Differences in cervical sagittal alignment between the standing and sitting positions

BACKGROUND

Sagittal spinal alignment has mainly analyzed in the standing position. According to previous studies, there are significant differences in lumbopelvic alignment between the standing and sitting positions and cervical alignment is affected by lumbopelvic alignment. In this study, therefore, we hypothesized that cervical sagittal alignments are different between the standing and sitting positions.

METHODS

A total of 108 patients with spinal degenerative diseases underwent whole spine radiography. Cervical lordosis (CL), C2-7 SVA, T1S, C7-S1 SVA, TK, LL, SS, PT, and PI were measured in the standing and sitting positions. Patients were classified into 3 groups according to the changes in CL (ΔCL, CL in the sitting position - CL in the standing position); ΔCL < -3° (Decreased group: DG; 28.7%), -3° ≤ ΔCL ≤ 3° (Unchanged group: UG; 41.7%), and ΔCL > 3° (Increased group: IG; 29.6%).

RESULTS

The parameters of the UG in the standing position were closer to the ideal alignment (SRS-Schwab classification). In the DG, CL, T1S, and C7-S1 SVA in the standing position were significantly higher than in the UG. In the IG, PI-LL in the standing position was significantly higher than in the UG. In the sitting position, pelvis was rotated posteriorly (decrease in SS and increase in PT) and lumbar lordosis was flattened (decrease in LL) in all groups, and C2-7 SVA was significantly higher in the DG than in the UG.

CONCLUSIONS

CL was different between the standing and sitting positions in 58.3% of individuals. However, patients with good spinal sagittal alignment appeared to not undergo any changes in cervical alignment. Our results suggest the possibility that patients who had a positive imbalance and large PI-LL mismatch in the standing position had decreased CL and increased CL, respectively, when in the sitting position.

P5366Eicosapentaenoic acid therapy is associated with decreased coronary plaque instability assessed using optical frequency domain imaging

Background

The relationship between eicosapentaenoic acid (EPA) therapy and coronary plaque stability assessed by optical frequency domain imaging (OFDI) has not been thoroughly described.

Hypothesis

EPA therapy is associated with decreased plaque instability in patients undergoing percutaneous coronary intervention (PCI) using OFDI.

Methods

Data on coronary artery plaques from 121 patients presenting with acute coronary syndrome or stable angina who consecutively underwent PCI between October 2015 and July 2018 were retrospectively analyzed. Of these patients, 109 were untreated (no-EPA group), whereas 12 were treated with EPA (EPA group). Each plaque's morphological characteristics were analyzed using OFDI.

Results

We used 1:4 propensity score matching for patients who received or did not receive EPA therapy before PCI. Baseline characteristics were balanced between both groups (age, sex, body mass index, diabetes mellitus, hypertension, dyslipidemia, chronic kidney disease, smoking, previous PCI or coronary artery bypass grafting, previous myocardial infarction, prior statin use, acute coronary syndrome, hemoglobin A1c level, low-density lipoprotein cholesterol concentration, triglyceride concentration, and high-density lipoprotein cholesterol concentration). The EPA group had significantly lower mean lipid index (818±806 vs. 1,574±891) and macrophage grade (13.5±5.9 vs. 19.3±7.4) but higher mean minimum fibrous cap thickness (109.2±55.7 vs. 81.6±36.4 μm) than the no-EPA group (P=0.010, 0.019, and 0.040, respectively). Multiple logistic regression analyses showed that prior EPA use was independently associated with lower lipid index and macrophage grade (P=0.043 and 0.024, respectively).

Conclusion

This OFDI analysis suggests that EPA therapy is associated with decreased plaque instability in patients undergoing PCI.

Acknowledgement/Funding

None

Prognostic impact of residual lateral lymph node metastasis after neoadjuvant (chemo)radiotherapy in patients with advanced low rectal cancer

Background

There is a lack of large studies focusing on the prognostic significance of lateral lymph node (LLN) metastasis following LLN dissection (LLND) in rectal cancer. The aim of this study was to evaluate the prognostic impact of LLN metastases on survival of patients with advanced low rectal cancer.

Methods

Consecutive patients with locally advanced, but not metastatic, extraperitoneal rectal cancer treated with neoadjuvant (chemo)radiotherapy plus total mesorectal excision between 2004 and 2015 were included in the study. LLND was performed when pretreatment imaging documented enlarged LLNs (7 mm or greater in size). Localization of nodal metastases and long‐term outcomes were analysed. Kaplan–Meier analysis was used to compare the survival of patients with ypN0 disease with that of patients with mesorectal ypN+/LLN− status and patients with positive LLNs. The Cox proportional hazards model was used to evaluate predictors of disease‐free survival (DFS) and local recurrence.

Results

A total of 613 patients were included in the study; LLND was performed in 212 patients (34·6 per cent) and 57 (9·3 per cent) had LLN metastasis. Patients with LLN metastasis had improved DFS and local recurrence cumulative incidence rates compared with patients with mesorectal ypN2+/LLN− disease (DFS: P = 0·014; local recurrence: P = 0·006). Although the DFS rate of patients with LLN metastasis was worse than that of patients with ypN0 disease (P < 0·001), the cumulative incidence of local recurrence was similar (P = 0·491). In multivariable analysis, residual LLN metastasis was not an independent predictor of worse DFS or local recurrence.

Conclusion

LLN metastasis is not an independent predictor of local recurrence or survival. Survival of patients presenting with LLN metastasis after (chemo)radiotherapy was intermediate between that of patients with ypN0 status and those with mesorectal ypN2 positivity.

IMAGING URANIUM DISTRIBUTION ON RAT KIDNEY SECTIONS THROUGH DETECTION OF ALPHA TRACKS USING CR-39 PLASTIC NUCLEAR TRACK DETECTOR

Uranium is renowned as a global contaminant, and attracts major concern with regards to the health risks involved because its nephrotoxicity. This paper discusses the development of a simple method to identify accumulated regions or localized sites of uranium within kidneys using the CR-39 plastic nuclear track detector. To demonstrate the proposed method, renal cryo-sections (5 μm-t) from Wistar male rats, subcutaneously administered with uranyl acetate (2 mg/kg), were prepared on day one after administration. Concerned sections were subsequently placed on CR-39, stored for 1.25 years, and then etched in a 7 M NaOH solution at 70°C for 3 h. α-tracks were then detected in the form of etch pits, corresponding to uranium, and also the tissue shape and structure were transferred as a roughness on the surface of CR-39. As observed, the proposed method served to facilitate simultaneous detection and identification of localized regions of uranium accumulation within kidneys.

BYSTANDER WI-38 CELLS MODULATE DNA DOUBLE-STRAND BREAK REPAIR IN MICROBEAM-TARGETED A549 CELLS THROUGH GAP JUNCTION INTERCELLULAR COMMUNICATION

Bi-directional signaling involved in radiation-induced bystander effect (RIBE) between irradiated carcinoma cells and their surrounding non-irradiated normal cells is relevant to radiation cancer therapy. Using the SPICE-NIRS microbeam, we delivered 500 protons to A549-GFP lung carcinoma cells, stably expressing H2B-GFP, which were co-cultured with normal WI-38 cells. The level of γ-H2AX, a marker for DNA double-strand breaks (DSB), was subsequently measured up to 24-h post-irradiation in both targeted and bystander cells. As a result, inhibition of gap junction intercellular communication (GJIC) attenuated DSB repair in targeted A549-GFP cells, and suppressed RIBE in bystander WI-38 cells but not in distant A549-GFP cells. This suggests that GJIC plays a two-way role through propagating DNA damage effect between carcinoma to normal cells and reversing the bystander signaling, also called 'rescue effect' from bystander cells to irradiated cells, to enhance the DSB repair in targeted cells.

DOSE-RATE AND CELL-KILLING SENSITIVITY OF HIGH-LINEAR ENERGY TRANSFER ION BEAM

It is believed that the dose-rate of radiation will have an influence on cell sensitivity. The dose-rate effects on cell survival can be expressed by the change of the β term in the linear quadratic model. The value at a high-dose-rate decreases below 60 Gy/h and reaches zero at 0.2 Gy/h or less for photons. However, the effect for a high-LET ion-beam is not well known. At HIMAC, cells were exposed to 70 keV/μm carbon-ion beams at different dose-rates between 0.5 and 600 Gy/h at room temperature. The β values for all survival curves show no significant differences among the dose-rates tested for HSG, V79 and CHO cells. Changing the ion-beam dose-rate had no effect on cell survival. This suggests that high-LET particle beams, such as galactic cosmic rays, may not exhibit a dose-rate effect on cell survival. Low-dose-rate radiation showed an effect similar to high-dose-rate radiation.

Impact of pelvic incidence on change in lumbo-pelvic sagittal alignment between sitting and standing positions

PURPOSE

Lumbo-pelvic sagittal alignment is affected by pelvic incidence (PI), and the PI represents the compensatory capacity of lumbo-pelvic sagittal alignment. The purpose of this study was to analyze changes in lumbo-pelvic sagittal alignment between the standing and sitting positions and to analyze its association with PI.

METHODS

This study included 253 subjects (160 men and 93 women; age 53.6 ± 7.4 years). The subjects were divided into three groups (younger age group (YG), from 20 to 49 years; middle age group, from 50 to 69 years, and older age group (OG), of 70 years and above). Lumbar lordotic angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), and the associations between the changes in LL (∆LL), SS (∆SS), PT (∆PT), and PI were analyzed.

RESULTS

In the YG, the amount of change in LL, SS, and PT was larger than in the OG. These parameters correlated with age in the standing position but not in the sitting position. On the other hand, in all groups, there were positive correlations between PI and changes between the standing and sitting positions. Multiple logistic regression analysis demonstrated that ∆LL = 3.81 - 0.72 × PT + 0.52 × PI, ∆SS = - 4.50 - 5.3 × PT + 0.34 × PI, and ∆PT = - 9.1 + 3.5 × PT - 0.21 × PI.

CONCLUSIONS

Change in lumbo-pelvic parameters between the sitting and standing positions correlated with PI. These slides can be retrieved under Electronic Supplementary Material.

Postoperative Radiographic Early-Onset Adjacent Segment Degeneration after Single-Level L4-L5 Posterior Lumbar Interbody Fusion in Patients without Preoperative Severe Sagittal Spinal Imbalance

Study Design

Retrospective study.

Purpose

To investigate the relationship between preoperative total spinal sagittal alignment and the early onset of adjacent segment degeneration (ASD) after single-level posterior lumbar interbody fusion (PLIF) in patients with normal sagittal spinal alignment.

Overview of Literature

Postoperative early-onset ASD is one of the complications after L4–L5 PLIF, a common surgical procedure for lumbar degenerative disease in patents without severe sagittal imbalance. A better understanding of the preoperative characteristics of total spinal sagittal alignment associated with early-onset ASD could help prevent the condition.

Methods

The study included 70 consecutive patients diagnosed with lumbar degenerative disease who underwent single-level L4–L5 PLIF between 2011 and 2015. They were divided into two groups based on the radiographic progression of L3–L4 degeneration after 1-year follow-up: the ASD and the non-ASD (NASD) group. The following radiographic parameters were preoperatively and postoperatively measured: sagittal vertebral axis (SVA), thoracic kyphosis (TK), lumbar lordosis, pelvic tilt, and pelvic incidence (PI).

Results

Eight of the 70 patients (11%) experienced ASD after PLIF (three males and five females; age, 64.4±7.7 years). The NASD group comprised 20 males and 42 females (age, 67.7±9.3 years). Six patients of the ASD group showed decreased L3–L4 disc height, one had L3–L4 local kyphosis, and one showed both changes. Preoperative SVA, PI, and TK were significantly smaller in the ASD group than in the NASD group (p <0.05).

Conclusions

A preoperative small SVA and TK with small PI were the characteristic alignments for the risk of early-onset ASD in patients without preoperative severe sagittal spinal imbalance undergoing L4–L5 single-level PLIF.

Cervical Kyphotic Deformity after Laminoplasty in Patients with Cervical Ossification of Posterior Longitudinal Ligament with Normal Sagittal Spinal Alignment

Background

Preoperative cervico-thoracic kyphosis and cervical regional positive imbalance are the risk factors for postoperative cervical kyphosis after expansive laminoplasty (ELAP). However, the relationship between preoperative global sagittal spinal alignment and postoperative cervical kyphosis in patients with cervical ossification of the posterior longitudinal ligament (OPLL) is unclear. The purpose of this study was to investigate the relationship between the onset of postoperative cervical kyphosis after ELAP and the preoperative global spinal sagittal alignment in patients with OPLL with normal sagittal spinal alignment.

Methods

Sixty-nine consecutive patients without preoperative cervical kyphosis who underwent ELAP for OPLL and cervical spondylotic myelopathy (CSM) were enrolled. The global sagittal alignment radiography preoperatively and 1 year postoperatively were examined. The subjects were divided into a postoperative cervical lordosis group (LG) or a kyphosis group (KG) at 1 year postoperatively. The preoperative global sagittal spinal alignment between LG and KG in CSM and OPLL was compared.

Results

The occurrence of cervical kyphosis after ELAP was 7 of 27 cases (25.9%) in OPLL and 13 of 42 cases (31.0%) in CSM. In patients with CSM in the KG, C7 the sagittal vertical axis (SVA) was smaller than in the LG. In patients with cervical OPLL in the KG, C2-C7 angle, C2-C7 SVA, and thoracic kyphosis (TK) were smaller than those in the LG. In OPLL, the age of the KG was younger than that of LG; however, this was not a significant difference in CSM.

Conclusion

In patients with cervical OPLL without preoperative global spinal sagittal imbalance, preoperative small C2-C7 angle, C2-C7 SVA, TK, and younger age were typical characteristics of postoperative cervical kyphosis after ELAP.

Radiographic Assessment of Spinopelvic Sagittal Alignment from Sitting to Standing Position

Introduction

Most people in modern societies spend the majority of their time sitting. However, sagittal spinal alignment is usually analyzed in the standing position. For understanding the symptoms associated with postural changes, this alignment is better to be analyzed in various positions. The purpose of this study was to investigate lumbo-pelvic relationships between standing up and sitting (sit-to-stand) motion.

Methods

The study subjects were 25 healthy young adult volunteers without any spinal symptoms. The following parameters were measured, namely, intervertebral range of motion (IV ROM), lumbar lordotic angle (L1L5), sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI), on lateral whole-spine radiographs while sitting upright, sitting anterior flexed (anteflexed), standing anteflexed, and standing upright.

Results

The measurements of spinopelvic parameters during sit-to-stand motion (sitting upright, sitting anteflexed, standing anteflexed, standing upright, respectively) were as follows: L1L5 (7.9, −4.4, 3.1, 31.9) and PT (31.5, 26.5, 11.9, 7.7). Regarding IV ROM, the lumbar segmental ROM after seat-off was wider than before seat-off (sitting anteflexed). In particular, the L4-L5 segments had a wide ROM from standing anteflexed to standing upright.

Conclusions

The pelvis was retroverted in the sitting upright position and gradually anteverted during sit-to-stand motion. Lumbar lordosis decreased in the sitting upright position, temporarily decreased further (sitting anteflexed), and then increased in the standing position (standing anteflexed and standing upright). The mechanical loads on lumbosacral segments were greater after seat-off due to the reverse movement between upper lumbar and pelvic segments.

Randomized clinical trial of 24 versus 72 h antimicrobial prophylaxis in patients undergoing open total gastrectomy for gastric cancer

BACKGROUND

Open total gastrectomy carries a high risk of surgical-site infection (SSI). This study evaluated the non-inferiority of antimicrobial prophylaxis for 24 compared with 72 h after open total gastrectomy.

METHODS

An open-label, randomized, non-inferiority study was conducted at 57 institutions in Japan. Eligible patients were those who underwent open total gastrectomy for gastric cancer. Patients were assigned randomly to continued use of β-lactamase inhibitor for either 24 or 72 h after surgery. The primary endpoint was the incidence of SSI, with non-inferiority based on a margin of 9 percentage points and a 90 per cent c.i. The secondary endpoint was the incidence of remote infection.

RESULTS

A total of 464 patients (24 h prophylaxis, 228; 72 h prophylaxis, 236) were analysed. SSI occurred in 20 patients (8·8 per cent) in the 24-h prophylaxis group and 26 (11·0 per cent) in the 72-h group (absolute difference -2·2 (90 per cent c.i. -6·8 to 2·4) per cent; P < 0·001 for non-inferiority). However, the incidence of remote infection was significantly higher in the 24-h prophylaxis group.

CONCLUSION

Antimicrobial prophylaxis for 24 h after total gastrectomy is not inferior to 72 h prophylaxis for prevention of SSI. Shortened antimicrobial prophylaxis might increase the incidence of remote infection. Registration number: UMIN000001062 ( http://www.umin.ac.jp).

Spatial regularity of InAs-GaAs quantum dots: quantifying the dependence of lateral ordering on growth rate

The lateral ordering of arrays of self-assembled InAs-GaAs quantum dots (QDs) has been quantified as a function of growth rate, using the Hopkins-Skellam index (HSI). Coherent QD arrays have a spatial distribution which is neither random nor ordered, but intermediate. The lateral ordering improves as the growth rate is increased and can be explained by more spatially regular nucleation as the QD density increases. By contrast, large and irregular 3D islands are distributed randomly on the surface. This is consistent with a random selection of the mature QDs relaxing by dislocation nucleation at a later stage in the growth, independently of each QD’s surroundings. In addition we explore the statistical variability of the HSI as a function of the number N of spatial points analysed, and we recommend N > 10³ to reliably distinguish random from ordered arrays.

Randomized clinical trial of oral and intravenous versus intravenous antibiotic prophylaxis for laparoscopic colorectal resection

Background

The use of oral prophylactic antibiotics for the prevention of surgical-site infection (SSI) in patients undergoing laparoscopic surgery for colorectal cancer is controversial. The aim of this RCT was to evaluate whether intravenous perioperative antibiotics are inferior to combined preoperative oral and perioperative intravenous antibiotics in this setting.

Methods

Patients undergoing elective laparoscopic colorectal resection in a single cancer centre were assigned randomly to combined preoperative oral antibiotics (metronidazole and kanamycin) and perioperative intravenous antibiotics (cefmetazole) (oral/IV group) or to perioperative intravenous antibiotics (cefmetazole) alone (IV-only group). Patients were stratified for the analyses based on type of operation (colonic surgery, anterior resection or abdominoperineal resection), preoperative use of mechanical bowel preparation, preoperative chemoradiotherapy and the presence of diabetes mellitus. The primary endpoint was the overall rate of SSI. Secondary endpoints were the rates of incisional site infection, organ/space infection, anastomotic leakage, intra-abdominal abscess, adverse events and postoperative complications.

Results

Of 540 patients offered participation in the trial in 2013–2014, 515 agreed to take part and were randomized. Some 256 patients in the IV-only group and 255 in the oral/IV group completed the treatment per protocol. The overall rate of SSI was 7·8 per cent (20 of 256) in the IV-only group and 7·8 per cent (20 of 255) in the oral/IV group, confirming that perioperative administration of intravenous antibiotics alone was not inferior to the combined regimen (P = 0·017). There were no differences in rates of incisional site infection (5·5 versus 5·9 per cent respectively), organ/space infection (2·3 versus 2·0 per cent) or other secondary endpoints between the two groups.

Conclusion

Intravenous perioperative antimicrobial prophylaxis alone is not inferior to combined preoperative oral and intravenous perioperative prophylaxis with regard to SSI in patients with colorectal cancer undergoing elective laparoscopic resection. Registration number: UMIN000019339 (http://www.umin.ac.jp/ctr/).

Laparoscopic salvage lateral pelvic lymph node dissection for locally recurrent rectal cancer

AIM

The lateral pelvic lymph nodes are one of the major sites and sources of local recurrence (LR) after surgery for rectal cancer. Salvage lateral pelvic lymph node dissection (LPLD) is potentially curative, but the value of laparoscopic surgery in such cases is unknown. Our aim was to report the technical details of laparoscopic salvage LPLD for LR at these nodes after rectal cancer surgery.

METHOD

The study was based on nine patients who underwent laparoscopic salvage LPLD for LR at the lateral pelvic lymph nodes after surgery for rectal cancer. The safety and feasibility of this procedure were determined.

RESULTS

The median operation time was 381 min and the median estimated blood loss was 130 ml. There were no conversions. Adjacent structures removed en bloc were the pelvic plexus in four patients, the internal iliac artery in seven patients and the seminal vesicle in one patient. The median number of metastatic lymph nodes was 1 (range 1-11).

CONCLUSION

Our novel technique of laparoscopic salvage LPLD for LR at the lateral pelvic lymph nodes is safe and feasible.

Bystander effect between zebrafish embryos in vivo induced by high-dose X-rays

We employed embryos of the zebrafish, Danio rerio, for our studies on the in vivo bystander effect between embryos irradiated with high-dose X-rays and naive unirradiated embryos. The effects on the naive whole embryos were studied through quantification of apoptotic signals at 25 h post fertilization (hpf) through the terminal dUTP transferase-mediated nick end-labeling (TUNEL) assay followed by counting the stained cells under a microscope. We report data showing that embryos at 5 hpf subjected to a 4-Gy X-ray irradiation could release a stress signal into the medium, which could induce a bystander effect in partnered naive embryos sharing the same medium. We further demonstrated that this bystander effect (induced through partnering) could be successfully suppressed through the addition of the nitric oxide (NO) scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) into the medium but not through the addition of the CO liberator tricarbonylchloro(glycinato)ruthenium(II) (CORM-3). This shows that NO was involved in the bystander response between zebrafish embryos induced through X-ray irradiation. We also report data showing that the bystander effect could be successfully induced in naive embryos by introducing them into the irradiated embryo conditioned medium (IECM) alone, i.e., without partnering with the irradiated embryos. The IECM was harvested from the medium that had conditioned the zebrafish embryos irradiated at 5 hpf with 4-Gy X-ray until the irradiated embryos developed into 29 hpf. NO released from the irradiated embryos was unlikely to be involved in the bystander effect induced through the IECM because of the short life of NO. We further revealed that this bystander effect (induced through IECM) was rapidly abolished through diluting the IECM by a factor of 2× or greater, which agreed with the proposal that the bystander effect was an on/off response with a threshold.