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Biomedical subjects

A Tursi

Publications and source records attributed to A Tursi.

At least 109 records · Page 6Linked to original sources
PubMed1997

Expression of prostaglandin endoperoxide H synthase 1 and 2 in human placenta at term.

Prostaglandins play an important role in reproduction, particularly in pregnancy and parturition. We investigated the expression of prostaglandin endoperoxide H synthase (PGHS) 1 and 2, key enzymes in prostaglandin biosynthesis, in the human placenta at term. Northern blot analysis of placenta total and poly(A)+ RNA failed to detect significant levels of PGHS-1 mRNA, using a human PGHS-1 specific DNA probe. In contrast, definite PGHS-2 mRNA bands, with a calculated size of about 4.5 kb, were observed in Northern blots of placenta poly(A)+ RNA, using a PGHS-2 specific DNA probe. Moreover, PGHS-1 and PGHS-2 expression was assessed at the translational level by Western blot analysis. Thus, using three highly specific antibodies, we found a selective expression of PGHS-2 immunoreactive protein. These results indicate that PGHS-2 is the PGHS isoform prevalently expressed in the human placenta at term and support the hypothesis that PGHS-2 plays a prominent role in the maintenance of pregnancy, in line with the proposed anti-apoptotic and growth promoting properties of this enzyme.

Blotting, Northern↗
PubMed1997

Short-term low-dose triple therapy with azithromycin, metronidazole and lansoprazole appears highly effective for the eradication of Helicobacter pylori.

BACKGROUND: Although the OCN (omeprazole, clarithromycin and nitroimidazoles) short-term low-dose regimens are regarded as 'the standard' in the treatment of Helicobacter pylori infection, azithromycin is a new-generation, acid-stable macrolide which may prove particularly useful for a new short-term low-dose triple therapy regimen. OBJECTIVE: To further improve OCN eradication treatments by reducing both the number of pills and the total cost. METHODS: A new short-term low-dose triple therapy (LAM) using lansoprazole 30 mg once a day for 1 week, azithromycin 500 mg once a day for 3 days, and metronidazole 250 mg twice a day for the same 3 days, was administrated to 60 patients presenting with H. pylori-positive gastritis with or without peptic ulcer, and compared with the classic 'Bazzoli regimen' (OCT: omeprazole, clarithromycin, tinidazole) in 60 matched patients. H. pylori infection before and after therapy was evaluated by a rapid urease test, conventional histology and toluidine-stained semi-thin sections. Three biopsies from the corpus and three from the antrum were taken during endoscopical examination before and 7-8 weeks after discontinuation of the treatment. Patient compliance, drug tolerance and drug costs were also taken into consideration. RESULTS: H. pylori infection was eradicated 7-8 weeks after treatment in 56 of the 60 patients in the LAM group (93.3%), and in 52 of the 57 patients in the OCT group who completed the treatment (91.2%), with no statistical difference. When gastric or duodenal ulceration was present, ulcer healing was observed in all cases. CONCLUSION: The new proposed short-term low-dose triple therapy (LAM) appears to be as effective as the OCT for the eradication of H. pylori infection. The new treatment, however, seems to have advantages in terms of drug tolerance, patient compliance and therapy cost.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1997

IgE responses to Dermatophagoides pteronyssinus native major allergens Der p 1 and Der p 2 during long-term specific immunotherapy.

We investigated by ELISA the IgE response to whole extract of the house-dust mite Dermatophagoides pteronyssinus (Dp) and to the native major allergens, Der p 1 and Der p 2, in sera from 18 adult patients (group A) with Dp-allergic asthma before (t0) and 1, 2, 3, and 4 (t1-t4) years after subcutaneous specific immunotherapy (SIT). A qualitative reduction (P = 0.05) of the IgE responses to Dp and Der p 2 was observed from t1 to t4, but a highly statistical significant decrease appeared at t3 (P < 0.01). With regard to Der p 1 IgE values, the immunotherapy induced a significant decrease (P < 0.01) at t3, but not before. In group A, the IgE responses to Der p 1 and Der p 2 were not correlated at t0 (rs = 0.31; P = 0.21) but were correlated at t3 (rs = 0.78; P = 0.001). We also examined sera from 14 adult patients (group B, same SIT schedule as group A) who were without respiratory symptoms at the end of the third year (t3) of Dp SIT. At this time (t3), there were no significant differences in Der p 1 and Der p 2 IgE levels between group A and group B.

Adult↗
PubMed1997

The growth of primary low-grade B-cell gastric lymphoma is sustained by Helicobacter pylori.

BACKGROUND: The growth of primary low-grade B-cell gastric mucosa-associated lymphoid tissue (MALT) lymphoma is an antigen-dependent process CASE: We were able to document the influence of Helicobacter pylori on the natural history of primary low-grade B-cell gastric MALT lymphoma in a case investigated by means of polymerase chain reaction for IgH rearrangement. In this case the presence or absence of the bacterium appeared to affect both clinical manifestations and histologic features of the neoplasia, with an acceleration or a slowing down of the neoplastic expansion, respectively. CONCLUSIONS: We identified H. pylori as an antigenic stimulus that supports the growth of MALT-type lymphoma. This finding enables us to make some considerations about the management of the disease.

Aged↗
PubMed1997

Eosinophils in allergic diseases: immunopharmacological regulation.

Eosinophils (EOS) are cells that have excited great interest among researchers because of their involvement in many phenomena, and particularly those of defence against parasitic infestations and of modulation of allergic inflammatory reactions. The ontogenesis, morphology and functions of EOS are described, and especially the receptors and chemical mediators they synthesize. Particular attention is paid to the EOS role as a central element in allergic inflammation processes, able to maintain the inflammatory state by producing specific cytokines and to cause tissue damage by producing free radicals. The cell's role in the defence against parasitic infestations is also considered. Finally, emphasis is placed on EOS capacity for immunopharmacological regulation by means both of active secretion of regulating substances and of modulation of other substances, able to inhibit certain phases of allergic inflammation.

Adjuvants, Immunologic↗
PubMed1997

[Intestinal permeability].

Intestinal mucosa has an absorptive function and acts also as a selective barrier against potential antigenic, toxic and carcinogenic substances. Intestinal permeability can be defined as the capacity of mucosal surface to be penetrate by specific substances through unmediated diffusion. There are two theories about molecular permeation routes: the first one hypothesizes a transcellular (through small pores), a paracellular (through big channels) and a lipophilic pathways; the second one gives a key role only to paracellular tight-junctions. In many diseases we can find changes in intestinal permeability evaluable by simple and non invasive tests, administering "per os" probe molecules. These substances cross the epithelium in different way and amount according to their physicochemical features and mucosal integrity; then they reach circulation and are eliminated in urines where they can be detected. The most frequently molecules used are mono/disaccharides, 51Cr-labelled ethylenediaminetetraacetate (51Cr-EDTA) and polyethylene glycol (PEG). This simple method has become more and more used for diagnostic and speculative aims. These intestinal permeability tests have a low specificity so they cannot be used for a definitive diagnosis of intestinal disease; nevertheless, the high sensitivity for intestinal mucosal damage could make them a necessary method to evaluate mucosal integrity after therapy, to select patients with a specific symptoms and to support, particularly in pediatric populations, more specific and invasive diagnostic tests.

Humans↗
PubMed1997

[The modes of transmission of Helicobacter pylori infection].

Helicobacter pylori plays an essential role in the development of several both acid-related and neoplastic gastroduodenal pathologies. There are still uncertainties about the transmission routes and the sources of H. pylori infection. Man is the only well established "reservoir" of H. pylori, while the role of other mammalians (cat, pig, primates), as sources of infection, is still controversy. Literature data suggest four different modalities of transmission of the infection: faeco-oral, oro-oral, gastro-oral, gastro-gastric. By faeco-oral route, the bacterium, excreted with faeces, might colonize water sources, becoming so available to be transmitted to man and other mammalians. By oro-oral route, H. pylori, which colonizes dental plaque and saliva, may be transmitted by saliva to other individuals. The gastro-oral route is the typical modality of transmission in the childhood, when H. pylori uses the mucous achlorhydric vomitus of the children to infect a new host. Finally, by gastro-gastric route the bacterium might be transmitted by endoscopic procedures. In conclusion, we believe the different modalities of transmission may be contemporaneously involved, since none per se is able to explain the widespread occurrence of H. pylori infection.

Disease Susceptibility↗
PubMed1997

Long-term follow-up of disappearance of gastric mucosa-associated lymphoid tissue after anti-Helicobacter pylori therapy.

OBJECTIVES: Mucosa-associated lymphoid tissue (MALT) can develop in gastric mucosa after Helicobacter pylori infection, but not all H. pylori-positive patients develop acquired MALT, probably because of different levels of individual susceptibility against H. pylori-antigens. Our aim was to conduct long-term follow-up in MALT-positive and MALT-negative patients after H. pylori had been eradicated to determine what happens after H. pylori reinfection. METHODS: We studied 30 H. pylori-positive patients, 15 MALT-positive patients (group A), and 15 MALT-negative patients (group B). After the eradication of H. pylori and disappearance of acquired MALT in group A, follow-up was conducted by repeated endoscopic biopsies every 4-6 months for a mean period of 30.6 months (31.6 months for group A, 29.4 for group B). RESULTS: During follow-up, three group A patients were reinfected by H. pylori, and MALT recurred. Moreover, in each patient, it was the same grade of acquired MALT that had previously been diagnosed (grade 2 in two patients and grade 3 in one). A second course of anti-H. pylori treatment resulted both in eradication of H. pylori and the disappearance of MALT. Conversely, none of the group B patients with H. pylori reinfection developed MALT. However, in those patients, too, a second course of treatment eradicated the H. pylori. CONCLUSIONS: Our study shows that acquired MALT appears after reinfection with H. pylori only in patients who previously had that condition. Moreover, the grade of acquired MALT that reappears is the same as previously diagnosed. These findings demonstrate that not only H. pylori infection but also individual susceptibility may be important in determining both the presence of acquired MALT and its grade. However, strict follow-up is not advisable in MALT-positive patients, because no patient developed MALT-lymphoma during follow-up.

Adult↗
PubMed1997

Regression of a primary gastric MALT lymphoma with extensive antrum lesions by Helicobacter pylori eradication.

Some studies have suggested that low-grade MALT lymphoma may regress after eradication of Helicobacter pylori infection. This case report describes a Helicobacter pylori-positive patient with very extensive ulcerated polypoid lesions involving gastric antrum and prepyloric region, diagnosed by histology, pathological analysis and staging procedures as low-grade MALT lymphoma of EI1 stage. The patient received eradication therapy with a one-week course of omeprazole plus amoxicillin plus clarithromycin and was seen at follow-up after 3, 6 and 15 months. At follow-up, Helicobacter pylori eradication appeared to be in resolution of the macroscopic and histological features of the lymphoma, as confirmed by endoscopic, histological and molecular findings. Until now, only a few cases with a large gastric MALT lymphoma has successful treatment of Helicobacter pylori resulted in regression. Although additional follow-up is needed, it would appear that Helicobacter pylori infection cure may be effective also for large low-grade stage EI1 MALT lymphoma.

Aged↗