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V Testa

Publications and source records attributed to V Testa.

At least 19 recordsLinked to original sources
PubMed2006

An enigmatic long-lasting gamma-ray burst not accompanied by a bright supernova.

Gamma-ray bursts (GRBs) are short, intense flashes of soft gamma-rays coming from the distant Universe. Long-duration GRBs (those lasting more than approximately 2 s) are believed to originate from the deaths of massive stars, mainly on the basis of a handful of solid associations between GRBs and supernovae. GRB 060614, one of the closest GRBs discovered, consisted of a 5-s hard spike followed by softer, brighter emission that lasted for approximately 100 s (refs 8, 9). Here we report deep optical observations of GRB 060614 showing no emerging supernova with absolute visual magnitude brighter than M(V) = -13.7. Any supernova associated with GRB 060614 was therefore at least 100 times fainter, at optical wavelengths, than the other supernovae associated with GRBs. This demonstrates that some long-lasting GRBs can either be associated with a very faint supernova or produced by different phenomena.

Journal Article↗
PubMed2001

The effects of prolonged peritendinous administration of PGE1 to the rat Achilles tendon: a possible animal model of chronic Achilles tendinopathy.

We studied the effects of peritendinous Achilles tendon injections of prostaglandin E1 (PGE1) on the Achilles tendon of rats. Five groups of Sprague-Dawley rats (n = 24 each) were studied. Groups 1 to 4 received weekly peritendinous injections. In group 1, one side was injected with 800 ng of PGE1 in 0.5 ml of 0.9% NaCl and the contralateral side was injected with 0.5 ml of 0.9% NaCl. In group 2, one side was injected with 800 ng of PGE1. In group 3, one side was injected with 0.5 ml of 0.9% NaCl. In group 4, a syringe needle was inserted in the peritenon unilaterally, but no substances were administered. In groups 2, 3, and 4, the contralateral tendon was used as the control. In group 5, treatment was not administered. Eight rats in each group were killed at each time point, after 7, 21, and 35 days of treatment. On day 7, values for average water content and average wet weight of the tendons treated with PGE1 were significantly higher than those in the control tendons (analysis of variance [ANOVA]; P = 0.02), with a histological picture of acute inflammation. On day 21, approximately half of the PGE1-treated tendons showed fibrosis of the paratenon, with adhesions and intra-tendinous degeneration, with the other half still showing a picture of acute inflammation. On day 35, all of the PGE1-treated tendons showed fibrosis of the paratenon, with adhesions and intra-tendinous degeneration. At all time points, there was no evidence of pathology in the tendons that had not received PGE1. Sham peritendinous injections and injections of normal saline did not produce inflammation in the Achilles tendons. Initially, local administration of PGE1 produced acute inflammation of the tendon and its surrounding tissues. Prolonged PGE1 administration produced peri- and intra-tendinous degeneration, providing a cheap, reproducible model of Achilles tendinopathy, which would allow studies of the effects of conservative and surgical management of the condition.

Achilles Tendon↗
PubMed1999

Ultrasound-guided percutaneous longitudinal tenotomy for the management of patellar tendinopathy.

Thirty-eight athletes with unilateral patellar tendinopathy (17 with a tendinopathy of the main body of the tendon, and 21 with an insertional tendinopathy) underwent ultrasound-guided multiple percutaneous longitudinal tenotomy under local anaesthetic infiltration after failure of conservative management. Thirty-four patients were reviewed at least 24 months after the operation. Sixteen patients were rated excellent, nine good, eight fair, and five poor. Nine of the 13 patients with a fair or poor result had an insertional tendinopathy, and eight of them underwent a formal exploration of the patellar tendon. Before the operation, there were some areas of altered echogenicity at and around the site of involvement. These were still visible 6 wk after surgery in 70% of the patients. At the latest follow-up, in the patients with an excellent or good result, the tendon was generally isoechogenic but slightly thicker (P = 0.06) than the normal contralateral. In the patients with a fair or poor result, the tendon was significantly thicker than the contralateral (P = 0.03), and showed some areas of mixed echogenicity. In the patients in whom the procedure was successful, the thicker operated tendon did not interfere with physical training. Bilateral isokinetic peak torque (Nm), average work (Joules), and average power (Watts) were tested at 90 degrees x s(-1). Immediately before the operation, there was no significant difference in peak torque, but total work and average power were significantly lower in the limb to be operated (0.01 < P < 0.05). By the end of the study, although peak torque was, on average, within 7% of the unoperated limb, total work and average power were still significantly lower than in the unoperated limb (0.01 < P < 0.04). Percutaneous longitudinal internal tenotomy is simple, can be performed on an outpatient basis, requires minimal follow-up care, does not hinder further surgery should it be unsuccessful, and, in our experience, has produced no significant complications. In our hands, it has become the first line operative intervention in the treatment of chronic patellar tendinopathy after failure of conservative management. However, patients should be advised that, if they suffer from an tendinopathy at the attachment of the patellar tendon at the lower pole of the patella, a formal surgical exploration with stripping of the paratenon is preferable.

Adolescent↗
PubMed1998

The disappearing exostosis? A report of an unusual case.

A girl aged 11 years was referred to us with a medial upper right tibial exostosis. As the lesion was asymptomatic, surgery was not undertaken. The patient defaulted from follow up, and, when reviewed 32 months later, there was no clinical or radiographic evidence of the exostosis. Spontaneous involution of an exostosis may occasionally occur in childhood.

Child↗
PubMed1997

Central venous thrombosis: an early and frequent complication in cancer patients bearing long-term silastic catheter. A prospective study.

Studies on catheter-related central venous thrombosis (CRCVT) have been focused mainly on clinically evident CRCVT due to occlusive thrombi, underestimating therefore the actual thrombosis prevalence. This prospective study was aimed at evaluating prevalence, timing and evolution of thrombosis, and identifying involved veins and risk factors in cancer patients (pts) undergoing percutaneous subclavian central venous catheterization (CVC) for chemotherapy, parenteral nutrition or both. We enrolled 127 consecutive pts requiring partially or totally implanted central venous silastic catheters. The study protocol included peripheral phlebography (P) at day 8, 30 and every two months following CVC and/or when clinically indicated, along with peripheral and pullout P on catheter withdrawal. A quantitative scale was developed to evaluate thrombus grading in subclavian, innominate and cava veins. Age, sex, coagulation profile tumor histotype, metastases, therapy, catheter type, and catheter insertion side were also investigated. Only pts who underwent at least two P were evaluated, and chi 2 test was adopted for statistical analysis. Altogether, 95 pts were evaluable. CRCVT was observed in 63/95 (66%) pts. At day 8, 30 and 105 (representing the median days in which first, second and last P were performed) CRCVT was evidenced in 64%, 65% and 66% of the pts, respectively. Thrombus grading did not differ among first, second and last P. CRCVT was symptomatic in 4/63 (6%) pts. Thrombosis prevalence was higher in subclavian (97%) with respect to innominate (60%) or cava (13%) veins (p < 0.001). Thrombosis was higher in left subclavian catheters (14/16; 87.5%) than in right ones (49/79; 62%), p < 0.01. No associations were established between CRCVT and other investigated parameters. Our data show a very high actual frequency of CRCVT in cancer pts, and emphasize that first days following CVC are at the highest risk for CRCVT development. Based on our results, a study on short-term antithrombotic prophylaxis in cancer pts requiring CVC is warranted. Finally, our data indicate that left subclavian vein catheterization represents a risk factor for CRCVT.

Adolescent↗
PubMed1997

Single-needle celiac plexus block: is needle tip position critical in patients with no regional anatomic distortions?

BACKGROUND: The "single-needle" celiac plexus block is becoming a popular technique. Despite different approaches and methods used to place the needle, the success of the block depends on adequate spread of the injectate in the celiac area. In the present retrospective study, the influence of needle tip position in relation to the celiac artery on injectate spread was evaluated. METHODS: Among 138 cancer patients subjected, via an anterior approach, to computed tomography (CT)-guided single-needle neurolytic celiac plexus block, a radiologist, blinded to the aim of the study, retrospectively selected 53 cases with normal anatomy of the celiac area as judged by CT. The decision was based on images obtained before the block. Patients were then classified into either group A (29 patients), in whom the needle tip was caudad to the celiac artery, and group B (24 patients), in whom it was cephalad. To evaluate CT patterns of neurolytic (mixed with contrast) spread, the celiac area was divided on the frontal plane into four quadrants: upper right and left and lower right and left, as related to the celiac artery. Patient assessments by visual analog scale were reviewed to evaluate the degree of pain relief. Pain relief 30 days after block was judged as long-lasting. The patterns of contrast spread in relation to the needle position and pain relief according to the number of quadrants with contrast were analyzed. RESULTS: The percentage of cases with four quadrants with contrast was higher when the needle tip was cephalad (58%, group B) than when it was caudad (14%, group A) to the celiac artery (P < 0.01). The percentage of patients with four and three quadrants with contrast was also higher in group B at 79% than in group A at 38% (P < 0.01). A significant difference in long-lasting pain relief was observed between patients with four quadrants with contrast (18 of 18, 100%; 95% confidence interval [CI], 81-100%) and patients with three quadrants with contrast (5 of 12, 42%; 95% CI, 15-72%) (P < 0.01). No patients showing two or one quadrant with contrast had long-lasting pain relief. CONCLUSIONS: These findings suggest that, when the celiac area is free from anatomic distortions, and the single-needle neurolytic celiac plexus block technique is used, the needle tip should be positioned cephalad to the celiac artery to achieve a wider neurolytic spread. It also appears that only a complete (four quadrants) neurolytic spread in the celiac area can guarantee long-lasting analgesia.

Adult↗
PubMed1997

[The radon risk in Lombardy].

We investigated the geographical distribution of lung cancer mortality rates in some Italian regions, Lombardy and Emilia-Romagna in particular, where the investigation was mainly focused on the risk related to the presence of radon inside dwelling-houses. We referred to the death certificates provided by the Central Institute of Statistics (ISTAT) relative to the years 1980-1988 to calculate the relevant mortality rates. Mortality rates appear higher in some northern than in southern regions and in the islands and also (> a factor of 10) in the male than in the female population; the mortality rates in the male population exhibit a linear correlation with past cigarette smoking. The death rates in the male population (age range: 35-64 years) in northern Italy average 100 events/100,000 inhabitants, but several local health centers in Lombardy at the foot of the Alpine range, north of the Po River, have mortality rates over 50% higher than estimated rates. We considered radon exposure in Lombardy dwelling-houses. The Alps are rich in granite rocks, with 50-150 Bq/kg uranium concentrations, which produce the sediments, sands and gravels making the ground of the Lombardy plain. A recent survey of indoor radon exposure levels showed average values around 100 Bq/m3. The National Academy of Sciences (Washington, DC) has presented a formula to calculate the relative risk of lung cancer related to radon exposure during a lifetime. When this model was applied to excess events in Lombardy, acceptable agreement was found with the assumption that excess deaths are ascribable to higher radon exposure levels. We also compared Lombardy with Emilia-Romagna where the sediments and soil in the plain come from the Apennine range where calcareous rocks have low uranium content. Radon exposure levels in Emilia-Romagna were around 50 Bq/m3 and the radon risk factor in this region is therefore not particularly significant.

Adult↗
PubMed1996

Percutaneous longitudinal tenotomy in chronic Achilles tendonitis.

In the period from August 1989 through December 1992, 42 track and field athletes with unilateral Achilles tendonitis and/or peritendinitis were operated using multiple percutaneous longitudinal tenotomy under local anesthesia following failure of conservative treatment. Patients were reviewed in a special clinic over three consecutive days at an average of 19.2 (9.4) months from the operation. Of the 42 patients operated, 36 (86%) attended. On this occasion, only subjective assessment was carried out. Of the other six patients, four were interviewed by telephone using the same questionnaire; two were lost to follow-up. The results in 25 patients (59.5) were rated as excellent, 11 (28.2%) as good, 4 (9.5%) as fair, and 2 (4.8%) as poor.

Achilles Tendon↗
PubMed1996

Giant spinal cord ependymoma in a child. Case report.

Ependymomas of the spinal cord extending to more than ten vertebral segments are rare. A case of a 14-month-old child is described and the other 13 reported cases are reviewed. The finding of a very extensive tumor (from T5 to L5) after only 14 months of life suggests that in our case the tumor was present since birth. Magnetic resonance well shows the real extent of the tumor in height and its different components. Complete removal is often possible even in very extensive ependymomas and results in clinical improvement. Postoperative radiotherapy is necessary only for incompletely removed or malignant ependymomas.

Ependymoma↗
PubMed1995

Antithrombin III deficiency as a risk factor for catheter-related central vein thrombosis in cancer patients.

The fibrin sleeve of venous catheters (VC) and parietal thrombi represent frequent and dangerous side-effects of central venous catheterization (CVC), due to the risk of embolism. Reduced levels of coagulation clotting factors inhibitors (such as Antithrombin III) are known to be associated with increased thrombogenic risk. The aim of this study was to evaluate the role of Antithrombin III (AT III) deficiency as a risk factor for thrombosis in cancer patients undergoing CVC. The study groups included patients with a reduced AT III activity (< 70%, 20 consecutive patients) and with normal AT III values (> 70%, 20 randomly selected patients), requiring a VC for chemotherapy and/or total parenteral nutrition. The study protocol included evaluation of Hb, PLTs, PT (INR), aPTT, Fibrinogen and AT III at days 0, 1, 3 and 8 after CVC and upon VC removal. Peripheral and pullout phlebographies were performed in all patients on catheter withdrawal. A quantitative scale was developed to evaluate both VC and parietal thrombus degree in each catheter-containing venous segment (subclavian, innominate, superior vena cava); the sum of the mean values was defined as overall thrombus. The average VC dwelling time was similar in both groups. There were no significant differences in Hb, PLTs, PT (INR), aPTT, Fibrinogen and in the remaining parameters of the study between the two groups. The group with AT III deficiency presented a higher degree of both parietal (p < 0.05) and overall thrombus (p < 0.02). Data showed a higher severity of CVC-related thrombosis in patients with AT III deficiency than in the control group. Further studies are needed to evaluate whether the therapeutically-induced normalization of AT III levels can reduce the thrombosis degree.

Adult↗
PubMed1995

Time-dependent efficacy of bacterial filters and infection risk in long-term epidural catheterization.

BACKGROUND: Epidural infection represents a serious albeit infrequent complication of long-term epidural catheterization. The catheter hub is regarded as the main point of entry for microorganisms among the three possible routes (hematogenous, insertion site, hub) of microbial colonization of the inserted catheter. The current study was aimed at evaluating whether frequent changing of antimicrobial filters carries an increased risk of catheter hub contamination and the time-dependent efficacy of commonly used antimicrobial filters after prolonged use. METHODS: In the first part of the study, a microbiologic survey (skin, filter, hub, and catheter tip) was performed weekly in a group of 47 patients with cancer bearing subcutaneously tunneled catheters managed at home. Subsequently, the time-dependent efficacy of 96 micropore filters (32 Portex, 32 Sterifix-Braun, 32 Encapsulon TFX-Medical) differing in surface areas and/or composition of the filtering membrane was evaluated in a laboratory study. Filters were perfused, under the usual conditions of clinical use (flow resistance, injection pressure, temperature), every 8 h up to 60 days, with 5 ml of two different analgesic solutions, either sterile or containing 1.5 x 10(5)/ml of Streptococcus milleri I. Eight filters of each type subsequently were flushed with a S. milleri suspension (0.5 McFarland) after 7, 14, 28, and 60 days of continuous perfusion, and the resulting filtrates were cultured. RESULTS: In 16 of 19 positive hub cultures, the same microorganisms (species, biotype, antibiotype) were cultured from skin and filters. A statistically significant positive trend was found between the number of filter changes and the rate of positive hub cultures (chi 1(2) trend 5.11; P = 0.02). A high correlation coefficient was found between number of positive skin cultures and number of positive filtrates (r = 0.88; P = 0.01) and between number of positive filtrates and number of positive hub cultures (r = 0.93; P = 0.003). Cultures obtained from Portex and Sterifix-Braun filters yielded no bacterial growth (64/64) throughout the study period. Cultures from Encapsulon TFX-Medical filters showed bacterial growth 2/8 at seventh day, 7/8 at the 14th day, and 16/16 from the 28th day onward. CONCLUSIONS: Our data indicate significant correlation between the incidence of catheter hub colonization and the filter-change frequency, when the skin close to the filter-hub connection is contaminated. Our results also show that Portex and Sterifix-Braun bacterial filters, when perfused with reduced volumes at low injection pressures, maintain an unmodified antimicrobial function for at least 60 days. Based on these data, it appears clinically feasible to reduce the frequency of filter changes during long-term epidural catheterization, with a consequent possible decrease of epidural catheter colonization.

Ambulatory Care↗
PubMed1995

Nonsteroidal antiinflammatory drugs for cancer pain: comparison between misoprostol and ranitidine in prevention of upper gastrointestinal damage.

PURPOSE: The prophylactic strategy of nonsteroidal antiinflammatory drug (NSAID)-induced upper gastrointestinal (UGI) damage has largely been studied in arthritic patients, but not in cancer patients. The efficacy of misoprostol and ranitidine in the prevention of gastroduodenal damage in patients taking diclofenac for their cancer pain has been compared in this study. PATIENTS AND METHODS: Patients who needed high-dose (200 to 300 mg/d) diclofenac for cancer pain and without mucosal lesions at baseline gastroduodenal endoscopy were randomized to receive misoprostol (200 micrograms twice daily; M group) or ranitidine (150 mg twice daily; R group). UGI endoscopy was repeated after 4 weeks. RESULTS: Twenty-three patients treated with misoprostol and 26 treated with ranitidine concluded the study. The M group showed a significantly (P < .02) lower incidence of gastroduodenal lesions (two patients; 8.7%) than the R group (10 patients; 38.5%). Gastric ulcers occurred in one (4%) misoprostol-treated patient and in six (23%) ranitidine-treated patients. Six of seven patients with ulcers were asymptomatic. Seventy-one percent and 86% of ulcers occurred in patients older than 60 years and in those who received greater than 3.1 mg/kg of diclofenac, respectively. CONCLUSION: Misoprostol was significantly more effective than ranitidine in the prevention of gastroduodenal lesions in cancer patients receiving diclofenac.

Adult↗
PubMed1994

Anaerobic threshold determination in master endurance runners.

Twenty middle aged endurance runners underwent physiological testing to determine their maximal oxygen uptake (VO2max), lactate threshold, ventilatory threshold, the slope variation point (SVP) of the linear relationship between running speed (RS) and heart rate (HR) both on the treadmill and during a field test, and the onset of blood lactate accumulation point. The RS, HR, VO2 and blood lactate concentration at which the different thresholds occurred were highly correlated (0.70 < r < 0.95; p < 0.01). The various indices of aerobic-anaerobic transition in the master athletes examined were shown to occur at a comparable percentage of their VO2max as compared to their younger counterparts. The tests developed for, and commonly used in adult athletes, are equally valid in this age group.

Aged↗
PubMed1994

Molded arthroplasty and transfer of the extensor hallucis brevis tendon. A modification of the Keller-Lelievre operation.

The Keller-Lelievre technique for hallux valgus correction was modified by detaching the extensor hallucis brevis tendon from the proximal phalanx, and reattaching it on the medial sesamoid. Thirty-five consecutive patients were assigned randomly to 1 of 2 groups. Patients in Group 1 received the modified operation, and the original Keller-Lelievre technique was used for the control group. The only significant radiographic difference at 6 months was the distance between the first and the fifth metatarsal heads. There were only slightly significant differences in function and in pain relief between the 2 groups at the 6th postoperative month. At 3 years, these differences were greater, with the group treated by the modification described herein, retaining significant correction and showing better functional results.

Aged↗
PubMed1994

Proteases and antiproteases in cartilage homeostasis. A brief review.

Among other factors, articular cartilage degeneration is caused by proteolytic enzymes. Different cell types of the synovial fluid and/or the synovial membrane and cartilage release specific proteases. Normally, these are finely tuned with their inhibitors. When this balance is altered, the proteolytic action may prevail, producing tissue damage, cartilage disruption, and ultimately a full osteoarthritic picture. The protease antiprotease mechanism opens new perspectives in the diagnosis and pharmacologic management of osteoarthritis. Early diagnosis and improved monitoring of the evolution of the disease are made possible, and a more rational therapy against cartilage disruption becomes feasible.

Cartilage, Articular↗