A Phospholipid Profile at 4 Months Predicts the Onset of Celiac Disease in at-Risk Infants

Celiac disease (CeD) is a multifactorial disease influenced by both genetic and environmental risk factors. CeD genetic components are mainly due to HLA class II genes, which account for approximately 40% of the disease heritability. The environmental factor is linked to gliadin ingestion. Despite genetic and epigenetic studies, the pathological molecular mechanism remains unclarified. The strong genetic component does not explain more than half of the hereditability; we identified several epigenetic features that contribute to the understanding of the missing hereditability. The lipid profile of infants has been proposed as a potential biomarker of CeD metabolism that can be measured before they exhibit developmental disorders and clinical symptoms. We suggest that the state of the host is a main factor for the abnormal immune response to gluten. Long before any exposure to the offending agent or any production of specific antibodies, several molecular mechanisms are differentially expressed in infants who will develop CeD compared to their peers matched for the same genetic profile. The present study explored the serum phospholipid profile of a group of infants at risk for celiac disease, followed up to 8 years to monitor the onset of CeD. We compared 30 patients who developed the disease with 20 age- and sex-matched peers with similar genetic profiles who did not develop the disease within 8 years. Serum phospholipids were analysed at 4 months, before exposure to gluten, and at 12 months of age, when none showed any marker of disease. In the 30 CeD patients, we also analysed the serum at the time of diagnosis (>24 months). The serum phospholipid profile was fairly constant across 4 and 12 months of age and, in CeD, up to 24–36 months. The phospholipid signature was dramatically different in infants who developed CeD when compared to that of control NY-CeD (Not Yet developing Celiac Disease) peers. We identified a specific serum phospholipid signature that predicts the onset of celiac disease in HLA at-risk infants years before the appearance of antibodies specific for CeD in the serum and before any clinical symptoms, even before gluten introduction into the diet at 4 months. Specifically, lysophosphatidylcholine, phosphatidylcholine, alkylacyl-phosphatidylcholine, phosphoethanolamines, phosphatidylserines, phosphatidylglycerol and phosphatidylinositol were found to be differentially represented in CeD versus NY-CeD. A set constituted by a limited number of alkylacyl-phosphatidylcholine and lyso-phosphatidylcholine, together with the duration of breast-feeding, allows the discrimination of infants who develop celiac disease before 8 years of age from those at a similar genetic risk who do not develop the disease. In addition to recent discovery, our paper unveiled a specifc phopholipid profile, able to discriminate infants who eventually develop celiac disease years before antibodies or clinical symptoms ensue.

Rirs through Semi-Rigid Ureteroscope and Holmium Laser in the Treatment of Ureteral Stones Retropulsion

Retrograde displacement of ureteral stones into the renal cavities during ureteroscopic lithotripsy represents a frequent and adverse event that leads to additional procedures (ESWL, PCNL, Retrograde Intra-renal lithotripsy with flexible instruments, DJ stent placement and subsequent EWSL) to obtain full clearence of calculi. All these procedures require a further time of treatment.

Between 1/2008 and 3/2009, a total of 48 patients harbouring proximal (21 cases) and distal (27 cases) ureteral stones underwent Holmium Laser lithotripsy. In 3 patients previous percutaneous nephrostomy was performed to drain the excretory way. In 12 cases (25%) stone retropulsion occurred; in 3 patients in the upper calix and in 5 in the renal pelvis. Only in 4 cases the stone migrated in the lower or medium calix. In 8 cases we attempted the immediate treatment of intrarenal displaced stones by advancing the semi-rigid instrument into the renal cavities. In 2 cases the treatment aborted because of the shortness of ureteroscope. The instillation of lubricating lidocaine jelly prevented in 3 cases furher displacement of stone. Washing with saline solution through nephrostomic catheter allowed an effective mobilization of stone and an easy lasertripsy

RIRS was successful in 4 cases. When flexible devices or immediate ESWL are not available, rigid or semi-rigid retrograde lithotripsy with holmium laser immediately performed after ureteral stone displacement represents a safe and effective method to treat displaced stones. Several tricks are required to obtain a good stone-free rate.

Neuroendocrine Small-Cell Bladder Cancer: Our Experience

Introduction

Neuroendocrine bladder cancer is extremely rare, with an estimated incidence of 0.35–0.70% of all bladder tumors. The small-cell carcinoma represents the most frequent histologic variant described. Small-cell carcinoma is an epithelial tumor associated with a more aggressive behavior and poorer prognosis than transitional cell bladder carcinoma. The overall survival rate at 5 years does not exceed 8%. At the time of presentation 59% of patients have clinical stage >T2 and 56% show metastatic disease. In 50% of the patients, fatal progression occurrs within 6 months. Local recurrence after radical surgery occurred in 50–70% of cases.

Patients and Methods

We report three cases of pure neuroendocrine small-cell bladder cancer. Hematuria was the most common presenting symptom. Local advanced disease was present in all the cases with stage >T2, metastatic disease in 1 case, lymph node involvement and ureteral bilateral obstruction in 2. Two patients were treated by radical cystectomy, bilateral pelvic limph node resections and urinary derivation. Platinum-based adjuvant chemotherapy was proposed but only two patients received the treatment. One patient with liver metastasis was managed only by extensive TUR and support regimen.

Results

In 2 patients residual or relapsed cancer reappered within 2 months after surgery. All of the three patients died of metastatic disease at 5, 7, and 13 months. Median overall survival was 7 months. The most common site of relapse and spread of disease was the peritoneum and intestinal tract, and the reason of death was uncontrolled acute hemorrhage from gastro-intestinal district.

Conclusions

In the absence of a prospective study, and because of the rarity of the disease, the best treatment for small-cell bladder cancer remains uncertain. Neoadjuvant chemoterapy with platinum regimen plus aggressive surgical approach will be the treatment of choice. The association of chemotherapy and radiotherapy should also be considered.

[Urethral recurrence of invasive carcinoma following BCG treatment for bladder Ca in situ]

CIS is a flat, high-grade, non-invasive microscopic urothelial carcinoma. It is considered a precursor of invasive bladder cancer. CIS is classified as primary, secondary or concurrent, when occurred as isolated CIS without cuncurrent papillary tumors, or detected during the follow-up of patients with a previous papillary tumor, or finally in the presence of bladder neoplasm. BCG is widely established as the treatment of choice for CIS with a success rate of approximately 70%. BCG reduces the risk of progression of CIS into invasive carcinoma in 30 to 50% of cases. Direct and prolonged contact between the urothelium and BCG is a prerequisite for successful therapy. Discovery of CIS in the prostatic or membranous urethra represents an ominous sign. CIS may be present only in the epithelial lining of the prostatic urethra or in the ducts, or in the worst case it may be found in the prostatic tissue stroma. Urethral involvement by CIS is at high risk of tumor progression and development of metastases due to reduced thickness of lamina propria and absence of muscolaris mucosa. 83 patients, enrolled from 1/1996 to 12/2005 at our urological department with CIS: primary (focal and multifocal) in 25, secondary in 7 and cuncurrent in 51 (associated with T1bG3 cancer in 37 cases), and urethral CIS in 5 and conservatively treated by TUR and intravescical instillations of BCG, 4 developed afterwords only invasive cancer of the urethra in the absence of bladder involvement. In 2 cases cancer arised from the prostatic fossa after TURP, in 1 from membranous urethra and in the last from prostatic ducts. Among the 4 patients, 3 were treated by cystoprostatourethrectomy and Platinum-based chemotherapy, 1 refused surgical treatment. Two patients died for disseminated disease. 1 patient is alive at 60-month's follow-up. In the last patient cancer relapsed at 36-month's follow-up. We conclude that prostatic/urethral involvement during follow-up after successful intravesical treatment with BCG in CIS represents a high risk of developing invasive and incontrolled cancer. A careful watch is recommended in these patients.

[RIRS through semi-rigid ureteroscope and holmium laser in the treatment of ureteral stones retropulsion]

Retrograde displacement of ureteral stones into the renal cavities during ureteroscopic lithotripsy represents a frequent and adverse event that leads to additional procedures (ESWL, PCNL, Retrograde Intra-renal lithotripsy with flexible instruments, DJ stent placement and subsequent EWSL) to obtain full clearence of calculi. All these procedures require a further time of treatment. Between 1/2008 and 3/2009, a total of 48 patients harbouring proximal (21 cases) and distal (27 cases) ureteral stones underwent Holmium Laser lithotripsy. In 3 patients previous percutaneous nephrostomy was performed to drain the excretory way. In 12 cases (25%) stone retropulsion occurred; in 3 patients in the upper calix and in 5 in the renal pelvis. Only in 4 cases the stone migrated in the lower or medium calix. In 8 cases we attempted the immediate treatment of intrarenal displaced stones by advancing the semi-rigid instrument into the renal cavities. In 2 cases the treatment aborted because of the shortness of ureteroscope. The instillation of lubricating lidocaine jelly prevented in 3 cases furher displacement of stone. Washing with saline solution through nephrostomic catheter allowed an effective mobilization of stone and an easy lasertripsy. RIRS was successful in 4 cases. When flexible devices or immediate ESWL are not available, rigid or semi-rigid retrograde lithotripsy with holmium laser immediately performed after ureteral stone displacement represents a safe and effective method to treat displaced stones. Several tricks are required to obtain a good stone-free rate.

Urethral Recurrence of Invasive Carcinoma following BCG Treatment for Bladder Ca in Situ

CIS is a flat, high-grade, non-invasive microscopic urothelial carcinoma. It is considered a precursor of invasive bladder cancer. CIS is classified as primary, secondary or concurrent, when occurred as isolated CIS without cuncurrent papillary tumors, or detected during the follow-up of patients with a previous papillary tumor, or finally in the presence of bladder neoplasm. BCG is widely established as the treatment of choice for CIS with a success rate of approximately 70%. BCG reduces the risk of progression of CIS into invasive carcinoma in 30 to 50% of cases. Direct and prolonged contact between the urothelium and BCG is a prerequisite for successful therapy. Discovery of CIS in the prostatic or membranous urethra represents an ominous sign. CIS may be present only in the epithelial lining of the prostatic urethra or in the ducts, or in the worst case it may be found in the prostatic tissue stroma. Urethral involvement by CIS is at high risk of tumor progression and development of metastases due to reduced thickness of lamina propria and absence of muscolaris mucosa. 83 patients, enrolled from 1/1996 to 12/2005 at our urological department with CIS: primary (focal and multifocal) in 25, secondary in 7 and cuncurrent in 51 (associated with T1bG3 cancer in 37 cases), and urethral CIS in 5 and conservatively treated by TUR and intravescical instillations of BCG, 4 developed after words only invasive cancer of the urethra in the absence of bladder involvement. In 2 cases cancer arised from the prostatic fossa after TURP, in 1 from membranous urethra and in the last from prostatic ducts. Among the 4 patients, 3 were treated by cystoprostatourethrectomy and Platinum-based chemotherapy, 1 refused surgical treatment. Two patients died for disseminated disease. 1 patient is alive at 60–month's follow-up. In the last patient cancer relapsed at 36–month's follow-up. We conclude that prostatic/urethral involvement during follow-up after successful intravesical treatment with BCG in CIS represents a high risk of developing invasive and incontrolled cancer. A careful watch is recommended in these patients.

[Neuroendocrine small-cell bladder cancer: our experience]

INTRODUCTION

Neuroendocrine bladder cancer is extremely rare, with an estimated incidence of 0.35-0.70% of all bladder tumors. The small-cell carcinoma represents the most frequent histologic variant described. Small-cell carcinoma is an epithelial tumor associated with a more aggressive behavior and poorer prognosis than transitional cell bladder carcinoma. The overall survival rate at 5 years does not exceed 8%. At the time of presentation 59% of patients have clinical stage >T2 and 56% show metastatic disease. In 50% of the patients, fatal progression occurs within 6 months. Local recurrence after radical surgery occurred in 50-70% of cases.

PATIENTS AND METHODS

We report three cases of pure neuroendocrine small-cell bladder cancer. Hematuria was the most common presenting symptom. Local advanced disease was present in all the cases with stage >T2, metastatic disease in 1 case, lymph node involvement and ureteral bilateral obstruction in 2. Two patients were treated by radical cystectomy, bilateral pelvic limph node resections and urinary derivation. Platinum-based adjuvant chemotherapy was proposed but only two patients received the treatment. One patient with liver metastasis was managed only by extensive TUR and support regimen.

RESULTS

In 2 patients residual or relapsed cancer reappered within 2 months after surgery. All of the three patients died of metastatic disease at 5, 7, and 13 months. Median overall survival was 7 months. The most common site of relapse and spread of disease was the peritoneum and intestinal tract, and the reason of death was uncontrolled acute hemorrhage from gastro-intestinal district.

CONCLUSIONS

In the absence of a prospective study, and because of the rarity of the disease, the best treatment for small-cell bladder cancer remains uncertain. Neoadjuvant chemotherapy with platinum regimen plus aggressive surgical approach will be the treatment of choice. The association of chemotherapy and radiotherapy should also be considered.

Partial purification and MALDI-TOF MS analysis of UN1, a tumor antigen membrane glycoprotein

UN1 is a membrane glycoprotein that is expressed in immature human thymocytes, a subpopulation of peripheral T lymphocytes, the HPB acute lymphoblastic leukemia (ALL) T-cell line and fetal thymus. We previously reported the isolation of a monoclonal antibody (UN1 mAb) recognizing the UN1 protein that was classified as "unclustered" at the 5th and 6th International Workshop and Conference on Human Leukocyte Differentiation Antigens. UN1 was highly expressed in breast cancer tissues and was undetected in non-proliferative lesions and in normal breast tissues, indicating a role for UN1 in the development of a tumorigenic phenotype of breast cancer cells. In this study, we report a partial purification of the UN1 protein from HPB-ALL T cells by anion-exchange chromatography followed by immunoprecipitation with the UN1 mAb and MALDI-TOF MS analysis. This analysis should assist in identifying the amino acid sequence of UN1.

The Role of Partial Cystectomy in the Treatment of Muscle-Invasive Bladder Cancer

Partial cystectomy has been widely performed in the treatment of muscle-invasive bladder cancer in the 1960s and 70s. During the 1970s and 80s a more aggressive surgical approach was advocated by urologists. However, major complications occurred in 4–25% of patients undergoing radical cystectomy and urinary diversion. The overall survival in patients managed by radical cystectomy has increased during the last decades, but disease-free survival remains the same. This procedure allows excellent loco-regional tumor control, but not changes in the timing of distant metastases and in the failure to control the disease. Recently, multimodal strategies in sparing bladder surgery have been proposed. Neoadjuvant chemotherapy, with or without irradiation, allows bladder sparing surgery in selected patients. A literature review demonstrates a later recurrence in the preserved bladder ranging from 40–75%. One-third of these recurrences required cystectomy and 15–20% of cases with bladder preservation experienced disease progression and died of cancer within 2 yrs. Only 40 and 20% of T2-T3 bladder cancer patients are alive and disease-free at 5 and 10 yrs of follow-up, respectively. In our experience, in selected patients, disease-free survival, overall survival, time to progression and final bladder preservation rate was higher compared to other patients. Bladder sparing in selected patients, i.e. single non-recurrent neoplasm, favorable site, no prostatic or urethral involvement, complete response to neoadjuvant chemotherapy, no P53 overexpression, no previous BCG-failure, is a feasible approach. Cystectomy, possibly with neobladder tailoring, is currently, the standard therapy for muscle-invasive bladder cancer. A better understanding of bladder tumor disease is necessary to choose the optimal treatment and to control each individual patient.

Slow folding of three-fingered toxins is associated with the accumulation of native disulfide-bonded intermediates

Snake neurotoxins are short all-beta proteins that display a complex organization of the disulfide bonds: two bonds connect consecutive cysteine residues (C43-C54, C55-C60), and two bonds intersect when bridging (C3-C24, C17-C41) to form a particular structure classified as "disulfide beta-cross". We investigated the oxidative folding of a neurotoxin variant, named alpha62, to define the chemical nature of the three-disulfide intermediates that accumulate during the process in order to describe in detail its folding pathway. These folding intermediates were separated by reverse-phase HPLC, and their disulfide bonds were identified using a combination of tryptic hydrolysis, manual Edman degradation, and mass spectrometry. Two dominant intermediates containing three native disulfide bonds were identified, lacking the C43-C54 and C17-C41 pairing and therefore named des-[43-54] and des-[17-41], respectively. Both species were individually allowed to reoxidize under folding conditions, showing that des-[17-41] was a fast-forming nonproductive intermediate that had to interconvert into the des-[43-54] isomer before forming the native protein. Conversely, the des-[43-54] intermediate appeared to be the immediate precursor of the oxidized neurotoxin. A kinetic model for the folding of neurotoxin alpha62 which fits with the observed time-course accumulation of des-[17-41] and des-[43-54] is proposed. The effect of turn 2, located between residues 17 and 24, on the overall kinetics is discussed in view of this model.

Pro-sequence assisted folding and disulfide bond formation of human nerve growth factor

Nerve growth factor (NGF) is a member of the neurotrophin family. These growth factors support neuronal survival and differentiation. Neurotrophins are synthesized as pre-pro-proteins. Whereas the pre-sequences mediate secretion, the function of the pro-peptides is largely unknown. To test the role of the pro-sequence as a folding enhancer, recombinant human pro-NGF (rh-pro-NGF) was produced in Escherichia coli. The oxidative refolding of rh-pro-NGF and rh-NGF was studied using electrospray mass spectrometry (ESIMS) time-course analysis. This analysis permitted both the identification and quantification of intermediates present during the process. The disulfide bonds formed at different times of the refolding processes were characterized by proteolytic digestion followed by matrix assisted laser desorption ionization mass spectrometry (MALDIMS) analysis. Folding yields and kinetics of rh-pro-NGF were significantly enhanced when compared to the in vitro refolding of mature rh-NGF. These results suggest that the pro-sequence of NGF promotes folding of the mature part.

Effect of deamidation on folding of ribonuclease A

The folding of ribonuclease A (RNase A) has been extensively studied by characterizing the disulfide containing intermediates using different experimental conditions and analytical techniques. So far, some aspects still remain unclear such as the role of the loop 65-72 in the folding pathway. We have studied the oxidative folding of a RNase A derivative containing at position 67 the substitution Asn --> isoAsp where the local structure of the loop 65-72 has been modified keeping intact the C65-C72 disulfide bond. By comparing the folding behavior of this mutant to that of the wild-type protein, we found that the deamidation significantly decreases the folding rate and alters the folding pathway of RNase A. Results presented here shed light on the role of the 65-72 region in the folding process of RNase A and also clarifies the effect of the deamidation on the folding/unfolding processes. On a more general ground, this study represents the first characterization of the intermediates produced along the folding of a deamidated protein.

Characterization of five new low-molecular-mass trypsin inhibitors from white mustard (Sinapis alba L.) seed

Five new low-molecular-mass trypsin inhibitors belonging to the RTI/MTI-2 family were identified from white mustard (Sinapis alba L. ; MTI-2) seed. Purified MTI-2 consisted of a peptide mixture, displaying Ile or Arg at position 43, Trp or kynurenine (Kyn) at position 44, and C-terminal ragged ends. The occurrence of Ile or Arg at position 43 suggested that MTI-2 inhibitors originated from different genes. The presence of 5-oxo-proline (pyroglutamic acid; 5-oxoPro1) and Kyn44 reflected post-translational processing of the serine proteinase inhibitor. MTI-2 showed approximately 70% amino-acid identity with low-molecular-mass trypsin inhibitors isolated from oil rape (Brassica napus var. oleifera; RTI-III) seed and with serine proteinase inhibitors mapped in Arabidopsis thaliana chromosome II (ATTI). Furthermore, MTI-2 was homologous to brazzein, the sweet-tasting protein from Pentadiplandra brazzeana Baillon fruit ( approximately 30% amino-acid identity). Although snake-venom toxins showed a low amino-acid identity (< 20%) with MTI-2, RTI-III, and ATTI, some structurally relevant residues were conserved. The disulfide bridge pattern of MTI-2 (Cys5-Cys27, Cys18-Cys31, Cys42-Cys52, and Cys54-Cys57) corresponded to that of RTI-III and of snake-venom toxins, being different from that of brazzein. Therefore, protein similarity might be attributable to the three-dimensional arrangement rather than to the amino-acid sequence. Values of Ka for MTI-2 binding to bovine beta-trypsin (trypsin) and bovine alpha-chymotrypsin were 6.3 x 109 M-1 and 2.0 x 106 M-1, respectively, at pH 8.0 and 21.0 degrees C. Moreover, values of kon for MTI-2 binding to trypsin and of koff for the dissociation of the serine proteinase:inhibitor complex were 5.6 x 105 M-1.s-1 and 8.9 x 10-5 M-1.s-1, respectively, at pH 8.0 and 21.0 degrees C. Despite the heterogeneity of the purified inhibitor peptide mixture, the inhibition properties of the different MTI-2 inhibitors were indistinguishable.

Lithotripsy in the treatment of urinary lithiasis

Based on an extensive review of the literature and on our own clinical experience, this article attempts to present clear guidelines for the management of various kidney stones, particularly regarding the extracorporeal shock waves lithotripsy (ESWL) treatment nowadays. Few technical developments have changed medicine more within a short period of time than ESWL. Fifteen years after the first clinical application, ESWL has gained world-wide acceptance as first choice therapy for most forms of urolithiasis. Ninety-eight per cent of stones can be successfully fragmented by the application of shock-waves, but the ability of the kidney and ureter to clear the resulting fragments is far more important in terms of successful treatment outcome. Increasing experience with new ultrasound-guided lithotriptors has shown that there are some advantages: cost reduction, permanent monitoring and lack of exposure to ionising radiations. ESWL is a safe procedure for the treatment of urolithiasis; nevertheless some problems remain. In ureteric stones, ureteroscopy (rigid or flexible device) allows a rate of stone-free patients better than ESWL. For treatment of large staghorn calculi combined approach of PCNL and ESWL is preferred. For stones located at lower calyx, the stone-free rate in patients treated by ESWL fell to 50%, when unfavourable anatomy is present. The potential long-term renal damage, associated with ESWL in children, have delayed the acceptance of shock-waves into paediatric practice. Recent reports suggest that the renal damage, including the potential risk of hypertension induced by ESWL, is mild and transient. A subgroup of patients (e.g. solitary kidney, impaired renal function, children) required further attention. The fate of residual fragments is unclear. In some cases residual lithiasis tend to result in regrowth and further progression, although ESWL itself does not increase the recurrence rate of urolithiasis. Nevertheless follow-up of stone patients after ESWL is mandatory and the ultimate goal of treating stones by whatever means is to get the patient stone-free and prevent recurrence.

Contribution of individual disulfide bonds to the oxidative folding of ribonuclease A

The eight cysteine residues of ribonuclease A form four disulfide bonds in the native protein. We have analyzed the folding of three double RNase A mutants (C65A/C72A, C58A/C110A, and C26A/C84A, lacking the C65-C72, C58-C110, and C26-C84 disulfide bonds, respectively) and two single mutants (C110A and C26A), in which a single cysteine is replaced with an alanine and the paired cysteine is present in the reduced form. The folding of these mutants was carried out in the presence of oxidized and reduced glutathione, which constitute the main redox agents present within the ER. The use of mass spectrometry in the analysis of the folding processes allowed us (i) to follow the formation of intermediates and thus the pathway of folding of the RNase A mutants, (ii) to quantitate the intermediates that formed, and (iii) to compare the rates of formation of intermediates. By comparison of the folding kinetics of the mutants with that of wild-type RNase A, the contribution of each disulfide bond to the folding process has been evaluated. In particular, we have found that the folding of the C65A/C72A mutant occurs on the same time scale as that of the wild-type protein, thus suggesting that the removal of the C65-C72 disulfide bond has no effect on the kinetics of RNase A folding. Conversely, the C58A/C110A and C26A/C84A mutants fold much more slowly than the wild-type protein. The removal of the C58-C110 and C26-C84 disulfide bonds has a dramatic effect on the kinetics of RNase A folding. Results described in this paper provide specific information about conformational folding events in the regions involving the mutated cysteine residues, thus contributing to a better understanding of the complex mechanism of oxidative folding.

Early intermediates in the PDI-assisted folding of ribonuclease A

The oxidative refolding of ribonuclease A has been investigated in several experimental conditions using a variety of redox systems. All these studies agree that the formation of disulfide bonds during the process occurs through a nonrandom mechanism with a preferential coupling of certain cysteine residues. We have previously demonstrated that in the presence of glutathione the refolding process occurs through the reiteration of two sequential reactions: a mixed disulfide with glutathione is produced first which evolves to form an intramolecular S-S bond. In the same experimental conditions, protein disulfide isomerase (PDI) was shown to catalyze formation and reduction of mixed disulfides with glutathione as well as formation of intramolecular S-S bonds. This paper reports the structural characterization of the one-disulfide intermediate population during the oxidative refolding of Ribonuclease A under the presence of PDI and glutathione with the aim of defining the role of the enzyme at the early stages of the reaction. The one-disulfide intermediate population occurring at the early stages of both the uncatalyzed and the PDI-catalyzed refolding was purified and structurally characterized by proteolytic digestion followed by MALDI-MS and LC/ESIMS analyses. In the uncatalyzed refolding, a total of 12 disulfide bonds out of the 28 theoretical possible cysteine couplings was observed, confirming a nonrandom distribution of native and nonnative disulfide bonds. Under the presence of PDI, only two additional nonnative disulfides were detected. Semiquantitative LC/ESIMS analysis of the distribution of the S-S bridged peptides showed that the most abundant species were equally populated in both the uncatalyzed and the catalyzed process. This paper shows the first structural characterization of the one-disulfide intermediate population formed transiently during the refolding of ribonuclease A in quasi-physiological conditions that mimic those present in the ER lumen. At the early stages of the process, three of the four native disulfides are detected, whereas the Cys26-Cys84 pairing is absent. Most of the nonnative disulfide bonds identified are formed by nearest-neighboring cysteines. The presence of PDI does not significantly alter the distribution of S-S bonds, suggesting that the ensemble of single-disulfide species is formed under thermodynamic control.

Comparison of the kinetics of S-S bond, secondary structure, and active site formation during refolding of reduced denatured hen egg white lysozyme

To investigate the role of some tertiary interactions, the disulfide bonds, in the early stages of refolding of hen lysozyme, we report the kinetics of reoxidation of denatured and reduced lysozyme under the same refolding conditions as those previously used to investigate the kinetics of regain of its circular dichroism (CD), fluorescence, and activity. At different stages of the refolding, the oxidation of the protein was blocked by alkylation of the free cysteines with iodoacetamide and the various oxidation states present in the samples were identified by electrospray-mass spectrometry. Thus, it was possible to monitor the appearance and/or disappearance of the species with 0 to 4 disulfide bonds. Using a simulation program, these kinetics were compared with those of regain of far-UV CD, fluorescence, and enzymatic activity and were discussed in terms of a refined model for the refolding of reduced hen egg white lysozyme.

Characterization of low-molecular-mass trypsin isoinhibitors from oil-rape (Brassica napus var. oleifera) seed

A new low-molecular-mass (6767.8 Da) serine proteinase isoinhibitor has been isolated from oil-rape (Brassica napus var. oleifera) seed, designated 5-oxoPro1-Gly62-RTI-III. The 5-oxoPro1-Gly62-RTI-III isoinhibitor is longer than the Asp2-Pro61-RTI-III and the Ser3-Pro61-RTI-III forms, all the other amino acid residues being identical. In RTI-III isoinhibitors, the P1-P1' reactive site bond (where residues forming the reactive site have been identified as PnellipsisP1 and P1'ellipsisPn', where P1-P1' is the inhibitor scissile bond) has been identified at position Arg21-Ile22. The inhibitor disulphide bridges pattern has been determined as Cys5-Cys27, Cys18-Cys31, Cys42-Cys52 and Cys54-Cys57. The disulphide bridge arrangement observed in the RTI-III isoinhibitors is reminiscent of that found in a number of toxins (e.g. erabutoxin b). Moreover, the organization of the three disulphide bridges subset Cys5-Cys27, Cys18-Cys31 and Cys42-Cys52 is reminiscent of that found in epidermal growth factor domains. Preliminary 1H-NMR data indicates the presence of alphaalphaNOEs and 3JalphaNH coupling constants, typical of the beta-structure(s). These data suggest that the three-dimensional structure of the RTI-III isoinhibitors may be reminiscent of that of toxins and epidermal growth factor domains, consisting of three-finger shaped loops extending from the crossover region. Values of the apparent association equilibrium constant for RTI-III isoinhibitors binding to bovine beta-trypsin and bovine alpha-chymotrypsin are 3.3 x 109 m-1 and 2.4 x 106 m-1, respectively, at pH 8.0 and 21.0 degrees C. The serine proteinase : inhibitor complex formation is a pH-dependent entropy-driven process. RTI-III isoinhibitors do not show any similarity to other serine proteinase inhibitors except the low molecular mass white mustard trypsin isoinhibitor, isolated from Sinapis alba L. seed (MTI-2). Therefore, RTI-III and MTI-2 isoinhibitors could be members of a new class of plant serine proteinase inhibitors.

The length of a single turn controls the overall folding rate of "three-fingered" snake toxins

Snake curaremimetic toxins are short all-beta proteins, containing several disulfide bonds which largely contribute to their stability. The four disulfides present in snake toxins make a "disulfide beta-cross"-fold that was suggested to be a good protein folding template. Previous studies on the refolding of snake toxins (Ménez, A. et al. (1980) Biochemistry 19, 4166-4172) showed that this set of natural homologous proteins displays different rates of refolding. These studies suggested that the observed different rates could be correlated to the length of turn 2, one out of five turns present in the toxins structure and close to the "disulfide beta-cross". To demonstrate this hypothesis, we studied the refolding pathways and kinetics of two natural isotoxins, toxin alpha (Naja nigricollis) and erabutoxin b (Laticauda semifasciata), and two synthetic homologues, the alpha mutants, alpha60 and alpha62. These mutants were designed to probe the peculiar role of the turn 2 on the refolding process by deletion or insertion of one residue in the turn length that reproduced the natural heterogeneity at that locus. The refolding was studied by electrospray mass spectrometry (ESMS) time-course analysis. This analysis permitted both the identification and quantitation of the population of intermediates present during the process. All toxins were shown to share the same sequential scheme for disulfide bond formation despite large differences in their refolding rates. The results presented here demonstrate definitely that no residues except those forming turn 2 accounted for the observed differences in the refolding rate of toxins.

Leech antihemostatic proteins share the T-knot scaffold, a disulfide-reinforced structural motif

The occurrence of similar topologies among unrelated proteins is an emerging theme in structural biology. Here we report that the T-knot scaffold, a disulfide-reinforced structural motif shared by knottins and EGF-like proteins, is also present in leech antihemostatic proteins. Our finding emphasizes the versatile nature of this small structural motif, representing a compact structural unit suitable for the diverse biological functions performed by knottins, EGF-like proteins and leech antihemostatic proteins.

Effect of glutaredoxin and protein disulfide isomerase on the glutathione-dependent folding of ribonuclease A

Protein folding, associated with oxidation and isomerization of disulfide bonds, was studied using reduced and denatured RNase A (rd-RNase A) and mixed disulfide between glutathione and reduced RNase A derivative (GS-RNase A) as starting materials. Folding was initiated by addition of free glutathione (GSH + GSSG) and was monitored by electrospray mass spectrometry (ESMS) time-course analysis and recovery of the native catalytic activity. The ESMS analysis permitted both the identification and quantitation of the population of intermediates present during the refolding process. Refolding of rd-RNase A and GS-RNase A was also performed in the presence of glutaredoxin (Grx) and/or protein disulfide isomerase (PDI). All the analyses indicate a pathway of sequential reactions in the formation of native RNase A. First, the reduced protein reacts with a single glutathione molecule to form a mixed disulfide which then evolves to an intramolecular S-S bond via thiol-disulfide exchange. Only at this stage, the intermediate containing one intramolecular S-S reacts with a further glutathione molecule, reiterating the process. An analogous mechanism occurs in the refolding of GS-RNase A. The structural analysis of the intermediates formed during the refolding of RNase A showed for the first time that Grx is actually able to catalyze both formation and reduction of mixed disulfides involving glutatione. In both refolding processes, starting from either rd-RNase A or GS-RNase A, Grx displays a significant catalysis at the early stages of the process. Addition of PDI led to a net catalysis of the entire process without appearing to alter the refolding pathway. In the presence of both Grx and PDI, the two enzymes showed a synergistic activity either starting from rd-RNase A, as previously reported [Lundström, J., and Holmgren, A. (1995) J. Biol. Chem. 270, 7822-7828], or starting from GS-RNase A. Present data suggest that the synergistic effect can be explained assuming that Grx actually facilitates PDI action by catalyzing formation or reduction of mixed disulfides. The mixed disulfides are then rapidly converted into intramolecular disulfides in the presence of PDI. These steps are repeated sequentially throughout the whole refolding, resulting in an immediate formation of fully oxidized species even at the very beginning of the reaction. Finally, a Grx mutant, C14S Grx, in which one of the active site cysteine residues (Cys14) had been replaced by serine, had a similar effect on the distribution of folding intermediates, compared to the wild-type protein, thus demonstrating that Grx acts by a monothiol mechanism either in the reduction or in the oxidation step.

Ureteric pelvic stones

There is still controversy among urologists on the best treatment for ureteric pelvic stones. Recent advances in ureteroscopy with new methods of stone fragmentation (laser, electrohydraulic and ballistic lithotripsy) and current availability of small semirigid and flexible ureteroscopes have made this procedure rapid, easy and safe. Similarly, improvement in ESWL technology has also facilitated identification and treatment of stones above the iliac bone ring. In just over eight years (3/'88 - 6/'96) we treated 355 ureteral pelvic stones. The first approach was ESWL in 252 cases (by Dornier HM3 in 176, Dornier MPL 9000 in 42, Piezolith Wolf 2300 in 39 and EM plus Dormia basket in 15), ureteroscopy in 38 (by electrohydraulic) lithotripsy in 31, ultrasound lithotripsy in 5 and Lithoclast in 2) and litholapaxy by Dormia basket in 58. The overall stone-free rate was 75.5%, 95.3% and 84.5% respectively. The second line of treatment in unsuccessful cases was ULL or Dormia basket extraction and ESWL in 7 cases only. The overall success rate was 100%. Only 3 patients underwent open surgery (0.7%). There were 5 cases of ureteral perforation during ULL, which did not require surgical repair. No major complications occurred with either ESWL or Dormia basket procedures. We consider in-situ ultrasound-guided ESWL as first choice in managing ureteral pelvic stones, as the procedure is rapid, safe and technically simple. Ureteroscopy is a salvage procedure after ESWL failure. Endoscopic removal by Dormia basket is still a safe, effective procedure for small stones.

[Iatrogenic obstructive azoospermia]

Obstructive azoospermia is a common cause of sterility in men. In the past infection played an important role in the aetiology of obstructive azoospermia. Recently, however, the aetiology of obstructive azoospermia appears to be changing. So iatrogenic obstructive azoospermia has reached an important role in the field of obstructive azoospermia. In this work we show international literature about iatrogenic obstructive azoospermia. Unfortunately it is poor, in spite of an interesting item. We divided iatrogenic obstructive azoospermia into six groups, considering the possible anatomical site of obstruction. So we show the possible damages at the different levels: testis, epididymis, vas deferens, seminal vesicles, prostate and ejaculatory ducts.

[Orthotopic ileal neobladder of the Emikock type: technical points and functional results]

Ileal orthotopic neobladder represents, nowadays, the best urinary diversion after cystectomy. Emikock procedure was performed, in our institution, in 26 patients with bladder cancer T2-T4. At 6-60 months of follow-up 3 pts were died with local or at distance neoplastic recurrence, 2 were alive with neoplasms and 21 were NED. Nocturnal continence was good in 22 cases (88%) and only 3 patients were obstructed because of pseudodyssynergia in 2 and stricture in 1. Emikock neobladder even if needs a longer surgical time than other procedure and a long ileal tract is almost free from severe metabolic disorders. This technique offers a good protection of high urinary tract because of antireflux nipple and avoid the uretero-intestinal stricture. It not feasible, now, to know the functional trend of this reservoir on the long term. Adequate postoperative training is recommended to avoid the pseudodyssynergia and functional obstruction of reservoir.

Glutathione-dependent pathways of refolding of RNase T1 by oxidation and disulfide isomerization: catalysis by protein disulfide isomerase

Protein folding, associated with oxidation and isomerization of disulfide bonds, was studied using reduced and denatured RNase T1 (rd-RNase T1) and mixed disulfide between glutathione and reduced RNase T1 (GS-RNase T1) as starting materials. Folding was initiated by addition of free glutathione (GSH + GSSG) and was monitored by electrospray mass spectrometry (ES-MS) time-course analysis. This permitted both the identification and quantitation of the population of intermediates present during the refolding process. Refolding experiments were performed in the presence of different absolute concentrations of glutathione species while keeping the redox potential fixed, in order to evaluate the effect of the glutathione concentration on the distribution of the refolding intermediates. All the analyses indicate a pathway of sequential reactions in the formation of native RNase T1 which occurs via the reiteration of two steps: (i) formation of a species containing both mixed disulfides with glutathione and free protein thiols, and (ii) formation of an intramolecular disulfide via thiol-disulfide interchange reaction between them. Refolding of rd-RNase T1 and GS-RNase T1 was also performed in the presence of protein disulfide isomerase (PDI). Addition of PDI led to a catalysis of each individual reaction of the entire process without altering the refolding pathway. Refolding reactions carried out at different absolute concentrations of glutathione proved that GSH and/or GSSG participate directly in the reaction catalyzed by PDI. On the basis of these experiments and previous results on the refolding of RNase A [Torella, C., Ruoppolo, M., Marino, G., & Pucci, P. (1994) FEBS Lett. 352, 301-306], a hypothesis of a general pathway for folding of S--S containing proteins is proposed.

[pT1G3 bladder carcinoma: parameters of a correct therapy]

Between 13.8% and 27% of all superficial bladder cancers are represented by pT1G3 neoplasm. In the Department of Urology of Policlinico S. Marco-Zingonia, between February 1988 and June 1994, we treated 22 patients suffering for pT1G3 bladder tumor. TUR-B has demonstrated to be a good approach for treatment of superficial bladder cancer, with low morbility; on the opposite side, we have to underline the high rate of recurrence and of progression of the urothelium disease. Now a day our best approach for the treatment of pT1G3 bladder tumor is represented by radical cystectomy supplied by chemotherapy.

Identification of disulphide bonds in the refolding of bovine pancreatic RNase A

BACKGROUND

Comprehension of the rules that govern the folding process is still far from satisfactory, though it is nevertheless clear that all the information required to define the folding is encoded in the amino acid sequence. In proteins that contain disulphide bonds, folding is associated with disulphide bond formation. Protein species with different numbers of disulphides tend to accumulate during the process; these species can be trapped in a stable form, by quenching any remaining free SH groups, and then characterized in order to identify the disulphide bonds formed.

RESULTS

The refolding pathway of reduced and denatured RNase A has been studied using mass spectrometric strategies which allow identification of the formation and rearrangement of disulphide bonds during the process. When reoxidation was carried out in the presence of B M urea, producing the classic "scrambled' RNase, three native and 11 non-native disulphide bonds were identified. When the reoxidation was performed under nondenaturing conditions, the formation of several well defined non-native as well as native S-S bonds was observed at early stages of the refolding process. Under appropriate conditions, all four native disulphide bonds were identified at later stages of refolding and non-native disulphides were greatly diminished or non-existent. This stage corresponded with the almost complete recovery of biological activity of the protein.

CONCLUSIONS

The results presented here show that both native and non-native disulphide bonds are formed during the refolding of reduced and denatured RNase A in vitro under different experimental conditions. Essentially 14 disulphide bonds were observed of the 2B theoretically possible cysteine couplings. Although this number constitutes a significant fraction of the theoretical total, the occurrence of only a subset of disulphides clearly indicates that the formation of the S-S bridges does not occur at random, even when reoxidation takes place under denaturing conditions.

[External devices: for which patients?]

Vacuum therapy is a reversible, non-invasive form of treatment for partial impotence, with great success in USA. The story of vacuum therapy begins about 1960, when Osbon developed a vacuum tumescence device which he personally used for more than 20 years. The device was made commercially available many years ago and has been marketed under several names. The newer systems have incorporated a negative pressure pump to achieve vacuum. Osbon's system was patented in 1983, sale is permitted by the U.S. Food and Drug Administration, and it is available by prescription only. More than 10,000 units have been sold. There are four different types of vacuum therapy: 1) loading cone + constriction band; 2) external splint + negative pressure; 3) Negative pressure + constriction band; 4) Negative pressure + intracavernous injections, without the use of constriction band. Each basic system will be described. The authors make a comparison between the use of negative pressure devices plus tension band and the use of negative pression devices without tension band (plus C.I.D. with vaso-active agents). In the second case there's a sort of synergistic action between vaso-active agents and vacuum therapy, representing a sort of "vaso-active exercise" of the erectile tissue. There are no absolute contraindications to use of external penile devices and potential contraindications are few. The external penile devices described represent a reversible therapeutic modality that can augment an inadequate erection and they should prove useful in any man who needs erectile enhancement. These devices appear to be particularly effective in men with partial impotence in whom only erectile enhancement is needed.

Refolding by disulfide isomerization: the mixed disulfide between ribonuclease T1 and glutathione as a model refolding substrate

Protein folding, associated with isomerization of disulfide bonds, was studied using the mixed disulfide between glutathione and reduced ribonuclease T1 (GS-RNase T1) as a stable soluble and homogeneous starting material; conditions were selected to model those within the lumen of the endoplasmic reticulum where native disulfide bonds are formed in protein biosynthesis. Folding was initiated by addition of free glutathione (GSH +/- GSSG) to promote thiol-disulfide interchange and was monitored by intrinsic protein fluorescence, appearance of native ribonuclease activity, HPLC, and nonreducing SDS-PAGE. All the analyses indicated that native RNase T1 was recovered in high yield in a variety of redox conditions. Appearance of native activity followed first-order kinetics; kinetic analysis of the intrinsic fluorescence changes indicated an additional rapid process in some conditions, interpreted as the formation of a nonnative intermediate state. Analysis by HPLC and SDS-PAGE also indicated the formation of transient intermediates. In 1.5 M NaCl, GS-RNase T1 adopts a compact native-like conformation; refolding by thiol-disulfide interchange in these conditions was accelerated approximately 2-fold. Refolding of GS-RNase T1 was catalyzed by protein disulfide isomerase (PDI); substoichiometric quantities of PDI accelerated refolding several-fold. GS-RNase T1 refolding was inhibited by BiP; refolding was completely blocked in presence of a 5-fold molar excess of BiP, and the yield of refolding was substantially reduced by equimolar concentrations of BiP; the refolding was then restored by the addition of ATP. GS-RNase T1 is a convenient model substrate for studying protein folding linked to native disulfide formation in conditions comparable to those within the lumen of the endoplasmic reticulum.

[Radical prostatectomy: our experience]

Between July 1989 and June 1994 32 men (48-73 years old) underwent radical retropubic prostatectomy for prostate cancer. 26 patients (70%) presented with symptoms of bladder outflow obstruction. The primary tumour was understaged preoperatively in 5 patients (15.5%). At follow-up (6-66 months, average 24) significant urinary incontinence not occurred in our patients; sixty-two per cent reported a substantial problem with reduced or absent erection. A total of 23 patients was free of clinical or biochemical progression, observed in 28% of cases as distant or local progression. Radical prostatectomy is being performed with increasing frequency: trends in morbidity have been identified.

[Benign prostatic hypertrophy. Optimized diagnosis]

The optimal diagnostics of B.P.H. must be efficient, cheap and of spare invasiveness either physical than psychological. The optimization of diagnosis is the obtainment of high quality in the services provided, matched to a correct and shrewd utilisation of resources. To optimise a diagnosis efficiency is necessary, which means the largest degree of standardization of diagnostical procedures, with responsible management of economical factors. A course of standardization, cause his excessive simplification, cannot shared to a lot of Urologists, because in their opinion there is a risk to lose informations in every single patient, but is essential to use a universal language that make easy the comparison with patients and with results whether in order to clinics or trails. The standardisation of diagnostics consists to obtain the maximum of informations from present methodology and that is possible to realize in two way: improving the technique of execution and including the diagnostic test in the appropriate point of algorithm.

[TURP: what and when. Indications, results, complications: our experience]

Transurethral resection of the prostate (T.U.R.P.) has indeed replaced open surgery in the great majority of cases, particularly when the gland is estimated to weight 50-60 g or less. After prostatectomy the patient resumes a normal voiding pattern and obstructive symptoms quickly disappear, although irritative symptoms tend to persist for some time.

Analysis of RNase A refolding intermediates by electrospray/mass spectrometry

Electrospray/mass spectrometry (ES/MS) was extensively used to obtain information on disulphide-containing intermediates formed during refolding of bovine pancreatic ribonuclease A. The analysis showed the existence of an equilibrated population of disulphide bonded intermediates, and indicates that intermediates containing two intramolecular S-S are predominant until late stages of the refolding process. Mixed disulphides with exogenous glutathione were also detected, supporting previous evidence of conformational restrictions on the ability of RNase A to form intramolecular disulphides. The results indicate that ES/MS is a suitable technique to detect and characterize refolding intermediates.

[Penile nuclear magnetic resonance (NMR)]

Nuclear Magnetic Resonance (NMR) is a new diagnostic technique with great opportunities of application in the field of the penile pathologies. A new interest for this diagnostic technique was born when the use of vasoactive agents, like papaverine or PGE1, and the use of para-magnetic contrast agents, like gadolinium, were introduced. The introduction of dynamic NMR in andrology allowed a better definition of anatomical details and a better knowledge of penile micro-circulation. N.M.R. is showing a great diffusion, because of a little invasiveness (X-rays are not used in this technique). The Authors show a wide spread of possible applications of NMR in penile pathologies, helping in the interpretation of the images. In conclusion the authors describe NMR as a diagnostic technique with great possibilities of improvement, even if the high costs don't allow a better diffusion until now.

Protein-S-S-glutathione mixed disulfides as models of unfolded proteins

Mixed disulfides between glutathione and the reduced forms of disulfide-bonded proteins were generated and characterized to explore their suitability as models of the unfolded state of newly-synthesized secretory proteins. RNase T1 and alpha-lactalbumin were reduced and converted to mixed disulfide derivatives, named GS-RNase T1 and GS-alpha-lactalbumin, in good yield; the molecular masses of the derivatives were confirmed by electrospray mass spectrometry. The intrinsic fluorescence of the derivatives and the binding of the hydrophobic fluorescent dye ANS were characteristic of fully unfolded proteins. Fluorescence studies and enzyme activity data indicated that GS-RNase T1 could be refolded to a nativelike state at NaCl concentrations greater than 1.5 M, as was previously demonstrated for the reduced, carboxymethylated derivative of this protein. The [NaCl]-dependent folding/unfolding equilibrium for GS-RNase T1 was reversible and could be influenced by urea. Fluorescence studies indicated that GS-alpha-lactalbumin showed a [NaCl]-dependent partial shift toward a more nativelike state, which was enhanced by the presence of Ca2+ ions. Both of the GS derivatives stimulated the ATPase activity of BiP, with apparent affinities in the range 0.1-1.0 mM. The results indicate that these GS-S-protein mixed disulfide derivatives are ideal model unfolded proteins that can be used as substrates for detailed studies on secretory protein folding in vitro and on the interactions between unfolded proteins and facilitators of protein folding.

Trattamento Palliativo Del Carcinoma Prostatico con Ipertermia: Nostra Esperienza

Between August 1992 and June 1993, 6 high surgical risk patients affected by prostatic cancer with serious irritative symptoms underwent prostatic transrectal hyperthermia (one application of 60 minutes twice a week for 5 times). Transrectal hyperthermic treatment showed good results in subjective symptomatology with rated changes in urinary flow, but without any change in the progression of the disease. Best results may be obtained in association with radiotherapy or chemotherapy.

Terapia del carcinoma vescicale nella terza età

During the last year we have observed 57 patients aged over 70 years, affected by infiltrating bladder carcinoma. Cystectomy prevents haemorrhagic, septic and obstructive complications of the neoplastic bladder, with a better quality of life, but, except in the initial stages, is probably not able to heal the patient. Cystectomy is however the most effective therapeutic option and with an adequate preparation it is possible to operate elderly patients without serious complications.

TUIP: Un'alternativa nel trattamento dell'IPB

The authors report their experience with TUIP (Orandi's technique) in treating benign prostatic hypertrophy. Their good results lead to the conclusion that this method for removing obstruction in both young and elderly patients in precarious general conditions, is a valid alternative to traditional transurethral resection.

Derivazione ortotopica continente tipo emiKock: Nostra esperienza

Between May 1991 and October 1993, 16 male patients with bladder neoplasms underwent surgical hemiKock's technique of continent urinary reservoir: 7 patients were staged T1, 4 patients were T2, 3 patients were T3 and 2 patients were T4. 5 patients underwent neo-adjuvant M-VAC chemotherapy before surgery, 2 patients underwent radiotherapy and 2 patients underwent adjuvant chemotherapy after surgery. Demolition of the bladder, prostate and seminal vesicles was made by both an ascending and descending manoeuvre, and was sectioned just below the veru montanum to spare the external urinary sphincter. In 7 patients we followed Walsh's technique to spare neurovascular bundles. 60 to 62 cm of small intestine was selected for reservoir construction, stopping 20-30 cm before the ileo-cecal valve. Particular care was adopted for construction of the antireflux nipple valve; uretero-ileal anastomosis was made following Wallace's technique. Mean term of surgery was 6 hours. Sovrapubic cystostomy was removed after 8 days, and urethral catheter after 21 days. After a mean follow up of 3-30 months our results are the following: 2 patients deceased for a pelvic relapse and general metastasis. In one patient we had a neoplastic relapse just on the ileo-urethral anastomosis, so permanent catheterism was necessary.

[Urologic laparoscopy: preliminary experience]

Laparoscopy is a safe and reliable procedure for treatment of cryptorchid testicle, varix ligation, staging of lymph nodes in prostatic and in bladder cancer. Recently this procedure is adopted in management of renal cysts. From 2/92 to 7/92, we performed laparoscopic assessment in 31 patients: in 15 cases for varicocelectomy, in 9 for renal cysts, in 2 for lymph nodes dissection, in 3 for preoperatory evaluation, in 1 for unpalpable testicle and in 1 case for ileal perforation in orthotopic neobladder. In 1 case the procedure was unsuccessful because of damage of the spleen. All the patients were mobilized within 1 day postoperative treatment and discharged within 3 days. There are many present and potential application of laparoscopic surgery in urologic pathology, but we think that this technique must be carefully applied in order to avoid complications.

Disulfide isoform intermediates in the reoxidation of recombinant human basic fibroblast growth factor

The reoxidation of human recombinant basic fibroblast growth factor was investigated following treatment of the protein with a mixture of reduced and oxidized glutathione, both in the absence and in the presence of protein disulfide isomerase. The oxidative process took place throughout the formation of two transient intermediates and yielded a stable bFGF derivative, GS2-bFGF. All of these components were separated by HPLC and accurately characterized at the molecular level by advanced mass spectrometric procedures. When the reoxidation was carried out in the presence of PDI, a 4-fold increase in the reaction rate was estimated. A mixed disulfide with a single glutathione molecule was shown to occur in the two transient intermediates, each of which has different cysteine residues involved in the linkage. The final product GS2-bFGF was structurally different from other bFGF derivatives previously described [Thompson, S. A. (1992) J. Biol. Chem. 267, 2269-2273; Caccia et al. (1992) Eur. J. Biochem. 204, 649-655]. The four cysteine residues are all involved in disulfide bridges; Cys 34 and Cys 78 are linked to exogenous glutathione, whereas Cys 91 and Cys 101 form an intramolecular S-S bridge.

Structural characterization of a biologically active human lipocortin 1 expressed in Escherichia coli

Lipocortin or annexin 1 is a calcium-dependent phospholipid-binding protein which probably acts as a glucocorticoid- regulated anti-inflammatory factor. cDNA for human lipocortin 1 was cloned in the pT7.7 expression plasmid under the control of the inducible bacteriophage T7 RNA polymerase promoter. Upon induction with isopropyl thio-beta-D-galactoside, large amounts of the protein were produced and accumulated in Escherichia coli in a soluble form. The recombinant protein was purified to homogeneity by means of two subsequent ion-exchange chromatographic steps. The final yield was about 30 mg/l bacterial culture. Electrospray mass spectrometric analysis of the purified protein demonstrated that the recombinant product corresponds to the native human lipocortin 1, without the initial methionine and with a free N-terminal alanine; tryptic peptide mapping by fast-atom-bombardment mass spectrometry showed that the recombinant protein contains cysteine residues at positions 263 and 324 with free thiol groups, whereas Cys270 and Cys343 are probably involved in an intrachain disulfide bridge. Recombinant human lipocortin 1 reduces the carrageenin-induced paw oedema in rat in vivo and inhibits porcine pancreatic phospholipase A2 activity in vitro; in both cases, a dose-related response is observed.