A 2.6-GByte/s multipurpose chip-to-chip interface

A 2.6 GByte/s megacell that interfaces to single or double byte wide DRAMs or logic chips is implemented using 0.35-0.18 μm CMOS technologies. Special I/O circuits are used to guarantee 800 Mbit/s/pin data rate. Microwave PC board design methodologies are used to achieve the maximum possible interconnect bandwidth     

Reductive cleavage of the disulfide bonds of the collagen IV noncollagenous domain in aqueous sodium dodecyl sulfate: absence of intermolecular nondisulfide cross-links

OBJECTIVES: The goal of this study was to develop an accurate, simplified proximal isovelocity surface area (PISA) method for calculating volume flow rate using lower blue-red interface velocity produced by a color Doppler zero baseline shift technique. BACKGROUND: The Doppler color proximal isovelocity surface area method has been shown to be accurate for calculating the volume flow rate (Q) across a narrowed orifice by the formula Q = PISA x Blue-red interface velocity. A hemispheric model is generally used to calculate proximal isovelocity surface area (PISA = 2 pi a2, where a = the radius corresponding to the blue-red interface velocity). Although a hemispheric model is simple, requiring measurement of one radius, it may underestimate the actual volume flow rate because, in the general case, the shape of a proximal isovelocity surface area is hemielliptic. Although a hemielliptic model is generally more accurate for calculating proximal isovelocity surface area, it is more complex, requiring measurement of two orthogonal radii. METHODS: Sixteen in vitro constant flow model studies were performed using planar circular orifices (diameter range 6 to 16 mm). The blue-red interface velocity was changed from 3 to 54 cm/s using color Doppler zero baseline shift. RESULTS: 1) With decreasing blue-red interface velocity, the size of the proximal isovelocity surface area was increased, and its shape changed from hemielliptic to hemispheric. 2) With the blue-red interface velocity in the range 11 to 15 cm/s, the proximal isovelocity surface area became nearly hemispheric; however, it was difficult to determine the blue-red interface radius at a blue-red interface velocity < 10 cm/s because of interface fluctuations. 3) Calculated volume flow rate using the hemispheric proximal isovelocity surface area model with a single radius was relatively accurate at a blue-red interface velocity of 11 to 15 cm/s (mean percent difference from actual volume flow rate was -3.6%). CONCLUSIONS: Because the shape of the proximal isovelocity surface area is nearly hemispheric at a blue-red interface velocity of 11 to 15 cm/s, volume flow rate can be accurately calculated in this proximal isovelocity surface area interface velocity range (produced by zero baseline shift) by measuring a single-interface radius. This approach should be clinically useful for calculating the volume flow rate across stenotic and regurgitant valves and across shunt defects.     

Tissue response to nano-hydroxyapatite/collagen composite implants in marrow cavity

The formation of otoconia in the endolymphatic sac (ES) of the larval newt, Cynops pyrrhogaster, has been studied by light and transmission electron microscopy. Some of the epithelial cells of the ES contain an abundance of swollen vesicles, Golgi complexes, rough endoplasmic reticula and ribosomes at the late larval stages 50 and 51, approximately 26-30 days after eggs are laid. Five days later, at stage 52, crystals are present in the vacuoles between the epithelial cells. Serial sections indicate that these vacuoles actually form small canals which lie in the wall and join the lumen of the ES. Reconstruction of the ES shows that several canals are contained in the ES wall. At stage 56, about 72 days after eggs are laid, a large number of otoconia are present in the ES lumen, while the otoconia disappear from the canals. It appears that the otoconia are first produced in the canals and then released to the lumen. Some epithelial cells of the ES are thought to expel the organic and inorganic material to the canals to form the otoconia in situ. The process of formation of the otoconia in the ES is discussed.     

Polycarboxylates in soda ash detergents

Calcium carbonate deposition on cotton fabric from soda ash-based detergents containing polycarboxylates is measured and related to polymer composition and molecular weight, under varying conditions of temperature, water hardness and detergent composition. Deposition effects on fabric are compared with threshold inhibition effects and calcium binding capacities of the polymers. Polyacrylic acids with molecular weights of 2000–5000 are most effective in preventing calcium carbonate deposition on fabric. A 1.5:1 acrylic acid:maleic acid copolymer is more effective than polyacrylic acid. Detergents with LAS left somewhat higher calcium carbonate deposits than detergents with a nonionic surfactant. Prevention of visible calcium carbonate precipitation in the absence of fabric (“threshold effects”) appears at polymer levels considerably lower than those necessary to prevent calcium carbonate deposition on fabric. Deposition on fabric can be prevented at levels of polymer much less than that necessary to bind most of the calcium ions, as determined by the calcium binding capacity. Presented at the AOCS meeting in New Orleans in May 1987.     

Synaptojanin 1: localization on coated endocytic intermediates in nerve terminals and interaction of its 170 kDa isoform with Eps15

This investigation characterized the smooth muscle relaxing effect of a novel nitric oxide (NO)-releasing substance, GEA 3175 (1,2,3,4-oxatriazolium, 3-(3-chloro-2-methylphenyl)-5-[[(4-methylphenyl)sulfonyl]amino], hydroxide inner salt) on guinea-pig trachea. GEA 3175 caused a concentration-dependent relaxation of tracheal smooth muscle precontracted with acetylcholine. This effect was reversed by both okadaic acid, an inhibitor of serine/threonine-specific phosphatases, and iberiotoxin, an inhibitor of Ca2+-activated K+ channels. Furthermore, GEA 3175 had a relaxation potency similar to that of the commonly used NO-donor, S-nitroso-N-acetyl-penicillamine. On the contractile response provoked by electrical field stimulation, GEA 3175 induced a long-lasting relaxation which persisted even after repeated washing. The relaxing effect of GEA 3175 was associated with rises in guanosine 3':5'-cyclic monophosphate (cGMP). In time course studies, cGMP continued to increase with incubation time after stimulation with GEA 3175 and there was a significant elevation of cGMP even after washing. In contrast, incubation with S-nitroso-N-acetyl-penicillamine caused a transient rise in cGMP. The present investigation showed that GEA 3175 evokes long-lasting effects on contractile responses and cGMP levels in guinea-pig trachea. Our results indicate that the relaxing effect of GEA 3175 occurs through a mechanism involving phosphatases and iberiotoxin-sensitive K+ channels.     

Sex differences in nitrite/nitrate levels and antioxidant defense in rat brain

This study assessed sex differences in stable metabolites of nitric oxide and major enzymes involved in antioxidant defense in various regions of rat brain. Nitrite/nitrate levels and activities of superoxide dismutase and catalase were determined in cortex, hippocampus, corpus striatum, midbrain and cerebellum of adult male and female Sprague-Dawley rats. Nitrite/nitrate levels were significantly higher in the cortex and the hippocampus of male than female rats, while catalase activity was higher in the cortex of females than in males. These sex differences may have significant effects on brain function in health and disease.     

Phase II and pharmacologic study of topotecan administered as a 21-day continuous infusion to patients with colorectal cancer

PURPOSE: Topotecan is a specific inhibitor of topoisomerase I. Preclinical data have indicated that topoisomerase I inhibitors demonstrate more efficacy and have a greater therapeutic index with prolonged continuous exposure. The feasibility of this concept in humans using a 21-day continuous infusion of topotecan has been reported. We conducted a phase II study of this 21-day continuous topotecan administration schedule in patients with locally advanced, unresectable or metastatic colorectal cancer. PATIENTS AND METHODS: Topotecan, initially applied at a dose of 0.6 mg/m2/d, was administered as a continuous infusion via an ambulatory pump for 21 days repeated every 4 weeks. The starting dose was reduced to 0.5 mg/m2/d, because in five of the first 11 patients, the second course had to be delayed due to prolonged myelosuppression. Forty-two patients entered the study; one patient was ineligible and was excluded from further analyses. RESULTS: The overall response rate was 10%, with one complete and three partial responses. The median response duration was 7 months (range, 4 to 11). With this schedule, the major toxicity was prolonged cumulative myelosuppression, including a marked inhibition of erythropoiesis. A total transfusion of 250 U of erythrocytes was needed to maintain a hemoglobin level greater than 6.0 mmol/L. Other side effects were mild, and included alopecia (47%), periodic nausea (40%)/vomiting (22%), and fatigue (16%). Pharmacokinetic evaluation showed a mean steady-state plasma concentration (Css) of topotecan of 0.62 ng/mL (range, 0.33 to 1.1), with a significant relationship between the Css of topotecan and common cytotoxicity criteria (CTC) grade of leukocytopenia. CONCLUSION: Topotecan administered as a 21-day continuous infusion exerts minor activity as single-agent therapy in patients with metastatic colorectal cancer.