Identification and structure-based engineering of a dipeptidase CpPepD from Clostridium perfringens for the synthesis of l-carnosine

l-Carnosine (l-Car), an endogenous dipeptide presents in muscle and brain tissues of various vertebrates, has a wide range of application values. The enzymatic preparation of l-Car is a promising synthetic method because it avoids the protection and deprotection steps. In the present study, a dipeptidase gene (CpPepD) from Clostridium perfringens with high l-Car synthetic activity was cloned and characterized. In an effort to improve the performance of this enzyme, we carried out site saturation mutagenesis using CpPepD as the template. By the o-phthalaldehyde (OPA)-derived high throughput screening method, mutant A171S was obtained with 2.2-fold enhanced synthetic activity. The enzymatic properties of CpPepD and mutant A171S were investigated. Under the optimized conditions, 63.94 mM (14.46 g L-1) or 67.02 mM (15.16 g L-1) l-Car was produced at the substrate concentrations of 6 M β-Ala and 0.2 M l-His using wild-type or mutant A171S enzyme, respectively. Although the mutation enhanced the enzyme activity, the reaction equilibrium was barely affected.

Chemo-Enzymatic Strategy for the Efficient Synthesis of Steroidal Drugs with 10α-Methyl Group and a Side Chain at C17-Position from Biorenewable Phytosterols

Steroidal pharmaceuticals with a 10α-methyl group or without the methyl group at C10-position are important medicines, but their synthesis is quite challenging, due to that the natural steroidal starting materials usually have a 10β-methyl group which is difficult to be inverted to 10α-methyl group. In this study, 3-((1R,3aS,4S,7aR)-1-((S)-1-hydroxypropan-2-yl)-7a-methyl-5-oxooctahydro-1H-inden-4-yl) propanoic acid (HIP-IPA, 2e) was demonstrated as a valuable intermediate for the synthesis of this kind of active pharmaceutical ingredients (APIs) with a side chain at C17-position. Knockout of a β-hydroxyacyl-CoA dehydrogenase gene and introduction of a sterol aldolase gene into the genetically modified strains of Mycobacterium fortuitum (ATCC 6841) resulted in strains N13Δhsd4AΩthl and N33Δhsd4AΩthl, respectively. Both strains transformed phytosterols into 2e. Compound 2e was produced in 62% isolated yield (25 g) using strain N13Δhsd4AΩthl, and further converted to (3S,3aS,9aS,9bS)-3-acetyl-3a,6-dimethyl-1,2,3,3a,4,5,8,9,9a,9b-decahydro-7H-cyclopenta[a]naphthalen-7-one, which is the key intermediate for the synthesis of dydrogesterone. This study not only overcomes a challenging synthetic problem by enabling an efficient synthesis of dydrogesterone-like steroidal APIs from phytosterols, the well-recognized cheap and readily available biobased raw materials, but also provides insights for redesigning the metabolic pathway of phytosterols to produce other new compounds of relevance to the steroidal pharmaceutical industry.

Discovery and directed evolution of C-C bond formation enzymes for the biosynthesis of β-hydroxy-α-amino acids and derivatives

β-Hydroxy-α-amino acids (β-HAAs) have extensive applications in the pharmaceutical, chemical synthesis, and food industries. The development of synthetic methodologies aimed at producing optically pure β-HAAs has been driven by practical applications. Among the various synthetic methods, biocatalytic asymmetric synthesis is considered a sustainable approach due to its capacity to generate two stereogenic centers from simple prochiral precursors in a single step. Therefore, extensive efforts have been made in recent years to search for effective enzymes which enable such biotransformation. This review provides an overview on the discovery and engineering of C-C bond formation enzymes for the biocatalytic synthesis of β-HAAs. We highlight examples where the use of threonine aldolases, threonine transaldolases, serine hydroxymethyltransferases, α-methylserine aldolases, α-methylserine hydroxymethyltransferases, and engineered alanine racemases facilitated the synthesis of β-HAAs. Additionally, we discuss the potential future advancements and persistent obstacles in the enzymatic synthesis of β-HAAs.

3D Printed Ion-Responsive Personalized Transdermal Patch

Microneedle patches are easy-to-use medical devices for transdermal administration. However, the insufficient insertion of microneedles due to the gap between planar patches and contoured skin affects drug delivery. Herein, we formulate a prepolymer for high-fidelity three-dimensional (3D) printed personalized transdermal patches. With the excellent photoinitiation ability of 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine (Tz), a high-fidelity and precise microneedle patch is successfully fabricated. Upon irradiation of the white illuminator, the doped gold nanoparticles (AuNPs) in the patch release heat and promisingly induce sweat production. With the introduction of Na+, the dominant component of sweat, the curvature of the produced transdermal patch is observed due to the ion-induced network rearrangement. The alkanethiol-stabilized AuNP with an end group of a carboxyl group causes controlled drug release behavior. Furthermore, the irradiation-induced photothermal heating of AuNP can facilitate the sustainability of drug release thanks to the substantially increased particle size of AuNP. These findings demonstrate that the developed prepolymer is a promising candidate for the production of transdermal patches fitting the curvature of the body surface.

Efficacy of preventive interventions against ventilator-associated pneumonia in critically ill patients: an umbrella review of meta-analyses

Many meta-analyses have assessed the efficacy of preventive interventions against ventilator-associated pneumonia (VAP) in critically ill patients. However, there has been no comprehensive analysis of the strength and quality of evidence to date. Systematic reviews of randomized and quasi-randomized controlled trials, which evaluated the effect of preventive strategies on the incidence of VAP in critically ill patients receiving mechanical ventilation for at least 48 h, were included in this article. We identified a total of 34 interventions derived from 31 studies. Among these interventions, 19 resulted in a significantly reduced incidence of VAP. Among numerous strategies, only selective decontamination of the digestive tract (SDD) was supported by highly suggestive (Class II) evidence (risk ratio (RR)=0.439, 95% CI: 0.362-0.532). Based on data from the sensitivity analysis, the evidence for the efficacy of non-invasive ventilation in weaning from mechanical ventilation (NIV) was upgraded from weak (Class IV) to highly suggestive (Class II) (RR=0.32, 95% CI: 0.22-0.46). All preventive interventions were not supported by robust evidence for reducing mortality. Early mobilization exhibited suggestive (Class III) evidence in shortening both intensive length of stay (LOS) in the intensive care unit (ICU) (mean difference (MD)=-0.85, 95% CI: -1.21 to -0.49) and duration of mechanical ventilation (MD=-1.02, 95% CI: -1.41 to -0.63). In conclusion, SDD and NIV are supported by robust evidence for prevention against VAP, while early mobilization has been shown to significantly shorten the LOS in the ICU and the duration of mechanical ventilation. These three strategies are recommendable for inclusion in the ventilator bundle to lower the risk of VAP and improve the prognosis of critically ill patients.

Association of serum lipids and abnormal lipid score with cancer risk: a population-based prospective study

BACKGROUND

Serum lipid levels are associated with cancer risk. However, there still have uncertainties about the single and combined effects of low lipid levels on cancer risk.

METHODS

A prospective cohort study of 33,773 adults in Shanghai between 2016 and 2017 was conducted. Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels were measured. Cox proportional hazard models were used to assess the association of single and combined lipids with overall, lung, colon, rectal, thyroid gland, stomach, and female breast cancers. The effect of the combination of abnormal lipid score and lifestyle on cancer was also estimated.

RESULTS

A total of 926 incident cancer cases were identified. In the RCS analysis, hazard ratios (HRs) of overall cancer for individuals with TC < 5.18 mmol/L or with LDL-C < 3.40 mmol/L were higher. Low TC was associated with higher colorectal cancer risk (HR [95% CI] = 1.76 [1.09-2.84]) and low HDL-C increased thyroid cancer risk by 90%. Abnormal lipid score was linearly and positively associated with cancer risk, and smokers with high abnormal lipid scores had a higher cancer risk, compared to non-smokers with low abnormal lipid scores (P < 0.05).

CONCLUSIONS

Low TC levels were associated with an increased risk of overall and colorectal cancer. More attention should be paid to participants with high abnormal lipid scores and unhealthy lifestyles who may have a higher risk of developing cancer. Determining the specific and comprehensive lipid combinations that affect tumorigenesis remains a valuable challenge.

[The association between body mass index and in-hospital major adverse cardiovascular and cerebral events in patients with acute coronary syndrome]

Objective: To assess the association between body mass index (BMI) and major adverse cardiovascular and cerebrovascular events (MACCE) among patients with acute coronary syndrome (ACS). Methods: This was a multicenter prospective cohort study, which was based on the Improving Care for Cardiovascular Disease in China (CCC) project. The hospitalized patients with ACS aged between 18 and 80 years, registered in CCC project from November 1, 2014 to December 31, 2019 were included. The included patients were categorized into four groups based on their BMI at the time of admission: underweight (BMI<18.5 kg/m2), normal weight (BMI between 18.5 and 24.9 kg/m2), overweight (BMI between 25.0 and 29.9 kg/m2), and obese (BMI≥30.0 kg/m2). Multivariate logistic regression models was used to analyze the relationship between BMI and the risk of in-hospital MACCE. Results: A total of 71 681 ACS inpatients were included in the study. The age was (63.4±14.7) years, and 26.5% (18 979/71 681) were female. And the incidence of MACCE for the underweight, normal weight, overweight, and obese groups were 14.9% (322/2 154), 9.5% (3 997/41 960), 7.9% (1 908/24 140) and 7.0% (240/3 427), respectively (P<0.001). Multivariate logistic regression analysis showed a higher incidence of MACCE in the underweight group compared to the normal weight group (OR=1.30, 95%CI 1.13-1.49, P<0.001), while the overweight and obese groups exhibited no statistically significant difference in the incidence of MACCE compared to the normal weight group (both P>0.05). Conclusion: ACS patients with BMI below normal have a higher risk of in-hospital MACCE, suggesting that BMI may be an indicator for evaluating short-term prognosis in ACS patients.

[Initial experience of transcatheter edge-to-edge repair guided by only transesophageal echocardiography in the treatment of tricuspid insufficiency]

Objective: To evaluate the feasibility and safety of transcatheter tricuspid valve edge-to-edge repair guided by only transesophageal echocardiography (TEE). Methods: Patients with severe tricuspid regurgitation in Fuwai Yunnan Cardiovascular Hospital who met the inclusion criteria based on clinical and echocardiographic evaluationand underwent transcatheter tricuspid valve edge-to-edge repair between January 2022 and May 2023 were prospectively enrolled. The procedure was performed under general anesthesia with endotracheal intubation and solely guided by TEE. The patients underwent clinical evaluation, electrocardiogram and transthoracic echocardiography one month after the procedure. Results: A total of 22 patients (12 males and 10 females) were included, with an average age of (71.3±6.7) years. All 22 patients successfully underwent the transcatheter tricuspid valve edge-to-edge repair under TEE guidance, with an average of (1.5±0.6) clips implanted. Immediately after procedure, six patients had no or trace regurgitation, 15 patients had mild regurgitation, and one patient had moderate regurgitation. All 22 patients completed 30-day follow-up, with four patients having trace regurgitation, 17 patients having mild regurgitation, and one patient having moderate regurgitation. Echocardiographic measurements revealed that effective regurgitant orifice area, regurgitant volume, vena contracta width, and proximal isovelocity surface area radius significantly decreased after the procedure (all P<0.05). In addition, inferior vena cava width, right atrial volume, tricuspid annular diameter, and right ventricular end-diastolic diameter significantly improved (all P<0.05), but tricuspid annular plane systolic excursion and right ventricular fractional area change did not show significant differences compared with those before the procedure (both P>0.05). Conclusion: It has been preliminarily confirmed that transcatheter tricuspid valve edge-to-edge repair solely guided by TEE is feasible and safe, but requires more large-scale studies for further validation.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Metformin ameliorates valve interstitial cell calcification by promoting autophagic flux

Calcific aortic valve disease (CAVD) is the most common heart disease of the developed world. It has previously been established that metformin administration reduces arterial calcification via autophagy; however, whether metformin directly regulates CAVD has yet to be elucidated. In the present study we investigated whether metformin alleviates valvular calcification through the autophagy-mediated recycling of Runx2. Calcification was reduced in rat valve interstitial cells (RVICs) by metformin treatment (0.5-1.5 mM) (P < 0.01), with a marked decrease in Runx2 protein expression compared to control cells (P < 0.05). Additionally, upregulated expression of Atg3 and Atg7 (key proteins required for autophagosome formation), was observed following metformin treatment (1 mM). Blocking autophagic flux using Bafilomycin-A1 revealed colocalisation of Runx2 with LC3 puncta in metformin treated RVICs (P < 0.001). Comparable Runx2 accumulation was seen in LC3 positive autolysosomes present within cells that had been treated with both metformin and hydroxychloroquine in combination (P < 0.001). Mechanistic studies employing three-way co-immunoprecipitation with Runx2, p62 and LC3 suggested that Runx2 binds to LC3-II upon metformin treatment in VICs. Together these studies suggest that the utilisation of metformin may represent a novel strategy for the treatment of CAVD.

Reshaping the Substrate Binding Pocket of β-Amino Acid Dehydrogenase for the Synthesis of Aromatic β-Amino Acids

By reshaping the substrate-binding pocket of β-amino acid dehydrogenase (β-AADH), some variants were obtained with up to 2560-fold enhanced activity toward the model substrates (S)-β-homophenylalanine and (R)-β-phenylalanine. A few aromatic β-amino acids were prepared with >99% ee and high isolated yields via either kinetic resolution of racemates or reductive amination of the corresponding β-keto acids. This work expands the catalytic capability of β-AADHs and highlights their practical application in the synthesis of pharmaceutically relevant β-amino acids.

Photoredox/Enzymatic Catalysis Enabling Redox-Neutral Decarboxylative Asymmetric C-C Coupling for Asymmetric Synthesis of Chiral 1,2-Amino Alcohols

Photocatalysis offers tremendous opportunities for enzymes to access new functions. Herein, we described a redox-neutral photocatalysis/enzymatic catalysis system for the asymmetric synthesis of chiral 1,2-amino alcohols via decarboxylative radical C-C coupling of N-arylglycines and aldehydes by combining an organic photocatalyst, eosin Y, and carbonyl reductase RasADH. Notably, this protocol avoids using any sacrificial reductants. A possible reaction mechanism proposed is that the transformation proceeds through sequential photoinduced decarboxylative radical addition to an aldehyde and a photoenzymatic deracemization pathway. This redox-neutral photoredox/enzymatic strategy is promising not only for effective synthesis of a series of chiral amino alcohols in a green and sustainable manner but also for the design of other novel C-C radical coupling transformations for the synthesis of bioactive molecules.

The radiomic biomarker in non-small cell lung cancer: 18F-FDG PET/CT characterisation of programmed death-ligand 1 status

AIM

To present an integrated 2-[18F]-fluoro-2-deoxy-d-glucose (18F-FDG) positron-emission tomography (PET)/computed tomography (CT) radiomic characterisation of programmed death-ligand 1 (PD-L1) status in non-small-cell lung cancer (NSCLC).

MATERIALS AND METHODS

In this retrospective study, 18F-FDG PET/CT images and clinical data of 394 eligible patients were divided into training (n=275) and test sets (n=119). Next, the corresponding nodule of interest was segmented manually on the axial CT images by radiologists. After which, the spatial position matching method was used to match the image positions of CT and PET, and radiomic features of the CT and PET images were extracted. Radiomic models were built using five different machine-learning classifiers and the performance of the radiomic models were further evaluated. Finally, a radiomic signature was established to predict the PD-L1 status in patients with NSCLC using the features in the best performing radiomic model.

RESULTS

The radiomic model based on the PET intranodular region determined using the logistic regression classifier preformed best, yielding an area under the receiver operating characteristics curve (AUC) of 0.813 (95% CI: 0.812, 0.821) on the test set. The clinical features did not improve the test set AUC (0.806, 95% CI: 0.801, 0.810). The final radiomic signature for PD-L1 status was consisted of three PET radiomic features.

CONCLUSION

This study showed that an 18F-FDG PET/CT-based radiomic signature could be used as a non-invasive biomarker to discriminate PD-L1-positive from PD-L1-negative in patients with NSCLC.

[Comparison on the efficacy of Chinese-made novel-designed mechanical-locked and elastic self-locked transcatheter edge-to-edge repair system in the treatment of patients with functional mitral regurgitation]

Objective: To evaluate and compare the short-term efficacy of domestic mechanical-locked (Clip2Edge) and elastic self-locked (ValveClip) transcranial mitral valve edge-to-edge interventional repair (TEER) devices in the treatment of functional mitral regurgitant valves. Methods: In this retrospective non-randomized comparative study, patients underwent TEER procedure in Fuwai Yunnan Cardiovascular Disease Hospital from May 2022 to April 2023 for heart failure combined with moderate to severe or severe functional mitral valve were divided into Clip2Edge and ValveClip groups based on the TEER system used. Baseline, perioperative, and postoperative 30 d follow-up data were collected and compared between the two groups. The primary outcome was the success rate on the 30 d post operation, while secondary outcomes included immediate postoperative technical success rate and the incidence of all-cause mortality on the 30 d post operation, readmission rate of acute heart failure, cerebral infarction, severe bleeding, and other serious adverse events rates. Results: A total of 60 patients were enrolled, 34 patients were in the Clip2Edge group and 26 in the ValveClip group, mean age was (63.8±9.3) years, and 24 patients (40%) were female. There were no significant differences in baseline data of age, cardiac function, comorbidities, mitral regurgitation 4+(19(73%) vs. 29(85%)), the end-diastolic volume of left ventricle ((220.8±91.2) ml vs. (210.8±71.7) ml) between the two groups (all P>0.05). The technical success rate immediately after the procedure was 100%. There were no readmission of acute heart failure, death, cerebral infarction, severe bleeding, and other serious adverse events up to the 30 d follow-up. Device success rate was similar between the ValveClip group (24 cases (100%)) and the Clip2Edge group (27 cases (96%)) (P>0.05). Conclusion: Both types of novel domestic TEER devices are safe and feasible in treating patients with functional mitral regurgitation.

Semirational Engineering of a Thermostable Carbonyl Reductase for the Precision Synthesis of (2R,3R)-2-Methyl-2-benzyl-3-hydroxycyclopentanone and Its Analogues

2,2-Disubstituted-3-hydroxycyclopentanones are important chiral intermediates for natural products and pharmaceuticals. Through semirational engineering of a thermostable carbonyl reductase CBCR from Cupriavidus sp. BIS7, a mutant L91C/F93I was obtained. Mutant L91C/F93I showed 4- to 36-fold enhanced activities toward 2-methyl-2-benzyl-1,3-cyclopentanedione and its analogues, affording the (2R,3R)-stereoisomers with >99% ee and >99% de. Enzyme-substrate docking studies were performed to reveal the molecular basis for the activity and stereoselectivity improvements.

[The target value of anticoagulation intensity for Chinese patients after mechanical heart valve replacement]

Objective: To explore the optimal intensity of anticoagulation therapy for Chinese patients after mechanical heart valve replacement. Methods: This is a prospective, multicenter, cohort study. The anticoagulation data from in-hospital patients of 35 medical centers and patients in outpatient clinic of 11 medical centers from Anticoagulation Therapy Database of Chinese Patients after Heart Valve Replacement between January 2011 and December 2015 were analyzed. The anticoagulation-relevant complications among different coagulation intensities were compared, and the optimal value of anticoagulation intensity for Chinese patients after mechanical heart valve replacement were analyzed. Results: A total of 24 433 patients were in the final analysis, including 13 634 females and 10 799 males, with a median age of 49.0 (3-80) years. International normalized ratio (INR) values of in-hospital patients were recorded 94 286 times, with the mean value of 1.8±0.7, and 87.6% (82 595/94 286) of them were within the range of 1.5 to 2.5. During a median follow-up time of 19.2 (1.0-58.8) months, a total of 17 331 outpatient clinic patients were followed up, with the follow-up rate of 89.1% (17 331/19 452) and a total of 27 803 patient-years (Pty), including 4 038 aortic valve replacement (AVR), 8 215 mitral valve replacement (MVR), 4 437 AVR plus MVR (double valve replacement, DVR) replacement and 641 tricuspidvalve replacement (TVR). A total of 101 860 INR measurements were recorded, with the mean value of 1.8±0.5, and 64.8% (66 005/101 860) of them were within the range of 1.5-2.5. The rates of anticoagulation-related complications of the patients with INR of 1.5-2.5 (0.65/100 Pty) were lower than those of other INR value patients (INR<1.5: 1.31/100 Pty, RR=2.01, 95%CI: 1.59-2.51, P<0.001; INR>2.5: 2.34/100 Pty, RR=3.60, 95%CI: 2.84-4.52, P<0.001). The rates of anticoagulation-related complications of AVR and MVR patients without risk factors and with INR of 1.5-2.0 were lower than those of other INR value patients (AVR: 0.15/100 Pty vs 0.38/100 Pty, RR=2.57, 95%CI: 1.02-7.28, P=0.029; MVR: 0.23/100 Pty vs 0.56/100 Pty, RR=2.42, 95%CI: 1.39-4.38, P<0.001), and the rate of anticoagulation-related complications of DVR patients with INR of 2.0-2.5 was lower than those of other INR value patients (0.32/100 Pty vs 0.62/100 Pty, RR=1.94, 95%CI: 1.03-3.79, P=0.029). Conclusions: A target INR range of 1.5-2.5 is recommended for Chinese patients after mechanical heart valve replacement. The optimal INR value for isolated AVR or MVR patients without risk factors was 1.5-2.0, while the optimal INR value for isolated AVR or MVR patients with risk factors and all the TVR or DVR patients was 2.0-2.5.

[BCS1Neonatal growth retardation and lactic acidosis initiated by novel mutation sites in L gene]

This study aims to analyze the clinical characteristics and genetic variations of two cases with developmental delay and lactic acidosis in a family, and to explore the relationship between genetic variations and clinical features. A retrospective analysis was conducted on the clinical characteristics of two siblings with developmental delay and lactic acidosis who were treated at the Neonatal Department of Children's Hospital of Chongqing Medical University in May 2019 and December 2021, respectively. Whole-exome sequencing was used to detect genetic variations in the affected children. Homology modeling of the BCS1L protein was performed to analyze the structural and functional changes of the protein. The correlation between genetic variations and clinical phenotypes was analyzed. The results showed that the main clinical features of the two affected children in this family were manifestations of mitochondrial respiratory chain complex Ⅲ deficiency, including prematurity, developmental delay, respiratory failure, lactic acidosis, cholestasis, liver dysfunction, renal tubular lesions, coagulation dysfunction, anemia, hypoglycemia, hypotonia, and early death. Whole-exome sequencing revealed a novel deletion mutation c.486_488delGGA (p.E163del) and a novel missense mutation c.992C>T (p.T331I) in the BCS1L gene. Structural analysis of the homology modeling showed that the compound heterozygous mutation had a significant impact on protein function. In conclusion, the novel mutation site c.992C>T (p.T331I) in the BCS1L gene is a "likely pathogenic" mutation, and the compound heterozygous mutation is closely related to the phenotype of mitochondrial respiratory chain complex Ⅲ deficiency.

Intravenous N-acetylcysteine in respiratory disease with abnormal mucus secretion

OBJECTIVE

Evidence for the mucolytic and expectorant efficacy of intravenous (IV) N-acetylcysteine (NAC) is limited. This study aimed to evaluate in a large, multicenter, randomized, controlled, subject, and rater-blinded study whether IV NAC is superior to placebo and non-inferior to ambroxol in improving sputum viscosity and expectoration difficulty.

PATIENTS AND METHODS

A total of 333 hospitalized subjects from 28 centers in China with respiratory disease (such as acute bronchitis, chronic bronchitis and exacerbations, emphysema, mucoviscidosis, and bronchiectasis) and abnormal mucus secretion were randomly allocated in a 1:1:1 ratio to receive NAC 600 mg, ambroxol hydrochloride 30 mg, or placebo as an IV infusion twice daily for 7 days. Mucolytic and expectorant efficacy was assessed by ordinal categorical 4-point scales and analyzed by stratified and modified Mann-Whitney U statistics.

RESULTS

NAC showed consistent and statistically significant superiority to placebo and non-inferiority to ambroxol in change from baseline to day 7 in both sputum viscosity scores [mean (SD) difference 0.24 (0.763), p<0.001 vs. placebo] and expectoration difficulty score [mean (SD) difference 0.29 (0.783), p=0.002 vs. placebo]. Safety findings confirm the good tolerability profile of IV NAC reported from previous small studies, and no new safety concerns were identified.

CONCLUSIONS

This is the first large, robust study of the efficacy of IV NAC in respiratory diseases with abnormal mucus secretion. It provides new evidence for IV NAC administration in this indication in clinical situations where the IV route is preferred.

Enantiodivergent Synthesis of 1-Heteroaryl Tetrahydroisoquinolines Catalyzed by Imine Reductases

Two enantiocomplementary imine reductases (IREDs) with high enantioselectivity were identified with catalytic activity toward the reduction of 1-heteroaryl dihydroisoquinolines through a screening of wild-type IREDs and enzyme engineering. Furthermore, (R)-IR141-L172M/Y267F and (S)-IR40 were applied to access a series of different 1-heteroaryl tetrahydroisoquinolines with high to excellent ee values (82 to >99%) and isolated yields (80 to 94%), thereby providing an effective method to construct this class of pharmaceutically important alkaloids, such as the intermediate of kinase inhibitor TAK-981.

Predictors of postoperative biochemical remission in lower Knosp grade growth hormone-secreting pituitary adenomas: a large single center study

PURPOSE

Growth hormone-secreting pituitary adenomas (GH-PAs) with a low Knosp grade are typically associated with a good postoperative biochemical remission (BR) rate. However, a proportion of patients do not achieve remission. In this study, we aimed to investigate predictive factors of postoperative remission for lower Knosp GH-PAs.

METHODS

In this retrospective study, we enrolled 140 patients who were diagnosed with lower Knosp (0-2) GH-PAs and received trans-sphenoidal surgery between December 2016 and June 2021 from the largest pituitary tumor surgery center in southern China. The univariate, binary Logistic regression, and receiver operating characteristic curve (ROC) analyses were employed to determine independent predictors and cutoff values of remission. The postoperative outcome was defined as remission using the 2010 consensus criteria of acromegaly.

RESULTS

One hundred and thirty six patients (97.1%) achieved gross total resection. The postoperative long-term BR was 68.6%. Empty sella, tumor maximum diameter and postoperative GH levels were independent factors predicting remission. ROC revealed that postoperative 24 h GH ≤ 1.3 ng/mL and  ≤ 1.23 ng/mL were valuable predictors for 3-month and long-term remission respectively, and that postoperative 3-month GH ≤ 1.6 ng/mL and tumor maximum diameter  ≤ 17 mm were predictors for delayed remission.

CONCLUSION

Early postoperative GH levels can be used as predictors of remission. However, BR was not associated with preoperative somatostatin analogs therapy or Knosp grade (0-2). For patients without residual tumor or recurrence and whose GH levels are slightly elevated within 1 year after surgery, adjuvant treatments may not be necessary.

CircOMA1 modulates cabergoline resistance by downregulating ferroptosis in prolactinoma

PURPOSE

Prolactinomas are one of the most common pituitary neuroendocrine tumors (PitNETs), accounting for approximately 50% of all pituitary tumors. Dopamine agonists are the main treatment for prolactinoma, but a small number of patients are still resistant to pharmacotherapy. Recent discoveries have revealed that ferroptosis is involved in regulating tumor drug resistance. However, the role of ferroptosis in prolactinoma has not been reported. In this study, we aimed to explore the mechanism of a circRNA in ferroptosis in prolactinoma.

METHODS

The expression of circOMA1 in prolactinoma tissues was examined by quantitative reverse transcription PCR (qRT-PCR). The biological function of circOMA1 was evaluated in vitro and in vivo. To explore the role of ferroptosis in prolactinoma, we used qRT-PCR and western blotting. Glutamate-cysteine ligase, modifier subunit (GCLM) was predicted to be a direct target gene of miR-145-5p by bioinformatics analysis, which was confirmed by luciferase reporter assays.

RESULTS

circOMA1 was overexpressed in drug-resistant prolactinoma tissues compared with sensitive prolactinoma samples. We further found that circOMA1 promoted MMQ cells growth in vivo and in vitro. In addition, GCLM was directly targeted by miR-145-5p and indirectly regulated by circOMA1. Importantly, circOMA1 induced ferroptosis resistance through the increased expression of Nrf2, GPX4, and xCT, and circOMA1 attenuated CAB-induced ferroptosis in MMQ cells in vivo and in vitro.

CONCLUSION

The present study demonstrates that circOMA1 attenuates CAB efficacy through ferroptosis resistance and may be a new therapeutic target for the individualized treatment of DA-resistant prolactinoma patients.

Understanding Online Registry Facilitators and Barriers Experienced by Black Brain Health Registry Participants: The Community Engaged Digital Alzheimer's Research (CEDAR) Study

BACKGROUND

Failure of Alzheimer's disease and related diseases (ADRD) research studies to include and engage Black participants is a major issue, which limits the impact and generalizability of research findings. Little is known about participation of Black adults in online ADRD-related research registries.

OBJECTIVES

As part of the Community Engaged Digital Alzheimer's Research (CEDAR) Study, this study aims to increase our understanding of facilitators and barriers of Black adults to participating in ADRD-related online registries, as well as to understand their preferences for communication channels.

DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS

We invited all Black participants enrolled in the Brain Health Registry (BHR) to complete a cross-sectional online survey. The survey consisted of rating scales and open-text questions asking about their attitudes towards brain health research, reasons for joining and continuing to participate in BHR, difficulties with participating, and preferences for modes of contact and website usage.

RESULTS

Of all invited Black BHR participants (N=3,636), 198 (5.5%) completed the survey. The mean age was 58.4 (SD=11.3), mean years of education were 16.3 (SD=2.4), and 85.5% identified as female. Reported facilitators for joining and continuing to participate in BHR were personal interest (e.g., learning more about own brain health) and altruism (e.g., helping research). Among additional registry features which could encourage return, receiving feedback or scores about BHR tasks was rated the highest. Of those who found BHR participation difficult (21%), the most frequent reason was time burden. The most preferred way of receiving study information was via email. Participants reported that the websites that they used the most were YouTube and Facebook.

DISCUSSION

The results of our study can inform the development of culturally-responsive registry features and engagement efforts to improve inclusion and participation of Black adults in online ADRD research. Providing participants with feedback about their registry performance and reducing the number of registry tasks are among the recommended strategies.

The Community Engaged Digital Alzheimer's Research (CEDAR) Study: A Digital Intervention to Increase Research Participation of Black American Participants in the Brain Health Registry

BACKGROUND

Although Black/African American older adults bear significant inequities in prevalence, incidence, and outcomes of Alzheimer's disease and related dementias, they are profoundly under-included in Alzheimer's Disease research. Community-Engaged Research (e.g., equitable community/science partnerships) is an evidence-based approach for improving engagement of underrepresented populations into Alzheimer's Disease research, but has lacked scalability to the national level. As internet use among older adults from underrepresented populations continues to grow, internet-based research shows promise as a feasible, valid approach to engagement and longitudinal assessment. The Community Engaged Digital Alzheimer's Research (CEDAR) study utilizes a community-engaged research approach to increase the engagement and research participation of Black/African American adults in the Brain Health Registry (BHR) and Alzheimer Disease clinical research.

OBJECTIVES

To describe the methods and evaluate the feasibility of the CEDAR culturally-informed digital platform within BHR.

DESIGN

All Black/African American participants in BHR were invited to enroll in CEDAR and to consider serving on a newly convened Community-Scientific Partnership Board to guide the study. The community board guided the development a culturally-informed cadre of engagement materials and strategies to increase research participation. Engagement strategies included incentives for study task completion, culturally-informed communications (e.g., landing page, emails and social media), resources about brain health, and video and written testimonials by CEDAR participants.

SETTING

BHR, an Internet-based registry and cohort.

PARTICIPANTS

BHR participants self-identifying as Black/African American were invited to enroll. All participants who signed an online informed consent document were enrolled.

MEASUREMENTS

We report the number of participants invited, enrolled, completed tasks, and volunteered to join the community board. We compared the demographics, cognitive profile, and baseline BHR task completion rates between CEDAR participants and all those invited to join the study.

RESULTS

Of 3738 invited, 349 (9.34%) enrolled in CEDAR. 134 (37% of CEDAR participants) volunteered to join the community board, of which 19 were selected for the community board. Compared to those invited, the CEDAR cohort had a higher percentage of female participants (84.5%) and a lower percentage of participants who identify as belonging to more than one ethnocultural group (21.8%). Compared to those did not enroll in CEDAR, those enrolled in CEDAR had a higher percentage of participants completing all BHR tasks (22%) and a higher percentage of participants completing at least one cognitive test (76%). Those enrolled in CEDAR also had a higher percentage of participants having an enrolled study partner (18%).

CONCLUSIONS

A culturally-informed Community-Engaged Research approach, including a remotely-convened community board, to engagement of Black/African American participants in an online research registry is feasible. This approach can be adapted for use in various clinical studies and other settings. Future studies will evaluate the effectiveness of the engagement strategies.

[Effect of "one-stop" outpatient management on the control rate of multiple metabolic disorders patients]

Objective: To explore the effect of "one-stop" outpatient management on the therapeutic schedule and control rate of patients with metabolic disorders. Methods: A total of 332 patients who met the inclusion criteria were enrolled and treated regularly in the "one-stop" outpatient department of the Department of Cardiology of the Third Hospital of Peking University from November 1, 2020 to April 30, 2022. The general information, personal history, family history, drug treatment plan, blood pressure, height, weight, waist circumference, and hip circumference of patients were collected through the outpatient electronic medical record system, and patients were followed up through conducting "one-stop" comprehensive management. The baseline clinical characteristics were analyzed, and the changes of metabolic indexes, treatment conditions and control rate of patients with different metabolic disorders before and after the "one-stop" outpatient management were compared. Results: The time interval between the first visit and the last visit was 44 (26, 60) weeks in 332 patients, whose age was (57.2±13.2) years, including 219 males (66.0%). After the "one-stop" outpatient management, fasting blood glucose (FBG) [ 6.6 (5.6, 7.9) mmol/L vs 6.3 (5.6, 6.9) mmol/L], glycosylated hemoglobin A1c (HbA1c) [ (7.2±1.5) % vs (6.6±0.8) %], low density lipoprotein cholesterol (LDL-C) [ 2.70 (1.97, 3.55) mmol/L vs 2.04 (1.66, 2.63) mmol/L] and blood uric acid (UA) [ (383.7±107.1) μmol/L vs (341.2±90.6) μmol/L] all decreased significantly (all P values<0.05). The control rates of hypertension (19.8% vs 28.2%), diabetes (45.2% vs 66.5%), hyperlipidemia (54.9% vs 87.6%) and hyperuricemia (16.7% vs 49.0%) were significantly improved after the "one-stop" outpatient management (all P values<0.05). Conclusion: The "one-stop" outpatient management of cardiovascular department can significantly improve the metabolic condition and the control rate of patients with multiple metabolic disorders.

[Diagnostic value and application of 24 h multichannel intraluminal impedance-pH monitoring in children with gastroesophageal reflux disease]

Objective: To evaluate the diagnostic value and application of 24 h multichannel intraluminal impedance-pH (24 h MII-pH) monitoring in children with gastroesophageal reflux disease (GERD). Methods: This is a cross-sectional study. From January 2013 to December, 2020, 417 patients who received 24 h MII-pH monitoring in Department of Gastroenterology of Children's Hospital Capital Institute of Pediatrics were included. According to results, these children were divided into the GERD and non-GERD groups. Furthermore, the 132 children with GERD who had gastroscopy were divided into the reflux esophagitis (RE) and non-erosive reflux disease (NE) groups to investigate the differences in their refluxes. Non-parametric Mann-Whitney U test or indepentent sample t test was used for comparisons between the groups. Results: Among the 417 children, 232 were males and 185 females, aged (7.3±3.9) years. The course of disease was 0.5 (0.1, 2.0) years. The main clinical symptoms included acid reflux (128 cases), vomiting (173 cases), abdominal pain (101 cases), and cough (76 cases). The 24 h MII-pH monitoring were positive in 243 children (58.3%, 243/417), which was higher than that by 24 h esophageal pH monitoring (43.6%, 182/417). The 24 h MII-pH monitoring results demonstrated significant differences in the episodes of acid reflux, weakly acidic reflux, non-acidic reflux, liquid reflux and mixed reflux between GERD and non-GERD groups (10 (4, 19) vs. 4 (1, 9) times/24 h, 14 (6, 32) vs. 7 (3, 13) times/24 h, 0 (0, 0) vs. 0 (0, 0) times/24 h, 19 (10, 34) vs. 8 (3, 14) times/24 h, and 6 (2, 12) vs. 3 (1, 5) times/24 h, Z=-6.96, -7.25, -5.62, -8.75, and -6.48, all P<0.05, respectively). Besides, the results also showed significant differences in Boix-Ochoa score, episodes of long reflux, course of long reflux, and episodes of weakly acidic reflux between the RE and NE groups (51.2 (21.4, 153.2) vs. 20.7 (12.1, 34.7), 5 (2, 10) vs. 1 (0, 4) times/24 h, 19 (7, 87) vs. 8 (3, 22) min, and 5 (2, 15) vs. 15 (6, 33) times/24 h, Z=-3.44, -3.41, -2.65, and -2.27, all P<0.05, respectively). Conclusion: 24 h MII-pH monitoring not only improves the detection rate of GERD in children, but also provides a possibility to early etiological diagnosis.

[Green biosynthesis of chiral pharmaceutical chemicals]

In nature, chirality is a common phenomenon and closely related to life, also significantly influences the properties of the substance. The chemical synthesis of chiral pharmaceutical chemicals has encountered challenges such as poor atom economy and process economy, serious environmental pollution and waste of the resource. The biosynthesis route has the advantages of high selectivity and environmental-friendliness. In recent years, the rapid developments in the accessible key enzymes, understanding of catalytic mechanism, construction of new synthetic pathways of optical pure intermediates, process development and scale-up production have made it possible to address the challenges encountered in the production of active pharmaceutical ingredients, thus promoting a green and sustainable pharmaceutical industry in China. This review summarized the achievements made in this field by researchers at Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences.

[Construction of strains for bioconversion of steroid key intermediates and intelligent industrial production]

Steroidal hormone pharmaceuticals are the second largest class of medicines after antibiotics. At present, the initial materials of the steroidal industry have shifted from sapogenins, which were extracted from plants of the genus Dioscore to phytosterols. As a byproduct of soybean oil production, phytosterols are readily available and of low prices. Androstenedione (AD), androstadiendione (ADD), 9α-hydroxy-androstenedione (9α-OH-AD) and a series of key intermediates used in the synthesis of steroidal pharmaceuticals can be produced from phytosterols by microbial transformation. Nevertheless, due to the long metabolic pathways, the byproducts and the complex regulation, traditional microbial screening, mutagenizing methods and the oil-water biphasic transformation systems are no longer suitable for current industrial production. A new generation strains for the production of key steroidal pharmaceutical intermediates have been constructed and an intelligent production process has been jointly developed by us and Zhejiang Xianju Junye Pharmaceutical Co. Ltd.. Taking these products and processes as an example, this article reviews the improvement of strains for the production of steroidal pharmaceutical intermediates and the development of biotransformation process on an industrial scale. With the development of synthetic biology, it is expected to develop a new generation of intermediates which are more suitable for the synthesis of steroidal medicines. Moreover, de novo biosynthesis the steroidal active pharmaceutical ingredients from glucose is also expected. The application of these new-generation strains constructed by biotechnology (BT) in modern factories based on informatization and intelligent technology (IT) will be more efficient and greener, and create remarkable social and economic values.

[Influence of Helicobacter pylori infection and its eradication treatment on small intestinal bacterial overgrowth]

Objectives: To analyze the effects of Helicobacter pylori (H. pylori) infection and eradication therapy on small intestinal bacterial overgrowth (SIBO). Methods: From September to December 2021, patients with abdominal symptoms who received ¹³C urea breath test at the Department of Gastroenterology in Peking University First Hospital were enrolled.¹³C urea breath test was used to detect H. pylori infection and patients were divided into H. pylori positive and negative groups accordingly. Lactulose hydrogen methane breath test was performed to determine SIBO. H. pylori positive patients were treated with quadruple therapy including amoxicillin, metronidazole, rabeprazole and bismuth potassium citrate. ¹³C urea breath test and lactulose hydrogen methane breath test were reexamined 6 weeks after the treatment. Results: A total of 102 patients (49 males and 53 females) were enrolled, with a mean age of (42.1±9.9) years. Among them, 49 patients were H. pylori negative and 53 were H. pylori positive. Moreover, 47 patients were SIBO positive and 55 were SIBO negative. There was no significant difference in age, sex, body mass index, abdominal symptoms and the diagnosis of chronic atrophic gastritis between H. pylori positive and negative patients at the enrollment (all P>0.05). The detection rate of SIBO in H. pylori infected patients was higher than that in uninfected patients, and the difference was statistically significant (60.4% vs 30.6%, P=0.003). Patients with SIBO had significantly more frequent abdominal distension (36.2% vs 10.9%, P=0.002) and constipation (27.7% vs 1.8%, P<0.001) than patients without SIBO. The rate of SIBO after H. pylori eradication treatment was significantly lower than that before treatment (20.8% vs 60.4%, P<0.001). The remission rate of SIBO after eradication therapy was 66.7% (20/30). Besides, patients had obvious improvement of constipation (6.0% vs 18.9%, P=0.008), and the incidence of other abdominal symptoms decreased to various degrees including diarrhea, abdominal pain, abdominal distention and poor appetite. Conclusion: H. pylori infection increases the risk of SIBO, and the quadruple regimen containing amoxicillin and metronidazole has a therapeutic effect for patients with H.pylori infection and concomitant SIBO.

Effect of polyethylene Glycol Loxenatide (long-acting GLP-1RA) on lipid, glucose levels and weight in type 2 diabetes mellitus patients with obesity

OBJECTIVE

To explore the effect of polyethylene glycol loxenatide (long-acting GLP-1R agonist) on the lipid, glucose levels, and weight in type 2 diabetes mellitus patients with obesity.

PATIENTS AND METHODS

A total of 40 obese patients with type 2 diabetes mellitus in our hospital from July 2019 to June 2020 were randomly divided into a control group and a study group. The study group was treated with metformin and polyethylene glycol loxenatide injection, while the control group was treated with metformin.

RESULTS

Before treatment, there was no significant difference in FPG (Fasting Blood Glucose) and PPG (Post Prandial Glycaemia) levels between the study group and the control group (p>0.05). After a treatment period, the FPG and PPG levels in the study group were significantly lower than those in the control group (p<0.05). With the longer treatment time, the patient's weight and BMI were lower (p<0.05). The weight and BMI of patients changed the least after one month of treatment, and the weight and BMI changed the most after more than seven months of treatment. After a period of treatment, the levels of FPG and PPG in the blood of male patients in the study group were significantly lower than those of female patients (p<0.05). After treatment, the TG level of the study group was significantly lower than that of the control group (p<0.05). In comparison, the HDL-C level was significantly higher than that of the control group (p<0.05).

CONCLUSIONS

Lipid and glucose levels of type 2 diabetes mellitus patients with obesity have decreased after 12 weeks of polyethylene glycol loxanatide use. The weight of type 2 diabetes mellitus patients with obesity has changed after using polyethylene glycol loxenatide for a period of treatment. Among them, there is a certain relationship between body weight and treatment time, gender, and original body weight, which is worthy of further research and promotion in clinical practice.

Ultrafast Suppression of the Ferroelectric Instability in KTaO_{3}

We use an x-ray free-electron laser to study the lattice dynamics following photoexcitation with ultrafast near-UV light (wavelength 266 nm, 50 fs pulse duration) of the incipient ferroelectric potassium tantalate, KTaO_{3}. By probing the lattice dynamics corresponding to multiple Brillouin zones through the x-ray diffuse scattering with pulses from the Linac Coherent Light Source (LCLS) (wavelength 1.3 Å and <10  fs pulse duration), we observe changes in the diffuse intensity associated with a hardening of the transverse acoustic phonon branches along Γ to X and Γ to M. Using force constants from density functional theory, we fit the quasiequilibrium intensity and obtain the instantaneous lattice temperature and density of photoexcited charge carriers. The density functional theory calculations demonstrate that photoexcitation transfers charge from oxygen 2p derived π-bonding orbitals to Ta 5d derived antibonding orbitals, further suppressing the ferroelectric instability and increasing the stability of the cubic, paraelectric structure.

Asymmetric Synthesis of Fused-Ring Tetrahydroisoquinolines and Tetrahydro-β-carbolines from 2-Arylethylamines via a Chemoenzymatic Approach

While chiral fused-ring tetrahydroisoquinoline (THIQ) and tetrahydro-β-carboline (THβC) scaffolds have attracted considerable interest due to their wide spectrum of biological activities, the synthesis of optically pure chiral fused-ring THIQs and THβCs remains a challenging task. Herein, a group of active imine reductases were identified to convert the imine precursors into the corresponding enantiocomplementary fused-ring THIQs and THβCs with high enantioselectivity and conversion, establishing an efficient and green chemoenzymatic approach to fused-ring alkaloids from 2-arylethylamines.

Biotransformation Enables Innovations Toward Green Synthesis of Steroidal Pharmaceuticals

Steroids have been widely used in birth-control, prevention, and treatment of various diseases, representing the largest sector after antibiotics in the global pharmaceutical market. The steroidal active pharmaceutical ingredients (APIs) have been produced via partial synthetic processes first mainly from sapogenins, which was converted into 16-dehydropregnenolone by the famous "Marker Degradation". Traditional mutation and screening, and process engineering have resulted in the industrial production of 4-androstene-3,17-dione (AD), androst-1,4-diene-3,17-dione (ADD), 9α-hydroxy-androsta-4-ene-3,17-dione (9α-OH-AD), and so on, which serve as the key intermediates for the synthesis of steroidal APIs. Recently, genetic and metabolic engineering have generated highly efficient microbial strains for the production of these precursors, leading to the replacement of sapogenins with phytosterols as the starting materials. Further advances in synthetic biology hold promise in the design and construction of microbial cell factories for the industrial production of steroidal intermediates and/or APIs from simple carbon sources such as glucose. Integration of biotransformation into the synthesis of steroidal APIs can greatly reduce the number of reaction steps, achieve lower waste discharge and higher production efficiency, thus enabling a greener steroidal pharmaceutical industry.

Use of diamond sensors for a high-flux, high-rate X-ray pass-through diagnostic

X-ray free-electron lasers (XFELs) deliver pulses of coherent X-rays on the femtosecond time scale, with potentially high repetition rates. While XFELs provide high peak intensities, both the intensity and the centroid of the beam fluctuate strongly on a pulse-to-pulse basis, motivating high-rate beam diagnostics that operate over a large dynamic range. The fast drift velocity, low X-ray absorption and high radiation tolerance properties of chemical vapour deposition diamonds make these crystals a promising candidate material for developing a fast (multi-GHz) pass-through diagnostic for the next generation of XFELs. A new approach to the design of a diamond sensor signal path is presented, along with associated characterization studies performed in the XPP endstation of the LINAC Coherent Light Source (LCLS) at SLAC. Qualitative charge collection profiles (collected charge versus time) are presented and compared with those from a commercially available detector. Quantitative results on the charge collection efficiency and signal collection times are presented over a range of approximately four orders of magnitude in the generated electron-hole plasma density.

Asymmetric Synthesis of N-Substituted 1,2-Amino Alcohols from Simple Aldehydes and Amines by One-Pot Sequential Enzymatic Hydroxymethylation and Asymmetric Reductive Amination

The chiral N-substituted 1,2-amino alcohol motif is found in many natural and synthetic bioactive compounds. In this study, enzymatic asymmetric reductive amination of α-hydroxymethyl ketones with enantiocomplementary imine reductases (IREDs) enabled the synthesis of chiral N-substituted 1,2-amino alcohols with excellent ee values (91-99 %) in moderate to high yields (41-84 %). Furthermore, a one-pot, two-step enzymatic process involving benzaldehyde lyase-catalyzed hydroxymethylation of aldehydes and subsequent asymmetric reductive amination was developed, offering an environmentally friendly and economical way to produce N-substituted 1,2-amino alcohols from readily available simple aldehydes and amines. This methodology was then applied to rapidly access a key synthetic intermediate of anti-malaria and cytotoxic tetrahydroquinoline alkaloids.

Observation of photo-induced plasmon-phonon coupling in PbTe via ultrafast x-ray scattering

We report the observation of photo-induced plasmon-phonon coupled modes in the group IV-VI semiconductor PbTe using ultrafast x-ray diffuse scattering at the Linac Coherent Light Source. We measure the near-zone-center excited-state dispersion of the heavily screened longitudinal optical (LO) phonon branch as extracted from differential changes in x-ray diffuse scattering intensity following above bandgap photoexcitation. We suggest that upon photoexcitation, the LO phonon-plasmon coupled (LOPC) modes themselves become coupled to longitudinal acoustic modes that drive electron band shifts via acoustic deformation potentials and possibly to low-energy single-particle excitations within the plasma and that these couplings give rise to displacement-correlations that oscillate in time with a period given effectively by the heavily screened LOPC frequency.

A New 3-Ketosteroid-Δ1–Dehydrogenase with High Activity and Broad Substrate Scope for Efficient Transformation of Hydrocortisone at High Substrate Concentration

3-Ketosteroid-Δ¹-dehydrogenases (KstDs [EC 1.3.99.4]) catalyze the Δ¹-dehydrogenation of steroids and are a class of important enzymes for steroid biotransformations. In this study, nine putative kstD genes from different origins were selected and overexpressed in Escherichia coli BL21(DE3). These recombinant enzymes catalyzed the Δ¹-desaturation of a variety of steroidal compounds. Among them, the KstD from Propionibacterium sp. (PrKstD) displayed the highest specific activity and broad substrate spectrum. The detailed catalytic characterization of PrKstD showed that it can convert a wide range of 3-ketosteroid compounds with diverse substituents, ranging from substituents at the C9, C10, C11 and C17 position through substrates without C4-C5 double bond, to previously inactive C6-substituted ones such as 11β,17-dihydroxy-6α-methyl-pregn-4-ene-3,20-dione. Reaction conditions were optimized for the biotransformation of hydrocortisone in terms of pH, temperature, co-solvent and electron acceptor. By using 50 g/L wet resting E. coli cells harboring PrKstD enzyme, the conversion of hydrocortisone was about 92.5% within 6 h at the substrate concentration of 80 g/L, much higher than the previously reported results, demonstrating the application potential of this new KstD.

Directed evolution of an alcohol dehydrogenase for the desymmetric reduction of 2,2-disubstituted cyclopenta-1,3-diones by enzymatic hydrogen transfer

Directed evolution of carbonyl reductase TbADH created mutant Tb2 with balanced activity toward ethyl secodione and isopropanol, enabling the desymmetric reduction of ethyl secodione to give (13R,17S)-ethyl secol with 94% yield, >99% ee and >99% de.

[Catalytic mechanism, molecular engineering and applications of threonine aldolases]

Threonine aldolases catalyze the aldol condensation of aldehydes with glycine to furnish β-hydroxy-α-amino acid with two stereogenic centers in a single reaction. This is one of the most promising green methods for the synthesis of optically pure β-hydroxy-α-amino acid with high atomic economy and less negative environmental impact. Several threonine aldolases from different origins have been identified and characterized. The insufficient -carbon stereoselectivity and the challenges of balancing kinetic versus thermodynamic control to achieve the optimal optical purity and yield hampered the application of threonine aldolases. This review summarizes the recent advances in discovery, catalytic mechanism, high-throughput screening, molecular engineering and applications of threonine aldolases, with the aim to provide some insights for further research in this field.