Effect of Montelukast on Spinal Cord Ischemia- Reperfusion Injury

AIM

Paraplegia due to ischemia-reperfusion (I/R) injury of the spinal cord is a devastating complication of thoracoabdominal aortic surgery. Cysteinyl leukotrienes are potent mediators of inflammation that are associated with I/R injury. The present study was designed to investigate the role of montelukast, a selective reversible CysLT1 receptor antagonist, on spinal cord I/R injury in an experimental model.

MATERIAL AND METHODS

Twenty-one male Sprague-Dawley rats were randomly assigned to three groups (n=7 per group) as G1 (no aortic occlusion and montelukast administration), G2 (45 min. aortic occlusion; no montelukast administration) and G3 (45 min. aortic occlusion, 10 mg/kg montelukast administration). After neurologic evaluation using the Motor Deficit Index (MDI) score at the 48th hour of reperfusion, lumbar spinal cords were removed for histopathological evaluation and immunohistochemical staining for HSP70, interleukin-6 and myeloperoxidase (MPO).

RESULTS

All rats in the G1 group had a normal neurological status and their MDI score was 0 (p < 0.05). The MDI score of G3 was significantly lower than G2 group (2.8 vs. 5.5; p < 0.05). Vacuolar congestion was found to be significantly lower in G1 than the other groups (p=0.0001). The interleukin-6 receptor level was found to be significantly lower in G3 group than the control group (p=0.013). There was no statistically significant difference found among the groups in terms of the degree of HSP70 and MPO staining.

CONCLUSION

Increased generation of leukotrienes in postischemic organs play an important role in I/R injury. The findings of the current study demonstrated that montelukast improved motor recovery and decreased IL-6 levels in spinal cord I/R injury.

Use of a superficial femoral artery autograft as a femoral vein replacement

Posttraumatic arteriovenous fistulas (AVFs) are common complications of vascular penetrating trauma. Here we present a case of a 59-year-old woman who had a history of gunshot injury 42 years ago causing AVF between superficial femoral artery (SFA) and superficial femoral vein (SFV). SFV was resected. Ipsilateral SFA was used to restore SFV. SFA was reconstituted using a 7-mm polytetrafluorethylene graft. The patient has normal venous and arterial flow at 3- and 15-month follow-up.

Surgical treatment of post-infarct left ventricular pseudoaneurysm with on-pump beating heart technique

Left ventricular pseudo-aneurysms develop when cardiac rupture is contained by pericardial adhesions or scar tissue due to myocardial infarction, surgery, trauma or infection. Left ventricular pseudo-aneurysms are uncommon, difficult to diagnose and prone to cardiac rupture. Urgent surgical repair is recommended. Here we report on a case of a large left ventricular pseudo-aneurysm on the anterolateral wall due to a previous anterior myocardial infarction, and its successful repair using the on-pump beating-heart technique.

Tumescentless endovenous radiofrequency ablation with local hypothermia and compression technique

Introduction

Modern surgical management of chronic venous insufficiency is possible since the development of catheter-based minimally invasive techniques, including radiofrequency ablation (RFA) and the application of colour Doppler sonography. RFA technology requires the use of tumescent anaesthesia, which prolongs the operating time. Instilling tumescent anaesthesia percutaneously below the saphenous fascia is the steepest part of the learning curve. In our study, we compared operative and postoperative results of tumescentless RFA and RFA with tumescent anaesthesia, to investigate the necessity of tumescent anaesthesia.

Methods

A total of 344 patients with Doppler-confirmed great saphenous vein insufficiency underwent RFA between January and December 2012. Patients were divided into two groups according to anaesthetic management. Group 1 consisted of 172 patients: tumescent anaesthesia was given before the ablation procedure, and group 2 contained 172 patients: a local hypothermia and compression technique was used; no tumescent anaesthesia was administered. The visual analogue scale (VAS) was used and ecchymosis scores of the patients were recorded. Clinical examinations were performed at each visit and Doppler ultrasonography was performed in the first and sixth month.

Results

Mean ablation time was significantly lower in group 2 compared to group 1 (7.2 vs 18.9 min; p < 0.05). Skin burn and paresthesia did not occur. The immediate occlusion rate was 100% for both groups. No significant difference was found between the groups in terms of VAS and ecchymosis scores. All patients returned to normal activity within two days. The primary closure rate of group 1 was 98.2% and group 2 was 98.8% at six months, and there was no significant difference between the groups (p > 0.05).

Conclusion

Eliminating tumescent infusion is a desirable goal. Tumescentless endovenous RFA with local hypothermia and compression technique appears to be safe and efficacious. Our technique shortens the operation time and prevents patient procedural discomfort.

Transventricular mitral valve repair in patients with acute forms of ischemic mitral regurgitation

Transventricular mitral valve surgery combined with left ventricular restoration avoids atriotomy and provides a larger operative field. We describe a series of 5 patients in whom we performed transventricular mitral valve repair by various techniques, such as band annuloplasty, papillary muscle reattachment, chordal cutting, and edge-to-edge repair. The more acute forms of ischemic mitral regurgitation, as found in our patients, can coexist with post-myocardial infarction contained rupture or post-myocardial infarction ventricular septal rupture. Because these patients already have an indication for ventriculotomy, concomitant transventricular repair of the mitral valve can render a separate atriotomy unnecessary and thereby shorten the duration of cardiopulmonary bypass. Moreover, in patients with acute presentations, the absence of atrial dilation (this last associated with chronic cases) might make transventricular repair a better choice than the more difficult atrial approach.

Papillary muscle repositioning as a subvalvular apparatus preservation technique in mitral stenosis patients with normal left ventricular systolic function

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.

Relationship of admission neutrophil-to-lymphocyte ratio with in-hospital mortality in patients with acute type I aortic dissection

AIM

Acute aortic dissection is a life-threatening cardiovascular emergency. Neutrophil-to-lymphocyte ratio is proposed as a prognostic marker and found to be related to worse clinical outcomes in various cardiovascular diseases. The aim of the present study was to evaluate the relationship between admission neutrophil-to-lymphocyte ratio and in-hospital mortality in acute type I aortic dissection.

MATERIALS AND METHODS

We retrospectively evaluated 123 consecutive patients who had undergone emergent surgery for acute type I aortic dissection. Patients were divided into 2 groups as patients dying in the hospital (Group 1) and those discharged alive (Group 2). All parameters, including neutrophil-to-lymphocyte ratio, were compared between the 2 groups and predictors of mortality was estimated by using multivariate analysis.

RESULTS

A total of 104 patients (79 males, mean age: 55.2 + 14 years) were included in the final analysis. In multivariate analyses, cross- clamp time, cardiopulmonary bypass time, intensive care-unit duration, platelet count, and neutrophil-to-lymphocyte ratio were found to be independent predictors of mortality. Patients with higher neutrophil-to-lymphocyte ratios had a significantly higher mortality rate (hazard ratio: 1.05; 95% CI: 1.01-1.10; P = 0.033). Receiver operating characteristic analysis revealed that using a cut-off point of 8, neutrophil-to-lymphocyte ratio predicts mortality with a sensitivity of 70% and specificity of 53%.

CONCLUSION

This study suggests that admission neutrophil-to-lymphocyte ratio is a potential predictive parameter for determining the in-hospital mortality of acute type I aortic dissection.

Radiofrequency ablation of the great saphenous vein in an elderly patient with co-morbid disease

An 86-year-old male patient with hypertension, Parkinsonism, benign prostatic hyperplasia, cataract and chronic obstructive pulmonary disease had a history of coronary bypass surgery in two veins due to anterior myocardial infarction one year earlier. He presented with pain and feelings of paresthesia below the knee of his left leg, and had fallen twice. He had used compressions and venoprotective medication for two years and had also received physiotherapy but it had not alleviated the symptoms. He had varicose dilatations in the left leg and pigmentation and a recovered venous ulcer scar were present on the medial malleolus. The patient was classed as grade 4 according to the CEAP classification. Because there was no deficiency in the superficial femoral and popliteal veins, the patient was taken for endovenous ablation. He had no pain or sensation of heaviness in the legs on postoperative day 10, and the first, third and sixth months of check up. Endovenous ablation is a procedure that increases the quality of life and comfort in elderly patients, with minimal pain. Radiofrequency catheter procedures have proven to be more successful in patients of all age groups than procedures such as standard surgery and foam therapy.

Efficacy of iloprost and montelukast combination on spinal cord ischemia/reperfusion injury in a rat model

Background

The thoracic or thoracoabdominal aortic aneurysm surgery may cause spinal cord ischemia because of aortic cross-clamping and may result in severe postoperative complications caused by spinal cord injury. Ischemia/reperfusion injury may directly or indirectly be responsible for these complications. In this study we sought to determine whether combination of iloprost and montelukast can reduce the ischemia/reperfusion injury of spinal cord in a rat model.

Methods

Medulla spinalis tissue concentrations of interleukin-6 (IL-6), myeloperoxidase (MPO) and heat shock protein 70 (HSP-70) were determined in 3 groups of Spraque Dawley rats: control group (operation with cross clamping and intraperitoneal administration of 0.9% saline, n = 7), sham group (operation without cross clamping, n = 7), and study group (operation with cross-clamping and intraperitoneal administration of iloprost (25 ng/kg) and montelukast (1 mg/kg), n = 7). The abdominal aorta was clamped for 45 minutes, with a proximal (just below the left renal artery) and a distal (just above the aortic bifurcation) clip in control and study groups. Hindlimb motor functions were evaluated at 6, 12, 24, and 48 hours using the Motor Deficit Index score. All rats were sacrificed 48 hours after the procedure and spinal cord tissue levels of myeloperoxidase, interleukin-6, and heat shock protein (HSP-70) were evaluated as markers of oxidative stress and inflammation. Histopathological analyses of spinal cord were also performed.

Results

The tissue level of HSP-70 was found to be similar among the 3 groups, however, MPO was highest and IL-6 receptor level was lowest in the control group (p = 0.007 and p = 0.005; respectively). In histopathological examination, there was no significant difference among the groups with respect to the neuronal cell degeneration, edema, or inflammation, but vascular congestion was found to be significantly more prominent in the control group than in the sham or in the study group (p = 0.05). Motor deficit index scores at 24 and 48 hours after ischemia were significantly lower in the study group than in the control group.

Conclusion

This study suggests that combined use of iloprost and montelukast may reduce ischemic damage in transient spinal cord ischemia and may provide better neurological outcome.

Effect of heparin on neuroprotection against spinal cord ischemia and reperfusion in rats

BACKGROUND

Paraplegia due to ischemia/reperfusion (I/R) injury of the spinal cord is a devastating and undesired complication of thoraco-abdominal aortic surgery. Unidentified clots cause a variety of thromboembolic events and deteriorate the severity of ischemia. We investigated the effect of the degree of anticoagulation on spinal cord I/R injury and whether heparin is protective against I/R injury beside its anticoagulant properties.

MATERIALS AND METHODS

Twenty-eight rats were randomly assigned to four groups (n=7 per group) as G1 (no aortic occlusion and heparin administration), G2 (45 min aortic occlusion; no heparin administration), G3 (45 min aortic occlusion; 400 IU/kg heparin to keep activated clotting time (ACT) level around 200 sec), and G4 (45 min aortic occlusion; 800 IU/kg heparin to keep ACT level around 600 sec). After neurologic evaluation at the 48th hour of reperfusion, lumbar spinal cords were removed for histopathologic evaluation and immunohistochemical staining for HSP70 (heat shock protein 70), interleukin-6 and myeloperoxidase (MPO).

RESULTS

The Motor Deficit Index (MDI) scores were lowest in G1 group (p < 0.05) and the MDI scores of G3 and G4 were significantly lower than G2 group (p < 0.05). The neuronal degeneration in G3 was significantly lower than the other groups, respectively (p = 0.03). Histopathological evaluation showed no significant intergroup differences in terms of the degree of edema and inflammatory response. There was no statistically significant difference found among the groups in terms of HSP70 staining, IL-6 staining or the degree of MPO staining.

CONCLUSIONS

Protection of spinal cord from I/R injury requires a multimodal management. We should not miss out the importance of adequate anticoagulation in thoraco-abdominal surgical procedures. Furthermore, the recently discovered anti-inflammatory property of glycosaminoglycans, including heparin, deserves to be investigated.

Protective effect of heparin in the end organ ischemia/reperfusion injury of the lungs and heart

BACKGROUND

Ischemia/reperfusion (I/R) injury is harmful to the cardiovascular system and is responsible for the inflammatory response and multiple organ dysfunctions. In this study we investigated the effect of activated clotting time level on the aortic cross-clamping triggers a systemic inflammatory response and it effects to lungs and heart.

METHODS

End organ concentrations of interleukin-6 (IL-6), myeloperoxidase (MPO) and heat shock protein 70 (HSP-70) were determined in four groups of Spraque Dawley rats: ischemic control (operation with cross clamping received IP of 0.9% saline at 2 ml/kg n=7) Sham (operation without cross clamping, n=7), heparin (ACT level about 200), High dose heparin (ACT level up to 600) The infrarenal aorta was clamped for 45 minutes by a mini cross clamp approximately 1cm below the renal artery and 1cm iliac bifurcation in all groups without sham group. Heparin was given intraperitoneal (IP) before the procedure. All rats were sacrificed 48 h later. In a second experiment, the effects of I/R on remote organs (lungs and heart) were harvested for analysis. We evaluated tissue levels of myeloperoxidase, interleukin-6, and heat shock protein (HSP-70) were analyzed as markers oxidative stress and inflammation. Histological analyses of the organs were performed.

RESULTS

The lungs paranchymal MPO and HSP-70 levels significantly decreased (p<0.05), but IL-6 level was not significant (p>0.05) in heparinized and high dose heparinized groups when compared to ischemic control group. Histopathological evaluation as edema, cell degeneration, inflammation statistically significantly decreased in both group heparinized and high dose heparinized compared with ischemic control group (p<0.05). The heart paranchymal MPO levels significantly decreased in heparinized and high dose heparinized groups when compared to ischemic control group (p=0.023). IL-6, HSP-70 levels were not significant heparinized and high dose heparinized groups when compared to ischemic control group (p=0.0489, p=0.0143). Histopathological evaluation as degeneration statistically significantly decreased in both group heparinized and High dose heparinized compared with ischemic control group (p=0.005).

CONCLUSION

Heparin decreased remote organs injury on the lung and heart after ischemia/reperfusion of infra-renal section of the body in the rat model. So, we should be balance to act level for avoid to I/R injury per operative and early post operative period as providing ACT level nearly 200.

[Alterations in pulmonary artery pressure following mitral valve replacement]

OBJECTIVES

We sought to evaluate the early postoperative hemodynamics and clinical aspects in patients with moderate to severe pulmonary artery pressure (PAP) who underwent mitral valve replacement (MVR) due to isolated mitral valve stenosis.

STUDY DESIGN

Fifty patients (33 women, 17 men; mean age 45.8±11.2) were divided into two groups according to mean PAP levels (PAP <50 mmHg as Group I and PAP >50 mmHg as Group II). PAP and pulmonary capillary wedge pressure (PCWP) values were recorded using Swan-Ganz catheter just before the surgery in the operation theatre. These measurements were repeated after weaning from cardiopulmonary bypass, at 1, 12 and 24 hours. Intubation period in the intensive care unit, need for inotropic agents in the pre-and postoperative course, and mortality and morbidity data were also evaluated. Transthoracic echocardiography was used to measure PAP at the postoperative 24th hour and at the 2nd month after the surgery.

RESULTS

Mean PAP decreased significantly in both groups compared with basal levels. The regression was higher in Group II than Group I. Decrease in PCWP was more significant in Group II. PAP had decreased similarly in both groups according to the postoperative 24th hour echocardiographic evaluation; however, at the postoperative second month follow-up, the decrease in PAP was more significant in Group II.

CONCLUSION

Pulmonary arterial and left atrial pressures significantly decreased in the early periods when the stenosis was alleviated in the isolated mitral stenosis cases with moderate or high PAP levels. This study demonstrates the increased morbidity in patients with higher PAP levels undergoing surgery. It seems that moderate PAP levels do not have a negative influence on postoperative outcomes.

[The effects of implanted valve sizes on ventricular hypertrophy in aortic stenosis]

OBJECTIVE

We aimed to study the effects of the valve sizes according to body surface area on aortic gradient and ventricular hypertrophy in the cases of aortic valve replacement due to isolated aortic stenosis.

METHODS

Between January 2006 and April 2007, patients (12 men, 15 women; totally 27) followed up prospectively with echocardiography fourth and sixth month postoperatively. The patients were divided into two groups according to the prosthetic aortic valve diameters (19-21 mm vs 23-25 mm). The primary endpoints between the two groups (aortic regurgitation, left ventricular mass index and transvalvular gradient measured by color and continuous wave Doppler) were compared. Fischer exact test and Mann-Whitney U test were used for intergroup comparison whereas intragroup analysis was done with Freidman test.

RESULTS

Mean systolic gradient and left ventricular mass index were significantly reduced in 23 mm and 25 mm valves (p<0.01) in the postoperative follow-up. In addition, especially, decline in the values of left ventricular mass, left ventricular mass index, peak systolic gradient and the mean systolic gradient were found to be significant. These values associated with regression were detectable at the postoperative 4th month, but actual significant regression was observed at the postoperative 6th month (p<0.01). On the other hand, the values obtained for 19 mm and 21 mm valves also showed significant progress (p<0.05).

CONCLUSION

Factors such as age, gender and activity are important in the selection of appropriate valve sizes in aortic valve replacement. However, the patient's body surface is the most important prognostic factor compared to others.

Cardiac valve replacement with mechanical prostheses in patients aged 65 years and over

BACKGROUND AND AIM OF THE STUDY

Recent data regarding the performance of mechanical prostheses in patients aged > or =65 years are scant. Hence, the outcome of mechanical prosthesis implantation in this age group has been retrospectively evaluated.

METHODS

Between January 1990 and October 2002, 253 patients (163 males, 90 females) aged > or =65 years (mean age 68.2 years) underwent aortic valve replacement (AVR) and/or mitral valve replacement (MVR) at the authors' institution.

RESULTS

Among the patients, 94 (37.2%) had MVR, 137 (54.1%) had AVR, and 22 (8.7%) had MVR+AVR. In total, 99 patients (39.1%) had concomitant coronary artery bypass grafting (CABG). The early mortality rate was 11.1%; that for patients aged > or =70 years was greater than that for patients aged 65-69 years (14.5% versus 9.6%, p <0.001). The overall actuarial survival was 91.3 +/- 2.4% at 5 years, 81.1 +/- 4.1% at 8 years, and 73.8 +/- 6.3% at 10 years. Actuarial survival for patients with isolated AVR and MVR at 10 years was 84.7 +/- 6.0% and 61.4 +/- 18.8%, respectively. Actuarial survival at 10 years for patients with isolated valve replacement was 76.1 +/- 8.1%, and 68.7 +/- 10.2% for patients with concomitant CABG (p = 0.680). Actuarial survival at 10 years was 81.3 +/- 6.9% for patients aged 65-69 years, and 50.3 +/- 11.0% for patients aged > or =70 years (p = 0.001). Freedom from a major thromboembolic event was 99.4 +/- 0.7% at five years and 86.3 +/- 6.0% at 10 years, while freedom from hemorrhage was 90.4 +/- 2.6% and 70.3 +/- 6.8%, respectively.

CONCLUSION

Mechanical prostheses can be used in patients aged > or =65 years, with favorable results. However, on the basis of the present findings, patients aged > or =70 years have a reduced early and late survival.

Kallikrein 4 is a Predominantly Nuclear Protein and Is Overexpressed in Prostate Cancer

Kallikreins (KLKs) are highly conserved serine proteases that play key roles in a variety of physiological and pathological processes. KLKs are secreted proteins that have extracellular substrates and function. For example, prostate-specific antigen (or KLK3) is a secreted protein that is widely used as a diagnostic marker for prostate cancer. KLK4 is a recently identified member of the kallikrein family that is regulated by androgens and is highly specific to prostate for expression. Here, we show that the gene product of KLK4, hK4, is the first member of the KLK family that is intracellularly localized. We provide strong evidence that the previously assigned first exon that was predicted to code for a signal peptide that would target hK4 for secretion is not part of the physiologically relevant form of KLK4 mRNA. In addition to detailed mapping of the KLK4 mRNA 5' end by RT-PCR, this conclusion is supported by predominantly nuclear localization of the hK4 protein in the cell, documented by both immunofluorescence and cell fractionation experiments. Furthermore, in addition to androgens, hK4 expression is regulated by estrogen and progesterone in prostate cancer cells. Finally, in situ hybridization on normal and hyperplastic prostate samples in tissue microarrays indicate that KLK4 is predominantly expressed in the basal cells of the normal prostate gland and overexpressed in prostate cancer. These data suggest that KLK4 has a unique structure and function compared with other members of the KLK family and may have a role in the biology and characterization of prostate cancer.

Egr1 signaling in prostate cancer

Egr1 is a multifunctional transcription factor regulating a remarkable spectrum of cellular responses from survival to apoptosis, growth to growth arrest, differentiation to transformation, senescence as well as memory and learning effects. In prostate cancer, Egr1 levels are constitutively high and closely linked to cancer development and progression. This zinc-finger protein is a short-lived, immediate early growth response gene known to be induced by a large number of extracellular stimuli such as irradiation (all wavelengths tested), hypoxia, hyperoxia, chemotherapy agents, and more. Therefore the target genes that Egr1 regulates in prostate cancer cells play an important role in generating many of the cellular responses that characterize these cells. After Egr1 binds to its binding sites on gene promoters, specificity of response is determined by whether Egr1 transcriptionally up- or downregulates the target genes. Expression microarray analyses combined with binding data promise new ways to identify stage specific cancer markers, to aid in patient risk assessment and in therapeutic choices.

Cross-talk between signal transducer and activator of transcription 3 and androgen receptor signaling in prostate carcinoma cells

Interleukin 6 (IL-6) plays important roles in the immune system, hematopoiesis, as well as the growth of various tumors. Androgens are important in the initiation and progression of prostate cancer and their effects are mediated by androgen receptor (AR). Here we present a molecular mechanism for the effects of IL-6 on prostate cancer cells through a cross-talk between IL-6 and AR signaling pathways. IL-6-induced activation of signal transducer and activator of transcription 3 (STAT3) was augmented by AR in the presence of dihydrotestosterone (DHT). In addition, DHT treatment augmented endogenous STAT3-mediated gene expression by IL-6. Conversely, DHT-induced AR activity was increased by IL-6, and a dominant negative form of STAT3 inhibited AR activation. In contrast, DHT-mediated enhancement of STAT3 activation was inhibited by flutamide, an AR antagonist. We provide evidence that these activities are due to direct physical interactions between STAT3 and AR in prostate cancer cells.

Protein inhibitor of activated STAT3 regulates androgen receptor signaling in prostate carcinoma cells

Protein inhibitor of activated STAT3 (PIAS3) is a specific inhibitor of signal transducer and activator of transcription 3 (STAT3). PIAS3 binds to STAT3 and inhibits its DNA-binding activity, and thereby STAT3-mediated gene activation. PIAS1, another member of the PIAS family, was recently shown to interact with the androgen receptor (AR), a nuclear hormone receptor that has an important role in both physiological and pathological processes, and acts as a cofactor for AR. Here we demonstrate that PIAS3 is expressed in prostate cancer cells and its expression is induced in response to dihydrotestosterone (DHT) treatment. Ectopic overexpression of PIAS3 suppressed AR-mediated gene activation induced by DHT-stimulation in LNCaP cells. We provide evidence that these activities were due to direct physical interactions between PIAS3 and AR. These results indicate that PIAS3 acts as a coregulator of AR signaling pathway in prostate cancer cells.

Bovine serum albumin partitioning in an aqueous two-phase system: effect of pH and sodium chloride concentration

The partitioning of bovine serum albumin (BSA) in a polyethylene glycol 3350 (8% w/w)-dextran 37 500 (6% w/w)-0.05 M phosphate aqueous two-phase was investigated at different pHs, at varying concentrations of sodium chloride at 20 degrees C. The effect of NaCl concentration on the partition coefficient of BSA was studied for the PEG-dx systems with initial pH values of 4.2, 5.0, 7.0, 9.0, and 9.8. The NaCl concentrations in the phase systems with constant pH value were 0.06, 0.1, 0.2, 0.3, and 0.34 M. It was observed that the BSA partition coefficient decreased at concentrations smaller than 0.2 M NaCl and increased at concentrations greater than 0.2 M NaCl for all systems with initial pHs of 4.2, 5.0, 7.0, 9.0, and 9.8. It was also seen that the partition coefficient of BSA decreased as the pH of the aqueous two-phase systems increased at any NaCl salt concentration studied.

P53, p15INK4B, p16INK4A and p57KIP2 mutations during the progression of chronic myeloid leukemia

The occurrence of acute transformation during the treatment of chronic myeloid leukemia (CML) is still a poorly understood mechanism. In this disease p53, p16INK4A, p15INK4B, p57KIP2 mutations and p15INK4B/p16INK4A homo/hemizygous deletions were analyzed in the initial diagnosis phase and during the treatment phase of twelve CML cases, in order to establish whether there was a consistent molecular genetic alteration in its progression. During the treatment period, four of twelve cases had blastic crisis. All the mutations observed in p53, p16INK4A and p15INK4B cumulated in three out of four CML cases who had blastic crises. In one case, p53 codon 282 mutation (CGG-->TGG; arg-->trp) were observed in initial diagnosis. Seven months later, G-->C transition in the 3' side of p15 cDNA (778. nucleotide) was observed in the accelerated phase with the same p53 codon 282 mutation. Thirteen months later, this patient died as a result of blastic crisis. The patient in blastic crises in the initial diagnosis phase had a mis-sense point mutation in p16 codon 69 (ACT-->AGT; thr-->ser) and a polymorphism in codon 68 (GCC-->GCG). Six months later, this patient also died. In one case, p53 codon 237 mutation (ATG-->ATA; met-->ile) were observed in the initial diagnosis phase. Then months later, the patient died as a result of blastic crises. No p15INK4B/p16INK4A homo/hemizygous deletion and p57KIP2 gene mutation which was described in the same pathway were observed in CML progression. These results indicate that p15INK4B and p16INK4A gene alterations may have an affect on the progression of CML-like p53 mutation. A correlation was found with the progression of CML and p53, p15INK4B and p16INK4A somatic mutations. Finding p15INK4B and p16INK4A gene alteration as well as p53 mutations may be a prognostic marker in patients with CML.

The importance of visual erotic stimulation in the differential diagnosis of erectile impotence

In this study we aimed to determine the importance of visual erotic stimulation (VES) alone, and in combination with intracavernosal papaverine injection (ICPE) in the differential diagnosis of erectile impotence. Sixty-four patients with erection problems were investigated between June 1992 and January 1994. VES could be the first investigative method in the differential diagnosis of erectile impotence. This will help us in some groups of patients with psychogenic impotence to avoid the application and complications of ICPE. In patients with insufficient erections with VES alone, ICPE must be combined with VES in order to detect the causes of psychogenic erectile impotence more correctly.

Diagnosis of urethral strictures: is retrograde urethrography still necessary?

Different methods are available in the diagnosis and treatment of urethral strictures. True diagnosis is necessary for choosing the most suitable method of treatment and to inform the patient about the method, complications, recurrence rate and costs. In this study we aimed to compare the efficiency, complications and reproducibility of retrograde urethrography with urethroscopy. The retrograde urethrographic (RGU) and urethroscopic findings of 38 male patients were evaluated. Thirty had the same findings with either technique. In 8 patients the RGU was misdiagnosing (p < 0.01). In conclusion, it has been shown that the results of RGU are misleading when it is not combined with urethroscopy and we think that it must not be a routine method in the diagnosis of urethral strictures.