Anatomy of the neural fibers at the superior mesenteric artery-a cadaver study

PURPOSE Most surgeons perform right-sided semicircular clearance of the superior mesenteric artery (SMA) nerve plexus for pancreatic head carcinoma, presuming a linear course of the SMA nerve fibers. The hypothesis was that the SMA nerve plexus fibers follow a non-linear course, and the goal of the present study was to assess the neural fibers distribution along the SMA. METHODS The course of neural fibers along the retropancreatic and suprapancreatic SMA was assessed in 7 cadavers. RESULTS In the retropancreatic course of the vessel, the main nerve cords branch and form a large number of finer nerve branches performing an anti-clockwise rotation of slightly less than 90° around the SMA. Finer nerve branches are located rather close to the vessel, while the main nerve cords are localized in the loose connective tissue of the peripheral parts of the vascular sheath. Nerve fibers around the suprapancreatic SMA run as two main nerve cords framing the artery on the right lateral-ventral and the left lateral to lateral-dorsal side. CONCLUSION The rotation of the nerve fiber around the SMA indicates that a more radical resection of at least 180° of neural tissue around the SMA might be required to achieve tumor clearance in pancreatic cancer with perineural invasion at the uncinate margin

Microbial Colonization From the Fetus to Early Childhood—A Comprehensive Review

The development of the neonatal gastrointestinal tract microbiota remains a poorly understood process. The interplay between neonatal (gestational age, genetic background), maternal (mode of delivery, nutritional status) and environmental factors (antibiotic exposure, available nutrition) are thought to influence microbial colonization, however, the exact mechanisms are unclear. Derangements in this process likely contribute to various gastrointestinal diseases including necrotizing enterocolitis and inflammatory bowel disease. As such, enhanced understanding of microbiota development may hold the key to significantly reduce the burden of gastrointestinal disease in the pediatric population. The most debatable topics during microbial seeding and possible future treatment approaches will be highlighted in this review

SARS-CoV-2 receptor ACE2 gene expression in small intestine correlates with age

Gastrointestinal symptoms are common in COVID-19 patients, especially in younger patients. Our hypothesis was that intestinal SARS-CoV-2 receptor ACE2 expression depends on patients' age. We examined duodenal biopsies from 43 healthy human adults. ACE2 gene expression was directly correlated with age (Spearman's r = 0.317, p = 0.039). With each year, duodenal ACE2 expression increased by 0.083 RU. The higher intestinal ACE2 mRNA expression in older patients may impact on their susceptibility to develop intestinal symptoms

Statistics decrypted-a comprehensive review and smartphone-assisted five-step approach for good statistical practice

BACKGROUND Statistic scripts are often made by mathematicians and cryptic for clinicians or non-mathematician scientists. Nevertheless, almost all research projects necessitate the application of some statistical tests or at least an understanding thereof. The present review aims on giving an overview of the most common statistical terms and concepts. It further ensures good statistical practice by providing a five-step approach guiding the reader to the correct statistical test. METHODS AND RESULTS First, different types of variables and measurements to describe a data set with means of descriptive statistics are introduced. The basic thoughts and tools of interferential statistics are presented, and different types of bias are discussed. Then in the final paragraph, the most commonly used statistical tests are described. A smartphone app accessible via QR code finally guides the reader in five steps to the correct statistical test, depending on the data used in order to avoid commonly performed mistakes. CONCLUSIONS The five-step approach sets a new minimal standard for good statistical practice

Single Incision Pediatric Endoscopic Surgery: From Myth to Reality a Case Series

Laparoscopic surgery has continued to evolve to minimize access sites and scars in both the adult and pediatric populations. In children, single-incision pediatric endoscopic surgery (SIPES) has been shown to be effective, feasible, and safe with comparative results to multiport equivalents. Thus, the use of SIPES continues over increasingly complex cases, however, conceptions of its efficacy continue to vary greatly. In the present case series and discussion, we review the history of SIPES techniques and its current application today. We present this in the setting of five common myths about SIPES techniques: limitations against complex cases, restrictions to specialized training, increased morbidity outcomes, increased operative lengths, and increased operative costs. Regarding the myth of SIPES being limited in application to simple cases, examples were highlighted throughout the literature in addition to the authors’ own experience with three complex cases including resection of a lymphatic malformation, splenectomy with cholecystectomy, and distal pancreatectomy with splenectomy. A review of SIPES learning curves shows equivalent operative outcomes to multiport learning curves and advancements towards practical workshops to increase trainee familiarity can help assuage these aptitudes. In assessing comorbidities, adult literature reveals a slight increase in incisional hernia rates, but this does not correlate with single-incision pediatric data. In experienced hands, operative SIPES times average approximate multiport laparoscopic equivalents. Finally, regarding expenses, SIPES represents an equivalent alternative to laparoscopic techniques

Colostomy for perianal sepsis with ecthyma gangrenosum in immunocompromised children

BACKGROUND Perianal sepsis with ecthyma gangrenosum is a severe and potentially mutilating complication in immunocompromised children. Therapies include antimicrobial treatment, incision and drainage, generous tissue debridement, and skin transplantation. PROCEDURE We describe 3 children with acute lymphoblastic leukemia having sepsis with Pseudomonas aeruginosa in febrile neutropenia and severe perianal infections treated relatively early with a protective colostomy. Indications for colostomy were nonhealing wounds, and ceaseless pain. RESULTS All patients showed a rapid reduction of pain. Complete wound healing was seen in 2 patients, and considerable pain reduction and increased quality of life were seen in a third patient during palliative care. CONCLUSIONS These results suggest that a protective colostomy should be considered early in the management of immunocompromised children with ecthyma gangrenosum

ACE2 and gut amino acid transport

ACE2 is a type I membrane protein with extracellular carboxypeptidase activity displaying a broad tissue distribution with highest expression levels at the brush border membrane (BBM) of small intestine enterocytes and a lower expression in stomach and colon. In small intestinal mucosa, ACE2 mRNA expression appears to increase with age and to display higher levels in patients taking ACE-inhibitors (ACE-I). There, ACE2 protein heterodimerizes with the neutral amino acid transporter Broad neutral Amino acid Transporter 1 (B0AT1) (SLC6A19) or the imino acid transporter Sodium-dependent Imino Transporter 1 (SIT1) (SLC6A20), associations that are required for the surface expression of these transport proteins. These heterodimers can form quaternary structures able to function as binding sites for SARS-CoV-2 spike glycoproteins. The heterodimerization of the carboxypeptidase ACE2 with B0AT1 is suggested to favor the direct supply of substrate amino acids to the transporter, but whether this association impacts the ability of ACE2 to mediate viral infection is not known. B0AT1 mutations cause Hartnup disorder, a condition characterized by neutral aminoaciduria and, in some cases, pellagra-like symptoms, such as photosensitive rash, diarrhea, and cerebellar ataxia. Correspondingly, the lack of ACE2 and the concurrent absence of B0AT1 expression in small intestine causes a decrease in l-tryptophan absorption, niacin deficiency, decreased intestinal antimicrobial peptide production, and increased susceptibility to inflammatory bowel disease (IBD) in mice. Thus, the abundant expression of ACE2 in small intestine and its association with amino acid transporters appears to play a crucial role for the digestion of peptides and the absorption of amino acids and, thereby, for the maintenance of structural and functional gut integrity