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Anatomical Record (Hoboken, N.J. : 2007) Nov 2018The gastrointestinal tract of the alpaca (Vicugna pacos) is most efficiently adapted to its habitat at high altitudes. Alpacas, just like ruminants, feed on hardly...
The gastrointestinal tract of the alpaca (Vicugna pacos) is most efficiently adapted to its habitat at high altitudes. Alpacas, just like ruminants, feed on hardly digestible forage. However, it has been demonstrated that the anatomy of the camelid digestive tract has developed independently of ruminants and not in homology to them. Despite a long history of domestication and an increasing number of animals worldwide, little research has been done on the intestinal anatomy of alpacas. The purpose of this study was to describe the anatomical features of the alpaca's intestines and to explain anatomical peculiarities in the context of evolutionary function and morphology. Another goal of this study was the demonstration of weaknesses of the intestinal anatomy predisposing alpacas to certain clinical presentations. Six animals were used for dissection. The basic structure of the intestines was comparable to that in ruminants. However, a number of characteristic peculiarities were found in alpacas, like the duodenal ampulla and the proximal and distal loop of the ascending colon. The jejunum and ileum, unlike those of ruminants, had their own mesentery largely separated from the ascending mesocolon. The main blood supply was provided by the cranial and caudal mesenteric artery. The particular lymph nodes were located along the branches of these two arteries. The spiral colon seemed to play a major role in intestinal digestion and water resorption. The size of the distal fermentation chamber allows the presumption that alpacas belong to the group of animals practicing a fractionated fermentation in the proximal and distal fermentation chambers. Anat Rec, 301:1840-1851, 2018. © 2018 Wiley Periodicals, Inc.
Topics: Adaptation, Physiological; Animals; Camelids, New World; Ecosystem; Feeding Behavior; Female; Intestines; Male
PubMed: 30288956
DOI: 10.1002/ar.23863 -
Journal of Cellular and Molecular... Dec 2018Colon crypts are recognized as a mechanical and biochemical Turing patterning model. Colon epithelial Caco-2 cell monolayer demonstrated 2D Turing patterns via force...
Colon crypts are recognized as a mechanical and biochemical Turing patterning model. Colon epithelial Caco-2 cell monolayer demonstrated 2D Turing patterns via force analysis of apical tight junction live cell imaging which illuminated actomyosin meshwork linking the actomyosin network of individual cells. Actomyosin forces act in a mechanobiological manner that alters cell/nucleus/tissue morphology. We observed the rotational motion of the nucleus in Caco-2 cells that appears to be driven by actomyosin during the formation of a differentiated confluent epithelium. Single- to multi-cell ring/torus-shaped genomes were observed prior to complex fractal Turing patterns extending from a rotating torus centre in a spiral pattern consistent with a gene morphogen motif. These features may contribute to the well-described differentiation from stem cells at the crypt base to the luminal colon epithelium along the crypt axis. This observation may be useful to study the role of mechanogenomic processes and the underlying molecular mechanisms as determinants of cellular and tissue architecture in space and time, which is the focal point of the 4D nucleome initiative. Mathematical and bioengineer modelling of gene circuits and cell shapes may provide a powerful algorithm that will contribute to future precision medicine relevant to a number of common medical disorders.
Topics: Actomyosin; Caco-2 Cells; Cell Differentiation; Colon; Epithelial Cells; Humans; Intestinal Mucosa; Stem Cells; Tight Junctions
PubMed: 30255651
DOI: 10.1111/jcmm.13853 -
Journal of Morphology Sep 2018Several muroid rodent species are distributed throughout southern Africa. Some species are reportedly classified as opportunistic omnivorous rodents consuming plant,...
Morphometric analysis of the gastrointestinal tract of four African muroid rodent species (Rhabdomys dilectus, Rhabdomys pumilio, Aethomys chrysophilus, and Lemniscomys rosalia).
Several muroid rodent species are distributed throughout southern Africa. Some species are reportedly classified as opportunistic omnivorous rodents consuming plant, seed, and insect material. This study aims to provide a detailed morphometric analysis of the gastrointestinal tract (GIT) of four such omnivorous species, including stomach content analysis. Fixed GIT specimens (n = 5 of each) of Rhabdomys dilectus (Mesic four-striped grass mouse), Rhabdomys pumilio (Xeric four-striped grass mouse), Aethomys chrysophilus (Red rock rat), and Lemniscomys rosalia (Single-striped grass mouse) were weighed. Length and circumference measurements of each anatomically distinct GIT region were determined to calculate the basal surface area (BSA). Histological sections from each GIT region were used to calculate a surface enlargement factor (SEF). The BSA and SEF were multiplied to calculate the luminal surface area (LSA) of each GIT region. Stomach content was analyzed both macroscopically and histologically. All species had a similar GIT morphology, namely a unilocular, hemiglandular stomach with a clear limiting ridge, which indicated the transition from stratified squamous epithelium to glandular epithelium. A large loosely spiralled cecum was present in all species. A narrowing of the cecal apex accompanied by lymph aggregates, confirmed histologically in both Rhabdomys species, indicated a cecal appendix. A single short colonic loop with a unique folding pattern for each species was present in the proximal colon. The colonic mucosal surface presented with proximal V-shaped, and distal longitudinal folds. Intermediate transitional S-shaped folds were present in three species (R. dilectus, R. pumilio, and L. rosalia). Colonic mucosal folds indicated hindgut specialization similar to other muroid rodents. The hindgut specialization was further supported by morphometric analysis, which indicated large BSA and LSA measurements in the cecum and colon. These adaptations are consistent with herbivory, despite stomach content analysis revealing omnivorous tendencies.
Topics: Animals; Cecum; Colon; Gastrointestinal Contents; Gastrointestinal Tract; Rodentia; Stomach
PubMed: 30187940
DOI: 10.1002/jmor.20856 -
Zhongguo Yi Xue Ke Xue Yuan Xue Bao.... Apr 2018Objective To investigate the clinical value of multi-slice spiral CT(MSCT) in the diagnosis of mild digestive tract hemorrhage. Methods Thirty-five patients with mild...
Objective To investigate the clinical value of multi-slice spiral CT(MSCT) in the diagnosis of mild digestive tract hemorrhage. Methods Thirty-five patients with mild gastrointestinal hemorrhage were examined by enhanced MSCT.CT signs were observed and compared with pathologic examination findings.Results Diseases in these 35 patients included gastric and duodenal ulcer and inflammation(n=4,11.4%),esophagogastric variceal rupture(n=7,20.0%),gastric carcinoma(n=3,8.6%),gastric stromal tumor(n=3,8.6%),gastric polyp(n=1,2.9%),colonic malignancy(n=5,14.2%),small intestinal stromal tumor(n=6,17.1%),rectal cancer(n=2,5.7%),intestinal Crohn disease(n=3,8.6%),and jejunum diverticulum combined with hemorrhage(n=1,2.9%).All of them were diagnosed by endoscopy of the digestive tract and confirmed by operation and pathology.The accuracy rate of CT was 100%.The coincidence rate of CT diagnosis was 97.1%.Conclusion MSCT is a promising technique in the localization,qualitative diagnosis,and clinical treatment of mild gastrointestinal hemorrhage.
Topics: Endoscopy; Gastrointestinal Hemorrhage; Humans; Tomography, Spiral Computed
PubMed: 29724301
DOI: 10.3881/j.issn.1000-503X.2018.02.001 -
Endoscopy May 2018Cecal intubation rate represents a key procedural quality parameter in diagnostic colonoscopy. However, even experienced investigators report 10 % of all colonoscopies... (Clinical Trial)
Clinical Trial
BACKGROUND
Cecal intubation rate represents a key procedural quality parameter in diagnostic colonoscopy. However, even experienced investigators report 10 % of all colonoscopies to be difficult and intubation of the cecum is sometimes impossible. A recently developed novel motorized spiral endoscope might potentially overcome some limitations of standard colonoscopy by actively pleating the bowel onto the endoscope. The study aim was to evaluate the feasibility and safety of motorized spiral colonoscopy (MSC) for diagnostic colonoscopy.
METHODS
30 consecutive patients with an indication for diagnostic colonoscopy were enrolled in a proof-of-concept single-center trial.
RESULTS
13 men and 17 women (mean age 68.9 years, range 30 - 90) were enrolled; 43.3 % had diverticula. Mean procedure time was 20.8 min (range 11.4 - 55.3). Cecal intubation rate was 96.7 %. One incomplete colonoscopy occurred because of an unexpected postinflammatory stricture. Adenoma detection rate was 46.6 %. No severe adverse events occurred.
CONCLUSIONS
Results indicate that MSC is safe and effective for diagnostic colonoscopy. It potentially offers advantages in terms of ease and it may facilitate therapeutic interventions.
Topics: Adenoma; Adult; Aged; Aged, 80 and over; Carcinoma; Cecum; Colonic Neoplasms; Colonoscopes; Colonoscopy; Equipment Design; Feasibility Studies; Female; Humans; Male; Middle Aged; Proof of Concept Study
PubMed: 29253918
DOI: 10.1055/s-0043-123577 -
Gan To Kagaku Ryoho. Cancer &... Oct 2017A 72-year-old woman had undergone laparoscope-assisted distal gastrectomy with D1 plus lymph node dissection and antecolic Roux-en-Y reconstruction for early gastric...
A 72-year-old woman had undergone laparoscope-assisted distal gastrectomy with D1 plus lymph node dissection and antecolic Roux-en-Y reconstruction for early gastric cancer. She visited our department outpatient clinic with left upper abdominal pain 1 year and 9 months after the surgery. CT revealed a spiral sign of the superior mesenteric arteriovenous branch. An internal hernia was suspected on hospitalization. Although abdominal symptoms were relieved by conservative treatment, the hernia persisted. Laparoscopic surgery was performed and revealed that almost entire small intestine had been affected due to Petersen's defect. Since no ischemic changes were observed, the defect was repaired laparoscopically with suture closure. There has been no recurrence of internal hernia after the laparoscopic surgery. Internal hernia after distal gastrectomy is relatively rare. However, the risk of internal hernia is high due to the gap between the elevated jejunum and transverse colon mesentery in Roux-en-Y reconstruction and can lead to intestinal necrosis. Since an internal hernia can occur in patients who have undergone gastric resection with Roux-en-Y reconstruction, suture closure of Petersen's defect should be performed to prevent this occurrence.
Topics: Aged; Anastomosis, Roux-en-Y; Female; Gastrectomy; Hernia; Herniorrhaphy; Humans; Intestinal Diseases; Intestine, Small; Laparoscopy
PubMed: 29066700
DOI: No ID Found -
Physics in Medicine and Biology Nov 2017The purpose of this study was to evaluate the dosimetric impact of including the patient table in Monte Carlo CT dose estimates for both spiral scans and scan projection...
The purpose of this study was to evaluate the dosimetric impact of including the patient table in Monte Carlo CT dose estimates for both spiral scans and scan projection radiographs (SPR). CT scan acquisitions were simulated for a Siemens SOMATOM Force scanner (Siemens Healthineers, Forchheim, Germany) with and without a patient table present. An adult male, an adult female and a pediatric female voxelized phantom were simulated. The simulated scans included tube voltages of 80 and 120 kVp. Spiral scans simulated without a patient table resulted in effective doses that were overestimated by approximately 5% compared to the same simulations performed with the patient table present. Doses in selected individual organs (breast, colon, lung, red bone marrow and stomach) were overestimated by up to 8%. Effective doses from SPR acquired with the x-ray tube stationary at 6 o'clock (posterior-anterior) were overestimated by 14-23% when the patient table was not included, with individual organ dose discrepancies (breast, colon, lung red bone marrow and stomach) all exceeding 13%. The reference entrance skin dose to the back were in this situation overestimated by 6-15%. These results highlight the importance of including the patient table in patient dose estimates for such scan situations.
Topics: Adult; Child; Female; Humans; Male; Monte Carlo Method; Phantoms, Imaging; Radiation Dosage; Radiometry; Spine; Tomography, X-Ray Computed
PubMed: 28994662
DOI: 10.1088/1361-6560/aa9259 -
Journal of the Mechanical Behavior of... Jan 2018In the present work, we propose the first structural constitutive model of the passive mechanical behavior of the swine colon that is validated against physiological...
In the present work, we propose the first structural constitutive model of the passive mechanical behavior of the swine colon that is validated against physiological inflation-extension tests, and accounts for residual strains. Sections from the spiral colon and the descending colon were considered to investigate potential regional variability. We found that the proposed constitutive model accurately captures the passive inflation-extension behavior of both regions of the swine colon (coefficient of determination R=0.94±0.02). The model revealed that the circumferential muscle layer does not provide significant mechanical support under passive conditions and the circumferential load is actually carried by the submucosa layer. The stress analysis permitted by the model showed that the colon tissue can distend up to 30% radially without significant increase in the wall stresses suggesting a highly compliant behavior of the tissue. This is in-line with the requirement for the tissue to easily accommodate variable quantities of fecal matter. The analysis also showed that the descending colon is significantly more compliant than the spiral colon, which is relevant to the storage function of the descending colon. Histological analysis showed that the swine colon possesses a four-layer structure similar to the human colon, where the longitudinal muscle layer is organized into bands called taeniae, a typical feature of the human colon. The model and the estimated parameters can be used in a Finite Element framework to conduct simulations with realistic geometry of the swine colon. The resulting computational model will provide a foundation for virtual assessment of safe and effective devices for the treatment of colonic diseases.
Topics: Animals; Biomechanical Phenomena; Colon; Computer Simulation; Elasticity; Finite Element Analysis; Humans; Models, Biological; Muscle, Smooth; Stress, Mechanical; Swine; Tensile Strength
PubMed: 28922650
DOI: 10.1016/j.jmbbm.2017.08.031 -
Journal of the American Veterinary... Sep 2017OBJECTIVE To evaluate the reasons for and outcomes of gastrointestinal tract surgery in pet pigs. DESIGN Retrospective case series. ANIMALS 11 pigs. PROCEDURES The...
OBJECTIVE To evaluate the reasons for and outcomes of gastrointestinal tract surgery in pet pigs. DESIGN Retrospective case series. ANIMALS 11 pigs. PROCEDURES The medical record database of a teaching hospital was searched to identify pet pigs that underwent at least 1 celiotomy because of a possible gastrointestinal tract obstruction between 2004 and 2015. For each pig, information extracted from the medical record included history; signalment; clinical signs; physical examination, diagnostic imaging, and diagnostic test results; perioperative management; surgical diagnosis, duration, and procedures performed; postoperative complications; and outcome. Descriptive data were generated. RESULTS 11 pet pigs underwent 12 celiotomies during the study period. Five pigs with intestinal obstructions caused by foreign bodies survived to hospital discharge. Four pigs were euthanized during surgery: 2 because of extensive adhesions that prevented correction of an intestinal obstruction, 1 because of a perforated spiral colon, and 1 because of neoplasia. One pig with a fecal impaction in the spiral colon died during anesthetic recovery. A diagnosis was not achieved for 1 pig, which was euthanized after surgery because of a deteriorating clinical condition. For the pig that underwent 2 celiotomies, the first procedure was an enterotomy for removal of a foreign body, and the second was an intestinal bypass of a stricture caused by adhesions at the previous enterotomy site. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated prognosis was good for pet pigs following surgical removal of gastrointestinal foreign bodies; however, the presence or development of intra-abdominal adhesions appeared to adversely affect prognosis.
Topics: Animals; Digestive System Surgical Procedures; Female; Gastrointestinal Diseases; Male; Pets; Prognosis; Retrospective Studies; Swine; Swine Diseases; Treatment Outcome
PubMed: 28857699
DOI: 10.2460/javma.251.6.714 -
International Journal of Computer... Nov 2017Automated measurement of the size and shape of colon polyps is one of the challenges in Computed tomography colonography (CTC). The objective of this retrospective study...
PURPOSE
Automated measurement of the size and shape of colon polyps is one of the challenges in Computed tomography colonography (CTC). The objective of this retrospective study was to improve the sensitivity and specificity of smaller polyp measurement in CTC using image processing techniques.
METHODS
A domain knowledge-based method has been implemented with hybrid method of colon segmentation, morphological image processing operators for detecting the colonic structures, and the decision-making system for delineating the smaller polyp-based on a priori knowledge.
RESULTS
The method was applied on 45 CTC dataset. The key finding was that the smaller polyps were accurately measured. In addition to 6-9 mm range, polyps of even <5 mm were also detected. The results were validated qualitatively and quantitatively using both 2D MPR and 3D view. Implementation was done on a high-performance computer with parallel processing. It takes [Formula: see text] min for measuring the smaller polyp in a dataset of 500 CTC images. With this method, [Formula: see text] and [Formula: see text] were achieved.
CONCLUSIONS
The domain-based approach with morphological image processing has given good results. The smaller polyps were measured accurately which helps in making right clinical decisions. Qualitatively and quantitatively the results were acceptable when compared to the ground truth at [Formula: see text].
Topics: Adult; Case-Control Studies; Colon; Colonic Polyps; Colonography, Computed Tomographic; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Multidetector Computed Tomography; Radiographic Image Interpretation, Computer-Assisted; Retrospective Studies; Sensitivity and Specificity; Tomography, Spiral Computed
PubMed: 28573348
DOI: 10.1007/s11548-017-1615-4