Futile import of tRNAs and proteins into the mitochondrion of Trypanosoma brucei evansi

Trypanosoma brucei brucei has two distinct developmental stages, the procyclic stage in the insect and the bloodstream stage in the mammalian host. The significance of each developmental stage is punctuated by specific changes in metabolism. In the insect, T. b. brucei is strictly dependent on mitochondrial function and thus respiration to generate the bulk of its ATP, whereas in the mammalian host it relies heavily on glycolysis. These observations have raised questions about the importance of mitochondrial function in the bloodstream stage. Peculiarly, akinetoplastic strains of Trypanosoma brucei evansi that lack mitochondrial DNA do exist in the wild and are developmentally locked in the glycolysis-dependent bloodstream stage. Using RNAi we show that two mitochondrion-imported proteins, mitochondrial RNA polymerase and guide RNA associated protein 1, are still imported into the nucleic acids-lacking organelle of T. b. evansi, making the need for these proteins futile. We also show that, like in the T. b. brucei procyclic stage, the mitochondria of both bloodstream stage of T. b. brucei and T. b. evansi import various tRNAs, including those that undergo thiolation. However, we were unable to detect mitochondrial thiolation in the akinetoplastic organelle. Taken together, these data suggest a lack of connection between nuclear and mitochondrial communication in strains of T. b. evansi that lost mitochondrial genome and that do not required an insect vector for survival.     

Comprehensive clinicopathological,molecular, and methylation analysis of mesenchymal tumors with NTRK and other kinase gene aberrations

Alterations in kinase genes such as NTRK1/2/3, RET, and BRAF underlie infantile fibrosarcoma (IFS), the emerging entity ‘NTRK-rearranged spindle cell neoplasms’ included in the latest WHO classification, and a growing set of tumors with overlapping clinical and pathological features. In this study, we conducted a comprehensive clinicopathological and molecular analysis of 22 cases of IFS and other kinase gene-altered spindle cell neoplasms affecting both pediatric and adult patients. Follow-up periods for 16 patients ranged in length from 10 to 130 months (mean 38 months). Six patients were treated with targeted therapy, achieving a partial or complete response in five cases. Overall, three cases recurred and one metastasized. Eight patients were free of disease, five were alive with disease, and two patients died. All cases showed previously reported morphological patterns. Based on the cellularity and level of atypia, cases were divided into three morphological grade groups. S100 protein and CD34 were at least focally positive in 12/22 and 14/22 cases, respectively. Novel PWWP2A::RET, NUMA1::RET, ITSN1::RAF1, and CAPZA2::MET fusions, which we report herein in mesenchymal tumors for the first time, were detected by RNA sequencing. Additionally, the first uterine case with BRAF and EGFR mutations and CD34 and S100 co-expression is described. DNA sequencing performed in 13 cases uncovered very rare additional genetic aberrations. The CNV profiles showed that high-grade tumors demonstrate a significantly higher percentage of copy number gains and losses across the genome compared with low- and intermediate-grade tumors. Unsupervised clustering of the tumors’ methylation profiles revealed that in 8/9 cases, the methylation profiles clustered with the IFS methylation class, irrespective of their clinicopathological or molecular features. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.     

Consequent effects of the great cormorant (Phalacrocorax carbo sinensis) predation on parasite infection and body condition of common carp (Cyprinus carpio)

Lesions ranging from surface wounds to deep tissue wounds caused by cormorant predation were observed on several species of the farmed fish in Pohořelice, Czech Republic. Two-year-old stocked common carp Cyprinus carpio harvested in late March were examined for ectoparasites and endoparasites, injuries extent, and lysozyme concentration in skin mucus. Additionally, three body condition indices were measured. Endoparasite infection occurred only scarcely. Wounded fish were more susceptible to the ectoparasites Gyrodactylus spp. and Dactylogyrus spp. (Monogenea), and Ichthyophthirius multifiliis (Ciliophora). The intensity of infection of other ectoparasites Eudiplozoon nipponicum (Monogenea), Argulus spp. (Branchiura) and trichodinids (Ciliophora) did not significantly differ between wounded and control groups of fish. Lysozyme concentration in fish mucus was significantly higher in wounded fish and was positively associated with both the extent of damaged epithelium and Gyrodactylus spp. abundance. There were no differences in Fulton’s condition factor and lipid content in muscle and liver tissues between wounded and non-wounded fish. Higher values of spleen-somatic index in wounded fish corresponded to increased intensity of parasite infection, most likely reflecting changes in immune system of infected fish. Although our results did not show any significant effect of cormorant attacks on fish condition, the wounded fish had significantly higher parasite numbers which could impact the growth or survival of the fish throughout the production season.     

Uric acid,allopurinol therapy,and mortality in patients with acute heart failure—results of the Acute HEart FAilure Database registry

Study Objective

The aim of this study was to explore the prognostic role of serum uric acid (UA) measurement in the hospital and long-term mortality assessment in subjects with acute heart failure (AHF) from the Acute HEart FAilure Database registry (AHEAD). The AHEAD registry comprised 4153 patients with AHF syndromes hospitalized at the AHEAD participating centers.

Patients and Methods

The study included 1255 patients who were admitted to the AHEAD participating centers with acute decompensated chronic heart failure, de novo heart failure, or cardiogenic shock between September 2006 and October 2009 and who had information about serum UA concentration available at the time of hospital admission. The hospital and long-term mortality was followed using the centralized database of the Ministry of Health, Czech Republic.The mean age of the cohort was 73.4 years, the female population represented 43%, the median hospital stay was 8 days, and the mean hospital mortality was 7.6%.

Results

The median UA concentration of the patients with AHF was 432 μmol/L (7.26 mg/dL), the median estimated glomerular filtration rate (eGFR) was 49.0 mL/min, and N-terminal pro–brain natriuretic peptide level was 5510 pg/mL. Among other laboratory variables, UA concentration greater than 515 μmol/L (8.67 mg/dL) was associated with increased hospital mortality (P < .001), as well as eGFR less than 30 mL/min (P < .001), Na 135 mmol/L or less, and positive troponin. Uric acid concentration greater than 500 μmol/L (8.41 mg/dL) was associated with increased long-term mortality (P < .001), followed by eGFR less than 30 mL/min (P < .001), Na 135 mmol/L or less, and hemoglobin level lower than 130 g/L (P < .001). The 1-year survival rate of patients discharged from hospital (n = 1159) was 75.6%, and the 2-year rate was 66.8%. Survival of patients treated with allopurinol for hyperuricemia was significantly lower compared with untreated subjects (70.1 vs 77.2 for 1-year survival and 60.3 vs 68.5 for 2-year survival).

Conclusion

In patients with AHF, increased UA levels and documented allopurinol therapy for hyperuricemia were associated with increased hospital and long-term mortality. Allopurinol therapy is not a cause but the identifier of the subjects at risk.     

Computational and experimental investigation of needle-shaped crystal breakage

Needle-shaped crystals are a common occurrence in many pharmaceutical and fine chemicals processes. Even if the particle size distribution (PSD) obtained in a crystallization step can be controlled by the crystal growth kinetics and hydrodynamic conditions, further fluid-solid separation steps such as filtration, filter washing, drying, and subsequent solids handling can often lead to uncontrolled changes in the PSD due to breakage. In this contribution we present a combined computational and experimental methodology for determining the breakage kernel and the daughter distribution functions of needle-shaped crystals, and for population balance modeling of their breakage. A discrete element model (DEM) of needle-shaped particle breakage was first used in order to find out the appropriate types of the breakage kernel and the daughter distribution functions. A population balance model of breakage was then formulated and used in conjunction with experimental data in order to determine the material-specific parameters appearing in the breakage functions. Quantitative agreement between simulation and experiment has been obtained.     

Soluble receptor for advanced glycation end products in physiological and pathological pregnancy

ObjectiveThe receptor for advanced glycation end products, RAGE, has been implicated in pathogenesis of many diseases. Soluble RAGE, sRAGE, extracellular domain of RAGE, is new biomarker. The aim of the study was to determine sRAGE levels in physiological pregnancy and their changes in pregnancies complicated by preterm labor or preeclampsia.Design and methodsSerum levels of sRAGE were determined in 79 healthy pregnant women, 42 pregnant women in preterm labor or with preeclampsia and 24 non-pregnant controls.ResultssRAGE serum levels are decreased in physiological pregnancy compared to healthy non-pregnant controls (p < 0.001). Serum sRAGE concentrations are higher in the 2nd trimester of physiological pregnancy, compared to the 1st and 3rd trimesters of pregnancy (p < 0.001). sRAGE levels in women with preterm labor are decreased (p < 0.05) and correlate negatively with the leukocyte count (r = -0.47, p < 0.05). In women with preeclampsia, sRAGE is elevated (p < 0.05) and correlates with serum creatinine concentration (r = 0.54, p < 0.05) and with uric acid concentration (r = 0.51, p < 0.05).ConclusionOur results clearly demonstrate significant differences in serum sRAGE levels in physiological pregnancy and in pathological states in pregnancy, however, further studies are required demonstrate the usefulness and significance of sRAGE.     

Cost‐effectiveness of hematopoietic stem cell mobilization strategies including plerixafor in multiple myeloma and lymphoma patients

Peripheral blood stem cells (PBSCs) are preferred source of hematopoietic stem cells for autologous transplantation. Mobilization of PBSCs using chemotherapy and/or granulocyte colony‐stimulating factor (G‐CSF) however fails in around 20%. Combining G‐CSF with plerixafor increases the mobilizations success. We compared cost‐effectiveness of following schemes: the use of plerixafor “on demand” (POD) during the first mobilization in all patients with inadequate response, the remobilization with plerixafor following failure of the first standard mobilization (SSP), and the standard (re)mobilization scheme without plerixafor (SSNP). Decision tree models populated with data from a first‐of‐a‐kind patient registry in six Czech centers (n = 93) were built to compare clinical benefits and direct costs from the payer's perspective. The success rates and costs for POD, SSP and SSNP mobilizations were; 94.9%, $7,197; 94.7%, $8,049; 84.7%, $5,991, respectively. The direct cost per successfully treated patient was $7,586, $8,501, and $7,077, respectively. The cost of re‐mobilization of a poor mobilizer was $5,808 with G‐CSF only and $16,755 if plerixafor was added. The total cost of plerixafor “on‐demand” in the sub‐cohort of poor mobilizers was $17,120. Generally, plerixafor improves the mobilization success by 10% and allows an additional patient to be successfully mobilized for incremental $11,803. Plerixafor is better and cheaper if used “on demand” than within a subsequent remobilization. J. Clin. Apheresis 28:395–403, 2013. © 2013 Wiley Periodicals, Inc.