A review of salivary composition changes induced by fasting and its impact on health

Human saliva is an indispensable fluid that maintains a healthy oral cavity which otherwise can lead to oral diseases(dental caries and periodontitis).In addition,salivary metabolites and microbiome profile provide early detection of systemic diseases such as cancer and obesity.Salivary diagnostic has gained popularity due to its non-invasive sampling technique.Fasting(abstinence from food or drink or both)research for weight loss and improve health is common,but studies using fasting saliva are scarce.Some metabolites in fasting saliva have been reported with interesting results,which can be enhanced by considering different confounding factors.For example,fasting saliva contains higher salivary nitrite,which is related to nitric oxide(NO).NO is a vasodilator supporting the healthy function of endothelial cells and its deficiency is connected to many diseases.The timely supply of NO through exogenous and endogenous means is highlighted and the potential advantage of fasting salivary composition changes in relation to COVID-19 infection is speculated.This review aims to provide a general discussion on the salivary composition,properties,and functions of the whole saliva,including the health benefits of fasting.

Potential use of a dried saliva spot(DSS)in therapeutic drug monitoring and disease diagnosis

In recent years,scientific researchers have increasingly become interested in noninvasive sampling methods for therapeutic drug monitoring and disease diagnosis.As a result,dried saliva spot(DSS),which is a sampling technique for collecting dried saliva samples,has been widely used as an alternative matrix to serum for the detection of target molecules.Coupling the DSS method with a highly sensitive detection instrument improves the efficiency of the preparation and analysis of biological samples.Furthermore,dried blood spots,dried plasma spots,and dried matrix spots,which are similar to those of the DSS method,are discussed.Compared with alternative biological fluids used in dried spot methods,including serum,tears,urine,and plasma,saliva has the advantage of convenience in terms of sample collection from children or persons with disabilities.This review aims to provide integral strategies and guidelines for dried spot methods to analyze biological samples by illustrating several dried spot methods.Herein,we summarize recent advancements in DSS methods from June 2014 to March 2021 and discuss the advantages and disadvantages of the key aspects of this method,including sample preparation and method validation.Finally,we outline the challenges and prospects of such methods in practical applications.

Multispecies communities:interspecies interactions influence growth on saliva as sole nutritional source

Human oral bacteria live in multispecies communities in the biofilm called dental plaque. This review focuses on the interactions of seven species and the ability of each species individually and together with other species to grow on saliva as the sole source of nutrient. Community formation in biofihns in flow cells is monitored using species-specific fluorophore-conjugated immunoglobulin Gy and images are captured by confocal microscopy. Early colonizing veillonellae emerge from this review of interspecies interactions in saliva as a critical genus that guides the development of multispecies communities. Highly selective interspecies recognition is evident as initial colonizers pair with early and middle colonizers to form multispecies communities that grow on saliva.

Changes of free radicals and digestive enzymes in saliva in cases with deficiency inspleen-yin syndrome

Objective：To explore the nature of deficiency in spleen-yin syndrome,which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine（TCM）syndrome differentiation based on biology,and had a strong clinical significance.Methods：Serum Cu and Zn were detected by atomic absorption spectrophotometer,serum vitamin E by high performance liquid chromatography,serum vitamin C by 2,4-Dinitrophenylhydrazine Colorimetry,total superoxide dismutase（SOD）and Cu and Zn- SOD by the xanthine oxidase method,and malondialdehyde（MDA）by the 2-thiobarbituric acid method（TBA）.Total antioxidant capacity was detected by a colorimetry kit.Amylase Activity was detected by an automatic biochemical analyzer.Lysozyme was detected by lysozyme detection plate,the diameter of bacteriolysis circle was measured and the corresponding content of lysozyme was obtained from a table of standard curve values.Results： No significant difference in total SOD and Cu,Zn-SOD was found between deficiency in spleen-yin group and normal group.However,such factors in deficiency in kidney-yin group were significantly lower than the other groups（P〈0.05）.The MDA content in both deficiency in spleen-yin group and deficiency in kidney-yin group were significantly higher than that of normal group（P〈0.05）,while the total antioxidant capacity was significantly lower than normal group（P〈0.05）.The vitamin E content in deficiency in kidney-yin group was significantly lower than that in the other two groups（P〈0.05）.No significant difference in the contents of vitamin C,Cu and Zn were observed in these groups.The Zn/Cu level in deficiency in kidney-yin group and the vitamin E level in deficiency in spleen-yin group decreased,but with no significant difference.Amylase activity in unit time in cases with deficiency in spleen-yin was lower than and had significant differences with that in normal cases,and higher than that in cases with deficiency in kidney-yin.The sectional velocity of saliva and the ratio of lysozyme in normal case group were significantly higher than other two groups,while deficiency in the spleen-yin group was significantly higher than the deficiency in kidney-yin group.Conclusion：All the results indicated that the objective pathological mechanism between the deficiency in spleen-yin and deficiency in kidney-yin was different.

Prevalence of Enterococcus faecalis in saliva and filled root canals of teeth associated with apical periodontitis

To investigate the prevalence of Enterococcus faecalis in saliva and filled root canals of patients requiring endodontic retreatment for apical periodontitis.Patients with apical periodontitis who were referred for endodontic retreatment were examined.The type and quality of the restoration,symptoms,quality of obturation were recorded.During retreatment,an oral rinse sample and root canal sample were cultured using brain-heart infusion agar and bile esculinazide agar to select for E.faecalis.The 16S rRNA technique was used to identify E.faecalis.A total of 32 women and 22 men（mean age：38 years;s.d.：11 years） and 58 teeth were studied.The prevalence of E.faecalis was 19% in the saliva and 38% in the root canals.The odds that root canals harbored E.faecalis were increased if the saliva habored this bacterium（odds ratio59.7;95% confidence interval51.8-51.6;P,0.05）.Teeth with unsatisfactory root obturation had more cultivable bacterial species in root canals than teeth with satisfactory root obturation（P,0.05）.E.faecalis is more common in root canals of teeth with apical periodontitis than in saliva.The prevalence of E.faecalis in root canals is associated with the presence of E.faecalis in saliva.

Study of Helicobacter pylori genotype status in saliva,dental plaques,stool and gastric biopsy samples

AIM:To compare genotype of Helicobacter pylori(H.pylori) isolated from saliva,dental plaques,gastric biopsy,and stool of each patient in order to evaluate the mode of transmission of H.pylori infection.METHODS:This cross-sectional descriptive study was performed on 300 antral gastric biopsy,saliva,dental plaque and stool samples which were obtained from patients undergoing upper gastrointestinal tract endoscopy referred to endoscopy centre of Hajar hospital of Shahrekord,Iran from March 2010 to February 2011.Initially,H.pylori strains were identified by rapid urease test(RUT) and polymerase chain reaction(PCR) were applied to determine the presence of H.pylori(ureC) and for genotyping of voculating cytotoxin gene A(vacA) and cytotoxin associated gene A(cagA) genesin each specimen.Finally the data were analyzed by using statistical formulas such as Chi-square and Fisher's exact tests to find any significant relationship between these genes and patient's diseases.P < 0.05 was considered statistically significant,RESULTS:Of 300 gastric biopsy samples,77.66% were confirmed to be H.pylori positive by PCR assay while this bacterium were detected in 10.72% of saliva,71.67% of stool samples.We were not able to find it in dental plaque specimens.The prevalence of H.pylori was 90.47% among patients with peptic ulcer disease(PUD),80% among patients with gastric cancer,and 74.13% among patients with none ulcer dyspepsia(NUD) by PCR assay.The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens.94.42% of H.pylori positive specimens were cagA positive and all samples had amplified band both for vacA s and m regions.There was significant relationship between vacA s1a/m1a and PUD diseases(P = 0.04),s2/m2 genotype and NUD diseases(P = 0.05).No statically significant relationship was found between cagA status with clinical outcomes and vacA genotypes(P = 0.65).The evaluation of vacA and cagA genes showed 6 differences between gastric biopsy and saliva specimens and 11 differences between gastric and stool specimens,CONCLUSION:Regard to high similarity in genotype of H.pylori isolates from saliva,stomach and stool,this study support the idea which fecal-oral is the main route of H.pylori transmission and oral cavity may serve as a reservoir for H.pylori,however,remarkable genotype diversity among stomach,saliva and stool samples showed that more than one H.pylori genotype may exist in a same patient.

水杨酸对NaCl胁迫下水稻(Oryza Saliva L.)幼苗生理活性的影响

用0.2%水杨酸处理1.2%NaCl胁迫下的水稻种子,测定其以下几个生理指标:种子的发芽率、发芽势和幼苗中的酯酶、过氧化氢酶以及抗坏血酸的含量.实验结果显示:外源性水杨酸能够相对提高NaCl胁迫下水稻种子萌发后幼苗的过氧化物酶活性和抗坏血酸的含量,同时也能提高水稻种子的发芽率、发芽势,但对酯酶活性影响不大.研究表明水杨酸能提高水稻种子萌发后幼苗的抗盐性,并使水稻种子出苗整齐、一致.

Low Temperature Degradation of Alumina-toughened Zirconia in Artificial Saliva

The long-term aging behavior of an alumina-toughened zirconia （ATZ） ceramic in artificial saliva hydrothermal atmosphere was determined and compared with that of tetragonal zirconia polycrystals doped with 3mo1% Y203 （3Y-TZP）. The specimens of 3Y-TZP and ATZ were aged in distilled water and artificial salivary respectively at 134 ~C. Monoclinic phase content was evaluated by X-ray diffraction （XRD） analysis. Specimen strength was determined by a biaxial bending test. Surface screening was done using an atomic force microscope （AFM）. No statistically significant influence of any treatment on strength was demonstrated for either material. However, XRD measurements revealed ATZ＇s anti-aging properties were much better than TZP after the aging treatment. Therefore, ATZ can be applied to the field of dentistry. Artificial saliva in ceramic surface sediments may be useful for stren^heninl ceramics.

Si,Fe and Mn Distributions in Rice (Oryza saliva L.) Rhizosphere of Red Earths and Paddy Soils

An experiment using rhizobox was conducted to study Si, Fe and Mn distributions in rice rhizosphcre of red earths and paddy soils. It was found that Si, Fe and Mn distributions in rhizosphere of the paddy soils were characterized by a depleted zone around root surface, beyond which the concentrations gradually rose. From lmm layer to 2mm layer the concentrations dropped and then rose again. Whereas Si and Fe in red earths showed no depleted zone but even accumulated zone around root surface. Mn showed an approximately even distribution in each layer and no depletion was found in root surface layers. This indicated that during rice (Oryza sativa L.)plantation, depletion and accumulation of Si, Fe and Mn in rhizosphere were important features of matured red earths by water culture. The distribution changes of Si, Fe and Mn in relation to soil-root interaction are also discussed.

CLINICAL APPLICATION AND EVALUATION OF SALIVA FERNING TEST IN SJGREN' S SYNDROME

Objective To evaluate the saliva ferning test (SFT) as diagnostic test for xerostomia in patients with Sjogren’s Syndrome (SS). Methods In this study, dried samples of freshly produced saliva from 78 patients with established SS according to European Community criteria and 80 healthy controls were examined by light microscopy. The crystallization was classified into 4 types according to the ferning phenomenon: uniformity, branching, spreading and integrity (type I normal and type Ⅱ,Ⅲ,Ⅳ abnormal ). Then, the 78 patients underwent lebial salivary gland biopsy. According to Tarpley’s classifica- tion, minor salivary gland biopsy (≥2 + ) was considered to be positive . Results 1. The sensitivity of SFT was high (70/ 78 = 89. 74% ). And the specificity wes also high (67/80 = 83. 75% ). 2. Abnormal SFT was observed in 70/78 (89. 74% ) samples from patients group and in 13 /80 (16. 25% ) samples from healthy controls. The differences of SFT in patients group versus controls were statistically significant (P< 0. 01 ). 3. The sensitivity of SFT and mini labial gland biopsy had no significant differences (P > 0. 05) as diagnostic tests in SS. Conclusion SFT was simple, sensitive and specific as diagnostic test in SS suspect patients just as mini labial gland biopsy.

Anti-oxidation actions of curcumin in two forms of bed rest:oxidative stress serum and salivary markers

Objective:To determine the preventive effects of curcumin on peroxidative damage under two bed rest conditions.Methods:20 healthy male(10 with curcumin and 10 without curcumin ) volunteers were selected.They were studied before,during,and just on bed rest conditions at -6°head-down-tilt(HDT) bed rest and bed rest position(BD) for 10 days.We measured the salivary and serum oxidative markers such as Malonaldehyde,8-hydroxydeoxyguanosine, vitamin C and E just before HDT & BD.during HDT & BD experiment,and in course time of recovery with curcumin and without curcumin groups.Results:The values of serum and salivary vitamin C & E showed statistically significant decrease in both bed rest conditions as compared to those of the conditions before and during the recovery stage.However,these levels were not significantly lowered in curcumin groups in contrast to the groups without curcumin (P】0.05).MDA and 8-OHdG levels showed significant increase in simulating microgravity and zero gravity conditions as compared to those before and in the recovery stage.However,these levels were lower in curcumin groups in contrast to the groups without curcumin(P【0.05).Serum and salivary correlation analysis revealed a strong and highly significant correlation for MDA. vitamin C & E and 8 dihydro-2 deoxyguanosine(8-OHdG) in the conditions before,during and in the recovery periods in both bed rest conditions.Since saliva collection is easy and noninvasive, measurements of salivary marker levels may prove to be useful in the space research. Conclusions:Curcumin prevents peroxidative damage in both bed rest conditions.Further study is required on antioxidation actions of curcumin in space microgravity conditions.

Interferon-c and interleukin-4 detected in serum and saliva from patients with oral lichen planus

Our previous salivary study had demonstrated an apparent T helper 2 （Th2）-predominance in saliva of oral lichen planus （OLP） patients and suggested a potential of salivary interleukin-4 （IL-4） as a biomarker for monitoring disease severity. To further determine the consistency of Th1/Th2 bias of OLP, this study investigated the expression profile of interferon-γ （IFN-γ） and IL-4 in serum and the relationship of the serum levels of these cytokines with their saliva partners. Sixty ethnic Chinese patients with OLP （40 of the erythematous/ulcerative form and 20 of the reticular form） were recruited for this study, with 40 age-sex-matched healthy volunteers as control group. IFN-γ and IL-4 levels in serum and paired saliva samples were screened by enzyme-linked immunosorbent assay. OLP patient showed a low-level IFN-γ but high-level IL-4 expression profile in both serum and saliva, with a lower IFN-γ/IL-4 ratio. Serum IL-4 level in the erythematous/ulcerative group was significantly higher than that in the reticular group. Serum levels of IFN-γ and IL-4 were significantly and positively correlated with their saliva partners. These results provided more evidence for Th2 cytokine- predominant immune imbalance in OLP, as well as the potential of IL-4 as the biomarker for monitoring severity of OLP.

Bioinformatics advances in saliva diagnostics

There is a need recognized by the National Institute of Dental ＆ Craniofacial Research and the National Cancer Institute to advance basic, translational and clinical saliva research. The goal of the Salivaomics Knowledge Base （SKB） is to create a data management system and web resource constructed to support human salivaomics research. To maximize the utility of the SKB for retrieval, integration and analysis of data, we have developed the Saliva Ontology and SDxMart. This article reviews the informatics advances in saliva diagnostics made possible by the Saliva Ontology and SDxMart.

Effect of Saliva Contamination on Shear Bond Strength of Orthodontic Brackets When Using a Self-Etch Primer

The effect of saliva contamination on the shear bond strength of orthodontic brackets, at various stages of the bonding procedure using a new self-etch primer was studied. The samples were divided into 4 groups according to 4 different enamel surface conditions: Group A: dry; Group B: saliva contamination before priming; Group C: saliva contamination after priming, and Group D: saliva contamination before and after priming. Stainless steel brackets were bonded in each test group with a light-cured composite resin (TransbondXT 3M). The shear bond strength was determined in the first 30 min after bonding. The analysis of variance indicated that the shear bond strengths of the 4 groups were significantly different (F=11.89, P<0.05). Tukey HSD tests indicated that contamination both before and after the application of the acid-etch primer resulted in a significantly lower (=4.6±1.7 MPa) shear bond strength than either the control group (=8.8±1.9 MPa) or the groups where contamination occurred either before (=7.9±2.0 MPa) or after (=6.9±1.5 MPa) the application of the primer. It was concluded that the new acid-etch primer could maintain adequate shear bond strength if contamination occurred either before or after the application of the primer. On the other hand, contamination both before and after the application of the primer could significantly reduce the shear bond strength of orthodontic brackets.

Inflammation-related gene expression profiles of salivary extracellular vesicles in patients with head trauma

At present,there is no reliable biomarker for the diagnosis of traumatic brain injury(TBI).Studies have shown that extracellular vesicles released by damaged cells into biological fluids can be used as potential biomarkers for diagnosis of TBI and evaluation of TBI severity.We hypothesize that the genetic profile of salivary extracellular vesicles in patients with head trauma differs from that in uninjured subjects.Findings from this hypothesis would help investigate the severity of TBI.This study included 19 subjects,consisting of seven healthy controls who denied history of head trauma,six patients diagnosed with concussion injury from an outpatient concussion clinic,and six patients with TBI who received treatment in the emergency department within 24 hours after injury.Real-time PCR analysis of salivary extracellular vesicles in participants was performed using TaqMan Human Inflammation array.Gene expression analysis revealed nine upregulated genes in emergency department patients(LOX5,ANXA3,CASP1,IL2RG,ITGAM,ITGB2,LTA4H,MAPK14,and TNFRSF1A)and 13 upregulated genes in concussion clinic patients compared with healthy participants(ADRB1,ADRB2,BDKRB1,HRH1,HRH2,LTB4R2,LTB4R,PTAFR,CYSLTR1,CES1,KLK1,MC2R,and PTGER3).Each patient group had a unique profile.Comparison between groups showed that 15 inflammation-related genes had significant expression change.Our results indicate that inflammation biomarkers can be used for diagnosis of TBI and evaluation of disease severity.This study was approved by the Institutional Review Board on December 18,2015(approval No.0078-12)and on June 9,2016(approval No.4093-16).

Maternal Blood Milk Saliva Sample Selection and the Transmission of Hepatitis B Virus Infectious Research

Background: Hepatitis B is an infectious disease, which is a main way of vertical transmission of infectious HBV between mother and infant. Hepatitis B virus infection is always a hot topic of social concern, especially in China. The paper studies hepatitis B virus in maternal blood, breast milk, saliva of hepatitis B virus infection model (HBV-M) in Hefei city, Anhui province, PRC. HBV-DNA load and related data in Hefei city are used for risk assessment of the transmission of hepatitis B virus to provide evidence for evidence-based medicine and scientific guidance of infant feeding patterns. Methods: On the principle of informed consent, inpatient hepatitis B maternal blood 695, breast milk, saliva 614,169 copies were used as the object of analysis, using the ELISA method for the detection of HBV-M, using real-time fluorescence quantitative PCR detection of HBV-DNA load. We analyze HBsAg in saliva, milk, the positive rate of HBV-DNA and HBV-M in serum, saliva, milk, and explore the positive rate of HBV-DNA and serum HBV-DNA load correlation. Results: At the age of 18 - 44 years old perinatal women, HBV-DNA positive rates of maternal serum, breast milk, saliva were 157 cases in A group HBsAg, HBeAg positive: 99.36%, 88.06%, 96.77%;in 312 cases in group B, HBeAb HBsAg, HBcAb positive: 17.63%, 2.93%, 54.67%;69 cases in C group HBsAg, HBcAb positive: 63.77%, 27.27%, 28.57%;D group of 71 patients with simple HBcAb positive: 12.68%, 3.13%, 0%;E group and 86 cases in control group HBVM: 1.16%, 0%, 0%. According to the serum and milk testing of Group A and Group B, HBV-DNA chi-square is χ2 = 237.45, P;there is a significant difference in serum and saliva;HBV-DNA chi-square χ2 = 289.49, P < 0.01, the difference has statistical significance. Conclusion: 1) HBV-DNA load high maternal blood, breast milk, saliva are potentially persistent hepatitis B virus infection risk, especially infectious blood. 2) Of maternal milk, saliva and blood HBV-DNA HBV-DNA load were positively correlated (r = 0.96;P ing, breast milk and saliva HBV-DNA positive rates were increased and infectivity enhanced. 3) Maternal blood, breast milk, saliva specimens for any HBV-DNA ≥ 1000 copies/ml are not breastfeeding. 4) The mother who carries the hepatitis B virus cannot do maternal infant feeding, and deep kiss intimate contact, in order to prevent blood, saliva and other ways of infection of hepatitis B virus. 5) Saliva testing is instead of milk inspection, because saliva is easier;

Identification of antigenic proteins from salivary glands of female Anopheles maculatus by proteomic analysis

Objective: To identify antigenic proteins from the salivary glands of female Anopheles maculatus using a proteomic approach to find the biomarker candidate for serological tools.Methods: The identification of antigenic proteins of Anopheles maculatus salivary gland used these techniques: one-dimensional gel electrophoresis(sodium dodecyl sulfate polyacrylamide gel electrophoresis), western blot, and liquid chromatography–mass spectrometry.Results: The proteins that have molecular weight(MW) 43 and 34 k Da were the antigenic protein. Computational bioinformatic analysis by Mascot Server revealed seven novel hypothetical proteins(MW: 43 k Da) and two novel hypothetical proteins(MW:34 k Da). Further analysis(BLASTP, antigenicity, epitope mapping, and specificity analysis) showed that two novel proteins were identified as apolipoprotein D and cathepsin D in Anopheles darlingi.Conclusions: The identified proteins are potential to be developed as a biomarker of mosquito bite's exposure.

Characterization of the salivary microbiome in healthy Thai children

Objective: To investigate the composition of the salivary microbiome of 50 healthy Thai children. Methods: A total 76 provinces in Thailand are grouped into 5 geographical clusters based on unique economics, foods and lifestyles. Geographical locations and the results of an oral assessment were also considered. Genomic DNA was extracted from stimulated saliva samples. Subsequently, amplicon libraries were prepared by 16 S Metagenomic Sequencing Library Preparation. The amplicons were sequenced using an Illumina Miseq platform followed by bioinformatics and statistical analyses.Results: The correlation between oral hygiene status and caries history varied from r^2=0.887 to r^2=0.999 in the geographical groups, suggesting oral hygiene status a strong association between caries history. Twenty taxonomic groups were found in all subjects and constituted 93.6%-96.5% of the microbiome. Of these, genus Veillonella and Prevotella showed significant differences in their proportions between the geographical groups(P<0.05). Furthermore, the proportion of Veillonella parvula, as well as Rothia aeria and Rothia dentocariosa tended to increase with worse oral hygiene status, which was also related to higher dental caries history.Conclusions: The differences in the salivary microbiome as related to geographic regions suggest that environmental factors, which may include dietary habits, could influence the predominant bacteria found in the mouth of Thai children, especially the genus Veillonella and Prevotella. The ratio of Veillonella parvula, Rothia aeria and Rothia dentocariosa may be indicators of worse oral hygiene status and future caries in this population.

Diagnostic model of saliva protein finger print analysis of patients with gastric cancer

AIM:To explore the method for early diagnosis of gastric cancer by screening the expression spectrum of saliva protein in gastric cancer patients using mass spectrometry for proteomics.METHODS:Proportional peptide mass fingerprints were obtained by analysis based on proteomics matrix-assisted laser desorption ionization time-of-flight/mass spectrometry.A diagnosis model was established using weak cation exchange magnetic beads to test saliva specimens from gastric cancer patients and healthy subjects.RESULTS:Significant differences were observed in the mass to charge ratio(m/z) peaks of four proteins(1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da) between gastric cancer patients and healthy subjects.CONCLUSION:The finger print mass spectrum of saliva protein in patients with gastric cancer can be established using gastric cancer proteomics.A diagnostic model for distinguishing protein expression mass spectra of gastric cancer from non-gastric-cancer saliva can be established according to the different expression of proteins 1472.78 Da,2936.49 Da,6556.81 Da and 7081.17 Da.The method for early diagnosis of gastric cancer is of certain value for screening special biological markers.

A magnetic nanoparticles-based method for DNA extraction from the saliva of stroke patients

C677T polymorphism in the methylenetetrahydrofolate reductase （MTHFR） gene is a risk factor for stroke, suggesting that widespread detection could help to prevent stroke. DNA from 70 stroke pa- tients and 70 healthy controls was extracted from saliva using a magnetic nanoparticles-based method and from blood using conventional methods. Real-time PCR results revealed that the C677T polymorphism was genotyped by PCR using DNA extracted from both saliva and blood samples. The genotype results were confirmed by gene sequencing, and results for saliva and blood samples were consistent. The mutation TT genotype frequency was significantly higher in the stroke group than in controls. Homocysteine levels were significantly higher than controls in both TT genotype groups. Therefore, this noninvasive magnetic nanoparticles-based method using saliva samples could be used to screen for the MTHFR C677T polymorphism in target populations.