Outcome of patients with atrial fibrillation after intravenous thrombolysis for cerebral ischaemia

The question of whether i.v. rt-PA is beneficial in patients with ischaemic stroke and atrial fibrillation (AF) remains unresolved. Our objective was to evaluate the outcome of patients with AF who received i.v. rt-PA for stroke in the registries of Lille (France) and Belgrade (Serbia). End-points were poor outcome [modified Rankin Scale (mRS) 3–6], and symptomatic haemorrhagic transformation (sHT) according to ECASS3. Of 734 consecutive patients, 155 (21.2 %) had AF. The unadjusted comparison found patients with AF to be 12 years older, more likely to be women, to have hypertension, and baseline INR > 1.2, and less likely to be smokers. They had higher baseline NIHSS scores, diastolic blood pressure, and serum glucose concentrations, and lower platelet counts. They did not differ for sHT (5.8 vs. 5.5 %; p = 0.893), but they more frequently had poor outcomes (52.3 vs. 35.2 %; p < 0.001) and death (21.9 vs. 9.0 %; p < 0.001). The only independent predictor of sHT was baseline NIHSS (_adjOR 1.05 per 1 point increase; 95 % CI 1.01–1.10). Independent variables associated with poor outcome were age (_adjOR 1.04 for 1 year increase; 95 % CI 1.03–1.06), baseline NIHSS (_adjOR 1.17 per 1 point increase; 95 % CI 1.13–1.21), and sHT (_adjOR 47.6; 95 % CI 10.2–250) but not AF. In patients treated with i.v. rt-PA for cerebral ischaemia, those with AF have worse outcomes because they are older and have more severe strokes at admission. This result suggests that we should focus on prevention and research of more aggressive strategies at the acute stage.     

Catechol-O-methyltransferase Val158Met polymorphism and hyperactivity symptoms in Egyptian children with autism spectrum disorder

Catechol-O-methyltransferase (COMT) plays an important role in the catabolism of brain dopamine and norepinephrine, which have been implicated in the pathogenesis of Autism spectrum disorder (ASD) as well as in other neuropsychatric disorders. We aimed to investigate the association of COMT Val158Met gene polymorphism with ASD and to examine the influence of such genotypes on hyperactivity symptoms in ASD patients. Eighty ASD patients (mean age 9 ± 1.9 years) and 100 control children (mean age 8.9 ± 1.9 years) were examined. COMT Val58Met polymorphism was genotyped using Tetra-primer ARMS-PCR method. The clinical diagnosis of ASD and ADHD were confirmed according to the DSM-IV criteria for research. We found no significant difference in genotypes or alleles’ frequencies of COMT Val158Met polymorphism between ASD patients and control group. There was a significant association between COMT (Val/Val) genotype and both increasing CARS (p = 0.001) and hyperactivity scores (p = 0.006). Regarding Conner's Score, the DSM-IV hyperactive impulsive were significantly higher in Val/Val genotype than both Met/Val and Met/Met genotypes (p = 0.03). Our data suggested an association between COMT Val58Met polymorphism and hyperactivity symptoms in Egyptian children with ASD.     

Depletion of the Plasmodium berghei thrombospondin-related sporozoite protein reveals a role in host cell entry by sporozoites

The malaria parasite sporozoite stage develops in the mosquito vector and is transmitted to the mammalian host by bite. Sporozoites engage in multiple interactions with vector and host tissue on the journey from their oocyst origin to their final destination inside hepatocytes. Several malaria proteins have been identified that mediate sporozoite interactions with target tissues such as secreted and surface-associated ligands CSP and TRAP, which contain a thrombospondin type 1 repeat (TSR). Recently, we identified thrombospondin-related sporozoite protein (TRSP) in Plasmodium sporozoites, which exhibits a single TSR in its putative extracellular N-terminal region and is highly conserved among Plasmodium species. Here, we show using targeted gene disruption in the rodent malaria model Plasmodium berghei, that lack of TRSP has no effect on the asexual blood stage cycle, parasite transmission to the mosquito, sporozoite development and infection of mosquito salivary glands. However, analysis of TRSP knockout sporozoites in vitro and in vivo indicates that this protein has a significant role in hepatocyte entry and therefore liver infection. Thus, TRSP is an additional TSR-containing malaria parasite protein that is mainly involved in initial infection of the mammalian host.     

Radiation effect on late cardiopulmonary toxicity: An analysis comparing supine DIBH versus prone techniques for breast treatment

Two commonly used whole breast irradiation (WBI) techniques, deep inspiration breath hold (DIBH) and prone positioning, are compared with regard to dosimetry and estimated late cardiac morbidity and secondary lung cancer mortality using published models. Forty patients with left‐sided DCIS or breast cancer who underwent lumpectomy and required adjuvant WBI were enrolled on a prospective trial comparing supine DIBH (S‐DIBH) with prone free breathing (P‐FB) planning. Patients underwent CT simulation in both positions; two plans were generated for each patient. Comparative dosimetry was available for 34 patients. Mean cardiac and lung doses were calculated. Risk of death from ischemic heart disease (IHD), risk of at least one acute coronary event (ACE), and lung cancer mortality were estimated from published data. Difference between S‐DIBH and P‐FB plans was compared using paired two‐tailed t test. Estimated mean risk of death from IHD by age 80 was 0.1% (range 0.0%‐0.2%) for both plans (P = 1.0). Mean risk of at least one ACE was 0.3% (range 0.1%‐0.6%) for both plans (P = .6). Mean lung cancer mortality risk was 1.4% (range 0.5%‐15.4%) for S‐DIBH and 1.0% (range 0.4%‐9.8%) for P‐FB (P = .008). Excess lung cancer mortality due to radiation was 0.5% (range 0.1%‐6.0%) with S‐DIBH and 0.0% (range 0.0%‐0.4%) with P‐FB (P = .008). Both S‐DIBH and P‐FB provide excellent cardiac sparing. Prone positioning results in lower lung dose than S‐DIBH and leads to an absolute decrease of 0.5% in excess lung cancer mortality for patients receiving WBI.     

Signaling through ZAP-70 is required for CXCL12-mediated T-cell transendothelial migration

Transendothelial migration of activated lymphocytes from the blood into the tissues is an essential step for immune functions. The housekeeping chemokine CXCL12 (or stroma cell-derived factor-1alpha), a highly efficient chemoattractant for T lymphocytes, drives lymphocytes to sites where they are highly likely to encounter antigens. This suggests that cross-talk between the T-cell receptor (TCR) and CXCR4 (the CXCL12 receptor) might occur within these sites. Here we show that the zeta-associated protein 70 (ZAP-70), a key element in TCR signaling, is required for CXCR4 signal transduction. The pharmacologic inhibition of ZAP-70, or the absence of ZAP-70 in Jurkat T cells and in primary CD4(+) T cells obtained from a patient with ZAP deficiency, resulted in an impairment of transendothelial migration that was rescued by the transfection of ZAP-70. Moreover, the overexpression of mutated forms of ZAP-70, whose kinase domain was inactivated, also abrogated the migratory response of Jurkat T cells to CXCL12. In contrast, no involvement of ZAP-70 in T-cell arrest on inflammatory endothelium under flow conditions or in CXCL12-induced actin polymerization was observed. Furthermore, CXCL12 induced time-dependent phosphorylation of ZAP-70, Vav1, and extracellular signal-regulated kinases (ERKs); the latter were reduced in the absence of functional ZAP-70. However, though a dominant-negative Vav1 mutant (Vav1 L213A) blocked CXCL12-induced T-cell migration, pharmacologic inhibition of the ERK pathway did not affect migration, suggesting that ERK activation is dispensable for T-cell chemotaxis. We conclude that cross-talk between the ZAP-70 signaling pathway and the chemokine receptor CXCR4 is required for T-cell migration.