Human NK cells,their receptors and function

NK cells are cytotoxic components of innate lymphoid cells (ILC) that provide a first line of defense against viral infections and contribute to control tumor growth and metastasis. Their function is finely regulated by an array of HLA-specific and non-HLA-specific inhibitory and activating receptors which allow to discriminate between healthy and altered cells. Human NK cells gained a major attention in recent years because of the important progresses in understanding their biology and of some promising data in tumor therapy. In this review, we will outline well-established issues of human NK cells and discuss some of the open questions, debates, and recent advances regarding their origin, differentiation, and tissue distribution. Newly defined NK cell specializations, including the impact of inhibitory checkpoints on their function, their crosstalk with other cell types, and the remarkable adaptive features acquired in response to certain virus infections will also be discussed.     

Hypertrophic cardiomyopathy with apical aneurysm: a case of catheter and surgical therapy of sustained monomorphic ventricular tachycardia.

The case is presented of a patient with hypertrophic cardiomyopathy, midventricular obstruction, apical aneurysm, and very frequent episodes of sustained monomorphic ventricular tachycardia (VT) unresponsive to common antiarrhythmic drugs. Left ventricular catheter mapping during sinus rhythm suggested the presence of an extensively scarred apical region; early fractionated ECGs were recorded at the neck of the aneurysm during monomorphic VT, suggesting a possible role of this region as VT substrate. Radiofrequency delivery at these sites stopped the VT and it was no longer inducible; however, it spontaneously recurred the following day. An apical aneurysmectomy, guided by the results of catheter mapping, was performed and was successful in preventing arrhythmic recurrences during 12 months' follow up.     

Biological and clinical relevance of matrix metalloproteinases 2 and 9 in acute myeloid leukaemias and myelodysplastic syndromes

We analysed by immunocytochemistry metalloproteinase (MMP)-2 and MMP-9 expression in bone marrow cells from 54 acute myeloid leukaemia (AML) patients, 153 myelodysplastic syndrome (MDS) patients, and 52 non-haemopathic subjects, in order to evaluate whether MMP expression abnormalities were associated with relevant laboratory or clinical findings. In normal samples MMP-2 was detected in rare myeloid cells, MMP-9 in most maturing myeloid cells. In MDS MMP-2 myeloid levels were higher than in controls (P < 0.0001); MMP-2 and MMP-9 were often co-expressed. Also many erythroblasts expressed MMP-2. There was a positive correlation between MMP-2 erythroblast expression and erythroid dysplasia (P = 0.002) and an inverse correlation between MMP-2 or MMP-9 myeloid expression and blast cell percentage (P = 0.05 and P = 0.04 respectively). High MMP levels in myeloid cells were associated with longer overall survival (P = 0.03) and evolution-free survival (P = 0.04). In AML MMP-2 levels were lower than in MDS (P < 0.0001) and MMP-9 levels lower than in MDS and controls (P < 0.0001). MMP levels did not predict response to therapy. The release of active MMPs was detected by colorimetric analysis in cell cultures from representative MDS and AML cases. In conclusion, we have demonstrated an abnormal MMP expression in AML as well as in MDS. The production and release of these enzymes may influence haematopoietic cell behaviour. In MDS, the detection of MMP deregulated expression may be important also from the clinical point of view: it may provide a useful tool for diagnosis, prognosis and a possible target for experimental treatments.     

Embolic protection device use and its association with procedural safety and long‐term outcomes following saphenous vein graft intervention: An analysis from the British Columbia Cardiac registry

• Coronary stents are commonly deployed using high pressure. However, the duration time of balloon inflation during deployment is still to be determined.
• Vallurupalli and coworkers, in this issue of CCI, show that the stent system takes an average of 33 sec to “accommodate” its pressure during in vitro deployment. In patients, the mean stent inflation time to achieve pressure stability was 104 seconds, ranging from 30 to 380 sec.
• These results challenge a rapid inflation/deflation approach for stent deployment. It is suggested that the duration of the inflation might be individualized, in a case‐by‐case approach.
• However, the findings must be interpreted with caution, as they cannot be directly extrapolated to more diverse clinical, angiographic, and interventional scenarios.

     

Reverse shoulder prosthesis to treat complex proximal humeral fractures in the elderly patients: results after 10-year experience

Purpose

The aim of this study is to report the clinical and radiological results of reverse total shoulder arthroplasty (rTSA) in elderly patients who have been treated for complex humeral fractures.

Materials and methods

From January 2005 to December 2014, we have implanted rTSA for proximal humeral fractures in 95 patients (80 womens, 15 mens) about 75 years old on average (range 62–95 years). All rates and results on intraoperative and postoperative complications have been collected in a specific database. In all cases we have used a modular implant prosthesis (Lima Corporate, San Daniele del Friuli, Italy). The prosthesis was implanted cementless in 92 cases. Because of the presence of a high percentage of comorbidities in the elderly patients, we have retrospectively analyzed the necessity of a secondary hospitalization, from a week to a 6-month time after the discharge, due to general health problems and specific postoperative shoulder complications. The mean follow-up was 5 years (range 1–9 years) for 70 of 95 patients, 50 of whom had adequate radiographic controls.

Results

None of 95 patients has required a reoperation or a hospitalization for general health problems from 1 week to 6 months postoperative. No early or late infection of prosthesis has been observed. There were seven cases of perioperative complications, three humeral vertical bone fissuring, two glenoid fractures and two cases of deltoid muscle damage. We have had three cases of postoperative hematoma and one case of ulnar nerve neuropathy. The mean constant score was 85.4, and the mean simple shoulder test was 7.4. We have observed a grade 1 scapular notching in 15 cases (30 %). In the remaining 35 reviewed cases, there was no notching. Peri-articular heterotopic ossifications were found in 11 cases (22 %).

Conclusion

Reverse shoulder prosthesis in complex humeral fractures in the elderly can be considered as a reliable surgical procedure, which leads to very good clinical and radiological results in case of cementless prosthesis, as well.