Preoperative anaemia in distal pancreatectomy: a propensity-score matched analysis

BACKGROUND

Preoperative anaemia is a prevalent morbidity predictor that adversely affects short- and long-term outcomes of patients undergoing surgery. This analysis aimed to investigate preoperative anaemia and its detrimental effects on patients after distal pancreatectomy.

MATERIAL AND METHODS

The present study was a propensity-score match analysis of 286 consecutive patients undergoing distal pancreatectomy. Patients were screened for preoperative anaemia and classified according to WHO recommendations. The primary outcome measure was overall morbidity. The secondary endpoints were in-hospital mortality and rehospitalization.

RESULTS

The preoperative anaemia rate before matching was 34.3% (98 patients), and after matching a total of 127 patients (non-anaemic 42 vs. anaemic 85) were included. Anaemic patients had significantly more postoperative major complications (54.1% vs. 23.8%; p < 0.01), a higher comprehensive complication index (26.2 vs. 4.3; p < 0.01), and higher in-hospital mortality rate (14.1% vs. 2.4%; p = 0.04). Multivariate regression analysis confirmed these findings and identified preoperative anaemia as a strong independent risk factor for postoperative major morbidity (OR 4.047; 95% CI: 1.587-10.320; p < 0.01).

CONCLUSION

The current propensity-score matched analysis strongly considered preoperative anaemia as a risk factor for major complications following distal pancreatectomy. Therefore, an intense preoperative anaemia workup should be increasingly prioritised.

Textbook outcome after pancreatoduodenectomy and distal pancreatectomy with postoperative hyperamylasemia-a propensity score matching analysis

PURPOSE

Postoperative serum hyperamylasemia (POH) is a part of the new, increasingly highlighted, definition for postpancreatectomy pancreatitis (PPAP). This study aimed to analyze whether the biochemical changes of PPAP are differently associated with postoperative complications after distal pancreatectomy (DP) compared with pancreatoduodenectomy (PD). The textbook outcome (TO) was used as a summary measure to capture real-world data.

METHODS

The data were retrospectively extracted from a prospective clinical database. Patients with POH, defined as levels above our institution's upper limit of normal on postoperative day 1, after DP and the corresponding propensity score-matched cohort after PD were evaluated on postoperative complications by using logistic regression analyses.

RESULTS

We analyzed 723 patients who underwent PD and DP over a period of 9 years. After propensity score matching, 384 patients (192 patients in each group) remained. POH was observed in 78 (41.1%) and 74 (39.4%) after PD and DP correspondingly. There was a significant increase of postoperative complications in the PD group: Clavien-Dindo classification system ≥3 (P < .01 vs P = .71), clinically relevant postoperative pancreatic fistula (P < .001 vs P = .2), postpancreatectomy hemorrhage (P < .001 vs P = .11), and length of hospital stay (P < .001 vs P = .69) if POH occurred compared with in the DP group. TO was significantly unlikely in cases with POH after PD compared with DP (P > .001 vs P = .41). Furthermore, POH was found to be an independent predictor for missing TO after PD (odds ratio [OR], 0.29; 95% CI, 0.14-0.60; P < .001), whereas this was not observed in patients after DP (OR, 0.53; 95% CI, 0.21-1.33; P = .18).

CONCLUSION

As a part of the definition for PPAP, POH is a predictive indicator associated with postoperative complications after PD but not after DP.

Preoperative IL-8 levels as prognostic indicators of overall survival: an extended follow-up in a prospective cohort with colorectal liver metastases

INTRODUCTION

CRC with liver metastases is a major contributor to cancer-related mortality. Despite advancements in liver resection techniques, patient survival remains a concern due to high recurrence rates. This study seeks to uncover prognostic biomarkers that predict overall survival in patients undergoing curative hepatic resection for CRC liver metastases.

METHODS

Prospectively collected serum samples from a cohort of 49 patients who received curative hepatic resection for CRC liver metastases were studied. The patients are part of a cohort, previously analyzed for perioperative complications (see methods). Various preoperative serum markers, clinical characteristics, and factors were analyzed. Univariate and multivariate Cox regression analyses were conducted to determine associations between these variables and disease-free survival as well as overall survival.

RESULTS

For disease-free survival, univariate analysis highlighted the correlation between poor outcomes and advanced primary tumor stage, high ASA score, and synchronous liver metastases. Multivariate analysis identified nodal-positive primary tumors and synchronous metastases as independent risk factors for disease-free survival. Regarding overall survival, univariate analysis demonstrated significant links between poor survival and high preoperative IL-8 levels, elevated neutrophil-lymphocyte ratio (NLR), and presence of metastases in other organs. Multivariate analysis confirmed preoperative IL-8 and having three or more liver metastases as independent risk factors for overall survival. The impact of IL-8 on survival was particularly noteworthy, surpassing the influence of established clinical factors.

CONCLUSION

This study establishes preoperative IL-8 levels as a potential prognostic biomarker for overall survival in patients undergoing curative liver resection for CRC liver metastases. This study underscores the importance of incorporating IL-8 and other biomarkers into clinical decision-making, facilitating improved patient stratification and tailored treatment approaches. Further research and validation studies are needed to solidify the clinical utility of IL-8 as a prognostic marker.

Development and Validation of a Model for Postpancreatectomy Hemorrhage Risk

Importance

Postpancreatectomy hemorrhage (PPH) due to postoperative pancreatic fistula (POPF) is a life-threatening complication after pancreatoduodenectomy. However, there is no prediction tool for early identification of patients at high risk of late PPH.

Objective

To develop and validate a prediction model for PPH.

Design, Setting, and Participants

This retrospective prognostic study included consecutive patients with clinically relevant POPF who underwent pancreatoduodenectomy from January 1, 2009, to May 20, 2023, at the University Hospital Mannheim (derivation cohort), and from January 1, 2012, to May 31, 2022, at the University Hospital Dresden (validation cohort). Data analysis was performed from May 30 to July 29, 2023.

Exposure

Clinical and radiologic features of PPH.

Main Outcomes and Measures

Accuracy of a predictive risk score of PPH. A multivariate prediction model-the hemorrhage risk score (HRS)-was established in the derivation cohort (n = 139) and validated in the validation cohort (n = 154).

Results

A total of 293 patients (187 [64%] men; median age, 69 [IQR, 60-76] years) were included. The HRS comprised 4 variables with associations: sentinel bleeding (odds ratio [OR], 35.10; 95% CI, 5.58-221.00; P < .001), drain fluid culture positive for Candida species (OR, 14.40; 95% CI, 2.24-92.20; P < .001), and radiologic proof of rim enhancement of (OR, 12.00; 95% CI, 2.08-69.50; P = .006) or gas within (OR, 12.10; 95% CI, 2.22-65.50; P = .004) a peripancreatic fluid collection. Two risk categories were identified with patients at low risk (0-1 points) and high risk (≥2 points) to develop PPH. Patients with PPH were predicted accurately in the derivation cohort (C index, 0.97) and validation cohort (C index 0.83). The need for more invasive PPH management (74% vs 34%; P < .001) and severe complications (49% vs 23%; P < .001) were more frequent in high-risk patients compared with low-risk patients.

Conclusions and Relevance

In this retrospective prognostic study, a robust prediction model for PPH was developed and validated. This tool may facilitate early identification of patients at high risk for PPH.

Systematic Review and Meta-analysis of the Role of Total Pancreatectomy as an Alternative to Pancreatoduodenectomy in Patients at High Risk for Postoperative Pancreatic Fistula: Is it a Justifiable Indication?

OBJECTIVE

Examine the potential benefit of total pancreatectomy (TP) as an alternative to pancreatoduodenectomy (PD) in patients at high risk for postoperative pancreatic fistula (POPF).

SUMMARY BACKGROUND DATA

TP is mentioned as an alternative to PD in patients at high risk for POPF, but a systematic review is lacking.

METHODS

Systematic review and meta-analyses using Pubmed, Embase (Ovid), and Cochrane Library to identify studies published up to October 2022, comparing elective single-stage TP for any indication versus PD in patients at high risk for POPF. The primary endpoint was short-term mortality. Secondary endpoints were major morbidity (i.e., Clavien-Dindo grade ≥IIIa) on the short-term and quality of life.

RESULTS

After screening 1212 unique records, five studies with 707 patients (334 TP and 373 high-risk PD) met the eligibility criteria, comprising one randomized controlled trial and four observational studies. The 90-day mortality after TP and PD did not differ (6.3% vs. 6.2%; RR=1.04 [95%CI 0.56-1.93]). Major morbidity rate was lower after TP compared to PD (26.7% vs. 38.3%; RR=0.65 [95%CI 0.48-0.89]), but no significance was seen in matched/randomized studies (29.0% vs. 36.9%; RR = 0.73 [95%CI 0.48-1.10]). Two studies investigated quality of life (EORTC QLQ-C30) at a median of 30-52 months, demonstrating comparable global health status after TP and PD (77% [±15] vs. 76% [±20]; P =0.857).

CONCLUSIONS

This systematic review and meta-analysis found no reduction in short-term mortality and major morbidity after TP as compared to PD in patients at high risk for POPF. However, if TP is used as a bail-out procedure, the comparable long-term quality of life is reassuring.

RAB27B expression in pancreatic cancer is predictive of poor survival but good response to chemotherapy

BACKGROUND

Pancreatic cancer is the 4th leading cause of cancer-related death with poor survival even after curative resection. RAB27A and RAB27B are key players in the exosome pathway where they play important roles in exosome secretion. Evidence suggests that RAB27A and RAB27B expression not only leads to tumor proliferation and invasion, but also plays an important role in antigen transfer necessary for anticancer immunity.

OBJECTIVE

In this study, we analyze the expression of RAB27A and RAB27B in patients after pancreatic cancer surgery with or without adjuvant chemotherapy and its influence on overall survival.

METHODS

We analyzed a total of 167 patients with pancreatic cancer for their RAB27A and RAB27B expression. We dichotomized the patients along the median and compared survival in patients with high and low RAB27A and RAB27B expression with or without adjuvant chemotherapy treatment.

RESULTS

We found a significant improvement in overall survival in patients with a negative resection margin (p= 0.037) and in patients who received adjuvant chemotherapy (p= 0.039). The survival benefit after chemotherapy was dependent on RAB27B expression status: only the subgroup of patients with high RAB27B expression benefited from adjuvant chemotherapy (p= 0.006), but not the subgroup with low RAB27B expression (p= 0.59). Patients with high RAB27B expression who did not receive adjuvant chemotherapy showed a trend towards worse survival compared to the other subgroups. This difference was abolished after treatment with adjuvant chemotherapy.

CONCLUSION

These results suggest that RAB27B expression in pancreatic cancer might identify a subgroup of patients with poor survival who might respond well to adjuvant chemotherapy. If resectable, these patients could be considered for neoadjuvant chemotherapy to minimize the risk of not receiving adjuvant chemotherapy. Further prospective studies are needed to confirm these findings.

[Highlights of pancreatic surgery: extended indications in pancreatic neuroendocrine tumors]

Advanced pancreatic neuroendocrine tumors (paNET) are mostly characterized by infiltration of vascular structures and/or neighboring organs. The indications for resection in these cases should be measured based on the possibility of an R0 resection. Although the data situation for this rare entity is limited, small case series have shown a significant survival advantage in patients who underwent a radical resection in locally advanced stages of paNET. Both vascular reconstruction and multivisceral resection, when performed at experienced centers, should be considered as curative treatment options. The very special biological behavior of the paNET and the often young patient age justify a much more aggressive approach compared to the pancreatic ductal adenocarcinoma.

Quality of life and metabolic outcomes after total pancreatectomy and simultaneous islet autotransplantation

Background

Pancreas surgery remains technically challenging and is associated with considerable morbidity and mortality. Identification of predictive risk factors for complications have led to a stratified surgical approach and postoperative management. The option of simultaneous islet autotransplantation (sIAT) allows for significant attenuation of long-term metabolic and overall complications and improvement of quality of life (QoL). The potential of sIAT to stratify a priori the indication for total pancreatectomy is yet not adequately evaluated.

Methods

The aim of this analysis was to evaluate the potential of sIAT in patients undergoing total pancreatectomy to improve QoL, functional and overall outcome and therefore modify the surgical strategy towards earlier and extended indications. A center cohort of 24 patients undergoing pancreatectomy were simultaneously treated with IAT. Patients were retrospectively analyzed regarding in-hospital and overall mortality, postoperative complications, ICU stay, hospital stay, metabolic outcome, and QoL.

Results

Here we present that all patients undergoing primary total pancreatectomy or surviving complicated two-stage pancreas resection and receiving sIAT show excellent metabolic outcome (33% insulin independence, 66% partial graft function; HbA1c 6,1 ± 1,0%) and significant benefit regarding QoL. Primary total pancreatectomy leads to significantly improved overall outcome and a significant reduction in ICU- and hospital stay compared to a two-stage completion pancreatectomy approach.

Conclusions

The findings emphasize the importance of risk-stratified pancreas surgery. Feasibility of sIAT should govern the indication for primary total pancreatectomy particularly in high-risk patients. In rescue completion pancreatectomy sIAT should be performed whenever possible due to tremendous metabolic benefit and associated QoL.

Pancreas surgery is complicated and associated with substantial risks and even danger of death. The surgical removal of the whole pancreas can be necessary for some indications but results in a severe form of diabetes. The method of islet autotransplantation (IAT) involves taking the pancreas, isolating the insulin-producing cells and returning these to the patient. This helps to preserve insulin production and minimises the impact of diabetes. We retrospectively analyzed a cohort of patients undergoing pancreatectomy that were simultaneously treated with IAT. The analysis included short-term and long-term surgical and diabetes-related outcomes as well as quality of life. All parameters indicated the benefit of IAT in patients that require extensive pancreas surgery. Offering IAT to patients may reduce surgical complications after pancreatectomy, enhance recovery, and therefore facilitate faster initiation of other therapies where needed.

Ludwig and Distler et al. evaluate quality of life and metabolic outcomes in patients undergoing total pancreatectomy and simultaneous islet autotransplantation. The authors report benefits in terms of glycemic control, as well as improvements in quality of life, following the procedure.

The Impact of Pancreatic Head Resection on Blood Glucose Homeostasis in Patients with Chronic Pancreatitis

BACKGROUND

Chronic pancreatitis (CP) often leads to recurrent pain as well as exocrine and/or endocrine pancreatic insufficiency. This study aimed to investigate the effect of pancreatic head resections on glucose metabolism in patients with CP.

METHODS

Patients who underwent pylorus-preserving pancreaticoduodenectomy (PPPD), Whipple procedure (cPD), or duodenum-preserving pancreatic head resection (DPPHR) for CP between January 2011 and December 2020 were retrospectively analyzed with regard to markers of pancreatic endocrine function including steady-state beta cell function (%B), insulin resistance (IR), and insulin sensitivity (%S) according to the updated Homeostasis Model Assessment (HOMA2).

RESULTS

Out of 141 pancreatic resections for CP, 43 cases including 31 PPPD, 2 cPD and 10 DPPHR, met the inclusion criteria. Preoperatively, six patients (14%) were normoglycemic (NG), 10 patients (23.2%) had impaired glucose tolerance (IGT) and 27 patients (62.8%) had diabetes mellitus (DM). In each subgroup, no significant changes were observed for HOMA2-%B (NG: p = 0.57; IGT: p = 0.38; DM: p = 0.1), HOMA2-IR (NG: p = 0.41; IGT: p = 0.61; DM: p = 0.18) or HOMA2-%S (NG: p = 0.44; IGT: p = 0.52; DM: p = 0.51) 3 and 12 months after surgery, respectively.

CONCLUSION

Pancreatic head resections for CP, including DPPHR and pancreatoduodenectomies, do not significantly affect glucose metabolism within a follow-up period of 12 months.

Short-term preoperative drainage is associated with improved postoperative outcomes compared to that of long-term biliary drainage in pancreatic surgery

Purpose

The treatment of choice for patients presenting with obstructive cholestasis due to periampullary carcinoma is oncologic resection without preoperative biliary drainage (PBD). However, resection without PBD becomes virtually impossible in patients with obstructive cholangitis or severely impaired liver cell function. The appropriate duration of drainage by PBD has not yet been defined for these patients.

Methods

A retrospective analysis was conducted on 170 patients scheduled for pancreatic resection following biliary drainage between January 2012 and June 2018 at the University Hospital Dresden in Germany. All patients were deemed eligible for inclusion, regardless of the underlying disease entity. The primary endpoint analysis was defined as the overall morbidity (according to the Clavien-Dindo classification). Secondary endpoints were the in-hospital mortality and malignancy adjusted overall and recurrence-free survival rates.

Results

A total of 170 patients were included, of which 45 (26.5%) and 125 (73.5%) were assigned to the short-term (< 4 weeks) and long-term (≥ 4 weeks) preoperative drainage groups, respectively.

Surgical complications (Clavien-Dindo classification > 2) occurred in 80 (47.1%) patients, with significantly fewer complications observed in the short-term drainage group (31.1% vs. 52%; p = 0.02). We found that long-term preoperative drainage (unadjusted OR, 3.386; 95% CI, 1.507–7.606; p < 0.01) and periampullary carcinoma (unadjusted OR, 5.519; 95% CI, 1.722–17.685; p-value < 0.01) were independent risk factors for postoperative morbidity, based on the results of a multivariate regression model. The adjusted overall and recurrence-free survival did not differ between the groups (p = 0.12).

Conclusion

PBD in patients scheduled for pancreatic surgery is associated with substantial perioperative morbidity. Our results indicate that patients who have undergone PBD should be operated on within 4 weeks after drainage.

Influence of the First Wave of the COVID-19 Pandemic on Cancer Care in a German Comprehensive Cancer Center

Introduction: During the first wave of the COVID-19 pandemic in 2020, the German government implemented legal restrictions to avoid the overloading of intensive care units by patients with COVID-19. The influence of these effects on diagnosis and treatment of cancer in Germany is largely unknown. Methods: To evaluate the effect of the first wave of the COVID-19 pandemic on tumor board presentations in a high-volume tertiary referral center (the German Comprehensive Cancer Center NCT/UCC Dresden), we compared the number of presentations of gastrointestinal tumors stratified by tumor entity, tumor stage, and treatment intention during the pandemic to the respective data from previous years. Results: The number of presentations decreased by 3.2% (95% CI -8.8, 2.7) during the COVID year 2020 compared with the pre-COVID year 2019. During the first shutdown, March-May 2020, the total number of presentations was 9.4% (-18.7, 1) less than during March-May 2019. This decrease was significant for curable cases of esophageal cancer [N = 37, 25.5% (-41.8, -4.4)] and colon cancer [N = 36, 17.5% (-32.6, 1.1)] as well as for all cases of biliary tract cancer [N = 26, 50% (-69.9, -15)] during the first shutdown from March 2020 to May 2020. Conclusion: The impact of the COVID-19 pandemic on the presentation of oncological patients in a CCC in Germany was considerable and should be taken into account when making decisions regarding future pandemics.

Perioperative Blood Management of Preoperative Anemia Determines Long-Term Outcome in Patients with Pancreatic Surgery

BACKGROUND/PURPOSE

Anemia affects the postoperative course of patients undergoing a major surgical procedure. However, it remains unclear whether anemia has a different impact on the long-term outcome of patients with malignant or benign pancreatic disease.

METHODS

A retrospective analysis of patients undergoing pancreatic surgery for pancreatic malignancies or chronic pancreatitis was conducted between January 2012 and June 2018 at the University Hospital Dresden, Germany. The occurrence of preoperative anemia and the administration of pre-, intra-, and postoperative blood transfusions were correlated with postoperative complications and survival data by uni- and multivariate analysis.

RESULTS

A total of 682 patients were included with 482 (70.7%) undergoing surgical procedures for pancreatic malignancies. Univariate regression analysis confirmed preoperative anemia as a risk factor for postoperative complications > grade 2 according to the Clavien-Dindo classification. Multivariate regression analyses indicated postoperative blood transfusion as an independent risk factor for postoperative complications in patients with a benign (OR 20.5; p value < 0.001) and a malignant pancreatic lesion (OR 4.7; p value < 0.01). Univariate and multivariate analysis revealed preoperative anemia and pre-, intra-, and postoperative blood transfusions as independent prognostic factors for shorter overall survival in benign and malignant patients (p value < 0.001-0.01).

CONCLUSION

Preoperative anemia is a prevalent, independent, and adjustable factor in pancreatic surgery, which poses a significant risk for postoperative complications irrespective of the entity of the underlying disease. It should therefore be understood as an adjustable factor rather than an indicator of underlying disease severity.

Spleno-aortic radiodensity ratio - A distinctive imaging feature to predict short-term outcome in critical care unit

INTRODUCTION

To investigate the value of contrast-enhanced CT findings - splenic and aortic radiodensities and their ratios (spleno-aortic ratio) - in predicting the prognosis of critical care unit patients (CCU).

METHODS

One hundred thirteen continuous CCU patients with an acute deterioration (Group A: 37 women, age: 67.2 ± 14.0 years) were included in the retrospective study. Radiodensities of the spleen and aorta were evaluated by two radiologists separately. The spleno-aortic ratio was calculated. Matthews correlation coefficient (MCC) was used in conjunction with receiver operating characteristic analysis (ROC) to assess if and which parameter was most suitable for short-term mortality prediction. The intra-class correlation coefficient assessed consensus across readers. To validate the results for the best predictor, a second cohort was evaluated (Group B: 354 CT scans).

RESULTS

The portal venous spleno-aortic ratio was best suited to predict 72-hour mortality (AUC = 0.91). A threshold ratio ≤0.53 predicted short-term mortality with a high sensitivity (80.95%) and specificity (96.74%, MCC = 0.79). The post-test probability was 85%, assuming a pre-test probability of 18.6% (72-hour mortality rate). ICCs of HU measurements in the aorta, spleen, and its ratios showed high interrater agreement (ICC: 0.92-0.99). In a control cohort, a threshold ratio ≤0.53 predicted CCU patientś outcome satisfactorily (SENS = 83.93%, SPEC = 97.65%, PPV = 87.00%, NPV = 97.00%).

CONCLUSIONS

The portal venous spleno-aortic ratio serves as a distinctive imaging feature to predict short-term mortality. For CCU patients with a cut-off portal venous spleno-aortic ratio ≤0.53, the risk of dying within three days after CT scan is approximately twenty times higher.

More is More? Total Pancreatectomy for Periampullary Cancer as an Alternative in Patients with High-Risk Pancreatic Anastomosis: A Propensity Score-Matched Analysis

Background

Postpancreatectomy morbidity remains significant even in high-volume centers and frequently results in delay or suspension of indicated adjuvant oncological treatment. This study investigated the short-term and long-term outcome after primary total pancreatectomy (PTP) and pylorus-preserving pancreaticoduodenectomy (PPPD) or Whipple procedure, with a special focus on administration of adjuvant therapy and oncological survival.

Methods

Patients who underwent PTP or PPPD/Whipple for periampullary cancer between January 2008 and December 2017 were retrospectively analyzed. Propensity score-matched analysis was performed to compare perioperative and oncological outcomes. Correspondingly, cases of rescue completion pancreatectomy (RCP) were analyzed.

Results

In total, 41 PTP and 343 PPPD/Whipple procedures were performed for periampullary cancer. After propensity score matching, morbidity (Clavien-Dindo classification (CDC) ≥ IIIa, 31.7% vs. 24.4%; p = 0.62) and mortality rates (7.3% vs. 2.4%, p = 0.36) were similar in PTP and PPPD/Whipple. Frequency of adjuvant treatment administration (76.5% vs. 78.4%; p = 0.87), overall survival (513 vs. 652 days; p = 0.47), and progression-free survival (456 vs. 454 days; p = 0.95) did not significantly differ. In turn, after RCP, morbidity (CDC ≥ IIIa, 85%) and mortality (40%) were high, and overall survival was poor (median 104 days). Indicated adjuvant therapy was not administered in 77%.

Conclusions

In periampullary cancers, PTP may provide surgical and oncological treatment outcomes comparable with pancreatic head resections and might save patients from RCP. Especially in selected cases with high-risk pancreatic anastomosis or preoperatively impaired glucose tolerance, PTP may provide a safe treatment alternative to pancreatic head resection.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10292-8.

Wound complications after primary and repeated midline, transverse and modified Makuuchi incision: A single-center experience in 696 patients

There are 3 main types of incisions in major open, elective abdominal surgery: the midline incision (MI), the transverse incision (TI) and the modified Makuuchi incision (MMI). This study aimed to compare these approaches regarding wound complications and hernias, with a special focus on suture material and previous laparotomies.Patients who underwent elective abdominal surgery between 2015 and 2016 were retrospectively analyzed. Uni- and multivariate analyses were computed using stepwise binary and multifactorial regression models.In total, 696 patients (406 MI, 137 TI and 153 MMI) were included. No relevant differences were observed for patient characteristics (e.g., sex, age, body mass index [BMI], American Society of Anesthesiologists [ASA] score). Fewer wound complications (TI 22.6% vs MI 33.5% vs MMI 32.7%, P = .04) occurred in the TI group. However, regarding the endpoints surgical site infection (SSI), fascial dehiscence and incisional hernia, no risk factor after MI, TI, and MMI could be detected in statistical analysis. There was no difference regarding the occurrence of fascial dehiscence (P = .58) or incisional hernia (P = .97) between MI, TI, and MMI. In cases of relaparotomies, the incidence of fascial dehiscence (P = .2) or incisional hernia (P = .58) did not significantly differ between the MI, TI, or MMI as well as between primary and reincision of each type. On the other hand, the time to first appearance of a hernia after MMI is significantly shorter (P = .03) than after MI or TI, even after previous laparotomy (P = .003).In comparing the 3 most common types of abdominal incisions and ignoring the type of operative procedure performed, TI seems to be the least complicated approach. However, because the incidence of fascial dehiscence and incisional hernia is not relevantly increased, the stability of the abdominal wall is apparently not affected by relaparotomy, even by repeated MIs, TIs, and MMIs. Therefore, the type of laparotomy, especially a relaparotomy, can be chosen based on the surgeon's preference and planned procedure without worrying about increased wound complications.

Disease duration before surgical resection for chronic pancreatitis impacts long-term outcome

Many patients with chronic pancreatitis (CP) undergo a step-up approach with interventional procedures as first-line treatment and resection reserved for later stages. The aim of this study was to identify predictive factors for a significant clinical improvement (SCI) after surgical treatment.All patients operated for CP between September 2012 and June 2017 at our center was retrospectively reviewed. A prospective patient survey was conducted to measure patients postoperative outcome. The primary endpoint SCI was defined as stable health status, positive weight development and complete pain relief without routine pain medication. Additionally, risk factors for relaparotomy were analyzed.A total of 89 patients with a median follow-up of 38 months were included. In most cases, a duodenum-preserving pancreatic head resection (n = 48) or pancreatoduodenectomy (n = 28) was performed. SCI was achieved in 65.3% (n = 47) of the patients after the final medium follow-up of 15.0 months (IQR: 7.0-35.0 months), respectively. Patients with a longer mean delay (7.7 vs 4 years) between diagnosis and surgical resection were less likely to achieve SCI (P = .02; OR .88; 95%CI .80-98). An endocrine insufficiency was a negative prognostic factor for SCI (P = .01; OR .15; 95%CI .04-68). In total, 96.2% of the patients had a complete or major postoperative relief with a mean pain intensity reduction from 8.1 to 1.9 on the visual analogue scale.The results support that surgical resection for CP should be considered at early stages. Resection can effectively reduce postoperative pain intensity and improve long-term success.

Impact of pulmonary embolism on morbidity and mortality in patients undergoing pancreatic surgery

PURPOSE

Postoperative pulmonary embolism (PE) after pancreatic surgery is a potentially life-threatening complication. However, the magnitude of morbidity and mortality of PE is still uncertain. The present study aims to assess the incidence of PE after pancreatic surgery and analyze its impact on the outcome.

METHODS

We conducted a retrospective study including all patients who underwent pancreatic resections between 2005 and 2017. The development of PE was analyzed for a 90-day period following surgery. Risk factors were evaluated using regression models.

RESULTS

The study investigated 947 patients undergoing pancreatic surgery. Overall, 26 (2.7%) patients developed PE. The median body mass index (BMI) of patients with PE was significantly higher (28.1 kg/m² [24.7-31.8] vs. 24.8 kg/m² [22.4-27.8], p < 0.001). Patients with PE had a significantly increased duration of the operation and more often underwent multivisceral resections. The lowest incidence of PE was found after distal or total pancreatectomy (2%). In median, PE occurred on the fifth postoperative day (interquartile range: 3-9). Increased BMI, duration of operation, and postoperative deep venous thrombosis were found to be multivariate risk factors for the development of PE. Importantly, postoperative complications (53.8% vs. 15.1%, p < 0.001) and the 30-day mortality rate were significantly increased in the PE group (19.2% vs. 3.3%, p < 0.001).

CONCLUSIONS

Patients with increased BMI, a history of deep venous thrombosis, and multivisceral resections are a high-risk group for PE after pancreatic surgery. While the absolute incidence and related mortality of PE after pancreatic surgery is low, it is associated with severe sequelae.

Simple Wound Irrigation in the Postoperative Treatment for Surgically Drained Spontaneous Soft Tissue Abscesses: A Prospective, Randomized Controlled Trial

BACKGROUND

Soft tissue abscesses are among the most frequently encountered medical problems treated by different surgeons. Standard therapy remains incision and drainage with sterile saline irrigation during postoperative wound healing period. Aim of this prospective randomized controlled trial was to compare sterile irrigation versus nonsterile irrigation.

STUDY DESIGN

A single center randomized controlled trial was performed to investigate postoperative wound irrigation. The control group used sterile irrigation, and the intervention group used nonsterile irrigation. Primary endpoints were reinfection and reintervention rates, assessed during follow-up controls for up to 2 years. Secondary endpoints were the duration of wound healing, inability to work, pain and quality of life.

RESULTS

Between 04/2016 and 05/2017, 118 patients were randomized into two groups, with 61 allocated to the control- and 57 to the intervention group. Reinfection occurred in a total of 4 cases (6.6%) in the sterile protocol and 4 (7%) in the nonsterile protocol. Quality of life and pain values were comparable during the wound healing period, and patients treated according to the nonsterile irrigation protocol used significantly fewer wound care service teams. Despite equal wound persistence rates, a substantially shorter amount of time off from work was reported in the nonsterile protocol group (p value 0.086).

CONCLUSION

This prospective, randomized trial indicates that a nonsterile irrigation protocol for patients operated on for soft tissue abscesses is not inferior to the standard sterile protocol. Moreover, a nonsterile irrigation protocol leads to a shorter period of inability to work with comparable pain and quality of life scores during the wound healing period.

Prognostic impact of para-aortic lymph node metastases in non-pancreatic periampullary cancer

Background

Resection of the para-aortic lymph node (PALN) group Ln16b1 during pancreatoduodenectomy remains controversial because PALN metastases are associated with a worse prognosis in pancreatic cancer patients. The present study aimed to analyze the impact of PALN metastases on outcome after non-pancreatic periampullary cancer resection.

Methods

One hundred sixty-four patients with non-pancreatic periampullary cancer who underwent curative pancreatoduodenectomy or total pancreatectomy between 2005 and 2016 were retrospectively investigated. The data were supplemented with a systematic literature review on this topic.

Results

In 67 cases, the PALNs were clearly assigned and could be histopathologically analyzed. In 10.4% of cases (7/67), tumor-infiltrated PALNs (PALN+) were found. Metastatic PALN+ stage was associated with increased tumor size (P = 0.03) and a positive nodal stage (P < 0.001). The median overall survival (OS) of patients with metastatic PALN and non-metastatic PALN (PALN–) was 24.8 and 29.5 months, respectively. There was no significant difference in the OS of PALN+ and pN1 PALN patients (P = 0.834). Patients who underwent palliative surgical treatment (n = 20) had a lower median OS of 13.6 (95% confidence interval 2.7–24.5) months. Including the systematic literature review, only 23 cases with PALN+ status and associated OS could be identified; the average survival was 19.8 months.

Conclusion

PALN metastasis reflects advanced tumor growth and lymph node spread; however, it did not limit overall survival in single-center series. The available evidence of the prognostic impact of PALN metastasis is scarce and a recommendation against resection in these cases cannot be given.

Drain Amylase or Lipase for the Detection of POPF-Adding Evidence to an Ongoing Discussion

Objectives: A postoperative pancreatic fistula (POPF) is defined as a threefold increase in the amylase concentration in abdominal drains on or after the third postoperative day (POD). However, additional lipase fluid analysis is widely used despite lacking evidence. In this study, drain amylase and lipase levels were compared regarding their value in detecting POPF. Methods: We conducted a retrospective study including all patients who underwent pancreatic resections at our center between 2005 and 2016. Drain fluid analysis was performed from day 2 to 5. Results: 990 patients were included in the analysis. Overall, 333 (34%) patients developed a POPF. The median amylase and lipase concentrations at POD 3 in cases with POPF were 11.55 µmol/(s·L) (≈13 ×-fold increase) and 39 µmol/(s·L) (≈39 ×-fold increase), respectively. Seven patients with subsequent POPF (2%) were missed with amylase analysis on POD 3, but detected using 3-fold lipase analysis. The false-positive rate of lipase was 51/424 = 12%. A cutoff lipase value at POD 3 of > 4.88 yielded a specificity of 94% and a sensitivity of 89% for development of a POPF. Increased body mass index turned out as risk factor for the development of POPF in a multivariable model. Conclusions: Threefold-elevated lipase concentration may be used as an indicator of a POPF. However, the additional detection of POPF using simultaneous lipase analysis is marginal. Therefore, assessment of lipase concentration does not provide added clinical value and only results in extra costs.

MiR-132 controls pancreatic beta cell proliferation and survival through Pten/Akt/Foxo3 signaling

Objective

MicroRNAs (miRNAs) play an integral role in maintaining beta cell function and identity. Deciphering their targets and precise role, however, remains challenging. In this study, we aimed to identify miRNAs and their downstream targets involved in the regeneration of islet beta cells following partial pancreatectomy in mice.

Methods

RNA from laser capture microdissected (LCM) islets of partially pancreatectomized and sham-operated mice were profiled with microarrays to identify putative miRNAs implicated in beta cell regeneration. Altered expression of the selected miRNAs, including miR-132, was verified by RT-PCR. Potential targets of miR-132 were selected through bioinformatic data mining. Predicted miR-132 targets were validated for their changed RNA, protein expression levels, and signaling upon miR-132 knockdown and/or overexpression in mouse MIN6 and human EndoC-βH1 insulinoma cells. The ability of miR-132 to foster beta cell proliferation in vivo was further assessed in pancreatectomized miR-132^−/− and control mice.

Results

Partial pancreatectomy significantly increased the number of BrdU⁺/insulin⁺ islet cells. Microarray profiling revealed that 14 miRNAs, including miR-132 and -141, were significantly upregulated in the LCM islets of the partially pancreatectomized mice compared to the LCM islets of the control mice. In the same comparison, miR-760 was the only downregulated miRNA. The changed expression of these miRNAs in the islets of the partially pancreatectomized mice was confirmed by RT-PCR only in the case of miR-132 and -141. Based on previous knowledge of its function, we focused our attention on miR-132. Downregulation of miR-132 reduced the proliferation of MIN6 cells while enhancing the levels of pro-apoptotic cleaved caspase-9. The opposite was observed in miR-132 overexpressing MIN6 cells. Microarray profiling, RT-PCR, and immunoblotting of the latter cells demonstrated their downregulated expression of Pten with concomitant increased levels of pro-proliferative factors phospho-Akt and phospho-Creb and inactivation of pro-apoptotic Foxo3a via its phosphorylation. Downregulation of Pten was further confirmed in the LCM islets of pancreatectomized mice compared to the sham-operated mice. Moreover, overexpression of miR-132 correlated with increased proliferation of EndoC-βH1 cells. The regeneration of beta cells following partial pancreatectomy was lower in the miR-132/212^−/− mice than the control littermates.

Conclusions

This study provides compelling evidence about the critical role of miR-132 for the regeneration of mouse islet beta cells through the downregulation of its target Pten. Hence, the miR-132/Pten/Akt/Foxo3 signaling pathway may represent a suitable target to enhance beta cell mass.

•

miR-132 is induced in mouse islets upon partial pancreatectomy.

•

miR-132 promotes regeneration of β-cells in vivo following partial pancreatectomy.

•

miR-132 fosters in vitro proliferation/survival through Pten/Akt/Foxo3 signaling.

•

Downstream targets of miR-132 were identified in pancreatic β-cells.

•

miR-132^−/− mice have impaired β-cell proliferation.

[Outpatient Drain Management in Patients with Clinically Relevant Postoperative Pancreatic Fistula (CR-POPF) - Current Status in Germany]

INTRODUCTION

Postoperative pancreatic fistula (POPF) is a common complication after pancreatic surgery and is associated with extended hospitalisation, increased medical costs, and reduced quality of life. The aim of the present study was to assess the treatment of POPF in Germany, with a special focus on outpatient drain management in patients with clinically relevant POPF (CR-POPF).

METHODS

A questionnaire evaluating postoperative management once a CR-POPF is diagnosed - especially focusing on ambulatory drain management - was developed and sent to 211 German hospitals performing > 12 pancreatic operations per year. Statistical analysis was carried out using SPSS 21.

RESULTS

The final response rate was 62% (n = 131). Outpatient drainage management is performed by most of the responding hospitals (n = 100, 76.3%). However, 30% of hospitals (n = 40) perform outpatient treatment only in 5% of their cases with clinically relevant POPF. There was no correlation between case load of the pancreatic centres and frequency of outpatient drain management. In general, discharge criteria for patients with drained POPF (n = 98, 74.8%), the drain management itself (n = 95, 72.5%) and criteria for drain removal (n = 74, 56.5%) are not standardised but made individually. In centres with standardised drain management criteria for drain removal, these criteria were drain volume < 20 ml (29.8%), no fluid collection (25.2%), no elevation of drain amylase/lipase (25.2%) and no specific symptoms (22.1%).

CONCLUSION

This is the first survey in Germany evaluating outpatient drain management in patients with CR-POPF. Although the data in the literature are rare, the majority of German pancreatic surgeons perform outpatient drain management. However, discharge criteria, outpatient care and drain removal are standardised in only the minority of centres. Therefore, we recommend the evaluation of discharge criteria and a management algorithm for patients with drained CR-POPF to improve the perioperative course.

Para-aortic lymph node metastases in pancreatic cancer should not be considered a watershed for curative resection

No international consensus regarding the resection of the para-aortic lymph node (PALN) station Ln16b1 during pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) has been reached. The present retrospectively investigated 264 patients with PDAC who underwent curative pancreatoduodenectomy or total pancreatectomy between 2005–2015. In 95 cases, the PALN were separately labelled and histopathologically analysed. Metastatic PALN (PALN+) were found in 14.7% (14/95). PALN+ stage was associated with increased regional lymph node metastasis. The median overall survival (OS) of patients with metastatic PALN and with non-metastatic PALN (PALN−) was 14.1 and 20.2 months, respectively. Five of the PALN+ patients (36%) survived >19 months. The OS of PALN+ and those staged pN1 PALN− was not significantly different (P = 0.743). Patients who underwent surgical exploration or palliative surgery (n = 194) had a lower median survival of 8.8 (95% confidence interval: 7.3–10.1) months. PALN status could not be reliably predicted by preoperative computed tomography. We concluded that the survival data of PALN+ cases is comparable with advanced pN+ stages; one-third of the patients may expect longer survival after radical resection. Therefore, routine refusal of curative resection in the case of PALN metastasis is not indicated.

Outpatient Drainmanagement of patients with clinically relevant Postoperative Pancreatic Fistula (POPF)

PURPOSE

Postoperative pancreatic fistula (POPF) is a common complication after pancreatic surgery associated with extended hospitalization, increased medical costs, and reduced quality of life. The aim of the present study was to analyze the feasibility of ambulatory drainage and develop an ambulatory management algorithm.

METHODS

Patients with POPF grade B or C (according to the ISGPF classification) between Jan. 2005 and Dec. 2014 that required persistent drainage were identified from a prospectively collected database. Postoperative events and clinical outcomes were retrospectively analyzed.

RESULTS

A total of 132 out of 887 patients (14.8%) developed a POPF (grade B or C), and 45 (34.1%) were discharged from the hospital with percutaneous drainage. For patients with grade B fistulas, the mean hospital stay was significantly shorter compared to patients with grade C fistulas (mean 27.7 vs. 40 days; p = 0.0285). About 40% of patients with ambulatory drainage developed a complication, but only 28.9% required readmission. Of those, 52.9% did not require specific treatment and 26.3% were treated with a new drain placement. None of the patients developed major complications, and there was no difference in the frequency of complications between the two groups (p = 0.872). The duration of drain persistence was significantly shorter for patients with grade B fistulas than for those with grade C fistulas (52.2 vs. 85.9 days; p = 0.0007).

CONCLUSIONS

Ambulatory drainage management is feasible in selected patients. No severe complications occurred during ambulatory drainage management. A management algorithm is recommended as this could possibly reduce medical costs and improve quality of life.

Impact of Portal Vein Involvement from Pancreatic Cancer on Metastatic Pattern After Surgical Resection

BACKGROUND

The present study aims to evaluate the long-term outcome and metastatic pattern of patients who underwent resection of a pancreatic ductal adenocarcinoma (PDAC) with portal or superior mesenteric vein (PV/SMV) resection.

METHODS

Patients who underwent a partial pancreatoduodenectomy or total pancreatectomy for PDAC between 2005 and 2015 were retrospectively analyzed. Three subgroups were generated, depending on PV/SMV resection (P⁺) and pathohistological PV/SMV tumor infiltration (I⁺): P⁺I⁺, P⁺I^-, and P^-I^-. Statistical analysis was performed using the R software package.

RESULTS

The study cohort included 179 patients, 113 of whom underwent simultaneous PV/SMV resection. Thirty-six patients (31.9 %) had pathohistological tumor infiltration of the PV/SMV (P⁺I⁺), and were matched with 66 cases without PV/SMV infiltration (P^-I^-). The study revealed differences in overall median survival (11.9 [P⁺I⁺] vs. 16.1 [P⁺I^-] vs. 20.1 [P^-I^-] months; p = 0.01). Multivariate survival analysis identified true invasion of the PV/SMV as the only significant, negative prognostic factor (p = 0.01). Whereas the incidence of local recurrence was comparable (p = 0.96), the proportion of patients with distant metastasis showed significant differences (75 % [P⁺I⁺] vs. 45.8 % [P⁺I^-] vs. 54.7 % [P^-I^-], p = 0.01). Furthermore, the median time to progression was significantly shorter if the PV/SMV was involved (7.4 months [P⁺I⁺] vs. 10.9 months [P⁺I^-] vs. 11.6 months [P^-I^-]). Initial liver metastases occurred in 33 % of the patients.

CONCLUSIONS

True invasion of the PV/SMV is an independent risk factor for overall survival, and is associated with a higher incidence of distant metastasis and shorter progressive-free survival. Radical vascular resection cannot compensate for aggressive tumor biology.

The genetic contribution of the NO system at the glutamatergic post-synapse to schizophrenia: further evidence and meta-analysis

NO is a pleiotropic signaling molecule and has an important role in cognition and emotion. In the brain, NO is produced by neuronal nitric oxide synthase (NOS-I, encoded by NOS1) coupled to the NMDA receptor via PDZ interactions; this protein-protein interaction is disrupted upon binding of NOS1 adapter protein (encoded by NOS1AP) to NOS-I. As both NOS1 and NOS1AP were associated with schizophrenia, we here investigated these genes in greater detail by genotyping new samples and conducting a meta-analysis of our own and published data. In doing so, we confirmed association of both genes with schizophrenia and found evidence for their interaction in increasing risk towards disease. Our strongest finding was the NOS1 promoter SNP rs41279104, yielding an odds ratio of 1.29 in the meta-analysis. As findings from heterologous cell systems have suggested that the risk allele decreases gene expression, we studied the effect of the variant on NOS1 expression in human post-mortem brain samples and found that the risk allele significantly decreases expression of NOS1 in the prefrontal cortex. Bioinformatic analyses suggest that this might be due the replacement of six transcription factor binding sites by two new binding sites as a consequence of proxy SNPs. Taken together, our data argue that genetic variance in NOS1 resulting in lower prefrontal brain expression of this gene contributes to schizophrenia liability, and that NOS1 interacts with NOS1AP in doing so. The NOS1-NOS1AP PDZ interface may thus well constitute a novel target for small molecules in at least some forms of schizophrenia.

IgA antibody production by intrarectal immunization of mice using recombinant major capsid protein of hamster polyomavirus

Viral proteins are highly antigenic and known as potent stimulators of adaptive immune responses. This mechanism is often used for biotechnological applications in monoclonal antibody production resulting in high-affinity IgG antibodies in most cases. The aim of this study was to increase antigen-specific IgA antibody levels in mice in order to generate monoclonal IgA antibodies by hybridoma technology. For this purpose, hamster polyomavirus (HaPyV) major capsid protein VP1 was used to immunize mice by different routes in order to induce VP1-specific IgA titers. Recombinant HaPyV-VP1 was generated in Escherichia coli and administered intraperitoneally, orally, and intrarectally. VP1-specific antibodies were determined by ELISA in sera and organ culture supernatants. We found a significant increase of HaPyV-VP1-specific IgAs in spleen organ cultures after rectal immunization of mice but not in cultures of mesenteric lymph nodes, colon, or Peyer's patches. In contrast, oral and intraperitoneal immunization did not provide an appropriate specific IgA induction at all. These results show that specific IgA antibodies can be induced by intrarectal immunization in the spleen. The generation of monoclonal IgA antibodies with well-defined properties is a useful tool for the investigation of mucosal immune responses or autoimmune diseases and extends the spectrum of antibodies with specific effector functions.

Inner composition alignment for inferring directed networks from short time series

Identifying causal links (couplings) is a fundamental problem that facilitates the understanding of emerging structures in complex networks. We propose and analyze inner composition alignment-a novel, permutation-based asymmetric association measure to detect regulatory links from very short time series, currently applied to gene expression. The measure can be used to infer the direction of couplings, detect indirect (superfluous) links, and account for autoregulation. Applications to the gene regulatory network of E. coli are presented.

Identifying quality improvement intervention evaluations: is consensus achievable?

BACKGROUND

The diversity of quality improvement interventions (QIIs) has impeded the use of evidence review to advance quality improvement activities. An agreed-upon framework for identifying QII articles would facilitate evidence review and consensus around best practices.

AIM

To adapt and test evidence review methods for identifying empirical QII evaluations that would be suitable for assessing QII effectiveness, impact or success.

DESIGN

Literature search with measurement of multilevel inter-rater agreement and review of disagreement.

METHODS

Ten journals (2005-2007) were searched electronically and the output was screened based on title and abstract. Three pairs of reviewers then independently rated 22 articles, randomly selected from the screened list. Kappa statistics and percentage agreement were assessed. 12 stakeholders in quality improvement, including QII experts and journal editors, rated and discussed publications about which reviewers disagreed.

RESULTS

The level of agreement among reviewers for identifying empirical evaluations of QII development, implementation or results was 73% (with a paradoxically low kappa of 0.041). Discussion by raters and stakeholders regarding how to improve agreement focused on three controversial article selection issues: no data on patient health, provider behaviour or process of care outcomes; no evidence for adaptation of an intervention to a local context; and a design using only observational methods, as correlational analyses, with no comparison group.

CONCLUSION

The level of reviewer agreement was only moderate. Reliable identification of relevant articles is an initial step in assessing published evidence. Advancement in quality improvement will depend on the theory- and consensus-based development and testing of a generalizable framework for identifying QII evaluations.

Finding order in heterogeneity: types of quality-improvement intervention publications

BACKGROUND

Stakeholders in quality improvement agree on the need for augmenting and synthesising the scientific literature supporting it. The diversity of perspectives, approaches, and contexts critical to advancing quality improvement science, however, creates challenges. The paper explores the heterogeneity in clinical quality improvement intervention (QII) publications.

METHODS

A preliminary classification framework was developed for QII articles, aiming for categories homogeneous enough to support coherent scientific discussion on QII reporting standards and facilitate systematic review. QII experts were asked to identify articles important to QII science. The framework was tested and revised by applying it to the article set. The final framework screened articles into (1) empirical literature on development and testing of QIIs; (2) QII stories, theories, and frameworks; (3) QII literature syntheses and meta-analyses; or (4) development and testing of QII-related tools. To achieve homogeneity, category (1) required division into (1a) development of QIIs; 1(b) history, documentation, or description of QIIs; or (1c) success, effectiveness or impact of QIIs.

RESULTS

By discussing unique issues and established standards relevant to each category, QII stakeholders can advance QII practice and science, including the scope and conduct of systematic literature reviews.

Community structure of arbuscular mycorrhizal fungi associated to Veronica rechingeri at the Anguran zinc and lead mining region

Root colonization and diversity of arbuscular mycorrhizal fungi (AMF) were analyzed in Veronica rechingeri growing in heavy metal (HM) and non-polluted soils of the Anguran Zn and Pb mining region (Iran). Three species could be separated morphologically, while phylogenetic analyses after PCR amplification of the ITS region followed by RFLP and sequencing revealed seven different AMF sequence types all within the genus Glomus. Rarefaction analysis confirmed exhaustive molecular characterization of the AMF diversity present within root samples. Increasing heavy metal contamination between the sites studied was accompanied by a decrease in AMF spore numbers, mycorrhizal colonization parameters and the number of AMF sequence types colonizing the roots. Some AMF sequence types were only found at sites with the highest and lowest soil HM contents, respectively.

Risk factors for chronic fatigue syndrome/myalgic encephalomyelitis: a systematic scoping review of multiple predictor studies

BACKGROUND

The aetiology of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is still unknown. The identification of risk factors for CFS/ME is of great importance to practitioners.

METHOD

A systematic scoping review was conducted to locate studies that analysed risk factors for CFS/ME using multiple predictors. We searched for published and unpublished literature in 11 electronic databases, reference lists of retrieved articles and guideline stakeholder submissions in conjunction with the development of a forthcoming national UK guideline. Risk factors and findings were extracted in a concise tabular overview and studies synthesized narratively.

RESULTS

Eleven studies were identified that met inclusion criteria: two case-control studies, four cohort studies, three studies combining a cohort with a case-control study design, one case-control and twin study and one cross-sectional survey. The studies looked at a variety of demographic, medical, psychological, social and environmental factors to predict the development of CFS/ME. The existing body of evidence is characterized by factors that were analysed in several studies but without replication of a significant association in more than two studies, and by studies demonstrating significant associations of specific factors that were not assessed in other studies. None of the identified factors appear suitable for the timely identification of patients at risk of developing CFS/ME within clinical practice.

CONCLUSIONS

Various potential risk factors for the development of CFS/ME have been assessed but definitive evidence that appears meaningful for clinicians is lacking.

Diagnostic tests and algorithms used in the investigation of haematuria: systematic reviews and economic evaluation

OBJECTIVES

To determine the most effective diagnostic strategy for the investigation of microscopic and macroscopic haematuria in adults.

DATA SOURCES

Electronic databases from inception to October 2003, updated in August 2004.

REVIEW METHODS

A systematic review was undertaken according to published guidelines. Decision analytic modelling was undertaken, based on the findings of the review, expert opinion and additional information from the literature, to assess the relative cost-effectiveness of plausible alternative tests that are part of diagnostic algorithms for haematuria.

RESULTS

A total of 118 studies met the inclusion criteria. No studies that evaluated the effectiveness of diagnostic algorithms for haematuria or the effectiveness of screening for haematuria or investigating its underlying cause were identified. Eighteen out of 19 identified studies evaluated dipstick tests and data from these suggested that these are moderately useful in establishing the presence of, but cannot be used to rule out, haematuria. Six studies using haematuria as a test for the presence of a disease indicated that the detection of microhaematuria cannot alone be considered a useful test either to rule in or rule out the presence of a significant underlying pathology (urinary calculi or bladder cancer). Forty-eight of 80 studies addressed methods to localise the source of bleeding (renal or lower urinary tract). The methods and thresholds described in these studies varied greatly, precluding any estimate of a 'best performance' threshold that could be applied across patient groups. However, studies of red blood cell morphology that used a cut-off value of 80% dysmorphic cells for glomerular disease reported consistently high specificities (potentially useful in ruling in a renal cause for haematuria). The reported sensitivities were generally low. Twenty-eight studies included data on the accuracy of laboratory tests (tumour markers, cytology) for the diagnosis of bladder cancer. The majority of tumour marker studies evaluated nuclear matrix protein 22 or bladder tumour antigen. The sensitivity and specificity ranges suggested that neither of these would be useful either for diagnosing bladder cancer or for ruling out patients for further investigation (cystoscopy). However, the evidence remains sparse and the diagnostic accuracy estimates varied widely between studies. Fifteen studies evaluating urine cytology as a test for urinary tract malignancies were heterogeneous and poorly reported. The calculated specificity values were generally high, suggesting some possible utility in confirming malignancy. However, the evidence suggests that urine cytology has no application in ruling out malignancy or excluding patients from further investigation. Fifteen studies evaluated imaging techniques [computed tomography (CT), intravenous urography (IVU) or ultrasound scanning (US)] to detect the underlying cause of haematuria. The target condition and the reference standard varied greatly between these studies. The diagnostic accuracy data for several individual studies appeared promising but meaningful comparison of the available imaging technologies was impossible. Eight studies met the inclusion criteria but addressed different parts of the diagnostic chain (e.g. screening programmes, laboratory investigations, full urological work-up). No single study addressed the complete diagnostic process. The review also highlighted a number of methodological limitations of these studies, including their lack of generalisability to the UK context. Separate decision analytic models were therefore developed to progress estimation of the optimal strategy for the diagnostic management of haematuria. The economic model for the detection of microhaematuria found that immediate microscopy following a positive dipstick test would improve diagnostic efficiency as it eliminates the high number of false positives produced by dipstick testing. Strategies that use routine microscopy may be associated with high numbers of false results, but evidence was lacking regarding the accuracy of routine microscopy and estimates were adopted for the model. The model for imaging the upper urinary tract showed that US detects more tumours than IVU at one-third of the cost, and is also associated with fewer false results. For any cause of haematuria, CT was shown to have a mean incremental cost-effectiveness ratio of pounds sterling 9939 in comparison with the next best option, US. When US is followed up with CT for negative results with persistent haematuria, it dominates the initial use of CT alone, with a saving of pounds sterling 235,000 for the evaluation of 1000 patients. The model for investigation of the lower urinary tract showed that for low-risk patients the use of immediate cystoscopy could be avoided if cystoscopy were used for follow-up patients with a negative initial test using tumour markers and/or cytology, resulting in a saving of pounds sterling 483,000 for the evaluation of 1000 patients. The clinical and economic impact on delayed detection of both upper and lower urinary tract tumours through the use of follow-up testing should be evaluated in future studies.

CONCLUSIONS

There are insufficient data currently available to derive an evidence-based algorithm of the diagnostic pathway for haematuria. A hypothetical algorithm based on the opinion and practice of clinical experts in the review team, other published algorithms and the results of economic modelling is presented in this report. This algorithm is presented, for comparative purposes, alongside current US and UK guidelines. The ideas contained in these algorithms and the specific questions outlined should form the basis of future research. Quality assessment of the diagnostic accuracy studies included in this review highlighted several areas of deficiency.

Hepatocyte proliferation and apoptosis in rat liver after liver injury

BACKGROUND/AIMS

In this paper the early phase of proliferate response and apoptosis of hepatocytes after partial liver resection, during reperfusion after ischemia and during sepsis is demonstrated.

METHODOLOGY

Experiments were conducted in a rat model with regeneration times of 0.5-24 hours after injury. Proliferation was analyzed by Ki-67 immunohistochemistry and confirmed by double staining with CK18 in FACS. Apoptosis was analyzed by TUNEL technique.

RESULTS

Periportal hepatocytes enter the cell cycle already 0.5-2 hours after injury in all three models. This early proliferative response is predominant periportally localized. During reperfusion and during sepsis there was a strict pericentral apoptosis of hepatocytes found.

CONCLUSIONS

An early periportal proliferation of hepatocytes is a common reaction of the liver to injury. This proliferation takes place much earlier then the main proliferative response 24-72 h after partial resection. This predominant periportal proliferation together with the pericentral apoptosis fit to the concept of the "streaming liver" in liver regeneration.

Effect of liver regeneration after partial hepatectomy and ischemia-reperfusion on expression of growth factor receptors

AIM: To investigate the effects of experimental partial hepatectomy and normothermic ischemia-reperfusion damage on the time course of the expression of four different growth factor receptors in liver regeneration. This is relevant due to the potential therapeutic use of growth factors in stimulating liver regeneration.

METHODS: For partial hepatectomy (PH) 80% of the liver mass was resected in Sprague Dawley rats. Ischemia and reperfusion (I/R) were induced by occlusion of the portal vein and the hepatic artery for 15 min. The epidermal growth factor receptor, hepatic growth factor receptor, fibroblast growth factor receptor and tumour necrosis factor receptor-1 were analysed by immunohistochemistry up to 72 h after injury. Quantitative RT-PCR was performed at the time point of minimal receptor expression (24 h).

RESULTS: In immunohistochemistry, EGFR, HGFR, FGFR and TNFR1 showed biphasic kinetics after partial hepatectomy with a peak up to 12 h, a nadir after 24 h and another weak increase up to 72 h. During liver regeneration, after ischemia and reperfusion, the receptor expression was lower; the nadir at 24 h after reperfusion was the same. To evaluate whether this nadir was caused by a lack of mRNA transcription, or due to a posttranslational regulation, RT-PCR was performed at 24 h and compared to resting liver. In every probe there was specific mRNA for the receptors. EGFR, FGFR and TNFR1 mRNA expression was equal or lower than in resting liver, HGFR expression after I/R was stronger than in the control.

CONCLUSION: At least partially due to a post-transcrip-tional process, there is a nadir in the expression of the analysed receptors 24 h after liver injury. Therefore, a therapeutic use of growth factors to stimulate liver regeneration 24 h after the damage might be not successful.

Zonation of hepatic bile salt transporters

Pericentral and periportal hepatocytes differ in their capacity to eliminate and velocity of eliminating bile acids and other organic anions. We wonder whether differences in the distribution of anion transporters (ntcp [M77479], besp [NM_031760], mrp2 [NM_012833], oatp1 [NM_017111], oatp2 [NM_131906]) cause the differences in bile acid excretion. Therefore, we analyzed the distribution of these anion transporters in periportal and pericentral cells by immunohistology, their mRNA by quantitative PCR, and regulating nuclear factors (NF-kappaB, HNF1, HNF3, HNF4, FXR, PXR) by gel shift assay. We did not find any differences in nuclear factors or regarding the proteins that could explain the zonal differences in anion transport.

Kupffer cells infiltrate liver tissue early after ischemia-reperfusion and partial hepatectomy

Kupffer cells, ED2+macrophages of the liver, play an important role in liver damage and regeneration. It is proposed that Kupffer cells are stationary and regenerate after acute liver trauma by local proliferation. We analyzed their kinetics in three surgically relevant murine models of acute liver injury: partial liver resection, ischemia with reperfusion and sepsis. We found an early increase in ED2+cells after 0.5 h and a maximum after 12 h. These results suggest an infiltration of the cells early after the injury and a later local proliferation. These ED2+macrophages are localized predominantly periportally; nearly no macrophages are found pericentrally, except in the sepsis model. Therefore, a shifting of macrophages from portal to central seems to be unlikely, suggesting a hepatic zonation of homing factors.

Criticizing and reassuring oneself: An exploration of forms, styles and reasons in female students

OBJECTIVES

Self-critical people, compared with those who self-reassure, are at increased risk of psychopathology. However, there has been little work on the different forms and functions of these self-experiences. This study developed two self-report scales to measure forms and functions of self-criticism and self-reassurance and explore their relationship to depression.

METHODS

A self-report scale measuring forms of self-criticism and self-reassuring, and a scale measuring possible functions of self-criticism, together with a measure of depression and another self-criticism scale (LOSC), were given to 246 female students.

RESULTS

Self-criticizing vs. self-reassuring separated into two components. Forms of self-criticizing separated into two components related to: being self-critical, dwelling on mistakes and sense of inadequacy; and a second component of wanting to hurt the self and feeling self-disgust/hate. The reasons/functions for self-criticism separated into two components. One was related to desires to try to self-improve (called self-improving/correction), and the other to take revenge on, harm or hurt the self for failures (called self-harming/persecuting). Mediation analysis suggested that wanting to harm the self may be particularly pathogenic and is positively mediated by the effects of hating the self and negatively mediated by being able to self-reassure and focus on one's positives.

CONCLUSIONS

Self-criticism is not a single process but has different forms, functions, and underpinning emotions. This indicates a need for more detailed research into the variations of self-criticism and the mechanisms for developing self-reassurance.

Sequence and analysis of chromosome 5 of the plant Arabidopsis thaliana

The genome of the model plant Arabidopsis thaliana has been sequenced by an international collaboration, The Arabidopsis Genome Initiative. Here we report the complete sequence of chromosome 5. This chromosome is 26 megabases long; it is the second largest Arabidopsis chromosome and represents 21% of the sequenced regions of the genome. The sequence of chromosomes 2 and 4 have been reported previously and that of chromosomes 1 and 3, together with an analysis of the complete genome sequence, are reported in this issue. Analysis of the sequence of chromosome 5 yields further insights into centromere structure and the sequence determinants of heterochromatin condensation. The 5,874 genes encoded on chromosome 5 reveal several new functions in plants, and the patterns of gene organization provide insights into the mechanisms and extent of genome evolution in plants.

Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana

The higher plant Arabidopsis thaliana (Arabidopsis) is an important model for identifying plant genes and determining their function. To assist biological investigations and to define chromosome structure, a coordinated effort to sequence the Arabidopsis genome was initiated in late 1996. Here we report one of the first milestones of this project, the sequence of chromosome 4. Analysis of 17.38 megabases of unique sequence, representing about 17% of the genome, reveals 3,744 protein coding genes, 81 transfer RNAs and numerous repeat elements. Heterochromatic regions surrounding the putative centromere, which has not yet been completely sequenced, are characterized by an increased frequency of a variety of repeats, new repeats, reduced recombination, lowered gene density and lowered gene expression. Roughly 60% of the predicted protein-coding genes have been functionally characterized on the basis of their homology to known genes. Many genes encode predicted proteins that are homologous to human and Caenorhabditis elegans proteins.

[Perioperative circulatory side effects of topical 5% phenylephrine for mydriasis]

PURPOSE

To study the systemic effects of topically applied 5% phenylephrine. To investigate intraoperative injection of epinephrine in the anterior chamber as an alternative.

METHOD

75 patients undergoing cataract surgery were randomized into three groups. In group 1, the pupil was dilated using topically 5% phenylephrine and 1% cyclopentolate, the patients blocked the lacrimal drainage system themselves by digital compression. Group 2 received the same drops, digital compression was performed by one of the investigators. In Group 3, no preoperative phenylephrine was used--instead, epinephrine 1:25,000 was injected in the anterior chamber at the beginning of surgery. Retrobulbar anesthesia was performed in a short narcosis with ketamine and propofol.

RESULTS

Mean preoperative blood pressure values were higher than the day before. They fell during narcosis, to increase significantly after the injection of the local anesthetics. At the beginning of surgery they were back to prenarcotic values. Intraoperative blood pressure remained stable. Preoperative day values were found two hours postop. There was no significant difference in the circulatory behavior between the three groups. For mydriasis, intraoperative intracameral epinephrine was not as effective as preoperative phenylephrine.

CONCLUSION

In normotonic or medically treated arterial hypertensive patients, preoperative mydriasis using 5% phenylephrine is safe--proceeding the way described above. Compression of the lacrimal drainage system can be performed by the patients effectively. Intraoperative intracameral epinephrine does not replace preoperative phenylephrine.