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Barry A Kogan

Publications and source records attributed to Barry A Kogan.

At least 19 recordsLinked to original sources
PubMed2007

Effect of bilateral in vivo ischemia/reperfusion on the activities of superoxide dismutase and catalase: response to a standardized grape suspension.

PURPOSE: Ischemia/reperfusion (I/R) is a major etiological factor in the bladder dysfunctions observed in men with lower tract obstruction, women with postmenopausal incontinence and with aging. A standardized grape suspension protects the rabbit urinary bladder from both the contractile dysfunctions and the morphologic changes mediated by I/R. Using a model of in vivo bilateral ischemia/reperfusion, the current study investigated the effect of this grape suspension on the endogenous antioxidant defense systems. MATERIALS AND METHODS: 24 NZW rabbits were separated into 6 groups of 4. Groups 1-3 were treated by gavage with aqueous grape suspensions; groups 4-6 received sugar-water vehicle. Groups 3 and 6 were controls. Groups 1 and 4 were subjected to bilateral ischemia for 2 h (I). Groups 2 and 5 underwent bilateral ischemia for 2 h and reperfusion for 1 week (I/R). For all rabbit bladders, the muscle and mucosa were separated by blunt dissection and analyzed separately. The effects of the various treatments on bladder antioxidant systems of cytoplasmic superoxide dismutase (Cu-Zn superoxide dismutase; SOD), and catalase (CAT) were evaluated. RESULTS: The standardized grape suspension up-regulated both SOD and CAT activity of bladder muscle and mucosa in control animals. There were few differences in the grape suspension treated animals after ischemia, and in general the activities decreased following I/R. CONCLUSIONS: Increases of SOD and CAT activity in control animals as a result of grape suspension suggest a greater antioxidant capacity. This increase in the antioxidant defense system may explain the increased protection of grape suspension in the face of ischemia and I/R. However, the activities of both enzyme systems decreased in the smooth muscle subjected to I/R showing that reperfusion damages these systems probably via oxidation damage to the enzymes themselves.

Animals↗
PubMed2006

Short-term catheterization after TIP repair in distal hypospadias: who are the best candidates?

Over the last decade, tubularized incised plate (TIP) urethroplasty has become the first choice of surgical technique in patients with distal hypospadias. Despite the excellent cosmetic and functional results, prolonged catheterization (7-14 days) remains the main disadvantage of the TIP repair. In this study, we investigated the outcomes of the short-term catheterization in children with distal hypospadias in order to elucidate any relationship between the length of catheterization and the patients' age, meatal localization and postoperative complication rates. The charts of 183 patients who underwent TIP repair for distal hypospadias in two different centers were reviewed retrospectively. Patients were grouped based on their catheter removal time (before 24 h vs. after 24 h) and the toilet status of children (toilet-trained vs. in-diaper). Children who had at least 6 months of follow-up and regular office visits were included in the study group, and the results were compared to the literature as well as the subgroups were also evaluated in terms of complications and catheterization period. A total of 128 patients with 40.4 months of the mean age (6-180 months) and 22.7 months of the follow-up (6-49 months) were included in the study. For the group 1 patients (n = 99) in whom the urethral catheter was removed before 24 h, the mean age and follow-up were 33.4 months (6-150 months) and 22.3 months (6-48 months), respectively. The catheters of group 2 patients (n = 29) were removed after 24 h, and their mean age and follow-up were 64.4 months (6-180 months) and 24.2 months (6-49 months), respectively. The group 2 patients were significantly older than those of group 1 (P < 0.05). The complications, such as fistula, meatal stenosis, tube dehiscence and buried penis, were seen in 11.1% of the group 1 and 13.8% of the group 2 (11.7% in overall), showing no statistically significant difference. On the other hand, 44% of the patients (n = 56) were toilet-trained at time of surgery. Although the mean age (79 months vs. 10.4 months) and the catheter removal time (64.3% vs. 87.5% before 24 h) of this group were significantly longer than the patients in diaper (P < 0.05), no significant difference was determined in terms of complication (14.2% vs. 9.7%). TIP repair with short-term catheterization has similar outcomes to the patients who conventionally carry their stent 7-14 days. The meatal position and the toileting status of the patients are not important in the use and length of catheterization.

Child↗
PubMed2006

Management of neonatal hydronephrosis.

Management of neonatal hydronephrosis is a clinical challenge. The natural history of hydronephrosis has shown that most resolve spontaneously; however, there are a significant number that do not. Although hydronephrosis does not always mean obstruction, it becomes the clinician's role to determine when obstruction will eventually lead to renal damage. Work-up of hydronephrosis diagnosed prenatally starts with a postnatal ultrasound. Using the Society of Fetal Urology (SFU) grading of hydronephrosis based on ultrasonography, a management and treatment algorithm can be constructed. Other studies include a voiding cystourethrogram to evaluate for vesicoureteral reflux or in severe cases of bilateral hydronephrosis to evaluate for posterior urethral valves. Diuretic renography is useful in many cases to evaluate the degree of obstruction and determine differential renal function. The goal is to select the patients who would benefit from early surgical intervention. To achieve that goal, aggressive observation is often required.

Algorithms↗
PubMed2006

Hallucinations after hypospadias repair.

The authors report a case of a 4-year-old child who developed hallucinations after hypospadias repair. He was brought to the emergency department the morning after outpatient surgery where the diagnosis of central anticholinergic syndrome was made. We review oxybutynin overdose and the importance of providing clear instruction to parents and caregivers about the administration of medications.

Child, Preschool↗
PubMed2006

Orchiopexy practice patterns in New York State from 1984 to 2002.

PURPOSE: Cryptorchidism is the most common genital anomaly identified at birth, and endocrine disrupters in the environment may be causing an increase in this entity. To determine whether the rate of surgery for undescended testes is increasing, we evaluated all documented orchiopexies performed in New York State during a 19-year period. MATERIALS AND METHODS: We used the New York State Statewide Planning and Research Cooperative System database to identify all orchiopexies performed between 1984 and 2002. Orchiopexies performed for torsion were excluded. RESULTS: A total of 36,484 boys were included in the study, of whom 26,575 were outpatients and 9,909 were inpatients. The overall rate of orchiopexy in our population (number of orchiopexies performed divided by number of live births during the study period) was 1.39%, and remained fairly constant throughout the study. Most orchiopexies were performed on an inpatient basis early in the study (92% in 1984) but by 2002 only 3% of repairs were done in inpatients. Early in the study (1984 to 1988) only 20% of orchiopexies were performed in patients younger than 2 years. However, between 1999 and 2002, 37.8% of orchiopexies were done before age 2. CONCLUSIONS: Orchiopexy is being performed at an earlier age today than 2 decades ago. However, the majority of orchiopexies are not performed until after the recommended patient age of 2 years. The rate of orchiopexy is substantially higher than the accepted rate of 0.8% to 1.1%. Delayed referral to a surgeon, repair of retractile testicles and truly ascending testicles may account for these findings.

Adolescent↗
PubMed2006

Natural history of patients with multicystic dysplastic kidney-what followup is needed?

PURPOSE: Most clinicians recommend followup with annual ultrasound for patients with multicystic dysplastic kidney. The aim of this study was to determine whether followup ultrasound provides any clinical benefit. MATERIALS AND METHODS: We retrospectively reviewed the charts of 73 patients who were diagnosed with multicystic dysplastic kidney between October 1991 and August 2005. Data were analyzed with respect to patient characteristics and followup information. RESULTS: We identified 61 patients (43 boys and 18 girls) with adequate followup. A total of 49 patients (80%) were diagnosed prenatally and 12 (20%) postnatally. Associated urological anomalies were noted in 16 patients (26%). Median followup was 2.6 years (range 6 months to 37.5 years). Ultrasound examinations showed complete involution in 25 patients (41%) and partial regression in 18 (30%). The size of the multicystic dysplastic kidney increased in 1 patient (1.6%) and was unchanged in 17 (28%) without any pathological manifestations. Median age at complete involution was 2.1 years (range 36 days to 13.7 years). Patients with contralateral compensatory hypertrophy had more rapid complete involution. Urinary tract infection developed in 6 patients, of whom 1 was ultimately found to have reflux and 1 had ureteropelvic junction obstruction. CONCLUSIONS: In our patients with unilateral multicystic dysplastic kidney ultrasound provided little clinically important information. Our data and a review of the literature suggest that once the diagnosis is made, no urological followup is needed. The primary care provider should monitor patients with multicystic dysplastic kidney for hypertension, abdominal mass and urinary tract infection.

Adolescent↗
PubMed2006

Effect of maturation and aging on response of rabbit bladder to bilateral in vivo ischemia/reperfusion.

OBJECTIVES: To evaluate the impact of maturation and aging on the effect of bilateral in vivo ischemia/reperfusion on bladder function. METHODS: Male rabbits were separated into three groups by age: immature, mature, and aged rabbits; and each group was subdivided into five subgroups. Each rabbit was subjected to 2 hours of bilateral ischemia. After ischemia, the rabbits in subgroup 1 were killed immediately; the other subgroups were allowed to recover for 1, 7, or 14 days. Separate control (sham-operated) subgroups were not subjected to ischemia. At the end of the experimental period, the bladder was excised, body and base separated, and two strips were prepared from each and mounted in individual baths. The contractile responses to field stimulation and carbachol, adenosine triphosphate, and potassium chloride were determined for the body. The responses to field stimulation alone were determined for the base. RESULTS: The rabbit body and bladder weights of the mature and aged rabbits were significantly greater than that of the young rabbits, but not different from each other. The mature rabbits were significantly more sensitive to ischemia/reperfusion than were the young rabbits. Finally, the aged rabbits were slightly more sensitive to ischemia/reperfusion than the mature rabbits. CONCLUSIONS: The results of our study have shown that the sensitivity of the bladder to ischemia/reperfusion injury increases with age. A very significant increase was found in the sensitivity between young and mature rabbits, with a significantly smaller increase in sensitivity between mature and old rabbits.

Age Factors↗
PubMed2006

Alteration of contractile and regulatory proteins in estrogen-induced hypertrophy of female rabbit bladder.

OBJECTIVES: Estrogen is essential to mediate physiologic functions in female bladders. Deficiency of estrogen has been speculated to be an etiologic factor for bladder dysfunction in postmenopausal women. Our previous studies have demonstrated that estrogen supplementation in female rabbits induces a "functional hypertrophy" of the urinary bladder smooth muscle. The present study investigated the alterations in the contractile and regulatory proteins in this model. METHODS: Twenty New Zealand white female rabbits were separated into five groups of 4 rabbits each. Group 1 served as the control, groups 2 to 6 underwent ovariectomy (Ovx), and group 2 served as the Ovx without estradiol treatment group. Two weeks after Ovx, groups 3 to 5 were given 17-beta estradiol (1 mg/kg/day) by subcutaneous implant for 1, 3, and 7 days, respectively. The expression of the contractile and regulatory proteins, such as myosin light chain kinase, rho-kinase, and caldesmon, was analyzed by Western blotting. RESULTS: The expression of myosin light chain kinase was enhanced by estradiol supplementation. The expression of rho-kinase-alpha was increased significantly (20-fold) after Ovx, which was downregulated after estrogen supplementation. No significant change was seen in rho-kinase-beta after Ovx or estradiol supplementation. The expression of caldesmon isoforms was enhanced by 1-day estradiol supplementation but decreased to lower levels than those of the control group by 3 and 7 days of estrogen treatment. CONCLUSIONS: The results of the present study have provided more understanding about the role of the contractile and regulatory proteins in detrusor muscle, in both dysfunctional atrophy induced by Ovx and functional hypertrophy induced by estrogen supplementation.

Animals↗
PubMed2006

Results of a 2-year multicenter trial of endoscopic treatment of vesicoureteral reflux with synthetic calcium hydroxyapatite.

PURPOSE: With no FDA approved material available for endoscopic treatment of vesicoureteral reflux, in 2001 we began a prospective multicenter trial of synthetic calcium hydroxyapatite as a subureteral bulking agent in children with traditional indications for surgical repair. MATERIALS AND METHODS: A total of 98 patients (155 ureters) with grades II to IV reflux were enrolled at 10 sites in the United States to obtain 86 patients with completed protocol end points at 3 months. Of the 86 patients 74 underwent renal and bladder ultrasonography, blood count and serum chemistry analysis, and VCUG at 1 year. A total of 46 patients (47%) completed 2-year study end points, including VCUG. RESULTS: At 1 and 2 years 24 of the 74 patients (32%) were cured. Ureteral cure rates were 46% and 40% at 1 and 2 years, respectively. With 35 patients treated and 85% compliance with the required 2-year VCUG the primary center achieved 2-year cure rates of 66% of patients and 72% of ureters. CONCLUSIONS: Synthetic calcium hydroxyapatite is a safe, durable and effective material for endoscopic treatment of VUR. Increased experience with the injection of synthetic calcium hydroxyapatite yields improved results.

Adolescent↗
PubMed2006

Resolution of diurnal incontinence and nocturnal enuresis after adenotonsillectomy in children.

PURPOSE: Adenotonsillar hyperplasia causes upper airway obstruction, leading to obstructive sleep apnea. We reviewed the incidence of nocturnal enuresis in a population of children with adenotonsillar hyperplasia. In addition, we investigated the rate of resolution or improvement in enuresis following surgery for relief of adenotonsillar hyperplasia. MATERIALS AND METHODS: We studied 86 consecutive prepubertal children, 46 boys and 40 girls, who underwent adenotonsillectomy. Severity of adenotonsillar obstruction was graded on a scale of 1 to 4. A questionnaire regarding voiding problems, including nocturnal enuresis, voids per day and daytime enuresis episodes, was filled out preoperatively and postoperatively by the patients and their parents. RESULTS: Among the 86 patients who underwent adenotonsillectomy 36 (42%) had nocturnal enuresis. In patients with nocturnal enuresis the number of episodes was significantly less after adenotonsillectomy. Overall, 12 patients (33%) had complete resolution, 11 (31%) had significant improvement and 13 (36%) showed no change. In addition, we noted a significant decrease in daytime enuresis episodes and voids per day. CONCLUSIONS: Children with upper airway obstruction have a high rate of nocturnal enuresis that improves at twice the anticipated rate after treatment of the airway obstruction. In addition, we observed that daytime voiding dysfunction improves in these patients.

Adenoidectomy↗
PubMed2006

Estrogen induces angiogenesis of the female rabbit bladder.

Postmenopausal bladder dysfunction has been speculated to involve decreased circulating estrogen levels. It is our hypothesis that estrogen induces bladder dysfunctions by modulating blood flow to the bladder, i.e. low estrogen reduces blood flow to the bladder, whereas high estrogen increases blood flow. Our previous studies have demonstrated that estrogen administration in female rabbits induces a 'functional hypertrophy' of the urinary bladder smooth muscle represented by increased smooth muscle mass, which corresponds to increased contractile responses to all forms of stimulation. The present study investigates the effect of estrogen on vasculature density and distribution. Twenty-four female New Zealand white rabbits were separated into six groups of four rabbits each. Group 1 served as controls. Groups 2-6 were ovariectomized. Two weeks after ovariectomy (Ovx), groups 3-6 were given 17-beta estradiol (1 mg/kg per day) by s.c. implant for 1, 3, 7, and 14 days respectively. Blood vessel density and distribution were evaluated by immunohistochemistry and quantitative image analyses. Ovx resulted in significant vascular degeneration and decreased density, whereas estradiol administration mediated a significant angiogenic effect characterized by increased vascular density, and distribution of new vasculature within the smooth muscle bundles of the detrusor. Estradiol-induced vasculogenesis corresponds with our previously demonstrated increase in blood flow to the bladder and increased contractility. The most interesting aspect of these studies is the increased vascularization localized within the muscle bundles rather than between the muscle bundles, which may be important in the link between estrogen and increased incidence of cancers.

Animals↗
PubMed2005

Effect of age on rabbit bladder function and structure following partial outlet obstruction.

PURPOSE: We determined whether young and old rabbits respond differently to partial bladder outlet obstruction. MATERIALS AND METHODS: A total of 16 male New Zealand White rabbits were separated into 2 groups of 8 each. Group 1 consisted of young rabbits (age 7 weeks) and group 2 consisted of old rabbits (age 2 years). Four rabbits per group underwent partial outlet obstructions and 4 underwent sham operation. Four weeks following surgery individual bladder strips were used for contractile studies and the remaining tissue was examined histologically. RESULTS: Contractile responses to all forms of stimulation between the young and old sham operated groups were similar. Contractile responses to all forms of stimulation were significantly decreased to the same degree in the 2 obstructed groups. However, the rate of tension generation to field stimulation was decreased to a significantly greater degree in young vs old bladders. Although young and old bladders showed smooth muscle hypertrophy, older rabbits showed significantly greater thickening of the serosa than young rabbits. Young rabbits showed significant inflammation, hemorrhage and expansion of the lamina propria, whereas old rabbits showed none of these characteristics. CONCLUSIONS: Although there were only minor differences in the physiological response of young and old bladders to obstruction, young rabbits showed a significantly greater degree of histological damage. This may have been due to the thinner wall and greater sensitivity to distention.

Aging↗
PubMed2005

Febrile urinary tract infections in infants: renal ultrasound remains necessary.

PURPOSE: Current guidelines from the American Academy of Pediatrics recommend voiding cystourethrography (VCUG) and renal ultrasound for the radiographic evaluation of infants after a febrile urinary tract infection. Some recent studies have suggested that ultrasound is not necessary in the era of prenatal ultrasound. We reviewed our experience to ascertain the influence that ultrasound has on the treatment of these infants. MATERIALS AND METHODS: We reviewed retrospectively the charts of 282 consecutive patients (5 days to 6 months old, 98 males and 184 females) who underwent radiographic evaluation for a febrile urinary tract infection between October 1995 and August 2001. All patients were evaluated at our institution with VCUG and renal ultrasound. RESULTS: Of 203 patients with normal VCUG ultrasound was abnormal in 32 (16%). Subsequent evaluation demonstrated 1 case each of significant ureteropelvic junction obstruction, ectopic ureter in a bilaterally duplicated system, renal duplication, renal duplication with calculus, ectopic ureter, renal cysts, multicystic dysplastic kidney and renal scarring. In addition, there were 3 cases of ureterovesical obstruction. No significant renal pathology was identified in the other cases. Two of these patients underwent operative intervention. Treatment or parental counseling was altered in 7 others, for a total of 9 of the 203 patients (4.4%). CONCLUSIONS: In our population renal ultrasound adds information to the radiographic evaluation of infants after a febrile urinary tract infection. This information alters treatment and parental counseling in a significant number of patients.

Female↗
PubMed2005

Prenatal ultrasound has led to earlier detection and repair of ureteropelvic junction obstruction.

PURPOSE: We hypothesized that the widespread adoption of prenatal ultrasound in the early 1980s has led to earlier and increased numbers of repairs for ureteropelvic junction (UPJ) obstruction. MATERIALS AND METHODS: The New York State Department of Health database was used to identify all patients who underwent pyeloplasty between 1984 and 2002. RESULTS: A total of 7,758 repairs were evaluated (6,725 pyeloplasties and 1,033 endopyelotomies). There was no substantial change in the rate of repair when adjusted for age specific population during the study period. The annual rate of repair in patients younger than 1 year increased from 94 to 156 per 100,000 live births between the periods 1984 to 1988 and 1989 to 2002. This same upward trend was seen in the children 1 to 9 years old. In contrast, there was a substantial decrease in the rate of repairs in patients 10 to 19 years old and in those 20 to 29 years old (from 10 to 9 per 100,000 and from 12 to 8 per 100,000 population, respectively). The male-to-female ratio of newborns in our series was approximately 3:1, which is consistent with previous reports. Among older patients males underwent fewer repairs such that the male-to-female ratio in patients older than 30 years was 1:2. CONCLUSIONS: The overall rate of UPJ repair has not changed during the last 19 years, but there has been a substantial trend toward repair at an earlier age. This finding suggests that prenatal ultrasound has led to earlier diagnosis of UPJ obstruction, allowing earlier repair and obviating later repair. We also report the novel finding of a decreasing rate of pyeloplasty in males with age. This decrease was not observed in females.

Adolescent↗
PubMed2005

Effect of bladder ischaemia/reperfusion on superoxide dismutase activity and contraction.

OBJECTIVES: To correlate the effect of bilateral in-vivo bladder ischaemia/reperfusion on superoxide dismutase activity (SOD) and then to correlate this with contractile responses to various forms of stimulation. MATERIALS AND METHODS: Twenty mature male New Zealand White rabbits were divided into five equal groups: group 1 (controls); group 2, 2 h of in-vivo bilateral bladder ischaemia; and groups 3-5, 2 h of in-vivo ischaemia followed by 1, 7 or 14 days of reperfusion (recovery). At the end of the treatment period, bladder strips were incubated and placed in isolated baths for contractile studies. The contractile responses to field stimulation, carbachol (10 micromol/L), ATP and KCl were determined. The balance of the bladder body was separated into muscle and mucosa sections and analysed for SOD activity. RESULTS: There were few effects on contraction either directly after ischaemia or after 1 day of reperfusion. However, all contractile responses were significantly reduced at 7 and 14 days after ischaemia. SOD activity of the detrusor muscle was reduced significantly immediately after ischaemia and at 7 and 14 days of reperfusion. SOD activity of the mucosa was significantly greater than that of the muscle, and was significantly reduced by both ischaemia and all times of reperfusion. CONCLUSIONS: These studies show clearly that both ischaemia and reperfusion result in significantly lower activity of SOD, and in contractile dysfunctions, and that reperfusion results in greater decreases in both SOD activity and contractile responses than ischaemia alone.

Animals↗
PubMed2005

Apoptosis and proliferation in human undescended testes.

OBJECTIVE: To study apoptosis and proliferation in the testes of children with undescended testes; the degree to which undescended testes contributes to a patient's ultimate fertility is debatable, but undescended testes have fewer germ cells, and some have proposed that apoptosis is an important cause. PATIENTS AND METHODS: Testis biopsies were taken at the time of orchidopexy in a consecutive series of children undergoing surgical repair for undescended testes. Immunohistological techniques were used to detect apoptosis and proliferation, and the numbers of cells undergoing apoptosis or proliferation per 50 seminiferous tubules were recorded. RESULTS: Inguinal testes had less apoptosis than abdominal testes, with a mean (sd) of 0.71 (1.31) vs 1.63 (1.95) apoptotic cells per 50 seminiferous tubules (P < 0.02). Similarly, there was less apoptosis in children aged > 1 years than in children aged < 1 years (0.68 (1.40) vs 1.35 (1.56); P < 0.03). Proliferation was very limited in all cryptorchid testes. In contrast to cryptorchid testes, five autopsy controls had many more apoptotic cells, (10.60 (1.34) per 50 seminiferous tubules), and many more proliferating cells, (8.40 (6.43) per 50 seminiferous tubules). CONCLUSION: In contrast to animal studies, neither apoptosis nor proliferation was common in undescended testes from 6 months of age onward. However, apoptosis was more common in abdominal testes and in children aged < 1 year. It is likely that, if substantial apoptosis occurs in human undescended testes, it occurs before 6 months of age.

Apoptosis↗
PubMed2005

Protective effects of grape suspension on in vivo ischaemia/reperfusion of the rabbit bladder.

OBJECTIVE: To investigate the potential protective effect of a grape suspension in a rabbit model of in vivo bilateral ischaemia/reperfusion (I/R), which is a causal factor in obstructive bladder dysfunction. MATERIALS AND METHODS: Six groups of four New Zealand White rabbits were treated by twice-daily gavage with aqueous grape suspension (groups 1-3) or sugar-water vehicle (groups 4-6) for 3 weeks. Groups 1 and 4 then received bilateral ischaemia for 2 h, and groups 2 and 5 received bilateral ischaemia for 2 h and reperfusion (recovery) for 1 week. Groups 3 and 6 were controls (sham-operated). The effects on cystometry, in vitro contractile responses, and morphology were evaluated. RESULTS: Ischaemia resulted in significant reductions in the contractile responses to all forms of stimulation in vehicle-fed rabbits, whereas there were no reductions in grape-fed rabbits. Contractile responses were significantly reduced in both I/R groups, but significantly more in vehicle-fed than in grape-fed rabbits. Immunohistochemical studies showed less hypoxia in the bladders of grape-fed rabbits than in vehicle-fed rabbits for both ischaemia-only and I/R groups. CONCLUSIONS: Feeding rabbits with grape suspension provided significant protection against the hypoxic effects of bilateral ischaemia and I/R.

Animals↗