Transjugular intrahepatic portosystemic shunt in non-cirrhotic portal hypertension related to cystic fibrosis in a lung transplant patient.

Liver involvement is not uncommon in patients with cystic fibrosis (CF). Even if serious complications as non-cirrhotic portal hypertension, cirrhosis and liver failure rarely occur, they are associated with impaired survival and reduced quality of life. Herein, we have reported the first case of a patient with CF and non-cirrhotic portal hypertension who underwent transjugular intrahepatic portosystemic shunt placement for recurrent variceal bleeding after bilateral lung transplantation, and we have reviewed the available literature pertaining to this field.

Human prolidase and prolidase deficiency: an overview on the characterization of the enzyme involved in proline recycling and on the effects of its mutations.

Here we summarized what is known at the present about function, structure and effect of mutations in the human prolidase. Among the peptidases, prolidase is the only metalloenzyme that cleaves the iminodipeptides containing a proline or hydroxyproline residue at the C-terminal end. It is relevant in the latest stage of protein catabolism, particularly of those molecules rich in imino acids such as collagens, thus being involved in matrix remodelling. Beside its intracellular functions, prolidase has an antitoxic effect against some organophosphorus molecules, can be used in dietary industry as bitterness reducing agent and recently has been used as target enzyme for specific melanoma prodrug activation. Recombinant human prolidase was produced in prokaryotic and eukaryotic hosts with biochemical properties similar to the endogenous enzyme and represents a valid tool both to better understand the structure and biological function of the enzyme and to develop an enzyme replacement therapy for the prolidase deficiency (PD). Prolidase deficiency is a rare recessive disorder caused by mutations in the prolidase gene and characterized by severe skin lesions. Single amino acid substitutions, exon splicing, deletions and a duplication were described as causative for the disease and are mainly located at highly conserved amino acids in the sequence of prolidase from different species. The pathophysiology of PD is still poorly understood; we offer here a review of the molecular mechanisms so far hypothesized.

Alterations of energy metabolism and glutathione levels of HL-60 cells induced by methacrylates present in composite resins.

OBJECTIVES: Methacrylic compounds such as 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and bisphenol A glycerolate (1 glycerol/phenol) dimethacrylate (Bis-GMA) are largely present in auto- or photopolymerizable composite resins. Since the polymerization reaction is never complete, these molecules are released into the oral cavity tissues and biological fluids where they could cause local adverse effects. The aim of this work was to verify the hypothesis that the biological effects of HEMA, TEGDMA and Bis-GMA - at a non-cytotoxic concentration - depend on the interaction with mitochondria and exert consequent alterations of energy metabolism, GSH levels and the related pathways in human promyelocytic cell line (HL-60). METHODS: The biological effects of methacrylic monomers were determined by analyzing the following parameters: GSH concentration, glucose-6-phosphate dehydrogenase (G6PDH) and glutathione reductase (GR) activity, oxygen and glucose consumption and lactate production along with cell differentiation and proliferation. RESULTS: All monomers induced both cellular differentiation and decrease in oxygen consumption. Cells treated with TEGDMA and Bis-GMA showed a significant enhancement of glucose consumption and lactate production. TEGDMA and HEMA induced GSH depletion stimulating G6PDH and GR activity. CONCLUSIONS: All the monomers under study affect the metabolism of HL-60 cells and show differentiating activity. Since alterations in cellular metabolism occurred at compound concentrations well below cytotoxic levels, the changes in energy metabolism and glutathione redox balance could be considered as potential mechanisms for inducing clinical and sub-clinical adverse effects and thus providing useful parameters when testing biocompatibility of dental materials.

Human salivary peptides derived from histatins.

Human saliva from a healthy donor was subjected to fractionation by gel chromatography and six pools were collected and analysed by MALDI-TOF-MS and HPLC-ESI-MS. Three peptides, corresponding to 888.3, 687.3, and 524.1 amu and SNYLYDN, YLYDN, and LYDN sequences (determined by automated Edman sequencing), were isolated from pool 4. YLYDN was not previously described in human saliva. The peptides show the common C-terminal sequence of histatin 3 and histatin 1. To exclude the possibility that the three peptides were an artifact of the purification procedure, nine samples of human saliva were collected from healthy donors, immediately acidified with 0.2% TFA, and analysed by RP-HPLC-ESI-MS. The three peptides were detected in all the analyzed samples. SNYLYDN was always found at a concentration higher than that of YLYDN and LYDN. A correlation analysis performed on quantitative data indicated that the three peptides derive only from histatin 3. Other already known histatins also were searched for in the chromatogram. Histatins 1, 2, 3, 5, 6, 7, 8, and 10 were observed, although not in all samples analyzed, whereas other minor histatins were not detected.

Surfactant apoprotein A modulates interleukin-8 and monocyte chemotactic peptide-1 production.

Previous studies have shown that surfactant apoprotein A (SP-A) and natural or synthetic surfactant can modulate the release of pro-inflammatory cytokines from alveolar mononuclear phagocytes. The aim of this study was to assess whether SP-A or Surfactant (Surf) from patients with pulmonary alveolar proteinosis (PAP) can affect the release of two chemokines (interleukin (IL)-8 and monocyte chemtactic peptide (MCP)-1) from human monocytes and rat lung type-II cells. In addition IL-8 and MCP-1 levels were assessed in the brochoalveolar lavage fluid (BALF) of seven patients with PAP and compared with those in a group of control subjects (n=5). SP-A, tested over a wide range of concentrations, significantly increased IL-8 and MCP-1 release from monocytes. SP-A retained its activity after collagenase digestion, but was not active after heat treatment. The release of IL-8 by monocytes was also stimulated by Surf. Finally, median BALF IL-8 and MCP-1 levels in PAP patients were significantly higher than in controls (9.50 and 9.51 pg x mL(-1) in controls versus 151.95 and 563.70 pg x mL(-1) in PAP, respectively) and significantly correlated with SP-A concentrations in BALF. Overall the results of this study support the view that the high content of alveolar surfactant apoprotein A may contribute to the upregulation of chemokine release in pulmonary alveolar proteinosis, thus contributing to airway inflammation.

"Hot" carcinoma of the thyroid. Case reports and comments on the literature.

It seems somewhat difficult to exactly define the real number of case reports concerning the association of hyperfunctioning thyroid node and carcinoma; the overall incidence of this condition seems, however, to be very rare. Different inclusion criteria are probably a fairly relevant cause of variability in the number of cases reported during the years. A basic classification scheme, as the one here reported, may be of help in characterizing the different possible conditions: 1. the coexistence of carcinoma and focally hyperfunctioning tissue in the same gland but at different locations (not uncommon); 2. the presence of such a large tumour mass that it can compete with normal tissue for tracer uptake, despite being hormonogenetically uneffective in itself; 3. the carcinoma located in the hyperfunctioning adenoma; 4. the real hyperfunctioning carcinoma, where coincidence between hyperfunctioning tissue and malignancy is complete (very rare). Two cases are reported here, respectively belonging to the third and fourth of these categories (the most challenging from a diagnostic point of view). The matter is intrinsically poor from a statistical standpoint: it is therefore difficult to draw definitive conclusions on the subject in operative terms. It is however felt that the systematic evaluation of oncological risk in thyroid nodes, occasionally recommended in the literature, may be cumbersome and not necessarily cost-effective.

Inhibition of human neutrophil elastase by erythromycin and flurythromycin, two macrolide antibiotics.

Fourteen-member-ring macrolides are antibiotics with a variety of anti-inflammatory activities, and have repeatedly been reported to reduce mucus hypersecretion in conditions such as cystic fibrosis and bronchiectasis. Their structure is characterized by a macrocyclic lactone ring. Because human neutrophil elastase (HNE) plays a crucial role in the vicious circle leading to mucus hypersecretion, and lactones are known to be elastase inhibitors, we hypothesized that macrolides might directly inhibit elastase. To investigate this hypothesis we designed a series of spectrophotometric experiments using a chromogenic substrate with two macrolides, erythromycin (Er) and flurythromycin (FE). We determined the 1st order rate constant (k(obs)) by inhibition and competitive substrate assays, the latter allowing us to calculate the substrate binding constant or inhibition constant and the acylation rate constant (k(a)). A proflavine displacement assay was used to determine the deacylation rate constant (k(d)). Both Er and FE are good HNE inhibitors, showing a high k(a) and a low k(d). Because the number of turnovers per inactivation of Er was congruent with 20-fold higher than that of FE, we supposed that the lower reactivation of HNE-FE was due to the formation of a more stable inactivated enzyme. This hypothesis was confirmed by the hydrazine reactivation of the acyl enzyme. For Er we identified a k(d) only, whereas for FE, in addition to the k(d), an alkylation constant (k(2)) was calculated, correlated to a fully inactivated enzyme. From our kinetics data, we therefore conclude that Er acts as an alternate substrate HNE inhibitor, whereas FE acts as an inactivator.

[False mass in the left atrium... or better: true mass in false atrium]. / Falsa massa in auricola sinistra ... o meglio: vera massa in falsa auricola.

We report the case of a 59-year-old man who underwent transesophageal echocardiography following a cryptogenic minor stroke. An image of a solid mass of the left atrial appendage, highly suggestive of a thrombus, was observed. The patient was treated for 10 weeks with oral anticoagulants. Because of the absence of changes in the echocardiographic appearance of the mass at follow-up, the patient was submitted to surgery. At surgical exploration no endocavitary thrombus was found, but the left atrial appendage appeared hypoplastic and dysmorphic. A biopsy was taken and the left atrial appendage was plicated. To our knowledge, this is the first report of a case of dysmorphism of the left atrial appendage mimicking a left atrial thrombus in a patient with cryptogenic minor stroke.

Leigh disease: clinical, neuroradiologic, and biochemical study of three new cases with cytochrome c oxidase deficiency.

Three cases of Leigh disease are described. In all three, symptoms began in the first months of life, with muscle hypotonia, lactic acidosis, and psychomotor delay. The diagnosis was made on the basis of the clinical characteristics, biochemical abnormalities, and typical brain magnetic resonance imaging with symmetric lesions suggesting bilateral necrosis at the level of the basal ganglia and of the midbrain. Cytochrome c oxidase (complex IV of the mitochondrial respiratory chain) deficiency was demonstrated in muscle tissue in all patients and confirmed in skin fibroblasts in patient 3. A genetic heterogeneity was present in these patients since only one had a SURF-1 gene mutation. The clinical, biochemical, and neuroradiologic aspects are discussed. Finally, the finding of facial dysmorphisms in the cytochrome c oxidase deficiency observed in one of the described cases is of extreme interest; to our knowledge, this association has never been reported in the literature.

[Large thrombus in non-aneurysmal descending aorta and peripheral embolism: report of a case and review of the literature]. / Voluminoso trombo in aorta discendente non aneurismatica ed embolia periferica: descrizione di un caso e revisione della letteratura.

We describe the case of a middle-aged woman with massive thrombosis of the aortic bifurcation, treated with emergency surgery. The patient was later evaluated by transthoracic echocardiography, which resulted normal, and by transesophageal echocardiography, which demonstrated a huge thrombus in the lumen of the descending thoracic aorta, in the absence of gross vessel wall abnormalities. Thus, the patient underwent a second surgical intervention and the thrombus was successfully removed. The episode led us to review the medical literature about cases of thrombosis and embolization originating from macroscopically normal aortas. This review underscores the diagnostic yield of the transesophageal study of the aorta in patients with systemic embolization (particularly in the presence of risk factors for atherosclerosis) and supports a wider indication of transesophageal echocardiography in the evaluation of systemic embolizating syndromes.

Midterm endothelial function and remodeling of radial artery grafts anastomosed to the aorta.

BACKGROUND: The purpose of this study was to elucidate the midterm endothelium-dependent vasodilatory capacity of radial artery grafts anastomosed to the aorta, as well as their morphometric evolution with the time. METHODS: Five years after surgery we evaluated the response of aorta-anastomosed radial artery grafts to the endovascular infusion of acetylcholine in 11 of the first 61 patients operated on at our institution, and we compared it to the response with that of internal thoracic artery grafts. Moreover, the first 20 patients who had a perfect radial artery graft on angiography at 1 year were restudied at 5 years and subjected to a comparative analysis of the diameters of the radial artery graft and the grafted coronary arteries. RESULTS: At midterm angiography, dilation of the 2 types of grafts was similar in response to acetylcholine administration (radial artery, from 2.61 +/- 0.39 to 2. 90 +/- 0.34 mm; internal thoracic artery, from 2.68 +/- 0.21 to 2.93 +/- 0.27 mm; P =.01 for both). The diameters of aorta-anastomosed radial artery grafts and grafted coronary arteries increased between both 1 and 5 years according to angiographic studies (radial artery grafts, from 2.08 +/- 0.45 to 2.54 +/- 0.53 mm; grafted coronary arteries, from 1.92 +/- 0.47 to 2.18 +/- 0.41 mm; P <.001 for both), but the increase was greater for the radial artery grafts (P <.001). CONCLUSIONS: Aorta-anastomosed radial artery grafts maintain an appreciable capacity for endothelium-dependent vasodilatation 5 years after implantation and undergo a progressive increase in luminal diameter with time. These observations contradict the presumed tendency for progressive fibrous intimal hyperplasia to develop in radial artery grafts.

MEKC of desmosine and isodesmosine in urine of chronic destructive lung disease patients.

Degradation of extracellular matrix components is central to many pathological features of chronic destructive lung disorders. Desmosine and isodesmosine are elastin-derived cross-linked amino acids whose urine levels are considered representative of elastin breakdown. The aim of this study was to apply a novel methodology, based on high-performance capillary electrophoresis, to the quantification of desmosine and isodesmosine in 11 patients with stable chronic obstructive pulmonary disease (COPD), 10 with an exacerbation of COPD, nine with alpha1-antitrypsin deficiency, 13 with bronchiectasis, and 11 adults with cystic fibrosis, in comparison to 24 controls. It was found that, in patients with stable COPD, urinary desmosine levels were higher than in controls (p=0.03), but lower than in COPD subjects with an exacerbation (p< or =0.05). The highest desmosine levels were found in subjects with alpha1-antitrypsin deficiency, bronchiectasis and cystic fibrosis (p<0.001 versus stable COPD). In a short-term longitudinal study, five stable COPD patients showed a constant rate of desmosine excretion (mean coefficient of variation <8% over three consecutive days). In conclusion, the present method is simple and suitable for the determination of elastin-derived cross-linked amino acid excretion in urine, giving results similar to those obtained using other separation methods. In addition, evidence is presented that urinary desmosine excretion is increased in conditions characterized by airway inflammation, such as exacerbations of chronic obstructive pulmonary disease, bronchiectasis and cystic fibrosis. Results obtained in subjects with alphal-antitrypsin deficiency suggest that this method might be used to evaluate the putative efficacy of replacement therapy.

Direct NAD(P)H hydrolysis into ADP-ribose(P) and nicotinamide induced by reactive oxygen species: a new mechanism of oxygen radical toxicity.

The effect of different oxygen radical-generating systems on NAD(P)H was determined by incubating the reduced forms of the pyridine coenzymes with either Fe2+-H2O2 or Fe3+-ascorbate and by analyzing the reaction mixtures using a HPLC separation of adenine nucleotide derivatives. The effect of the azo-initiator 2,2'-azobis(2-methylpropionamidine)dihydrochloride was also tested. Results showed that, whilst all the three free radical-producing systems induced, with different extent, the oxidation of NAD(P)H to NAD(P)+, only Fe2+-H2O2 also caused the formation of equimolar amounts of ADP-ribose(P) and nicotinamide. Dose-dependent experiments, with increasing Fe2+ iron (concentration range 3-180 microM) or H2O2 (concentration range 50-1000 microM), were carried out at pH 6.5 in 50 mM ammonium acetate. NAD(P)+, ADP-ribose(P) and nicotinamide formation increased by increasing the amount of hydroxyl radicals produced in the medium. Under such incubation conditions NAD(P)+/ADP-ribose(P) ratio was about 4 at any Fe2+ or H2O2 concentration. By varying pH to 2.0, 3.0, 4.0, 4.5, 5.0, 5.5, 6.0, 7.0 and 7.4, NAD(P)+/ADP-ribose(P) ratio changed to 5.5, 3.2, 1.8, 1.6, 2.0, 2.5, 3.0, 5.4 and 6.5, respectively. Kinetic experiments indicated that 90-95% of all compounds were generated within 5s from the beginning of the Fenton reaction. Inhibition of ADP-ribose(P), nicotinamide and NAD(P)+ production of Fe2+-H2O2-treated NAD(P)H samples, was achieved by adding mannitol (10-50 mM) to the reaction mixture. Differently, selective and total inhibition of ADP-ribose(P) and nicotinamide formation was obtained by performing the Fenton reaction in an almost completely anhydrous medium, i.e. in HPLC-grade methanol. Experiments carried out in isolated postischemic rat hearts perfused with 50 mM mannitol, showed that, with respect to values of control hearts, this hydroxyl radical scavenger prevented reperfusion-associated pyridine coenzyme depletion and ADP-ribose formation. On the basis of these results, a possible mechanism of action of ADP-ribose(P) and nicotinamide generation through the interaction between NAD(P)H and hydroxyl radical (which does not involve the C-center where "conventional" oxidation occurs) is presented. The implication of this phenomenon in the pyridine coenzyme depletion observed in postischemic tissues is also discussed.

Micellar electrokinetic chromatography for analyzing active site specificity of Pseudomonas aeruginosa elastase.

The geometry of the catalytic site of Pseudomonas aeruginosa elastase was reexamined, exploiting the specific feature of micellar electrokinetic chromatography (MEKC), i.e., its ability to detect a decrease of intact substrate and simultaneous formation of reaction products. We carried out a detailed investigation using two tri- and six tetra-peptide 4-nitroanilides (NA) differing from each other by only one or more amino acids as stable substrates. The kinetic cleavage parameters Km and k(cat) determined by MEKC and the catalytic efficiency Km/k(cat) values calculated allowed us to better define the substrate specificity of this proteinase.

[Remodelling of the radial artery graft 5 years after aortocoronary bypass intervention]. / Rimodellamento dei graft in arteria radiale a cinque anni dall'intervento di bypass aortocoronarico.

BACKGROUND: The radial artery (RA) is being employed as coronary artery bypass graft with good results, but when it is proximally anastomosed to the ascending aorta, undergoes substantial hemodynamic changes which could lead to significant graft intimal hyperplasia. The aim of this study was to investigate the evolution of RA graft morphology over time. METHODS: We studied 20 patients with a perfectly patent RA graft at both 1 and 5 year angiography after coronary artery bypass graft. RESULTS: Both RA graft and grafted coronary artery diameters, assessed by quantitative coronary angiography, significantly increased at 5 years, in comparison to 1 year angiography (2.08 +/- 0.45 vs 2.54 +/- 0.53 mm, +22%, p < 0.001 and 1.92 +/- 0.47 vs 2.18 +/- 0.41 mm, +13.3%, p < 0.001, respectively). CONCLUSIONS: Hemodynamic changes following RA employment for coronary artery bypass graft stimulate a remodeling of RA graft itself and of the grafted coronary arteries. The progressive increase of diameters observed in RA grafts strongly argues against the development of flow-limiting graft intimal hyperplasia when RA is proximally anastomosed to the ascending aorta. Moreover, grafted coronary artery dilation suggests that hemorrheologic changes following coronary artery bypass graft could play a major role in the development of RA remodeling over time.

[Carcinoid tumor of the appendix. A not especially rare entity]. / Il tumore carcinoide dell'appendice. Un'entità non proprio rara.

Carcinoid tumors arise from neuroendocrine system and one of their preferred sites is the appendix. Most of appendiceal carcinoids almost always are clinically silent and are incidentally found at histological examination. For this reason, histological examination of the appendix is recommended in every case of the appendicectomy. Prognostic factors are: tumor stage, histologic pattern and differentiation. The authors present 6 cases of appendiceal carcinoid tumor, clinically silent and found at histologic examination (3 cases of appendicectomy for acute appendicitis, 3 cases of appendicectomy associated with abdominal surgical interventions for other pathology) and compare their experience with the most recent literature on this subject. The conclusion is drawn that the size of this tumor is the main factor that surgeons must consider for the choice of surgical treatment. Incidental, clinical silent, small (less than 2 cm in size) appendiceal carcinoid tumors can be treated by appendicectomy, and they do not need follow-up. Greater (more than 2 cm in size) appendiceal carcinoid tumors, in young patients must be treated with a right hemicolectomy and they need follow-up (periodically radiological, ultrasonographic and endoscopic examinations, tumor markers) because there is the possibility of recurrence or metastases.

Thyroid nodules and Doppler ultrasonography. A new element for an old puzzle?

BACKGROUND: Whether Doppler ultrasonography (DU) may be of help in characterizing thyroid nodes is still under debate: both good and unsatisfactory results have been claimed, either in evaluating the presence of malignancy or in identifying hyperfunctional structures. METHODS: In this paper, the scintigraphic and Doppler patterns of 80 thyroid nodes have been compared, in the hypothesis that there may be some correlation between functional status and vascularity of the node; a small group of cyto-histological information were considered too. RESULTS: Perilesional flux seems to be, in general, somewhat more frequent than intranodal or mixed patterns: this is, however, true for all the groups of nodular functional conditions studied (peripheric flux was found in 70.2% of hyperfunctioning, 63.6% of isofunctioning and 59.3% of hypofunctioning nodes; intranodular flow was present in 18.9, 9 and 21.8% of hyper-, iso and hypofunctioning nodes respectively; mixed flow was found in 10.8% hyper, 27.2% iso and 18.7% hypofunctioning nodes). CONCLUSIONS: A prevalence of peripheric flow pattern is almost evenly distributed in all class of differently functioning nodes. Our data support the conclusion that no reliable correlations exist between scintigraphic and DU patterns: DU may not, therefore, be considered a valid substitute for nuclear imaging.

Appearance of Graves'-like disease following regression of autonomously functioning thyroid nodules. Two case reports.

Two cases are reported in which a rare hyperthyroidism appeared: in a female after radioiodine therapy for toxic multinodular goiter and in a male after spontaneous regression of a toxic adenoma. Both subjects showed a relapse of hyperthyroidism after a period of well-being lasting almost eight months in the first and three years in the second. Thyroid scans were consistent with an immunogenic hyper-thyroidism because there was a diffuse trapping of 131I in the thyroids while the previous autonomously functioning nodules became "cold". Serum TSH was undetectable, free thyroid hormones were increased, TgAb and TRAb were always normal in both patients, TPO became moderately positive only in the female. TRAb were evaluated only by radioimmunoassay. In these patients a diagnosis of Graves'-like disease was made because of the clinical and scintigraphic pattern. Moreover US did not reveal nodular areas different from those highlighted by scans. None of the subjects developed ophthalmopathy and/or dermopathy. Our remarks show that in particular subjects, genetically susceptible to autoimmunity, the release of antigenic materials secondary to destruction of thyroid nodules can trigger an autoimmune thyroid response resembling Graves' disease. Therefore all patients carrying autonomous nodules should be carefully evaluated for a possible autoimmune disposition before treatment and after admission. Radionuclide imaging is a simple, reliable, non invasive technique which can be applied in the evaluation of the etiology of the relapses.

[Diagnosis and treatment of traumatic diaphragmatic hernia with delayed presentation]. / Diagnosi e trattamento dell'ernia traumatica del diaframma a tardiva presentazione.

AIM: To evaluate the clinical picture, diagnostic techniques and most appropriate treatment in traumatic diaphragmatic hernia with delayed presentation on the basis of personal experience and in the light of other published studies. EXPERIMENTAL DESIGN: Review of cases treated. SETTING: Patients treated in University General Surgery wards. PATIENTS: Those patients in whom diagnosis was made some time after trauma and after the acute event were selected from a group of patients with traumatic diaphragmatic hernia. SURGERY: All patients underwent surgery to reduce hernia and repair the diaphragmatic lesion. MEASUREMENTS: All clinical findings were examined together with the tests performed and the type of treatment carried out. RESULTS: The diagnosis was made between 3 months and 3 years after the injury. Three patients presented manifest symptoms of high intestinal occlusion on entry. Radiological alterations were present in standard chest X-rays in all patients and digestive tract contrast radiography was positive for the diagnosis of hernia in 3 out of 4 cases in which it was performed; a preoperative diagnosis of hernia was obtained in 4 cases. Patients were operated using a thoracotomy (3 cases) or combined laparothoracotomy access (2 cases); the diaphragmatic lesion, localised in all cases in the cupula of the left hemidiaphragm, was repaired using separate sutures in non-reabsorbable material without the use of grafts. One patient died postoperatively owing to septic complications. CONCLUSIONS: traumatic diaphragmatic hernia with delayed presentation involves severe complications that increase morbidity and operating mortality.