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Biomedical subjects

D R Klein

Publications and source records attributed to D R Klein.

12 recordsLinked to original sources
PubMed1999

Cytochrome b phylogeny of North American hares and jackrabbits (Lepus, lagomorpha) and the effects of saturation in outgroup taxa.

Jackrabbits and hares, members of the genus Lepus, comprise over half of the species within the family Leporidae (Lagomorpha). Despite their ecological importance, potential economic impact, and worldwide distribution, the evolution of hares and jackrabbits has been poorly studied. We provide an initial phylogenetic framework for jackrabbits and hares so that explicit hypotheses about their evolution can be developed and tested. To this end, we have collected DNA sequence data from a 702-bp region of the mitochondrial cytochrome b gene and reconstructed the evolutionary history (via parsimony, neighbor joining, and maximum likelihood) of 11 species of Lepus, focusing on North American taxa. Due to problems of saturation, induced by multiple substitutions, at synonymous coding positions between the ingroup taxa and the outgroups (Oryctolagus and Sylvilagus), both rooted and unrooted trees were examined. Variation in tree topologies generated by different reconstruction methods was observed in analyses including the outgroups, but not in the analyses of unrooted ingroup networks. Apparently, substitutional saturation hindered the analyses when outgroups were considered. The trees based on the cytochrome b data indicate that the taxonomic status of some species needs to be reassessed and that species of Lepus within North America do not form a monophyletic entity.

Animals↗
PubMed1983

Nucleotide sequence of the cDNA encoding the precursor of the beta subunit of rat lutropin.

We have determined the nucleotide sequences of cDNAs encoding the precursor of the beta subunit of rat lutropin, a polypeptide hormone that regulates gonadal function, including the development of gametes and the production of steroid sex hormones. The cDNAs were prepared from poly(A)+ RNA derived from the pituitary glands of rats 4 weeks after ovariectomy and were cloned in bacterial plasmids. Bacterial colonies containing transfected plasmids were screened by hybridization with a 32P-labeled cDNA encoding the beta subunit of human chorionic gonadotropin, a protein that is related in structure to lutropin. Several recombinant plasmids were detected that by nucleotide sequence analyses contained coding sequences for the precursor of the beta subunit of lutropin. Complete determination of the nucleotide sequences of these cDNAs, as well as of cDNA reverse-transcribed from pituitary poly(A)+ RNA by using a synthetic pentadecanucleotide as a primer of RNA, provided the entire 141-codon sequence of the precursor of the beta subunit of rat lutropin. The precursor consists of a 20 amino acid leader (signal) peptide and an apoprotein of 121 amino acids. The amino acid sequence of the rat lutropin beta subunit shows similarity to the beta subunits of the ovine/bovine, porcine, and human lutropins (81, 86, and 74% of amino acids identical, respectively). Blot hybridization of pituitary RNAs separated by electrophoresis on agarose gels showed that the mRNA encoding the lutropin beta subunit consists of approximately 700 bases. The availability of cDNAs for both the alpha and beta subunits of lutropin will facilitate studies of the regulation of lutropin expression.

Amino Acid Sequence↗
PubMed1983

Laryngeal edema as a complication of chemical peel.

Laryngeal edema is a rare complication in patients undergoing chemical face peels. Symptoms of stridor, hoarseness, and tachypnea developed within 24 hours after peeling and subsided within another 24 hours after inhalation therapy with heated aerosol mist was begun. All patients who developed this complication were heavy smokers. A possible mechanism by which this complication was produced is discussed and experience with a drug regimen to prevent its occurrence is presented.

Chemexfoliation↗
PubMed1981

Comparison of complications between in-hospital patients and out patients for aesthetic surgical procedures: a ten-year study.

On the basis of the clinical evidence and the statistical analysis of the 10-year survey, this study would confirm our hypothesis that in the surgical procedures performed-rhytidectomy and augmentation mammaplasty-there is no significant difference in the rate of serious complications between the inpatient group and the outpatient group. It would seem appropriate that further studies should be undertaken to evaluate other procedures and other ;complications. If we are to embark further on the course of out patient aesthetic surgery, we must strive for greater statistical knowledge in the area of complications and risk factors to evaluate our results better, keeping in mind our ultimate goal of continually improving our art.

Breast↗
PubMed1977

The use of the carbon dioxide laser in plastic surgery.

For centuries, surgical technics have included sharp metal instruments for incisions and dissections together with time-consuming clamping and tying of vessels with associated blood loss. The CO2 laser presents the first major change in these basic technics. Our brief experience with the Sharplan 791 indicates consistently marked reduced blood loss, less postoperative edema, and less postoperative pain with no increased risk to the patient and no compromise in the end results. Admittedly, much more investigation is necessary to determine its full potential, and perhaps its contraindications. However, it would appear at this time that the proper use of this new modality should be incorporated into our armamentarium of tools for plastic surgical advantages consistent with sound surgical judgment.

Carbon Dioxide↗
PubMedDate not supplied

Nutritional encephalomalacia in turkeys: diagnosis and growth performance.

An outbreak of neurological disease in 2 1/2-to-3 1/2-week-old male turkey poults was diagnosed morphologically as nutritional encephalomalacia. About 20 to 30% of the flock of 6360 showed clinical signs, which included going down with legs extended or hock-sitting and inability to get up, incoordination, weakness, staggering, trembling, torticollis, and opisthotonus. The most important gross postmortem changes were found in the brain, which consisted of an enlarged and swollen cerebellum with focal and/or diffuse hemorrhages. Major histopathological alterations included congestion, hemorrhages, necrosis, and malacia associated with hyaline capillary thrombi affecting the cerebellar cortex and adjacent white matter. Except for a slightly higher mortality, flock performance compared favorably with performance of other flocks grown in the same farm as well as with the national average for market tom turkeys.

Animal Feed↗