Esketamine counters opioid-induced respiratory depression

Background

Opioids can produce life-threatening respiratory depression. This study tested whether subanaesthetic doses of esketamine stimulate breathing in an established human model of opioid-induced respiratory depression.

Comprehensive assessment of spotty calcifications on computed tomography angiography: Comparison to plaque characteristics on intravascular ultrasound with radiofrequency backscatter analysis

Background

The purpose of the study was to systematically compare calcification patterns in plaques on computed tomography angiography (CTA) with plaque characteristics on intravascular ultrasound with radiofrequency backscatter analysis (IVUS-VH).

Methods and Results

In total, 108 patients underwent CTA and IVUS-VH. On CTA, calcification patterns in plaques were classified as non-calcified, spotty or dense calcifications. Plaques with spotty calcifications were differentiated into small spotty (<1 mm), intermediate spotty (1-3 mm) and large spotty calcifications (≥3 mm). Plaque characteristics deemed more high-risk on IVUS-VH were defined by % necrotic core (NC) and presence of thin cap fibroatheroma (TCFA). Overall, 300 plaques were identified both on CTA and IVUS-VH. % NC core was significantly higher in plaques with small spotty calcifications as compared to non-calcified plaques (20% vs 13%, P = .006). In addition, there was a trend for a higher % NC in plaques with small spotty calcifications than in plaques with intermediate spotty calcifications (20% vs 14%, P = .053). Plaques with small spotty calcifications had the highest % TCFA as compared to large spotty and dense calcifications (31% vs 9% and 31% vs 6%, P < .05).

Conclusion

Plaques with small spotty calcifications on CTA were related to plaque characteristics deemed more high-risk on IVUS-VH. Therefore, CTA may be valuable in the assessment of the vulnerable plaque.     

Comparison of the relation between the calcium score and plaque characteristics in patients with acute coronary syndrome versus patients with stable coronary artery disease, assessed by computed tomography angiography and virtual histology intravascular ultrasound

A considerable number of patients with an acute coronary syndrome (ACS) who present with a 0 or low calcium score (CS) still demonstrate coronary artery disease (CAD) and significant stenosis. The aim of the present study was to evaluate the relation between the CS and the degree and character of atherosclerosis in patients with suspected ACS versus patients with stable CAD obtained by computed tomography angiography and virtual histology intravascular ultrasound (VH IVUS). Overall 112 patients were studied, 53 with ACS and 59 with stable CAD. Calcium scoring and computed tomography angiography were performed and followed by VH IVUS. On computed tomography angiography each segment was evaluated for plaque and classified as noncalcified, mixed, or calcified. Vulnerable plaque characteristics on VH IVUS were defined by percent necrotic core and presence of thin-cap fibroatheroma. If the CS was 0, patients with ACS had a higher mean number of plaques (5.0 ± 2.0 vs 2.0 ± 1.9, p <0.05) and noncalcified plaques (4.6 ± 3.5 vs 1.3 ± 1.9, p <0.05) on computed tomography angiography than those with stable CAD. If the CS was 0, VH IVUS demonstrated that patients with ACS had a larger amount of necrotic core area (0.58 ± 0.73 vs 0.22 ± 0.43 mm(2), p <0.05) and a higher mean number of thin-cap fibroatheromas (0.6 ± 0.7 vs 0.1 ± 0.3, p <0.05) than patients with stable CAD. In conclusion, even in the presence of a 0 CS, patients with ACS have increased plaque burden and increased vulnerability compared to patients with stable CAD. Therefore, absence of coronary calcification does not exclude the presence of clinically relevant and potentially vulnerable atherosclerotic plaque burden in patients with ACS.     

Multicolor flow cytometry for evaluation of platelet surface antigens and activation markers

Introduction

Flow cytometry allows the analysis of multiple antigens in a single tube at a single cell level. We present a rapid and sensitive two tube flow cytometric protocol for the detection of multiple platelet antigens and activation markers gated on a pure platelet population.

Materials and methods

The presence of platelet specific antigens was analyzed in citrated whole blood of normal platelets and from patients diagnosed with platelet abnormalities. Quiescent platelets as well as stimulated platelets were analyzed using a gating strategy based on ubiquitously expressed platelet membrane markers.A ubiquitously expressed platelet marker was combined with antibodies against the activated alpha2b-beta3 (PAC-1), Lysosomal Activated Membrane Protein (CD63) and P-selectin (CD62P).

Results

We were able to detect the platelet antigens CD36, CD41, CD42a, CD42b and CD61 in one single tube. Our approach allowed the single tube determination of PAC-1, CD63 and CD62P after activation of platelets by thrombin, collagen, ADP and PAR-1, and determination of platelet abnormalities.

Conclusions

Our two tube multi-parameter screening protocol is suited for the analysis of platelet antigens expressed on quiescent and activated platelets and allows the detection of aberrancies as found in blood of patients with thrombocytopathy such as Glanzmann Thrombasthenia, storage pool disease with diminished granule content and patients treated with clopidogrel and acetylsalicylic acid.     

Assessment of global left ventricular function and volumes with 320-row multidetector computed tomography: A comparison with 2D-echocardiography

Background  

Multidetector computed tomography (MDCT) has been demonstrated as a feasible imaging modality for noninvasive assessment of coronary artery disease and left ventricular (LV) function. Recently, 320-row systems have become available with 16 cm anatomical coverage allowing image acquisition of the entire heart within a single heartbeat. The purpose of this study was to evaluate the accuracy of 320-row MDCT in the assessment of global LV function compared to two-dimensional (2D) echocardiography as the standard of reference.     

Relationship of birth weight to the pathogenesis of necrotizing enterocolitis in the neonatal piglet

The relationship between birth weight and the development of necrotizing enterocolitis (NEC) was studied in the term-delivered neonatal piglet. Hypoxia (pO2 less than 30% for 1 h) coupled with hyperviscosity (hematocrit more than 75%), with and without splenectomy, resulted in a high frequency and severity of NEC. This effect was most pronounced in low birth weight (LBW) animals. A statistically significant inverse relationship was found between birth weight and the number and severity of lesions. Splenectomy increased the incidence and severity of lesions particularly in LBW animals. A predominance of lesions was found in the distal ileum with occasional occurrences elsewhere in the small bowel and in the proximal colon. The neonatal piglet is capable of producing the full spectrum of NEC under acceptable experimental conditions. LBW is a significant predisposing factor in the pathogenesis of NEC.     

Rhabdomyosarcoma, presenting as a facial swelling in a child. A case report and review of the literature

A case of the very rare rhabdomyosarcoma as the more common second primary in a young child who had been treated for bilateral, genetic retinoblastoma is described and the importance early diagnosis emphasised. A review of the literature is presented with special reference to the prognosis of head and neck rhabdomyosarcoma and the various treatment alternatives, related to both new primary and secondary tumours in children with retinoblastoma.