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Biomedical subjects

F Lombardo

Publications and source records attributed to F Lombardo.

At least 73 records · Page 4Linked to original sources
PubMed1999

Factors affecting diabetes mellitus onset in cystic fibrosis: evidence from a 10-year follow-up study.

This study reports the results of genotype characterization and of a 10-y prospective evaluation of clinical status, glucose tolerance and insulin secretion in 28 originally normoglycaemic patients with cystic fibrosis (CF). The aim of the study was to assess whether any genetic, clinical or metabolic parameters could identify in advance those patients at risk of developing diabetes mellitus over time. During the follow-up 42.8% of patients became diabetic. Neither gender, age nor clinical parameters were significantly different at entry in the patients who eventually developed diabetes compared with those who did not. Insulin secretion during oral glucose tolerance tests (OGTT) deteriorated over time in both groups, whereas a progressive deterioration of glucose tolerance was only evident in the patients who developed diabetes and increased baseline glucose areas were the only predictive parameter of diabetes onset. Genotype analysis revealed significant differences between patients with and without diabetes: deltaF508 homozygosis was more frequent in the first group and N1303K mutation in the second group. In conclusion, in CF: (i) increased glucose areas during OGTT and deterioration of glucose tolerance over time can predict the evolution towards diabetes; and (ii) deltaF508 homozygosis may predispose to the risk of diabetes, whilst N1303K mutation seems to play a protective role.

Adolescent↗
PubMed1999

Immature germ cell separation using a modified discontinuous Percoll gradient technique in human semen.

The difficulty of identifying immature germ cells in unstained, fresh semen has led most laboratories to use the broad definition 'round cells' to indicate cells other than spermatozoa, thus grouping together both leukocytes and immature germ cells. This is also the case in research andrology, where very little attention has been given to immature germ cells in the semen apart from some rare exceptions, such as the attempts to study meiosis. Here we report on the use of a discontinuous Percoll gradient method modified to enable the best separation possible of immature germ cells from the other cells found in the ejaculate, in order to obtain a cellular suspension free of spermatozoa. Our technique (intra-assay variation in duplicates < 10%) demonstrated a high immature germ cell concentration in gradient fractions with 30% to 45% Percoll with a small contamination (1.5-6%) of leukocytes, confirmed by May-Grünwald-Giemsa staining, immunofluorescence and cytofluorimetry. The concentrations of immature germ cells ranged from zero in obstructive azoospermia to 2.0 x 10(6)/ml in oligozoospermia and genital tract infection. The purified immature germ cell suspensions obtained can be useful for diagnostic and research purposes.

Cell Separation↗
PubMed1999

Nuclear chromatin variations in human spermatozoa undergoing swim-up and cryopreservation evaluated by the flow cytometric sperm chromatin structure assay.

The sperm chromatin structure assay (SCSA) is a flow cytometric (FCM) technique which exploits the metachromatic properties of Acridine Orange to monitor the susceptibility of sperm chromatin DNA to in-situ acid denaturation. SCSA was used to study the chromatin structure variations of human spermatozoa in semen, both before and after swim-up and after cryopreservation. Semen samples were provided by 19 healthy normozoospermic subjects attending pre-marriage checks. Each sample was divided into three aliquots: the first aliquot was evaluated without further treatment, the second underwent swim-up, and the third was stored according to standard cryopreservation techniques in liquid nitrogen at -196 degrees C. Samples were also analysed by light and fluorescence microscopy (after Acridine Orange staining to evaluate the number of green fluorescent sperm heads), and by computer-assisted semen analysis. The results showed that post-rise spermatozoa represent a subpopulation characterized by a general improvement of the morphological (reduction of the percentage of abnormal forms and heads, increase of the green head sperm percentage) and kinetic parameters. This subpopulation also exhibited improved chromatin structure properties, confirming that these cells have the best structural and functional characteristics, indicative of optimal fertilizing ability. On the other hand, overall sperm quality deteriorates after cryopreservation. When thawed spermatozoa underwent an additional swim-up round, a general improvement of nuclear maturity was seen in the post-rise spermatozoa.

Adult↗
PubMed1999

Effect of 1-year treatment with interferon-beta1b on thyroid function and autoimmunity in patients with multiple sclerosis.

OBJECTIVE: Interferon-beta (IFN-beta) is a widely used therapy for multiple sclerosis (MS), a demyelinating disease of the central nervous system. This study has evaluated the effect on thyroid function and autoimmunity of a 1-year treatment with IFN-beta1b in patients with MS. PATIENTS: We studied 31 patients (age 34+/-7 years, 21 women) with relapsing-remitting MS during IFN-beta1b treatment of 1 year duration. Systematic thyroid assessment and measurements of serum interleukin-6 (IL-6) levels were performed at baseline and every 3 months during treatment. RESULTS: Sixteen percent of the patients had autoimmune thyroiditis before IFN-beta1b, all positive for anti-peroxidase antibodies. The overall incidence of thyroid dysfunction was 33% over 1 year (10% hyperthyroidism, 23% hypothyroidism). Thyroid autoimmunity developed in 5/26 patients (19%), in one case without dysfunction. In addition to autoantibody positivity at baseline, female gender and the presence of an ultrasound thyroid pattern suggestive of thyroiditis were identified by multiple logistic regression as additional risk predictors for the development of thyroid dysfunction. During IFN-beta1b treatment, serum IL-6 levels rose in a consistent biphasic pattern; there was, however, no difference between patients with or without incident thyroid abnormalities. CONCLUSIONS: We conclude that IFN-beta1b therapy can induce multiple alterations in thyroid function, some of which are unrelated to thyroid autoimmunity. IL-6 measurement is not useful to identify patients prone to develop thyroid abnormalities. Though thyroid dysfunction is generally subclinical and often transient, systematic thyroid assessment should be performed during IFN-beta1b treatment.

Adjuvants, Immunologic↗
PubMed1999

[Mallory-Weiss syndrome. Outcome of 160 cases].

The Mallory-Weiss (M-W) syndrome is responsible for about 7.5% of all bleedings of oesophageal origin. Emergency endoscopic treatment allows to obtain a rapid diagnosis as well as an effective treatment. Personal experience on 160 cases of M-W tears (14.2% of all oesophageal bleeding) is reported. The tears were classified in three groups: IA and IB (30 cases); IIA and IIB (48 cases); IIC and III (82 cases). In the first two groups a complete haemostasis was obtained in 73 out of 78 cases (93.6%) with a single session and in 5/78 cases with two sessions of sclerotherapy. The third group was treated with medical therapy. There was no procedure related mortality. An analysis of etiologic factors, anatomic conditions and pathogenetic correlations has highlighted the role of portal hypertension in cirrhotic patients in favouring the bleeding in some of these patients and the role of hiatal hernia and cardial incontinence in determining the site of the lesions.

Adolescent↗
PubMed1999

Salivary gland-specific gene expression in the malaria vector Anopheles gambiae.

Molecular studies on the tissue-specific gene expression in the salivary glands of Anopheles gambiae may provide useful tools for the development of new strategies for the control of the most efficient malaria vector in the sub-Saharan Africa. We summarize here the results of a recent investigation focused on the isolation of secreted factors and putative receptors from the salivary glands of An. gambiae. Using the Signal Sequence Trap technique we have identified the first cDNAs specifically expressed in the An. gambiae salivary glands. Among these, four are exclusively expressed in female glands and encode factors presumably involved in blood-feeding, whereas two other cDNAs seem to be expressed both in male and in female glands and are likely implicated in sugar-feeding. Homologues of genes previously identified in the yellow fever mosquito Aedes aegypti, like the apyrase and D7, as well as novel salivary gland-specific cDNAs, were identified. The isolation and characterization of promoter sequences from the corresponding genes may prove useful for the expression of anti parasitic agents in the salivary glands of transgenic mosquitoes.

Amino Acid Sequence↗
PubMed1998

Endoscopic clipping of anastomotic leakages in esophagogastric surgery.

BACKGROUND AND STUDY AIMS: Anastomotic leakage is a severe complication in gastric surgery and it is associated with a high rate of mortality. Conservative treatment sometimes is not sufficient to stem the leakages and, even when it is sufficient, it takes a long time. The present study describes the first experience in the treatment of anastomotic leakages with endoscopic clipping. PATIENTS AND METHODS: From May 1995 to December 1996, seven patients with postoperative anastomotic leakages after gastric surgery were prospectively treated in our Endoscopy Service. Metallic endoclips (MD 850, Olympus Corp., Tokyo, Japan) with prongs 12 mm long and 6 mm wide were applied, controlling the closure of the leakage by endoscopy, using radiographs to confirm the closure 24 hours later. RESULTS: Complete closure of the leakage was obtained in all seven cases. A single session of endoscopic clipping was needed for five patients while two other required, respectively, two and three sessions. The median time of leakage closure after endoscopic clipping was 2.3 days (range 1-5 days). The clips spontaneously dislodged within 1 month in five patients and within the second month in the other two patients. CONCLUSION: Endoscopic treatment of anastomotic leakages by metallic clips represents a safe and easily repeated method and, compared to conservative treatment, it seems to offer several time and cost advantages. Further studies involving a larger number of patients are needed to verify this finding.

Adenocarcinoma↗
PubMed1998

Relationships between neuroradiological and clinical features in apparently idiopathic hypopituitarism.

In this study, perinatal history, postnatal auxological and clinical evolution and endocrine features were retrospectively evaluated in 49 children, adolescents and young adults with apparently idiopathic hypopituitarism. They were divided into two groups according to magnetic resonance images: 32 patients with isolated pituitary hypoplasia (group A) and 17 with pituitary stalk interruption syndrome (group B). The aim of the study was to assess whether these neuroradiological pictures are associated with specific endocrine and clinical patterns. No significant difference in terms of gestational age, intrauterine growth and rates of adverse perinatal events was found between the two groups. Clinical signs documenting the existence of pituitary dysfunction in utero or shortly after birth were either slightly (micropenis, cryptorchidism, cholestatic jaundice) or significantly (hypoglycemia) more frequent in patients in group B. Although diagnosis of hypopituitarism was made significantly earlier in patients in group B, height deficiency at diagnosis was similar in both groups. Endocrine investigations revealed a more severe and widespread impairment of pituitary function among those in group B. The main conclusion is that the postnatal clinical course is more severe when growth hormone deficiency is associated with pituitary stalk interruption syndrome than when the pituitary is only reduced in height, probably because of the more severe and widespread impairment of pituitary function in the former cases.

Adolescent↗
PubMed1998

Glucose tolerance, insulin secretion and peripheral sensitivity in thalassaemia major.

Glyco-metabolic status was evaluated in 29 pubertal homozygous thalassaemics aged from 17 to 42 years and in 12 age-matched healthy subjects. Diagnosis of diabetes mellitus was assessed in 4 patients (13.8%), who became diabetic after the age of 18 years. With respect to controls non-diabetic patients exhibited significantly higher fasting plasma glucose levels and more sustained glycemic responses to oral glucose tolerance test, whereas their overall insulin output was significantly lower. Moreover non-diabetic thalassaemic patients showed a clear reduction of both beta-cell function and insulin resistance indices (HOMA model). In conclusion our data show a high prevalence of diabetes but do not support the existence of an insulin resistant status in thalassaemia major, at least in adulthood.

Adolescent↗
PubMed1997

Unilateral cryptorchidism corrected in prepubertal age: evaluation of sperm parameters, hormones, and antisperm antibodies in adult age.

OBJECTIVE: To evaluate whether prepubertal orchidopexy for unilateral cryptorchidism can reduce adult dysspermia. DESIGN: Patient follow-up comparison with control groups. SETTING: Surgical and endocrinologic sections of a children's hospital and a university infertility-care center. PATIENT(S): Seventy-one patients with unilateral cryptorchidism who underwent orchidopexy in prepubertal age (6.4 +/- 2.8 years) were followed up as adults (20.0 +/- 2.8 years). MAIN OUTCOME MEASURE(S): Patients underwent testicular examination and hormonal evaluation, 49 of these had semen analysis and antisperm antibody tests. Semen results were compared with those of two age-matched control groups: a group of 20 healthy, randomly selected subjects and a group of 20 patients operated on in postpubertal age for cryptorchidism. RESULT(S): Unilateral reduced testis size was found in 30.1% of patients, eight patients had a low LH level, eight had a low T level, and none had abnormal FSH values. Antisperm antibodies were found in 1 of 49 cases. Cluster analysis of sperm parameters showed that the mean values of patients were worse than those of the healthy controls but better than those of the subjects operated on in postpubertal age. CONCLUSION(S): This study indicates that prepubertal orchidopexy can given better results than postpubertal correction.

Adult↗
PubMed1997

Migration of metallic clips used during laparoscopic cholecystectomy and formation of gallstones around them: surgical implications from a prospective study.

Two groups of patients, with laparoscopic cholecystectomy (LC) were prospectively studied. All patients had serial plain abdominal X-ray examinations at various intervals after operation, to record the position of clips placed during LC. Seventy-one patients had less cystic duct (CD) dissection and > or =4 clips placed during the procedure. One hundred and fifteen patients had a larger CD dissection and only 4 clips placed (2 on the cystic artery and 2 on the CD, without additional clips on smaller vessels). In the former group, 7 patients had clip migration within 1 month and 11 within 1 year vs 1 either at 1 month or 1 year in the latter group (p = 0.01 and <0.001, respectively). During the follow-up, a 72-year-old man belonging to the former group had a recurrent common duct brown pigment stone containing a metallic clip 26 months after operation. He was treated successfully by endoscopic sphincterotomy. Factors predisposing to clip migration were short cystic stump, inadvertent clip dislodgment or incorrect placement, cystic duct ischemic necrosis, and local suppurative complications. Data from 29 patients with GS formed around suture material or phytobezoars observed during a prospective study and from the physicochemical and structural analysis of a cumulative series of 64 GS containing foreign bodies are also presented and discussed. It is suggested that metallic clips can migrate from their initial sites at various intervals within the peritoneal cavity or into the common duct and serve as a nidus for GS formation. Metallic clip migration in most cases is due to technical factors and can usually be prevented. However, it is not possible to prevent either clip migration or GS formation in every case, since even well-placed clips can migrate due to suppurative complications or local ischemic damage, and, once that penetration within the bile tract has occurred, GS are usually going to form, irrespective of the nature and the shape of the foreign body.

Adolescent↗
PubMed1997

The in-vitro effects of nicotine and cotinine on sperm motility.

Swim-up spermatozoa from the seminal samples of non-smokers, usually not exposed to passive smoking, were treated in vitro with nicotine (NIC) and cotinine (COT) at the average levels found in smokers' seminal plasma and at levels 500 times higher than this average. This was done to evaluate the action of these drugs on sperm motility. Each sample was allowed to swim up in Tyrode's solution with or without the drug; the study was carried out at time 0 and +1, +2, +4, +8 and +24 h of incubation, using a light microscope and a CASA system (experiment 1). In addition, the direct action of smoke on spermatozoa was studied using aspirated cigarette smoke (experiment 2). Kinetic parameters were then measured at 30 min, 45 min and 60 min starting from the last smoke injection. The first experiment showed that NIC and COT at average levels did not produce statistically significant variations of the kinetic parameters studied up to 24 h. However, the much higher concentration significantly altered all the kinetic variables in relation to the time of incubation. The second experiment with smoke in toto demonstrated a sharp reduction in all the sperm kinetic parameters. This reduction was seen after 30 min exposure to smoke and increased progressively until almost complete immotility at 1 h of exposure. These results suggest that NIC and COT are not responsible for the harmful effects of cigarette smoke on sperm kinetic parameters reported in the literature.

Adult↗
PubMed1997

Antisperm antibody detection: 1. Methods and standard protocol.

PROBLEM: Today, antisperm antibody (ASA) detection is one of the most important steps in the evaluation of male infertility. This practice is generally accepted even though there is still some disagreement about the meaning of antisperm immunity and a good deal of controversy about the test regarded as the most suitable for the detection of antibodies directed against sperm antigens. International workshops have tried to standardize universally accepted protocols. A panel of three or four methods is generally advised to provide a correct and complete screening of patients with antisperm immunity. METHOD OF STUDY: This paper reports on the results of a serum exchange workshop for the standardization of the ASA detection in the sera carried out under the auspices of the Italian Society of Endocrinology, which was used as reference laboratory. A careful description of the most widely used methods is reported and proposed as a standard protocol also on the basis of the results of the correlation studies carried out by our group is also reported. CONCLUSIONS: If the proposed methods and procedures will be accepted by the members of the Alps-Adria Society for Immunology of Reproduction, a Study Group for Sperm Antibody Testing, could start its activity having the goal of reaching a consensus on methodology and carrying out a European serum exchange workshop.

Agglutination Tests↗
PubMed1997

Antisperm antibody detection: 2. Clinical, biological, and statistical correlation between methods.

PROBLEM: In clinical andrology, the detection of antisperm antibodies (ASA) is regarded as one of the most important steps in the study of male infertility. This practice is generally accepted even though there is still some disagreement about the true meaning of antisperm immunity, and there remains a good deal of controversy about the test regarded as the most suitable for the detection of antibodies directed against sperm antigens. International Workshops have tried to standardize universally accepted protocols. A panel of three or four methods is generally advised to provide a correct and complete screening of patients with antisperm immunity. The aim of the present paper is to report our studies on the correlation between direct methods (IBT, MAR test) and indirect methods (gelatin agglutination test [GAT], and tray agglutination test [TAT]) and to establish whether biological models can explain the antibody test results. An attempt was also made to establish a "predictive threshold" to explain even apparently discordant direct and indirect results.

Agglutination Tests↗
PubMed1996

Computation of brain-blood partitioning of organic solutes via free energy calculations.

The ratio of brain-blood partitioning, log(Cbrain/Cblood) (log BB), of a series of compounds that range from simple solutes to histamine H2 antagonists was correlated with computed solvation free energy in water (delta G degree W). The free energies were computed with the AMSOL 5.0 program using the AM1-SM2.1 solvation model. From a set of 55 compounds, a function was developed in which log BB was related to the free energy of solvation as follows: log BB = 0.054 delta G degree W + 0.43 (r = 0.82 and standard error = 0.41). This correlation provided successful prediction of brain-blood partitioning for compounds outside the training dataset. Furthermore, for a set of 10 drugs, delta G degree W correlated well with literature data for the permeability of endothelial cell monolayers from bovine brain microvessels. In neuroscience drug discovery, the use of computed solvation free energies to predict brain penetration provides a facile method for prioritizing synthetic targets.

Animals↗