In vitro activity of novel in silico-developed antimicrobial peptides against a panel of bacterial pathogens.

Antimicrobial-peptide-based therapies could represent a reliable alternative to overcome antibiotic resistance, as they offer potential advantages such as rapid microbicidal activity and multiple activities against a broad spectrum of bacterial pathogens. Three synthetic antimicrobial peptides (AMPs), AMP72, AMP126, and also AMP2041, designed by using ad hoc screening software developed in house, were synthesized and tested against nine reference strains. The peptides showed a partial ß-sheet structure in 10-mM phosphate buffer. Low cytolytic activity towards both human cell lines (epithelial, endothelial, and fibroblast) and sheep erythrocytes was observed for all peptides. The antimicrobial activity was dose dependent with a minimum bactericidal concentration (MBC) ranging from 0.17 to 10.12 µM (0.4-18.5 µg/ml) for Gram-negative and 0.94 to 20.65 µM (1.72-46.5 µg/ml) for Gram-positive bacteria. Interestingly, in high-salt environment, the antibacterial activity was generally maintained for Gram-negative bacteria. All peptides achieved complete bacterial killing in 20 min or less against Gram-negative bacteria. A linear time-dependent membrane permeabilization was observed for the tested peptides at 12.5 µg/ml. In a medium containing Mg²âº and Ca²âº, the peptide combination with EDTA restores the antimicrobial activity particularly for AMP2041. Moreover, in combination with anti-infective agents (quinolones or aminoglycosides) known to bind divalent cation, AMP126 and AMP2041 showed additive activity in comparison with colistin. Our results suggest the following: (i) there is excellent activity against Gram-negative bacteria, (ii) there is low cytolytic activity, (iii) the presence of a chelating agent restores the antimicrobial activity in a medium containing Mg²âº and Ca²âº, and (iv) the MBC value of the combination AMPs-conventional antibiotics was lower than the MBC of single agents alone.

Pivagabine effects on neuroendocrine responses to experimentally-induced psychological stress in humans.

Neuroendocrinology of chronic stress seems to be characterized by HPA axis hyperactivity and early childhood stressors have been hypothesized to predispose individuals to adult onset depression by means of dysregulation of the HPA axis. Pivagabine (PVG), a hydrophobic 4-aminobutyric acid derivative, has been used experimentally recently in the treatment of different disorders related to stress-maladaptation, because of its possible inhibitory action on corticotrophin releasing factor secretion and HPA axis function. In the present study, 20 healthy male subjects were each exposed twice to the same psychosocial stressor (stroop color-word interference task, public speaking and mental arithmetic in front of an audience) during a first session (day 1) and a second session (day 8). Plasma concentrations of norepinephrine (NE), epinephrine (EPI), adrenocorticotropic hormone (ACTH) and cortisol (CORT), heart rate (HR) and systolic blood pressure (SBP) were measured immediately before the beginning of the tests and at their end, 30 min later, on both experimental days. Utilizing a double blind schedule, the subjects received pivagabine (900 mg, twice a day)(PVG group: nine subjects) or placebo (PBO group: 11 subjects) during the 7 days between the two stress sessions. NE, EPI, ACTH, and CORT levels were significantly elevated after stress exposure on day 1 and day 8 in PBO group subjects. After PVG treatment, on day 8, ACTH, CORT, NE and EPI responses to stress were significantly blunted, together with HR and SBP, in PVG group subjects. These results add to the evidence concerning PVG capacity to inhibit the HPA axis in humans, in response to stressful stimuli, and suggest that the action of PVG may be mediated not only by GABAergic receptors, but also by the suppression of catecholamines response. PVG treatment could modulate HPA hyper-responsiveness to stress in subjects with negative affectivity and depressive traits.

Neuroendocrine correlates of depression in abstinent heroin-dependent subjects.

The functions of the central alpha-adrenergic, serotoninergic and dopaminergic systems were investigated in 28 heroin-dependent subjects 6-8 weeks after detoxification, and in 22 healthy control subjects (group C). Fourteen heroin-dependent subjects with depressive comorbidity (group A), and 14 heroin-dependent subjects without other Axis I and II pathologies (group B) were included among abstinent substance abusers. Norepinephrine (NE) function was evaluated by growth hormone (GH) responses to acute stimulation with clonidine (clon); serotonin (5-HT) function by prolactin (PRL) and cortisol (CORT) responses to acute stimulation with D-fenfluramine (D-fen) and dopamine (DA) function by GH and PRL responses to acute administration of bromocriptine (brom). Central NE activity, as measured by the GH-clon test, seems to be well preserved both in A and B subjects. PRL and CORT responses to D-fen were significantly blunted both in A subjects and in B subjects, in comparison with control subjects (C); the PRL response in A subjects was significantly lower than in B subjects. The DA system of B subjects was found unimpaired; in contrast, a significantly higher GH response to brom in A subjects (depressed) could express D2 post-synaptic receptor hypersensitivity and, therefore, decreased pre-synaptic DA release. In sum, the study of central monoamine function revealed an alteration only of the 5-HT system in detoxified heroin-dependent subjects without psychiatric comorbidity, which might be a trait character of these subjects, possibly involved in the pathogenesis of the disorder. A more significant impairment of 5-HT function and the hypersensitivity of post-synaptic DA receptors in A subjects suggests that specific biological correlates of psychiatric comorbidity may characterize substance abuser subtypes.

Treatment of postmenopausal osteoporosis with continuous daily oral alendronate in comparison with either placebo or intranasal salmon calcitonin.

Alendronate sodium (ALN) is a potent amino bisphosphonate which specifically inhibits osteoclastic bone resorption and has been found to reverse bone loss in several animal models. To determine if daily oral ALN treatment could prevent or reverse bone loss in osteoporotic postmenopausal women, and to compare ALN to intranasal salmon calcitonin (CT), a 2-year, double-masked, randomized, placebo-controlled study was initiated at 9 clinical centers in Italy. Two hundred and eighty six postmenopausal women (age 48-76) with spinal bone mineral density (BMD) > or = 2 SD below adult mean peak, with or without vertebral crush fractures, were randomized to one of four treatment arms: ALN 10 mg daily, ALN 20 mg daily or matching placebo (these groups all double-masked), or CT 100 IU daily (open label) for 2 years. All patients received supplemental calcium (as carbonate) 500 mg daily. Bone mass was measured by dual-energy X-ray absorptiometry of the PA lumbar spine (LS) and proximal femur (femoral neck and trochanter) at 6-month intervals. Subject safety was measured through sequential clinical and laboratory evaluation. A planned 1-year interim analysis of this ongoing study was performed centrally in a manner that maintains the double-mask for all subjects receiving oral study drug. Relative to PBO, ALN at either 10 mg or 20 mg daily increased LS BMD by 4.7% and 6.1%, respectively; each increased femoral neck BMD by 3.1% and increased trochanter BMD by 3.3% and 3.8% respectively. In contrast, CT failed to significantly increase BMD of either the spine, femoral neck or trochanter, either relative to baseline or to PBO.(ABSTRACT TRUNCATED AT 250 WORDS)

[Long-term local tolerability to intranasally administered salmon calcitonin in post-menopausal osteoporosis]. / Tollerabilità locale cronica della Calcitonina di salmone somministrata per via endonasale nell'osteoporosi postmenopausale.

The aim of this study was to acquire further knowledge relative to the local tolerability of synthetic salmon Calcitonin, administered by the intranasal route. The Authors have evaluated several olfactometry parameters in a group of patients treated for twelve months with the drug. The Wright matrix test and the olfacto-respiratory reflex test were performed. An evaluation regarding mucociliary transport time was additionally effected. No interference on the part of the drug was reported regarding the functional parameters of the nasal mucosa. The excellent local tolerability of intranasal salmon Calcitonin, as already indicated by other Authors, was confirmed, even in terms of specific parameters relative to the olfactory functions.

Short-term treatment of Paget's disease of bone with ipriflavone.

Ipriflavone (IP), an isoflavone derivative, seems to prevent the loss of bone mass through the inhibition of bone resorption, mainly inhibiting the recruitment of osteoclasts. We investigated whether a brief course of treatment with IP can reduce biochemical parameters of accelerated bone turnover and bone pain in patients with active Paget's disease of bone. Sixteen patients (9 males and 7 females) with active Paget's disease were randomly allocated to two different crossed-over dose regimens of treatment with IP (600 mg/day vs. 1200 mg/day). Each treatment course lasted 30 days and the wash-out period between the two sequences was 15 days. Serum alkaline phosphatase (Al.Ph.) and urinary hydroxyproline/creatinine excretion (HOP/Cr) were reduced after each sequence. At the end of the 600/1200 mg/day treatment sequence, serum Al.Ph. and HOP/Cr decreased with 32% and 25.6% respectively. At the end of the 1200/600 mg/day treatment sequence, serum Al.Ph. and HOP/Cr decreased with 33% (P < 0.01) and 24.1% (P < 0.05) respectively. Furthermore, a significant decrease in bone pain was observed during the 1200/600 mg/day sequence (P < 0.01). Both treatment schedules were well tolerated and the patients' compliance resulted excellent. Our results indicate that short-term treatment with IP can reduce biochemical parameters of disease activity and bone pain in patients with active Paget's disease of bone.

[Treatment experience with chronic spinal pain in involutional osteoporosis]. / Esperienze di trattamento del dolore cronico del rachide nella osteoporosi involutiva.

The back pain syndrome which accompanies involutional osteoporosis presents a marked heterogeneity. Acute pain may be due to vertebral fractures, whereas chronic pain may eventually accompany established osteoporosis in which clinical and instrumental evidence are present. Back pain is the consequence of the mechanical (internal or external pressure) or chemical stimulation of pain receptors present in bone tissue, along the vessels, in cartilage, joints, disk, ligaments, and also in soft tissue and muscle (with secondary antalgic contracture). The compression of spinal nerves may contribute to the pain as well. An evident alteration of mood is usually present and represents an important element in the syndrome. This phenomenon interferes with the evolution of pain, in particular as regards its intensity. Besides scales for the evaluation of pain and inability, it is possible to check objective data by means of particular algometers (not easy to employ) or by electromyographic measurements of antalgic secondary contracture of spinal muscle. Gait examination (basography) of patients with painful hip prosthesis may provide objective evaluation regarding specific antalgic activity on bone of drugs. Usually the effective drugs for osteoporosis possess antalgic properties as well, with different mechanisms of action. Three drugs with evident activity are taken into consideration: calcitonin, ipriflavon, aminobutane-bisphosphonate (alendronate). Though each of them possesses some particular activity, the main mechanism of action is dependent on their effect on the local microenvironment, particularly at the level of bone tissue (calcium, cytokine and prostaglandin local concentration), on the modulation of osteoclast activity. In particular alendronate (intermittently administered intravenously) exerts the most evident antalgic activity. Subjective chronic back pain relief is accompanied by (secondary) reduction of antalgic contracture at vertebral muscle level. The activity of the substance against the painful hip prosthesis (documented by basographic gait recording) leads us to conclude that the substance really exerts a direct antalgic action at the level of bone tissue.

Avaliaçäo clínica comparativa com placebo de um extrato estabilizado de valeriana / Clinical comparative evaluation of a stabilized valeriana extract and placebo

Quarenta pacientes portadores de sintomas leves de ansiedade e distúrbios de tensäo emocional foram selecionados e randomizados em dois grupos, um tratado com dois comprimidos de 50 mg de valeriana duas vezes ao dia e o outro com placebo, ambos durante 21 dias. A valeriana mostrou-se estatisticamente superior ao placebo. Os resultados clínicos e a ausência de efeitos colaterais confirmam a segurança e a atividade de ambas as drogas no tratamento da tensäo emocional

Intermittent treatment with intravenous 4-amino-1-hydroxybutylidene-1,1-bisphosphonate (AHBuBP) in the therapy of postmenopausal osteoporosis.

Since data on the efficacy of 4-amino-2-hydroxybutylidene-1,1-bisphosphonate (AHBuBP) in the therapy of osteoporosis are not yet available, we have examined in an open, randomized study, the effects of an intravenous intermittent treatment with this drug on the vertebral and radial bone mass in postmenopausal osteoporosis. Forty postmenopausal osteoporotic women were randomly assigned to one of two groups, one treated with AHBuBP (5 mg/day on two consecutive days every 3 months for one year; n = 20), the other with oral calcium (n = 20). The bone mineral density (BMD) of the spine increased significantly in women receiving AHBuBP, whereas it tended to decrease in patients given calcium. The differences in the vertebral BMD changes between groups was highly significant (P less than 0.01). Radial BMD tended to increase in patients treated with AHBuBP, and to decrease in patients receiving calcium. The difference in the linear trends was statistically significant (P less than 0.05). The side effects of AHBuBP (a transient acute phase reaction in 3 out of 20 subjects) were slight and well-tolerated. A good effect of AHBuBP was observed also on back pain (P less than 0.05). We conclude that intermittent treatment with AHBuBP is capable of increasing spinal BMD and conserving radial BMD in postmenopausal osteoporosis and may represent a convenient therapeutic choice in this condition.

Histological evidence of increased turnover in bone from spontaneously hypertensive rats.

24 weeks-old spontaneously hypertensive male rats and normotensive genetic controls were subjected to: histomorphometry of the proximal tibiae, assay of mineral density of the femurs by dual photon absorptiometry, and measurement of the calcium content of the femoral bone ash by atomic absorption spectophotometry. Compared with the controls, the hypertensive rats showed osteopenia and increased bone turnover; their osteoid volumes and the surface area of both osteoclasts and osteoblasts were all increased. The data suggest that, during aging, spontaneously hypertensive rats both lose bone mass more rapidly and also have an increased skeletal metabolic rate with respect to the controls.

[Calcium folinate in old age]. / Il calcio folinato in età senile.

The authors report the results obtained in a group of 60 elderly patients (age greater than or equal to 65 years) treated with a 15 mg tablet of calcium folinate per day for 60 days. The drug was very well tolerated and it significantly improved the blood chemistry and clinical parameters considered.

[Comparison of HbA1c, fructosamine and the main metabolic parameters in a non-insulin-dependent diabetic population]. / Confronto tra HbA1c, fruttosamina e principali parametri metabolici in una popolazione di diabetici N.I.D.

Our objective was the checking of clinical data obtainable from the assay of some parameters in NID diabetic individuals. To this end, we studied 133 patients--57 males and 76 females, average age 74.36 +/- 1.01 years, 72.6% of which were above 65 years of age. The control population was subdivided as follows: 50 subjects, 26 F and 24 M; average age 71.25 +/- 1.32 years, with normal glucidic tolerance as assessed by OGTT. Current glycemia, average glycemia, fructosamine, glycosylated hemoglobin, triglycerides, LDL-cholesterol and apolipoprotein B were obviously much higher than normal in the individuals admitted to the study. A statistically significant correlation was found between average glycemia, glycosylated hemoglobin, LDL-cholesterol and blood triglycerides (p less than 0.05). No correlation was found between current glycemia, fructosamine and glycosylated hemoglobin. Similarly, serum fructosamine was unrelated to the parameters studied. In our study, fructosamine, glycosylated hemoglobin and current glycemia offered unrelatable data. Hence, in our opinion it is necessary to assay these three parameters contemporaneously for a reliable assessment of metabolic compensation.

Isotope retention for assessment of bone turnover in involutional osteoporosis.

A continuous bone remodelling takes place throughout life at different turnover speed according to age, physiological and pathological conditions. The evaluation of bone turnover may be of value for a prognostic and therapeutical assessment. Calcium bone exchange may be considered a suitable marker of bone turnover; for this reason 47Ca or 45Ca kinetics may be used; these methods have been employed in the past. Labelled diphosphonates, and in particular 99Technetium-methylene-diphosphonate (99TcmDP) are simpler and safer, because these substances are strongly and almost completely stored in bone and not absorbed by the soft tissue; for this reason they are used at the present time. The evaluation of blood levels and 24 hrs urinary elimination of 99TcmDP is used to measure whole bone diphosphonate retention (WBR). This parameter is positively correlated with other markers of bone turnover such as alkaline phosphatase (AP), osteocalcin (OC), urinary hydroxyproline (HOP). A bicompartmental analysis schedule of 99TcmDP distribution has been proposed some years ago and therefore applied by our group, based on the mathematical evaluation of serum concentration at different times and urinary elimination of the label given intravenously. This method provides the possibility to calculate not only WBR but also total body retention (TBR) and a constant (Kbh) which reflects the influx speed of the tracer in the bone. Kbh probably represents a more sensitive index of bone turnover than WBR. It presents a better correlation with AP and OC values and also shows some (statistically less significant correlations with some indices of bone remodelling obtained by histomorphometry on bone biopsies.(ABSTRACT TRUNCATED AT 250 WORDS)

Evaluation of whole blood filterability with increasing age in healthy men and women.

Whole blood filterability, expressed as volume of red blood cells filtered per minute (VRBC), was evaluated in 53 healthy men and 56 healthy women; in each sex, subjects were divided into 4 groups according to their age: adult age (20-50 yr.), advanced adult age (51-60 yr); presenile age (61-70 yr.) and senile age (greater than 70 yr.). In addition, plasma fibrinogen, PCV, white cell and platelet total counts were measured and correlated with VRBC. Whole blood filterability and plasma fibrinogen levels were also correlated with age. VRBC and PCV decreased, whereas fibrinogen levels increased with increasing age. VRBC values showed a significant negative correlation with age and plasma fibrinogen values; a significant positive correlation was found between fibrinogen levels and age. No other examined parameter changed with increasing age nor correlated with VRBC values. These findings indicate that with aging there are modifications of some rheological parameters, such as an increase in plasma fibrinogen levels and a decrease in whole blood filterability.

[Homeostasis of blood glucose and abuse of exogenous opiates: evaluation of fructosamine and glycosylated hemoglobin]. / Omeostasi glicemica ed abuso di oppioidi esogeni: valutazione della fruttosamina e dell'emoglobina glicosilata.

The study was designed to assess glycaemic homeostasis in different situations of chronic stimulation of the opiate receptors by exogenous opiates. After an OGTT, levels of glycosylated haemoglobin (HbA1c) and serum fructosamine were measured in 3 groups of male drug addicts of comparable age. Group A consisted of 10 subjects undergoing substitution treatment with oral methadone. Group B consisted of 10 subjects addicted to intravenous injection of the syrup based methadone intended for oral administration. Group C consisted of 10 heroin addicts. Ten healthy subjects of the same age and sex were used as controls. Analysis of the results showed normal glucose tolerance in all groups with tendentially higher basal glycaemia levels in group B. HbA1c levels were significantly higher, though within normal limits, in group B than in either those receiving oral methadone (p less than 0.01) or the heroin addicts (p less than 0.01). The group B subjects also showed the highest fructosamine levels that were both well above normal limits and higher than those in the other groups in whom fructosamine levels were normal. The data therefore confirm normal glycaemia compensation in those taking oral methadone and in heroin addicts during the period considered. A new type of drug addiction involving the intravenous injection of methadone was also encountered. This produces an outstanding short-term change in glycaemic homeostasis and may well lead to future alterations in glucose tolerance.