Presence of SARS-CoV-2 in abdominal tissues and biologic fluids during abdominal surgery: a systematic review

BACKGROUND

Viral transmission to healthcare providers during surgical procedures was a major concern at the outset of the COVID-19 pandemic. The presence of the severe acute respiratory disease syndrome coronavirus (SARS-CoV-2), the virus responsible for COVID-19, in the abdominal cavity as well as in other abdominal tissues which surgeons are exposed has been investigated in several studies. The aim of the present systematic review was to analyze if the virus can be identify in the abdominal cavity.

METHODS

We performed a systematic review to identify relevant studies regarding the presence of SARS-CoV-2 in abdominal tissues or fluids. Number of patients included as well as patient's characteristics, type of procedures, samples and number of positive samples were analyzed.

RESULTS

A total of 36 studies were included (18 case series and 18 case reports). There were 357 samples for detection of SARS-CoV-2, obtained from 295 individuals. A total of 21 samples tested positive for SARS-CoV-2 (5.9%). Positive samples were more frequently encountered in patients with severe COVID-19 (37.5% vs 3.8%, p < 0.001). No health-care provider related infections were reported.

CONCLUSION

Although a rare occurrence, SARS-CoV-2 can be found in the abdominal tissues and fluids. It seems that the presence of the virus in the abdominal tissues or fluids is more likely in patients with severe disease. Protective measures should be employed in the operating room to protect the staff when operating patients with COVID-19.

A nationwide analysis of median arcuate ligament release between 2010 and 2020: a NSQIP Study

BACKGROUND

Median arcuate ligament syndrome is a rare disease with overlapping symptoms of broad foregut pathology. Appropriately selected patients can benefit from a laparoscopic or open median arcuate ligament release. Institutional series have reported the outcomes of open and laparoscopic techniques but there are no nationwide analysis comparing both techniques and overall trends in treatment.

METHODS

Cross-sectional study using the American College of Surgeons-National Surgical Quality Improvement Project from 2010 to 2020. Celiac artery compression syndrome cases were identified by International Classification of Diseases (ICD) codes and categorized as open or laparoscopic. Trends in the use of each technique and 30-day complications were compared between the groups.

RESULTS

A total of 578 open cases (76%) and 185 laparoscopic cases (24%) were identified. There was an increase adoption of the laparoscopic approach, with 22% of the cases employing this technique at the end of the study period, compared to 7% at the beginning of the study period. The open group had a higher prevalence of hypertension (26% vs 18%, p = 0.04) and bleeding disorders (5% vs 2%, p 0.03). Laparoscopic approach had a shorter length of stay (2.3 days vs 5.2 days, p < 0.0001), lower major complication rates (0.5% vs 4.0%, p = 0.02) and lower reoperation rates (0% vs 2.6%, p = 0.03). Overall mortality was 0.1%.

CONCLUSION

Overall numbers of surgical intervention for treatment of median arcuate ligament increased during this timeframe, as well as increased utilization of the laparoscopic approach. It appears to be an overall safe procedure, offering lower rates of complications and shorter length of stay.

The effect of bariatric surgery on circulating levels of lipoprotein(a): a systematic review and meta-analysis

Background

Obesity, and especially severe obesity, are strongly related to higher risk of atherosclerotic cardiovascular disease (ASCVD) morbidity and mortality. Bariatric surgery is an effective weight loss therapy for people with severe obesity and weight-related co-morbid conditions. Elevated plasma level of lipoprotein(a) [Lp(a)] is causally associated with ASCVD.

Purpose

The aim of the present meta-analysis was to analyze whether bariatric surgery could influence Lp(a) concentrations.

Methods

A systematic literature search in PubMed, Scopus, Embase, and Web of Science was performed from inception to May 1st, 2021. A random-effects model and the generic inverse variance weighting method were used to compensate for the heterogeneity of studies in terms of study design, treatment duration, and the characteristics of the studied populations. A random-effect meta-regression model was used to explore the association with an estimated effect size. Evaluation of funnel plot, Begg's rank correlation and Egger's weighted regression tests were used to assess the presence of publication bias in the meta-analysis.

Results

Meta-analysis of 13 studies including 1,551 patients showed a significant decrease of circulating Lp(a) after bariatric surgery (SMD: −0.438, 95% CI: −0.702, −0.174, p&lt;0.001, I2: 94.05%). The results of meta-regression did not indicate any significant association between the changes in Lp(a) and duration of follow up from surgery, reduction in body mass index, or baseline Lp(a) concentration. The reduction in circulating Lp(a) was robust in the leave-one-out sensitivity analysis.

Conclusions

Based on the results of the Mata-analysis we showed that bariatric surgery significantly decreases circulating Lp(a) concentrations.

Funding Acknowledgement

Type of funding sources: None.

Single-center ventral hernia repair with porcine dermis collagen implant

INTRODUCTION

This study aims to evaluate the outcomes and utilization of porcine acellular dermal collagen implant (PADCI) during VHR at a large tertiary referral center.

METHODS

Records of 5485 patients who underwent VIHR from June 1995 to August 2014 were retrospectively reviewed to identify patients >18 years of age who had VIHR with PADCI reinforcement. Use of multiple mesh reinforcement products, inguinal hernias, and hiatal hernias were exclusion criteria. The primary outcome was hernia recurrence, and secondary outcomes were early complications and surgical site occurrences (SSOs). Uni- and multivariate analyses assessed risk factors for recurrence after PADCI reinforced VIHR.

RESULTS

There were 361 patients identified (54.5% female, mean age of 56.7 ± 12.5 years, and mean body mass index (BMI) of 33.0 ± 9.9 kg/m²). Hypertension (49.5%), diabetes (24.3%), and coronary artery disease (14.4%) were the most common comorbidities, as was active smoking (20.7%). Most were classified as American Association of Anesthesiologists (ASA) Class 3 (61.7%). Hernias were distributed across all grades of the ventral hernia working group (VHWG) grading system: grade I 93 (25.7%), grade II 51 (14.1%), grade III 113 (31.3%), and grade IV 6 (1.6%). Most VIHR were performed from an open approach (96.1%), and were frequently combined with concomitant surgical procedures (47.9%). Early postoperative complications (first 30 days) were reported in 39.0%, with 71 being SSO. Of the 19.7% of patients with SSO, there were 31 who required procedural intervention. After a mean follow-up of 71.5 ± 20.5 months, hernia recurrence was documented in 34.9% of patients. Age and male gender were predictors of recurrence on multivariate analysis.

CONCLUSION

To the best of our knowledge, this is the largest retrospective single institutional study evaluating PADCI to date. Hernias repaired with PADCI were frequently in patients undergoing concomitant operations. Reinforcement with PADCI may be considered a temporary closure, with a relatively high recurrence rate, especially among patients who are older, male, and undergo multiple explorations in a short perioperative period.

Safety and efficacy of bariatric surgery in patients with advanced fibrosis

BACKGROUND

Bariatric surgery is performed safely in non-alcoholic fatty liver disease (NAFLD) patients with minimal fibrosis (stage 1-2). However, the safety and potential benefits of bariatric surgery for NAFLD with advanced fibrosis (stage 3-4) remain unclear. This study was designed to compare the safety and efficacy of bariatric surgery in patients with biopsy proven advanced fibrosis to those with minimal fibrosis.

METHODS

All patients who underwent bariatric surgery between 2005 and 2014 and had evidence of NAFLD with fibrosis score 3-4 (advanced fibrosis) based on the staging system defined by Kleiner et al. on intraoperative liver biopsy were included and compared with patients who had fibrosis score 1-2 (minimal fibrosis). The groups were compared for length of hospital stay after bariatric surgery and incidence of postoperative complications over a follow-up period of 1 year. An improvement in hepatic function tests before and 1 year after surgery was used as a parameter to evaluate for NAFLD improvement.

RESULTS

Ninety-nine patients with F3-4 (group 1) and 198 patients with F1-2 (group 2) were included. Mean age (51.9 vs 50.1 years) and body mass index (46.4 vs 46.5 kg m^-2) were similar in the two groups. Median serum aspartate aminotransferase (43  vs 30 U l^-1; normal 10-40 U l^-1) and alanine aminotransferase (40.5 vs 34 U l^-1; normal 10-50 U l^-1) were significantly higher in group 1 and improved 1 year after surgery. Median length of hospital stay after surgery was higher in group 1 than that in group 2 (4 days vs 3 days; P-value=0.002). The proportion of patients developing postoperative complications over 1 year was similar in both groups (36.4% vs 32.8%; P-value=0.54).

CONCLUSIONS

Advanced fibrosis does not increase the risk of developing postoperative complications in medically optimized patients undergoing bariatric surgery. Improvement in serum transaminase levels suggests a reduction in hepatic necroinflammatory activity following bariatric surgery.

Laparoscopic gastric electrical stimulation for medically refractory diabetic and idiopathic gastroparesis

BACKGROUND

Gastric electrical stimulator (GES) implantation is effective in certain patients with gastroparesis; however, laparotomy is often employed for placement. The aim of this study is to review outcomes of patients who underwent laparoscopic GES therapy for diabetic and idiopathic gastroparesis at a large referral center.

METHODS

Patients who underwent GES (Enterra Therapy System; Medtronic, Minneapolis, MN) implantation with subsequent interrogation and programming between March 2001 and November 2011 were analyzed.

RESULTS

A total of 113 patients underwent GES placement or revision during the study period. One hundred eleven patients underwent primary GES at our institution, while two patients underwent GES generator revision at our institution. Primary operations were completed laparoscopically in 110 of 111 cases, with one conversion to laparotomy due to severe adhesions. At a mean follow-up of 27 months (1-113), symptom improvement was achieved in 91 patients (80 %) and was similar for both the diabetic and idiopathic subgroups. Need for supplemental nutrition (enteral and/or parental) decreased in both groups.

CONCLUSIONS

GES placement is feasible using a laparoscopic approach. Medical refractory gastroparesis in the diabetic and idiopathic groups had significant symptom improvement with no difference between the two groups. Need for supplemental nutrition is decreased following GES.

Intervieweffekte bei der Erhebung des Körpergewichts in Bevölkerungsumfragen

While surveying actually measured body weight is largely impractical in national surveys, self-reported weight is a simple and inexpensive method of collecting data. Previous research shows that data on reported body weight are falsified by systematic mis-reporting. This bias is said to be the consequence of the sensitive nature of information on body weight. Numerous studies on survey response suggest that certain modes of data collection are more conducive than others for probing sensitive information. This paper investigates the effect of the anonymous interviews, characteristics of the interviewer and respondents' familiarity with the survey, as factors that may impinge on reported body weight. Findings of this paper show that refusals to state the body weight are rare. Moreover, characteristics of interviewers account for only a small fraction of the variance in reported body weight. Yet the hypothesis that the absence of an interviewer in self-administered interviews increases reported body weight can be confirmed. This interview effect, however, occurred in men only. On average, male respondents in anonymous interview settings report on a body weight which is 1 kg more than they would report in other settings. The repeated participation of respondents in the Socio-Economic Panel Study (SOEP) increases their reported body weight accuracy which suggests a positive panel effect on respondents' willingness to disclose sensitive information.

Exocytosis in non-plasmolyzed and plasmolyzed tobacco pollen tubes : A freeze-fracture study

Exocytosis occurring during deposition of secondary wall material was studied by freeze-fracturing ultrarapidly frozen non-plasmolyzed and plasmolyzed tobacco pollen tubes. The secondary wall of tobacco pollen tubes shows a random orientation of microfibrils. This was observed directly on fractures through the tube wall and indirectly as imprints of microfibrils on fracture faces of the plasma membrane of non-plasmolyzed tubes. About half of the plasmatic fracture faces from non-plasmolyzed and plasmolyzed pollen tubes carried hexagonal arrays of intramembraneous particles in between randomly distributed particles. Deposition of secondary wall material was often accompanied by an undulated plasma membrane and the presence of membrane-bound vesicles in invaginations of the plasma membrane, between the plasma membrane and secondary wall and-especially in plasmolyzed tubes-within the secondary wall of tube flanks and wall cap. The findings are discussed in connection with published schemes of membrane behaviour during exocytosis.

Ultrastructure of cell wall and plugs of tobacco pollen tubes after chemical extraction of polysaccharides

Tobacco pollen tubes grown in vitro and from pollinated tobacco styles were treated by chemical solvents to remove one or more of the following polysaccharides from the tube walls: pectin (ethylenediamine tetraacetic acid); hemicellulose (alkali); callose (alkali; potassium hypochlorite); cellulose (cuprammonium); and all polysaccharides with exception of cellulose (H2O2/glacial acetic acid). Both the inner tube wall, which we had regarded as the secondary wall, and the plugs contained, in addition to callose, microfibrils of cellulose and "non-cellulosic" microfibrils that had "pectin-like" properties. When using the expressions callosic or callose layer and callose plugs in reference to pollen tubes, one should realize that they do not imply the exclusive presence of callose in the inner tube wall layer and its localized thickenings.

Cell wall formation in zoospores of Allomyces arbuscula. III. Carbohydrate composition of cell walls during development from meiospores to hyphae

Carbohydrate composition was determined in isolated cell walls of meiospores of Allomyces arbuscula after incubation for 15 min (encysted meiospores: cysts), 150 min (germlings: cysts + rhizoids) and 24 h (cysts + rhizoids + hyphae). The principal constituent in all cell wall samples is chitin, accounting for about 75% of the recovered carbohydrates. In addition, cell walls of all stages examined contain polysaccharides which release galactose, glucose, mannose, arabinose, xylose, fucose, and rhamnose on acid hydrolysis. While different developmental stages show minor quantitative changes in chitin, the ratio of galactose to glucose decreases sharply during differentiation of ungerminated cysts into germlings with rhizoids and hyphae. The increase in glucose is accompanied by a decrease in the amount of xylose and/or fucose and of galactose.

Cell wall formation in zoospores of Allomyces arbuscula. II. Development of surface structure of encysted haploid zoospores, rhizoids, and hyphae

Development of haploid meiospores of Allomyces arbuscula into germling cells with rhizoids and hyphae was followed during incubation in complete growth medium. The surface structure of encysted meiospores, rhizoids and hyphae before and after extraction of amorphous materials with ethanolic KOH was studied by means of carbon-platinum replicas. After 2--3 min incubation in complete medium 10% of the meiospores were surrounded by a cell wall containing microfibrils embedded in a matrix. Structure of cell walls of encysted meiospores, rhizoids, and hyphae differ from one another by the location of amorphous materials and by the arrangement of chitin microfibrils.

The Composition of Stigmatic Exudate from Lilium longiflorum: Labeling Studies with Myo-inositol, d-Glucose, and l-Proline

Stigmatic exudate, a secretion product recovered from the upper surface of Lilium longiflorum pistils, has been examined. Over 99% of the exudate is accounted for as water, carbohydrate, and protein. Exclusive of water, 95% is a high molecular weight, protein-containing polysaccharide composed of galactose, arabinose, rhamnose, glucuronic acid, and galacturonic acid.Detached pistils supplied with myo-inositol-U-(14)C, myo-inositol-2-(3)H, d-glucose-1-(14)C, or l-proline-U-(14)C produce labeled stigmatic exudate. When myo-inositol is supplied, the exudate is rich in labeled arabinose and uronic acids, but some label also recycles through the hexose phosphate pool of secreting cells, causing label to appear in galactose and rhamnose residues. When glucose is provided, galactose is the major constituent labeled but all of the other carbohydrate constituents are also labeled. Proline produces a pattern very similar to that obtained with glucose.Stigmatic exudate also contains a small amount of low molecular weight carbohydrate. If myo-inositol is used to label exudate, free labeled myo-inositol cannot be detected in the low molecular weight fraction until it has been subjected to acid hydrolysis. Similarly, if d-glucose is the source of label, free labeled glucose is found in the low molecular weight fraction only after acid hydrolysis.

Incorporation of label into pollen tube walls from myoinositol-labeled Lilium longiflorum pistils

Compatible and incompatible pollen tubes growing on detached Lilium longiflorum pistils which had been prelabeled with myoinositol-U-(14)C take up a portion of the label and utilize it for biosynthesis of tube wall substance. The label is transferred from pistil to pollen tubes apparently via the secretion products (exudate) of the pistil. The exudate thus appears to have a major nutritional role in pollen tube growth in vivo.

Inositol metabolism in plants. VII. Distribution and utilization of label from myoinositol-U 14C and -2-3H by detached flowers and pistils of Lilium longiflorum

When detached flowers or isolated pistils of Lilium longiflorum are given myoinositol-U-(14)C or -2-(3)H as dilute solution through the severed pedicel, label is quickly distributed by the vascular system. In the case of pistils, a pattern of labeling in ovary, style, and stigma is obtained which indicates that products of myoinositol metabolism are utilized in the biosynthesis of exudate (secretion product) of the stigma and style as well as for components of pistil cell walls. Pollination had no discernible effect on labeling pattern.

[Production and transport of the stigmatic exudate of petunia]

1. The production of the stigmatic exudate of Petunia is related to the endoplasmic reticulum. 2. In the cytoplasm the exudate is present in the form of droplets and is transported in this form to the plasmalemma. 3. The plasmalemma acts in transporting the exudate-droplets into the cellulose wall. 4. There is an accumulation of exudate-droplets in the intercellular system of the stigmatic tissue and in the pectin-rich wall layer of the epidermis. 5. The exudate-droplets flow together to form a film after penetrating the cuticle of the epidermis.