Although the osteolysis of the coracoid graft is frequently observed after the Latarjet procedure particularly in its proximal part, its pathomechanism is not well understood.
Three-dimensional ...finite element glenohumeral joint models were developed using CT-DICOM data of 10 normal shoulders. A 25% bony defect was created on the anterior glenoid rim, and the coracoid process was transferred flush with the glenoid cartilage using 2 half-threaded screws. In the hanging arm as well as in the 90° abducted positions, a compressive load (50 N) was applied to the greater tuberosity toward the center of the glenoid and a tensile force (20 N) was applied to the coracoid tip along the direction of the conjoint tendon. Next, elastic analysis was performed, and the distribution patterns of the equivalent stress as well as the maximum principal stress were compared among 4 parts (proximal/distal and medial/lateral) of the coracoid graft.
Both the equivalent stress and the maximum principal stress were reduced in the proximal half of the coracoid graft. A high stress concentration was observed in the lateral aspect of the coracoid graft particularly in the 90° abducted position. The proximal-medial part demonstrated the lowest equivalent stress as well as the maximum principal stress for both arm positions, which were significantly lower than those in the distal 2 parts.
In the Latarjet procedure, the proximal-medial part of the coracoid graft demonstrated the most evident stress shielding, which may play an important role in postoperative osteolysis.
Background
Capsule endoscopy can be used to identify the early stage of small bowel Crohn’s disease (CD). We evaluated significant small bowel capsule endoscopy (SBCE) findings that can lead to early ...diagnosis of CD.
Methods
We retrospectively accumulated clinical and SBCE data of 108 patients (63 with and 45 without CD). Types of small bowel mucosal injuries, including erosion, ulceration, and cobblestone appearance, and the alignment of diminutive lesions were compared between patients with and without CD. Inter- and intra-observer agreement in the determination of lesions was assessed in 25 pairs of SBCE from the two groups.
Results
Under SBCE, cobblestone appearance (33% vs. 2%,
p
< 0.0001), longitudinal ulcers (78% vs. 20%,
p
< 0.0001), and irregular ulcers (84% vs. 60%,
p
< 0.01) were more frequently found in patients with CD. Linear erosion (90% vs. 38%,
p
< 0.0001) and irregular erosion (89% vs. 64%,
p
< 0.005) were also more frequent in patients with CD. Furthermore, circumferential (75% vs. 9%,
p
< 0.0001) and longitudinal (56% vs. 7%,
p
< 0.0001) alignment of diminutive lesions, mainly observed in the 1st tertile of the small bowel, was more frequent in patients with CD. Good intra-observer agreement was found for ulcers, cobblestone appearance, and lesion alignment. However, inter-observer agreement of SBCE findings differed among observers.
Conclusions
Circumferential or longitudinal alignment of diminutive lesions, especially in the upper small bowel, may be a diagnostic clue for CD under SBCE, while inter-observer variations should be cautiously considered when using SBCE.
Although a few reports of neuroendocrine tumor (NET) in the stomach or appendix with surrounding micronests have been published, cases of rectal NET are rare. We herein report a unique case of a ...patient with single rectal NET treated endoscopically. A pathological examination revealed multiple endocrine cell micronests (ECMs) in the submucosal layer around the main NET lesion. Neither lymph node metastasis nor distant metastasis in computed tomography was observed six years after the treatment. Because case reports of multiple ECM are very rare, the significance of malignancy is unclear. It therefore appears to be necessary to accumulate similar cases.
Acquired mutations of JAK2 and TET2 are frequent in myeloproliferative neoplasms (MPNs). We examined the individual and cooperative effects of these mutations on MPN development. Recipients of ...JAK2V617F cells developed primary myelofibrosis–like features; the addition of loss of TET2 worsened this JAK2V617F-induced disease, causing prolonged leukocytosis, splenomegaly, extramedullary hematopoiesis, and modestly shorter survival. Double-mutant (JAK2V617F plus loss of TET2) myeloid cells were more likely to be in a proliferative state than JAK2V617F single-mutant myeloid cells. In a serial competitive transplantation assay, JAK2V617F cells resulted in decreased chimerism in the second recipients, which did not develop MPNs. In marked contrast, cooperation between JAK2V617F and loss of TET2 developed and maintained MPNs in the second recipients by compensating for impaired hematopoietic stem cell (HSC) functioning. In-vitro sequential colony formation assays also supported the observation that JAK2V617F did not maintain HSC functioning over the long-term, but concurrent loss of TET2 mutation restored it. Transcriptional profiling revealed that loss of TET2 affected the expression of many HSC signature genes. We conclude that loss of TET2 has two different roles in MPNs: disease accelerator and disease initiator and sustainer in combination with JAK2V617F.
•Loss of TET2 accelerates the degree of malignancy of MPNs in combination with JAK2V617F.•Loss of TET2 sustains MPNs in combination with JAK2V617F.
Pullout of inserted anchor constitutes one of the pathomechanisms of re-tearing after rotator cuff repair. The purpose of the present study was to investigate the fixation properties of suture ...anchors using 3-dimensional finite element method.
The computer models of three types of anchors (TwinFix Ti, HEALICOIL PK and HEALICOIL RG) were inserted into the isotropic cube model that simulated cancellous bone. In the virtual pullout testing, a tensile load (500 N) along the long axis of the inserted anchor was applied to the site of suture thread attachment to simulate a traction force. The distribution of von Mises equivalent stress, the failure patterns of elements inside the cube and the anchor displacement were compared among the three anchors.
In TwinFix Ti, the highest stress concentration was seen around the anchor threads close to the surface of the cube, which caused element failure at this site. On the other hand, both HEALICOIL PK and HEALICOIL RG demonstrated a high stress concentration as well as element failure around the anchor tip. Comparing the anchor displacement, HEALICOIL RG showed the smallest displacement among the three anchors. The tensile loads that required a 0.1-mm displacement for TwinFix Ti, HEALICOIL PK and HEALICOIL RG were 400 N, 370 N, and greater than 500 N, respectively.
The bony structures close to the footprint surface may be damaged during surgery due to preparation for the bony bed as well as the insertion of anchors. Thus, we assumed that HEALICOIL RG represented the best initial fixation properties among the three anchors tested. Virtual pullout testing using 3-dimensional finite element method could reveal the detailed biomechanical characteristics of each suture anchor, which would be important for shoulder surgeons to improve the clinical outcomes of rotator cuff repair.
Retearing mechanism after transosseous equivalent (TOE) rotator cuff repair has not been fully clarified yet.
The purposes of this study were to compare the stress distribution pattern in the tendon ...stump between knotted and knotless TOE repair and to investigate the role of suture tension applied during medial knot tying using a 3-dimensional finite element (3D-FE) method.
Both knotted and knotless TOE repairs were simulated on the 3D-FE human rotator cuff tear model. Elastic analysis was performed to compare the stress distribution pattern inside the tendon between the two models. The amount of compressive load applied to the medial-row sutures was then changed as 0, 20, 40, 60, 80, and 100 N in the knotted model.
Knotted model demonstrated more distinct stress concentration inside the tendon around medial-row sutures than the knotless model. Mean von Mises equivalent stress in this area in the 0, 20, 40, 60, 80, and 100 N models was 0.26, 0.35, 0.50, 0.70, 1.11, and 1.14 MPa, respectively.
In the knotted TOE repair, tight medial knot tying might cause a high stress concentration around medial knots, which may constitute one of the pathogenetic factors of postoperative retearing at this site.
TET2 mutation in diffuse large B-cell lymphoma Kubuki, Yoko; Yamaji, Takumi; Hidaka, Tomonori ...
Journal of Clinical and Experimental Hematopathology,
2017, Volume:
56, Issue:
3
Journal Article
Peer reviewed
Open access
Ten-eleven translocation-2 (TET2) mutation is frequently observed in myeloid malignancies, and loss-of-function of TET2 is essential for the initiation of malignant hematopoiesis. TET2 mutation ...presents across disease entities and was reported in lymphoid malignancies. We investigated TET2 mutations in 27 diffuse large B-cell lymphoma (DLBCL) patients and found a frameshift mutation in 1 case (3.7%). TET2 mutation occurred in some populations of DLBCL patients and was likely involved in the pathogenesis of their malignancies.
Background
Various noninvasive tests have been studied to screen for patients with Crohn’s disease (CD), and were found to have limited accuracy and sensitivity, particularly in Asian populations. ...The aim of our study was to explore the possible diagnostic utility of antibodies to the CD peptide (ACP) in patients with CD.
Methods
In a multicenter study using enzyme-linked immunosorbent assay, serum ACP levels were determined in 196 patients with CD, 210 with ulcerative colitis, 98 with other intestinal diseases, 132 with other inflammatory diseases, and 183 healthy controls. and then examined for correlation to clinical variables. The diagnostic utility of ACP was evaluated by receiver operating characteristics analysis and compared with anti-
Saccharomyces
cerevisiae
antibodies (ASCA).
Results
ACP levels were significantly elevated in the CD patients, but not in the other groups that included UC, other intestinal diseases, other inflammatory diseases and the healthy controls. Among these other groups, ACP levels were not significantly different. In the CD patients, ACP had a higher sensitivity and specificity (63.3 and 91.0 %, respectively) than ASCA (47.4 and 90.4 %). ACP levels were negatively associated with disease duration, but not with CDAI, disease location, or medical treatment.
Conclusions
ACP, a newly proposed serologic marker, was significantly associated with CD and was highly diagnostic. Further investigation is needed across multiple populations of patients and ethnic groups, and more importantly, in prospective studies.
A 37-year-old man underwent thymectomy for myasthenia gravis and subsequently received oral medication. Screening upper gastrointestinal endoscopy revealed a 20mm fading concave lesion on the ...posterior wall of the greater curvature of the stomach. He was diagnosed with signet-ring cell carcinoma based on histopathological examination of a biopsy specimen and was referred to our hospital for further management. Preoperative evaluation led to a diagnosis of early gastric cancer and he was scheduled for endoscopic submucosal dissection (ESD). Benzodiazepines are contraindicated for sedation in patients with myasthenia gravis, and a drug that does not cause muscle relaxation should be administered. Therefore, in this patient, we performed successful ESD using a combination of dexmedetomidine, pentazocine, and hydroxyzine for sedation. Dexmedetomidine is useful for limited sedation that is required during endoscopic procedures in patients with myasthenia gravis.
TET2 Mutation in Adult T-Cell Leukemia/Lymphoma Shimoda, Kazuya; Shide, Kotaro; Kameda, Takuro ...
Journal of Clinical and Experimental Hematopathology,
2015, Volume:
55, Issue:
3
Journal Article
Peer reviewed
Open access
Loss-of-function of ten-eleven translocation-2 (TET2) is a common event in myeloid malignancies, and plays pleiotropic roles, including augmenting stem cell self-renewal and skewing hematopoietic ...cells to the myeloid lineage. TET2 mutation has also been reported in lymphoid malignancies; 5.7～12% of diffuse large B-cell lymphomas and 18～83% of angioimmunoblastic T-cell lymphomas had TET2 mutations. We investigated TET2 mutations in 22 adult T-cell leukemia/lymphoma (ATLL) patients and identified a missense mutation in 3 cases (14%). TET2 mutation occurred in a number of ATLL patients and was likely involved in their leukemogenesis. J Clin Exp Hematop 55(3) : 145-149, 2015
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