Primary malignant melanoma of the bladder

Primary malignant melanomma of bladder is extremely rare: 18 cases are reported to date. An 82 year-old man underwent trans-urethral resection of bladder for a bleeding tumor of the posterior wall. Histological diagnosis was melanoma of the bladder. There was no history of previous or regressed cutaneous malignant melanoma. Margins of the bladder lesion contained atypical melanocytes similar to those commonly seen in the periphery of primary mucous membrane lesions. Clinical studies and radiological examinations were negative for other primary site of melanoma. The patient had a bladder recurrence that was consistent with primary tumor and died of widespread disease 9 months after diagnosis.     

Chemical and enzymatic treatment of endothelin

Endothelin-1 (ET), the most potent vasoconstrictor yet discovered, is a peptide containirig 21 amino acids with two intrachain disulfide bridges. With the aim of obtaining two-chain derivatives, Et was submitted to chemical and enzymatic treatments. Reaction of ET with CNBr in 70% HCOOH gave, in addition to the expected [Hse⁷ lactone]-7,8-seco-ET and unreacted material, a by-product whose molecular weight was 25 m.u. greater than that of ET. When the reaction mixture, after lyophilisation, was immediately quenched with NH3-saturated dry MeOH, two products could be recovered in a 5:1 ratio, both obtained by nucleophilic attack of the homoserine lactone: the expected [Hse⁷-NH₂]-7,8-seco-ET and [Hse⁷]ET, resulting from competitive intramolecular reaction of the deprotonated α-amino group of the Asp⁸ residue. The Lys⁹-Glu¹⁰ bond turned out to be very resistant to enzymatic attack both by Lys-C-endopeptidase and trypsin. The 9,10-seco-ET derivative could be obtained by treatment with Lys-C-endopeptidase only by using a high enzyme/ET ratio and after a prolonged incubation time. Cleavage of the Lys⁹-Glu¹⁰ bond could not be achieved by treatment with trypsin, even with a high enzyme/substrate ratio. The main product was 13, 14-seco-ET, deriving from the action of chymotripsin (present as an impurity in the trypsin preparation) on Tyr¹³. The structure of these peptides was confirmed by amino-acid sequence analysis and fast atom bombardment mass spectrometry (FAB-MS). Nicking of the ET structure at different positions had different impact on the biological properties of the resulting derivatives. © Munksgaard 1995.     

p53 OVEREXPRESSION AND HUMAN PAPILLOMAVIRUS INFECTION IN TRANSITIONAL CELL CARCINOMA OF THE URINARY BLADDER: CORRELATION WITH HISTOLOGICAL PARAMETERS

Seventy-nine transitional cell carcinomas (TCCs) of the urinary bladder (25 grade 1, 22 grade 2, and 32 grade 3 tumours) were examined for p53 overexpression by immunohistochemistry with a monoclonal antibody and for human papillomavirus (HPV) infection by the polymerase chain reaction (PCR). Positive immunostaining for p53 was detected in 40·5 per cent of the cases; the percentage of positive cases was significantly lower in low-grade (G1 and G2) TCCs than in high-grade (G3) tumours (10·6 per cent vs. 84·4 per cent; P <0·0001). The overall rate of HPV infection was 32·9 per cent; 20·3 per cent of the cases were positive for HPV 16, 3·8 per cent for HPV 18, and 8·9 per cent for both. Consensus primers as well as type-specific primers for HPV types 6, 11, and 33 failed to detect any additional case with HPV infection. The prevalence of HPV 16 and/or HPV 18 infection was significantly higher in low-grade than in high-grade tumours (44·7 per cent vs. 15·6 per cent; P =0·0061). p53-positive cases were more common among papillary, deeply infiltrating tumours, and HPV-positive cases among papillary, non-infiltrating lesions. According to these data, p53 overexpression and HPV 16/18 infection are common findings in bladder TCC and there appears to be an inverse correlation of p53 overexpression and of HPV infection with tumour aggressiveness. The possibility of different molecular pathways in superficial low-grade and in invasive high-grade tumours is suggested.     

Duplex-Doppler assessment of cirrhosis in patients with chronic compensated liver disease

Portal venous flow velocity (PFV) was measured with duplex-Doppler equipment in 50 normal subjects and in 117 patients with suspected chronic liver disease who showed no evidence of decompensation such as ascites, hepatic encephalopathy, jaundice or oesophageal bleeding. All the patients underwent percutaneous liver biopsy which demonstrated non-cirrhotic liver disease in 58 cases (CH-patients: steatosis 8, persistent chronic hepatitis 8, active chronic hepatitis 42) and liver cirrhosis in the other 59 cases (LC-patients). The normal subjects and the CH-patients had similar values of max-PFV and mean-PFV (max-PFV 26.7±3.2 and 25.7±3.4 cm/s respectively; mean-PFV 22.9±2.8 and 22.4±3.8 cm/s respectively). The LC-patients’ values (max-PFV 19.3±3.5; mean-PFV 16.9±2.9) were significantly lower than those of the normal subjects (P<0.001) and of the CH-patients (P<0.001). Considering the normal max-PFV to be in the range 20–33.1 cm/s (mean±2 s.d. of the normal subjects, 95% confidence limits), max-PFV was reduced in 0/50 normal subjects, 1/58 CH-patients and 39/59 LC-patients (66.1% sensitivity; 98.2% specificity). In conclusion, the duplex-Doppler measurement of PFV is of great interest in the diagnostic study of patients with suspected chronic compensated liver disease and in the early diagnosis of cirrhosis. A low max-PFV is a reliable pointer to liver cirrhosis, whereas a normal max-PFV indicates a non-cirrhotic liver disease but is less probative. Each centre should standardize normal PFV values in order to establish their own threshold value for diagnosing liver cirrhosis.     

Affinity enhancement of complementary peptide recognition

A peptide hydropathically complementary to Big Endothelin [Big ET] residues 16-29 has been synthesized in a multimeric form starting from an octadentate poiylysine core, essentially in a way similar to the procedure used for the production of multiple antigenic peptides [MAP's], Interaction between the multimeric complementary peptide [8δET] and the Big ET fragment 16-32 containing the target complementary region, also synthesized in a multimeric form [8ET], was evaluated by analytical high performance affinity chromatography and solid phase binding assays. While the binding interaction between the monomerics peptide pair was in the micromolar range, the recognition between the corresponding multimeric form was characterized by enhanced binding affinity of at least two orders of magnitude. In solution, complex formation between multimeric complementary peptide and target Big ET sequence in the monomeric and multimeric form was accompanied by precipitation at concentrations higher than 0.5 mg/mL and 0.1 mg/mL, respectively. Polyclonal antibodies raised against the multimeric target sequence recognized multimeric and monomeric ET target sequences with binding affinities similar to binding affinities exhibited by the multimeric complementary peptide. Multimerization of hydropathically complementary peptides could provide an improved opportunity to measure and thus probe quantitative binding properties of complementary peptides.     

An Implantable Intracardiac Accelerometer for Monitoring Myocardial Contractility

As the myocardium contracts isometrically, it generates vibrations that are transmitted throughout the heart. These vibrations can be measured with an implantable microaccelerometer located inside the tip of an otherwise conventional unipolar pacing lead. These vibrations are, in their audible component, responsible for the first heart sound. The aim of this study was to evaluate, in man, the clinical feasibility and reliability of intracavity sampling of Peak Endocardial Acceleration (PEA) of the first heart sound vibrations using an implantable tip mounted accelerometer. We used a unidirectional accelerometer located inside the stimulating tip of a standard unipolar pacing lead: the sensor has a frequency response of DC to 1 kHz and a sensitivity of 5 mV/G (G - 9.81 m/s^?2). The lead was connected to an external signal amplifier with a frequency range of 0.05–1,000 Hz and to a peak-to-peak detector synchronized with the endocardial R wave scanning the isovolumetric contraction phase. Following standard electro-physiological studies, sensor equipped leads were temporarily inserted in the RV of 15 patients (68 ± 15 years), with normal regional and global ventricular function, to record PEA at rest, during AAI pacing, during VVI pacing, and during dobutamine infusion (up to 20 |mg/kg per min). PEA at baseline was 1.1 G ± 0.5 (heart rate = 75 ± 14 beats/rain) and increased to 1.3 G ± 0.9 (P = NS vs baseline) during AAI pacing (heart rate = 140 beats/min) and to 1.4 G ± 0.5 (P = NS vs baseline) during VVI pacing (heart rate = 140 beats/min). Dobutamine infusion increased PEA to 3.7 G ± 1.1 (P < 0.001 vs baseline), with a heart rate of 121 ± 13 beats/min. In a subset of three patients, simultaneous hemodynamic RV monitoring was performed to obtain RV dP/dt_max, whose changes during dobutamine and pacing were linearly related to changes in PEA (r = 0.9; P < 0.001). In conclusion, the PEA recording can be consistently and safely obtained with an implantable device. Pharmacological inotropic stimulation, but not pacing induced chronotropic stimulation, increases PEA amplitude, in keeping with experimental studies, suggesting that PEA is an index ofmyocardial contractility. Acute variations in PEA are closely paralleled by changes in R V dP/dt_max, but are mainly determined by LV events. The clinical applicability of the method using RV endocardial leads and an implantable device offers potential for diagnostic applications in the long-term monitoring of myocardial function in man.     

Allogeneic bone marrow transplantation versus chemotherapy in high-risk childhood acute lymphoblastic leukaemia in first remission

We compared the outcome of children with high-risk acute lymphoblastic leukaemia (HR-ALL) in first complete remission (first CR) treated with chemotherapy (CHEMO) or with allogeneic bone marrow transplantation (BMT) in a multicentre study.   All children treated by the Italian Paediatric Haematology Oncology Association for HR-ALL in first CR between 1986 and 1994 were eligible for the study. 30 children were given BMT at a median of 4 months from first CR, with preparative regimens including total-body irradiation ( n  =25/30). 130 matched controls for BMT patients were identified among 397 HR-ALL CHEMO patients. Matching on main prognostic factors and duration of first CR was adopted to control the selection and time-to-transplant biases. The comparative analysis was based on the results of a stratified Cox model. The estimated hazard ratios of BMT versus CHEMO at 6 months, 1 year and 2 years after CR were 1.38 (CI 0.59–3.24), 0.69 (CI 0.27–1.77) and 0.35 (CI 0.06–1{\raise 5mu ..91), with an overall non-significant difference between the two groups ( P  = 0.34). With a median follow-up of 4 years, the disease-free survival was 58.5% (SE 9.3) in the BMT group and 47.7% (SE 4.8) in the CHEMO group, at 4 years from CR. Non-leukaemic death occurred in 4% of CHEMO and 10% of BMT patients. In the BMT group the estimated cumulative incidence of relapse at 1.5 years from CR was 31.5% (SE 8.8) and did not change thereafter, whereas in the CHEMO group the corresponding figure was 29.2% (SE 4.1) and the incidence continued to increase thereafter (48.2% (SE 4.8) at 4 years from CR).   The results of this study suggest that, with respect to the CHEMO group, the higher risk of early failure in the BMT group is outweighed by the lower risk of relapse after 1 year. Results prompt the need for a prospective study, in order to demonstrate the likely advantage of BMT in HR childhood ALL in first CR.     

In vitro interactions of opioid peptides with phospholipids

The interaction of leu-enkephalin with phosphatidylserine has been studied with ultraviolet and circular dichroism spectroscopy methods as well as with fluorescence anisotropy techniques. The data reported hereunder confirm the existence of binding between the two species, and also support the hypothesis that not only the tyrosine, but also the phenylalanine residue in the leu-enkephalin molecule is involved in peptide-lipid interaction. In addition, ultraviolet and CD evidence, taken together, tend to suggest that both aromatic residues are bound, with a different degree of involvement, to the same region of the lipid molecule. The data reported are discussed in terms of the interaction model previously proposed by us.     

The intraventricular conduction time of fetal heart in pregnancies with suspected fetal growth retardation

Summary. Electrocardiographs from 68 fetuses with ultrasound evidence of growth retardation were recorded from the maternal abdomen; QRS duration was measured and compared to normal standards previously obtained in our Institute. Of these fetuses, 54 were small-for-gestational-age at birth and 44 exhibited QRS duration values below -2SD for their gestational age. All but one of the 14 normal fetuses showed normal QRS values (positive predictive value = 98%; negative predictive value = 57%). Of 11 fetuses with QRS duration values below -4SD, nine were particularly small, below the 2nd centile of weight for gestation. QRS duration measurements may represent a sensitive method for identifying fetal growth-retardation. The QRS duration also seems to provide a reliable prognosis of perinatal outcome. Normal values are a reassuring factor: abnormal cardiotocographic records were observed in only 2 out of 23 cases and no low Apgar scores or perinatal deaths occurred. QRS values below -4 SD proved to be associated with abnormal cardiotocographic records (7/13), low Apgar scores (5/15) and perinatal deaths (3/15).     

Effect of mesalazine on mucosal immune biomarkers in irritable bowel syndrome: a randomized controlled proof-of-concept study

Background  Intestinal immune infiltration contributes to symptoms in patients with irritable bowel syndrome (IBS).
Aim  To assesses the effect of mesalazine (mesalamine) on mucosal immune cells in patients with IBS, through a pilot study.
Methods  A randomized, double-blind, placebo-controlled trial in 20 patients with IBS in tertiary care setting. Patients were randomized to receive placebo or 800 mg mesalazine three times daily for 8 weeks. The primary endpoint was a significant reduction in total colonic immune cells on biopsies obtained at the end of treatment compared to baseline. Secondary endpoints included effects on subsets of immune cells, inflammatory mediators and symptom severity. Intention-to-treat analysis was performed.
Results  Mesalazine markedly reduced immune cells as compared with placebo ( P  = 0.0082); this effect was ascribed to a marked inhibition of mast cells ( P  = 0.0014). Mesalazine significantly increased general well-being ( P  = 0.038), but had no significant effects on abdominal pain ( P  = 0.084), bloating ( P  = 0.177) or bowel habits. No serious drug-related adverse events were reported during the study.
Conclusions  Mesalazine is an effective and safe approach to reduce mast cell infiltration and may improve general well-being in patients with IBS. These results support the hypothesis that immune mechanisms represent potential therapeutic targets in IBS.