Biomedical subjects

James R Wright

Publications and source records attributed to James R Wright.

39 records · Page 3Linked to original sources

PubMed2002

The immunoprotective effect of Sertoli cells coencapsulated with islet xenografts is not dependent upon Fas ligand expression.

Coencapsulation with Sertoli-enriched testicular cell fractions prolongs islet graft survival time compared with islet encapsulation alone in a highly discordant tilapia (fish)-to-mouse xenotransplantation model. Here we investigate whether Fas ligand (Fas-L) expression by testicular Sertoli cells is responsible for this additional protective effect. Sertoli-enriched testicular cell fractions (7 x 10(6) cells) harvested from either Fas-L-defective (group I) or Fas-L-positive (group II) mice were coencapsulated in alginate gel spheres with fish islets and then transplanted into streptozotocin-diabetic Balb/c recipients. Group III mice received encapsulated islets without coencapsulated Sertoli cells. After transplantation, blood glucose levels were monitored three times per week. Mean graft survival times for the three groups were: group I = 35.6 +/- 10.2 days (n = 9), group II = 31.3 +/- 9.4 days (n = 7), and group III = 23.3 +/- 2.2 days (n = 6) (ANOVA, p = 0.043). Coencapsulation, regardless of the Fas-L status of the Sertoli cell donors, modestly prolonged graft survival. There was no significant difference between Fas-L-deficient and Fas-L-positive donors. Our results suggest that Fas/Fas-L interaction is not responsible for the additional protection afforded to encapsulated discordant islet xenografts by coencapsulation with Sertoli cells.

Alginates↗

PubMedDate not supplied

Association between Breus' mole and partial hydatidiform mole: chance or can hydropic villi precipitate placental massive subchorionic thrombosis?

Breus' mole (massive subchorionic hematoma) is a rare entity most often found in the placentae of macerated stillborn fetuses. Previously considered to represent a postmortem event, recent evidence suggests that it occurs prior to fetal demise. A 23-week gestation male neonate was delivered of a 23-year-old gravida 3, para 2 woman and survived for 49 min. An autopsy with chromosomal studies resulted in a diagnosis of triploidy. Placental examination showed the presence of both Breus' mole and also partial hydatidiform mole. DNA samples extracted from portions of the fresh hematoma and from the fetal spleen were compared using molecular techniques. PCR analysis showed the presence of Y chromosome specific DNA in the placental clot, but a semiquantitative Southern blot demonstrated that roughly 85% of the clot DNA was of maternal origin. These findings suggest that Breus' mole represents primarily maternal thrombosis rather than fetal hemorrhage. We hypothesize that the partial mole could have contributed to the formation of the Breus' mole as some of the hydropic villi may have focally obstructed the maternal venous return from the intervillus space causing sluggish flow and promoting thrombosis. A review of the literature on Breus' mole shows that the majority of reported cases have not included cytogenetic findings. However, several authors have reported an association with triploidy and other chromosomal anomalies characterized by scattered placental hydropic villi. Thus, we suggest that obstruction of maternal venous return by hydropic villi may have played a contributory role in some of these other reported cases.

Adult↗

PubMedDate not supplied

A rare case of interstitial del(1)(p34.3p36.11) diagnosed prenatally.

We report a very rare constitutional interstitial deletion of chromosome 1p defined within 1p34.3-36.11 bands with an intact pter. The diagnosis was made by standard cytogenetics and fluorescence in situ hybridization (FISH) studies on a cordocentesis specimen obtained at 21 weeks gestation. Termination of pregnancy was performed at 22 weeks gestation due to the ultrasound diagnosis of congenital heart disease. Autopsy confirmed congenital heart disease (cardiomegaly, Ebstein's anomaly, secundum atrial septal defect, subendocardial fibroelastosis), pulmonary lymphangiectasis, a high arched palate, short neck, and bilateral long proximally implanted thumbs. To our knowledge, this is the first case of del(1) (p34.3p36.11) diagnosed prenatally.

Abnormalities, Multiple↗