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Opuntia ficus indica cladodes possess a protective action against ethanol-induced ulcer in the rat. The major components of cladodes are carbohydrate polymers, mainly mucilages and pectin. To clarify the cytoprotective effects of cladodes on experimental ethanol-induced ulcer in rat, mucilages and pectin were extracted and were administered instead of cladodes. The above mentioned effects induced by cladodes may be attributed to mucilages, and not significantly to pectin.

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We evaluated the ability of two modified cyclodextrins, hydroxypropyl-beta-cyclodextrin (HP-beta-Cyd) and 2,6-di-O-methyl-beta-cyclodextrin (DM-beta-Cyd), to influence the percutaneous absorption through isolated human stratum corneum and epidermis (SCE) of celecoxib (CCB). Previous studies demonstrated that DM-beta-Cyd includes the drug, producing a significant increase of water solubility (0.5 mg/ml at 25 degrees C) and dissolution rate of CCB. In this work chemical-physical characterization studies were performed to evaluate the ability of HP-beta-Cyd to include CCB. We showed that only an external interaction could exist between CCB and HP-beta-Cyd that positively influences the water solubility of the drug (0.12 mg/ml at 25 degrees C for CCB-HP-beta-CyD system and 4.12 x 10(-3) mg/ml at 25 degrees C for free CCB). In vitro percutaneous experiments were performed using samples in solution and in suspension containing different Cyd concentrations. Both HP-beta-Cyd and DM-beta-Cyd enhanced drug flux through SCE by means of an increase of dissolution rate of the drug as well as a direct action on the stratum corneum (SC). Histological analysis of treated SCE showed a protective effect of the two Cyds towards an invasive action shown by CCB on SC.

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The protective effects of the juice of Opuntia ficus indica fruit (prickly pear) against carbon tetrachloride (CCl(4))-induced hepatotoxicity were examined in rats. The animals were treated orally with the juice (3 mL/rat) 2 h after administration of the hepatotoxic agent. Preventive effects were studied by giving the juice (3 mL/rat) for 9 consecutive days. On day 9 the rats received the hepatotoxic agent. Morphological and biochemical evaluations were carried out 24, 48 and 72 h after induction of the hepatic damage. Data show that O. ficus indica fruit juice administration exerts protective and curative effects against the CCl(4)-induced degenerative process in rat liver. Histology evaluation revealed a normal hepatic parenchyma at 48 h; the injury was fully restored after 72 h. Moreover, a significant reduction in CCl(4)-induced increase of GOT and GPT plasma levels is evident; these data are in agreement with the functional improvement of hepatocytes. O. ficus indica fruit juice contains many phenol compounds, ascorbic acid, betalains, betacyanins, and a flavonoid fraction, which consists mainly of rutin and isorhamnetin derivatives. Hepatoprotection may be related to the flavonoid fraction of the juice, but other compounds, such as vitamin C and betalains could, synergistically, counteract many degenerative processes by means of their antioxidant activity.

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In the present work we report a Fourier Transform Infrared (FT-IR) analysis performed on rat encephalon samples in the CH-OH vibrational stretching region (2400-3800) cm(-1), in order to reveal the presence of a very diffuse commercial benzodiazepine: VALIUM. The comparison between the spectral features of normal brain and the ones of samples with administrated substance has unambiguously showed that the CH stretching region seems not to suffer from any change for the pharmacological treatment, instead the OH band is strongly modified probably due to the presence of a new spectral contribution characteristic of diazepam molecule.

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In Sicily folk medicine, Opuntia ficus indica (L.) Mill. cladodes are used for the treatment of gastric ulcer. We studied the effect of administration of lyophilized cladodes on experimental ethanol-induced ulcer in rat. In this paper, we report the ultrastructural observations of gastric mucosa. The ultrastructural changes were observed by trasmission electronic microscopy (TEM) confirming the protective effect exercised by administration of lyophilized cladodes. Pre-treatment test in rats revealed a protective action against ethanol-induced ulcer. Probably, the mucilage of Opuntia ficus indica is involved.

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The effect of cannabinoid drugs (i.p.) on cold/restraint stress-induced gastric ulcers was studied in rats. The cannabinoid receptor agonist (WIN 55,212-2, 0.1-1 mg/kg), but not the less active isomer WIN 55,212-3 (1 mg/kg), reduced gastric ulceration. The protective effect of WIN 55,212-2 (1 mg/kg) was counteracted by the cannabinoid CB1 receptor antagonist SR141716A, but not by the cannabinoid CB2 receptor antagonist SR144528. These results indicate that the antiulcer effect of the cannabinoid receptor agonist WIN 55,212-2 is mediated by cannabinoid CB1 receptors.

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The effects of chronic intragastric administration of the aerial parts decoction of Teucrium divaricatum Heldr. ssp. divaricatum (Labiateae) on experimental acetylsalicylic acid (ASA)-induced ulcer were studied in rats. The ulcer index and histological mucosa regeneration were evaluated. The ulcer index significantly decreased (U.I. 1.7+/-1.5; P<0.05) after treatment with a lyophilized decoction of T. divaricatum (500 mg/kg os), once daily for 7 days, compared to the control (U.I. 11.4+/-2.3). The ultrastructure modifications of gastric mucosa were observed by transmission electronic microscopy (TEM) confirming the antisecretory effect exercised by administration of the T. divaricatum decoction. Treatment with T. divaricatum seems to block up parietal cell acid secretion and to stimulate in the chief cells the formation of zymogen granules.

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Our previous ultrastructural and immunohistochemical studies, in vivo and in vitro, have shown important modifications of the basement membrane of psoriatic skin, which could play a key role in the alterations of keratinocyte adhesion, migration, proliferation and differentiation. In order to complete the morphological examination of all the structures in the dermoepidermal junction of psoriatic skin, we carried out a scanning electron microscopic study using biopsies taken from eight psoriatic patients. The biopsies were fixed in a mixture of 0.2% paraformaldehyde and 0.25% glutaraldehyde in 0.1 M cacodylate buffer at pH 7.4. The specimens were then frozen in liquid nitrogen and fractured following the natural cleavage planes and observed under a Jeol JSM-6301F field emission scanning electron microscope operating at 1.8-2.0 kV. The basal keratinocytes observed showed pore-like depressions on the lateral plasmalemma and villous-like projections in very dilated intercellular spaces. Moreover the basal cell plasma membrane was seen to rest on the papillary dermis without interposition of the lamina densa. The detachment of some keratinocytes enabled the examination of the lamina densa, which appeared slightly granular with numerous focal interruptions through which it was possible to observe the underlying collagen fibres. These findings, together with previously reported findings, support the hypothesis that in psoriasis molecular and structural alterations of the dermoepidermal junction are present, that could fundamentally alter the regulation of the cytomorphological processes and the normal functions of the basement membrane.

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Psoriasis is a typical hyperproliferative epidermal disease whose aetiopathogenesis is still to be defined. One of the most likely hypotheses is that it has a neurogenic origin correlated with an altered release of some neuropeptides by sensitive cutaneous nerves via antidromic pathways. As there are conflicting reports about the existence of cutaneous nerve alterations in psoriasis, we carried out an immunolocalization study using the protein gene product 9.5 as a marker for neuronal structures observed by confocal laser scanning microscopy in order to determine the pattern of sensory nerves in psoriatic skin. The investigation was carried out on cutaneous biopsies taken from involved (mature and long-established lesions) and uninvolved skin of ten patients with extensive chronic plaque psoriasis. In uninvolved psoriatic skin a significant decrease in epidermal nerve fibres was found, a further decrease was observed in mature lesions and almost a complete lack of epidermal nerve fibres in long-established psoriatic lesions. The reduction in epidermal nerve fibres and the consequent loss of relationship between these nerve structures and the skin immunocompetent cells (antigen-presenting cells, Langerhans cells, keratinocytes) might be a factor of fundamental importance in the self-maintenance of the disease.

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In previous researches the Authors hypothesized that the loss of cytoskeletal proteins such as desmin and vinculin lead to degenerative ultrastructural changes which occur in muscular disuse atrophy. In order to support this hypothesis they carried out a morphometric, structural, ultrastructural and immunofluorescence study on the soleus muscle of albino rats after resection of the ischiatic nerve. It was demonstrated that a chronological sequence of the damage took place in particular three levels of damage. The last level of damage proved to be irreversible; the first level assured complete recovery in the case of rapid reinnervation, whereas the possible reversibility of the second level remained open to question. The disappearance of vinculin and desmin was observed in a period between 72 hours and 7 days, i.e. before the appearance of ultrastructural damage. On this ground the Authors explained the correlation between the loss of the proteins and degenerative changes. In conclusion the Authors correlated the gene expression of cytoskeletal and contractile proteins with the neuropeptides released by motor axon.

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In reference to a possible neuropathy in the pathogenesis of infantile hypertrophic pyloric stenosis (IHPS), previous studies have described alterations in peptidergic transmission while others have recently attributed an important role to nitrinergic activity. Little attention has been given to the organization of the extracellular matrix (ECM) and the constituent cytoskeleton and subsarcolemma of the pyloric smooth-muscle cell. To study a possible relationship between neuronal and muscular elements in IHPS, 9 biopsies from patients with IHPS and 5 biopsies of normal pylorus were examined using immunohistochemical techniques with regard to the distribution of nerve cells and fibers (bNOS and PGP 9.5) and the ECM (laminin) and cytoskeleton (talin, vinculin, dystrophin, alpha-smooth iso-actin, desmin) components of the pyloric muscle. Our results showed anti-protein gene product 9.5 and b-nitric oxide synthase immunoreaction respectively reduced or absent in nerve fibers with a positive reaction inside the ganglion cells. An uneven distribution of the ECM component laminin was evident, together with a negative immunoreaction to talin and dystrophin. The imunolocalization of vinculin, alpha-smooth iso-actin, and desmin was similar to the controls. Our findings suggest that there is a close relationship between the nerve and muscle elements in the pathophysiology of IHPS and that non-alteration of some elements of cytoskeleton organization can play an important role in regaining pyloric function after pyloromyotomy.

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Recent studies support the presence of adherens junctions at the dermal-epidermal interface in addition to hemidesmosomes. In this area the integrin/actin-containing cytoskeleton connection occurs by means of a complex of proteins called actin-associated proteins (talin, vinculin, alpha-actinin). As previous studies have demonstrated the presence in psoriatic lesions of marked alterations in both the basement membrane molecular composition and the polarized expression of integrins, we decided to determine whether alterations in the behaviour of the actin-associated proteins could be demonstrated. We thus undertook an immunolocalization study with monoclonal antibodies directed against talin, vinculin, and alpha-actinin in cutaneous biopsies taken from involved and uninvolved skin of 12 patients with extensive chronic plaque psoriasis. The findings showed an almost total lack of reaction against talin and vinculin in the basal layer and an increased positivity against the proteins in the suprabasal layers. Similar, though less marked, alterations were present in uninvolved psoriatic skin. These results, in agreement with those of previous studies, confirm serious alterations in the matrix protein/cytoskeleton connection system, and support the hypothesis that this condition may play a key role in the pathogenesis of the disease.

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Previous studies have demonstrated the presence in psoriatic lesions of ultrastructural and molecular alterations of the basement membrane and an altered polarized distribution of the integrins; this latter alteration has also been observed in uninvolved skin. The aim of the present study was to determine, by means of immunolocalization with monoclonal antibodies directed against laminin 1 and type IV collagen and using confocal scanning laser microscopy, whether there are also alterations of the main components of the basement membrane in uninvolved skin. The findings showed a discontinuous and fragmented staining of laminin 1 and a normal distribution of type IV collagen. Taking into account both these results and the results of studies on epithelial cell lines, the authors hypothesize the existence of a functional deficit in psoriatic keratinocytes affecting the synthesis of the alpha 1 subunit of laminin. This deficit would explain: (1) the incapacity to produce mature trimeric laminin; (2) the altered assembly into a distinct basal lamina; (3) the loss of keratinocyte adhesion to the basement membrane; (4) alterations in the polarized distribution of the integrins; and (5) the consequent total or partial block of the cell signals regulating the processes of cytomorphosis. Already present in uninvolved skin, and enhanced by various irritative stimuli, this situation could be decisive for the appearance of psoriatic lesions.

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BACKGROUND: The costameres in skeletal muscle fibers were first described by Pardo et al. (1983a) and have been defined as transverse circumferential elements of the cytoskeleton associated to the sarcolemma. Specific immunostaining for vinculin shows that the costameres overlie I bands. However, an exact correlation between the costameres and the Z line is uncertain, although approximately 10 proteins so far have been localized in the costameres. To define the exact localization of costameres in human skeletal muscle fibers, we carried out an immunofluorescence study using confocal scanning laser microscopy on the fascia lata muscle of adult males. METHODS: Samples were fixed in 3% paraformaldehyde; frozen sections were treated with antivinculin, antitalin, antidesmin, and anti-alpha-actinin, then immunostained with TRITC. For double localization, the TRITC-streptavidin, as a marker for vinculin and FITC-streptavidin a marker for desmin, were used. RESULTS: The distance between two subsequent transverse lines of actininf indicated that muscle fibers were well stretched. Processing, with different software functions of the images obtained using CLSM, shows that vinculin and talin are only present in the sarcolemmal lattice. Immunostaining for vinculin and double immunostaining for vinculin and desmin demonstrate that costameres superimpose underlying I bands without interruption at the Z line. Immunostaining for talin showed that the protein is located in correspondence with the I band and M line. CONCLUSIONS: We believe that costameres are "proteic machinery." The findings of the present study suggest that it is possible to determine the width and the period of each proteic component. In addition, we indicate that costameres are present in correspondence with M line.

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Numerous studies have been performed on the effects of omeprazole, a powerful inhibitor of gastric acid secretion, on the various morphotypes of oxyntic mucosa, whilst scant attention has been paid to modifications induced by this drug on surface epithelial mucosa. The authors carried out a SEM study on bioptic fragments removed at gastric level from 15 patients receiving omeprazole treatment for duodenal ulcer and/or reflux esophagitis, but apparently free from lesions to the mucosa of the body of the stomach. Biopsies were performed before the start, after two months and after seven-ten months of treatment. The results of basal biopsies showed an hypersecretive trend in surface epithelial cells, with frequent dissolution of the apical plasmalemma and emptying of cell bodies. After two months of treatment the hypersecretive phenomena regressed, whereas the mucosa appeared hypertrophic and presented typical cell polymorphism in some areas. After seventeen months of treatment the mucosa showed normal characteristics, except in one case in which there was a trend towards atrophy. In conclusion, the authors attribute the hypertrophic-dysplastic modifications observed after medium-term treatment to hypergastrinemia, secondary to treatment, and suggest careful morphological control follow-up during the course of treatment so as to obtain an early diagnosis of a possible deviation towards intestinal metaplasia.

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We report the second infant of nonconsanguineous parents with epidermolysis bullosa junctionalis associated with urinary bladder exstrophy, epispadias, anteriorized anus, and bilateral inguinal hernias. The family history also included the death of a maternal cousin due to epidermolysis bullosa. Our diagnosis was based on electron microscopy and immunofluorescence evidence. This patient is reported because of the rarity of this constellation of findings.

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We have demonstrated both in vivo and in vitro that Cyclosporin (CsA) treatment during psoriasis induced a regression of typical keratinocyte alterations and normalization of the basement membrane (BM). It is also known that the structure of BM implies cohesion between the networks formed by laminin and type IV collagen and that these components positively influence the cytomorphosis processes of keratinocytes. According to these results, we have evaluated, by immunohistochemical study, the behaviour of laminin and type IV collagen on psoriatic skin prior to the therapy and at the end of pharmacological treatment with CsA. This study was carried out on biopsies of involved skin taken from 12 patients with severe psoriasis and with PASI between 50 and 70. Our results can be summed up as follows: Untreated psoriasis: absence of laminin within BM; modest staining in basal keratinocytes; intense staining in suprabasal keratinocytes; discontinuous staining of Type IV collagen in the BM. After treatment: evident and continuous staining of laminin and Type IV collagen within the BM. The obtained results confirm the positive effect of immunomodulation determined by CsA in the regulation of the functional activity of cells implicated in BM component production. In conclusion, the authors discuss the pathogenesis of the disease.

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