Genome-wide association study identifies variants associated with hair length in Brangus cattle.

Thermal stress limits beef cattle production and a shorter hair coat is a key thermoregulative adaptation that allows cattle to lose heat more efficiently. The objective of this study was to identify genetic variants associated with the length of the undercoat and topcoat of cattle utilizing 1456 Brangus heifers genotyped with the Bovine GGP F250 array. Seven SNPs in the PCCA gene were significantly associated with undercoat length. PCCA belongs to the biotin transport and metabolism pathway. Biotin deficiency has been reported to cause hair loss. Four SNPs in an 110 kb including a missense mutation in the PRLR gene were significantly associated with topcoat length. Whereas the association of this polymorphism with hair length is novel, the SLICK mutation in PRLR has previously been demonstrated to significantly impact hair length in cattle. These newly detected genetic variants may contribute to a shorter hair coat and more thermotolerant animals.

Antimicrobial agents: pharmacology and clinical application in obstetric, gynecologic, and perinatal infections.

The pharmacology of selective antimicrobial agents and their role in the treatment of obstetric, gynecologic, and neonatal infections is the focus of this clinical review. Defining and refining the use of antimicrobial therapy is significant on both an individual and a global level because the emergence of resistant organisms is a public health concern. Heath care providers must be knowledgeable about the risks and benefits of initiating pharmacologic treatment based on clinical evidence with regard to an agent's spectrum of activity, efficacy, and side effects.

Direct entry midwifery education. Evaluation of program innovations.

During the 1996-1997 academic year, the State University of New York Health Science Center at Brooklyn, in partnership with North Central Bronx Hospital, implemented the first direct entry (DE) midwifery education program to be preaccredited by the American College of Nurse-Midwives. Five DE midwifery students were admitted and graduated. During their one-year course of studies, these students were provided supplementary didactic and clinical instruction in the medical sciences and basic health skills in addition to the identical course of midwifery studies offered to their registered nurse-student peers. The experience of students and faculty during this first year was that there was no significant difference in academic performance between the DE and nurse-midwifery students. Moreover, once oriented to the clinical environment, DE students progressed through the clinical practicums, and acquired entry-level midwifery skills, at a pace equivalent to that of their nurse peers and consonant with all expectations of safe practice. In addition, the Basic Health Skills and Integrated Medical Science course offerings served as effective instructional supplements to the curriculum by providing DE students with an opportunity to equalize their knowledge base with that previously acquired by registered nurse-prepared students; an unanticipated discovery was that some nurse-midwifery students could equally benefit from enrollment in these courses.

Pharmacologic management of sexually transmitted diseases.

Vaginal complaints account for a significant proportion of visits to health care providers and are an ongoing challenge to every clinician in terms of diagnosis and management. Midwives traditionally have viewed such complaints as a disruption of the vaginal ecosystem and have adopted a combination of pharmacologic and nonpharmacologic treatment modalities in the management of vulvovaginitis and sexually transmitted diseases. This article presents a review of the literature that focuses primarily on the pharmacologic management of some of the more common sexually transmitted diseases. The management of vulvovaginal candidiasis and bacterial vaginosis also is reviewed. Although neither condition is sexually transmitted, they always should be considered in the differential diagnosis of vaginal complaints.

Tyrosine hydroxylase-containing neurons in the spinal cord of the chicken. I. Development and analysis of catecholamine synthesis capabilities.

1. The development of tyrosine hydroxylase-immunoreactive (TH-IR) neurons was examined in the spinal cord of the chick embryo and hatchling. 2. Two groups of TH-IR cells are described, both of which appear to reach their full complement in number relatively late in embryonic development. One group is comprised of numerous cells located ventral to the central canal which make direct contact with the lumen of the canal. The other group consists of large multipolar neurons that reside in the dorsal horn, more commonly along the outer margin of the gray matter within lamina I and II, and less frequently deeper in the dorsal horn within medial portions of laminae V, VI or VII. 3. TH-IR cells ventral to the central canal in the chick are comparable in location to dopamine (DA)-containing spinal cord cells in lower vertebrate species. In contrast, the dorsally-suited TH-IR cells in the chick are known only to occur in similar positions in higher vertebrates. Therefore, the chick is novel in that the presence of both groups of TH-IR cells appearing together in significant numbers within the spinal cord has not been shown in any other species studied to date. 4. The TH-containing cells in the chick cord do not appear to contain the catecholamine biosynthesis enzymes, DBH or PNMT. Moreover, using anti-DA immunocytochemistry, neither group of TH-IR cells demonstrated detectable levels of DA in control animals nor in animals pretreated with inhibitors of MAO (MAO-I). 5. However, a difference was noted though between the two TH-IR cell groups in terms of their responses to exogenously supplied L-DOPA, the immediate precursor to DA. With the administration of L-DOPA and a MAO-I to chick hatchlings, cells in the region ventral to the central canal stained intensely for DA. In contrast, the same treatment failed to produce DA-immunoreactive cells in the dorsal horn. 6. One reasonable hypothesis for these results is that the TH-IR cells ventral to the central canal contain an active form of AADC, the enzyme that converts L-DOPA to DA. With this interpretation, if these cells can produce DA from L-DOPA, yet do not appear to synthesize DA endogenously, it would appear that the TH enzyme contained in these cells occurs in an inactive form. Whether the TH enzyme in the dorsally located immunoreactive cells is also inactive is uncertain since it remains unclear whether they contain AADC.