Liposomal bupivacaine versus conventional anesthetic or placebo for hemorrhoidectomy: a systematic review and meta-analysis

BACKGROUND

Liposome bupivacaine (LB) is a long-acting anesthetic to enhance postoperative analgesia. Studies evaluating the efficacy of the LB against an active comparator (bupivacaine or placebo) on acute postoperative pain control in hemorrhoidectomy procedures are few and heterogeneous. Therefore, we performed a systematic review and meta-analysis comparing LB's analgesic efficacy and side effects to conventional/placebo anesthetic in hemorrhoidectomy patients.

METHODS

We performed a systematic review and meta-analysis of randomised controlled trials investigating the use of LB after haemorrhoidectomy. We searched the literature published from the time of inception of the datasets to August 19, 2022. The electronic databases included English publications in Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, and Scopus.

RESULTS

A total of 338 patients who underwent a hemorrhoidectomy procedure enrolled in three randomized clinical trials were included. The overall mean age was 45.84 years (SD ± 11.43), and there was a male predominance (53.55% male). In total 194 patients (52.2%) received LB and 144 (47.8%) received either bupivacaine or placebo. Pain scores at 72 h in the LB (199, 266, and 300 mg) were significantly lower than in the bupivacaine HCl group (p = 0.002). Compared to the bupivacaine/placebo group, the time to first use of opioids in the LB group was significantly longer at LB 199 mg (11 h vs. 9 h), LB 266 mg (19 h vs. 9 h), and LB 300 mg (19 h vs. 8 h) (p < 0.05). Moreover, compared to the bupivacaine/epinephrine group, it was significantly lower in the LB 266 mg group (3.7 vs. 10.2 mg) and at LB 300 mg (13 vs. 33 mg) (p < 0.05). Finally, regarding adverse effects, the conventional anesthetic/placebo group reported more pain in bowel movement than LB groups (OR 2.60, 95% CI 1.31-5.16).

CONCLUSIONS

Comparing LB to conventional anesthetic/placebo anesthetic for hemorrhoidectomy, we found a statistically significant reduction in pain through 72 h, decreased opioid requirements, and delayed time to first opioid use. Moreover, the conventional anesthetic/placebo group reported more pain in bowel movement than LB groups.

Downstaging after preoperative chemoradiation for locally advanced rectal cancer is associated with better survival than pathologic stage 0-1 disease treated with upfront surgery

BACKGROUND AND OBJECTIVES

It is unknown how patients with locally advanced rectal cancer with significant response to preoperative radiotherapy/chemoradiotherapy fare relative to patients with true pathologic 0-1 disease undergoing upfront surgery. We aimed to determine whether survival is improved in locally advanced rectal cancer downstaged to pathologic stage 0-1 disease compared to true pathologic stage 0-1 tumors.

METHODS

A retrospective review of the National Cancer Database between 2004 and 2016 was conducted. Three groups were identified: (1) clinical stage 2-3 disease downstaged to pathologic stage 0-1 disease after radiotherapy, (2) clinical stage 2-3 disease not downstaged after radiotherapy, and (3) true pathologic 0-1 tumors undergoing upfront surgery. The primary endpoint was overall survival and was compared using Kaplan-Meier and multivariate Cox regression analyses.

RESULTS

The study population consisted of 59,884 patients. Of the 40,130 patients with locally advanced rectal cancer treated with preoperative radiation, 12,670 (31.5%) had significant downstaging (group 1), while 27,460 (68.4%) had no significant downstaging (group 2). A total of 19,754 had pathologic 0-1 disease treated with upfront resection (group 3). On Kaplan-Meier analysis, downstaged patients had significantly better overall survival compared to both non-downstaged and true pathologic stage 0-1 patients (median 156 vs. 99 and 136 months, respectively, p < 0.001). On multivariate analysis, downstaged patients had significantly better survival (HR 0.88, p < 0.001) compared to true pathologic 0-1 patients.

CONCLUSIONS

Locally advanced rectal cancer downstaged after preoperative radiotherapy has significantly better survival compared to true pathologic stage 0-1 disease treated with upfront surgery. Response to chemoradiotherapy likely identifies a subset of patients with a particularly good prognosis.

Reallocating desk workers' sitting time to standing or stepping: associations with work performance

BACKGROUND

Studies have suggested that sitting time at work may lead to underperformance but they may underestimate the benefits to desk workers' performance of reducing occupational sitting time without considering the relative effects of the specific activities replaced.

AIMS

To estimate differences in work performance (presenteeism, absenteeism and engagement) when occupational sitting time is reallocated to standing/stepping in desk workers.

METHODS

Data for middle-aged desk workers were from a Japan-wide online survey (n = 2228). Self-report proportion of occupational sitting and standing/stepping, work hours and work performance indicators, including absolute (ratings relating only to self) and relative (ratings of self, compared to others) presenteeism and absenteeism, and dimensions of work engagement, were collected. Partition and isotemporal substitution models were used to investigate the associations of occupational sitting and standing/stepping time with work performance, including their reallocation effects.

RESULTS

In partition models, longer occupational sitting time was associated with a lower absolute presenteeism score (i.e. less productivity), lower absolute absenteeism (i.e. longer-than-expected work hours), and lower engagement. Longer occupational standing/stepping time was associated with lower absolute absenteeism and more engagement. Isotemporal substitution models showed that each hour of occupational sitting reallocated to standing/stepping was favourably associated with overall work engagement (B = 0.087; 95% confidence interval 0.051, 0.122) and its dimensions (B ranged from 0.078 to 0.092), but was not associated with presenteeism or absenteeism.

CONCLUSIONS

These findings suggest that management support and practical initiatives to encourage desk workers to replace portions of their sitting time with standing/stepping may contribute to enhanced work engagement.

Incidence rate and histology of appendiceal neoplasms in complicated versus uncomplicated appendicitis: A meta-analysis and systematic review

INTRODUCTION

Studies evaluating the rate and histology of appendiceal neoplasms between complicated and uncomplicated appendicitis include a small number of patients. Therefore, we sought a meta-analysis and systematic review comparing the rates and types of appendiceal neoplasm between complicated and uncomplicated appendicitis.

METHODS

We included articles published from the time of inception of the datasets to September 30, 2022. The electronic databases included English publications in Ovid MEDLINE In-Process & Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, and Scopus.

RESULTS

A total of 4962 patients with appendicitis enrolled in 4 comparative studies were included. The mean age was 43.55 years (16- 94), and half were male (51%). Based on intra-operative findings, 1394 (38%) had complicated appendicitis, and 3558 (62%) had uncomplicated appendicitis. The overall incidence rate of neoplasm was 1.98%. No significant difference was found in the incidence rate of appendiceal neoplasm between complicated (3.29%) and uncomplicated (1.49%) appendicitis (OR 0.44, 95% CI 0.16- 1.23; p < 0.087; I2 = 54.9%). The most common appendiceal neoplasms were Neuroendocrine Tumors (NET) (49.21%), Nonmucinous Adenocarcinoma (24.24%), Mixed Adeno-Neuroendocrine Tumor (MANEC) (11.40%), Mucinous Adenocarcinoma (4.44%). There was a significant difference between complicated and uncomplicated appendicitis in rates of adenocarcinoma (50% vs. 13%), NET (31% vs. 74%), MANEC (19% vs. 13%) (P < 0.001).

CONCLUSION

While there was no significant difference in the overall neoplasm rate between complicated and uncomplicated appendicitis, the NET rate was significantly higher in uncomplicated appendicitis. In comparison, the Adenocarcinoma rate was considerably higher in Complicated appendicitis. These findings emphasize the importance of evaluating risk factors for neoplasm when considering appendectomy in patients with appendicitis.

Novel antibiotic irrigation device versus standard O-ring wound retractor in the prevention of surgical site infection following colorectal resection

PURPOSE

We sought to compare the effectiveness of a novel antibiotic irrigation device to the standard O-ring wound retractor in preventing surgical site infections (SSIs) following colorectal resections.

METHODS

This single-arm clinical trial included patients undergoing colorectal resections utilizing the novel device. A retrospective cohort of patients undergoing the same procedures with the O-ring retractor was selected as the control group. The primary outcome assessed was SSI. Secondary outcomes assessed were overall complications, hospital length of stay (LOS), and 30-day readmission. A univariable and multivariable logistic regression model was built to evaluate the association between SSI as the outcome variable and the use of the novel device as the main independent variable. The model was adjusted for any confounding variables.

RESULTS

Eighty-six novel device cases and 170 O-ring retractor cases were enrolled. There were no significant differences between the two groups in terms of demographics and preoperative comorbidities. Cases with the novel device had fewer Pfannenstiel incisions (1.2% vs. 14.6%, p < 0.001). There were no other significant differences in intraoperative variables. SSI rates were significantly lower in the novel device group (1.2% vs. 9.1%, p = 0.014). There were no other significant differences in postoperative complications. Multivariable logistic regression with backward elimination showed that the use of the novel device was significantly more effective against SSI by 92.5% compared to the use of the O-ring retractor.

CONCLUSION

The novel device may contribute to lower SSI rates compared to the O-ring retractor following colorectal resection.

Robotic right versus left colectomy for colorectal neoplasia: a systemic review and meta-analysis

Previous studies comparing right and left colectomies have shown variable short-term outcomes. Despite the rapid adoption of robotics in colorectal operations, few studies have addressed outcome differences between robotic right (RRC) and left (RLC) colectomies. Therefore, we sought to compare the short-term outcomes of RRC and RLC for neoplasia. This is a systematic review and meta-analysis of articles published from the time of inception of the datasets to May 1, 2022. The electronic databases included English publications in Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE, Ovid EMBASE, and Scopus. A total of 13,514 patients with colon neoplasia enrolled in 9 comparative studies were included. The overall mean age was 64.1 years (standard deviation [SD] ± 9.8), and there was a minor female predominance (52% female vs. 48% male). 8656 (64.0%) underwent RRC and 4858 (36.0%) underwent RLC. The ASA score 1 of - 2 in the LRC group was 37% vs. 21% in the R. Whereas the ASA score 3-4 was 62% in the LRC vs. 76% in RRC. Moreover, the mean of the Charlson Comorbidity Score in the LRC was 4.3 (SD 1.9) vs. 3.1 (SD 2.3) in the RRC. Meta-analysis revealed a significantly higher rate of ileus in RRC (10%) compared to RLC (7%) (OR 1.46, 95% CI 1.27-1.67). Additionally, operative time was significantly shorter by 22.6 min in RRC versus LRC (95% CI - 37.4-7.8; p < 0.001). There were no statistically significant differences between RRC and RLC in conversion to open operation, estimated blood loss, wound infection, anastomotic leak, reoperation, readmission, and hospital length of stay. In this only meta-analysis comparing RRC and LRC for colon neoplasia, we found that RRC was independently associated with a shorter operative time but increased risk of ileus.

Does coffee affect bowel recovery following minimally invasive colorectal operations? A three-armed randomized controlled trial

PURPOSE

Previous studies have suggested that coffee may shorten the postoperative ileus period. We sought to evaluate the impact of both coffee and caffeine on shortening the return of postoperative bowel function following minimally invasive colectomy.

METHODS

This was a single-center, randomized controlled clinical trial conducted in a tertiary hospital. Patients undergoing an elective robotic or laparoscopic small or large bowel operation were included in this study. Patients were randomized into one of three groups: warm water, decaffeinated coffee, and caffeinated coffee. Subjects were assigned to drink a 4-oz cup three times daily starting on postoperative day one. The primary endpoint was time to first bowel movement. Secondary endpoints included time to first flatus, length of hospital stay, and postoperative morbidity.

RESULTS

A total of 99 patients were included in this study: 31 warm water, 31 decaffeinated coffee, and 37 caffeinated coffee. The groups were similar in age and sex (p = 0.51 and 0.91, respectively). Mean (SD) time to the first bowel movement in days was 2.94 (1.4), 2.58 (1.2), and 2.86 (1.3), respectively (p = 0.53). There were no significant differences observed in postoperative morbidity (p = 0.52) between groups. Multivariate linear regression analysis did not reveal a statistically significant association between any interventions and time to first bowel movement or length of hospital stay.

CONCLUSIONS

Coffee (caffeinated or decaffeinated) does not expedite the return of bowel function following minimally invasive operation.

TRIAL REGISTRATION

https://classic.

CLINICALTRIALS

gov/ct2/show/NCT02639728 NCT02639728.

Hartmann's Reversal is More Complex Than Elective Left Colectomy

BACKGROUND

Hartmann's reversal (HR) is associated with significant technical complexity and morbidity. The decision to perform HR is difficult and up to 50% of patients with colostomies do not undergo a reversal. To better guide surgeons and patients with this decision, we sought to assess the surgical risks and outcomes of HR as compared to elective left colectomy (LC).

METHODS

We conducted a retrospective analysis of a prospective database at a tertiary medical center. Patients undergoing elective Hartmann's reversal and left colectomy between January 2014 and November 2021 were identified. We compared preoperative variables, intraoperative events, and short-term postoperative outcomes.

RESULTS

135 patients were identified: 30 HR and 105 LC. There were no significant differences in demographics or preoperative comorbidities between HR and LC. There were more open and fewer robotic cases in HR (23.3% vs 2.9%, P < .0001; 46.6% vs 76.0%, P < .01). Total operative time was significantly longer in HR than LC (261.8 vs 211.7 minutes, P = .02). There was a significantly higher percentage of intraoperative complications in HR (13.3% vs 1.9%, P < .01). There was a significantly higher rate of minor postoperative complications in HR than LC (46.7% vs 26.7%, P = .04), but not major (6.7% vs 5.8%, P = .85). Time to first flatus/bowel movement was significantly longer in HR than LC (3.6 vs 2.5 days, P < .001).

CONCLUSION

Hartmann's reversal is a more technically challenging operation than elective left colectomy and is associated with significantly higher rates of intraoperative and minor postoperative complications. Future studies should focus on mitigating these risk factors to optimize patient outcomes.

Bilateral Gluteal Fasciocutaneous Advancement Flaps With and Without Tie-Over Sutures in Treatment of Chronic Pilonidal Disease: A Prospective Case Series

PURPOSE

Flap procedures following pilonidal excision have high recurrence and dehiscence rates. We present a cosmetic, outpatient technique to reconstruction via bilateral gluteal fasciocutaneous advancement flaps with and without tie-over sutures.

METHODS

This is a prospective case series of 51 patients (40 males and 11 females). Following elliptical excision of pilonidal disease, gluteal fasciocutaneous advancement flaps were elevated circumferentially using blunt, discontinuous dissection, and a multilayered closure was performed. The resulting scar was midline. Thirty-five patients (68.6%) also had two full-thickness, compressing sutures tied over rolled up gauze.

RESULTS

Patients had a mean age of 28.2 and body mass index of 26.8. Eight (15.9%) were smokers and 11 (21.6%) were obese. At a mean follow-up of 38.7 months, there were no recurrences and 19 (37.3%) patients had wound dehiscence. There was no significant difference in dehiscence between patients with and without tie-over sutures (31.4% vs 50%, P = 0.20). There was no significant difference in dehiscence between smokers and non-smokers, (62.5% vs 41.9%, P = 0.47), or between obese and non-obese patients (36.4% vs 46.3%, P = 0.51). Obese patients with tie-over sutures had significantly less dehiscence compared to obese patients without tie-over sutures (14% vs 75%, P = 0.03).

CONCLUSION

Bilateral gluteal fasciocutaneous advancement flap with consideration of tie-over sutures is an outpatient treatment for chronic pilonidal disease with resultant midline scar and with no recurrence in our series.

Robotic colorectal procedures: does operative start time impact short-term outcome?

BACKGROUND

Previous publications revealed more complications in afternoon versus morning surgeries. With much attention given to robotic surgery outcomes, we sought to evaluate whether morning versus afternoon start time matters.

METHODS

In a retrospective review of a prospective database, 210 robotic colorectal surgeries were grouped into 97 morning versus 113 afternoon cases. Preoperative risk factors, intraoperative events, and 30-day postoperative outcomes were compared. An independent samples t-test, Fisher's exact test, and linear regression were used for categorical and continuous variables.

RESULTS

Morning patients were significantly younger than afternoon patients (59.5 vs. 65.5, p = 0.004), but there were no significant differences in gender, mean BMI, Charlson Comorbidity Index score, total operative time, console time, estimated blood loss, indications for surgery, and resection type. Morning patients had a significantly shorter mean length of stay (6.0 vs. 8.0 days, p = 0.021), but no significant differences in overall postoperative complications (0.30 vs. 0.30, p = 0.715), wound infection (5.2% vs. 7.1%, p = 0.564), anastomotic leak (0% vs. 2.7%, p = 0.251), ileus/small bowel obstruction (29.9% vs. 22.1%, p = 0.199), and 30-day readmission (8.2% vs. 7.1%, p = 1.000). When analyzing time of day as a continuous variable, we found no significant associations with intra- or postoperative complications.

CONCLUSION

We found no correlation between surgery start time and intra- or postoperative outcomes. This can be partly attributed to these cases being non-emergent and performed primarily by two experienced surgeons with highly trained operating room robotic staff in a large volume tertiary center. This, along with decreased fatigue attributed to superior ergonomics of robotic surgery, may have mitigated previously reported differences between morning and afternoon procedures.

Minimally invasive right versus left colectomy for cancer: does robotic surgery mitigate differences in short-term outcomes?

Studies comparing right (RC) and left colectomies (LC) show higher rates of ileus in RC and higher wound infection and anastomotic leak rates in LC. However, prior studies did not include robotic procedures. We compared short-term outcomes of laparoscopic and robotic RC and LC for cancer, with sub-analysis of robotic procedures. In a retrospective review of a prospective database, preoperative factors, intraoperative events, and 30-day postoperative outcomes were compared. Student's t tests and Chi-square tests were used for continuous and categorical variables, respectively. A logistic binomial regression was performed to assess whether type of surgery was associated with postoperative complications. Between January 2014 and August 2020, 115 patients underwent minimally invasive RC or LC for cancer. Sixty-eight RC [30 (44.1%) laparoscopic, 38 (55.9%) robotic] and 47 LC [13 (27.6%) laparoscopic, 34 (72.4%) robotic] cases were included. On univariate analysis, RC patients had significantly higher overall postoperative complications but no differences in rates of ileus/small bowel obstruction, wound infection, time to first flatus/bowel movement, length of hospital stay, and 30-day readmissions. On multivariate analysis, there was no significant difference in overall complications and laparoscopic surgery had a 2.5 times higher likelihood of complications than robotic surgery. In sub-analysis of robotic cases, there was no significant difference among all outcome variables. Previously reported outcome differences between laparoscopic RC and LC for cancer may be mitigated by robotic surgery.

Predictors of lymph node metastases in patients with malignant adenomatous polyps of the colon

BACKGROUND

We sought to describe predictors of lymph node positivity in patients with malignant colon polyps to identify low risk patients who may potentially avoid radical surgery.

DESIGN

The National Cancer Database (2010-2015) was queried for all patients with malignant colonic polyps who underwent formal colonic resection. Univariate and multivariate methods were used to determine independent predictors of lymph node metastasis.

RESULTS

14,663 patients were identified. Lymph node disease was present in 9% of patients. High-grade disease, LVI, PNI, younger age, and left sided location were univariate predictors of lymph node disease. High-grade disease (OR 1.84), left sided location (OR 1.31), LVI (OR 5.79), and PNI (OR 1.70) were independent predictors, while elderly age (OR 0.64) was protective (all p-values <0.001). Elderly patients with low grade disease of the right/transverse colon without LVI/PNI had a 4.4% risk of lymph node disease. High grade, left-sided tumors with LVI, non-elderly age, had a 30% risk.

CONCLUSION

Non-elderly age, left-sided location, LVI, PNI and high-grade histology are independent predictors of lymph node metastasis in malignant colonic polyps.

P932Structural changes in left ventricle after transcatheter aortic valve implantation

Background

Transcatheter aortic valve implantation (TAVI) has improved prognosis and quality of life of patients with severe aortic stenosis (AS) who had been considered inoperable or at high risk for surgical aortic valve replacement reflecting their age, frailty, and comorbidities. However, less is known about changes in cardiac geometry after TAVI procedure, and predictors of them.

Purpose

To clarify changes in cardiac geometry after TAVI, and their predictors.

Methods

We retrospectively analyzed patients with severe AS who underwent TAVI in our institute between May 2016 and June 2018. Of the 117 consecutive patients enrolled to this study, 12 patients died before six-month follow up, and finally 88 patients received follow up exams including echocardiography at six months after TAVI procedure.

Results

The analysis of echocardiographic data at the baseline and the six-month follow up of the 88 patients (age 86.2±4.0 years, male 19.3%, STS-PROM 6.76±3.28%, peak aortic jet velocity 4.67±0.75m/s) revealed that left ventricular end-diastolic volume index (LVEDVi) (from 80.1±20.9ml/m2to 74.2±15.9ml/m2, p=0.011), and left ventricular mass index (LVMi) (from 116.0±32.7g/m2to 93.6±25.6g/m2, p<0.001) had improved in six months after TAVI procedure. The difference of LVEDVi (ΔLVEDVi: six-month LVEDVi–baseline LVEDVi) and the difference of LVMi (ΔLVMi: six-month LVMi – baseline LVMi) were significantly higher in the patients with chronic atrial fibrillation compared to the rest (ΔLVEDVi: +7.7±8.7ml/m2 vs −7.2±18.1ml/m2, p=0.024; ΔLVMi: +7.1±11.5g/m2 vs −25.3±33.5g/m2, p=0.008). In echocardiographic data, ΔLVEDVi and ΔLVMi both had positive correlation between baseline E/e' ratio (ΔLVEDVi: r=0.224, p=0.048; ΔLVMi: r=0.240, p=0.034), and negative correlation between baseline LVEDVi (ΔLVEDVi: r=−0.674, p<0.001; ΔLVMi: r=−0.312, p=0.003), LVMi (ΔLVEDVi: r=−0.422, p<0.001; ΔLVMi: r=−0.699, p<0.001), peak aortic jet velocity (ΔLVEDVi: r=−0.257, p=0.016; ΔLVMi: r=−0.376, p<0.001), and mean transaortic pressure gradient (ΔLVEDVi: r=−0.269, p=0.011; ΔLVMi: r=−0.403, p<0.001).

Conclusion

TAVI resulted in reverse remodeling and regression of hypertrophy in left ventricle. And these improvement were grater in patients with more advanced left ventricular remodeling and hypertrophy, and higher severity of AS at the baseline, however, less in patients with chronic atrial fibrillation and worse diastolic dysfunction.

Cartilage wear patterns in severe osteoarthritis of the trapeziometacarpal joint: a quantitative analysis

OBJECTIVE

The present quantitative study aimed to assess the three-dimensional (3-D) cartilage wear patterns of the first metacarpal and trapezium in the advanced stage of osteoarthritis (OA) and compare cartilage measurements with radiographic severity.

DESIGN

Using 19 cadaveric trapeziometacarpal (TMC) joints, 3-D cartilage surface models of the first metacarpal and trapezium were created with a laser scanner, and 3-D bone surface model counterparts were similarly created after dissolving the cartilage. These two models were superimposed, and the interval distance on the articular surface as the cartilage thickness was measured. All measurements were obtained in categorized anatomic regions on the articular surface of the respective bone, and we analyzed the 3-D wear patterns on the entire cartilage surface. Furthermore, we compared measurements of cartilage thickness with radiographic OA severity according to the Eaton grading system using Pearson correlation coefficients (r).

RESULTS

In the first metacarpal, the cartilage thickness declined volarly (the mean cartilage thickness of the volar region was 0.32 ± 0.16 mm, whereas that of the dorsal region was 0.53 ± 0.18 mm). Conversely, the cartilage evenly degenerated throughout the articular surface of the trapezium. Measurements of the categorized regions where cartilage thinning was remarkable exhibited statistical correlations with radiographic staging (r = -0.48 to -0.72).

CONCLUSIONS

Our findings indicate that cartilage wear patterns differ between the first metacarpal and trapezium in the late stage of OA. There is a need for further studies on cartilage degeneration leading to symptomatic OA in the TMC joint.

X-Ray Spectrometer for EXAFS Using a Position Sensitive Detector

An active recording x-ray crystal spectrometer for extended x-ray absorption fine structure (EXAFS) has been built using a position sensitive detector of the self scanning photodiode array (SSPA) type. The SSPA detector has energy and position sensitivity for x-rays. The spectrometer was applied to the measurement for EXAFS of the several compounds in foil, powder and liquid states. The spectra can be obtained rapidly, and compare very well with other methods. We found that the SSPA detector is very useful for the measurement of EXAFS.

Probing ultrafast spin-relaxation and precession dynamics in a cuprate Mott insulator with seven-femtosecond optical pulses

A charge excitation in a two-dimensional Mott insulator is strongly coupled with the surrounding spins, which is observed as magnetic-polaron formations of doped carriers and a magnon sideband in the Mott-gap transition spectrum. However, the dynamics related to the spin sector are difficult to measure. Here, we show that pump-probe reflection spectroscopy with seven-femtosecond laser pulses can detect the optically induced spin dynamics in Nd2CuO4, a typical cuprate Mott insulator. The bleaching signal at the Mott-gap transition is enhanced at ~18 fs. This time constant is attributable to the spin-relaxation time during magnetic-polaron formation, which is characterized by the exchange interaction. More importantly, ultrafast coherent oscillations appear in the time evolution of the reflectivity changes, and their frequencies (1400-2700 cm-1) are equal to the probe energy measured from the Mott-gap transition peak. These oscillations can be interpreted as the interference between charge excitations with two magnons originating from charge-spin coupling.

Educational effects using a robot patient simulation system for development of clinical attitude

INTRODUCTION

The aim of this study was to assess the effectiveness of improving the attitude of dental students towards the use of a full-body patient simulation system (SIMROID) compared to the traditional mannequin (CLINSIM) for dental clinical education.

MATERIALS AND METHODS

The participants were 10 male undergraduate dental students who had finished clinical training in the university hospital 1 year before this study started. They performed a crown preparation on an upper pre-molar tooth using SIMROID and CLINSIM as the practical clinical trials. The elapsed time for preparation was recorded. The taper of the abutment teeth was measured using a 3-dimensional shape-measuring device after this trial. In addition, a self-reported questionnaire was collected that included physical pain, treatment safety and maintaining a clean area for each simulator. Qualitative data analysis of a free format report about SIMROID was performed using text mining analysis. This trial was performed twice at 1-month intervals.

RESULTS

The students considered physical pain, treatment safety and a clean area for SIMROID significantly better than that for CLINSIM (P < .01). The elapsed time of preparation in the second practical clinical trial was significantly lower than in the first for SIMROID and CLINSIM (P < .01). However, there were no significant differences between the abutment tapers for both systems. For the text mining analysis, most of the students wrote that SIMROID was similar to real patients.

CONCLUSION

The use of SIMROID was proven to be effective in improving the attitude of students towards patients, thereby giving importance to considerations for actual patients during dental treatment.

Altered bone density and stress distribution patterns in long-standing cubitus varus deformity and their effect during early osteoarthritis of the elbow

OBJECTIVE

To quantify the bone density and stress distribution patterns in long-standing cubitus varus and clarify the effects of the deformity on bone density.

DESIGN

We created three-dimensional computed tomography (CT) elbow models from 21 patients with long-standing cubitus varus deformities without advanced osteoarthritis (OA) and assessed the deformity by superimposing the affected humerus onto a mirror-image of the contralateral normal. Elbows were divided into 13 regions before measuring the bone density of each region and comparing the percentage of high-density volume (%HDV) between affected and normal sides. We constructed finite element models and quantitatively analyzed stress distribution.

RESULTS

Average degrees of deformities were 20.1° of varus, 6.4° of extension, and 12.7° of internal rotation. The medial side of the affected humerus and ulna, Anteromedial trochlea (P < 0.001), Medial coronoid (P = 0.004), and Medial olecranon (P = 0.049) had significantly higher %HDVs than their normal counterparts. Conversely, %HDVs on the affected lateral side, Capitellum (P < 0.001), Anterolateral trochlea (P = 0.010), Posterolateral trochlea (P < 0.001), Lateral coronoid (P = 0.007), and Lateral olecranon (P < 0.001) were significantly lower than the normal side. The affected radial head %HDVs at Anterolateral and Posteromedial quadrants were high (P = 0.007) and low (P = 0.007), respectively. The bone density distribution coincided with stress distribution patterns revealed by finite element analysis (FEA), except in the lateral region influenced by forearm rotation.

CONCLUSIONS

Repetitive stress on the medial elbow may alter bone density distribution patterns, probably presenting from early stage of OA.

Accuracy of self-reported height, weight and waist circumference in a Japanese sample

Objective

Inconsistent results have been found in prior studies investigating the accuracy of self‐reported waist circumference, and no study has investigated the validity of self‐reported waist circumference among Japanese individuals. This study used the diagnostic standard of metabolic syndrome to assess the accuracy of individual's self‐reported height, weight and waist circumference in a Japanese sample.

Methods

Study participants included 7,443 Japanese men and women aged 35–79 years. They participated in a cohort study's baseline survey between 2007 and 2011. Participants' height, weight and waist circumference were measured, and their body mass index was calculated. Self‐reported values were collected through a questionnaire before the examination.

Results

Strong correlations between measured and self‐reported values for height, weight and body mass index were detected. The correlation was lowest for waist circumference (men, 0.87; women, 0.73). Men significantly overestimated their waist circumference (mean difference, 0.8 cm), whereas women significantly underestimated theirs (mean difference, 5.1 cm). The sensitivity of self‐reported waist circumference using the cut‐off value of metabolic syndrome was 0.83 for men and 0.57 for women.

Conclusions

Due to systematic and random errors, the accuracy of self‐reported waist circumference was low. Therefore, waist circumference should be measured without relying on self‐reported values, particularly in the case of women.

Abstract OT3-07-02: Influence of exercise or educational programs on long-term physical activity by patients after surgery for primary breast cancer: A randomized trial

[Background]

Past studies revealed that a moderate to high level of physical activity after diagnosis of breast cancer reduces both the risk of breast cancer-related death and death from all causes. Furthermore, some randomized studies suggested that exercise programs improve the percentage of patients who complete the chemotherapy and quality of life, and decrease fatigue, and adverse events. The issues to be determined include defining an established uniform exercise program and the efficacy of a long-term exercise program after breast cancer surgery.

[Object] To elucidate the efficacy of a long-term exercise program and to verify the safety and feasibility of a uniform exercise program using an ‘existing social resource’ after primary therapy of breast cancer.

[Design] A multi-center, randomized trial.

[Method] Subjects: The subjects included patients who had completed treatment for primary breast cancer, including surgery and/or adjuvant chemotherapy. Patients with metastatic breast cancer were excluded.

Randomization & intervention: The patients were randomly assigned to three groups.

The first group followed an exercise program at Curves® that involved 30 minutes of exercise, including aerobics, weight training, and stretching 3 times a week for 4 months. The second group was given life-style guidance at least once that patients participate in a lecture program about recommended exercise at this point and the importance of weight control after diagnosis of breast cancer using a brochure. The third group served as controls that the patients receive a brochure used same one in the second group. The variables included age and weight.

Outcome: The primary endpoint is level of physical activity at 1 year after randomization, and the secondary endpoints are the percentage of those completing the exercise program, patient reported outcomes (QOL, cancer or treatment associated symptoms, fatigue, depression, and anxiety), body mass index, bone density, and level of lymphedema.

Period of research: The study will last 2 years beginning March 2016.

Sample size: We plan to enroll 400 patients to detect 20% difference with 90% power.

Additional study: Some biochemical markers in the blood will be evaluated to determine the mechanism of the effect of exercise on the human body.

Citation Format: Kawada K, Taira N, Hatono M, Takahashi Y, Miyoshi Y, Nogami T, Iwamoto T, Motoki T, Sien T, Matsuoka J, Doihara H, Ikeda M, Ogasawara Y, Takabatake D, Yoshitomi S, Kiyoto S, Yamamoto S, Mizota Y, Oka K. Influence of exercise or educational programs on long-term physical activity by patients after surgery for primary breast cancer: A randomized trial [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr OT3-07-02.

Picosecond rotation of a ring-shaped optical lattice by using a chirped vortex-pulse pair

A novel method of ultrafast rotation of a ring-shaped optical lattice in the picosecond time region was proposed and demonstrated. Our ring-lattice generator was assembled by a pair of linearly chirped pulses with a time delay, a high-order birefringent retarder, and an axially symmetric polarization element. Using a mode-locked Ti:sapphire laser oscillator as a light source, stable two-, four-, and six-petaled ring-lattice rotations were demonstrated with the rotation periods of 1.6, 3.2, and 4.8 ps, respectively. Our method has the potential to open up a new technique to resonantly excite propagating quasi-particles together with their coherent enhancement.

Safety assessment of the Clostridium butyricum MIYAIRI 588® probiotic strain including evaluation of antimicrobial sensitivity and presence of Clostridium toxin genes in vitro and teratogenicity in vivo

Probiotics are live microorganisms ingested for the purpose of conferring a health benefit on the host. Development of new probiotics includes the need for safety evaluations that should consider factors such as pathogenicity, infectivity, virulence factors, toxicity, and metabolic activity. Clostridium butyricum MIYAIRI 588® (CBM 588®), an anaerobic spore-forming bacterium, has been developed as a probiotic for use by humans and food animals. Safety studies of this probiotic strain have been conducted and include assessment of antimicrobial sensitivity, documentation of the lack of Clostridium toxin genes, and evaluation of CBM 588® on reproductive and developmental toxicity in a rodent model. With the exception of aminoglycosides, to which anaerobes are intrinsically resistant, CBM 588® showed sensitivity to all antibiotic classes important in human and animal therapeutics. In addition, analysis of the CBM 588® genome established the absence of genes for encoding for α, β, or ε toxins and botulin neurotoxins types A, B, E, or F. There were no deleterious reproductive and developmental effects observed in mice associated with the administration of CBM 588®. These data provide further support for the safety of CBM 588® for use as a probiotic in animals and humans.

How to Embolize Wide-Necked Aneurysms?

Novel endovascular approaches are needed for safer and more definitive treatment of wide-necked aneurysms, to overcome the limitations of the Guglielmi detachable coil (GDC) system and further, the application of this technique.

The double GDC technique (DGT), for embolization of wide-necked aneurysms, and the combination of stent placement and coil deposition (CTSC) for management of fusiform aneurysms have been developed and their usefulness is reviewed. The DGT involves scaffolding of a GDC coil to form a stabilizing frame inside the aneurysmal neck and then positioning of a second coil to reinforce the first coil. After confirming the absence of coil herniation in the parent artery, both coils are released together. A patient with a wide-necked large aneurysm of the left internal carotid artery was treated using this technique, and followed up angiographically and clinically for a period of three months. The follow-up angiograms revealed complete embolization of the aneurysm.

The patient had no neurological changes or adverse events during the procedure. The CTSC involves reconstructing the artery with a stent and packing the aneurysm lumen with GDCs through the stent interstices. A patient with a dissecting fusiform aneurysm of the vertebral artery associated with hypoplasia of the contralateral vertebral artery was treated using this technique to prevent rebleeding. His clinical course was uneventful over a six-month follow-up period. Angiography performed two months after the procedure confirmed excellent flow through the right vertebral artery and absence of filling of the daughter aneurysm.

Decreased expression of Met during differentiation in rat lung

Organ-specific stem cells play key roles in maintaining the epithelial cell layers of lung. Bronchioalveolar stem cells (BASCs) are distal lung epithelial stem cells of adult mice. Alveolar type 2 (AT2) cells have important functions and serve as progenitor cells of alveolar type 1 (AT1) cells to repair the epithelium when they are injured. Hepatocyte growth factor (HGF) elicits mitogenic, morphogenic, and anti-apoptotic effects on lung epithelial cells through tyrosine phosphorylation of Met receptor, and thus is recognized as a pulmotrophic factor. To understand which cells HGF targets in lung, we identified the cells expressing Met by immunofluorescence assay. Met was strongly expressed in BASCs, which expressed an AT2 cell marker, pro-SP-C, and a club cell marker, CCSP. In alveoli, we found higher expression of Met in primary AT2 than in AT1 cells, which was confirmed using primary AT2 cells. We further examined the mitogenic activity of HGF in AT2-cell-derived alveolar-like cysts (ALCs) in 3D culture. Multicellular ALCs expressed Met, and HGF enhanced the ALC production. Taking these findings together, BASCs could also be an important target for HGF, and HGF-Met signaling could function more potent on cells that have greater multipotency in adult lung.

A histological study on microthrombi in autopsy cases of DIC

Microthrombi in 43 untreated and 26 treated cases of DIC were studied histologically and immunohistochemically. In the untreated cases, four types of microthrombi (intraluminal microthrombi with or without fibroblastic and/or smooth muscle cell reaction) were identified. Microthrombi in the former three types showed various degrees of thrombolysis. Failure of thrombolysis seemed to lead the organization of microthrombi. These morphological findings were considered to indicate the course of DIC and the degree of disappearance of the microthrombi in DIC. Microthrombi in the hepatic sinusoids and glomerular capillaries were studied with special reference to the removal processes of the microthrombi. Pathogenesis of renal cortical necrosis in DIC was also discussed. The number of microthrombi was markedly decreased by heparin and gabexate mesilate treatment. The incidences of microthrombi in the liver, kidney, lung, and heart were compared in the two treated groups.

Immunohistochemical expression of fibrillin-1 and fibrillin-2 during tooth development

BACKGROUND AND OBJECTIVE

Oxytalan fibers are categorized as a microfibril assembly without elastin deposition, and are unique components in the periodontal ligament (PDL). However, little is known about their formation during PDL development. To clarify the mechanisms of oxytalan fiber formation in developing PDL, we performed immunohistochemical analysis to detect the direct expression of fibrillin-1 and fibrillin-2, which are major components of microfibrils.

MATERIAL AND METHODS

Frozen sections of lower molars from mice at several stages of growth were prepared without chemical fixation and decalcification using the film transfer method. Immunostaining was performed with anti-fibrillin-1 and -2, and anticytokeratin antibodies.

RESULTS

Fibrillin-1 was not expressed in the dental follicle during the crown forming stage. At postneonatal day 9, fibrillin-1 expression started with meshwork appearance between the epithelial cells from Hertwig's epithelial root sheath at the root dentin surface. Fibirillin-2 was detected much earlier than fibrillin-1 expression. Fibrillin-2 was expressed with a liner appearance, running parallel to the root axis in PDL, and was partially co-expressed with cytokeratin 14 expression in Hertwig's epithelial root sheath. Furthermore, we detected both fibrillin-1 and fibrillin-2 expression in human PDL. Fibrillin-1 was detected in fibers with a vertically oriented root axis in PDL. Fibrillin-2 was widely expressed in PDL, including around the epithelial cell rests of Malassez. Fibrillin-1 and fibrillin-2 were clearly co-expressed in thick fiber structures in human PDL.

CONCLUSION

Our results suggest that both fibrillin-1 and fibrillin-2 expression is required to form thick oxytalan fibers in PDL. Based on the expression patterns for fibrillin-1 and fibrillin-2, they have different functions during tooth root and PDL development. Early expression of fibrillin-2 may regulate dental epithelial cell behavior during root and PDL development.

Advanced functional polymers for regenerative and therapeutic dentistry

Use of ceramics and polymers continues to dominate clinical procedures in modern dentistry. Polymers have provided the basis for adhesives, tissue void fillers, and artificial replacements for whole teeth. They have been remarkably effective in the clinic at restoration of major dental functions after damage or loss of teeth. With the rapid development of polymer science, dental materials science has significantly lagged behind in harnessing these advanced polymer products. What they offer is new and unique properties superior to traditional polymers and crucially a range of properties that more closely match natural biomaterials. Therefore, we should pursue more vigorously the benefits of advanced polymers in dentistry. In this review, we highlight how the latest generation of advanced polymers will enhance the application of materials in the dental clinic using numerous promising examples. Polymers have a broad range of applications in modern dentistry. Some major applications are to construct frameworks that mimic the precise structure of tissues, to restore tooth organ function, and to deliver bioactive agents to influence cell behavior from the inside. The future of polymers in dentistry must include all these new enhancements to increase biological and clinical effectiveness beyond what can be achieved with traditional biomaterials.

Identification of oscillatory firing neurons associated with locomotion in the earthworm through synapse imaging

We used FM imaging to identify neurons that receive sensory feedback from the body wall in a circuit for octopamine (OA)-evoked rhythmic locomotion in the earthworm, Eisenia fetida. We visualized synapses in which postsynaptic neurons receive the sensory feedback, by using FM1-43 dye to label the synapses of both motor and sensory pathways that are associated with locomotion, then clearing the motor pathway synapse labeling, and finally identifying the target synapses by distinguishing physiologically functional synapses through destaining using a high-K(+) solution. A pair of synaptic regions associated with the sensory feedback was found to be located two or three cell body-widths away from the midline, between the anterior parts of the roots of the second lateral nerves (LNs) at the segmental ganglia (SGs). Using conventional intracellular recording and dye loading of the cell bodies surrounding these synaptic regions, we identified a pair of bilateral neurons with cell bodies larger than those of other cells in these regions, and named them "Oscillatory firing neurons Projecting to Peripheral nerves" (OPPs). These had a bipolar shape and projected neurites to the ipsilateral first and third LNs, fired rhythmically, and had a burst timing synchronized with the motor pattern bursts from the ipsilateral first LNs. Current injection into an OPP caused firing in the ipsilateral first LNs, supporting the hypothesis that OPPs functionally project to the peripheral nerves. OPPs also sent neurites to the adjacent anterior and posterior SGs, suggesting connections with the adjacent segments. We conclude that FM imaging can be used to identify neurons involved in specific functions, and that OPPs are the first neurons to be associated with OA-induced locomotion in the earthworm.

Arthroscopic debridement in the treatment of patients with osteoarthritis of the elbow, based on computer simulation

We retrospectively assessed the value of identifying impinging osteophytes using dynamic computer simulation of CT scans of the elbow in assisting their arthroscopic removal in patients with osteoarthritis of the elbow. A total of 20 patients were treated (19 men and one woman, mean age 38 years (19 to 55)) and followed for a mean of 25 months (24 to 29). We located the impinging osteophytes dynamically using computerised three-dimensional models of the elbow based on CT data in three positions of flexion of the elbow. These were then removed arthroscopically and a capsular release was performed.

The mean loss of extension improved from 23° (10° to 45°) pre-operatively to 9° (0° to 25°) post-operatively, and the mean flexion improved from 121° (80° to 140°) pre-operatively to 130° (110° to 145°) post-operatively. The mean Mayo Elbow Performance Score improved from 62 (30 to 85) to 95 (70 to 100) post-operatively. All patients had pain in the elbow pre-operatively which disappeared or decreased post-operatively. According to their Mayo scores, 14 patients had an excellent clinical outcome and six a good outcome; 15 were very satisfied and five were satisfied with their post-operative outcome.

We recommend this technique in the surgical management of patients with osteoarthritis of the elbow.

Cite this article: Bone Joint J 2014;96-B:237–41.

Intramural bronchogenic cyst of the oesophagus

Bronchogenic cysts are relatively common mediastinal cysts. Here, we report removal of a rare paraoesophageal-type bronchogenic cyst by video-assisted thoracoscopic surgery in a 52-year-old male patient. The defect of the oesophageal wall was successfully reinforced with an intercostal muscle flap.

Ca(2)Y(2)Cu(5)O(10): the first frustrated quasi-1D ferromagnet close to criticality

Ca(2)Y(2)Cu(5)O(10) is built up from edge-shared CuO(4) plaquettes forming spin chains. From inelastic neutron scattering data we extract an in-chain nearest-neighbor exchange J(1)≈-170  K and the frustrating next-neighbor J(2)≈32  K interactions, both significantly larger than previous estimates. The ratio α=|J(2)/J(1)|=0.19±0.01 places the system close to the critical point α(c)=0.25 of the J(1)-J(2) chain but in the 1D ferromagnetic regime. We establish that the vicinity to criticality only marginally affects the dispersion and coherence of the spin-wave-like magnetic excitations but instead results in a dramatic T dependence of high-energy Zhang-Rice singlet excitation intensities.

Carbohydrate response element-binding protein (ChREBP) plays a pivotal role in beta cell glucotoxicity

AIMS/HYPOTHESIS

This study was aimed at the elucidation of the pathogenesis of glucotoxicity, i.e. the mechanism whereby hyperglycaemia damages pancreatic beta cells. The identification of pathways in the process may help identify targets for beta cell-protective therapy. Carbohydrate response element-binding protein (ChREBP), a transcription factor that regulates the expression of multiple hyperglycaemia-induced genes, is produced in abundance in pancreatic beta cells. We hypothesise that ChREBP plays a pivotal role in mediating beta cell glucotoxicity.

METHODS

We assessed the role of ChREBP in glucotoxicity in 832/13 beta cells, isolated mouse islets and human pancreas tissue sections using multiple complementary approaches under control and high-glucose-challenge conditions as well as in adeno-associated virus-induced beta cell-specific overexpression of Chrebp (also known as Mlxipl) in mice.

RESULTS

Under both in vitro and in vivo conditions, ChREBP activates downstream target genes, including fatty acid synthase and thioredoxin-interacting protein, leading to lipid accumulation, increased oxidative stress, reduced insulin gene transcription/secretion and enhanced caspase activity and apoptosis, processes that collectively define glucotoxicity. Immunoreactive ChREBP is enriched in the nucleuses of beta cells in pancreatic tissue sections from diabetic individuals compared with non-diabetic individuals. Finally, we demonstrate that induced beta cell-specific Chrebp overexpression is sufficient to phenocopy the glucotoxicity manifestations of hyperglycaemia in mice in vivo.

CONCLUSIONS/INTERPRETATION

These data indicate that ChREBP is a key transcription factor that mediates many of the hyperglycaemia-induced activations in a gene expression programme that underlies beta cell glucotoxicity at the molecular, cellular and whole animal levels.