Drain-free neck dissection: the use of Artiss fibrin sealant.

OBJECTIVE: To study the safety and efficacy of Artiss fibrin sealant in lateral neck dissection, focusing on drain retention time, length of hospital stay and post-operative complications. METHODS: A retrospective review was conducted of patients who underwent neck dissection in a UK hospital over a 12-month period. RESULTS: Twenty-three patients were identified; 13 patients had Artiss and a drain, 10 patients had Artiss only. All drains were removed by post-operative day 2. No post-operative fluid collections or complications were recorded. Patients who had Artiss only without a drain were discharged on post-operative day 1. CONCLUSION: The use of Artiss reduced the drain retention time and hospital stay, with no post-operative complications. Neck dissection can be safely undertaken with no drain, and can potentially be carried out as a day-case procedure, with the application of Artiss. These findings benefit patients and the National Health Service by improving the patient journey and reducing overall costs.

Influence of process parameters in electrical discharge machining on H13 die steel.

H13 die steel is characterized by its high hardness and need for special surface features that are obtained by nontraditional machining processes. Electrical discharge machining (EDM) is used to machine hard materials and to produce complicated shapes. In this work, different EDM process parameters are investigated on H13 die steel. Several experiments are conducted to study the effect of three process parameters: peak current (Ip), pulse on-time (Ton) and electrode material on the machining process of H13 die steel. The machining process is evaluated by material removal rate (MRR), electrode wear ratio (EWR%) and surface roughness (SR) as indicators of the process efficiency in terms of quality and cost. Taguchi method was used to investigate the significant effect of process parameters on the performance measurements and the optimal parameters of the EDM process. For analysis and explanations Minitab version 17 software was used. Different process parameters were experimentally investigated and statistically analyzed and the results showed that the copper electrode leads to the highest MRR and lowest EWR%; whereas the brass electrode leads to the lowest SR.

Cell culture-derived HCV cannot infect synovial fibroblasts.

Worldwide 170 million individuals are infected with hepatitis C virus (HCV), up to 45 million of whom are affected by arthropathy. It is unclear whether this is due to viral infection of synovial cells or immune-mediated mechanisms. We tested the capacity of primary synovial fibroblasts to support HCV propagation. Out of the four critical HCV receptors, only CD81 was expressed to any significant extent in OASF and RASF. Consistent with this, pseudotyped HCV particles were unable to infect these cells. Permissiveness for HCV replication was investigated by transfecting cells with a subgenomic replicon of HCV encoding a luciferase reporter. OASF and RASF did not support replication of HCV, possibly due to low expression levels of miR-122. In conclusion, primary human synovial fibroblasts are unable to support propagation of HCV in vitro. HCV-related arthropathy is unlikely due to direct infection of these cells.

Eosinophilic oesophagitis: a systematic review for otolaryngologists.

BACKGROUND: Eosinophilic oesophagitis is a chronic, immune/antigen-mediated oesophageal disease, only recently, but increasingly, recognised in the world literature. It is diagnosed and managed primarily by medical gastroenterologists and allergy specialists, and is a distinct disease entity, affecting both children and adults. Few studies have been published in otolaryngology journals, although otolaryngologists will encounter patients with undiagnosed eosinophilic oesophagitis. Patients may present with dysphagia, bolus obstruction or with other ENT disorders, such as atopic rhinitis, reflecting the underlying systemic allergic disorder. OBJECTIVE: This paper systematically reviews the evidence base published on the epidemiology, clinical presentation, diagnosis, treatment and prognosis of eosinophilic oesophagitis, particularly as it relates to otolaryngology practice.

Morpho-Physiological and Biochemical Criteria of Acanthamoeba spp. Isolated from the Egyptian Aquatic Environment.

BACKGROUND: The free-living amoebae Acanthamoeba spp., have been recognized as etiologic agents of amoebic encephalitis, keratitis, otitis, lung lesions and other skin infections mainly in immuno-compromised individuals. In this study, morpho-physiological and biochemical characterization of Acanthamoeba strains isolated from the Egyptian aquatic environment were surveyed. METHODS: Some Acanthamoeba species were cultivated on non-nutrient agar. Isolated strains of Acanthamoeba were identification based on the morphology of trophic and cyst forms in addition to temperature and osmo-tolerance assays. Biochemical characterization of the isolated amoeba strains was performed using quantitative assay as well as qualitative determination of proteolytic activity in zymograph analysis. RESULTS: Potentially pathogenic Acanthamoeba species were isolated from all of the examined water sources. Colorimetric assays showed protease activity in the heat-tolerant isolates of Acanthamoeba. All pathogenic isolates of Acanthamoeba exhibited higher protease activity than did the non-pathogenic ones. The zymographic protease assays showed various banding patterns for different strains of Acanthamoeba. CONCLUSION: The incidence and prevalence of the pathogenic Acanthamoeba species in the aquatic environment using parasitological and biochemical diagnostic tools will provide baseline data against which the risk factors associated with waterborne transmission can be identified.

Cross-reaction of antigen preparations from adult and larval stages of the parasite Setaria equina with sera from infected humans with Wuchereria bancrofti.

Crude antigenic preparations from Setaria equina were used in ELISA and Western blotting to examine cross-reaction with human sera from areas endemic for bancroftian filariasis. Sera from normal subjects from non-endemic areas were included as negative controls. Cross-reaction was found between S. equina antigens and antibodies in the sera of Wuchereria bancrofti-infected patients, with the highest levels observed between sera of chronic infected patients and Setaria spp. crude female worm surface antigen (CFSWA). In the absence of active transmission of Setaria spp. infection, CFWSA is useful to detect chronic W. bancrofti infection before patients become symptomatic, particularly when chronic patients are known to be amicrofilaraemic. In the presence of active S. equina infection, antigens from the adult and microfilaraemic stages showed the highest degree of cross-reaction with human sera.

Cross-reaction of antigen preparations from adult and larval stages of the parasite Setaria equina with sera from infected humans with Wuchereria bancrofti

Crude antigenic preparations from Setaria equina were used in ELISA and Western blotting to examine cross-reaction with human sera from areas endemic for bancroftian filariasis. Sera from normal subjects from non-endemic areas were included as negative controls. Cross-reaction was found between 5. equina antigens and antibodies in the sera of Wuchereria bancrofti-infected patients, with the highest levels observed between sera of chronic infected patients and Setaria spp. crude female worm surface antigen [CFSWA]. In the absence of active transmission of Setaria spp. infection, CFWSA is useful to detect chronic W. bancrofti infection before patients become symptomatic, particularly when chronic patients are known to be amicrofilaraemic. In the presence of active 5. equina infection, antigens from the adult and microfilaraemic stages showed the highest degree of cross-reaction with human sera

Setaria equina: in vivo effect of diethylcarbamazine citrate on microfilariae in albino rats.

Although diethylcarbamazine citrate (DEC) is successful drug in eliminating human filariasis, yet, its mode of action is still debatable. Herein, the effect of DEC to treat albino rats infected with the animal filarial parasite Setaria equina was tested. Microfilarial (mf) counts and sections from liver, lung, kidney as well as spleen were investigated at different time points after treatment by light microscopy. After 45 and 300min of treatment, a significant decrease in blood mf was observed accompanied by adherence of degenerated mf to both kupffer cells and leukocyte in liver sections. In lung sections, loss of sheath was observed at 45min, while degeneration was observed at later time points. In kidney sections, more mf counts and less matrix were observed in the glomeruli at all time points after treatment. Degenerated mf were observed in spleen sections only at, late time point, 480min after treatment. In conclusion, one of the possible mechanisms by which DEC reduces blood microfilarial count is trapping larvae in organs and killing them through cellular adherence.

Characterization of an avian influenza virus H5N1 Egyptian isolate.

The highly pathogenic influenza virus H5N1 that infected chickens in Egypt in 2006 was characterized at immunologic and molecular levels. Cloacal swabs from chicken were analyzed by rapid antigen detection and RT-PCR using H5- and N1-specific primers, which confirmed the presence of an H5N1 influenza virus in infected chickens. Sequencing results revealed 100% homology of both genes with previously published sequences of H5N1 isolates from Egypt and the Middle East. The virus was isolated and propagated in MDBK cells in culture. Host cells showed a substantial cytopathic effect within 2 days of infection, which increased dramatically by the fourth day. Plaque infectivity titers of virus harvested from cell culture were initially 10(5)PFUs/ml and increased to 10(8)PFUs/ml after two additional passages and ultrafiltration. Formaldehyde treatment completely inactivated the virus, and MDBK cells inoculated with the killed virus showed no cytopathic effect. Two days after chickens were immunized with the killed virus, their sera showed that the killed Egyptian isolate was highly immunogenic. Western blot analysis showed that sera had antibodies reacting to four viral peptides: hemagglutinin (61.5kDa), RNA-binding protein (56kDa), neuraminidase (50kDa), and 45-kDa protein. In a challenge infection, the vaccine protected immunized chickens from death and reduced viral shedding.

Novel growth of aluminium nitride nanowires.

This work describes novel growth of aluminium nitride (AIN) nanowires by nitridation of a mixture consists of aluminium and ammonium chloride powders (Al:NH4Cl = 1.5:1 weight ratio) at 1000 degrees C for 1 h in flowing nitrogen gas (1 l/min). XRD analysis of the product showed the formation of pure hexagonal AIN. SEM micrographs of as-synthesized product revealed the growth of homogeneous AIN nanowires (phi 40-150 nm). No droplets were observed at the tips of obtained nanowires which suggests that they were grown mainly by a vapor-phase reactions mechanism. Thermodynamic analysis of possible intermediate reactions in the operating temperatures range illustrates that these nanowires could be grown via spontaneous vapor-phase chlorination-nitridation sequences.

Enzyme-linked immunosorbent assay with worm vomit and cercarial secretions of Schistosoma mansoni to detect infections in an endemic focus of Burkina Faso.

Cercariae and adult Schistosoma mansoni were used to prepare, respectively, cercarial secretions (CS) and worm vomit (WoV). These were used as antigens in an enzyme-linked immunosorbent assay (ELISA) to test the IgG-reactivity of sera obtained in an S. mansoni-endemic area of Burkina Faso. Among the egg-excreting individuals (n = 240), 94.6% reacted positively with WoV, but only 62.9% with CS, thus suggesting a high diagnostic sensitivity of WoV, but not of CS. Among those individuals without detectable eggs in two Kato-Katz thick smears from different stool specimens (n = 215), the respective percentages of positive IgG reactivity were 78.1% and 63.3%. These positive reactions in the absence of detectable eggs are interpreted in terms of limited sensitivity of parasitological stool examinations. Optical density values in ELISA with CS, but not with WoV, correlated negatively with age, which may reflect decreasing exposure to cercariae in older individuals.

Detection of inducible nitric oxide synthase in Schistosoma japonicum and S. mansoni.

Schistosoma japonicum and S. mansoni were tested for reactivity with an anti-inducible nitric oxide (iNOS) antibody and the distribution of iNOS was studied by immunofluorescent tests in different stages of the parasites. Reactivity was associated with the tegument in both larval schistosomes (sporocysts and cercariae) and eggs. With adult worms, the majority of the immunofluorescence was predominantly subtegumental in S. japonicum and parenchymal in S. mansoni. Fluorescence was also observed in host tissues (snails and mouse liver). In Western blots, the enzyme of S. japonicum had an apparent molecular weight of about 210 kDa. The possible role of worm and host iNOS in the parasite-host interrelation remains to be clarified.

Serine protease and phenoloxidase activities in hemocytes of Biomphalaria glabrata snails with varying susceptibility to infection with the parasite Schistosoma mansoni.

The snail Biomphalaria glabrata possesses hemocytes, which are supposed to interact with the larval stages of the human parasite Schistosoma mansoni. We describe trypsin-like serine protease(s) and phenoloxidase activities in lysates from these hemocytes. Both enzymes have activity optima around pH 9.5. The serine protease was inhibited by EDTA, PMSF, antipain and aprotinin, and the phenoloxidase activity by diethydithiocarbamate. By comparison, the serine protease activity in secretions of S. mansoni cercariae also had an alkaline pH optimum around 10.5 and was sensitive to the same inhibitors. In addition, serine protease activities from snails and cercariae had the same molecular mass of 28 kDa. However, the K(m) value of the serine protease(s) and the K(i) values of different inhibitors were generally lower for the snail enzyme than for the cercarial enzyme. The serine protease activity varied among individual snails but activity in hemocyte lysates and hemolymph correlated strongly. There was no detectable difference in the levels of activity between snails which are susceptible or resistant to schistosome infection.

Biochemical comparison of the serine protease (elastase) activities in cercarial secretions from Trichobilharzia ocellata and Schistosoma mansoni.

We report on serine protease activity in cercarial secretions (CSs) from the bird parasite Trichobilharzia ocellata. Using a colorigenic substrate, the biochemical properties of this enzyme were studied and its activity was compared to the homologous one in CSs from the human parasite Schistosoma mansoni. The specific serine protease activity was always 2- to 3-fold higher in CSs from T. ocellatacompared to S. mansoni. The enzyme has its optimal activity at pH 10.5, is Ca2+-dependent (inhibition with EDTA) and has a trypsin-like (inhibition with anti-pain) serine proteinase activity (inhibition with PMSF and aprotinin). The K(m) value of the serine protease from T. ocellatawas higher than that of S. mansoni, and the K(i) values for several inhibitors were generally lower for the enzyme of T. ocellatathan that of S. mansoni except for EDTA. The enzyme activities from both parasites had a molecular weight of 30 kDa in gelatin-SDS-polyacrylamide gels. The intensity of the gelatin digestion bands was stronger with the T. ocellata than with the S. mansoni enzyme.

Species-restricted antibody response against a DNA-construct coding for aspartic proteinase from Schistosoma japonicum.

DNA-based vaccine technology was used to immunize against the schistosome digestive enzyme, cathepsin D aspartic proteinase. The cDNA coding for Schistosomajaponicum aspartic proteinase was cloned in a mammalian expression vector under control of the CMV promoter/enhancer and expressed for the first time in transfected mammalian cells as well as in mice immunized--by means of intra-ear pinna injection--with the aspartic proteinase-encoding DNA construct. Mice developed antibodies which recognized the native protein in homogenates of S. japonicum worms and reacted with the gut and, to a much lesser degree, with the parenchyma of the parasites in cryostat sections. It was noteworthy that the vaccinated mouse sera did not detectably cross-react with S. mansoni antigens either in homogenates or on cryostat sections. By contrast, infection sera of mice or humans strongly cross-reacted with both schistosome species. We conclude that DNA vaccination can induce species-restricted antibody responses against schistosome proteins. The implications of this previously unrecognized specificity are discussed.

Antibodies induced in mice by a DNA-construct coding for the elastase of Schistosoma mansoni recognize the enzyme in secretions and preacetabular glands of cercariae.

A DNA-construct coding for the elastase of the parasite Schistosoma mansoni was prepared from adult S. mansoni worm RNA which was reverse transcribed into cDNA. The gene coding for the elastase was amplified using primers specific for the sequence of cercarial elastase and was cloned into a mammalian expression vector. Expression of the elastase gene at the transcriptional level was achieved for the first time in transfected mammalian cells (COS-7) and was also successful in muscle tissue of mice injected with the DNA-construct. These mice developed antibodies recognizing in Western blots the elastase from cercarial secretions. Also, these antibodies reacted in immunofluorescence tests with the preacetabular glands of cercariae, i.e. the site of origin for elastase. Thus, the DNA-construct induced the expression of elastase in mice and formation of antibodies that recognized the native antigen.

Infection induces antibodies against the cercarial secretions, but not against the cercarial elastases of Schistosoma mansoni, Schistosoma haematobium, Schistosoma japonicum and Trichobilharzia ocellata.

Cercarial secretions from different species of the parasite Schistosoma and from Trichobilharzia ocellata contain a proteolytic activity, cercarial elastase, which was demonstrated by a 30 kDa band in gelatin gels. Sera of patients infected with Schistosoma mansoni, Schistosoma haematobium or Schistosoma japonicum contain immunoglobulin G which react in ELISA with cercarial secretions from all schistosomes and cross-react among the different parasite species. In Western blots, however, infection sera from patients, as well as heavily infected mice or rabbits, did not react with a 30-kDa protein. Moreover, when sections from infected snails (Biomphalaria, Bulinus and Lymnaea) were analysed by immunofluorescence using the same infection sera, only the tegument of the developing cercariae was recognized, but not the acetabular glands. In contrast, when antisera against purified cercarial elastase from either S. mansoni or S. haematobium were tested with sections of infected Biomphalaria or Bulinus, fluorescence was strong in the preacetabular glands of the cercariae of either species, but undetectable with the tegument. Cross-reactivity of both antisera extended to T. ocellata-infected Lymnaea, but not to S. japonicum-infected Oncomelania. In conclusion, although immunization with purified cercarial elastase results in antibody production, the enzyme does not induce an apparent antibody response following natural infection.

DNA vaccination with asparaginyl endopeptidase (Sm32) from the parasite Schistosoma mansoni: anti-fecundity effect induced in mice.

DNA-based vaccine technology was used to induce an immune response in mice against a schistosome cysteine proteinase, asparaginyl endopeptidase (Sm32). The cDNA coding for Sm32 was cloned in a mammalian expression vector under control of the CMV promoter/enhancer and expressed for the first time in transfected mammalian cells as well as in mice immunized with the Sm32-encoding DNA construct. These mice developed antibodies which recognized the native protein not only in homogenates of Schistosoma mansoni worms but also in the gut on cryostat sections of the parasites. This DNA vaccine led to an anti-fecundity effect: female worms of a challenge infection produced 37% less eggs than those growing in naïve mice. The results suggest that Sm32 may be a candidate antigen for the generation of an anti-pathology vaccine against schistosomes.

Circulating filarial antigens for monitoring the efficacy of ivermectin in treatment of filariasis.

Seventy-three asymptomatic bancroftian filariasis patients with positive microfilaria in their blood films were included. The patients were randomly divided into 2 groups: ivermectin group (50 cases) given 2 doses each of 100 ug/kg body weight, 3 months apart, and 23 cases had 2 doses of placebo. The study was run blindly for one year. The initial mean microfilaria (MF) count was 111/ml. At 3 months after ivermectin therapy, mean MF became 7.8/ml and 24% of ivermectin treated cases had no detectable MF (P <0.05). At 6, 9 and 12 months, the mean MF count became 4.1, 6.5 and 11/ml with amicrofilaria in 54%, 42% and 40% of treated cases respectively (P <0.05). On the other hand, no statistically significant change in the mean MF count in placebo group was detected. The routine laboratory investigations were unchanged or slightly improved at 3 and 6 months. Side effects after the first dose of ivermectin were mild fever in 16% and weakness in 20%. None was recorded after the second dose. Circulating filarial antigens could be detected in 66% of cases before treatment, as all cases with high microfilaremia had positive antigenemia. The mean antigen level started to decline significantly after 9 months post treatment. At the end of the study (one-year), all negative microfilaremic cases had negative antigen levels, indicating that detection of antigen in-patients sera is a very good indicator of cure and efficacy of the drug.

Blockage of skin invasion by schistosome cercariae by serine protease inhibitors.

Invasion of skin by schistosome cercariae is facilitated by a serine protease secreted from the acetabular cells of cercariae in response to skin lipid. Specific inhibitors of the protease, when applied to human skin in formulations designed to retain the inhibitor on and in the upper stratum corneum layers, block cercarial invasion of human skin. Both peptide-based, irreversible inhibitors and non-peptide, reversible inhibitors block cercarial invasion when applied in a propylene glycol:isopropyl alcohol (3:1) formulation in vitro. Arrest of cercarial invasion could be achieved even after immersion of treated skin in water for 2 hr. Peptide-based irreversible inhibitors in the presence of three different Topicare Delivery Compounds optimized arrest of cercarial invasion. The three Topicare Delivery Compounds applied alone prevented 80-100% of cercarial invasion. With inclusion of the inhibitor, there was 97-100% inhibition in vitro. The optimal formulation with inhibitor was then applied to the tails of BALB/c mice, and the mice were exposed to 120 cercariae by tail immersion. With the carrier lotion alone, there was a 50% reduction in worm burden and a 70% reduction in egg burden. When inhibitor was included, an 80% reduction in worm burden and a 92% reduction in egg burden was observed.