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61.
The feasibility of using modified Allen tests to evaluate arterial circulation in the forearm for possible radial artery grafting, and the correlation of these tests with Doppler ultrasonography, were examined. The hand circulation of 50 patients scheduled for coronary artery bypass grafting was assessed by plethysmography, pulse oximetry, and pencil Doppler, as well as Doppler ultrasonography. Flow, velocity, and diameter of the radial, ulnar, and snuffbox arteries were recorded, and radiological screening indices were evaluated to establish a standard set of criteria. The results of modified Allen tests by plethysmography and pulse oximetry demonstrated the dominance of the ulnar artery. The indices of flow x diameter and velocity x diameter, obtained from Doppler ultrasound measurements, confirmed the dominance of the ulnar artery. When compression was applied to the arteries sequentially, significant alterations were found. The arterial circulation in the forearm can be safely evaluated by the modified Allen tests with plethysmography, pulse oximetry, and pencil Doppler, as these results correlated with Doppler ultrasound.  相似文献   
62.
Subvalvular apparatus preservation is an important concept in mitral valve replacement (MVR) surgery that is performed to remedy mitral regurgitation. In this study, we sought to determine the effects of papillary muscle repositioning (PMR) on clinical outcomes and echocardiographic left ventricular function in rheumatic mitral stenosis patients who had normal left ventricular systolic function.We prospectively assigned 115 patients who were scheduled for MVR surgery with mechanical prosthesis to either PMR or MVR-only groups. Functional class and echocardiographic variables were evaluated at baseline and at early and late postoperative follow-up examinations. All values were compared between the 2 groups.The PMR group consisted of 48 patients and the MVR-only group of 67 patients. The 2 groups’ baseline characteristics and surgery-related factors (including perioperative mortality) were similar. During the 18-month follow-up, all echocardiographic variables showed a consistent improvement in the PMR group; the mean left ventricular ejection fraction deteriorated significantly in the MVR-only group. Comparison during follow-up of the magnitude of longitudinal changes revealed that decreases in left ventricular end-diastolic and end-systolic diameters and in left ventricular sphericity indices, and increases in left ventricular ejection fractions, were significantly higher in the PMR group than in the MVR-only group.This study suggests that, in patients with rheumatic mitral stenosis and preserved left ventricular systolic function, the addition of papillary muscle repositioning to valve replacement with a mechanical prosthesis improves left ventricular dimensions, ejection fraction, and sphericity index at the 18-month follow-up with no substantial undesirable effect on the surgery-related factors.Key words: Cardiac output, chordae tendineae/surgery, left ventricular function, mitral valve replacement, mitral valve stenosis/surgery, papillary muscles/surgery, subvalvular apparatus, tissue preservation/methods, ventricular function, leftMitral valve replacement (MVR) with a mechanical or a bioprosthetic valve is one of the most performed cardiac surgical procedures. Although in recent years valve repair has usually been preferred to replacement, MVR is inevitable when repair is not feasible. After MVR, low cardiac output syndrome develops in some patients, because the subvalvular apparatus has not been spared.1 Because the subvalvular apparatus provides continuity between the mitral annulus and the left ventricular (LV) wall through the leaflets, chordae tendineae, and papillary muscles, it plays an important role in LV function.2 Several studies33 have shown that protection of the subvalvular apparatus during MVR can decrease the risk of low cardiac output syndrome, reduce the operative mortality rate, and improve postoperative LV systolic function. Various approaches to subvalvular apparatus preservation have been developed.69Papillary muscle repositioning (PMR) is a subvalvular apparatus-sparing method that can be applied to both the anterior and posterior mitral annulus. In patients with LV dysfunction and mitral regurgitation, several studies10,11 have shown favorable effects of papillary muscle repositioning on LV remodeling; however, the effect of subvalvular-apparatus-sparing surgery (including PMR) on LV mechanics has not yet been fully elucidated in patients who have isolated mitral stenosis and preserved LV function.12,13In this study, we examined the effectiveness of PMR on LV function and clinical outcome in patients with isolated mitral stenosis and preserved LV systolic function who undergo MVR.  相似文献   
63.
Hemodialysis patients are at increased risk of latent tuberculosis infection (LTBI) compared with the general population. QuantiFERON-TB Gold (QFT-G) for LTBI detection is more promising than tuberculin skin test (TST) in hemodialysis patients. The aim of this study is to determine whether the QFT-G is more sensitive than the TST in hemodialysis patients in LTBI. Eighty nine hemodialysis patients were evaluated for latent tuberculosis infection with the TST and QFT-G. Blood was obtained for QFT-G, and then TST was administered to all patients. Demographic information, laboratory tests, chest radiography results and BCG vaccination status were collected on standardized patient medical files. Forty patients had positive QFT-G results. 56 patients had TST induration above 5 mm, 28 patients above 10 mm. 61 patients had BCG vaccination scar. Statistically significant correlation was detected between TST and QFT-G (p< 0.05). In the BCG non-vaccinated subgroup, TST was positive in 8 (29%) patients and the QFT-G was positive in 11 (39%). Among the 21 non vaccinated patients with results for both tests, the concordance between the TST and QFT-G was 82%, k= 0.61, p= 0.001. We found good agreement between the TST and QFT-G test for LTBI in non vaccinated hemodialysis patients, whereas we found poor agreement in vaccinated patients. Because BCG vaccination is widely used in our country, the QFT-G test might be more useful for the diagnosis of LTBI than TST in hemodialysis patients who are suspected to have LTBI.  相似文献   
64.
Large deletions in the first intron of the With No lysine (K) 1 (WNK1) gene are responsible for Familial Hyperkalemic Hypertension (FHHt), a rare form of human hypertension associated with hyperkalemia and hyperchloremic metabolic acidosis. We generated a mouse model of WNK1-associated FHHt to explore the consequences of this intronic deletion. WNK1+/FHHt mice display all clinical and biological signs of FHHt. This phenotype results from increased expression of long WNK1 (L-WNK1), the ubiquitous kinase isoform of WNK1, in the distal convoluted tubule, which in turn, stimulates the activity of the Na–Cl cotransporter. We also show that the activity of the epithelial sodium channel is not altered in FHHt mice, suggesting that other mechanisms are responsible for the hyperkalemia and acidosis in this model. Finally, we observe a decreased expression of the renal outer medullary potassium channel in the late distal convoluted tubule of WNK1+/FHHt mice, which could contribute to the hyperkalemia. In summary, our study provides insights into the in vivo mechanisms underlying the pathogenesis of WNK1-mediated FHHt and further corroborates the importance of WNK1 in ion homeostasis and blood pressure.Familial Hyperkalemic Hypertension (FHHt) is a rare disorder featuring hypertension, hyperkalemia, and hyperchloremic metabolic acidosis (Online Mendelian Inheritance in Man, OMIM, 145260) (1, 2). Twelve years ago, mutations in the With No lysine (K) 1 (WNK1) and WNK4 genes were shown to cause FHHt (3), initiating a field of extensive research on the regulation of blood pressure and ion homeostasis by these two serine-threonine kinases of the WNK family (review in ref. 4). Many questions, however, regarding their physiological roles and the mechanisms of WNK1-related FHHt still remain.The human mutations identified at the WNK1 locus do not modify the coding sequence but are large deletions in the 60-kb-long first intron, which result in an overexpression of WNK1 in the leukocytes of patients (3). The WNK1 gene generates two isoforms through alternative promoters. The long isoform, long WNK1 (L-WNK1), is expressed ubiquitously, whereas the shorter isoform, kidney-specific WNK1 (KS-WNK1), which lacks a functional kinase domain, is expressed specifically in the kidney (5). In the kidney, L-WNK1 is expressed at a low level in all nephron segments, whereas KS-WNK1 is expressed only in the distal nephron (6). We previously generated a transgenic mouse model that exhibited an ectopic expression of KS-WNK1 and an increased expression of L-WNK1 in the distal nephron on deletion of the first intron (7). This model, however, did not allow the study of the functional consequences of the deletion of WNK1 first intron, because a reporter gene was inserted under the control of each WNK1 promoter within the transgene.Several in vitro experiments suggest that an increase in L-WNK1 expression in the distal nephron could trigger the development of FHHt. The kinase can, indeed, stimulate the activity of the Na+–Cl cotransporter (NCC), which has been established as an essential component of the FHHt phenotype, through its interaction with either WNK4 and/or Ste20-related proline-alanine rich kinase (SPAK) (review in ref. 4). WNK4 inhibits NCC, and L-WNK1 relieves the cotransporter from this inhibition. L-WNK1 phosphorylates and thus, activates SPAK, which in turn, stimulates NCC membrane expression by phosphorylation. However, the characterization of L-WNK1 function in the distal nephron has been hampered by the absence of a valid mouse model, because L-WNK1 inactivation results in embryonic death caused by cardiovascular defects (8, 9).To understand how the intronic deletion leads to FHHt, we generated a mouse model harboring a heterozygous deletion in the endogenous first intron of WNK1 to reproduce the human genetic situation. These mice exhibit hyperkalemia, hypertension, and metabolic acidosis, which seem to result from NCC activation. This phenotype results from a twofold increase in L-WNK1 expression in the distal convoluted tubule (DCT) and a slightly increased expression of L-WNK1 in the connecting tubule (CNT), with no modification of KS-WNK1 expression. We also show that the activity of epithelial sodium (Na) channel (ENaC) is not altered in WNK1+/FHHt mice, whereas the expression of renal outer medullary potassium (K) channel (ROMK) is decreased in the late DCT and CNT; this finding suggests that the hyperkalemia observed in WNK1+/FHHt is not caused by decreased ENaC activity but, at least in part, by a decreased K+ excretion caused by the inhibition of ROMK by L-WNK1.  相似文献   
65.
Bone continuity defects in the mandible are caused by tumor surgery, trauma, infection, or osteoradionecrosis. Today, reconstruction of long-span mandibular defects with a free fibular flap is a routine procedure. However the bone height of the mandible after reconstruction is about half that of the dentulous mandible. Therefore, the deficiency in bone height makes implant placement impractical. In our case, because it was necessary to restore the mandibular height, a vertical distraction osteogenesis was performed on the grafted mandible of the patient who was referred to our clinic with a reconstructed mandible owing to a gunshot injury. As a result, the vertical discrepancy between the fibula and the native hemimandible of the patient was corrected. And the placement of dental implants was performed without any complications. In conclusion, we believe that the vertical distraction osteogenesis of free vascularized fibula flaps is a reliable technique that optimizes implant positioning for ideal prosthetic rehabilitation.  相似文献   
66.
AIM: To investigate diabetic retinopathy (DR) literature using the Institute for Scientific Information (ISI) Web of Science (WoS) database and to analyse the correlation results between socio-economic development datas and number of DR publications. METHODS: The statistical analysis of the documents published during 1980-2014 was analysed. The data of this study were based on the database of WoS. “Diabetic retinopathy” was used as the keywords to search the WoS database. RESULTS: The United States ranked first in the DR research with 1840 publications and 24.38% of the world production followed by England and Japan. Besides, the most productive country was Iceland. A high correlation was found between number of publications and 2014 gross domestic product (GDP) values of 81 countries (r=0.800, P<0.001). We found a significant correlation between number of publications and Human Development Index (HDI) (r=0.645, P=0.001). There is a moderate correlation between people with diabetes and number of DR publications for 81 countries (r=0.514, P<0.01). It could be analysed that estimated publication number with DR title will be 445 according to the regression curve constituted with cubic model in 2015 (R2=1.000). CONCLUSION: More DR studies have been published in developed countries, DR and other complications of diabetes have gradually increased in developing countries over recent decades. It can be expected that the number of DR studies will gradually increase in developing countries.  相似文献   
67.
Subclinical hypothyroidism and subclinical hyperthyroidism are two frequently occurring conditions for which exact therapeutic approaches have not yet been established. The aim of this study was to compare the endothelial function and carotid artery intimae-media thickness (IMT) of these two groups of patients to euthyroid subjects and to assess the effects of these conditions on endothelial function. Study groups comprised of 25 subclinical hypothyroid patients (mean age, 32.28 +/- 9.67 years), 13 subclinical hyperthyroid patients (mean age, 35.69 +/- 9.67 years), and 23 euthyroid subjects (mean age, 35.87 +/- 7.93 years). They were evaluated for flow-mediated dilatation (FMD), and carotid artery IMT. The groups were matched strictly for atherosclerotic risk factors. The subclinical hypothyroid group was found to have significantly lower FMD values. No significant differences were observed between the groups with respect to other vascular parameters. The only discriminative factor between the groups was the state of their thyroid function. Therefore, subclinical hypothyroidism may have adverse effects on endothelial function independent from other well-known atherosclerotic risk factors.  相似文献   
68.
Abstract Coronary‐coronary bypass grafting refers to making anastomoses between two segments of the same coronary artery or between different coronary arteries, and provides less “touch” to the aorta, which is important for the patients with severely atherosclerotic ascending aorta. In this report we represent a case of a patient with extensive atherosclerotic aorta, in whom a saphenous vein graft was placed between the acute marginal and the posterior‐descending branches of the right coronary artery during an off‐pump coronary artery bypass grafting surgery. (J Card Surg 2010;25:167‐169)  相似文献   
69.

Background  

The matrix metalloproteinase-1 enzyme (MMP-1, also called collagenase 1) plays a key role in turnover of collagen fibers in the intercellular matrix. Insertion of a guanine residue was found within the promoter region of the MMP-1 gene. We found that MMP-1 levels increased approximately twofold over normal when this insertion was present, enabling MMP-1 to facilitate tumor invasion and metastasis. MMP-1 is also believed to play a role in tumor development. The aim of our study is to investigate the effect of polymorphisms in the promoter region of the MMP-1 gene on the development of benign and invasive hypophyseal adenomas.  相似文献   
70.
A possible cause for dental implant failure is the periapical implant lesion (PIL). In this case report we describe an apical periodontitis on a tooth adjacent to a dental implant that may have communicated with the apical region of the dental implant, and causing retrograde peri-implantitis. To our knowledge this is the first report demonstrating the concomitant successful treatment of the periapical implant pathology and the adjacent natural tooth without the removal of the implant. The presence of large bony defect at the apical region of the natural tooth and the implant, resulting in a sinus tract and a deep periodontal pocket, was also confirmed with computerized tomography. The treatment procedure included root canal treatment followed by the debridement of the apical bone lesion, and guided bone regeneration. An uneventful healing with acceptable esthetic was observed.  相似文献   
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