Synthesis and characterization of an experimental primer containing chitosan nanoparticles - Effect on the inactivation of metalloproteinases, antimicrobial activity and adhesive strength.

OBJECTIVE: The aim of this study was to synthesize and characterize an experimental primer containing cationic lipid nanoparticles (NPL-chitosan) and to evaluate its properties. DESIGN: The NPL-chitosan were synthesized by emulsion and sonication method. The experimental primers were applied in dentin surface of fifty human molars. The experimental groups were: 1) application of commercial primer; 2) Primer containing 2% of Chlorhexidine (CHX) 3); Primer with 2% NPL-chitosan 4); Primer with 0.6 % of NPL-chitosan 5); Primer with 0.4 % of NPL-chitosan. A composite resin plateau was used for the analysis, where sections were made for making the dentin beams. The effect of experimental primer with cationic nanoparticles in the inhibition of matrix metalloproteinase (MMP) activity was carrying out by in situ zymography. For the Resin-Dentin Adhesive Strength and in situ Zymography analysis, was used the One-way analysis of variance (ANOVA) with significance level of 95 %. RESULTS: Spherical NPL-chitosan presented size below 220 nm, polydispersity index of 0.179 and zeta potential positive and was stable over 75 days. These nanoparticles showed antibacterial activity agsainst S. mutans with MIC of the 0.4 % and MBC of 0.67 %. In the Microtensile Strength, no statistical difference was observed between the experimental groups (p = 0.9054). The in situ zymography assay showed that the group with 2% of NPL-chitosan presented higher inactivation activity of MMPs compared to the other groups (p < 0.05). CONCLUSION: The experimental primer containing NPL-chitosan has antimicrobial activity, does not alter the adhesive resistance and inactivates MMPs present in dentin.

Genetic Polymorphisms in ACTN3 Contribute to the Etiology of Bruxism in Children.

Objective: Bruxism is a condition defined as a masticatory muscle activity with an unexplored genetic background. The aim of this study was to evaluate the association between genetic polymorphisms in ACTN3 and bruxism. Study design: A total of 151 biological-unrelated children, aged 7-12 years were included in a case control ratio of 1:1.5. The data collection was performed during interview and clinical examination. Saliva samples were collected from all children and 3 genetic polymorphisms in the ACTN3 (rs678397, rs1671064 and rs1815739) were selected for genotyping using real time PCR. Pearson chisquare calculation was used to assess Hardy-Weinberg equilibrium and to evaluate the association between genotypes and alleles frequencies for each genetic polymorphism in the co-dominant and recessive models. An alpha of 5% was used. Results: The genetic polymorphisms rs678397, rs1671064 and rs1815739 were associated with bruxism in the co-dominate model and in the recessive model (p<0.05). Allele distribution was also associated with bruxism for the polymorphisms rs678397 and rs1671064 (p<0.05). Conclusion: The genetic polymorphisms rs678397, rs1671064 and rs1815739 in ACTN3 are associated with bruxism and can contribute to the etiology of this condition in children.

Short-term surgical outcomes and histomorphological evaluation of thermal injury following palatoplasty performed with diode laser or air plasma device in dogs with brachycephalic airway obstructive syndrome.

Brachycephalic obstructive airway syndrome (BOAS) is a common disorder presenting enlarged soft palate, stenotic nares and abnormal turbinate growth. Surgical correction of BOAS abnormalities with caudal palatoplasty is an elective therapy. This prospective study aimed to compare the effect of an air plasma device and diode laser in dogs undergoing palatoplasty. Outcome measures were as follows: (1) intra-operative and immediate post-operative complications; (2) evaluation of thermal injury in histological tissue sections of the excised soft palate. Twenty dogs with enlarged soft palates underwent palatoplasty, using an air plasma device (n=10) and diode laser (n=10). Soft palate specimens underwent masked histopathological analysis to assess post-operative thermal injury. In this pilot study, no differences were observed in surgical times; all dogs were discharged 24h after surgery and had stable respiration. In the air plasma group, post-operative bleeding occurred in two cases and revision surgery was performed. No difference in thermal injury was observed using the two devices (P>0.05). The air-plasma device was a viable surgical option for palatoplasty in dogs with BOAS.

Molecular characterization and confocal laser scanning microscopic study of Pygidiopsis macrostomum (Trematoda: Heterophyidae) parasites of guppies Poecilia vivipara.

Pygidiopsis macrostomum and Ascocotyle (Phagicola) pindoramensis (Digenea: Heterophyidae) parasitize guppies as intermediate hosts and, respectively, fish-eating mammals or birds as definitive hosts. Heterophyids have zoonotic potential, and molecular studies associated with morphological and ecological aspects have helped to clarify their taxonomy and phylogeny. Poecilia vivipara naturally parasitized by metacercariae of both species (100% prevalence) exhibit no external signs of parasitism. In this work, four new sequences of P. macrostomum (18S rDNA, 28S rDNA and ITS2 rDNA) and one new sequence of A. (P.) pindoramensis (mtDNA cox-1) are presented. Phylogeny reconstructions linked P. macrostomum to other heterophyids, but the separation of the Heterophyidae and Opisthorchiidae remains unclear. Additionally, we used indirect immunocytochemistry and the phalloidin-fluorescence techniques allied with confocal laser scanning microscopy to describe muscular and neuronal structures of P. macrostomum. A complex arrangement of muscular fibres is associated with the tegument, suckers, gut and reproductive system. Radial fibres around the ventral sucker are thick, branched and extend to the body wall. High-resolution confocal imaging revealed a typical digenean muscular arrangement and important heterophyid morphological traits. These data will support future control measures to reduce the parasitism in guppies reared in fish farming systems, especially for aquarium and experimental purposes.

Redundant arytenoid mucosa: clinical presentation, treatment and outcome in three cats.

Three cats showing chronic, intermittent respiratory distress associated with increased noise on inspiration were examined. Head, neck and thoracic radiographs were unremarkable and laboratory findings were within normal ranges. In all three cats direct laryngoscopy revealed bilateral redundant arytenoid mucosa, which collapsed into the supraglottic and glottis airways during inspiration. Temporary tracheostomy and endoscopic diode laser excision of the excessive mucosa resolved symptoms in all three cats. Redundant arytenoid mucosa is a rare condition that may cause signs similar to laryngeal paralysis or laryngeal mass in cats. According to our results, diode laser surgery in association with temporary tracheostomy appears an appropriate mode of therapy.

Determination of breath alcohol value after using mouthwashes containing ethanol in healthy young adults.

OBJECTIVE: To evaluate breath alcohol value and blood alcohol concentration after using mouthwashes containing ethanol in a panel of healthy young adults. To determine zeroing time of these values and if subjects' body mass index or gender influenced it. Breathalyzer test is a practice performed to detect alcohol-impaired-drivers that can be penalized. Sometimes Italian judges revoke the penalty justifying that the presence of residual ethanol in the oral cavity can cause false positive values. PATIENTS AND METHODS: Our study involved 40 young adult volunteers; the cohort was composed of University students aged between 21 and 30 years. They underwent a medical examination to evaluate BMI. We selected four alcoholic mouthwashes available on the market with a different ethanol amount and an ethanol/ water (10/90) mixture as a reference. Breath alcohol concentration values were collected using a portable breathalyzer immediately after the rinse (T0), after 10 and 20 minutes (T10 and T20). We evaluated blood alcohol concentration 5 minutes after the rinse. RESULTS: All T10 values are lower than 0.5 g/L (Italian BAC driving limit). Differences between average values at T0-T10 are statistically significant (p < 0.05). Correlations between BAV and BMI are not statistically significant respectively at T0 (A: p = 0.54. B: p = 0.96. C: p = 0.93. D: p = 0.53) and T10 (A: p = 0.42. C: p = 0.99. D: p = 0.66). Differences between male and female groups aren't statistically significant (A: p = 0.49; B: p = 0.79; C: p = 0.97; D: p = 0.06). CONCLUSIONS: High BAV values determined at T-0 are a consequence of residual ethanol present in the oral cavity, the zeroing time of these ones (oppure thereof) is very swift. Our study shows that rinsing with an alcoholic mouthwash before undergoing the breathalyzer test does not realistically influence the result.

Regeneration potential and survival of transplanted undifferentiated adipose tissue-derived stem cells in peripheral nerve conduits.

Adipose tissue-derived stem cells (ADSCs) have shown potential for the treatment of nerve injuries. Most previous efforts have aimed at stimulating regeneration by using neural-differentiation protocols, but the potential of undifferentiated ADSCs to enhance axonal growth as well as their ability to transdifferentiate in situ have been poorly investigated. In this study, using a rat sciatic nerve model we show that ADSCs, transplanted in an artificial nerve conduit, stimulate axonal outgrowth from the proximal nerve stump and evoke greater Schwann cell (SC) proliferation/intrusion in the distal stump. To track the fate of the transplanted cells, we used green fluorescent protein (GFP)-labelling and polymerase chain reaction (PCR) for the detection of the sex determining region Y (SRY) gene in the donor male cells. Both methods indicated a lack of significant quantities of viable cells 14 days after transplantation. These results suggest that any regenerative effect of transplanted ADSCs is more likely to be mediated by an initial boost of released growth factors and/or by an indirect effect on endogenous SCs activity. Future studies need to address long-term cell survival in tissue-engineered nerve conduits to improve the neuroregenerative potential of ADSCs.

Fibrin matrix for suspension of regenerative cells in an artificial nerve conduit.

Peripheral nerve injury presents with specific problems of neuronal reconstructions, and from a clinical viewpoint a tissue engineering approach would facilitate the process of repair and regeneration. We have previously used artificial nerve conduits made from bioresorbable poly-3-hydroxybutyrate (PHB) in order to refine the ways in which peripheral nerves are repaired and reconnected to the target muscles and skin. The addition of Schwann cells (SC) or differentiated mesenchymal stem cells (dMSC) to the conduits enhances regeneration. In this study, we have used a matrix based on fibrin (Tisseel) to fill optimally the nerve-conduits with cells. In vitro analysis showed that both SC and MSC adhered significantly better to PHB in the presence of fibrin and cells continued to maintain their differentiated state. Cells were more optimally distributed throughout the conduit when seeded in fibrin than by delivery in growth medium alone. Transplantation of the nerve conduits in vivo showed that cells in combination with fibrin matrix significantly increased nerve regeneration distance (using PGP9.5 and S100 distal and proximal immunohistochemistry) when compared with empty PHB conduits. This study shows the beneficial combinatory effect of an optimised matrix, cells and conduit material as a step towards bridging nerve gaps which should ultimately lead to improved functional recovery following nerve injury.

Neuronal survival, regeneration and musclemorphology after posterior C7 nerve transfer: an experimental study.

C7 nerve transfer has been widely used in treating brachial plexus avulsion injuries. Little is known regarding the survival and regeneration of C7 motor and sensory neurons including their morphological changes after this procedure and also the possible change of muscle fibre phenotype. In this experimental study, the posterior division of C7 nerve was transferred to the musculocutaneous nerve ipsilaterally, and using fluorescent tracing techniques, the C7 spinal cord segment and dorsal root ganglion were found to contain 630.9 +/- 86.7 motor neurons and 3916.0 +/- 517.3 sensory neurons, respectively. Six months following transfer, 90% of the motor neurons and 78% of the sensory neurons survived and approximately 40% of them had regenerated and all displayed normal soma size. After posterior C7 transfer and reinnervation, the target muscles showed a percentage pattern of distribution and mean fibre diameters similar to those seen in normal biceps muscle. The present study suggests that the posterior C7 nerve transfer provides sufficient number of neurons and satisfactory results for regeneration to obtain an acceptable functional recovery.

[Syncope and work. STePS study (Short Term Prognosis of Syncope)]. / La sincope in età lavorativa. Studio multicentrico prospettico STePS.

BACKGROUND: Recurrent syncope is a common medical problem responsible for 3-5% of emergency department (ED) accesses and 1-6% of hospital admissions. If syncope occurs in a subject working in a critical safety task, the consequences of this event might be very dangerous for the worker, colleagues, others or for the environment. Therefore, syncope management is a major problem for occupational medicine, converning the general safety at work. AIMS: To evaluate the syncope events in a group of potential workers aged 18 to 65 years; to evaluate the symptoms preceding syncope and the presence of associated illnesses and recurrent events. POPULATION AND RESULTS: This study is part of the prospective study STePS (Short Term Prognosis of Syncope), and included 305 consecutive patients (aged 18-65 years, female 56%) who had syncope as a main symptom and presented at ED of four general hospitals in the Milan area, Italy, between the 23rd of January and 30th of June 2004. The 24% of subjects were hospitalized. In 21% the syncope occurs suddenly without any preceding symptom. The 67% of subjects didn't have any important illness at the time. 50% of subjects had recurrent syncope. In four subjects another syncope occurred in a 10 day follow-up. CONCLUSIONS: occupational medicine should consider syncope scrupulously. Proper diagnostic management is important to permit a correct evaluation of work safety issues.

Quantification of N-CAM and N-cadherin expression in axotomized and crushed rat sciatic nerve.

Adhesion molecules are important in supporting axonal regeneration. Qualitative studies have described increased expression of neural cell adhesion molecule (NCAM) and N-cadherin in models of nerve injury allowing active regeneration. In this study we have used quantitative immunohistochemistry to compare expression of NCAM and N-cadherin after nerve injury either with active regeneration (crush) into the distal stump or without (axotomy and capping). Quantification was performed 15 days after axotomy in proximal and distal stumps. Quantification after crush either proximal, distal or within the crushed area was performed at 2, 7, 15 and 30 days after injury. Axotomy induced increases in expression in proximal stumps between two and three times those in uninjured nerves for both molecules. In distal stumps, N-cadherin levels increased seven-fold, yet NCAM levels did not exceed control values. After crush, NCAM immunoreactivity increased in the crushed area and distal stump in contrast to axotomy and NCAM-positive axons co-localized with PGP9.5. N-cadherin levels in the distal stump increased above control levels, but the magnitude of the increase seen after crush was different to those seen after axotomy. In conclusion, increased expression of adhesion molecules, particularly NCAM, in the distal stump of injured nerves is dependent upon the presence of regenerating axons.

[Urinary hexafluoroisopropanol in the assessment of occupational exposure to sevoflurane: methodologic features and critical points]. / L'esafluoroisopropanolo urinario nella valutazione dell'esposizione professionale a sevofluorano: aspetti metodologici e punti critici.

The increasing use of sevoflurane as anaesthetic leads to the need for finding a biological index to evaluate the occupational exposure in surgical activity. Several studies indicate that Hexafluoroisopropanol (HFIP) is a specific sevoflurane metabolite quickly glucuronidated and excreted as HFIP-glucuronide in the urine (HFIPu). Therefore the HFIP removal kinetics in occupational exposure and the correlation between sevoflurane exposure and HFIPu are poorly understood. We studied no. 86 operating room workers of Novara Hospital to evaluate the correlation between the sevoflurane individual exposure (SE) and the HFIPu at the end of the shift expressed in microgram/L (A-HFIPu) and in microgram/g creat. (C-HFIPu). Therefore, in the same group of subjects we evaluated the HFIPu in the urine sampled at 8.00 a.m. before the work. The correlation coefficient was R2 = 0.782 (p < 0.0001) for SE/A-HFIPu and R2 = 0.862 (p < 0.0001) for SE/C-HFIPu; HFIPu normalized for urinary creatinine (C-HFIPu) is an index more suitable than the A-HFIPu. Furthermore we concluded for the usefulness of pre-shift HFIPu.

Efficacy of varying concentrations of hyaluronidase in peribulbar anaesthesia.

We have compared the efficacy of adding varying concentrations of hyaluronidase to a standard mixture of 2% lidocaine and 1% ropivacaine to provide peribulbar anaesthesia for cataract surgery. We used (i) the time to adequate anaesthesia for surgery and (ii) ocular and eyelid movement scores at 8 min after block as clinical endpoints. Ninety patients were randomly allocated to receive 7-10 ml of equal volumes of 2% lidocaine and 1% ropivacaine without hyaluronidase or with hyaluronidase 15 IU ml(-1) or 150 IU ml(-1). Median time at which the block was adequate for surgery was 6 min in all groups (interquartile range 4-12 min). Median eyelid movement scores were similar in all groups, but the ocular movement scores at 8 min were significantly lower in the group which received hyaluronidase 150 IU ml(-1) than in the group not given hyaluronidase (P<0.03). There were no differences between groups in the incidence of minor complications. A high concentration of hyaluronidase resulted in a statistically significantly lower ocular movement score at 8 min; the clinical relevance of this finding is uncertain.

Cancer mortality among rice growers in Novara Province, northern Italy.

Some excess of non-Hodgkin lymphomas (NHL) and soft tissue sarcomas (STS) was reported in the literature among agricultural workers, mainly in relation to exposure to phenoxyacids and chlorophenols. In this study, information was analyzed for a cohort of rice growers that comprised 1,493 subjects, and for a follow-up that was more than 99% complete with regard to both traced subjects and known causes of deaths. A total of 960 subjects (65%) died during the observation period (1957-1992). Lower than expected standardized mortality ratios (SMRs) were found for all causes, for cardiovascular diseases (especially ischemic heart disease) and for all cancers. Slightly increased SMRs were found for some cancer sites (oral cavity, esophagus, liver, intestines, pancreas, bladder, STS, and NHL), although none of these was statistically significant in the overall analysis. An excess risk of close to statistical significance was found for NHL among workers with longer exposure during the period when phenoxyacid herbicide was in use (1950-1992). Thus, a prolonged follow-up is advisable. At present the study should be evaluated in the context of the data set suggesting a tendency toward an increased risk of NHL among farmers.

Effect of restricted and ad libitum feeding on semen production and fertility in broiler breeder males.

1. The effect of food restriction on the quality of semen production and fertility in broiler breeder males was studied. 2. Seventy-two Ross broiler breeder males, from 20 to 54 weeks of age, were divided into 4 groups and fed as follows: group 1 = 110 g/bird/d; group 2 = 120 g/bird/d; group 3 = 130 g/bird/d; group 4 = ad libitum. 3. Body weight, sperm quality (volume, concentration, % motility and % live cells) and fertility were measured. The birds were slaughtered at 55 weeks of age; the abdominal fat pad and testicles were weighted. 4. Groups 2 and 3 produced the highest volume of semen. The quality of semen was very similar in all the restricted groups. 5. Males fed ad libitum produced semen with the best motility and percentage of live cells. Groups 3 and 4 showed the best fertility percentage (79%) against group 1 and 2 (59 and 72% respectively).

Heritabilities and genetic correlations of conformation and plumage characteristics in pheasant (Phasianus colchicus).

Data were obtained from 588 pedigreed pheasants of an unselected population. Body weight, shank length (SL), plumage measurements, and plumage score were analyzed to estimate heritabilities and genetic and phenotypic correlations. All measurements were made at 28 and 120 d of age. The h2 estimates (sire component) were the following: .27 and .30 for BW at 28 (BW28) and at 120 d (BW120), respectively; .34 and .79 for SL at 28 (SL28) and at 120 d (SL120), respectively; .30 and .13 for rectrices length (RL) at 28 (RL28) and at 120 d (RL120), respectively; .14 for primary remex at 28 d (PR); .21 for primary remex 1 at 28 d (PR1); .23 for secondary remiges length (SRL); .34 for body weight gain (BWG); .35 for shank length gain (SLG). Negative genetic correlations between BW and SL with plumage traits at 120 d were found. The magnitude of heritability indicates that selection for BW is possible but the negative association with plumage traits must be carefully considered. The improvement of housing conditions could lead to birds with a well-developed plumage, because environment influenced variability of plumage traits.

Evaluation of pheasant semen production during the reproductive season.

The aim of this research was to evaluate the quality and quantity of semen production of pheasants during the reproductive season. Fifty-five male pheasants (Phasianus colchicus mongolicus) were used from 37-59 weeks of age. Semen samples were collected manually on a biweekly basis. At 45 weeks of age, pheasants which had never produced (n = 22) or only produced occasionally (n = 7) were discarded from the study. The volume of the ejaculate from each male was measured upon each semen collection. Sperm concentration and motility were measured for every semen collection from the 41st week of age. Body weight was recorded at 38 and 39 weeks and then every 2 weeks. The largest percentage (55%) of males producing semen was reached at 44 weeks of age. Semen variables showed the following mean values during the reproductive season: volume = 105 mg, concentration = 5.86 x 10(9)/ml, and motility scale = 2.45 (modest-good). Semen variables were significantly influenced by bird and age but not by day of collection.

[Anesthetic gases and neuropsychological tests]. / Gas anestetici e test neuropsicologici.

The Authors observed, in a group of 15 subjects working in operating theatres and occupationally exposed to anesthetic gases, an increase of simple reaction average times and an increase of the latency of the wave V of the brainstem auditory evoked potentials. The small number of subjects doesn't allow to draw conclusions. Nevertheless the findings agree with first analogous studies. The Authors, therefore, think opportune to continue the research to acquire further evidence and to ascertain the validity of the current TLV.