Overview of HOMEChem: House Observations of Microbial and Environmental Chemistry.

The House Observations of Microbial and Environmental Chemistry (HOMEChem) study is a collaborative field investigation designed to probe how everyday activities influence the emissions, chemical transformations and removal of trace gases and particles in indoor air. Sequential and layered experiments in a research house included cooking, cleaning, variable occupancy, and window-opening. This paper describes the overall design of HOMEChem and presents preliminary case studies investigating the concentrations of reactive trace gases, aerosol particles, and surface films. Cooking was a large source of VOCs, CO2, NOx, and particles. By number, cooking particles were predominantly in the ultrafine mode. Organic aerosol dominated the submicron mass, and, while variable between meals and throughout the cooking process, was dominated by components of hydrocarbon character and low oxygen content, similar to cooking oil. Air exchange in the house ensured that cooking particles were present for only short periods. During unoccupied background intervals, particle concentrations were lower indoors than outdoors. The cooling coils of the house ventilation system induced cyclic changes in water soluble gases. Even during unoccupied periods, concentrations of many organic trace gases were higher indoors than outdoors, consistent with housing materials being potential sources of these compounds to the outdoor environment. Organic material accumulated on indoor surfaces, and exhibited chemical signatures similar to indoor organic aerosol.

A survey on the current status of laparoscopic training in paediatric surgery in South Africa.

OBJECTIVES: To document the current status of laparoscopic training of paediatric surgical registrars in South Africa. METHODS: An anonymous questionnaire was distributed. Participants were asked to document their involvement in a number of index laparoscopic procedures during the preceding year, as well as additional non-operative training they received and their satisfaction with their training thus far. RESULTS: All registrars (N=16) completed the questionnaire. Registrars were from the Universities of KwaZulu-Natal, Cape Town, Stellenbosch, Pretoria and the Witwatersrand, and Walter Sisulu University. The ratio of consultants proficient in paediatric laparoscopy to registrars was between 0.6 and 1. Junior registrars were more likely to assist with, and senior registrars more likely to perform, procedures. Registrar satisfaction varied greatly across institutions, with 44% of registrars satisfied with their training. CONCLUSIONS: The consultant-to-registrar ratio is favourable, and high patient load provides opportunity for laparoscopic education. However, there are a number of obstacles to adequate training. These include the feasibility of after-hours laparoscopic surgery and the availability and use of training aids. The introduction of a structured training programme across all institutions will improve laparoscopic proficiency and satisfaction among paediatric surgical registrars in South Africa.

Sex pheromone of the citrus flower moth Prays nephelomima: pheromone identification, field trapping trials, and phenology.

Analysis of sex pheromone gland extract of the citrus flower moth, Prays nephelomima (Lepidoptera: Yponomeutidae) by coupled gas chromatography-electroantennogram detection, revealed one electrophysiologically active compound. Structural analysis using gas chromatography, gas chromatography-mass spectrometry, and dimethyldisulfide derivatization identified this as the monounsaturated aldehyde (Z)-7-tetradecenal. Field trials in commercial citrus orchards on the North Island of New Zealand showed that (Z)-7-tetradecenal was highly attractive to male P. nephelomima. Phenology data, collected over 19 months in three commercial orchards, from traps baited with the sex pheromone at a lure loading of 300 microg on a red rubber septum, indicated that male moths may be present throughout the year, with numbers peaking in late summer and autumn.

Enumerative and binomial sampling plans for armored scale (Homoptera: Diaspididae) on kiwifruit leaves.

The spatial dispersion of armored scale insects; greedy scale, Hemiberlesia rapax (Comstock); and latania scale, Hemiberlesia lataniae (Signoret), was investigated on kiwifruit, Actinidia deliciosa (A. Chevalier) C. F. Liang et A. R. Ferguson, leaves in New Zealand. A universal description for dispersion was determined using Taylor's power law, which encompassed a wide range of different orchards, blocks, block sizes, sampling times, scale control practices, regions and seasons. Scale density significantly altered dispersion, especially at the high densities found on unsprayed kiwifruit. Most commercially managed kiwifruit blocks had low densities of <0.5 scale per leaf and had a slightly aggregated scale dispersion. Wilson and Room's binomial model, which incorporates a clumping pattern as a function of density, gave a significant relationship between the proportion of infested leaves and scale density. The optimal leaf sample sizes were estimated for predetermined levels of sampling reliability. Where population estimates require a high degree of precision and enumerative sampling methods are used, 2,500 leaves should be sampled when scale densities are near the current spray threshold of 4% infested leaves and 500 leaves at 20% infested leaves. For management-decision sampling, where a lower level of precision was acceptable, enumerative sampling would require that 400 leaves be sampled at 4%; or 85 leaves at 20% infested leaves. With binomial sampling to achieve an equivalent level of precision an increased sample size of 6-11% is required.

Bowel dysfunction in spina bifida--an American experience with the ACE procedure.

Fecal incontinence remains a detriment to improved quality of life in many patients with spina bifida. Previous methods of conservative management frequently prove to be inadequate, causing many patients to withdraw from the social mainstream. Recent descriptions of procedures to provide access to the proximal colon for antegrade colonic enemas (ACE procedure) have provided a new approach to managing fecal incontinence. We report here our experience with these procedures in 43 patients with spina bifida. The background, techniques and outcomes of these procedures are discussed and a plea is made to consider this approach in all patients who are hampered in their social or vocational progress because of neurogenic anorectal dysfunction.

Crossed ectopia of ovotestis in a case of true hermaphroditism.

True hermaphroditism is a rare form of intersex disorder. The authors report a case of true hermaphroditism with crossed ectopia of an ovotestis from the left to the right scrotum. The karyotype of the patient was 46,XX, without mosaicism. The majority of the ovotestis was comprised of testicular tissue. In other cases of human true hermaphroditism, descent of a pure ovary has not been noted to occur, despite the presence of the contralateral testis. Additionally, in congenital adrenal hyperplasia occurring in genotypic female subjects, pure ovaries do not descend into the scrotum despite the high level of androgens. Taken together, we believe that the demonstrated descent of mostly testicular ovotestes supports the idea that the testis produces a substance other than androgen that is important in guiding its descent.

Treatment of pediatric urolithiasis between 1984 and 1994.

PURPOSE: We report our experience with the management of pediatric urolithiasis during a 10-year period. Our aim was to assess the impact of new technology in the treatment of pediatric urolithiasis. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients up to age 18 years in whom urolithiasis was treated from 1984 to 1994. In 37 cases 24-hour urine collections were available for metabolic evaluation. RESULTS: A total of 100 pediatric patients was treated for urolithiasis. Mean followup was 36 months. A total of 79 patients underwent 115 procedures for symptomatic urolithiasis and 21 were treated nonoperatively. In 42 patients structural anomalies of the urinary tract required additional management. Metabolic abnormalities in 48 patients included hypercalciuria in 19, defined as greater than 4 mg./kg./24 hours calcium by 24-hour urine collection. Only 24 of the 100 patients had no identifiable predisposing factors. Procedures included shock wave lithotripsy in 42 cases, basket extraction with or without ureteroscopy in 20, percutaneous nephrostolithotomy in 11 and litholapaxy in 12. Open surgery included cystolithotomy in 10 cases and other forms of open lithotomy in 15. Thus, open surgical removal was necessary in 1 of 5 cases. CONCLUSIONS: Compared to the traditional mode of stone treatment, fewer patients required open surgery. Our results indicate that a comprehensive approach to the care of pediatric patients with urolithiasis requires attention to metabolic and structural abnormalities.

Modified ASOPA procedure (Hodgson XX) achieves the goals of hypospadias repair.

Several vascularized island flap procedures have been described for the repair of severe hypospadias with chordee. The modified ASOPA (Hodgson XX) procedure, a variant of transverse island flap, employs an inner preputial skin tube for the neourethra while providing simultaneous skin coverage. Since 1988, more than 240 hypospadias repairs have been performed at the authors' institution, including 15 modified ASOPA procedures. All of the patients had proximal hypospadias with chordee. The follow-up of 12 of these patients showed a straight penis, free of chordee, with the meatus at the tip in 11 (92%). One patient had glanular separation and retraction of the meatus to a coronal position. No patient had a urethrocutaneous fistula or urethral diverticulum. Proximal anastomotic strictures were identified in three (25%) patients, which resolved with dilation in two and with internal urethrotomy in the other. The final cosmetic appearance was excellent for 11 patients. Based on these results, the authors conclude that the modified ASOPA procedure reliably achieves the goals of hypospadias repair: release of chordee, urethroplasty, scrotoplasty, and redistribution of skin coverage in one operation, with minimal morbidity.

Common sheath reimplantation yields excellent results in the treatment of vesicoureteral reflux in duplicated collecting systems.

PURPOSE: We evaluated our 10-year experience with the surgical treatment of vesicoureteral reflux in uncomplicated duplicated collecting systems. MATERIALS AND METHODS: Between 1984 and 1994, 54 refluxing renal units (8 bilateral) in 37 female and 9 male patients required surgery. Patient age ranged from 7 months to 17 years (average 4.9 at surgery). Postoperative followup (average 14.2 months) included voiding cystourethrography and renal sonography or excretory urography. RESULTS: Common sheath ureteral reimplantation via an intravesical approach was performed in 48 of the 54 refluxing renal units. Of the remaining 6 renal units detrussorrhaphy was performed in 4, and ureteroureterostomy combined with ureteral reimplantation and partial lower pole nephrectomy were done in 1 each. Two treated renal units had persistent postoperative vesicoureteral reflux, which resolved after subureteral polytetrafluoroethylene (Teflon) injection. No renal had postoperative hydronephrosis. Contralateral reflux was identified in 1 patient who underwent unilateral reimplantation. Our overall success rate was 96% for the surgical correction of vesicoureteral reflux in uncomplicated duplicated collecting systems. Common sheath reimplantation had a 98% success rate. CONCLUSIONS: Although a duplicated collecting system increases the risk for surgical treatment, the presence of a duplication anomaly does not adversely affect surgical outcome. Modifications of procedures commonly performed in the surgical treatment of single system reflux to accommodate common sheath reimplantation have excellent surgical results with minimal morbidity.

The Malone antegrade colonic enema enhances the quality of life in children undergoing urological incontinence procedures.

PURPOSE: Functional alterations of the gastrointestinal and genitourinary tracts, and physical limitations in children with spina bifida, imperforate anus and spinal cord injury challenge the ability to have independent fecal and urinary continence. Urologists have successfully helped these patients achieve urinary continence. We report our experience with the antegrade colonic enema procedure, which allows select individuals to achieve continence of stool, enhancing quality of life. MATERIALS AND METHODS: Since December 1992, 18 antegrade colonic enema procedures were performed in 12 female and 6 male patients 5 to 31 years old of whom 14 had spina bifida, 2 had imperforate anus and 2 had spinal cord injury. Simultaneous urological continence procedures were performed in 8 patients, including appendicovesicostomy in 4, augmentation cystoplasty in 2 and augmentation cystoplasty plus an ileal Mitrofanoff procedure in 2. Four patients previously underwent urological reconstruction. RESULTS: In 24 months of followup (average 6.6) all patients with a functioning stoma remained continent of stool and 17 were continent of urine. Complications related to the antegrade colonic enema procedure occurred in 4 children (22%) of whom 3 required further surgery. Three patients (17%) had minor stomal stenosis. CONCLUSIONS: The antegrade colonic enema procedure is easily performed and it should be considered for any child with significant physical limitations and/or refractory fecal incontinence before urological continence promoting procedures are done.

Correction of retractile concealed penis.

Several different mechanisms may account for the concealed appearance of the penis. A particular type of concealed penis is the retractile penis, due to dysgenetic fibrous bands tethering the penis to the prepubic subcutaneous tissue. The retractile nature of the concealment can be confirmed by flexion of the hips. A simple technique for surgical correction of the retractile penis is described. While there are many different methods to correct a concealed penis, proper selection of the technique based on understanding of the pathophysiology is critical to a successful outcome.

Vaginoplasty: combination therapy using labia minora flaps and lucite dilators--preliminary report.

The treatment of vaginal agenesis is varied. The combination of creating a vaginal cavity with local skin flaps, then progressively dilating to a functional size has been successful in the past. We describe a technique using tubularized labia minora vascularized flaps to create a deep vaginal pouch that is widened and elongated with lucite dilators. The new vagina has an epithelial lining of nonhair-bearing skin. Three teenage girls, 2 with the Mayer-Rokitansky syndrome and 1 with mixed gonadal dysgenesis, underwent this procedure without any postoperative complications. Since neither abdominal surgery nor skin grafting was required there were no extra scars, excessive neovaginal secretions or need for long-term splinting during the 1-year followup period. The patients have almost normal-appearing genitalia postoperatively and neovaginas averaging 2 cm. wide and 6.3 cm. deep before dilation. We recommend this procedure as first line treatment for teenage girls with vaginal agenesis.

Protection of the solitary testis.

In 15 negative explorations for unilateral cryptorchidism, inspection of the contralateral scrotum revealed a "bell-clapper" deformity in 13 patients. Since the descent of the testis is influenced by the gubernaculum and gubernacular abnormalities are usually bilateral, the data suggest that an inadequate gubernaculum is associated with most instances of antenatal and postnatal torsion. Unilateral absence of the testis is a form of this syndrome; congenital monorchidism is probably due to antenatal torsion rather than hypoplasia or agenesis. When monorchidism is confirmed at operation, exploration and suture fixation of the contralateral testis at the same procedure is recommended to protect the solitary testis from future torsion.

Fibroblastic tumor of the urinary bladder after cyclophosphamide therapy.

An unusual fibroblastic tumor occurred in a teenage boy following treatment with cyclophosphamide for Hodgkin's disease. To our knowledge, only one other similar case has been reported. The cellular and structural composition of the tumor resembles that of cyclophosphamide-induced cystitis and therefore suggests a relationship between the two lesions.

Mechanical genital maldevelopment presenting as pseudovaginal perineoscrotal hypospadias.

Pseudovaginal perineoscrotal hypospadias is the descriptive terminology of a phenotypic genital abnormality that may develop from multiple etiologic factors, such as defective virilization-masculinization owing to deficient androgenic synthesis, defective androgenic action or mechanical embryologic failure. The case presented herein typifies a mechanical abnormality that results in perineal hypospadias with the appearance of a vaginal introitus but with rectal mucosa incorporated in the urethral opening.

Urologic complications of neonatal umbilical arterial catheterization.

Two cases are presented illustrating the emergent and potentially lethal complications of neonatal umbilical artery catheterization that may confront the pediatric urologist. Immediate aortography via the umbilical artery catheter usually will be diagnostic. Prompt surgical intervention is advocated if uncontrollable renovascular hypertension or a false aneurysm is found.

Management of the unsuspected ectopic ureterocele.

Five cases of ectopic ureteroceles associated with non-functioning upper pole segments are presented. Diagnosis was not made until the time of operation for correction of vesicoureteral reflux or decompression of the upper tracts through a flank approach. Options in the management of this problem are discussed.

Microradiographic demonstration of pyelolymphatic backflow in the porcine kidney.

Pyelolymphatic backflow occurs when intrapelvic pressure rises acutely. Although peripelvic and hilar lymphatics have occasionally been demonstrated during intravenous urography and retrograde pyelography, the patterns of intrarenal microlymphatic filling have not previously been studied radiographically in multipapillary kidneys. Microradiography was performed after retrograde ureteral injections of barium sulfate suspension in recently excised pig kidneys. Contrast filled the ducts of Bellini and extended in a retrograde fashion as far as the distal convoluted tubules. Intrarenal cortical and corticomedullary microlymphatics, as well as veins, filled following forniceal rupture and interstitial extravasation. These anatomic studies suggest that the renal lymphatics may function as an alternate pathway of drainage of an acutely obstructed kidney.