Biomedical subjects

L Barbieri

Publications and source records attributed to L Barbieri.

At least 37 records · Page 2Linked to original sources

PubMed1993

Four-drug intracavernous therapy for impotence due to corporeal veno-occlusive dysfunction.

Although veno-occlusive dysfunction is a frequent cause of impotence, a definitive therapeutic strategy has not yet been clearly defined. A total of 56 patients with corporeal veno-occlusive dysfunction diagnosed by dynamic infusion cavernosometry-cavernosography (flow to maintain erection greater than 10 ml. per minute and rate of corporeal pressure decrease after interruption of intracavernous infusion greater than 50 mm. Hg for 30 seconds) not considered suitable candidates for surgery underwent self-injection therapy. A vasoactive mixture composed of 12.1 mg./ml. papaverine hydrochloride, 10.1 micrograms./ml. prostaglandin E1, 1.01 mg./ml. phentolamine mesylate and 0.15 mg./ml. atropine sulfate was used. After dose titration of the drug mixture 54 patients (95%) were able to obtain sustained rigid erections that guaranteed satisfactory sexual activity. Mean (plus or minus standard error of mean) volume of injected mixture was 0.42 +/- 0.09 ml. (range 0.25 to 0.90 ml.). Four patients (7%) reported transient hypotension that did not recur after the application of a penile rubber band before injection. At a mean followup of 16 months 6 patients (11%) discontinued use of injections, 37 (69%) were satisfied and using the mixture, and 11 (20%) maintained rigid erections using a lower than initial dose. No major complications were encountered. The association of drugs with different mechanisms of action caused a synergism that potentiated the therapeutic activity and reduced side effects by decreasing the total drug dose.

Alprostadil↗

PubMed1993

Effects of ribosome-inactivating proteins on Escherichia coli and Agrobacterium tumefaciens translation systems.

The effects of 30 type 1 and of 2 (ricin and volkensin) type 2 ribosome-inactivating proteins (RIPs) on Escherichia coli and Agrobacterium tumefaciens cell-free translation systems were compared with the effects on a rabbit reticulocyte translation system. The depurinating activity of RIPs on E. coli ribosomes was also evaluated. Only six type 1 RIPs inhibited endogenous mRNA-directed translational activity of E. coli lysates, with submicromolar 50% inhibitory concentrations. Four RIPs had similar activities on poly(U)-directed phenylalanine polymerization by E. coli ribosomes, and three RIPs inhibited poly(U)-directed polyphenylalanine synthesis by A. tumefaciens ribosomes, with submicromolar 50% inhibitory concentrations.

Agrobacterium tumefaciens↗

PubMed1993

Long-term clinical reliability of transurethral and open prostatectomy for benign prostatic obstruction: a term of comparison for nonsurgical procedures.

To elucidate the long-term reliability of prostatectomy, we evaluated 92 benign prostatic hyperplasia patients who had been submitted to either transurethral or open surgery at the 5-year follow-up. Ninety-five percent of the patients were still nonobstructed and subjectively satisfied of their urinary status. Postoperative mortality was presumably not related to the previous operation. Until now, nonsurgical procedures did not guarantee the results achieved by surgical treatment and should thus be reserved for patients at high operative risk or refusing surgery.

Follow-Up Studies↗

PubMed1993

Velocity and flow volume gradients along the cavernosal artery: a duplex and color Doppler sonography study.

Duplex and color Doppler sonography were used to assess 130 impotent patients and 8 potent controls. Cavernosal artery diameter, peak flow velocity and volume flow rate were evaluated at the level of the crura of the corpora cavernosa and 1 cm proximal to the corona penis. Potent controls and nonarteriogenic impotent patients showed a 20% reduction in hemodynamic parameters at the periphery of the cavernosal arterial tree. In patients with occlusive disease, involving either the upper arterial tree or the entire course of the cavernosal artery, the gradient was maintained. In patients with selective occlusive disease of the distal segment of the cavernosal artery the hemodynamic gradient almost doubled. Hemodynamic gradients can be identified along the cavernosal artery and provide additional information to arteriographic data for the selection of candidates for penile vascular reconstructive surgery.

Arterial Occlusive Diseases↗

PubMed1993

Morphodynamic assessment of penile circulation in impotent patients: the role of duplex and color Doppler sonography.

Duplex and color Doppler sonography were used to assess the vascular status of 240 impotent patients. The tests were performed before and after intracorporal injection of a standard dose of a vasoactive mixture and measurements were done both at the crura and at the midshaft of the penis. Particular care was taken in the evaluation of cavernosal arteries diameter, wall pulsatility, morphology of spectral waveform, blood flow acceleration, systolic and diastolic flow velocity and flow volume. Resistance and pulsatility indexes of the cavernosal arteries were also measured. Flow along the deep dorsal vein was quantified when possible. Cavernosal artery peak systolic flow velocity, flow volume and acceleration were the best indicators of arterial penile circulation. Persistently elevated (> 10 cm/s) diastolic flow in the cavernosal arteries positively correlated with a diagnosis of venogenic impotence obtained by dynamic infusion cavernosometry--cavernosography in almost 80% of cases. Duplex and color Doppler sonography permit to thoroughly evaluate cavernosal arteries function and seem to have a promising role in the study of the veno-occlusive mechanism of the corpora cavernosa.

Blood Flow Velocity↗

PubMed1993

[Coronary stenting: indications and results].

Intracoronary stenting has been introduced to overcome the 2 main limitations of balloon angioplasty:acute vessel closure and late restenosis. Palmaz-Schatz stent is today the most diffuse prosthesis; the incidence of subacute occlusion and of restenosis reported by various Authors are acceptable. The risk of major complications however is definite and anticoagulation mandatory. Only controlled clinical studies and improvements in the stent design and in the knowledge of thrombotic processes will permit an enlargement of stent indications.

Arterial Occlusive Diseases↗

PubMed1993

A new 'solid phase' procedure to synthesize immunotoxins (antibody-ribosome inactivating protein conjugates).

A method to produce immunotoxins (conjugates comprising of a monoclonal antibody and toxin) using ribosome inactivating protein anchored on an affinity gel derivatized with triazinic dye is described. The adsorbed toxins were activated with 2-imino-thiolane and then conjugated to monoclonal antibody activated by SPDP. The "heterogeneous phase" system offered several advantages, reducing the usually required purification steps and opening a way to automatize the conjugation procedure.

Antibodies, Monoclonal↗

PubMed1993

[Doppler color echography in the diagnosis of impotence].

This study reports the experience achieved with duplex and color Doppler ultrasonography in 120 impotent patients. The following morphodynamic parameters of the cavernosal arteries were studies before and after intracorporal injection of a mixture of vasoactive drugs: arterial diameter, wall pulsatility, morphology of the spectral waveform, peak systolic velocity, end diastolic velocity and flow volume. The veno-occlusive mechanism of the corpora cavernosa was studied directly by determination of flow along the deep dorsal vein of the penis and indirectly by serial evaluation of the diastolic flow of the cavernous arteries.

Adult↗

PubMed1992

Immunological properties of ribosome-inactivating proteins and a saporin immunotoxin.

Antibodies have been raised in rabbits against plant ribosome-inactivating proteins (RIPs) and used to demonstrate cross-reactivity between RIPs from plants belonging to the same family, but little or no cross-reactivity between RIPs from taxonomically unrelated plants. When an immunotoxin consisting of saporin conjugated to bovine IgG was injected into rabbits, the animals formed antibodies against both saporin and bovine IgG.

Animals↗

PubMed1992

Some ribosome-inactivating proteins depurinate ribosomal RNA at multiple sites.

Saporin-S6, a ribosome-inactivating protein (RIP) from Saponaria officinalis released more than 1 mol of adenine/mol of ribosomes from house fly (Musca domestica) larvae and from rat liver. The release of adenine from rat liver ribosomes by several RIPs (plant enzymes with RNA N-glycosidase activity) was examined. Saporins, pokeweed antiviral protein from roots of Phytolacca americana (PAP-R), and trichokirin from Trichosanthes kirilowii seeds depurinated rat liver ribosomes at more than one site. Up to 33 mol of adenine were released from 1 mol of ribosomes. This property is not common to all RIPS.

Animals↗

PubMed1992

Inhibition of protein synthesis in liver and kidney of mice by bolesatine: mechanistic approaches to the mode of action at the molecular level.

Protein synthesis was assayed in liver and kidney of mice treated with bolesatine, a toxic glycoprotein from the mushroom Boletus satanas (Lenz) which was previously shown to be an inhibitor of protein synthesis by cell-free systems in vitro and by cultured cell-lines. Protein synthesis in vivo (Swiss mice) is inhibited in a dose-dependent manner in liver and kidney. The mechanism of action does not appear to be due to RNA-N-glycosidase activity of bolesatine or a RNAase activity of this toxin on the ribosomal RNAs. Ribosomes do not appear to be damaged by pretreatment with bolesatine as judged by a poly(U) translation system. Thus bolesatine cannot be included in the group of protein synthesis inhibitors of plant origin known as ribosome-inactivating proteins (RIPs).

Animals↗

PubMed1992

Transrectal microwave hyperthermia for benign prostatic hyperplasia: long-term clinical, pathological and ultrastructural patterns.

Transrectal microwave hyperthermia of the prostate was administered to 191 patients with bladder outlet obstruction due to benign prostatic hyperplasia who were either at poor operative risk or who refused surgery. Patients were divided in 2 groups according to age and they underwent either 5 or 10, 60-minute sessions of hyperthermia, with a calculated intraprostatic temperature of 42.5 plus or minus 0.5C. Light and electron microscopy showed no irreversible damage at the glandular epithelium but did demonstrate a significant increase in neoformed intraprostatic capillary-like vessels. At 1, 12 and 24 months residual urine volume was significantly decreased in the majority of patients but only a minor amelioration of urinary flow rates and subjective symptoms was observed. According to maximum flow nomograms all patients were still obstructed postoperatively. Transrectal hyperthermia cannot be considered a genuine alternative to surgery for patients with bladder outlet obstruction due to benign prostatic hyperplasia.

Aged↗

PubMed1992

Ribosome-inactivating proteins from plants: present status and future prospects.

Plant ribosome-inactivating proteins (RIPs) are N-glycosidases which cleave the N-glycosidic bond of adenine in a specific ribosomal RNA sequence. Most commonly RIPs are single-chain proteins (type 1 RIPs), but some (type 2 RIPs) possess a galactose-specific lectin domain that binds to cell surfaces. The latter RIPs are potent toxins, the best known of which is ricin. RIPs have antiviral and abortifacient activities, and, in a widespread application, can also be linked to antibodies or ligands to form immunotoxins or conjugates specifically toxic to a given type of cell.

Adenine↗

PubMed1992

[Digital radiology with storage phosphors in cephalometric study in orthodontics].

Conventional radiology is continually modified with the development of digital systems which can be used for several types of radiologic examinations. Our study was aimed at evaluating the advantages of these new technologies in the orthodontic field, where the problems associated with image quality and radiation protection are major especially in young patients; the latter goal is achievable by dramatically reducing radiation dose and by avoiding repeating the exam. In our study, we compared lateral teleradiographs of the skull for cephalometric analysis obtained using conventional and digital diagnostic methods. The preliminary results demonstrated that the two imaging techniques did not differ relative to bone structure representation, even though the digital system provided better visualization of soft tissue structures. Computed radiography also allowed a marked reduction in the number of repeats and reduced radiation dose. The current disadvantages of this imaging method are the high initial cost of the equipment, reduced work rate, and the need of frequent technical assistance.

Adolescent↗

PubMed1992

[Coronary angioplasty in the aged: short and long term efficacy in patients with unstable angina].

Coronary revascularization procedures in elderly patients are associated with an increase of perioperative complications and death in comparison with younger patients. To assess if a conservative coronary angioplasty approach is useful, 54 consecutive patients (pts) with severe unstable angina were retrospectively evaluated. Mean age was 73 years (range 70-82 years). Multivessel coronary disease was present in 26 pts (48%), angina at rest within the last 2 days in 26 (48%) and an episode of myocardial infarction within 2 weeks in 21 (38%). In 51 cases, regardless of the extension of the coronary disease, only the stenosis considered "culprit" of the symptoms, as assessed by angiography and by noninvasive studies, was dilated. The angiographic success rate was 98% (53 of 54 pts). Two pts had procedure--related myocardial infarction. One patient died after emergency bypass surgery for an abrupt left anterior descending artery occlusion. The mean hospital stay was 8 days (range 2-40 days) and in 75% cases was less than 6 days. Follow-up (achieved in 51 pts) ranged from 1 to 40 months (mean 20 months). In 3 pts a second vessel was treated with a new angioplasty 15-30 days after the first procedure due to the persistence of symptoms. During follow-up three pts died (1 death was cardiac). Of the survivors, 35 were asymptomatic in moderate medical regimen, 1 required bypass surgery and 3 were managed with repeat angioplasty. Survival was 95% at 6 months and 90% at 2 years. At six months 86% of pts were event free (80% and 70% at one and two years, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1991

A cortical lectin from the oocytes of Rutilus rutilus stimulates mitogenic activity and release of soluble factors from human lymphocyte cultures and inhibits protein synthesis in a cell-free system.

1. A cortical granule lectin was isolated from vitellogenic oocytes of a bony fish, the roach Rutilus rutilus. 2. The lectin agglutinates human erythrocytes, is specific for L-rhamnose and is composed of different polypeptide subunits. 3. The lectin is the first lectin of animal origin that inhibits protein-synthesis by a rabbit reticulocyte lysate, and is also mitogenic for human lymphocytes.

Adult↗

PubMed1991

Effects of plant ribosome-inactivating proteins on ribosomes from Musca domestica.

1. Ribosomes from M. domestica larvae were isolated and their susceptibility to the action of several ribosome-inactivating proteins (RIPs) from plants was tested. 2. Ribosome-inactivating proteins inhibited, to different extents, phenylalanine polymerization by ribosomes. 3. Analysis of RNA from RIP-treated ribosomes showed the appearance of an aniline-cleavable rRNA fragment resulting from the N-glycosidase activity of the RIPs. 4. The release of adenine from saporin 6-treated M. domestica ribosomes was demonstrated by h.p.l.c. analysis.

Adenine↗

PubMed1991

[Double-contrast enema. Study of the mucosal pattern and the organ profile with conventional and digital methods].

A solid state digital system (FCR 101) was employed in our comparative evaluation of the image quality of conventional versus digital techniques in the study of colon by means of double-contrast enema. Sixty patients were examined with a single AP view, using digital radiography with 100% radiation dose and progressive 50% and 75% reductions; the radiographs thus obtained were then compared with the corresponding conventional ones. The examined parameters were organ profile and mucosal pattern. Each digital and conventional radiograph was evaluated by 2 independent radiologists and a value was given to each parameter i.e., 1 = good, 2 = sufficient, 3 = insufficient. Upon comparison of the average values obtained for digital and conventional radiographs in optimal conditions and with a dose reduced by 50%, the digital technique was seen to give a more detailed and accurate representation of both low-contrast mucosal pattern and of organ profile. With the dose reduced by 75%, a slight increase was observed in background noise which caused a slight loss in image definition, but this did not reduce image readability with respect to conventional radiographs. To conclude, the digital method with a 50% exposure reduction is to be preferred in the examination of the colon, especially in pediatric radiology; furthermore, since this technique allows better detailing at lower contrast, it is to be preferred in the study of the pathologic conditions affecting mainly/only the mucosal pattern--e.g., cancer, ulcerative colitis, Crohn's disease, and so on. An exposure dose reduced by 75% may be used for following lesions previously diagnosed and when a less detailed depiction of the mucosal pattern is enough.

Adult↗