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BACKGROUND: Despite the fact that thyroid surgery has evolved towards minimal incisions and endoscopic approaches, the role of total endoscopic thyroidectomy (TET) in thyroid cancer has been highly disputed. We performed a systematic review and meta-analyses of peer reviewed studies in order to evaluate the safety and effectiveness of TET compared with conventional open thyroidectomy (COT) in papillary thyroid cancer (PTC). METHOD: Medical literature databases such as PubMed, Embase, the Cochrane Library, and Web of science were systematically searched for articles that compared TET and COT in PTC treatment from database inception until March 2019. The quality of the studies included in the review was evaluated using the Downs and Black scale using Review Manager software Stata V.13.0 for the meta-analysis. RESULTS: The systematic review and meta-analysis were based on 5664 cases selected from twenty publications. Criteria used to determine surgical completeness included postoperative thyroglobulin (TG) levels, recurrence of the tumor after long-term follow-up. Adverse event and complication rate scores included transient recurrent laryngeal nerve (RLN) palsy, permanent RLN palsy, transient hypocalcaemia, permanent hypocalcaemia, operative time, number of removed lymph nodes, length of hospital stay and patient cosmetic satisfaction. TET was found to be generally equivalent to COT in terms of surgical completeness and adverse event rate, although TET resulted in lower levels of transient hypocalcemia (OR 1.66; p < 0.05), a smaller number of the retrieved lymph nodes (WMD 0.46; p < 0.05), and better cosmetic satisfaction (WMD 1.73; p < 0.05). COT was associated with a shorter operation time (WMD - 50.28; p < 0.05) and lower rates of transient RLN palsy (OR 0.41; p < 0.05). CONCLUSIONS: The results show that in terms of safety and efficacy, TET was similar to COT for the treatment of thyroid cancer. Indeed, the tumor recurrence rates and the level of surgical completeness in TET are similar to those obtained for COT. TET was associated with significantly lower levels of transient hypocalcemia and better cosmetic satisfaction, and thus is the better option for patients with cosmetic concerns. Overall, randomized clinical trials and studies with larger patient cohorts and long-term follow-up data are required to further demonstrate the value of the TET.
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Endoscopia/métodos , Câncer Papilífero da Tireoide/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Currently, many surgeons place a prophylactic drain in the abdominal or pelvic cavity after colorectal anastomosis as a conventional treatment. However, some trials have demonstrated that this procedure may not be beneficial to the patients. OBJECTIVE: To determine whether prophylactic placement of a drain in colorectal anastomosis can reduce postoperative complications. METHODS: We systematically searched all the electronic databases for randomized controlled trials (RCTs) that compared routine use of drainage to non-drainage regimes after colorectal anastomosis, using the terms "colorectal" or "colon/colonic" or "rectum/rectal" and "anastomo*" and "drain or drainage." Reference lists of relevant articles, conference proceedings, and ongoing trial databases were also screened. Primary outcome measures were clinical and radiological anastomotic leakage. Secondary outcome measures included mortality, wound infection, re-operation, and respiratory complications. We assessed the eligible studies for risk of bias using the Cochrane Risk of Bias Tool. Two authors independently extracted data. RESULTS: Eleven RCTs were included (1803 patients in total, 939 patients in the drain group and 864 patients in the no drain group). Meta-analysis showed that there was no statistically significant differences between the drain group and the no drain group in (1) overall anastomotic leakage (relative risk (RR) = 1.14, 95 % confidence interval (CI) 0.80-1.62, P = 0.47), (2) clinical anastomotic leakage (RR = 1.39, 95 % CI 0.80-2.39, P = 0.24), (3) radiologic anastomotic leakage (RR = 0.92, 95 % CI 0.56-1.51, P = 0.74), (4) mortality (RR = 0.94, 95 % CI 0.57-1.55, P = 0.81), (5) wound infection (RR = 1.19, 95 % CI 0.84-1.69, P = 0.34), (6) re-operation (RR = 1.18, 95 % CI 0.75-1.85, P = 0.47), and (7) respiratory complications (RR = 0.82, 95 % CI 0.55-1.23, P = 0.34). CONCLUSIONS: Routine use of prophylactic drainage in colorectal anastomosis does not benefit in decreasing postoperative complications.
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Anastomose Cirúrgica/métodos , Colo/cirurgia , Drenagem , Reto/cirurgia , Adulto , Idoso , Anastomose Cirúrgica/efeitos adversos , Anastomose Cirúrgica/mortalidade , Fístula Anastomótica/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Reoperação , Risco , Infecção da Ferida Cirúrgica/etiologia , Resultado do TratamentoRESUMO
Ten lignans, including six previously undescribed phenolic ester glycosyl lignans (1-6), were isolated from a well-known traditional Chinese medicine, Qin-Jiao, which is the dry root of Gentiana macrophylla Pall. (Gentianaceae). Their structures were determined by spectroscopic and chemical methods, especially 2D NMR techniques. Quantum chemical calculations of theoretical ECD spectra allowed the determination of their absolute configurations. Refer to its traditional applications for the treatment of rheumatic arthralgia and hepatopathy, these compounds were evaluated on a TNF-α induced MH7A human synoviocyte inflammation model and a D-GalN induced AML12 hepatocyte injury model. Compounds 1, 2, 5, and 6 significantly reduced the release of proinflammatory cytokine IL-1ß in MH7A cells at 15 µM and they also could strongly protect AML12 cells against D-GalN injury at 30 µM. Flow cytometry and Western blot analysis showed that compound 5 ameliorated D-GalN induced AML12 cell apoptosis by upregulating the expression of anti-apoptotic Bcl-2 protein and down-regulating the expression of pro-apoptotic Bax protein.
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Medicamentos de Ervas Chinesas , Gentiana , Lignanas , Humanos , Gentiana/química , Lignanas/farmacologia , Glucosídeos/farmacologia , Glucosídeos/química , Medicamentos de Ervas Chinesas/farmacologia , InflamaçãoRESUMO
The Chinese giant salamander (Andrias davidianus), one of the largest extant amphibian species, has dramatically declined in the wild. As an ectotherm, it may be further threatened by climate change. Therefore, understanding the thermal physiology of this species should be the priority to formulate related conservation strategies. In this study, the plasticity in metabolic rate and thermal tolerance limits of A. davidianus larvae were studied. Specifically, the larvae were acclimated to three temperature levels (7 °C, cold stress; 15 °C, optimum; and 25 °C, heat stress) and two diet items (red worm or fish fray) for 20 days. Our results indicated that cold-acclimated larvae showed increased metabolic capacity, while warm-acclimated larvae showed a decrease in metabolic capacity. These results suggested the existence of thermal compensation. Moreover, the thermal tolerance windows of cold-acclimated and warm-acclimated larvae shifted to cooler and hotter ranges, respectively. Metabolic capacity is not affected by diet but fish-fed larvae showed superiority in both cold and heat tolerance, potentially due to the input of greater nutrient loads. Overall, our results suggested a plastic thermal tolerance of A. davidianus in response to temperature and diet variations. These results are meaningful in guiding the conservation of this species.
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Determination of the transcription level of cellular prion protein (PrP(C)) is essential for understanding its role in organisms and revealing mechanism of susceptibility and resistance to scrapie. However, the expression of prion protein (PrP) mRNA in sheep has not been quantified in great detail in digestive tract which is important during scrapie spread through oral route. Herein, we report on measurement of sheep PrP mRNA using absolute quantitative real-time RT-PCR. Total RNA was isolated from five different regions of the central nervous system (CNS), four regions of lymphoid system, eleven regions of digestive tract, and two reproductive organ tissues of eight sheep of two different genotypes (ARR/ARQ and ARH/ARQ) and PrP mRNA was quantified by real-time RT-PCR using molecular beacon. The results showed that highest levels of PrP mRNA were expressed in thalamus and cerebrum (P < 0.01) of CNS examined, followed by cerebellum, spinal cord, and brain stem. In peripheral organs examined, lymph tissue showed moderate level of PrP expression similar to that in digestive tract and reproduction organs. PrP expression levels in the same tissue of different genotype sheep had significant variation. Our study provided the first detail, tissue-specific and genotype-specific data of PrP mRNA expression in sheep for further studies of pathogenesis of prion diseases.
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Expressão Gênica , Proteínas PrPC/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Ovinos/genética , Animais , Cérebro/metabolismo , Genótipo , Proteínas PrPC/metabolismo , Ovinos/metabolismo , Tálamo/metabolismoRESUMO
Functional diversity is an integrative approach to better understand biodiversity across space and time. In the present study, we investigated the spatiotemporal patterns (i.e., elevation and season) and environmental determinants of anuran functional diversity on Tianping Mountain, northwest Hunan, China. Specifically, 10 transects were established from low (300 m a.s.l.) to high (1 492 m a.s.l.) elevations, and anuran communities were sampled in spring, early summer, midsummer, and autumn in 2017. Four functional diversity indices were computed for each transect in each season using ecomorphological functional traits. Our results demonstrated that these indices had contrasting responses to increasing elevations. However, they did not differ significantly among seasons in terms of temporal patterns. Interestingly, the unique spatiotemporal functional diversity patterns were impacted by distinct environmental variables, such as leaf litter cover, water temperature, number of trees, and water conductivity.
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Distribuição Animal , Anuros/classificação , Biodiversidade , Clima , Florestas , Altitude , Animais , Anuros/fisiologiaRESUMO
OBJECTIVE: To study the effect of simultaneously increasing PTEN gene expression and inhibiting Livin gene expression on the gastric carcinoma cell line (BGC823) and construct a recombinant vector expressing PTEN while simultaneously silencing Livin. METHODS: The siRNA expression unit against Livin gene (siLivin) was cleaved from pRNAT-U6.1-Livin vector and then inserted into pCL-neo-PTE to construct the recombinant vector pCL-neo-PTEN-siLivin. Then pCL-neo-PTEN-siLivinp, pCL-neo-PTEN, pRNAT-U6.1-Livin, pCL-neo and pRNAT-U6.1 were respectively transfected into the gastric carcinoma cell line (BGC823) with LipofectAMINE(TM) 2000. The mRNA and protein expression level of PTEN and Livin genes in each cell group was detected by fluorescent quantitative RT-PCR and Western blot. RESULTS: Recombinant vectors of pCL-neo-PTEN, pRNAT-U6.1-Livin and pCL-neo-PTEN-siLivin were constructed successfully. After transfection with pCL-neo-PTEN-siLivin, the mRNA and protein expression level of PTEN (0.897±0.112) rose in BGC823 cells while Livin gene became silenced. And the characterization of regulated cell bioactivity improved. There were significant differences between transfected and control groups (P<0.05). And the inhibiting effect on the proliferation and metastasis of BGC823 cell by increasing PTEN expression and silencing Livin simultaneously was better than that only by regulating PTEN genes or Livin genes alternatively. CONCLUSION: The recombinant vector of expressing PTEN and silencing Livin gene simultaneously is successfully constructed.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Inativação Gênica , Vetores Genéticos , Proteínas Inibidoras de Apoptose/genética , Proteínas de Neoplasias/genética , PTEN Fosfo-Hidrolase/genética , Linhagem Celular Tumoral , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , RNA Interferente Pequeno/genética , TransfecçãoRESUMO
The research developed a diazo-coupling carbon-dots (CDs) method for determining nitrite and optimized variables of sodium sulfanilate, CDs synthesis, characteristic wavelength, reaction time and temperature. The method can assay 0.025-2.0 mg/L NO2- and has a detection limit of 9.6 µg/L and 95-105% recovery. Subsequently, it was applied in detecting NO2- changes in some Chinese home cooking, the gotten results indicated that if the sautéed vegetables (cabbage, Chinese cabbage, spinach and lettuce) and stir-fry pork, fried peas and pickled vegetable are stored at 4 °C for 72 h, nitrite contents are far lower than the recommended value, but if stored at room temperature for 24 h, the content in pure vegetables and shredded pork with green pepper will exceed the recommended value. Therefore, the staying fresher for the sautéed vegetables at room temperature is 24 h, if stored in a refrigerator at 4 °C, their staying fresher can be extended to 72 h.
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Culinária , Nitritos/análise , Verduras/química , Carbono/análise , Dicroísmo Circular , Temperatura AltaRESUMO
Exploring species richness patterns across space and time can help in understanding species distribution and in formulating conservation strategies. Among taxa, amphibians are of utmost importance as they are highly sensitive to environmental changes due to their unique life histories (Zhong et al., 2018). Here, we investigated the spatial and temporal patterns of amphibian species richness on Tianping Mountain in China. Specifically, we established 10 transects at low to high elevations, and sampled amphibians in April, June, August, and October 2017. Our results demonstrated that amphibian species composition and richness varied significantly at both spatial and temporal scales and were associated with gradients of environmental change in microhabitats on Tianping Mountain.
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Anfíbios , Biodiversidade , Animais , China , Meio Ambiente , Análise Espaço-TemporalRESUMO
The increased expression of cluster of differentiation (CD)47 has been identified in a number of different tumor types and is recognized as an adverse prognostic factor that indicates an increased risk of mortality in patients. The binding of CD47 to signal regulatory protein α (SIRPα) inhibits the macrophage phagocytosis of tumor cells by triggering an inhibitory 'do not eat me' signal. This is one of the mechanisms used by tumor cells to evade immune surveillance. In the present study, CD47 levels and macrophage infiltration were assessed in patients with esophageal squamous cell cancer (ESCC). CD47-overexpressing ESCC cell lines were selected and human M2 macrophage phagocytic activity was measured. The results revealed that CD47 is highly expressed and macrophages are markedly infiltrated in cancerous tissue compared with non-cancerous tissue. High CD47 expression was detected in ESCC cell lines and the results of a phagocytosis assay indicated that human M2 macrophages phagocytized tumor cells in a dose-dependent manner following the blocking of CD47-SIRPα signaling by anti-CD47 antibodies. The results of the present study therefore support the use of anti-CD47 immunotherapy to treat patients with ESCC.
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Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and Livin are important in the development of gastric cancer (GC). PTEN and Livin are involved in the regulation of tumor cell proliferation, migration and apoptosis. The modulation of PTEN or Livin has been investigated extensively in various cancer models. However, no studies have been performed to evaluate the combined effect of concurrently modulating these two genes on the development of GC. In the present study, the BGC823 human gastric carcinoma cell line was transfected with a dual gene modified vector (pCL-neo-PTEN-siLivin) in parallel with single gene modified vectors (pCLneoPTEN or pRNATU6.1siLivin), and an empty control vector. Dual gene modulation (pCLneoPTENsiLivin) had a more marked effect on the inhibition of cell proliferation, induction of apoptosis, and reduction of cell penetration in Matrigel, compared with either single gene alone or empty vector transfection. In a xenograft nude mouse model, the inoculation of pCLneoPTENsiLivintransfected BGC823 cells led to a markedly reduced tumor burden, compared with that in all other inoculation groups. In conclusion, the overexpression of PTEN concomitant with Livin gene silencing was confirmed as a feasible and effective in vitro and in vivo gene modulation method, which may represent a potential therapeutic strategy for the treatment of GC.
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Proteínas Adaptadoras de Transdução de Sinal/genética , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos/uso terapêutico , Proteínas Inibidoras de Apoptose/genética , Proteínas de Neoplasias/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Animais , Apoptose , Linhagem Celular Tumoral , Inativação Gênica , Terapia Genética/métodos , Vetores Genéticos/genética , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Regulação para CimaRESUMO
Previous studies have demonstrated that microRNAs (miRNAs) are associated with tumor development and progression. miRNA-524-5p (miR-524-5p) has been reported to be involved in the development and progression of several types of cancer, but its role in gastric cancer has not been fully elucidated to date. Therefore, the aim of the present study was to investigate the expression levels and function of miR-524-5p in human gastric cancer. The expression levels of miR-524-5p were assessed in gastric cancer specimens and cell lines, including MKN-45, SGC-7901 and MGC-803 cell lines and gastric epithelial mucosa GES-1 cells, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Cell proliferation and cell apoptosis assays and invasion analysis in gastric cancer cell lines were performed to evaluate the effects of miR-524-5p on gastric cancer cells in vitro. The expression levels of matrix metallopeptidase (MMP)-2 and MMP-9 were determined by RT-qPCR and western blot analysis. The expression of miR-524-5p was significantly decreased in gastric cancer tissues and cell lines. Additionally, the results of the in vitro experiments demonstrated that overexpression of miR-524-5p inhibited cell proliferation and invasion, and promoted cell apoptosis in gastric cancer cells. Human gastric cancer SGC-7901 and MGC-803 cell lines transfected with miR-524-5p exhibited reduced expression levels of MMP-2 and MMP-9. Taken together, the results of the present study indicated that miR-524-5p may function as a novel tumor suppressor gene in gastric cancer, and may serve as a biomarker and therapeutic target for the treatment of gastric cancer.
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Increasing study reports that Wnt/ß-catenin signaling pathway plays an essential role in numerous cancers growth, progression and metastasis. Aberrant miR-940 expression has been studied in gastric and breast cancer. However, the molecular mechanism of miR-940 enhancing proliferation and metastatic ability in human pancreatic carcinoma is far from to know. Real-time PCR was used to quantify miR-940 expression. Luciferase reporter assays here were performed to verify the activity of Wnt/ß-catenin signaling pathway and targeting gene relationships, and immunofluorescence assay was applied to observe ß-catenin expressed intensity. Bioinformatics analysis together with in vivo and vitro functional analysis indicated the potential targeting genes of miR-940. Specimens from 15 pairs of patients with human pancreatic carcinoma were involoved to confirm the relationship between miR-940 expression and the GSK3ß/sFRP1 through real-time PCR and western blot assays. Bioinformatics combined with cell luciferase function researches determined the possible regulation of miR-940 on the 3'-UTR of the GSK3ß and sFRP1 genes, resulting in the Wnt/ß-catenin signaling activation. Further, miR-940 knockdown significantly recovered GSK3ß and sFRP1 expression and relieved Wnt/ß-catenin-mediated cell invasion, migration, metastasis and proliferation. The ectopic up-regulation of miR-940 significantly suppressed GSK3ß/sFRP1 expression and promoted pancreatic carcinoma proliferation and invasion. Our study suggested mechanistic relationship between miR-940 and Wnt/ß-catenin in the development and progression of pancreatic carcinoma through regulation of GSK3ß and sFRP1.
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Glicogênio Sintase Quinase 3 beta/metabolismo , MicroRNAs/metabolismo , Neoplasias Pancreáticas/enzimologia , Neoplasias Pancreáticas/genética , Proteínas/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Neoplasias Pancreáticas/patologia , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Neoplasias PancreáticasRESUMO
This study was designed to investigate the proliferation inhibition and apoptosis-promoting effect under hyperthermia and chemotherapy treatment, at cellular level. Human gastric cancer cell line SGC-7901 was cultivated with 5-fluorouracil at different temperatures. Cell proliferation and apoptosis were determined, and expression of Bcl-2 and HSP70 was measured at different treatments. Cell survival rates and inhibition rates in chemotherapy group, thermotherapy group, and thermo-chemotherapy group were drastically lower than the control group (P<0.05). For tumor cells in the thermo-chemotherapy group, survival rates and inhibition rates at three different temperatures were all significantly lower than those in chemotherapy group and thermotherapy group (P<0.05). 5-Fluorouracil induced apoptosis of SGC-7901 cells with a strong temperature dependence, which increased gradually with increase in temperature. At 37°C and 43°C there were significant differences between the thermotherapy group and chemotherapy group and between the thermo-chemotherapy group and thermotherapy group (P<0.01). The expression of Bcl-2 was downregulated and HSP70 was upregulated, with increase in temperature in all groups. Cell apoptosis was not significant at 46°C (P>0.05), which was probably due to thermotolerance caused by HSP70 accumulation. These results suggested that hyperthermia combined with 5-fluorouracil had a synergistic effect in promoting apoptosis and enhancing thermotolerance in gastric cancer cell line SGC-7901.
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Our previous findings revealed that FGFR4 may be a novel therapeutic target for gastric cancer. The aim of the present study was to explore the effects of a combination of PD173074 (PD) and 5-fluorouracil (5-Fu) on the biological behavior of gastric cancer cell lines and the relevant mechanisms involved. MKN45, a gastric cancer cell line, was treated with each single agent alone or a combination of FGF19, PD and 5-Fu. Then, a series of functional assays were performed using CCK-8 assay and flow cytometry. Western blot analysis was used to determine the expression of signaling pathway and downstream-related molecules in the MKN45 cells following the different treatments. As the concentration of PD and 5-Fu increased, the cell viability gradually decreased; the viability of the combination group was less than the viability following single administration. Western blot analysis showed that FGFR4 expression was weak in the 5-Fu-treated groups when compared with the control. PD markedly increased the apoptosis rate of MKN45 cells when compared to the control; the apoptosis rate in the cells treated with the combination of PD and 5-Fu was higher than that in the cells following single treatment. Furthermore, PD reduced the expression of p-ERK and Bcl-xl and increased caspase-3 expression. Inhibition of the activity of FGFR4 may be the main mechanisms of PD effect while 5-Fu reduced FGFR4 expression. Furthermore, the effects of the combination of 5-Fu and PD in inhibiting proliferation, increasing apoptosis and arresting cell cycle were superior to these effects following the single agent treatments, suggesting that the two drugs applied in combination may contribute to the effective treatment of gastric cancer.
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Proliferação de Células/efeitos dos fármacos , Fluoruracila/farmacologia , Pirimidinas/farmacologia , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética , Neoplasias Gástricas/tratamento farmacológico , Apoptose/efeitos dos fármacos , Caspase 3/biossíntese , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/biossíntese , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Proteína bcl-X/biossínteseRESUMO
BACKGROUND: Previous studies concerning the association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and colorectal cancer risk in Asian populations generated conflicting results. A meta-analysis was therefore performed to allow a more reliable estimate of any link. METHODS: Relevant studies concerning the association between the MTHFR C677T polymorphism and risk of colorectal cancer were included into this meta-analysis. The quality of the studies was assessed according to a predefined scale. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined for this gene-disease association using fixed or random effect models according to the heterogeneity between included studies. RESULTS: Finally, 21 studies with a total of 6692 cases and 8266 controls were included. Meta-analyses showed that there was an obvious association of the MTHFR 677T allele with decreased risk of colorectal cancer (OR = 0.91, 95%CI=0.85-0.98, P=0.011). Subgroup analyses by country further identified this association, with dietary folate as the main source of heterogeneity. CONCLUSION: The MTHFR 677T allele is associated with a lower risk of colorectal cancer in Asian populations, and there is effect modification by population plasma folate.