Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Nature and treatment outcomes of bleeding post-bulbar duodenal ulcers

BACKGROUND

Although post-bulbar duodenal ulcers (PBDUs) could become a source of upper gastrointestinal bleeding, the whole picture of the disease is unknown. We compared the characteristic features and treatment outcomes after endoscopic hemostasis between PBDUs and bulbar duodenal ulcers (BDUs).

METHODS

Data on duodenal ulcers with evidence of endoscopically-active bleeding were extracted from the data that were retrospectively collected from 12 institutes in Japan between 2011 and 2018. Rebleeding and in-hospital mortality were compared between patients with PBDUs and those with BDUs by logistic regression analyses.

RESULTS

Among 468 consecutive patients with bleeding duodenal ulcers, 96 (20.5%) had endoscopically-confirmed PBDUs. PBDUs were more frequently observed in patients with a poor general condition in comparison to BDUs. The rates of rebleeding and in-hospital mortality in patients with PBDUs were approximately three times higher than those in patients with BDUs (PBDU vs. BDU: 29.2% vs. 10.2% [P < 0.0001] and 14.6% vs. 5.1% [P = 0.0029], respectively). Although the high in-hospital mortality in PBDUs could be explained, to a lesser extent, by the likelihood of rebleeding, and, to a greater extent, by the patients' poor general condition, the presence of a PBDU itself was largely responsible for the high rebleeding rates in PBDUs.

CONCLUSION

This is the first study focusing on the nature and treatment outcomes of bleeding PBDUs. PBDUs were associated with much higher rebleeding and mortality rates in comparison to BDUs, and the likelihood of rebleeding may be derived from their unique anatomic location.

Effects of anti-thrombotic drugs on all-cause mortality after upper gastrointestinal bleeding in Japan: A multicenter study with 2205 cases

OBJECTS

Although anti-thrombotic use is recognized as a risk factor for upper gastrointestinal bleeding (UGIB), there has been no clear evidence that it worsens the outcomes after the bleeding. The aim of this study is to investigate the effects of anti-thrombotic agents on in-hospital mortality following UGIB.

METHODS

Information on clinical parameters, including usage of anti-thrombotic agents, was retrospectively collected from consecutive patients with UGIB at 12 high-volume centers in Japan between 2011 and 2018. The all-cause in-hospital mortality rate was evaluated according to the usage of anti-thrombotic agents.

RESULTS

Clinical data were collected from 2205 patients with endoscopically confirmed UGIB. Six hundred and forty-five (29.3%) patients used anti-thrombotic agents. The all-cause in-hospital mortality rate was 5.7% (125 deaths). After excluding 29 cases in which death occurred due to end-stage malignancy, 96 deaths (bleeding-related, n = 22 ; non-bleeding-related, n = 74) were considered "preventable." Overall, the "preventable" mortality rate in anti-thrombotic users was significantly higher than that in non-users (6.0% vs. 3.7%, P < 0.05). However, the "preventable" mortality of anti-thrombotic users showed a marked improvement over time; although the rate in users remained significantly higher than that in non-users until 2015 (7.3% vs. 4.2%, P < 0.05), after 2016, the difference was no longer statistically significant (4.8% vs. 3.5%).

CONCLUSIONS

Although the usage of anti-thrombotic agents worsened the outcomes after UGIB, the situation has recently been improving. We speculate that the recent revision of the Japanese guidelines on the management of anti-thrombotic treatment after UGIB may have partly contributed to improving the survival of users of anti-thrombotic agents.

A simple prediction score for in-hospital mortality in patients with nonvariceal upper gastrointestinal bleeding

BACKGROUND

No prediction scores for the mortality of both inpatients and outpatients who developed nonvariceal upper gastrointestinal bleeding (UGIB) without endoscopic findings have been established. We aimed to derive and validate a novel prediction score for in-hospital mortality.

METHODS

We conducted a three-stage, multicenter retrospective study. In the derivation stage, patients with nonvariceal UGIB at six institutions were enrolled to derive the prediction score by logistic regression analysis. External validation of the score was performed to analyze discrimination by patients at six other institutions. Then the performance of this score was compared with that of four existing scores.

RESULTS

We enrolled 1380 and 825 patients in the derivation and validation cohorts, respectively. A prediction score (CHAMPS-R Score) comprising seven variables (Charlson Comorbidity Index ≥ 2, in-hospital onset, albumin < 2.5 g/dL, altered mental status, Eastern Cooperative Oncology Group performance status ≥ 2, steroids, and rebleeding) with equal-weight scores was established, with high discriminative ability in both derivation and validation cohorts (c statistic, 0.91 and 0.80, respectively). When rebeeding was excluded from the score (an onset model; CHAMPS Score), this score also achieved high discriminative ability (c statistic, 0.90 and 0.81, respectively). The prediction scores had significantly higher discriminative ability than the Glasgow Blatchford Score, AIMS65, ABC Score, and clinical Rockall Score in both cohorts (all, p < 0.05).

CONCLUSIONS

We derived and externally validated prediction scores for in-hospital mortality in patients with nonvariceal UGIB. The CHAMPS Score might be optimal for managing such patients. Its mobile application is freely available ( https://apps.apple.com/app/id1565716902 for iOS and https://play.google.com/store/apps/details?id=hatta.CHAMPS for Android).

Associations of PD-L1, PD-L2, and HLA class I expression with responses to immunotherapy in patients with advanced sarcoma: post hoc analysis of a phase 1/2 trial

BACKGROUND

Although immunotherapy is thought to be a promising cancer treatment, most patients do not respond to immunotherapy. In this post hoc analysis of a phase 1/2 study, associations of programmed death ligand 1 (PD-L1), PD-L2, and HLA class I expressions with responses to dendritic cells (DCs)-based immunotherapy were investigated in patients with advanced sarcoma.

METHODS

This study enrolled 35 patients with metastatic and/or recurrent sarcomas who underwent DC-based immunotherapy. The associations of PD-L1, PD-L2, and HLA class I expressions in tumor specimens, which were resected before immunotherapy, with immune responses (increases of IFN-γ and IL-12) and oncological outcomes were evaluated.

RESULTS

Patients who were PD-L2 (+) showed lower increases of IFN-γ and IL-12 after DC-based immunotherapy than patients who were PD-L2 (-). The disease control (partial response or stable disease) rates of patients who were PD-L1 (+) and PD-L1 (-) were 0% and 22%, respectively. Disease control rates of patients who were PD-L2 (+) and PD-L2 (-) were 13% and 22%, respectively. Patients who were PD-L1 (+) tumors had significantly poorer overall survival compared with patients who were PD-L1 (-). No associations of HLA class I expression with the immune response or oncological outcomes were observed.

CONCLUSIONS

This study suggests that PD-L1 and PD-L2 are promising biomarkers of DC-based immunotherapy, and that addition of immune checkpoint inhibitors to DC-based immunotherapy may improve the outcomes of DC-based immunotherapy.

Association between Sarcopenia and Overactive Bladder in Elderly Diabetic Patients

OBJECTIVES

To determine the association between sarcopenia and overactive bladder (OAB) in elderly diabetic patients using the Japanese version of SARC-F called SARC-F-J.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

The study included 329 elderly diabetic patients (aged ≥65 years) who regularly visited the outpatient clinic at Community hospital in Japan.

MEASUREMENTS

The condition of OAB was evaluated using the OAM symptom score, which involves a self-administered questionnaire, and sarcopenia was evaluated using the self-administered SARC-F-J questionnaire comprising five items. The odds ratio for OAB due to sarcopenia was calculated using multiple logistic regression analysis, with OAB as the dependent variable and sarcopenia as the explanatory variable.

RESULTS

A total of 329 patients (186 males, 143 females) were included for analysis in the present study. Of these patients, 22.9% had sarcopenia and 18.7% had OAB. After adjusting the variables, the odds ratio for OAB due to sarcopenia was 4.46 (95% confidence interval [CI], 1.14-17.36, P = 0.031) and 2.09 (95% CI, 0.52-8.26, P = 0.293) for males and females, respectively.

CONCLUSION

This study found that sarcopenia was significantly associated with OAB in elderly diabetic male patients based on SARC-F-J. Moreover, the possibility of the development of OAB should be considered during the medical examinations of elderly diabetic male patients with sarcopenia.

Vimentin-positive gastric adenocarcinoma arising in a hyperplastic polyp

We report a case of vimentin-positive early gastric adenocarcinoma arising in a hyperplastic polyp (HP). A 72-year-old Japanese man was admitted for the detailed examination of a gastric polyp. He had a subtotal gastrectomy due to acute abdomen 12 years ago. Upper endoscopy revealed a pedunculated polyp measuring approximately 2 cm on the greater curvature of upper body of the remnant stomach. Magnifying endoscopy revealed that the microsurface pattern was irregular and partially absent accompanied with irregular microvessels at the upper end of the polyp. We speculated that the lesion was an adenocarcinoma arising in the HP. Endoscopic submucosal dissection (ESD) was performed. Histological examination of the ESD specimen revealed that the lesion consisted of well- to poorly differentiated adenocarcinoma at the protruding lesion and foveolar hyperplastic epithelia at the base of the polyp. Immunohistochemically, most of tumor cells that comprised poorly-differentiated adenocarcinoma were positive for both cytokeratin and vimentin. Although carcinomas have occasionally been found in HPs, the histological features of the present case are considered extremely unusual. To the best of our knowledge, this is the first case of vimentin-positive early gastric carcinoma arising in a HP.

The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis

Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.

Multiferroic Dislocations in Ferroelectric PbTiO3

Ultrathin multiferroics with coupled ferroelectric and ferromagnetic order parameters hold promise for novel technological paradigms, such as extremely thin magnetoelectric memories. However, these ferroic orders and their functions inevitably disappear below a fundamental size limit of several nanometers. Herein, we propose a novel design strategy for nanoscale multiferroics smaller than the critical size limit by engineering the dislocations in nonmagnetic ferroelectrics, even though these lattice defects are generally believed to be detrimental. First-principles calculations demonstrate that Ti-rich PbTiO₃ dislocations exhibit magnetism due to the local nonstoichiometry intrinsic to the core structures. Highly localized spin moments in conjunction with the host ferroelectricity enable these dislocations to function as atomic-scale multiferroic channels with a pronounced magnetoelectric effect that are associated with the antiferromagnetic-ferromagnetic-nonmagnetic phase transitions in response to polarization switching. The present results thus suggest a new field of dislocation (or defect) engineering for the fabrication of ultrathin magnetoelectric multiferroics and ultrahigh density electronic devices.

Occlusal Force and Condylar Motion in Patients with Anterior Open Bite

Patients with open bite often show a weak occlusal force and temporomandibular disorders (TMDs). If these are the main cause of open bite, it may be hypothesized that both pre-pubertal and adult open-bite patients would show a weak occlusal force and abnormal condylar motion. The purpose of this study was to test this hypothesis. Test group subjects consisted of 13 consecutive pre-pubertal and 13 adult patients with anterior open bite. They were compared with age-matched normal subjects. The adult open-bite group showed a weaker occlusal force and a shorter range of condylar motion compared with the control subjects. In the pre-pubertal subjects, however, there were no significant differences in the occlusal force and range of condylar motion between the open-bite and control groups. Therefore, these results suggest that a weak occlusal force or TMDs may not be the main cause of open bite.

Multiferroic Domain Walls in Ferroelectric PbTiO3 with Oxygen Deficiency

Atomically thin multiferroics with the coexistence and cross-coupling of ferroelectric and (anti)ferromagnetic order parameters are promising for novel magnetoelectric nanodevices. However, such ferroic order disappears at a critical thickness in nanoscale. Here, we show a potential path toward ultrathin multiferroics by engineering an unusual domain wall (DW)-oxygen vacancy interaction in nonmagnetic ferroelectric PbTiO3. We demonstrate from first-principles that oxygen vacancies formed at the DW unexpectedly bring about magnetism with a localized spin moment around the vacancy. This magnetism originates from the orbital symmetry breaking of the defect electronic state due to local crystal symmetry breaking at the DW. Moreover, the energetics of defects shows the self-organization feature of oxygen vacancies at the DW, resulting in a planar-arrayed concentration of magnetic oxygen vacancies, which consequently changes the deficient DWs into multiferroic atomic layers. This DW-vacancy engineering opens up a new possibility for novel ultrathin multiferroic.

Multiferroic Vacancies at Ferroelectric PbTiO(3) Surfaces

Multiferroics in nanoscale dimensions are promising for novel functional device paradigms, such as magnetoelectric memories, due to an intriguing cross-coupling between coexisting ferroelectric and (anti)ferromagnetic order parameters. However, the ferroic order is inevitably destroyed below the critical dimension of several nanometers. Here, we demonstrate a new path towards atomic-size multiferroics while resolving the controversial origin of dilute ferromagnetism that unexpectedly emerges in nanoparticles of nonmagnetic ferroelectric PbTiO(3). Systematic exploration using predictive quantum-mechanical calculations demonstrates that oxygen vacancies formed at surfaces induce ferromagnetism due to local nonstoichiometry and orbital symmetry breaking. The localized character of the emerged magnetization allows an individual oxygen vacancy to act as an atomic-scale multiferroic element with a nonlinear magnetoelectric effect that involves rich ferromagnetic-antiferromagnetic-nonmagnetic phase transitions in response to switching of the spontaneous polarization.

Aortoesophageal fistula after thoracic endovascular aortic repair diagnosed and followed with endoscopy

A 70-year-old man reported dysphagia two months after undergoing thoracic endovascular aortic repair (TEVAR). An endoscopic examination revealed a fistula between the esophagus and the thoracic aortic aneurysm, and computed tomography (CT) showed that the thoracic aortic aneurysm had increased in size. The patient was diagnosed with an aortoesophageal fistula (AEF), and surgical replacement of the thoracic aorta was performed. AEFs are a rare but typically fatal complication after TEVAR. Physicians should consider a diagnosis of AEF and perform endoscopic examinations and CT in patients who undergo TEVAR and subsequently complain of dysphagia.

Stimulation of liver regeneration after hepatectomy in mice by injection of bone marrow mesenchymal stem cells via the portal vein

AIM

To investigate whether mouse bone marrow mesenchymal stem cells (BMC) stimulate liver regeneration after partial hepatectomy.

METHODS

Isolated BMCs were purified by density gradient centrifugation. We performed a 70% hepatectomy in male BALB/c mice followed by injection of BMCs into the portal vein (PV-BMC group), or the tail vein (IV-BMC group), or of saline into the portal vein (control group).

RESULTS

The wet weight of the liver remnant increased significantly in the PV-BMC group at 3 and 5 days after hepatectomy compared with the IV-BMC and control groups. The Ki-67 labeling index revealed that the increase to result from stimulation of DNA synthesis. The constitutive interleukin-6 and hepatocyte growth factor mRNAs in the remnant liver tended to increase in the PV-BMC group at 3 days after hepatectomy.

CONCLUSIONS

These results demonstrated that BMC injection into the portal vein enhanced liver growth after partial hepatectomy in mice.

MRI findings of mucoepidermoid carcinoma of the parotid gland: correlation with pathological features

OBJECTIVE

The aim of this study was to correlate the MRI appearance and pathological findings in each grade of the mucoepidermoid carcinoma (MEC) of the parotid gland.

METHODS

We reviewed surgically proven MECs of parotid glands in 20 patients. Pathologically, 5 tumours were high-grade, 3 were intermediate and 12 were low-grade. MR images were evaluated with emphasis on signal intensities on T(2) weighted images, margin characteristics and lymph node metastasis, correlating these with pathological features.

RESULTS

Among the high-grade MECs, four out of five tumours showed inhomogeneous low to intermediate signal intensity on T(2) weighted images, reflecting high cellularity. All tumours had an ill-defined margin, reflecting invasive tumour growth. Among the intermediate-grade MECs, all three tumours showed intermediate signal intensity on T(2) weighted images and two tumours had an ill-defined margin. Among the low-grade MECs, 11 of the 12 tumours had a hyperintense area on T(2) weighted images because of the existence of abundant mucin secreting cells. Seven tumours had an ill-defined margin, reflecting peritumoural inflammatory changes rather than invasive tumour growth. Lymph node metastasis was seen in three high-grade MECs.

CONCLUSION

MECs of the parotid gland show variable MRI findings reflecting their histological nature, which seems to have certain tendencies depending on the tumour grade.

Choledochal cyst associated with duodenal atresia: case report and review of the literature

We report a rare case of choledochal cyst (CC) associated with congenital duodenal atresia (DA) and annular pancreas (AP). A girl was born at 37 weeks of gestation weighing 2,974 g with a prenatal diagnosis of DA. She underwent a duodenoduodenostomy for type III DA with an AP 1 day after birth. At 4 years of age, she was admitted for evaluation of cholangitis and pancreatitis. Radiological studies demonstrated a fusiform-type CC with pancreaticobiliary maljunction (PBMJ). Excision of the CC and hepaticojejunostomy were performed. The patient was discharged without complications. Despite the fact that CC, DA, and AP are embryologically closely related entities, to the best of our knowledge, only eight such cases have been documented. We must be aware of the possible combination of CC in the follow-up of the patients with DA associated with AP.

[The strategy for aortic root reconstruction; Bentall operation or native valve preserving operation?]

Bentall operation has been a gold-standard procedure for the aortic root reconstruction in the patients with aortic root aneurysms and aortic valve insufficiency (AI). Recently, native aortic valve preserving operation has been widely spread. In this study, we described the results of aortic root reconstruction in our institution and evaluated our operative methods. We selected Bentall operation for severely damaged or cardiac redo cases, and David operation for simple annuloaortic ectasia and AI. Recently, we have utilized Valsalva graft which provides the advantage of capability of larger prosthetic valve implantation and better hemodynamic performance.

Therapeutic hypothermia can be induced and maintained using either commercial water bottles or a "phase changing material" mattress in a newborn piglet model

BACKGROUND

Therapeutic hypothermia, a safe and effective treatment for neonatal encephalopathy in an intensive care setting, is not available in low-resource settings. Aims/

METHODS

To assess two low-tech, low-cost cooling devices for use in low-resource settings: (i) commercially available water bottles filled with tepid water (25 degrees C); (ii) a mattress made of phase changing material (PCM) with a melting point of 32 degrees C (PCM works as a heat buffer at this temperature). Eleven anaesthetised newborn piglets were studied following transient hypoxia-ischaemia. The cooling device was applied 2-26 h after hypoxia-ischaemia with a target rectal temperature (T(rectal)) of 33-34 degrees C. T(rectal) undershoot was adjusted using cotton blankets; the cooling device was renewed when T(rectal) rose above 35 degrees C. T(rectal) data during cooling were dichotomised (within or without target) to assess: (a) the total period within the target T(rectal) range; (b) the stability and fluctuation of T(rectal) during cooling.

RESULTS

Therapeutic hypothermia was achieved with both water bottles (n = 5) and the PCM mattress (n = 6). The mean (SD) time to reach target T(rectal) was 1.8 (0.5) h with water bottles and 1.9 (0.3) h with PCM. PCM cooling led to a longer period within the target T(rectal) range (p<0.01) and more stable cooling (p<0.05). Water bottle cooling required device renewal (in four out of five piglets).

CONCLUSION

Simple, low-tech cooling devices can induce and maintain therapeutic hypothermia effectively in a porcine model of neonatal encephalopathy, although frequent fine tuning by adjusting the number of blankets insulating the piglet was required to maintain a stable temperature. PCM may induce more stable cooling compared with water bottles.

An animal model of intrinsic dental erosion caused by gastro-oesophageal reflux disease

OBJECTIVES

To explore the association between dental erosion and gastro-oesophageal reflux disease (GORD), we used an animal model of GORD.

MATERIALS AND METHODS

We performed an operation to force gastro-duodenal contents reflux in male Wistar rats, and examined the teeth in the reflux rats at 15 or 30 weeks postoperatively. Dental erosion was evaluated based on a slightly modified index from a previous report. Estimation of pH was employed in the oesophageal and gastric contents.

RESULTS

Macroscopically, dental erosion was only detected in the reflux rats. Histopathologically, dentin exposure was detected in three of the seven cases after 30 weeks. Alveolar bone destruction and osteomyelitis were also noted in severe cases. The pH of the oesophageal and stomach contents was 6.93 +/- 0.15 and 3.7 +/- 0.39, respectively.

CONCLUSIONS

We confirmed the relationship between dental erosion and GORD. First step of dental erosion caused by GORD is the loss of surface enamel induced by regurgitation of an acidic liquid and acidic gas. Subsequently, further destruction of dental hard tissues and tooth supporting structure is accelerated by mixed juice with gastric and duodenal contents. The reflux animal model is a useful tool to examine the mechanism of dental erosion in GORD.

Salivary duct carcinoma of the parotid gland: clinical and MR features in six patients

This study reports the clinical and MR features of salivary duct carcinoma (SDC) of the parotid gland, which is a rare and highly malignant tumour. We assessed retrospectively the clinical and MR features of six patients with histologically proven SDC of the parotid gland. The five men and one woman, ranging in age from 65-71 years (mean, 67 years), had undergone MRI before surgery. All patients presented with parotid masses and four patients had facial paralysis. Two had been aware of the parotid mass for more than 10 years. On MRI, all of the tumours had an ill-defined margin along either the entire circumference or part of the circumference. Four tumours showed infiltration into the subcutaneous or parapharyngeal space. Two tumours showed a wholly solid internal content, and four tumours had varying proportions of cystic content. The signal intensity of the solid portion was low to intermediate on both T(1) weighted and T(2) weighted images. Three patients showed multiple cervical lymph node swellings. Although SDC can show non-specific MRI findings, the combined findings (e.g. low-to-intermediate signal intensities on T(2) weighted images, ill-defined boundaries, infiltration into the surrounding fat space, facial nerve paralysis and associated cervical lymphoadenopathy, seem to suggest a high-grade malignancy.