Heralded Three-Photon Entanglement from a Single-Photon Source on a Photonic Chip

In the quest to build general-purpose photonic quantum computers, fusion-based quantum computation has risen to prominence as a promising strategy. This model allows a ballistic construction of large cluster states which are universal for quantum computation, in a scalable and loss-tolerant way without feed forward, by fusing many small n-photon entangled resource states. However, a key obstacle to this architecture lies in efficiently generating the required essential resource states on photonic chips. One such critical seed state that has not yet been achieved is the heralded three-photon Greenberger-Horne-Zeilinger (3-GHZ) state. Here, we address this elementary resource gap, by reporting the first experimental realization of a heralded 3-GHZ state. Our implementation employs a low-loss and fully programmable photonic chip that manipulates six indistinguishable single photons of wavelengths in the telecommunication regime. Conditional on the heralding detection, we obtain the desired 3-GHZ state with a fidelity 0.573±0.024. Our Letter marks an important step for the future fault-tolerant photonic quantum computing, leading to the acceleration of building a large-scale optical quantum computer.

A Phase 1 Study of the DNA-PK Inhibitor Peposertib in Combination With Radiation Therapy With or Without Cisplatin in Patients With Advanced Head and Neck Tumors

PURPOSE

DNA-dependent protein kinase (DNA-PK) plays a key role in the repair of DNA double strand breaks via nonhomologous end joining. Inhibition of DNA-PK can enhance the effect of DNA double strand break inducing anticancer therapies. Peposertib (formerly "M3814") is an orally administered, potent, and selective small molecule DNA-PK inhibitor that has demonstrated radiosensitizing and antitumor activity in xenograft models and was well-tolerated in monotherapy. This phase 1 trial (National Clinical Trial 02516813) investigated the maximum tolerated dose, recommended phase 2 dose (RP2D), safety, and tolerability of peposertib in combination with palliative radiation therapy (RT) in patients with thoracic or head and neck tumors (arm A) and of peposertib in combination with cisplatin and curative-intent RT in patients with squamous cell carcinoma of the head and neck (arm B).

METHODS AND MATERIALS

Patients received peposertib once daily in ascending dose cohorts as a tablet or capsule in combination with palliative RT (arm A) or in combination with intensity modulated curative-intent RT and cisplatin (arm B).

RESULTS

The most frequently observed treatment-emergent adverse events were radiation skin injury, fatigue, and nausea in arm A (n = 34) and stomatitis, nausea, radiation skin injury, and dysgeusia in arm B (n = 11). Based on evaluations of dose-limiting toxicities, tolerability, and pharmacokinetic data, RP2D for arm A was declared as 200 mg peposertib tablet once daily in combination with RT. In arm B (n = 11), 50 mg peposertib was declared tolerable in combination with curative-intent RT and cisplatin. However, enrollment was discontinued because of insufficient exposure at that dose, and the RP2D was not formally declared.

CONCLUSIONS

Peposertib in combination with palliative RT was well-tolerated up to doses of 200 mg once daily as tablet with each RT fraction. When combined with RT and cisplatin, a tolerable peposertib dose yielded insufficient exposure.

A Phase Ib Study of the DNA-PK Inhibitor Peposertib Combined with Neoadjuvant Chemoradiation in Patients with Locally Advanced Rectal Cancer

PURPOSE

Peposertib-an orally administered DNA-dependent protein kinase inhibitor-has shown potent radiosensitization in preclinical models. This dose-escalation study (NCT03770689) aimed to define the maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of peposertib plus capecitabine-based chemoradiotherapy (CRT) and assessed its safety and efficacy in locally advanced rectal cancer.

PATIENTS AND METHODS

Patients were treated for 5 to 5.5 weeks with 50- to 250-mg peposertib once daily, capecitabine 825 mg/m2 twice daily, and radiotherapy (RT), 5 days per week. Following clinical restaging (8 weeks after CRT completion), patients with clinical complete response (cCR) could opt for surveillance. Total mesorectal excision was recommended upon incomplete response (IR).

RESULTS

Nineteen patients were treated with peposertib at doses of 50 mg (n = 1), 100 mg, 150 mg, and 250 mg (n = 6 each). Dose-limiting toxicities occurred in one out of five (100 mg), one out of six (150 mg), and three out of six (250 mg) evaluable patients. Peposertib ≤150 mg once daily was tolerable in combination with CRT. After 8 weeks of treatment with peposertib and CRT, the cCR was 15.8% (n = 3). Among the three patients with cCR, two underwent surgery and had residual tumors. Among the 16 patients with IR, seven underwent surgery and had residual tumors; five of the remaining nine patients opted for consolidative chemotherapy. The combined cCR/pathologic complete response (pCR) rate was 5.3% (n = 1, 100 mg cohort).

CONCLUSIONS

Peposertib did not improve complete response rates at tolerable dose levels. The study was closed without declaring the MTD/RP2D.

Phase I crossover study of DNA-protein kinase inhibitor peposertib in healthy volunteers: Effect of food and pharmacokinetics of an oral suspension

Peposertib is an orally administered inhibitor of DNA-dependent protein kinase. We evaluated the effect of food on its pharmacokinetics, and examined the pharmacokinetics of an oral suspension (OS) of disintegrated tablets, in a phase I, open-label, crossover three-period study (NCT04702698). Twelve healthy volunteers were randomized to one of six treatment sequences. They received a single dose of peposertib 100 mg as film-coated tablets under fasted or fed conditions ("tablet fasted" or "tablet fed") or as an OS under fasted conditions ("OS fasted"), with washout between treatments. Using healthy volunteers was possible because, despite its mechanism of action being suppression of DNA repair, peposertib has shown no genotoxic effect in animals. A mild food effect was observed with peposertib tablets. Fed-to-fasted ratios were: area under the curve from time 0 to time t (AUC0-t ), 123.81% (90% confidence interval [CI]: 108.04, 141.87%); AUC from zero to infinity (AUC0-∞ ), 110.28% (90% CI 100.71, 120.77%); and maximum concentration (Cmax ) 104.47% (90% CI: 79.15, 137.90%). Cmax was delayed under fed conditions (median time to maximum concentration [Tmax ] was 3.5 h [tablet fed] vs. 1 h [tablet fasted]). OS-to-tablet (fasted) ratios were: AUC0-t , 124.83% (90% CI: 111.50%, 139.76%); AUC0-∞ , 119.05% (90% CI: 104.47, 135.67%); and Cmax 173.29% (90% CI: 135.78, 221.16%). Median Tmax was 0.5 h (OS fasted) versus 1 h (tablet). All treatments were well-tolerated in healthy volunteers. Peposertib tablets can be taken with or without food; if combined with chemotherapy or radiotherapy, the delay in Cmax must be considered to optimize the chemo- or radiosensitizing effect. The peposertib OS form represents an alternative route of administration in patients with specific cancers causing dysphagia. However, the OS form should be part of future dose optimization strategies in relevant settings.

Brainmask: an ultrasoft and moist micro-electrocorticography electrode for accurate positioning and long-lasting recordings

Bacterial cellulose (BC), a natural biomaterial synthesized by bacteria, has a unique structure of a cellulose nanofiber-weaved three-dimensional reticulated network. BC films can be ultrasoft with sufficient mechanical strength, strong water absorption and moisture retention and have been widely used in facial masks. These films have the potential to be applied to implantable neural interfaces due to their conformality and moisture, which are two critical issues for traditional polymer or silicone electrodes. In this work, we propose a micro-electrocorticography (micro-ECoG) electrode named "Brainmask", which comprises a BC film as the substrate and separated multichannel parylene-C microelectrodes bonded on the top surface. Brainmask can not only guarantee the precise position of microelectrode sites attached to any nonplanar epidural surface but also improve the long-lasting signal quality during acute implantation with an exposed cranial window for at least one hour, as well as the in vivo recording validated for one week. This novel ultrasoft and moist device stands as a next-generation neural interface regardless of complex surface or time of duration.

A215 EVALUATING THE COMPARABILITY OF CARE FOR PERSONS ADMITTED TO TORONTO AREA HOSPITALS WITH ACUTE SEVERE ULCERATIVE COLITIS

Background

Approximately 20% of patients with ulcerative colitis will experience an acute severe exacerbation requiring hospitalization. Acute severe ulcerative colitis (ASUC) is a medical emergency associated with significant morbidity and a mortality rate of 1%. Timely initiation of treatment and assessment of clinical response is critical in the management of ASUC. With an aim to reduce treatment variability and improve outcomes, multiple gastrointestinal societies have published guidelines highlighting recommendations for optimal care in ASUC. It remains unclear how closely these guidelines are implemented in clinical practice. Measuring adherence to these recommended processes of care may act as a surrogate measure for quality of care and a way to indirectly evaluate outcomes in the management of patients with ASUC. Studies have shown that even amongst experienced providers practice pattern variability exists. Identifying significant variations in the management of patients with ASUC will highlight where improvement in guideline dissemination and greater adherence is required.

Purpose

We sought to evaluate how quality of care indicators varied across 7 hospital sites for patients admitted ASUC in the Greater Toronto Area.

Method

Using GEMINI, a research collaborative that collects and analyses data from inpatient admissions at 7 Toronto area hospitals, we identified patients admitted to hospital with ASUC from June 2016-December 2019. Hospital sites were further categorized into 3 hospital types; 1 IBD specialty centre (ISC), 3 other academic centres (AC) and 3 community centres (CC). Process measures assessed included proportion tested for C-reactive protein at baseline and following treatment initiation, duration of corticosteroid use, timing and initiation of biologic agents, rates of venous thromboembolism prophylaxis and opioid use. Outcome measures included hospital length of stay, rates of colectomy and mortality.

Result(s)

765 hospitalizations were included in the study; 320 occurring at ISC, 308 at AC and 137 at CC. Corticosteroid use on admission were highest at the ISC at 78% compared to 64% at AC and 63% at CC (p <0.001). Among those who received steroids on admission, 47% of patients remained on intravenous corticosteroids for at least 5 days in the ISC compared to 39% in AC and 75% in CC (p< 0.001). Initiation of biologic rescue therapy was highest at the ISC occurring in 37% of hospitalizations compared to 22% in AC and 23% in CC (p<0.001). In addition, VTE prophylaxis rates were highest at the ISC at 83% followed by 60% in AC and 45% in CC (p<0.001). Rates of colectomy were highest at ISC (12% of hospitalizations vs. 7% in AC).

Conclusion(s)

Greater adherence to indicators of quality of care were seen at the ISC compared to ACs and CCs, although patient outcomes assessed were not clearly different between sites. Further strategies are required to improve adherence to markers of quality care for patients admitted with ASUC.

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Disclosure of Interest

None Declared

Localized Surface Hydrophilicity Tailoring of Polyimide Film for Flexible Electronics Manufacturing Using an Atmospheric Pressure Ar/H2O Microplasma Jet

The poor hydrophilicity of polyimide (PI) films limits their applications in flexible electronics, such as in wearable and implantable bio-MEMS devices. In this paper, an atmospheric pressure Ar/H₂O microplasma jet (μAPPJ) with a nozzle diameter of 100 μm was utilized to site-selectively tune the surface hydrophilicity of a PI film. The electrical and optical characteristics of the μAPPJ were firstly investigated, and the results showed that multi-spikes occurred during the plasma discharge and that diverse reactive species, such as O atoms and OH radicals, were generated in the plasma plume. The physical and chemical properties of pristine and microplasma-modified PI surfaces were characterized by the water contact angle (WCA), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The wettability of the PI surface was significantly enhanced after microplasma modification, and the WCA could be adjusted by varying the applied voltage, water vapor content, plasma treatment time and storage time. The AFM images indicated that the surface roughness increased after the plasma treatment, which partially contributed to an improvement in the surface hydrophilicity. The XPS results showed a reduction in the C content and an increase in the O content, and abundant hydrophilic polar oxygen-containing functional groups were also grafted onto the PI film surface. Finally, the interaction mechanism between the PI molecular chains and the microplasma is discussed. The breaking of C-N and C-O bonds and the grafting of OH radicals were the key pathways to dominate the reaction process.

465 Bintrafusp alfa in combination with chemotherapy in patients with stage IV NSCLC: safety and pharmacokinetic results of the INTR@PID LUNG 024 study

Background

Bintrafusp alfa is a first-in-class bifunctional fusion protein composed of the extracellular domain of the TGF-βRII receptor (a TGF-β ”trap”) fused to a human IgG1 mAb blocking PD-L1. Here we report cumulative safety and pharmacokinetic (PK) results from the global, phase 1b/2 INTR@PID LUNG 024 study (NCT03840915), which evaluated bintrafusp alfa in combination with chemotherapy (CT) in patients with stage IV NSCLC.

Methods

Adult patients with stage IV nonsquamous or squamous NSCLC and an ECOG PS ≤1 were included. Cohorts A, B, and C included patients with no prior systemic therapy; patients in cohort D had disease that progressed with previous anti–PD-(L)1 therapy. Cohorts received bintrafusp alfa 2400 mg every 3 weeks intravenously in combination with CT for 4 cycles (A [nonsquamous only]: cisplatin or carboplatin + pemetrexed; B: carboplatin + nab-paclitaxel or paclitaxel; C: cisplatin or carboplatin + gemcitabine; D: docetaxel) followed by bintrafusp alfa maintenance (monotherapy or in combination with pemetrexed in cohort A) for up to 31 cycles. The primary objective of this study was to evaluate the safety of bintrafusp alfa in combination with CT. Dose-limiting toxicities (DLTs) were assessed during a 3-week observation period. Serial samples were drawn to assess serum concentration and calculate PK parameters by noncompartmental analysis.

Results

As of the May 5, 2021, data cutoff, 70 patients received bintrafusp alfa in combination with CT. Of 35 patients included in the DLT analysis, 4 experienced 1 DLT according to a safety monitoring committee (data cutoff May 5, 2021; A: n=1/8; B: n=1/8; C: n=0/8; D: n=2/11). Cumulative safety data are reported in table 1. PK data were available for 67 patients (A: n=38; B: n=9; C: n=8; D: n=12). PK profiles were similar across cohorts and between patients who did and did not experience a DLT. Observed bintrafusp alfa first-cycle exposures (Cmax, AUC, and Ctrough) were consistent with the published population PK (popPK) model.1

Abstract 465 Table 1

Safety results from the INTR@PID LUNG 024 study

Conclusions

The safety profile of bintrafusp alfa in combination with CT was manageable and similar to that reported for ICIs in combination with CT, with the exception of TGF-β–related skin lesions known to occur with TGF-β inhibition. No new safety signals were identified and there were no treatment-related deaths. The PK profile was consistent with the predicted monotherapy popPK model, suggesting no victim DDI potential for bintrafusp alfa with CT.

Acknowledgements

The authors thank the patients and their families, investigators, co-investigators, and the study teams at each of the participating centers, at the healthcare business of Merck KGaA, Darmstadt, Germany, and at EMD Serono, Billerica, Massachusetts, USA.

Trial Registration

NCT03840915

Reference

Wilkins JJ, Vugmeyster Y, Dussault I. Population pharmacokinetic analysis of bintrafusp alfa in different cancer types. Adv Ther 2019;36:2414–2433.

Ethics Approval

The trial was approved by each site’s independent ethics committee.

Cloning, genome structure and expression analysis of MHC class I gene in Korean quail

1. The major histocompatibility complex (MHC) is a highly polymorphic region of the genome essential to immune responses and animal health. However, avian MHC genetic structure is different from that of mammals. In this study, the structure and expression of Korean quail MHC class I gene was analysed.2. The quail MHC gene consisted of eight exons and seven introns. The open reading frame of the cDNA was 353 amino acids, and the molecular weight was about 38.91 kDa. Exons 1 and 2 coded for leading peptides and alpha 1 regions, respectively. Exons 3 and 4 encoded alpha 2 and alpha 3 regions. Exons 5 to 8 coded for connecting peptides and transmembrane regions/cytoplasmic regions (TM/CY). The Korean quail MHC class I amino acid sequence shared 87% to 99% homology with Japanese quail and 71% to 75% with chicken. The amino acid shared 40% and 43% homology with humans and mice, respectively.3. Real-time quantitative PCR showed that MHC-I was highly expressed in immune tissues such as the bursa of Fabricius. Moreover, the constructed evolutionary tree was consistent with accepted evolutionary pathways.4. MHC-I is closely related to the host's immune system, and these findings may help to better understand the role of Korean quail MHC-I in the immune system.

Knockdown of LINC00461 inhibits cell proliferation and induces apoptosis in gastric cancer by targeting LSD1

OBJECTIVE

To uncover the function of LINC00461 in regulating cellular behaviors of gastric cancer (GC) via targeting LSD1.

PATIENTS AND METHODS

LINC00461 level in GC tissues with different tumor node metastasis (TNM) staging and lymphatic metastasis statues was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). In vitro influences of LINC00461 on proliferative and apoptotic rates were evaluated in AGS and SGC-7901 cells. The interaction between LINC00461 and LSD1 was explored by RNA immunoprecipitation (RIP) assay and qRT-PCR. Finally, the potential role of LSD1 in the proliferative ability of GC cells mediated by LINC00461 was assessed.

RESULTS

LINC00461 level was higher in GC tissues relative to matched control ones. It was positively correlated to TNM staging and lymphatic metastasis of GC. Knockdown of LINC00461 markedly attenuated viability and the proliferative ability of AGS and SGC-7901 cells, but induced apoptosis. RIP assay demonstrated the interaction between LINC00461 and LSD1. Moreover, LSD1 could reverse the regulatory effect of LINC00461 on the proliferative ability of GC cells.

CONCLUSIONS

LINC00461 is upregulated in GC, which is positively related to TNM staging and lymphatic metastasis. LINC00461 mediates proliferation and apoptosis of GC cells, thereafter aggravating the progression of GC.

LncRNA PAPAS aggravates the progression of gastric cancer through regulating miRNA-188-5p

OBJECTIVE

To uncover the biological effect of long non-coding RNA (lncRNA) PAPAS on the progression of gastric cancer (GC) by mediating microRNA-188-5p (miRNA-188-5p) level.

PATIENTS AND METHODS

The relative level of PAPAS was determined in GC tissues and cell lines by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The Kaplan-Meier method was introduced to assess the prognostic potential of PAPAS in the overall survival of GC patients. Regulatory effects of PAPAS on proliferative, migratory, and invasive abilities of HGC-27 and AGS cells were detected by cell counting kit-8 (CCK-8), transwell, and wound closure assay, respectively. Subsequently, the binding relation between PAPAS and miRNA-188-5p was verified by the Dual-luciferase reporter gene assay. Correlation between expression levels of PAPAS and miRNA-188-5p in GC tissues was explored. Finally, rescue experiments were conducted to uncover the role of PAPAS/miRNA-188-5p axis in the progression of GC.

RESULTS

PAPAS was upregulated in GC tissues and cell lines compared to controls. GC patients expressing a high level of PAPAS suffered worse prognosis relative to those with low level. The silence of PAPAS remarkably attenuated proliferative, migratory, and invasive abilities of HGC-27 cells. Overexpression of PAPAS in AGS cells obtained the opposite trends. MiRNA-188-5p was the direct target of PAPAS, which was negatively regulated by PAPAS. MiRNA-188-5p was able to reverse the regulatory effects of PA-PAS on proliferative, migratory, and invasive abilities of GC cells.

CONCLUSIONS

LncRNA PAPAS is upregulated in GC and closely related to lymphatic metastasis, distant metastasis, and poor prognosis of GC patients. PAPAS aggravate the malignant progression of GC by negatively regulating the miRNA-188-5p level.

Mycoplasma pneumoniae lipids license TLR-4 for activation of NLRP3 inflammasome and autophagy to evoke a proinflammatory response

Mycoplasma pneumoniae is an obligate pathogen that causes pneumonia, tracheobronchitis, pharyngitis and asthma in humans. It is well recognized that membrane lipoproteins are immunostimulants exerting as lipopolysaccharides (LPS) and play a crucial role in the pathogenesis of inflammatory responses upon M. pneumoniae infection. Here, we report that the M. pneumoniae-derived lipids are another proinflammatory agents. Using an antibody-neutralizing assay, RNA interference or specific inhibitors, we found that Toll-like receptor 4 (TLR-4) is essential for M. pneumoniae lipid-induced tumour necrosis factor (TNF)-α and interleukin (IL)-1β production. We also demonstrate that NLR family pyrin domain containing 3 inflammasome (NLRP3) inflammasome, autophagy and nuclear factor kappa B (NF-κB)-dependent pathways are critical for the secretion of proinflammatory cytokines, while inhibition of TLR-4 significantly abrogates these events. Further characterization revealed that autophagy-mediated inflammatory responses involved the activation of NF-κB. In addition, the activation of NF-κB promoted lipid-induced autophagosome formation, as revealed by assays using pharmacological inhibitors, 3-methyladenine (3-MA) and Bay 11-7082, or silencing of atg5 and beclin-1. These findings suggest that, unlike the response to lipoprotein stimulation, the inflammation in response to M. pneumoniae lipids is mediated by the TLR-4 pathway, which subsequently initiates the activation of NLRP3 inflammasome and formation of a positive feedback loop between autophagy and NF-κB signalling cascade, ultimately promoting TNF-α and Il-1β production in macrophages.

Proteomic and Transcriptomic Changes in Hibernating Grizzly Bears Reveal Metabolic and Signaling Pathways that Protect against Muscle Atrophy

Muscle atrophy is a physiological response to disuse and malnutrition, but hibernating bears are largely resistant to this phenomenon. Unlike other mammals, they efficiently reabsorb amino acids from urine, periodically activate muscle contraction, and their adipocytes differentially responds to insulin. The contribution of myocytes to the reduced atrophy remains largely unknown. Here we show how metabolism and atrophy signaling are regulated in skeletal muscle of hibernating grizzly bear. Metabolic modeling of proteomic changes suggests an autonomous increase of non-essential amino acids (NEAA) in muscle and treatment of differentiated myoblasts with NEAA is sufficient to induce hypertrophy. Our comparison of gene expression in hibernation versus muscle atrophy identified several genes differentially regulated during hibernation, including Pdk4 and Serpinf1. Their trophic effects extend to myoblasts from non-hibernating species (including C. elegans), as documented by a knockdown approach. Together, these changes reflect evolutionary favored adaptations that, once translated to the clinics, could help improve atrophy treatment.

Stroke in pregnancy

Stroke is uncommon among young adults. However, the incidence of stroke among young women increases with pregnancy during peripartum and postpartum periods. The relative risk of suffering from haemorrhagic stroke was three times higher than ischemic stroke during these periods when compared with antenatal period. Neuroimaging should be prioritized in order to establish diagnosis and to facilitate treatment in a patient with suspected acute stroke. Prophylaxic anticoagulants should be used in high risk patients. Treatments of acute stroke in pregnant women include anti-platelet and thrombolytic agents. Further studies should be carried as there is lack of high level of evidences to formulate clear guideline for the management of stroke during pregnancy.

First Direct-Detection Constraints on eV-Scale Hidden-Photon Dark Matter with DAMIC at SNOLAB

We present direct detection constraints on the absorption of hidden-photon dark matter with particle masses in the range 1.2-30  eV c^{-2} with the DAMIC experiment at SNOLAB. Under the assumption that the local dark matter is entirely constituted of hidden photons, the sensitivity to the kinetic mixing parameter κ is competitive with constraints from solar emission, reaching a minimum value of 2.2×10^{-14} at 17  eV c^{-2}. These results are the most stringent direct detection constraints on hidden-photon dark matter in the galactic halo with masses 3-12  eV c^{-2} and the first demonstration of direct experimental sensitivity to ionization signals <12  eV from dark matter interactions.

The α-β circular scanning with large range and low noise

A circular-route scanning method called α-β circular scanning is proposed and realized using sinusoidal signals with a constant phase difference of π/2. Experiments show that the circular scanning range of α-β circular scanning is 57% greater than the rectangular scanning range of raster scanning within an effective optical field of view. Moreover, the scanning speed is improved by 7.8% over raster scanning because the whole sine signal is utilized in α-β circular scanning whereas the flyback area of the saw-tooth signal needs to be discarded in raster scanning. The maximum scanning acceleration decreases by a factor of 44, drastically decreasing the high noise, which should considerably elongate the lifetime of the galvanometers while inhibiting internal vibration. The proposed α-β circular scanning technique could be used in scanning imaging, optical tweezers and laser-beam fabrication.

Diagnostic value of recombinant Tp0821 protein in serodiagnosis for syphilis

Syphilis is a multistage sexually transmitted disease that remains a serious public health concern worldwide. The coexistence of Treponema pallidum with other closely related members of spirochaeta, such as Leptospira spp. and Borrelia burgdorferi, has complicated the serodiagnosis due to cross-reactive antigens. In this study, recombinant Tp0821 protein was expressed in Escherichia coli and purified by metal affinity chromatography. Then enzyme-linked immunosorbent assays (ELISAs) based on Tp0821 for the detection of specific antibodies were established. The relative positive rates of the IgM ELISA and the IgG ELISA were found to be 91·0 and 98·3%, respectively, when screening 578 syphilis specimens. The specificities were 94·3 and 100%, respectively, when cross-checking with serum samples obtained from 30 patients with Lyme disease, five patients with leptospirosis, and 52 uninfected controls. In addition, relative positive rates and specificities of Tp0821 for human sera were all 100% in Western blotting. When compared to the syphilis diagnostic tests commonly used in clinical settings, we found that the results of Tp0821-based ELISAs correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the chemiluminescent immunoassay (CIA). Thus, these findings identify Tp0821 as a novel serodiagnostic candidate for syphilis.

SIGNIFICANCE AND IMPACT OF THE STUDY

In this study, we expressed and purified the Treponema pallidum protein Tp0821 and developed Tp0821-based enzyme-linked immunosorbent assays (ELISAs) for the detection of specific antibodies. The serodiagnostic performance of the recombinant protein was then evaluated. When compared to the results of syphilis diagnostic tests commonly used in clinical settings, we found that the reactivities of syphilitic sera with the recombinant antigen correlated well with the results of the treponemal tests, specifically the T. pallidum particle agglutination (TP-PA) test and the chemiluminescent immunoassay (CIA). Thus, the recombinant protein shows promise as a new diagnostic antigen in the ELISAs.

A Review of Daclatasvir Drug-Drug Interactions

The treatment of hepatitis C virus (HCV) infection has been revolutionized in recent years by the development of direct-acting antiviral regimens that do not contain peginterferon (pegIFN) and/or ribavirin (RBV). While direct-acting antiviral-based regimens have been shown to be greatly superior to pegIFN/RBV-based regimens in terms of efficacy and safety, they have a greater susceptibility to drug-drug interactions (DDIs). Daclatasvir (DCV)-the benchmark pangenotypic nonstructural protein 5A inhibitor-has been shown to be efficacious and generally well tolerated in partnership with other HCV direct-acting antivirals, including sofosbuvir, asunaprevir (ASV), and ASV plus beclabuvir. DCV may be the object of a DDI via the induction or inhibition of cytochrome P450 (CYP) 3A4 and/or P-glycoprotein (P-gp) by the concomitant medication, or the precipitant of a DDI via DCV-based induction/inhibition of CYP 3A4 or inhibition of P-gp, organic anion transporting polypeptide 1B1/B3, and/or breast cancer resistance protein. This article presents an overview of the drug interaction studies conducted during the clinical development of DCV, the findings of these studies that led to the guidance on concomitant medication use and dosage along with any required DCV dose modifications, and the use of the known metabolic pathway of DCV to guide concomitant dosing where direct drug-drug studies have not been conducted. The robust characterization of the DCV clinical pharmacology program has demonstrated that DCV has few or no clinically relevant DDIs with medications with which it is likely to be co-administered, and the majority of DDIs that do occur can be predicted and easily managed.

FUNDING

Bristol-Myers Squibb.

Daclizumab high-yield process reduced the evolution of new gadolinium-enhancing lesions to T1 black holes in patients with relapsing-remitting multiple sclerosis

BACKGROUND AND PURPOSE

In the SELECT study, treatment with daclizumab high-yield process (DAC HYP) versus placebo reduced the frequency of gadolinium-enhancing (Gd(+) ) lesions in patients with relapsing-remitting multiple sclerosis (RRMS). The objective of this post hoc analysis of SELECT was to evaluate the effect of DAC HYP on the evolution of new Gd(+) lesions to T1 hypointense lesions (T1 black holes).

METHODS

SELECT was a randomized double-blind study of subcutaneous DAC HYP 150 or 300 mg or placebo every 4 weeks. Magnetic resonance imaging (MRI) scans were performed at baseline and weeks 24, 36 and 52 in all patients and monthly between weeks 4 and 20 in a subset of patients. MRI scans were evaluated for new Gd(+) lesions that evolved to T1 black holes at week 52. Data for the DAC HYP groups were pooled for analysis.

RESULTS

Daclizumab high-yield process reduced the number of new Gd(+) lesions present at week 24 (P = 0.005) or between weeks 4 and 20 (P = 0.014) that evolved into T1 black holes at week 52 versus placebo. DAC HYP treatment also reduced the percentage of patients with Gd(+) lesions evolving to T1 black holes versus placebo.

CONCLUSIONS

Treatment with DAC HYP reduced the evolution of Gd(+) lesions to T1 black holes versus placebo, suggesting that inflammatory lesions that evolved during DAC HYP treatment are less destructive than those evolving during placebo treatment.

Isolation and characterization of a chalcone isomerase gene promoter from potato cultivars

Chalcone isomerase (CHI) is a key enzyme involved in anthocyanin metabolism. Previous research on CHI has mainly focused on cDNA cloning and gene expression. In the current study, the 1425-bp potato CHI promoter (PCP) was isolated from four potato cultivars (Heijingang, Zhongshu 7, Désirée, and Favorita) using PCR and DNA sequencing. The PCP contained many cis-regulatory elements (CREs) related to anthocyanin metabolism, tissue specificity, light response, stress, and hormone induction. Of the PCP CREs identified, 19 were common to those found in the higher plants examined, based on plant CRE databases. Multiple sequence alignment showed six single nucleotide variation sites in PCP among the potato cultivars examined, resulting in changes in the number of CREs connected with tissue specificity, anthocyanin metabolism, and light response. The 665-bp PCP fragments from Favorita and 1425-bp PCP fragments from Heijingang were used to construct plant expression vectors, which may be a useful tool for biological engineering. A transient expression assay demonstrated that the two PCP fragments from Heijingang could direct the expression of a green fluorescent protein gene in onion epidermis and a β-glucuronidase gene in all potato tuber tissues with different colors, suggesting that the single nucleotide variation in the PCP did not affect its activity, and that silencing of the CHI gene in Favorita may be attributed to other regulatory factors.