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41.
Neshat Eghbali Homam Naffakh-Moosavy Sanam Sadeghi Mohammadi Hossein Naderi-Manesh 《Dental materials》2021,37(3):547-558
ObjectiveMicro-nano scale surface modification of Ti-6Al-4V was investigated through the fascinated modern fiber engraving laser method. The process was performed at a high laser speed of 2000 mm/s, under different laser frequencies (20–160 kHz) and groove distances (0.5–50 μm).MethodsTopographic evaluations such as Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscopy (FE-SEM) were used to identify the quality and regularity of patterns. The proliferation of human osteoblast-like osteosarcoma cells (MG63) was analyzed by MTT assay for up to 72 h. Also, the plate counting method was used to quantify the viability potential of the modified surface against Escherichia coli bacteria.ResultsThe cellular viability of the sample modified at the laser frequency of 20 kHz and grooving distance of 50 μm increased up to 35 and 10% compared to the non-treated and control samples, respectively. In the case of the surface modification at lower grooving distances range between 0.5–50 μm, the maximum laser frequency (160 kHz) applied leads to lower pulse’s energies and less bacterial adhesion. Otherwise, at groove distances more than 50 μm, the minimum laser frequency (20 kHz) applied reduces the laser pulse overlaps, increases the cell adhesion and antibacterial properties.SignificanceSurface modification by the fiber engraving laser process significantly enhances the cell adhesion on the surface. As a result of such roughness and cell adhesion enhancement, the surface toxicity feature diminished, and its antibacterial properties improved. 相似文献
42.
Lupus mastitis (LM) is a rare benign inflammatory condition characterized by inflammation of the deep subcutaneous adipose tissues of the breast. It can be seen in patients with a known history of systemic lupus erythematous or discoid lupus or rarely can be the initial presentation of these diseases. Histologically, the most common findings are the presence of a dense lymphoplasmacytic infiltration of lobules and hyaline fat necrosis. Radiologic characteristics of LM can mimic a malignant lesion. However, because histologic features of this lesion have been well defined, correlation with clinical history is important to arrive at an accurate diagnosis and, therefore, deliver appropriate patient management. Herein, we present a review of LM with emphasis on clinicopathologic findings and differential diagnosis. 相似文献
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Alfredo Nunes Ferreira-Neto Tania Rodriguez-Gabella Leonardo Guimaraes Afonso Freitas-Ferraz Mathieu Bernier Camila Figueiredo Guimaraes Sergio Pasian Jean-Michel Paradis Robert Delarochellière Eric Dumont Siamak Mohammadi Dimitri Kalavrouziotis Mélanie Côté Philippe Pibarot Josep Rodés-Cabau 《Revista espa?ola de cardiología》2021,74(3):247-256
Introduction and objectivesWe assessed the long-term hemodynamic performance of transcatheter heart valve (THV) by paired transthoracic echocardiography (TTE), and the incidence, characteristics and factors associated with THV structural valve degeneration (SVD).MethodsA total of 212 patients who underwent transcatheter aortic valve replacement and had a potential follow-up > 5 years with at least 1 TTE ≥ 1-year postprocedure were included. All patients had a TTE at 1 to 5 years and 36 had another one at 6 to 10 years. SVD was defined as subclinical (increase > 10 mmHg in mean transvalvular gradient + decrease > 0.3 cm2 in valve area and/or new-onset mild or moderate aortic regurgitation) and clinically relevant (increase > 20 mmHg in mean transvalvular gradient + decrease > 0.6 cm2 in valve area and/or new-onset moderate-to-severe aortic regurgitation). Fifteen patients had a transesophageal echocardiography at the time of SVD diagnosis, and 85 an opportunistic computed tomography examination at 1 (0.5-2) years.ResultsTransvalvular mean gradient increased and valve area decreased over time (P < .01). At 8 years of follow-up, SVD occurred in 30.2% of patients (clinically relevant: 9.3%). Transesophageal echocardiography revealed thickened and reduced-mobility leaflets in 80% and 73% of SVD cases, respectively. No baseline or procedural factors were associated with SVD. THV underexpansion (3.5%) or eccentricity (8.2%) had no impact on valve hemodynamics/SVD at follow-up.ConclusionsA gradual THV hemodynamic deterioration occurred throughout a 10-year period, leading to SVD in ~30% of patients (clinically relevant in < 10%). Leaflet morphology/mobility were frequently impaired in SVD cases, but THV geometry did not influence valve hemodynamics or SVD. 相似文献
45.
Sima Rostami Shams Shariat Torbaghan Shahriar Dabiri Zahra Babaei Mohammad Ali Mohammadi Mitra Sharbatkhori Majid Fasihi Harandi 《The American journal of tropical medicine and hygiene》2015,92(3):588-594
Cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, presents an important medical and veterinary problem globally, including that in Iran. Different genotypes of E. granulosus have been reported from human isolates worldwide. This study identifies the genotype of the parasite responsible for human hydatidosis in three provinces of Iran using formalin-fixed paraffin-embedded tissue samples. In this study, 200 formalin-fixed paraffin-embedded tissue samples from human CE cases were collected from Alborz, Tehran, and Kerman provinces. Polymerase chain reaction amplification and sequencing of the partial mitochondrial cytochrome c oxidase subunit 1 gene were performed for genetic characterization of the samples. Phylogenetic analysis of the isolates from this study and reference sequences of different genotypes was done using a maximum likelihood method. In total, 54.4%, 0.8%, 1%, and 40.8% of the samples were identified as the G1, G2, G3, and G6 genotypes, respectively. The findings of the current study confirm the G1 genotype (sheep strain) to be the most prevalent genotype involved in human CE cases in Iran and indicates the high prevalence of the G6 genotype with a high infectivity for humans. Furthermore, this study illustrates the first documented human CE case in Iran infected with the G2 genotype. 相似文献
46.
Esa Jämsen 《Acta orthopaedica》2015,86(2):175-182
Background and purpose — Perioperative hyperglycemia has been associated with adverse outcomes in several fields of surgery. In this observational study, we identified factors associated with an increased risk of hyperglycemia following hip and knee replacement.Patients and methods — We prospectively monitored changes in glucose following primary hip and knee replacements in 191 patients with osteoarthritis. Possible associations of patient characteristics and operation-related factors with hyperglycemia (defined as glucose > 7.8 mmol/L in 2 consecutive measurements) and severe hyperglycemia (glucose > 10 mmol/L) were analyzed using binary logistic regression with adjustment for age, sex, operated joint, and anesthesiological risk score.Results — 76 patients (40%) developed hyperglycemia, and 48 of them (25% of the whole cohort) had severe hyperglycemia. Glycemic responses were similar following hip replacement and knee replacement. Previously diagnosed diabetes was associated with an increased risk of hyperglycemia and severe hyperglycemia, compared to patients with normal glucose metabolism, whereas newly diagnosed diabetes and milder glucose metabolism disorders had no effect. In patients without previously diagnosed diabetes, increased values of preoperative glycosylated hemoglobin (HbA1c) and fasting glucose on the day of operation were associated with hyperglycemia. Higher anesthesiological risk score—but none of the operation-related factors analyzed—was associated with an increased risk of hyperglycemia.Interpretation — Perioperative hyperglycemia is common in primary hip and knee replacements. Previously diagnosed diabetes is the strongest risk factor for hyperglycemia. In patients with no history of diabetes, preoperative HbA1c and fasting glucose on the day of operation can be used to stratify the risk of hyperglycemia. 相似文献
47.
Sarraf-Zadegan N Sadri G Malek Afzali H Baghaei M Mohammadi Fard N Shahrokhi S Tolooie H Poormoghaddas M Sadeghi M Tavassoli A Rafiei M Kelishadi R Rabiei K Bashardoost N Boshtam M Asgary S Naderi G Changiz T Yousefie A 《Acta cardiologica》2003,58(4):309-320
The Isfahan Healthy Heart Programme (IHHP) is a five to six year comprehensive integrated community-based programme for cardiovascular diseases (CVD) prevention and control via reducing CVD risk factors and improvement of cardiovascular healthy behaviour in a target population. IHHP started late in 1999 and will be finished in 2005-2006. A primary survey was done to collect baseline data from interventional (Isfahan and Najaf-Abad) and reference (Arak) communities. In a two-stage sampling method, we randomly selected 5 to 10 percent of households from randomly selected clusters. Then individuals aged > or = 19 years were selected for the survey. This way, data from 12,600 individuals (6300 in interventional counties and 6300 in the reference county) was collected and stratified according to living area (urban vs. rural) and different age and sex groups. The samples underwent a 30-minute interview to complete validated questionnaires containing questions on demography, socioeconomic status, smoking behaviour, physical activity, nutritional habits and other behaviour regarding CVD. Blood pressure and body mass index (BMI) measurements were done and fasting blood samples were taken for two hours post load plasma glucose (2 hpp), serum (total, HDL and LDL) cholesterol and triglyceride levels. A twelve-lead electrocardiogram was recorded in all persons above 35 years of age. Community-wide surveillance of deaths, hospital discharges, myocardial infarction and stroke registry was carried out in the intervention and control areas. Four to five years of interventions based on different categories such as mass media, community partnerships, health system involvement and policy and legislation have started in the intervention area while Arak will be followed without intervention. Considering the results of the baseline surveys, (assessments needed, the objectives, existing resources and the possibility of national implementation) the interventions were planned. They were set based on specific target groups like school children, women, work-site, health personnel, high-risk persons, and community leaders were actively engaged as decision makers. A series of teams was arranged for planning and implementation of the intervention strategies. Monitoring will be done on small samples to assess the effect of different interventions in the intervention area. While four periodic surveys will be conducted on independent samples to assess health behaviours related to CVD risk factors in the intervention and reference areas, the original pre-intervention subjects aged more than 35 years will be followed in both areas to assess the individual effect of interventions and outcomes like sudden death, fatal and nonfatal MI and stroke. The whole baseline survey will be repeated on the original and an independent sample in both communities at the end of the study. 相似文献
48.
Durga Praveen Meka Anne Kathrin Müller-Rischart Prakash Nidadavolu Behnam Mohammadi Elisa Motori Srinivas Kumar Ponna Helia Aboutalebi Mahmoud Bassal Anil Annamneedi Barbara Finckh Margit Miesbauer Natalie Rotermund Christian Lohr J?rg Tatzelt Konstanze F. Winklhofer Edgar R. Kramer 《The Journal of clinical investigation》2015,125(5):1873-1885
Parkin and the glial cell line–derived neurotrophic factor (GDNF) receptor RET have both been independently linked to the dopaminergic neuron degeneration that underlies Parkinson’s disease (PD). In the present study, we demonstrate that there is genetic crosstalk between parkin and the receptor tyrosine kinase RET in two different mouse models of PD. Mice lacking both parkin and RET exhibited accelerated dopaminergic cell and axonal loss compared with parkin-deficient animals, which showed none, and RET-deficient mice, in which we found moderate degeneration. Transgenic expression of parkin protected the dopaminergic systems of aged RET-deficient mice. Downregulation of either parkin or RET in neuronal cells impaired mitochondrial function and morphology. Parkin expression restored mitochondrial function in GDNF/RET-deficient cells, while GDNF stimulation rescued mitochondrial defects in parkin-deficient cells. In both cases, improved mitochondrial function was the result of activation of the prosurvival NF-κB pathway, which was mediated by RET through the phosphoinositide-3-kinase (PI3K) pathway. Taken together, these observations indicate that parkin and the RET signaling cascade converge to control mitochondrial integrity and thereby properly maintain substantia nigra pars compacta dopaminergic neurons and their innervation in the striatum. The demonstration of crosstalk between parkin and RET highlights the interplay in the protein network that is altered in PD and suggests potential therapeutic targets and strategies to treat PD. 相似文献
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