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At present, even if the education on hard-working spirit has been emphasized increasingly as an important part of practical education in China's education policy, the reality is still far from satisfactory, because many parents do not provide their children with sufficient opportunities to do housework. Previous studies have indicated that the empirical analysis remains to be improved in terms of the relationship between housework and the development of primary and junior high school students. Based on data from the 2020 Monitoring of Students' Academic Quality in Basic Education in Jiangsu Province Study, this study investigates the influence of primary and secondary school students' participation in housework on academic performance by using OLS regression and Coarsened Exact Matching (CEM). The results show that the current proportion of primary and junior high school students involved in housework is not high; however, participating in housework frequently will positively affect the academic performance of primary and junior high school students. Participation in housework in primary school has a greater positive impact on academic performance than that in junior high school. In addition, since excessive academic burden is the main factor hindering primary and junior high school students from being involved in housework, it is necessary to strengthen the publicity of education on hard-working spirit to help people know its importance. Also, we suggest the burden on schoolwork should be reduced to in order to promote more diversified housework related educational opportunities for students.

To elucidate the influence of rape straw returning on soil reducibility and to understand its effects on rice growth and yield in rape‐rice rotation system, 3 years field experiment with 8 treatments of straw incorporation carried out at Mianyang Sichuan Province of China. Results showed that the lowest RCEh value founded at 14–18 d after rice planting; With the increasing of rape straw incorporation, the amount of root (number, weight and length) and root bleeding intensity both increased significantly during 27–32 d after rice planting; 0–20 d are the fast decomposing period of rape straw in rice field. At 10–22 d after rice planting, there is negative correlation between rice root growth and soil reducibility and a negative correlation between rice root and straw incorporation. Oil seed rape straw returning into soil, either by mulching or by ploughing, make the soil more reducible with lower Eh and higher content of reducing material, Fe2+ and hinder the growth of rice root with lower amount (length, weight and number) and bleeding density during this period. Comparing with other straw returning methods, straw returning by ploughing method with the rape straw of 3.0 t/hm2 is more suitable in rice‐rape rotation farms where is convenient for mechanical operation. [ABSTRACT FROM AUTHOR]

Fluorescent dissolved organic matter (FDOM) components were identified by Parallel Factor Analysis (PARAFAC) in surface water of Daliao River and its estuary with a focus on terrestrial humic substance-(HS)-like FDOM identified under two contrasting hydrological conditions. The hydrological conditions did not have noticeable effect on the spectral features of the terrestrial HS-like FDOM, but did affect the components' intensities and photoreactivity: (1) the intensities of terrestrial HS-like components were higher in the normal flow period than in the high flow period, and (2) a spectrally similar terrestrial HS-like FDOM identified under the two contrasting hydrological conditions showed distinct photoreactivity to the same dose of UVA illumination. The findings indicated that terrestrial HS was generated at lower intensities at the terrestrial sources during the high flow period than during the normal flow period and that the transport of terrestrial HS material through the river-estuary system was affected dominantly by seawater dilution along the salinity gradient while fine-tuned by solar UVA illumination. This study exemplifies the effect of hydrological conditions on optical signatures of terrestrial HS-like FDOM and their photoreactivity towards UVA illumination, improving our understanding of the dynamics of terrestrial HS material in river-estuary systems in the framework of the currently proposed new conceptual model for terrestrial organic matter. [ABSTRACT FROM AUTHOR]

Cytokines play an important role in the pathogenesis of hypertension. The authors hypothesized that interleukin 17 (IL-17) might contribute to the prehypertensive state. This study evaluated the relationship between serum levels of IL-17 and prehypertension. A total of 394 participants were enrolled, after excluding for hypertension or treated hypertension, and divided into two groups (optimal blood pressure [BP] and prehypertension) based on the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure classification of BP. Optimal BP was defined as systolic BP <120 mm Hg and diastolic BP <80 mm Hg. Prehypertension was defined as systolic BP of 120 to 139 mm Hg or diastolic BP of 80 to 89 mm Hg. IL-17A levels were determined by enzyme-linked immunosorbent assay. The mean serum IL-17 concentration in the prehypertension group was significantly higher than in the optimal BP group. The cohort was divided into quartiles Q1 (≤3.5 ng/L), Q2 (3.60 to 6.10 ng/L), Q3 (6.20 to 10.00 ng/L), and Q4 (≥10.10 ng/L) based on IL-17 levels. The Q2 to Q4 groups had increasing odds ratios for having prehypertension compared with the Q1 group. Elevated serum IL-17 was accompanied by a rise in systolic BP. Thus, increased serum IL-17 levels are associated with prehypertension. [ABSTRACT FROM AUTHOR]

The widespread use of antibiotics in large-scale livestock production has led to serious antibiotic resistance. Proteus mirabilis is an important pathogenic bacterium on large-scale farms. Chromosomally localized mobilizable genetic elements (genomic islands) and mobile genetic elements (Tn7-like transposons) play an important role in the acquisition and transmission of resistance genes by P. mirabilis. To study the prevalence and resistance characteristics of antibiotic-resistant genomic islands in P. mirabilis of animal origin in China, we performed whole genome sequencing of P. mirabilis isolated from large-scale pig and chicken farms. Three new variants of PmGRI1 (HN31, YN8, and YN9), and a hybrid structure (HN2p) formed by the multidrug-resistant Tn7-like-HN2p transposon and a genomic island PmGRI1-HN2p, were identified from P. mirabilis. All variants underwent homologous recombination mediated by insertion sequence IS26. A genomic rearrangement in the chromosome between the Tn7-like-HN2p transposon and PmGRI1-HN2p occurred in HN2p. The heterozygous structure contained various antimicrobial resistance genes, including three copies of fluoroquinolone resistance gene qnrA1 and 16S rRNA methylase gene rmtB, which are rarely found in P. mirabilis. Our results highlight the structural genetic diversity of genomic islands by characterizing the novel variants of PmGRI1 and enrich the research base of multidrug resistance genomic islands. [ABSTRACT FROM AUTHOR]

Dehydrins (DHN) belong to the late embryogenesis abundant II family and have been found to enhance plant tolerance to abiotic stress. In the present study, we reported four DHNs in Larix kaempferi (LkDHN) which were identified from the published transcriptome. Alignment analysis showed that these four LkDHNs shared close relationships and belonged to SK3-type DHNs. The electrophoretic mobility shift assay indicated that these four LkDHNs all possess sequence-independent binding capacity for double-strands DNAs. The subcellular localizations of the four LkDHNs were in both the nucleus and cytoplasm, indicating that these LkDHNs enter the nucleus to exert the ability to bind DNA. The preparation of tobacco protoplasts with different concentrations of mannitol showed that LkDHNs enhanced the tolerance of plant cells under osmotic stress. The overexpression of LkDHNs in yeasts enhanced their tolerance to osmotic stress and helped the yeasts to survive severe stress. In addition, LkDHNs in the nucleus of salt treated tobacco increased. All of these results indicated that the four LkDHNs help plants survive from heavy stress by participating in DNA protection. These four LKDHNs played similar roles in the response to osmotic stress and assisted in the adaptation of L. kaempferi to the arid and cold winter of northern China. [ABSTRACT FROM AUTHOR]

Drought is one of the major factors limiting rice yield worldwide. A total of 46 hybrid rice varieties were chosen to investigate their root distribution and their response to drought. A field experiment was carried out in a dry shed building to evaluate the drought tolerance capacity of hybrid rice varieties on the basis of CTIRDE (complex tolerance index of rice under drought environment) values. Next, the experiment was conducted in a specially designed pot system and seed bags to analyze the root distribution and activity of antioxidant enzymes in different rice varieties. Moreover, the DEEPER ROOTING 1 (DRO1) gene was sequenced to elucidate its role in the root distribution of typical rice varieties. On the basis of CTIRDE values, the 46 hybrid rice varieties were classified as tolerant (CTIRDE ≥ 0.75), semi-tolerant (0.75 > CTIRDE > 0.65), or sensitive (CTIRDE ≤ 0.65) to drought stress. The tolerant varieties (Chuanguyou208 and Deyou4727) displayed a significantly larger length, had higher number and weight of roots in the 30–50 cm soil layer, and exhibited a significantly higher activity of Superoxide dismutase (SOD) and Peroxidase (POD) enzymes in roots during the drought stress period. The DRO1 gene sequencing results revealed that the tolerant and sensitive varieties exhibited a single-nucleotide polymorphism (SNP) in the 3-exon region, and the tolerant varieties (Chuanguyou208 and Deyou4727) exhibited a larger root growth angle with the horizontal axis, hence developing a deeper root system as compared with the other two group varieties. A significant correlation was found not only between the DRO1 gene and root distribution but also between DRO1 and the activity of SOD and POD enzymes. Conclusively, as a key feature, a deep root system enabled tolerant rice varieties (Chuanguyou208 and Deyou4727) to avoid drought stress by absorbing more water stored in deep soil layers. The root distribution, activity of POD and SOD enzymes in roots, and DRO1 gene can be used to screen tolerant rice varieties that can survive better under drought stress during the seedling stage of rice growth. [ABSTRACT FROM AUTHOR]

• Water use indicators of wheat production were modelled at high spatial resolution. • Irrigation in water-scarce northern regions caused the larger environmental impacts. • Hotspot regions accounted for 34% of the cropping area but 61% of irrigation. • Paradoxically, gains in total water efficiency have led to increased water scarcity. Water shortage is a critical constraint limiting China's capacity for food security. To provide evidence supporting environmentally sustainable water use in food production, this study compared irrigation water productivities (IWPs) and water-scarcity footprints (WSFs) for China's wheat production at high spatial resolution. Contrary to previous water productivity studies assessing crop yield over total water consumption, it was found that IWPs in China's water-scarce northern regions were much lower than those in water-rich southern regions. The WSFs further demonstrated the larger environmental impacts resulting from irrigation in water-scarce northern regions. Hotspot regions, having IWPs in the lowest tercile (<5.2 kg m−3) and WSFs in the highest tercile (>0.058 m3 H 2 O e kg − 1), were mainly located in the Huang-Huai-Hai and northwestern regions and accounted for 34% of the cropping area but 61% of irrigation water use. Historically, the south was also an important contributor of China's wheat production, but progressive shifts toward highly resource-efficient cropping in the Huang-Huai-Hai region has occurred. The paradox is that gains in total crop water efficiency have led to increased irrigation demand and water scarcity. Today, croplands suitable for wheat production lie fallow in some southern regions in the winter. A national reassessment of this situation is urgently needed. [ABSTRACT FROM AUTHOR]

Objective: To explore the feasible and cost-effective intervention strategies to achieve the goal of dynamic COVID-Zero in China., Design: A Susceptible-Exposed-Infectious-Recovered model combined economic evaluation was used to generate the number of infections, the time for dynamic COVID-Zero and calculate cost-effectiveness under different intervention strategies. The model simulated the 1 year spread of COVID-19 in mainland China after 100 initial infections were imported., Interventions: According to close contact tracing degree from 80% to 100%, close contact tracing time from 2 days to 1 day, isolation time from 14 days to 7 days, scope of nucleic acid testing (NAT) from 10% to 100% and NAT frequency from weekly to every day, 720 scenarios were simulated., Outcome Measure: Cumulative number of infections (CI), social COVID-Zero duration (SCD), total cost (TC) and incremental cost-effectiveness ratio., Results: 205 of 720 scenarios could achieve the total COVID-Zero since the first case was reported. The fastest and most cost-effective strategy was Scenario 680, in which all close contacts were traced within 1 day, the isolation time was 14 days and 10% of the national population was randomly checked for NAT every day. In Scenario 680, the CI was 280 (100 initial infections) and the SCD was 13 days. The TC was ¥4126 hundred million and the cost of reducing one infection was ¥47 470. However, when the close contact tracing time was 2 days and the degree of close contact tracing was 80%-90%, the SCD would double to 24-101 days and the TCs increased by ¥16 505 to 37 134 hundred million compared with Scenario 680., Conclusions: If all close contact was controlled within 1 day, the rapid social COVID-Zero can be achieved effectively and cost-effectively. Therefore, the future prevention and control of emerging respiratory infectious diseases can focus on enhancing the ability of close contact tracing., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

China is facing a serious urban regeneration issue in which replicable international-style locations are losing their socio-cultural adaptability, especially in anonymous residential neighbourhoods. This study defines the key location qualities from local literature and then refines these qualities through observation investigations and statistical analysis ( n = 180) to establish links between theories and contemporary uses. Based on the results, a correlation analysis of local place qualities was assessed from users' perceptions ( n = 180) to identify the interactional influences between each indicator of local place qualities. Finally, local place qualities were scored to address their level of impact on users' perceptions. The results highlighted health, enjoyment, and social dependence as the most concerning factors in site investigations based on local cognitions. They are strongly associated with key local place qualities (naturality, functionality, cosmological cognitions, and interdependent sociability), directly and indirectly resulting in different levels of impact on users' perceptions at different scales.

Background: Imported COVID-19 patients posed great challenges to border areas' COVID-19 control. However, research was scarce to reveal epidemiological characteristics of COVID-19 in border areas. This study aimed to explore the detailed transmission chains, and reveal epidemiological and clinical characteristics of the largest COVID-19 outbreak caused by Delta variant of concern (VOC) occurred in the China-Myanmar border area., Methods: During the outbreak from July to September, 2021 in Ruili City, Yunnan Province, China, epidemiological investigation data and clinical-related data pertaining to confirmed COVID-19 patients were collected. Patients' contact history data and viral gene sequencing were used for inference of transmission chains. Sociodemographic and epidemiological characteristics, cycle threshold (Ct) value, and antibodies level were compared between patients who were vaccinated against COVID-19 or not., Results: A total of 117 COVID-19 patients were confirmed during the outbreak, among which 86 (73.5%) were breakthrough infections. These patients evenly split between Chinese and Myanmar people (50.4% vs. 49.6%). Most of these patients were mild (45.3%) or moderate (48.7%) infections with no death reported. Multi-source of infection led to 16 transmission chains with a maximum of 45 patients in one chain. Patients vaccinated against COVID-19 before infection had relatively higher antibodies (IgM and IgG) levels and more rapid response to infection than non-vaccinated patients ( p < 0.05)., Conclusion: Land border areas have greater risks of imported COVID-19 and more complicated epidemics. It should be cautious in formulating entry and exit requirements for border areas. The immune effect of COVID-19 vaccines and related mechanism should be further explored., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yan, Hao, Wang, Wang, Zhang, Li, Jia, Chang, Zhang and Shui.)

The pathogenic variants in KCNQ4 cause DFNA2 nonsyndromic hearing loss. However, the understanding of genotype-phenotype correlations between KCNQ4 and hearing is limited. Here, we identified a novel KCNQ4 mutation p.G228D from a Chinese family, including heterozygotes characterized by high-frequency hearing loss that is progressive across all frequencies and homozygotes with more severe hearing loss. We constructed a novel murine model with humanized homologous Kcnq4 mutation. The heterozygotes had mid-frequency and high-frequency hearing loss at 4 weeks, and moved toward all frequencies hearing loss at 12 weeks, while the homozygotes had severe-to-profound hearing loss at 8 weeks. The degeneration of outer hair cells (OHCs) was observed from basal to apical turn of cochlea. The reduced K + currents and depolarized resting potentials were revealed in OHCs. Remarkably, we observed the loss of inner hair cells (IHCs) in the region corresponding to the frequency above 32 kHz at 8-12 weeks. The results suggest the degeneration of OHCs and IHCs may contribute to high-frequency hearing loss in DFNA2 over time. Our findings broaden the variants of KCNQ4 and provide a novel mouse model of progressive hearing loss, which contributes to an understanding of pathogenic mechanism and eventually treatment of DFNA2 progressive hearing loss., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Prevention and control of HIV/AIDS and other sexually transmitted diseases (STDs) are major public health priorities in China, but are influenced by the COVID-19 epidemic. In this study, we aimed to quantitatively explore the impact of the COVID-19 epidemic and its control measures on five major STD epidemics in China. Methods: A monthly number of newly reported cases of HIV/AIDS, hepatitis B and C, gonorrhea, and syphilis from January 2010 to December 2020 were extracted to establish autoregressive integrated moving average (ARIMA) models. Each month's absolute percentage error (APE) between the actual value and model-predicted value of each STD in 2020 was calculated to evaluate the influence of the COVID-19 epidemic on the STDs. Pearson correlation analysis was conducted to explore the confirmed COVID-19 case numbers and the COVID-19 control measures' correlations with the case numbers and the APEs of five STDs in 2020. Results: The actual number of five STDs in China was more than 50% lower than the predicted number in the early days of the COVID-19 epidemic, especially in February. Among them, the actual number of cases of hepatitis C, gonorrhea, and syphilis in February 2020 was more than 100% lower than the predicted number (APE was -102.3, -109.0, and -100.4%, respectively). After the sharply declines of STDs' reported cases in early 2020, the case numbers recovered quickly after March. The epidemic of STDs was negatively associated with the COVID-19 epidemic and its control measures, especially for restrictions on gathering size, close public transport, and stay-at-home requirements ( p < 0.05). Conclusion: COVID-19 had a significant but temporary influence on the STD epidemic in China. The effective control of COVID-19 is vital for STD prevention. STD services need to be improved to prevent STDs from becoming a secluded corner in the shadow of COVID-19., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yan, Wang, Zhang, Wang, Zhang and Jia.)

Objective: To establish a model to predict gestational diabetes mellitus (GDM) based on the clinical characteristics, early pregnancy (10-12 weeks gestation) peripheral blood routine, and biochemical indicators, and to explore its predictive efficiencies., Methods: Data from 607 pregnant women with GDM were compared to the data from 833 pregnant women without GDM admitted to the Obstetrics Department of Fujian Maternity and Child Health Hospital (affiliated to Fujian Medical University) from May 2018 to December 2018 were retrospectively included. The ages of the pregnant women, paternal ages, number of pregnancies, number of deliveries, pre-pregnancy heights/weights, and the calculated body mass indexes (BMI) were recorded. In all participants, 10-12 weeks of pregnancy, afamin concentration, routine blood work, prenatal aneuploidy screening, and biochemical testing were performed. At weeks 24-28 of gestation, patients underwent oral glucose tolerance test (OGTT) for GDM screening., Results: Multivariate logistic regression analysis showed that maternal age, early pregnancy afamin level, triglycerides, and platelet/lymphocyte ratio (PLR) were independent risk factors for gestational diabetes. The formula for predicting GDM probability was as follows: P = 1/1 + exp ( - 6.054 + 0.774 × triglycerides + 0.002 × afamin + 0.155 × age - 0.012 × PLR )]. From the established ROC curve, the area under the curve (AUC) was 0.748, indicating that the model has a good degree of discrimination. When the predictive probability cut-off value was set on 0.358, sensitivity, specificity, positive predictive value, and negative predictive value were 69.2%, 68.3%, 42.5%, and 86.2%, respectively, and the accuracy rate was 70.2%. The Hosmer-Lemeshow test results showed that the goodness of the model fit has a good calibration ability (χ2 = 12.269, df=8, P=0.140)., Conclusions: Maternal age, early pregnancy afamin level, triglycerides, and PLR are independent risk factors for gestational diabetes. When combined, the above indicators are helpful for prediction, early diagnosis, and intervention of gestational diabetes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Wang, Zheng, Yan, Xu, Xu, Zheng, Xu and Lin.)

Background: Previous studies found that lactate dehydrogenase (LDH) levels predicted poor outcomes in hemorrhagic stroke, but the prognostic role of LDH in ischemic stroke (IS) remains unclear. The aim of this study is to investigate the association between LDH and adverse clinical outcomes in patients with acute ischemic stroke (AIS) or transient ischemic attack (TIA)., Methods: All patients were enrolled from the Third China National Stroke Registry (CNSR-III). Adverse outcomes included all-cause death and poor functional outcomes [defined as modified Rankin Scale (mRS) score 3-6 and 2-6] at 3 months and 1 year. Multivariable Cox proportional hazards models and logistic regressions were used to evaluate the association of LDH with risk of all-cause death and poor functional outcomes, respectively., Results: Among 9,796 included patients, the median [interquartile range (IQR)] of LDH was 175.00 (151.00-205.40) U/L. After adjustment for confounding factors, patients in the highest LDH quartile had a higher risk of all-cause death [hazard ratio (HR), 2.23; 95% confidence interval (CI), 1.27-3.90], and a higher proportion of mRS score 3-6 [odds ratio (OR), 1.54; 95% CI, 1.26-1.90] and mRS score 2-6 (OR, 1.56; 95% CI, 1.32-1.84) at 3 months. We also observed a J-shaped association between LDH and risk of each outcome. Consistent results were found at 1 year., Conclusions: Higher LDH levels are independently associated with adverse outcomes in patients with AIS or TIA.

Objectives: This study aimed to determine the genetic environment of antimicrobial resistance genes in Proteus mirabilis strain STP3 isolated from a diarrhoeic pig on a swine farm in Sichuan Province, China., Methods: Strain STP3 was subjected to antimicrobial susceptibility testing. Illumina MiSeq (200× coverage) and Nanopore PromethION (100× coverage) platforms were used for genome sequencing. A conjugation experiment was performed to determine the transferability and stability of antimicrobial resistance genes in this strain., Results: The assembled circular genome of P. mirabilis STP3 was 4 115 975 bp with a GC content of 39.58%; no plasmid sequence was detected. A novel genomic resistance island (PmGRI1-STP3) and an SXT/R391 integrative conjugative element (ICE) variant (ICEPmiChnSTP3) were characterised in P. mirabilis STP3. PmGRI1-STP3 of 52.7 kb was located at the 3' end of tRNA-Sec and shared the greatest identity with PmGRI1-C55 (54% coverage, 99.99% identity). PmGRI1-STP3 carried 16 resistance genes, including the clinically important extended-spectrum β-lactamase (ESBL) gene bla CTX-M-3 . ICEPmiChnSTP3 was inserted into the prfC gene. It carried 18 resistance genes, including the rRNA methyltransferase gene cfr and the fluoroquinolone resistance gene aac(6')-Ib-cr. A class 2 integron (dfrA1-sat2-aadA1) was also identified on transposon Tn7. Mobilisation experiments indicated that ICEPmiChnSTP3 was conjugally mobilised to Escherichia coli. However, PmGRI1-STP3 appeared to lose its mobilisation ability., Conclusion: The identification of two genomic islands (GIs) in this study suggested that genetic elements might be key mediators for resistance gene acquisition in P. mirabilis and that IS26-mediated rearrangements promote the diversity of GIs., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Study suggested that elevated homocysteine showed a multiplicative effect on cardiovascular diseases in hypertensive subjects. It was reported that elevated homocysteine level was independently associated with increased arterial stiffness in prehypertensives. It remains unclear whether prehypertensives combined with elevated homocysteine have adverse cardiovascular risk factors. We aimed to compare cardiometabolic risk profile between prehypertensives with hyperhomocysteinaemia and those without either condition., Methods: Plasma total homocysteine and risk profile were determined among 874 Chinese non-hypertension individuals in Tianjin. They were subdivided into four groups: prehypertension with hyperhomocysteinaemia (≥10 μmol/L), prehypertension with normal homocysteine (<10 μmol/L), normotension with hyperhomocysteinaemia, normotension with normol homocysteine, respectively., Results: In 874 participants, 22.5% of them were male, mean age was 56.8 years. In multiple comparisons, after adjustment for age, gender, smoking, alcohol, exercise, education prehypertensives had higher body mass index (BMI) and high sensitive C reactive protein (hs-CRP) than normotensives (p < 0.05, respectively); Only prehypertensive subjects with hyperhomocysteinaemia had higher triglyceride and serum uric acid compared to normotensive subjects, and lower HDL cholesterol than normotensives with normal homocysteine (p < 0.05, respectively). However, the significance of higher hs-CRP, uric acid and lower HDL cholesterol were abolished when further adjustment was made for BMI., Conclusion: The combination of prehypertension and hyperhomocusteinaemia increases the likelihood of having adverse cardiometabolic risk profile. Strict lipid management and weigh control may be needed in prehypertensives with elevated homocysteine.