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G Arpaia

Publications and source records attributed to G Arpaia.

At least 19 recordsLinked to original sources

Incidence of first-ever ischemic and hemorrhagic stroke in a well-defined community of southern Italy, 1993-1995.

Most epidemiological surveys in the Italian population, have concentrated on areas of northern and central Italy. The incidence of the first-ever ischemic and hemorrhagic strokes in a well-defined population of the province of Foggia, a rural area of southern Italy, over a 3-year period has been investigated, to compare the occurrence of stroke by type in this and other areas. A retrospective study in a local health district (USL FG3) in the province of Foggia was conducted and all cases of first-ever cerebral infarction (CI) and intracerebral hemorrhage (ICH) in the local population (41 269) from January 1, 1993 to December 31, 1995 have been investigated. Case ascertainment was performed by a chart review in the two local hospitals and examination of death certificates. General practitioners were also asked to report on non-hospitalized cases suffering a stroke during the study period. Patients with recurrent stroke, unclassifiable stroke, transient ischemic attacks and subarachnoid hemorrhage were excluded. Risk factors for stroke and 30-day mortality were investigated. The rates were standardized to the Italian population (57 138 489, 1991 census). During the 3-year study period, 202 patients had a first-ever ischemic or hemorrhagic stroke (66 in 1993, 69 in 1994 and 67 in 1995). Of these, 174 (86.1%) had cerebral ischemia, accounting for 57, 60 and 57 cases in the three index years. The overall crude annual incidence of CI and ICH was 1.60, 1.67 and 1.62 of 1000 for 1993, 1994 and 1995, respectively. The corresponding standardized incidences rates were 2.0, 2.10 and 2.06 of 1000. The rate was 0.11 in patients <55 years of age, and 1.97, 7.01, 13.52, and 25.34 at ages 55-64, 65-74, 75-84, and 85+ years for the entire period; the 30-day mortality was 27.2, 21.7, and 15% for 1993, 1994, and 1995, respectively. Hypertension (45.9%), diabetes (26.4%) and atrial fibrillation (16.6%) were the most common risk factors. The incidence of CI and ICH was similar to that of most other Italian studies. It was constant during the 3-year period, and mostly involved older people.

Aged↗

Involvement of protein kinase C in the response of Neurospora crassa to blue light.

As a first step towards understanding the process of blue light perception, and the signal transduction mechanisms involved, in Neurospora crassa we have used a pharmacological approach to screen a wide range of second messengers and chemical compounds known to interfere with the activity of well-known signal transducing molecules in vivo. We tested the influence of these compounds on the induction of the al-3 gene, a key step in light-induced carotenoid biosynthesis. This approach has implicated protein kinase C (PKC) as a component of the light transduction machinery. The conclusion is based on the effects of specific inhibitors (calphostin C and chelerythrine chloride) and activators of PKC (1,2-dihexanoyl-sn-glycerol). During vegetative growth PKC may be responsible for desensitization to light because inhibitors of the enzyme cause an increase in the total amount of mRNA transcribed after illumination. PKC is therefore proposed here to be an important regulator of transduction of the blue light signal, and may act through modification of the protein White Collar-1, which we show to be a substrate for PKC in N. crassa.

Adaptation, Physiological↗

The tbf-1 gene from the white truffle Tuber borchii codes for a structural cell wall protein specifically expressed in fruitbody.

This paper reports the purification and localization of a Tuber borchii Vittad, fruitbody protein (TBF-1) and the cloning of the encoding gene. TBF-1 is detectable by SDS-PAGE analyses only in this white truffle species and presents a molecular mass of 11,994 Da. TBF-1 was purified by one-step Reversed-Phase HPLC and its complete amino acid sequence was determined after digestion with trypsin and N-Asp endoproteinase. Polyclonal antibodies were produced and tested in immunofluorescence and immunogold experiments, providing information about the protein localization. It was detected mostly on the hyphal walls, where it was colocalized with beta-1,3-glucans and chitin. The sporal wall was not labeled. The encoding gene (tbf-1) was cloned using several techniques involving PCR. The coding region consists of a 360-bp open reading frame interrupted by an intron, with another intron following the stop codon. A putative signal peptide of 12 amino acids was found at the N-terminal. Northern blot analysis revealed that tbf-1 is highly expressed in unripe and ripe fruitbodies and was not detectable in culture mycelium or ectomycorrhizal roots.

Amino Acid Sequence↗

Levels of the inhibitor of PMN-elastase in venous blood reflowing from chronically affected veins: the role of venous stasis.

BACKGROUND: Attention has recently been paid to the cell and biochemical disorders involved in chronic venous insufficiency (CVI) and to their possible relationship to the endothelium. METHODS: In the present study, carried out in 14 patients with CVI, we evaluated the levels of the inhibitor of elastase (I-EL) generated by polymorphonucleate cells in the blood reflowing from affected superficial veins of legs both at rest and after prolonged venous stasis (1 hour in standing position). RESULTS: We evaluated the I-EL both as percentage of activity (baseline 82.3+/-24.5%; after stasis 100.7+/-37.8%) and as absolute values (0.67+/-0.26 U/ml; after stasis 0.79+/-0.39 U/ml). In blood samples taken after venous stasis we found a tendency toward a trapping of white blood cells and an increase of the haematocrit over baseline. The difference in the percentages of activity of I-EL was statistically significant, but only a trend was observed for the absolute values. CONCLUSIONS: We believe that the typical haemodynamic disorders of patient with CVI increased by prolonged venous stasis can modify the function of white blood cells, which are closely linked with venous hypertension, thus playing an important role in the pathogenesis of skin ulcers.

Enzyme-Linked Immunosorbent Assay↗

Fibrinolytic response in subjects with hypertriglyceridemia and low HDL cholesterol.

The combination of hypertriglyceridemia and low high-density lipoprotein cholesterol (HDL-C) appears to be an excessively high risk factor for coronary artery disease (CAD). In the Helsinki study, both coronary events and mortality were decreased by gemfibrozil, especially in subjects with low HDL-C and high triglycerides (TG). On the other hand, it is known that high levels of TG can be associated with high levels of circulating plasminogen activator inhibitor (PAI), which is also a possible risk factor for CAD. The aim of the present study was to see: 1) whether the combination of low HDL-C and high TG is associated with a more impaired fibrinolytic response than in either isolated condition, and 2) whether gemfibrozil administration can improve fibrinolysis in patients with both high TG and low HDL-C. Twelve non-obese, non-diabetic subjects (eight men, four women; mean age 55 +/- 13 yrs) with low HDL-C (< 35 mg/dL men; < 45 mg/dL women) and high TG (mean 253.6 +/- 42.6 mg/dL) entered the study (Group A). Additionally fourteen comparable subjects with normal HDL-C were also investigated (Group B), plus 12 comparable subjects with isolated low HDL-C (Group C). Ten healthy people served as the control group. The following plasma fibrinolytic parameters were measured: tissue plasminogen activator antigen, PAI antigen and activity, euglobulin fibrinolytic activity (EFA) on fibrin plates, plasminogen and alpha-2-antiplasmin activities. All except the latter two values were also measured after venous occlusion (vo). In baseline conditions, patients in Groups A and B had higher EFA values before vo and higher PAI-1 antigen and alpha-2-antiplasmin levels after vo than those of controls or the subjects in Group C. The relationship between PAI antigen and PAI activity and TG was not confirmed in our population (n = 48). We also saw no interference due to HDL-C, while there was a significant relationship between EFA before vo and both TG and cholesterol. After gemfibrozil treatment (600 mg bid for 12 weeks), the lipid profiles of subjects with high TG and low HDL-C were significantly improved. There was also a slight reduction of PAI activity after vo, while the PAI-1 antigen had decreased significantly from baseline after vo (56.3 +/- 13 ng/mL before vo; 48.4 +/- 21 ng/mL after vo; P = 0.04). The higher risk of CAD in patients with low HDL-C and high TG might be in part related to impairment of fibrinolysis, which occurs in patients with isolated high TG. The close relationship existing between both TG and cholesterol levels and fibrinolytic activity confirm the key role of this latter process in the development of CAD.

Aged↗

Effects of two different HMG-CoA reductase inhibitors on thromboxane production in type IIA hypercholesterolemia.

Many studies have found that familial hypercholesterolemia, a hyperlipoproteinemia associated with premature atherosclerosis, is characterized by enhanced platelet aggregation. This study was undertaken to measure the urinary excretion of the two main urinary thromboxane B2 (TXB2) metabolites (2, 3-dinor-TXB2 and 11-dehydro-TXB2) in 20 patients affected by familial hypercholesterolemia treated for one month with 40 mg/day of pravastatin (10 patients) in comparison to 10 normocholesterolemic subjects. After a run-in period, the type II A patients showed total cholesterol levels (296 +/- 32 mg/dL) significantly higher (P < 0.001) than those of control subjects (155 +/- 46 mg/dL). The urinary concentrations of 11-dehydro-TXB2 and 2,3-dinor-TXB2 also significantly differed (P < 0.001) between control group (1,463 +/- 1,440 and 386 +/- 447 pg/mg urinary creatinine) and treated patients (3,536 +/- 2,112 and 914 +/- 572 pg/mg urinary creatinine). At baseline there was a positive correlation between total cholesterol (TC) levels and urinary TXB2 metabolite concentrations (2,3-dinor-TXB2 r = 0.61, P < 0.02; 11-dehydro-TXB2, r = 48, P < 0.05), but not between low-density-lipoprotein cholesterol (LDL-C) and the urinary compounds. At the end of a four-week treatment. TC and LDL-C had decreased significantly from the baseline levels, by 27% and 30% in the fluvastatin group (P < 0.01) and by 23% and 31% in the pravastatin group (P < 0.01), with no significant difference between the two groups. After the two treatments with HMG-CoA reductase inhibitors, there was no statistically significant reduction of the urinary metabolite levels. In addition, the positive correlation seen at baseline between TC and TXB2 metabolites was no longer present. In accord with previous studies, we found a significant correlation between TC levels and TXB2 metabolites concentrations in type II A hypercholesterolemic patients. Although, short-term treatment with two statins reduced TC levels, it did not change the thromboxane metabolite excretion.

Anticholesteremic Agents↗

Effects of fluvastatin and pravastatin on lipid profiles and thromboxane production in type IIa hypercholesterolemia.

The aim of this study was to assess the effects of fluvastatin and pravastatin on lipid profiles and urinary thromboxane (TX) A2 metabolites (11-dehydro TXB2 and 2,3-dinor TXB2) in patients with type IIa hypercholesterolemia. A total of 20 patients (13 men, 7 women; mean age 53 +/- 9 years) with primary type IIa hypercholesterolemia (Fredrickson's classification) in a 4-week, double-blind, parallel-group study were randomized to fluvastatin or pravastatin, both at 40 mg once daily (at bedtime), after a single-blind, 4-week, placebo run-in period. Total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), and triglycerides were measured after placebo (baseline) and after 4 weeks of double-blind treatment. Thromboxane metabolites were measured at the same time points, using an enzyme immunoassay kit, in 12 hr urine samples. At baseline, the mean +/- SD levels of total cholesterol, LDL-C, triglycerides, and HDL-C were: 292 +/- 23, 213 +/- 47, 186 +/- 119 and 41 +/- 17 mg/dL with fluvastatin; and 301 +/- 40, 212 +/- 40, 150 +/- 124 and 43 +/- 10 mg/dL with pravastatin, respectively. Baseline thromboxane-metabolite levels were positively and significantly (p < 0.04) correlated with levels of total cholesterol, but not LDL-C. Compared with baseline, total cholesterol and LDL-C were significantly (p < 0.01) decreased by 27% and 30% with fluvastatin, and by 23% and 31% with pravastatin, respectively. HDL-C increased from 41 +/- 17 to 59 +/- 25 mg/dL with fluvastatin, and from 43 +/- 10 to 46 +/- 12 mg/dL with pravastatin.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticholesteremic Agents↗

Light induction of the clock-controlled gene ccg-1 is not transduced through the circadian clock in Neurospora crassa.

Ambient light and the circadian clock have been shown to be capable of acting either independently or in an interrelated fashion to regulate the expression of conidiation in the ascomycete fungus Neurospora crassa. Recently several molecular correlates of the circadian clock have been identified in the form of the morning-specific clock-controlled genes ccg-1 and ccg-2. In this paper we report studies on the regulation of ccg-1, an abundantly expressed gene displaying complex regulation. Consistent with an emerging consensus for clock-controlled genes and conidiation genes in Neurospora, we report that ccg-1 expression is induced by light, and show that this induction is independent of the direct effects of light on the circadian clock. Although circadian regulation of the gene is lost in strains lacking a functional clock, expression of ccg-1 is still not constitutive, but rather fluctuates in concert with changes in developmental potential seen in such strains. Light induction of ccg-1 requires the products of the Neurospora wc-1 and wc-2 genes, but surprisingly the requirement for wc-2 is suppressed in conditional mutants of cot-1, a gene that encodes, a cAMP-dependent protein kinase. These data provide insight into a complex regulatory web, involving at least circadian clock control, light control, metabolic control, and very probably developmental regulation, that governs the expression of ccg-1.

Blotting, Northern↗

Light and development regulate the expression of the albino-3 gene in Neurospora crassa.

The albino-3 gene of Neurospora crassa codes for geranylgeranyl pyrophosphate synthase, an enzyme involved in the biosynthesis of carotenoids. The albino-3 locus encodes two overlapping transcription units that give rise to two mRNAs of 2.2 kb (al-3(c)) and 1>6 kb (al-3(m)), with the promoter of the latter residing in the transcribed region of the former. The 1.6-kb transcript was transiently expressed in the mycelium after light induction, while the 2.2-kb mRNA appeared in conidiating cultures only, independently of light. Al-3(c) mRNA was enhanced in the conidiophores and was impaired in mutants blocked at the early stages of conidiation; al-3(c) therefore represents a conidiation-specific transcript. The al-3(c) mRNA level increased upon illumination with blue light and fluctuated according to the circadian cycle.

Base Sequence↗

Platelet-derived growth factor (PDGF) in patients with different degrees of chronic arterial obstructive disease.

Platelet activation and platelet-derived growth factor (PDGF) play a pivotal role in the pathogenesis of atherosclerosis. Evidence has been accumulating that in the evolution of chronic arterial obstructive disease (CAOD) platelets are also crucially important. The aim of the present study was, therefore, to assess plasma levels of PDGF in patients with different degrees of CAOD according to Fontaine. Twenty patients (17 men, 3 women, mean age sixty-eight +/- seven years) with intermittent claudication (Fontaine stage II) entered the study and their PDGF levels were assessed by radioimmunoassay. Ten additional patients (7 men, 3 women, mean age seventy-three +/- seven years) with more severe CAOD (leg pain at rest/skin ulcers) were also studied. Ten healthy subjects (6 men, 4 women, mean age fifty-four +/- six years) comprised the control group. Patients in stage II were reinvestigated after sixty days of a "training" procedure. Patients with both intermittent claudication and more severe disease had higher levels of PDGF than controls (controls 165.9 +/- 119.1 pg/mL; Fontaine stage II 403.5 +/- 218.4; Fontaine stage III/IV 578.1 +/- 637.2: ANOVA P = 0.04) with no difference between the two groups of patients. After the training period, PDGF levels were significantly higher than at baseline (863.7 +/- 819.6 pg/mL vs 403.5 +/- 218.4) but without significant improvement of physical performance. The elevation of PDGF levels in blood from CAOD patients could be the result of marked platelet activation due to interaction with a widely damaged peripheral vasculature. The same was not true for coronary heart disease, in which normal values of PDGF in venous blood were found.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Plasma levels of tumor necrosis factor and endothelial response in patients with chronic arterial obstructive disease or Raynaud's phenomenon.

Tumor necrosis factor alpha (TNF-alpha) is a cytokine that affects endothelial cells' function by changing their antithrombotic potential to a net procoagulant effect. Only a few data have so far been reported for the pathophysiologic role of TNF in vascular diseases in the involvement of microvessels and/or macrovessels and a prothrombotic state. In the present study the authors evaluated plasma TNF (and interleukin-1) levels in 20 patients with chronic arterial obstructive disease (CAOD) with intermittent claudication and 10 CAOD patients with more severe disease (pain at rest/skin ulcers). In addition, they studied 10 patients with Raynaud's phenomenon (RP), suspected to be secondary to a collagen disease. The control group consisted of 20 subjects matched for sex and age with the three groups of patients. TNF levels were assayed by enzyme-linked immunosorbent assay. The antigen levels of von Willebrand factor (vWF), tissue plasminogen activator (t-PA), and its inhibitor (PAI) were also determined as markers of release from the endothelium, while the fragment 1 + 2 of prothrombin (F1 + 2) and thrombin-antithrombin III (TAT) complexes were assessed as indexes of systemic thrombin generation. TNF levels were significantly higher in both groups of CAOD patients than in controls or RP patients, and the same was true for vWF. t-PA was significantly higher only in the CAOD subjects with more severe disease. No differences among groups were seen in PAI antigen/activity or thrombin generation. When data were corrected for age, TNF no longer differentiated CAOD patients from controls and RP subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Platelet and endothelial response with trapidil in patients with peripheral obliterative arteriopathy.

The activity of trapidil, an antiaggregating agent with PDGF antagonist properties, was investigated in order to verify its possible modulating effect in the endothelial and platelet activation. PDGF, t-PA, PAI-1 and ET-1 plasma levels were measured before and after a 2 month treatment period with trapidil 200 mg tablets bid or placebo in 30 patients affected by POA in Fontaine stage II. PDGF and PAI-1 significantly (p < 0.05) increased in the placebo group, and PDGF also in the comparison between treatments (p < 0.05). Aggregation data demonstrate an absence of Ca++ antagonist action of trapidil. The results of this study suggest that trapidil can interfere with the combined vascular and platelet response in atherogenesis.

Aged↗

Need to expand microvascular investigation of patients with Raynaud's phenomenon of different etiology: clinical patterns of 106 consecutive patients.

The differential diagnosis of Raynaud's Phenomenon (RP) is still problematic because of the wide variety of underlying etiological possibilities. Therefore, the diagnostic screening of patients requires easily reproducible, rapid and reliable tests to find those cases of RP secondary to a connective tissue disorder. The present study of 106 consecutive RP patients was carried out by using a combination of clinical examination, biomicroscopy of fingernail folds and bulbar conjunctiva (with scoring of vascular damage), plus the assessment of antinuclear antibodies on HEP2 cells. On the basis of the reported findings, it can be concluded that patients with RP secondary to collagen disease or so suspected also show abnormalities of the conjunctival microcirculatory bed. Patients with both primary and suspected secondary RP are significantly younger at the time of first diagnosis than patients with collagen disease-associated RP.

Adult↗

Structural characterization of a biologically active human lipocortin 1 expressed in Escherichia coli.

Lipocortin or annexin 1 is a calcium-dependent phospholipid-binding protein which probably acts as a glucocorticoid- regulated anti-inflammatory factor. cDNA for human lipocortin 1 was cloned in the pT7.7 expression plasmid under the control of the inducible bacteriophage T7 RNA polymerase promoter. Upon induction with isopropyl thio-beta-D-galactoside, large amounts of the protein were produced and accumulated in Escherichia coli in a soluble form. The recombinant protein was purified to homogeneity by means of two subsequent ion-exchange chromatographic steps. The final yield was about 30 mg/l bacterial culture. Electrospray mass spectrometric analysis of the purified protein demonstrated that the recombinant product corresponds to the native human lipocortin 1, without the initial methionine and with a free N-terminal alanine; tryptic peptide mapping by fast-atom-bombardment mass spectrometry showed that the recombinant protein contains cysteine residues at positions 263 and 324 with free thiol groups, whereas Cys270 and Cys343 are probably involved in an intrachain disulfide bridge. Recombinant human lipocortin 1 reduces the carrageenin-induced paw oedema in rat in vivo and inhibits porcine pancreatic phospholipase A2 activity in vitro; in both cases, a dose-related response is observed.

Amino Acid Sequence↗