Introduction
The aim of this study was to analyze the functional anatomy of the lateral collateral ligament complex (LCLC) and the surrounding forearm extensors.
Materials and methods
Using 81 human ...cadaveric upper extremities, the anatomy of the forearm extensors—especially the anconeus, supinator and extensor carpi ulnaris (ECU)—was analyzed. After removal of aforementioned extensors the functional anatomy of the LCLC was analyzed. The origin of the LCLC was evaluated for isometry. The insertion types of the lateral ulnar collateral ligament (LUCL) were analyzed and classified.
Results
The ECU runs parallel to the RCL to dynamically preserve varus stability. The supinator and anconeus muscle fibers coalesce with the LCLC and lengthen during pronation. The anconeus fibers run parallel to the LUCL in full flexion. The LCLC consists of the annular ligament (AL) and the isometric radial collateral ligament (RCL). During elbow flexion, its posterior branches (LUCL) tighten while the anterior branches loosen. When performing a pivot shift test, the loosened LUCL fibers do not fully tighten in full extension. The LUCL inserts along with the AL at the supinator crest. Three different insertion types could be observed.
Conclusions
The LUCL represents the posterior branch of the RCL rather than a distinct ligament. It is non-isometric and lengthens during elbow flexion. The RCL was found to be of vital importance for neutralization of posterolateral rotatory forces. Pronation of the forearm actively stabilizes the elbow joint as the supinator, anconeus and biceps muscle work in unison to increase posterolateral rotatory stability.
Abstract
Background
To access the risk of bowel resection in Crohn’s disease patients with enterocutaneous fistulae.
Methods
Consecutive patients undergoing intestinal resections for Crohn’ disease ...between 1992 and 2021 were included in the present prospective observational study. Exclusion criteria were: a) abdominoperineal resections for perianal disease, b) surgery for colorectal cancer complicating Crohn’s disease, c) abdominal surgery without intestinal resection (e.g. stoma formation or closure, mere adhesiolysis etc. Enterocutaneous fistulae occurring after previous bowel resection were named “postresection fistulae”, all other – “non-postresection fistulae”.
Results
750 patients were included. At all, 70 patients (9%) underwent intestinal resections due to enterocutaneous fistulae. The frequency of surgery for enterocutaneous fistula decreased significantly during the last decade of the study (1992-2000: 13% of surgeries, 2001-2010: 12% of surgeries, 2011-2021: 6% of surgeries; p=0.05). The postoperative intraabdominal septic complication rate was 15% (n=111), six patients (0.8%) died. The mortality rate was 7% (5 of 79%) in patients with enterocutaneous fistulae. All latter death occurred only in patients with postresection fistulae. By multivariate analysis, surgery for enterocutaneous fistula (Hazard ratio 27.4, 95% CI: 2.9 – 255.6; p=0.004), age of 50 years and older (Hazard ratio 13.2; 95% CI: 2.0 – 87.7; p=0.008) and presence of intraabdominal abscess (Hazard ratio 11.8; 95% CI: 1.2 – 116.5; p=0.035) were associated with an increased risk of postoperative death. Age over 50 years was associated with an increased risk of death in patients with enterocutaneous fistulae (mortality rate 20% vs. 3.6%, Hazard ratio 16.61; 95% CI: 1.28 – 216.07; p=0.032).
Conclusion
Surgery for enteroctunaeous fistulae still poses significant risks, specially, when they occurred after bowel resection and in older patients.
Abstract
Background
Preoperative factors - mainly patients’ condition and disease phenotype – are main determinants of postoperative outcome. However, those factors might be strongly dictated by ...regional traditions and treatment patterns of referring gastroenterologists. The present prospective observational study compared two German IBD-referral centers located in two different geographical regions regarding patients’ characteristics and postoperative outcome.
Methods
Consecutive patients referred to undergo intestinal resections at two different regional centers of IBD-surgery were included in present prospective observational study. Both surgical departments were headed by same surgeon, thus, decisions to perform surgery, preoperative routine and the postoperative management did not differ between hospitals. One hospital (Hospital 1) was located in Bavaria. Patients underwent intestinal surgery at this hospital between 2019 and 2021. The second hospital (Hospital 2) was located in North Rhine-Westphalia. All surgeries at Hospital 2 were performed 2022. The distance between both hospitals was about 600km.
Results
181 patients underwent bowel resections – 102 at Hospital 1 and 79 at Hospital 2. There were significant differences between both hospitals regarding preoperative variables: Azathioprine intake (8% vs. 23%, p=0.005), Steroid intake (13% vs. 29%, p=0.008) and presence of colonic disease (27% vs. 46%, p=0.013). Also, the frequency of some intraoperative procedures differed significantly: ostomy formation at surgery (16% vs. 29%, p=0.044), ileocolic resections (78% vs. 58%, p=0.001), colonic resections (15% vs. 34%, p=0.003). Postoperatively, there was difference in incidence of postoperative ileus (8% vs. 18%, p=0.041). Also, overall complication rate was lower in Hospital 1 (21% vs. 31%), however, the difference was not statistically significant (p=0.12).
Conclusion
Different referral patterns might exist between various hospitals and regions leading to different perioperative outcomes. This should be taken in consideration when results of studies are compared.
Abstract
Background
Appendectomy is suggested to improve the course of the disease in many patients with refractory Ulcerative Colitis (UC). Present prospective observational study demonstrates ...short-term outcomes after an appendectomy in 16 patients with refractory UC.
Methods
Between 5/2022 and 11/2022, 16 selected patients underwent appendectomy for refractory UC. Only patients with dysplasia or cancer were excluded. However, an appendectomy was not proposed to patients with severe sarcopenia or severe anemia, except in one case of severe acute colitis. The appendectomy was performed without the removal of the cecal base.
Results
Mean age was 35 years (18 to 59 years), there were 9 male patients. Nine had a pancolitis. Eight patients were referred to colectomy (50%). Eight were taking steroids (10mg to 75mg), all but three were under biological treatment. Median preoperative Mayo score was 6.5. Two patients had severe anemia (hemoglobin <10 g/dl). The appendix appeared to be inflamed visually in 3 patients (19%) and histologically in 10 patients (62%). Hospital stay was median 2 days, there was one wound infection at the port site. A significant improvement of disease symptoms was reported by 14 patients during the first 2 weeks. At the end of the follow-up period of 1 to 6 months, no colectomy has been performed.
Conclusion
The majority of patients with refractory UC demonstrates rapid clinical response to an appendectomy. Longer observation is necessary in order to determine whether the rapid response translates to a favourable long-term outcome.
Abstract
Background
Appendectomy is suggested to improve the course of the disease in many patients with refractory ulcerative colitis (UC). The present prospective observational study demonstrates ...middle-term outcomes after an appendectomy in 26 patients with refractory UC.
Methods
Between 5/2022 and 2/2023, 26 selected patients underwent appendectomy for refractory UC. Refractory UC was defined as a failure of at least one biologic therapy. Patients with Dysplasia or Cancer were excluded. The appendectomy was performed without the removal of the cecal base. Primary Endpoint of the study was the Mayo clinical score (MCS) at 6 months after the appendectomy. Secondary Endpoint was the “Treatment failure” which was defined as occurrence of one of the following events during the first 6 months after appendectomy: 1) high-dosed steroid treatment, 2) change of biologic treatment, 3) colectomy.
Results
Mean age was 35 years (18 to 59 years) and there were 11 female patients. 15 had a pancolitis (58%). Twelve were taking steroids (46%). Median number of biologic therapies taken by patients prior to surgery was 3 (range, 1-5). One patient underwent surgery for sever acute UC. The appendix appeared to be inflamed histologically in 16 patients (62%). Hospital stay was median 2 days, there was one wound infection at the port site and one postoperative hematoma. A significant improvement of disease symptoms was reported by 21 patients during the first 4 weeks (81%). At 6 months, MCS improved from mean 6.4 to 4.5 (p=0.057). Therapy failure was observed in 15 patients (58%) – two underwent colectomy, 11 needed at least one high-dose steroid treatment and biologic therapy was changed due to refractory symptoms in 9 patients. Intake of JAK-inhibitors at the time of appendectomy was the only factor to be associated with lower probability of treatment failure (30% vs. 75%, p=0.043). The only patient undergoing appendectomy for severe acute UC was free of symptoms 14 months after surgery.
Conclusion
The majority of patients with refractory UC demonstrated rapid clinical response to the appendectomy. After 6 months, more than 40% of patients did not experience disease flares necessitating intensification of treatment.
Located between the on-detector front-end electronics and the global data acquisition system (DAQ), the off-detector electronics of the CMS electromagnetic calorimeter (ECAL) is involved in both ...detector readout and trigger system. Working at 40 MHz, the trigger part must, within ten clock cycles, receive and deserialize the data of the front-end electronics, encode the trigger primitives using a nonlinear scale, assure time alignment between channels using a histogramming technique and send the trigger primitives to the regional trigger. In addition, it must classify trigger towers in three classes of interest and send this classification to the readout part. The readout part must select the zero suppression level to be applied depending on the regions of interest determined from the trigger tower classification, deserialize front-end data coming from high-speed (800 Mb/s) serial links, check their integrity, apply zero suppression, build the event and send it to the DAQ, monitor the buffer occupancy and send back pressure to the trigger system when required, provide data spying and monitoring facilities for the local DAQ. The system, and especially the data link speed, the latency constraints and the bit-error rate requirements have been validated on prototypes. Part of the system is about to go to production.
Locomotion in
Caenorhabditis elegans requires force transmission through a network of proteins linking the skeletal muscle, via an intervening basal lamina and epidermis (hypodermis), to the cuticle. ...Mutations in
mua-6 result in hypodermal rupture, muscle detachment from the bodywall, and progressive paralysis. It is shown that
mua-6 encodes the cytoplasmic intermediate filament (cIF) A2 protein and that a MUA-6/IFA-2::GFP fusion protein that rescues the presumptive
mua-6 null allele localizes to hypodermal hemidesmosomes. This result is consistent with what is known about the function of cIFs in vertebrates. Although MUA-6/IFA-2 is expressed embryonically, and plays an essential postembryonic role in tissue integrity, it is not required for embryonic development of muscle–cuticle linkages nor for the localization of other cIFs or hemidesmosome-associated proteins in the embryo. Finally, the molecular lesion in the
mua-6(rh85) allele suggests that the head domain of the MUA-6/IFA-2 is dispensable for its function.
The G protein-coupled receptor (GPCR) G2A (for G2 accumulation) was identified as a stress-inducible antiproliferative cell cycle regulator. Targeted G2A gene deletion in mice resulted in systemic ...lupus erythematosus-like and atherosclerotic lesion phenotypes. These findings suggested that G2A may be a therapeutic target for cancers and autoimmune and cardiovascular diseases. The G2A receptor is cytotoxic upon ectopic expression, and its cognate ligand has not been identified, making it difficult to generate a cell line for screening using a conventional approach. The function of human G2A remains obscure. Here we show that by using an inducible T-REx (Invitrogen, Carlsbad, CA) expression system an inducible G2A functional cell-based beta-lactamase reporter assay could be developed using the constitutive activity of the receptor. Furthermore, G2A expression levels can be controlled under this inducible system to avoid the expression artifacts of conventional approaches using constitutive expression vectors. This stable cell line expressing the human G2A receptor was screened against a chemical library containing 740,000 compounds, and small molecules showing selective agonistic activity on G2A were identified. We believe the strategy employed here for G2A should be applicable to other "intractable" GPCRs where target gene expression results in cytotoxic and/or high constitutive activities.
A prototype of the trigger and digital processing electronics for the electromagnetic calorimeter of the CMS experiment, coupled to a prototype of the PbWO
4 crystal calorimeter, was tested during ...summer 1996 in the H4 beamline at the CERN SPS. A very successful operation was achieved for this system, which runs in synchronous and pipelined mode at the LHC clock frequency, and performs the basic trigger and data acquisition functions needed in the CMS electromagnetic calorimeter. The performance of the trigger front-end electronics is well within the established requirements: a highly efficient bunch-crossing identification (>99.9%), a good trigger-energy resolution (
σ/E∼9%/
E
⊕2%
) and a highly efficient electron cluster shape identification (∼99%) have been achieved. The FERMI digitising system based on a dynamic analog compressor and a sampling ADC showed a very good performance, in particular the energy resolution for 150
GeV electrons was 0.54%, equal to the resolution obtained with a conventional charge integration ADC system.
Normal locomotion of the nematode Caenorhabditis elegans requires transmission of contractile force through a series of mechanical linkages from the myofibrillar lattice of the body wall muscles, ...across an intervening extracellular matrix and epithelium (the hypodermis) to the cuticle. Mutations in mua-3 cause a separation of the hypodermis from the cuticle, suggesting this gene is required for maintaining hypodermal-cuticle attachment as the animal grows in size postembryonically. mua-3 encodes a predicted 3,767 amino acid protein with a large extracellular domain, a single transmembrane helix, and a smaller cytoplasmic domain. The extracellular domain contains four distinct protein modules: 5 low density lipoprotein type A, 52 epidermal growth factor, 1 von Willebrand factor A, and 2 sea urchin-enterokinase-agrin modules. MUA-3 localizes to the hypodermal hemidesmosomes and to other sites of mechanically robust transepithelial attachments, including the rectum, vulva, mechanosensory neurons, and excretory duct/pore. In addition, it is shown that MUA-3 colocalizes with cytoplasmic intermediate filaments (IFs) at these sites. Thus, MUA-3 appears to be a protein that links the IF cytoskeleton of nematode epithelia to the cuticle at sites of mechanical stress.
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