Novel RNA molecular bioengineering technology efficiently produces functional miRNA agents.

Genome-derived microRNAs (miRNAs or miRs) govern posttranscriptional gene regulation and play important roles in various cellular processes and disease progression. While chemo-engineered miRNA mimics or biosimilars made in vitro are widely available and used, miRNA agents produced in vivo are emerging to closely recapitulate natural miRNA species for research. Our recent work has demonstrated the success of high-yield, in vivo production of recombinant miRNAs by using human tRNA (htRNA) fused precursor miRNA (pre-miR) carriers. In this study, we aim to compare the production of bioengineered RNA (BioRNA) molecules with glycyl versus leucyl htRNA fused hsa-pre-miR-34a carriers, namely, BioRNAGly and BioRNALeu, respectively, and perform the initial functional assessment. We designed, cloned, overexpressed, and purified a total of 48 new BioRNA/miRNAs, and overall expression levels, final yields, and purities were revealed to be comparable between BioRNAGly and BioRNALeu molecules. Meanwhile, the two versions of BioRNA/miRNAs showed similar activities to inhibit non-small cell lung cancer cell viability. Interestingly, functional analyses using model BioRNA/miR-7-5p demonstrated that BioRNAGly/miR-7-5p exhibited greater efficiency to regulate a known target gene expression (EGFR) than BioRNALeu/miR-7-5p, consistent with miR-7-5p levels released in cells. Moreover, BioRNAGly/miR-7-5p showed comparable or slightly greater activities to modulate MRP1 and VDAC1 expression, compared with miRCURY LNA miR-7-5p mimic. Computational modeling illustrated overall comparable 3D structures for exemplary BioRNA/miRNAs with noticeable differences in htRNA species and payload miRNAs. These findings support the utility of hybrid htRNA/hsa-pre-miR-34a as reliable carriers for RNA molecular bioengineering, and the resultant BioRNAs serve as functional biologic RNAs for research and development.

The Growing Class of Novel RNAi Therapeutics.

The clinical use of RNA interference (RNAi) molecular mechanisms has introduced a novel, growing class of RNA therapeutics capable of treating diseases by controlling target gene expression at the posttranscriptional level. With the newly approved nedosiran (Rivfloza), there are now six RNAi-based therapeutics approved by the United States Food and Drug Administration (FDA). Interestingly, five of the six FDA-approved small interfering RNA (siRNA) therapeutics [patisiran (Onpattro), lumasiran (Oxlumo), inclisiran (Leqvio), vutrisiran (Amvuttra), and nedosiran] were revealed to act on the 3'-untranslated regions of target mRNAs, instead of coding sequences, thereby following the common mechanistic action of genome-derived microRNAs (miRNA). Furthermore, three of the FDA-approved siRNA therapeutics [patisiran, givosiran (Givlaari), and nedosiran] induce target mRNA degradation or cleavage via near-complete rather than complete base-pair complementarity. These features along with previous findings confound the currently held characteristics to distinguish siRNAs and miRNAs or biosimilars, of which all converge in the RNAi regulatory pathway action. Herein, we discuss the RNAi mechanism of action and current criteria for distinguishing between miRNAs and siRNAs while summarizing the common and unique chemistry and molecular pharmacology of the six FDA-approved siRNA therapeutics. The term "RNAi" therapeutics, as used previously, provides a coherently unified nomenclature for broader RNAi forms as well as the growing number of therapeutic siRNAs and miRNAs or biosimilars that best aligns with current pharmacological nomenclature by mechanism of action. SIGNIFICANCE STATEMENT: The common and unique chemistry and molecular pharmacology of six FDA-approved siRNA therapeutics are summarized, in which nedosiran is newly approved. We point out rather a surprisingly mechanistic action as miRNAs for five siRNA therapeutics and discuss the differences and similarities between siRNAs and miRNAs that supports using a general and unified term "RNAi" therapeutics to align with current drug nomenclature criteria in pharmacology based on mechanism of action and embraces broader forms and growing number of novel RNAi therapeutics.

Association between cardiometabolic index and controlled attenuation parameter in U.S. adults with NAFLD: findings from NHANES (2017-2020).

BACKGROUND: Cardiometabolic index (CMI), a novel indicator that combines abdominal obesity and lipid levels, has been confirmed to correlate with non-alcoholic fatty liver disease (NAFLD). However, limited research has been conducted on the relationship between CMI and controlled attenuation parameter (CAP), a parameter measured by transient elastography and reflecting the extent of fat accumulation in the liver. The objective of our study was to investigate the relationship between the two variables. METHODS: This was a cross-sectional study with a sample size of 1,759 U.S. adults with NAFLD sourced from the NHANES 2017-2020. Participants with a median CAP ≥ 248 dB/m were considered to have hepatic steatosis. CMI was calculated as [waist circumference (cm)/height(cm)]×[TG (mmol/L)/HDL-C (mmol/L)]. Multivariate linear regression, generalized additive model and subgroup analysis were employed to examine the association of CMI and CAP. RESULTS: The average age of the 1,759 participants was 50.2 years, with males accounting for 50.76% and females 49.24%. The average BMI was 32.23 kg/m². The multivariate linear regression model indicated that with every 1-unit increase in CMI, there was an associated rise of 10.40 dB/m in CAP (95% CI, 7.14-13.67) after adjusting for covariates and a p for trend < 0.05 suggested the existence of a linear association between the two variables. Similarly, generalized additive model also found it a roughly linear relationship between the two. Subgroup analysis revealed a positive correlation in the majority of subgroups. CONCLUSIONS: CMI was positively associated with CAP in U.S. adults with NAFLD. Our findings indicated that CMI may serve as an ideal indicator for monitoring the degree of hepatic steatosis among patients with NAFLD.

RNAi-Based Therapeutics and Novel RNA Bioengineering Technologies.

RNA interference (RNAi) provides researchers with a versatile means to modulate target gene expression. The major forms of RNAi molecules, genome-derived microRNAs (miRNAs) and exogenous small interfering RNAs (siRNAs), converge into RNA-induced silencing complexes to achieve posttranscriptional gene regulation. RNAi has proven to be an adaptable and powerful therapeutic strategy where advancements in chemistry and pharmaceutics continue to bring RNAi-based drugs into the clinic. With four siRNA medications already approved by the US Food and Drug Administration (FDA), several RNAi-based therapeutics continue to advance to clinical trials with functions that closely resemble their endogenous counterparts. Although intended to enhance stability and improve efficacy, chemical modifications may increase risk of off-target effects by altering RNA structure, folding, and biologic activity away from their natural equivalents. Novel technologies in development today seek to use intact cells to yield true biologic RNAi agents that better represent the structures, stabilities, activities, and safety profiles of natural RNA molecules. In this review, we provide an examination of the mechanisms of action of endogenous miRNAs and exogenous siRNAs, the physiologic and pharmacokinetic barriers to therapeutic RNA delivery, and a summary of the chemical modifications and delivery platforms in use. We overview the pharmacology of the four FDA-approved siRNA medications (patisiran, givosiran, lumasiran, and inclisiran) as well as five siRNAs and several miRNA-based therapeutics currently in clinical trials. Furthermore, we discuss the direct expression and stable carrier-based, in vivo production of novel biologic RNAi agents for research and development. SIGNIFICANCE STATEMENT: In our review, we summarize the major concepts of RNA interference (RNAi), molecular mechanisms, and current state and challenges of RNAi drug development. We focus our discussion on the pharmacology of US Food and Drug Administration-approved RNAi medications and those siRNAs and miRNA-based therapeutics that entered the clinical investigations. Novel approaches to producing new true biological RNAi molecules for research and development are highlighted.

Recombinant Technologies Facilitate Drug Metabolism, Pharmacokinetics, and General Biomedical Research.

The development of safe and effective medications requires a profound understanding of their pharmacokinetic (PK) and pharmacodynamic properties. PK studies have been built through investigation of enzymes and transporters that drive drug absorption, distribution, metabolism, and excretion (ADME). Like many other disciplines, the study of ADME gene products and their functions has been revolutionized through the invention and widespread adoption of recombinant DNA technologies. Recombinant DNA technologies use expression vectors such as plasmids to achieve heterologous expression of a desired transgene in a specified host organism. This has enabled the purification of recombinant ADME gene products for functional and structural characterization, allowing investigators to elucidate their roles in drug metabolism and disposition. This strategy has also been used to offer recombinant or bioengineered RNA (BioRNA) agents to investigate the posttranscriptional regulation of ADME genes. Conventional research with small noncoding RNAs such as microRNAs (miRNAs) and small interfering RNAs has been dependent on synthetic RNA analogs that are known to carry a range of chemical modifications expected to improve stability and PK properties. Indeed, a novel transfer RNA fused pre-miRNA carrier-based bioengineering platform technology has been established to offer consistent and high-yield production of unparalleled BioRNA molecules from Escherichia coli fermentation. These BioRNAs are produced and processed inside living cells to better recapitulate the properties of natural RNAs, representing superior research tools to investigate regulatory mechanisms behind ADME. SIGNIFICANCE STATEMENT: This review article summarizes recombinant DNA technologies that have been an incredible boon in the study of drug metabolism and PK, providing investigators with powerful tools to express nearly any ADME gene products for functional and structural studies. It further overviews novel recombinant RNA technologies and discusses the utilities of bioengineered RNA agents for the investigation of ADME gene regulation and general biomedical research.

The Misdiagnosis of Intravesical Ectopic Prostatic Tissue as a Tumor.

Ectopic prostatic tissue is rare, and it is usually only discovered by chance during imaging examinations or surgery. However, between 1967 and 2021, reports of ectopic prostatic tissue in the medical literature increased. It is rarely reported that ectopic prostatic tissue can be misdiagnosed as a nephrogenic adenoma (NA). This case study aimed to increase the awareness of ectopic prostatic tissue to improve its rates of diagnosis. This paper is focused on a 45-year-old male patient with a history of bladder lesions that were accidentally discovered through a health examination. A computed tomography scan revealed a homogeneous isoechoic mass in the posterior inferior wall of the bladder. At first, a transurethral cystoscopy revealed a smooth sessile mass covering the normal bladder mucosa, which was located in the middle of the interureteric ridge. The biopsy results suggested a possible intravesical NA. The mass was then completely resected under pneumovesicoscopy, and the pathological diagnosis was ectopic prostatic tissue. The clinical symptoms of ectopic prostatic tissue are similar to other bladder neoplasms, but there are too few characteristics available in imaging examinations to allow for an accurate diagnosis. Since ectopic prostatic tissue can present as a tumor in the bladder, urologists may easily misdiagnose the condition. Surgery is the basis of treatment for ectopic prostatic tissue, and it has a good prognosis.

The association between obstructive sleep apnea and lung nodule, carcinoembryonic antigen.

PURPOSE: The association between obstructive sleep apnea (OSA) and cancer risks gaining more and more attention. Data on the association between OSA and lung cancer risk are limited. This study is to investigate whether a link exists between low-dose computed tomography (LDCT) scanning of the chest findings, carcinoembryonic antigen (CEA) and OSA in patients suspected of OSA. METHODS: The cross-sectional study included patients aged 18 years or older who underwent continuous nocturnal polysomnography at our sleep center between February 2019 and November 2020. All subjects underwent chest LDCT and CEA. Patients with an apnea-hypopnea index (AHI) of ≥ 15/h were classified as clinically significant OSA group, whereas patients with an AHI < 15/h were classified as control group. RESULTS: A total of 277 patients were enrolled in the study. 176 patients were categorized into the OSA group, while 101 patients were categorized into the control group. There is no relationship between any OSA-related parameter and presence of lung nodule or presence of ≥ 6 mm lung nodule in the binary logistic regression analysis. OSA group demonstrated a significant higher value of CEA than control group. Stepwise multiple linear regression analysis showed that lowest O2 saturation (ß = - 0.256, p < 0.001), smoking status (ß = 0.156, p = 0.007) and age (ß = 0.153, p = 0.008) were independent predictors of elevated CEA. CONCLUSIONS: OSA was independently related to the elevated of serum CEA level, but not with presence of pulmonary nodule or ≥ 6 mm pulmonary nodule in LDCT. Further well-designed longitudinal studies with pathology available are needed to identify the association between OSA and risk of lung cancer.

Diabetes mellitus in patients with type 1 autoimmune pancreatitis at diagnosis and after corticosteroid therapy.

BACKGROUND: A high prevalence of diabetes mellitus (DM) coexisting with autoimmune pancreatitis (AIP) is observed. However, evidence on the circumstances under which corticosteroid therapy (CST) for AIP improves or worsens DM is scarce. This study aimed to demonstrate and identify predictors of DM control under the influence of CST. METHODS: Patients diagnosed with type 1 AIP were enrolled from a prospectively maintained cohort and were classified into three groups according to the chronology in which AIP and DM were diagnosed: pre-existing DM (pDM), concurrent DM (cDM), and non-DM (nDM). The responses of DM to CST were assessed when corticosteroid was ceased or tapered to a maintenance dose and classified as 'improvement' and 'non-improvement' (including 'no change' and 'exacerbation'). RESULTS: Among 101 patients with type 1 AIP, 52 (51.5%) patients were complicated with DM at the time of AIP diagnosis, with 36 patients in the cDM group and 16 patients in the pDM group. The incidences of diffuse pancreatic swelling (72.2%) and pancreatic body/tail involvement (91.7%) were significantly higher in the cDM group than in both the pDM and nDM groups. Of the 52 patients with DM, CST was administered in 48 cases. Multivariate logistic analysis identified that elevated serum gamma-glutamyl transferase (GGT) level at AIP diagnosis [odds ratio (OR) = 0.032, 95% confidence interval (CI): 0.003-0.412, P = 0.008] and pancreatic atrophy after CST (OR = 0.027, 95% CI: 0.003-0.295, P = 0.003) were negatively associated with DM control improvement. CONCLUSIONS: Patients with diffuse pancreatic swelling and pancreatic body/tail involvement in pancreatitis tended to be complicated with cDM at AIP diagnosis. CST exerted a beneficial effect on the clinical course of DM in nearly half of the AIP patients complicated with DM at diagnosis, particularly in those without elevated serum GGT levels at diagnosis and who did not experience pancreatic atrophy after CST.

RNA Drugs and RNA Targets for Small Molecules: Principles, Progress, and Challenges.

RNA-based therapies, including RNA molecules as drugs and RNA-targeted small molecules, offer unique opportunities to expand the range of therapeutic targets. Various forms of RNAs may be used to selectively act on proteins, transcripts, and genes that cannot be targeted by conventional small molecules or proteins. Although development of RNA drugs faces unparalleled challenges, many strategies have been developed to improve RNA metabolic stability and intracellular delivery. A number of RNA drugs have been approved for medical use, including aptamers (e.g., pegaptanib) that mechanistically act on protein target and small interfering RNAs (e.g., patisiran and givosiran) and antisense oligonucleotides (e.g., inotersen and golodirsen) that directly interfere with RNA targets. Furthermore, guide RNAs are essential components of novel gene editing modalities, and mRNA therapeutics are under development for protein replacement therapy or vaccination, including those against unprecedented severe acute respiratory syndrome coronavirus pandemic. Moreover, functional RNAs or RNA motifs are highly structured to form binding pockets or clefts that are accessible by small molecules. Many natural, semisynthetic, or synthetic antibiotics (e.g., aminoglycosides, tetracyclines, macrolides, oxazolidinones, and phenicols) can directly bind to ribosomal RNAs to achieve the inhibition of bacterial infections. Therefore, there is growing interest in developing RNA-targeted small-molecule drugs amenable to oral administration, and some (e.g., risdiplam and branaplam) have entered clinical trials. Here, we review the pharmacology of novel RNA drugs and RNA-targeted small-molecule medications, with a focus on recent progresses and strategies. Challenges in the development of novel druggable RNA entities and identification of viable RNA targets and selective small-molecule binders are discussed. SIGNIFICANCE STATEMENT: With the understanding of RNA functions and critical roles in diseases, as well as the development of RNA-related technologies, there is growing interest in developing novel RNA-based therapeutics. This comprehensive review presents pharmacology of both RNA drugs and RNA-targeted small-molecule medications, focusing on novel mechanisms of action, the most recent progress, and existing challenges.

Nuclear receptor RORγ inverse agonists/antagonists display tissue- and gene-context selectivity through distinct activities in altering chromatin accessibility and master regulator SREBP2 occupancy.

The nuclear receptor RORγ is a major driver of autoimmune diseases and certain types of cancer due to its aberrant function in T helper 17 (Th17) cell differentiation and tumor cholesterol metabolism, respectively. Compound screening using the classic receptor-coactivator interaction perturbation scheme led to identification of many small-molecule modulators of RORγ(t). We report here that inverse agonists/antagonists of RORγ such as VTP-43742 derivative VTP-23 and TAK828F, which can potently inhibit the inflammatory gene program in Th17 cells, unexpectedly lack high potency in inhibiting the growth of TNBC tumor cells. In contrast, antagonists such as XY018 and GSK805 that strongly suppress tumor cell growth and survival display only modest activities in reducing Th17-related cytokine expression. Unexpectedly, we found that VTP-23 significantly induces the cholesterol biosynthesis program in TNBC cells. Our further mechanistic analyses revealed that VTP-23 enhances the local chromatin accessibility, H3K27ac mark and the cholesterol master regulator SREBP2 recruitment at the RORγ binding sites, whereas XY018 exerts the opposite activities. Yet, they display similar inhibitory effects on circadian rhythm program. Similar distinctions and contrasting activities between TAK828F and SR2211 in their effects on local chromatin structure at Il17 genes were also observed. Together, our study shows for the first-time that structurally distinct RORγ antagonists possess different or even contrasting activities in tissue/cell-specific manner. Our findings also highlight that the activities at natural chromatin are key determinants of RORγ modulators' tissue selectivity.

Examining the impact of multilevel upper airway surgery on the obstructive sleep apnoea endotypes and their utility in predicting surgical outcomes.

BACKGROUND AND OBJECTIVE: Upper airway surgery for obstructive sleep apnoea (OSA) is an alternative treatment for patients who are intolerant of continuous positive airway pressure (CPAP). However, upper airway surgery has variable treatment efficacy with no reliable predictors of response. While we now know that there are several endotypes contributing to OSA (i.e., upper airway collapsibility, airway muscle response/compensation, respiratory arousal threshold and loop gain), no study to date has examined: (i) how upper airway surgery affects all four OSA endotypes, (ii) whether knowledge of baseline OSA endotypes predicts response to surgery and (iii) whether there are any differences when OSA endotypes are measured using the CPAP dial-down or clinical polysomnographic (PSG) methods. METHODS: We prospectively studied 23 OSA patients before and ≥3 months after multilevel upper airway surgery. Participants underwent clinical and research PSG to measure OSA severity (apnoea-hypopnoea index [AHI]) and endotypes (measured in supine non-rapid eye movement [NREM]). Values are presented as mean ± SD or median (interquartile range). RESULTS: Surgery reduced the AHITotal (38.7 [23.4 to 79.2] vs. 22.0 [13.3 to 53.5] events/h; p = 0.009). There were no significant changes in OSA endotypes, however, large but variable improvements in collapsibility were observed (CPAP dial-down method: ∆1.9 ± 4.9 L/min, p = 0.09, n = 21; PSG method: ∆3.4 [-2.8 to 49.0]%Veupnoea , p = 0.06, n = 20). Improvement in collapsibility strongly correlated with improvement in AHI (%∆AHISupineNREM vs. ∆collapsibility: p < 0.005; R2  = 0.46-0.48). None of the baseline OSA endotypes predicted response to surgery. CONCLUSION: Surgery unpredictably alters upper airway collapsibility but does not alter the non-anatomical endotypes. There are no baseline predictors of response to surgery.

Changes of retinal ganglion cell complex after vitrectomy in rhegmatogenous retinal detachment patients and its correlation with inflammatory blood biomarkers.

PURPOSE: To compare retinal ganglion cell complex (GCC) parameters between rhegmatogenous retinal detachment (RRD) eyes and normal contralateral eyes after vitrectomy and to evaluate their correlation with inflammatory blood markers. METHODS: We investigated 25 eyes that underwent vitrectomy due to RRD. Venous blood samples were collected from all participants before 08:00 a.m. on the second day of admission after a 12-hour fast for blood counts. The differences of retinal structure between RRD and contralateral eyes were compared 1 week postoperatively. RESULTS: Focal loss volume (FLV) (2.009 ± 1.286)% was significantly increased compared with the contralateral eyes (p <  0.001). Monocyte-to-high-density lipoprotein was significantly positively correlated with GCC thickness parameters, and negatively correlated with FLV and global loss volume (GLV). Postoperative best-corrected visual acuity was negatively correlated with GLV (p = 0.039, R2 = 0.172). CONCLUSION: Retinal ganglion cells (RGCs) loss might present early postoperatively in RRD eyes, and was associated with systemic inflammation. RGCs loss might affect postoperative vision.

Long non-coding RNA MALAT1 affects intermittent hypoxia-induced endothelial injury by regulating miR-142-3p/HMGB1.

BACKGROUND: Obstructive sleep apnea (OSA) is a risk factor for atherosclerosis. Long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is strongly linked to endothelial cell functions. However, the function of MALAT1 in intermittent hypoxia (IH) associated vascular endothelial injury has not been explored yet. The current study makes great attempts to investigate the function of MALAT1 in IH-induced endothelial injury and its latent control network. METHODS: To mimic the effect of OSA, we cultured the human umbilical vein endothelial cells (HUVECs) under intermittent hypoxia. Western blot was applied to measure the expression level of associated proteins including capase-3, Bax, Bcl-2 while qRT-PCR was used in measurement of MALAT1 and miR-142-3p. Cell Counting Kit-8 (CCK-8) was carried out in assessing cell viability. Dual-luciferase reporter assay was applied to verify the relationships among high mobility group box (HMGB)1 and MALAT1, miR-142-3p. RESULTS: IH treatment significantly reduced cell viability but enhanced cell apoptosis in HUVECs. Concomitantly, MALAT1 was significantly upregulated in IH-treated HUVECs. Further experiment showed that MALAT1 knockdown augmented IH-induced injury of HUVECs. In addition, it was confirmed by dual-luciferase reporter assay that MALAT1 interacted with miR-142-3p directly. Besides, inhibition of miR-142-3p alleviated damage induced by MALAT1 knockdown in IH-treated HUVECs. Finally, miR-142-3p interacted with HMGB1 directly and inhibition of HMGB1 protein expression mediated by MALAT1 knockdown was reversed by miR-142-3p inhibitor. CONCLUSIONS: IH resulted in increased expression of MALAT1 in HUVECs. MALAT1 knockdown augmented IH-induced injury of HUVECs. MALAT1 exerted its effects on IH-treated HUVECs via miR-142-3p/HMGB1.

Obstructive sleep apnea and the risk of mortality in patients with lung cancer: a meta-analysis.

PURPOSE: Prior reports have examined the relationship between obstructive sleep apnea (OSA) and the mortality rate of lung cancer. However, the findings remain controversial. The present meta-analysis was performed to assess the relationship between OSA and increased risk of mortality in patients with lung cancer. METHODS: PubMed, Web of Science, and Embase were systematically searched for the correlative studies. Data were analyzed and pooled to evaluate odds ratios (ORs) of lung cancer mortality related to OSA. RESULTS: From 249 identified studies, 3 met inclusion criteria and were analyzed, including 67 patients with lung cancer and comorbid OSA and 45 patients with lung cancer and no OSA. The meta-analysis indicated that OSA was not significantly correlated with mortality rate in lung cancer (OR = 2.005, 95% CI = 0.703 to 5.715, z = 1.30, p = 0.193). There was no significant publication bias according to Begg's tests (p = 0.296) and Egger's tests (p = 0.097). CONCLUSION: This meta-analysis suggests that OSA is not significantly correlated with the mortality rate in lung cancer.

[Aberrant Expression and Glycosylation of Mucins in Gastric Mucosal Disease].

Mucins,a family of heavily glycosylated proteins,present mainly in epithelial cells.They function as essential barriers for epithelium and play important roles in cellular physiological processes.Aberrant expression and glycosylation of mucins in gastric epithelium occur at pathological conditions,such as Helicobacter pylori infection,chronic atrophic gastritis,intestinal metastasis,dysplasia,and gastric cancer.This review addresses the major roles played by mucins and associated O-glycan structures in normal gastric epithelium.Further,we expound the alterations of expression patterns and glycan signatures of mucins at those pathological conditions.

A Novel Integrated Pharmacokinetic-Pharmacodynamic Model to Evaluate Combination Therapy and Determine In Vivo Synergism.

Understanding pharmacokinetic (PK)-pharmacodynamic (PD) relationships is essential in translational research. Existing PK-PD models for combination therapy lack consideration of quantitative contributions from individual drugs, whereas interaction factor is always assigned arbitrarily to one drug and overstretched for the determination of in vivo pharmacologic synergism. Herein, we report a novel generic PK-PD model for combination therapy by considering apparent contributions from individual drugs coadministered. Doxorubicin (Dox) and sorafenib (Sor) were used as model drugs whose PK data were obtained in mice and fit to two-compartment model. Xenograft tumor growth was biphasic in mice, and PD responses were described by three-compartment transit models. This PK-PD model revealed that Sor (contribution factor = 1.62) had much greater influence on overall tumor-growth inhibition than coadministered Dox (contribution factor = 0.644), which explains the mysterious clinical findings on remarkable benefits for patients with cancer when adding Sor to Dox treatment, whereas there were none when adding Dox to Sor therapy. Furthermore, the combination index method was integrated into this predictive PK-PD model for critical determination of in vivo pharmacologic synergism that cannot be correctly defined by the interaction factor in conventional models. In addition, this new PK-PD model was able to identify optimal dosage combination (e.g., doubling experimental Sor dose and reducing Dox dose by 50%) toward much greater degree of tumor-growth inhibition (>90%), which was consistent with stronger synergy (combination index = 0.298). These findings demonstrated the utilities of this new PK-PD model and reiterated the use of valid method for the assessment of in vivo synergism. SIGNIFICANCE STATEMENT: A novel pharmacokinetic (PK)-pharmacodynamic (PD) model was developed for the assessment of combination treatment by considering contributions from individual drugs, and combination index method was incorporated to critically define in vivo synergism. A greater contribution from sorafenib to tumor-growth inhibition than that of coadministered doxorubicin was identified, offering explanation for previously inexplicable clinical observations. This PK-PD model and strategy shall have broad applications to translational research on identifying optimal dosage combinations with stronger synergy toward improved therapeutic outcomes.

Quantum frequency conversion from ultraviolet to visible band through waveguides in a period-poled MgO:LiTaO3 crystal.

In research on hybrid quantum networks, visible or near-infrared frequency conversion has been realized. However, technical limitations mean that there have been few studies involving the ultraviolet band, and unfortunately the wavelengths of the rare-earth or alkaline-earth metal atoms or ions that are used widely in research on quantum information are often in the UV band. Therefore, frequency conversion of the ultraviolet band is very important. In this paper, we demonstrate a quantum frequency conversion between ultraviolet and visible wavelengths by fabricating waveguides in a period-poled MgO:LiTaO3 crystal with a laser writing system, which will be used to connect the wavelength of the dipole transition of 171Yb+ at 369.5 nm and the absorption wavelength of Eu3+ at 580 nm in a solid-state quantum memory system. An external conversion efficiency of 0.85% and a signal-to-noise ratio of greater than 500 are realized with a pumping power of 3.28 W at 1018 nm. Furthermore, we complete frequency conversion of the classical polarization state by means of a symmetric optical setup based on the fabricated waveguide, and the process fidelity of the conversion is (96.13 ± 0.021)%. This converter paves the way for constructing a hybrid quantum network and realizing a quantum router in the ultraviolet band in the future.

Large-tuning-range frequency stabilization of an ultraviolet laser by an open-loop piezoelectric ceramic controlled Fabry-Pérot cavity.

We demonstrate a laser frequency stabilization method with large tuning range to stabilize a UV laser by installing piezoelectric ceramic actuators into a Fabry-Pérot cavity with an ultra-low expansion spacer. To suppress piezoelectric drift, a two-layer symmetrical structure is adopted for the piezoelectric actuator, and a 14.7 GHz tuning range is achieved. The short-term drift of the piezoelectric ceramics caused by temperature and creep is eliminated, and the long-term drift is 0.268 MHz/h when the Fabry-Pérot cavity is sealed in a chamber without a vacuum environment. The long-term frequency drift is mainly caused by stress release and is eliminated by compensating the cavity voltage with an open loop. Without the need for an external reference or a vacuum environment, the laser frequency stabilization system is greatly simplified, and it can be extended to wavelengths ranging from ultraviolet to infrared. Owing to its simplicity, stability, and large tuning range, it is applicable in cold atom and trapped ion experiments.

Super-resolved Imaging of a Single Cold Atom on a Nanosecond Timescale.

In cold atomic systems, fast and high-resolution microscopy of individual atoms is crucial, since it can provide direct information on the dynamics and correlations of the system. Here, we demonstrate nanosecond-scale two-dimensional stroboscopic pictures of a single trapped ion beyond the optical diffraction limit, by combining the main idea of ground-state depletion microscopy with quantum-state transition control in cold atoms. We achieve a spatial resolution up to 175 nm using a NA=0.1 objective in the experiment, which represents a more than tenfold improvement compared with direct fluorescence imaging. To show the potential of this method, we apply it to observe the secular motion of the trapped ion; we demonstrate a temporal resolution up to 50 ns with a displacement detection sensitivity of 10 nm. Our method provides a powerful tool for probing particle positions, momenta, and correlations, as well as their dynamics in cold atomic systems.

Defining the endoscopic ultrasound features of chronic pancreatitis in Asians: a multicenter validation study.

BACKGROUND: Although endoscopic ultrasound (EUS) features and criteria have been described in chronic pancreatitis, challenges remain with interoperator variability and ease of adoption. The aim of this study was to define and validate the EUS features of chronic pancreatitis in a multicenter prospective study in Asia. METHOD: The study was divided into two parts: the first part was conducted to derive the EUS features of chronic pancreatitis with adequate interoperator agreement; the second was to prospectively evaluate these features in a multicenter cross-sectional study and determine the optimal combination of features for the diagnosis of chronic pancreatitis. Prospectively enrolled cases had standard internationally validated radiologic or histologic features of chronic pancreatitis, and controls were patients without chronic pancreatitis who underwent EUS examination. RESULTS: The top six EUS features that had good interobserver agreement (mean kappa 0.73, range 0.60 - 0.90) were selected to be further evaluated in part II of the study. These included: hyperechoic foci with shadowing, lobularity with honeycombing, cysts, dilated main pancreatic duct, dilated side branches, and calculi in the main pancreatic duct. A total of 284 subjects (132 cases, 152 controls) were enrolled from 12 centers in Asia. All six features had high accuracy ranging from 63.3 % to 89.1 %. Two or more of these six EUS features accurately defined chronic pancreatitis (sensitivity 94.7 %, specificity 98.0 %), with an area under the receiver operating curve of 0.986. CONCLUSION: This multicenter Asian study characterized and defined the EUS features of chronic pancreatitis. This provides a useful tool in clinical practice and further research in pancreatic cancer surveillance.