Annexin A1, formyl peptide receptor,and NOX1 orchestrate epithelial repair

N-formyl peptide receptors (FPRs) are critical regulators of host defense in phagocytes and are also expressed in epithelia. FPR signaling and function have been extensively studied in phagocytes, yet their functional biology in epithelia is poorly understood. We describe a novel intestinal epithelial FPR signaling pathway that is activated by an endogenous FPR ligand, annexin A1 (ANXA1), and its cleavage product Ac2-26, which mediate activation of ROS by an epithelial NADPH oxidase, NOX1. We show that epithelial cell migration was regulated by this signaling cascade through oxidative inactivation of the regulatory phosphatases PTEN and PTP-PEST, with consequent activation of focal adhesion kinase (FAK) and paxillin. In vivo studies using intestinal epithelial specific Nox1^–/–IEC and AnxA1^–/– mice demonstrated defects in intestinal mucosal wound repair, while systemic administration of ANXA1 promoted wound recovery in a NOX1-dependent fashion. Additionally, increased ANXA1 expression was observed in the intestinal epithelium and infiltrating leukocytes in the mucosa of ulcerative colitis patients compared with normal intestinal mucosa. Our findings delineate a novel epithelial FPR1/NOX1-dependent redox signaling pathway that promotes mucosal wound repair.     

Bioprosthetic heart valves--replacing order with chaos: electron microscopic study

Rheumatic heart disease is a significant clinical entity in young children, especially in the developing world. One of the major long-term effects of ill managed rheumatic fever is irreversible damage to the cardiac valve leaflets, primarily on the left side. With the limited success of currently available mechanical and bioprosthetic valves, there is an urgent need for new directions in bioprosthetic valves, both in material, including source, degree of fixation, surface, bulk modifications, etc., and design. In the present paper, new proposals in the material selection and fabrication of bioprosthetic valves are proposed based on electron microscopic studies of natural valve leaflets and the pericardial surface. Current approaches for bioprosthetic valve fabrications include the wide use of the pericardium as a leaflet material. The present study indicates a need for nondestructive surface examination of pericardial sheets for the elimination of areas of surface voids resulting from gross fiber disorientation. Also, there seems to be a need for incorporation of an in situ fiber renewal mechanism in bioprosthetic leaflets to emulate the natural valve more closely. Apparently natural leaflets have built-in fiber renewal mechanism(s).     

Anterior cruciate ligament injury about 20 years post‐treatment: A kinematic analysis of one‐leg hop

Reduced dynamic knee stability, often evaluated with one‐leg hops (OLHs), is reported after anterior cruciate ligament (ACL) injury. This may lead to long‐standing altered movement patterns, which are less investigated. 3D kinematics during OLH were explored in 70 persons 23 ± 2 years after ACL injury; 33 were treated with physiotherapy in combination with ACL reconstruction (ACL_R) and 37 with physiotherapy alone (ACL_PT). Comparisons were made to 33 matched controls. We analyzed (a) maximal knee joint angles and range of motion (flexion, abduction, rotation); (b) medio‐lateral position of the center of mass (COM) in relation to knee and ankle joint centers, during take‐off and landing phases. Unlike controls, ACL‐injured displayed leg asymmetries: less knee flexion and less internal rotation at take‐off and landing and more lateral COM related to knee and ankle joint of the injured leg at landing. Compared to controls, ACL_R had larger external rotation of the injured leg at landing. ACL_PT showed less knee flexion and larger external rotation at take‐off and landing, and larger knee abduction at Landing. COM was more medial in relation to the knee at take‐off and less laterally placed relative to the ankle at landing. ACL injury results in long‐term kinematic alterations during OLH, which are less evident for ACL_R.     

Umbilical Negative Pressure Dressing for Transumbilical Appendectomy in Childern

Methods:This study was a retrospective chart review of 1377 patients (2–20 years) undergoing laparoscopic appendectomy for acute appendicitis in 2 tertiary care referral centers from January 2007 through December 2012. Twenty-two different operative technique/dressing variations were documented. The 6 technique/dressing groups with >50 patients were assessed, including a total of 1283 patients.Results:The surgical site infection rate of the 220 patients treated with TULAA and application of an umbilical vacuum dressing with dry gauze is 1.8% (95% CI, 0.0–10.3%). This compares to an infection rate of 4.1% (95% CI, 1.3–10.5%) in 97 patients with dry dressing without vacuum. In the 395 patients who received an umbilical vacuum dressing with gauze and bacitracin, the surgical site infection rate was found to be 4.3% (95% CI, 2.7–6.8%).Conclusions:Application of an umbilical negative-pressure dressing with dry gauze lowers the rate of umbilical site infections in patients undergoing transumbilical laparoscopic-assisted appendectomy for acute appendicitis.     

Internal fixation and muscle pedicle bone grafting in femoral neck fractures

Background:

The treatment of displaced intracapsular femoral neck fracture is still an unsolved problem. Non-union and avascular necrosis are the two main complications of this fracture, especially if patient presents late. Muscle pedicle bone grafting has been advocated to provide additional blood supply. We present analysis of our 32 cases of displaced femoral neck fracture treated by internal fixation and quadratus femoris based muscle pedicle bone grafting.

Materials and Methods:

Open reduction and internal fixation with muscle pedicle grafting was done in 32 patients. The age of patients varied from 14-62 years (average age 45 years) with male to female ratio of 13:3. Twenty-nine fractures were more than three weeks old. All the cases were treated by Meyers'' procedure. The fracture was internally fixed after open reduction and then a muscle pedicle graft was applied. It was supplemented by cancellous bone graft in seven cases. Fixation was done by parallel cancellous lag screws (n = 19), crossed Garden''s screws (n = 7), parallel Asnis screws (n = 5) and Moore''s pin (n = 1).Quadratus femoris muscle pedicle graft was used in 32 cases. In the initial 12 cases the graft was fixed with circumferential proline sutures, but later, to provide a secure fixation, the graft was fixed with a cancellous screw (n = 20). Postoperative full weight bearing was deferred to an average of 10 weeks.

Results:

Union was achieved in 26/29 (89.65%) cases which could be followed for an average period of 3.4 years, (2-8.5 years) with good functional results and had the ability to squat and sit cross-legged. Results were based on hip rating system given by Salvatti and Wilson. The results were excellent in 15 cases, good in four cases, fair in four cases and poor in six cases. Complications were avascular necrosis (n = 2), transient foot drop (n = 2), coxa-vara (n = 1) and temporary loss of scrotal sensation (n = 1).

Conclusion:

Muscle pedicle bone grafting with internal fixation is a viable treatment option in displaced femoral neck fractures with late presentation.     

Comparison of Functional Outcomes,Femoral Rollback and Sagittal Stability of Anterior-Stabilized Versus Posterior-Stabilized Total Knee Arthroplasty: A Systematic Review and Meta-analysis of Randomized Controlled Trials

PurposeTotal knee arthroplasty (TKA) has improved leaps and bounds in terms of design to improve clinical outcomes and achieve better rehabilitation of the patients. Ultra-congruent inserts (UC) were designed to replace the need for posterior stabilized (PS) implants. The purpose of this review was to evaluate clinical outcomes, femoral rollback, functional scores, range of motion, sagittal laxity, complication rates, and isokinetic performance between UC and PS TKA among RCTsMethodsElectronic databases such as PubMed, Scopus, opengrey, and Cochrane were searched from date of inception up to mid-April 2021, and meta-analysis was performed following PRISMA guidelines. This study analyzed outcomes, femoral rollback, tibial sagittal laxity and isokinetic performance.ResultsTen RCTs identified 852 knees, of which 420 underwent UC TKAs and 432 underwent PS TKA. Compared to UC TKA, a significantly better sagittal stability (p = 0.17) and femoral rollback (p < 0.00001) in PS TKAs was noted, although no statistically significant difference was found in the assessment of the range of motion (p = 0.19) and functional scores. Both the groups had similar isokinetic performance with extensor torque (p = 0.97) and flexor torque (p = 0.37).ConclusionsWe conclude with the current meta-analysis that there are no added benefits for UC over PS inserts and these inserts have a higher sagittal laxity and less femoral roll back in cruciate sacrificing UC knee. But since there are no long-term wear data, UC inserts with CS technique should be used cautiously and may be used only when the PCL cannot be balanced adequately. There is no evidence or only a few to support the superiority of the AS TKA in terms of clinical outcomes or isokinetic performance or femoral external rotation over PS TKA.Level of EvidenceLevel I, Systematic review and meta-analysis of RCTs.     

An echo-cardiographic (M-mode & 2D) analysis of thalassaemia major

25 cases of thalassaemia major were studied by 2D and M-mode echocardiography. A significantly increased (p less than 0.001) mean value (100.8 +/- 27.37 msec, range 80 to 140 msec) of A2-E (early relaxation period) interval on M-mode was observed in thalassemia in comparison to mean level (82.6 +/- 5.7, range 60 to 100 msec) of control population. No significant differences were noted in FS % (fractional shortening) and EF% (ejection fraction) when compared to corresponding normal values respectively. Mean serum iron concentration (142.2 +/- 29.1 micrograms/dl, range 102 to 192 micrograms/dl) was significantly higher in thalassaemia as compared to normal population (mean 106.3 +/- 11.4 micrograms/dl, range 75 to 120 micrograms/dl). There was also a direct correlation between serum iron concentration and A2-E interval. 11 patients (44%) showed abnormal A2-E interval but only 3 patients (12%) showed abnormal percentage of FS and EF. It is therefore concluded that A2-E interval will help to detect early left ventricular dysfunction much before overt and irreversible heart failure becomes manifest and which will also help to optimise transfusion and chelation therapy.