Technol ; 36(1): 67-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22188577

RESUMO

PURPOSE: With the aim of facilitating core fistulectomy of high fistula-in-ano and reducing the risk of harmful injuries to sphincter muscles, we fabricated a novel fistulectomy set. METHODS: The set circumferentially separates approximately 2.5 mm thickness of the tract by moving a special tubular blade along it and removes the separated tissues by rotating a special cannulated screw which is housed in the blade. A straight rigid probe is used for identifying the tract path and guiding the device along it. RESULTS: We used this set for circumferential excision of fistula models created in cubic pieces of fresh cow muscle with excellent results. CONCLUSIONS: With regard to results of our tests, it is anticipated that the new set will provide significant advantages in treatment of high anal fistulas, namely noticeable reduction in the diameter of fistulectomy lumen, reducing the injuries to anal sphincters, minimizing the risk of faecal incontinence and shortening the convalescence period.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/instrumentação , Fístula Retal/cirurgia , Desenho de Equipamento , Humanos
13.
J Med Eng Technol ; 36(1): 8-16, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22074118

RESUMO

This paper presents a novel robotic sensory system 'Robo-Tac-BMI', which manipulates an indentation probe for the detection and three-dimensional localization of an abnormal mass embedded in the breast tissue. The Robo-Tac-BMI is designed based on artificial tactile sensing technology which is a new non-invasive method for mimicking the surgeon's palpation quantitatively. The intelligent processor of the device provides an overall stiffness map of the scanned areas. The extracted stiffness parameters provide a decisive factor for certifying the mass existence. Results are validated by 'gold standard' tests. Following the mass detection, its 3D localization is of essential importance in the treatment procedures. The planar 2D coordinate is readily available for all points on the tissue surface. Mass depth estimation is achieved by a comprehensive model utilizing the logistic regression algorithm and a Receiver Operating Characteristic (ROC) Curve for the highest accuracy. Statistical analysis is performed over 27 cases with 346 scanned areas.


Assuntos
Neoplasias da Mama/diagnóstico , Palpação/instrumentação , Robótica/instrumentação , Diagnóstico por Computador/métodos , Desenho de Equipamento , Feminino , Humanos , Imageamento Tridimensional , Palpação/métodos , Curva ROC , Robótica/métodos , Tato
14.
J Laryngol Otol ; 124(4): 456-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19941683

RESUMO

OBJECTIVE: We report a very rare case of a hydatid cyst in the infratemporal fossa, causing visual loss over a 10-day period, which disappeared with rapid surgical and medical treatment. CASE REPORT: A 14-year-old girl presented with right exophthalmos and visual loss. Over a 10-day period, her visual acuity had decreased to detection of hand motion only, due to pressure on the optic nerve caused by a parapharyngeal cyst pressing through a inferior orbital fissure on the right side. A craniotomy had previously been performed for a right frontoparietal hydatid cyst. The patient had been treated intermittently with albendazole. The patient was primarily diagnosed with hydatid cyst, on the basis of her previous medical history and radiological findings, and underwent surgery. Three cysts were carefully removed from the right maxillary sinus, via a standard Caldwell-Luc approach, and the surgical area was irrigated with hypertonic saline. CONCLUSION: Infratemporal hydatidosis is very rarely reported in the world literature, although hydatid cysts are endemic in many countries, including Iran. We discuss the common presenting features, investigation and treatment options for infratemporal hydatosis. Constant evaluation of adjacent organs is necessary, with treatment as required, due to the propensity of hydatidosis to recur in essential organs. Immediate surgery is recommended, both to prevent the development of disease and to improve the prognosis.


Assuntos
Cegueira/etiologia , Equinococose/diagnóstico , Adolescente , Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Equinococose/terapia , Feminino , Humanos , Seio Maxilar/parasitologia , Base do Crânio/parasitologia , Base do Crânio/cirurgia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Acuidade Visual
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