Operative Management of Acute Appendicitis Was Safe During the COVID-19 Pandemic Shutdown.

INTRODUCTION: In the spring of 2020, New York City was one of the first epicenters of the COVID outbreak. In this study, we evaluate the incidence and treatment of appendicitis in two New York City community hospitals during the COVID pandemic. METHODS: This retrospective study focused on the incidence and outcome of acute appendicitis in the adult population (>18 y old) during peak-COVID periods (March 16, 2020,-June 15, 2020) compared to pre-COVID and post-COVID periods. We compared the number of patients who underwent operative versus nonoperative management, patient demographics, length of stay (LOS), complications, and readmission rates within these time periods. Data are presented as mean ± standard deviation (analysis of variance). RESULTS: From January 1, 2020 to December 31, 2020, 393 patients presented with acute appendicitis and 321 (81.7%) were treated operatively, compared to 441 total and 366 treated operatively (83%) in 2019 (P = 0.88). During the COVID outbreak, fewer patients presented with appendicitis (mean 6.9 ± 1 pre-COVID case/week, 4.4 ± 2.4 peak-COVID cases/week and 7.6 ± 0.65 post-COVID cases/week, P = 0.018) with no significant difference in the pre-COVID and post-COVID period. There was no difference in LOS between the pre-, peak-, and post-COVID periods with a median of 1 for all the three, (interquartile range (IQR): 0.8-2, 0.6-2, 0.6-2, respectively, P = 0.43). Additionally, there was no difference in 30-day readmission rates (4.2%, 0%, 3.9%, P = 0.99) and postoperative complications (4.2%, 0%, 2.9%, P = 0.98). CONCLUSIONS: During peak-COVID, there was a significant reduction in the number of patients who presented with acute appendicitis without a post rebound increase in presentation. Those who presented during peak-COVID were able to undergo operative management safely, without affecting LOS or postoperative complications.

Long-term outcomes following laparoscopic Roux-en-Y gastric bypass: weight loss and resolution of comorbidities at 15 years and beyond.

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the gold-standard bariatric procedure with proven efficacy in morbidly obese populations. While the short-term benefits of LRYGB have been well-documented, durable weight loss and long-term resolution of obesity-related comorbidities have been less clearly described. METHODS: This single-center study prospectively reports weight loss and comorbidity resolution in patients undergoing LRYGB between August 2001 and September 2007 with at least 15-year follow-up. Data were collected at the time of surgery; 1, 3, 6, and 12 months postoperatively; and then annually thereafter. RESULTS: A total of 486 patients were included in this analysis. Patients were predominantly female (88.7%), and the median age was 36.0 [IQR 29.0-45.0] years. Patients were ethnically diverse, including Black/African American (43.6%), White/Caucasian (35.0%), Hispanic (18.3%), and other backgrounds (3.1%). Mean preoperative weight and body mass index were 133.0 ± 21.9 kg and 48.4 ± 6.5 kg/m2, and the median number of comorbidities was 6.0 [IQR 4.0-7.0]. Follow-up rates at 1, 5, 10, and 15 years were 75.3%, 37.2%, 35.2%, and 18.9%, respectively. On average, maximum percentage total weight loss (%TWL) occurred 2 years postoperatively (- 36.2 ± 9.5%), and ≥ 25% TWL was consistently achieved at 1, 5, 10, and 15-year time intervals (- 28.0 ± 13.0% at 15 years). Patients with comorbidities experienced improvement or resolution of their conditions within 1 year, including type 2 diabetes mellitus (83/84, 98.8%), obstructive sleep apnea (112/116, 96.6%), hypertension (142/150, 94.7%), and gastroesophageal reflux disease (217/223, 97.3%). Rates of improved/resolved comorbidities remained consistently high through at least 10 years after surgery. CONCLUSIONS: LRYGB provides durable weight loss for at least 15 years after surgery, with stable average relative weight loss of approximately 25% from baseline. This outcome corresponds with sustainable resolution of obesity-related comorbidities for at least 10 years after the initial operation.

Long-term weight loss after bariatric procedures for morbidly obese adolescents and youth: a single-institution analysis with up to 19-year follow-up.

BACKGROUND: Obesity is a public health concern among adolescents and young adults. Bariatric surgery is the most effective treatment for morbid obesity and has been increasingly utilized in young patients. Long-term outcomes data for bariatric surgery in this age group are limited. METHODS: This is a single-institution, prospective analysis of 167 patients aged 15-24 years who underwent one of three laparoscopic bariatric procedures between 2001 and 2019: Roux-en-Y gastric bypass (LRYGB, n = 71), adjustable gastric banding (LAGB, n = 22), and sleeve gastrectomy (LSG, n = 74). Longitudinal weight and body mass index (BMI) measurements were compared to evaluate patterns of weight loss. RESULTS: All operations were completed laparoscopically using the same clinical pathways. Patients were predominantly female (82.6%), had a median age of 22.0 [Q1-Q3 20.0-23.0] years, and had a mean presurgical BMI of 48.5 ± 6.5 kg/m2 (range 38.4-68.1 kg/m2). All procedures produced significant weight loss by 1 year, peak weight loss by 2 years, and modest weight regain after 5 years. Mean percent weight/BMI losses at 5 years for LRYGB, LAGB, and LSG were - 36.7 ± 10.8%, - 14.5 ± 15.3%, and - 25.1 ± 13.4%, respectively (p < 0.001). LRYGB patients were most likely to achieve ≥ 25% weight loss at 1, 3, and 5 years and maintained significant average weight loss for more than 15 years after surgery. Reoperations were procedure-specific, with LAGB, LRYGB, and LSG having the highest, middle, and lowest reoperation rates, respectively (40.9% vs. 16.9% vs. 5.4%, p < 0.001). CONCLUSION: All procedures provided significant and durable weight loss. LRYGB patients achieved the best and most sustained weight loss. LSG patients experienced second-best weight loss between 1 and 5 years, with lowest chance of reoperation. LAGB patients had the least weight loss and the highest reoperation rate. Compared to other factors, type of bariatric procedure was independently predictive of successful weight loss over time. More studies with long-term follow-up are needed.

Postmastectomy Breast Reconstruction Patterns at an Urban Academic Hospital and the Impact of Surgeon Gender.

BACKGROUND: Postmastectomy breast reconstruction is an essential element of multidisciplinary breast cancer care but may be underutilized. METHODS: This retrospective study analyzed mastectomy patients (2018-2021) at an urban hospital. Multivariable logistic regression was performed, and a mixed-effects logistic regression model was constructed to determine patient-level factors (age, race, body mass index, comorbidities, smoking status, insurance, type of surgery) and provider-level factors (breast surgeon gender, participation in multidisciplinary breast clinic) that influence reconstruction. RESULTS: Overall, 167 patients underwent mastectomy. The reconstruction rate was 35%. In multivariable analysis, increasing age (odds ratio [OR] 0.95; 95% confidence interval [CI] 0.91-0.99) and Medicaid insurance (OR 0.18; 95% CI 0.06-0.53) relative to private insurance were negative predictors, whereas bilateral mastectomy was a positive predictor (OR 7.07; 95% CI 2.95-17.9) of reconstruction. After adjustment for patent age, race, insurance, and type of surgery, female breast surgeons had 3.7 times greater odds of operating on patients who had reconstruction than males (95% CI 1.20-11.42). CONCLUSION: Both patient- and provider-level factors have an impact on postmastectomy reconstruction. Female breast surgeons had nearly four times the odds of caring for patients who underwent reconstruction, suggesting that a more standardized process for plastic surgery referral is needed.

Operative Shutdown and Recovery: Restructuring Surgical Operations During the SARS-CoV-2 Pandemic.

BACKGROUND: During the 2020 SARS-CoV-2 outbreak in New York City, hospitals canceled elective surgeries to increase capacity for critically ill patients. We present case volume data from our community hospital to demonstrate how this shutdown affected surgical care. METHODS: Between March 16 and June 14, 2020, all elective surgeries were canceled at our institution. All procedures performed during this operating room shutdown (ORS) were logged, as well as those 4 weeks before (PRE) and 4 weeks after (POST) for comparison. RESULTS: A total of 2,475 cases were included in our analysis, with 754 occurring during shutdown. Overall case numbers dropped significantly during ORS and increased during recovery (mean 245.0 ± 28.4 PRE versus 58.0 ± 30.9 ORS versus 186.0±19.4 POST cases/wk, P< 0.001). Emergency cases predominated during ORS (26.4% PRE versus 59.3% ORS versus 31.5% POST, P< 0.001) despite decreasing in frequency (mean 64.5 ± 7.9 PRE versus 34.4 ± 12.1 ORS versus 58.5 ± 4.0 POST cases/wk, P< 0.001). Open surgeries remained constant in all three phases (52.2-54.1%), whereas laparoscopic and robotic surgeries decreased (-3.4% and -3.0%, P< 0.001). General and/or vascular surgery, urology, and neurosurgery comprised a greater proportion of caseload (+9.5%, +3.0%, +2.8%), whereas orthopedics, gynecology, and otolaryngology/plastic surgery all decreased proportionally (-5.0%, -4.4%, -5.9%, P< 0.001). CONCLUSION: Operative volume significantly decreased during the SARS-CoV-2 outbreak. Emergency cases predominated during this time, although there were fewer emergency cases overall. General/vascular surgery became the most active service and open surgeries became more common. This reallocation of resources may be useful for future crisis planning among community hospitals.

Weight loss dynamics following laparoscopic Roux-en-Y gastric bypass. An analysis of 10-year follow-up data.

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGB) still remains the gold-standard bariatric procedure. Short-term weight loss and improvement of type 2 diabetes mellitus (DM2) after LRYGB are well-documented. Little data are available on long-term weight loss and continued remission of DM2 in these patients. METHODS: This study reports on weight loss and remission of DM2 in 576 consecutive patients who underwent primary LRYGB between August 2001 and August 2009 with at least 10-year follow up. All patients were treated at a single institution by a single surgeon. All data were collected and entered into the database prospectively. RESULTS: A total of 576 patients were included in the study. Patients' mean age was 38.2 ± 10.9 years and females represented 88.2% of patients. Patients' ethnicity was diverse, including African Americans (44.4%), Caucasians (34.0%), Hispanics (18.1%), and 3.5% from other backgrounds. On average, there were 6.9 ± 2.7 comorbidities per patient and DM2 was initially present in 150/576 patients (26.0%). Mean preoperative weight and BMI were 132.4 ± 22.0 kg and 48.3 ± 6.7 kg/m2, respectively. Ten-year follow-up reporting rate was 145/576 (25.2%). Maximum weight loss occurred at 18 months (mean weight 83.4 ± 16.5 kg, mean BMI 30.5 ± kg/m2). At 10 years, mean weight was maintained at 94.8 ± 20.5 kg and mean BMI was 34.3 ± 6.8 kg/m2. The average weight regain between one and ten years was 8.27 kg. Among patients with preoperative DM2, continued remission of DM2 at 10 years occurred in 19/32 (59.4%) patients. CONCLUSIONS: LRYGB provides durable long-term weight loss, as well as successful remission of DM2 at 10 years. More long-term follow-up studies evaluating weight loss and comorbidities extending beyond the initial 10-year period are needed. Such studies are essential for projecting late outcomes of LRYGB, particularly in younger patients with life expectancy exceeding several decades.

Laparoscopic-guided transversus abdominis plane block following laparoscopic sleeve gastrectomy is associated with an earlier return to activity: a study of 271 patients.

BACKGROUND: The morbidly obese (MO) patient presents a unique challenge to pain control in the postoperative period due to associated comorbidities and the amplified impact of opiates. In order to reduce potential complications associated with narcotic use in the MO patient, multimodal analgesia has been advocated. In this study, we examined the effect of laparoscopic-guided transversus abdominis plane block (LG TAP) for further optimizing multimodal pain control. METHODS: This is a retrospective analysis of a prospectively collected database of 140 consecutive patients undergoing LSG without TAP block (pre-TAP group) compared to 131 patients undergoing LSG with LGTAP (TAP group). All operations were performed laparoscopically utilizing uniform clinical pathways. Baseline characteristics for both groups were comparable. Both groups received standardized anesthesia. Outcomes included time to postoperative ambulation, pain scores, PCA volume, length of hospital stay, utilization of oral opiate medications, and return to activity (RTA). RESULTS: Pre-TAP versus TAP groups were comparable, mean age 42 years (p = 0.99), women 81.4% versus 87.8% (p = 0.148), mean BMI (kg/m2) 46 versus 45 (p = 0.394). Most patients ambulated within 2 h after arrival to the floor (87.9% vs. 76.3%, p = 0.013). On postoperative day (POD) 1, mean reported pain score (0-10) was 4.50 vs. 5.06 (p = 0.063) and a mean PCA morphine used for 24 h was 26.3 mL versus 26 mL, p = 0.35. Mean days of postoperative opiate medication were 2.19 versus 1.24 (p < 0.001). Return to activity was 2.81 versus 2.08 days (p < 0.001). When controlled for age, BMI, OR time, PCA volume used, and average pain score, TAP block was an independent predictor of earlier return to activities (p < 0.001). CONCLUSIONS: LGTAP block following LSG is an additional valuable modality of pain control in the perioperative period. Our study shows that TAP block is associated with an earlier RTA and decreased opiate use in patients undergoing LSG.

Assessment of Endoscope Reprocessing Using Peer-to-Peer Assessment Through a Clinical Community.

BACKGROUND: Cleaning, disinfection, and sterilization (CDS) of medical devices are intended to help prevent health care-associated infections (HAIs), a significant cause of mortality and morbidity. In February 2013 the Johns Hopkins Health System (JHHS; Baltimore) formed a clinical community of experts and stakeholders--physicians, nurses, administrators, infection control practitioners, risk managers, and regulatory staff--to assess CDS practices across facilities. METHODS: A survey administered to leadership indicated endoscopy areas of risk. An endoscopy tracer tool with eight major performance areas was then created from best practices identified in the literature, regulatory requirements, and national guidelines for endoscope reprocessing. Peer-to-peer (P2P) assessments using the tracer tool were performed at five Johns Hopkins Medicine gastrointestinal endoscopy sites (three hospital-based; two freestanding ambulatory surgery centers) selected on the basis of their large procedural volumes and their operational ability to participate in further areas of the project. RESULTS: The P2P assessments revealed that 20 (42%) of the 48 possible criteria had a noted deficiency at one or more sites. Three of the eight major performance areas on the tracer tool had no deficiencies identified at any of the five sites. Deficiencies were mostly minor process improvements, and only one critical process required immediate alteration of practice. Because the assessments were nonpunitive, horizontal communication enabled feedback on process improvements, alternate methods to achieve outcomes, and solutions to common issues. CONCLUSIONS: A nonpunitive and collaborative peer methodology was successful in capturing and sharing best practices in endoscopy areas. Successful replication in other clinical areas can be an effective way to assess CDS processes and facilitate dialogue for improvements.

Prevalence of surgical conditions in individuals aged more than 50 years: a cluster-based household survey in Sierra Leone.

BACKGROUND: With the demographic transition disproportionately affecting developing nations, the healthcare burden associated with the elderly is likely to be compounded by poor baseline surgical capacity in these settings. We sought to assess the prevalence of surgical disease and disability in the elderly population of Sierra Leone to guide future development strategies. METHODS: A cluster randomized, cross-sectional household survey was carried out countrywide in Sierra Leone from January 9th to February 3rd 2012. Using a standardized questionnaire, household member demographics, deaths occurring during the previous 12 months, and presence of any current surgical condition were elucidated. A retrospective analysis of individuals aged 50 and over was performed. RESULTS: The survey included 1,843 households with a total of 3,645 respondents. Of these, 13.6 % (496/3,645) were aged over 50 years. Of the elderly individuals in our sample, 301 (60.7 %) reported a current surgical condition. Of current surgical disease identified among elderly individuals (n = 530), 349 (65.8 %) described it as disabling, and 223 (42.1 %) sought help from traditional medicine practitioners. Women (odds ratio [OR] 0.60; 95 % confidence interval [CI] 0.40-0.90) and individuals living in urban settings (OR 0.44, 95 % CI 0.26-0.75) were less likely to report a current surgical problem. Of the 230 elderly deaths in the previous year, 83 (36.1 %) reported a surgical condition in the week prior. CONCLUSIONS: The unmet burden of surgical disease is prevalent in the elderly in low-resource settings. This patient population is expected to grow significantly in the coming years, and more resources should be allocated to address their surgical needs.

Clinical Communities at Johns Hopkins Medicine: An Emerging Approach to Quality Improvement.

BACKGROUND: Clinical communities are an emerging approach to quality improvement (QI) to which several large-scale projects have attributed some success. In 2011 the Armstrong Institute for Patient Safety and Quality established clinical communities as a core strategy to connect frontline providers from six different hospitals to improve quality of care, patient safety, and value across the health system. CLINICAL COMMUNITIES: Fourteen clinical communities that presented great opportunity for improvement were established. A community could focus on a clinical area, a patient population, a group, a process, a safety-related issue, or nearly any health care issue. The collaborative spirit of the communities embraced interdisciplinary membership and representation from each hospital in each community. Communities engaged in team-building activities and facilitated discussions, met monthly, and were encouraged to meet in person to develop relationships and build trust. After a community was established, patients and families were invited to join and share their perspectives and experiences. ENABLING STRUCTURES: The clinical community structure provided clinicians access to resources, such as technical experts and safety and QI researchers, that were not easily otherwise accessible or available. Communities convened clinicians from each hospital to consider safety problems and their resolution and share learning with workplace peers and local unit safety teams. CONCLUSION: The clinical communities engaged 195 clinicians from across the health system in QI projects and peer learning. Challenges included limited financial support and time for clinicians, timely access to data, limited resources from the health system, and not enough time with improvement experts.

Anticancer peptide PNC-27 adopts an HDM-2-binding conformation and kills cancer cells by binding to HDM-2 in their membranes.

The anticancer peptide PNC-27, which contains an HDM-2-binding domain corresponding to residues 12-26 of p53 and a transmembrane-penetrating domain, has been found to kill cancer cells (but not normal cells) by inducing membranolysis. We find that our previously determined 3D structure of the p53 residues of PNC-27 is directly superimposable on the structure for the same residues bound to HDM-2, suggesting that the peptide may target HDM-2 in the membranes of cancer cells. We now find significant levels of HDM-2 in the membranes of a variety of cancer cells but not in the membranes of several untransformed cell lines. In colocalization experiments, we find that PNC-27 binds to cell membrane-bound HDM-2. We further transfected a plasmid expressing full-length HDM-2 with a membrane-localization signal into untransformed MCF-10-2A cells not susceptible to PNC-27 and found that these cells expressing full-length HDM-2 on their cell surface became susceptible to PNC-27. We conclude that PNC-27 targets HDM-2 in the membranes of cancer cells, allowing it to induce membranolysis of these cells selectively.

Implementation of robotic surgery in Dubai: a focus on outcomes.

The rapid acceptance of robotic surgery in gallbladder, inguinal, and ventral hernia surgery has led to the growth of robotic surgery programs around the world. As this is new technology, implementation of such programs needs to be done safely, with a focus on patient outcomes. We herein describe the implementation of a new robotic surgery program in a major hospital in the Middle East. A laparoendoscopic surgeon led the program after training and proctoring. Competency based credentialing were created and put in place. To confirm safety of the program, all laparoscopic and robotic cholecystectomy and hernia operations were followed, and perioperative data analyzed. Out of the 304 patients included in this study, 157 were performed using the robotic approach. In the cholecystectomy group (n = 103) the single site approach offered shorter operative times (P < 0.05). Both the single site robotic and the robotic assisted approaches resulted in less pain (P < 0.05). In the inguinal hernia group (n = 146) the laparoscopic approach offered shorter operative times (P < 0.05), but the robotic approach was associated with less pain (P < 0.05). In the ventral hernia group (n = 55), the open approach offered the best operative times, but the robotic approach was associated with the least amount of pain (P < 0.05). This is the first report of the implementation of a robotic program in the MENA region where the primary measure of success is outcomes. We show that monitoring cholecystectomy, inguinal or ventral hernia data can confirm the quality of the program before expansion and moving forward to more complex procedures.

Initial experience with a novel robotic surgical system in abdominal surgery.

The emergence of robotics in surgery has led to a recent boom in the acceptance of such technology. This technology has been rapidly adopted in various fields, with the most prominent being general surgery. The number of abdominal procedures being performed using robotics has increased to around 15.1% as potential advantages continue to be highlighted. We herein report the use of the Versius surgical robotic system for use in common abdominal procedures. Three experienced robotic surgeons first gained experience and became familiar with the robotic system through both online modules and cadaveric training sessions. The initial cases performed using the Versius robotic system at a single center were included in this study. Data reported included demographics as well as perioperative data. Fifty-five procedures were performed using the Versius robotic system. Procedures included various hernia repairs (n = 30), gallbladder surgery (n = 22), as well as appendix surgery (n = 3). Appendectomy had the fastest OR times at 35.81 ± 21.84, while the slowest OR times were seen in the BIH group with an average time of 95.2 ± 24. No complications or conversions were observed throughout this entire series. This is the first report to demonstrate the usage of the Versius robotic surgical system for use in abdominal surgery. Our initial data confirm that regardless of patient demographics, the system is safe to use in such procedures; however, further larger scale studies are required to assess its clinical utility.

Treatment of an unusual case of Meckel's diverticulum with a new robotic platform.

INTRODUCTION AND IMPORTANCE: Meckel's diverticulum (MD) is a common congenital anomaly of the digestive tract that affects around 4 % of the population. Although it is relatively common, diagnosis still remains very challenging; it requires an astute clinician with a high clinical index of suspicion to achieve the diagnosis. Once a diagnosis is reached, treatment is almost always surgical. This case report provides evidence of the effectiveness of a new robotic surgical system for resection of MD in the elderly. CASE PRESENTATION: 61 year old male presented to the emergency room with recurrent hematochezia. After multiple diagnostic techniques, he was finally diagnosed with MD using Meckel's scan. After diagnosis, surgical resection using the Cambridge Medical Robotics (CMR) Versius robotic system was performed, which yielded good results. CLINICAL DISCUSSION: This case highlights the use of a new robotic system for the treatment of Meckel's Diverticulum. CONCLUSION: Our initial experience with the CMR Versius surgical system in small bowel resection was successful; however, further studies are needed to demonstrate the safety and efficacy of such a system.

Blueprint for safe transition from a low- to high-volume pancreatic surgery center.

We describe a straightforward model to implement a high volume specialty surgery program at a community hospital. Using pancreatic surgery as an example, we employed published processes in three arenas. First, mandatory multidisciplinary tumor board presentations captured all the patients considered for surgery. Then, perioperative protocols using tools such as enhanced recovery and teamwork in the perioperative arena created a reproducible and safe environment for complex surgery. We critically reviewed all complications using the Clavien-Dindo methodology, and confirmed our favorable outcomes via the targeted NSQIP program. These standard steps can be used for implementation of a new complex surgical procedure.

Utility of d-dimer for diagnosis of deep vein thrombosis in coronavirus disease-19 infection.

OBJECTIVE: The objective of this study was to investigate the clinical usefulness of d-dimer in excluding a diagnosis of deep vein thrombosis (DVT) in patients with coronavirus disease (COVID-19) infection, potentially limiting the need for venous duplex ultrasound examination. METHODS: We retrospectively reviewed consecutive patients admitted to our institution with confirmed COVID-19 status by polymerase chain reaction between March 1, 2020, and May 13, 2020, and selected those who underwent both d-dimer and venous duplex ultrasound examination. This cohort was divided into two groups, those with and without DVT based on duplex ultrasound examination. These groups were then compared to determine the value of d-dimer in establishing this diagnosis. RESULTS: A total of 1170 patients were admitted with COVID-19, of which 158 were selected for this study. Of the 158, there were 52 patients with DVT and 106 without DVT. There were no differences in sex, age, race, or ethnicity between groups. Diabetes and routine hemodialysis were less commonly seen in the group with DVT. More than 90% of patients in both groups received prophylactic anticoagulation, but the use of low-molecular-weight heparin or subcutaneous heparin prophylaxis was not predictive of DVT. All patients had elevated acute-phase d-dimer levels using conventional criteria, and 154 of the 158 (97.5%) had elevated levels with age-adjusted criteria (mean d-dimer 16,163 ± 5395 ng/mL). Those with DVT had higher acute-phase d-dimer levels than those without DVT (median, 13,602 [interquartile range, 6616-36,543 ng/mL] vs 2880 [interquartile range, 1030-9126 ng/mL], P < .001). An optimal d-dimer cutoff of 6494 ng/mL was determined to differentiate those with and without DVT (sensitivity 80.8%, specificity 68.9%, negative predictive value 88.0%). Wells DVT criteria was not found to be a significant predictor of DVT. Elevated d-dimer as defined by our optimal metric was a statistically significant predictor of DVT in both univariate and multivariable analyses when adjusting for other factors (odds ratio, 6.12; 95% confidence interval, 2.79-13.39; P < .001). CONCLUSIONS: d-dimer levels are uniformly elevated in patients with COVID-19. Although standard predictive criteria failed to predict DVT, our analysis showed a d-dimer of less than 6494 ng/mL may exclude DVT, potentially limiting the need for venous duplex ultrasound examination.

Comparison of His and GST tagged versions of recombinant pancreatitis associated protein 2 in modulation of inflammatory responses.

OBJECTIVE AND DESIGN: Pancreatitis associated proteins (PAP) are highly upregulated in acute pancreatitis and other inflammatory states and have been shown to possess immunomodulatory properties. However, continued study of PAP has been hampered by the ability to effectively isolate appropriate amounts of protein from pancreatic juice or efficient generation of recombinant proteins. Here we describe two different methods for generating recombinant PAP2 protein (rPAP2), using either His or GST tagged bacterial methodology with comparison of function. METHODS: His or GST tagged rPAP2 were generated, cultured with clonal (NR8383) macrophages and compared with respect to inflammatory cytokine expression (IL-1alpha, IL-1beta, IL-6, and TNF-alpha) and bacterial (E. coli) agglutination. Significance was determined by student's t test (P<0.05). RESULTS: PAP2His treatment induced a 3.6, 2.8, 13.0, 3.5 fold induction of IL-1alpha, IL-1beta, TNF-alpha and IL-6, respectively; similar cytokine expression changes were observed with PAP2GST treatment (3.9, 2.6, 12.2, and 3.0 fold induction of IL-1alpha, IL-1beta, TNF-alpha and IL-6, respectively) (P<0.05). Further, incubation with recombinant PAP2 led to a time dependent increase in bacterial aggregates which was absent in controls. CONCLUSIONS: These data demonstrate that both methods maintain functional immunomodulatory integrity for PAP2 and provide the ability to generate sufficient quantities to further study structure and function.

Mutational characterization of pancreatitis-associated protein 2 domains involved in mediating cytokine secretion in macrophages and the NF-kappaB pathway.

Pancreatitis-associated protein 2 (PAP2) is a member of the Reg3 gene family and is classified as a group 7 C-type lectin-like protein. In rats, each of the three PAP isoforms has independent immunologic functional effects on macrophages. We have previously shown that PAP2 up-regulates inflammatory cytokines in macrophages in a dose-dependent manner and acts through NF-kappaB mechanisms. In this study, we aimed to determine protein domains that are essential for the immunologic function of PAP2 by mutational or chemical analysis. The protein activity for each mutant was determined by measuring TNF-alpha, IL-6, or IL-1 production in macrophages. Truncation of the first 25 residues on the N terminus of PAP2 did not affect protein activity whereas truncation of the last 30 residues of the C terminus of PAP2 completely inactivated the function of PAP2. Additionally, reduction of three disulfide bonds proved to be important for the activity of this protein. Further investigation revealed two invariant disulfide bonds were important for activity of PAP2 while the disulfide bond that is observed in long-form C-type lectin proteins was not essential for activity. Coupling the ability of PAP2 to up-regulate inflammatory cytokines via NF-kappaB with its associated expression in acute pancreatitis, a condition with aberrant concentrations of inflammatory cytokines, we investigated whether PAP2 mutants mechanistically activate the NF-kappaB-signaling pathway and demonstrate that preincubation with select rPAP2 mutant proteins affect translocation of this transcription factor into the nucleus.