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71.
72.
Acute funisitis is characterized by the infiltration of fetal neutrophils from the umbilical vessels into Wharton’s jelly and presents as fetal inflammation. However, no reports about its prenatal diagnosis using ultrasonography have been published. We encountered one case of oligohydramnios at 26 weeks and another case of threatened premature delivery at 27 weeks of gestation with ultrasonographic findings of non-uniform thickening of Wharton’s jelly, a heterogeneous internal echo, and a high echoic line of the umbilical vessel wall. Acute funisitis was diagnosed, and the postpartum histopathological examination revealed severe funisitis in both cases. To our knowledge, this is the first case report of prenatal diagnosis of funisitis determined using ultrasonography. When we find such ultrasonographic features under the circumstances of intrauterine infection, severe funisitis should be included in the differential diagnosis.  相似文献   
73.

Introduction

G protein-coupled receptor 119 (GPR119) is a promising target for the treatment of type 2 diabetes mellitus (T2DM), as both insulin and glucagon-like peptide-1 secretion can be promoted with a single drug. We compared the efficacy and safety of the GPR119 agonist DS-8500a with placebo and sitagliptin 50 mg in Japanese patients with T2DM.

Methods

This randomized, double-blind, parallel-group comparison study was conducted in Japan (trial registration NCT02628392, JapicCTI-153068). Eligible patients aged ≥ 20 years with T2DM and hemoglobin A1c (HbA1c) ≥ 7.0% and < 10.0% were randomized to receive placebo, DS-8500a (25, 50, or 75 mg), or sitagliptin 50 mg once daily for 12 weeks. The primary efficacy endpoint was change in HbA1c from baseline to week 12. Secondary endpoints included change in fasting plasma glucose (FPG), glucose AUC0–3h during a meal tolerance test, 2-hour postprandial glucose (2hr-PPG), and changes in lipid parameters (total, low-density lipoprotein (LDL-) and high-density lipoprotein (HDL-) cholesterol, and triglycerides) at week 12. Safety endpoints included adverse events, hypoglycemia, and clinical/laboratory variables.

Results

DS-8500a demonstrated dose-dependent HbA1c lowering compared with placebo at week 12: change from baseline ? 0.23% (p = 0.0173), ? 0.37% (p = 0.0001), and ? 0.44% (p < 0.0001) in the 25-mg, 50-mg, and 75-mg groups, respectively. At 50- and 75-mg doses, DS-8500a significantly lowered FPG, glucose AUC0–3h, and 2hr-PPG compared with placebo. The glucose-lowering effect was maintained up to 12 weeks. DS-8500a did not lower any of the above parameters to a greater extent than sitagliptin. Compared with placebo and sitagliptin, DS-8500a 50 and 75 mg significantly reduced total cholesterol, LDL-cholesterol, and triglycerides, and significantly increased HDL-cholesterol. All DS-8500a doses were well tolerated. Two cases of clinically relevant drug-related hypoglycemia occurred in the DS-8500a 50-mg group.

Conclusion

DS-8500a was well tolerated and demonstrated significant glucose-lowering effects and favorable changes in lipid profiles up to 12 weeks in Japanese patients with T2DM.

Funding

Daiichi Sankyo Co. Ltd.
  相似文献   
74.
Objective A survival benefit was demonstrated for ramucirumab (RAM) in patients with unresectable hepatocellular carcinoma (uHCC) and α-fetoprotein (AFP) concentrations ≥400 ng/mL who had previously received sorafenib (SOR). However, it is unclear whether RAM has a similar efficacy in patients with uHCC that progresses after lenvatinib (LEN) treatment. This study aimed to evaluate the early anti-tumor response to RAM as a second-line treatment for advanced uHCC after LEN treatment. Methods We retrospectively assessed the efficacy and safety of RAM at 6 weeks after initiation. The therapeutic effects were evaluated according to the Response Evaluation Criteria in Solid Tumors version 1.1. Patients We evaluated 7 patients with uHCC who received RAM as a second- or third-line treatment after LEN failure. Results The disease control rate (DCR) was 28.6% (2 of 7 patients). After the initiation of RAM, a rapid disease progression resulted in 1 patient death after 19 days. The median progression-free survival (PFS) was 41 days. There were no grade 3 or 4 treatment-related adverse events. At 6 weeks, there was no deterioration in the modified albumin-bilirubin (mALBI) grade. In patients with an imaging response of stable disease (SD), the rate of AFP production decreased from the baseline. Conclusion RAM may have a therapeutic potential for the suppression of uHCC progression in patients previously treated with LEN, as well as for maintaining the liver function during treatment. Evaluating the AFP trends may therefore be useful for predicting RAM effectiveness.  相似文献   
75.
We herein report a case of aortitis induced by granulocyte colony-stimulating factor (G-CSF) that coincided with lung injury, splenomegaly, and cutaneous manifestations during treatment for recurrent extraosseous mucinous chondrosarcoma. Computed tomography revealed large-vessel vasculitis, splenomegaly, and pulmonary interstitial changes. Treatment with prednisolone was successful. Because sarcoma is a rare disease, this case is valuable for showing clinicians that G-CSF preparations could cause aortitis regardless of the patient''s underlying diseases or therapeutic pharmacological backgrounds.  相似文献   
76.
Purpose

Sleep-disordered breathing is recognized as a comorbidity in patients with idiopathic pulmonary fibrosis (IPF). Among them, nocturnal hypoxemia has been reported to be associated with poor prognosis and disease progression. We developed a diagnostic algorithm to classify nocturnal desaturation from percutaneous oxygen saturation (SpO2) waveform patterns: sustained pattern, periodic pattern, and intermittent pattern. We then investigated the prevalence of nocturnal desaturation and the association between the waveform patterns of nocturnal desaturation and clinical findings of patients with IPF.

Methods

We prospectively enrolled patients with IPF from seven general hospitals between April 2017 and March 2020 and measured nocturnal SpO2 and nasal airflow by using a home sleep apnea test. An algorithm was used to classify the types of nocturnal desaturation. We evaluated the association between sleep or clinical parameters and each waveform pattern of nocturnal desaturation.

Results

Among 60 patients (47 men) who met the eligibility criteria, there were 3 cases with the sustained pattern, 49 cases with the periodic pattern, and 41 cases with the intermittent pattern. Lowest SpO2 during sleep and total sleep time spent with SpO2?<?90% were associated with the sustained pattern, and apnea–hypopnea index was associated with the intermittent pattern.

Conclusion

We demonstrated the prevalence of each waveform and association between each waveform and sleep parameters in patients with IPF. This classification algorithm may be useful to predict the degree of hypoxemia or the complication of obstructive sleep apnea.

  相似文献   
77.
78.
Herein, we report the successful performance of a laparoscopy-assisted spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein for a patient with pancreatic cystadenoma, as a minimally invasive procedure with the preservation of function. The laparoscopy-assisted distal pancreatectomy procedure involved detaching the spleen and the distal pancreas from the retroperitoneum by a hand-assisted procedure, removing them from the peritoneal cavity through a small incision, and detaching the distal pancreas by ligating and transecting the short gastric artery and vein and the branches of the splenic artery and vein, while the spleen and main splenic artery and vein were preserved under direct view. The pancreatic parenchyma was transected with a stapling device (TL-30), and continuous suturing was added to the resected margin. The patient’s postoperative course was uneventful; the patient started to eat and walk on postoperative day 2 and was discharged on day 8. It is considered that the combination of hand-assisted and laparoscopy-assisted distal pancreatectomy, with conservation of the splenic artery and vein, is a minimally invasive and clinically useful technique for treating tumors of cystic disease of the pancreas with low-grade malignant potential, or benign solitary neuroendocrine tumors.  相似文献   
79.
Background We have reported that percutaneous radiofrequency ablation (RFA) with balloon occlusion of the hepatic artery (balloon-occluded RFA), using an expandable electrode, increases the coagulation area. In this study, we investigated the efficacy of balloon-occluded RFA and balloon-microcatheter-occluded RFA, using a cool RF single electrode.Methods We studies 41 patients with 47 hepatocellular carcinoma (HCC) lesions. We treated 28 patients (32 nodules) with balloon-occluded RFA, 5 patients (6 nodules) with balloon-microcatheter-occluded RFA, and 8 patients (9 nodules) with standard RFA. Initial therapeutic efficacy was evaluated with dynamic computed tomography performed 1 week after one session of treatment.Results One session of treatment was done for 20 nodules (62.5%) in the balloon-occluded RFA group and for 4 nodules (66.7%) in the balloon-microcatheter-occluded RFA group. We compared the coagulation diameter for balloon-occluded RFA (7 nodules), balloon-microcatheter-occluded RFA (6 nodules), and standard RFA (9 nodules) after one application cycle (12min). The greatest dimension of the area coagulated by balloon-occluded RFA was significantly larger (greatest long-axis dimension, 47.6 ± 7.8mm; greatest short-axis dimension, 33.4 ± 7.5mm) than that coagulated by standard RFA (greatest long-axis dimension, 35.3 ± 4.7mm; greatest short-axis dimension, 25.9 ± 3.7mm; P = 0.002 for greatest long-axis dimension; P = 0.041 for greatest short-axis dimension). However, there was significant difference only in the greatest short-axis dimension of the area coagulated comparing balloon-microcatheter-occluded RFA and standard RFA.Conclusions We consider balloon-occluded RFA using a cool RF electrode to be superior to standard RFA for the treatment of HCC, especially when larger coagulation volumes are required.  相似文献   
80.
Ligand-gated ion channels are partially activated by their ligands, resulting in currents lower than the currents evoked by the physiological full agonists. In the case of P2X purinergic receptors, a cation-selective pore in the transmembrane region expands upon ATP binding to the extracellular ATP-binding site, and the currents evoked by α,β-methylene ATP are lower than the currents evoked by ATP. However, the mechanism underlying the partial activation of the P2X receptors is unknown although the crystal structures of zebrafish P2X4 receptor in the apo and ATP-bound states are available. Here, we observed the NMR signals from M339 and M351, which were introduced in the transmembrane region, and the endogenous alanine and methionine residues of the zebrafish P2X4 purinergic receptor in the apo, ATP-bound, and α,β-methylene ATP-bound states. Our NMR analyses revealed that, in the α,β-methylene ATP-bound state, M339, M351, and the residues that connect the ATP-binding site and the transmembrane region, M325 and A330, exist in conformational equilibrium between closed and open conformations, with slower exchange rates than the chemical shift difference (<100 s−1), suggesting that the small population of the open conformation causes the partial activation in this state. Our NMR analyses also revealed that the transmembrane region adopts the open conformation in the state bound to the inhibitor trinitrophenyl-ATP, and thus the antagonism is due to the closure of ion pathways, except for the pore in the transmembrane region: i.e., the lateral cation access in the extracellular region.In chemical neurotransmission, various neurotransmitters bind to ligand-gated ion channels expressed in the plasma membrane of postsynaptic cells, such as the NMDA, AMPA, and P2X receptors, leading to changes in membrane potential and the concentration of intracellular ions. Each ligand for a ligand-gated ion channel has a distinct ability to evoke currents (1), and the ligands are classified according to the evoked current level: such as, full agonists, partial agonists, and antagonists. Partial agonists of ligand-gated ion channels reportedly offer clinical advantages over antagonists and full agonists in antidepressant and smoking-cessation treatment (2, 3).Two mechanisms have been proposed for the partial activation of the ligand-gated ion channels: the equilibrium between the open and closed conformations and the distinct conformation of the partial agonist-bound states from the closed and open conformations (4, 5). In the crystal structures of the extracellular region of the AMPA receptor, in which the distances between the two extracellular domains are changed upon agonist binding, the interdomain distances in the partial agonist-bound states correlated with the conductance level, suggesting that the AMPA receptor adopts specific intermediately permeable conformations (4, 6).The P2X receptors are a family of cation channels gated by extracellular ATP (1, 79) and are involved in many physiological and pathophysiological processes (1012). Seven subtypes of the P2X receptors have been identified in mammals (13), and they share ∼40% sequence identity. The P2X4 receptor is involved in the pathogenesis of chronic neuropathic, inflammatory pain and the endothelial cell-mediated control of vascular tone (11, 14, 15). Compared with ATP, α,β-methylene ATP (α,β-meATP), in which the oxygen atom linking the α- and β-phosphorous atoms of ATP is replaced by a methylene group (Fig. S1A), reportedly induces a lower maximum current in cells expressing the mouse, rat, and human P2X4 receptors and other P2X receptors (16, 17).Open in a separate windowFig. S1.Characterization of the P2X4 receptor. (A) Chemical structures of ATP and α,β-meATP. (B and C) TEVC recordings of ATP- and α,β-meATP-evoked currents from rat P2X4 receptor expressed in Xenopus oocytes, respectively. In B, the currents were evoked twice by ATP (30 μM, 1 min, black bar). In C, the currents were firstly evoked by ATP (30 μM, 1 min, black bar) and subsequently by α,β-meATP (300 μM, 1 min, black bar). (D) TEVC recording of the ATP-evoked current (30 μM, 30 s, black bar) from the N-terminally EGFP-tagged ΔzfP2X4–A′ construct expressed in Xenopus oocytes. (E) Size exclusion chromatogram of purified EGFP-tagged ΔzfP2X4–A′ in rHDLs. Elution volumes corresponding to 17.0, 12.2, 10.4, and 7.1 nm Stokes diameters were determined by thyroglobulin, ferritin, catalase, and BSA, respectively. V0 and 1CV are void volume and single column volume, respectively. (F) SDS/PAGE analyses of purified ΔzfP2X4–A′ embedded in rHDLs. The samples were analyzed by 12% SDS/PAGE with Coomassie Brilliant Blue staining. (G) Measurement of [3H]ATP saturation binding to the purified ΔzfP2X4–A′ in rHDLs. (H and I) Estimation of the effects of deuteration based on the crystal structures of zfP2X4 (PDB ID code 4DW1) and the deuteration incorporation rates. The plots on the Left (without deuteration) and the Right (with deuteration) are the sums of the inverse sixth power of the distances between pseudoatoms centered on the methyl hydrogens of M108, M249, M268, or M325 and each hydrogen atom in the crystal structure of zfP2X4 (sums of the r−6) and the sums of the r−6 multiplied by [1 − (deuterium incorporation rates)] of each hydrogen atom, respectively. The graphs in H and I were calculated from the crystal structure in the apo state (PDB ID code 4DW0) and that in the ATP-bound state (PDB ID code 4DW1), respectively. Sums of the r−6 of each methionine methyl group and Hαβγ of the intraresidue methionine (green), Hαβγ of the interresidue methionine (light green), Hαβ of tyrosine (light violet), Hδεζη of tryptophan (orange), Hαβδεζ of phenylalanine (pink), Hαβγ of valine (blue), Hαβγδ of leucine (light blue), Hαβγδ of isoleucine (cyan), Hαβγ of threonine (light cyan), Hαβ of alanine (red), Hαβγδ of arginine (dark blue), Hα of glycine (dark green), and Hαβ of serine (magenta) residues, and the other hydrogens connected to carbon atoms (other unexchangeable hydrogens, light gray) are shown with colors. Hydrogen atoms connected to nitrogen, oxygen, or sulfur atoms were not considered in these calculations because these hydrogens should be exchanged with deuterium in D2O. The deuterium incorporation rates of the hydrogen atoms within each methionine residue (intraresidue) and the deuterium incorporation rates of other methionine residues (interresidue) were set to 98% and 85%, respectively, because the methionine residues would be derived from 85% of [α-, β-, γ-98% 2H-, methyl-13C]-methionine and 15% of nonlabeled methionine in the medium.The crystal structures of zebrafish P2X4 receptor (zfP2X4) (18, 19), together with mutational analyses (2026), provided the structural basis for the channel opening of P2X receptors upon ATP binding. In the crystal structures, zfP2X4 forms a homotrimer (27, 28), in which the transmembrane region of each subunit is composed of two helices (19). In the crystal structure of zfP2X4 in the ATP-bound state, three ATP molecules are bound to the intersubunit nucleotide binding pockets. In addition, the region that connects the ATP-binding site and the transmembrane region, which is referred to as the “lower body” (Fig. 1 A and B), is expanded by ∼10 Å in the ATP-bound state, and a pore is formed in the transmembrane region, which is proposed to expand by the iris-like movement of the transmembrane helices (18). However, the mechanism underlying the partial activation of P2X receptors is unknown because the structures of the P2X receptors have not been examined in the partial agonist-bound states.Open in a separate windowFig. 1.NMR resonances from the endogenous methionine residues of zfP2X4 in rHDL. (A and B) Distribution of the methionine residues in the ΔzfP2X4–A′. One subunit from the crystal structure of zfP2X4 in the apo form (A) (PDB ID code 4DW0) and one from the ATP-bound form (B) (PDB ID code 4DW1) are shown in ribbons. The lower body and the right flipper are yellow. The A330 residues, the methionine residues, and the residues in which methionine mutations were introduced, L339 and L351, are depicted by green sticks. ATP is depicted by red sticks. Dummy atoms generated by Orientations of Proteins in Membranes (OPM), which represent membrane boundary planes, are gray. (C) Overlaid 1H-13C HMQC spectra of [2H-11AA, α, β-2H, methyl-13C-Met]ΔzfP2X4-A′, embedded in rHDLs, in the apo state (black) and the ATP-bound state (red). The regions with resonances from methionine residues are shown, and the assigned resonances are indicated. The centers of the resonances are indicated with dots. Cross-sections at lines through the centers of each resonance in the ATP-bound state and the cross-sections of the spectra using [α, β-2H, methyl-13C-Met]ΔzfP2X4-A′ are shown on the top of the overlaid spectra. The intensities of the cross-sections were normalized by the concentration of ΔzfP2X4-A′ and the conditions of the NMR measurements.The P2X4 receptor used in the previous crystallographic studies was solubilized by detergents, which are widely used for structural investigations of membrane proteins, but the P2X4 receptor is embedded in lipid bilayers under physiological conditions. It was recently reported that reconstituted high-density lipoproteins (rHDLs), which are also known as nanodiscs (29), can accommodate membrane proteins within a 10-nm-diameter disk-shaped lipid bilayer (30). The rHDLs reportedly provide a lipid environment with more native-like properties, compared with liposomes, in terms of the lateral pressure and curvature profiles because detergent micelles have strong curvature and different lateral pressure profiles from lipid membranes (31). Our NMR analyses of a G protein-coupled receptor (GPCR) and an ion channel in rHDL lipid bilayers revealed that the population and the exchange rates of the conformational equilibrium determine their signal transduction and ion transport activities (3234) and that the population of the active conformation of the GPCR in rHDLs correlated better with the signaling levels than that in detergent micelles (32). Therefore, NMR investigations of membrane proteins in the lipid bilayer environments of rHDLs are necessary for accurate measurements of the exchange rates and the populations in conformational equilibrium.Here, we used NMR to observe the conformational equilibrium of the alanine and methionine residues of zfP2X4 bound to α,β-meATP in rHDLs. Based on the conformational equilibrium, we discuss the mechanism underlying the partial activation of P2X receptors.  相似文献   
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