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F V White

Publications and source records attributed to F V White.

23 records · Page 2Linked to original sources

Isolation and analysis of chemosensory behavior mutants in Drosophila melanogaster.

A behavioral countercurrent paradigm has been developed for assaying the chemotactic responses of wild-type and mutant Drosophila melanogaster adults. Oregon R males avoid both quinine sulfate and NaCl, whereas Oregon R females reject the quinine salt but are attracted to NaCl when tested in this paradigm. Wild-type behavior is sufficiently reproducible to allow identification of mutants affecting chemotaxis, and 12 such mutants, in six complementation groups, have now been isolated. Three of the mutants respond abnormally to NaCl, two in one complementation group with atactic behavior (no chemotaxis) and the other, in a separate group, with a mistactic response (attraction to the stimulus). Four mutants in another group respond mistactically to quinine sulfate. Of the remaining mutants, two in one group behave atactically and three, in two groups, respond mistactically to either chemical stimulus. Several of the mutants also show abnormal behavior in a proboscis extension assay when tested individually with sucrose solutions.

Animals↗

Bannayan-Riley-Ruvalcaba syndrome: spectrum of intestinal pathology including juvenile polyps.

Bannayan-Riley-Ruvalcaba syndrome (BRRS) is a disorder that includes juvenile polyposis as part of its pathologic spectrum, and it recently has been shown to share phenotypic and genotypic features with Cowden's disease. In existing literature, descriptions of intestinal pathology in patients with BRRS are relatively sparse and occasionally erroneous. We describe the intestinal pathology in multiple specimens from three children with BRRS. Examination of gastrointestinal biopsies from these children revealed predominantly colonic and rectal polyps with the histology of juvenile polyps. Additionally, two cases with clusters of ectopic ganglion cells within the lamina propria, one in a colonic polyp and one in a duodenal biopsy, and an atypical polyp were observed. Bannayan-Riley-Ruvalcaba syndrome should be included in the list of differential diagnostic considerations when a child or young adult presents with a juvenile polyp, particularly if unusual histologic features such as atypical polyps or ectopic ganglion cells are encountered.

Adenomatous Polyposis Coli↗

Circumferential distribution of ganglion cells in the transition zone of children with Hirschsprung disease.

We prospectively studied the circumferential distribution of ganglion cells in the transition zone from a study population of 21 patients with Hirschsprung disease (HD) undergoing a pull-through procedure over a 26-month period. Twelve cases were satisfactory for examination, in that the transition zone was contained within a single surgical specimen and specimen distortion was minimal. Ganglion cells in the submucosa were counted in all 12 cases. In seven of the cases, the transition zone was proximal to the rectal sleeve and myenteric plexus ganglion cells were also counted. We found an uneven circumferential distribution of ganglion cells in both myenteric plexus and submucosa of the transition zone, resulting in a "leading edge" of ganglion cells extending into aganglionic distal bowel. The maximum length of this leading edge was 2.4 cm and 2.1 cm in the myenteric plexus and submucosa, respectively. Ganglion cells at the tip of the leading edge were present in clusters of up to six ganglion cells, in marked contrast to an absence of ganglion cells for most of the remainder of the circumference. Closely spaced myenteric plexus ganglia were seen at the tip of the leading edge in some cases. The leading edge was more frequently observed along the antimesenteric side, but this was not statistically significant. Our findings have relevance in the interpretation of intraoperative biopsies at the time of pull-through surgery and subsequent biopsies of neorectum in patients with surgically corrected HD.

Biopsy↗

Alveolar capillary dysplasia with misalignment of pulmonary veins and anterior segment dysgenesis of the eye: a report of a new association and review of the literature.

The association of alveolar capillary dysplasia with misalignment of pulmonary veins (ACD-MPV) and ocular abnormalities has not been previously reported. We present a case of ACD-MPV and anterior segment dysgenesis of the eye in a full-term infant as well as a review of the relevant literature.

Abnormalities, Multiple↗

Fetal parvovirus B19 infection and liver disease of antenatal onset in an infant with Ebstein's anomaly.

Fetal parvovirus B19 infection has been reported in association with hydrops and fetal demise, myocarditis, and congenital anomalies, as well as with normal outcome of pregnancy. One infant with liver disease of fetal onset associated with parvovirus B19 infection has been described. We have seen another such infant, in whom marked siderosis of the liver suggested accelerated destruction of erythrocytes and portal tract fibrosis with proliferation of bile ducts suggested intrauterine infection. Viral cytopathic effects were not seen. Maternal serum obtained postpartum contained IgM class antibodies against parvovirus B19, and parvovirus B19 nucleic acid sequences were identified in the infant's liver by polymerase chain reaction studies. We propose that recognition of this combination of siderosis with fibrosis and bile duct proliferation will permit identification of cases of fetal parvovirus B19 infection.

Ebstein Anomaly↗