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Biomedical subjects

A Conti

Publications and source records attributed to A Conti.

At least 73 records · Page 4Linked to original sources
PubMed2000

No increased skin reactivity in subjects with allergic rhinitis during the active phase of the disease.

Data on skin reactivity in patients with respiratory atopy without atopic dermatitis are scarce and controversial. Our purpose was to assess whether skin reactivity in patients with seasonal allergic rhinitis varies according to the phase of the disease and the possible release of inflammatory mediators acting on the skin during the pollen season. The volar forearm skin of eleven patients with seasonal allergic rhinitis without atopic dermatitis was challenged with a single exposure to sodium lauryl sulfate. The skin response was evaluated instrumentally over 72 h by transepidermal water loss, capacitance and echogenicity measurements for the assessment of skin damage and the inflammatory response. Tests were performed in winter and repeated in spring in seasonal allergic rhinitis patients, when they showed respiratory symptoms. Fifteen subjects with atopic dermatitis underwent the same experimental procedure in winter as a control population. Baseline and postexposure values were similar both in winter and in spring in seasonal allergic rhinitis patients. After sodium lauryl sulfate challenge, atopic dermatitis patients showed a higher degree of skin barrier damage and inflammation compared to patients with seasonal allergic rhinitis. These findings suggest that subjects with seasonal allergic rhinitis without atopic dermatitis have normal epidermal barrier function and normal skin reactivity during both the inactive and the active phase of the disease. Inflammatory mediators possibly released by mucous membranes during active allergic rhinitis do not influence skin barrier function.

Adult↗
PubMed2000

Protective effects of N-acetylcysteine and rutin on the lipid peroxidation of the lung epithelium during the adult respiratory distress syndrome.

This study investigates the effects of N-acetylcysteine (NAC) and rutin on the lung oxidative burden of patients with early adult respiratory distress syndrome (ARDS). The protection was evaluated by measuring expired ethane and malondialdehyde (MDA), and oxidized (GSSG) and reduced glutathione (GSH) in the epithelial lining fluid of 36 patients who developed ARDS less than 24 hours before enrollment in the study. The patients were randomly assigned to 3 groups, receiving 250 mL 5% dextrose in water (group 1), NAC 50 mg/kg body weight in 5% dextrose (group 2), and NAC 50 mg/kg + rutin 5 mg/kg in 5% dextrose (group 3). Ethane and MDA concentrations were significantly reduced in the treatment groups after day 6. GSH was 30% increased in the treatment groups. No significant variations were observed in the control group until day 9. The trial confirms that NAC and rutin are efficient in protecting the lungs of patients with ARDS.

APACHE↗
PubMed2000

Aetiologic diagnosis of ischaemic stroke in the emergency department: relevance for triage and clinical management.

Effective strategies for the aetiologic diagnosis in patients with ischaemic stroke can be implemented based on simple clinical criteria and instrumental tests which can be performed in a modern emergency room (ER) within 24 hours from admission. This may bear prognostic and therapeutic relevance for patients with acute stroke. Therefore, in this study we set out to establish the feasibility and accuracy of the aetiologic diagnosis of ischaemic stroke in an ER. A total of 136 consecutive patients (mean age 72+/-10 years, 60 females) with first ever ischaemic stroke admitted during 1996-1997 were evaluated with assessment of clinical features, CT scan, ECG, ultrasonography of the extracranial arteries, transthoracic echocardiography, and, in selected patients, transoesophageal echocardiography. Patients were classified into two major categories defined as stroke of determined origin and stroke of undetermined origin (a stroke with two or more possible causes or with a negative evaluation), according to the TOAST criteria. Ninety-six patients were considered affected by stroke of determined origin (70.5%), (22.7% with large artery atherosclerosis, 19.1% with cardioembolic stroke, 26.4% with lacunar stroke and 1.4% with other aetiology). The remaining 40 patients (29.4%) had stroke of undetermined origin: of these, 13 patients (9.5%) had a totally negative evaluation, 15 patients (12.5%) showed cardioembolism among the two or more possible causes of stroke and seven patients (5.1%) had atherothrombotic or lacunar aetiology. Additional work-up with transoesophageal echocardiography succeeded in demonstrating aortic embolism in five patients (3.6%; i.e. four patients with aortic plaques more than 4 mm in thickness and one patient with ulcerated plaques). In conclusion, the subtype classification system for ischaemic stroke allowed the aetiological diagnosis in 70.5% of patients while in the ER. Stroke of undetermined origin represented one-third of patients in a consecutive population with acute onset neurologic deficit of ischaemic origin. In approximately half of the patients with negative standard evaluation, cardiogenic or aortic arch embolic sources could be identified by transoesophageal echocardiography. Thus, the latter is indicated in patients with stroke of undetermined origin with negative first-line evaluation in order to identify embolic sources in the aortic arch.

Acute Disease↗
PubMed2000

Oncology in neuroimmunomodulation. What progress has been made?

In 1987 in Dubrovnik, Yugoslavia, N.H. Spector named a new discipline: Neuroimmunomodulation. R. Ader called this new discipline psychoneuroimmunomodulation when the major emphysis was on its behavioral aspects. Neuroimmunomodulation (NIM) is devoted to the study of the interactions at different morphologic and functional levels among the immune, nervous, and endocrine systems. In fact, this science is the modern manifestation of an old science: in the words of B.D. Jankovic (1987), "Neuroimmunomodulation is a modern reflection in neurosciences and immunosciences of the ideas and experience of philosophers and ingenious observers of ancient Egypt, Greece, China, India, and other civilizations that the mind is involved in the defense against diseases." Twelve years ago NIM was regarded by many conventional scientists almost as a form of witchcraft. Today it may be the fastest growing area of biomedical science research in the world. Important clinical applications will not be far behind. NIM research has also progressed in the field of oncology research. Topics such as treatment of hormone-dependent cancer with analogues of hypothalamic hormones, the role of opioids and T cells in cancer, stress-cancer-immune connections, the anticancer role of melatonin and cytokines, immunotherapy of cancer, and the role of psychotherapy in cancer patients represent some lines of research that have been or are being investigated by scientists. Some areas remain to be thoroughly investigated such as the influence of physical exercise (sports), music (classical or modern), and/or relaxation techniques (e.g. yoga) on the development of human cancer. This paper reviews the role of NIM in oncology and provides some perspectives for further research and development of clinical applications.

Humans↗
PubMed2000

The effect of glutathione and N-acetylcysteine on lipoperoxidative damage in patients with early septic shock.

Both the hyperproduction of oxygen free radicals (OFR) and the weakening of natural scavenging mechanisms have been implicated as contributors to multiple organ failure in septic shock. This study examined whether the antioxidants glutathione (GSH) and N-acetyl-L-cysteine (NAC) play a protective role against damage by OFR in early septic shock. We randomly entered 30 patients with septic shock into one of three groups within 24 h of diagnosis. All of the patients received septic shock therapy, including parenteral nutrition, antibiotics, and volume-expanding and inotropic agents. One group (Group B) also received 70 mg/kg/d of intravenous GSH, and a second group (Group C), 70 mg/kg/d of intravenous GSH and 75 mg/kg/d of intravenous NAC. The protection against OFR damage was evaluated by measuring expired ethane, plasma malondialdehyde, erythrocyte deformability, complement activation, and clinical scores at admission and on Days 3 and 5 of treatment. A significant decrease in peroxidative indexes was observed at Day 5 in Group B as compared with both the control group and basal values. The decrease in peroxidative indexes was even more marked in Group C. Clinical scores in this group were also significantly improved. In conclusion, the administration of high doses of NAC added to GSH significantly decreased the peroxidative stress of patients with septic shock.

APACHE↗
PubMed2000

Proteolysis of alphas-casein as a marker of Grana Padano cheese ripening.

Since casein proteolysis has a critical role in defining the typical characteristics of Grana Padano cheese, we evaluated the hydrolysis of alphas-casein during the ripening process. Thanks to the high specificity of the anti-alphas((alphas1 + alphas2)-casein monoclonal antibody and amino acid sequence determination, it was possible to identify three main alphas-casein-derived polypeptides in cheese: alphaa, alphab, and alphac. Their production by the three enzymes most involved in cheese proteolysis (pepsin, chymosin, and plasmin) was evaluated by performing in vitro digestions. Data showed that alphaa was released in cheese mainly by the chymosin attack, while alphab and alphac were due to the action of plasmin. A significant correlation between the abundance of some polypeptides and ripening process was shown.

Amino Acid Sequence↗
PubMed1999

Posterior fusion and implantation of the SOCON-SRI system in the treatment of adult spondylolisthesis.

Surgery for adult patients with lumbar and lumbosacral spondylolisthesis is reserved for those with intractable radiculopathy, claudication, or symptomatic spinal instability. Internal fixation, in which posterior fusion, transpedicular screw fixation, and implantation of titanium devices are performed, has been advocated to improve fusion rates and clinical results. Fourteen consecutive patients with Grade II to III lumbar and lumbosacral spondylolisthesis who underwent posterior decompression, reduction, autologous posterior facet joint arthrodesis, and SOCON-SRI implantation are retrospectively reviewed. All patients underwent complete preoperative clinical and neuroradiological evaluation. Treatment consisted of posterior decompressive surgery and implantation of the SOCON-SRI system (transpedicular screws, prebent longitudinal rods, and one locking-screw clamps). Distraction of the interbody space and rotation were performed to achieve an optimum spinal realignment. The facet joints were fused by using autologous bone graft. The authors obtained detailed clinical, functional, economic, and neuroradiological follow-up data for up to 14 months (range 8-18 months). The efficacy of the treatment was evaluated by comparing pre- and postoperative data. Pain was decreased in all cases, neurological dysfunction ameliorated in 50%, and functional and economic status was improved in 78% and 100%, respectively. No cases of fusion failure or instrumentation-related complications occurred. The authors describe their results of treating patients with spondylolisthesis in the light of the rationale for surgery and the more recent pertinent literature.

Journal Article↗
PubMed1999

Deletion of the ryanodine receptor type 3 (RyR3) impairs forms of synaptic plasticity and spatial learning.

Deletion of the ryanodine receptor type 3 (RyR3) results in specific changes in hippocampal synaptic plasticity, without affecting hippocampal morphology, basal synaptic transmission or presynaptic function. Robust long-term potentiation (LTP) induced by repeated, strong tetanization in the CA1 region and in the dentate gyrus was unaltered in hippocampal slices in vitro, whereas weak forms of plasticity generated by either a single weak tetanization or depotentiation of a robust LTP were impaired. These distinct physiological deficits were paralleled by a reduced flexibility in re-learning a new target in the water-maze. In contrast, learning performance in the acquisition phase and during probe trial did not differ between the mutants and their wild-type littermates. In the open-field, RyR3(-/-) mice displayed a normal exploration and habituation, but had an increased speed of locomotion and a mild tendency to circular running. The observed physiological and behavioral effects implicate RyR3-mediated Ca(2+) release in the intracellular processes underlying spatial learning and hippocampal synaptic plasticity.

Animals↗
PubMed1999

Type 3 and type 1 ryanodine receptors are localized in triads of the same mammalian skeletal muscle fibers.

The type 3 ryanodine receptor (RyR3) is a ubiquitous calcium release channel that has recently been found in mammalian skeletal muscles. However, in contrast to the skeletal muscle isoform (RyR1), neither the subcellular distribution nor the physiological role of RyR3 are known. Here, we used isoform-specific antibodies to localize RyR3 in muscles of normal and RyR knockout mice. In normal hind limb and diaphragm muscles of young mice, RyR3 was expressed in all fibers where it was codistributed with RyR1 and with the skeletal muscle dihydropyridine receptor. This distribution pattern indicates that RyR3 is localized in the triadic junctions between the transverse tubules and the sarcoplasmic reticulum. During development, RyR3 expression declined rapidly in some fibers whereas other fibers maintained expression of RyR3 into adulthood. Comparing the distribution of RyR3-containing fibers with that of known fiber types did not show a direct correlation. Targeted deletion of the RyR1 or RyR3 gene resulted in the expected loss of the targeted isoform, but had no adverse effects on the expression and localization of the respective other RyR isoform. The localization of RyR3 in skeletal muscle triads, together with RyR1, is consistent with an accessory function of RyR3 in skeletal muscle excitation-contraction coupling.

Aging↗
PubMed1999

Long-term monitoring of rec-GH treatment by serial determination of serum aminoterminal propeptide of type III procollagen in children and adults with GH deficiency.

Serum aminoterminal propeptide of type III procollagen (PIIINP) levels, a reliable marker of collagen formation, were evaluated in children (C=7) and adults with childhood-onset (CO=10) and acquired (A=18) GH deficiency (GHD) before, during and after withdrawal of rec-GH therapy (C=0.6 IU/kg/week, CO=0.5 IU/kg/week, A=0.25 IU/kg/week). The duration of treatment was 12 months for C and A and 6 months for CO; investigations were carried out before and at 3, 6, 9 and 12 months (for C and A) and at 3 and 6 months (for CO) of GH treatment and 6 months after the withdrawal of therapy (for A and CO). Data obtained from patients were compared with those recorded in two age- and sex-matched control groups. Before treatment, serum PIIINP levels were significantly lower (p<0.001) in C with GHD (mean+/-SE: 2.9+/-0.4 ng/ml) than in controls (6.1+/-0.4 ng/ml), while no significant differences were recorded between adults with CO/A-GHD (3.7+/-0.5 ng/ml and 3.4+/-0.2 ng/ml) and controls (3.2+/-0.2 ng/ml). GH treatment caused a significant increase (p<0.0001) of PIIINP levels both in C (3rd month: 4.4+/-0.2 ng/ml, 6th month: 5.1+/-0.4 ng/ml, 12th month: 5.1+/-0.5 ng/ml), CO-GHD (3rd month: 12.7+/-1.2 ng/ml; 6th month: 10.2+/-0.6 ng/ml) and A-GHD (3rd month: 10.0+/-1.0 ng/ml; 6th month: 8.4+/-0.6 ng/ml; 12th month: 7.0+/-0.7 ng/ml), the increase being dose-dependent (more marked and sustained in adults with CO-GHD). The maximal stimulation of collagen synthesis occurred after 3 months of GH treatment in adults with GHD, while a more gradual and less relevant increase was observed in C with GHD. Six months after the withdrawal of GH therapy, serum PIIINP levels of adults with CO-GHD (3.6+/-0.3 ng/ml) were similar to those recorded before treatment, while in adults with A-GHD serum PIIINP levels (2.6+/-0.2 ng/ml) were significantly lower (p<0.01) than in basal condition. In conclusion, our study shows that: a) GHD is associated with a reduction of soft tissue formation in children, while it seems to exert no relevant effects in adults with GHD; b) GH therapy causes a rapid stimulation of collagen turnover, which shows a different pattern in children and adults; c) the GH-induced stimulation of collagen synthesis is rapidly removed after the withdrawal of GH treatment. For these reasons, the determination of peripheral markers of GH effects appears useful for the monitoring of GH therapy and can contribute to assess the "tailored" substitutive dose for the individual patient.

Adolescent↗
PubMed1999

Clinical role of a lipid transfer protein that acts as a new apple-specific allergen.

BACKGROUND: Allergy to apple is commonly associated with birch pollinosis because the two share homologous allergens. However, some patients have apple allergy but no birch pollinosis, suggesting that there are allergens that do not cross-react with birch. OBJECTIVE: The aim of the study was to evaluate the IgE reactivity pattern to an apple extract in subjects with allergic reactions to apple, with and without birch hay fever. METHODS: Forty-three patients with oral allergy syndrome for apple and positive open food challenge, skin prick test, and serum specific IgE antibodies to apple were admitted to the study. Thirty-two had birch pollinosis (documented by specific IgE for birch) and 11 were not allergic to birch. The IgE reactivity pattern to apple extract was identified by SDS-PAGE and immunoblotting. The consistent allergen, a 9-kd protein, was then purified by HPLC and characterized by periodic acid-Schiff staining, isoelectric point, and N-terminal amino acid sequencing. RESULTS: The sera from 28% of patients allergic to apple with birch pollinosis, but from all patients allergic only to apple, recognized the 9-kd protein. This protein has an isoelectric point of 7.5 and is not glycosylated. Determination of its partial amino acid sequence showed that it belongs to the family of lipid transfer proteins, which act as major allergens in Prunoideae fruits. CONCLUSIONS: These results indicate that a lipid transfer protein is an important allergen in patients allergic to apple but not to birch pollen. The prevalent IgE reactivity to this allergen in subjects with no birch pollinosis and the physicochemical characteristics of this protein suggest that sensitization may occur through the oral route.

Adolescent↗
PubMed1999

The major allergen of peach (Prunus persica) is a lipid transfer protein.

BACKGROUND: Allergy to fresh fruits and vegetables is mostly observed in subjects with pollinosis, especially from birch, because of cross-reacting allergens in vegetable foods and pollens. However, allergic reactions to fruits, specifically Rosaceae fruits, have been reported in subjects without pollinosis. OBJECTIVE: This study evaluated the pattern of IgE reactivity, identifying the allergen responsible in 2 groups of patients with oral allergy syndrome to peach with or without birch pollinosis. METHODS: The allergenic components of peach were detected by SDS-PAGE and immunoblotting. The major peach allergen was purified by HPLC with a cation-exchange column followed by gel filtration chromatography. Its IgE-binding capacity and its homology with the protein of the crude extract were demonstrated by immunoblotting inhibition techniques. To better characterize this allergen, periodic acid-Schiff stain and isoelectrofocusing were used. The amino acid sequencing was done with a gas-phase sequencer. RESULTS: SDS-PAGE and immunoblotting of the 15 patients allergic to peach, 8 without and 7 with birch pollinosis, showed that they all recognized a protein with a molecular weight of 9 kd. This was the only allergen recognized by patients not sensitized to pollen, whereas the birch pollen-sensitive patients had IgE binding to other allergenic proteins at higher molecular weights. The purified 9-kd protein retained its IgE-binding capacity, was negative to periodic acid-Schiff stain, and had an isoelectric point value of greater than 9. A search in the Swiss Prot Bank showed this was a lipid transfer protein, belonging to a group of molecules involved in the defensive system of plants. CONCLUSIONS: The major allergen of peach is a 9-kd protein belonging to the group of lipid transfer proteins. This is the only allergen recognized by patients allergic to peach but not sensitized to birch pollen.

Adolescent↗
PubMed1999

Double-blind randomized study on the myeloprotective effect of melatonin in combination with carboplatin and etoposide in advanced lung cancer.

A significant myeloprotective effect of melatonin in mice treated with etoposide, cyclophosphamide or carboplatin has been reported. The present study was designed to evaluate if the same effect could be observed in patients receiving chemotherapy. Twenty previously untreated patients with inoperable lung cancer received two cycles of carboplatin (given at area under the curve 5 by the Calvert formula) on day 1 and etoposide (150 mg m(-2) i.v.) on days 1-3 every 4 weeks. Melatonin 40 mg or placebo (double-blind) was given orally in the evening for 21 consecutive days, starting 2 days before chemotherapy. Patients were randomized to receive melatonin either with the first or the second cycle. Complete blood cell count with differential was done three times per week for 3 weeks. The median age of the cohort was 60 years (range 42-69), 16 patients had non-small cell and four patients small-cell lung cancer, 12 stage III and eight stage IV disease. In a multivariate analysis including age, sex, diagnosis, stage, performance status, doses of carboplatin and etoposide, and concomitant treatment with melatonin or placebo, the haematological parameters--depth and duration of toxicity for haemoglobin, platelets and neutrophils (ANC)--were not significantly different between cycles with/without melatonin. The mean ANC nadir and the mean number of days with ANC < 0.5 x 10(9) l(-1) were 0.5 x 10(9) l(-1) and 2.5 days, respectively, with/without melatonin. We concluded that, in patients with lung cancer, melatonin given orally at a dose of 40 mg per day for 21 days in the evening, does not protect against the myelotoxic effect of carboplatin and etoposide.

Adult↗
PubMed1999

The impact of gender, puberty and body mass on reference values for urinary growth hormone (GH) excretion in normally growing non-obese and obese children.

OBJECTIVE: There is a lack of normal reference data on urinary GH (u-GH) excretion in children. We have investigated the impact of age, gender, pubertal development and body mass on reference values for u-GH excretion in normally growing non-obese and obese children. STUDY DESIGN: u-GH levels were evaluated in 1153 healthy normal children (aged 5-14) and in 684 obese children (body mass index, BMI: > 75th). u-GH levels (ng/8 h) were determined by ELISA as the mean value of three consecutive first morning voidings. RESULTS: Reference values (5-95th centile) for u-GH excretion in obese and non-obese children of both sexes are reported. In normal prepubertal children median u-GH levels were relatively stable and superimposable in the two sexes; subsequently, u-GH levels increased, reaching a peak value at 13 years in both sexes. Significant increments (P < 0.0001) in u-GH levels were shown at B2 for females and at G3 for males. A slight decline was evident at 14 years. In obese children, median u-GH concentrations were significantly lower than those recorded in normal children of prepubertal age and at all stages of puberty (except in females at B2), in spite of their comparable normal height. u-GH levels significantly increased at puberty also in obese children, although the pubertal rise was significantly (P < 0.001) lower (1.7-fold in both sexes) than that observed in normal children (2.5-fold in boys and 2.3-fold in girls). A multiple regression analysis showed that both chronological age (beta: 0.20), BMI (beta: - 0.11), gender (beta: - 0.04) and pubertal stage (beta: 0.25) contributed significantly to the physiological variation in u-GH levels (multiple R: 0.44, P < 0.00001). CONCLUSIONS: This study provides reference values for u-GH in normally growing non-obese and obese children, analysing the impact of gender, puberty and body mass on this parameter. In agreement with previous studies, which demonstrate blunted GH-responses to provocative stimuli and reduced nocturnal GH concentration, obese children have significantly lower u-GH levels than age-matched normal weight children, both before and during puberty.

Adolescent↗
PubMed1999

P48 major surface antigen of Mycoplasma agalactiae is homologous to a malp product of Mycoplasma fermentans and belongs to a selected family of bacterial lipoproteins.

A major surface antigenic lipoprotein of Mycoplasma agalactiae, promptly recognized by the host's immune system, was characterized. The mature product, P48, showed significant similarity and shared conserved amino acid motifs with lipoproteins or predicted lipoproteins from Mycoplasma fermentans, Mycoplasma hyorhinis, relapsing fever Borrelia spp., Bacillus subtilis, and Treponema pallidum.

Amino Acid Motifs↗
PubMed1999

Complete amino acid sequence determination of the major allergen of peach (Prunus persica) Pru p 1.

The major protein allergen of peach (Prunus persica), Pru p 1, has recently been identified as a lipid transfer protein (LTP). The complete primary structure of Pru p 1, obtained by direct amino acid sequence and liquid chromatography-mass spectrometry (LC-MS) analyses with the purified protein, is described here. The protein consists of 91 amino acids with a calculated molecular mass of 9178 Da. The amino acid sequence contains eight strictly conserved cysteines, as do all known LTPs, but secondary structure predictions failed to classify the peach 9 kDa protein as an 'all-alpha type', due to the high frequency of amino acids (nine prolines) disrupting alpha helices. Although the sequence similarity with maize LTP is only 63%, out of the 25 amino acids forming the inner surface of the tunnel-like hydrophobic cavity in maize ns-LTP 16 are identical and 7 similar in the peach homolog, supporting the hypothesis of a similar function.

Allergens↗