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PubMed2002

Comparison of the sensitivity of a 24 h-shell vial assay, and conventional tube culture, in the isolation of Herpes simplex virus - 1 from corneal scrapings.

BACKGROUND: Herpes simplex keratitis is a sight threatening ocular infection. A rapid and specific diagnosis is essential for the institution of specific antiviral therapy and to avoid complications that can arise from misdiagnosis and inappropriate treatment. Though a variety of techniques are available, isolation of Herpes simplex virus 1 (HSV-1) in culture provides the most reliable and specific method, and is considered as the gold standard in laboratory diagnosis of herpes simplex keratitis. We report a comparative study of the sensitivity of a 24 h-shell vial assay and conventional tube culture in the isolation of HSV-1 from corneal scrapings. METHODS: A total of 74 corneal scrapings obtained from 74 patients with a clinical suspicion of herpes simplex keratitis submitted for the isolation of HSV-1, were simultaneously inoculated into shell vial and tube cultures employing the vero cell line. Shell vial and tube cultures were terminated at 24 h and fifth day respectively. Isolation of HSV-1 was confirmed employing an indirect immunofluorescence assay. RESULTS: HSV-1 was isolated from 24/74 (32.4%) specimens employing both the methods. Sensitivity of both the techniques were found to be similar (20/24, 83.3%) (P = 1.0). CONCLUSION: A 24 h-shell vial assay is a rapid alternative technique in comparison to the time consuming conventional tube cultures for the isolation of HSV-1, especially from corneal scrapings for the laboratory diagnosis of herpes simplex keratitis.

Journal Article↗

PubMed2006

Ten years' experience of isolation of Rickettsia spp. from blood samples using the shell-vial cell culture assay.

Two strategies to improve the efficacy of the shell-vial method for Rickettsia were analyzed. Blood samples from 59 patients with Mediterranean spotted fever (MSF) were examined using the shell-vial technique. (i) DNA from positive lenses was obtained when they were contaminated. (ii) Blood sample from one patient was cultured in 17 shell-vials. R. conorii was identified in four cases by polymerase chain reaction (PCR)-RFLP. Three of these were obtained from cells adherent to lenses and the fourth one by using total patient blood sample. Rickettsia isolation using all blood samples as well as DNA from shell-vial lenses could be useful in the study of rickettsial infections.

Bacterial Typing Techniques↗

PubMed2002

Shell clamping behaviour in the limpet Cellana tramoserica.

The behaviour of clamping the shell against the substratum may play an important role in the limpet adhesion mechanism because friction generated by this behaviour resists dislodgement by shear forces. This paper describes the development of an apparatus to analyse limpet clamping activity in relation to known forces, including simulated wave activity and predator attack. The results show that Cellana tramoserica clamps its shell in a closely regulated manner consistent with an active role in the limpet adhesion mechanism. Limpets clamped sharply for several seconds in response to single disturbances such as tapping the shell. In response to more continuous disturbance simulating a concerted predator attack, limpets clamped tightly for several minutes. In response to lifting forces applied to the shell, limpets clamped at a set proportion of the lifting force, even if the lift force was a highly dynamic wave profile. This behaviour has implications for numerical models that attempt to describe limpet adhesion because it shows that limpets cannot be represented by a simple mechanical analogue and that the clamping behaviour must be accounted for if useful predictions are to be drawn.

Adaptation, Physiological↗

PubMed2001

The use of diagnostic radiology to detect shell irregularities in the New Zealand paua (abalone) Haliotis iris.

A method is described for the non-destructive, non-invasive, detection of shell lesions in the New Zealand paua, a marine gastropod Haliotis iris using diagnostic radiology. The X-ray method reliably detected the presence of shell lesions in 96% of the cases examined once lesion dimensions exceeded 6.2 x 7.1 mm. The extent of lesions above this size can be reliably and accurately determined from X-ray images viewed on a video display unit (VDU). Biofouling on the outside of the shell can cause misdiagnoses. This method is a significant animal welfare refinement in the identification of marine gastropods with shell lesions, when compared with traditional techniques which kill the animals.

Animals↗

PubMed1987

Antigens of powdered pearl-oyster shell causing hypersensitivity pneumonitis.

We describe the identification and characterization of antigens of the pearl-oyster shell which caused hypersensitivity pneumonitis in a 42-year-old worker. He was occupationally exposed to the dust of this shell in the manufacture of different ornaments. In addition to a typical history, the diagnosis was confirmed through a workplace-related exposure test and high titres of antigen-specific IgG antibodies. By means of the immunoblot technique, several relevant antigens could be detected in the shell of the pearl-oyster. Control sera also contained immunoglobulins that bound to some electrophoretically separated bands; these could represent antibodies that react with lectin-like components in the shell in a nonimmunologic manner.

Adult↗

PubMed2006

Brain reward regulated by AMPA receptor subunits in nucleus accumbens shell.

Drugs of abuse alter expression of AMPA-type glutamate receptor subunits (GluRs) in the nucleus accumbens (NAc), a key component of brain reward systems. The impact of this regulation on general motivational states is unclear. Here, we used herpes simplex virus vectors to examine how transient increases in the expression of GluR1 or GluR2 protein in the shell component of NAc affect the rewarding impact of electrical stimulation of the medial forebrain bundle, as reflected by intracranial self-stimulation (ICSS) thresholds in rats. We found that elevated GluR1 in NAc shell increases ICSS thresholds, an effect similar to that caused by treatments that cause anhedonia and dysphoria (prodepressive effects) in rats and humans (e.g., drug withdrawal, kappa-opioid agonists). In contrast, elevated GluR2 decreases ICSS thresholds, an effect similar to that caused by rewarding treatments (e.g., drugs of abuse). To confirm that viral vector-mediated elevations of GluR1 in the NAc shell produce molecular consequences that are different from those of elevated GluR2, we examined the expression of a set of drug-regulated genes 3 d after treatment using quantitative PCR. Elevated GluR1 was accompanied by sustained increases in the gene for GluR1, whereas elevated GluR2 was accompanied by decreases in prodynorphin. These data suggest that GluR1 and GluR2 in the NAc shell play opposing roles in the regulation of motivated behavior.

Analysis of Variance↗

PubMed2004

Diagnostic of Biomphalaria snails and Schistosoma mansoni: DNA obtained from traces of shell organic materials.

Freshwater snails belonging to the genus Biomphalaria act as intermediate hosts for the parasite trematode Schistosoma mansoni in Africa and in the neotropical region. Identification of such molluscs is carried out based on morphological characters and the presence of cercariae is verified through squeezing snails between two glass slides or by exposing them to artificial light. However, sometimes, the material collected includes molluscs with decomposed bodies or, yet, only empty shells, which precludes their identification and S. mansoni detection. Due to these difficulties, we have developed a methodology in which DNA may be extracted from traces of organic material from inside shells in order to identify molluscs through polymerase chain reaction and restriction fragment length polymorphism and to detect S. mansoni into these snails, by using low stringency polymerase chain reaction. Species-specific profiles obtained from B. glabrata, B. straminea, and B. tenagophila snails and their shells, maintained in laboratory for ten years, showed the same profiles. S. mansoni profiles showed to be present in shell specimens as far as the eighth week after being removed from aquarium.

Animals↗

PubMed2004

Photoabsorption study of Bacillus megaterium, DNA and related biological materials in the phosphorus K-shell edge region.

We measured the X-ray transmission spectra of several biologically related samples in the phosphorus K-shell edge absorption region. These include red phosphorus, hydrated sodium phosphate (Na(3)PO(4).12 H(2)O), deoxyribonucleic acid (DNA), adenosine triphosphate (ATP), diolylphosphatidyl choline (DOPC), and Bacillus megaterium spores. Red phosphorus essentially displays an edge-jump. All other spectra are similar in form and energy position: Each is dominated by a narrower, more intense first peak and a broader but less intense second peak. The corresponding K-shell edge absorption thresholds are shifted toward higher energy relative to that for red phosphorus, as expected for increasing degrees of phosphorus oxidation. The B. megaterium spectrum has aspects common to both the phosphate and DNA spectra and is therefore interpreted as a composite of spectra arising from DNA, ribonucleic acid (RNA) and phosphates within the spore. The B. megaterium spore spectrum provides information for resonant radiation damage studies in the phosphorus K-shell edge absorption region by identifying candidate photoexcitations. In addition, the absorption spectra will be useful in X-ray microscopy and macromolecular crystallography studies at the phosphorus K-shell edge.

Adenosine Triphosphate↗

PubMed1992

Adhesion between the resin shell and composite resin.

Adhesiveness between the resin shell and composite resin was examined. As the resin shell, SR-PE-ISOCETTE, made from thermosetting crown and bridge resin, was used. The shear bond strengths between the resin shell and photocurable composite resin bonded by various methods were measured after 1-day of immersion in water at 37 degrees C. Super-bond C & B treatment to the resin shell effectively improved the adhesiveness, giving a bond strength of about 14 MPa. Clearfil new bond, Clearfil porcelain bond, Unifast and MMA/TBBO treatment gave almost the same bond strengths of about 7-9 MPa. Silane coupling agents were not effective for improving the bond strength. It was revealed that 4-META was necessary for obtaining good adhesion between SR-PE-ISOCETTE and composite resin.

Boron Compounds↗

PubMed1997

Effects of YM-14673, a thyrotropin-releasing hormone analogue, injected into the shell and the core of the nucleus accumbens on production of repetitive jaw movements in rats: comparison with the effects of a dopamine D1 and D2 receptor agonist combination.

The present study examined whether the shell and the core of the nucleus accumbens play a differential role in the display of YM-14673-induced jaw movements in rats. For that purpose the effects of YM-14673 were compared to those of a SKF 82958 and quinpirole combination, a dopamine D1 and a D2 receptor agonist respectively, that is known to functionally differentiate these two subregions of the nucleus. Consistent with the previous report, bilateral injections of a mixture of SKF 82958 (5 micrograms) and quinpirole (10 micrograms) into the shell of the nucleus accumbens produced repetitive jaw movements, whereas similar injections of the mixture into the core did not induce such an effect. In contrast, there was no regional difference in the effects of YM-14673 on the production of repetitive jaw movements. Thus, both bilateral injections of YM-14673 (0.1 or 1.0 microgram) into the shell or the core produced similar repetitive jaw movements in a dose-related manner. Moreover, the pattern of oral movements induced by YM-14673 differed from that induced by the mixture of SKF 82958 and quinpirole; frequent tongue protrusions were evident in rats treated with the mixture but were not seen in YM-14673-treated rats. It therefore appears that, unlike the effects of the mixture of dopamine D1 and D2 receptor agonists, the effects of YM-14673 in the shell on the production of rat jaw movements do not differ from the effects of the compound in the core.

Animals↗

PubMed1985

Utilization by sheep of whole shelled corn impregnated with urea, calcium, potassium and sulfur.

Twenty-eight growing wether lambs (33.9 kg), adapted to urea for 40 d, were used in a metabolism study to determine if urea impregnation of corn could improve urea utilization. The following diets were compared: 1) whole shelled corn alone, 2) whole shelled corn impregnated with urea, calcium (Ca) as CaCl2, potassium (K) as KC2H3O2, and sulfur (S) as Na2S2O3 X 5H2O, 3) whole shelled corn fed with a dry supplement containing urea, Ca, K and S and 4) whole shelled corn fed with a dry supplement containing soybean meal, Ca and K. Additions were made to provide diets containing 12% crude protein, .37% Ca and .50% K. A 10:1 N (from urea) to S ratio, dry basis was used in urea-containing diets. Corn (90% dry matter) in diet 2 was impregnated by spraying 1.1 liters of an aqueous solution containing the above salts per 10 kg of corn dry matter. After mixing for 10 min in a horizontal mixer, the corn was dried in a laboratory grain drying bin with ambient laboratory air for 48 h. Lambs were fed 350 g of the respective diets plus 35 g orchardgrass hay twice daily during a 20-d metabolism trial. On the last day of the trial, ruminal fluid samples were collected at 0, 1, 2, 3, 4, 5 and 6 h postfeeding and jugular blood was obtained at 0 and 6 h postfeeding. Nitrogen-supplemented diets resulted in increased (P less than .01) absorption and retention of N. Digestibility of dry matter, organic matter and NFE tended to be greater in lambs fed impregnated corn than in lambs fed the other diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetates↗

PubMed1995

A comparison of trial shoe and shell shoe fitting techniques.

In Europe, bespoke orthopaedic shoes are usually sent for a trial fitting in order to check the fit and indicate any modifications required before final finishing. The use of shell shoes at the fit assessment stage, rather than the traditional alternative of partially or fully finished shoes, can offer service advantages, and is widely used for example in the Netherlands. However the comparability of shell fit assessment with the traditional method of trial shoe fit assessment has not been evaluated, either to assess its sensitivity or to elucidate any difference in assessment technique required of the orthotist. In this work, the results of fit assessments by both methods are compared. The trial involved a group of normal subjects wearing high street shoes of styles similar to those used for orthopaedic footwear. The results indicate that the shell fit assessments were in the main comparable to those for trial shoe fit. The only consistent area of deviation noted, in the heel at the topline, is attributable to a construction factor in shoe making. Apart from this area, the orthotist need not adjust his technique to make use of the shell method.

Anthropometry↗

PubMed2001

A histological study of shell disease syndrome in the edible crab Cancer pagurus.

Shell disease syndrome is characterised by the external manifestation of black spot lesions in the exoskeletons of crustaceans. In the present study, gills, hepatopancreas and hearts from healthy (<0.05% black spot coverage) and diseased (5 to 15% coverage) edible crabs, Cancer pagurus, were examined histologically to determine whether this disease can cause internal damage to such crabs. There was clear evidence of cuticular damage in the gills of diseased crabs leading to the formation of haemocyte plugs termed nodules. Nephrocytes found within the branchial septa of the gills showed an increase in the accumulation of dark material in their vacuoles in response to disease. In the hepatopancreas, various stages of tubular degradation were apparent that correlated with the severity of external disease. Similarly, there was a positive correlation between the number of viable bacteria in the haemolymph and the degree of shell disease severity. Approximately 21% of the haemolymph-isolated bacteria displayed chitinolytic activity. Overall, these findings suggest that shell disease syndrome should not be considered as a disease of the cuticle alone. Furthermore, it shows that in wild populations of crabs shell perforations may lead to limited septicaemia potentially resulting in damage of internal tissues. Whether such natural infections lead to significant fatalities in crabs is still uncertain.

Animals↗

PubMed2002

Dynamics of shell disease in the edible crab Cancer pagurus: a comparative study between two sites on the Gower Peninsula, South Wales, UK.

Shell disease syndrome is a degradative condition of the crustacean exoskeleton which results in the formation of black-spot lesions. Field surveys on the edible crab Cancer pagurus (L.) population at 2 sites in the Gower Peninsula of South Wales, UK, namely Langland Bay and Rhossili causeway, revealed similarities in the prevalence of shell disease but differences in the severity. Male crabs from Langland Bay displayed significantly greater severities of the disease on the dorsal carapace and ventral surfaces than those in Rhossili. The greatest severities of the disease in Langland were attributable to sand abrasion injuries during back-burrowing behaviour and prolonged exposure to high numbers of chitinolytic bacteria. Lower severities of shell disease in males from Rhossili were a reflection of the inability to back-burrow due to the nature of the onshore sediment, and hence the crabs were only exposed to low levels of chitinolytic bacteria in the water column. On areas of the causeway that permitted back-burrowing, the chitinase enzyme activities in sediments were significantly lower than those in Langland Bay. It is concluded that the potential for crustacean shell degradation is higher at Langland than Rhossili, but whether the differences in chitinolytic abilities of the sediments at the 2 sites are a result of differences in pollution levels or simply of different substratum types, remains to be determined.

Animals↗

PubMed2005

Unchanged prevalence of shell disease in the edible crab Cancer pagurus four years after decommissioning of a sewage outfall at Langland Bay, UK.

Shell disease is a bacteria-associated degradative disease of the crustacean exoskeleton that leads to formation of extensive lesions in the cuticle with ultimate involvement of haemocoelic septicaemia. Field surveys of edible crabs Cancer pagurus from Langland Bay, Gower, UK, from February 1997 to March 1998 had revealed unusually high prevalence (ca. 55%) of this disease amongst the population, and it was suggested that one of the predisposing factors might have been the presence of raw sewage in this area. Since February 1999, a local raw sewage outfall affecting this area has been decommissioned, raising the possibility that the prevalence and severity of this disease could have become reduced as a result of the cessation of sewage exposure. Therefore, the aim of this study was to compare the prevalence and severity of shell disease in edible crabs from Langland Bay pre- and post-sewage discharge. The overall prevalence of shell disease from February 2003 to March 2004 was 59.2%, and in only 1 size class (80-99 mm carapace width, males) was the prevalence higher in 2003-04 than in 1997-98. In terms of severity, only smaller crabs (60-199 mm width) showed a significant reduction in 2003-04 compared with 1997-98. No changes were found in the severity of the disease in different regions of the exoskeleton of infected crabs between the 1997-98 survey and the present work. Overall, it is concluded that no significant changes in the occurrence of shell disease have resulted from the improvement in water quality (in terms of faecal pollution) at this site, suggesting that sewage pollution is probably not a major contributory factor to this disease.

Animals↗

PubMed2006

Shell disease: abnormal conchiolin deposit in the abalone Haliotis tuberculata.

Shell disease in the abalone Haliotis tuberculata L. is characterized by a conchiolin deposit on the inner surface of the shell. The gross clinical signs appear similar to the Brown Ring Disease (BRD) of clams. BRD has been extensively described in clams and is known to be responsible for severe mortalities and the collapse of the clam aquaculture industry in western France. In the clam, it was found to be caused by the infection of the mantle by Vibrio tapetis. Brown protein deposits have been observed in various abalone species around the world; some of these have been associated with a fungal infection in New Zealand, but the ones described here are similar to bacterial infections observed in clams. Larger animals appeared to be more affected by the disease, and a positive correlation of the number of successive infections found in the shells with the level of infestation of the shell by borers suggests that boring polychaetes and sponges may be vectors of the disease, or that the parasite infestation may increase the susceptibility of the animal to this infection. There is no evidence, however, that this infection causes mortality in abalone.

Animals↗

PubMed1980

Effect of estradiol on calcium and calcium binding in serum of thick and then-shell lines of chickens.

Estradiol (10 mg/bird) was injected intramuscularly into hens of a thick-shell line and a thin-shell line as well as into roosters of both lines on day 0. Serum levels of calcium (Ca), phosphorus (P), and Ca binding involving the proteins vitellogenin (a phosphoprotein) and albumin were measured on day 0 and day 6 or 7. Serum levels of all measured Ca and P parameters and vitellogenin binding of both sexes were significantly greater, while levels of albumin binding were significantly less on day 6 or 7 than on day 0. Serum levels of non-diffusible Ca in hens and vitellogenin binding in both sexes were significantly greater in the thick-shell than in the thin-shell line. There were no significant differences between lines for total serum P of either sex. A study of the hens only revealed that the change in nondiffusible Ca and vitellogenin binding from day 0 to day 6 or 7 was significantly different between lines. The correlations between vitellogenin binding and total P, expressed as either change or percent change, were greater than .8.

Animals↗

PubMed1984

Toxicity of jimson weed seed and cocoa shell meal to broilers.

Jimson weed seed meal, which contains alkaloids toxic to animals, and cocoa shell meal, which contains theobromine, also toxic to animals, were used in two experiments with broilers to determine relative toxicity. Pure theobromine was added to diets to furnish the same levels as furnished by 1, 2, 4, and 6% dietary cocoa shell meal, which contained, by analysis, 1.3% theobromine. Approximately 1% jimson meal is the upper dietary limit that can be safely incorporated into the diet of young broilers. Dietary levels of 3 and 6% from 1 to 21 days of age drastically depressed performance. Cocoa shell meal that contained 1.3% theobromine was somewhat less toxic to chicks than jimson meal. However, performance tended to be depressed with dietary levels above 1%. Pure theobromine was a little more toxic than that furnished by cocoa shell meal.

Alkaloids↗