Physiological and genomic analysis of newly-isolated polysaccharide synthesizing cyanobacterium Chroococcus sp. FPU101 and chemical analysis of the exopolysaccharide

A unicellular cyanobacterium that produces a large amount of exopolysaccharide (EPS) was isolated. The isolate, named Chroococcus sp. FPU101, grew between 20 and 30°C and at light intensities between 10 and 80 μmol m^-2 s^-1. Purified EPS from Chroococcus sp. FPU101 had a molecular size of 5.9 × 10³ kDa and contained galactose, rhamnose, fucose, xylose, mannose, glucose, galacturonic acid, and glucuronic acid at a molar ratio of 17.2:15.9:14.1:11.0:9.6:9.5:13.0:9.7. The EPS content significantly increased when the NaCl concentration in the medium was increased from 1.7 to 100 mM. However, high NaCl concentrations did not significantly affect the molecular size or chemical composition of the EPS. The genes wza, wzb, wzc, wzx, wzy, and wzz that are involved in EPS synthesis were conserved in the genome of Chroococcus sp. FPU101, which was sequenced in this study. These results suggest that the Wzy-dependent pathway is potentially involved in EPS production in this organism.

Ion tracks in silicon formed by much lower energy deposition than the track formation threshold

Damaged regions of cylindrical shapes called ion tracks, typically in nano-meters wide and tens micro-meters long, are formed along the ion trajectories in many insulators, when high energy ions in the electronic stopping regime are injected. In most cases, the ion tracks were assumed as consequences of dense electronic energy deposition from the high energy ions, except some cases where the synergy effect with the nuclear energy deposition plays an important role. In crystalline Si (c-Si), no tracks have been observed with any monomer ions up to GeV. Tracks are formed in c-Si under 40 MeV fullerene (C₆₀) cluster ion irradiation, which provides much higher energy deposition than monomer ions. The track diameter decreases with decreasing the ion energy until they disappear at an extrapolated value of ~ 17 MeV. However, here we report the track formation of 10 nm in diameter under C₆₀ ion irradiation of 6 MeV, i.e., much lower than the extrapolated threshold. The diameters of 10 nm were comparable to those under 40 MeV C₆₀ irradiation. Furthermore, the tracks formed by 6 MeV C₆₀ irradiation consisted of damaged crystalline, while those formed by 40 MeV C₆₀ irradiation were amorphous. The track formation was observed down to 1 MeV and probably lower with decreasing the track diameters. The track lengths were much shorter than those expected from the drop of S_e below the threshold. These track formations at such low energies cannot be explained by the conventional purely electronic energy deposition mechanism, indicating another origin, e.g., the synergy effect between the electronic and nuclear energy depositions, or dual transitions of transient melting and boiling.

1215 Improving Sleep Disorders And Chronic Neck Pain By Adjusting Height Of The Pillow Through Cervical Posture Management

Introduction

Recent studies have suggested that chronic musculoskeletal system pain, including chronic neck pain, accounts for approximately 70% of all sleeping disorders. Simultaneously, sleeping disorders increase pain sensitivity and create a vicious cycle of chronic neck pain. Patients with chronic pain experience a variety of somatic symptoms (e.g., Stomach or bowel problems, Back pain, Pain in your joints, headaches, chest pain, shortness of breath, dizziness, fatigue, and Trouble sleeping) that are difficult to treat. However, treatment of both neck chronic pain and sleeping disorders through cervical posture management by adjusting height of the pillow used while sleeping has yet to be considered.

Methods

Patients who visited our hospital with chief complaints of chronic neck pain were rated according to the Numerical Rating Scale (NRS) and were asked to answer the Somatic Symptom Scale-8 (SSS-8), to ascertain the degree of somatic symptoms. Out of all the patients, only 84 scored at least 8 out of 32 in the SSS-8. Based on the individual results of the 84 respondents, they were given customized pillows to be used for 3 months. The pillows were adjusted using the SSS method developed at our clinic. We adjusted the height of the pillow by 5mm increments to check the cervical inclination angle at approximately 15 degrees in supine position, lateral position with the center line from face to neck at left-right symmetry and finally confirming smooth turning over. The respondents performed NRS and SSS-8 after 2 weeks and 3 months of using the pillow.

Results

The results of this study showed that at 0 weeks / 2 weeks / 3 months. NRS score was 6.8 / 5.1 / 4.1 (p <0.01), and the overall SSS-8 score was 13.2 / 9.9 / 8.2 (p <0.01), showed a marked improvement. By symptom, all symptoms except Stomach or bowel problems showed significant improvement. Trouble sleeping showed the highest improvement at 2.6 / 1.7 / 1.3 (p <0.01).

Conclusion

Chronic neck pain and sleeping disorders improved in the patients. These results suggested that cervical posture management by adjusting height of the pillow is an effective treatment method.

Support

None

Sequentially addressable dielectrophoretic array for high-throughput sorting of large-volume biological compartments

Droplet microfluidics has become a powerful tool in precision medicine, green biotechnology, and cell therapy for single-cell analysis and selection by virtue of its ability to effectively confine cells. However, there remains a fundamental trade-off between droplet volume and sorting throughput, limiting the advantages of droplet microfluidics to small droplets (<10 pl) that are incompatible with long-term maintenance and growth of most cells. We present a sequentially addressable dielectrophoretic array (SADA) sorter to overcome this problem. The SADA sorter uses an on-chip array of electrodes activated and deactivated in a sequence synchronized to the speed and position of a passing target droplet to deliver an accumulated dielectrophoretic force and gently pull it in the direction of sorting in a high-speed flow. We use it to demonstrate large-droplet sorting with ~20-fold higher throughputs than conventional techniques and apply it to long-term single-cell analysis of Saccharomyces cerevisiae based on their growth rate.

Impact of technically qualified surgeons on laparoscopic colorectal resection outcomes: results of a propensity score-matching analysis

Background

The Endoscopic Surgical Skill Qualification System (ESSQS) was introduced in Japan to improve the quality of laparoscopic surgery. This cohort study investigated the short‐ and long‐term postoperative outcomes of colorectal cancer laparoscopic procedures performed by or with qualified surgeons compared with outcomes for unqualified surgeons.

Methods

All laparoscopic colorectal resections performed from 2010 to 2013 in 11 Japanese hospitals were reviewed retrospectively. The procedures were categorized as performed by surgeons with or without the ESSQS qualification and patients' clinical, pathological and surgical features were used to match subgroups using propensity scoring. Outcome measures included postoperative and long‐term results.

Results

Overall, 1428 procedures were analysed; 586 procedures were performed with ESSQS‐qualified surgeons and 842 were done by ESSQS‐unqualified surgeons. Upon matching, two cohorts of 426 patients were selected for comparison of short‐term results. A prevalence of rectal resection (50·3 versus 40·5 per cent; P < 0·001) and shorter duration of surgery (230 versus 238 min; P = 0·045) was reported for the ESSQS group. Intraoperative and postoperative complication and reoperation rates were significantly lower in the ESSQS group than in the non‐ESSQS group (1·2 versus 3·6 per cent, P = 0·014; 4·6 versus 7·5 per cent, P = 0·025; 1·9 versus 3·9 per cent, P = 0·023, respectively). These findings were confirmed after propensity score matching. Cox regression analysis found that non‐attendance of ESSQS‐qualified surgeons (hazard ratio 12·30, 95 per cent c.i. 1·28 to 119·10; P = 0·038) was independently associated with local recurrence in patients with stage II disease.

Conclusion

Laparoscopic colorectal procedures performed with ESSQS‐qualified surgeons showed improved postoperative results. Further studies are needed to investigate the impact of the qualification on long‐term oncological outcomes.

Investigation of the time interval of plasma generation for a high repetition rate laser ion source

To apply a laser ion source that generates a high-intensity pulsed beam to high-dose applications, such as ion implantation, a high repetition rate operation with a short pulse interval is required. However, when the pulse interval is shortened, there is a concern that a plasma, which is different from a single pulse plasma generation, may be formed due to the interaction between the preceding and following pulses. We investigated the time interval in which plasma pulses are generated without pulse-to-pulse interaction using a laser ion source with two lasers. In the experiment, a graphite target was irradiated by two laser beams (1064-nm wavelengths) with the same pulse widths (5.4 ns) and energies (15 mJ, 30 mJ, and 45 mJ) at different time intervals ranging from 1000 μs to 0 µs, and the time integrated value corresponding to the total charge amount was calculated from the measured time-of-flight signal of the generated carbon ion current. It was observed that the total charge did not change when the time interval was as low as approximately 100 µs, and the total charge rapidly decreased when the time interval was below approximately 100 µs. Thus, it was determined that the interaction occurs within a time interval of approximately 100 µs.

Wire-loop lesion is associated with serological immune abnormality, but not renal prognosis, in lupus nephritis

BACKGROUND

Wire-loop lesion (WL) is one of the active lesions of lupus nephritis (LN). However, few reports have focused on the clinicopathological relationships of WL to serological immune abnormality and renal prognosis.

METHODS

We enrolled 126 Japanese LN patients subjected to renal biopsy in 11 hospitals from 2000 to 2018. In patients with class III or IV of the International Society of Nephrology/Renal Pathology Society classification, we retrospectively compared clinicopathological findings between those with WL (WL+ group) and without WL (WL- group) to detect factors associated with WL. Chronic kidney disease (CKD) was defined as an estimated glomerular filtration rate of <60 mL/min/1.73m² for more than three months. We also compared these findings between those with CKD (CKD+ group) and without CKD (CKD- group) at the last visit to investigate factors associated with renal prognosis.

RESULTS

Of 126 patients, 100 (79.4%) were classified as class III or IV. WL was found in 36 (36.0%) of them. Although the renal function did not differ, the WL+ group had a higher titre of serum anti-dsDNA antibodies and lower serum complement 3 levels than the WL- group. Linear regression analysis revealed a significant association only between anti-dsDNA antibodies and WL (β = 0.27, 95% confidence interval (CI) 0.001-0.100, p = 0.01). Of these patients, 69 were tracked for 59.6 ± 55.1 months. Kaplan-Meier analysis showed no difference in renal prognosis between these groups. Next, the CKD+ group included 15 (22.1%) patients. They were older and had higher frequencies of hypertension and hyperuricaemia, serum creatinine (Cr) level, glomerulosclerosis, interstitial inflammation, interstitial fibrosis and tubular atrophy than the CKD- group at the time of renal biopsy. The frequency of WL was not significantly different. Cox regression analysis revealed significant associations of CKD with hypertension, hyperuricaemia, serum Cr level at the time of renal biopsy clinically and with tubular atrophy histologically.

CONCLUSIONS

WL was associated with serum anti-dsDNA antibodies but not with renal prognosis, suggesting that WL reflects immune abnormality but is not an independent factor predictive of renal prognosis in LN.

Metal Artifact Reduction in Head CT Performed for Patients with Deep Brain Stimulation Devices: Effectiveness of a Single-Energy Metal Artifact Reduction Algorithm

BACKGROUND AND PURPOSE

Deep brain stimulation electrodes induce massive artifacts on CT images, deteriorating the diagnostic value of examinations. We aimed to investigate the usefulness and potential limitations of a single-energy metal artifact reduction algorithm in head CT performed in patients with implanted deep brain stimulation devices.

MATERIALS AND METHODS

Thirty-four patients with deep brain stimulation (bilateral, n = 28) who underwent head CT on a 320-detector row scanner and whose images were reconstructed with and without single-energy metal artifact reduction at the examinations were retrospectively included. The severity of artifacts around electrodes was assessed objectively using SDs and an artifact index. Two radiologists subjectively evaluated the severity of artifacts from electrodes, the visibility of electrode localization and surrounding structures, and overall diagnostic confidence on 4-point scales. Background image quality (GM-WM contrast and image noise) was subjectively and objectively assessed. The presence and location of artifacts newly produced by single-energy metal artifact reduction were analyzed.

RESULTS

Single-energy metal artifact reduction provided lower objective and subjective metal artifacts and improved visualization of electrode localization and surrounding structures and diagnostic confidence compared with non-single-energy metal artifact reduction images, with statistical significance (all, P < .01). No significant differences were observed in GM-WM contrast and image noise (all, P ≥ .11). The new artifacts from single-energy metal artifact reduction were prominently observed in patients with bilateral deep brain stimulation at high convexity, possibly induced by deep brain stimulation leads placed under the parietal scalp.

CONCLUSIONS

Single-energy metal artifact reduction substantially reduces the metal artifacts from deep brain stimulation electrodes and improves the visibility of intracranial structures without affecting background image quality. However, non-single-energy metal artifact reduction images should be simultaneously reviewed to accurately assess the entire intracranial area, particularly in patients with bilateral deep brain stimulation.

Low-charge-state ion production by a laser ion source for the TIARA ion implanter

Ion implanters require various kinds of heavy-ion beams in low-charge states for material science experiments. For this purpose, a laser ion source has been developed for the ion implanter at Takasaki Ion Accelerators for Advanced Radiation Application. In this study, we investigated the particle number of ions per laser pulse for each charge state in the laser-produced carbon plasma. In the experiment, the carbon plasma was generated from a graphite target using a Nd:YAG laser (1064 nm wavelength, 5 ns pulse width) at a laser energy of 37.5 mJ, 28.3 mJ, or 15.6 mJ. The particle number of ions in the plasma was evaluated from the time-integrated value of each ion-charge-state's current signal by placing the focusing lens at various positions. We found that the particle number of carbon ions was the highest for singly charged ions at all laser energies, with particle number in the order of 10¹⁰ ions obtained at a 1-m distance from the target surface.

Effects of depression on the condition of older inpatients with fracture and preexisting cognitive impairment

AIM

Few studies of depression have examined older inpatients with fracture and preexisting cognitive impairment. The current study sought to confirm whether depression affects the condition of older inpatients with fracture who also have cognitive impairment, and to investigate the extent to which depression affects activities of daily living.

METHODS

This was a retrospective cross-sectional study. The subjects were older inpatients with fracture and preexisting cognitive impairment. We examined data within 1 week of hospitalization, obtained from medical records. The data included demographic information, the motor Functional Independence Measure, Charlson Comorbidity Index, Mini-Mental State Examination, Geriatric Depression Scale 15, Geriatric Nutritional Risk Index, Skeletal Muscle Index and maximum grip strength test. These variables were compared between the two groups (with and without depression), and multiple regression analysis was performed with the motor Functional Independence Measure as the dependent variable.

RESULTS

The subjects were 68 patients. Only the motor Functional Independence Measure was significantly lower in the depression group than the non-depression group. Multiple regression analysis confirmed that depression strongly affected activities of daily living.

CONCLUSIONS

In considering the recovery of older inpatients with fracture and preexisting cognitive impairment, it is important to take the effects of depression into account.Implications for rehabilitationThe number of older fracture inpatients with cognitive impairment is predicted to increase, and such patients have a high prevalence of depression.Depression strongly affected Activities of Daily Living in older inpatients with fracture and pre-existing cognitive impairment.Focusing on depression assessment and intervention is important for rehabilitation of older fracture inpatients with cognitive impairment.