Objective To investigate the serum levels of vitamin B12 and folic acid (FA) of exudative agerelated macular degeneration (AMD).Methods A total of 84 patients with exudative AMD（AMD group）and 78 patients with non-exudative AMD （control group） diagnosed at Xijing Hospital between June 2008 and September 2009 were assessed in this study. Serum vitamin B12 and FA levels were measured by chemiluminescence immunoassay. The statistical information of epidemiology and risk factors exposure histories were collected and compared.Results AMD group had significantly lower serum vitamin B12 levels ［（247.51plusmn;93.92）ng/ml］ compared with the control group ［（312.52plusmn;143.08） ng/ml］，the difference was statistical significance (t=5.013, P＜0.001). Serum FA levels in AMD group ［（5.64plusmn;3.72）ng/ml］ were slightly lower than the control group ［（10.14plusmn;4.48） ng/ml］, the difference was not statistical significance (t=0.780, P=0.437).Conclusion People with lower serum vitamin B12have higher risk of exudative AMD. Low levels of serum vitamin B12 may relate with the occurrence of exudative AMD.
Objective To determine the genotype distribution of methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C and methionine synthase reductase (MTRR) A66G involved in the folic acid biosynthetic pathway among Chinese Han women in Sichuan, so as to provide pregnant women with guidance of supplementing folic acid. Methods By means of Taqman-MGB, 2382 samples from Deyang region in Sichuan province were tested for detecting the genotype distributions and allele frequencies of MTHFR C677T, MTHFR A1298C and MTRR A66G polymorphisms, and then the results were compared with published data in Shandong, Henan and Hainan provinces. Results The allele frequencies of MTHFR C677T were 63.45 and 36.55, those of MTHFR A1298C were 78.20 and 21.80, and those of MTRR A66G were 72.81 and 27.19. There were significant differences in allele distribution of MTHFR C677T and A1298C between Sichuan Han women and other region population. Conclusion This study suggests that the polymorphism of MTHFR C677T and A1298C exhibits region heterogeneity. The polymorphisms of MTHFR may play a role in neural tube defects (NTDs) risk, so periconceptional folic acid supplementation and healthcare following gene polymorphism testing may be a powerful measure to decrease congenital malformations of the central nervous system.
ObjectiveTo observe serum homocysteine (Hcy) levels in retinal vein occlusion (RVO) patients with different ages and types. MethodsA total of 79 patients (79 eyes) diagnosed with RVO were enrolled. There were 33 females and 46 males, the mean age was (57.00±9.29) years. Eighty-two age-and sex-matched patients (82 eyes) without retinal vascular disease were included as controls. There were 32 females and 50 males, the mean age was (60.00±10.15) years. Among RVO patients, there were 24 patients younger than 50 years old (young patients) and 55 patients older than 50 years old (elderly patients); 35 patients with central RVO (CRVO) and 44 patients with branch RVO (BRVO). Fasting plasma Hcy, serum vitamin (Vit) B6, B12 and folate levels were measured in all patients. The relationship of high Hcy, low VitB6, low folate and RVO with different age were analyzed. ResultsHcy level was significantly higher in RVO patients than control subjects (t=2.946, P<0.01). Blood concentration of folate and VitB6 were significantly lower in RVO patients than control subjects (t=2.641, 2.889; P<0.01). Blood level of VitB12 was significantly different in RVO patients from control subjects (t=1.665, P>0.05). Concentrations of Hcy, folate, VitB12 and VitB6 were not different between patients with CRVO and BRVO (t=0.756,1.306,0.682,1.306;P>0.05). Hcy level was significantly higher in the young RVO patients than in the elderly RVO patients (t=2.394, P<0.05). Blood concentration of folate and VitB6 were lower in the young RVO patients than in the elderly RVO patients, but the difference were not significant(t=1.318, 1.694; P>0.05). The number of patients with high Hcy [χ2=13.67,odds ratio (OR)=3.327,95% confidence interval (CI)=1.742-6.354], low VitB6 (χ2=5.28,OR=2.068,95%CI=1.103-3.878) and low folate status (χ2=8.642,OR=2.546,95%CI=1.349-4.806) in RVO patients were more than control subjects (P=0.0001, 0.023, 0.004). ConclusionsHigh Hcy, low folate and low VitB6 were risk factors for the onset of RVO. Hcy may play more important role in young patients with RVO. Hcy, folate and VitB6 levels were similar in CRVO and BRVO patients.
ObjectivesTo systematically review the efficacy of folic acid supplementation in the primary prevention of stroke among patients with H-Type hypertension.MethodsPubMed, EMbase, The Cochrane Library, WanFang Data, CNKI, VIP and Sinomed databases were electronically searched to collect randomized controlled trials (RCTs) of folic acid supplementation in the primary prevention of stroke among patients with H-Type hypertension from inception to April, 2020. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software and Stata 12.0 software.ResultsA total of 12 RCTs involving 18 170 participants were included. The results of meta-analysis showed that H-Type hypertensive patients who received folic acid and antihypertensive had a significant low risk of stroke (RR=0.34, 95%CI 0.21 to 0.55, P<0.000 1) compared with patients who received antihypertensive alone. In the stratified analyses, folic acid >2 mg/d (RR=0.27, 95%CI 0.14 to 0.51, P<0.000 1) and ≤2 mg/d (RR=0.36, 95%CI 0.20 to 0.65, P=0.000 8) both could reduce the risk of stroke. Enalapril folic acid tablets (RR=0.35, 95%CI 0.16 to 0.77, P=0.009) and free combinations of folic acid and antihypertensive drugs (RR=0.29, 95%CI 0.18 to 0.47, P<0.000 01) could lower the incidence of stroke.ConclusionsCurrent evidence shows that the folic acid supplementation significantly reduce the risk of stroke among patients with H-Type hypertension. Enalapril folic acid tablets and free combinations of folic acid with antihypertensive drugs both play an important role in stroke prevention. There is no significant dose-response relationship between dosage of folic acid and prevention of stroke. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify above conclusions.
ObjectiveTo systematically review the association between folic acid supplementation before and/or during pregnancy and the risk for gestational diabetes mellitus (GDM). MethodsThe PubMed, EMbase, The Cochrane Library, SinoMed and CNKI databases were searched to collect studies on folic acid supplementation and GDM from inception to November 2021. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies. Meta-analysis was then performed using RevMan 5.4 software. ResultsA total of 19 studies involving 53 128 cases were included. The results of meta-analysis showed that there was no significant association between folic acid supplementation and the risk for GDM (RR=0.98, 95%CI 0.85 to 1.13, P=0.74). Subgroup analysis revealed that folic acid supplementation was associated with a decreased risk for GDM in Europe and the United States (RR=0.81, 95%CI 0.71 to 0.92, P<0.001), in areas that fortified grain cereal products with folic acid (RR=0.81, 95%CI 0.69 to 0.94, P=0.005). ConclusionThere is no significant association between folic acid supplementation and the risk for GDM. However, supplementation may decrease the risk for GDM among women in Europe and the United States. Due to the limited quantity and quality of the included studies, more high-quality studies are needed to verify the above conclusion.
ObjectiveTo investigate the effect of folic acid coated-crosslinked urethane-doped polyester elastomer (fCUPE) nerve conduit in repairing long distance peripheral nerve injury. MethodsThirty-six 3-month-old male Sprague Dawley rats weighing 180-220 g were randomly assigned to 3 groups, each consisting of 12 rats: CUPE nerve conduit transplantation group (group A), fCUPE nerve conduit transplantation group (group B), and autologous nerve transplantation group (group C), the contralateral healthy limb of group C served as the control group (group D). A 20-mm-long sciatic nerve defect model was established in rats, and corresponding materials were used to repair the nerve defect according to the group. The sciatic function index (SFI) of groups A-C was calculated using the Bain formula at 1, 2, and 3 months after operation. The nerve conduction velocity (NCV) of the affected side in groups A-D was assessed using neuroelectrophysiological techniques. At 3 months after operation, the regenerated nerve tissue was collected from groups A-C for S-100 immunohistochemical staining and Schwann cell count in groups A and B to compare the level of nerve repair and regeneration in each group. ResultsAt 3 months after operation, the nerve conduits in all groups partially degraded. There was no significant adhesion between the nerve and the conduit and the surrounding tissues, the conduit was well connected with the distal and proximal nerves, and the nerve-like tissues in the conduit could be observed when the nerve conduit stents were cut off. SFI in group A was significantly higher than that in group C at each time point after operation and was significantly higher than that in group B at 2 and 3 months after operation (P<0.05). There was no significant difference in SFI between groups B and C at each time point after operation (P>0.05). NCV in group A was significantly slower than that in the other 3 groups at each time point after operation (P<0.05). The NCV of groups B and C were slower than that of group D, but the difference was significant only at 1 month after operation (P<0.05). There was no significant difference between groups B and C at each time point after operation (P>0.05). Immunohistochemical staining showed that the nerve tissue of group A had an abnormal cavo-like structure, light tissue staining, and many non-Schwann cells. In group B, a large quantity of normal neural structures was observed, the staining was deeper than that in group A, and the distribution of dedifferentiated Schwann cells was obvious. In group C, the nerve bundles were arranged neatly, and the tissue staining was the deepest. The number of Schwann cells in group B was (727.50±57.60) cells/mm2, which was significantly more than that in group A [(298.33±153.12) cells/mm2] (t=6.139, P<0.001). ConclusionThe fCUPE nerve conduit is effective in repairing long-distance sciatic nerve defects and is comparable to autologous nerve grafts. It has the potential to be used as a substitute material for peripheral nerve defect transplantation.