Population-based incidence and outcomes of acute aortic dissection in Japan

Background

The population-based incidence and outcomes of acute aortic dissection (AAD) are still unknown because some patients are already dead on arrival at the hospital, and the accurate diagnosis of AAD is difficult due to the low autopsy rate for patients with cardiopulmonary arrest outside of the hospital. We performed a population-based review of all patients with AAD in a well-defined geographical area in the southern part of Japan between 2016 and 2018.

Methods

Data of all patients with AAD at our Hospital, which performs medical care for 120,000 residents, were collected retrospectively. The emergency medical service is dedicated to the transfer of all patients in this area to the MPNH. For all patients who were dead on arrival, the diagnosis of AAD was made by autopsy imaging (AI) using computed tomography. The age-adjusted incidence and mortality per 100,000 population were calculated using the Japanese population distribution model in 2015.

Results

The total incidence of AAD was 79 (type A: 64.5%, n=51). Of those, 60.8% (31/51) of patients with type A and 21.4% (6/28) with type B were dead on arrival and diagnosed by AI. The 30-day mortality rates after the onset of AAD were 74.5% (38/51) in type A and 25.0% (7/28) in type B. Excluding the dead-on-arrival patients, the 30-day mortality rates were 35.0% (7/20) in type A and 4.5% (1/22) in type B. The age-adjusted incidence and mortality of AAD per 100,000 inhabitants were 17.3 (type A: 11.3, type B: 6.0) and 9.6 (type A: 8.4, type B: 1.2), respectively. Both values were significantly higher in men than in women.

Conclusions

The population-based survey of emergency medical care for AAD showed that the age-adjusted incidence of AAD was two-fold higher than in previous reports, and the actual mortality rates after AAD onset were markedly higher due to the high incidence of dead-on-arrival.

Funding Acknowledgement

Type of funding sources: None. Representative CT images of type A AAD

Transmission of extended-spectrum β-lactamase-producing Klebsiella pneumoniae associated with sinks in a surgical hospital ward, confirmed by single-nucleotide polymorphism analysis

BACKGROUND

Although sink- and drain-related carbapenemase-producing Enterobacterales transmission has been reported previously, there is limited research regarding the transmission of extended-spectrum β-lactamase (ESBL)-producing Enterobacterales.

AIM

To investigate nosocomial ESBL-producing Klebsiella pneumoniae transmission via patient sinks and drains on a general surgical hospital ward.

METHODS

ESBL-producing K. pneumoniae transmission on a surgical ward at Tokyo Medical University Hospital (built in July 2019) from July 2019 to February 2020 was investigated. Information regarding the relatedness of the isolates from the patients and the environment was provided by whole-genome sequence analysis.

FINDINGS

Four clinical isolates of K. pneumoniae (TUM19831, TUM19832, TUM19833 and TUM19834) were detected during the study. TUM19831 was identified prior to moving to the new building and was detected again in the new building. TUM19832 and TUM19833 were detected in July 2019, and TUM19834 was detected in December 2019. TUM19835 and TUM19836 were detected in two different sinks and drains in July 2019, while a further two sinks and drains tested positive for TUM19837 and TUM19838 in February 2020. Whole-genome analysis revealed that all strains were ST307 and CTXM15 sequence types, and the isolates were indistinguishable by genetic analysis. Due to inadequate removal of the slime biofilm coating, the sinks needed to be cleaned again before TUM19837 and TUM19838 could be detected.

CONCLUSIONS

This study demonstrated the transmission of indistinguishable ESBL-producing K. pneumoniae strains from sinks and drains in the patient area of a general surgical hospital ward. There is a need to recognize this risk and develop optimal management strategies for plumbing systems in hospitals and other healthcare settings.

P–611 Innovative controlled ovarian stimulation (COS) for polycystic ovary syndrome (PCOS) produces high-quality oocytes and no ovarian hyper stimulation syndrome (OHSS)

Study question

How can we find an ovarian stimulation method that does not cause hyper stimulation syndrome but can produce a high pregnancy rate at one cycle?

Summary answer

This newly developed method for PCOS has a higher accumulative clinical outcome for one trial and no OHSS.

What is known already

Almost all conventional treatments for PCOS have managed to avoid OHSS by reducing the number of growing follicles, which are associated with high Estradiol levels and stimulate the production of vessel endothelial growth hormone (VEGF), leading to increased vessel permeability. Low dose FSH administration, In vitro maturation (IVM), Ovarian Drilling and Coasting have been performed to achieve this. However, their actual clinical outcome is still unsatisfactory.

Study design, size, duration

Evaluation of the efficiency of this method was conducted retrospectively at St. Mother Clinic. The embryonic development and the clinical outcome were studied for 34 PCOS patients during the period between November 2018 and December 2019.

Participants/materials, setting, methods

We started injections of FSH (150iu/ml), then we did ultrasound follicle monitoring. GnRH antagonist shots were started when the leading follicle reached 18mm and continued until the largest follicle was 22–24mm and the E2 value was over 4000pg/ml. Letrozole (2.5mg) and leuprorelin acetate (1.88mg) was injected as trigger. Two tablets each of Letrozole, Cabergoline and GnRH antagonist were given for 5 consecutive days after the oocyte retrieval. All embryos were cryopreserved.

Main results and the role of chance

Number of patients and cycles were 34 and 59. Average number of cryopreserved blastocysts was 6.12 (1–16). The frequencies of OHSS (mild, moderate, severe) were 29.4% (10/34), 0% (0/34), 0% (0/34). Average days between oocyte collection and withdrawal hemorrhage was 5.44(5–7). Cryopreservation rate was 100.0% (34/34). Clinical pregnancy rate and miscarriage rate was 42.3% (25/59) and 16.0% (4/25). The cumulative pregnancy rate was 73.7% (25/34). The four remaining unsuccessful cases still have 10,6,3 and 7 frozen embryos. So, there is a high possibility that they become successful, that would bring the cumulative pregnancy rate up to 82.3% (28/34).

Limitations, reasons for caution

This COS for PCOS seems promising, however it is premature to conclude that this method is established. This method requires caution monitoring for hormone level, follicle size and number and coagulant function. It also accompanied with the risk of ovarian hemorrhage on aspiration of a great number of oocytes.

Wider implications of the findings: This COS seems viable for PCOS cases. It could control the cohort of antral follicles with different doses of Letrozole to find the optimal COH method and it could become the first option for COS of PCOS.

Trial registration number

N/A

P–023 Innovative ultra-rapid vitrification method for five or fewer testicular spermatozoa from non-obstructive azoospermic men after microsurgical testicular sperm extraction (Micro-TESE)

Study question

What technique can be used to successfully cryopreserve five or fewer testicular spermatozoa from non-obstructive azoospermic men?

Summary answer

This method for cryopreserving five or fewer spermatozoa from non-obstructive azoospermic men showed a recovery rate above 90% and a survival rate of about 70%.

What is known already

Clinical outcomes of ICSI when using only five or fewer testicular spermatozoa after cryopreservation have been unsuccessful and are considered to be inferior to those using testicular fresh spermatozoa from Micro-TESE. A possible cause of these poor results has been the lack of a successful freezing technique. In these cases, repeated Micro-TESE and simultaneous oocyte pick up has been the only available treatment.

Study design, size, duration

Evaluation of the efficiency of cryopreservation by modified permeable cryoprotectant-free vitrification method (HTF supplemented with 0.1M sucrose and 10% SPS) for five or fewer testicular spermatozoa from 113 non-obstructive azoospermic men using Micro-TESE was conducted retrospectively at St. Mother Clinic between 2011 and 2018.

Participants/materials, setting, methods

This study included 113 non-obstructive azoospermic men. Each motile spermatozoon was carefully aspirated tail first into the pipette, put into a 2-μl microdroplet media of the vitrification medium near the tip of the Cryotop (Kitazato Corporation, Tokyo, Japan) submerged in liquid nitrogen vapor for 2 min and then immediately plunged in liquid nitrogen. The vitrified spermatozoa were warmed by dipping them into a droplet media. Successfully recovered motile sperm were selected and used for ICSI.

Main results and the role of chance

Number of patients, transfer cycles and collected sperms were 113, 192 and 560. Mean age of patients and their wives were 32.0±3.7y and 28.4±5.8y. Clinical pregnancy rate, miscarriage rate, live birth rate and number of live offspring were 24.0% (46/192), 19.6% (9/46), 19.3% (37/192) and 37 (Male: Female = 17: 20). Sperm recovery rate and survival rate were 90.3% (506/560) and 70.4% (356/506). Fertilization rate and mean number of transferred embryos were 51.6% (99/192) and 1.73 (1–2). Mean gestational weeks and mean body weight at birth were 39.23±5.27w and 2852.31±314.28g. No congenital anomalies were observed in any of the babies.

Limitations, reasons for caution

The maximum number of spermatozoa to which this method can be applied successfully is about 10. When the number of aspirated spermatozoa is over 10, some of them change direction and reach the mineral oil, and once this happens, they cannot be expelled out of the pipette.

Wider implications of the findings: This technique is very useful for the cryopreservation of very small numbers of testicular spermatozoa (fewer than 10) in order to avoid or reduce Micro-TESE interventions.

Trial registration number

N/A

The structure of aqueous solutions of hexafluoro-iso-propanol studied by neutron diffraction with hydrogen/deuterium isotope substitution and empirical potential structure refinement modeling

Neutron diffraction measurements of H/D isotopic substitution are made at room temperature for seven H/D substituted hexafluoro-iso-propanol (HFIP; 1,1,1,3,3,3-hexafluoro-2-propanol)-water mixtures at 0.1, 0.2, and 0.4 HFIP mole fraction (xHFIP). The eight partial structure factors except for the H(CH)-H(CH) pair obtained are subjected to an empirical potential structure refinement (EPSR) method to derive all site-site pair correlation functions. It is found that with increasing HFIP concentration the ice-like network of water disappears between xHFIP = 0.1 and 0.2, followed by the formation of a chain-like water structure embedded in an intrinsic structure of HFIP evolved at xHFIP = 0.4. The hydroxyl group of HFIP forms hydrogen bonds with the surrounding water molecules at all HFIP mole fractions investigated. There is no evidence that the water structure is well defined around the CF3 groups of HFIP, but water molecules surround tangentially the CF3 groups of HFIP.

Non-target Impact of Dinotefuran and Azoxystrobin on Soil Bacterial Community and Nitrification

Pesticides to protect crops from pests are subject to rigorous risk assessment before registration in Japan. However, further information needs to be collected regarding the assessment of impacts on the natural environment. In particular, nitrifying bacteria play a role in converting ammonium salts to nitrates in soil. However, there is limited research covering the effects of insecticides on nitrification, despite several fungicides and herbicides have an inhibitory effect on nitrifying bacteria. Therefore, we investigated the effect of pesticides on the nitrification when applied to soil. The application of both pesticides promoted ammonia oxidation, and suppressed nitrite oxidation in a high-concentration treatment of dinotefuran. In addition, it was clarified that the diversity and species richness of soil bacteria was significantly reduced when the pesticides were applied to the soil, and that the specific soil bacteria (Metyhlotenera spp.) dominated the application of the pesticides.

Effect of administering activated lymphocytes originated from the dam on the immune cell reaction in Holstein calves

Injection of lymphokine activated killer (LAK) cells is known as useful for activation of cellular immune system. Although the effect of LAK cells has been clarified in human or mice, this effect on function of immune cells has not been examined in calves. Healthy ten Holstein calves were injected with the LAK cells 2 days after birth (LAK Group), and another eight calves were observed as controls (Control Group). All calves received the colostrum formulation on the day of birth, and then, were inoculated with a live attenuated vaccine of bovine herpesvirus (BHV)-1 at 2 (the first vaccination) and 6 (the second vaccination) weeks after birth. Peripheral blood of their dam obtained 3 weeks before calving was used for preparation of LAK cells. Blood samples were taken prior to vaccine inoculation and 3 days after the first inoculation, as well as 3 and 6 days after the second vaccination from all calves. Numbers of CD8+ and CD21+ cells increased significantly after the second vaccination in the LAK Group compared with Control Group. The present study suggested the improved effect of injecting LAK cells originated from dams on immune cells function of young calves after BHV-1 live vaccine.

Impact of muscle volume loss on acute oral mucositis in patients undergoing concurrent chemoradiotherapy after oral cancer resection

This study evaluated the association between skeletal muscle mass depletion and severe oral mucositis in patients undergoing concurrent chemoradiotherapy after oral cancer resection. Skeletal muscle mass was evaluated in 60 patients using the skeletal muscle index, which was based on skeletal muscle cross-sectional area (on computed tomography) at the level of the third lumbar vertebra. In accordance with the grading criteria of the Radiation Therapy Oncology Group, patients with a grade ≥3 were defined as having severe oral mucositis. Multivariate logistic regression analysis was used to evaluate independent risk factors for severe oral mucositis. Eleven patients (18.3%) were diagnosed with low skeletal muscle mass. Severe oral mucositis occurred in 17 (28.3%) patients, and the mean skeletal muscle index was 42.8 cm²/m². A low skeletal muscle mass (hazard ratio 18.1; P=0.001) and a chemotherapy regimen consisting of 5-fluorouracil and cisplatin (versus cisplatin only) (hazard ratio 5.5; P=0.015) were independent risk factors for severe oral mucositis. Future prospective studies are warranted to identify effective pre- and perioperative exercises and nutrition programmes to increase low skeletal muscle mass and reduce the incidence of severe oral mucositis in patients undergoing concurrent chemoradiotherapy after oral cancer resection.

Impact of endovascular repair on the outcomes of octogenarians with ruptured abdominal aortic aneurysms: a nationwide Japanese study

Objective

This study aimed to clarify the impact of endovascular aneurysm repair (EVAR) on clinical outcomes in Japanese patients of advanced age with ruptured abdominal aortic aneurysm (rAAA).

Methods

This was a national registry based retrospective comparative study, using data from the Japanese Registry Of All cardiac and vascular Diseases-Diagnostic Procedure Combination (JROAD-DPC), a nationwide claim based database from more than 600 hospitals. Patients admitted with rAAA between April 1, 2012, and March 31, 2015 were included in the study. Patient characteristics, management, and outcomes were compared between the elderly (aged ≥80 y) and the less old. The primary endpoint was in hospital mortality; the secondary endpoint was the functional status at discharge.

Results

Of 3 969 eligible patients, 49.9% were categorised as elderly. Elderly patients had a higher prevalence of female gender (41.8% vs. 17.0%, p<0.001) and disturbance of consciousness on admission (28.6% vs. 20.7%, p<0.001). They were less likely to undergo open surgical repair (31.6% vs. 56.7%, p<0.001), although EVAR was performed similarly in both groups (13.7% vs. 14.8%, p<0.33). The unadjusted mortality rate (61.8% vs. 37.6%, p<0.001) and mean Barthel index at discharge (73.0 vs. 91.8, p<0.001) were statistically significantly worse in the elderly. Multilevel mixed effect logistic regression analyses showed that old age was detected as an independent predictor of in hospital death (odds ratio 2.75; 95% confidence interval, 2.39–3.17; p<0.001). However, for patients who received EVAR, old age was not statistically significant (odds ratio 1.13; 95% confidence interval, 0.77–1.66; p<0.53).

Conclusion

Elderly patients with rAAA were less likely to be offered open surgical repair, and the mortality among those who received surgery was high. However, for the small subgroup of elderly patients currently selected for EVAR there was a favourable outcome. The further implementation of EVAR for rAAA in Japan, especially for elderly patients with suitable anatomy, may be justified.

Funding Acknowledgement

Type of funding source: None

An artificial impact on the asteroid (162173) Ryugu formed a crater in the gravity-dominated regime

The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.

Swelling of Doubly Magic ^{48}Ca Core in Ca Isotopes beyond N=28

Interaction cross sections for ^{42-51}Ca on a carbon target at 280  MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.

Long-term follow-up of the randomized trial of mesorectal excision with or without lateral lymph node dissection in rectal cancer (JCOG0212)

BACKGROUND

Japan Clinical Oncology Group (JCOG) 0212 (ClinicalTrials.gov NCT00190541) was a non-inferiority phase III trial of patients with clinical stage II-III rectal cancer without lateral pelvic lymph node enlargement. The trial compared mesorectal excision (ME) with ME and lateral lymph node dissection (LLND), with a primary endpoint of recurrence-free survival (RFS). The planned primary analysis at 5 years failed to confirm the non-inferiority of ME alone compared with ME and LLND. The present study aimed to compare ME alone and ME with LLND using long-term follow-up data from JCOG0212.

METHODS

Patients with clinical stage II-III rectal cancer below the peritoneal reflection and no lateral pelvic lymph node enlargement were included in this study. After surgeons confirmed R0 resection by ME, patients were randomized to receive ME alone or ME with LLND. The primary endpoint was RFS.

RESULTS

A total of 701 patients from 33 institutions were assigned to ME with LLND (351) or ME alone (350) between June 2003 and August 2010. The 7-year RFS rate was 71.1 per cent for ME with LLND and 70·7 per cent for ME alone (hazard ratio (HR) 1·09, 95 per cent c.i. 0·84 to 1·42; non-inferiority P = 0·064). Subgroup analysis showed improved RFS among patients with clinical stage III disease who underwent ME with LLND compared with ME alone (HR 1·49, 1·02 to 2·17).

CONCLUSION

Long-term follow-up data did not support the non-inferiority of ME alone compared with ME and LLND. ME with LLND is recommended for patients with clinical stage III disease, whereas LLND could be omitted in those with clinical stage II tumours.