Optimal theranostic SPECT imaging protocol for 223radium dichloride therapy.

223Radium dichloride image-based individual dosimetry requires an optimal acquisition and reconstruction protocol and proper image correction methods for theranostic applications. To assess this problem, radium-223 dichloride SPECT images were acquired from a Jaszczak simulator with a dual-headed gamma camera, LEHR collimator, 128 × 128 matrix, and total time of 32 minutes. A cylindrical PMMA phantom was used to calibrate the measurements performed with Jaszczak. The image quality parameters (noise coefficient, contrast, contrast-to-noise ratio and recovery coefficient) and septal penetration correction were calculated by MATLAB®. The best results for the investigated image quality parameters were obtained with an 89 keV energy window (24% wide) produced together with OSEM/MLEM reconstruction (8 subsets and 4 iterations) applying a Butterworth filter (order 10 and cutoff frequency of 0.48 cycles·cm-1). The successfully performed recovery coefficient parameter evaluation allows uptake correction for future patient dosimetry applications.

Noninvasive predictors of esophageal varices in patients with hepatosplenic schistosomiasis mansoni.

BACKGROUND: No previous study have evaluated transient elastography for predicting esophageal varices in hepatosplenic schistosomiasis. AIM: To investigate noninvasive methods of predicting esophageal varices in patients with hepatosplenic schistosomiasis mansoni. METHODS: Cross-sectional multicentric study included 51 patients with hepatosplenic schistosomiasis. Patients underwent ultrasonography-dopplerfluxometry, upper endoscopy, complete blood cell count and transient elastography (Fibroscan®) for liver and spleen stiffness measurement (LSM and SSM). Noninvasive scores previously established for cirrhotic population were studied: platelet count to spleen diameter ratio (PSR), LSM-spleen diameter to platelet ratio score (LSPS) and varices risk score (VRS). We proposed a version of LSPS and VRS by replacing LSM with SSM and named them SSPS and modified-VRS, respectively. RESULTS: Esophageal varices were detected in 42 (82.4%) subjects. Individuals with varices presented higher SSM (73.5 vs 36.3 Kpa, p = 0.001), splenic vein diameter (10.8 vs 8.0 mm, p = 0.017), SSPS (18.7 vs 6.7, p = 0.003) and modified-VRS (4.0 vs 1.4, p = 0.013), besides lower PSR (332 vs 542, p = 0.038), than those without varices. SSPS was independently associated with varices presence (OR=1.19, 95%CI 1.03-1.37, p = 0.020) after multivariate analysis. In a model excluding noninvasive scores, SSM was independently associated with varices diagnosis (OR=1.09, 95%CI 1.03-1.16, p = 0.004). AUROC was 0.856 (95%CI 0.752-0.961, p = 0.001) for SSM and 0.816 (95%CI 0.699-0.932, p = 0.003) for SSPS (p = 0.551). CONCLUSIONS: Spleen-related variables were predictors of esophageal varices: SSM, splenic vein diameter, SSPS, modified-VRS and PSR. Multivariate models indicated that SSM and SSPS are useful tools for predicting varices in non-cirrhotic portal hypertension by hepatosplenic schistosomiasis and may be used in clinical practice.

Changes in gene expression in European eels (Anguilla anguilla) induced by infection with swim bladder nematodes (Anguillicola crassus).

The European eel, Anguilla anguilla, is considered an endangered species that is under pressure for many reasons. Among others, the introduced parasite Anguillicola crassus is thought to play an important role in the decline of eel populations. These nematodes have been shown to negatively affect many fitness-related traits in eels, e.g., growth, osmoregulation, and stress tolerance. Nevertheless, there has been little work on the way in which the host-parasite interaction influences the molecular regulation of these key physiological processes. We experimentally analyzed the effect of this nematode on the expression of genes involved in the physiology of European eels during their continental life. Included are genes that are implicated in the eel's somatic growth (insulin-like growth factor 1 and thyroid hormone receptor beta), osmoregulation (Na+/K+-ATPase beta1 and aquaporin 3), and hematopoiesis (hemoglobin alpha-chain). Our results showed the absence of an effect on genes involved in fish growth; the parasite may, however, have an effect on osmoregulation and hematopoiesis. We also noted a differential impact of male and female parasites on the expression of some genes, perhaps owing to the sexual dimorphism in body size of the parasite.

Dynamic expression of immune response genes in the sea bass, Dicentrarchus labrax, experimentally infected with the monogenean Diplectanum aequans.

The sea bass, Dicentrarchus labrax, is one of the most extensively farmed marine fishes in the Mediterranean. Under the high-density condition common in aquaculture, the monogenean gill parasite Diplectanum aequans can cause significant economic losses. This study used real-time quantitative PCR to investigate the dynamic expression of immune response genes in sea bass infected with Diplectanum aequans. The target genes, interleukin-1 (IL-1beta, transforming growth factor (TGF-beta and T-cell receptor (TCR-beta), were studied in the gills and spleen of the sea bass from the first day of infection until thirty days post- infection. Our results showed that there was an increase in IL-1beta gene expression in the spleen and gills and in TGF-beta gene expression in the gills of infected fish. These results show that parasitic infection induced a local inflammatory reaction and that reaction was restricted to the site of infection. Finally, the absence of relationship between TCR-beta expression and the parasitic infection suggests that the adaptive immune system is not involved in the response against this parasite.