High hand grip strength is a significant risk factor and a useful predictor of postoperative pancreatic fistula following pancreaticoduodenectomy.

BACKGROUND: Postoperative pancreatic fistula (POPF) is one of the most critical complications of pancreaticoduodenectomy (PD). Studies on predictive factors for POPF that can be identified preoperatively are limited. Recent reports have highlighted the association between the preoperative nutritional status, including sarcopenia, and postoperative complications. We examined preoperative risk factors for POPF after PD, focusing on nutritional indicators. METHODS: A total of 153 consecutive patients who underwent PD at our institution were enrolled in this study. Preoperative nutritional parameters, including hand grip strength (HGS) and skeletal muscle mass as components of sarcopenia, were incorporated into the analysis. POPFs were categorized according to the International Study Group of Pancreatic Fistula (ISGPF) definition as biochemical (grade A) or clinically relevant (CR-POPF; grades B and C). RESULTS: Thirty-seven of the 153 patients (24.1%) fulfilled the ISGPF definition of CR-POPF postoperatively. In the univariate analysis, the incidence of CR-POPF was associated with male sex, non-pancreatic tumor diseases, a high body mass index, a high HGS and a high skeletal muscle mass index. In the multivariate analysis, non-pancreatic tumor diseases and an HGS ≥23.0 kg were selected as independent risk factors for CR-POPF (P <0.05). CONCLUSIONS: A high HGS, a screening tool for sarcopenia, was a risk factor for CR-POPF. It can accurately serve as a useful predictor of POPF risk in patients undergoing PD. These results highlight the potential of sarcopenia to reduce the incidence of POPF and highlight the need to clarify the mechanism of POPF occurrence.

N-acetylglucosaminyltransferase-V requires a specific noncatalytic luminal domain for its activity toward glycoprotein substrates.

N-acetylglucosaminyltransferase-V (GnT-V or MGAT5) catalyzes the formation of an N-glycan ß1,6-GlcNAc branch on selective target proteins in the Golgi apparatus and is involved in cancer malignancy and autoimmune disease etiology. Several three-dimensional structures of GnT-V were recently solved, and the recognition mechanism of the oligosaccharide substrate was clarified. However, it is still unclear how GnT-V selectively acts on glycoprotein substrates. In this study, we focused on an uncharacterized domain at the N-terminal side of the luminal region (N domain) of GnT-V, which was previously identified in a crystal structure, and aimed to reveal its role in GnT-V action. Using lectin blotting and fluorescence assisted cell sorting analysis, we found that a GnT-VΔN mutant lacking the N domain showed impaired biosynthetic activity in cells, indicating that the N domain is required for efficient glycosylation. To clarify this mechanism, we measured the in vitro activity of purified GnT-VΔN toward various kinds of substrates (oligosaccharide, glycohexapeptide, and glycoprotein) using HPLC and a UDP-Glo assay. Surprisingly, GnT-VΔN showed substantially reduced activity toward the glycoprotein substrates, whereas it almost fully maintained its activity toward the oligosaccharides and the glycopeptide substrates. Finally, docking models of GnT-V with substrate glycoproteins suggested that the N domain could interact with the substrate polypeptide directly. Our findings suggest that the N domain of GnT-V plays a critical role in the recognition of glycoprotein substrates, providing new insights into the mechanism of substrate-selective biosynthesis of N-glycans.

Non-collinear generation of ultra-broadband parametric fluorescence photon pairs using chirped quasi-phase matching slab waveguides.

Many optical quantum applications rely on broadband frequency correlated photon pair sources. We previously reported a scheme for collinear emission of high-efficiency and ultra-broadband photon pairs using chirped quasi-phase matching (QPM) periodically poled stoichiometric lithium tantalate (PPSLT) ridge waveguides. However, collinearly emitted photon pairs cannot be directly adopted for applications that are based on two-photon interference, such as quantum optical coherence tomography (QOCT). In this work, we developed a chirped QPM device with a slab waveguide structure. This device was designed to produce spatially separable (photon pair non-collinear emission) parametric fluorescence photon pairs with an ultra-broadband bandwidth in an extremely efficient manner. Using a non-chirped QPM slab waveguide, we observed a photon pair spectrum with a full-width-at-half-maximum (FWHM) bandwidth of 26 nm. When using a 3% chirped QPM slab waveguide, the FWHM bandwidth of the spectrum increased to 190 nm, and the base-to-base width is 308 nm. We also confirmed a generation efficiency of 2.4×106 pairs/(µW·s) using the non-chirped device, and a efficiency of 8×105 pairs/(µW·s) using the 3% chirped device under non-collinear emission conditions after single-mode fiber coupling. This is, to the best of our knowledge, the first report of frequency correlated photon pairs generation using slab waveguide device as a source. In addition, using slab waveguides as photon pair sources, we performed two-photon interference experiments with the non-chirped device and obtained a Hong-Ou-Mandel (HOM) dip with a FWHM of 7.7 µm and visibility of 98%. When using the 3% chirped device as photon pair source, the HOM measurement gave a 2 µm FWHM dip and 74% visibility.

Regulating Antifreeze Activity through Water: Latent Functions of the Sugars of Antifreeze Glycoprotein Revealed by Total Chemical Synthesis.

Antifreeze glycoprotein (AFGP), which inhibits the freezing of water, is highly O-glycosylated with a disaccharide, d-Galß1-3-d-GalNAcα (GalGalNAc). To elucidate the function of the sugar residues for antifreeze activity at the molecular level, we conducted a total chemical synthesis of partially sugar deleted AFGP derivatives, and unnatural forms of AFGPs incorporating glucose (Glc)-type sugars instead of galactose (Gal)-type sugars. These elaborated AFGP derivatives demonstrated that the stereochemistry of each sugar residue on AFGPs precisely correlates with the antifreeze activity. A hydrogen-deuterium exchange experiment using synthetic AFGPs revealed a different dynamic behavior of water around sugar residues depending on the sugar structures. These results indicate that sugar residues on AFGP form a unique dynamic water phase that disturbs the absorbance of water molecules onto the ice surface, thereby inhibiting freezing.

Rapid Chemical Synthesis of Serine Protease Inhibitor Kazal-type 13 (SPINK13) Glycoform by a Combined Method with Glycan Insertion Strategy and Fast-Flow Fmoc SPPS.

Serine protease inhibitor Kazal type 13 (SPINK13) is a secreted protein that has been recently studied as a therapeutic drug and an interesting biomarker for cancer cells. Although SPINK13 has a consensus sequence (Pro-Asn-Val-Thr) for N-glycosylation, the existence of N-glycosylation and its functions are still unclear. In addition to this, the preparation of glycosylated SPINK 13 has not been examined by both the cell expression method and chemical synthesis. Herein we report the chemical synthesis of the scarce N-glycosylated form of SPINK13 by a rapid synthetic method combined with the chemical glycan insertion strategy and a fast-flow SPPS method. Glycosylated asparagine thioacid was designed to chemoselectively be inserted between two peptide segments where is the sterically bulky Pro-Asn(N-glycan)-Val junction by two coupling reactions which consist of diacyl disulfide coupling (DDC) and thioacid capture ligation (TCL). This insertion strategy successfully afforded the full-length polypeptide of SPINK13 within two steps from glycosylated asparagine thioacid. Because the two peptides used for this synthesis were prepared by a fast-flow SPPS, the total synthetic time of glycoprotein was considerably shortened. This synthetic concept enables us to repetitively synthesize a target glycoprotein easily. Folding experiments afforded well-folded structure confirmed by CD and disulfide bond map. Invasion assays of glycosylated SPINK13 and non-glycosylated SPINK13 with pancreatic cancer cells showed that non-glycosylated SPINK-13 was more potent than that of glycosylated SPINK13.

Quantum Fourier-transform infrared spectroscopy in the fingerprint region.

Infrared quantum absorption spectroscopy is one of the quantum sensing techniques, by which the infrared optical properties of a sample can be estimated through visible or near infrared photon detection without need for infrared optical source or detector, which has been an obstacle for higher sensitivity and spectrometer miniaturization. However, experimental demonstrations have been limited to wavelengths shorter than 5 µm or in the terahertz region, and have not been realized in the so-called fingerprint region of 1500-500 cm-1 (6.6 to 20 µm), which is commonly used to identify chemical compounds or molecules. Here we report the experimental demonstration of quantum Fourier-transform infrared (QFTIR) spectroscopy in the fingerprint region, by which both absorption and phase spectra (complex spectra) can be obtained from Fourier transformed quantum interferograms obtained with a single pixel visible-light detector. As demonstrations, we obtained the transmittance spectrum of a silicon wafer at around 10 µm (1000 cm-1) and complex transmittance spectrum of a synthetic fluoropolymer sheet, polytetrafluoroethylene, in the wavelength range of 8 to 10.5 µm (1250 to 950 cm-1), where absorption due to stretching modes of C-F bonds is clearly observed. These results open the way for new forms of spectroscopic devices based on quantum technologies.

High-depth-resolution imaging of dispersive samples using quantum optical coherence tomography.

Quantum optical coherence tomography (QOCT) is a promising approach to overcome the degradation of the resolution in optical coherence tomography (OCT) due to dispersion. Here, we report on an experimental demonstration of QOCT imaging in the high-resolution regime. We achieved a depth resolution of 2.5 µm, which is the highest value for QOCT imaging, to the best of our knowledge. We show that the QOCT image of a dispersive material remains clear whereas the OCT image is drastically degraded.

Design and Synthesis of Glycosylated Cholera Toxin B Subunit as a Tracer of Glycoprotein Trafficking in Organelles of Living Cells.

Glycosylation of proteins is known to be essential for changing biological activity and stability of glycoproteins on the cell surfaces and in body fluids. Delivering of homogeneous glycoproteins into the endoplasmic reticulum (ER) and the Golgi apparatus would enable us to investigate the function of asparagine-linked (N-) glycans in the organelles. In this work, we designed and synthesized an intentionally glycosylated cholera toxin B-subunit (CTB) to be transported to the organelles of mammalian cells. The heptasaccharide, the intermediate structure of various complex-type N-glycans, was introduced to the CTB. The synthesized monomeric glycosyl-CTB successfully entered mammalian cells and was transported to the Golgi and the ER, suggesting the potential use of synthetic CTB to deliver and investigate the functions of homogeneous N-glycans in specific organelles of living cells.

Semisynthesis of a Homogeneous Glycoprotein Using Chemical Transformation of Peptides to Thioester Surrogates.

Semisynthesis using recombinant polypeptides as building blocks is a powerful approach for the preparation of proteins with a variety of modifications such as glycosylation. The activation of the C terminus of recombinant peptides is a key step for coupling peptide building blocks and preparing a full-length polypeptide of a target protein. This article reports two chemical approaches for transformation of the C terminus of recombinant polypeptides to thioester surrogates. The first approach relies on efficient substitution of the C-terminal Cys residue with bis(2-sulfanylethyl)amine (SEA) to yield peptide-thioester surrogates. The second approach employs a native tripeptide, cysteinyl-glycyl-cysteine (CGC), to yield peptide-thioesters via a process mediated by a thioester surrogate. Both chemical transformation methods employ native peptide sequences and were thereby successfully applied to recombinant polypeptides. As a consequence, we succeeded in the semisynthesis of a glycosylated form of inducible T cell costimulator (ICOS) for the first time.

Optimizing the Semisynthesis towards glycosylated interferon-ß-polypeptide by utilizing bacterial protein expression and chemical modification.

The synthesis of a sufficient amount of homogeneous glycoprotein is of great interest because natural glycoproteins show considerable heterogeneity in oligosaccharide structures, making the studies on glycan structure-function relationship difficult. Herein, we report optimized methods that can accelerate the semisynthesis of homogeneous glycoproteins based on recombinant expression and chemical conversion. Peptide thioesters and peptides with Cys residues at their N-terminals are necessary intermediates to perform native chemical ligation. We successfully performed thioesterification for a peptide prepared in E. coli via Cys-cyanylation at its C-terminal followed by hydrazinolysis and acidic thiolysis. These optimized conditions could tolerate an acid labile Thz protected Cys at the N-terminal of a peptide-hydrazide and specific cyanylation of the C-terminal Cys to yield a peptide thioester. To reduce the amount of precious oligosaccharide that is required in the conventional SPPS method, an improved liquid phase glycopeptide coupling was also optimized in a good yield (46% over four steps). Lastly, chemoselective protection of the internal cysteines and activation of the N-terminal cysteine were optimized toward a long peptide prepared in E. coli. By using these strategies, a full-length interferon-ß glycosyl polypeptide as a model was successfully obtained.

[Two Cases of Elderly Patients with Giant Intrahepatic Cholangiocarcinoma Treated with Multidisciplinary Therapy including Ablation Therapy].

Case 1 consisted of an 86-year-old male diagnosed with intrahepatic cholangiocarcinoma(ICC), approximately 11 cm in diameter, at segment S7/8 of the liver. A total of 4 percutaneous radiofrequency ablations(PRFA)and 3 hepatic arterial infusion chemotherapies(HAIC)of 5-FU were performed. He died after developing lung metastases 27 months after the initial treatment. Case 2 was an 85-year-old female diagnosed with ICC, 8 cm in diameter, at the posterior segment of the liver, with lymph node metastasis. She underwent HAIC of 5-FU and S-1 as well as gemcitabine-based systemic chemotherapy. The main tumor developed 10 months after the initial treatment, and PRFAs were subsequently performed twice for the main lesion. Although the tumor markers gradually decreased, she died of jaundice 33 months after the initial treatment. As one of the multidisciplinary therapies for the giant ICC, ablation therapy may be safe and effective in elderly patients.

[Clinical Study of Peritoneovenous Shunt for Patients with Refractory Ascites Accompanied with Hepatocellular Carcinoma].

BACKGROUND: Hepatic ascites may cause a variety of symptoms and may progress deterioration of quality of life. Peritoneovenous shunt(PV shunt)is technically feasible and useful for the treating of refractory ascites, but sometimes it can be associated with fatal complications. This retrospective study aimed to investigate the effect of PV shunt for patients with refractory ascites, including hepatocellular carcinoma(HCC)patients. SUBJECTS: Between January 2010 and December 2021, we retrospectively analyzed 54 consecutive patients(including 35 HCC patients)with refractory ascites who underwent PV shunt at our institute. RESULTS: Body weight loss after surgery was observed in 39 of the 54 cases, and eGFR improved in 34 cases. There were 17(31.5%)in-hospital deaths. Cases with present of portal vein tumor thrombus, Child-Pugh classification C, ALBI score≥-1.12, or serum total bilirubin≥1.7 mg/dL were significantly higher in hospital-death group than in the discharged from the hospital group. CONCLUSIONS: PV shunt for HCC patients with refractory ascites may be effective for improvement of renal function and symptoms. However, indications for PV shunt should be carefully considered for high-risk patients with adequate preoperative evaluation.

[A Case of Long-Term Survival with S-1/Cisplatin for Liver Hilum Lymph Node Metastasis of Anal Canal Squamous Cell Carcinoma after Chemoradiotherapy].

A 70-year-old woman was admitted to a local hospital because of anal pain during defecation. Anoscopy revealed an anal mass lesion, and the patient was referred to our hospital. Colonoscopy revealed an anal canal tumor with ulceration, and biopsy showed squamous cell carcinoma. The patient was treated with chemoradiotherapy(chemotherapy with capecitabine plus mitomycin C and 54 Gy radiation in the anal region)and achieved complete response. However, metastatic recurrence was detected in a lymph node in the hepatic hilar region. We administered an S-1/CDDP combination chemotherapy (5 courses). For 3 years and 5 months since the initial treatment, the patient survived with no signs of recurrence. We report a rare case of long-term survival with S-1/CDDP for distant metastasis of anal canal squamous cell carcinoma after chemoradiotherapy.

[Clinical Efficacy of Recombinant Human Thrombomodulin for Surgical Patients with Disseminated Intravascular Coagulation Associated with Oncologic Emergency].

AIM: We evaluated the clinical efficacy of recombinant human thrombomodulin(rTM)for surgical patients with disseminated intravascular coagulation syndrome(DIC)associated with an oncologic emergency(OE). SUBJECTS AND METHODS: Thirteen patients who underwent surgery for OE complicated with DIC and were treated with rTM in our institution were evaluated. We retrospectively analyzed the clinical changes of parameters in white blood cell count(WBC), platelet count, CRP, PT-INR and DIC scores after the rTM treatment. RESULTS: The average length of the days using rTM was 4.7 for 12 patients, excluding one who died within 30 days after surgery. Nine of 12 patients(75%)had DIC scores of less than 3 after the rTM treatment. WBC tended to decrease after the rTM treatment, without statistical difference. However, CRP, platelet count, PT-INR and DIC scores were significantly improved after the rTM treatment(p<0.05). CONCLUSIONS: rTM may be useful in the treatment of DIC for surgical OE patients.

[A Rapid Clinical Course of Pulmonary Embolism Associated with Gallbladder Mucinous Carcinoma].

A 51-year-old woman with edema of the lower extremities and exertional dyspnea was admitted to our hospital. Enhanced CT revealed thrombi of the pulmonary artery and a gallbladder tumor. After anticoagulation therapy was started on her, anemia and jaundice progressed; thus, endoscopic retrograde cholangiopancreatography(ERCP)was performed on suspicion of bleeding from a gallbladder tumor. We performed cholecystectomy in emergency to control the anemia due to hemorrhage. Oxygenation suddenly worsened intraoperatively, maintaining her blood pressure became difficult, and the patient decompensated. The histopathological diagnosis was gallbladder mucinous carcinoma with severe lymphatic invasion. Although an autopsy was not performed, pulmonary artery embolism derived from a tumor embolus was the suspected cause of the sudden change of the clinical course.

Glycoprotein Semisynthesis by Chemical Insertion of Glycosyl Asparagine Using a Bifunctional Thioacid-Mediated Strategy.

Glycosylation is a major modification of secreted and cell surface proteins, and the resultant glycans show considerable heterogeneity in their structures. To understand the biological processes arising from each glycoform, the preparation of homogeneous glycoproteins is essential for extensive biological experiments. To establish a more robust and rapid synthetic route for the synthesis of homogeneous glycoproteins, we studied several key reactions based on amino thioacids. We found that diacyl disulfide coupling (DDC) formed with glycosyl asparagine thioacid and peptide thioacid yielded glycopeptides. This efficient coupling reaction enabled us to develop a new glycoprotein synthesis method, such as the bifunctional thioacid-mediated strategy, which can couple two peptides with the N- and C-termini of glycosyl asparagine thioacid. Previous glycoprotein synthesis methods required valuable glycosyl asparagine in the early stage and subsequent multiple glycoprotein synthesis routes, whereas the developed concept can generate glycoproteins within a few steps from peptide and glycosyl asparagine thioacid. Herein, we report the characterization of the DDC of amino thioacids and the efficient ability of glycosyl asparagine thioacid to be used for robust glycoprotein semisynthesis.

Efficient generation of ultra-broadband parametric fluorescence using chirped quasi-phase-matched waveguide devices.

We present a highly efficient photon pair source using chirped quasi-phase-matched (QPM) devices with a ridge waveguide structure. We developed QPM waveguide devices with chirp rates of 3% and 6.7%. Spectrum measurements reveal that the generated photons have bandwidths of 229 nm and 325 nm in full width at half maximum (FWHM), alternatively, 418 nm and 428 nm in base-to-base width for the 3% and 6.7% chirped devices, respectively, which are much broader than the bandwidth of 16 nm in FWHM observed with a non-chirp device. We also evaluate the generation efficiency of photon pairs from coincidence measurements using two superconducting single photon detectors (SSPDs). The estimated generation efficiencies of photon pairs were 2.7 × 106 pairs/s·µW and 1.2 × 106 pairs/s·µW for the 3% and 6.7% chirped devices, respectively, which are comparable to the generation efficiency for the non-chirp device of 2.7 × 106 pairs/s·µW. We also measured the frequency correlation of the photon pairs generated from the 6.7% chirped device. The experimental results clearly show the frequency correlation of the generated broadband photon pairs.

Frequency correlated photon generation at telecom band using silicon nitride ring cavities.

Frequency entangled photon sources are in high demand in a variety of optical quantum technologies, including quantum key distribution, cluster state quantum computation and quantum metrology. In the recent decade, chip-scale entangled photon sources have been developed using silicon platforms, offering robustness, large scalability and CMOS technology compatibility. Here, we report the generation of frequency correlated photon pairs using a 150-GHz silicon nitride ring cavity. First, the device is characterized for studying the phase matching condition during spontaneous four-wave mixing. Next, we evaluate the joint spectrum intensity of the generated photons and confirm the photon pair generation in a total of 42 correlated frequency mode pairs, corresponding to a bandwidth of 51.25 nm. Finally, the experimental results are analyzed and the joint spectral intensity is quantified in terms of the phase matching condition.

Chemical Synthesis of an Erythropoietin Glycoform Having a Triantennary N-Glycan: Significant Change of Biological Activity of Glycoprotein by Addition of a Small Molecular Weight Trisaccharide.

The glycosylation of proteins contributes to the modulation of the structure and biological activity of glycoproteins. Asparagine-linked glycans (N-glycans) of glycoproteins naturally exhibit diverse antennary patterns, such as bi-, tri-, and tetra-antennary forms. However, there are no chemical or biological methods to obtain homogeneous glycoproteins via the intentional alteration of the antennary form of N-glycans. Thus, the functions of the individual antennary form of N-glycan at a molecular level remain unclear. Herein, we report the chemical synthesis of an erythropoietin (EPO) glycoform having a triantennary sialylglycan at position 83, as well as two biantennary sialylglycans at both positions 24 and 38. We demonstrated efficient liquid-phase condensation reactions to prepare a sialylglycopeptide having a triantennary N-glycan prepared by the addition of a Neu5Ac-α-2,6-Gal-ß-1,4-GlcNAc element to the biantennary glycan under semisynthetic conditions. The molecular weight of the newly added antennary element was ∼3% of the EPO glycoform, and the introduced position was the most distant from the bioactive protein. However, in vivo assays using mice revealed that the additional antennary element at position 83 dramatically increased the hematopoietic activity compared to a commercially available native EPO. These unprecedented data clearly indicate that the antennary pattern of N-glycans inherently plays a critical role in the modulation of protein functions.

Total Chemical Synthesis of a Nonfibrillating Human Glycoinsulin.

Glycosylation is an accepted strategy to improve the therapeutic value of peptide and protein drugs. Insulin and its analogues are life-saving drugs for all type I and 30% of type II diabetic patients. However, they can readily form fibrils which is a significant problem especially for their use in insulin pumps. Because of the solubilizing and hydration effects of sugars, it was thought that glycosylation of insulin could inhibit fibril formation and lead to a more stable formulation. Since enzymatic glycosylation results in heterogeneous products, we developed a novel chemical strategy to produce a homogeneous glycoinsulin (disialo-glycoinsulin) in excellent yield (∼60%). It showed a near-native binding affinity for insulin receptors A and B in vitro and high glucose-lowering effects in vivo, irrespective of the route of administration (s.c. vs i.p.). The glycoinsulin retained insulin-like helical structure and exhibited improved stability in human serum. Importantly, our disialo-glycoinsulin analogue does not form fibrils at both high concentration and temperature. Therefore, it is an excellent candidate for clinical use in insulin pumps.