Platelet aggregation and aspirin non-responsiveness increase when an acute coronary syndrome is complicated by an infection.

BACKGROUND: Epidemiologic studies have shown that there is an association between acute respiratory infection and acute coronary syndrome. The aim of this study was to analyze the thrombotic risk, assessed by platelet aggregation and aspirin non-responsiveness, in patients with an acute coronary syndrome complicated by an infection. METHODS: Patients with an acute coronary syndrome who were admitted to the intensive care unit and hospitalized for at least 3 days in 2002 and 2003 were eligible for the study. Three hundred and fifty-eight patients were included, of whom 66 had an infection during their hospital stay. Platelet aggregation was analyzed by an aggregometer using laser light (PA-200, laser light scattering). Aspirin non-responsiveness was defined as a closure time of

Expression of cGMP-binding cGMP-specific phosphodiesterase (PDE5) in mouse tissues and cell lines using an antibody against the enzyme amino-terminal domain.

We have produced a polyclonal antibody that specifically recognizes cGMP-binding cGMP-specific phosphodiesterase (PDE5). The antibody was raised in rabbit using as immunogen a fusion protein, in which glutathione S-transferase was coupled to a 171 amino acid polypeptide of the N-terminal region of bovine PDE5. The antibody is able to immunoprecipitate PDE5 activity from mouse tissues and neuroblastoma extracts while it has no effect on all other PDE isoforms present in the extracts. PDE5 activity recovered in the immunoprecipitates retains its sensitivity to specific inhibitors such as zaprinast (IC(50)=0.6 microM) and sildenafil (IC(50)=3.5 nM). Bands of the expected molecular mass were revealed when solubilized immunoprecipitates were analysed in Western blots. The antibody selectively stained cerebellar Purkinje neurones, which are known to express high levels of PDE5 mRNA. Western blot analysis of mouse tissues revealed the highest expression signal in mouse lung, followed by heart and cerebellum, while a lower signal was evident in brain, kidney and a very low signal was present in the liver. In the hybrid neuroblastoma-glioma NG108-15 cells the antibody revealed a high PDE5 induction after dibutyryl-cAMP treatment.

Transduction of genes coding for a histocompatibility (MHC) antigen and for its physiological inducer interferon-gamma in the same cell: efficient MHC expression and inhibition of tumor and metastasis growth.

The mouse mammary carcinoma TS/A, of BALB/c (H-2d) origin, was transfected with the murine interferon-gamma (IFN-gamma) gene (Int. J. Cancer 55: 320, 1993). We used IFN-gamma transfectants as recipients for a second round of transfections with murine allogeneic class I histocompatibility (H-2b) genes that are modulated by IFN. Transfectants with either gene alone, as well as parent TS/A cells (TS/A-pc), were used as controls. Only double transfectants expressed high levels of the allogeneic H-2b genes, while in H-2b single transfectants the expression was very low (but was induced by treatment with exogenous IFN-gamma). The tumorigenic potential of IFN-gamma or H-2b single transfectants was reduced in comparison to TS/A-pc. IFN-gamma+H-2Kb double transfectants were almost nontumorigenic, while IFN-gamma+H-2Db clones gave rise to tumors in about one-half of mice. The experimental metastatic ability of all IFN-gamma+H-2b double transfectants was very low. IFN-gamma single transfectants were known to induce a strong macrophage response in the host. The expression of allogeneic H-2 antigens added a T-lymphocyte-mediated response that accounted for the lower tumorigenicity of double transfectants. These results show that it is possible to steer the immune response evoked by tumor cells for therapeutic purposes. Moreover, the high H-2 expression obtained in IFN-gamma+H-2b double transfectants suggests that single IFN-gamma transfectants are ideal recipients for all IFN-sensitive genes. This approach can be used also for other general-purpose inducers of gene expression.

Cure of mice with established metastatic friend leukemia cell tumors by a combined therapy with tumor cells expressing both interferon-alpha 1 and herpes simplex thymidine kinase followed by ganciclovir.

Transduction of the murine interferon-alpha (IFN-alpha) gene into various malignant mouse tumor cells has resulted in the loss of tumorigenicity and an acquired capacity to induce long-lasting antitumor immunity following their injection into immunocompetent syngeneic mice. In the present study, we investigated the effectiveness of IFN-alpha-producing tumor cells in the therapy of mice with established mouse tumors. In DBA/2 mice bearing subcutaneous (s.c.) Friend erythroleukemia cell (FLC) tumors, we found that to achieve some antitumor response (i) it was necessary to inject high numbers of IFN-alpha-producing FLC, which occasionally lead to the formation of slowly growing tumors; and, that (ii) repeated injections of irradiated IFN-alpha-FLC did not result in any antitumor effect. The therapeutic potential of IFN-alpha-producing FLC rendered sensitive to ganciclovir (GCV), by transfer of the herpes simplex virus thymidine kinase (tk) gene, was investigated. Complete tumor rejection and cure was observed in > or = 70% of the animals after injection of high numbers (10(7)) of IFN-alpha-producing tk-expressing tumor cells followed 4 days later by repeated GCV treatments, whereas only a slight increase in survival time was obtained after administration of control tk-expressing tumor cells (not producing IFN) and GCV. Tumor rejection was associated with a dramatic destruction of tumor tissue and with the subsequent development of a potent and long-lasting antitumor immunity. No therapeutic effect was observed in immunosuppressed nude mice. These data indicate that this approach may represent an effective and safe therapeutic strategy for antitumor cytokine gene therapy.

Retinoic acid negatively regulates beta 4 integrin expression and suppresses the malignant phenotype in a Lewis lung carcinoma cell line.

Retinoic acid (RA) is a potent inhibitor of the malignant phenotype and of tumour cell growth. We observed that in vitro RA treatment of a highly metastatic lung carcinoma cell line (C87) induced a marked reduction in the amount of the beta 4 integrin subunit. The downregulation of this adhesion molecule was assessed by immunofluorescence, immunoprecipitation, and northern analysis. In order to investigate the effects of RA on the malignant phenotype in C87 cells we performed morphological and functional analysis after RA treatment. We found that RA was able to produce marked changes in C87 cell shape, increasing the number of flat cells (90% of the total cell population), and significantly inhibiting the malignant and invasive phenotype of C87 cells. RA treatment suppressed their clonogenic potential in soft agar (control, 20 +/- 5; RA, 0), and strongly reduced their chemotactic and chemoinvasive capacity (chemotaxis: control, 231 +/- 5; RA, 28 +/- 0; chemoinvasion: control, 132 +/- 11; RA = 2 +/- 1). FACS analysis and cell count, however, indicated that RA reduced the growth of C87 cells only partially. After 72 h of treatment we observed only a 10% reduction in the S phase fraction of the cell population. Finally, the reduced lung colony-forming ability, observed after i.v. injection of RA-treated cells (lung foci/animal: RA-treated cells, 1 +/- 0.1; untreated, 8.5 +/- 0.8), further supports the conclusion that in this murine lung carcinoma cell line a marked reduction in the expression of the beta 4 integrin subunit is associated with a marked inhibition of the malignant phenotype.

F-wave study in patients with chronic renal failure on regular haemodialysis.

Motor nerve conduction along the entire length of ulnar and tibialis posterior nerves was studied in 30 uraemic patients and in 20 control subjects. The M and F latencies, MNCV (between the stimulus sites), FWCV (between the spinal cord and the stimulus sites) and F-ratio (conduction time ratio of proximal to distal segment) were assessed to evaluate the conduction in the proximal versus the distal nerve segment. In the uraemic patients, the slowing of nerve conduction involved both segments of the tested nerves to the same extent. In fact, the F-ratio did not show any significant difference between the two groups; in only one patient was its value lower than the normal limit in the tibialis posterior nerve.

Ultrastructural and immunohistochemical characterization of the tunica albuginea in Peyronie's disease and veno-occlusive dysfunction.

The tunica albuginea and corpus cavernosum from patients with Peyronie's disease (PD), patients with veno-occlusive dysfunction (VOD), and those from normal control subjects were studied by transmission electron microscopy and immunohistochemical staining for type I, III, and V collagens, platelet-derived growth factor (PDGF) AA and BB homodimers, and PDGF alpha and beta receptors. Ultrastructural modifications resembling a fibrotic reaction were detected in the two pathological tunica albuginea, but not in those from control subjects. Ultrastructural data demonstrated a general increase in fibrous and amorphous extracellular matrix material in the pathological tunica albuginea. The amorphous material probably represents glycoproteins and proteoglycans. The fibrous material, representing collagen, appears disorganized in the tissue and does not display the typical and homogeneous diameter, size, and spatial arrangement. Large areas of extracellular and intracytoplasmic, partially degraded, fibers are visible. An increased type I/III collagen ratio was detected by immunohistochemistry in the two pathological tunica albuginea. Moreover, a strong expression of type V collagen, correlated to fibroblasts, was revealed. Fibroblasts from control tissues, on the other hand, were totally negative. Finally, PDGF AA and BB were positive in fibroblasts from pathological tunica albuginea but were negative in control tissues. PDGF beta receptor was positive in pathological and normal tissue fibroblasts. Tunica albuginea from PD and VOD show similar ultrastructural and immunohistochemical alterations, whereas the corpus cavemosum shows no visible modifications.

Heavy metal toxicity following apical and basolateral exposure in the human intestinal cell line Caco-2.

Caco-2 is a cell line, derived from a human colon carcinoma, that retains the ability to differentiate in culture into absorptive intestinal cells. Caco-2 cells were used to evaluate the toxicity of three heavy metals-the essential trace elements zinc and copper, and the xenobiotic cadmium. The cells were cultivated on permeable filters until differentiated and were then exposed to the metals either from the apical (luminal) or from the basolateral (serosal) side. Toxicity was measured in dose-effect experiments with reference to cell survival and integrity of the cell monolayer. The metals were more toxic when presented to the basolateral than to the apical cell side. The toxicity ranking was cadmium > > copper > zinc. The cell's ability to transport each metal across the monolayer and the resulting intracellular accumulation could account for the cytotoxic effects. A specific toxic effect observed on a specialized function of these cells was the interference of cadmium in tight-junction integrity as shown by changes in the transepithelial electrical resistance, in the rate of transport of a specific marker across the cell monolayer, and by morphological alterations of the tight junctions.

[Prostaglandins and peptic ulcer disease]. / Prostaglandine e malattia ulcerosa.

The action of prostaglandins with regard to ulcers is made clear by their inhibition of gastric secretion, on the one hand, and their so-called cytoprotective effect, on the other. Experimental data are used in a summary of the explanations offered of the mechanisms underlying these two effects. In addition, attentions is directed to the possible rôle of the prostaglandins in gastric physiology, and hence in the physiopathology of ulcers. The therapeutic results obtained with prostaglandins in the management of gastroduodenal ulcer offer firm grounds for supposing that further developments will take place in the clinical field.

[Audio-vestibular changes in patients with rheumatoid arthritis]. / Alterazioni audio-vestibolari in soggetti con artrite reumatoide.

A functional audio-vestibular investigation based on impedance metric techniques and electronystagmography was carried out in a group of patients with "classical" rheumatoid arthritis (RA) and with treated or untreated "definite" RA in various stages. Data obtained from these patients were compared with those obtained from a control group. Significant hypoacusis of the transmissive type was found in initial stages of RA while sensorineural or mixed type hypoacusis was found in later stages of RA. Significant vestibular alterations of the central type suggesting supratentorial involvement were found in several cases independently of the stage of RA and of the age of the patients.

F-response assessment in healthy control subjects.

Various parameters of the F-response (latencies, chronodispersion, amplitude, duration, shape, persistence) were investigated in ulnar and tibial nerves of 50 healthy subjects of both sexes, aged between 16 to 79 years. The observations were made bilaterally and the results revealed no significant differences in any of the F-parameters by comparing side to side. The relationships between each neurophysiological F-response data and limb length, age and sex of control subjects were determined. Correlations of high statistical significance were found between minimum F-latency and limb length as well as between absolute and F%/M-amplitude and age. Cross-correlation coefficients correlating mean individual values of latency-duration, latency-amplitude and amplitude-duration did not show any significant relationship between latency, amplitude and duration in normal subjects.

F-wave study at different stimulation rates.

In 50 ulnar nerves of healthy subjects, F-wave latency, duration, amplitude and persistence were determined at different frequencies of the antidromic impulse (0.2-0.5-1-2 Hz). The F amplitude and persistence were found significantly increased at higher stimulation rates, suggesting that the frequency of the antidromic impulse influences the motoneuron pool discharges. Individual cross-correlation values (r) obtained for latency and duration, latency and amplitude, amplitude and duration did not show any significant changes at different stimulation rates.

F-wave study at different stimulation rates in upper motoneurone lesions.

F-wave duration, amplitude and persistence at different frequencies of the antidromic impulse (0.2-0.5-1-2 Hz) were determined in 18 patients with vascular hemiplegia and in 32 healthy subjects of both sexes in the same age range. In normal subjects F amplitude and persistence showed a significant increase as the stimulation rate increased; in spastic patients a small difference in F amplitude was only found for greater difference in stimulus frequencies, the persistence did not significantly changed at different stimulation rates. Individual cross-correlation values (r) obtained for latency and duration, latency and amplitude, amplitude and duration did not show significant changes at different stimulation rates in patients and in controls.

[A histological and ultrastructural study of the effects of the argon laser scalpel on the kidney]. / Studio istologico ed ultrastrutturale degli effetti del bisturi laser ad argon sul rene.

The authors carried an histological and ultrastructural study on rat kidney following polar excision by argon laser. The involvement of the remainder portion of the kidney was evaluated analysing the depth of the damage induced by the laser radiation. Restitution ad integrum was found below 360 micron thickness with a different involvement of the various kidney components. Glomeruli showed a deep damage caused by intravascular photocoagulation. On the contrary, tubular and extracellular damage was less serious and the damaged area extended for only 240 micron from the section, probably for a lack of absorbance of the argon radiation by clear and water-rich tissues.

[Prognostic significance of desmoplasia in breast carcinoma. A preliminary clinical study]. / Significato prognostico della desmoplasia nel carcinoma della mammella. Studio clinico preliminare.

This study carried on 61 patients with breast cancer confirmed the biological assumption of a higher malignancy in tumors with strong desmoplastic reaction. Patients in stage II A, II B and III presenting a marked desmoplastic reaction have a shorter DFS (disease free survival). Therefore, desmoplastic reaction may be considered a marker of local malignancy and metastatic process.

[The biological effects of the CO2 laser studied in experimental intestinal resections]. / Studio degli effetti biologici del laser CO2 nelle resezioni intestinali sperimentali.

An histological and E.M. study has been performed on rat's intestinal tract resection to evaluate CO2 laser effects. Necrotic effect of laser is evident up to 120 micron. While the intestinal tissue results normal at 480 micron from resection line. Muscular and fibrous components appear more resistant to damage while E.M. presents a new organization of its components forming a new compact and continue tissue. This new organization may be involved in the protection of the subepithelial spaces, and may have an important role in intestinal anastomosis scar process.

Thymectomy and multiple sclerosis: ultrastructural study of an experimental model.

Transmission electron microscopy was performed on specimens of the thymus of rats induced for acute experimental allergic encephalomyelitis (EAE). The ultrastructural alterations of the thymus were progressive and correlated with EAE development. The thymic disorganization was due to a progressive degeneration of both epithelial cells and thymocytes. These data suggest a direct involvement of the epithelial thymic cells and thymocytes in EAE pathogenesis and may suggest the intriguing therapeutic concept of thymectomy in the management of multiple sclerosis.