Changes in myocardial pyrimidine nucleotide levels following repeated injections of isoproterenol in rats

Changes which might lead to the initiation of cardiac hypertrophy include possible variations in the dynamics of nucleotides. In the experiments reported in this paper, changes in the pool sizes of adenine, uracil and cytosine nucleotides were observed during the initial phase of cardiac overload.Repeated subcutaneous injections of isoproterenol (ISO) (5 mg·kg^–1 body weight, s.c.) were performed so as to produce symmetric cardiomegaly in rats. Under these conditions, the dry weight of the heart, on the fifth day of dialy injections of ISO, had increased by 43% and the RNA concentration by 39%. There was no significant change in the DNA concentration. No further changes in weight or in DNA and RNA concentrations were recorded from the fifth to the tenth day of treatment.Changes in UTP and ATP were carefully monitored during the first days following ISO application. The levels of both nucleotides decreased sharply at first. The ATP level remained below the control value for at least 48 h while the UTP level was rapidly restored and a further increase occurred resulting in a maximal enlargement of 82% after the 12th h. At the same time, the uracil nucleotide pool and the cytosine nucleotide pool had increased by 76% and 101%, respectively, while the adenine nucleotide content of the myocardium remained 15% below control level. Repeated injections of ISO induced effects on ATP and UTP levels which were similar in direction but attenuated.The significance of an increase in the pyrimidine nucleotide pools in relation to nucleic acid synthesis is discussed.     

Peritoneal fluid concentrations of interleukin-8 in women with endometriosis: relationship to stage of disease

There is increasing evidence that immunological mechanisms play a role in the pathogenesis and pathophysiology of endometriosis. It was therefore of interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal fluid and peripheral blood of women undergoing laparoscopic procedures. The presence and concentrations of IL-8 in relation to endometriosis, infertility and abdominal pain were evaluated. Samples of peritoneal fluid (n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive patients undergoing laparoscopic surgery for various gynaecological indications (abdominal pain, infertility, sterilization). IL-8 was present in the peritoneal fluid of most women (87%). The concentration of IL-8 in the peritoneal fluid was higher in women with endometriosis compared to women without (P = 0.02). This difference was more pronounced in early (stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal fluid were also higher in women with early endometriosis compared to women with later stages of the disease (P = 0.003). Peripheral blood concentrations did not correlate with peritoneal fluid concentrations of IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an important factor that may contribute to the pathogenesis of endometriosis possibly by promoting neovascularization. This information can be a guide in the development of new therapeutic approaches for the treatment of endometriosis.      

Genotype-phenotype relationship in human ATP6i-dependent autosomal recessive osteopetrosis

Autosomal-recessive osteopetrosis is a severe genetic disease caused by osteoclast failure. Approximately 50% of the patients harbor mutations of the ATP6i gene, encoding for the osteoclast-specific a3 subunit of V-ATPase. We found inactivating ATP6i mutations in four patients, and three of these were novel. Patients shared macrocephaly, growth retardation and optic nerve alteration, osteosclerotic and endobone patterns, and high alkaline phosphatase and parathyroid hormone levels. Bone biopsies revealed primary spongiosa lined with active osteoblasts and high numbers of tartrate-resistant acid phosphatase (TRAP)-positive, a3 subunit-negative, morphologically unremarkable osteoclasts, some of which located in shallow Howship lacunae. Scarce hematopoietic cells and abundant fibrous tissue containing TRAP-positive putative osteoclast precursors were noted. In vitro osteoclasts were a3-negative, morphologically normal, with prominent clear zones and actin rings, and TRAP activity more elevated than in control patients. Podosomes, alphaVbeta3 receptor, c-Src, and PYK2 were unremarkable. Consistent with the finding in the bone biopsies, these cells excavated pits faintly stained with toluidine blue, indicating inefficient bone resorption. Bone marrow transplantation was successful in all patients, and posttransplant osteoclasts showed rescue of a3 subunit immunoreactivity.     

BCL-2 in primary central nervous system lymphomas. Immunohistochemistry and molecular biology

BCL-2 is a membrane protein known to be an apoptosis inhibitor. It is the product of the bcl-2 gene located on chromosome 18. Several different tumors show BCL-2 over-expression as result of a translocation or independently from it. More than 85% of follicular lymphomas and a smaller number of diffuse large cell B lymphomas contain t(14;18) (q32;q21). The aim of this study was to investigate the immunohistochemical expression of the BCL-2 protein and to ascertain, by means of traditional PCR (Polimerase Chain Reaction), its possible dependence from t(14;18) (q32;q21) in 9 primary central nervous system lymphomas. Six cases (67%) shoved immunohistochemical BCL-2 over-expression and 3 cases (33%) had t(14;18). Precisely: 2 cases (22%) had immunohistochemical BCL-2 over-expression and t(14;18) (q32;q21); 4 cases (44%) had BCL-2 over-expression without translocation; 1 case (11%) did not show diffuse BCL-2 over-expression in presence of the traslocation; the remaining 2 cases (22%) did not demonstrate BCL-2 over-expression or t(14;18) (q32;q21). In conclusion, our results indicate primary central nervous system lymphomas frequently show BCL-2 over-expression that in some case may be related to t(14;18) (q32;q21). Nevertheless, t(14;18) (q32;q21), as evaluated by traditional PCR, may not correspond to diffuse immunohistochemical BCL-2 positivity.     

Anti-idiotypes against autoantibodies and alloantibodies to VIII:C (anti-haemophilic factor) are present in therapeutic polyspecific normal immunoglobulins.

Therapeutic, polyspecific, normal immunoglobulins (IVIg) suppress anti-factor VIII (VIII:C) activity of anti-VIII:c autoantibodies in vivo and in vitro. In the present study anti-VIII:C activity was found to be inhibited by two different preparations of IVIg in the plasma of three of four patients with autoantibodies and two of three patients with alloantibodies. F(ab')2 fragments from IVIg inhibited anti-VIII:C activity in F(ab')2 fragments from the plasma of the patients. In patients in whom anti-VIII:C activity was inhibited by IVIg, anti-VIII:C F(ab')2 antibodies were specifically retained on an affinity column of Sepharose-bound F(ab')2 from IVIg. In patients in whom anti-VIII:C activity was not suppressed by IVIg in vitro, no binding of anti-VIII:C antibodies to Sepharose-bound IVIg was observed. In a patient in whom anti-VIII:C activity was only suppressed by one preparation of IVIg, specific binding of anti-VIII:C antibodies was only observed with that preparation but not with another. These results indicate that IVIg contain anti-idiotypes against autoantibodies and alloantibodies to VIII:C. The capacity of IVIg to inhibit anti-VIII:C activity in vitro is directly related to the presence of demonstrable anti-idiotypes against anti-VIII:C antibodies. The finding of anti-idiotypes against anti-VIII:C alloantibodies in IVIg suggests that, in addition to autoantibodies, some alloantibodies may be suppressed in vivo by IVIg.     

Effects of sildenafil (Viagra) administration on seminal parameters and post-ejaculatory refractory time in normal males

Sildenafil is a specific inhibitor of phosphodiesterase (PDE) type 5 and represents a powerful therapy for male erectile dysfunction (ED) of different aetiology. Recently, sildenafil has been shown to restore erections in temporary ED related to the need of semen collection for assisted reproductive techniques. In this study, we investigated whether sildenafil administration modifies seminal parameters and/or erectile function in normal healthy volunteers. In a double-blind, randomized, placebo-controlled, cross-over two period investigation we enrolled 20 healthy male volunteers (mean +/- SE age 32 +/- 0.5 years). Subjects were not using any medication for the 3 month period prior to the study and were engaged in a stable relationship with proven fertility. The effects of sildenafil (100 mg) on seminal parameters and erectile function after audiovisual sexual stimulation were evaluated by semen analysis and by colour-Duplex ultrasound (the Resistive Index) respectively. In all subjects, sildenafil caused no changes in seminal and erection parameters when compared to placebo. Interestingly, sildenafil administration led to a marked reduction of the post-ejaculatory refractory time (10.8 +/- 0.9 min versus 2.6 +/- 0.7 min for placebo and sildenafil respectively; P < 0.0001). These results indicate that in normal subjects acute sildenafil treatment does not modify semen characteristics and has a positive influence over the resumption of erections following ejaculation in the presence of a continuous erotic stimulus.     

A PCR-colorimetric microwell plate hybridization assay for detection of Mycobacterium tuberculosis and M. avium from culture samples and Ziehl-Neelsen-positive smears

Differentiation between Mycobacterium tuberculosis and M. avium is essential for the treatment of mycobacterial infections. We have developed an easy and rapid detection assay for the diagnosis of mycobacterial diseases. This is a PCR-hybridization assay based on selective amplification of a 16S rRNA gene sequence using pan-Mycobacterium primers followed by hybridization of the amplification products to biotinylated M. tuberculosis and M. avium-specific probes. A total of 55 mycobacterial isolates were tested. For all isolates, results concordant with those of conventional identification methods were obtained. Moreover, we developed a method for extraction of DNA from Ziehl-Neelsen-positive smears which allows the recovery of intact target DNA in our PCR-hybridization assay. Our method was able to confirm all culture results for 59 Ziehl-Neelsen-positive smears from clinical specimens (35 sputum, 11 lymph node biopsy, 6 stool, 4 pus, 2 urine, and 1 pericardial fluid specimens). These data suggest that our PCR-hybridization assay, which is simple to perform and less expensive than commercial probe methods, may be suitable for the identification of M. tuberculosis and M. avium. It could become a valuable alternative approach for the diagnosis of mycobacterial infections when applied directly to DNA extracted from Ziehl-Neelsen-positive smears as well.     

Recurrent "Flexispira rappini" bacteremia in an adult patient undergoing hemodialysis: case report

A blood culture from a 65-year-old febrile man undergoing hemodialysis revealed, 5 days after inoculation, an unusual gram-negative fusiform rod with darting motility. During another episode of fever 21 days later, this Campylobacter-like organism was again recovered from three blood cultures and subcultured under an H2-enriched microaerobic atmosphere. The organism was catalase negative and oxidase positive and hydrolyzed urea rapidly. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of whole-cell proteins was indistinguishable from that of "Flexispira rappini" LMG 8738 described by Archer et al. in 1988 (J. R. Archer, S. Romero, A. E. Ritchier, M. E. Hamacher, B. M. Steiner, J. H. Bryner, and R. F. Schell, J. Clin. Microbiol. 26:101-105, 1988). The analysis of the 16S ribosomal DNA sequence revealed a similarity of 99.3% between the two strains. The patient recovered completely after a 4-week course of meropenem therapy. This is the first reported case of a recurrent "F. rappini" bacteremia in an adult patient, which confirms that this organism may be an invasive pathogen in immunocompromised patients, like other newly described Helicobacter species.