Reduced acquisition time for thallium myocardial perfusion imaging with large field cadmium-zinc-telluride SPECT/CT cameras: An equivalence study

BACKGROUND

Cadmium-zinc-telluride (CZT) SPECT/CT cameras with large field of view offer a higher sensitivity than conventional Anger cameras. This prospective study aimed to determine the equivalence between a conventional protocol and a reduced acquisition time protocol for 201-Thallium myocardial perfusion imaging (MPI) using a whole-body CZT SPECT camera.

METHODS AND RESULTS

Stress MPI was obtained for 103 consecutive patients on a DISCOVERY-CZT camera. Images were anonymized and post-processed to simulate a 25% (D75 dataset) and 50% (D50 dataset) decrease in total recorded counts. Concerning the number of segments displaying a tracer uptake < 70% of maximum intensity per patient, equivalence was demonstrated for both count-reduced datasets with a good inter-observer agreement (between 0.90 and 0.88). When comparing the full-vs-D75 datasets and full-vs-D50 datasets, mean difference was 0.06 segment (CI95: [- 0.15;0.27], P < 0.001) and 0.518 segment (CI95: [0.28;0.76], P < 0.001) respectively. Inter-observer agreement was also moderate to good concerning the number of pathological segments (between 0.6 and 0.7) and excellent for functional parameters.

CONCLUSION

Whole-body CZT SPECT/CT cameras allow to reduce 201-Thallium MPI injected activity or acquisition time by 50% with an equivalence in the number of segments displaying a tracer uptake < 70% of maximum intensity and with a good inter-observer agreement.

Ischemic injury of the upper gastrointestinal tract after out-of-hospital cardiac arrest: a prospective, multicenter study

Background

The consequences of cardiac arrest (CA) on the gastro-intestinal tract are poorly understood. We measured the incidence of ischemic injury in the upper gastro-intestinal tract after Out-of-hospital CA (OHCA) and determined the risk factors for and consequences of gastrointestinal ischemic injury according to its severity.

Methods

Prospective, non-controlled, multicenter study in nine ICUs in France and Belgium conducted from November 1, 2014 to November 30, 2018. Included patients underwent an esophago-gastro-duodenoscopy 2 to 4 d after OHCA if still intubated and the presence of ischemic lesions of the upper gastro-intestinal tract was determined by a gastroenterologist. Lesions were a priori defined as severe if there was ulceration or necrosis and moderate if there was mucosal edema or erythema. We compared clinical and cardiac arrest characteristics of three groups of patients (no, moderate, and severe lesions) and identified variables associated with gastrointestinal ischemic injury using multivariate regression analysis. We also compared the outcomes (organ failure during ICU stay and neurological status at hospital discharge) of the three groups of patients.

Results

Among the 214 patients included in the analysis, 121 (57%, 95% CI 50–63%) had an upper gastrointestinal ischemic lesion, most frequently on the fundus. Ischemic lesions were severe in 55/121 (45%) patients. In multivariate regression, higher adrenaline dose during cardiopulmonary resuscitation (OR 1.25 per mg (1.08–1.46)) was independently associated with increased odds of severe upper gastrointestinal ischemic lesions; previous proton pump inhibitor use (OR 0.40 (0.14–1.00)) and serum bicarbonate on day 1 (OR 0.89 (0.81–0.97)) were associated with lower odds of ischemic lesions. Patients with severe lesions had a higher SOFA score during the ICU stay and worse neurological outcome at hospital discharge.

Conclusions

More than half of the patients successfully resuscitated from OHCA had upper gastrointestinal tract ischemic injury. Presence of ischemic lesions was independently associated with the amount of adrenaline used during resuscitation. Patients with severe lesions had higher organ failure scores during the ICU stay and a worse prognosis.

Clinical Trial RegistrationNCT02349074.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03939-9.

Tibial tubercle torsion, a new factor of patellar instability

INTRODUCTION

External torsion of the anterior tibial tubercle (TT), defined as external rotation around a craniocaudal axis with respect to the posterior femoral condylar plane, may induce patellar instability. To our knowledge no studies have focused on this parameter. The present study aimed to perform an MRI analysis of TT torsion. The study hypothesis was that TT torsion correlates with patellar instability and with 3 of its components: tibial tubercle-trochlear groove (TT-TG) distance, axial engagement index of the patella (AEI), and patellar tilt.

MATERIAL AND METHODS

Four observers performed MRI measurements for 2 groups: 37 patellar instability patients (PI group) with history of at least 2 patellar dislocations, and 50 control patients with meniscal lesion but free from patellofemoral pathology. All measurements were taken from 2 axial slices with the posterior condylar plane as reference.

RESULTS

The intra-class correlation coefficient (ICC) was 0.88. TT torsion correlated with patellar instability, with a mean 5.8̊ in controls and 17.9̊ in the PI group (P<0.001). There were also excellent correlations between TT torsion and TT-TG distance, patellar tilt and patellar lateralization (measured by AEI), with correlation coefficients greater than 0.85.

DISCUSSION

TT torsion is a reproducible measurement, with excellent ICC. It is significantly correlated with patellar instability, with a discrimination threshold of 11.5̊, and correlations with all 3 components of instability. These statistical correlations enable TT torsion to be added to the list of patellar instability factors. Further studies should determine its biomechanical role and assess the contribution of associating TT derotation to medialization or distalization procedures.

LEVEL OF EVIDENCE

III; case-control study.

Lactobacillus acidophilus versus placebo in the symptomatic treatment of irritable bowel syndrome: the LAPIBSS randomized trial

Irritable bowel syndrome is a chronic functional gastrointestinal disorder characterized by abdominal pain/discomfort and altered bowel habits. The use of Lactobacilli as probiotics during irritable bowel syndrome is based on their interesting mechanisms of action and their excellent safety profile but little is known about their clinical efficacy due to the lack of adequately designed clinical trials. The current clinical trial protocol aims to determine the effects of a mixture of Lactobacillus acidophilus NCFM and LAFTI L10 as probiotics to improve irritable bowel syndrome symptoms (LAPIBSS). Eighty patients with a positive diagnosis of irritable bowel syndrome according to Rome III criteria were recruited to a multicentre, double-blinded, in parallel groups, placebo-controlled randomized trial. Patients were provided with a daily dose of two capsules with two strains of Lactobacilli (5x109cfu/capsule) or placebo for 8 weeks on a 1:1 ratio. The primary outcome is to obtain scores of abdominal pain/discomfort assessed with a 100-mm visual analogue scale. The secondary outcome is to obtain scores of bloating, flatus and rumbling tested with a 100-mm visual analogue scale, composite score, stool frequency and stool consistency/appearance assessed with the Bristol Stool Form scale. According to the hypothesis that abdominal pain is mainly the result of a visceral hypersensitivity, the current study protocol aims to provide high quality proof of concept data to elucidate the efficacy of a consumption of a mixture of Lactobacillus acidophilus probiotic strains after 8 weeks, for decreasing abdominal pain. Ethical approval was given by ethics committee French Consultative Committee for the Protection of Individuals in Biomedical Research of the South West (Number CPP08-014a) and ANSM (French National Agency for Medicines and Health Products Safety - Number B80623-40). The findings from LAPBISS will be disseminated through peer-reviewed publications and at scientific conferences.

TRIAL REGISTRATION

EudraCT N°2008-A00844-51.

Systematic review with meta-analysis: direct comparisons of biomarkers for the diagnosis of fibrosis in chronic hepatitis C and B

BACKGROUND

Blood tests and transient elastography (TE), proposed as alternatives to biopsy for identifying advanced fibrosis (METAVIR-stage-F2 or greater) or cirrhosis, have never been compared using an intention to diagnose approach, with direct comparisons only, and Bayesian approach.

AIM

To permit more appropriate comparisons.

METHODS

From an overview of articles (2002-2014), we selected studies that directly compared the diagnostic accuracy of FibroTest, aspartate aminotransferase-platelet ratio index (APRI), FIB4 or TE, with biopsy as a reference, in patients with chronic hepatitis C (CHC) or B (CHB). Investigators abstracted and checked study details and quality by using pre-defined criteria. Bayesian method in intention to diagnose was the primary outcome.

RESULTS

Of 1321 articles identified, 71 studies including 77 groups according to aetiology (All-CB) were eligible: 37 Only-C, 28 Only-B and 12 Mixed-C-B. There were 185 direct comparisons between the area under the ROC curves (AUROCs), 99 for the diagnosis of advanced fibrosis and 86 for cirrhosis. In All-CB, Bayesian analyses revealed significant AUROCs differences in identifying advanced fibrosis in favour of FibroTest vs. TE [credibility interval: 0.06(0.02-0.09)], FibroTest vs. APRI [0.05 (0.03-0.07)] and for identifying cirrhosis TE vs. APRI [0.07 (0.02-0.13)] and FIB4 vs. APRI [0.04(0.02-0.05)]. No differences were observed between TE and FibroTest, for identifying cirrhosis in All-CB, and in sub-groups (Only-C, Only-B, Mixed-CB) for both cirrhosis and fibrosis.

CONCLUSIONS

In CHC and CHB, APRI had lower performances than FIB-4, TE and FibroTest. TE had lower performance than FibroTest for identifying advanced fibrosis in All-CB, without significant difference for identifying cirrhosis in all groups.

Identification of a basal-like subtype and comparative effect of epirubicin-based chemotherapy and sequential epirubicin followed by docetaxel chemotherapy in the PACS 01 breast cancer trial: 33 markers studied on tissue-microarrays (TMA)

509

Background: Immunohistochemical profiling studies with TMA classified breast cancer by luminal, normal breast like, HER-2 overexpressing, and basal-like subtypes. The aim of this study was to evaluate the impact of these subclasses in terms of therapeutic benefit for patients (pts) with node positive operable breast cancer included in the phase III trial PACS01. Methods: Among the 1999 pts randomized, 1100 paraffin blocs were collected for TMA. Pts were treated with either arm A: 6 cycles of FEC100 (546 pts) or arm B: docetaxel 100 mg/m2 replaced FEC100 for the last 3 cycles (554 pts). The median follow up was 5 years. The 33 analysed markers explored different pathways: cellular differentiation (CK5/6,8/18,14, P-Cadherin, E-cadherin, α-catenin, β-catenin, AF6, MUC1, Cav1, moesin, Cd10, CD44), proliferation/apoptosis (AuroraA, Tacc2/3, Ki67, CyclinD1, Bcl2, p21, p27), ER related (ER, PR, Gata3), and oncogene/ antioncogene (P53, HER2, EGFR1, Pten, Cmet, Fhit, FGFR, Angiogenin, topoisomeraseIIα). All antibodies were evaluated in quick score. Results: In terms of metastases free survival (MFS) 16 markers harboured a statistical significant value under 20%. The hierarchical clustering for 80% of complete data, identify a cluster of pts (n=531) characterized by the positive expression of EGFR1, Moesin, Pcadherin, and p53, considered as basal-like subtype (BLST). This cluster presented a pejorative predictive value both in Log-rank test (LR) (p=0.002) and in Cox multivariate analysis (HR=0.65; p=0.009), confirmed in overall survival (OS) (LR p<0.0001; cox HR=0.46, p<0.001). BLST pts had a significantly better MFS (LR p=0.05) in the arm B, confirmed in OS (LR p=0.005), as for a more theoretical basal signature and ER negativity (LR MFS p=0.0033, OS p=0.0052; cox MFS HR=0.71 p=0.04, OS HR=0.51 p=0.003). For a second cluster considered as luminal subtype (ER positive and BLST parameters negatives) no difference was observed whatever the arm. Conclusions: The basal-like profile identified in this study is significantly associated to a worst prognostic, but also to a better response to sequential FEC/docetaxel chemotherapy.

[Table: see text]

Factors influencing the C-O bond homolysis of alkoxyamines: effects of H-bonding and polar substituents

The synthesis of various new trialkylhydroxylamines is described. The rate constant of the C-O bond cleavage of these new alkoxyamines has been measured. For example, C-O bond homolysis rates in a series of para-substituted TEMPO-styryl compounds TEMPO-CH(CH3)C6H5X 1a (p-MeO), 1b (p-Me), 1d (p-H), 1e (p-Br), and 1f (p-MeO2C) are presented. Furthermore, rate constants for the C-O bond cleavage of alpha-heteroaryl-substituted secondary alkoxyamines are discussed. A correlation by which the rate constant for the C-O bond cleavage of TEMPO-derived alkoxyamines can be predicted from the C-H BDEs of the corresponding alkanes is presented. Solvent effects as well as the effect of camphorsulfonic acid on the rate of the C-O bond homolysis are discussed. Finally, EPR and kinetic evidence show that alkoxyamines derived from nitroxides which are capable of intramolecular H-bonding undergo C-O bond cleavage faster than the corresponding non-H-bond-forming analogues.