Alloplasmic male sterile Brassica napus with Enarthrocarpus lyratus cytoplasm: introgression and molecular mapping of an E. lyratus chromosome segment carrying a fertility restoring gene.

A cytoplasmic male sterility (CMS) system for Brassica napus (2n = 38; AACC) was developed by backcross substitution of its nucleus into the cytoplasm of a wild crucifer, Enarthrocarpus lyratus. Male sterility was complete, stable, and expressed in small flowers with rudimentary anthers. Since the B. napus germplasm lines were complete or partial maintainers of male sterility, the required fertility restorer gene (Rfl) was introgressed from the cytoplasm donor species. Inheritance studies carried out on F1 and F2 populations derived from hybridizing cytoplasmic male sterile and male fertile near-isogenic (PNILs) lines of B. napus 'Westar', revealed a monogenic dominant control for fertility restoration. Bulked segregant analysis with 215 RAPD primers helped in the identification of putative primers associated with fertility restoration. Co-segregation analysis of eight such primers with Rfl gene revealed two markers, OPK 15700 and OPZ 061300, which flank the Rfl locus on either side at a distance of 8.2 and 2.5 cM, respectively. These DNA markers will be useful in marker-assisted selection for improving the commercial potential of this newly developed CMS-fertility-restorer system for hybrid seed production programs in rapeseed.

Synthesis of intergeneric hybrids and establishment of genomic affinity between Diplotaxis catholica and crop Brassica species.

Intergeneric hybrids of the wild crucifer Diplotaxis catholica (2n = 18, D(C)D(C)) as female with two crop Brassica species, namely Brassica rapa (2n = 20; AA) and Brassica juncea (2n = 36; AABB) as male, were developed, using ovary and sequential culture. Reciprocal crosses were not successful, suggesting unilateral cross incompatibility. Morphologically, the hybrid plants resembled the crop brassica parents, but were nearly male- as well as female-sterile. Induction of amphiploidy helped to improve pollen fertility for the D. catholica x B. rapa cross (73%), but less so for the D. catholica x B. juncea cross (35-40%). Female fertility was also higher in both the amphiploids. Cytological analysis of the F(1) hybrids revealed aberrant meiosis with predominant occurrence of the univalents. Partial genomic homoeology between the A genome of B. rapa and the D(C) genome of D. catholica was indicated by the presence of up to five bivalents in 14.7% of the PMCs in the D. catholica x B. rapa hybrid, and 1-2 trivalents or a quadrivalent in nearly 44% of the PMCs in the derived amphiploid. In the second cross, D. catholica x B. juncea, up to six bivalents and one trivalent were observed indicating homoeology between the A/B genomes of B. juncea and the D(C) genome of D. catholica. The possibility of introgression of desirable genes from D. catholica into crop Brassica species exists in view of significant affinity between the D(C) and A/B genomes.

Eosinophilic granuloma of the mandibular condyle. A case report and management discussion.

The occurrence of eosinophilic granuloma in the mandibular condyle has been reported in only three cases. An additional case of eosinophilic granuloma of the mandibular condyle is reported. The lesion presented was treated with condylectomy and surgical curettage. There was no recurrence or soft tissue involvement on annual postoperative examination. Secondary reconstruction was planned but was not required.

Oral squamous cell carcinoma in identical twins: report of a case.

This case report describes two middle-aged identical female twins with a mild to moderate history of tobacco and alcohol abuse who developed squamous cell carcinomas in the same anatomic sites. By exclusion of major factors, a correlation between heredity and the incidence of cancer in these cases appears likely; however, carcinogenic agents (tobacco and alcohol) must also be considered as contributing factors. Close observation of siblings (and certainly twins) is recommended when head and neck carcinoma occurs prior to middle age. Although no genetic population prone to oral cancer is known, the disease is rare enough in younger individuals to raise the question of a possible genetic predisposition.

Bilateral fixation of a nasotracheal tube by transfacial Kirschner wires.

Because of the high margin for error with transfacial internal wire fixation, even in the hands of an experienced practitioner, alternative modalities in the treatment of zygomaticomaxillary complex fractures should be considered. When the use of transfacial rigid wire fixation is indicated, emphasis should be placed on prevention and early recognition of nasotracheal transfixation to avoid unnecessary postoperative catastrophies.