Lichtenstein Versus Total Extraperitoneal Patch Plasty Versus Transabdominal Patch Plasty Technique for Primary Unilateral Inguinal Hernia Repair: A Registry-based, Propensity Score-matched Comparison of 57,906 Patients.

OBJECTIVE: Outcome comparison of the Lichtenstein, total extraperitoneal patch plasty (TEP), and transabdominal patch plasty (TAPP) techniques for primary unilateral inguinal hernia repair. BACKGROUND: For comparison of these techniques the number of cases included in meta-analyses of randomized controlled trials is limited. There is therefore an urgent need for more comparative data. METHODS: In total, 57,906 patients with a primary unilateral inguinal hernia and 1-year follow up from the Herniamed Registry were selected between September 1, 2009 and February 1, 2015. Using propensity score matching, 12,564 matched pairs were formed for comparison of Lichtenstein versus TEP, 16,375 for Lichtenstein versus TAPP, and 14,426 for TEP versus TAPP. RESULTS: Comparison of Lichtenstein versus TEP revealed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.4% vs 1.7%; P < 0.001), complication-related reoperations (1.1% vs 0.8%; P = 0.008), pain at rest (5.2% vs 4.3%; P = 0.003), and pain on exertion (10.6% vs 7.7%; P < 0.001). TEP had disadvantages in terms of the intraoperative complications (0.9% vs 1.2%; P = 0.035). Likewise, comparison of Lichtenstein versus TAPP showed disadvantages for the Lichtenstein operation with regard to the postoperative complications (3.8% vs 3.3%; P = 0.029), complication-related reoperations (1.2% vs 0.9%; P = 0.019), pain at rest (5% vs 4.5%; P = 0.029), and on exertion (10.2% vs 7.8%; P < 0.001). CONCLUSIONS: TEP and TAPP were found to have advantages over the Lichtenstein operation.

Conformational µ-Conotoxin PIIIA Isomers Revisited: Impact of Cysteine Pairing on Disulfide-Bond Assignment and Structure Elucidation.

Peptides and proteins carrying high numbers of cysteines can adopt various 3D structures depending on their disulfide connectivities. The unambiguous verification of such conformational isomers with more than two disulfide bonds is extremely challenging, and experimental strategies for their unequivocal structural analysis are largely lacking. We synthesized all 15 possible isomers of the 22mer conopeptide µ-PIIIA and applied 2D NMR spectroscopy and MS/MS for the elucidation of its structure. This study provides intriguing insights in how the disulfide connectivity alters the global fold of a toxin. We also show that analysis procedures involving comprehensive combinations of conventional methods are required for the unambiguous assignment of disulfides in cysteine-rich peptides and proteins and that standard compounds are crucially needed for the structural analysis of such complex molecules.

Dynamics of the regulation of Hsp90 by the co-chaperone Sti1.

In eukaryotic cells, Hsp90 chaperones assist late folding steps of many regulatory protein clients by a complex ATPase cycle. Binding of clients to Hsp90 requires prior interaction with Hsp70 and a transfer reaction that is mediated by the co-chaperone Sti1/Hop. Sti1 furthers client transfer by inhibiting Hsp90's ATPase activity. To better understand how Sti1 prepares Hsp90 for client acceptance, we characterized the interacting domains and analysed how Hsp90 and Sti1 mutually influence their conformational dynamics using hydrogen exchange mass spectrometry. Sti1 stabilizes several regions in all three domains of Hsp90 and slows down dissociation of the Hsp90 dimer. Our data suggest that Sti1 inhibits Hsp90's ATPase activity by preventing N-terminal dimerization and docking of the N-terminal domain with the middle domain. Using crosslinking and mass spectrometry we identified Sti1 segments, which are in close vicinity of the N-terminal domain of Hsp90. We found that the length of the linker between C-terminal dimerization domain and the C-terminal MEEVD motif is important for Sti1 association rates and propose a kinetic model for Sti1 binding to Hsp90.

Self-Gripping Meshes for Lichtenstein Repair. Do We Need Additional Suture Fixation?

BACKGROUND: The Lichtenstein repair is a frequently used treatment of inguinal hernias. In recent years, there has been an increasing tendency to apply self-gripping meshes (s.g). In many cases, additional suture of the mesh is carried out; however, it is uncertain what the benefits or potential risks of this actually are. METHODS: The evaluation was undertaken on the basis of the Herniamed register, and covered all unilateral Lichtenstein operations between 01.09.2009 up to 30.09.2013. The analysis only included patients with whom s.g. meshes with resorbable micro hooks had been used (Progrip(®), Covidien) and who had undergone a full 1-year follow-up examination (80.15 %). RESULTS: In total, 2095 patients were suitable for analysis, of which 816 (38.95 %) cases received an additional suture fixation (Fix). With increasing hernia size, more frequent fixation took place (29.97 % of hernias <1.5 cm vs. 46.65 % of hernias >3 cm, p < 0.001). The recurrence rates 1 year after surgery did not show any significant differences (Fix. 0.86 % vs. No Fix. 1.17 %; p = 0.661) with and without fixation, even when being adjusted for covariables. Likewise, no differences were noted in terms of postoperative complications (Fix. 5.15 % vs. No Fix. 5.08 %; p = 1.0). In addition, the numbers of patients needing to be treated after 1 year for chronic pain were also comparable (Fix. 2.33 % vs. No Fix. 2.97 %; p = 0.411). CONCLUSION: Within the group that did not have additional suture fixation of self-gripping meshes (No Fix.), the length of operations was on average 8 min shorter (p < 0.001). No differences could be observed in terms of postoperative complications, treatment requiring chronic pain and recurrence rates.

Dynamic magnetic resonance imaging evaluation of pelvic reconstruction with porcine dermal collagen mesh following extra-levator abdominoperineal excision for primary rectal cancer.

PURPOSE: Extra-levator abdominoperineal excision for rectal cancer includes resection of the levator ani muscle and therefore makes pelvic reconstruction advisable. The aim of our study was to evaluate morphologic and functional long-term results of pelvic floor augmentation with porcine dermal collagen mesh by dynamic magnetic resonance imaging and clinical examination. METHODS: Twenty consecutive patients underwent perineal reconstruction with porcine dermal collagen mesh following extra-levator abdominoperineal excision for primary rectal adenocarcinoma with curative intent between 2009 and 2012. Patient perioperative and postoperative data were collected prospectively. There were one cancer-related and two noncancer-related deaths in the follow-up period, and another three patients refused the dynamic magnetic resonance imaging. RESULTS: Fourteen patients were included in the study. The median time period from surgery to dynamic magnetic resonance imaging and clinical examination was 31 months (range 19-56). Wound infections were observed in 43% (6 of 14) of these patients in the postoperative period, but no mesh had to be removed. No focal mesh defect, no damage on the suture line, and no perineal hernia were detected on dynamic magnetic resonance imaging. Clinical examination revealed no pathological findings in any patient. CONCLUSIONS: The implantation of a porcine dermal collagen mesh is an effective and reliable option for pelvic floor reconstruction after extra-levator abdominoperineal excision. Despite a high incidence of primary wound infections, the healing rate was satisfactory, no mesh had to be removed, and long-term stability could be achieved.

Changes in the Surgical Management of Parastomal Hernias Over 15 Years: Results of 135 Cases.

BACKGROUND: Over the years, various open and laparoscopic approaches toward the repair of parastomal hernias (PSH) have been described. The variety of published techniques itself can be seen as an indicator for the often low level of satisfaction reached with the surgical procedures. METHODS: From January 1999 to January 2014, we assessed all cases of PSH repair performed at the three participating surgical departments in a retrospective analysis. The results were evaluated with regard to different surgical techniques focusing on complications and recurrences. RESULTS: One hundred and thirty-five individuals could be included in the analysis. They were operated on with eight different surgical techniques. Laparoscopic procedures were carried out in 46.7 % (63/135) of the cases. Median follow-up was 54 months (12-146 months). We found 44 cases of recurrence (32.6 %) and 24 (17.8 %) of the patients experienced perioperative complications and 12 of them needed to return to theater. Fourteen of the 135 patients (10.4 %) were operated as emergency cases which were associated with a mortality of 28.6 % (4/14). In case of elective PSH repair, no mortality occured. CONCLUSION: The results achieved by direct suture or the use of incised flat meshes for the repair of PSH were poor with these procedures having unacceptably high recurrence rates. With regard to the latter ostomy revision through three-dimensional funnel-shaped meshes and the laparoscopic sandwich technique showed the best results. Emergency procedures were linked to a dramatic increase in morbidity and mortality (p < 0.001).

Prevention of subcutaneous seroma formation in open ventral hernia repair using a new low-thrombin fibrin sealant.

BACKGROUND: Seroma formation is a frequent postoperative complication following open ventral hernia repair (OVHR), especially in cases requiring wide subcutaneous dissection (WSD). The aim of this study was to evaluate the effectiveness of a new low-thrombin fibrin sealant for seroma prevention. METHODS: A total of 60 consecutive patients with median incisional hernias who required OVHR with WSD of at least 100 cm(2) were included in the prospective non-randomized study. The fibrin glue group (FG) comprised 30 patients who had undergone OVHR with sublay mesh placement as well as subcutaneous application of low-thrombin fibrin sealant. This cohort of patients was compared with a control group (CG) of 30 consecutive patients who had previously undergone OVHR without prevention of seroma formation with regard to outcome measures such as seroma formations and wound complications. RESULTS: Though the median extent of subcutaneous dead space was larger in the FG than in the CG (229 vs.174 cm(2); p = 0.012), seroma formation occurred in three of the FG versus 16 of the CG patients (p = 0.003). Postoperative wound complications occurred in two of the FG versus nine of the CG patients (p = 0.002). Four patients in the CG and none in the FG required re-operation within 30 days (p < 0.001). CONCLUSION: The use of a new low-thrombin fibrin glue demonstrated a protective effect against formation of seromas and decreased the rate of wound complications in OVHR, with consecutive shorter length of hospital stay (5.8 vs. 10.4 days; p = 0.04).

Relevance of surgery after embolization of gastrointestinal and abdominal hemorrhage.

BACKGROUND: Gastrointestinal and abdominal bleeding can lead to life-threatening situations. Embolization is considered a feasible and safe treatment option. The relevance of surgery has thus diminished in the past. The aim of the present study was to evaluate the role of surgery in the management of patients after embolization. METHODS: We performed a retrospective single-center analysis of outcomes after transarterial embolization of acute abdominal and gastrointestinal hemorrhage between January 2009 and December 2012 at the Sisters of Charity Hospital, Linz. Patients were divided into three groups, as follows: upper gastrointestinal bleeding (UGIB), lower gastrointestinal bleeding (LGIB), and abdominal hemorrhage. RESULTS: Fifty-four patients with 55 bleeding events were included. The bleeding source could be localized angiographically in 80 %, and the primary clinical success rate of embolization was 81.8 % (45/55 cases). Early recurrent bleeding (<30 days) occurred in 18.2 % (10/55) of the patients, and delayed recurrent hemorrhage (>30 days) developed in 3.6 % (2/55). The mean follow-up was 8.4 months, and data were available for 85.2 % (46/54) of the patients. Surgery after embolization was required in 20.4 % of these patients (11/54). Failure to localize the bleeding site was identified as predictive of recurrent bleeding (p = 0.009). More than one embolization effort increased the risk of complications (p = 0.02) and rebleeding (p = 0.07). CONCLUSIONS: Surgery still has an important role after embolization in patients with gastrointestinal and abdominal hemorrhage. One of five patients required surgery in cases of early and delayed rebleeding or because of ischemic complications (2/55 both had ischemic damage of the gallbladder) and bleeding consequences.

Refined LexA transactivators and their use in combination with the Drosophila Gal4 system.

The use of binary transcriptional systems offers many advantages for experimentally manipulating gene activity, as exemplified by the success of the Gal4/UAS system in Drosophila. To expand the number of applications, a second independent transactivator (TA) is desirable. Here, we present the optimization of an additional system based on LexA and show how it can be applied. We developed a series of LexA TAs, selectively suppressible via Gal80, that exhibit high transcriptional activity and low detrimental effects when expressed in vivo. In combination with Gal4, an appropriately selected LexA TA permits to program cells with a distinct balance and independent outputs of the two TAs. We demonstrate how the two systems can be combined for manipulating communicating cell populations, converting transient tissue-specific expression patterns into heritable, constitutive activities, and defining cell territories by intersecting TA expression domains. Finally, we describe a versatile enhancer trap system that allows swapping TA and generating mosaics composed of Gal4 and LexA TA-expressing cells. The optimized LexA system facilitates precise analyses of complex biological phenomena and signaling pathways in Drosophila.

Photoinduced Amyloid Fibril Degradation for Controlled Cell Patterning.

Amyloid-like fibrils are a special class of self-assembling peptides that emerge as a promising nanomaterial with rich bioactivity for applications such as cell adhesion and growth. Unlike the extracellular matrix, the intrinsically stable amyloid-like fibrils do not respond nor adapt to stimuli of their natural environment. Here, a self-assembling motif (CKFKFQF), in which a photosensitive o-nitrobenzyl linker (PCL) is inserted, is designed. This peptide (CKFK-PCL-FQF) assembles into amyloid-like fibrils comparable to the unsubstituted CKFKFQF and reveals a strong response to UV-light. After UV irradiation, the secondary structure of the fibrils, fibril morphology, and bioactivity are lost. Thus, coating surfaces with the pre-formed fibrils and exposing them to UV-light through a photomask generate well-defined areas with patterns of intact and destroyed fibrillar morphology. The unexposed, fibril-coated surface areas retain their ability to support cell adhesion in culture, in contrast to the light-exposed regions, where the cell-supportive fibril morphology is destroyed. Consequently, the photoresponsive peptide nanofibrils provide a facile and efficient way of cell patterning, exemplarily demonstrated for A549, Chinese Hamster Ovary, and Raw Dual type cells. This study introduces photoresponsive amyloid-like fibrils as adaptive functional materials to precisely arrange cells on surfaces.

Case Report: Adult Right-Sided Bochdalek Hernia Complicated by Intrathoracic Bowel Perforation.

Right-sided Bochdalek hernia is a mostly congenital condition of the diaphragm caused by a persistence of the pleuroperitoneal cavity and a rare disease in adults. As it often presents as an emergent situation, urgent diagnostics and surgical intervention are essential to reduce morbidity and mortality rates. Choosing the right surgical approach (abdominal, thoracic, or a combination of both) can be very challenging for clinicians. Here, we report a case of a 40-year-old woman, who presented with severe abdominal pain and tachypnoea. Imaging revealed a right-sided Bochdalek hernia. Emergency laparotomy was performed followed by reduction of hernia content, right-sided hemicolectomy, and side-to-side anastomosis from the ileum to the transverse colon due to intestinal ischemia and intrathoracic bowel perforation. The post-operative course was complicated by a pleural empyema. Therefore, the patient underwent thoracotomy. One year after surgical repair the patient had no recurrence. Here, we discuss feasible approaches for the surgical management of complicated Bochdalek hernias.

Cell-Instructive Surface Gradients of Photoresponsive Amyloid-like Fibrils.

Gradients of bioactive molecules play a crucial role in various biological processes like vascularization, tissue regeneration, or cell migration. To study these complex biological systems, it is necessary to control the concentration of bioactive molecules on their substrates. Here, we created a photochemical strategy to generate gradients using amyloid-like fibrils as scaffolds functionalized with a model epitope, that is, the integrin-binding peptide RGD, to modulate cell adhesion. The self-assembling ß-sheet forming peptide (CKFKFQF) was connected to the RGD epitope via a photosensitive nitrobenzyl linker and assembled into photoresponsive nanofibrils. The fibrils were spray-coated on glass substrates and macroscopic gradients were generated by UV-light over a centimeter-scale. We confirmed the gradient formation using matrix-assisted laser desorption ionization mass spectroscopy imaging (MALDI-MSI), which directly visualizes the molecular species on the surface. The RGD gradient was used to instruct cells. In consequence, A549 adapted their adhesion properties in dependence of the RGD-epitope density.

Trends in Emergent Groin Hernia Repair-An Analysis From the Herniamed Registry.

Introduction: While the proportion of emergency groin hernia repairs in developed countries is 2.5-7.7%, the percentage in developing countries can be as high as 76.9%. The mortality rate for emergency groin hernia repair in developed countries is 1.7-7.0% and can rise to 6-25% if bowel resection is needed. In this present analysis of data from the Herniamed Registry, patients with emergency admission and operation within 24 h are analyzed. Methods: Between 2010 and 2019 a total of 13,028 patients with emergency admission and groin hernia repairs within 24 h were enrolled in the Herniamed Registry. The outcome results were assigned to the year of repair and summarized as curves. The total patient collective is broken down into the subgroups with pre-operative manual reduction (taxis) of the hernia content, operative reduction of the hernia content without bowel resection and with bowel resection. The explorative Fisher's exact test was used for statistical assessment of significant differences with Bonferroni adjustment for multiple testing. Results: The proportion of emergency admissions with groin hernia repair within 24 h was 2.7%. The percentage of women across the years was consistently 33%. The part of femoral hernias was 16%. The proportion of patients with pre-operative reduction (taxis) remained unchanged at around 21% and the share needing bowel resection was around 10%. The proportion of TAPP repairs rose from 21.9% in 2013 to 38.0% in 2019 (p < 0.001). Between the three groups with pre-operative taxis, without bowel resection and with bowel resection, highly significant differences were identified between the patients with regard to the rates of post-operative complications (4% vs. 6.5% vs. 22.7%; p < 0.0001), complication-related reoperations (1.9% vs. 3.8% vs. 17.7%; p < 0.0001), and mortality rate (0.3% vs. 0.9% vs. 7.5%; p < 0.001). In addition to emergency groin hernia repair subgroups female gender and age ≥66 years are unfavorable influencing factors for perioperative outcomes. Conclusion: For patients with emergency groin hernia repair the need for surgical reduction or bowel resection, female gender and age ≥66 years have a highly significantly unfavorable influence on the perioperative outcomes.

Recognition and ER Quality Control of Misfolded Formylglycine-Generating Enzyme by Protein Disulfide Isomerase.

Multiple sulfatase deficiency (MSD) is a fatal, inherited lysosomal storage disorder characterized by reduced activities of all sulfatases in patients. Sulfatases require a unique post-translational modification of an active-site cysteine to formylglycine that is catalyzed by the formylglycine-generating enzyme (FGE). FGE mutations that affect intracellular protein stability determine residual enzyme activity and disease severity in MSD patients. Here, we show that protein disulfide isomerase (PDI) plays a pivotal role in the recognition and quality control of MSD-causing FGE variants. Overexpression of PDI reduces the residual activity of unstable FGE variants, whereas inhibition of PDI function rescues the residual activity of sulfatases in MSD fibroblasts. Mass spectrometric analysis of a PDI+FGE variant covalent complex allowed determination of the molecular signature for FGE recognition by PDI. Our findings highlight the role of PDI as a disease modifier in MSD, which may also be relevant for other ER-associated protein folding pathologies.

Hyphenated LC-MALDI-ToF/ToF and LC-ESI-QToF approach in proteomic characterization of honeybee venom.

To increase in the depth characterization of venom proteome of Apis mellifera the hyphenated LC-MALDI-ToF/ToF-MS (liquid chromatography-matrix-assisted laser desorption/ionization-time of flight/time of flight tandem mass spectrometry) and LC-ESI-QToF-MS (liquid chromatography-electrospray ionization-quadrupole time of flight tandem mass spectrometry) techniques combined with combinatorial peptide ligand library enrichment method is proposed in this study. The novel approach simplifies pretreatment protocol in venom investigation. By using the protein preparation kit with sequential multi-step elution, the honeybee venom was dispensed into four different fractions. In total 269 proteins were detected, among these 49 honeybee toxins, allergens and components involved in mechanism of envenoming belonging to venom enzyme classes of esterases, proteases/peptidases, protease inhibitors, hydrolases and major royal jelly proteins. Moreover 5 additional putative toxins were identified. Their role in envenoming process was discussed. We concluded that different mass spectrometry techniques increased the detection of the honeybee venom proteins, underscoring the complementary character of analytical methods. The combination of MALDI and ESI ionization has resulted in numerous proteins identifications, not possible to reach with single proteomic technique. The study will contribute to broadening the knowledge about the complexity of honeybee venom. The newly identified proteins may serve not only as toxins and allergens, but also as substances with potential pharmacological activity. Although, the most detected proteins belong to trace elements of honeybee venom without toxic activity or action on vital system of victims, they should be taken into account in characterization of living organism response on Apis mellifera sting.

Use of polymorphisms in the γ-gliadin gene of spelt and wheat as a tool for authenticity control.

Partial sequencing of the γ-gliadin gene of 62 spelt and 14 soft wheat cultivars was performed. Fifty-six of the 62 spelt cultivars and 13 of the 14 soft wheat cultivars were shown to exhibit the typical spelt or soft wheat γ-gliadin sequence, respectively. Exceptions were ascribed to crossbreeding of soft wheat and spelt. Using the typical soft wheat γ-gliadin sequence, two alternative DNA-based analytical methods were developed for the detection and quantification of spelt flour "adulteration" with soft wheat. A simple and fast detection of soft wheat in spelt flours could be achieved by restriction fragment length (RFLP) analysis. In combination with lab-on-a-chip capillary gel electrophoresis (LOC-CE) the soft wheat proportion could be estimated. Heteroduplex formation served as additional confirmation for the presence of spelt besides soft wheat. Hence, RFLP-LOC-CE constitutes a perfect analysis tool for the quality control of cereal seeds and pure cultivars. A precise quantification of soft wheat "adulterations" in spelt flour down to 1% could be achieved by the developed real-time PCR method. The calibration parameters of the real-time PCR assay fulfilled the minimum performance requirements of the European Network of GMO (genetically modified organisms) Laboratories (ENGL).

Human myocardial protein pattern reveals cardiac diseases.

Proteomic profiles of myocardial tissue in two different etiologies of heart failure were investigated using high performance liquid chromatography (HPLC)/Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Right atrial appendages from 10 patients with hemodynamically significant isolated aortic valve disease and from 10 patients with isolated symptomatic coronary heart disease were collected during elective cardiac surgery. As presented in an earlier study by our group (Baykut et al., 2006), both disease forms showed clearly different pattern distribution characteristics. Interesting enough, the classification patterns could be used for correctly sorting unknown test samples in their correct categories. However, in order to fully exploit and also validate these findings there is a definite need for unambiguous identification of the differences between different etiologies at molecular level. In this study, samples representative for the aortic valve disease and coronary heart disease were prepared, tryptically digested, and analyzed using an FT-ICR MS that allowed collision-induced dissociation (CID) of selected classifier masses. By using the fragment spectra, proteins were identified by database searches. For comparison and further validation, classifier masses were also fragmented and analyzed using HPLC-/Matrix-assisted laser desorption ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry. Desmin and lumican precursor were examples of proteins found in aortic samples at higher abundances than in coronary samples. Similarly, adenylate kinase isoenzyme was found in coronary samples at a higher abundance. The described methodology could also be feasible in search for specific biomarkers in plasma or serum for diagnostic purposes.