N-acetylcysteine infusion improves hepatic perfusion in the early stages of systemic sclerosis.

The aim of our study is to evaluate portal and hepatic hemodynamic changes after N-acetylcysteine infusion in patients with systemic sclerosis. In an open-label study 40 patients with systemic sclerosis (SSc) were treated with 15 mg/kg/hour intravenous N-acetylcysteine for 5 consecutive hours in a single day. Hepatic flow volume, congestion index, portal flow volume, resistance index and pulse rate index were measured in each subject before and after infusion. In all patients mean hepatic flow volume (HFV) and mean portal flow volume (PFV) values after the five-hour infusion with NAC increased not significantly. In 22 selected patients with active capillaroscopic pattern, modified Rodnan Total Skin Score (mRTSS)<18 and mild-moderate score to vascular domain of disease severity scale (DSS), mean HFV increased significantly when compared with mean HFV of 18 SSc patients with late capillaroscopic pattern, mRTSS>18 and severe-end stage score to vascular domain of DSS. The results of our study demonstrate that NAC is able to increase HFV and total liver perfusion after a single infusion in SSc patients with low disease activity and severity scores.

Recurrent infections in patients with nickel allergic hypersensitivity.

Nickel (Ni) is the most common contact allergen among the general population in the industrialized world. Ni has been shown to exhibit immunomodulatory, if not immunotoxic, effects in several experiments conducted on humans and on rodents. This study tests the incidence of different infectious diseases in 100 patients with Ni hypersensitivity and compares it to data from 100 healthy volunteers. One hundred subjects with Ni hypersensitivity were enrolled. A group of 100 matched healthy volunteers with negative European standard patch test were enrolled as healthy controls. In patients with Ni hypersensitivity a higher incidence of recurrent herpes labialis (RHL), urinary tract infections (RUTI), genital candidiasis, and upper respiratory tract infections (RURTI) was detected. Fifteen patients with nickel allergic hypersensitivity (NAH) followed a Ni-poor diet. After a one-year diet a net reduction of incidence of RHL was found. Indeed, the number of episodes of RHL per year decreased from 6 +/- 2.75 to 2.4 +/- 1.2. Conversely, among the matched control group with NAH following a normal daily dietary nickel intake the RHL number did not show any statistically significant changes (6.1 +/- 1.7 vs 6 +/- 1.5 ). In conclusion, our study demonstrates a higher incidence of recurrent infections among patients with NAH. A low-Ni diet reduces the number of RHL episodes per year.

Involvement of p53 in phthalate effects on mouse and rat osteoblasts.

The role of two estrogen-mimicking compounds in regulating osteoblast activities were examined. Previously, our attention was focused on benzyl butyl phthalate (BBP) and di-n-butyl phthalate (DBP) since previous works showed that they enter the cytoplasm, bioaccumulate, modify actin cytoarchitecture and exert mitogenic effects involving microfilament disruption, and nuclear actin and lamin A regulation in Py1a rat osteoblasts. In this study we showed that BBP and DBP cause DNA base lesions both in MT3T3-E1 osteoblasts and in mouse primary calvarial osteoblasts (COBs). In addition, treatment with the above effectors caused an increase of p53 and phospho-p53 (ser-15 and ser-20) as well as an increase of apoptotic proteins with consequent decrease of cell viability. Moreover, treatment with phthalates did not modified p53 and phospho-p53 expression in Py1a rat osteoblasts. It is of relevance that in p53 knockdown mouse osteoblasts a proliferative effect of phthalates, similar to that observed in rat Py1a osteoblasts, was found. In conclusion, our data demonstrated that phthalates induce osteoblast apoptosis, which is, at least in part, mediated by p53 activation, suggesting that the proliferative effects could be due to p53 missing activation or p53 mutation.

Confocal evaluation of native and induced lectin binding contributes to discriminate between lingual gland glycocomponents in quail.

A confocal analysis was performed on the quail (Coturnix coturnix japonica) lingual salivary glands where the carbohydrate chains were studied by lectin histochemistry. For this purpose, appropriate FITC- and TRITC-conjugates were used for double binding also accomplished with sialidase digestion. The glycosidic components of the quail lingual salivary glands were found to be heterogeneously distributed on the different secretory structures as well as on the single secretory elements of each adenomere. The rostral portion of the anterior lingual gland was found to only secrete neutral glycocomponents, characterized by terminal beta-galactose, N-acetylgalactosamine and fucose residues in contrast to the caudal portion that was shown to be extremely heterogeneous and to produce sialylated glycoconjugates characterized by the terminal sequences sialic acid-beta-galactose-N-acetylgalactosamine, sialic acid-beta-galactose-N-acetylglucosamine, and sialic acid-alpha-N-acetylgalactosamine partly codistributed within secretory adenomeres. The posterior lingual gland was observed to be the major contributor to the secretion of salivary mucins containing sialoglycoconjugates with terminal sialic acid residues linked to beta-galactose-N-acetylgalactosamine or alpha-N-acetylgalactosamine often located in distinct secretory elements.

Confocal and electron microscopy to characterize sialoglycoconjugates in mouse sublingual gland acinar cells.

Double lectin labeling for confocal microscopy and lectin-protein A-gold binding for electron microscopy were applied to the mouse sublingual gland in order to study surface and cytoplasmic sialoglycoconjugates. For this purpose, serially cut sections were submitted to sialidase followed by incubation with lectins recognizing usually acceptor sugars for terminal sialic acids. At the electron microscope level, the residues subtended to sialic acid were individually identified on adjacent sections by an indirect technique of labeling, whereas with confocal microscopy the above sugars were simultaneously visualized on the same section by a double staining method using fluorescein isothiocyanate (FITC)- and tetramethylrhodamine isothiocyanate (TRITC)-conjugated lectins. Acinar cells were found to contain the terminal sequence sialic acid-beta-galactose in abundance while the sequence sialic acid-alpha-N-acetylgalactosamine appeared to be present in modest amounts. Both sialoglycoconjugates were homogeneously codistributed inside acinar cells. The combination with a saponification method also allowed the occurrence of C4 acetylated sialic acids linked to beta-galactose to be discovered, at the electron microscope level, on acinar cell secretory products.

Inter-alpha-trypsin inhibitor-related immunoreactivity in human tissues and body fluids.

The distribution of inter-alpha-trypsin inhibitor (ITI) and related inhibitors was investigated in normal human tissues and body fluids by using an enzyme-linked immunosorbent assay (ELISA) and a streptavidin-biotin-peroxidase immunohistochemical technique. ITI-related immunoreactivity was localized in different cell types of various organs, such as liver, kidney, testis, gross intestine, cutis and brain. Specific immunoreactivity was also detected in serum, urine and bronchial mucus. This widespread, but not ubiquitous pattern of localization suggests that, in addition to the well known plasmatic role, ITI and/or ITI-related inhibitors may play a number of different physiological roles in various human tissues.

Changes in vasoactive intestinal polypeptide (VIP) levels in the rabbit oviduct at different hormonal stages. An immunohistochemical study.

In this study we investigated immunohistochemically the distribution of VIP in ampullary and isthmic segments of the rabbit oviduct at different hormonal stages in order to correlate the presence of VIP with the morphological and functional differences between the two oviduct segments. Noticeable changes in the VIP-positive sites emerged between corresponding oviduct segments during the stages examined. A reduction in VIP presence was noted in oestrus and the lowest VIP values occurred one and three days after mating in the ampulla and the isthmus respectively. In the subsequent stages an increase of VIP was noted in both tracts which showed features comparable to that described in anoestrus. The levels and distribution of VIP is correlated with the functions of the oviduct segments concerned with egg transport and formation of a mucopolysaccharide envelope around blastocysts.

Characterization of glycoconjugates in an embryonic human epithelial line and changes consequent to adaptation to a hyperosmotic medium.

Cell surface and cytoplasmic glycoconjugates were characterized in embryonic human explant cells (a transformed heteroploid line) cultured in iso-osmotic medium (0.137 M NaCl) and in hyperosmotic medium (0.274 M NaCl) for 10 days in order to study the changes induced in these compounds by hyperosmoticity. Cytochemical and ultracytochemical staining selective for glycoconjugates was carried out. The following results were obtained: (1) glycoproteins, glycosaminoglycans and glycolipids are present on the cell surface and in the cytoplasm of the explant cells; (2) lectin histochemistry combined with glycosidase digestion demonstrated the presence of the disaccharides fucose-N-acetylglucosamine and sialic acid-beta-galactose as terminal sequences; (3) histophotometric evaluation of lectin labelling showed a noticeable decrease in histochemical reactivity of adapted cells; (4) plasma membrane cell coat decreased in adapted cells, which was emphasized by ultracytochemical reactions and a rearrangement of glycolipids in the cytoplasm.

Immunohistochemical localization of VIP and Met-enkephalin in the rabbit submandibular and sublingual glands.

The existence and distribution of vasoactive intestinal polypeptide (VIP), and Met-enkephalin pentapeptide were investigated by means of the peroxidase-antiperoxidase (PAP) technique in rabbit submandibular and sublingual glands. In the submandibular gland, VIP immunostaining was observed in some peripheral acinar cells, while in sublingual one VIP positive fibres surrounded semilunes. Ductal cells of both glands were also reactive. These findings suggested a role of VIP in regulating volume and composition of salivary secretion.

Glycoconjugates in the reproductive system of female rabbits in physiological estrogenic conditions.

Glycopeptide fractions were isolated from the uteri and oviducts of female rabbits in physiological estrogenic conditions. Both from the uterus and the oviduct considerably heterogeneous heteropolysaccharides were extracted, formed by hexoses, hexosamines, fucose, sialic acid, uronic acids and sulphates. During the estrus stage an increase is found in all glucide components, except for sialic acid, which, on the contrary, decreases. This decrease has been explained on the basis of histochemical data obtained in previous researches.