Assessment of efficacy and safety of pandemic A/H1N1/2009 influenza vaccine in a group of health care workers.

INTRODUCTION: The development in an extremely short time of an efficacious and safe vaccine against the pandemi A/H1N1 virus was a challenge that involved the entire scientific community. AIMS: To assess the immunological and clinical efficacy of the new H1N1v monovalent influenza vaccine (Focetria Novartis Vaccines, Siena, Italy) in a group of health care workers (HCWs). METHODS: A total of 148 volunteer HCWs were enrolled between Mid-Novembre 2009 and December 2009. After measuring antibody titers, a single intramuscular dose of 7.5 microg of Focetria monovalent vaccine against A/H1N1/2009 influenza virus with MF59C.1 adjuvant was administered. RESULTS: Antibody titers (median value) before and after a single dose of vaccine, measured by means of standard beam-agglutination inhibition test (HAI), increased from 32 to 256 (p < 0.001). After vaccination, 79.7% of the subjects showed antibody seroconversion, and in 97.3% seroprotection was achieved. The ratio between the geometric means of antibody titers (GMTR) was 6.69. For the 3 subjects who reported symptoms of ILI (Influenza-like illness), a regular nasal-pharyngeal swab sample was taken to identify the virus type by RT-PCR, the laboratory results of tests performed on these samples were negative for pandemic A/H1N1/2009 virus. During the entire follow-up period of 6 months no severe adverse events occurred. CONCLUSIONS: The vaccine against pandemic A/H1N1/2009 virus provided protection against the virus and not only contributed to a significant immunization (according to EMEA criteria), but kept all 148 subjects under study free from A/H1N1/2009 influenza illness.

Ultrasonographic evaluation of gallbladder volume and contractility in diabetic patients of different ages.

Gallbladder volume and contractility were measured, by means of real-time ultrasonography, in 48 insulin treated diabetic patients free from autonomic neuropathy, and in 91 healthy control subjects. All controls and diabetic patients were on a isocaloric and balanced diet. Gallbladder measurements were taken after an overnight fast and again 60-75 minutes after each meal. Gallbladder volume was at all times significantly greater in diabetic patients than in controls, while gallbladder contractility was similar. In diabetic patients, but not in controls, gallbladder volume was greater in the elderly than in adults, with no relationship between gallbladder volume and duration of diabetes. It is concluded that enlargement of the gallbladder might be a risk factor for gallstones in diabetic patients.

Effect of phototherapy on plasma levels of GH, LH and FSH in the newborn.

Plasma levels of GH, LH and FSH were measured in 74 three-day-old newborn infants with hyperbilirubinemia before and after exposure to continuous phototherapy (PhT) for 48 h. The results obtained were compared with data observed over the same period of time in 46 newborn infants belonging to the control group having homogeneous characteristics as far as form of delivery (spontaneous), gestation age, chronological age, sex, birth weight and basal blood glucose were concerned, except hyperbilirubinemia and necessity of PhT. Hyperbilirubinemic female newborn showed higher plasma GH concentrations in comparison with hyperbilirubinemic males and with controls. Forty-eight of continuous PhT significantly reduced GH levels which, however, appeared not to be substantially different from those of normal controls of the same age. Moreover, PhT determined a slight trend to increase in FSH of females, and did not modify the physiological decline of LH in both sexes during the first five days of life. The reduction of GH following PhT from abnormal to physiological concentrations may be due to the direct effect of light and/or to continuous light-related disorders of sleep. In conclusion, 48 h of continuous exposure to light (PhT) do not impair the newborn's pituitary functions here studied.

Inhibition of puerperal lactation by metergoline: interactions with methylergobasine maleate.

Metergoline, a prolactin (PRL) lowering drug, is used in the puerperal period to inhibit lactation. Methylergobasine maleate (MEM), widely employed in the puerperium to promote uterine contractions, has also been reported to decrease PRL release and to reduce lactation. To evaluate the possible interactions of the two drugs, groups of 6-11 puerperae each received no treatment, metergoline alone (8 or 12 mg/day for 5 days), MEM alone (0.2 mg i.v. at delivery followed by 0.5 mg/day p.o. for 5 days) and metergoline plus MEM. Metergoline fully prevented lactation and significantly reduced PRL release, the higher dose inducing effects faster. MEM was without effect on PRL release and lactation, and did not modify the effect of metergoline.

Metergoline versus bromocriptine in the prevention of puerperal lactation. A double-blind clinical trial.

In a double blind study of the prevention of puerperal lactation, the clinical efficacy of two antiprolactin drugs was compared: metergoline 4 mg tid and bromocriptine 2.5 mg bid were both given for 7 days. An additional 7 days of treatment was administered to 16 patients in whom mammary activity was still present or appeared in the following 3 days. The first 7 day period of treatment was effective in 16/20 women receiving metergoline and in 7/20 on bromocriptine (p less than 0.02); the second period of treatment was effective in all remaining patients. These data indicate that metergoline acts rapidly to arrest puerperal lactation, possibly by a mechanism different from that of bromocriptine.

The effect of histamine and H1 and H2 receptors on prolactin and luteinizing hormone release in humans: sex differences and the role of stress.

The present experiments were performed to investigate the possible role of histamine and its receptors, H1 and H2, in the control of PRL and LH release in normal adult humans of both sexes. Histamine infusion (200 microgram, iv, in 15 min) induced PRL and LH release in men; in women, histamine inhibited LH release without affecting PRL release. Two H1 antagonists, dexchlorpheniramine (10 mg, iv) and promethazine (50 mg, im), reduced PRL release in both sexes, stimulated LH release in men, and inhibited LH release in women. Cimetidine, an H2 antagonist (400 mg, iv), elicited PRL release in both sexes, more consistently in females than in males, and was without effect on LH release in either sex. These data suggest that in humans, the effect of histamine on PRL release is linked to H1 and H2 receptors, which respectively stimulate and inhibit PRL release independently of sex. The effect of histamine on LH release appears to depend on sex and to be mediated only by H1 receptors. To rule out the possibility that the effects of histamine are merely due to a nonspecific stress reaction, we have evaluated PRL and LH release in otherwise normal men and women undergoing surgery for gallstones. Surgery was accompanied by PRL release in both sexes, more evident in women, and by LH release only in men. These results indicate that the effect of histamine on PRL and LH release in humans is linked to sex and H1 and H2 receptors and is not due to stress; further studies are required to clarify the possible mechanism and site of action of histamine in modifying PRL and LH release in humans.

[The effect of methergoline and of a synthetic estrogen on plasmatic prolactin levels and on postpartum lactation]. / Effetto della metergolina e di un estrogeno di sintesi sui livelli di prolattina plasmatica e sulla montata lattea nel post-partum.

PIP: 30 women who, for various reasons, did not wish to breastfeed were treated with 12 mg of methergoline a day, for 5 days, while a second group of women were treated, for the same purpose, with 450 mg of resorcilic acid lactone for 5 days. In the first group not only lactation was totally suppressed, but plasma prolactin levels were significantly reduced. In the second group lactation was inhibited, but prolactin levels remained the same.^ieng

Interaction of dopaminergic and antiserotoninergic drugs in the control of prolactin and LH release in normal women.

Prolactin (Prl) release, both in the experimental animal and in man, is stimulated by serotonin (5HT) and inhibited by dopamine (DA). Data also suggest that LH release in the animal is stimulated by norepinephrine and inhibited by DA. The role of 5HT in the control of LH release is less clear. It would appear to stimulate episodic LH release and to inhibit the LH surge at the pro-oestrus in animals, but the effect of 5HT on LH release has not yet been evaluated in man. In the present paper we have studied the effect of various DA-ergic drugs (DA, iv l-dopa, po l-dopa and bromoergocriptine) and of two anti-5HT drugs, metergoline and methysergide, on Prl and LH release in normal women. DA-ergic drugs lowered plasma Prl and LH levels; anti-5HT drugs, at doses able to lower Prl levels, did not affect basal LH release nor the inhibiting effect of iv l-dopa on LH release. These data indicate that DA inhibits both LH and Prl release in normal women, and that 5HT stimulates Prl release but is not involved in the regulation of LH secretion. The fact that, at variance to all the DA-ergic drugs used, the two anti-5HT drugs did not vary LH release, suggests that metergoline and methysergide are devoid of DA-ergic activity in man, at least at the doses able to inhibit Prl release.

Study on the reproducibility of human prolactin response to sulpiride, benserazide, insulin hypoglycaemia and arginine infusion.

In order to evaluate the spontaneous variability of prolactin (PRL) release in response to various stimuli applied repeatedly on different occasions, groups of 5 to 12 subjects each underwent consecutive identical tests with one of the following stimuli applied at 3-6 days' intervals: sulpiride (100 mg im), benserazide (50 mg po), insulin hypoglycaemia (0.1 U/kg b. w. iv) and arginine infusion (25 g iv in 30 min). When repeated in the same subjects, arginine and benserazide yielded superimposable results. In contrast to this, insulin hypoglycaemia yielded significantly lower PRL release, while the PRL response to the second sulpiride test was significantly higher than to the first one. When an interval of 10 days was left between two consecutive sulpiride tests, an identical PRL release was observed. These results indicate that arginine and benserazide are reproducible tests for PRL secretion and it is possible that the decreasing effect of insulin hypoglycaemia on PRL release is due to the stressful effect of the stimulus. Finally, sulpiride probably enhances both PRL release and synthesis thus making greater amounts of PRL available to a subsequent stimulus. Since some of the above stimuli are usual tools for the study of the neuroendocrine control of PRL secretion, our findings suggest that caution appears necessary in attributing to any (neuroactive) drug an effect which might be merely due to a lack of reproducibility of the stimulus employed.