Differential effects of injections of anti-mu and anti-delta monoclonal antibodies on B-cell populations in adult mice: regulation of xenoreactive natural antibody-producing cells

BACKGROUND: The depletion of differential B cell and xenoreactive natural antibodies (XNA) by anti-delta and anti-mu injections was analyzed in adult mice. Sequential treatment with anti-delta and then anti-mu induces a complete depletion of B cells and XNA and represents a potential approach to induce xenograft tolerance. METHODS: Adult mice were injected with anti-mu, anti-delta, anti-delta then anti-mu, or control isotype monoclonal antibodies from day 0 to day 14. The different B-cell populations were analyzed by FACS and immunohistology. Ig production was tested by ELISA. XNA were analyzed by FACS. RESULTS: Anti-mu injections induced a depletion of IgMhigh, immature B cells, marginal zone B cells, and B1 cells and an increase of IgG-XNA production. Anti-delta injections induced mature conventional IgDhigh B-cell depletion and increased IgM-XNA production. Interestingly, sequential injections of anti-delta then anti-mu induced a depletion of immature B cells, mature B cells (MZ, B2, and B1), and XNA. CONCLUSIONS: These results demonstrate that mature B-cell depletion in adult mice can be obtained by mAb injections and depends on the surface immunoglobulin cross-linking threshold. Indeed, anti-mu mAb depleted IgMhigh B cells (MZ and B1) and anti-delta, IgDhigh B cells (B2). The differential B-cell suppression shows that conventional B cells are responsible in the IgG-XNA production and MZ and B1 cells in the IgM-XNA production. Sequential repeated injections of anti-delta then anti-mu mAb depleted all B-cell populations and suppressed the whole XNA production.     

Kidney and urinary tract injuries. Experience with 113 cases

BACKGROUND: Trauma of the kidney and urinary tract is not rare in emergency surgery and the related treatment needs today high competence and interdisciplinary approach. Aim of the study was to analyze the personal experience in order to find differences in the treatment during the last years especially for trauma of the kidney. METHODS: The authors report 113 cases of kidney or urinary tract trauma out of 16,569 patients admitted in emergency between 1981 and 1995. Fifty patients (44%) underwent surgery. Thirty patients (26%) underwent surgery for kidney trauma but in only 5 (16%) conservative surgery for partial damage was possible. Section of the ureter occurred in one patient. Ten patients had a rupture of the bladder and 9 the rupture of urethra. The cause of trauma was a gunshot wound in 11 patients (22%). Nineteen patients (38%) had also damage to other organs. RESULTS: The results show absence of morbidity or mortality related with urinary tract trauma. CONCLUSIONS: The analysis of these cases shows that the improvement of diagnostic possibilities allowed the reduction of surgical interventions especially for kidney trauma.     

Latex allergy. An not rare intraoperative event

Latex allergy has become a real problem among both surgical staff (paramedics and physicians) and patients especially pediatric patients with urogenital malformations and spina bifida. Latex allergy is produced from both natural molecules which compose the substance produced from Hevea brasiliensis (rubber tree) and industrial additives contents in latex devices. Diagnosis of latex allergy may be carried out through a preoperative Prik-test. A characteristic of latex allergy reaction is the starting of symptoms (more than 15 minutes after allergen contact). Pathophysiology of latex allergy is the same of all allergic reactions; it is an antigen-antibody reaction and type I or II reaction may occur. There are a lot of devices that surgeons and anesthesists use in the operative theatre and that should not be used in presence of a patient with latex allergy. Guaranteed latex-free devices should always be present in store.     

Target controlled infusion (TCI): applications of the "TCI visual" program in anesthesia and sedation with propofol

BACKGROUND: Systems for Target Controlled Infusion accepting not only patient' data, like Diprifusor, but also a pharmacokinetic model have not been available in Italy in the last years. Therefore a program which controls a Pilot Anesthesia Vial pump and accepts any pharmacokinetic model was developed and applied to propofol infusion for anaesthesia and sedation. METHODS: Two versions of the Visual TCI program have been developed. The first, at intervals, supplies the anaesthetist with the values for the pump; the second directly interacts with the pump. The program also supplies the anaesthetist with the current amount of drug in each compartment and with the estimated awakening time. DESIGN: preliminary prospective study. SETTING: operatory theatre and Intensive Care Unit in a University Hospital. Patients: 6 patients undergoing total intravenous anaesthesia with propofol and fentanyl for abdominal surgery; 6 patients undergoing sedation with propofol in an Intensive Care Unit (the first 4-hour period was taken into account). Interventions: propofol infusion was regulated by the Visual TCI program. The first version was employed in three patients of each group and the second one in the others. Hypo- and hypertensive episodes (systolic pressure less than 80 mmHg or higher than basal value plus 25%) were recorded during anaesthesia and sedation. Propofol concentration was measured in plasma three times at defined intervals and per cent differences between measured and computer-calculated values (Predictive error, PE) were calculated. RESULTS: No hypo- or hypertensive episodes were recorded. PE was 27.4 +/- 17.9%. CONCLUSIONS: The program was easily employed, caused no inconvenience, and its use was associated with a remarkable cardiovascular stability. PE distribution was acceptable on the ground of the criteria reported in the literature. The program can be applied to drugs other than propofol, with both two and three compartment pharmacokinetic models and the anaesthetist can choose the most suitable model for the patient.     

Mortality among workers in the geothermal power plants at Larderello, Italy

BACKGROUND: Since the early 1990s various European electricity companies have set up a research program, named EURELEX, devoted to the development of a comprehensive and validated title-occupation--job-exposure matrix (i.e., an instrument to assess exposures from occupations and jobs), in order to estimate and quantify past exposure to a number of potentially carcinogenic agents plus a few selected other toxic substances. The EURELEX program was first applied in Italy to a cohort of geothermal workers in Larderello, Tuscany. METHODS: The cohort mortality study comprised 4,237 men who had worked at the geothermal power plant between 1950 and 1990. Vital status and death certificates were obtained from registration offices in the municipality of birth or death. Particular attention was paid to neoplastic effects of exposure to asbestos, largely used in the past for pipeline insulating purposes. The matrix allowed the workers to be subdivided into several categories according to estimated absestos exposure. Smoking information was not available. RESULTS: No excess mortality was found for all causes and total cancer mortality. A small excess of pleural cancer (2 obs. vs. 1.4 exp.) was not statistically significant. The effect of other agents included in the matrix was also examined: the small excess of leukemia among those exposed to solvents prior to 1963 (year of benzene ban in Italy) did not reach the level of statistical significance. No cases of leukemia were found among the workers presumed to have been exposed to important ELF electromagnetic fields. CONCLUSION: The study provides reassuring information on a large cohort of a unique geothermal power plant since no significant excess mortality for asbestos related cancers was observed. Furthermore, it represents a useful application and validation of a comprehensive job-exposure matrix for the electric industry in Europe.     

A phase I and pharmacokinetic trial of terephthalamidine (NSC 57155) as a 120-hour continuous infusion

In this phase I study, terephthalamidine was administered as a 120-hour continuous infusion repeated every 21 days. Thirteen patients received 27 courses of terephthalamidine at four dose levels (14, 28, 46, and 70 mg/m²/day). Dose-limiting toxicity consisted of profound and intractable anorexia, weight loss and prostration in all patients. Toxicity was delayed and accompanied by hyponatremia and hypokalemia. No hematologic or other toxicity was documented. One patient with adenocarcinoma of the lung had a 40% decrease in mediastinal lymph nodes and resolution of a pleural effusion lasting 2 months. Pharmacokinetic analysis by HPLC was performed in all patients during their first course. The harmonic mean terminal half-life for terephthalamidine was 23 hours with a plasma clearance of 1.7 l/hr/m². Both plasma concentrations achieved during infusion (r² = 0.9) and area under the curve (AUC) (r² = 0.8) were proportional to increase in dose (p < 0.002). Renal excretion accounted for 64% of the total cumulative dose, with an average renal clearance of 1.16 l/hr/m². Due to the unacceptable toxicity seen at all doses with this schedule, no further studies are recommended unless the mechanism of toxicity is better understood and can be prevented.     

Variability of Clinical and Pressure-Flow Study Variables After 6 Months of Watchful Waiting in Patients with Lower Urinary Tract Symptoms and Benign Prostatic Enlargement

Purpose

We quantified the physiological variability of clinical and pressure-flow study variables in patients with symptomatic benign prostatic enlargement.

Materials and Methods

Symptom scores were measured, and advanced urodynamic studies with pressure-flow analysis were performed in 178 patients before and 6 months after a period of watchful waiting.

Results

Patients without bladder outlet obstruction experienced significant symptomatic improvement. Symptoms in patients with obvious bladder outlet obstruction did not improve significantly. The reproducibility of mean pressure-flow variables was evident. However, there was an important intra-individual variability. Patients with obvious bladder outlet obstruction showed a significant decrease in detrusor pressure at maximal flow of 14 cm. water, a significant decrease in the urethral resistance factor of 7 cm. water and a significant decrease of 1 obstruction class on the linear passive urethral resistance relation nomogram, indicating less severe bladder outlet obstruction.

Conclusions

Mean differences among therapy groups must be regarded critically, especially when the differences are slight and possibly within physiological variability.