Purification and chemical modification of porcine bone morphogenetic protein

Implantation of porcine bone morphogenetic protein (pBMP) in the muscle induces differentiation of mesenchymal-type cells and results in endochondral bone formation. pBMP was isolated from porcine demineralized bone matrix and purified by hydroxyapatite chromatography, Sephadex G75 gel filtration, preparative sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), preparative isoelectric focusing (IEF), and chromatofocusing fast protein liquid chromatography (FPLC). Porcine BMP has an MW of 26 K and a range of pI from 4.65 to 4.73 determined by SDS-PAGE and IEF, respectively. Reconstitution with the citrate buffer supernatant fraction enables as little as 50 micrograms of the soluble pBMP fractions to induce osteogenesis in an in vivo assay. Chemical modification studies indicate that the osteoinductive potential of the pBMP molecule depends on tyrosine, carboxyl groups, and disulfide bonds and can be increased by modification of sulfhydryl groups. Modification of arginine and tryptophan has no effect on bioactivity. By pepsin-limited proteolysis, fragments of pBMP with an MW of 6-14 K show definite, although reduced, BMP activity.     

Microvascular corrosion casting of normal tissue, transitional mucosa and adenocarcinoma in the human colon.

The microcirculatory architecture of normal tissue, transitional mucosa and adenocarcinoma of the human colon was investigated with microvascular corrosion casting (MVCC) combined with scanning electron microscopy (SEM). The study showed that the capillaries within the normal mucosa were arranged in a regular hexagonal pattern around the mucosal glands and that the microvessels of transitional mucosa mostly had lost the typical hexagonal pattern and become slightly wider in diameter. The microvessels in the tumor periphery were increased in number and disorganized, and presented large variation in morphology with claw-like formations, widened sinuses, diverticula and appendixoid patterns. Microvessels were lacking in the central areas of tumors. These morphological alterations may serve as additional indicators of tumor development.     

The Intubation Difficulty Scale (IDS): Proposal and Evaluation of a New Score Characterizing the Complexity of Endotracheal Intubation

Background: A quantitative scale of intubation difficulty would be useful for objectively comparing the complexity of endotracheal intubations. The authors have developed a quantitative score that can be used to evaluate intubating conditions and techniques with the aim of determining the relative values predictive factors of intubation difficulty and of the techniques used to decrease such difficulties.

Methods: An Intubation Difficulty Scale (IDS) was developed, based on parameters known to be associated with difficult intubation. It was then evaluated prospectively in a group of 311 consecutive prehospital intubations and 315 intubations in an operating room. In the operating room, the IDS was compared with two other parameters: the time to completion of intubation and the visual analog scale (VAS). Time was measured by an independent observer. Operators in both groups completed a checklist regarding the conditions of intubation.

Results: There is a good correlation between the IDS scale and the VAS assessment of difficulty and time to completion of intubation. VAS and time to completion have a significant but lesser correlation to each other. Comparison of IDS with operator-assessed subjective categorical impression of difficulty by Kruskall-Wallis was statistically significant.     

A study on plasma norepinephrine and epinephrine levels in TCM liver syndromes.

The levels of plasma norepinephrine (NE) and epinephrine (E) were determined by HPLC in 220 patients with various TCM liver syndromes, and in 96 healthy subjects as controls. The plasma NE and E contents were higher in patients with liver excess syndromes, including Ganqi Yujie (GQYJ [symbol: see text]) syndrome, Ganyang Shangkang (GYSK [symbol: see text]) syndrome, Ganhuo Shangyan (GHSY [symbol: see text]) syndrome, and Ganyang Huafeng (GYHF [symbol: see text]) syndrome; while they were lower in patients with liver deficiency syndromes, including Ganqixu (GQX [symbol: see text]) syndrome, Ganxuexu (GXX [symbol: see text]) syndrome, and Ganyinxu (GYX [symbol: see text]) syndrome. Futhermore, when Ganshen Yinxu (GSYX [symbol: see text]) syndrome was turned into GYSK and then into GYHF, the plasma NE and E contents increased in order of precedence; while when GQYJ was turned into Ganyu Pixu (GYPX [symbol: see text]) syndrome, both NE and E contents decreased. The results suggest that the plasma NE and E contents are reliable objective parameters for the study of pathophysiological basis of the liver excess and liver deficiency syndromes, and the liver-kidney and liver-spleen interrelated syndromes.     

Consequences of foot binding among older women in Beijing, China.

OBJECTIVES: This study examined the prevalence and consequences of foot binding in older Chinese women. METHODS: Women older than 70 years in Beijing, China, were assessed for bound feet, falls, functional status, and bone density. RESULTS: Thirty-eight percent of women aged 80 years and older and 18% of women aged 70 through 79 years had bound-foot deformities. Women with bound feet were more likely to fall, less able to squat, and less able to stand up from a chair without assistance than women with normal feet. They also had 14.3% less functional reach (a test of balance) and 5.1% lower hip bone density. CONCLUSIONS: Foot binding has caused substantial disability that is still evident in many elderly Chinese women.     

Different effects of intracellular and extracellular TEA on voltage-dependent K currents of acutely isolated hippocampal CA1 neurons.

Tetraethylammonium (TEA) effects on K currents were examined on either side of the membrane of hippocampal CA1 neurons by means of whole-cell voltage-clamp recording and intracellular perfusion. Recording media contained ion channel blockers to allow the selective activation of voltage-dependent K currents which consisted of a rapidly decaying component (A-current) and a delayed component. Voltage protocols were applied to separate the A-current from the delayed component. Results show that 10 mM extracellular TEA suppressed 50 +/- 11% (S.D., n = 4) of the delayed current at different levels of depolarization but had little effect on the A-current. In contrast 10 mM TEA applied by intracellular perfusion suppressed the A-current by 42 +/- 10% (S.D., n = 4) in addition to inhibiting the delayed currently 55 +/- 15% (S.D., n = 4). Both the intracellular and extracellular actions of TEA on K currents showed no voltage- nor time-dependency. The results suggest that voltage-dependent transient current (A-current) is mediated through a separate group of ionic channels distinct from those that sustained the delayed current. Furthermore, the asymmetrical effects of intracellular and extracellular TEA on the transient current are similar to those described for the A-current in molluscan neurons. This observation supports the notion that the structure of the ion channel mediating the A-current is closely conserved across different species.