Conversion to open surgery in obese patients undergoing minimally invasive distal pancreatectomy: results from a multicenter analysis.

BACKGROUND: Although minimally invasive distal pancreatectomy (MIDP) is considered a standard approach it still presents a non-negligible rate of conversion to open that is mainly related to some difficulty factors, as obesity. The aim of this study is to analyze the preoperative factors associated with conversion in obese patients with MIDP. METHODS: In this multicenter study, all obese patients who underwent MIDP at 18 international expert centers were included. The preoperative factors associated with conversion to open surgery were analyzed. RESULTS: Out of 436 patients, 91 (20.9%) underwent conversion to open, presenting higher blood loss, longer operative time and similar rate of major complications. Twenty (22%) patients received emergent conversion. At univariate analysis, the type of approach, radiological invasion of adjacent organs, preoperative enlarged lymphnodes and ASA ≥ III were significantly associated with conversion to open. At multivariate analysis, robotic approach showed a significantly lower conversion rate (14.6 % vs 27.3%, OR = 2.380, p = 0.001). ASA ≥ III (OR = 2.391, p = 0.002) and preoperative enlarged lymphnodes (OR = 3.836, p = 0.003) were also independently associated with conversion. CONCLUSION: Conversion rate is significantly lower in patients undergoing robotic approach. Radiological enlarged lymphnodes and ASA ≥ III are also associated with conversion to open. Conversion is associated with poorer perioperative outcomes, especially in case of intraoperative hemorrhage.

Comparing brute force to transition path sampling for gas hydrate nucleation with a flat interface: comments on time reversal symmetry.

Fluid to solid nucleation is often investigated with the rare event method transition path sampling (TPS). I claim that the inherent irreversibility of solid nucleation, even at stationary conditions, calls into question TPS's applicability for determining solid nucleation mechanisms, especially for pre-critical behavior. Even when applied to a phenomenon which displays time reversal asymmetry like solid nucleation, TPS is a good means of exploring phase space and giving trends in post-critical structure, and its ability to facilitate nucleation rate and free energy calculations remains outstanding. Forward-only splitting and ratcheting methods such as forward flux sampling are more attractive for understanding nucleation mechanisms as they do not require time reversal symmetry, but at low driving forces may suffer from the same limitations as brute force: they may never make it to the first ratchet. Here I briefly summarize the TPS method and gas hydrate nucleation simulation literature, focusing on topics within both to facilitate a comparison of brute force hydrate nucleation to transition path sampling of hydrate nucleation. Perhaps anecdotally, the brute force technique results in more crystalline trajectories despite having higher driving forces than TPS. I maintain this difference is because of the inherent irreversibility of hydrate nucleation, meaning its pre-critical behavior cannot accurately be determined by the melting trajectories that comprise approximately half of the configurations in TPS's path ensemble.

Robotic versus laparoscopic distal pancreatectomy for pancreatic adenocarcinoma in obese patients.

BACKGROUND: Robotic distal pancreatectomy (RDP) is associated with a lower conversion rate and less blood loss than laparoscopic distal pancreatectomy (LDP). LDP has similar oncological outcomes as open surgery in PDAC. The aim of this study was to compare perioperative and oncological outcomes in obese patients with RDP versus LDP for PDAC. MATERIALS AND METHODS: Retrospectively, all obese patients who underwent RDP or LDP for PDAC between 2012 and 2022 at 12 international expert centres were included. RESULTS: out of 372, 81 patients were included. All baseline features were comparable between the two groups. RDP was associated with decreased blood loss (495mlLDP vs. 188mlRDP; p = 0.003), lower conversion rate (13.5%RDP vs. 36.4%LDP; p = 0.019) and lower rate of Clavien-Dindo ≥3 complications (13.5%RDP vs. 36.4%LDP; p = 0.019). Overall and disease-free survival were comparable. CONCLUSIONS: In obese patients with left-sided PDAC, the robotic approach was associated with improved intraoperative outcomes and fewer severe complications.

Incidence and risk factors for recurrence of ampullary adenomas after endoscopic papillectomy: Comparative analysis of familial adenomatous polyposis and sporadic ampullary adenomas in an international multicenter cohort.

OBJECTIVES: Endoscopic papillectomy (EP) is a minimally invasive therapy for the management of ampullary adenomas (AA). We conducted this multicenter study to assess the incidence of and factors related to the recurrence of AA after EP in patients with familial adenomatous polyposis (FAP) compared to sporadic AA. METHODS: We included patients who underwent EP for AA at 10 tertiary hospitals. Adenomatous tissue at the resection site at the time of surveillance endoscopies was considered recurrent disease. RESULTS: In all, 257 patients, 100 (38.9%) with FAP and 157 (61%) patients with sporadic AA, were included. Over a median of 31 (range, 11-61) months, recurrence occurred in 48/100 (48%) of patients with FAP and 58/157 (36.9%) with sporadic AA (P = 0.07). Two (2%) FAP patients and 10 (6.3%) patients with sporadic AA underwent surgery for recurrence. On multivariable regression analysis, the recurrence in FAP was higher than in sporadic patients after the first year of follow-up. AA size (hazard ratio [HR] 1.03, 95% confidence interval [CI] 1.001, 1.056), periampullary extension (HR 2.5, 95% CI 1.5, 4.01), and biliary duct dilation (HR 2.04, 95% CI 1.2, 3.4) increased the risk, while en bloc resection (HR 0.6, 95% CI 0.41, 0.9) decreased the risk of recurrence. CONCLUSION: Recurrence rates are high after EP. Most recurrences in sporadic patients occur within the first year of follow-up, but after the first year of follow-up in patients with FAP. Recurrences are higher with larger adenomas, biliary duct dilation, and periampullary extensions, and may be mitigated by en bloc resection. These factors should be considered in decision-making with the patients.

Robotic versus laparoscopic distal pancreatectomy in obese patients.

BACKGROUND: Although robotic distal pancreatectomy (RDP) has a lower conversion rate to open surgery and causes less blood loss than laparoscopic distal pancreatectomy (LDP), clear evidence on the impact of the surgical approach on morbidity is lacking. Prior studies have shown a higher rate of complications among obese patients undergoing pancreatectomy. The primary aim of this study is to compare short-term outcomes of RDP vs. LDP in patients with a BMI ≥ 30. METHODS: In this multicenter study, all obese patients who underwent RDP or LDP for any indication between 2012 and 2022 at 18 international expert centers were included. The baseline characteristics underwent inverse probability treatment weighting to minimize allocation bias. RESULTS: Of 446 patients, 219 (50.2%) patients underwent RDP. The median age was 60 years, the median BMI was 33 (31-36), and the preoperative diagnosis was ductal adenocarcinoma in 21% of cases. The conversion rate was 19.9%, the overall complication rate was 57.8%, and the 90-day mortality rate was 0.7% (3 patients). RDP was associated with a lower complication rate (OR 0.68, 95% CI 0.52-0.89; p = 0.005), less blood loss (150 vs. 200 ml; p < 0.001), fewer blood transfusion requirements (OR 0.28, 95% CI 0.15-0.50; p < 0.001) and a lower Comprehensive Complications Index (8.7 vs. 8.9, p < 0.001) than LPD. RPD had a lower conversion rate (OR 0.27, 95% CI 0.19-0.39; p < 0.001) and achieved better spleen preservation rate (OR 1.96, 95% CI 1.13-3.39; p = 0.016) than LPD. CONCLUSIONS: In obese patients, RDP is associated with a lower conversion rate, fewer complications and better short-term outcomes than LPD.

Nutritional Risks in Patients Undergoing Total Pancreatectomy Islet AutoTransplantation in the POST Consortium.

BACKGROUND AND AIMS: Total pancreatectomy with islet autotransplantation (TPIAT) can relieve pain for individuals with acute recurrent or chronic pancreatitis. However, TPIAT may increase the risk of poor nutritional status with complete exocrine pancreatic insufficiency, partial duodenectomy, and intestinal reconstruction. Our study's objective was to evaluate nutritional status, anthropometrics, and vitamin levels before and after TPIAT. METHODS: The multicenter Prospective Observational Study of TPIAT (POST) collects measures including vitamins A, D, and E levels, pancreatic enzyme dose, and multivitamin (MVI) administration before and 1-year after TPIAT. Using these data, we studied nutritional and vitamin status before and after TPIAT. RESULTS: 348 TPIAT recipients were included (68% adult, 37% male, 93% Caucasian). In paired analyses at 1-year follow-up, vitamin A was low in 23% (vs 9% pre-TPIAT, p < 0.001); vitamin E was low in 11% (vs 5% pre-TPIAT, p = 0.066), and 19% had vitamin D deficiency (vs 12% pre-TPIAT, p = 0.035). Taking a fat-soluble multivitamin (pancreatic MVI) was associated with lower risk for vitamin D deficiency (p = 0.002). Adults were less likely to be on a pancreatic MVI at follow-up (34% vs 66% respectively, p < 0.001). Enzyme dosing was adequate. More adults versus children were overweight or underweight pre- and post-TPIAT. Underweight status was associated with vitamin A (p = 0.014) and E (p = 0.02) deficiency at follow-up. CONCLUSIONS: Prevalence of fat-soluble vitamin deficiencies increased after TPIAT, especially if underweight. We strongly advocate that all TPIAT recipients have close post-operative nutritional monitoring, including vitamin levels. Pancreatic MVIs should be given to minimize risk of developing deficiencies.

Self-reported hearing loss is associated with poorer perceived health care access, timeliness, satisfaction, and quality: Findings from the Survey of the Health of Wisconsin.

BACKGROUND: Hearing loss is a highly prevalent chronic condition impacting communication and may negatively influence patients' health care experiences. OBJECTIVE: Determine associations of hearing loss with perceived health care access, timeliness, satisfaction, and quality in a representative sample of the general population. METHODS: The Survey of the Health of Wisconsin (SHOW) is a household-based examination survey that collects data from a representative sample of Wisconsin residents. SHOW participants from years 2008-2013 with data on self-reported hearing loss and health care access, timeliness, satisfaction, and quality were included in this study. Age- and sex- and multivariable-adjusted (additionally adjusted for race/ethnicity, education, marital status, public health region, smoking, chronic disease, self-reported health, and insurance coverage) logistic regression models were used to evaluate associations of hearing loss with participants' health care experiences. Results are presented as odds ratios (OR) with corresponding 95% confidence intervals. RESULTS: There were 2438 individuals (42.1% men) included in this study with an average age of 48.3 (range 21-74; standard deviation [SD] 14.4) years. The number of participants who self-reported hearing loss was 642 (26.3%). After multivariable adjustment, hearing loss was associated with increased odds of perceived difficulties with health care access (OR 1.47 [1.05, 2.05]), timeliness (OR 1.69 [1.23, 2.32]), quality (OR 2.54 [1.50, 4.32]), and satisfaction (OR 2.50 [1.51, 4.13]). CONCLUSIONS: Given the high prevalence of hearing loss and the growing aging population, there is an urgent need to prioritize interventions to improve health care provision for individuals with hearing loss.

Use of fluorescence imaging and indocyanine green during laparoscopic cholecystectomy: Results of an international Delphi survey.

BACKGROUND: Published empirical data have increasingly suggested that using near-infrared fluorescence cholangiography during laparoscopic cholecystectomy markedly increases biliary anatomy visualization. The technology is rapidly evolving, and different equipment and doses may be used. We aimed to identify areas of consensus and nonconsensus in the use of incisionless near-infrared fluorescent cholangiography during laparoscopic cholecystectomy. METHODS: A 2-round Delphi survey was conducted among 28 international experts in minimally invasive surgery and near-infrared fluorescent cholangiography in 2020, during which respondents voted on 62 statements on patient preparation and contraindications (n = 12); on indocyanine green administration (n = 14); on potential advantages and uses of near-infrared fluorescent cholangiography (n = 18); comparing near-infrared fluorescent cholangiography with intraoperative x-ray cholangiography (n = 7); and on potential disadvantages of and required training for near-infrared fluorescent cholangiography (n = 11). RESULTS: Expert consensus strongly supports near-infrared fluorescent cholangiography superiority over white light for the visualization of biliary structures and reduction of laparoscopic cholecystectomy risks. It also offers other advantages like enhancing anatomic visualization in obese patients and those with moderate to severe inflammation. Regarding indocyanine green administration, consensus was reached that dosing should be on a milligrams/kilogram basis, rather than as an absolute dose, and that doses >0.05 mg/kg are necessary. Although there is no consensus on the optimum preoperative timing of indocyanine green injections, the majority of participants consider it important to administer indocyanine green at least 45 minutes before the procedure to decrease the light intensity of the liver. CONCLUSION: Near-infrared fluorescent cholangiography experts strongly agree on its effectiveness and safety during laparoscopic cholecystectomy and that it should be used routinely, but further research is necessary to establish optimum timing and doses for indocyanine green.

Efficacy of endoscopic retrograde cholangiopancreatography in familial adenomatous polyposis patients after duodenectomy.

Objectives: Familial adenomatous polyposis (FAP) patients with Spigelman stage IV polyposis should be considered for prophylactic duodenectomy. Post-surgical pancreaticobiliary complications occur and may require management via endoscopic retrograde cholangiopancreatography (ERCP). We aimed to assess the success and adverse events of ERCP in FAP patients after pancreas-sparing duodenectomy (PSD) and pancreaticoduodenectomy (PD). Methods: A retrospective review of FAP patients who underwent ERCP after PSD or PD from 1992 to 2020 at a quaternary referral center was completed. The technical success of ERCP was defined as the ability to identify the anastomosis and cannulate the duct. Post-procedural adverse events were defined by bleeding, perforation, pancreatitis, or cholangitis. Clinical outcomes included the need for surgical intervention and recurrent pancreatitis after ERCP were assessed. Results: Of 84 FAP patients with duodenectomy, 12 patients with PSD and two patients with PD underwent 17 ERCPs for pancreatic indications and five for biliary indications. The technical success of ERCP in patients with PSD and a single neoampullary complex for pancreatic (n = 6) and biliary (n = 5) indications was 100% but for those with PD (n = 2) or PSD reconstruction with pancreatic divisum or separate anastomoses (n = 3), it was 0%. Surgical intervention was required in 50% of patients with technically failed ERCP after PSD (2/4) and PD (1/2). There were no adverse events. Conclusions: ERCP is expected to be therapeutically successful for biliary complications following PSD. Assessment and potential therapy for pancreatitis post-PSD are best in the setting of a single neo-ampullary complex rather than in PD or PSD with pancreatic divisum.

Surgical approach and short-term outcomes in adults and children undergoing total pancreatectomy with islet autotransplantation: A report from the Prospective Observational Study of TPIAT.

BACKGROUND: Total pancreatectomy with islet autotransplantation (TPIAT) is a viable option for treating debilitating recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP) in adults and children. No data is currently available regarding variation in approach to operation. METHODS: We evaluated surgical techniques, islet isolation and infusion approaches, and outcomes and complications, comparing children (n = 84) with adults (n = 195) enrolled between January 2017 and April 2020 by 11 centers in the United States in the Prospective Observational Study of TPIAT (POST), which was launched in 2017 to collect standard history and outcomes data from patients undergoing TPIAT for RAP or CP. RESULTS: Children more commonly underwent splenectomy (100% versus 91%, p = 0.002), pylorus preservation (93% versus 67%; p < 0.0001), Roux-en-Y duodenojejunostomy reconstruction (92% versus 35%; p < 0.0001), and enteral feeding tube placement (93% versus 63%; p < 0.0001). Median islet equivalents/kg transplanted was higher in children (4577; IQR 2816-6517) than adults (2909; IQR 1555-4479; p < 0.0001), with COBE purification less common in children (4% versus 15%; p = 0.0068). Median length of hospital stay was higher in children (15 days; IQR 14-22 versus 11 days; IQR 8-14; p < 0.0001), but 30-day readmissions were lower in children (13% versus 26%, p = 0.018). Rate of portal vein thrombosis was significantly lower in children than in adults (2% versus 10%, p = 0.028). There were no mortalities in the first 90 days post-TPIAT. CONCLUSIONS: Pancreatectomy techniques differ between children and adults, with islet yields higher in children. The rates of portal vein thrombosis and early readmission are lower in children.

Bioenergetics of Islet Preparations in a Pilot Clinical Trial of Peri-Transplant Hydroxychloroquine for Autologous Islet Transplantation.

The inflammatory response is an obstacle to success in both allogeneic and autologous islet transplantation. In autologous islet transplantation (AIT), however, the recipient is also the donor, permitting pretreatment of donor/recipient for a controlled duration prior to transplantation. We sought to exploit this feature of (AIT) by pretreating donor/recipients with chronic pancreatitis undergoing total pancreatectomy and autologous islet transplantation (TPAIT) to test the hypothesis that peri-transplant treatment with the FDA-approved anti-inflammatory hydroxychloroquine (HCQ) improves graft function. In this randomized placebo-controlled pilot clinical study, patients (n = 6) were treated with oral HCQ for 30 days prior to and 90 days after TPAIT. In vivo islet function was assessed via Mixed Meal Tolerance Testing before HCQ treatment, 6- and 12-months after surgery. In vitro islet bioenergetics were assessed at the time of transplantation via extracellular flux analysis of islet preparation samples from the clinical trial cohort and six additional patients (n = 12). Our study shows that HCQ did not alter clinical endpoints, but HCQ-treated patients showed greater spare respiratory capacity (SRC) compared to samples from control patients (P=0.028). Glycolytic metabolism of islet preparations directly correlated with stimulated C-peptide secretion both before and after TPAIT (P=0.01, R2=0.489 and P=0.03, R2=0.674, respectively), and predicted in vivo islet function better than mitochondrial metabolism of islet preps or islet equivalents infused. Overnight culture of islet preparations altered bioenergetic function, significantly decreasing SRC and maximal respiration (P<0.001). In conclusion, while HCQ did not alter clinical outcomes, it was associated with significantly increased SRC in islet preparations. Bioenergetic analyses of islet preparations suggests that culture should be avoided and that glycolysis may be a more sensitive indicator of in vivo islet function than current metrics, including islet oxygen consumption and islet equivalents infused.

Spontaneous Internal Pancreatic Fistulae Complicating Acute Pancreatitis.

Spontaneous pancreatic fistula (PF) is a rare but challenging complication of acute pancreatitis (AP). The fistulae could be internal (draining into another viscera or cavity, e.g., pancreaticocolonic, gastric, duodenal, jejunal, ileal, pleural, or bronchial) or external (draining to skin, i.e., pancreaticocutaneous). Internal fistulae constitute the majority of PF and will be discussed in this review. Male sex, alcohol abuse, severe AP, and infected necrosis are the major risk factors for development of internal PF. A high index of suspicion is required to diagnose PF. Broad availability of computed tomography makes it the initial test of choice. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography have higher sensitivity compared with computed tomography scan and also allow for assessment of pancreatic duct for leak or disconnection, which affects treatment approaches. Certain complications of PF including hemorrhage and sepsis could be life-threatening and require urgent intervention. In nonurgent/chronic cases, management of internal PF involves control of sepsis, which requires effective drainage of any residual pancreatic collection/necrosis, sometimes by enlarging the fistula. Decreasing fistula output with somatostatin analogs (in pancreaticopleural fistula) and decreasing intraductal pressure with endoscopic retrograde cholangiopancreatography or endoscopic ultrasound/interventional radiology-guided interventions or surgery are commonly used strategies for management of PF. More than 60% of the internal PF close with medical and nonsurgical interventions. Colonic fistula, medical refractory-PF, or PF associated with disconnected pancreatic duct can require surgical intervention including bowel resection or distal pancreatectomy. In conclusion, AP-induced spontaneous internal PF is a complex complication requiring multidisciplinary care for successful management.

Cell Block Optimization: A Comparative Study of Quality Variables in 4 Different Cell Block Methods.

OBJECTIVE: The cell block (CB) is an important adjunct to cytological preparations in diagnostic cytopathology. Optimizing cellular material in the CB is essential to the success of ancillary studies such as immunohistochemistry (IHC) and molecular studies (MS). Our aim was to identify which CB method was most suitable in a variety of specimen types and levels of cellularity. STUDY DESIGN: We assessed 4 different CB methods, thrombin clot method (TCM), MD Anderson method (MDAM), gelatin foam method (GFM), and agar method (AM), with descriptive observations and ranking of the methods based on quantity of cells and morphological features. RESULTS: TCM performed best in ranking for both quantity of cells and morphological features, followed by MDAM, GFM, and AM. Lack of adjuvant in the MDAM resulted in some unique morphological advantages which, however, also resulted in inconsistent performance. In low cellularity cases insufficient cells were frequently identified on slides from MDAM and AM CBs. Technique touch time was similar for all methods, with total processing time being shortest for TCM followed by MDAM, GFM, and AM. CONCLUSIONS: TCM was the most robust CB technique, retaining high scores for ranking of quantity and morphology in a variety of specimen cellularities and specimen types.

Regulation of T cell-associated tissues and T cell activation by RANKL-RANK-OPG.

The receptor activator of nuclear factor kappa-B ligand (RANKL)-RANK-osteoprotegerin (OPG) system is critical to bone homeostasis, but genetically deficient mouse models have revealed important roles in the immune system as well. RANKL-RANK-OPG is particularly important to T cell biology because of its organogenic control of thymic development and secondary lymphoid tissues influence central T cell tolerance and peripheral T cell function. RANKL-RANK-OPG cytokine-receptor interactions are often controlled by regulation of expression of RANKL on developing T cells, which interacts with RANK expressed on some lymphoid tissue cells to stimulate key downstream signaling pathways that affect critical tuning functions of the T cell compartment, like cell survival and antigen presentation. Activation of peripheral T cells is regulated by RANKL-enhanced dendritic cell survival, and dysregulation of the RANKL-RANK-OPG system in this context is associated with loss of T cell tolerance and autoimmune disease. Given its broader implications for immune homeostasis and osteoimmunology, it is critical to further understand how the RANKL-RANK-OPG system operates in T cell biology.

Endoscopic Surveillance of Duodenal Polyposis After Total Gastrectomy in Familial Adenomatous Polyposis.

The lifetime incidence of duodenal polyposis in familial adenomatous polyposis (FAP) approaches 100%, and duodenal cancer is the most common malignancy once colectomy is performed. The incidence of gastric cancer is increasing in patients with FAP, and when gastric polyps with high-grade dysplasia or cancer are present, a total gastrectomy with Roux-en-Y esophagojejunostomy is indicated. The altered anatomy after surgery and presence of adhesions from a previous colectomy make endoscopic surveillance of the duodenum with standard equipment difficult. This case report highlights an approach to duodenal polyposis surveillance in FAP after total gastrectomy with Roux-en-Y esophagojejunostomy.

Protocadherin-7 contributes to maintenance of bone homeostasis through regulation of osteoclast multinucleation.

Osteoclasts are hematopoietic-derived cells that resorb bone. They are required to maintain proper bone homeostasis and skeletal strength. Although osteoclast differentiation depends on receptor activator of NF-κB ligand (RANKL) stimulation, additional molecules further contribute to osteoclast maturation. Here, we demonstrate that protocadherin-7 (Pcdh7) regulates formation of multinucleated osteoclasts and contributes to maintenance of bone homeostasis. We found that Pcdh7 expression is induced by RANKL stimulation, and that RNAi-mediated knockdown of Pcdh7 resulted in impaired formation of osteoclasts. We generated Pcdh7-deficient mice and found increased bone mass due to decreased bone resorption but without any defect in bone formation. Using an in vitro culture system, it was revealed that formation of multinucleated osteoclasts is impaired in Pcdh7-deficient cultures, while no apparent defects were observed in differentiation and function of Pcdh7-deficient osteoblasts. Taken together, these results reveal an osteoclast cell-intrinsic role for Pcdh7 in maintaining bone homeostasis. [BMB Reports 2020; 53(9): 472-477].

Mice Lacking the Purinergic Receptor P2X5 Exhibit Defective Inflammasome Activation and Early Susceptibility to Listeria monocytogenes.

P2X5 is a member of the P2X purinergic receptor family of ligand-gated cation channels and has recently been shown to regulate inflammatory bone loss. In this study, we report that P2X5 is a protective immune regulator during Listeria monocytogenes infection, as P2X5-deficient mice exhibit increased bacterial loads in the spleen and liver, increased tissue damage, and early (within 3-6 d) susceptibility to systemic L. monocytogenes infection. Whereas P2X5-deficient mice experience normal monocyte recruitment in response to L. monocytogenes, P2X5-deficient bone marrow-derived macrophages (BMMs) exhibit defective cytosolic killing of L. monocytogenes We further showed that P2X5 is required for L. monocytogenes-induced inflammasome activation and IL-1ß production and that defective L. monocytogenes killing in P2X5-deficient BMMs is substantially rescued by exogenous IL-1ß or IL-18. Finally, in vitro BMM killing and in vivo L. monocytogenes infection experiments employing either P2X7 deficiency or extracellular ATP depletion suggest that P2X5-dependent anti-L. monocytogenes immunity is independent of the ATP-P2X7 inflammasome activation pathway. Together, our findings elucidate a novel and specific role for P2X5 as a critical mediator of protective immunity.

Highly accurate classification of biological spores by culture medium for forensic attribution using multiple chemical signature types and machine learning.

Future proliferation of biological expertise and new technology may increasingly lower the difficulty to produce biological organisms for misuse. Rapid attribution of a biological attack is needed to quickly identify the person or lab responsible and prevent additional attacks by enabling the apprehension of suspects. Here, triplicate batches of Bacillus anthracis Sterne strain (BaSt) spores were grown in a total of seven amateur and professional media. Multiple orthogonal analytical signatures (peptides, metabolites, lipids by fatty acid methyl ester (FAME) analysis, bulk organic profile, and trace elements) were collected from the BaSt spores. The proteomics and metabolomics analyses identified promising attribution signature compounds that are unique to each of the seven production methods. In addition, while each of the signature types showed varying degrees of value individually for attributing BaSt spores to the culture medium used to prepare them, fusing results from all five signatures types to increase sourcing robustness and using a random forest sourcing algorithm yielded 100% hold-one-batch-out cross-validation classification accuracy and an average relative source probability for the correct source 5.5× higher than the most probable incorrect source. These preliminary results provide a proof-of-concept for the development of forensic examinations that can attribute biological agents to production methods for use in future investigations.

Incisionless fluorescent cholangiography (IFC): a pilot survey of surgeons on procedural familiarity, practices, and perceptions.

BACKGROUND: Incisionless fluorescent cholangiography (IFC) has recently been proven feasible, safe, and efficacious as an intraoperative procedure to help identify extrahepatic bile ducts during laparoscopic cholecystectomies (LC). We conducted a pilot survey of 51 surgeons attending an international conference who perform endoscopic cholecystectomies to identify their typical LC practices, and perceptions of IFC. METHODS: An international panel of ten IFC experts, all with > 500 prior IFC procedures and related research publications, convened during the 4th International Congress of Fluorescence-Guided Surgery in Boca Raton, Florida in February 2017. The panel was charged with developing questions about LC practices and experience with IFC, and perceptions regarding its advantages, barriers to use, and indications. These questions then were asked to other congress attendees during one of the didactic sessions using an online polling application. Attendees, who ranged from zero to considerable experience performing IFC, accessed the survey via their portable devices. RESULTS: Of the 51 survey participants, 51% were from North America; 77% identified themselves as general/minimally invasive surgeons, and roughly 60% performed under 50 cholecystectomies/year. Only 12% performed routine intraoperative cholangiography (IOC), while 72.3% routinely performed critical safety reviews. Thirty-five percent estimated that their institution's laparoscopic-to-open surgery conversion rate was > 1% during LC. Roughly 95% of respondents felt that surgeons should have access to a noninvasive method for evaluating extrahepatic biliary structures; 84% felt that the most advantageous characteristic of IFC is the lack of any biliary-tree incision; and 93.3% felt that IFC would have considerable educational value in surgical training programs; and 78% felt that any surgeon who performs LC could benefit. CONCLUSIONS: Surgeons who participated in our survey overwhelmingly recommended the routine use of IFC during laparoscopic cholecystectomy as a complimentary imaging technique. Prospective randomized clinical trials remain necessary to determine whether IFC reduces the incidence of bile duct injuries and other LC complications.