Development of the articular cavity in the rat temporomandibular joint with special reference to the behavior of endothelial cells and macrophages

Previous developmental studies on the temporomandibular joint (TMJ) have proposed several hypotheses on the formation of its articular cavity. However, detailed information is meager. The present study examined the formation process of the articular cavity in the rat TMJ by immunocytochemistry for CD31, RECA-1, and ED1, which are useful cellular markers for endothelial cells and monocyte/macrophage lineages, respectively. The upper articular cavity formation had begun by embryonic day 21 (E21) and was completed at postnatal day 1 (P1) in advance of the lower cavitation; the latter took place from P1 to P3. The occurrence and distribution pattern of the CD31-, RECA-1-, and ED1-positive cells differed between the upper and lower articular cavity-forming areas: the ED1-positive cells exclusively occurred in the area of the prospective upper articular cavity prior to its formation, while no ED1-positive cell appeared in the lower cavity-forming area. In contrast, the CD31- and RECA-1-positive endothelial cells were restricted to the lower cavity-forming area (never the prospective upper cavity) at E19 and diminished thereafter. Throughout the cavity formation, we failed to find any apoptotic cells in the cavity formation area, indicating no involvement of apoptosis in the cavity formation in TMJ. The present findings on the behaviors of endothelial cells and ED1-positive cells show a possibility of different mechanism in the cavity formation between the upper and lower articular cavities in the rat TMJ. The appearance of ED1-reactive cells and temporal vascularization may play crucial roles in the upper and lower articular cavity formation, respectively.     

Present status and tasks for future of point of care testing

This paper introduces Point-Of-Care Testing(POCT) developed by Bayer, mainly focusing on urine dipstick and tests for Diabetes Mellitus. Urinalysis using a dipstick has been widely carried out as a screening test for various kinds of diseases. Ten-pad urine dipstick is commercially available at the present time, and the desktop instruments have been developed for automatic optical reading, such as the Clinitek 50/100/500 systems. More recently, Bayer developed a new urine dipstick intended for reliable detection of the early stage of kidney disease without the influence of urine condensation or dilution. The dipstick adds 2 pads to conventional urine dipsticks: one for the measurement of small amounts of protein(albumin), and the other for creatinine. A semi-quantitative urine protein-to-creatinine ratio is based on these results. There have been significant advances made in blood glucose meters for POCT in terms of reliability, simplicity of operation, sample volume, etc. And not only healthcare professionals but also patients with diabetes have used POCT meters. Dexter-ZII is available as one of these meters. DCA2000 is a portable analyzer for measuring HbA1c in 6 min. Patients could be treated and instructed on the basis of HbA1c measured by DCA2000. As one of the tasks for the future, it is preferable that some POCT systems be available as OTC for ordinary people to manage their own health. Also, I emphasize that it is important to review the usability of conventional urine dipsticks like a check for drug side effects, as well as for developing new urine analyses.     

Results of animal experiments using an undulation pump total artificial heart: analysis of 10 day and 19 day survival

An undulation pump is a special rotary blood pump in which rotation of a brushless DC motor is transformed to an undulating motion by a disc in the pump housing attached by means of a special link mechanism. In the blood pump, a closed line between the disc and housing moves from the inlet to the outlet by this undulating disc motion, which sucks and pushes the blood from the inlet to the outlet. Because the same phenomena occurs at both sides of the disc, a continuous flow is obtained when the motor rotational speed is constant. The pump flow pattern can be easily changed from continuous flow to pulsatile flow by controlling the motor drive current pattern. A seal membrane made of segmented polyurethane protects the blood from invading the link mechanism as well as the motor. UPTAH is fabricated with two undulation pumps and two brushless DC motors. Its size is 75 mm in diameter and 80 mm long, and it has one of the great advantage of no compliance chamber required in the system. UPTAHs were implanted under cardiopulmonary bypass (CPB) into the chest cavities of 16 goats, each weighing between 41 and 72 kg. No anticoagulant and antiplatelet agent was used after the surgery. The left atrial pressure was automatically controlled to prevent its elevation and sucking of the atrial wall into the atrial cuff. The following results were obtained: (1) UPTAHs fit well into all the goats; (2) the longest survival was 19.8 days, the cause of death was bleeding from the aortic anastomosis; (3) No thrombus was observed in the blood pump despite no anticoagulant use. Hemolysis depended upon the length of CPB during surgery. When CPB time was within 2 hours, hemolysis level returned to baseline within a few days of the surgery. UPTAH is a promising implantable TAH, because of its small size and easy controllability.     

Benzylpenicillin preparations can evoke a systemic anaphylactic reaction in guinea pigs

All of the five commercially available benzylpenicillin preparations obtained from different sources and a PcG preparation prepared by filtration of a commercial PcG on Sephadex G10 elicited the systemic anaphylactic reactions in guinea pigs which had been immunized with benzylpenicilloyl (BPO)-Ascaris extract conjugate (BPO-As) mixed with aluminum hydroxide gel. These preparations could evoke no such reactions in guinea pigs immunized with BPO-bovine gamma globulin conjugate (BPO-BGG) emulsified with complete Freund's adjuvant. The severity of the systemic anaphylactic reactions correlated significantly with the titers of either 8-day passive cutaneous anaphylactic (8-day PCA) reactions or 4-hr PCA reactions evoked with the same benzylpenicillin preparations. In vitro benzylpenicillin preparation contracted the tracheas of the guinea pigs immunized with BPO-As. These results indicated that the commercially available benzylpenicillin preparations have enough antigenicity to evoke systemic anaphylactic reactions in guinea pigs immunized with BPO-As mixed with aluminum hydroxide gel. Such guinea pigs represent an animal model for investigation of penicillin allergy.     

Cloning and nucleotide sequence of the gene encoding arginine deiminase of Mycoplasma arginini.

The existence of a mycoplasmal arginine deiminase which catalyzes the conversion of L-arginine to L-citrulline has been postulated. Here we show the partial amino acid sequence of arginine deiminase of Mycoplasma arginini and the complete nucleotide sequence of the arginine deiminase gene of M. arginini. The open reading frame deduced from this sequence consists of 1,230 bp encoding 410 amino acids. The mature form of this enzyme contains 409 amino acids after the deletion of the first methionine. In this open reading frame, TGA nonsense codons are used as tryptophan codons; this usage was verified by determination of the amino acid sequence. The molecular weight of the enzyme calculated from the deduced amino acid sequence is 46,372. Recently, the nucleotide sequence of the arginine deiminase gene of M. arginini was reported by Kondo et al. (K. Kondo, H. Sone, H. Yoshida, T. Toida, K. Kanatani, Y.-M. Hong N. Nishino, and J. Tanaka, Mol. Gen. Genet. 221:81-86, 1990). However, their sequence differed from ours in several places and especially at the C terminus.     

Hemolymph lectin of the pearl oyster, Pinctada fucata martensii: a possible non-self recognition system

To elucidate a mutual correlation between the hemolymph lectin and hemocytes of the pearl oyster, Pinctada fucata martensii, we searched for common epitopes and ligands. Neither the hemocyte plasma membrane nor cytoplasm was immunoreactive to anti-hemolymph lectin antibody. The hemolymph lectin strongly bound to D-galactose and N-acetyl-D-galactosamine, and the plasma membrane of both granulocytes and agranulocytes had affinity only for D-mannose and N-acetyl-D-glucosamine-binding plant lectins. In the gonad, the hemolymph lectin selectively adsorbed injected horse red blood cells (HRBC), and its hemagglutinating activity probably prevented them from dispersing. Pinctada sp. may possess system of recognition of non-self by the hemolymph lectin.     

Genetic polymorphisms of orosomucoid and alpha-2-HS-glycoprotein in Thai,Sri Lankan and Paraguayan populations

The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1 ^* 15 in Thai,ORM1 ^* 16 in Paraguayan,ORM2 ^* 21 andORM2 ^* 22 in Sri Lankan.