The potential use of bacterial community succession in forensics as described by high throughput metagenomic sequencing

Decomposition studies of vertebrate remains primarily focus on data that can be seen with the naked eye, such as arthropod or vertebrate scavenger activity, with little regard for what might be occurring with the microorganism community. Here, we discuss the necrobiome, or community of organisms associated with the decomposition of remains, specifically, the “epinecrotic” bacterial community succession throughout decomposition of vertebrate carrion. Pyrosequencing was used to (1) detect and identify bacterial community abundance patterns that described discrete time points of the decomposition process and (2) identify bacterial taxa important for estimating physiological time, a time–temperature metric that is often commensurate with minimum post-mortem interval estimates, via thermal summation models. There were significant bacterial community structure differences in taxon richness and relative abundance patterns through the decomposition process at both phylum and family taxonomic classification levels. We found a significant negative linear relationship for overall phylum and family taxon richness as decomposition progressed. Additionally, we developed a statistical model using high throughput sequencing data of epinecrotic bacterial communities on vertebrate remains that explained 94.4 % of the time since placement of remains in the field, which was within 2–3 h of death. These bacteria taxa are potentially useful for estimating the minimum post-mortem interval. Lastly, we provide a new framework and standard operating procedure of how this novel approach of using high throughput metagenomic sequencing has remarkable potential as a new forensic tool. Documenting and identifying differences in bacterial communities is key to advancing knowledge of the carrion necrobiome and its applicability in forensic science.     

Promoter hyper-methylation of calcium binding proteins S100A6 and S100A2 in human prostate cancer

BACKGROUND: S100A6 and S100A2 are members of the S100 family of calcium binding proteins, which are down regulated in prostate cancer, however the molecular mechanism(s) underlying their loss of expression is unknown. METHODS: The promoter and exon 1 region of the S100A6 and S100A2 genes was sequenced in bisulfite modified DNA from non-malignant, benign prostatic hyperplasia (BPH), malignant and metastatic prostate tissues and in cell lines. Immunohistochemistry was performed to correlate S100A2 expression with methylation status. RESULTS: S100A6 methylation was absent or occurred at isolated sites in 14/14 cases of non-malignant epithelium and 5/5 cases of BPH tissues, whereas methylation was seen in 14/27 (52%) cases of prostatic cancer (P<0.0001), 2/2 cases of metastatic cancer and in the CWR22 prostatic cancer xenograft. Critical CpG sites within the S100A2 promoter were methylated in LNCaP, LNCaP-LN3, and CWR22 cells but not in Du145, PC3 or BPH45 cells. In tissues, S100A2 methylation was seen in 32/34 (94%) cases of adenocarcinoma and 5/5 cases of metastatic cancer. However, S100A2 methylation was also seen in 9/12 (75%) cases of non-malignant tissues and in 5/5 cases of BPH. Immunostaining, showed absent S100A2 expression all 41 cases of prostatic cancer, whereas staining was seen in the basal cells of non-malignant epithelium. CONCLUSIONS: Loss of S100A6 and S100A2 proteins is frequent in human prostatic cancer. A major mechanism underlying the loss of S100A6 expression appears to involve promoter hyper-methylation. However, mechanisms other than methylation of the known promoter are involved in silencing S100A2 in the prostate.     

Tumor diameter accurately predicts perioperative outcomes in T1 renal cancer treated with robot-assisted partial nephrectomy

Purpose

To compare diameter as a continuous variable with categorical R.E.N.A.L. nephrometry score (RNS) in predicting surgical outcomes of robotic partial nephrectomy (RPN).

Methods

We retrospectively reviewed consecutive patients receiving RPN at our institution between July 2007 and June 2014 (n = 286). Three separate multivariate analyses were performed to assess the relationship between RNS components (R = radius, E = endophyticity, N = nearness to collecting system, L = location relative to polar lines), total RNS, and diameter as a continuous variable with operating time, warm ischemia time (WIT), and estimated blood loss (EBL). Each linear regression model’s quality of fit to the data was assessed with coefficients of determination (R ²).

Results

Continuous tumor diameter and total RNS were each significantly correlated to operative time, EBL, and WIT (p < 0.001). Categorical R related to operative time (R = 2 vs. R = 1, p = 0.001; R = 3 vs. R = 1, p = 0.001) and WIT (R = 2 vs. R = 1, p = 0.003; R = 3 vs. R = 1, p = 0.016), but not to EBL. For each of these outcomes, diameter outperformed both R and total RNS, as assessed by R ². Age, body mass index, Charlson Comorbidity Index, and anterior versus posterior location did not correlate with surgical outcomes.

Conclusions

In this series of RPN from a high-volume center, surgical outcomes more closely related to tumor diameter than RNS. While RNS provides surgeons a standardized tool for preoperative planning of renal masses, tumor size may be employed as a more familiar measurement when counseling patients on potential outcomes.

     

Structured Approach Therapy for Combat‐Related PTSD in Returning U.S. Veterans: Complementary Mediation by Changes in Emotion Functioning

To address the impact of combat‐related posttraumatic stress disorder (PTSD) on U.S. Operation Enduring Freedom (OEF) and Operation Iraqi Freedom (OIF) veterans, the investigators developed a 12‐session manualized PTSD treatment for couples called structured approach therapy (SAT). A randomized controlled trial had shown that 29 OEF/OIF veterans with combat‐related PTSD who had participated in SAT showed significantly greater reductions in PTSD compared to 28 veterans receiving a 12‐session PTSD family education intervention (Sautter, Glynn, Cretu, Senturk, & Vaught, 2015). We conducted supplemental follow‐up and mediation analyses, which tested the hypothesis that changes in emotion functioning play a significant role in the decreases in PTSD symptoms primarily observed in veterans who had received SAT. Veterans assigned to the SAT condition showed significantly greater decreases than those assigned to PTSD family education in emotion regulation problems (p < .001, Cohen's f² = .18) and fear of intense emotions (p < .001, Cohen's f² = .152). Decreases in both emotion regulation problems (mediated effect:= .36), and fear of intense emotions (mediated effect: = .24) were found to be complementary mediators of reductions in PTSD symptoms greater with SAT. These findings suggest that SAT may aid veterans in improving their ability to regulate trauma‐related emotions.     

Anatomic Bladder Neck Preservation During Robotic-Assisted Laparoscopic Radical Prostatectomy: Description of Technique and Outcomes

Background

Robotic-assisted laparoscopic radical prostatectomy (RALP) has been rapidly adopted despite a daunting learning curve with bladder neck dissection as a challenging step for newcomers.

Objective

To describe an anatomic, reproducible technique of bladder neck preservation (BNP) and associated perioperative and long-term outcomes.

Design, settings, and participants

From September 2005 to May 2009, data from 619 consecutive RALP were prospectively collected and compared on the basis of bladder neck dissection technique with 348 BNP and 271 standard technique (ST).

Surgical procedure

RALP with BNP.

Measurements

Tumor characteristics, perioperative complications, and post-operative urinary control were evaluated at 4, 12 and 24 months using (1) the Expanded Prostate Cancer Index (EPIC) urinary function scale scored from 0–100; and (2) continence defined as zero pads per day.

Results and limitations

Mean age for BNP versus ST was 57.1 ± 6.6 yr versus 58.9 ± 6.7 yr (p = 0.033), while complication rates did not vary significantly by technique. Estimated blood loss was 183.7 ± 95.8 ml versus 224.6 ± 108 ml (p = 0.938) in men who underwent BNP versus ST. The overall positive margin rate was 12.8%, which did not differ at the prostate base for BNP versus ST (1.4% vs. 2.2%, p = 0.547). Mean urinary function scores for BNP versus ST at 4, 12, and 24 mo were 64.6 versus 57.2 (p = 0.037), 80.6 versus 79.0 (p = 0.495), and 94.1 versus 86.8 (p < 0.001). Similarly, BNP versus ST continence rates at 4, 12, and 24 mo were 65.6% versus 26.5% (p < 0.001), 86.4% versus 81.4% (p = 0.303), and 100% versus 96.1% (p = 0.308).

Conclusions

BNP versus ST is associated with quicker recovery of urinary function and similar cancer control.     

Expanding surgical clerkships to remote community sites: the success of the Washington, Wyoming, Alaska, Montana, and Idaho experience

Background

The purpose of this analysis was to determine if the surgical clerkship model and site affect educational outcomes and student postclerkship perceptions.

Methods

Data from University of Washington students participating in surgical clerkships at traditional/academic or community/apprentice sites across Washington, Wyoming, Alaska, Montana, and Idaho (WWAMI) between 2005 and 2007 were gathered retrospectively. Comparisons of final examination scores as well as postclerkship student evaluations of the educational experience were made between traditional and community training sites.

Results

The mean final examination scores at WWAMI sites were significantly higher than those at traditional academic sites. Furthermore, WWAMI sites were rated higher with respect to time spent by faculty in direct observation, quality of the clerkship as a whole, and overall contribution to medical education.

Conclusions

Community surgical clerkship sites remote from an academic institution can provide an excellent learning experience for students.     

Evidence-based practice in laparoscopic surgery: perioperative care

Best practices for reducing risks of postoperative infection, venous thromboembolism, and nausea and vomiting in patients undergoing laparoscopic surgery are uncertain. As a result, perioperative care varies widely. We reviewed evidence from randomized clinical trials on the effectiveness of interventions for postoperative infection, venous thromboembolism, and nausea and vomiting Data sources were the Cochrane Central Register of Clinical Trials, reference lists of published trials, and randomized clinical trials published in English since 1990. Trials were also limited to those focused on patients undergoing laparoscopic surgery. Data from 98 randomized clinical trials were included in the final analysis. Routine antibiotic use in laparoscopic cholecystectomy, and possibly other clean procedures not involving placement of prostheses, is likely unnecessary. Similarly, venous thromboembolism prophylaxis is probably unnecessary for low-risk patients undergoing brief procedures. Of a wide variety of methods for reducing postoperative nausea and vomiting, serotonin receptor antagonists appear the most effective and should be considered for routine prophylaxis.