Biomedical subjects

E T Gonzales

Publications and source records attributed to E T Gonzales.

At least 19 recordsLinked to original sources

PubMed2000

Diagnosis and management of incidental ureterocele during the treatment of clinically localized prostate cancer.

Two instances of simultaneous diagnosis of prostate cancer and ureterocele were recently identified. In one patient an ectopic ureterocele in a duplex system with an obstructed upper pole was unroofed at the time of radical prostatectomy. Surgical excision of the ureterocele wall provided decompression of the obstructed system. In a second patient, bilateral intravesical ureteroceles associated with normal renal units were left untreated. Complications were not associated with the untreated ureteroceles. On rare occasions a ureterocele may be discovered incidentally during the evaluation of patients with prostate cancer. When radical prostatectomy is planned, treatment of the ureteroceles should be determined by the ureterocele's size, anatomic configuration, and location and by the degree of obstruction of the affected renal unit. Surgical excision of the ureterocele at the time of radical prostatectomy may be the best approach for patients requiring treatment.

Adenocarcinoma↗

PubMed2000

Identification of novel genes expressed during metanephric induction through single-cell library screening.

BACKGROUND: Development of the mature kidney is dependent on a series of inductive events between a portion of the epithelial bud at the distal end of the nephric duct and a neighboring domain of committed metanephric mesenchyme. Several genes have been identified to date that are critical in the inductive process. For example, the deletion of Bmp7 from the mouse genome results in dysgenesis or agenesis of the kidney. These findings suggest that Bmp7 controls the expression of genes important for nephrogenesis, but the identity of these genes has remained largely undetermined. METHODS: Single cells were isolated from mouse metanephric mesenchyme during the time of induction (between E11.0 and E11.5) and cDNA libraries constructed from induced and uninduced tissue. Subtractive hybridization was performed to isolate genes that were expressed during E11.5 but not E11.0. RESULTS: Using this approach, we identified eight previously known genes, three of which were known to be involved in metanephric induction, thus validating our approach, and nine novel genes. Eight of these genes were completely novel, whereas one was similar to a member of the yeast Anaphase Promoting Complex. CONCLUSIONS: Through subtractive hybridization of mouse E11.0 and E11.5 metanephric mesenchyme single-cell cDNA libraries, we have identified novel genes that are candidates for involvement in nephrogenesis through their up-regulation during the inductive process.

Amino Acid Sequence↗

PubMed2000

The dorsal inlay graft for hypospadias repair.

PURPOSE: Hypospadias is a common genitourinary anomaly affecting every 1/300 male newborns. The goals of hypospadiac surgery include a straight penis with a urethral meatus at the tip of the glans, a well vascularized neourethra of adequate caliber with a solid, straight urinary stream and achievement of sexual function when mature. Current theory advocates preservation of the urethral plate with chordee correction. Hypospadias repair without an adequate urethral plate to roll into a tube requires longitudinal incision of the plate or a transverse preputial island flap. We describe a technique of 1-stage urethroplasty using an inner preputial based dorsal inlay graft. MATERIALS AND METHODS: After the penis is degloved and chordee corrected incisions are made bilaterally along the urethral plate from the native urethral meatus to the glans tip. The urethral plate is incised longitudinally. A graft harvested from the inner prepuce is defatted and sutured onto the incised urethral plate. The neourethra is rolled into a tube in Thiersch-Duplay fashion. RESULTS: This technique was used in 32 patients. The original urethral meatus was coronal to penoscrotal and chordee release was performed concomitantly. At 21 months of followup no patient had a stricture, fistula or diverticulum at the inlay graft site. CONCLUSIONS: This technique successfully fulfills all traditional hypospadias repair criteria. We believe that the dorsal inlay graft after incision of the urethral plate is a rapid, easy and successful addition to the armamentarium of the "hypospadiologist."

Child↗

PubMed2000

Upper urinary tract manifestations of the VACTERL association.

PURPOSE: In patients suspected to have the vertebral, anal, tracheoesophageal, renal, radial, cardiac and limb abnormalities (VACTERL) association we studied the frequency of upper urinary tract anomalies, prevalence of these features, predictability of upper tract pathology and proper screening evaluation. MATERIALS AND METHODS: From 1991 to 1998 we identified 55 patients with the VACTERL association. Upper urinary tract assessment, including initial renal ultrasound and voiding cystourethrography, and followup data were available for 29 boys and 15 girls. Patients were considered to have the VACTERL association when 3 or more organ systems were involved. RESULTS: Average followup was 5.4 years. Upper urinary tract involvement was noted in 41 of the 44 patients (93.2%) and vesicoureteral reflux in 17 (25 renal units). Of the kidneys 21 were hydronephrotic without reflux or obstruction, 10 were solitary, 3 were multicystic dysplastic, 8 were obstructed and only 17 were normal. A total of 27 patients (61%) underwent at least 1 genitourinary procedure, primarily ureteroneocystotomy. All children were alive at the last followup. CONCLUSIONS: The VACTERL association involves multiple serious anomalies. However, these infants generally have a good outcome. Since the upper urinary system is the most common organ system involved, patients should receive prophylactic antibiotics until an initial urological assessment with renal ultrasound and voiding cystourethrography is performed. It is essential for physicians to know that most children with the VACTERL association have urological involvement that requires treatment and long-term management.

Abnormalities, Multiple↗

PubMed1999

A multicenter outcomes analysis of patients with neonatal reflux presenting with prenatal hydronephrosis.

PURPOSE: Approximately 10 to 30% of prenatal cases of hydronephrosis result in the postnatal diagnosis of vesicoureteral reflux. Using a new generic prenatal-postnatal data sheet developed by the Society for Fetal Urology the characteristics, natural history and outcome of prenatal hydronephrosis confirmed postnatally to be vesicoureteral reflux were documented at 3 centers. MATERIALS AND METHODS: We performed a retrospective multicenter review of Society for Fetal Urology data sheets completed for each patient in whom prenatal hydronephrosis was proved to be postnatal vesicoureteral reflux from 1993 to 1998. RESULTS: In 56 male and 15 female patients with prenatal hydronephrosis a total of 116 refluxing renal units were confirmed postnatally. Of the 116 renal units 112 were hydronephrotic prenatally. During gestation increased hydronephrosis was noted with voiding in 4 cases. Of the 112 hydronephrotic renal units only 26 ureters in 15 patients were seen prenatally. The obstetrician considered the diagnosis of vesicoureteral reflux in only 24% of the cases. Postnatally 116 refluxing renal units were identified. Initial postnatal ultrasound was normal in 25% of the cases. Bilateral reflux was present in 36 male and 9 female patients. In 10 of the 19 uncircumcised patients (53%) urinary tract infection developed despite antibiotic prophylaxis. In 15 of the 74 renal units with grades III to V reflux the condition resolved at an average patient age of 0.9 and 2.1 years in boys and girls, respectively. A total of 27 refluxing renal units were reimplanted. CONCLUSIONS: The majority of prenatal reflux occurs in boys, and it is high grade and bilateral. The data sheets designed by the Society for Fetal Urology are useful data collection instruments. The presentation and natural history of vesicoureteral reflux are different in male and female individuals. In a significant number of renal units high grade reflux resolves spontaneously. Early circumcision may decrease the incidence of breakthrough urinary tract infection in this subpopulation. In addition, the effective management of prenatally detected reflux depends on multispecialty communication.

Female↗

PubMed1999

Bilateral posterior pelvic resection osteotomies in patients with exstrophy of the bladder.

This paper describes a modification of bilateral posterior iliac osteotomies for bladder exstrophy, in which a strip of ilium is resected subperiosteally lateral to the sacroiliac joints, allowing easier anterior closure with less breakdown compared with traditional osteotomies. Thirty-one children underwent repair of bladder exstrophy between 1974 and 1994. Orthopaedic procedures included: closed reduction and cast application in the newborn period (four patients), classic bilateral posterior iliac osteotomies (12 patients), and bilateral posterior resection osteotomies (15 patients). Dehiscence occurred after one closed reduction, five classic osteotomies, and one resection osteotomy. Urinary continence was obtained in four patients who underwent closed reduction, nine patients who underwent classic posterior osteotomies, and nine patients who underwent posterior resection osteotomies.

Bladder Exstrophy↗

PubMed1999

Current management of the infant with myelomeningocele.

Infants with myelomeningocele continue to be a management dilemma for urologists. This article discusses many of the current questions that surround the newborn with myelomeningocele. What radiologic studies should be performed and when? How does the clinician determine if bladder drainage is adequate or requires altering? If a problem is identified what are the surgical options? When should urodynamics be performed? Ultimately how one manages, follows and initiates treatments in the newborn will have a significant effect on the long-term morbidity seen in this population of children.

Female↗

PubMed1999

Analysis of homeobox gene HOXA10 mutations in cryptorchidism.

PURPOSE: Cryptorchidism is the most common congenital abnormality of the genitalia. However, its exact etiology remains to be defined. Homeobox (HOX) containing genes have a key role in the morphogenesis of segmental structures along the primary body axis, including the urogenital mesenchyma. In male mice with a targeted deletion of the HOXA10 gene cryptorchidism manifests in the absence of other major defects. Because to our knowledge this gene has never been examined for alterations in humans, we evaluated whether mutations of HOXA10 are associated with cryptorchidism in humans. MATERIALS AND METHODS: Genomic deoxyribonucleic acid (DNA) was extracted from human blood or tissue samples from 16 noncryptorchid control subjects and 45 cryptorchid boys. To screen for mutations exons 1 and 2 of the HOXA10 gene were amplified individually by polymerase chain reaction using 6 overlapping oligonucleotide primer pairs. Single strand conformational polymorphism (SSCP) analysis of the amplified radiolabeled DNA fragments was performed. Variant band shifts were detected due to abnormal migration of the denatured DNA fragment compared to controls, suggesting an alteration in the DNA sequence. Sequence analysis of these variant bands was then done to define any mutations. RESULTS: SSCP analysis revealed variants in 2 controls. Of the 45 samples from cryptorchid patients 30 had SSCP variants in exon 1. No variants were found in other regions of the gene. Sequence analysis revealed several DNA polymorphisms in exon 1 in controls and boys with cryptorchidism. Other nucleotide changes (point mutations) were noted only in exon 1 in the DNA of 5 cryptorchid patients, of whom 1 had a 24 nucleotide deletion. CONCLUSIONS: Our initial analysis of the HOXA10 gene in humans demonstrates that genetic alterations of this gene may be present in some boys with cryptorchidism. HOXA10 polymorphisms exist in normal control subjects as well as in cryptorchid patients. Further analysis of the function of the mutated protein will elucidate the role of this gene as a potential causative factor of testicular descent.

Child↗

PubMed1998

Androgen receptor gene alterations are not associated with isolated cryptorchidism.

PURPOSE: Multiple theories of testicular descent exist but there is no consensus. Cryptorchidism is a component of the androgen insensitivity syndrome, suggesting that testicular descent may be at least partially under the control of androgenic stimulation. To determine whether isolated cryptorchidism may be caused by androgen insensitivity, we screened a population of boys with isolated cryptorchidism for the presence of androgen receptor gene alterations. MATERIALS AND METHODS: Deoxyribonucleic acid (DNA) was isolated from tissue collected from 21 patients with isolated cryptorchidism during orchiopexy. Patient selection was biased to maximize the likelihood of detection of a genetic etiology of cryptorchidism. The DNA was screened for androgen receptor gene alterations in exons 2 to 8 using single strand conformational polymorphism analysis. RESULTS: No abnormalities in the androgen receptor gene were detected by single strand conformational polymorphism analysis in any patient. CONCLUSIONS: Mutations of the androgen receptor gene in the hormone and DNA binding domains of the protein appear to be an unlikely cause of isolated cryptorchidism.

Child↗

PubMed1998

Long-term adjustment issues in patients with exstrophy.

PURPOSE: We explored the psychological adjustment of children with bladder or cloacal exstrophy. MATERIALS AND METHODS: We assessed 29 subjects with a mean age plus or minus standard deviation of 7.8 +/- 3.97 years using age appropriate standard psychological instruments. Psychological adjustment scores in the exstrophy group were compared to the norms of the various instruments. Subjects were divided into dichotomous groups according to several medical and demographic factors. For each factor the differences between the means of the 2 groups on the outcome variables were calculated using a t test. RESULTS: Children with exstrophy perceived their appearance more positively than the norm. Older children performed more poorly than younger children in adaptive behavior, specifically in skills related to functioning in school. Children who achieved continence after age 4 years were more likely to have problems with acting out behavior. There were no differences in adjustment in boys versus girls, bladder versus cloacal exstrophy, type of continence strategy or gender reassignment versus no reassignment. CONCLUSIONS: Children with exstrophy did not have clinical psychopathology. Differences existed in adaptive and acting out behavior rather than depression or anxiety, suggesting that improved outcomes may be achieved through a focus on normal adaptation rather than on potential psychological distress.

Adaptation, Psychological↗

PubMed1997

Distal hypospadias repair with meatal-based flaps on an outpatient basis.

We report the results of primary repairs that were performed on 52 consecutive patients with distal hypospadias as an outpatient procedure. A modified Mathieu repair with meatal-based vascularized flap was performed under 2.5 optical magnification using Scottring retractors, traction sutures, micro instruments and fine suture material. A total of 3 patients had complications that required reoperation (5.8%). One of these 3 complications was a urethrocutaneous fistula (1.9%). We found that the repair of distal hypospadias was successful with meatal-based flap using contemporary finer approaches and equipment.

Ambulatory Surgical Procedures↗

PubMed1997

Pediatric pyeloplasty: outcome analysis based on patient age and surgical technique.

OBJECTIVES: To analyze our experience with open pyeloplasty, with specific emphasis on procedural outcome on the basis of patient age, surgical technique, complication rate, and complication management. METHODS: All patients from 1974 to 1994 who underwent pyeloplasty at our institution were included in our review. Charts were analyzed for age at presentation, presenting signs and symptoms, type of surgical reconstruction, complications and treatment, and final outcome. RESULTS: From 1974 to 1994, 234 pyeloplasties were performed in 227 patients (108 less than 1 year old, 119 more than 1 year old). The percentage of children less than 1 year old increased throughout: 24% for 1975 to 1980, 37% for 1981 to 1990, and 69% for 1991 to 1994. Presenting signs and symptoms varied according to the age of the child at pyeloplasty. For children less than 1 year old, these were prenatal ultrasound in 86 (79%), urinary tract infection (UTI) in 9 (8%), and abdominal mass in 5 (4.6%). For children more than 1 year old, these were pain in 57 (48%), UTI in 29 (24%), hematuria in 12 (10%), and prenatal ultrasound in 3 (2.5%). Reconstruction was a dismembered pyeloplasty in all cases. The majority of patients in both age groups underwent a nonintubated repair (less than 1 year old, 99 of 114; more than 1 year old, 102 of 120). Postoperative results were evaluated by ultrasound or intravenous urography, with improvement or stable results in 95% of children less than 1 year old and in 96% of children more than 1 year old. Complications included UTI in 18 patients (7.7%), recurrent obstruction in 5 (2.1%), and persistent leak in 4 (1.7%). The complication rate was not related to age. CONCLUSIONS: The nonintubated, dismembered pyeloplasty is an excellent technique for all age groups and has a low complication rate.

Age Factors↗

PubMed1997

Laparoscopic management of persistent Müllerian duct remnants associated with an abdominal testis.

In recent years, laparoscopy has evolved from a purely diagnostic procedure in the management of nonpalpable testis to a definitive therapeutic intervention. Additional genital malformations occur in association with cryptorchidism, but reports of laparoscopic management of such entities do not exist. Herein, we describe the laparoscopic removal of persistent Müllerian duct remnants (uterus and round ligament) in combination with an orchiectomy of an abnormally small abdominal testis. This technique expands the versatility of laparoscopic management of cryptorchidism to include the resection of associated congenital anomalies.

Abdomen↗

PubMed1997

Comparison of onlay and tubularized island flaps of inner preputial skin for the repair of proximal hypospadias.

PURPOSE: Transverse island flaps of inner preputial skin have provided a reliable technique for the repair of proximal hypospadias. The flap may be used to create a neourethra by tubularizing the flap after urethral transection or applying the flap as an onlay patch onto an intact urethral plate. We retrospectively analyzed our experience with these 2 techniques to compare outcomes. MATERIALS AND METHODS: During 11 years 132 patients underwent hypospadias repair by a single surgeon using an onlay (58) or tubularized (74) island flap technique. Surgical results were reviewed retrospectively. RESULTS: At a mean followup of 20.3 months the overall complication rate was 36% for tubularized and 31% for onlay repair, and fistula rates were 14 and 17%, respectively. Despite similar fistula rates tubularized repairs tended to have larger fistulas that required more complex repair (p = 0.0147). In 9 patients who underwent tubularize repair diverticula developed, whereas no diverticula developed after onlay repair (p = 0.0162). The rates of urethral stricture, wound infection, residual chordee and cosmetic complications were not statistically significantly different between repairs. The use of double faced repair in 30 patients provided no difference in outcome in comparison to the overall study cohort. CONCLUSIONS: Hypospadias repair using transverse island flaps offers reliable and durable outcomes. While overall complication rates were not greatly different between tubularized and onlay flap repairs, onlay repair tended to result in fistulas of smaller size and diverticula did not develop.

Follow-Up Studies↗

PubMed1997

A renal size nomogram for the patient with myelomeningocele.

PURPOSE: Renal anatomy and function are usually monitored in the myelomeningocele population using routine ultrasound as the child grows. Clinical questions arise when a renal unit is of marginal size when evaluated with nomograms derived from normal patient populations. Our goal was to construct a renal size nomogram using ultrasound for the myelomeningocele population to help the clinician identify abnormal growth. MATERIALS AND METHODS: We reviewed the charts and radiological files of 96 patients with myelomeningocele followed at our institution. Images of 930 renal units were included to construct the nomogram. Patients were excluded from study due to hydronephrosis or hydroureter, solitary kidney, recurrent symptomatic urinary tract infection, vesicoureteral reflux, reconstructive surgery or known high bladder storage pressure. RESULTS: A renal size nomogram was constructed by plotting patient age against maximal renal length on real-time ultrasound. Expected mean and standard deviations were calculated for each age group. CONCLUSIONS: Previous studies using excretory urography have shown that kidneys in the myelomeningocele population are smaller than in a healthy control population. Ultrasound is now the modality most commonly used to monitor renal anatomy. The creation of a renal nomogram based on ultrasound should help the clinician identify abnormal renal growth more accurately.

Adolescent↗

PubMed1997

Molecular biology and function of the androgen receptor in genital development.

PURPOSE: The rapidly growing field of molecular biology has caused exponential growth in our knowledge of the processes of embryogenesis. Since the cloning of the androgen receptor gene in 1988, investigators have been able to clarify many of the molecular events of male sexual differentiation that are mediated through the androgen receptor. We reviewed the current state of knowledge of the androgen receptor and its role in male genital development. MATERIALS AND METHODS: An intensive literature search was conducted to review reports on the androgen receptor and sexual differentiation since 1988. This review also includes ongoing research from our laboratory on the role of the androgen receptor in human genital development, as well as collaboration with other investigators. RESULTS: We reviewed the basic molecular biology of androgenic action mediated through the androgen receptor. This information has been integrated into the current understanding of human male sexual differentiation to clarify how androgens virilize the undifferentiated embryo. Defects in function of the androgen receptor may be manifested as a spectrum of phenotypes of the androgen insensitivity syndrome, and these phenotypes of male pseudohermaphroditism have been reviewed on a clinical and molecular basis. New molecular techniques have augmented the evaluation and diagnosis of the androgen insensitivity syndrome, and some groups have successfully diagnosed the condition prenatally. CONCLUSIONS: Basic scientific research of androgen receptor function and its role in male sexual development has provided a clearer understanding of the mechanisms responsible for the spectrum of defects secondary to the androgen insensitivity syndrome. This knowledge will enable clinicians to offer more accurate diagnosis and insightful counseling to affected patients and their families.

Disorders of Sex Development↗

PubMed1996

Splenogonadal fusion: report of 2 cases and review of the literature.

PURPOSE: We reviewed the presentation and clinical findings in an unusual scrotal mass seen in children. MATERIALS AND METHODS: This review involves a detailed description of 2 cases of splenogonadal fusion, and a complete survey and assessment of the published literature on this subject. RESULTS: A detailed assessment of 137 cases (135 previously reported, 2 added) of splenogonadal fusion was undertaken. Splenogonadal fusion can be classified as either continuous or discontinuous type. The disorder was rarely recognized before surgery. CONCLUSIONS: In 37% of reported patients orchiectomy was performed because of suspicion that the lesion represented a primary neoplasm. However, orchiectomy is not necessary, since the splenic tissue can be dissected safely off of the tunica albuginea. Therefore, an awareness of the possibility that this anomaly may exist can avoid an unnecessary orchiectomy.

Child↗

PubMed1996

Androgen receptor gene mutations are rarely associated with isolated penile hypospadias.

PURPOSE: Hypospadias has no known single etiology but it has been linked to androgen insensitivity caused by mutations of the androgen receptor gene. The purpose of this study was to search for such mutations in cases of various degrees of isolated hypospadias to determine whether such an association exists and, if so, with any particular anatomical subgroup. MATERIALS AND METHODS: Isolated deoxyribonucleic acid from the penile tissue of 40 patients undergoing reconstructive surgery was screened for mutations of the coding regions of the androgen receptor gene using single strand conformational polymorphism analysis. In cases with abnormal single strand conformational polymorphism findings sequence analysis of the deoxyribonucleic acid was performed to define the mutation. RESULTS: A missense mutation of exon 2 of the androgen receptor gene was noted in 1 patient with isolated distal penile shaft hypospadias. Sequence analysis revealed that the mutation changed amino acid residue 546 from proline to serine. No abnormalities were detected in the other 39 patients. CONCLUSIONS: Isolated distal shaft hypospadias is associated with mutations of the androgen receptor gene but these mutations appear to be a rare cause of hypospadias.

Child↗