Modern freshwater microbialite analogues for ancient dendritic reef structures.

Microbialites are organosedimentary structures that can be constructed by a variety of metabolically distinct taxa. Consequently, microbialite structures abound in the fossil record, although the exact nature of the biogeochemical processes that produced them is often unknown. One such class of ancient calcareous structures, Epiphyton and Girvanella, appear in great abundance during the Early Cambrian. Together with Archeocyathids, stromatolites and thrombolites, they formed major Cambrian reef belts. To a large extent, Middle to Late Cambrian reefs are similar to Precambrian reefs, with the exception that the latter, including terminal Proterozoic reefs, do not contain Epiphyton or Girvanella. Here we report the discovery in Pavilion Lake, British Columbia, Canada, of a distinctive assemblage of freshwater calcite microbialites, some of which display microstructures similar to the fabrics displayed by Epiphyton and Girvanella. The morphologies of the modern microbialites vary with depth, and dendritic microstructures of the deep water (> 30 m) mounds indicate that they may be modern analogues for the ancient calcareous structures. These microbialites thus provide an opportunity to study the biogeochemical interactions that produce fabrics similar to those of some enigmatic Early Cambrian reef structures.

Human skin contains luteinizing hormone/chorionic gonadotropin receptors.

Normal human skin contains a major 4.5 kb and several minor mRNA transcripts and a 66 kDa protein of luteinizing hormone (LH)/chorionic gonadotropin (hCG) receptors which are capable of binding exogenous 125I-hCG. The distribution of receptor transcripts and receptor protein are the highest in epidermis followed by hair follicles, sebaceous and sweat glands. LH/hCG receptors are co-localized with androgen receptors in all the skin appendages. These data are the first demonstration of skin containing LH/hCG receptors and would suggest that LH and hCG may regulate skin functions.

Contribution of consultants to care of compromised pregnancies.

Obstetricians often seek consultative services of other specialists in the management of compromised pregnancies. However, the extent of such consultations and the contribution of these consultants have not been addressed in the literature. This study is addresses the contribution of consultants to the care of complicated pregnancies at a tertiary care center. During the 2 1/2 years of this retrospective study, 2263 antepartum admissions were made for pregnancy complications. One hundred sixty-six of those patients were hospitalized 176 times and were treated by one or more consulting physicians for a consultation rate of 7.8%. Eighteen specialties were consulted, including 54 (32%) consultations from maternal fetal medicine, 44 (24%) from internal medicine, 28 (16%) from general surgery, and 22 (12%) from endocrinology. Of the initial admission diagnoses, 87.9% were confirmed and 46 new diagnoses were made by the consultants. A significant positive correlation was noted between the number of consultants, maternal length of hospital stay, and maternal hospitalization cost.

Subtotal reconstruction of the hemimandible with an autogenous cancellous bone and marrow graft.

The use of an autogenous cancellous bone and marrow graft for subtotal reconstruction of the mandible is illustrated with a case report. The rationale of the treatment plan and the operative technique are discussed. Three years of postreconstruction follow-up examinations show good results with this technique.