Antimony-Platinum Modulated Contact Enabling Majority Carrier Polarity Selection on a Monolayer Tungsten Diselenide Channel.

We develop a novel metal contact approach using an antimony (Sb)-platinum (Pt) bilayer to mitigate Fermi-level pinning in 2D transition metal dichalcogenide channels. This strategy allows for control over the transport polarity in monolayer WSe2 devices. By adjustment of the Sb interfacial layer thickness from 10 to 30 nm, the effective work function of the contact/WSe2 interface can be tuned from 4.42 eV (p-type) to 4.19 eV (n-type), enabling selectable n-/p-FET operation in enhancement mode. The shift in effective work function is linked to Sb-Se bond formation and an emerging n-doping effect. This work demonstrates high-performance n- and p-FETs with a single WSe2 channel through Sb-Pt contact modulation. After oxide encapsulation, the maximum current density at |VD| = 1 V reaches 170 µA/µm for p-FET and 165 µA/µm for n-FET. This approach shows promise for cost-effective CMOS transistor applications using a single channel material and metal contact scheme.

Mindsets of suicide trajectories: An Linguistic Inquiry and Word Count analysis of suicide hotline conversations.

OBJECTIVE: The aim of the study was to explore the psychological characteristics of the individuals with various suicide risks using computerized text analysis, in the hopes of a better understanding of suicide trajectories. METHODS: 627 first-time callers' records were randomly selected from Taiwan An-Shin Hotline database between 2013 and 2018. The voice records were evaluated by two psychologists to determine the levels of suicide risk (156 with uncertainty of risk, 177 with low suicidal ideation, 157 with high suicidal ideation, and 137 with suicide preparation/attempt) and transcribed into text. The Linguistic Inquiry and Word Count 2015 (LIWC2015) program combined with Chinese dictionary were then used to calculate the frequency of word categories. RESULTS: Exploratory factor analysis identified four mindsets of language characteristics, named "opposition and questioning", "active engagement", "negative rumination", and "focus on death". Psychological descriptions of the mindsets were also obtained through correlation analysis with the LIWC2015 categories and indicators. The four mindsets effectively distinguished the callers with different levels of suicide risk. CONCLUSION: The psychological characteristics of people with various suicide risks can be described and differentiated via the closed-word categories and composite indicators. These results provide useful information for practitioners and researchers.

Targeting the CDK7-MDK axis to suppresses irinotecan resistance in colorectal cancer.

AIMS: Colorectal cancer (CRC) remains a major global health issue, with metastatic cases presenting poor prognosis despite advances in chemotherapy and targeted therapy. Irinotecan, a key drug for advanced CRC treatment, faces challenges owing to the development of resistance. This study aimed to understand the mechanisms underlying irinotecan resistance in colorectal cancer. MAIN METHODS: We created a cell line resistant to irinotecan using HT29 cells. These resistant cells were utilized to investigate the role of the CDK7-MDK axis. We employed bulk RNA sequencing, conducted in vivo experiments with mice, and analyzed patient tissues to examine the effects of the CDK7-MDK axis on the cellular response to irinotecan. KEY FINDINGS: Our findings revealed that HT29 cells resistant to irinotecan, a crucial colorectal cancer medication, exhibited significant phenotypic and molecular alterations compared to their parental counterparts, including elevated stem cell characteristics and increased levels of cytokines and drug resistance proteins. Notably, CDK7 expression was substantially higher in these resistant cells, and targeting CDK7 effectively decreased their survival and tumor growth, enhancing irinotecan sensitivity. RNA-seq analysis indicated that suppression of CDK7 in irinotecan-resistant HT29 cells significantly reduced Midkine (MDK) expression. Decreased CDK7 and MDK levels, achieved through siRNA and the CDK7 inhibitor THZ1, enhanced the sensitivity of resistant HT29 cells to irinotecan. SIGNIFICANCE: Our study sheds light on how CDK7 and MDK influence irinotecan resistance in colorectal and highlights the potential of MDK-targeted therapies. We hypothesized that irinotecan sensitivity and overall treatment efficacy would improve by inhibiting MDK. This finding encourages a careful yet proactive investigation of MDK as a therapeutic target to enhance outcomes in colorectal cancer patients.

Lipopolysaccharide-Induced Lysosomal Cell Death Through Reactive Oxygen Species in Rat Liver Cell Clone 9.

In sepsis, bacterial components, particularly lipopolysaccharide (LPS), trigger organ injuries such as liver dysfunction. Although sepsis induces hepatocyte damage, the mechanisms underlying sepsis-related hepatic failure remain unclear. In this study, we demonstrated that the LPS-treated rat hepatocyte cell line Clone 9 not only induced reactive oxygen species (ROS) generation and apoptosis but also increased the expression of the autophagy marker proteins LC3-II and p62, and decreased the expression of intact Lamp2A, a lysosomal membrane protein. Additionally, LPS increased lysosomal membrane permeability and galectin-3 puncta formation, and promoted lysosomal alkalization in Clone 9 cells. Pharmacological inhibition of caspase-8 and cathepsin D (CTSD) suppressed the activation of caspase-3 and rescued the viability of LPS-treated Clone 9 cells. Furthermore, LPS induced CTSD release associated with lysosomal leakage and contributed to caspase-8 activation. Pretreatment with the antioxidant N-acetylcysteine (NAC) not only diminished ROS generation and increased the cell survival rate, but also decreased the expression of activated caspase-8 and caspase-3 and increased the protein level of Lamp2A in LPS-treated Clone 9 cells. These results demonstrate that LPS-induced ROS causes lysosomal membrane permeabilization and lysosomal cell death, which may play a crucial role in hepatic failure in sepsis. Our results may facilitate the development of new strategies for sepsis management.

Development of a long-term care service integration self-assessment tool.

The World Health Organization emphasizes the importance of providing integrated care for older people. Taiwan is the fastest aging country in the world. In 2016, Taiwan implemented the Long-Term Care Plan 2.0 (TLTCP 2.0), aimed at providing integrated long-term care (LTC) services in communities. However, LTC service agencies have not been able to evaluate the level of integrated care they provide due to the lack of an effective assessment tool. To address this need, this study sets out to develop an integration assessment tool, namely the Self-Assessment for Service Integration in Long-Term Care (SASI-LTC), which will allow LTC agencies to self-evaluate their current level of integration from multiple perspectives. The SASI-LTC was developed based on Evashwick's framework, underwent two rounds of Delphi panels with twenty-six experts, and a pilot test with 243 valid questionnaires from administrators of Tier A agencies who are responsible for integrating LTC. The Delphi experts assessed the content with high levels of agreement using medians, the scale content validity index (SCVI) and item content validity index (ICVI). The SASI-LTC included four domains (inter-entity organization and management, integrated care coordination, integrated resources, and integrated information systems) with thirty items. The SASI-LTC showed good reliability (Cronbach's α = 0.94) and good validity, and a confirmatory factor analysis showed a good model fit index [χ2/df = 1.38; RMSEA = 0.040; CFI = 0.963; SRMR = 0.049] in pilot testing. While the SASI-LTC is a useful and feasible tool for Taiwan's LTC service agencies to evaluate their level of integration in providing LTC services, it could also be used in other countries with minor adjustments to localization of items related to financial integration.

Associations Between Obstructive Sleep Apnea Syndrome, Dry Eye Disease, and CPAP Usage Among Taiwanese Patients: A Retrospective Analysis.

Study Objectives: To evaluate the association between obstructive sleep apnea (OSA) and dry eye disease (DED) and analyze the impact of Continuous Positive Airway Pressure (CPAP) on DED. Methods: This is a retrospective population-based case-control study. Patients who underwent polysomnography in Taiwan from March 1, 2009, to March 1, 2020, were identified from the database of a sleep center. Patients who were diagnosed with keratoconjunctivitis sicca or tear film insufficiency were included. Patients without data from Schirmer's test, lacking tear break-up time values, or with a history of refractive surgery, Sjögren's syndrome, ocular injuries, or a disability in eyelid closure were excluded. All patients with DED enrolled had DED in both eyes. OSA severity between patients with and without DED was compared. Results: In total, 86 patients with DED and 86 age-matched patients without DED were enrolled. Significant differences in apnea-hypopnea index values (patients with DED: 29.1 ± 23.4, patients without DED: 17.9 ± 20.2, P < 0.001), OSA severity (P < 0.001), and lowest oxygen saturation (P = 0.040) between patients with and without DED were observed. A multivariate logistic regression model indicated that the use of CPAP was independently associated with DED after adjustments for OSA severity. Patients undergoing CPAP were at greater risk of developing DED than those not undergoing CPAP (Odds ratio: 3.93, 95% confidence interval: 1.47-10.49, P = 0.006). Conclusion: OSA severity is associated with DED and might be attributed to the use of CPAP.

Recurrent Occupational Hantavirus Infections Linked to Feeder Rodent Breeding Farm, Taiwan, 2022.

We investigated 2 acute cases and 1 previous case of Seoul hantavirus infection in workers in a feeder rodent breeding farm in Taiwan. Prevalence of hantavirus IgG among the tested feeder rats was 37.5%. Appropriate prevention measures, including using disinfection protocols and personal protective equipment, are crucial to lowering risk.

Topology Optimization Enables High-Q Metasurface for Color Selectivity.

Nonlocal metasurfaces, exemplified by resonant waveguide gratings (RWGs), spatially and angularly configure optical wavefronts through narrow-band resonant modes, unlike the broad-band and broad-angle responses of local metasurfaces. However, forward design techniques for RWGs remain constrained at lower efficiency. Here, we present a topology-optimized metasurface resonant waveguide grating (MRWG) composed of titanium dioxide on a glass substrate capable of operating simultaneously at red, yellow, green, and blue wavelengths. Through adjoint-based topology optimization, while considering nonlocal effects, we significantly enhance its diffraction efficiency, achieving numerical efficiencies up to 78% and Q-factors as high as 1362. Experimentally, we demonstrated efficiencies of up to 59% with a Q-factor of 93. Additionally, we applied our topology-optimized metasurface to color selectivity, producing vivid colors at 4 narrow-band wavelengths. Our investigation represents a significant advancement in metasurface technology, with potential applications in see-through optical combiners and augmented reality platforms.

Two glycosyl transferase 2 genes from the gram-positive bacterium Clostridium ventriculi encode (1,3;1,4)-ß-D-glucan synthases.

The exopolysaccharides of the Gram-positive bacterium Romboutsia ilealis have recently been shown to include (1,3;1,4)-ß-D-glucans. In the present study, we examined another Clostridia bacterium Clostridium ventriculi that has long been considered to contain abundant amounts of cellulose in its exopolysaccharides. We treated alcohol insoluble residues of C. ventriculi that include the exopolysaccharides with the enzyme lichenase that specifically hydrolyses (1,3;1,4)-ß-D-glucans, and examined the oligosaccharides released. This showed the presence of (1,3;1,4)-ß-D-glucans, which may have previously been mistaken for cellulose. Through genomic analysis, we identified the two family 2 glycosyltransferase genes CvGT2-1 and CvGT2-2 as possible genes encoding (1,3;1,4)-ß-D-glucan synthases. Gain-of-function experiments in the yeast Saccharomyces cerevisiae demonstrated that both of these genes do indeed encode (1,3;1,4)-ß-D-glucan synthases.

A Robust α-l-Fucosidase from Prevotella nigrescens for Glycoengineering Therapeutic Antibodies.

Eliminating the core fucose from the N-glycans of the Fc antibody segment by pathway engineering or enzymatic methods has been shown to enhance the potency of therapeutic antibodies, especially in the context of antibody-dependent cytotoxicity (ADCC). However, there is a significant challenge due to the limited defucosylation efficiency of commercially available α-l-fucosidases. In this study, we report a unique α-l-fucosidase (PnfucA) from the bacterium Prevotella nigrescens that has a low sequence identity compared with all other known α-l-fucosidases and is highly reactive toward a core disaccharide substrate with fucose α(1,3)-, α (1,4)-and α(1,6)-linked to GlcNAc, and is less reactive toward the Fuc-α(1,2)-Gal on the terminal trisaccharide of the oligosaccharide Globo H (Bb3). The kinetic properties of the enzyme, such as its Km and kcat, were determined and the optimized expression of PnfucA gave a yield exceeding 30 mg/L. The recombinant enzyme retained its full activity even after being incubated for 6 h at 37 °C. Moreover, it retained 92 and 87% of its activity after freezing and freeze-drying treatments, respectively, for over 28 days. In a representative glycoengineering of adalimumab (Humira), PnfucA showed remarkable hydrolytic efficiency in cleaving the α(1,6)-linked core fucose from FucGlcNAc on the antibody with a quantitative yield. This enabled the seamless incorporation of biantennary sialylglycans by Endo-S2 D184 M in a one-pot fashion to yield adalimumab in a homogeneous afucosylated glycoform with an improved binding affinity toward Fcγ receptor IIIa.

Orbital subperiosteal abscess in adolescents and adults: predictors and outcomes of nonsurgical management and surgical approaches.

PURPOSE: The aim of this study was to assess predictors and outcomes of subperiosteal abscess (SPA) management in adolescents and adults at two tertiary care centers. METHODS: This retrospective cohort study included cases of SPA from January 1 2000 to October 9 2022 at two institutions. Patients 9 years or older were categorized into surgical and nonsurgical cohorts. Surgical subgroups included those who underwent functional endoscopic sinus surgery (FESS) alone, external (transcutaneous or transconjunctival) orbitotomy alone, or combined FESS and external surgery. The presented features were assessed as potential treatment predictors. Outcomes included length of stay (LOS), final best-corrected visual acuity (BCVA), readmission rate, and reoperation rate. RESULTS: Of the 159 SPA cases included, 127 (79.9%) underwent surgery and 32 (20.1%) were managed nonsurgically. The nonsurgical cohort was younger (p = .003) with smaller abscesses (p < .001) that were more likely to be medial (p < .001). The nonsurgical cohort had shorter LOS (p < .001); final BCVA and readmission rates were similarly favorable. Abscess location was correlated with surgical approach. Superior SPA that underwent FESS or external surgery alone had higher reoperation rates (57.1.0% and 58.3%, respectively) than combined (17.9%). External approach and FESS alone resulted in lower reoperation rates (15.4% and 15.0%, respectively) than combined (27.3%) for medial SPA. Subgroup analysis in the sinusitis cohort yielded similar results. CONCLUSIONS: A trial of nonsurgical management may be safe and effective for select patients aged 9 years and older with sinusitis-derived, medial, and small SPA. When surgery is indicated, approach should be guided by abscess location to minimize reoperation risk.

The regulation of intestinal flora on host's genes may play an essential role in the development of endometrial hyperplastic processes in yang deficiency individuals.

Yang-deficiency constitution (YADC) is linked to a higher vulnerability to various diseases, such as cold coagulation and blood stasis (CCBS) syndrome and infertility. Endometrial hyperplastic processes (EHPs) are a leading cause of infertility in women and are characterized by CCBS. However, it remains unclear whether YADC is related to the development of EHPs. METHODS: We recruited 202 EHPs patients including 147 with YADC (YEH group) and 55 with non-YADC (NYEH group). Fecal samples were collected from 8 YEH patients and 3 NYEH patients and analyzed using 16S rRNA V3-V4 sequencing for gut microbiota analysis. We obtained constitution survey data and a differential gut microbiota dataset from the literature for further analysis. Bioinformatics analysis was conducted using gut microbiota-related genes from public databases. RESULTS: YADC was significantly more prevalent in EHPs than non-YADC (P < 0.001), suggesting it as a potential risk factor for EHPs occurrence (ORpopulation survey = 13.471; ORhealthy women = 5.173). The YEH group had higher levels of inflammation, estrogen, and tamoxifen-related flora compared to NYEH and healthy YADC groups. There was an interaction between inflammation, estrogen, differential flora, and EHPs-related genes, particularly the TNF gene (related to inflammation) and the EGFR gene (related to estrogen), which may play a crucial role in EHPs development. CONCLUSION: YEH individuals exhibit significant changes in their gut microbiota compared to NYEH and healthy YADC. The interaction between specific microbiota and host genes is believed to play a critical role in the progression of EHPs.

Development and validation of the Atri-Risk Conduction Index risk score to predict risk of atrial fibrillation after typical atrial flutter ablation.

BACKGROUND: Identification of patients at risk for atrial fibrillation (AF) after typical atrial flutter (tAFL) ablation is important to guide monitoring and treatment. OBJECTIVE: The purpose of this study was to create and validate a risk score to predict AF after tAFL ablation METHODS: We identified patients who underwent tAFL ablation with no AF history between 2017 and 2022 and randomly allocated to derivation and validation cohorts. We collected clinical variables and measured conduction parameters in sinus rhythm on an electrophysiology recording system (CardioLab, GE Healthcare). Univariate and multivariate logistic regressions (LogR) were used to evaluate association with AF development. RESULTS: A total of 242 consecutive patients (81% male; mean age 66 ± 11 years) were divided into derivation (n =142) and validation (n = 100) cohorts. Forty-two percent developed AF over median follow-up of 330 days. In multivariate LogR (derivation cohort), proximal to distal coronary sinus time (pCS-dCS) ≥70 ms (odds ratio [OR] 16.7; 95% confidence interval [CI] 5.6-49), pCS time ≥36 ms (OR 4.5; 95% CI 1.5-13), and CHADS2-VASc score ≥3 (OR 4.3; 95% CI 1.6-11.8) were independently associated with new AF during follow-up. The Atri-Risk Conduction Index (ARCI) score was created with 0 as minimal and 4 as high-risk using pCS-dCS ≥70 ms = 2 points; pCS ≥36 ms = 1 point; and CHADS2-VASc score ≥3 = 1 point. In the validation cohort, 0% of patients with ARCI score = 0 developed AF, whereas 89% of patients with ARCI score = 4 developed AF. CONCLUSION: We developed and validated a risk score using atrial conduction parameters and clinical risk factors to predict AF after tAFL ablation. It stratifies low-, moderate-, and high-risk patients and may be helpful in individualizing approaches to AF monitoring and anticoagulation.

Prevalence and risk factors for chronic kidney disease among older adult patients with schizophrenia in Taiwan.

OBJECTIVES: There is an increasing incidence and prevalence of patients with chronic kidney disease (CKD) worldwide. Little is known the prevalence of CKD among older patients with schizophrenia. The purpose of this study was to investigate the prevalence of CKD and its risk factors in older adults with schizophrenia. METHODS: In this cross-sectional study, a convenience sample of 240 patients with schizophrenia age 50 or older were recruited. In addition to demographic and clinical data, participants' estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease equation based on age, sex, ethnicity, and serum creatinine level determined from a blood sample taken from participants. RESULTS: The overall prevalence of CKD was 11.3%. Those with CKD group were older, had a longer duration of psychiatric illness, a higher body mass index (BMI), and diagnoses of hypertension compared to those in the non-CKD group. Independent of other risk factors, older age and BMI were significantly associated with CKD. CONCLUSIONS: This study found that the overall prevalence of CKD in older patients with schizophrenia was 11.3%. Risk factors for CKD in this population were older age and higher BMI. In addition to early identification and early treatment of CKD in older patients with schizophrenia, clinicians should actively manage the risk factors identified in this study, such as higher BMI and older age.

Structural basis and synergism of ATP and Na+ activation in bacterial K+ uptake system KtrAB.

The K+ uptake system KtrAB is essential for bacterial survival in low K+ environments. The activity of KtrAB is regulated by nucleotides and Na+. Previous studies proposed a putative gating mechanism of KtrB regulated by KtrA upon binding to ATP or ADP. However, how Na+ activates KtrAB and the Na+ binding site remain unknown. Here we present the cryo-EM structures of ATP- and ADP-bound KtrAB from Bacillus subtilis (BsKtrAB) both solved at 2.8 Å. A cryo-EM density at the intra-dimer interface of ATP-KtrA was identified as Na+, as supported by X-ray crystallography and ICP-MS. Thermostability assays and functional studies demonstrated that Na+ binding stabilizes the ATP-bound BsKtrAB complex and enhances its K+ flux activity. Comparing ATP- and ADP-BsKtrAB structures suggests that BsKtrB Arg417 and Phe91 serve as a channel gate. The synergism of ATP and Na+ in activating BsKtrAB is likely applicable to Na+-activated K+ channels in central nervous system.

A simplified pneumonia severity index (PSI) for clinical outcome prediction in COVID-19.

BACKGROUND: The Pneumonia Score Index (PSI) was developed to estimate the risk of dying within 30 days of presentation for community-acquired pneumonia patients and is a strong predictor of 30-day mortality after COVID-19. However, three of its required 20 variables (skilled nursing home, altered mental status and pleural effusion) are not discreetly available in the electronic medical record (EMR), resulting in manual chart review for these 3 factors. The goal of this study is to compare a simplified 17-factor version (PSI-17) to the original (denoted PSI-20) in terms of prediction of 30-day mortality in COVID-19. METHODS: In this retrospective cohort study, the hospitalized patients with confirmed SARS-CoV-2 infection between 2/28/20-5/28/20 were identified to compare the predictive performance between PSI-17 and PSI-20. Correlation was assessed between PSI-17 and PSI-20, and logistic regressions were performed for 30-day mortality. The predictive abilities were compared by discrimination, calibration, and overall performance. RESULTS: Based on 1,138 COVID-19 patients, the correlation between PSI-17 and PSI-20 was 0.95. Univariate logistic regression showed that PSI-17 had performance similar to PSI-20, based on AUC, ICI and Brier Score. After adjusting for confounding variables by multivariable logistic regression, PSI-17 and PSI-20 had AUCs (95% CI) of 0.85 (0.83-0.88) and 0.86 (0.84-0.89), respectively, indicating no significant difference in AUC at significance level of 0.05. CONCLUSION: PSI-17 and PSI-20 are equally effective predictors of 30-day mortality in terms of several performance metrics. PSI-17 can be obtained without the manual chart review, which allows for automated risk calculations within an EMR. PSI-17 can be easily obtained and may be a comparable alternative to PSI-20.

Corrigendum: A promoter toolbox for tissue-specific expression supporting translational research in cassava (Manihot esculenta).

[This corrects the article DOI: 10.3389/fpls.2022.1042379.].

Infodemiology of Influenza-like Illness: Utilizing Google Trends' Big Data for Epidemic Surveillance.

Background: Influenza-like illness (ILI) encompasses symptoms similar to influenza, affecting population health. Surveillance, including Google Trends (GT), offers insights into epidemic patterns. Methods: This study used multiple regression models to analyze the correlation between ILI incidents, GT keyword searches, and climate variables during influenza outbreaks. It compared the predictive capabilities of time-series and deep learning models against ILI emergency incidents. Results: The GT searches for "fever" and "cough" were significantly associated with ILI cases (p < 0.05). Temperature had a more substantial impact on ILI incidence than humidity. Among the tested models, ARIMA provided the best predictive power. Conclusions: GT and climate data can forecast ILI trends, aiding governmental decision making. Temperature is a crucial predictor, and ARIMA models excel in forecasting ILI incidences.

Associations of Matrix Metalloproteinase-8 Genotypes to Renal Cell Carcinoma in Taiwan.

BACKGROUND/AIM: Renal cell carcinoma (RCC) presents a formidable clinical challenge due to its aggressive behavior and limited therapeutic options. Matrix metalloproteinase-8 (MMP-8) has recently emerged as a potential biomarker and therapeutic target for various cancers. However, the genetic involvement of MMP-8 in RCC has remained largely obscure. This study aimed to elucidate the role of MMP-8 genotypes in RCC susceptibility. MATERIALS AND METHODS: The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was employed to scrutinize the genotypes of MMP-8 C-799T (rs11225395), Val436Ala (rs34009635), and Lys460Thr (rs35866072) among 118 RCC patients and 590 controls. Furthermore, potential associations between MMP-8 genotypes and age, sex, smoking, alcohol consumption, hypertension, diabetes, and family history status in relation to RCC risk were assessed. RESULTS: No significant disparities in the distribution of MMP-8 rs11225395, rs34009635, and rs35866072 genotypes were observed between the RCC case and control cohorts (p>0.05). Individuals with CT and TT genotypes at MMP-8 rs11225395 exhibited 0.86- and 0.80-fold RCC risks, respectively (OR=0.57-1.31 and 0.42-1.55, p=0.5585 and 0.6228, respectively). Intriguingly, hypertensive individuals carrying the MMP-8 rs11225395 CT or TT genotype demonstrated an elevated risk for RCC compared to those with wild-type CC genotype (p=0.0440). No interactions of MMP-8 genotypes with age, sex, smoking, alcohol consumption, or diabetes status were evident (all p>0.05). No significant association was discerned for MMP-8 rs34009635 or rs35866072 genotypes. CONCLUSION: MMP-8 genotypes appear to have a modest influence on individual susceptibility to RCC. Hypertensive patients with the CT or TT MMP-8 rs11225395 genotype may have an elevated risk of RCC.

Substrate Specificities of Variants of Barley (1,3)- and (1,3;1,4)-ß-d-Glucanases Resulting from Mutagenesis and Segment Hybridization.

Barley (1,3;1,4)-ß-d-glucanase is believed to have evolved from an ancestral monocotyledon (1,3)-ß-d-glucanase, enabling the hydrolysis of (1,3;1,4)-ß-d-glucans in the cell walls of leaves and germinating grains. In the present study, we investigated the substrate specificities of variants of the barley enzymes (1,3;1,4)-ß-d-glucan endohydrolase [(1,3;1,4)-ß-d-glucanase] isoenzyme EII (HvEII) and (1,3)-ß-d-glucan endohydrolase [(1,3)-ß-d-glucanase] isoenzyme GII (HvGII) obtained by protein segment hybridization and site-directed mutagenesis. Using protein segment hybridization, we obtained three variants of HvEII in which the substrate specificity was that of a (1,3)-ß-d-glucanase and one variant that hydrolyzed both (1,3)-ß-d-glucans and (1,3;1,4)-ß-d-glucans; the wild-type enzyme hydrolyzed only (1,3;1,4)-ß-d-glucans. Using substitutions of specific amino acid residues, we obtained one variant of HvEII that hydrolyzed both substrates. However, neither protein segment hybridization nor substitutions of specific amino acid residues gave variants of HvGII that could hydrolyze (1,3;1,4)-ß-d-glucans; the wild-type enzyme hydrolyzed only (1,3)-ß-d-glucans. Other HvEII and HvGII variants showed changes in specific activity and their ability to degrade the (1,3;1,4)-ß-d-glucans or (1,3)-ß-d-glucans to larger oligosaccharides. We also used molecular dynamics simulations to identify amino-acid residues or structural regions of wild-type HvEII and HvGII that interact with (1,3;1,4)-ß-d-glucans and (1,3)-ß-d-glucans, respectively, and may be responsible for the substrate specificities of the two enzymes.