PubMed Health⌕ Search

Biomedical subjects

M Rothschild

Publications and source records attributed to M Rothschild.

At least 19 recordsLinked to original sources

Development of polymorphic expressed sequence tag-derived microsatellites for the extension of the genetic linkage map of the black tiger shrimp (Penaeus monodon).

In this study, microsatellite markers were developed for the genetic linkage mapping and breeding program of the black tiger shrimp Penaeus monodon. A total of 997 unique microsatellite-containing expressed sequence tags (ESTs) were identified from 10 100 EST sequences in the P. monodon EST database. AT-rich microsatellite types were predominant in the EST sequences. Homology searching by the blastn and blastx programs revealed that these 997 ESTs represented 8.6% known gene products, 27.8% hypothetical proteins and 63.6% unknown gene products. Characterization of 50 markers on a panel of 35-48 unrelated shrimp indicated an average number of alleles of 12.6 and an average polymorphic information content of 0.723. These EST microsatellite markers along with 208 other markers (185 amplified fragment length polymorphisms, one exon-primed intron-crossing, six single strand conformation polymorphisms, one single nucleotide polymorphism, 13 non-EST-associated microsatellites and two EST-associated microsatellites) were analysed across the international P. monodon mapping family. A total of 144 new markers were added to the P. monodon maps, including 36 of the microsatellite-containing ESTs. The current P. monodon male and female linkage maps have 47 and 36 linkage groups respectively with coverage across half the P. monodon genome.

Animals↗

Evidence for new alleles in the protein kinase adenosine monophosphate-activated gamma(3)-subunit gene associated with low glycogen content in pig skeletal muscle and improved meat quality.

Several quantitative trait loci (QTL) affecting muscle glycogen content and related traits were mapped to pig chromosome 15 using a three-generation intercross between Berkshire x Yorkshire pigs. On the basis of the QTL location the PRKAG3 (protein kinase, AMP-activated, gamma(3)-subunit) gene was considered to be a good candidate for the observed effects. Differences in the PRKAG3 gene sequences of the founder animals of the intercross were analyzed. The RN(-) mutation previously reported was not present in the cross but three missense substitutions and a polymorphic short interspersed element (SINE) were identified. To confirm the hypothesis that at least one of these mutations was associated with differences in meat quality, >1800 animals from several unrelated commercial lines were genotyped for the candidate substitutions and an association study was performed. The results demonstrate the presence of new economically important alleles of the PRKAG3 gene affecting the glycogen content in the muscle and the resulting meat quality. Haplotype analysis was shown to resolve the effects of PRKAG3 more clearly than analysis of individual polymorphisms. Because of their prevalence in the more common commercial breeds, the potential implications for the pig industry and consumers are considerably greater than the original discovery of the RN(-) mutation. Furthermore, these results illustrate that additional alleles of genes involved in major mutations may play a significant role in quantitative trait variation.

Alleles↗

Genetic differences in the frequency of the hinge variants of porcine IgA is breed dependent.

The distribution of the IgA(a) and IgA(b) alleles of porcine IgA in over 160 randomly-selected animals revealed an abundance of heterozygotes but only two b/b homozygotes. Since the IgA(b) allotype is a splice site mutant lacking two-thirds of the hinge, this study tests the hypothesis that pigs with this genotype may be at a selective disadvantage while heterozygous individuals may be at some advantage. This hypothesis was tested by collecting data on 374 animals of known breed and often parentage. We show here that when breed was not considered, young animals of known parentage had genotypic frequencies identical to that expected for Mendelian alleles but that a/b heterozygotes were overrepresented in adults. However, when analyzed with regard to breed, a very strong association between breed and the frequency of the IgA(a) and IgA(b) alleles was discovered. Meishan and NIH minipigs were homozygous for IgA while heterozygotes predominated in Berkshire, Chester White, Durocs, Hampshire and Landrace. Animals homozygous for IgA(b) were best represented in the White Cross line. We show here that this very strong breed dependency of IgA allotypy in swine can produce a sample bias that can explain why only two b/b homozygotes (1.3%) were found in the 160 randomly-selected samples since the original samples came from primarily Landrace and Yorkshire animals. The expected frequency of b/b homozygotes in these breeds would be <3%. Thus, the data presented here reject the hypothesis that swine homozygous for a trait that results in loss of two-thirds of the IgA hinge, are selected against and that heterozygotes are positively selected. Rather, the study shows that IgA(a) and IgA(b) appear to be simple, breed-dependent allotypic markers.

Alleles↗

Nitric oxide synthase and cGMP activity in the salivary glands of the American dog tick Dermacentor variabilis.

We colocalized nitric oxide synthase (NOS) activity in epithelial cells that surround the salivary gland duct in female Dermacentor variabilis with NADPH diaphorase histochemistry and immunohistochemistry using a polyclonal anti-endothelial NOS. Using size-exclusion chromatography, a fraction with a molecular mass of about 185 kDa that had diaphorase activity was eluted from tick salivary gland homogenate. This fraction converted arginine to citrulline with the production of nitric oxide (NO), which was detected by using electron spin resonance spectroscopy. The complete activity of the diaphorase fraction was dependent on NADPH, FAD, tetrahydrobiopterin, calmodulin, (CaM), and Ca(2+), but was not dependent on dithiothreitol. The arginine analog N(G)-monomethyl-L-arginine inhibited the activity of this fraction. NO and arginine activated soluble guanylate cyclase to produce cGMP in dopamine-stimulated isolated salivary glands. Dopamine-stimulated isolated salivary glands treated with tick saline containing either EDTA, the NOS inhibitor N(G)-nitro-L-arginine methyl ester, or the calcium/CaM binding inhibitor W-7 showed no increase in cGMP. The NO donor sodium nitroprusside significantly increased cGMP levels in unstimulated isolated salivary glands. A possible function for NO in salivation by this ixodid tick is discussed.

Animals↗

Comparative gene mapping workshop: progress in agriculturally important animals.

Following the successful Comparative Mapping Workshop held at Fraser Island, Australia in 1995, HUGO organized a second workshop of 41 invited participants, held at Toulouse, France on May 3 and 4, 1999. The aim of the conference was to focus on recent developments in genome mapping in a variety of vertebrate species, with particular emphasis on progress in farm animals (cattle, pigs, chickens, sheep, horses, goats, and deer). In addition, representatives from important experimental mammalian and vertebrate organisms (e.g. mice, rats, dogs, fugu, and marsupials) also participated in the meeting. After a rapid overview of developments in the construction and comparison of genome maps in a wide variety of species, discussion focused on how comparative genomics will play a vital role in the genetic dissection of multigenic traits and the characterization of agriculturally important loci in agricultural species. Acceleration of gene discovery with heterologous ESTs (Expressed Sequence Tags) or collections of ESTs was discussed. Recent developments in the construction of cDNA libraries and the efficiency of tools such as whole genome radiation hybrids (RH) and large fragment clone libraries (YACs and in particular BACs) were discussed. Proposed criteria to improve the identification of homologous genes between species and recommendations for nomenclatures were identified. Particular emphasis was placed on how the integration of biological databases could help the scientific community.

Agriculture↗

Porcine IgA allotypes are not equally transcribed or expressed in heterozygous swine.

The prediction of 1:1 expression of constant region allotypes in heterozygous animals assumes that productive VDJ rearrangements occur at random between chromosomes, switch recombination is random, there is no allele-related defect in switching and there is no selection for a B-cell receptor bearing a certain constant region allotype. In data reported here, this prediction was often not fulfilled for the transcripts encoding the IgAa and IgAb alleles of porcine IgA including those from late term fetal piglets that are not in contact with environmental antigens or maternal regulatory factors. In the spleen, thymus, mesenteric lymph node (MLN), ileal Peyer patches, parotid gland and PBLs of 5-week-old conventionally-reared Duroc pigs, ratios of IgAa to IgAb transcripts as high as 4:1 were observed. Since White Cross animals had significantly higher levels of IgAb than IgAa (some >3-fold), a allele-linked switch defect cannot explain the deviation from the expected 1:1 ratio. When the IgAa:IgAb ratios in older Durocs and those reared at a different site were studied, no evidence for breed dependence of differential transcription was found. Total serum IgA levels paralleled total transcript levels in PBLs while particularly in White Cross animals, the IgAa:IgAb ratio in serum was higher in many animals than the IgAa:IgAb transcript ratio in their PBLs. We conclude that deviations from the expected 1:1 ratio of allotype transcripts and secreted IgA in young pigs is normal and deviations from this ratio also occur during fetal life in the absence of environmental antigens and maternal regulatory factors. We speculate that postnatal deviations result from: (A) exposure to environmental antigens that selectively expand B-cells expressing V(H) gene alleles linked to either IgAa or IgAb or (B) some form of colostrum-dependent regulation. Pre-natal regulation may depend on the selection of B-cells bearing certain V(H) or C(H) encoded BCRs by stromal ligands such as fetal B-cell superantigens.

Animals↗

Lymphatic malformation: predictive factors for recurrence.

OBJECTIVE: Although lymphatic malformations are often found to be well circumscribed when surgery is undertaken in early childhood, complete surgical excision can be difficult when the lesion is infiltrative. This study retrospectively evaluates these patients in an attempt to identify prognostic factors that may predict recurrence. STUDY DESIGN AND SETTING: A retrospective chart review was conducted covering the years 1991 to 1998. Seventeen patients were identified having undergone 32 surgical resections of tumors described as lymphatic malformations. Data abstracted from the charts included the site of the lesion, surgical and histologic assessment of encapsulation, and status at follow-up examination. RESULTS: Six of 17 patients developed a recurrence after surgery. Correlation between recurrence and histologic or operative impressions of encapsulation was significant by chi(2) analysis (P<0.01). CONCLUSION: On the basis of the findings of this case series, lymphatic malformations that are found to be nonencapsulated and infiltrative by intraoperative or histologic assessment are more likely to recur.

Adolescent↗

Airway burns and atelectasis in an adolescent following aspiration of molten wax.

Scald injuries caused by hot liquids are not a frequently reported cause of pediatric respiratory and alimentary tract burns. Aspiration of molten wax with subsequent pharyngeal or laryngeal burns has not been described at all, to the best of our knowledge. A case of an adolescent who presented with airway burns and atelectasis subsequent to aspiration of molten wax is herein described and discussed.

Bronchi↗

An autosomal recessive, lethal, neurologic disease of Gordon Setter puppies.

This report details clinical, necropsy, and pedigree data on an inherited, lethal, neurologic disease of young Gordon Setters. This disorder is characterized by an early age of onset, gait and postural abnormalities, progressive weakness, and recumbency by 5-6 weeks of age. Although clinically distinctive, postmortem changes in affected pups were minimal. Gross lesions were not observed. Microscopic changes were subtle and consisted of astrocyte swelling, primarily in the cerebrocortical and cerebellar white matter, and white matter tracts of the brainstem. Immunohistochemistry for glial fibrillary acidic protein revealed a marked increase in the number and staining intensity of astrocyte cytoplasmic processes in affected pups compared with age-matched controls. Neither cerebral inflammation nor neuronal necrosis was identified. Pedigree analysis of affected litters demonstrated an autosomal recessive mode of inheritance. A diagnosis of this heritable disease should be based on the early age of onset (3-4 weeks of age), characteristic clinical signs, rapid progression to recumbency by 5-6 weeks of age, identification of swollen astrocytes primarily in the cerebellar and cerebrocortical white matter and white matter tracts of the brainstem, and the exclusion of other disease processes.

Animals↗

Effect of methoprene and 20-hydroxyecdysone on vitellogenin production in cultured fat bodies and backless explants from unfed female Dermacentor variabilis.

The effect of 20-hydroxyecdysone (20HE) and the juvenile hormone analogue methoprene (JHA) on vitellogenin (Vg) production in fat body organ cultures and backless explants of unfed female Dermacentor variabilis was measured. An indirect double antibody enzyme linked immunosorbent assay (ELISA) was developed using a monoclonal antibody that recognized a 98 kDa subunit of Vg and a Vg specific polyclonal antibody made against vitellin (Vn). Peak Vg titers in culture medium from fat body cultures treated with 0.1 &mgr;M 20HE or 1 &mgr;M 20HE were 24 ng/ml and 20 ng/ml respectively. In culture medium from backless explants treated with 0.1 &mgr;M 20HE or 1 &mgr;M 20HE, peak Vg titers were 36 ng/ml and 26 ng/ml, respectively. JHA produced only a slight increase in Vg titers that was statistically different from Vg titers produced by 20HE but was not statistically different from hormone-free controls. These results support the conclusion that Vg production in fat body trophocytes of D. variabilis is regulated by 20HE.

Journal Article↗

Sialoblastoma: clinicopathological/immunohistochemical study.

Sialoblastoma is an extremely rare salivary tumor diagnosed at birth or shortly thereafter with significant variability in histologic range and clinical course, so that for an individual case it may be difficult to predict the most appropriate therapy. We detail the case of a toddler noted to have a firm 1-2-cm mass in the left cheek at 21 months. Parotidectomy was performed at 26 months, revealing a sialoblastoma; the resection margins were positive. During the next 10 months, the mass recurred or persisted, necessitating numerous procedures. The tumor was composed of basaloid cells with fine chromatin and other more mature cuboidal epithelial cells. Ductules and solid organoid nests with some tendency toward peripheral pallisading were also noted. There was no perineural invasion; necrosis initially was sparse but increased over time. The mitotic rate also increased from 6 to 7/10 high-power fields in the first resection to 20/10 high-power fields in the last resection. Nuclear pleomorphism increased with time. The MiB1 proliferative index revealed a dramatic increase in the number of labeled nuclei: from 3 cells/10 high-power fields in the first specimen to 94 cells/10 high-power fields for the last specimen. Cytokeratin accentuated the ductal structures. S-100 showed a diffuse staining pattern, with darker staining of the spindled myoepithelial cells. The Her-2-neu protein showed moderate cytoplasmic staining, whereas the p53 showed only occasional labeling of nuclei. This is the first case of sialoblastoma with evidence of increasing anaplasia based on increasing proliferative capacity. Therefore, the distinction between benign and malignant sialoblastomas may not be as well defined as previously thought. The patient's prognosis is likely to be determined by the tumor grade as well as the stage at presentation and the extent of resection.

Biomarkers, Tumor↗

Idiopathic non-obstructive hypertrophic cardiomyopathy, vitamin B12 deficiency and gastric adenocarcinoma: an unreported association in a teenager.

UNLABELLED: A 14-year-old boy presented with anorexia and weakness whereon the diagnosis of dimorphic anaemia was made. An excellent response to iron and vitamin B12 was observed. In addition, the patient had non-obstructive hypertrophic cardiomyopathy. At endoscopy 2.5 years later, an adenocarcinoma was diagnosed and the patient underwent a high subtotal gastrectomy. To the best of our knowledge, this rare association has never been reported in children. CONCLUSION: We report a youngster with pernicious anaemia, associated with nonobstructive hypertrophic cardiomyopathy in whom gastric adenocarcinoma was found. Patients with pernicious anaemia are at greater risk of developing gastric carcinoma than the general population, therefore we recommend routine periodic gastroscopic surveillance in the paediatric population with pernicious anaemia.

Adenocarcinoma↗

Effect of gamma-interferon on binding of gliadin and other food peptides to the human intestinal cell line HT-29.

gamma-Interferon is one of the main cytokines released during activation of intestinal lymphocytes in coeliac patients. The question has never been addressed whether gamma-interferon influences binding of gliadin and other food peptides to human enterocytes. Therefore, the human intestinal epithelial cell line HT-29 was cultured with gliadin, casein, beta-lactoglobulin and ovalbumin, with or without gamma-interferon, and peptide binding to cells was determined by flow cytometry and fluorescence microscopy. gamma-Interferon stimulated gliadin binding by a factor of 4. Binding was saturable with half maximal binding at 0.15 mg/ml. For maximal binding, an incubation of at least 24 h was necessary. gamma-Interferon increased binding of beta-lactoglobulin and casein, too, but inhibited that of ovalbumin. Binding of gliadin was inhibited by the other peptides. Under the conditions of ongoing mucosal inflammatory reactions and release of gamma-interferon, enhanced binding may trigger intestinal lymphocytes, increase secretion of cytokines and thus induce a vicious circle.

Caseins↗