Temporal Notch signaling regulates mucociliary cell fates through Hes-mediated competitive de-repression

Tissue functions are determined by the types and ratios of cells present, but little is known about self-organizing principles establishing correct cell type compositions. Mucociliary airway clearance relies on the correct balance between secretory and ciliated cells, which is regulated by Notch signaling across mucociliary systems. Using the airway-like Xenopus epidermis, we investigate how cell fates depend on signaling, how signaling levels are controlled, and how Hes transcription factors regulate cell fates. We show that four mucociliary cell types each require different Notch levels and that their specification is initiated sequentially by a temporal Notch gradient. We describe a novel role for Foxi1 in the generation of Delta-expressing multipotent progenitors through Hes7.1. Hes7.1 is a weak repressor of mucociliary genes and overcomes maternal repression by the strong repressor Hes2 to initiate mucociliary development. Increasing Notch signaling then inhibits Hes7.1 and activates first Hes4, then Hes5.10, which selectively repress cell fates. We have uncovered a self-organizing mechanism of mucociliary cell type composition by competitive de-repression of cell fates by a set of differentially acting repressors. Furthermore, we present an in silico model of this process with predictive abilities.

Notch signaling induces either apoptosis or cell fate change in multiciliated cells during mucociliary tissue remodeling

Multiciliated cells (MCCs) are extremely highly differentiated, presenting >100 cilia and basal bodies. Therefore, MCC fate is thought to be terminal and irreversible. We analyzed how MCCs are removed from the airway-like mucociliary Xenopus epidermis during developmental tissue remodeling. We found that a subset of MCCs undergoes lateral line-induced apoptosis, but that the majority coordinately trans-differentiate into goblet secretory cells. Both processes are dependent on Notch signaling, while the cellular response to Notch is modulated by Jak/STAT, thyroid hormone, and mTOR signaling. At the cellular level, trans-differentiation is executed through the loss of ciliary gene expression, including foxj1 and pcm1, altered proteostasis, cilia retraction, basal body elimination, as well as the initiation of mucus production and secretion. Our work describes two modes for MCC loss during vertebrate development, the signaling regulation of these processes, and demonstrates that even cells with extreme differentiation features can undergo direct fate conversion.

ΔN-Tp63 Mediates Wnt/β-Catenin-Induced Inhibition of Differentiation in Basal Stem Cells of Mucociliary Epithelia

Mucociliary epithelia provide a first line of defense against pathogens. Impaired regeneration and remodeling of mucociliary epithelia are associated with dysregulated Wnt/β-catenin signaling in chronic airway diseases, but underlying mechanisms remain elusive, and studies yield seemingly contradicting results. Employing the Xenopus mucociliary epidermis, the mouse airway, and human airway Basal cells, we characterize the evolutionarily conserved roles of Wnt/β-catenin signaling in vertebrates. In multiciliated cells, Wnt is required for cilia formation during differentiation. In Basal cells, Wnt prevents specification of epithelial cell types by activating ΔN-TP63, a master transcription factor, which is necessary and sufficient to mediate the Wnt-induced inhibition of specification and is required to retain Basal cells during development. Chronic Wnt activation leads to remodeling and Basal cell hyperplasia, which are reversible in vivo and in vitro, suggesting Wnt inhibition as a treatment option in chronic lung diseases. Our work provides important insights into mucociliary signaling, development, and disease.

Impaired (re-)generation of lung epithelia is associated with Wnt signaling changes in animals and human lung disease patients. Haas et al. demonstrate that ΔN-TP63 is a Wnt-regulated master transcription factor inhibiting (re-) generation of new epithelial cells from stem cells. These findings are equally important for understanding animal development and disease mechanisms.

Na+/H+ Exchangers Are Required for the Development and Function of Vertebrate Mucociliary Epithelia

Na+/H+ exchangers (NHEs) represent a highly conserved family of ion transporters that regulate pH homeostasis. NHEs as well as other proton transporters were previously linked to the regulation of the Wnt signaling pathway, cell polarity signaling, and mucociliary function. Furthermore, mutations in the gene SLC9A3 (encoding NHE3) were detected as additional risk factors for airway infections in cystic fibrosis patients. Here, we used the Xenopus embryonic mucociliary epidermis as well as human airway epithelial cells (HAECs) as models to investigate the functional roles of NHEs in mucociliary development and regeneration. In Xenopus embryos, NHEs 1-3 were expressed during epidermal development, and loss of NHE function impaired mucociliary clearance in tadpoles. Clearance defects were caused by reduced cilia formation, disrupted alignment of basal bodies in multiciliated cells (MCCs), and dysregulated mucociliary gene expression. These data also suggested that NHEs may contribute to the activation of Wnt signaling in mucociliary epithelia. In HAECs, pharmacological inhibition of NHE function also caused defective ciliation and regeneration in airway MCCs. Collectively, our data revealed a requirement for NHEs in vertebrate mucociliary epithelia and linked NHE activity to cilia formation and function in differentiating MCCs. Our results provide an entry point for the understanding of the contribution of NHEs to signaling, development, and pathogenesis in the human respiratory tract.

Interchangeability and Diagnostic Accuracy of Two Assays for Total and Free Prostate-Specific Antigen: Two not Always Related Items

The variation between different PSA assays seems to influence the interpretation of individual PSA values and the clinical decisions about prostate cancer. One reason for this variability could be the different reactivity of antibodies for the various molecular forms of serum PSA; as a result, samples containing the same amount of tPSA but different proportions of fPSA can produce very different values. In this study, serum samples were collected prospectively from 152 consecutive patients referred to 2 institutions (Regional Hospital, Venice, 90 subjects; San Bortolo Hospital, Vicenza, 62 subjects) for PSA elevation and/or symptoms. Serum samples were assessed according to the manufacturers’ instructions on the following 2 analyzers: the Immulite 2000 assay (Diagnostic Products Corporation, Los Angeles, USA), which measures tPSA and fPSA, and the ADVIA Centaur (Bayer Diagnostics, Tarrytown, USA), which assays tPSA and cPSA. cPSA values were transformed into fPSA by the equation fPSA=tPSA-cPSA. When taking Immulite tPSA and f/tPSA values as 100%, ADVIA Centaur values were 92.6% and 122%, respectively, which means that 20% of patients would be classified differently according to the traditional biopsy cutoff. In conclusion, there are considerable differences between the 2 methods, which could affect clinical decisions.

Acute thrombosis of the renal artery secondary to closed abdominal trauma: our experience and literature revision

Aim

Thrombosis secondary to renal closed abdominal trauma is a rare event, most of the time it is clinically silent. We report here our experience.

Materials and Methods.

This is the case of a boy came to our observation after a road trauma with motorbike fall-out. The boy arrived in ED for head injury. The patient, stable for haemodynamics, had lacerated and contused injuries at pelvis and right buttock level. He underwent chest x-rays, brain CT and neurosurgery examination: all resulted negative. There was no macrohematuria, nor lumbar pain. Objectively abdomen was treatable. The patient was referred to temporary observation for 12 hours when he was asked to undergo abdomen ultrasound, which showed no documented lesions except for fluid collection at the pelvic level. To rule out all doubts, the patient had an abdominal CT scan, which showed a silent left kidney with suspected thrombosis at left renal level. The patient was sent to our attention after 15 hours: we decided to perform immediately selective arteriography with thrombus lysis. The arteriography documented a massive thrombosis. The thrombus lysis was impossible to be performed. To maintain the perfect functionality of the contralateral kidney we decided not to proceed further, but to perform only left nephrectomy. During surgery mesocolon laceration occurred, so the patient underwent also colic resection.

Discussion.

Thrombosis secondary to a closed renal abdominal trauma is an uncommon event, with little clinical expression. It is the consequence of an injury. Deceleration produces arterial dissection, which alters the blood flow to the kidney, which is then twisted and complicated with renal thrombosis. Quite common is the association with diaphragmatic rupture or urethral detachment. The alterations of renal parenchyma in the early hours are detectable only through CT scan, which represents the method of election, and which can highlight a functionally silent kidney.

Conclusions.

Renal thrombosis requires that diagnosis is done within the first 12 hours; a rapid revascularization should be promptly attempted.

[Acute thrombosis of the renal artery secondary to closed abdominal trauma: our experience and literature revision]

Thrombosis secondary to renal closed abdominal trauma is a rare event, most of the time it is clinically silent. We report here our experience. MATERIALS AND METHODS. This is the case of a boy came to our observation after a road trauma with motorbike fall-out. The boy arrived in ED for head injury. The patient, stable for haemodynamics, had lacerated and contused injuries at pelvis and right buttock level. He underwent chest x-rays, brain CT and neurosurgery examination: all resulted negative. There was no macrohematuria, nor lumbar pain. Objectively abdomen was treatable. The patient was referred to temporary observation for 12 hours when he was asked to undergo abdomen ultrasound, which showed no documented lesions except for fluid collection at the pelvic level. To rule out all doubts, the patient had an abdominal CT scan, which showed a silent left kidney with suspected thrombosis at left renal level. The patient was sent to our attention after 15 hours: we decided to perform immediately selective arteriography with thrombus lysis. The arteriography documented a massive thrombosis. The thrombus lysis was impossible to be performed. To maintain the perfect functionality of the contralateral kidney we decided not to proceed further, but to perform only left nephrectomy. During surgery mesocolon laceration occurred, so the patient underwent also colic resection. DISCUSSION. Thrombosis secondary to a closed renal abdominal trauma is an uncommon event, with little clinical expression. It is the consequence of an injury. Deceleration produces arterial dissection, which alters the blood flow to the kidney, which is then twisted and complicated with renal thrombosis. Quite common is the association with diaphragmatic rupture or urethral detachment. The alterations of renal parenchyma in the early hours are detectable only through CT scan, which represents the method of election, and which can highlight a functionally silent kidney. CONCLUSIONS. Renal thrombosis requires that diagnosis is done within the first 12 hours; a rapid revascularization should be promptly attempted.

Plasma bubble formation induced by holmium laser: an in vitro study

OBJECTIVES

To use the elementary physical measurements of temperature and size to prove that the thermal effects produced by the holmium laser's pulses are due to the formation of a plasma bubble. The physical phenomenon related to high temperatures generated during procedures with the holmium laser (holmium:yttrium-aluminum-garnet) was the object of our interest.

METHODS

Using a double micrometric slide attached to a 550-microm optic fiber and two thermocouples submerged in water, a series of pulses of 0.8 J at 10 to 30 Hz was delivered from a holmium:yttrium-aluminum-garnet laser, and we recorded temperatures on both frontal and lateral planes. Subsequently, samples of prostatic tissue and small stones were treated with 1.5 J at 20 Hz on both frontal and lateral planes.

RESULTS

Treatment with 1.5 J at 30 Hz (frontal plane) and with 1.5 J at 20 Hz (lateral plane) produced the ablation of the structure of the thermocouple at 2 mm and 1 mm, respectively, indicating plasma formation. The dimensions of the bubble after the delivery of 1.5 J at 20 Hz was 2 x 1.5 mm. Coagulation of the prostatic tissue took place at 1 mm from the plasma bubble, on both frontal and lateral planes.

CONCLUSIONS

The plasma bubble that forms at the tip of the fiber connected to the holmium:yttrium-aluminum-garnet laser makes it possible to work on stones and soft tissues. The coagulation of the prostatic tissue is caused by the hot water-vapor bubble that forms on the edge of the plasma bubble. During lithotripsy, guidewires and baskets within the expansion area of the plasma bubble risk damage.

Mini-Invasive Management of a Rare Complication of Percutaneous Stone Treatment: Entrapped Nephrostomy Tube

A case of entrapped nephrostomy tube in a 61-year-old woman who underwent percutaneous nephrolithotomy and subsequent multiple ESWL for a left staghorn stone is presented. A nephrostomy track was created alongside the Malecot catheter and the overgrown tissue which was bridging the wings of the tube was incised with a Sachse urethrotome. To prevent this complication the wings of the Malecot should freely expand in the renal collecting system and the catheter should stay in situ for no more than 3 weeks.

High-energy microwave thermotherapy in the treatment of benign prostatic hyperplasia

INTRODUCTION

Transurethral microwave thermotherapy is an anesthesia-free, outpatient method of treating lower urinary tract symptoms due to benign prostatic hyperplasia (BPH). Our results with the use of this technique in 25 patients are reported.

MATERIALS AND METHODS

Twenty-five patients with BPH, 8 of whom with complete urinary retention, were treated with high-energy transurethral microwave thermotherapy (HE-TUMT) (Prostatron system). Preoperative investigations included digital rectal examination, urinary free flow rate, PSA, urinalysis, urine culture, transrectal ultrasonography, urodynamic evaluation, International Prostatic Symptom Score (IPSS) and quality of life (QoL). Main selection criteria included: large prostate, high surgical risk, reluctance to undergo surgery. All patients were obstructed according to the Abrams-Griffith's nomogram. For the statistical analysis a repeated-measures, one-way ANOVA was performed on previously non-catheterized patients.

RESULTS

Six of the 8 patients with catheter before treatment were able to urinate spontaneously with no significant post-voiding residual urine. In the 17 remaining patients, IPSS decreased from a mean of 18.5 at baseline to 7.30 and QoL from a mean of 3.9 to 1.2. Mean maximum flow rates during uroflowmetry increased from 8.5 to 16.9 ml/s. P(det) Q(max) decreased from a mean of 83.0 cm H(2)O at baseline to 50.7 cm H(2)O and Q(max) increased from a mean of 6.8 ml/s at baseline to 15.1 ml/s during the pressure-flow study. After TUMT, 13 patients were unobstructed and 4 equivocal according to the Abrams-Griffith's nomogram.

CONCLUSION

Our study performed in a selected population of patients with BPH documents the efficiency and safety of HE-TUMT. This technique appears to be a valid therapeutic option, particularly in patients with high surgical risk.

Experience with an elective vacuum assisted cardiopulmonary bypass in the surgical treatment of renal neoplasms extending into the right atrium

PURPOSE

We evaluate the results of an elective cardiopulmonary bypass conceived to minimize the surgical risk related to its use with temporary circulatory arrest and deep hypothermia in the treatment of patients with renal tumor extending into the right atrium.

MATERIALS AND METHODS

From July 1996 to December 2000, 19 patients with renal neoplasm and venous involvement were admitted to our department. Three patients 4, 57 and 58 years old with a right (2) and left (1) renal tumor extending into the right atrium underwent radical nephrectomy and tumor thrombus removal using a normothermic cardiopulmonary bypass. The bypass circuit was connected with a vacuum assisted venous drainage giving a negative pressure of 20 to 40 mm. Hg. Neither circulatory arrest nor hypothermia was used. Tumor thrombus was extracted through a longitudinal "cavotomy" and removed along with the kidney.

RESULTS

Total cardiopulmonary bypass time was 14, 19 and 22 minutes, respectively. No intraoperative or postoperative complications due to surgical technique occurred. No significant bleeding was observed at the time of cavotomy and all neoplastic tissue was removed. Pathological examination documented renal cell carcinoma in 2 cases and Wilms tumor in 1. All the patients are alive 30, 42 and 15 months, respectively, after the operation.

CONCLUSIONS

Normothermic cardiopulmonary bypass with vacuum assisted venous drainage makes circulatory arrest and hypothermia unnecessary and avoids the potential complications associated with these procedures. With respect to veno-venous shunts this technique guarantees complete surgical control of the thrombus and avoids the need for extensive dissection of the retrohepatic vena cava and Pringle maneuver.

Experience with an elective vacuum assisted cardiopulmonary bypass in the surgical treatment of renal neoplasms extending into the right atrium

PURPOSE

We evaluate the results of an elective cardiopulmonary bypass conceived to minimize the surgical risk related to its use with temporary circulatory arrest and deep hypothermia in the treatment of patients with renal tumor extending into the right atrium.

MATERIALS AND METHODS

From July 1996 to December 2000, 19 patients with renal neoplasm and venous involvement were admitted to our department. Three patients 4, 57 and 58 years old with a right (2) and left (1) renal tumor extending into the right atrium underwent radical nephrectomy and tumor thrombus removal using a normothermic cardiopulmonary bypass. The bypass circuit was connected with a vacuum assisted venous drainage giving a negative pressure of 20 to 40 mm. Hg. Neither circulatory arrest nor hypothermia was used. Tumor thrombus was extracted through a longitudinal "cavotomy" and removed along with the kidney.

RESULTS

Total cardiopulmonary bypass time was 14, 19 and 22 minutes, respectively. No intraoperative or postoperative complications due to surgical technique occurred. No significant bleeding was observed at the time of cavotomy and all neoplastic tissue was removed. Pathological examination documented renal cell carcinoma in 2 cases and Wilms tumor in 1. All the patients are alive 30, 42 and 15 months, respectively, after the operation.

CONCLUSIONS

Normothermic cardiopulmonary bypass with vacuum assisted venous drainage makes circulatory arrest and hypothermia unnecessary and avoids the potential complications associated with these procedures. With respect to veno-venous shunts this technique guarantees complete surgical control of the thrombus and avoids the need for extensive dissection of the retrohepatic vena cava and Pringle maneuver.

Bone alterations in patients with idiopathic hypercalciuria and calcium nephrolithiasis

OBJECTIVES

To verify whether alterations in bone density and turnover in patients with calcium nephrolithiasis and hypercalciuria are observable in various subgroups of patients divided according to the pathogenesis of the hypercalciuria.

METHODS

Seventy patients with calcium nephrolithiasis and idiopathic hypercalciuria, 19 to 64 years old, were assessed for spine and femur mineral metabolism and bone density using a Dexa evaluation system. After a low calcium diet, the subjects were classified into two groups: fasting hypercalciuria (FH, 39 patients) and absorptive hypercalciuria (AH, 31 patients).

RESULTS

Only in the patients with FH was the lumbar spine bone density lower than in the controls (P <0.001). Also, only the patients with FH had higher bone alkaline phosphatase and urinary hydroxyproline levels than the control group (P <0.005 and <0.015, respectively). The blood pH levels were lower, even though within the normal range, in the hypercalciuric patients than in the controls (P <0.01). There was a negative correlation between the urinary hydroxyproline level and lumbar spine and femoral neck density in patients with FH (P <0.001 and <0.005, respectively), and the blood pH correlated positively with the lumbar spine bone density.

CONCLUSIONS

Altered bone metabolism and overall bone loss were found only in the patients with FH. Overloading of acid valences, perhaps of dietary origin, could be the pathogenic factor responsible.

Bulbar urethral stricture repair with buccal mucosa graft urethroplasty

OBJECTIVES

Evaluation of the use of buccal mucosa graft as single-stage urethral reconstruction in an adult population with a stenosis of the bulbar urethra.

METHODS

In our Department between April 1996 and February 1999, 20 patients with bulbar urethra stenosis underwent single-stage urethroplasty using a buccal mucosa graft. Mean age of patients was 52 years (range 14-70). The etiology of urethral stricture was inflammation (4 cases), iatrogenic (5 cases) and idiopathic (11 cases). A ventral onlay patch (mean length 3.6 cm, range 2.5-5) was employed in all cases.

RESULTS

During the follow-up (median 13 months, range 6-28) the overall success rate was 80%. The success rate was 75% for inflammatory strictures, 80% for iatrogenic strictures and 81% for strictures of unknown etiology.

CONCLUSIONS

Although longer follow-up is needed, free graft urethroplasty with buccal mucosa graft represents a simple surgical option which has produced encouraging results. This is probably due to the quality of the tissue employed which at present seems to represent the first-choice solution in selected cases.

Bone density and skeletal metabolism are altered in idiopathic hypercalciuria

OBJECTIVE

To study bone density in hypercalciuric patients, when classified according to the main metabolic defect.

METHODS

We studied 49 patients, aged 19-60 years with calcium stones and idiopathic hypercalcuria. All subjects underwent an evaluation of mineral metabolism and a spinal and femoral DEXA measurement. Then, patients were classified as having Fasting (FH, 31 subjects) or Absorptive (AH, 18 patients) Hypercalciuria according to a standard oral calcium load.

RESULTS

Spinal bone density was lower only in FH patients as compared to controls (p <0.001). Bone alkaline phosphatase and urine hydroxyproline were higher with respect to controls only in patients with FH (p <0.005 and p <0.015, respectively). After low calcium diet, hydroxyproline excretion continued to be higher in FH patients (p <0.05). Although in the normal range, serum and urine uric acid were higher in hypercalciuric subjects (p <0.03 and p <0.005, respectively); blood pH was lower in hypercalciuric patients than in controls (p <0.01). In FH patients urine hydroxyproline negatively correlated with spinal and femoral density (p <0.001 and p <0.005, respectively), and blood pH positively correlated with spinal density.

CONCLUSIONS

a disordered bone metabolism and bone loss are present only in patients with fasting hypercalciuria. An excessive acid load, possibly of dietary origin, might be involved as a pathogenetic factor.

Metabolic complications of continent urinary diversions

The advent of modem reconstructive techniques in urologic surgery has allowed a wide use of intestinal segments in young and older patients. Intestinal conduits and reservoirs can produce a series of complications due to hydroelectrolytic disturbances, alterations of acid-base balance and of bone and hepatic metabolism, intestinal malabsorption. The severity of clinical features depends on the quantity of solute exchanges through the mucosa of the intestinal segment used and on the “age” of the conduit or reservoir.

Role of reflux prevention in urinary diversion

Considering current pathogenetical knowledge on reflux nephropathy and clinical experience with urinary diversions, it is impossible to arrive at a definitive conclusion on the necessity of reflux preventing techniques in urinary diversion. The decision has to take into account the apparent hazards of reflux in a given diversion and the apparent hazards of preventing reflux with that diversion. Whereas reflux prevention in high-pressure reservoirs and in continent diversion with cutaneous stomy is widely justified, there is no objective evidence to support the need for reflux prevention in urinary diversion with low-pressure bladder substitutes with sterile urine.

Complications of continent orthotopic urinary diversions

Although techniques for continent urinary reservoirs and neobladders are still being developed, these procedures can be performed on properly selected patients with an acceptable complication rate. A series of five continent urinary reservoir procedures are presented. Early and late complications are shown.

Endourological treatment of transitional cell tumours of the upper urinary tract

— 30 patients with transitional cell tumour of the upper urinary tract (TCTUT) underwent endourological treatment in our Institute in the last 10 years. 8 patients were submitted to percutaneous electroresection of a tumour of the renal pelvis, which was followed in 4 of them by endocavitary chemo or immunotherapy. The remaining 22 patients with tumour involving the renal pelvis (2 cases), the ureter (18 cases) and both the renal pelvis and the ureter (2 cases) were treated using electroresection, forceps removal or laser irradiation during transurethral ureterorenoscopy. The 5-year disease-free survival rate (DFS) was 27% and appeared to be lower than that of a comparable series of patients who underwent conservative open surgery. Moreover 5-year DFS was significantly higher for the patients with tumours of the renal pelvis compared to those with tumours of the pelvic ureter. Our experience confirms the feasibility of the endourological approach to TCTUT in selected cases. A rigid follow-up is suggested for the patients with a tumour involving the pelvic ureter.

Transitional cell carcinoma of the upper urinary tract: Follow-up and prognostic factors

— Of the 176 patients treated in our Institute over the last 16 years for upper tract transitional cell carcinoma (UTTCC), 155 were included in this study, 97 of whom had undergone nephroureterectomy, 28 conservative surgery and 30 endourologic treatment. The overall survival rate at 5 and 10 years was 73% and 58%, respectively. Univariate analysis of overall survival rate (O.S.) and disease-free survival rate (D.F.S.) showed no difference between patients with superficial and with invasive tumours, while multivariate analysis highlighted a difference. No difference was evident upon univariate and multivariate analysis of the patients with superficial tumours who underwent conservative (19) vs. radical (45) surgery. The same can be said for the so-called good prognosis tumours (pTa-T1-G2) and poor prognosis tumours (pT1-G3, pT2-4, G2-3) submitted to radical surgery. Overall survival was better in patients with no recurrent tumours compared to those with recurrences; furthermore prognosis was worse for patients with more than 2 recurrences. Tumour site, mono or multifocality and associated bladder tumour did not influence prognosis. Our experience confirms the basic importance of grade as a prognostic factor for UTTCC and the favourable prognosis for patients with superficial tumours, regardless of surgical technique. A rigid follow-up is mandatory for patients with more than 2 recurrences.

[Experiencing the integration between nursing teachers and nurses. A research project]

This article reports the integration experience between registered nurses and nurse educators in a teaching hospital. The study is a research with focus on the care significance to adult clients in a outpatient unit.

Transurethral laser surgery with a conventional modified resectoscope

A new 1,800-microns side fiber made of pure silica with laser beam deviation of 82 degrees and divergence of 18 degrees was inserted into a modified transurethral resectoscope and used to treat in vitro some prostates removed during radical prostatectomy. Sterilization of prostatic tissue with a depth of penetration of 12 mm was observed after treatment with 20 W for 2 min. Irradiation with 60 W for 1 min produced vaporization and explosion of the tissue and a depth of penetration of 15 mm. The laser resectoscope was then successfully employed for the treatment of 6 cases of benign prostatic hyperplasia (BPH) as well as in high risk patients with bulky bleeding bladder tumors (4 cases) and with transitional carcinoma of the prostate invading the parenchyma (2 cases). 3 patients with small size BPH underwent only laser irradiation. All others were submitted to traditional transurethral resection followed by laser treatment with Nd: YAG using the same instrument. Our laser resectoscope lowers costs since the side fiber is reusable for 4-5 treatments and brings laser treatment nearer to traditional endoscopic treatment, thereby making its application more comfortable for the urologist.

Photosensitization of cystine stones to induce laser lithotripsy

We report the preliminary results of laser lithotripsy of cystine stones accomplished in 2 patients with the use of a new method of photosensitization. Transurethral rigid ureterorenoscopy was performed with an 8.5F instrument to reach 0.8 and 1.8 cm. stones located in the right and left lumbar ureters, respectively. A 320 mu. fiber was then inserted and pushed into contact with the stone. Then, 400 preliminary impulses were released from a pulsed dye laser (504 nm) with energy output at 140 mJ. and at a rate of 5 Hz. without any visible modification of the stone structure. The saline solution used as irrigation fluid was then substituted with a 2% solution of rifamycin. Totals of 95 and 152 impulses released at the same energy output previously used were then sufficient to produce a satisfactory fragmentation of the stone in both cases. Sonography and excretory urography showed no alterations of the treated urinary tract in either case. The use of rifamycin in the irrigation fluid is suggested for laser treatment of hard or nonabsorbent stones, since this substance favors optical coupling and lowers the threshold of plasma formation on the surface of the stone.

Percutaneous Bcg Treatment in Superficial Transitional Cell Cancer of the Upper Urinary Tract

From January 1989 to September 1992, 5 patients (age 58–68 years) were treated with percutaneous Pasteur BCG for superficial transitional cell carcinoma of the upper urinary tract. In 4 cases BCG was prophylactic after endourological resection of the tumors. In one case of bilateral Tis of the upper urinary tract, BCG was administered for therapeutical purposes. Every patient received 375 mg Pasteur BCG in 250 ml saline, every 2 weeks for 6 consecutive weeks in 2 patients, 5 weeks in 1, and 4 in 2. No major complications were observed. After a median follow-up of 10.2 months, 4 patients are disease free, 1 patient underwent nephroureterectomy. Percutaneous BCG in upper tract superficial transitional cell cancer seems a feasible option in selected cases.

Five years experience in experimental laser lithotripsy

In the first part of our experience approximately 300 stones of different composition have been treated in vitro with three different laser sources: Nd-YAG laser (1,064 nm), dye laser (504 nm) and alexandrite laser (755 nm). Calcium oxalate monohydrate and brushite stones appeared to be the most resistant to lithotripsy. Highest fragmentation rates were obtained for calcium oxalate dihydrate stones followed by struvite, uric acid and hydroxyapatite stones. The Nd-YAG laser did not appear to be ideal for lithotripsy since early damage to the fiber tip was observed when this source was used. Both the dye and the alexandrite lasers were almost always effective in fragmenting the various types of stones. We subsequently treated some cystine stones while immersed in water or in solutions of carmine indigo (2%), methylene blue (5%), rifamycin (0.6 and 6%) and rifampicin (0.8 and 0.3%) with the dye or the alexandrite laser. The spectra of these solutions, previously analyzed with the spectrophotometer, showed that rifamycin and rifampicin absorbed large amounts of light radiation at the wave length of the dye laser (504 nm). Successful fragmentation occurred only when the dye laser was used to treat stones immersed in the more concentrated solutions of these two substances. The quantity of fragmented material after treating a 10-cm3 cystine stone previously immersed in the more concentrated solutions of rifamycin and rifampicin (30 and 10 mm3, respectively) confirmed previous results.(ABSTRACT TRUNCATED AT 250 WORDS)

Possible link between vitamin D and hyperoxaluria in patients with renal stone disease

1. Vitamin D seems to play an essential role in the pathogenesis of idiopathic hypercalciuria at least in part via intestinal hyperabsorption of calcium. Hyperabsorption of calcium, in turn, might enhance the intestinal uptake of free oxalate, thus leading to hyperoxaluria. To verify this hypothesis we studied 75 calcium-stone-formers subdivided as follows: group 1 (15 patients) with isolated hyperoxaluria; group 2 (25 patients) with hyperoxaluria and hypercalciuria; group 3 (22 patients) with isolated hypercalciuria; group 4 (12 patients) with no metabolic abnormalities. 2. As expected, urinary calcium excretion differed in the various groups (P < 0.001), being highest in groups 2 and 3; urinary oxalate excretion, by definition highest in groups 1 and 2, was even more pronounced in group 2 than in group 1 (P < 0.05). Although in the normal range, the serum 1,25-dihydroxyvitamin D concentration was higher (P < 0.001) in the two hypercalciuric groups (2 and 3), showing peak levels in group 2. 3. When the data from the 75 stone-formers were pooled, there was a positive correlation between the serum concentration of 1,25-dihydroxyvitamin D and urinary calcium excretion (P < 0.001) and urinary oxalate excretion (P < 0.003), the latter relationship also being present when only the two hypercalciuric groups (groups 2 and 3) were considered together (P < 0.05). 4. Our data seem to confirm a relevant role for the vitamin D system in the pathogenesis of calcium nephrolithiasis due to increased intestinal calcium absorption, but also because this in turn induces a greater intestinal absorption of oxalate, thus leading to the occurrence or exacerbation of hyperoxaluria.

Conservative nephrolithiasis treatment in pediatrie age

At the Urological Institute of Padua University, from January 1985 to February 1990, 38 children with nephrolithiasis were treated with PCNL, ESWL or URS, for a total of 40 renal units. Stone-free status was achieved in 13/14 renal units treated with PCNL, in 15/22 renal units treated with ESWL. A retreatment with ESWL was necessary in 4 cases. Our follow up ranges from 3 to 42 months with an average of 30 months.

The case for a percutaneous approach to transitional cell carcinoma of the renal pelvis

Percutaneous treatment of transitional cell carcinoma of the renal pelvis in 4 patients is reported. The presenting symptom was hematuria in 2 patients, while in 2 diagnosis was made by chance at excretory urography. Endoscopic removal of the tumor was not possible in the 2 patients who underwent transurethral ureteroscopy due to the location of the lesion. Percutaneous electroresection of the tumor was performed after puncture of an inferior (3 patients) or middle (1) calix and dilation of the nephrostomy tract up to 30F. Pathological findings revealed a grade 1 papillary carcinoma in 3 patients and a well differentiated inverted papilloma in 1. A single-J ureteral catheter was left in place after the procedure. Cytological, radiographic and endoscopic studies were negative 11, 13, 18 and 24 months after the treatment, respectively. We believe that the percutaneous approach is a feasible option in cases of small, single, low grade lesions not removable via ureteroscopy, particularly in patients at high surgical risk.

Pediatric nephroscope for percutaneous renal stone removal

A new 17-F nephroscope was used for percutaneous renal stone management. It appeared useful in reducing the possible main vascular injuries after percutaneous nephrolithotomy. Personal experience with pediatric as well as selected adult cases is presented.

Short-term and stabilized effects of percutaneous nephrolithotomy on the kidney

A homogeneous group of 15 patients was investigated before and after percutaneous nephrolithotomy (PCN). Creatinine and electrolyte clearances evaluated both before and during saline (NaCl 0.9%) infusion, 4-7 days after PCN remained unchanged with respect to the preoperative values. A significant decrease of urinary PGE2 was observed postoperatively both before and after extracellular volume expansion. 99mTc-DTPA renography performed 26-40 days after surgery showed a scar on the convex margin of one kidney in the area of the nephrostomy and an improved renographic curve in 5 renal units. No difference between pre- and post-PCN isotopic clearances was evident. On the basis of our results we can affirm that PCN is an efficient and safe method for the treatment of nephrolithiasis.

Urethrogluteal fistula occurring after radical cystectomy for bladder cancer

We report on a patient who developed a urethrogluteal fistula 11 years following cystectomy performed for carcinoma of the bladder. The diagnosis was established by retrograde urethrography and fistulography. To the best of our knowledge, no previous case has been reported in the literature.

Role of the diuresis renogram in the study of the pelviureteric junction

A consecutive series of 29 patients (33 pelviureteric units) with urographic signs of altered passage through the pelviureteric junction underwent diuresis renography performed by means of an intravenous injection of 99mTc-diethylenetriamine pentaacetic acid/kg body weight followed by intravenous administration of frusemide. Anderson-Hynes pyeloplasty was performed in 19 pelviureteric units with a modest or almost absent fall in the renographic curve after diuretic injection; 2 other symptomatic patients, in whom a moderate fall of the same curve was found also underwent surgery. Complete normalization of the renogram was observed in 17 of 21 operated patients. Severe functional deficit and polymegacalicosis were evident in 3 and 1 patient, respectively, with unchanged postoperative renograms. During follow-up (6 months to 2 years) diuresis renography remained unaltered in non-operated units. Our experience indicates how the diuresis renogram not only gives functional confirmation of a pelviureteric junction obstruction, but is also helpful in resolving situations in which there is a discrepancy between symptoms and urographic signs. Furthermore it provides an accurate method for evaluating the results of pyeloplasty. However, the use of this investigation is not, in our opinion, indicated in the presence of severe functional deficit of the kidney or pyelectasis.

Parathyroid localization in primary hyperparathyroidism: double-tracer scintigraphy and venous sampling techniques combined. A first evaluation

The authors report their first experience with two techniques for preoperative localization of hyperfunctioning parathyroid glands: double-tracer (99mTc-201Tl) scintigraphy and venous sampling from thyroid veins. Nineteen patients affected by primary hyperparathyroidism were examined by both methods and subsequently submitted to surgery. Scintigraphy showed a sensitivity of 77.3% while the positivity of sampling was 63.6%; with the two techniques combined a correct localization was obtained in 90.9% of all cases. The authors emphasize the usefulness of both methods combined for locating enlarged hyperfunctioning parathyroids.

The evolution of renal function after surgical treatment of malignant lithiasis with severely compromised renal function

16 patients with calcic nephrolithiasis and renal failure were admitted to our institute and underwent surgery. 4 patients had bilateral nephrolithiasis and 12 cases had relapsed. Selective nephrotomy was performed in all cases, pyelotomy was done in 8 and partial nephrectomy in 2 patients. In 8 patients renal function improved but no difference was observed in 6 patients. Renal function worsened in 2 patients who had shown significant preoperative proteinuria. According to our experience, the success of this therapy depends on: (1) accurate patient selection; (2) adequate preoperative treatment, and (3) personalization of surgical management.