Interactions between NO, CO and an endothelium-derived hyperpolarizing factor (EDHF) in maintaining patency of the ductus arteriosus in the mouse.

BACKGROUND AND PURPOSE: Prenatal patency of ductus arteriosus is maintained by prostaglandin (PG) E(2), possibly along with nitric oxide (NO) and carbon monoxide (CO), and cyclooxygenase (COX) deletion upregulates NO. Here, we have examined enzyme source and action of NO for ductus patency and whether NO and CO are upregulated by deletion of, respectively, heme oxygenase 2 (HO-2) and COX1 or COX2. EXPERIMENTAL APPROACH: Experiments were performed in vitro and in vivo with wild-type and gene-deleted, near-term mouse fetuses. KEY RESULTS: N(G)-nitro-L-arginine methyl ester (L-NAME) contracted the isolated ductus and its effect was reduced by eNOS, but not iNOS, deletion. L-NAME contraction was not modified by HO-2 deletion. Zinc protoporphyrin (ZnPP) also contracted the ductus, an action unaffected by deletion of either COX isoform. Bradykinin (BK) relaxed indomethacin-contracted ductus similarly in wild-type and eNOS-/- or iNOS-/-. BK relaxation was suppressed by either L-NAME or ZnPP. However, it reappeared with combined L-NAME and ZnPP to subside again with K(+) increase or K(+) channel inhibition. In vivo, the ductus was patent in wild-type and NOS-deleted fetuses. Likewise, no genotype-related difference was noted in postnatal closure. CONCLUSIONS AND IMPLICATIONS: NO, formed mainly via eNOS, regulates ductal tone. NO and CO cooperatively mediate BK-induced relaxation in the absence of PGE(2). However, in the absence of PGE(2), NO and CO, BK induces a relaxant substance behaving as an endothelium-derived hyperpolarizing factor. Ductus patency is, therefore, sustained by a cohort of agents with PGE(2) and NO being preferentially coupled for reciprocal compensation.

Cyclooxygenase-1 and cyclooxygenase-2 in the mouse ductus arteriosus: individual activity and functional coupling with nitric oxide synthase.

1. Prenatal patency of the ductus arteriosus is maintained by prostaglandin (PG) E(2), conceivably in concert with nitric oxide (NO). Local PGE(2) formation is sustained by cyclooxygenase-1 (COX1) and cyclooxygenase-2 (COX2), a possible exception being the mouse in which COX1, or both COXs, are reportedly absent. Here, we have examined the occurrence of functional COX isoforms in the near-term mouse ductus and the possibility of COX deletion causing NO upregulation. 2. COX1 and COX2 were detected in smooth muscle cells by immunogold electronmicroscopy, both being located primarily in the perinuclear region. Cytosolic and microsomal PGE synthases (cPGES and mPGES) were also found, but they occurred diffusely across the cytosol. COX1 and, far more frequently, COX2 were colocalised with mPGES, while neither COX appeared to be colocalized with cPGES. 3. The isolated ductus from wild-type and COX1-/- mice contracted promptly to indomethacin (2.8 micro M). Conversely, the contraction of COX2-/- ductus to the same inhibitor started only after a delay and was slower. 4. N(G)-nitro-L-arginine methyl ester (L-NAME, 100 micro M) weakly contracted the isolated wild-type ductus. Its effect, however, increased three- to four-fold after deleting either COX, hence equalling that of indomethacin. 5. In vivo, the ductus was patent in all mice foetuses, whether wild-type or COX-deleted. Likewise, no genotype-related difference was noted in its postnatal closure. 6. We conclude that the mouse ductus has a complete system for PGE(2) synthesis comprising both COX1 and COX2. The two enzymes respond differently to indomethacin but, nevertheless, deletion of either one results in NO upregulation. PGE(2) and NO can function synergistically in keeping the ductus patent.

[Contribution to the knowledge on natural history of giant hepatic angioma]. / Contributo alla conoscenza della storia naturale dell'angioma epatico permagno.

Hepatic haemangiomas are mostly discovered by chance because of their limited dimensions. Their treatment is optional and very often an observing conservative strategy is adopted whilst a danger is foreseeing from different facts. Very different is the case of giant haemangiomas discovered because their bulk and discomfort coming from the compression exerted on near structures. In this cases a surgical treatment, segmentectomy or hemiepatectomy, are the current demanding choices. But if the volume of haemangioma is too bulky and occupies most hepatic parenchyma the necessary resection may be too extended and possibly dangerous. The two observations of the paper refer to two patients followed conservatively for over 20 years. In fact the volume of the haemangiomas in both patients was too large, the symptoms were only related to the weight of the mass and therefore a surgical solution was deferred to a possible worsening of the symptomatology. Such worsening didn't happen in the time for both the patients, demonstrating that the natural history of such lesion can also be very benign over many years.

An advantageous method to evaluate IgH rearrangement and its role in minimal residual disease detection.

A sensitive, safe and cheap method to detect minimal residual disease (MRD) is here presented. The PCR-GS technique includes: (a) a fluorescent PCR for the IgH region with CDR3/JH consensus primers; (b) the electrophoresis on an automatic sequencer (ABI PRISM 310); (c) the analysis of results by the GeneScan program. A total of 72 samples were analysed: 34/49 B-cell Non-Hodgkin's Lymphoma (NHL) (69%), six out of seven Multiple Myeloma (MM) (86%), 1/2 Hodgkin's Disease (HD) and 4/4 Acute Lymphoblastic Leukaemia (ALL) were found to be positive, showing a monoclonal IgH rearrangement. The major bias of the PCR-GS method are the 21% of false negatives, but 13/15 negative patients carried t(14;18); consequently, the association of the evaluation by PCR assays of the IgH and BCL2/JH rearrangement allowed to detect a molecular marker of B-neoplasia in more than 94% of tested samples.

Effects of Aroclor 1254 on intercellular communication in human keratinocytes.

It has been previously described that Aroclor 1254 can inhibit GJIC in rodent liver cells where it is known to be a tumor promoter, while the possibility that Aroclor 1254 exerts its inhibitory effects on GJIC in human keratinocytes and acts as a human skin tumor promoter, deserves further attention. In the present study the effects of Aroclor 1254 were examined on gap junction channel permeability, on connexin 43 (Cx 43) expression at mRNA and protein level and on ultrastructural modification to add further experimental evidence to its inhibitory effect on GJIC. The results were compared to those induced by 12-O-tetradecanoylphorbol-13 acetate (TPA), a tumor promoter known to be a potent inhibitor of GJIC in human skin cells and to those induced by benzo[a]pyrene (B[a]P) known for its genotoxic activity. Our data show increased Cx 43 protein expression in Aroclor 1254 and TPA-treated cultures compared to controls, decreased Cx 43 protein level in those exposed to B[a]P, while Cx 43 gene expression (Cx 43 mRNA) was unaffected by the treatments. In Aroclor and TPA-treated keratinocytes, the ultrastructural examination showed residues of junctional systems expressed by specular, short tracts of the faced plasma membranes. In contrast, the contacts between plasma membranes of adjacent B[a]P treated keratinocytes were more extended. A clear inhibition of gap junction channel permeability due to Aroclor 1254 and TPA was also manifest by Lucifer yellow dye test compared to B[a]P-treated cultures where dye spreading to the neighbouring cells and to the extracellular space occurred. The present data, in addition to confirming inhibition of GJIC mediated by Aroclor 1254 in human keratinocytes, which were found to be comparable to those induced by TPA, suggest that GJIC inhibition is associated with increased Cx 43 protein expression without significant modification of its gene expression.

Idiopathic arterial calcification of infancy: effectiveness of prostaglandin infusion for treatment of secondary hypertension refractory to conventional therapy: case report.

A premature baby had severe hypertension associated with idiopathic arterial calcification of infancy. Despite the fact that there was laboratory evidence of renin-mediated hypertension, the disease was refractory to specific renin antagonist and failed to respond to conventional medical treatment. Prostaglandin E1 (PGE1) infusion (dosage range 0.017-0.068 microgram/kg/min) promptly controlled hypertension on two occasions. The drug was given for a total of 65 days and then stopped after the appearance of severe thrombocytopenia; other side effects included sporadic hyperthermia and irritability. Blood pressure was then stabilized satisfactory by a multiple-antihypertensive regimen. In the light of these findings, we believe that PGE1 infusion is a possible therapeutic alternative for babies with idiopathic arterial calcification complicated by severe hypertension refractory to conventional treatment.

Cystic fibrosis in children: HRCT findings and distribution of disease.

To assess the type, severity, and regional lung distribution of cystic fibrosis (CF) lesions as shown using high-resolution CT (HRCT), comparing these findings with chest radiographs and pulmonary function tests (PFTs), we obtained HRCTs in 36 patients with CF (mean age 13), who were clinically stable. We assessed four lung regions (upper and lower, right and left) and assigned each a semiquantitative score for (a) bronchial abnormalities, (b) parenchymal abnormalities, and (c) overinflation, based on the severity and profusion of the corresponding lesions. A similar regional assessment of chest radiographs was also done using the Chrispin-Norman method. PFT results were correlated with the radiological data. On HRCT, bronchial lesions were present in 89% of the patients and in 78% of the regions; bronchiectasis was the predominant abnormality in our population, visible in 100% of the abnormal regions. Less frequent were bronchial wall thickening (48%) and mucous plugs (29%). Parenchymal abnormalities were recognizable in 58% of the patients and 31% of the regions; alveolar consolidation was more frequent (80%) than were destructive changes (36%). Overinflation was found in 81% of the patients and 85% of the regions. We found the severity and profusion of bronchial lesions and parenchymal destructive changes to be unevenly distributed among the different regions, the upper lungs being more heavily involved than the lower, particularly on the right. Alveolar consolidation and overinflation were more uniform in distribution. HRCT patient scores correlated significantly with radiographic scores (r = 0.861) and with PFTs, especially with forced expiratory volume for 1 s (FEV1; r = 0.658). HRCT can be useful in the clinical management of patients with CF, depicting the type and distribution of bronchial and parenchymal lesions, particularly when chest radiographic results are unclear. In the planning and postural drainage, special attention should be given to the apical and posterior parts of the lungs, especially on the right; these are the areas most frequently and most severely involved by the disease.

Combined use of ultrasonography and transhepatic percutaneous cholangiography in obstructive jaundice.

The authors have evaluated the results of ultrasonography (US) and transhepatic percutaneous cholangiography (PTC) in 85 patients. The comparative results of US and PTC in the diagnosis of the level (proximal or distal) and the nature (benign or malignant) of the obstruction and in the evaluation of the extension and the site of the lesion are illustrated. PTC is superior in the evaluation of the level and the nature of the obstruction while US gives more information about extension and site of the lesion. It is concluded that US and PTC should be considered as two complementary modalities.

Ultrasonographic aspects of inflammatory and neoplastic diseases of the gallbladder.

The authors present the incidence of the typical ultrasonographic signs of acute cholecystitis (46 cases), chronic cholecystitis (25 cases), cholecystosis (9 cases), empyema (28 cases) and carcinoma of the gallbladder (30 cases). Ultrasonography, together with the clinical picture, enables the identification of the lesion, its extension and evolution in most of the cases. Rarely do differential diagnostic problems exist. The ultrasonographic follow-up examination has been useful in acute inflammatory diseases to evaluate the efficiency of medical therapy and to detect complications which require immediate surgery. The authors emphasize the value of high-resolution real-time technique.

[Ultrasonographic evaluation of jaundiced patients: accuracy in 246 controlled cases (author's transl)]. / L'ecografia nella valutazione del paziente itterico: attendibilità su 246 pazienti controllati.

In 246 controlled jaundiced patients, the value of ultrasonography was confirmed. The differentiation of medical from surgical jaundice was 96% accurate. There was an increase in the overall accuracy due to technological developments and better scanning techniques. Nevertheless important diagnostic problems are still unresolved. Although the precise location of the obstructing lesion was determined in 86% of surgical case, the cause was established in only 69%. In medical jaundice diagnostic findings were observed only in congestive liver due to chronic heart failure and in some cases of cirrhosis.