mRNA of luteal genes associated with progesterone synthesis, maintenance, and apoptosis in dairy heifers and lactating dairy cows.

This study was performed to investigate the role of corpus luteum (CL) in reduced pregnancy rates (PR) observed in high producing lactating dairy cows. Development of CL and secretion of progesterone (P(4)) play a key role in early embryo development, implantation, and maintenance of pregnancy. Time of ovulation was synchronized in dairy heifers and second/third parity lactating dairy cows and CL enucleated surgically under local anesthesia on day 10 of the estrous cycle. Quality of the CL in dairy heifers (n=5) and lactating dairy cows (n=5) was compared by analyzing the expression of candidate genes by mRNA assessments using quantitative real-time PCR. Amounts of mRNA for factors associated with P(4) synthesis: 3betaHSD, anti-apoptotic function: BCL2, angiogenesis: VEGF, IGF1, and FGF2, and luteal maintenance: IL1A were greater (P<0.05) in CL obtained from dairy heifers compared to that of lactating dairy cows. Also a greater ratio for BAX:BCL2 mRNA was observed in lactating cows. Therefore, genes regulating angiogenic, steroidogenic, and luteotropic factors are highly expressed in heifers compared to lactating dairy cows, whereas apoptosis seemed to be more evident in CL of lactating cows. These findings suggest that CL of lactating dairy cows have reduced luteotropic as well as steroidogenic capacities on day 10 of the estrous cycle and might have played a critical role in reduced PR observed in lactating dairy cows.

Pregnancy rates to timed artificial insemination in dairy cows treated with gonadotropin-releasing hormone or porcine luteinizing hormone.

We compared the effects of porcine luteinizing hormone (pLH) versus gonadotropin-releasing hormone (GnRH) on ovulatory response and pregnancy rate after timed artificial insemination (TAI) in 605 lactating dairy cows. Cows (mean+/-SEM: 2.4+/-0.08 lactations, 109.0+/-2.5 d in milk, and 2.8+/-0.02 body condition score) at three locations were assigned to receive, in a 2x2 factorial design, either 100 microg GnRH or 25mg pLH im on Day 0, 500 microg cloprostenol (PGF) on Day 7, and GnRH or pLH on Day 9, with TAI 14 to 18h later. Ultrasonographic examinations were performed in a subset of cows on Days 0, 7, 10, and 11 to determine ovulations, presence of corpus luteum, and follicle diameter and in all cows 32 d after TAI for pregnancy determination. In 35 cows, plasma progesterone concentrations were determined 0, 3, 4, 5, 6, 7, and 12 d after ovulation. The proportion of noncyclic cows and cows with ovarian cysts on Day 0 were 12% and 6%, respectively. Ovulatory response to first treatment was 62% versus 44% for pLH and GnRH and 78% versus 50% for noncyclic and cyclic cows (P<0.01). Location, ovulatory response to first pLH or GnRH, cyclic status, presence of an ovarian cyst, and preovulatory follicle size did not affect pregnancy rate. Plasma progesterone concentrations after TAI did not differ among treatments. Pregnancy rate to TAI was greater (P<0.01) in the GnRH/PGF/pLH group (42%) than in the other three groups (28%, 30%, and 26% for GnRH/PGF/GnRH, pLH/PGF/GnRH, and pLH/PGF/pLH, respectively). Although only 3% of cows given pLH in lieu of GnRH on Day 9 lost their embryo versus 7% in those subjected to a conventional TAI using two GnRH treatments, the difference was not statistically significant. In summary, pLH treatment on Day 0 increased ovulatory response but not pregnancy rate. Cows treated with GnRH/PGF/pLH had the highest pregnancy rate to TAI, but progesterone concentrations after TAI were not increased. In addition, preovulatory follicle diameter did not affect pregnancy rate.

Successful anticoagulation with hirudin in a patient with mesenteric venous thrombosis and multiple coagulation abnormalities.

A case of multiple thrombotic diatheses discovered in the setting of mesenteric venous infarction is discussed. The patient had deficiencies of protein C, protein S, antithrombin III; was heterozygous for factor V Leiden; and had polycythemia vera. Adequate anticoagulation could not be established with heparin administration and hirudin was used. The diagnosis of mesenteric venous infarction, thrombotic tendency of multiple coagulation diatheses, and use of hirudin are discussed.

Variations in adequate levothyroxine replacement therapy in patients with different causes of hypothyroidism.

OBJECTIVE: To compare the levothyroxine replacement dose in 181 patients with various causes of hypothyroidism. METHODS: We analyzed the dose of levothyroxine used in the following five patient groups: (1) 37 patients with hypothyroidism after radioiodine therapy for Graves' thyrotoxicosis who were receiving a stable (for at least 4 years) replacement dose (mean time after 131 I therapy, 11.3 years); (2) 36 patients with Hashimoto's hypothyroidism (chronic autoimmune thyroiditis with a goiter or positive test results for antithyroid antibodies); (3) 36 patients with central hypothyroidism; (4) 36 patients with hypothyroidism after near-total thyroidectomy and 131 I therapy for thyroid carcinoma with negative total-body 131 I scans who were euthyroid when receiving levothyroxine; and (5) 36 patients with atrophic thyroiditis (no goiter and negative test results for antithyroid antibodies). Adequacy of levothyroxine replacement dose was defined as a normal thyrotropin level and clinical euthyroidism in patients with primary hypothyroidism and a serum free thyroxine index in the upper half of the normal range in conjunction with clinical euthyroidism in patients with central hypothyroidism. RESULTS: The mean (+/- standard error of the mean) replacement dosage of levothyroxine (mg/kg per day) in patients with atrophic thyroiditis (1.26 +/- 0.07) was lower (P<0.05) than in patients with Hashimoto's hypothyroidism (1.59 +/- 0.07) and those with hypothyroidism after radioiodine therapy (1.56 +/- 0.05). These doses, in turn, were lower (P<0.01) than those in patients with central hypothyroidism (1.88 +/- 0.10) or euthyroid thyroid carcinoma (2.08 +/- 0.07). In a separate analysis, the levothyroxine dose in 43 patients with hypothyroidism after 131 I treatment was evaluated serially over time. The mean levothyroxine dosage increased from 0.87 +/- 0.12 at 6 months after 131 I therapy to 1.57 +/- 0.09 at 7 years (P<0.001). The serum thyrotropin concentration (in mU/mL) during levothyroxine therapy in patients with central hypothyroidism (0.31 +/- 0.08) was lower (P<0.01) than in patients with hypothyroidism after 131 I therapy (1.69 +/- 0.37), Hashimoto's hypothyroidism (1.39 +/- 0.20), atrophic thyroiditis (1.86 +/- 0.22), and euthyroid thyroid carcinoma (1.48 +/- 0.26). CONCLUSION: The levothyroxine replacement dose varies with the cause of the hypothyroidism.

Isolation and characterization of the c-fos(rat) cDNA and analysis of post-translational modification in vitro.

c-fos mRNA accumulates to a level of 0.2% of cellular poly(A)-containing RNA 45 min after treatment of rat pheochromocytoma (PC12) cells with 1 mM barium chloride. Several clones of the c-fos(rat) cDNA were isolated from a cDNA library constructed from this RNA population. Nucleotide sequence analysis of a full-length cDNA clone reveals striking conservation among the c-fos genes isolated from rat, mouse and human cells, and confirms the c-fos gene structure predicted from an analysis of c-fos genomic clones. Translation of an SP6-derived transcript of the c-fos(rat) cDNA in a messenger-dependent rabbit reticulocyte lysate yields the complete c-fos protein. It undergoes extensive post-translational modification in the lysate, particularly in the presence of additional cAMP. The c-fos protein synthesized in vitro appears to be phosphorylated by the cAMP-dependent protein kinase.