Effects of sublethal doses of silver nanoparticles on Bacillus subtilis planktonic and sessile cells.

AIMS: Due to their antimicrobial activity, silver nanoparticles (Ag-NPs) are being increasingly used in a number of industrial products. The accumulation of Ag-NPs in the soil might affect plant growth-promoting rhizobacteria and, in turn, the plants. We describe the effects of Ag-NPs on the soil bacteria Azotobacter vinelandii and Bacillus subtilis. METHODS AND RESULTS: In growth-inhibition studies, A. vinelandii showed extreme sensitivity to Ag-NPs, compared to B. subtilis. We investigated the effects of Ag-NPs at subinhibitory concentrations, both on planktonic and sessile B. subtilis cells. As determined by 2,7-dichlorofluorescein-diacetate assays, Ag-NPs increase the formation of reactive oxygen species in planktonic cells, but not in sessile cells, suggesting the activation of scavenging systems in biofilms. Consistently, proteomic analysis in B. subtilis Ag-NPs-treated biofilms showed increased production of proteins related to quorum sensing and involved in stress responses and redox sensing. Extracellular polysaccharides production and inorganic phosphate solubilization were also increased, possibly as part of a coordinated response to stress. CONCLUSIONS: At low concentrations, Ag-NPs killed A. vinelandii and affected cellular processes in planktonic and sessile B. subtilis cells. SIGNIFICANCE AND IMPACT OF THE STUDY: Re-direction of gene expression, linked to selective toxicity, suggests a strong impact of Ag-NPs on soil bacterial communities.

Patients with cancer who will be cured and projections of complete prevalence in Italy from 2018 to 2030.

BACKGROUND: The number and projections of cancer survivors are necessary to meet the healthcare needs of patients, while data on cure prevalence, that is, the percentage of patients who will not die of cancer by time since diagnosis, are lacking. MATERIALS AND METHODS: Data from Italian cancer registries (duration of registration ranged from 9 to 40 years, with a median of 22 years) covering 47% of the population were used to calculate the limited-duration prevalence, the complete prevalence in 2018, projections to 2030, and cure prevalence, by cancer type, sex, age, and time since diagnosis. RESULTS: A total of 3 347 809 people were alive in Italy in 2018 after a cancer diagnosis, corresponding to 5.6% of the resident population. They will increase by 1.5% per year to 4 012 376 in 2030, corresponding to 6.9% of the resident population, 7.6% of women and ∼22% after age 75 years. In 2030, more than one-half of all prevalent cases (2 million) will have been diagnosed by ≥10 years. Those with breast (1.05 million), prostate (0.56 million), or colorectal cancers (0.47 million) will be 52% of all prevalent patients. Cure prevalence was 86% for all patients alive in 2018 (87% for patients with breast cancer and 99% for patients with thyroid or testicular cancer), increasing with time since diagnosis to 93% for patients alive after 5 years and 96% after 10 years. Among patients who survived at least 5 years, the excess risk of death (1 - cure prevalence) was <5% for patients with most cancer types except for those with cancers of the breast (8.3%), lung (11.1%), kidney (13.2%), and bladder (15.5%). CONCLUSIONS: Study findings encourage the implementation of evidence-based policies aimed at improving long-term clinical follow-up and rehabilitation of people living after cancer diagnosis throughout the course of the disease. Updated estimates of complete prevalence are important to enhance data-driven cancer control planning.

Detection and distribution of culturable Human Enteroviruses through environmental surveillance in Milan, Italy.

AIMS: Human Enteroviruses (HEVs) infections have a significant impact on public health, being implicated in outbreaks of meningitis, encephalitis, hand-foot-mouth disease and other acute and chronic manifestation. In the strategic plan for poliomyelitis eradication, the environmental surveillance of poliovirus (PV) has been identified by the World Health Organization (WHO) as an activity that can complement the surveillance of polio. Having wastewater samples available for PV surveillance allows us to study nonpolio enteroviruses (NPEVs) circulating in the study population, which are widely spread. METHODS AND RESULTS: This study was carried out according to the WHO guidelines for environmental surveillance of PV and analysed the circulation of PV and NPEVs through the isolation of viruses in cell cultures in Milan area; from 2006 to 2010, 321 wastewater samples were collected, regularly over time, at the inlet of three diverse waste water treatment plants (WWTPs). Culturable HEVs were isolated in 80% of sewage samples: all isolates belonged to the HEV-B group and those circulating more intensely were CVB5 and Echo 6, while CVB4 was the predominant serotype found in 2010. In this study, two type 2 PVs were isolated, both characterized as Sabin like. CONCLUSION: Environmental monitoring of HEVs in Milan has proved to be an interesting tool to investigate the circulation and distribution of viruses. SIGNIFICANCE AND IMPACT OF THE STUDY: The detection of PV and other NPEV could be predictive of possible re-emergence of these viruses with an impact on public health. NPEV monitoring could also be a powerful public health tool to investigate the possible role of NPEV in different clinical manifestations.

Two unusual cases of pharyngeal hairy polyp causing intermittent neonatal airway obstruction.

Hairy polyp of the pharynx is an uncommon developmental malformation that is most frequently seen as a penduculated tumour in the neonate. The clinical presentation is characterized by the presence of a polypoid mass protruding through the mouth as 'a second tongue' causing respiratory distress. Two patients are presented with this condition.

Biochemical selectivity of oral versus intravenous aspirin in rats. Inhibition by oral aspirin of cyclooxygenase activity in platelets and presystemic but not systemic vessels.

In rats intravenous aspirin was only slightly more effective an inhibitor of platelet thromboxane B2 (TxB2) than of aorta 6-keto-prostaglandin (PGF)1 alpha generation (1.9 versus 2.1 mg/kg). In contrast, oral aspirin was about five times more effective on platelet than on aorta cyclooxygenase activity. The "biochemical selectivity" of aspirin as an inhibitor of platelet and vascular cyclooxygenase thus was not apparent after intravenous administration of the drug. However, this could be achieved by relatively low doses of oral (or intraduodenal) aspirin, on account of "presystemic" acetylation of platelet cyclooxygenase. Even in this condition, though, aspirin selectivity was relative to "systemic" peripheral vessels but not to the vessels of the enterohepatic circulation. Indeed after an oral or intraduodenal dose of 5 mg/kg aspirin, generation of portal vein 6-keto-PGF1 alpha was inhibited to much the same extent as platelet TxB2, while inferior vena cava 6-keto-PGF1 alpha formation was spared.

Median preoptic neurones are sensitive to blood pressure changes induced by peripheral angiotensin II.

The activity of 50 histologically identified neurones of the median preoptic area (MPO) was recorded simultaneously with blood pressure monitoring. The responsiveness of these neurones was investigated with increasing doses (25-100 ng/ml/kg) of intravenously applied angiotensin II (ANG II). Mean blood pressure rose in a dose-dependent manner (between 3.9 +/- 0.5 and 18.6 +/- 2.6 mm Hg) whereas the rise in firing frequency of MPO neurones (between 47 and 105% of spontaneous discharge) was not dose-related. The latency of neuronal response decreased according to the dose applied: at the lowest dose of angiotensin it was longer (105 +/- 20 s) than at the highest dose (26 +/- 8 s). These findings suggest that MPO neurones are sensitive to ANG II-haemodynamic changes.

Prolongation of rat tail bleeding time by ketanserin: mechanisms of action.

Serotonin (5-HT) may play a regulatory role in platelet-vessel wall interaction. This can be reliably investigated by measuring bleeding time. Ketanserin is a recently developed selective 5-HT2 receptor antagonist, reportedly effective against both platelet and vascular 5-HT activation. Ketanserin (5-10 mg/kg) significantly prolonged tail bleeding time measured in conscious rats by two different techniques. While mianserin (a 5-HT2 receptor antagonist exhibiting alpha-adrenolytic activity) also prolonged bleeding time, methysergide, metergoline and cyproheptadine did not. All three compounds acted as 5-HT2 receptor antagonists with appreciable affinity for 5-HT1 receptors. On the other hand, bleeding time was prolonged by either prazosin (a selective alpha 1-adrenoceptor antagonist) or labetalol (an alpha 1- and beta-receptor antagonist). In contrast it was not affected by phentolamine or nicergoline (alpha 1-alpha 2-receptor antagonists) nor by propranolol (a beta-receptor antagonist). The effect of prazosin was significantly increased by combining it with either ketaserin or metergoline. Depletion of platelet serotonin by reserpine did not result in any modification of bleeding time, unless reserpine was combined with an inhibitor of 5-HT synthesis. Platelet activation by 5-HT was neither potentiated by norepinephrine nor prevented by prazosin or phentolamine whereas ketanserin and methysergide were equally effective inhibitors. These findings argue against a role of platelet and/or vascular 5-HT2 receptors in the antihemostatic effect of ketanserin in rats. This drug prolongs bleeding time by antagonising vascular adrenoceptors (prazosin-like effect) and/or by preventing a synergistic interaction between 5-HT and catecholamines at the vascular level.

The lethal principle of Poa huecu (coiron blanco): a plant indigenous to Argentina.

The lethality of Poa huecu, a plant toxic to cattle and sheep, was followed by injection of chromatographic fractions in mice. The lethal aqueous extract was administered i.p. to Rockland mice of either sex and produced motor incoordination, transient ataxia, rough hair coat, tremors and muscle contractions and, occasionally, blindness. Doses greater than 1.5 g/kg mouse were always lethal. Fractionation of this lethal extract included dialysis, column chromatography on Sephadex G-25 and fractional precipitation with ethanol. Precipitates obtained with 70% and 85% ethanol were further purified on a DEAE-cellulose column. Eight fractions were obtained, each was injected into mice. Only fractions 3-6 were toxic. Fraction 3 produced slight hepatosis and hyperemia in the liver and gliosis in the brain. None of the other tissues exhibited histological lesions. Fractions 4 and 5 caused death of all animals within 30 min to 4 hr after injection. Polyacrylamide gel electrophoresis and acid hydrolysis showed that fractions 4 and 5 contained a glycoprotein of nearly the same mol. wt (67,000-94,000). Microscopic pathology in the mice treated with the lethal glycoprotein of fraction 4 included hyperemia in the kidneys, megakaryocytes in the spleen, slight hepatosis and focal coagulative necrosis with nuclear pyknosis and karyonexis in the liver, gliosis, intracellular brain edema with axon degeneration and swollen astrocytes in the brain. These brain injuries may relate to the motor incoordination of cattle that causes a delayed righting reflex. The major monosaccharides of the lethal glycoprotein are glucose and mannose, while rhamnose, arabinose, xylose and galactose are present in low percentages. Proline and the acidic amino acids (glutamic and aspartic acids) are the most abundant in the peptidic residue.

Agonist and antagonist properties of some benzomorphans on nociceptive reaction and intestinal transit in rats.

The agonist and antagonist properties of bremazocine, ethylketazocine, Mr 2034 and Mr 2092, benzomorphans with the same pharmacological actions in vitro, were studied in vivo in rats. Overnight fasted animals were tested for nociceptive reaction on a 55 degrees C hot-plate and for the intestinal transit of a charcoal meal fed 5 min earlier. The antagonist activity was assessed by the drugs' ability to prevent morphine-induced constipation. Bremazocine was an agonist on the nociceptive reaction and a pure antagonist on intestinal propulsion; ethylketazocine and Mr 2034 were pure agonists in both tests and Mr 2092 was a mixed agonist-antagonist in the intestinal transit test. Thus the in vivo agonist-antagonist properties of opiates cannot always be predicted from their in vitro characteristics.

Bremazocine induces antinociception, but prevents opioid-induced constipation and catatonia in rats and precipitates withdrawal in morphine-dependent rats.

Some in vivo agonist and antagonist properties of the putative k-compound bremazocine were characterized in rats. Bremazocine, at doses from 0.015-32 mg/kg i.p., delayed nociceptive reaction on a 55 degrees C hot-plate with a dose-response curve not readily fitting a single straight line; this effect was antagonized by high doses of naloxone. In the same rats bremazocine did not delay the intestinal transit of a charcoal meal fed 5 min earlier and prevented morphine-induced constipation. This antagonism appeared to be opioid-specific and competitive, with apparent pA2 value 8.56. Catatonia induced by etorphine (0.004 mg/kg s.c.) and constipation induced by etorphine (0.004 mg/kg s.c.) and D-Ala2-D-Leu5-enkephalin (0.1 mg/kg i.p.) were completely antagonized by bremazocine (0.03-8 mg/kg i.p.). Antinociception induced by morphine (10 mg/kg i.v.) and etorphine (0.004 mg/kg s.c.) was only partly prevented. Naloxone (1 mg/kg) and bremazocine (0.015-1 mg/kg i.p.) precipitated a withdrawal syndrome, evaluated as jumping frequency, in rats rendered dependent to morphine. These data suggest the involvement of more than one opioid receptor population in bremazocine action in vivo.

The opioid kappa-selective compound U-50,488H does not inhibit intestinal propulsion in rats.

The selective kappa-compound U-50,488H, at doses producing strong central pharmacological effects (0.5-32 mg kg-1 i.p.) did not delay the intestinal transit of a charcoal meal and had little or no antagonist action against morphine-induced constipation. It appears that kappa-opioid receptors are probably not involved in the mechanisms responsible for opioid-induced constipation.

[Osteodystrophy in thalassemia major]. / Osteodistrofia nella talassemia major.

Subjects with thalassemia major frequently have bone disorders of debatable pathogenesis. We attempt here to analyze the relationships between siderosis and thalassemic osteodystrophy by assessing calcium-phosphorus balance, hormone-vitamin homeostasis, osteoblastic-osteoclastic activity parameters, and bone mineral density (BMD) in 30 patients with thalassemia major (16 males, 14 females, age range 17-30 years). We found a significant increase in ferritin (p < 0.001) and significant decreases in serum i-PTH, 25OHD3, 1.25(OH)2D3, osteocalcin, estradiol, testosterone and FT4 (p < 0.001) in both sexes. In all patients a net decrease of bone mineral density was documented (p < 0.001). These results were then submitted to linear regression analysis: positive correlations between BMD and FT3, testosterone, estradiol (p < 0.01), were documented, and an inverse correlation between osteocalcin and ferritin was confirmed. Our findings suggest that thalassemic osteodystrophy is the result of several inhibitory influences on osteoblastic activity and bone apposition (related to hormone deficits and siderosis) which are aggravated further by anemia, chronic hypoxia and red marrow expansion.

An association of primary hyperparathyroidism and non medullary thyroid carcinoma.

A 40-year-old woman was admitted because of long-lasting asymptomatic hypercalcaemia. About 2 years earlier she underwent thyroidectomy and further 131 I therapy because of well-differentiated non medullary thyroid carcinoma. On admission biochemical data and hormonal values (serum calcium, serum phosphorus, i-PTH) were consistent with primary hyperparathyroidism; ultrasonography, computed tomography, thallium-technetium scintiscanning disclosed right paratracheal mass; on surgical procedure a right parathyroid adenoma was removed. The coexistence of non medullary thyroid carcinoma and primary hyperparathyroidism is rare: the prior 131 I therapy might be linked to subsequent development of parathyroid adenoma.

Hypothalamic pituitary adrenal function in patients with thalassemia major.

We examined the adrenocortical function in 14 italian thalassemic patients (8 f., 6 m.) aged 12 to 28. The following hormones were determined in each subject: plasma cortisol and aldosterone levels in both basal conditions and after maximal and submaximal stimulus (250 and 5 micrograms respectively) with synthetic corticotrophin beta 1-24 (Synacthen Ciba); corticotrophin and cortisol response to insulin-induced hypoglycaemia (0.15 U/kg iv.). Tests were repeated in all patients four years later. Normal controls were a group of 10 normal subjects matched for age, sex and body mass. Normal basal values of cortisol, aldosterone and ACTH were observed. Impaired cortisol response after stimulation with 5 micrograms of ACTH (6 patients) and after hypoglycaemia (4 patients) was identified. At the second test, four years later, one patient showed impaired cortisol response to both ACTH (5, micrograms) and hypoglycaemia, unlike the normal response to the first test. In all the others the cortisol response to stimulation did not differ from previous ones. In conclusion reduced ACTH and cortisol reserves detected in some thalassemic patients may be related to iron infiltration in the pituitary and adrenal glands. However, the present study did not indicate any significant correlation between either total blood load or serum ferritin and adrenal function parameters. Alteration in circulating hormones catabolism and impaired synthesis of transport proteins caused by chronic liver disease made adrenocortical hypofunction an even more complex picture to understand.

Hexavalent vaccines for immunization in paediatric age.

Despite the potential for protection against a broad spectrum of pathogens, the availability of an increased number of effective vaccines could lead to a significant reduction in vaccination coverage as the result of issues with implementation of new vaccines within existing protocols. To overcome these problems, the development of combined vaccines has been promoted. The use of combined vaccines offers a number of potential benefits, including a reduction in the number of patient visits, reduced complications associated with multiple intramuscular injections, decreased costs of stocking and administering separate vaccines, and a lowering of the risk of delayed or missed vaccinations. The hexavalent vaccine includes antigens against diphtheria, tetanus, acellular pertussis (DTaP), hepatitis B (HBsAg), poliomyelitis (P1, P2, P3) and Haemophilus influenzae type B (Hib) infections. The primary goal of this review is to discuss the immunogenicity, efficacy, safety and tolerability of several hexavalent preparations that are either commercially available or still under development.

Optometry and the underprivileged--an investigative report.

In this essay I have taken the topic, "Optometry and the Underprivileged," and approached it as an investigative report. This investigation found me talking with people in all walks of life and visiting many institutions and health care facilities. Some of the people discussed in the report and their conditions represent composites of the real situations I encountered. Their names are fictitious and to the best of my knowledge these people do not exist. The report is intended to be informative, constructively critical, unboring, and positive. If I have accomplished this, then my purpose has been fulfilled.

Morphogenesis and differentiation of Dictyostelium cells interacting with immobilized glucosides: dependence on DIF production.

Previous work has shown that multicellular morphogenesis of submerged Dictyostelium cells is inhibited when they bind to glucosides covalently linked to polyacrylamide gels. The amoebae aggregate normally, but then the aggregates repeatedly disperse and reaggregate, whereas control cells go on to form tight aggregates. We have investigated the role of the stalk cell differentiation inducing factors (DIFs) in this process. In the presence of cyclic AMP, amoebae submerged at high cell density accumulate DIF and differentiate into stalk cells. We find that stalk cell differentiation is inhibited by interaction of the cells with glucoside gels in these conditions, but can be restored by the addition of exogenous DIF-1. Since the responsiveness of cells to DIF-1 is not altered, it appears likely that the effect of the glucoside gel is to block DIF-1 production. Further, the addition of DIF-1 or DIF-2 stimulates the formation of tight aggregates by cells developing on glucoside gels in the absence of cyclic AMP, thus preventing the rounds of aggregation and disaggregation otherwise seen. This suggests a role for DIF in morphogenesis as well as in controlling cell differentiation. We propose a model in which immobilized glucosides activate a specific receptor ("food sensor") which drives the amoebae toward the vegetative state and inhibits DIF accumulation. DIF, on the other hand, induces tight aggregate formation and so locks the amoebae into the developmental program.

EMG activity of pigeon oesophagus in vivo.

At rest, the pigeon cervical oesophagus, which is entirely smooth muscle, shows electric activity. This activity consists of bursts of spikes with frequency increasing in the oral-aboral direction. The bursts are un-phase locked, and there are no slow waves (E.C.A.). The surgical transection of the oesophageal muscular wall does not affect the electric activity even in a disconnected segment. After asphyxia electric activity persists, whereas the aboral gradient of frequency disappears. Therefore, the electric activity is thought to be myogenic in origin, and the frequency gradient nervous in origin. Atropine and neostigmine administration suggests that the cholinergic system modulates the electric activity, but it is not involved in the control of the frequency gradient. On the contrary, hexamethonium administration, by abolishing this gradient, lends support to the idea of a postganglionic atropine-resistant neuronal system responsible for the gradient.

[Esophageal EMG activity in the pigeon (Columbia livia) in vivo]. / Attività EMG dell'esofago di piccione (Columba livia), in vivo.

The pigeon esophageal smooth muscle shows "spontaneous" rhythmic bursts of spikes with increasing discharge frequency from pharynx to crop. There are no slow waves. The changes of the electric pattern induced by pharmacological administrations of atropine, prostigmine, hexamethonium and by asphyxia suggest that the electric activity is myogenic in origin. The innervation plays a role in the control of this activity and it is essential for the functional polarization.