First evidence of Kunjin strain of West Nile virus associated with saltwater crocodile (Crocodylus porosus) skin lesions.

Recently, the Kunjin strain of West Nile virus (WNVKUN ) has been detected using qRT-PCR in belly skin lesions of farmed juvenile saltwater crocodiles. This follows an established association between similar lesions and West Nile virus in American alligators. The lesions present as cutaneous lymphohistiocytic aggregates in the dermal layers of both species. While these lesion do not create an obvious defect on the live crocodile, upon tanning the lesion area collapses and does not uptake the dye evenly, thus reducing its aesthetic appeal. As a result, skins are being rejected jeopardising the economic viability of the Australian crocodile industry. Over 50 skin lesions have since been confirmed as WNVKUN -positive and preliminary evidence of lesion restructuring is presented. Horizontal transmission of WNVKUN by mosquitoes is well-established but other transmission routes, such as ingestion and cloacal shedding, need further evaluation. An infection trial is currently underway to ensure WNVKUN is the causative agent of these skin lesions.

Ventral hernia repair outcomes predicted by a 5-item modified frailty index using NSQIP variables.

PURPOSE: Frailty is a decrease in physiologic reserve that is separate from the normal aging process. Previously, an 11-item modified frailty index (mFI) using NSQIP variables predicted outcomes for surgical patients. We aim to validate a condensed 5-item mFI in ventral hernia patients and determine outcomes and the relative impact of each frailty variable. METHODS: The NSQIP database was queried from 2011 to 2016 for patients undergoing VHR. Spearman's rho correlation was used to determine the degree of correlation between 11-item and 5-item mFI raw frailty scores. Chi squared testing was used to determine odds ratios (95% CI) for accumulating frailty variables in both indices with regard to complications vs a baseline of zero variables present on the 11-item scale. Complications were defined by the Clavien-Dindo (CD) classification. Univariate and multivariate analyses were performed on each frailty variable to determine their relative weighted impacts on outcomes. RESULTS: 97,905 patients (99.45%) had all five frailty variables recorded. Only 11,549 patients (11.73%) had all variables from the 11-item mFI. No difference existed between groups for the five mutually shared frailty variables, BMI, emergent vs non-emergent procedures, operative time, or operative approach. For accumulating variables in both indices, the 5-item mFI predicts incidence of any complications, major complications, and discharge not to home similarly to the 11-item mFI. The most significantly weighted variable for complications and discharge not to home is functional status. CONCLUSION: A 5-item mFI accurately predicts outcomes similar to the validated 11-item mFI and captures more patients for analysis.

Impact of operative duration on postoperative pulmonary complications in laparoscopic versus open colectomy.

BACKGROUND: Prolonged operative duration is associated with increased postoperative morbidity and mortality. Although laparoscopic colectomy (LC) is associated with longer operative duration compared with open colectomy (OC), research shows paradoxically decreased morbidity following LC versus OC. The direct impact of operative duration on postoperative pulmonary complications (PPC) following LC versus OC has not been analyzed. METHODS: We queried the ACS/NSQIP 2009-2010 Public Use File for patients who underwent elective LC and OC. The associations between operative duration and a PPC (pneumonia, intubation >48 h, and unplanned intubation) were evaluated. Multivariable regression models were created to determine the independent effect of operative time on the development of PPC controlling for LC versus OC. RESULTS: A total of 25,419 colectomies (13,741 laparoscopic and 11,678 open) were reviewed; 765 (3 %) patients experienced at least one PPC. Regression modeling demonstrated that for both LC and OC each 60-min increase in operative time up to 480 min was associated with 13 % increased odds of PPC [odds ratio (OR) 1.13; 95 % confidence interval (CI) 1.07-1.19]. Beyond 480 min, each additional 60-min interval was associated with 33 % increased risk of PPC (OR 1.33; 95 % CI 1.12-1.58). Overall, PPCs occurred half as often following LC [270 (2 %) laparoscopic vs. 497 (4.3 %) open; OR 0.45; 95 % CI 0.39-0.53]. CONCLUSIONS: Operative duration is independently associated with increased risk of PPC in patients undergoing LC and OC. However, a laparoscopic approach carries half the absolute risk of PPC and, when safe, should be preferentially utilized despite a potential for prolonged operative duration.

Incidence and prevalence of copper deficiency following roux-en-y gastric bypass surgery.

INTRODUCTION AND OBJECTIVES: The frequency of copper deficiency and clinical manifestations following roux-en-y gastric bypass (RYGB) surgery is not yet clear. Objectives were to determine the prevalence and incidence of copper deficiency in patients who have undergone RYGB. DESIGN AND METHODS: We sought to determine the number of RYGB patients undergoing medical and nutritional follow-up visits at the Emory Bariatric Center who experienced copper deficiency and associated hematological and neurological complaints (n=136). Separately, in patients followed longitudinally before and during 6 and 24 months following RYGB surgery, we obtained measures of copper status (n=16). Systemic blood cell counts and measures of copper, zinc and ceruloplasmin were determined using standardized assays in reference laboratories including atomic absorption spectrometry and immunoassays. RESULTS: Thirteen patients were identified to have copper deficiency suggesting a prevalence of copper deficiency of 9.6%, and the majority of these had concomitant complications including anemia, leukopenia and various neuro-muscular abnormalities. In the longitudinal study, plasma copper concentrations and ceruloplasmin activity decreased over 6 and 24 months following surgery, respectively (P<0.05), but plasma zinc concentrations did not change. A simultaneous decrease in white blood cells was observed (P<0.05). The incidence of copper deficiency in these subjects was determined to be 18.8%. CONCLUSIONS: The prevalence and incidence of copper deficiency following RYGB surgery was determined to be 9.6% and 18.8%, respectively, with many patients experiencing mild-to-moderate symptoms. Given that copper deficiency can lead to serious and irreversible complications if untreated, frequent monitoring of the copper status of RYGB patients is warranted.

Do recurrences after paraesophageal hernia repair matter? : Ten-year follow-up after laparoscopic repair.

BACKGROUND: The recurrence rate for paraesophageal hernias (PEH) can be as high as 30% following laparoscopic repair. The aim of this study was to determine the severity of symptoms in patients with recurrences and the need for reoperation 10 years after surgery. METHODS AND PROCEDURES: Consecutive laparoscopic paraesophageal cases performed at a single institution between 1993 and 1996 were identified from the institution's foregut database. Patients were asked about the presence and severity of symptoms (heartburn, chest pain, regurgitation, and dysphagia). Patients were also asked whether they had (1) been diagnosed with hernia recurrence or (2) undergone repeat surgical intervention. RESULTS: Complete follow-up was obtainable in 31 of the total of 52 patients (60%). The proportion of patients reporting moderate/severe symptoms was less at 10 years than preoperatively: heartburn 12% versus 54% (p < 0.001), chest pain 9% versus 36% (p = 0.01), regurgitation 6% versus 50% (p < 0.001), and dysphagia 3% versus 30% (p = 0.001). Two patients underwent repeat surgical intervention for symptomatic recurrences within the first postoperative year. Eight more patients have been diagnosed with hernia recurrences on either contrast esophagram or upper endoscopy but had not required reoperation. At ten years, more patients with hernia recurrence had heartburn than those who did not have recurrences (60% versus 14%; p < 0.05). CONCLUSIONS: Despite a hiatal hernia recurrence rate of 32% 10 years after surgery, laparoscopic PEH was a successful procedure in the majority of patients; most remained symptomatically improved and required no further intervention 10 years after surgery.

Nasal administration of an angiotensin antagonist in the rat model: effect of bioadhesive formulations on the distribution of drugs to the systemic and central nervous systems.

The effect of bioadhesive formulations on the direct transport of an angiotensin antagonist drug ((14)C-GR138950) from the nasal cavity to the central nervous system was evaluated in a rat model. Three different bioadhesive polymer formulations (3% pectin LM-5, 1.0% pectin LM-12 and 0.5% chitosan G210) containing the drug were administered nasally to rats by inserting a dosing cannula 7mm into the nasal cavity after which the plasma and brain tissue levels were measured. It was found that the polymer formulations provided significantly higher plasma levels and significantly lower brain tissue levels of drug than a control, in the form of a simple drug solution. Changing the depth of insertion of the cannula from 7 to 15mm, in order to reach the olfactory region in the nasal cavity significantly decreased plasma levels and significantly increased brain tissue levels of drug for the two formulations studied (1.0% pectin LM-12 and a simple drug solution). There was no significant difference between the drug availability for the bioadhesive formulation and the control in the brain when the longer cannula was used for administration. It is suggested that the conventional rat model is not suitable for evaluation of the effects of bioadhesive formulations in nose-to-brain delivery.

Distribution and clearance of bioadhesive formulations from the olfactory region in man: effect of polymer type and nasal delivery device.

There is an increasing need to identify novel approaches by which to improve the efficiency of drug transport from the nasal cavity (olfactory region) to the CNS, especially for treatment of central nervous system disorders. It is suggested, that one approach is the combination of active targeting of a bioadhesive formulation, that will retain the drug at the absorption site, potentially in combination with, an absorption enhancer. Two low methylated pectins, LM-5 and LM-12 were selected for evaluation as drug delivery systems, due to their ability to gel in the nasal cavity and their bioadhesive characteristics, together with chitosan G210, which acts both as a bioadhesive material and as an efficient absorption enhancer. It was found that all of the bioadhesive formulations were able to reach the olfactory region in the nasal cavity of human volunteers when delivered using a simple nasal drop device. Furthermore, the formulations displayed a significantly increased residence time on the epithelial surface. This was in contrast to a non-bioadhesive control delivered with the same device. In contrast, a pectin formulation administered with a nasal spray system did not show an increase in residence time in the olfactory region. It was further shown that the reproducibility of olfactory delivery of a polymer formulation was significantly better intra-subject than inter-subject.

Evaluation of bioadhesive polymers as delivery systems for nose to brain delivery: in vitro characterisation studies.

There is an increasing need for nasal drug delivery systems that could improve the efficiency of the direct nose to brain pathway especially for drugs for treatment of central nervous system disorders. Novel approaches that are able to combine active targeting of a formulation to the olfactory region with controlled release bioadhesive characteristics, for maintaining the drug on the absorption site are suggested. If necessary an absorption enhancer could be incorporated. Low methylated pectins have been shown to gel and be retained in the nasal cavity after deposition. Chitosan is known to be bioadhesive and also to work as an absorption enhancer. Consequently, two types of pectins, LM-5 and LM-12, together with chitosan G210, were selected for characterisation in terms of molecular weight, gelling ability and viscosity. Furthermore, studies on the in vitro release of model drugs from candidate formulations and the transport of drugs across MDCK1 cell monolayers in the presence of pectin and chitosan were also performed. Bioadhesive formulations providing controlled release with increased or decreased epithelial transport were developed. Due to their promising characteristics 3% LM-5, 1% LM-12 pectin and 1% chitosan G210 formulations were selected for further biological evaluation in animal models.

Heating and humidifying of carbon dioxide during pneumoperitoneum is not indicated: a prospective randomized trial.

BACKGROUND: Carbon dioxide (CO2) pneumoperitoneum usually is created by a compressed gas source. This exposes the patient to cool dry gas delivered at room temperature (21 degrees C) with 0% relative humidity. Various delivery methods are available for humidifying and heating CO2 gas. This study was designed to determine the effects of heating and humidifying gas for the intraabdominal environment. METHODS: For this study, 44 patients undergoing laparoscopic Roux-en-Y gastric bypass were randomly assigned to one of four arms in a prospective, randomized, single-blinded fashion: raw CO2 (group 1), heated CO2 (group 2), humidified CO2 (group 3), and heated and humidified CO2 (group 4). A commercially available CO2 heater-humidifier was used. Core temperatures, intraabdominal humidity, perioperative data, and postoperative outcomes were monitored. Peritoneal biopsies were taken in each group at the beginning and end of the case. Biopsies were subjected staining protocols designed to identify structural damage and macrophage activity. Postoperative narcotic use, pain scale scores, recovery room time, and length of hospital stay were recorded. One-way analysis of variance (ANOVA) and the nonparametric Kruskal-Wallis test were used to compare the groups. RESULTS: Demographics, volume of CO2 used, intraabdominal humidity, bladder temperatures, lens fogging, and operative times were not significantly different between the groups. Core temperatures were stable, and intraabdominal humidity measurements approached 100% for all the patients over the entire procedure. Total narcotic dosage and pain scale scores were not statistically different. Recovery room times and length of hospital stay were similar in all the groups. Only one biopsy in the heated-humidified group showed an increase in macrophage activity. CONCLUSIONS: The intraabdominal environment in terms of temperature and humidity was similar in all the groups. There was no significant difference in the intraoperative body temperatures or the postoperative variable measured. No histologic changes were identified. Heating or humidifying of CO2 is not justified for patients undergoing laparoscopic bariatric surgery.

Differences in the adsorption behaviour of poly(ethylene oxide) copolymers onto model polystyrene nanoparticles assessed by isothermal titration microcalorimetry correspond to the biological differences.

The adsorption behaviour of a tetrafunctional copolymer of poly (ethylene oxide)-poly (propylene oxide) ethylene diamine (commercially available as Poloxamine 908) and a diblock copolymer of poly (lactic acid)-poly (ethylene oxide) (PLA/PEG 2:5) onto a model colloidal drug carrier (156 nm sized polystyrene latex) is described. The adsorption isotherm, hydrodynamic thickness of the adsorbed layers and enthalpy of the adsorption were assessed. The close similarity in the conformation of the poly (ethylene oxide) (PEO) chains (molecular weight 5,000 Da) in the adsorbed layers of these two copolymers was demonstrated by combining the adsorption data with the adsorbed layer thickness data. In contrast, the results from isothermal titration microcalorimetry indicated a distinct difference in the interaction of the copolymers with the polystyrene colloid surface. Poloxamine 908 adsorption to polystyrene nanoparticles is dominated by an endothermic heat effect, whereas, PLA/PEG 2:5 adsorption is entirely an exothermic process. This difference in adsorption behaviour could provide an explanation for differences in the biodistribution of Poloxamine 908 and PLA/PEG 2:5 coated polystyrene nanoparticles observed in previous studies. A comparison with the interaction enthalpy for several other PEO-containing copolymers onto the same polystyrene colloid was made. The results demonstrate the importance of the nature of the anchoring moiety on the interaction of the adsorbing copolymer with the colloid surface. An endothermic contribution is found when an adsorbing molecule contains a poly (propylene oxide) (PPO) moiety (e.g. Poloxamine 908), whilst the adsorption is exothermic (i.e. enthalpy driven) for PEO copolymers with polylactide (PLA/PEG 2:5) or alkyl moieties.

Nasal congestion: mechanisms, measurement and medications. Core information for the clinician.

The article provides the clinician with core information about the aetiology and treatment of nasal congestion and discusses nasal blood vessels, autonomic nerves, nasal cycle, effects of posture, subjective sensation of congestion, objective assessments of congestion and medical and surgical treatments.

Bluetongue virus does not persist in naturally infected cattle.

Studies were designed to test if observations by Takamatsu et al. in 2003 were applicable to natural infection of cattle with bluetongue virus (BTV). These observations suggested that ovine gamma delta T-cells could become persistently infected and subsequent midge feeding could induce virus replication. Skin biopsies and blood were collected from 28 cattle naturally infected with BTV-1. Blood samples were processed for virus isolation by embryonated chicken egg inoculation and for serology by BTV competitive enzyme-linked immunosorbent assay and BTV-1 virus neutralisation. BTV-1 was isolated from the blood of all animals and serology confirmed infection with BTV-1. A total of 288 skin biopsies were collected and cultured in the presence of interleukin 2 and epidermal growth factor. Sampling commenced as soon as either serology or virus isolation indicated infection with BTV and continued at weekly intervals for at least eight weeks then monthly for another two months. The natural viraemias in this experiment ranged from one to five weeks. BTV-1 was isolated from only one skin biopsy sample. This sample was collected during the week in which the animal was viraemic. These findings provide compelling evidence that BTV does not persist in gamma delta T-cells in the skin of naturally infected cattle.

The effect of blood sampling site and physicochemical characteristics of drugs on bioavailability after nasal administration in the sheep model.

PURPOSE: Investigate the effect of blood sampling site and physicochemical characteristics of drugs on the pharmacokinetic (PK) parameters obtained after intravenous and nasal administration in sheep and compare results with computer simulations. METHODS: Three drugs, insulin, morphine, and nicotine, were administered nasally and by intravenous (IV) injection to sheep, and serial blood samples collected concurrently from the carotid artery (insulin, morphine) or cephalic vein (nicotine) and jugular vein. Plasma drug concentrations were measured, and pharmacokinetic and statistical analyses performed, to evaluate sampling site differences. RESULTS: After nasal insulin, bioavailabilities calculated from the two blood sampling site data were comparable. In contrast, apparent bioavailabilities following nasal morphine or nicotine were significantly higher when sampling was from the jugular vein. These results were supported by computer simulations. These observations are attributed to the greater effects of noninstantaneous mixing of drugs for jugular vein sampling following nasal dosing, compared to the other sampling sites, which is significant for drugs that are rapidly and well absorbed and that have a high volume of distribution (Vd). CONCLUSION: The results clearly show that the characteristics of the drug and the blood sampling site can have a significant effect on the pharmacokinetic results obtained after nasal administration in sheep.

Nasal delivery of chitosan-DNA plasmid expressing epitopes of respiratory syncytial virus (RSV) induces protective CTL responses in BALB/c mice.

Respiratory syncytial virus (RSV), an important pathogen of the lower respiratory tract, is responsible for severe illness both in new born and young children and in elderly people. Due to complications associated with the use of the early developed vaccines, there is still a need for an effective vaccine against RSV. Most pathogens enter the body via mucosal surfaces and therefore vaccine delivery via routes such as the nasal, may well prove to be superior in inducing protective immune responses against respiratory viruses, since both local and systemic immunity can be induced by nasal immunisation. Previously we have shown that intradermal immunisation of a plasmid DNA encoding the CTL epitope from the M2 protein of RSV induced protective CTL responses. In the present study, the mucosal delivery of plasmid DNA formulated with chitosan has been investigated. Chitosan is a polysachharide consisting of copolymers of N-acetylglucosamine and glucosamine that is derived from chitin, a material found in the shells of crustacea. Intranasal immunisation with plasmid DNA formulated with chitosan induced peptide- and virus-specific CTL responses in BALB/c mice that were comparable to those induced via intradermal immunisation. Following RSV challenge of chitosan/DNA immunised mice, a significant reduction (P<0.001) in the virus load was observed in the lungs of immunised mice compared to that in the control group. These results indicate the potential of immunisation with chitosan-formulated epitope-based vaccines via the intranasal route.

Intranasal delivery of morphine.

Morphine administered nasally to humans as a simple solution is only absorbed to a limited degree, with a bioavailability of the order of 10% compared with intravenous administration. This article describes the development of novel nasal morphine formulations based on chitosan, which, in the sheep model, provide a highly increased absorption with a 5- to 6-fold increase in bioavailability over simple morphine solutions. The chitosan-morphine nasal formulations have been tested in healthy volunteers in comparison with a slow i.v. infusion (over 30 min) of morphine. The results show that the nasal formulation was rapidly absorbed with a T(max) of 15 min or less and a bioavailability of nearly 60%. The shape of the plasma profile for nasal delivery of the chitosan-morphine formulation was similar to the one obtained for the slow i.v. administration of morphine. Furthermore, the metabolite profile obtained after the nasal administration of the chitosan-morphine nasal formulation was essentially identical to the one obtained for morphine administered by the intravenous route. The levels of both morphine-6-glucuronide and morphine-3-glucuronide were only about 25% of that found after oral administration of morphine. It is concluded that a properly designed nasal morphine formulation (such as one with chitosan) can result in a non-injectable opioid product capable of offering patients rapid and efficient pain relief.

Development of a novel nasal nicotine formulation comprising an optimal pulsatile and sustained plasma nicotine profile for smoking cessation.

A novel nasal formulation, in the form of a nicotine-Amberlite resin complex powder has been developed that provided an optimal combined pulsatile and sustained plasma nicotine profile for smoking cessation. The adsorption isotherms of nicotine hydrogen tartrate salt on two types of Amberlite resins (IRP69 and IR120) were evaluated and the subsequent in vitro release properties of nicotine from the nicotine-Amberlite complex powders were tested using a Franz diffusion cell. Amberlite IRP69 and Amberlite IR120 are similar cationic exchange materials with the same ion-exchange capacity but due to a smaller particle size range (10-150 microm) Amberlite IRP69 had a better flow property and a better adsorptive capacity than Amberlite IR120. The material is used as an excipient in marketed pharmaceutical formulations. The highly water soluble salt, nicotine hydrogen tartrate, displayed good adsorption onto both types of Amberlite resin. The maximum adsorption of nicotine onto Amberlite IRP69 was 1.071 mg drug per mg resin. The cumulative release of drug from nicotine hydrogen tartrate-Amberlite complex powders showed that the higher the drug loading, the faster was the rate of release of the drug. Based on these results, various nicotine hydrogen tartrate-Amberlite IRP69 powder formulations containing different ratios of free to bound drug (50% to 100% bound) and a control solution were prepared and evaluated in a sheep model by nasal administration. The nicotine plasma profiles demonstrated that an initial rapid peak plasma level of nicotine followed by a sustained elevated level could be achieved by adjusting the ratio of free to bound nicotine in the Amberlite powder formulation. The curves obtained from some of the formulations were comparable to those predicted from a computer-generated pharmacokinetic model.

The release of diazepam from poly(hydroxybutyrate-hydroxyvalerate) microspheres.

Microspheres based on a poly(hydroxybutyrate-hydroxyvalerate) copolymer (PHBV) (Mw = 630kD, 21% mol HV) were loaded with diazepam using different emulsion-solvent evaporation processes. Gelatin was used as a strategy to alter the release profile of the incorporated drug. The mean diameter of microspheres was from 30-40 micron. Drug-release from the microspheres over a 30-day period showed a characteristic triphasic release pattern with an initial burst effect, but was linear over the same period and without a burst effect when gelatin was used as a coating agent. Scanning electron microscopy revealed that the microspheres had different structures depending upon their method of preparation.

[Preparation and characterization of prednisolone-poly (hydroxybutyrate-co-hydroxyvalerate) nanoparticles].

AIM: To optimize the preparation of sustained release prednisolone-poly (hydroxybutyrate-cohydroxyvalerate) (PNS-PHBV) nanospheres (NP) using the novel biodegradable materials PHBV as the carriers and PNS as a model drug. METHODS: PNS-PHBV nanospheres were prepared by ultrasonic-emulsion technique. The diameter, its distribution and Zeta potential on the surface of particles were measured by means of Zetasizer. RESULTS: The diameter of NP is in the range of 50-250 nm. The drug loading of NP increases but incorporation efficiency and Zeta potential dramatically decrease with increasing ratio of the feeding quantities of drug to those of carriers. The drug release behavior in vitro appeared to have biphasic characteristics with initial burst effect. The more burst effect, the less the diameters of nanoparticles. The longest release time was up to 32 h. CONCLUSION: The technology of preparation is reasonable and PNS-PHBV nanoparticle showed significant sustained release.

Transport of nanoparticles across the rat nasal mucosa.

The transport of 125I-radiolabelled latex nanoparticles across the nasal mucosa of rats was studied using a range of particle sizes and surface coatings. Translocation of the particles into the blood stream was examined by means of monitoring the radiolabel associated with the particles. Particles were detected in the blood after 5 minutes. The number of particles in the blood peaked at 60 minutes, and then remained constant for a further 2 hours. The smallest particles (20 nm) showed greater uptake than the largest particles investigated (1000 nm). The total maximum uptake seen for the smallest particles was in the order of 3.25% of administered dose. 100 nm particles coated with chitosan showed an increase in both the extent and rate of uptake, with the concentration in the blood peaking at 15 minutes rather than at 60 minutes. It is suggested that transport of the particles across the nasal membrane is due mainly to a transcellular transport mechanisms by the nasal associated lymphoid tissue (NALT), especially the M-cell like cells. However, some paracellular transport cannot totally be ruled out for the smallest particles, especially if coated with chitosan.