The role of self-expanding vascular stent in superior vena cava syndrome for advanced tumours.

INTRODUCTION: Superior vena cava (SVC) syndrome (SVCS) is a life-threatening occurrence that necessitates prompt treatment. At present, endovascular stenting is proposed as a first-line treatment to relieve symptoms. We assessed the effectiveness, safety and outcome of SVC stent positioning in patients affected with advanced cancer. METHODS: Forty-two patients undergoing stent positioning in the SVC for neoplasms from January 2002 to December 2018 form the basis of this retrospective study. Demographic data, risk factors, associated diseases, symptoms at presentation according to the score proposed by Kishi and the type of SVCS according to Sanford and Doty were collected. Minor and major complications were recorded. Suspected stent occlusion was confirmed by means of recurrence of symptoms followed by a confirmatory computed tomography (CT). RESULTS: Thirty-four (81%) patients had a nonresectable lung tumour invading or compressing the SVC. Five (12%) patients had a non-Hodgkin's lymphoma, and three (7%) had metastatic lymphadenopathies. Nitinol stents (Memotherm®) were employed in 19 (45%) patients, and steel stents (Wallstent™) in the remaining 23 (55%) patients. Thirty-five (85%) patients died during follow up for disease progression and the overall survival rate at 24 months was 11% (standard error (SE)=0.058). Thirteen patients (32%) had a recurrence of SVCS because of stent thrombosis in three (23%) and extrinsic compression from uncontrolled cancer progression in ten (77%). The overall symptom-free interval at 24 months was 57% (SE=0.095). CONCLUSIONS: We recommend the use of the endovascular procedure as a first-line treatment in locally advanced or metastatic tumour in the presence of SVCS.

Perioperative red blood cell transfusion and outcome in stable patients after elective major vascular surgery.

OBJECTIVES: Definitive evidence that red blood cell transfusion improves outcome after vascular surgery is lacking. The aims of the study were to determine, among stable consecutive patients who underwent elective major vascular surgery, (1) the association between postoperative transfusion and 30-day death, myocardial infarction, and both, and (2) and if this association differs according to the presence of postoperative anaemia (haemoglobin value less than 9.0 g/dL within 7 days after surgery). METHODS: A retrospective observational study was conducted on 359 patients prospectively screened according to the ACC/AHA guidelines for preoperative risk in non-cardiac surgery. Main outcome was 30-day death; secondary outcomes 30-day myocardial infarction, and composite of 30-day myocardial infarction or death. RESULTS: Of the patients included, 95 (26.5%) received at least one unit of red blood cells. Patients who received transfusion had a significantly increased hazard of 30-day death (hazard ratio [HR] 11.72, 95% confidence interval [CI] 3.92-35.10; p<0.0001), myocardial infarction (HR 3.3, 95% CI 1.7-6.1; p=0.0003), and both (HR 4.0 95% CI 2.2-7.3; p<0.0001). Such associations held even after adjusting for baseline characteristics, surgical risk, bleeding, and propensity to receive transfusion. There was a significant interaction between transfusion and postoperative anaemia (p=0.012). In patients without anaemia, transfusion was associated with higher risk of 30-day death (HR 19.20, 95% CI 3.99-92.45; p=0.007), myocardial infarction (HR 5.05, 95% CI 2.23-11.44; p=0.0001), and both. Conversely, in patients with anaemia this association was not significant. CONCLUSIONS: In patients who underwent elective major vascular surgery, perioperative transfusion was associated with a significantly increased risk of 30-day events which was more attributable to patients with lesser degree of anaemia. Our data caution against the use of liberal transfusion in stable vascular surgery patients.

Correlation between animal and human brucellosis in Italy during the period 1997-2002.

The aim of this study was to test the hypothesis that brucellosis in Italy is a food-borne, rather than an occupational disease. This hypothesis was tested using data for both human and animal populations from the period 1997-2002. The correlation between the distribution of the disease in the human, sheep and goat populations was analysed, as were the risk factors for the disease, with respect to gender, age, occupation and residence of the individuals involved. Notifications of human brucellosis, which are mandatory in Italy, reach a peak between April and June. However, considering the standard incubation period of 2-4 weeks, and the fact that lamb slaughter is traditionally at a peak during the Easter period, it might be expected that occupational exposure would result in a peak of human cases between March and May. The observed peak between April and June could be related to the production and consumption of fresh cheese, starting just after lamb slaughter. The age of patients showed a fairly uniform distribution, and analysis of incidence rates of human brucellosis between 1997 and 2002 showed that the incidence rates were consistent with an occupational exposure risk of about 25%.

Activation of metallothionein expression is potentiated by DNA sequences present in the herpes simplex virus thymidine kinase gene.

A mouse cell line (Ltk-aprt-) which is resistant to the anti-viral effects of interferon also has a reduced ability to synthesize metallothionein on exposure to cadmium. Like the ability to respond to interferon, cadmium-induced metallothionein synthesis is restored to wild-type levels in clones obtained by introducing a thymidine kinase gene into Ltk-aprt-cells. Transfection of other genes does not have such an effect. Since metallothionein expression is also activated by interferon the results suggest that the regulation of several genes which are responsive to interferon can be modulated by specific sequences present in the Herpes virus thymidine kinase gene.

Enhanced clearing of Helicobacter pylori after omeprazole plus roxithromycin treatment.

The in vitro antibacterial activity of omeprazole against eight strains of Helicobacter pylori was evaluated. Minimum inhibitory concentration (MIC) values were 32 micrograms/ml and 64 micrograms/ml (MIC50 and MIC90 respectively). We performed a randomized single blind study comparing the efficacy of omeprazole alone (for 4 weeks) or combined with roxithromycin (for 2 weeks) in the treatment of duodenal ulcer and chronic active gastritis associated with H. pylori infection, H. pylori was eradicated in 75% of patients treated with omeprazole alone whereas the patients treated with the combination of these drugs were completely free from H. pylori at the end of the therapy.

Biochemical characterization of a thialysine-resistant clone of CHO cells.

The intracellular transport and the activation of lysine, thialysine and selenalysine have been investigated in a thialysine-resistant CHO cell mutant strain in comparison with the parental strain. The cationic amino acid transport system responsible for the transport of these 3 amino acids shows no differences between the 2 strains as regards its affinity for each of these amino acids. On the other hand the Vmax of the transport system in the mutant is about double that in the parental strain. The lysyl-tRNA synthetase, assayed both as ATP = PPi exchange reaction and lysyl-tRNA synthesis, shows a lower affinity for thialysine and selenalysine than for lysine in both strains; in the mutant, however, the difference is even greater. Thus the thialysine resistance of the mutant is mainly due to the properties of its lysyl-tRNA synthetase, which shows a greater difference of the affinities for lysine and thialysine with respect to the parental strain.

Isolation and properties of a thialysine-resistant clone of CHO cells.

A variant clone of Chinese hamster ovary (CHO) cells resistant to thialysine has been isolated. It maintains the phenotypic properties even after 250 generations in medium without thialysine. Growth rate, cell viability and protein synthesis rate of the variant are much less affected by thialysine than the parental strain. In both the parental strain and the variant, thialysine acts in competition with lysine as indicated by the fact that all thialysine effects can be completely reversed by lysine.

A validated method for the determination of paracetamol and its glucuronide and sulphate metabolites in the urine of HIV+/AIDS patients using wavelength-switching UV detection.

Paracetamol is a safe drug which has been used as an in-vivo probe to determine phase II metabolism in a HIV+/AIDS population. Due to the biohazard nature of HIV-infected samples, a high performance liquid chromatography (HPLC) assay which offers minimal sample manipulation and maximal specificity was developed. This reverse-phase HPLC method uses wavelength-switching UV detection for the simultaneous determination of paracetamol and its glucuronide and sulfate metabolites in HIV-infected urine samples. The solvent systems involves a simple isocratic elution with a composition of 50 mM sodium acetate buffer, pH adjusted to 3.5; acetonitrile (96:4 v/v) modified with 0.35% trifluroacetic acid. The validated method is highly reproducible with an inter-assay variation of < 7%. This method also shows good precision and sensitivity, making it an ideal assay for phenotyping studies to determine the extent of glucurondiation and sulfation activities.

In vitro susceptibility to quinolones and other antimicrobial agents of Staphylococcus species isolated from immunocompromised patients.

A total of 237 Staphylococcus strains were isolated from different kinds of body tissues and fluids from immunocompromised patients admitted to the Hematology Department of Pescara Hospital (Italy). These strains, collected from November 1987 to September 1988, were studied for their susceptibility to methicillin and other drugs commonly used in therapy, and the minimum inhibitory and minimum bactericidal concentrations of five quinolones were determined. The killing curve of ciprofloxacin compared with nalidixic acid was determined. The results show a considerable activity of fluoroquinolones against all strains studied.

Evaluation of azlocillin-amikacin combination for empirical therapy of infection in febrile neutropenic patients.

We have evaluated the azlocillin-amikacin combination, given at a daily dose of 200 mg/kg and 15 mg/kg respectively, in the treatment of 62 consecutive febrile granulocytopenic patients (less than 500 PMN/microliters) affected by hematological disease. The effectiveness of the treatment was assessed in 60 patients, 44 (73%) of whom responded within 96 hours from the beginning. 36 of the responders showed microbiological and clinical infections, 2 had clinically documented pneumonia and 6 a possible infection. No improvement was obtained in 16 patients; 7 of whom suffered from clinical and microbiological infection, 2 from pulmonary mycosis, 4 from possible infection and 3 from doubtful infection. Seven of these patients subsequently responded to a proven antibiotic treatment, while only one of the remaining responded to a second-line empirical antibiotic schedule. These results suggest that the combination of azlocillin-amikacin was able to overcome about two-thirds of the infections, representing an effective remedy for the empiric treatment of febrile neutropenic patients.

Clinical efficacy and in vitro activity of the ciprofloxacin-azlocillin combination (ratio 1:10) against gram-negative bacteria from non-neutropenic haematologic patients.

The authors report treatment of eighteen haematologic patients (twelve male, six female, age between 21 and 78 years), suffering from upper respiratory tract (ten patients) and/or lower urinary tract (eight patients) infections caused by Gram-negative germs, with a combination of ciprofloxacin-azlocillin in the ratio 1:10. Before treatment, the Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Fractional Inhibitory Concentration (FIC) index of Gram-negative isolates from patients for the ciprofloxacin-azlocillin combination were evaluated. The in vitro experiments revealed a synergistic activity of the combination for 85% of isolates, while at the same concentration ciprofloxacin alone was 100% effective, and azlocillin alone was 50% effective. The combination was administered to patients as follows: ciprofloxacin: 750 mg "per os" every 12 h; azlocillin 5 g intravenously every 8 h for a therapeutic cycle of 8 days. Seventeen of the eighteen patients that were treated with the combination showed complete eradication of the causative pathogen, sixteen of the eighteen patients recovered fully, whereas the other two showed significant improvements. The tolerability of the combination was excellent in seventeen patients and only one patient developed symptoms of mild gastric intolerance. The results presented here warrant further interest in studies of this antibiotic combination.

In vitro activity of netilmicin alone and in combination with azlocillin, mezlocillin and imipenem against 149 coagulase-negative staphylococci.

Coagulase-negative staphylococci (CNS) have long been regarded as innocuous skin commensals with little pathogenic potential but they have recently become, under appropriate conditions, an important cause of infections. In fact, infections caused by CNS are an increasing problem especially, but not exclusively, in immuno-compromised patients. A total of 149 strains of CNS were identified from 47 patients admitted to the Haematology Department of Pescara Hospital from October 1986 to November 1987. The strains, isolated from different parts of the body and characterized by their methicillin susceptibility, were classified by API-Staph in 11 different groups. MICs and MBCs of netilmicin alone and combined with azlocillin, mezlocillin and imipenem were studied. For all combinations FIC and FBC indices were determined. The killing kinetics of the drugs mentioned above were also determined. Except for a few microorganisms (less than 5%), the associations showed a synergic or additive effect.

Studies on recognition of selenahomolysine by aminoacid transport systems and aminocyl-tRNA synthetase.

In E. coli, Se-3 aminopropylselenocysteine or selenahomolysine (SeHL) does not affect intracellular lysine transport, i.e. it cannot bind E. coli lysine transport systems. In CHO cells it inhibits cationic aminoacid transport system, but only in the presence of Na+, this indicating that it behaves like polar neutral aminoacids. On the other hand, it poorly affects leucine transport both in the presence and in the absence of Na+. SeHL is not activated by aminoacyl-tRNA synthetase preparations from bacterial and mammalian sources, thus it cannot be utilized for protein synthesis.

Thialysine and selenalysine incorporation into CHO cell proteins and its effects on cell growth.

CHO cells can incorporate into proteins both thialysine and selenalysine when both are present together in the culture medium. Thialysine and selenalysine inhibit cell growth and cell viability. The inhibitory effect of either analog is additive. The inhibition of cell viability is related to the extent of protein lysine substitution by thialysine or selenalysine; it is however irrelevant whether lysine is substituted by one or the other analog or by both.

Ejection phase indexes with apexcardiography. Comparison with echocardiographic and angiographic parameters.

The reliability of a new noninvasive method for evaluating ejection fraction and the mean velocity of circumferential fiber shortening by apexcardiography and carotid pulse tracing has been evaluated. Three groups of subjects were considered. Group 1: 30 normal subjects (mean age 43 years); Group 2: 34 patients with aortic valve disease (mean age 51 years); Group 3: 76 patients with coronary artery disease (mean age 50 years). The mechano-cardiographic tracing points were acquired by an ultrasonic digitizing system and compared with the same indexes measured from the ventriculogram. In 53 patients M-mode echocardiographic evaluations also were performed. The correlations between the apexcardiographic derived ejection phase indexes and the angiographic measurements were highly significant in all subjects and in each group of patients. The correlations between the ejection phase indexes determined by echocardiography and the same angiographic data were also significant, but the r-values were somewhat lower than those found between the apexcardiographic and angiographic parameters in the same patients. Our results have assessed the reliability of this new method and demonstrated that this noninvasive technique can be applied not only in coronary disease but also in aortic valve disease and in normal subjects. It can be concluded that the apexcardiographic evaluation of cardiac performance appears applicable to patients in whom a means of assessing and sequentially following ventricular function is indicated.

Salmonella typhimurium-endocarditis secondary to an acquired environmental infection: a case report.

A diabetic, cardiopathic and anemic 44-year-old farmer presented with a seven-day history of remittent fever with evening peaks. Two months before he had undergone amputation of the V-finger of the left hand secondary to a phlegmon caused by an agricultural injury. Prior to amputation, anaerobic culture analysis of phlegmon-pus and selective procedures used to isolate Gram-positive cocci and/or Pseudomonas spp. resulted negative. The diagnosis of endocarditis was supported by isolation of S. typhimurium from blood and by echocardiography showing endocarditic lesions. The source of infection was identified by PCR ribotyping as the same Salmonella typhimurium strain that was present, but not sought, both in the anatomic explanted tissues and from blood samples of the patient. The infection was successfully treated with a combination of gentamicin and ampicillin with consequent improvement in the general clinical picture of the patient. We believe this is the first reported case of S. typhimurium-endocarditis secondary to a phlegmon resulting from an environmental source of infection.

Comparative analysis of two systems for HCV genotyping.

The HCV genotype can be determined by PCR using nested primers to structural or non-structural HCV regions, followed by hybridization analysis of the amplified products. In this study, two different systems, both based on PCR and hybridization analysis, were used to determine HCV genotype in 32 HCV positive patients at the Clinic of Infectious Diseases, University of Chieti. The main difference between these commercially available systems lies in the different PCR target. Amplification of PCR targets was obtained from all samples. Hybridization analysis gave unequivocal results for all samples with both methods, yielding a 100% rate of genotype determination, with a complete correlation at the genotype level. A lower concordance at subtype level (65% concordance) was found, due only to two types of discrepancies. Both methods proved easy to use in our hands, adding evidence to their potential usefulness and reliability in clinical settings.

Utilization of lysine analogs by a lysine-requiring E. coli mutant.

Thialysine and selenalysine cannot substitute lysine as a growth factor for a lysine-requiring E. coli mutant, but can nevertheless be utilized for protein synthesis in the presence of lysine. In order to have information about the effects of lysine on the utilization of the two analogs, the extent of the incorporation of the three aminoacids into newly synthesized proteins has been determined. The analog starts to be utilized by cells growing in a medium containing either analog and lysine when lysine concentration becomes very low. Of the two analogs, thialysine is more easily utilized. In fact thialysine can be utilized when the lysine/thialysine ratio in the medium is 1/25. Selenalysine starts to be utilized when the lysine/selenalysine ratio is 1/200.

Thialysine utilization for protein synthesis by CHO cells.

Chinese Hamster Ovary (CHO) cells utilize thialysine when added to the culture medium. Thialysine utilization is prevented by increasing lysine concentration in the medium, thus indicating that thialysine is utilized in substitution for and in competition with lysine. Almost all thialysine disappeared from the medium is recovered in cell protein hydrolysates. Thialysine is used for protein synthesis in substitution for lysine, and up to 10% of lysine can be substituted.

Thialysine utilization by thialysine resistant CHO cells.

Thialysine resistant CHO cells utilize thialysine added to the culture medium to a lesser extent than the parental cells. Thialysine is utilized in protein synthesis and it is incorporated into proteins in place of lysine. The parental strain substitutes up to 11% of protein lysine by thialysine, while variant cells substitute a maximum of 5% of protein lysine.