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Biomedical subjects

A Ferrara

Publications and source records attributed to A Ferrara.

At least 73 records · Page 4Linked to original sources
PubMed1996

Sporadic fundic gland polyps: an immunohistochemical study of their antigenic profile.

Fundic Gland Polyps (FGPs) are small sessile (2-5 mm), usually multiple polyps arising in the gastric, acid-secreting mucosa of disputed histogenesis. They have been described in a sporadic form, prevalently in middle aged females, or associated with familial adenomatosis coli-Gardner's syndrome. We performed an immunohistochemical study on 24 sporadic FGPs, using monoclonal antibodies (MAbs) against differentiation markers, class II MHC antigens (HLA-DR), oncofetal and proliferation antigens, aimed to characterize the antigenic profile of the polyps. A preliminary cytogenetic study on five polyps was also done, using an in situ culture method after collagenase treatment. Cytokeratins 8-18 (CAM 5.2 MAb) and 20 (IT-Ks 20.8 MAb), Epithelial Membrane Antigen (EMA) and Chromogranin A were normally expressed by FGPs. FGPs did not express HLA II DR. FGPs did not react with an anti-CEA MAb (F6), but they were frequently positive (22/24, 91.6%) with B72.3 MAb (reacting with the cancer-associated mucin epitope sialyl-Tn). The PC10 MAb (against PCNA or cyclin) showed enhanced expression in the deep glandular-cystic compartment of FGPs; the PCNA index of FGPs was significantly higher than in normal fundic mucosa. The cytogenetic study on the 5 cases analysed, revealed a normal karyotype. We have demonstrated that FGPs express in the paranuclear zone the sialyl-Tn epitope, a side-chain sugar normally masqued in adult gastric mucins, thus revealing an alteration in mucin synthesis; FGPs' higher proliferation index as compared with normal fundic mucosa supports the hypothesis of their hyperproliferative nature.

Antigens, Neoplasm↗
PubMed1996

Stimulus range effects in temporal bisection by humans.

Two experiments with human subjects, using short-duration tones as stimuli to be judged, investigated the effect of the range of the stimulus set on temporal bisection performance. In Experiment 1, six groups of subjects were tested on a temporal bisection task, where each stimulus had to be classified as "short" or "long". For three groups, the difference between the longest (L) and shortest (S) durations in the to-be-bisected stimulus set was kept constant at 400 msec, and the L/S ratio was varied over values of 5:1 and 2:1. For three other groups, the L/S ratio was kept constant at 4:1 but the L-S difference varied from 300 to 600 msec. The bisection point (the stimulus value resulting in 50% "long" responses) was located closer to the arithmetic mean of L and S than the geometric mean for all groups except that for which the L/S ratio was 2:1, in which case geometric mean bisection was found. In Experiment 2, stimuli were spaced between L and S either linearly or logarithmically, and the L/S ratio took values of either 2:1 or 19:1. Geometric mean bisection was found in both cases when the L/S ratio was 2:1, but effects of stimulus spacing were found only when the L/S ratio was 19:1. Overall, the results supported a previous conjecture that the L/S ratio used in a bisection task played a critical role in determining the behaviour obtained. A theoretical model of bisection advanced by Wearden (1991) dealt appropriately with bisection point shifts discussed above but encountered difficulties with stimulus spacing effects.

Adult↗
PubMed1996

Effective peritoneal and fascial closure of abdominal trocar sites utilizing the Endo-Judge.

With the increasing frequency of minimally invasive surgical procedures, we have begun to see descriptions of new and unforseen complications. One such complication is the formation of a ventral hernia through an unclosed or poorly closed fascial defect created by trocar insertion. The necessity to perform fascial closure of trocar insertion sites, particularly those greater than 5 mm, has been established and is routinely practiced by the majority of laparoscopists. Standard suture techniques can be difficult and frustrating, and often involve blind closure of the fascial defect. A number of instruments have been developed to facilitate this fascial closure. We are currently using a self-contained disposable fascial closure device (Endo-JudgeTM--Synergistic Medical Technologies, Inc., Orlando, Florida), which is quick and relatively simple to use. It enables secure fascial closure under direct vision with the pneumoperitoneum intact. Initial results reveal consistent fascial and peritoneal closure and no postoperative hernia formation.

Abdominal Muscles↗
PubMed1996

Dehydroepiandrosterone, dehydroepiandrosterone sulfate, obesity, waist-hip ratio, and noninsulin-dependent diabetes in postmenopausal women: the Rancho Bernardo Study.

Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) levels were determined in morning specimens from 659 fasting postmenopausal women who were not using estrogen therapy or antidiabetic medication. All women had concurrent oral glucose tolerance tests and measurements of body mass index (BMI) and waist-hip ratio (WHR). DHEA levels were weakly and inversely associated with BMI but not with WHR or glucose tolerance status. DHEAS levels were not associated with BMI but were positively associated with WHR, diabetes, and impaired glucose tolerance. In analyses adjusted for or stratified by WHR, the DHEAS association with abnormal carbohydrate tolerance was reduced but still independent of fat distribution. Because this was a cross-sectional study, it was not possible to determine whether DHEAS levels were raised by central obesity or vice versa. At a minimum, these data strongly suggest that the positive association of DHEAS with both central obesity and abnormal glucose tolerance does not support the thesis that DHEAS protect against diabetes or obesity in older women as had been suggested by animal studies.

Aged↗
PubMed1996

Thyroxine effect on intestinal Cl-/HCO3- exchange in hypo- and hyperthyroid rats.

Changes in transepithelial water and electrolyte transport as causative or contributing factors of the diarrhoea and constipation found associated with changes in thyroid physiology were studied. Albino Wistar rats were pharmacologically made either hypothyroid or hyperthyroid. After sacrifice, the small intestine was mounted in Ussing chambers in order to measure in vitro ion net fluxes under short-circuit conditions. Hypothyroid animals showed an increase in intestinal transit time, Cl- absorption (mainly due to an increment in its mucosal to serosal component) and residual ion flux (which is believed to represent HCO3- secretion) when compared with euthyroid animals. The hyperthyroid animals showed a decrease in Cl- mucosal to serosal transport. Furthermore, a significant correlation was found between serum L-thyroxine (T4) levels and both net Cl- transport (r = -0.74, P < 0.00001) and residual ion flux (r = -0.55, P < 0.005). These results indicate that the effect of T4 is firstly to inhibit Cl-/HCO3- anion exchange thereby influencing transepithelial flux transport and secondly to affect intestinal motility. Such inhibition was not found when T4 was acutely added to rat ileum, suggesting that the effect on electrolyte transport probably requires protein synthesis. In conclusion, the phenomenon observed in vitro could explain the clinical manifestations of constipation and diarrhoea in hypo- and hyper-thyroidism respectively.

Animals↗
PubMed1995

Cholecystokinin effect on human lymphocyte ionized calcium and mitogenesis.

Cholecystokinin (CCK) is a peptide present in large amounts in gut, brain, and neurons innervating lymphatic tissues. Plasma CCK levels increase in enterally alimented patients. Enteral alimentation is also associated with enhanced immune function. The effects of CCK and a CCK antagonist were studied on human peripheral blood mononuclear cells (H-PBMC), lymphocyte intracellular ionized calcium ([Ca2+]i), and lymphocyte mitogenesis. CCK receptors transduce their signal via the release of [Ca2+]i. CCK octapeptide caused a specific increase in [Ca2+]i measured by Fura-2 fluorometry in H-PBMC and human T helper lymphocytes. Neither gastrin-17 nor pentagastrin produced a signal. While the highly specific CCK antagonist MK329 blocked the CCK [Ca2+]i signal, it had no effect on the PHA-mediated signal. At high dosages (10(-7)-10(-8) M), CCK was a comitogen with "complete" lymphocyte mitogens such as anti-CD3 monoclonal antibody (mAb) or low-dose PHA, but not for "partial" mitogens such as phorbol esters. CCK comitogenic effect occurred even in the presence of cyclosporine. CCK radioimmunoassay demonstrated that H-PBMC contained CCK and that anti-CD3 mAb- or PHA-mediated H-PBMC mitogenesis caused release of CCK. MK329 blocked PHA and anti-CD3 mAb mitogenesis and CCK comitogenic effects. We conclude that CCK octapeptide may be a coregulator of lymphocyte Ca2+ activation signals. The immunologically beneficial effect of enteral nutrition may, in part, be mediated by increased levels of CCK.

Benzodiazepinones↗
PubMed1995

Twenty-year review of the surgical management of perianal Crohn's disease.

PURPOSE: A retrospective analysis of 48 patients treated over a 20-year period (March 1973-April 1993) was undertaken to assess the results of our practice of early surgical intervention in suppurative complications of perianal Crohn's disease. METHODS: All patients were either seen in the office within the last six months or contacted by phone. RESULTS: The average age of our patients was 30 years at initial diagnosis. Thirty-four patients (71 percent) initially presented with intestinal disease and four (8 percent) with only perianal disease. Thirteen patients (27 percent) initially presented with simultaneous intestinal and perianal disease. The various fistulas at initial presentation included 8 intersphincteric (17 percent), 14 transphincteric (29 percent), 11 complex or multiple (23 percent), 5 rectovaginal (10 percent), and 2 unclassified, for a total of 40 patients. Eight patients (17 percent) presented with only an abscess. Eighty five percent of our patients healed after their first procedure, with an average time to heal of 2.8 months. Thirteen (27 percent) patients had recurrences after initial healing of their wounds. The mean time to recurrence after healing was 5.25 years. Fifty-four percent of our recurrences (7 patients) were treated by incision and drainage of an abscess only. Seven of 13 recurrences healed after the second procedure (54 percent), and 5 of 6 healed after a third procedure (83 percent). Only seven (14 percent) of our patients underwent a proctocolectomy during the study period, through September, 1993. Our overall probability of avoiding proctectomy and healing perineal wounds of 86 percent is consistent with published literature. CONCLUSIONS: Early aggressive surgical management of suppurative complications of perianal Crohn's disease before complex management problems ensue results in a high incidence of healing and a low risk of subsequent proctectomy.

Abscess↗
PubMed1995

Lipoprotein(a) concentrations in non-insulin-dependent diabetes mellitus and borderline hyperglycemia: a population-based study.

The objective of the study was to compare lipoprotein(a) [Lp(a)] concentrations in population-based samples of individuals with non-insulin-dependent diabetes mellitus (NIDDM), borderline hyperglycemia, and normoglycemia. From 2,740 male Italian Telephone Company employees aged 40 to 59 years participating in a health screening, we selected all those with NIDDM (n = 100) plus a random sample of 950 nondiabetic individuals. Diabetes was defined as fasting plasma glucose (FPG) of at least 140 mg/dL or current use of hypoglycemic drugs. Among nondiabetic individuals, 854 were defined as normoglycemic (FPG < 115 mg/dL) and 95 were defined as borderline hyperglycemic (115 < FPG < 140 mg/dL). Lp(a) level was measured on frozen plasma by enzyme-linked immunosorbent assay. Lp(a) concentrations were similar in people with NIDDM, borderline hyperglycemia, and normoglycemia: 11.2 +/- 14, 14.1 +/- 20, and 13.9 +/- 18 mg/dL, respectively (F = 1.03). Accordingly, the proportion of subjects with Lp(a) levels of at least 30 mg/dL was comparable in the three groups (12%, 15%, and 14%; chi 2 = 3.95, P = .41). Results were not confounded by differences in age, body mass index (BMI), waist to hip ratio, plasma lipids, alcohol consumption, physical activity, and use of drugs. Furthermore, within the diabetic group Lp(a) levels were not significantly different for those on diet only versus those on oral agents (10.8 +/- 14.1 v 11.7 +/- 14.7, P = .7) or for people with FPG of at least 180 as compared with people with FPG less than 180 mg/dL (9.9 +/- 12.8 v 11.5 +/- 14.8, P = .5).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Dizziness and vertigo in a department of emergency medicine.

Dizziness is a common and vexing diagnostic problem in emergency departments. The term is rather undefinite and often misused, but can in practice be classified into four categories: fainting, disequilibrium, vertigo and miscellaneous syndromes. Vertigo is the most common category of dizziness. Classification of vertigo can be based either on chronological criteria (acute, recurrent or chronic vertigo) or on topographical criteria (peripheral or central vertigo). Physicians working in emergency departments must be able to rapidly identify patients with potentially serious forms of vertigo, which could cause death or disability, and patients with mild conditions, that can be effectively treated. Previous studies and the experience of the authors have shown that reliable diagnostic hypotheses can be generated by taking a proper clinical history (focused on the onset and duration of the disease, the circumstances causing the vertigo and associated otological or neurological symptoms) and performing an accurate physical examination (evaluation of neurological defects and spontaneous or provoked nystagmus), supplemented by few laboratory tests and diagnostic procedures. Therapy of vertigo in emergency settings is mainly symptomatic and based on sedation and use of vestibulosuppressant drugs (antihistamines, phenothiazines).

Algorithms↗
PubMed1995

Sex differences in insulin levels in older adults and the effect of body size, estrogen replacement therapy, and glucose tolerance status. The Rancho Bernardo Study, 1984-1987.

OBJECTIVE--To determine if insulin levels vary with sex, independent of estrogen replacement therapy (ERT), differences in body mass index (BMI), waist-to-hip ratio (WHR), and glycemia. RESEARCH DESIGN AND METHODS--In a population-based study of older adults, insulin levels were measured before and after a standardized oral glucose tolerance test in 673 men and 849 women, all free of known diabetes. RESULTS--Age-adjusted fasting insulin levels were highest in men, intermediate in women not taking estrogen, and lowest in estrogen-treated women (P < 0.01). Differences between men and women not taking estrogen disappeared after adjusting for age and BMI, but not glycemia; estrogen-treated women had significantly lower fasting insulin levels than did men (P < 0.01) and women not taking estrogen (P < 0.01). The association of estrogen use with lower fasting insulin levels persisted after adjusting for age and WHR (P < 0.001) and was stronger among women with abnormal glucose tolerance. Age-adjusted postchallenge insulin levels were higher in women than in men (P < 0.01). The sex difference persisted after adjusting for age and BMI or glycemia. Postchallenge insulin levels did not vary by ERT. CONCLUSIONS--Men have higher fasting insulin levels than do women, whether or not the women are using ERT. Differences between men and untreated women are explained by differences in BMI, but estrogen users have lower fasting insulin levels independent of BMI. Postchallenge insulin levels are higher in women than men and are independent of ERT, BMI, and glycemia. Clinical trials in women are needed to determine whether ERT can improve insulin and glucose metabolism.

Aged↗
PubMed1995

Stimulus spacing effects in temporal bisection by humans.

Two experiments studied the bisection of sets of stimulus durations (ranging from 200 to 800 msec, or 100 to 900 msec) by normal adults. In Experiment 1, two bisection techniques were used: a "similarity" method, where subjects had to classify each duration in terms of its similarity to the shortest and longest members of the set (which were explicitly identified as Short and Long standards), or a "partition" method, where subjects simply classified each duration as Short or Long, without explicit standards. For different groups, the durations within each set were spaced either linearly or logarithmically between the longest and shortest members. The two bisection methods produced similar results, but psychometric functions (proportion of Long judgements versus stimulus length) were shifted to the left in the logarithmic conditions relative to the linear ones--that is, some shorter durations were classified as Long more frequently in logarithmic conditions. Experiment 2 used arithmetic, but unequal, stimulus spacings between the shortest and longest set members, and the partition method. Sets containing more shorter than longer durations had psychometric functions shifted to the left relative to sets with more longer than shorter durations. The data suggest that judgement of some time value, t, depends on the context in which t appears, not only on its value relative to the longest and shortest set members (as most current theories of bisection propose). A model assuming that judgements of t are based on the relation between t and the arithmetic mean of all the durations in the set fitted data reasonably well in most conditions. This model, furthermore, incorporated decision rules used to account for human performance on temporal generalization tasks, thus promoting theoretical integration of the two sorts of experiments.

Computers↗
PubMed1995

[Can the recurrence of nasal polyposis be prevented? A new therapeutic approach].

Nowadays nasal polyposis must be still considered an unsolved problem as the surgical procedures are unable to treat this pathology and the recurrence is very common. For this reason several Authors starting from the pathogenesis and the histological features have chosen a medical point of view at the aim of preventing the natural course of this disease. The present study experimented the effect of the furosemide locally administered in the prevention of polyps relapsing in subjects previously operated on. The Authors pointed out that the furosemide was able to decrease the nasal reactivity to the challenge with ultrasonic nebulized distilled water. Besides this drug locally administered for 3 months (once a day) maintained the nasal mucosa of the patients affected with hyperreactivity in a good functional condition without nasal obstruction. In fact no polyps were found at the objective examinations performed during the three years follow up and the values of acoustic rhinometry measurements were within the normal range. Finally the present research gave the opportunity to hypothesize the role of sodium, potassium and calcium ions transport regulated by drugs or other physiopathological events, in the physiology of the nasal mucosa.

Adolescent↗