Photodynamic therapy of tumours in gastroenterology—a review

Photodynamic therapy (PDT) is the local destruction of tissue by the interaction of light with a previously administered photosensitizer producing a photochemical effect. This technique has been demonstrated to permit the eradication of small tumours in experimental and clinical practice, with clear biological advantages. This paper reviews PDT experience in gastroenterology, together with concepts currently under experimental investigation.     

血管细胞粘附分子调控造血的研究进展

本文简述了血管细胞粘附分子 (Vascularcelladhesionmolecule 1,VCAM 1)的结构和生物学功能 ,总结了VCAM 1在恶性血液病骨髓基质中的表达和意义 ,探讨了VCAM 1在造血干细胞动员和归巢中的作用 ,指出VCAM 1作用机制的深入研究将对恶性血液病的治疗提供更为有效的方法。     

The relationship between ATP hydrolysis and active force in compressed and swollen skinned muscle fibers of the rabbit

We investigated whether the inhibition of force generation observed in compressed muscle fibers is accompanied by a coupled reduction in hydrolytic activity. Isometric force and rates of ATP hydrolysis (ATPase) were measured as functions of the relative width of chemically skinned skeletal muscle fiber segments immersed in relaxing (pCa>8) and activating (pCa 4.9) salt solutions. Osmotic radial compression of the fiber segment was produced (with little or no affect on striation spacing) by adding Dextran T500 to the bathing media. ADP as a product of ATP hydrolysis in fibers undergoing 10–15 min contractions was measured using high pressure liquid chromatography. Compression of the (initially swollen) fiber segment with dextran produced a slight (4%) increase in average active force and then, with further compression, a sharp decrease (with maximum around in situ width). With compression, the average ATPase of the fiber decreased monotonically, and with extreme compression (with 0.22 g dextran per ml), ATPase fell to a fifth of its level determined in dextran-free solution while force was abolished. The time course of active force development was described by the sum of two exponential functions, the faster of which characterized the rate of rise. Fiber compression (0.14 g dextran per ml) reduced the rate of rise of force ten-fold compared to that in dextran-free solution. Hindrance of cross movement is proposed to account for the inhibition of active force generation and (coupled) ATPase in compressed fibers.     

Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa

Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.      

Current trends in the integration and reimbursement of complementary and alternative medicine by managed care, insurance carriers, and hospital providers

OBJECTIVES: To assess the status of managed care and insurance coverage of complementary and alternative medicine (CAM) and the integration of such services offered by hospitals. METHODS: A literature review and information search was conducted to determine which insurers had special policies for CAM and which hospitals were offering CAM. Telephone interviews were conducted with a definitive sample of 18 insurers and a representative subsample of seven hospitals. RESULTS: A majority of the insurers interviewed offered some coverage for the following: nutrition counseling, biofeedback, psychotherapy, acupuncture, preventive medicine, chiropractic, osteopathy, and physical therapy. Twelve insurers said that market demand was their primary motivation for covering CAM. Factors determining whether insurers would offer coverage for additional therapies included potential cost-effectiveness based on consumer interest, demonstrable clinical efficacy, and state mandates. Some hospitals are also responding to consumer interest in CAM, although hospitals can only offer CAM therapies for which local, licensed practitioners are available. Among the most common obstacles listed to incorporating CAM into mainstream health care were lack of research on efficacy, economics, ignorance about CAM, provider competition and division, and lack of standards of practice. CONCLUSIONS: Consumer demand for CAM is motivating more insurers and hospitals to assess the benefits of incorporating CAM. Outcomes studies for both allopathic and CAM therapies are needed to help create a health care system based upon treatments that work, whether they are mainstream, complementary, or alternative.     

Response from lieberman and colleagues

Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165