Age influences the efficacy of osteochondral autograft transfer: Promising results for patients under 40

BACKGROUND

Previous research using osteochondral autograft transfer (OAT) has shown poorer outcomes with increasing patient age. The aim of this article is to evaluate a cohort of patients that received an OAT and to correlate their clinical results with their age at procedure.

METHODS

Patients that underwent an OAT to treat an osteochondral (OC) lesion with a minimum 24-month follow-up were included. Patients were categorized into two groups based on their age at procedure (<40 years and ≥40 years). Postoperatively, each patient completed the Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), and Lysholm scales.

RESULTS

51 patients were included (35<40 years, 16≥40 years). Mean follow-up was 4.2 years (2-7). For patients<40 years, IKDC averaged 80.8 (SD 15.9) versus 71.2 (SD 19.4) in ≥40 years (p=0.03). For patients <40 years, Lysholm averaged 85.9 (SD 10.8) versus 77.0 (SD 21.6) in ≥40 years (p=0.02). For patients<40 years, KOOS averaged 78.3 (SD 11.8) versus 68.9 (SD 18.5) in ≥40 years (p=0.01). There was a 100% sensibility in identifying all the patients with a poor IKDC and Lysholm from 34 years old (AUC 0.76 and 0.8).

CONCLUSIONS

OAT has better outcomes in patients younger than 40 years compared to patients older than 40 years. Based on the prognostic capacity of age, the ideal candidate for an OAT is a patient younger than 34 years old.

Histological validation of cardiac 99mTc-DPD uptake in patients with cardiac transthyretin amyloidosis

Background

Cardiac transthyretin (ATTR) amyloidosis is a progressive and fatal disease caused by the extracellular deposition of misfolded ATTR protein in the myocardium. In an era where new therapies are rapidly emerging, development of non-invasive imaging modalities to quantify amyloid burden over time is of utmost importance. Although endomyocardial biopsy (EMB) remains the gold standard in amyloid detection and typing, 99mTc-DPD scintigraphy is a widely available and accurate tool for non-invasive diagnosis of cardiac ATTR amyloidosis. However, it remains to be determined whether the degree of cardiac 99mTc-DPD uptake correlates with the histological amyloid infiltration on EMB – thus, justifying 99mTc-DPD scintigraphy as a disease monitoring tool.

Aim

This single-centre observational study aimed to compare the extent of histologic amyloid burden on EMB with the quantification of cardiac 99mTc-DPD uptake on scintigraphic planar images and SPECT/CT acquisitions in cardiac ATTR amyloidosis.

Methods

26 patients with cardiac ATTR amyloidosis were enrolled. Patients were included in case of (1) EMB-proven ATTR amyloidosis and (2) availability of 99mTc-DPD scintigraphy (reference activity: 550 MBq). Visual interpretation using the Perugini score, quantitative analysis of cardiac 99mTc-DPD uptake by planar whole-body imaging and SPECT/CT using regions of interest (ROI) were performed, and heart to whole-body ratio (H/WB) was measured. Histological amyloid load was quantified as percentage of the analysed myocardial tissue using Sulfated Alcyan Blue staining and the Fiji-ImageJ programme. Pearson's and Spearman's correlation were used for correlation analysis and assessment of agreement.

Results

ATTR patients had a median age of 77 [73–79] years and were predominantly male (85%). An abnormal Perugini score (i.e. 2 or 3) was present in 25 patients (96%), whereas 1 patient was assigned Perugini score 1 (4%). Increased cardiac tracer uptake was documented in all patients, both on 99mTc-DPD planar scintigraphy (ROImean 129±37) and SPECT/CT (ROImean 369±142). Histologic amyloid burden on EMB was 32±19% on average. It significantly correlated with Perugini score (r=0.56 p=0.003), as well as with cardiac 99mTc-DPD uptake (planar: r=0.54 p=0.006, SPECT/CT: r=0.48 p=0.018) and H/WB (r=0.41 p=0.046).

Conclusion

We have demonstrated a good correlation between histological amyloid infiltration on EMB and cardiac 99mTc-DPD uptake on scintigraphic planar images and SPECT/CT scans, illustrating the potential of 99mTc-DPD scintigraphy to yield reliable quantitative information on cardiac amyloid burden. Further investigations with a larger number of patients are needed to confirm our findings and to implement thresholds in cardiac 99mTc-DPD uptake for being used for guiding disease and therapy management.

Funding Acknowledgement

Type of funding sources: None.

Somatic and prejunctional nicotinic receptors in cultured rat sympathetic neurones show different agonist profiles

1. The release of [3H]-noradrenaline ([3H]-NA) in response to nicotinic acetylcholine receptor (nAChR) agonists was compared with agonist-induced currents in cultured rat superior cervical ganglion (SCG) neurones. 2. [3H]-NA release in response to high concentrations of nicotinic agonists was reduced, but not fully inhibited, by the presence of either tetrodotoxin (TTX) or Cd2+ to block voltage-gated Na+ or Ca2+ channels, respectively. We used the component of transmitter release that remained in the presence of these substances (named TTX- or Cd2+-insensitive release) to pharmacologically characterize nAChRs in proximity to the sites of vesicular exocytosis (prejunctional receptors). Prejunctional nAChRs were activated by nicotinic agonists with a rank order of potency of dimethylphenylpiperazinium iodide (DMPP) > nicotine > cytisine > ACh, and with EC50 values ranging from 22 microM (DMPP) to 110 microM (ACh). 3. [3H]-NA release in response to low concentrations of nAChR agonists was fully inhibited by the presence of either TTX or Cd2+ (named TTX- or Cd2+-sensitive release). TTX-sensitive release was triggered by nicotinic agonists with a rank order of potency of DMPP > cytisine approximately nicotine approximately ACh, which due to its similarity to TTX-insensitive release indicates that it might also be triggered by prejunctional-type nAChRs. The EC50 values for TTX (Cd2+)-sensitive release were less than 10 microM for all four agonists. 4. By contrast to transmitter release, somatic nAChRs as seen by patch clamp recordings were most potently activated by cytisine, with a rank order of potency of cytisine > nicotine approximately DMPP > ACh. EC50 values for the induction of currents exceeded 20 microM for all four agonists. 5. The nicotinic antagonist mecamylamine potently inhibited all transmitter release in response to nicotine. alpha-Bungarotoxin (alpha-BuTX) was, on the other hand, without significant effect on nicotine-induced TTX-insensitive release. The competitive antagonist dihydro-beta-erythroidine (DHbetaE) caused rightward shifts of the dose-response curves for both TTX-sensitive and TTX-insensitive transmitter release as well as for currents in response to nicotine, with pA2 values ranging from 4.03 to 4.58. 6. Due to clear differences in the pharmacology of agonists we propose that nAChRs of distinct subunit composition are differentially targeted to somatic or axonal domains.

Morphology and blood supply of the iliac crest applied to jaw reconstruction

The aim of this study was to improve vessel and nerve security and the harvesting procedure of the iliac crest in the microvascular reconstruction of the upper and lower jaw by iliac crest flap in cases of tumour invasion or trauma. The critical points for the surgeon in harvesting the iliac crest are the course of the deep circumflex iliac artery and lateral cutaneous nerve of the thigh in relation to the iliac crest and the position of their subsequent ramifications. Bilateral anatomical preparations of the iliac bone (total 90 dissections) were examined in 45 formalin preserved cadavers (21 male, 24 female) with the course of the vessel and nerve supply being mapped. Topographic variations of muscles, bones, vessels and nerves were documented by measurement by photographic documentation and diagrams. In 78% (70 cases) a standard-type arrangement with a single main vessel coming from the external iliac artery above the inguinal ligament and crossing the upper part of the iliac crest with second ramifications was observed. In 12% (11 cases) the main vessel was observed to be 2-3 cm below the iliac crest, in 7% (6 cases) a second main branch of the deep circumflex iliac artery was found to run parallel to the iliac crest. In other cases the following variations were observed: one main vessel without ramification, separate branching of the main vessel and ramifications or common trunks of the deep and superficial circumflex iliac arteries. Because of these results it might be possible to perform window resection of the iliac crest in some cases rather than bloc resection: this may have postoperative advantages for the patient.

A pig collagen peptide fraction. A unique material for maintaining biological activity during lyophilization and during storage in the liquid state

There is frequent use of human and animal proteins as stabilizers during lyophilization of a variety of biological substances with a view to long term stable storage. This report describes the comparative excellent stabilizing effect of a porcine collagen peptide fraction (CPF) during the lyophilization and subsequent storage of three commonly used biological substances, alkaline phosphatase, tissue plasminogen activator and thrombin. The CPF was heated to 150 degrees C for one hour before use. The CPF was shown to have some advantage during lyophilized storage over human serum albumin. Solutions of thrombin stored in CPF at room temperature and at 37 degrees C for one week retained nearly all activity, while storage of thrombin in human serum albumin solution at 37 degrees C lost nearly all biological activity. These preliminary data suggest that porcine CPF is a safe and advantageous stabilizer for addition to biological products with a view to long-term lyophilized storage and short-term liquid storage.

Streptococcus milleri as a cause of antecubital abscess and bacteremia in intravenous drug abusers

S milleri should be added to the list of organisms producing wound infections in parenteral drug addicts. Recovery of "viridans streptococci" from an antecubital aspirate should prompt the clinician to request speciation, examine closely for abscess formation, and anticipate prolonged antibiotic therapy.

Simple technique for shaping hydrophilically coated guide wires: usefulness in selective angiography

A method is described to shape hydrophilically coated guide wires with specially prepared electronic round-nose pliers. These shaped wires can be engaged with 4-F catheters in the performance of selective angiography. Now even demanding selective catheterizations may be accomplished more easily and safely with small catheters.