Time-dependent changes in pregnancy-associated glycoproteins and progesterone in commercial crossbred sheep.

The ruminant placenta functions as an endocrine and paracrine organ secreting proteins, growth factors, and steroid hormones, including pregnancy-associated glycoproteins (PAG), proteins with elusive function, which are readily detectable in maternal serum after placental attachment. In sheep, circulating progesterone beyond gestational Day 50 is predominantly of placental origin. The relationship among placental secreted factors, including progesterone, remains uncertain in sheep. The first aim of the study was to determine the relationship between gestational PAG profiles-using two commercial ELISA assays-progesterone, and fetal growth during pregnancy. The second aim of the study was to assess the presence and clearance of PAG in neonatal lambs and peripartum ewes in commercial crossbred sheep. Maternal serum samples were collected during mid-pregnancy and assayed for PAG1, pregnancy-specific protein B (PSPB), and progesterone. Maternal serum samples were also collected weekly starting 1-month prepartum until 10 weeks postpartum. Serum samples from newborns were collected at birth until Day 12 after birth and assayed for PAG1. Circulating maternal PAG1 concentrations steadily increased throughout mid-gestation, whereas PSPB exhibited a bimodal pattern of secretion. A strong positive correlation was observed between progesterone and PAG1 (r2 = 0.779, P < 0.0001), but not between PSPB and progesterone. No relationship was found between placental factors (PAG1, PSPB, and progesterone) and fetal size. PAG1 concentrations were lower before and after parturition in singleton compared with twin pregnancies (P < 0.05). Maternal PAG1 concentrations began declining at parturition and continued to decline until 10 weeks after parturition (P < 0.05). In newborns, PAG1 concentrations continuously declined in both singleton and twins regardless of sex (P < 0.05) and cleared from newborn serum by 12 days after birth. Our findings reported for the first time how different assays used to determine circulating PAG concentrations display different gestational profiles in sheep and how it allows the differentiation between singleton and multiple pregnancies. In conclusion, the strong correlation between PAG1 and progesterone during gestation reports that PAG1 can be effectively used as a marker of placental function.

Inheritance and mapping of 11 avirulence genes in Phytophthora sojae.

Two new crosses involving four races (races 7, 16, 17, and 25) of the soybean root and stem rot pathogen Phytophthora sojae were established (7/16 cross; 17/25 cross). An F2 population derived from each cross was used to determine the genetic basis of avirulence towards 11 different resistance genes in soybean. Avirulence was found to be dominant and determined by a single locus for Avr1b, 1d, 1k, 3b, 4, and 6, as expected for a simple gene-for-gene model. We also observed several cases of segregation, inconsistent with a single dominant gene being solely responsible for avirulence, which suggests that the genetic background of the different crosses can affect avirulence. Avr4 and 6 cosegregated in both the 7/16 and 17/25 crosses and, in the 7/16 cross, Avr1b and 1k were closely linked. Information from segregating RAPD, RFLP, and AFLP markers screened on F2 progeny from the two new crosses and two crosses described previously (a total of 212 F2 individuals, 53 from each cross) were used to construct an integrated genetic linkage map of P. sojae. This revised genetic linkage map consists of 386 markers comprising 35 RFLP, 236 RAPD, and 105 AFLP markers, as well as 10 avirulence genes. The map is composed of 21 major linkage groups and seven minor linkage groups covering a total map distance of 1640.4cM.

Frontier medicine: the future and integrative medicine.

Vigorous and prolonged effort is required to gain true mastery of the healing arts. Conventional and complementary medicine have complementary strengths and weaknesses. Like the yin and yang of traditional Chinese medicine, they naturally flow into one another by a process of induction, creating balance. Integrative medicine is the frontier; it is the future. If we are to progress beyond our current understanding and ability to heal, we must work with theoretic models that allow us and our perception to operate "outside the box." For some, this understanding is intuitive. It is through cooperative and collaborative efforts of intuitively adept and technologically adept minds that we can integrate and advance our understanding; increase our ability to predict, prevent, and diagnose disease; and expand our therapeutic options.

Fate of infected and eroded hemodialysis grafts and autogenous fistulas.

Between 1970 and 1991, we placed 1,090 grafts (bovine and polytetrafluoroethylene) in 1,041 patients and created 1,034 autogenous fistulas in 856 patients for hemodialysis. Subsequent revisions for complications resulted in a total of 3,944 operations performed in patients with grafts and 1,633 operations in patients with autogenous fistulas. A total of 255 infections developed in 158 of the patients with grafts, whereas 8 infections developed in 7 patients with autogenous fistulas. The puncture infection rate was 5%/yr (12%/yr for a second puncture infection). The clean wound infection rate was 3% for grafts and 0.4% for autogenous fistulas. We made an attempt to salvage the graft, usually with a segmental bypass, in 75% of patients with a graft infection. Grafts were salvaged in 80% of patients in whom salvage was attempted (60% of all patients with an infection). The results in the few patients with infected autogenous fistulas were relatively poor.

Streptokinase dissolution of a right atrial thrombus associated with a temporary pacemaker.

Thrombosis of intravascular catheters is a well-recognized and potentially serious complication, which has been treated successfully with thrombolytic agents. A routine echocardiogram in a patient with a temporary transvenous pacemaker demonstrated a large thrombus attached to the pacing electrode. This was dissolved successfully and uneventfully with high-dose intravenous streptokinase therapy. To our knowledge, this is the first report of the successful lysis of a right atrial thrombus complicating a temporary transvenous pacemaker.

Transluminal angioplasty versus surgical repair for stenosis of hemodialysis grafts. A randomized study.

A randomized study of transluminal angioplasty versus surgical revision for stenosis at the venous end of hemodialysis grafts was carried out. Median patency for the surgical group was 12 months versus only 4 months for the transluminal angioplasty group. This difference was statistically significant (p less than 0.01). In addition, the average cost for surgical revision was slightly less than that for transluminal angioplasty. Therefore, for long-term patency, surgical treatment is the method of choice, although under special circumstances there may still be a role for transluminal angioplasty.

Scribner shunt conversion to arteriovenous fistula.

Scribner shunts were converted to arteriovenous fistulas in twenty-six patients, with long-term success in twenty patients. Infection with loss of the fistula was a problem in two patients. The fistulas were used for home as well as center dialysis and as a primary blood access site as well as a backup site.