Hamstring graft tibial fixation: biomechanical properties of different linkage systems

This biomechanical study analyzed the mechanical properties of different linkage systems commonly used in hamstring tendon ACL reconstruction. Two kinds of tapes, 5-mm braided polyester (Mersilene) and 3-mm woven polyester (Orthotape), were connected to a particular staple in bovine bone sections in single- and double-loop constructs with five replicates of each. These constructs underwent straight pull tensile tests, residual tensile tests, and fatigue tests at a loading regime of 540,000 cycles at 25 Hz frequency, using an Instron tensile test machine. Protrusion heights of the constructs were measured. The double-loop Mersilene-Fastlok construct was weaker than either single-loop or double-loop Orthotape-Fastlok construct. The mean failure strength of double-loop Orthotape-Fastlok was 93% higher and its mean stiffness was 40% greater at failure than that of Mersilene-Fastlok. At a 150-N load Mersilene-Fastlok was stiffer, while at 300 N Orthotape-Fastlok was stiffer. The thickness of Orthotape-Fastlok resulted in 1 mm more device protrusion. In hamstring tendon ACL reconstructions with indirect fixation we advocate the use of woven polyester (Orthotape) with Fastlok as a linkage material over braided polyester (Mersilene) with Fastlok because of its superior strength and stiffness.     

Intestinal uptake of nutrients in normal and malnourished animals infected with Giardia lamblia

The effect of malnutrition on the uptake of nutrients was studied in Swiss albino mice infected with Giardia lamblia. The moderate deficiency (8% protein-deficient diet) was observed to enhance the uptake of nutrients like glucose and alanine, whereas in severely malnourished (3% protein-deficient diet) animals the uptake was significantly decreased (p less than 0.001). G. lamblia infection in mice decreased the uptake of nutrients and this recovered slightly with the recovery of infection. The combined effect of moderate protein deficiency and infection lowered the enhanced uptake observed in moderately malnourished animals to a significant level (p less than 0.001). In severely malnourished animals, infection with G. lamblia showed further deleterious effects on the uptake of nutrients.     

Characteristics of HER2-positive breast cancer diagnosed following the introduction of universal HER2 testing

The aim of this study was to determine the impact of universal HER2 testing on the clinico-pathologic profile of HER2+ breast cancer. Data were extracted from breast cancer pathology reports spanning two periods: before (2003/4, n = 379), and after (2008/9, n = 560) the introduction of universal testing. In 2003/4, 43.3% of breast cancers were tested for HER2 with 16% of tested cases HER2+. In 2008/9, 98.4% of cases were tested with 14.7% HER2+. In 2008/9, HER2+ status was associated with younger age, higher grade, increased tumour size, lymph node involvement, negative oestrogen and/or progesterone receptor status. HER2+ cases diagnosed in 2003/4 were not significantly different in respect of these features. The rate of HER2+ breast cancer amongst screen detected cases in 2008/9 was 8.3%. The phenotype of HER2+ breast cancer was stable following the introduction of universal testing. The overall rate of HER2+ breast cancer was influenced by screen detection.     

Fundal tube esophagoplasty for esophageal reconstruction in atresia

Purpose: This is a report of 4 patients with long gap/pure esophageal atresia, who, after an initial gastrostomy and cervical esophagostomy at birth, were treated with a new technique called fundal tube esophagoplasty.Methods: The technique consisted of mobilization of the distal esophageal stump, division of the left gastric artery, and mobilization of upper half of stomach. Both walls of the stomach were incised in the region of the fundus starting on the lesser curvature in such a way that a tube was created out of the fundus, and the native esophageal stump appears to be an extension of this neoesophagus. This neoesophagus was brought to the neck by the retrosternal route and in a second stage, esophago-esophageal anastomosis was made. Thal’s fundoplication was added in 2 cases.Results: All the stages have been completed successfully in 4 babies. They have been followed up for periods ranging from 8 to 24 months after restoration of esophageal continuity. All the children are thriving.Conclusions: Fundal tube esophagoplasty (1) serves to provide a neoesophagus of natural caliber, (2) utilizes native esophagus in reconstruction, (3) does not produce a space-occupying problem in the mediastinum, and (4) preserves the gastric reservoir function. In this early experience, it appears to fulfill all the requirements of a good esophageal substitute.     

CD4+CD25+ regulatory T cells protect against injury in an innate murine model of chronic kidney disease

Studies of mechanisms of disease regulation by CD4+CD25+ regulatory T cells (Treg) have been focused on their interaction with effector T cells; however, the possibility that regulation might involve noncognate cells has not been explored in detail. This study investigated the effect of CD4+CD25+ Treg on macrophage proinflammatory properties and phenotype in vitro and found that they modulate macrophages by inhibiting their activation, leading to reduced proinflammatory cytokine production and a downregulated effector phenotype. For testing the in vivo significance of this effect, CD4+CD25+ T cells that expressed high levels of Foxp3 were reconstituted into SCID mice after induction of Adriamycin nephropathy, a noncognate model of chronic renal disease. CD4+CD25+ T cells significantly reduced glomerular and interstitial injury. In addition, there was a significant fall in the number of macrophages in both the glomeruli and interstitium of SCID mice that were reconstituted with Treg as compared with the Adriamycin alone group. Blockade of TGF-beta using neutralizing antibodies significantly impaired the protective effect of Treg. These findings delineate a TGF-beta-dependent Treg-macrophage inhibitory interaction that can explain cognate-independent protection by Treg.     

Computer Navigation Helps Reduce the Incidence of Noise After Ceramic-on-Ceramic Total Hip Arthroplasty

Background

Noise after ceramic-on-ceramic (CoC) total hip arthroplasty (THA) is a well-recognized problem. Computer navigation has been shown to achieve desired implant orientation. Our aim was (1) to compare the incidence of noise between navigated and conventional CoC THAs and (2) to determine the factors associated with noise.

Cerebral haemodynamics in patients with chronic renal failure: effects of haemodialysis

Background. We measured middle cerebral artery (MCA) flow velocity(FV), dynamic pressure autoregulation, and carbon dioxide reactivity(CRCO₂) in patients with chronic renal failure before and afterhaemodialysis using transcranial Doppler ultrasonography. Methods. Twelve patients on long-term haemodialysis were recruited.MCA FV was measured continuously. The transient hyperaemic responsetest was used to assess cerebral autoregulation, and per centchange in FV per kPa change in end-tidal carbon dioxide wascalculated to assess CRCO₂. All measurements were recorded beforeand after haemodialysis. Results. MCA FV (mean [SD]) decreased from 57 (10) cm s^–1before to 46 (13) cm s^–1 after haemodialysis (P<0.01).The transient hyperaemic response ratio (THRR) was (mean [SD])1.29 (0.13) before haemodialysis and did not change significantlyfollowing haemodialysis (1.36 [0.10]). CRCO₂ was 21.7 (8.3)%kPa^–1 before haemodialysis and remained unchanged afterwards(20.9 [3.8]% kPa^–1). Values in normal subjects for MCAFV, THRR and CRCO₂ are 56 (12) cm s^–1, 1.26 (0.13) and22 (6)% kPa^–1, respectively. Conclusions. MCA FV decreases significantly after haemodialysis.Dynamic pressure autoregulation and CRCO₂ remain normal in patientswith chronic renal failure, and are not altered significantlyby haemodialysis. Presented at the European Society of Anaesthesiologists AnnualCongress Amsterdam, May 1999.     

Effects of stellate ganglion block on cerebral haemodynamics as assessed by transcranial Doppler ultrasonography

Background. Stellate ganglion block (SGB) causes vasodilatationin the skin of the head and neck because of regional sympatheticblock. Its effects on cerebral haemodynamics, in health or indisease, are not clear. We evaluated the effects of SGB on ipsilateralmiddle cerebral artery flow velocity (MCAFV), estimated cerebralperfusion pressure (eCPP), zero flow pressure (ZFP), carbondioxide reactivity (CO₂R) and cerebral autoregulation usingtranscranial Doppler ultrasonography (TCD). Methods. Twenty male patients, with pre-existing brachial plexusinjury, and undergoing SGB for the treatment of complex regionalpain syndrome of the upper limb, were studied. For SGB, 10 mlof plain lidocaine 2% was used and the onset of block was confirmedby presence of ipsilateral Horner's syndrome. The MCAFV, eCPP,ZFP, CO₂R, and cerebral autoregulation were assessed beforeand after SGB using established TCD methods. The changes inthese variables were analysed using Wilcoxon's signed rank test. Results. The block caused a significant decrease in MCAFV frommedian (inter-quartile range) value of 61 (53, 67) to 55 (46,60) cm s^–1, a significant increase in eCPP from 59 (51,67) to 70 (60, 78) mm Hg, and a significant decrease in ZFPfrom 32 (26, 39) to 25 (16, 30) mm Hg. There were no significantchanges in CO₂R or cerebral autoregulation. Conclusion. The increase in eCPP, decrease in ZFP, and no changesin CO₂R or cerebral autoregulation suggest that the SGB decreasescerebral vascular tone without affecting the capacity of thevessels to autoregulate. These effects may be of therapeuticadvantage in relieving cerebral vasospasm in certain clinicalsettings.     

Renal allograft tuberculosis: report of three cases and review of literature

Renal transplant recipients are prone to a variety of infections due a persistent immunodepleted state. Incidence of tuberculosis in this population is much higher compared with the general population. While pulmonary tuberculosis still remains the commonest form in this population, renal allograft tuberculosis is very rare. We report two cases of isolated allograft tuberculosis and one case of allograft tuberculosis with coexistent pleuro-pulmonary and bone marrow involvement. All three cases had presented with pyrexia of unknown origin, wherein despite extensive investigations the cause was not found. In two cases the diagnosis was confirmed on histology. Two cases responded to non-rifampicin-based modified antitubercular treatment and one to conventional four-drug Rifampicin-based regimen. Graft function improved in two cases while in one case the graft was lost. Tuberculosis involving the renal allograft is a potential cause for graft dysfunction/loss and requires a high index of suspicion for diagnosis. Timely detection and early institution of therapy can help save the renal allograft.