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W Bushman

Publications and source records attributed to W Bushman.

At least 19 recordsLinked to original sources
PubMed2005

Growth, morphogenesis, and differentiation during mouse prostate development in situ, in renal grafts, and in vitro.

BACKGROUND: In vitro organ culture and renal grafting of the urogenital sinus (UGS) have both been used as models of prostate development. However, neither has been rigorously examined for its fidelity to replicate the canonical process of prostate differentiation in situ. METHODS: We assessed size, morphology, histology, and the mRNA expression of differentiation marker genes of the E14 male mouse UGS grown for 0-28 days as sub-renal capsule allografts in nude mice or in culture containing androgen and compared these to UGS development in situ. RESULTS: Development of grafted tissues was morphologically and histologically similar to development in situ but differentiation occurred more rapidly. UGS growth in organ culture resulted in bud formation, but did not trigger cellular differentiation. However, the potential for differentiation was maintained and could be rescued by grafting tissues into nude mice. CONCLUSIONS: In vitro organ culture and renal grafting of UGS tissues may be appropriate models for studying prostatic bud formation, but only grafting is an appropriate model for prostatic differentiation.

Animals↗
PubMed2001

Mesenchymal factor bone morphogenetic protein 4 restricts ductal budding and branching morphogenesis in the developing prostate.

The budding of the urogenital sinus epithelium into the surrounding mesenchyme signals the onset of prostate morphogenesis. The epithelial and mesenchymal factors that regulate ductal budding and the ensuing process of ductal growth and branching are not fully known. We provide evidence that bone morphogenetic protein 4 (BMP4) is a mesenchymal factor that regulates ductal morphogenesis. The Bmp4 gene was most highly expressed in the male urogenital sinus from embryonic day 14 through birth, a period marked by formation of main prostatic ducts and initiation of ductal branching. From an initial wide distribution throughout the prostatic anlage of the urogenital sinus, Bmp4 expression became progressively restricted to the mesenchyme immediately surrounding the nascent prostatic ducts and branches. Exogenous BMP4 inhibited epithelial cell proliferation and exhibited a dose-dependent inhibition of ductal budding in urogenital sinus tissues cultured in vitro. Adult Bmp4 haploinsufficient mice exhibited an increased number of duct tips in both the ventral prostate and coagulating gland. Taken together, our data indicate that BMP4 is a urogenital sinus mesenchymal factor that restricts prostate ductal budding and branching morphogenesis.

Animals↗
PubMed2000

Biofeedback, pelvic floor re-education, and bladder training for male chronic pelvic pain syndrome.

OBJECTIVES: Pelvic floor tension myalgia may contribute to the symptoms of male patients with chronic pelvic pain syndrome (CPPS). Therefore, measures that diminish pelvic floor muscle spasm may improve these symptoms. Based on this hypothesis, we enrolled 19 patients with CPPS in a 12-week program of biofeedback-directed pelvic floor re-education and bladder training. METHODS: Pre-treatment and post-treatment symptom assessments included daily voiding logs, American Urological Association (AUA) symptom score, and 10-point visual analog pain and urgency scores. Pressure-flow studies were obtained before treatment in most patients. Instruction in pelvic floor muscle contraction and relaxation was achieved using a noninvasive form of biofeedback at biweekly sessions. Home exercises were combined with a progressive increase in timed-voiding intervals. RESULTS: Mean age of the 19 patients was 36 years (range 18 to 67). Four patients completed less than three treatment sessions, 5 patients completed three to five sessions, and 10 attended all six sessions. Mean follow-up was 5.8 months. Median AUA symptom scores improved from 15.0 to 7.5 (P = 0.001), and median bother scores decreased from 5.0 to 2.0 (P = 0.001). Median pain scores decreased from 5.0 to 1.0 (P = 0.001), and median urgency scores decreased from 5.0 to 2.0 (P = 0.002). Median voiding interval increased from 0.88 hours to 3.0 hours (P = 0.003). Presence of detrusor instability, hypersensitivity to filling, or bladder-sphincter pseudodyssynergia on pretreatment urodynamic studies was not predictive of treatment results. CONCLUSIONS: This preliminary study confirms that a formalized program of neuromuscular re-education of the pelvic floor muscles together with interval bladder training can provide significant and durable improvement in objective measures of pain, urgency, and frequency in patients with CPPS.

Adolescent↗
PubMed1999

Prostate development requires Sonic hedgehog expressed by the urogenital sinus epithelium.

The prostate gland develops from the urogenital sinus by a testosterone-dependent process of ductal morphogenesis. Sonic hedgehog (Shh) is expressed in the urogenital sinus epithelium and the time course of expression coincides with the formation of the main prostatic ducts. Expression is most abundant in the lumen of the urogenital sinus and in the contiguous proximal duct segments. The initial upregulation of Shh expression in the male urogenital sinus depends on the presence of testosterone. The function of Shh was examined in the male urogenital sinus which was transplanted under the renal capsule of an adult male host mouse. Blockade of Shh function by a neutralizing antibody interferes with Shh signaling and abrogates growth and ductal morphogenesis in the transplanted tissue. These observations show that testosterone-dependent Shh expression in the urogenital sinus is necessary for the initiation of prostate development.

Animals↗
PubMed1999

Hoxa-10 deficient male mice exhibit abnormal development of the accessory sex organs.

The role of mammalian Hox genes in regulating segmental patterning of axial structures and the limb is well established. A similar role in development of soft tissue organ systems has recently been suggested by observations linking several 5' members of the HoxA and HoxD clusters to segmentation events and morphogenesis in the gastrointestinal and genitourinary systems. We have specifically examined the role of Hoxa-10 in development of the male accessory sex organs by characterizing expression of Hoxa-10 in the developing male reproductive tract and correlating expression to morphologic abnormalities in knockout mice deficient for Hoxa-10 function. We report that Hoxa-10 expression in the Wolffian duct and urogenital sinus is regionally restricted and temporally regulated. The domain of expression is defined anteriorly by the caudal epididymis and extends posteriorly to the prostatic anlagen of the urogenital sinus. Expression was maximal at E18 and down-regulated postnatally, well before accessory sex organ morphogenesis is completed. Expression in the prostatic anlagen of the urogenital sinus cultured in vitro does not depend upon the presence of testosterone. Loss of Hoxa-10 function is associated with diminished stromal clefting of the seminal vesicles and decreased size and branching of the coagulating gland. The ductal architecture of the coagulating gland was altered in approximately 30% of mutants examined and suggests a partial posterior morphologic transformation of the coagulating gland. We interpret these data to indicate that Hoxa-10 is expressed in a region specific manner during late gestation and into the perinatal period and that Hoxa-10 is required for normal accessory sex organ development.

Animals↗
PubMed1999

Urinary tract infection: a moving target.

Urinary tract infection is an old problem that continues to present new challenges. The purpose of this special edition is to pull together new basic scientific information regarding the pathogenesis of infection and to review the state of the art in the evaluation and treatment of urinary tract infection in some of the more complex or challenging clinical settings. The goal has been more than a summarization of current knowledge; the intent has been to highlight areas of uncertainty, thereby emphasizing the need for further investigation. Herein we briefly mention four clinical settings for urinary tract infection that, in our opinion, present important new or evolving challenges and are particularly fertile areas for further work.

Bacteriuria↗
PubMed1999

Questionnaire based results of the bulbourethral sling procedure.

PURPOSE: The success rate of the bulbourethral sling procedure to treat post-radical prostatectomy incontinence has been reported in a previous chart review analysis. We present further evaluation of the procedure using postoperative mailed questionnaires. MATERIALS AND METHODS: Between October 1994 and October 1997, 66 men underwent the bulbourethral sling procedure at our hospital. Postoperatively all patients with indwelling bolsters were mailed questionnaires to assess continence status, discomfort and voiding patterns. RESULTS: Of the 66 patients 4 required bolster removal for infection (2), erosion (1) or pain (1), and 1 died. These patients were not assessed further. Questionnaire data were obtained from the remaining 61 patients. At a median followup of 9.6 months (mean 11.9, range 3 to 30) 25 patients (41%) reported complete cure of incontinence, 32 (53%) required no pad for protection and 52 (85%) required 2 pads or less. Persistent perineal numbness or discomfort was present in 32 patients (52%). Of 12 patients who received adjuvant radiation therapy only 1 (8%) was cured. CONCLUSIONS: The short-term success rate following the bulbourethral sling procedure is high but persistent perineal discomfort is common. Adjuvant radiation predisposes to treatment failure.

Aged↗
PubMed1999

Urodynamic analysis of the bulbourethral sling procedure.

PURPOSE: The bulbourethral sling procedure is successful in correcting incontinence following radical prostatectomy. However, the mechanism of action of the sling is not intuitively clear. We analyze the results of urodynamic testing on a cohort of men who underwent the bulbourethral sling procedure. MATERIALS AND METHODS: Between October 1994 and October 1997, 66 men underwent the bulbourethral sling procedure at our hospital. All but 1 patient underwent preoperative video urodynamic testing. Intraoperative urethral pressure profilometry and abdominal leak point pressure measurements were performed. Additionally, all patients were invited to undergo followup video urodynamic testing. Results were correlated with current continence status. RESULTS: Preoperatively all patients demonstrated intrinsic sphincter deficiency. Following sling placement postoperative Valsalva leak point pressure values were significantly increased but maximum resting urethral pressures were unchanged. Preoperative and postoperative Abrams-Griffiths nomograms were not consistent with postoperative bladder outlet obstruction. Postoperative voiding pressures were consistently less than corresponding Valsalva leak point pressures. CONCLUSIONS: Patients undergoing video urodynamic testing following the bulbourethral sling procedure demonstrated unobstructed voiding patterns, despite significant increases in Valsalva leak point pressures.

Humans↗
PubMed1999

Hoxa-13 gene mutation results in abnormal seminal vesicle and prostate development.

The role of Hoxa-13 in postnatal morphogenesis of the male accessory sex organs was assessed by correlating the Hoxa-13 expression domain with phenotypic abnormalities in heterozygous Hypodactyly mutants. Hypodactyly is a naturally occurring semi-dominant mutation that results from a 50-base pair deletion in exon one of the Hoxa-13 allele. We demonstrate that Hoxa-13 is broadly expressed in the developing lower genitourinary tract and that the Hypodactyly mutation results in a specific phenotype characterized by decreased size and branching of the dorsolateral and ventral prostate and abnormal seminal vesicle morphology. This phenotype partially overlaps the genitourinary phenotype observed in Hoxd-13 deficient mice and comparison showed similar domains of Hoxa-13 and Hoxd-13 expression in the lower genitourinary tract. The similarity in expression and overlap in phenotype resulting from mutation is consistent with additive function and partial functional redundancy of Hoxa-13 and Hoxd-13 in male accessory sex organ development.

Animals↗
PubMed1997

Male accessory sex organ morphogenesis is altered by loss of function of Hoxd-13.

The role of the Hox gene Hoxd-13 in postnatal morphogenesis of the male accessory sex organs was examined by correlating the distribution and temporal regulation of expression in the accessory sex organs of postnatal mice with morphologic abnormalities of Hoxd-13-deficient transgenic mice. Previous studies of Hoxd-13 expression in the perinatal period have shown a broad domain of expression in the lower genitourinary tract, with expression in both mesenchyme and epithelium; focal expression was also noted in the epithelium of the nascent ducts of the developing prostate. Quantitative RT-PCR studies of Hoxd-13 expression in the 5 day mouse confirm widespread expression in the accessory sex organs developing from both the Wolffian duct and the urogenital sinus. Expression is down-regulated with age, and a detailed time course of expression in the developing prostate shows that the level of Hoxd-13 expression correlates with morphogenetic activity in the development of the prostate ductal system. Transgenic Hoxd-13-deficient mice display multiple abnormalities in the male accessory sex organs. The most severe abnormalities were observed in organs exhibiting ductal branching during postnatal development and included diminished mesenchymal folding in the seminal vesicles, decreased size and diminished ductal branching in the ventral and dorsal prostate, and agenesis of the bulbourethral gland. We conclude that Hoxd-13 expression in the postnatal period correlates with a period of intense morphogenetic activity in accessory sex organ development and that the function of Hoxd-13 is evidenced by morphologic abnormalities in accessory sex organs of the Hoxd-13-deficient mutant.

Animals↗
PubMed1997

Inhibition of prostate ductal morphogenesis by retinoic acid.

PURPOSE: To examine the effect of retinoic acid on prostate ductal morphogenesis. MATERIALS AND METHODS: Newborn male Balb/C mice were injected with 25 mg./kg. all-trans retinoic acid or vehicle alone. Animals were sacrificed at 60 days of age and prostate ductal morphology was quantitatively assessed by microdissection. Total prostate DNA was quantitated by DPA assay. RESULTS: The greatest effect was seen in the ventral prostate. Retinoic acid treated animals showed a 20% decrease in mean number of branch-points (p = 0.0006) with a corresponding 13% decrease in duct tips (p = 0.026). The combined ventral and dorsal prostate showed an effect with a 12% decrease in ductal branchpoints (p = 0.048). There was no effect on animal or organ weight and no effect on DNA content within the prostate. There was no difference in the prostate histology of treated and control animals. CONCLUSION: Retinoic acid administration in the newborn period inhibits mouse prostate ductal morphogenesis. This effect appears independent of an inhibition of overall growth.

Animals↗
PubMed1996

Pax-2: a developmental gene constitutively expressed in the mouse epididymis and ductus deferens.

PURPOSE: To characterize expression of the transcriptional activator, Pax-2, in the mouse lower genitourinary tract. MATERIALS AND METHODS: Expression of Pax-2 was studied by Northern analysis, ribonuclease protection and immunohistochemistry. RESULTS: Immunostaining revealed localized expression in the epithelium of the ductus deferens and epididymis at all time points from birth to adulthood. Expression in these structures in adult mice was confirmed by Northern analysis and ribonuclease protection assays. CONCLUSION: Pax-2 is a transcriptional regulator expressed in the epithelium of the ductus deferens and epididymis and may be a regulator of epithelial genes involved in sperm maturation and support.

Animals↗
PubMed1996

Expression of the homeotic gene Hox-d13 in the developing and adult mouse prostate.

PURPOSE: To examine expression of the homeotic gene Hox-d13 in the developing mouse prostate. MATERIALS AND METHODS: Expression was assayed by Northern analysis, reverse-transcriptase polymerase chain reaction and in situ hybridization. RESULTS: Expression is present in the urogenital sinus in late gestation and is localized postnatally in the urethral epithelium and prostatic ducts. Expression continues throughout development and persists in the adult prostate. CONCLUSION: A restricted domain of Hox-d13 expression in the developing urogenital tract is consistent with the role of the Hox genes in specifying regional identity during development. Expression in the prostate postnatally suggests additional roles in prostate ductal morphogenesis and/or cell differentiation.

Animals↗
PubMed1995

Immunohistochemical staining of ras p21: staining in benign and malignant prostate tissue.

A total of 124 specimens of prostate tissue (25 normal prostate, 41 benign prostatic hyperplasia, 58 adenocarcinoma) was immunostained for ras p21 using a commercially available monoclonal antibody directed against a peptide sequence conserved among all members of the ras gene family. Of normal prostate specimens, 76% showed no staining while the remainder showed only weak epithelial (glandular) staining. No significant stromal staining was noted in any normal prostate specimen. In contrast most benign prostatic hyperplasia specimens showed abundant staining. Epithelial staining was observed in 88% and stromal staining in 73% of specimens. A majority of prostate carcinoma specimens also stained, with 62% and 36% showing epithelial and stromal staining, respectively. No association was noted between staining and either tumor grade or clinical stage. These data argue against any clinical usefulness of immunostaining for ras p21 in the diagnosis or grading of prostate cancer.

Adenocarcinoma↗
PubMed1994

Abnormal flow cytometry profiles in patients with interstitial cystitis.

Flow cytometry was performed on bladder cells from patients with interstitial cystitis and control patients. Cells were processed in standard fashion for flow cytometry with propidium iodide staining and analysis was restricted to samples with sufficient cells for cytokeratin gating and acceptable coefficients of variation. Of 14 interstitial cystitis patients 4 (29%) demonstrated aneuploid deoxyribonucleic acid (DNA) profiles as evidenced by a discrete peak with a DNA index of 1.2 or greater in the cytokeratin positive population. The aneuploid peak accounted for up to 54% of the cytokeratin positive population in these samples. No such aneuploid DNA profiles were evident in specimens obtained from control patients. A significant DNA tetraploid population, as evidenced by a 4C (G2) peak greater than 20%, was observed in 6 of 14 interstitial cystitis patients (43%) and 8 of 11 controls (72%). Manual counting of the per cent of binucleated cytokeratin positive cells in the cytokeratin stained population and nuclear preparations of several samples for flow analysis indicate that apparent DNA tetraploidy in the interstitial cystitis and control patients is due to an abundance of binucleated cells. Aneuploid DNA profiles on barbotage specimens from interstitial cystitis patients may reflect a real karyotypic abnormality or altered chromosome complement (true aneuploidy), abnormal chromatin structure or abnormal cytoplasmic binding of the propidium iodide stain. This finding may signal an underlying abnormality of the epithelial cell population in some patients with the clinical diagnosis of interstitial cystitis.

Adult↗
PubMed1994

The use of urea for dissolution of urinary mucus in urinary tract reconstruction.

Increased urinary mucus is common after urinary tract reconstruction involving the use of bowel segments. This mucus can prove troublesome when it interferes with emptying of the bladder reservoir, particularly in the prepubertal boy, in whom a small catheter must be be used. We report a rapidly effective, nontoxic, inexpensive method of dissolving urinary mucus by periodic instillation of a concentrated urea solution.

Child↗