半浆血临床应用和质量的初步调查分析

随着医学和输血学的发展,成分输血已成为当今输血技术发展的总趋势.国内各种血液成分的试制和临床应用都取得了良好的效果,其血液成分输注占输全血的20～40%,半浆血因含原全血中血浆的一部分,临床输注通畅,费用低,抽出的部分血浆可供肝硬化、烧伤、肝炎等病人输用或供制备血浆蛋白制品,

ASSOCIATION OF PLASMA HOMOCYSTEINE LEVEL AND N^5, N^(10) -METHYLENETETRAHYDROFOLATE REDUCTASE GENE POLYMORPHISM WITH CEREBRAL INFARCTION

Objective. To investigate the relationship of plasma homocysteine (Hcy) level to stroke and genetic factor to elevated plasma Hcy level.Methods. The plasma Hcy level was measured by capillary electrophoresis- ultraviolet detection and the gene polymorphism of N5, N10 - methylenetetrahydrofolate reductase (MTHFR) was studied with PCR - RFLP assay in 43 patients with cortical cerebral infarction and 42 healthy controls.Results. The plasma Hcy level of the patients ( 19. 3 + 6. 0 μ mol/L) was markedly higher than that of the controls (13.7 + 5.4 μ mol/L) ( t = 4. 16, P ＜ 0. 001). There are 3 genotypes, C/C, C/T and T/T, about base - variation of MTHFR gene at locus 677. The plasma Hcy level of the subjects with T/T genotype was higher than that of subjects with other genotypes. However, the frequencies of each genotype and allele were not significantly different between the patients and the controls.Conclusions. The elevated plasma Hcy level is a risk factor for atherothrombotic cerebral infarction, and is related to the C→T mutation at locus 677 of MTHFR gene.

Plasma homocysteine levels are independently associated with alterations of large artery stiffness in men but not in women

Objectives To investigate the associations of the plasma homocysteine levels with the alterations in arterial stiffness in a commu- nity-based cohort. The gender differences in these associations were examined. Methods We evaluated the relationship between plasma homocysteine levels to three measures of vascular ftmction [carotid-femoral pulse wave velocity （CF-PWV）, carotid-ankle PWV （CA-PWV） and heart rate corrected augmentation index （AI）] in 1680 participants （mean age： 61.5 years; 709 men, 971 women） from communities of Beijing, China. Results In univariate analysis, plasma homocysteine levels was positively related to the CF-PWV （r = 0.211, P 〈 0.0001） and CA-PWV （r = 0.148, P 〈 0.0001）, whereas inversely associated with AI （r = -0.052, P = 0.016）. In multiple linear regression models adjusting for covariants, plasma homocysteine remained positively related to the CF-PWV （standardized 13 = 0.065, P = 0.007） in total cases. When the groups of men and women were examined separately, plasma homocysteine remained positively associated with the CF-PWV （standardized β = 0.082, P = 0.023） in men, whereas the relations between homocysteine and any of the arterial stiffness indices were not further present in women. Conclusions In Chinese population, plasma homocysteine levels are independently associated with alterations of large artery stiffness in men but not in women.

Effect of B vitamin supplementation on plasma homocysteine levels in celiac disease

AIM: To investigate the effect of vitamin supplements on homocysteine levels in patients with celiac disease. METHODS: Vitamin B6, folate, vitamin B12, and fasting plasma homocysteine levels were measured in 51 consecutive adults with celiac disease [median (range) age 56 (18-63) years; 40% men, 26 (51%) had villous atrophy, and 25 (49%) used B-vitamin supplements] and 50 healthy control individuals matched for age and sex. Finally, the C677T polymorphism of 5,10-methylene tetrahydrofolate reductase (MTHFR) was evaluated in 46 patients with celiac disease and all control individuals. RESULTS: Patients with celiac disease and using vitamin supplements had higher serum vitamin B6 (P = 0.003),folate (P < 0.001), and vitamin B12 (P = 0.012) levels than patients who did not or healthy controls (P = 0.035, P < 0.001, P = 0.007, for vitamin B6, folate, and vitamin B12, respectively). Lower plasma homocysteine levels were found in patients using vitamin supplements than in patients who did not (P = 0.001) or healthy controls (P = 0.003). However, vitamin B6 and folate, not vitamin B12, were significantly and independently associated with homocysteine levels. Twenty-four (48%) of 50 controls and 23 (50%) of 46 patients with celiac disease carried the MTHFR thermolabile variant T-allele (P = 0.89). CONCLUSION: Homocysteine levels are dependent on Marsh classification and the regular use of B-vitamin supplements is effective in reduction of homocysteine levels in patients with celiac disease and should be considered in disease management.

Changes in Plasma Osmolality, Cortisol and Amino Acid Levels of Tongue Sole(Cynoglossus semilaevis) at Different Salinities

A serial of salinity transferring treatments were performed to investigate the osmoregulation of tongue sole(Cynoglossus semilaevis). Juvenile tongue sole were directly transferred from a salinity of 30 to 0, 10, 20, 30, 40 and 50. Blood sampling was performed for each treatment after 0, 1, 6 and 12 h, as well as after 1, 2, 4, 8, 16 and 32 d. The plasma osmolality, cortisol and free amino acids were assessed. Under the experimental conditions, no fish died after acute salinity transfer. The plasma cortisol level increased 1 h after the abrupt transfer from a salinity of 30 to that of 0, 40 and 50, and decreased from 6 h to 8 d after transfer. Similar trends were observed in the changes of plasma osmolality. The plasma free amino acids concentration showed a ‘U-shaped' relationship with salinity after being transferred to different salinities for 4 days. More obvious changes of plasma free amino acid concentration occurred under hyper-osmotic conditions than under hypo-osmotic conditions. The concentrations of valine, isoleucine, lysine, glutamic acid, glycine, proline and taurine increased with rising salinity. The plasma levels of threonine, leucine, arginine, serine, and alanine showed a ‘U-shaped' relationship with salinity. The results of this study suggested that free amino acids might have important effects on osmotic acclimation in tongue sole.

Modification at Lys24 with fatty acid generates active calcitonin gene-related peptide with much improved plasma stability

As a 37-amino acid vasoactive neuropeptide, calcitonin gene-related peptide （CGRP） is widely distributed in nervous systems. The studies and clinical applications of CGRP are limited by its peptide nature and short half-life. A series of peptide analogues of the α-form of CGRP were synthesized. Afterwards, by using in vitro metabolic and activity studies, we prepared two high affinity analogues with significantly improved plasma stability.

Effect of Critical Beam Radius on Self-focusing of cosh-Gaussian Laser Beams in Collisionless Magnetized Plasma

Effect of critical beam radius on self-focusing of cosh-Gaussian laser beams in collisionless magnetized plasma under ponderomotive nonlinearity forms the main core of present work. To investigate propagation dynamics of cosh-Gaussian laser beams in collisionless magnetized plasma, well established parabolic equation approach under WKB and paraxial approximations is employed. Our study is crucially pivoted on the concept of critical curve and subsequent determination of numerical interval for decentered parameter to sustain the competition between diffraction and self-focusing during the propagation of laser beam. Additionally, in the present study an interesting feature in the self-focusing region of the critical curve has been attempted for different values of decentered parameter.

Enhanced plasma factor Ⅷ activity in mice via cysteine mutation using dual vectors

Hemophilia A is caused by a genetic mutation in coagulation factor VIII （FVIII） gene and gene therapy is considered to be a promising strategy for its treatment. We recently demonstrated that co-delivery of two vectors expressing M662C mutated heavy and D1828C mutated light chain genes of B-domain-deleted coagulation factor VIII （BDD-FVIII） leads to inter-chain disulfide cross-linking and improved heavy chain secretion in vitro. In this study, co-injection of both M662C and D1828C mutated BDD-FVIII gene expression vectors into mice resulted in increased heavy chain secretion and coagulation activity in plasma in vivo. Approximately （239＋_56） ng mL-1 above endogenous levels of transgenic FVIII heavy chain was found in mouse plasma using a chain-specific ELISA. For FVIII coagulation activity, approximately （1.09＋_0.25） IU mL-1 above en- dogenous levels were detected in co-injected transgenic mouse plasma using a chromogenic assay. These data demonstrate that inter-chain disulfide bonds likely increase heavy chain secretion and coagulation activity in the plasma of transgenic mice with an improved efficacy of a dual-vector delivery of BDD-FVIII gene. These findings support our ongoing efforts to develop a gene therapy for hemophilia A treatment using dual-AAV vectors.