Possible sites of ultrafiltration in Tubifex tubifex Müller (Annelida,Oligochaeta)

Summary The endothelia of Tubifex tubifex Müller consist of myoendothelial cells, chloragocytes, or podocytes. The latter seem to occur only as windows on the ventral vessel which has an endothelium of myoendothelial cells elsewhere. The podocytes are large cells, with several processes on the inner side which ramify into several pedicels. These are aligned upon the outside of the basement membrane which lines the inside of the endothelium. The gaps between adjacent pedicels are about 40 nm wide. In capillaries fenestrated endothelia occur with irregular spacings measuring up to 0.4–1 m. A diaphragm in podocytes or capillary fenestrations do not seem to exist. The basement membrane is the only continuous layer lining the blood vessels and capillaries of Tubifex with a rather uniform diameter in the range of 50 nm. It is the only permeability barrier between blood and coelomic fluid.     

Familial Mediterranean Fever: Recent Advances in Pathogenesis and Management

The success of colchicine therapy in the management of familial Mediterranean fever has provided new direction to investigations into the pathogenesis of this disease. Examination of HLA antigen frequencies in 53 patients with familial Mediterranean fever and appropriate controls, as well as various immunologic studies have yielded no significant differences. However, B lymphocyte typing and assays for immune complexes, lymphokines and prostaglandins may be of potential interest. Preliminary studies indicate that leukocytes of patients with familial Mediterranean fever release increased amounts of lysozyme (P<0.01), when subjected to high temperatures, and of both lysozyme and myeloperoxidase at low osmotic concentrations. The known and potential effects of colchicine on leukocyte and cellular metabolism, and the current status of colchicine prophylaxis are reviewed. In patients receiving an optimum colchicine dose of 1.5 to 1.8 mg per day, side effects have been minimal and the frequency of attacks has been decreased significantly.     

Influence of adrenergic antagonists and apomorphine on prolactin release induced by serotonergic antagonists in the monkey.

The influence of adrenergic receptor blockers on the prolactin releasing effect of methysergide and cyproheptadine was examined in sexually mature female monkeys under ketamine anesthesia. Propranolol, a β-adrenergic blocker, at a dose of 1 mg/kg did not alter the prolactin releasing action of 0.1 mg/kg of methysergide but significantly potentiated (P < 0.025) the prolactin releasing action of 0.5 mg/kg of cyproheptadine. Phentolamine and phenoxybenzamine, both α-adrenergic blockers, at 1 mg/kg blunted the prolactin releasing effect of methysergide and cyproheptadine, but the pattern of prolactin blockade was different between the two putative antiserotonergic drugs. The prior administration of apomorphine, 4 mg/kg, a dopamine receptor stimulator, blocked the prolactin releasing effect of methysergide and cyproheptadine. Evidence presented here and from the literature indicate that the prolactin releasing action of methysergide and cyproheptadine is mediated by an antidopaminergic action directly on the pituitary.     

Transfer of cultured bovine embryos

A total of 126 bovine embryos were surgically collected from 16 superovulated donor heifers 5 days after estrus and randomly selected for either immediate transfer to synchronized recipients or $\text{in}$$\text{vitro}$ culture at 37°C for 24 hours and subsequent transfer. Twenty-four of 56 (42.8%) embryos maintained for 24 hours in Ham's F10 medium supplemented with 10% heat treated fetal calf serum (HTFCS) and transferred to 32 recipients produced live calves. Survival of 70 noncultured embryos transferred to 35 recipients was 55.7% (39 calves). The percentages of recipients that were diagnosed pregnant at 42 days with cultured and control embryos were 59.4% ($\text{19}\text{32}$) and 74.3% ($\text{26}\text{35}$), respectively. No statistical difference was observed between the $\text{in}$$\text{vitro}$ cultured and control embryos for viability following transfer to recipient females.In a second study, Day 7 embryos maintained in Ham's F10 medium supplemented with 10% HTFC serum for various culture periods were tested for viability following nonsurgical transfer to recipient females. A total of $\text{1}\text{5}$, $\text{1}\text{3}$ and $\text{0}\text{4}$ embryos cultured for 24, 48 and 72 hours, respectively, resulted in pregnant recipients following transfer.     

Studies on the subcellular localization and role of glutathione-insulin transhydrogenase in rat liver

₁₂₅I-insulin was shown to be internalized in vivo to a discrete population of low-density membranes (ligandosomes), distinct from the Golgi, endoplasmic reticulum, plasma membrane, and lysosomes. However, analytical subcellular fractionation shows that glutathione-insulin transhydrogenase is localized to the endoplasmic reticulum. Measurement of the specific enzyme activity of glutathione-insulin transhydrogenase showed no differences between normal, diabetic, and hyperinsulinaemic rats. These results suggest that glutathione-insulin transhydrogenase is not directly involved in the subceltular processing of receptor-bound internalized insulin.     

On the correlation between the activity of ATP-hydrolase and the kinetics of the flash-induced P515 electrochromic bandshift in spinach chloroplasts

The P515 absorbance change upon single-turnover light flashes has been studied in intact leaves and isolated chloroplasts from spinach. A comparative study of the effects of preillumination on the kinetics of the P515 response and on the activity of the chloroplast ATPase has been made. The slow component (reaction 2) in the flash-induced P515 response normally present in dark-adapted chloroplasts is reduced or even absent under conditions in which the ATPase is activated by preillumination. This suppression of reaction 2 appeared to be temporary in leaves and chloroplasts; its duration in chloroplasts is shown to be dependent on the amount of ATP present. Tentoxin inhibits the preillumination-dependent suppression of reaction 2.