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101.

OBJECTIVE:

Strain and strain rate imaging is currently the most popular echocardiographic technique that reveals subclinical myocardial damage. There are currently no available data on this imaging method with regard to assessing right ventricular involvement in anterior myocardial infarction. Therefore, we aimed to evaluate right ventricular regional functions using a derived strain and strain rate imaging tissue Doppler method in patients who were successfully treated for their first anterior myocardial infarction.

METHODS:

The patient group was composed of 44 patients who had experienced their first anterior myocardial infarction and had undergone successful percutaneous coronary intervention. Twenty patients were selected for the control group. The right ventricular myocardial samplings were performed in three regions: the basal, mid, and apical segments of the lateral wall. The individual myocardial velocity, strain, and strain rate values of each basal, mid, and apical segment were obtained.

RESULTS:

The right ventricular myocardial velocities of the patient group were significantly decreased with respect to all three velocities in the control group. The strain and strain rate values of the right mid and apical ventricular segments in the patient group were significantly lower than those of the control group (excluding the right ventricular basal strain and strain rate). In addition, changes in the right ventricular mean strain and strain rate values were significant.

CONCLUSION:

Right ventricular involvement following anterior myocardial infarction can be assessed using tissue Doppler based strain and strain rate  相似文献   
102.
Abstract

Treatment of chronic skin wound such as diabetic ulcers, burns, pressure wounds are challenging problems in the medical area. The aim of this study was to design a bilayer skin equivalent mimicking the natural one to be used as a tissue engineered skin graft for use in the treatments of problematic wounds, and also as a model to be used in research related to skin, such as determination of the efficacy of transdermal bioactive agents on skin cells and treatment of acute skin damages that require immediate response. In this study, the top two layers of the skin were mimicked by producing a multilayer construct combining two different porous polymeric scaffolds: as the dermis layer a sodium carboxymethyl cellulose (NaCMC) hydrogel on which fibroblasts were added, and as the epidermis layer collagen (Coll) or chondroitin sulfate-incorporated collagen (CollCS) on which keratinocytes were added. The bilayer construct was designed to allow cross-talk between the two cell populations in the subsequent layers and achieves paracrine signalling. It had interconnected porosity, high water content, appropriate stability and elastic moduli. Expression of vascular endothelial growth factor (VEGF), basic-fibroblast growth factor (bFGF) and Interleukin 8 (IL-8), and the production of collagen I, collagen III, laminin and transglutaminase supported the attachment and proliferation of cells on both layers of the construct. Attachment and proliferation of fibroblasts on NaCMC were lower compared to performance of keratinocyte on collagen where keratinocytes created a dense and a stratified layer similar to epidermis. The resulting constructs succesfully mimicked in vitro the natural skin tissue. They are promising as grafts for use in the treatment of deep wounds and also as models for the study of the efficacy of bioactive agents on the skin.  相似文献   
103.

Purpose

Primary immunodeficiency diseases (PIDs) are inherited disorders of the immune system resulting in increased susceptibility to unusual infections and predisposition to autoimmunity and malignancies. The European Society for Immunodeficiencies (ESID) has developed an internet-based database for clinical and research data on patients with PID. This study aimed to provide a minimum estimate of the prevalence of each disorder and to determine the clinical characteristics and outcomes of patients with PID in Turkey.

Methods

Clinical features of 1435 patients with primary immunodeficiency disorders are registered in ESID Online Patient Registry by the Pediatric Immunology Departments of the Medical Faculties of Uludag University and Ege University Between 2004 and 2010. These two centers are the major contributors reporting PID patients to ESID database from Turkey.

Results

Predominantly antibody immunodeficiency (73.5 %) was the most common category followed by autoinflammatory disorders (13.3 %), other well defined immunodeficiencies (5.5 %), congenital defects of phagocyte number, function or both 3.5 %), combined T and B cell immunodeficiencies (2 %), defects in innate immunity (1 %), and diseases of immune dysregulation (0.7 %). Patients between 0 and 18 years of age constitued 94 % of total and the mean age was 9.2?±?6 years. The consanguinity rate within the registered patients was 14.3 % (188 of 1130 patients). The prevalance of all PID cases ascertained from the registry was 30.5/100.000. The major cause of the mortality was severe infection which was seen in forty-two of seventy five deceased patients. The highest mortality was observed in patients with severe combined immunodeficiencies and ataxia-telangiectasia.

Conclusion

Promoting the awareness of PID among the medical professionals and the general public is required if premature death and serious morbidity occurs due to late diagnosis of the wider spectrum of PID are to be avoided.  相似文献   
104.
Current evidence strongly suggests that aberrant activation of the nuclear factor kappa B (NF-kB) signaling cascade is connected to carcinogenesis. The matrix metalloproteinases (MMP) which are also the key agents for tumor metastasis may be potent candidates for tumor diagnosis in clinics. In this in vitro study, we hypothesized that metformin with an effective dose can inhibit tumor cell proliferation and metastasis by modulating the expressions of MMP-2 and -9 and interfering with NF-kB signaling in primary breast cancer cells (PBCCs). 300 000 cells per ml were obtained from biopsies of breast tumors from five human donors. The cell viability and proliferation were tested. Immunocytochemistry was performed for MMP-2, MMP-9, and NF-kB, and enzyme-linked immunosorbent assay for NF-kB activity, quantitative real-time PCR for RELA/p65, IkBα, MMP-2, and MMP-9. Three different doses of metformin (5, 10, and 25 mM) (Met) reduced the viability and proliferation of PBCCs in a dose-dependent manner, maximum inhibition was observed at 25 mM Met. The expression of RELA/p65 was not affected by 25 mM Met. Nuclear immunoreactivity and activity of NF-kB reduced while cytoplasmic NF-kB (p65) elevated by 25 mM Met compared to non-treatment (P < 0.05). The expression and immunoreactivity of MMP-9 but not MMP-2 were decreased by 25 mM Met treatment, compared with the non-treatment (P < 0.05). Metformin may have an essential antitumor role in the invasion and metastasis pathways of PBCCs by downregulating the MMP-9 expression blocking both the activity and nuclear translocation of NF-kB.  相似文献   
105.
BACKGROUND: Division of the sternum is primarily a blind procedure in reoperation and carries an increased risk of injury for major cardiac structures in the presence of adhesions between the posterior table and the heart. METHODS: Two hundred patients were randomly divided into two groups. Cardiopulmonary bypass was established through the femoral artery and vein in group 1 (n = 100) patients before sternal reentry. Carpentier dual-stage femoral venous return cannula was used in all group 1 patients. Cardiopulmonary bypass was performed after sternal reentry in group 2 (n = 100) patients. RESULTS: Six severe cardiac injuries developed in group 2. Cardiopulmonary bypass time was 93 +/- 9 minutes in group 1 and 71 +/- 11 minutes in group 2 (p = 0.011), and the operation time was 155 +/- 23 minutes in group 1 and 185 +/- 32 minutes in group 2 (p = 0.024). Inotropic therapy was required in 52 patients in group 1 and 76 patients in group 2 (p = 0.032). Average chest drainage was 450 +/- 135 mL in group 1 and 850 +/- 250 mL in group 2 (p < 0.001). Average fresh whole blood transfusion was 3.3 +/- 1.2 U in group 1 and 5.8 +/- 0.9 U in group 2 (p = 0.033). Average intensive care unit stay was 2.2 +/- 1.3 days in group 1 and 4.5 +/- 2.3 days in group 2 (p = 0.025). Average hospital stay was 7.3 +/- 2.4 days in group 1 and 9.1 +/- 3.1 days for group 2 (p = 0.011). CONCLUSIONS: Cardiopulmonary bypass by bicaval Carpentier femoral venous cannula before resternotomy not only allows adequate cardiopulmonary bypass flow but also significantly reduces the risk of cardiac injury and catastrophic hemorrhage and allows safe reopening. Although this procedure increases cardiopulmonary bypass time, the operation time, bleeding, and blood transfusion requirement are significantly reduced.  相似文献   
106.
107.
Within the spectrum of acute aortic syndromes, intramural hematoma (IMH) is a distinct lesion that is characterized by crescentic or circumferential thickening of the aortic wall in the absence of an intimal defect. The reported incidence of IMH among all type A acute aortic syndromes ranges from 3.5% to 28.3%. As compared with acute aortic dissection, IMH is a disease of the elderly, and it tends to have reduced rates of malperfusion syndromes, aortic insufficiency, and root dilation, yet also tends to have increased rates of pericardial effusion, cardiac tamponade, and periaortic hematoma. With respect to natural history, IMH may progress to classic dissection, frank rupture, or aneurysmal dilation; yet, IMH may also regress and be completely resorbed. However, studies disagree over the rates of progression or regression; as such, few studies agree on the short-term and long-term prognosis associated with IMH. American and European guidelines advocate emergent surgery for all acutely presenting type A IMH. At a minimum, supracoronary replacement of the aorta with hemiarch reconstruction is the preferred extent of operative repair to reduce rates of long-term reintervention for disease progression. However, valve and/or root procedures may be necessary proximally, while total arch reconstruction or hybrid procedures for the descending aorta may be necessary distally. Much remains unknown for IMH, including the ideal extent of aortic repair, risk-stratification for elderly patients, and the optimal treatment paradigm for stable, uncomplicated IMH. As such, IMH remains a diagnostic and therapeutic challenge for the cardiovascular surgeon.  相似文献   
108.
IntroductionThe aim of this in vitro study was to assess and compare the effect of photoactivated disinfection (PAD) on the bond strength of root canal sealers to human root canal dentin using the push-out test.MethodsFifteen extracted human mandibular premolar teeth with single and straight roots were used. After the clinical crowns were removed from the cementoenamel junction, root canals were prepared with the ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) rotary system to the size of the F3 file. The smear layer of the roots was removed using 17% EDTA followed by 5.25% sodium hypochlorite (NaOCl) and distillate water. The roots were then randomly divided into 3 groups (n = 5) according to the final irrigation regimen. In group 1, PAD (FotoSan; CMS Dental, Copenhagen, Denmark) was applied to the root canals and light cured for 20 seconds. Group 2 was finally irrigated with a 2% solution of chlorhexidine gluconate, and group 3 served as the control group (NaOCl + EDTA). All the canals were then obturated with the lateral condensation technique using gutta-percha and AH Plus sealer (Dentsply Maillefer) sealer. One-millimeter-thick horizontal sections from the coronal and midthirds of each root (n: 5 × 4 = 20) were sliced for the push-out bond strength measurement. The data were converted to megapascals and statistically analyzed using 1-way analysis of variance and the post hoc Tukey test.ResultsThere was no significant difference among the bond strength of PAD, chlorhexidine gluconate, and NaOCl (P > .05).ConclusionsWe conclude that PAD does not adversely affect the bond strength of the AH Plus sealer to root canal dentin and that it can be used for the final disinfection of root canals.  相似文献   
109.
Recent evidence exists that enoxaparin can reduce brain injury because of its anticoagulant activity. To investigate the potential therapeutic effect of enoxaparin on cold-induced traumatic brain injury, at 20 minutes after modeling, male BALB/c mouse models of cold-induced traumatic brain injury were intra-peritoneally administered 3 and 10 mg/kg enoxaparin or isotonic saline solution. Twenty-four hours later, enoxaparin at 10 mg/kg greatly reduced infarct volume, decreased cell apoptosis in the cortex and obviously increased serum level of total antioxidant status. By contrast, administration of enoxaparin at 3 mg/kg did not lead to these changes.These findings suggest that enoxaparin exhibits neuroprotective effect on cold-in-duced traumatic brain injury in a dose-dependent manner.  相似文献   
110.
Aim/Background: Restless legs syndrome (RLS) is a frequent neurological and sleep disorder. Metabolic disorders are known to be related to sleep disorders. We prospectively evaluated whether obesity and its possible cofactors were related to the presence of RLS.

Materials and Methods: The study included 143 obese and 94 non-obese individuals. Obese patients had a BMI of 30 and over, while non-obese patients had a BMI lower than 30. Patients with arthritis and pregnancy were excluded but not those with diabetes mellitus. Participants who met diagnostic criteria recommended by the International RLS Study Group were diagnosed as having RLS. Depression, anxiety, daytime sleepiness, insomnia and sleep quality were evaluated in detail.

Results: The mean age of obese patients was 40.52 years and that of non-obese patients was 39.76 years. The mean body mass index was 36.77 in the obese group and 25.71 in the non-obese group. The occurrence of depression, anxiety, sleep quality, and insomnia scores were significantly higher in obese individuals. The evaluations of daytime sleepiness, sleep efficiency and sleep latency were not significantly different between the groups.

Discussion: Although the presence of RLS was correlated with obesity and vascular risk factors at a significant level, it was also shown that depression, anxiety and insomnia were significantly frequent in obese patients (although not daytime sleepiness). Further studies are needed.  相似文献   

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