Left ventricular systolic and diastolic function after anthracycline chemotherapy in childhood.

BACKGROUND: In childhood, late cardiotoxicity is characterized by inappropriately thin wall and consequent increased end-systolic wall stress, but the associations of impaired left ventricular geometry and function occurring under these circumstances need further investigation. HYPOTHESIS: The purpose of this study was to assess anthracycline late effects on the relationships occurring between increased end-systolic stress (ESS) and changes in both M-mode systolic measurements (i.e., endocardial and midwall fractional shortening) and Doppler diastolic indices in the pediatric age. METHODS: The population consisted of 101 children treated with anthracyclines for at least 12 months and 91 healthy children. Using M-mode echocardiography, end-systolic wall stress was calculated as index of afterload, and endocardial and midwall fractional shortening as systolic indices. Doppler transmitral measurements were made as diastolic indices. RESULTS: Patients treated with anthracyclines showed significantly lower relative wall thickness and left ventricular mass index, greater end-systolic wall stress, reduced endocardial and midwall fractional shortening and peak E/A ratio, prolonged deceleration, and isovolumic relaxation times. Direct relationships were found between end-systolic wall stress and both endocardial and midwall shortening. The use of midwall shortening in the relation showed a greater, but not significant increase (from 3 to 6%) in the proportion of patients with depressed systolic function than did endocardial shortening. In the anthracycline group, end-systolic wall stress was also inversely related to relative wall thickness and directly to isovolumic relaxation time. CONCLUSIONS: In childhood, reduced myocardial thickness and increased afterload explain much of systolic and diastolic dysfunction of late anthracycline toxicity. Midwall fractional shortening does not seem to add useful information for identifying subsets of children more prone to the development of heart failure.

Arterial distensibility and ambulatory blood pressure monitoring in young patients with neurofibromatosis type 1.

Vascular disease is an underestimated complication of neurofibromatosis type 1 (NF1). The few studies available on this disease are based on case reports. The purpose of this study was to evaluate the relationship between 24-h systolic blood pressure (SBP) and 24-h heart rate obtained by ambulatory blood pressure monitoring and the carotid femoral pulse wave velocity, a widely used index of arterial distensibility, evaluated with Complior. We studied 64 young NF1 patients and 30 healthy subjects. There was no difference in pulse wave velocity between NF1 patients and healthy subjects. Ten of the NF1 patients showed 24-h SBP or 24-h diastolic blood pressure (DBP) >95th percentile for age and sex. We divided the NF1 group into subgroups: NF1 patients with 24-h SBP and 24-h DBP < or = 95th percentile for age and sex (NF1A group) and NF1 patients with mean SBP or DBP >95th percentile for age and sex (NF1B group). The pulse wave velocity of NF1A and NF1B patients were 6.3 +/- 1 m/sec and 6.4 +/- 1 m/sec, respectively (P = not significant). A significant relationship was found between 24-h SBP, 24-h heart rate, and pulse wave velocity in healthy subjects, but not in all NF1 patients and also between the NF1A and NF1B groups. Distensibility of the central arteries may be altered by various environmental or genetic factors. Thus, genetic determinants may play a role in the response of the large arteries to blood pressure. The recent discovery of neurofibromin in aortic smooth muscle may explain the vascular abnormalities present in NF1 patients. We emphasize the importance of a careful vascular evaluation using a noninvasive method, such as Complior and a periodic ambulatory blood pressure monitoring to detect NF1 patients at high risk of vascular complications.

Noninvasive evaluation of arterial abnormalities in young patients with neurofibromatosis type 1.

Neurofibromatosis regroups at least two different autosomal dominant genetic disorders: neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). Vascular disease is an underestimated complication of NF1. Few studies are available on this, all based on case reports. Neurofibromin, NF1 protein product, has also been detected in aortic smooth muscle. The purpose of this study was to evaluate the physical properties of the vessels, by measuring the carotid-femoral pulse wave velocity (PWV). This parameter was assessed by the Complior, a new noninvasive, validated device, used to screen a large population. The authors studied 64 neurofibromatosis patients (34 boys and 30 girls) with a mean age of 12 years (range 5-25 years). To investigate the presence of vascular lesions, aortic stiffness was evaluated by carotid-femoral PWV by using an automatic processor (Complior). They compared data from the PWV with a control group (30 healthy children, 17 boys and 13 girls, mean age 11 years, range 5-23 years). The calculated mean PWV in the control group was 6.5 +/- 1.15 m/s. The mean PWV of the 64 young patients with NF1 was 6.3 +/- 1.02 m/s. There was no difference between the two groups (p=0.39). Nevertheless, analysis of the linear regression has shown a linear relationship between systolic blood pressure (SBP) and PWV in the control group, while in NF1 patients this relationship is not present. The authors suggest that the coexistence of different factors, such as intimal proliferation, thinning media, fragmentation of the elastic tissue, irregularity, stenosis and tortuosity of the vessels, dysplasia of the small vessels, that counterbalance PWV, normalize the mean value. They emphasize the importance of a careful vascular evaluation, using noninvasive method, such as Complior. This device is well accepted by NF1 patients.

[Clinical value of multiplane transesophageal echocardiography in the diagnosis of lipomatous hypertrophy of the interatrial septum. Report of two clinical cases]. / Utilità clinica dell'ecocardiografia transesofagea multiplanare nella diagnosi di ipertrofia lipomatosa del setto interatriale. Descrizione di due casi clinici.

Lipomatous hypertrophy of interatrial septum is a very rare condition associated with supraventricular arrhythmias and sudden death. The authors describe two clinical cases of lipomatous hypertrophy and underline usefulness of multiplane transesophageal echocardiography in the diagnosis of this affection.

Mapping of Chlamydia trachomatis proteins by immobiline-polyacrylamide two-dimensional electrophoresis: spot identification by N-terminal sequencing and immunoblotting.

Proteins from purified elementary bodies of Chlamydia trachomatis were separated by two-dimensional gel electrophoresis on nonlinear wide-range immobilized pH gradients in the first dimension and polyacrylamide gradient gels in the second dimension. The maps obtained with this system are highly reproducible and resolve ca. 600 spots. By using immunoblot analysis with specific antibodies and/or N-terminal amino acid sequencing, we established the map positions of a number of described chlamydial proteins, such as the major outer membrane protein (MOMP) the 60 kDa cystein-rich outer membrane protein (OMP2), the DnaK-like, GroEL-like, and macrophage infectivity potentiator (MIP)-like proteins, the plasmid-encoded pgp3 protein, two ribosomal proteins (S1 and L7/L12), and the protein-elongation factor EF-Tu. Other proteins, for which gene assignment was not possible, have been identified by three parameters (Mr, pI and N-terminal sequence). This work provides a preliminary basis for a future and progressive compilation of a genome-linked database of chlamydial proteins.

Humoral immune response to plasmid protein pgp3 in patients with Chlamydia trachomatis infection.

We identified, by two-dimensional electrophoretic analysis and microsequencing, a protein of Chlamydia trachomatis elementary bodies which corresponds to the polypeptide (pgp3) encoded by open reading frame 3 (ORF3). Amino acid analysis showed that the first residue (Gly) found in the native protein is the one encoded by the second ORF3 codon, implying a typical bacterial removal of the first Met residue. Relatively large amounts of recombinant pgp3 (r-pgp3) in a stable, water-soluble form were obtained by overexpressing ORF3 in Escherichia coli and purifying the product from periplasmic extracts under nondenaturing conditions. These r-pgp3 preparations allowed specific detection of anti-pgp3 antibodies by enzyme-linked immunosorbent assay. Analysis of a group of 170 sera from healthy blood donors and from patients who were seropositive or -negative for C. trachomatis and Chlamydia pneumoniae showed that an immune response to pgp3 occurs in the majority (ca. 81%) of patients with sexually transmitted diseases who are seropositive for C. trachomatis and generally correlates with the response to cell surface antigens. No reaction between r-pgp3 and C. pneumoniae-positive sera was detected.

Expression of a plasmid gene of Chlamydia trachomatis encoding a novel 28 kDa antigen.

Plasmid pCT is present in essentially all isolates of Chlamydia trachomatis and may encode factors important for survival in the natural environment. However, no pCT-associated phenotype has been described so far. With the purpose of investigating the possibility of a role of pCT in C. trachomatis pathogenicity we examined the expression of an ORF (ORF3), potentially encoding a 28 kDa polypeptide (pgp3). Analysis of RNA extracted from chlamydia-infected Vero cells detected ORF3-specific transcripts, from 20 h post-infection onwards, mainly as discrete RNA species of 1390 nucleotides comprising the downstream ORF4 sequence. ORF3 DNA was cloned and expressed in Escherichia coli as a 39 kDa fusion protein (MS2/pgp3). Antibodies raised against purified MS2/pgp3, specifically recognized a 28 kDa protein on Western blots of protein from purified chlamydial elementary bodies (EBs). The same antibodies detected chlamydial inclusions in methanol-fixed infected cells by immunofluorescence. Western blot analysis of EBs extracted with 2% Sarkosyl, showed that a large proportion of the 28 kDa antigen is associated with the detergent-insoluble ('membrane') fraction. Antibodies recognizing pgp3 epitopes were detected in sera from patients with chlamydial infections, but not in sero-negative control sera. The finding support the hypothesis that pCT may provide a function related to chlamydial cell physiology.

Detection and typing of genital papillomaviruses in men with a single polymerase chain reaction and type-specific DNA probes.

BACKGROUND: Human papillomavirus (HPV) infection of the genitalia can produce both visible and subclinical lesions. Because different genotypes are preferentially associated with benign or malignant lesions, HPV detection and typing is clinically important. OBJECTIVE: Our purpose was to assess a polymerase chain reaction (PCR)-based, noninvasive procedure for HPV diagnosis and evaluate the reliability of the acetic acid test for revealing subclinical HPV lesions. METHODS: Mucosal samples were collected by gentle scraping, and PCR-positive samples were typed by hybridization with specific DNA probes. RESULTS: Seventy-eight men were assessed. The PCR procedure was reliable and easy to perform. No significant difference was found in the prevalence of HPV infection between patients whose results were acetowhite-positive and those whose results were acetowhite-negative. CONCLUSION: Detection of acetowhite epithelium, although useful for clinical examination, is not sufficiently specific and should not be used as a sole criterion for the diagnosis of HPV infection.

Transcriptional analysis of the Chlamydia trachomatis plasmid pCT identifies temporally regulated transcripts, anti-sense RNA and sigma 70-selected promoters.

We analysed transcription of the DNA region immediately downstream of the origin of replication in the chlamydial plasmid pCT. This region comprises two convergent open reading frames (ORF7, ORF8), encoding putative polypeptides that are homologous to each other and with C-terminal domains typical of the phage integrase family of proteins. Northern blot and RNA 5' end mapping analyses indicated that both ORFs were transcribed in the late phase of the chlamydial replicative cycle. RNA mapping showed the presence of a transcript starting 31 nucleotides (nt) before the ATG start codon of ORF7, and two temporally regulated transcripts starting 59 and 89 nt upstream of the ATG start codon of ORF8. Two abundant RNA species of 225 and 415 nt were also identified as overlapping anti-sense transcripts (AS-RNAs), complementary to the 3' end of ORF8 mRNA, with identical 5' ends but different 3' ends. In vitro and in vivo experiments in Escherichia coli showed that the sigma 70-RNA polymerase complex was capable of initiating RNA synthesis at the same sites as observed in Chlamydia trachomatis for ORF7 and AS-RNA transcripts, but was not able to transcribe ORF8. In accord with this, sequences at -10 and -35 nt upstream of the RNA 5' ends resemble sigma 70 consensus promoters in the case of ORF7 and AS, but not in the case of the two ORF8 transcripts. Therefore, transcription of ORF7 and ORF8 is controlled by different types of promoters.(ABSTRACT TRUNCATED AT 250 WORDS)

Development of transplantable ascites tumours which continuously produce polyclonal antibodies in pristane primed BALB/c mice immunized with bacterial antigens and complete Freund's adjuvant.

Bacterial immunogens (whole cells of Borrelia burgdorferi, elementary bodies of Chlamydia trachomatis and purified proteins of 22 and 24 kDa of Borrelia hermsii) were emulsified with an excess of complete Freund's adjuvant and injected (i.p.) on days 0, 7, 14 and 21, into BALB/c mice treated with pristane on day 6. This procedure induced the development of antibody-producing ascites tumours which could be serially transplanted in pristane-conditioned mice. Ascites tumours continued to yield a consistent amount of specific polyclonal antibody after ten serial transplants. The method described appears to be particularly useful for the production of a large amount of antibody when only small amounts of immunogen are available.

Diversity of the Chlamydia trachomatis common plasmid in biovars with different pathogenicity.

The 7.5-kb plasmid of Chlamydia trachomatis (CT) is believed to encode essential genes and might have a role in CT pathogenicity. Accordingly, analysis of plasmid-linked mutations in isolates from biovars with different pathogenic properties should help in identifying which plasmid-encoded genes, if any, may be involved in modulating virulence. For this purpose, the plasmid present in a low-virulence isolate (trachoma biovar, serotype D) was cloned and sequenced. Nucleotide changes were experimentally checked against the sequence of the plasmid variant from the highly virulent strain L2/434/Bu (LGV biovar). By aligning our data with two published sequences of different trachoma and LGV variants a general consensus structure was determined, comprising eight major open reading frames (ORF) and a number of points where there is consensus only between isolates of the same biovar (biovar-specific mutations). The degree of variation between different isolates is less than 1%. In particular, comparison of serotype-D and -L2 plasmids shows mutations which are generally silent or lead to few (one to four), often conservative, amino acid changes in ORFs 1, 2, 4, 5, 6, and 7. The protein encoded by ORF8 is completely conserved. In contrast, the polypeptide variants encoded by ORF3 show nine amino acid changes, seven of which are due to biovar-specific mutations.

Detection and typing of human papillomavirus in histologic specimens by in situ hybridization with biotinylated DNA probes.

Eighty tissue biopsies from 73 women suspected of having papillomavirus (HPV) infection of the lower genital tract were examined by in situ hybridization with biotinylated DNA probes derived from the complete genomes of four HPV types (6, 11, 16, and 18) and restriction analysis of the extracted DNA on Southern blots. In a subset of 52 samples, the in situ test had a 90.4% sensitivity (47 of 52) in detecting the presence or absence of virus, whereas Southern blot analysis detected HPV with a sensitivity of 98.1% (51 of 52). For 51 samples, in which the viral type was determined by restriction analysis, comparison of the signals separately generated by the four probes after in situ hybridization allowed a correct identification of the infecting HPV type in 86.2% (44 of 51) of cases.

The structure of a plasmid of Chlamydia trachomatis believed to be required for growth within mammalian cells.

Sequence analysis of a 7.5 kb DNA plasmid isolated from Chlamydia trachomatis shows 8 open reading frames (ORFs) regularly spaced along most of the sequence. One of these ORFs encodes a 451-amino-acid polypeptide highly homologous to the DnaB protein of Escherichia coli. A region between ORFs 6 and 7 contains a cluster of alternating ATs and a 22 bp sequence tandemly repeated 4 times, suggesting a replication control region. Several ORFs correspond to plasmid-specific polypeptides that have been described. Codons ending with A or T are more frequent, as might be expected from the high A/T content (64%) of the plasmid, and codon usage is similar to that of the C. trachomatis chromosomal gene, omp1L2.

[Defibrotide in the prevention of deep venous thrombosis in general surgery. Preliminary results of a multicenter study]. / Defibrotide nella prevenzione delle trombosi venose profonde in chirurgia generale. Risultati preliminari di uno studio multicentrico.

In an open multicenter comparative study aimed at the evaluation of the efficacy of defibrotide in the prophylaxis of postsurgical deep vein thromboses (DVT) an ad interim evaluation has been made on 2626 patients thus far enrolled. 1323 had received defibrotide (200 mg q.i.d. by IV route from day -1 to day +7th postoperative), 941 calcium heparin (5000 IU b.i.d. or t.i.d. by SC route from day 0 to day +7 postoperative) and 362 other treatments (antiaggregating agents, placebo or no therapy). This group has not been included in the final evaluation, due to its limited size. The diagnosis of DVT or pulmonary embolism (PE) was made according to clinical routinary criteria. The incidence of DTV has been 15/1323 (1.13%) in the defibrotide group and 21/941 (2.23%) in the heparin group (chi-square, p = 0.056) while the cases of suspected or ascertained PE have been respectively 3/1323 (0.22%) and 10/941 (1.06%) (p = 0.02). The incidence of adverse effects with defibrotide was less than 1%; occasional cases of increased serum transaminase levels were seen with heparin. These preliminary results supports the effectiveness of defibrotide in the prevention of post-surgery DVT, its effects being similar or more prominent than those of calcium heparin, currently regarded as the standard medication.

[Prevention of thromboembolism in patients operated on for hip prosthesis]. / La prevenzione delle tromboembolie negli operati di artroprotesi d'anca.

The latest research into the prevention of peri- and postoperative thromboembolic disease has found orthopaedic surgery patients to be most at risk. As the genesis of deep venous thrombosis (DVT) is due to haemodynamic, hemorheologic and parietal factors, various prophylactic measures have been considered in the past, measures which have not proved able to provide satisfactory protection in orthopaedics. The results obtained with Defibrotide in a random and controlled clinical study versus calcium heparin involving 211 patients of both sexes candidates to receive total hip arthroplasty and presenting at least one major thromboembolic risk factor are reported. The patients were assigned at random to one of the following treatments: 1) Defibrotide at a dose of 400 mg b.i.d. i.v. in 50 ml phleboclysis in 5 minutes (n = 108); 2) calcium heparin at a dose of 5000 IU t.i.d. subcutaneously (n = 103). The treatment began the day before operation and continued on average up to the eighth day for the Defibrotide group. With the control group it continued until discharge (usually on the 15th day) and at home for about three weeks until the completion of the physiotherapy cycle. In the 108 patients treated with Defibrotide only one case of DVT was reported and in none of these patients were symptoms or signs of pulmonary embolism encountered. In the group treated with calcium heparin 2 cases of clinically and radiologically diagnosed pulmonary embolism and 4 cases of DVT were observed. Although the differences were not statistically significant, the tendency favours Defibrotide. Statistically significant (p less than 0.01) was the difference in postoperative bleeding evaluated with particular attention in patients of advanced age. Further, in the Defibrotide group, scarring was considered excellent in 96% of cases while in the heparin group scarring was excellent in 85% (p less than 0.05). To conclude, the sure clinical effectiveness, tolerance, handiness and lack of interference with clotting functions make Defibrotide a really useful drug for the prevention of thromboembolic episodes in patients undergoing major orthopaedic surgery.

[Prevention of deep venous thrombosis with defibrotide in chest surgery. Controlled multicenter study versus heparin]. / Profilassi con defibrotide delle trombosi venose profonde in chirurgia toracica. Studio multicentrico controllato verso eparina.

The effectiveness and tolerability of defibrotide in the prevention of post-surgery deep vein thrombosis (DVT) were compared with those of heparin in a multicentric randomized controlled study. One hundred-eight-four both sexes patients submitted to thoracic surgery were randomly allocated to defibrotide (400 mg b.i.d. by IV route, n = 94) or to calcium heparin (5000 I.U. t.i.d. s.c., n = 90); both treatments were started the day before the operation and withdrawn when patients were allowed to stand up (i.e., after 7 days). No patients developed DVT in the defibrotide group, while a single case of DVT was detected in the heparin group; furthermore, a more prominent bleeding was observed in the latter, in the early post-operative period (normal bleeding: 2nd day: defibrotide 70/92 pts, heparin 53/90 pts, p less than 0.02; 3rd day: defibrotide 87/92 pts, heparin 76/90 pts, p less than 0.05, chi 2 test), while the healing rate of surgical wounds was similar in the two groups. No relevant modifications in laboratory parameters were seen throughout the observation period. Thus, these preliminary data suggest that defibrotide is at least as effective as heparin in the prevention of post-thoracic surgery DVT and that the former drug has a possibly better tolerability profile, due to a lesser tendency to bleeding.