Factors Predicting Febrile Urinary Tract Infection After Ureterorenoscopic Lithotripsy in Pediatric Patients

Introduction: There is no study investigating the factors predicting postoperative febrile urinary tract infection (fUTI) in pediatric patients. We aimed to determine the factors predicting postoperative fUTI in pediatric patients who underwent ureterorenoscopic lithotripsy (URS-L). Methods: Pediatric patients who underwent URS-L due to ureter or kidney stones in our clinic between 2012 and 2019 were analyzed retrospectively. The demographic data, stone characteristics, intraoperative and postoperative data of those with and without postoperative fUTI were compared. Univariable and multivariable binary logistic regression analysis was performed to determine predictors of fUTI. Results: A total of 136 patients were included in the study. Postoperative fUTI developed in 17 patients (12.5%). History of stone surgery, history of UTI, presence of nephrostomy/D-J stent, type of surgery, operation time, length of stay, and presence of complication except fUTI were found to be significantly different in the fUTI group. In the univariate analysis, history of stone surgery, history of UTI, presence of nephrostomy/D-J stent, type of surgery, operation time, and presence of complication except fUTI were determined as factors predicting fUTI. In multivariate analysis, only the history of UTI was identified as an independent predictive factor. Conclusion: In pediatric patients, infectious complications constitute the majority of complications after URS-L. History of UTI is the only independent factor that predicts postoperative fUTI after URS-L.

Analysis of the Causes of Newborn Priapism: A Retrospective Clinical Study

Priapism is a rare condition in the newborn. The aim of this study was to investigate the demographic, etiologic and clinical features of neonatal priapism. We retrospectively analysed the data of 11 patients diagnosed with neonatal priapism in the neonatal intensive care unit between 2000 and 2019. Priapism was defined as an erection in the neonatal period, lasting more than 4 hours. Etiological examinations revealed polycythemia in one (9.09%) patient, D-dimer elevation in three patients, and heterozygous methyltetrahydrofolate 667 gene mutations in one patient. Other patients were considered idiopathic. Detumescence was achieved in all 11 (100%) patients during the follow-up period. The median hospitalization duration was 6 (IQR [4, 8]; range, 2-9) days. The median follow-up duration was 38 (IQR [30, 42]; range, 13-94) months for patients followed-up in our hospital after discharge. Neonatal priapism is a rare condition. Successful treatment results can be achieved with conservative methods. Data acquired from our study showed that diseases with a tendency to hypercoagulation belong to the etiology by damaging penile microcirculation and make the response to conservative treatment more challenging.

Can shock wave lithotripsy lead to impaction of ureteral stones?

BACKGROUND

One of the underlying reasons for shock wave lithotripsy (SWL) resistance is the ureteral stone impaction. This study aimed to investigate the accuracy of the hypothesis, suggesting that SWL per se can be the reason for ureteral stone impaction.

METHODS

One hundred and seventy-six patients were enrolled in the study. Data of the patients (N.=50) treated with SWL and subsequent semirigid ureteroscopic laser lithotripsy (SULL) in our center between January 2014 and January 2020 were retrospectively reviewed compared with the data of the patients (N.=126) who underwent SULL without prior SWL treatment during the same period. Patients reported to have ureteral stone impaction during SULL were compared with those without stone impaction in terms of demographic parameters, stone characteristics and clinical data, including symptom duration and presence or absence of SWL history.

RESULTS

The success rate of SULL was determined as 80.1% (141/176). Univariable analysis revealed statistically significant differences between the patients with and without stone impaction concerning stone diameter, stone volume, pre-SULL SWL history, symptom duration and ureteral wall thickness (UWT). Multivariable logistic regression analysis revealed that symptom duration and UWT were independent predictive factors for ureteral stone impaction.

CONCLUSIONS

Symptom duration and UWT are independent predictors of ureteral stone impaction. Symptom duration and UWT should be considered during treatment planning and informed consent process before proceeding with SULL.

Efficacy of combination therapy with biofeedback and dapoxetine in lifelong premature ejaculation treatment: a prospective randomized study

PURPOSE

Premature ejaculation (PE) is a common sexual dysfunction that significantly affects the quality of life of the patient and their partner. We aimed to compare the efficacy and safety of the combination therapy with biofeedback-guided pelvic floor exercise therapy (BFT) and dapoxetine 30 mg.

METHODS

Sixty-five patients diagnosed with lifelong PE were included in the study. Patients were divided into three groups as BFT, dapoxetine 30 mg and a combination of BFT and dapoxetine 30 mg. The patients were compared with the intravaginal ejaculatory latency time (IELT) pre-treatment and post-treatment 1st and 3rd months.

RESULTS

The mean IELTs of the patients in Group 1 were 40 s in pre-treatment, 115 s at the end of the 4th week and 140 s at the end of the 12th week. The IELT values of the patients in Group 2 were 40 s in pre-treatment, 145 s in the 4th week and 170 s in the 12th week. The IELT values were calculated in Group 3 as 42.5 s in pre-treatment, 185 s in the 4th week and 205 s in the 12th week When the IELT was statistically compared between the groups at 1st and 3rd months, the duration in the combination group was found to increase significantly (p < 0.001).

CONCLUSION

Combination therapy with BFT and dapoxetine 30 mg in lifelong PE treatment is a good alternative with a low side effect profile and acceptable continuous efficiency.

Is biofeedback-assisted pelvic floor muscle training superior to pelvic floor muscle training alone in the treatment of dysfunctional voiding in women? A prospective randomized study

Purpose:

To compare the effectiveness of biofeedback-assisted pelvic floor muscle training (PFMT) and PFMT alone on voiding parameters in women with dysfunctional voiding (DV).

Materials and Methods:

The patients in group 1 (34 patients) were treated with biofeedback-assisted PFMT, and the patients in group 2 (34 patients) were treated with PFMT alone for 12 weeks. The 24-hour frequency, average voided volume, maximum urine flow rate (Q_max), average urine flow rate (Q_ave), post-void residual urine volume (PVR), and the validated Turkish Urogenital Distress Inventory (UDI-6) symptom scores were recorded before and after 12 weeks of treatment.

Results:

At the end of treatment sessions, the Q_max and Q_ave values of the patients in group 1 were significantly higher than those in group 2, and the PVR in the patients in group 1 was significantly lower than those in group 2 (p=.026, .043, and .023, respectively). The average UDI-6 symptom scores of the patients in group 1 were significantly lower than those in group 2 (p=.034). Electromyography activity during voiding, in group 1 was significantly lower than in group 2 (41.2 vs. 64.7, respectively, p=.009).

Conclusion:

Biofeedback-assisted PFMT is more effective than PFMT alone in improving clinical symptoms, uroflowmetry parameters, and EMG activity during voiding.

Desires and attitudes of outpatients and physicians regarding the use of teleurology during the pandemic: a prospective survey study

OBJECTIVE

It is not known to date how many patients admitted to urology outpatient clinics are willing to use telemedicine. We aimed to investigate knowledge levels and attitudes concerning the utilization of teleurology by patients applying to urology outpatient clinics.

METHODS

This prospective multicentre survey study included 334 patients aged 18-65 years who applied to an urology outpatient clinics. The patients were asked questions about their attitudes and expectations regarding teleurology. Diseases were divided into seven subgroups due to the broad spectrum of diagnoses. Physicians' and patients' opinions on whether it was possible to manage the current medical condition via teleurology were recorded.

RESULTS

69.5% of patients stated that they had sufficient technical skills to use teleurology by themselves for medical examination. 55.4% of patients and 78.4% of physicians responded that the existing complaints were suitable for teleurology. Both patients and physicians deemed genital system diseases and urinary tract infections suitable for teleurology (p<0.001, p<0.001 for physicians, and p<0.001, p<0.001 for patients), whereas urine transport, storage and emptying disorders (p=0.003) and benign prostatic hyperplasia (p=0.029) were deemed to be suitable for teleurology only by the physicians.

CONCLUSION

Our study shows that (i) the majority of our patient population has a telecommunications infrastructure suitable for teleurology, (ii) teleurology has aroused interest among patients, particularly during the pandemic period, and (iii) physicians and patients have high expectations that the problem can be solved with teleurology in suitable patients.

The role of penile elastography in the evaluation of erectile dysfunction in patients with chronic obstructive pulmonary disease

Introduction

In this study, we aimed to measure the change in penile stiffness by evaluating corpus cavernosum (CC) with shear wave elastography (SWE) in patients with chronic obstructive pulmonary disease (COPD).

Material and methods

Seventy outpatient patients aged 50–80 years who were diagnosed with COPD were evaluated using SWE. Patients were divided into 2 groups according to the International Index of Erectile Function-5 (IIEF-5) questionnaire (IIEF-5 >17: Group A, IIEF-5 <17: Group B). The measurements were made in both transverse and longitudinal sections.

Results

The mean age of the patients was 60 ±7.9 years. The duration of COPD was significantly higher in Group B than in Group A (p = 0.003). The mean SWE values of right transverse mid-portion of corpus penis (RTM) and left transverse mid-portion of corpus penis (LTM) in Group B (21.1 ±5.6 kPa and 20.8 ±4.8 kPa, respectively) were significantly higher than in Group A (15.2 ±2.3 kPa and 15.8 ±2.7 kPa, respectively); (p <0.001 and p <0.001, respectively). There was a significant negative correlation between IIEF-5 scores and the duration of COPD (p <0.05). There was a significant negative correlation between IIEF values and RTM and LTM values of the patients (p <0.05 and p <0.05, respectively). There was a significant positive correlation between the duration of COPD and both RTM and LTM values (p <0.05 and p <0.05, respectively).

Conclusions

In our study, according to the SWE findings, we showed the effect of systemic changes created by COPD on penile tissue and the negative effect of this on erectile function in patients.

The relationship of serum testosterone levels with the clinical course and prognosis of COVID-19 disease in male patients: A prospective study

Background

A potential role of testosterone among sex hormones has been hypothesized in identifying sex‐related differences in the clinical consequences of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) infection. Due to the high global prevalence of hypogonadism, the relationship between hypogonadism and SARS‐CoV‐2 infection outcomes deserves an in‐depth study.

Objective

The present study aimed to investigate the relationship of serum testosterone with other laboratory parameters on the prognosis of coronavirus disease‐19 (COVID‐19) in male patients with COVID‐19 diagnosis.

Materials and methods

This prospective cohort study included 358 male patients diagnosed with COVID‐19 and 92 COVID‐19 negative patients admitted to the urology outpatient clinics as a control group. The COVID‐19 patients were divided into groups according to prognosis (mild‐moderate and severe group), lung involvement in chest computed tomography (<50% and >50%), intensive care unit needs, and survival.

Results

The measured serum total testosterone level of the COVID‐19 patients group was found to be significantly lower than that of the control group (median, 140 ng/dl; range, 0.21–328, 322 ng/dl; range, median, 125–674, p < 0.001, respectively). The serum TT levels were statistically significantly lower in severe COVID‐19 patients compared to mild‐moderate COVID‐19 patients (median, 85.1 ng/dl; range, 0.21–532, median, 315 ng/dl; range, 0.88–486, p < 0.001, respectively), in COVID‐19 patients in need of intensive care compared to COVID‐19 patients who did not need intensive care (median, 64.0 ng/dl; range, 0.21–337, median, 286 ng/dl; range, 0.88–532 p < 0.001, respectively), and in COVID‐19 patients who died compared to survivors (median, 82.9 ng/dl; range, 2.63–165, median, 166 ng/dl; range, 0.21–532, p < 0.001, respectively).

Discussion and conclusion

Our data are compatible with low TT levels playing a role on the pathogenesis of the disease in Covid‐19 patients with poor prognosis and a mortal course and may guide clinicians in determining the clinical course of the disease.

Comparison of Perioperative, Oncological, and Functional Outcomes of Three-Dimensional Versus Robot-Assisted Laparoscopic Radical Prostatectomy: A Preliminary Study

Background: Radical prostatectomy (RP) is the first-line treatment modality for prostate cancer and can be performed using retropubic or minimally invasive techniques. New technologies such as the da Vinci robotic system and three-dimensional (3D) laparoscopic imaging system have been developed to overcome the challenges of conventional laparoscopy. This study aimed to compare the perioperative, oncological, and functional outcomes of robot-assisted laparoscopic RP (RALP) and 3D laparoscopic RP (3D LRP). Materials and Methods: The study was approved by the local ethics committee and included 65 patients (38 RALP, 27 3D LRP) who underwent RP with the diagnosis of localized prostate cancer between May 2019 and January 2020. All demographic, clinical, perioperative, pathological, and postoperative variables were recorded. Results: There was no statistically significant difference between the two groups in terms of preoperative patient characteristics. The mean operative times of the RALP and 3D LRP groups were 135.74 ± 11.51 and 165.37 ± 15.86 minutes, respectively, with a statistically significant difference between the two groups (P = .001). The mean estimated blood loss was 237 ± 71 mL in the RALP group and 257 ± 54 mL in the 3D LRP group, with no statistically significant difference between the two groups (P = .236). In the 6 months of follow-up, there was no statistically significant difference between the two groups in terms of biochemical recurrence, continence, and potency. Conclusion: RALP and 3D LRP have similar perioperative, short-term oncological and functional outcomes other than the operative time. There is a need for prospective, randomized studies with larger populations evaluating long-term oncological and functional outcomes.

Factors predicting duration and success of semirigid ureteroscopy for ureteral stones in different localizations

OBJECTIVE

In this study, we aimed to determine the factors predicting the duration and successof semirigid ureteroscopy performed for the treatment of ureteral stones in different localizations. MATERIALS AND METHODS: Medical records of the patients whom under went semirigid ureteroscopy for urolithiasis in our centre between January 2015 and December 2019 were retrospectively reviewed. The study group composed of 170 patients and divided into three subgroups; of which 54 in proximal ureter (31.8%), 51 in the mid (30 %) and 65 (38.2%) in the distal ureter. Predictive factors of semirigid ureteroscopy duration and success were determined by performance of correlation analysis and multivariate analysis.

RESULTS

Overall stone-free rate was calculated as 78.8%. Success rates for proximal, mid and distal ureteral stones were 72.2% (39/54 patients), 74.5% (38/51 patients) and 87.7% (57/65 patients), respectively. Complications were present in 19 patients (11.2%). Multivariate analysis indicated that stone diameter and stone burden independently affected the stone-free rate. Statistically significant negative correlation was determined between success of the procedure and stone diameter, stone burden, impaction and more proximal stone localization. While there was a statistically significant positive correlation between duration of procedure and stone burden, diameter, impaction, historyof ipsilateral ureteroscopy and more proximal stone localization, there was negative correlation between duration of procedure and stone-free status. CONCLUSION: We conclude that stone diameter, stone burden, impaction and more proximal stone localization are common factors affecting both duration and success of semirigid ureteroscopy. In addition, stone size and stone burden were determined as independent markers of stone-free status.

Surgical results in penile fracture: Our single center experience

INTRODUCTION

Penile fracture arises as a result of a unilateral or bilateral rupture of the tunica albuginea of the corpus cavernosum. It is a rare condition that requires urgent surgical intervention. In this study, we aimed to determine the effectiveness of surgical treatment in penile fracture and its effect on complications.

METHODS

The data of 21 patients who were admitted to the emergency department of our clinic between 2012 and 2019 and underwent emergency surgical repair with the diagnosis of penile fracture were collected retrospectively. The diagnosis of penile fracture was established by anamnesis and physical examination. Age, etiology, duration from trauma to surgery, physical examination findings,length and localization of the tunica albuginea defect, length of hospital stay, and postoperative first-, third- and sixth-month follow-up results were analyzed. Erectile function was evaluated using the International Index of Erectile Function (IIEF-5). Complications such as penile curvature, penile nodule and painful erection were evaluated.

RESULTS

The mean age of the patients was 36.8 ± 8.3 years. The most common reason of penile fracture was manually bending the penis for detumescence. All patients underwent surgery. The mean duration from trauma to surgery was 7.6 ± 3.1 h. The mean length of the tunica albuginea defect was 11 ± 2.5 mm. The mean length of hospital stay was 2.5 ± 0.5 days. The mean IIEF-5 scores in the postoperative first, third and sixth months were 20.5 ± 2.6, 22 ± 2.2, 22.1 ± 1.7, respectively.

CONCLUSION

Penile fracture is a urological emergency, and timely surgery is an effective treatment method for preventing postoperative complications.

The utility of De Ritis Ratio in predicting prognosis in testicular cancer

OBJECTIVE

We aimed to investigate the possible association between testicular cancer prognosis and De Ritis ratio (AST/ALT).

METHODS

The medical records of all patients who underwent radical inguinal orchiectomy at a single tertiary in Istanbul, Turkey between 2006 and 2017 were retrospectively analyzed. Investigated parameters included patients' demographics, complete blood count and blood biochemistry results, pathology results, treatment schemes, imaging results, and survival. De Ritis ratio was calculated as follows: AST/ALT.

RESULTS

A total of 171 patients with a mean age of 32.6 ± 10.1 years were included in the study. 73 patients had T1, 83 had T2, 13 had T3 and 2 had T4 disease. Rete testis invasion was detected in 74 patients (43.3 %) as well as lymphovascular invasion in 93 (54.4 %) and tunica albuginea invasion in 80 (46.8 %) patients. The cut-off value for AST/ALT was set at 1.35 [Area Under Curve (AUC): 0.791 with a sensitivity of 80 % and specificity of 73 %]. No statistically significance was observed between patients with and without elevated AST/ALT according to rete testis invasion, lymphovascular invasion, tunica albuginea invasion, and tunica vaginalis invasion (p = .25, p = .63, p = 1.0 and p = 1.0, respectively). 28.2 % of patients with seminoma had AST/ALT > 1.35 however 41.9 % of patients with non-seminoma pathology had AST/ALT > 1.35 (p = .078). Mean estimated survival time of patients with AST/ALT > 1.35 was higher than those with AST/ALT < 1.35, 91.8 versus 70.4 months, p < .001). As seen in Kaplan-Meier analysis elevated AST/ALT is associated with early-term mortality.

CONCLUSION

De Ritis ratio was shown to be significantly associated with unfavorable prognosis. De Ritis ratio might serve as a prognostic biomarker in testicular tumor besides well-known tumor markers such as beta-human chorionic gonadotropin (hCG), alpha-fetoprotein (AFP) and lactate dehydrogenase (LDH).

Gasless robotic perineal radical prostatectomy: Experience of the first 12 cases

OBJECTIVE

To present our results of first 12 patients on whom we performed gasless robotic perineal radical prostatectomy (r-PRP).

METHODS

We performed gasless r-PRP on 12 patients between August 2018 and October 2018. Multiparametric magnetic resonance imaging was performed forall patients to exclude local advanced disease. Demographic characteristics, technical details, and intra and postoperative data were analyzed.

RESULTS

The mean age of the patients was 62.6 ± 6years. The mean body mass index of the patients was 27 ± 4 kg/m2. Four patients had a history of major abdominal surgery. The mean preoperative prostate-specific antigen (PSA) was 7.4 ± 2.5 ng/mL. The mean prostate volume was 40 ± 10.2 cc. The mean perineal dissection time was 45.6 ± 5.8 minutes. The mean console time and total operative time were 117.8 ± 28.1 and 163.3 ± 30.7 minutes, respectively. The mean urethral catheter removal time was 9.2 ± 1.9 days. The immediate continence rate was 25% after the urethral catheter removal and the continence rate was 75% and 91.67% at the 3rd and 6th month follow-up, respectively.

CONCLUSIONS

Gasless r-PRP is an efficient and safe method in prostate cancer surgery. However, prospective randomized and comparative studies are required with large patient series.

Robotic perineal radical prostatectomy in a patient with a pre-existing three piece inflatable penile prosthesis

Radical prostatectomy (RP) is the primary and standard treatment for localized prostate cancer. As in many surgical procedures, RP can now be accomplished through minimally invasive methods. RP in a patient with a pre-existing 3-piece inflatable penile prosthesis (IPP) is an exceptional condition and involves coping with many difficulties. In this case report, we aimed to present a patient with pre-existing 3-piece IPP for whom we successfully performed robotic perineal RP (r-PRP).

Splenic Injury During Percutaneous Nephrolithotomy: A Case Report of a Rare Complication

Percutaneous nephrolithotomy has often been the preferred method for large and complex kidney stones. During percutaneous access to the collecting system, we encounter organ injuries due to anatomic neighborhoods. However, splenic injury is a relatively rare complication. We aimed to report how the complication process was managed conservatively in our case with transsplenic access. Then, a brief literature review on management strategy in similar conditions is highlighted. 

Partial nephrectomy in horseshoe kidney: Primary carcinoid tumor

Primary neuroendocrine carcinoma of the kidney is a rarely observed clinical condition because neuroendocrine cells are not found in kidney parenchyma. It’s not clinically and radiologically possible to distinguish from other kidney tumors. Incidence with horseshoe kidney anomaly, it should be considered as a definitive diagnosis for the patients with this condition. In this case report, we reported about a carcinoid tumor in horseshoe kidney in a 37-year-old woman.

Comparison of cold-knife optical internal urethrotomy and holmium:YAG laser internal urethrotomy in bulbar urethral strictures

Introduction

To compare the results of cold-knife optical internal urethrotomy (OIU) and Holmium:YAG laser internal urethrotomy (HIU) in primary bulbar urethral strictures.

Material and methods

A total of 63 patients diagnosed with primary bulbar urethral stricture between August 2014 and September 2015 were assigned to the OIU (n = 29) and HIU (n = 34) groups. The demographic variables, biochemistry panels, and preoperative and postoperative uroflowmetry results including the maximum flow rate (Qmax) and mean flow rate (Qmean) values, retrograde urethrography, and diagnostic flexible urethroscopy findings were recorded prospectively. Demographic features and preoperative values were not statistically different between groups (p >0.05). Mean surgical times were 18.4 ±2.3 min for OIU and 21.9 ±3.8 min for HIU groups, which was statistically significant (p <0.05). There was no significant difference in complication rates in both groups (p = 0.618).

Results

Postoperative Qmax values were increased in both groups even though postoperative Qmax values were not significantly different between the two groups in the short- and long-term results at 3, 6, and 12 months (p >0.05). There was no recurrence in the first 3 months in either group. The urethral stricture recurrence rate up to month 12 was not statistically significant for the OIU group (n = 6, 20.7%) as compared to the HIU group (n = 11, 32.4%; p = 0.299).

At follow-up, the SFR and IFR was 96% and 88% at 3-months, and 82% and 71% at 12-months, respectively (p <0.001). While almost three-quarters of patients were stone and infection free at 12-months, the majority of those with stones recurrence also had recurrence of their UTI.

Conclusions

HIU is an alternative method to OIU, and it has similar success rates in the treatment of short segment bulbar urethral strictures.

Nasal mucoadhesive delivery systems of the anti-parkinsonian drug, apomorphine: influence of drug-loading on in vitro and in vivo release in rabbits

Lyophilized polyacrylic acid powder formulations loaded with apomorphine HCl were prepared and the influence of drug loading on in vitro release and in vivo absorption studied after intranasal administration in rabbits. These formulations prepared with Carbopol 971P, Carbopol 974P and polycarbophil sustained apomorphine release both in vitro and in vivo. The in vitro release rate and mechanism were both influenced by the drug loading. There was no large influence of drug loading on the time to achieve the peak (Tmax) for a particular polymer, but Tmax differed between different polymers. For a particular drug loading, the Tmax from Carbopol 971P was the slowest compared with that for Carbopol 974P and polycarbophil; however, only the Tmax from Carbopol 971P loaded with 15% w/w of apomorphine was significantly longer than polycarbophil of similar drug loading (P=0.0386). The trend further observed was that increasing drug loading led to increased peak plasma concentration and area under the curve (AUC). In the second part of this study, a mixture containing an immediate release component and sustained release formulation was administered in an attempt to increase the initial plasma level, as this could be therapeutically beneficial. Only one peak plasma concentration was observed and the initial plasma concentrations were no higher than those obtained with solely sustained release formulation. The Tmax, the peak plasma drug concentration (Cmax) and AUC from the lactose-containing formulation were lower than the formulation without lactose but the differences were only marginally statistically significant for Cmax (P=0.0911) and AUC (P=0.0668), but not Tmax (P=0.2788).

Catechol is the major product of salicylate hydroxylation in 1-methyl-4-phenylpyridinium ion treated rats

Salicylate hydroxylation using hydroxyl free radicals results into formation of 2,3-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid and catechol. Inspite of the fact that in vitro experiments have shown that catechol is a minor product, we have shown by these in vivo studies that it is a substantial product. Since catechol as well as 2,3-dihydroxybenzoic acid have not been found to be produced enzymatically from salicylates, they appear useful as in vivo indicators for monitoring hydroxyl free radicals. Administration of 1-methyl-4-phenylpyridinium ion (MPP+) to rat striatum using microdialysis results into the formation of hydroxyl radicals. Salicylate perfusion enables the estimation of the three derivatives cited above. They increased significantly after MPP+ administration in comparison to the baseline values, with catechol being the most significant. The maximum amounts were achieved 60 min after MPP+ administration, and the mean percentage increase at this time point were 83.1% for 2,3-DBA (n = 6, P = 0.005), 81.25% for 2,5-DBA (n = 6, P = 0.011) and 1228.8% for catechol (n = 4, p = 0.00008). MPP+ caused substantial decrease of dopamine metabolites. Dihydroxyphenylacetic acid decreased to 13% and homovanillic acid to 11.4%. We conclude that catechol is an important indicator of hydroxyl free radical formation in this animal model which is well suited to study the role of free radicals in Parkinsonism.

Distribution of apomorphine enantiomers in plasma, brain tissue and striatal extracellular fluid

Steady-state concentrations of apomorphine enantiomers were measured in the extracellular fluid collected from rat brain striatum by microdialysis. The free and total concentrations of both enantiomers were also measured in plasma as well as the total concentrations in different brain regions (striatum, cortex and cerebellum). We noticed no regional difference in the total concentrations of the two enantiomers. The extracellular concentrations were much lower, amounting to 8% for R(-)-apomorphine and 4% for S(+)-apomorphine, of the total brain tissue concentrations. The microdialysis samples contained 12 times more (R(-)-apomorphine and 5 times more S(+)-apomorphine than the free apomorphine measured in plasma. The extracellular concentrations of R(-)-apomorphine (129 +/- 20 pmol/ml) were significantly higher (P = 0.001, n = 6), than those of S(+)-apomorphine (70 +/- 10 pmol/ml). These results indicate that both enantiomers of apomorphine concentrate equally in brain cells, and that a stereoselective uptake system could operate for R(-)-apomorphine at the blood-brain barrier level.

Preservative-mediated changes of the surface properties of Escherichia coli

The effectiveness of two commonly used preservatives, sodium benzoate and potassium disulfite, was evaluated in terms of their bactericidal activity and capacity to induce changes in the surface properties of Escherichia coli isolated from commercial food preserves. Preservative treatment over a five-week test period resulted in controlling the multiplication of these organisms and causing a decline in cell-surface hydrophobicity, hemagglutinating ability and adherence capacity to rat intestinal cells of E. coli isolates. A loss in motility was also exhibited.

Apomorphine pharmacokinetics in parkinsonism after intranasal and subcutaneous application

Apomorphine was administered subcutaneously and intranasally to 7 patients suffering from Parkinsonism with 'on-off' problems. This comparative pharmacokinetic study showed that the two routes of administration are comparable with respect to absorption kinetics. Apomorphine is rapidly absorbed when administered intranasally or subcutaneously with an absorption half life of 8.6 min and 5.8 min, respectively. The high rate of absorption is also reflected by the time for the plasma concentration to peak (tmax) and the lag times. The tmax was 23 min for intranasal route and 18 min for the subcutaneous route while the lag times were 2.8 min and 3.9 min, respectively. The bioavailability of intranasal apomorphine compared to the subcutaneous route amounted to 45%. After intranasal and subcutaneous administrations, the elimination half life of apomorphine amounted to 31 min and 27 min, respectively.

Stability of apomorphine in plasma and its determination by high-performance liquid chromatography with electrochemical detection

Dilute solutions (50 ng/ml) of apomorphine in plasma are unstable at 37 degrees C and pH 7.4. The chemical half-life is only 39 min. Mercaptoethanol (0.01%) is effective in stabilizing these samples while sodium metabisulphite (1%), which is generally used, is not effective. Biological samples are extracted with diethyl ether (recovery 96.5%) and analysed using HPLC with coulometric detection (oxidation potential 0.25 V). The stationary phase employed was C18 material (4 microns) and the mobile phase was phosphate buffer (pH 3)-acetonitrile (70:30, v/v). The flow-rate was 1.8 ml/min. This bioanalytical method presents a reliable tool for pharmacokinetic studies in man.

Epstein-Barr virus and other herpesvirus infections in Kawasaki syndrome

Epstein-Barr virus (EBV), a possible cause of Kawasaki syndrome (KS), is not pathenogenically associated with KS in Hawaii. The prevalence of EBV capsid antibody in KS patients was found not to differ significantly from that in controls, and the antibody response in those infected with EBV was the same as that in other children similarly infected. No EBV was isolated from acute-phase patients. All patients with capsid antibody at the onset of KS also had Epstein-Barr nuclear antigen antibody: 36 patients developed antibody within 3 months after onset of KS; in 10, EBV infection could have been coincidental with the disease. Cytomegalovirus (CMV) was isolated from 9 patients with KS and 10 controls. A similar number of controls and patients had antibody to human herpesvirus 6 (HHV6); one patient seroconverted. None of the herpes viruses (EBV, CMV, HHV6, varicella-zoster virus, or herpes simplex virus) plays a unique or dominant role in the etiology or pathogenesis of KS in Hawaii.