Association of Citrus Virus A to Citrus Impietratura Disease Symptoms

Citrus impietratura disease (CID) is a graft transmissible, virus-like disease observed in old-line citrus trees; its characteristic symptom is the appearance of gum in the albedo of the affected fruits. To identify the causal agent of the disease, high-throughput sequencing (HTS) was performed on symptomatic orange fruits. The analysis of the obtained data revealed in all samples mixed infections of viroids commonly found in citrus trees together with the recently described citrus virus A (CiVA). Examination of additional symptomatic fruits with conventional reverse transcription PCR led to the identification of a single CiVA infection in one tree, which was verified by HTS. Indexing of the single CiVA-infected tree on indicator plants resulted in the appearance of characteristic symptoms in the leaves that were correlated with virus accumulation. Moreover, a comparative analysis among symptomatic and asymptomatic fruits derived from the same trees was performed and included the single CiVA-infected orange tree. The analysis revealed a positive correlation between the appearance of symptoms and the accumulation of CiVA RNAs. To facilitate CiVA detection during certification programs of propagation material, a quantitative RT-PCR targeting the movement protein of the virus was developed and evaluated for reliable and sensitive detection of the virus. To the best of our knowledge this is the first study that associates CiVA with the appearance of CID symptoms.

Common CCR 5 polymorphism in stroke: the CCR 5 delta32 polymorphism differentiates cardioembolism from other aetiologies of ischaemic cerebrovascular diseases

Inflammation is involved in the development of atherosclerosis. The CC chemokine receptor 5 (CCR5) initiates chemotaxis and modulates the inflammation secondary to atherosclerosis and related vascular diseases. The CCR5 Delta32 polymorphism influences the expression of CCR5 on the cell surface. The purpose of this study was to examine the effect of the Delta32 polymorphism in ischaemic cerebrovascular disease (ICVD). The CCR5 Delta32 polymorphism was genotyped in 1462 individuals: 562 ischaemic stroke (IS), 97 transient ischaemic attack (TIA) and in 803 healthy controls. All 659 ICVD patients were categorized according to the Trial of Org 10172 in Acute Stroke Treatment aetiological classification. The investigated subtypes were large artery atherosclerosis (LAA), cardioembolism (CE), small artery occlusion (SAO) and cryptogenic disease (CRYPT). Genotyping was performed with the TaqMan polymerase chain reaction. The Delta32 allele was less frequent in CE patients compared with LAA (OR, 0.4; 95% CI, 0.24-0.79; P = 0.008), SAO (OR, 0.5; 95% CI, 0.29-0.84; P = 0.01), CRYPT (OR, 0.5; 95% CI, 0.28-0.82; P = 0.008) and controls (OR, 0.5; 95% CI, 0.36-0.82; P = 0.002). Multiple logistic regression analysis showed that the Delta32 allele is associated with a lower risk for cardioembolic ICVD (OR 0.5; 95% CI, 0.28-0.75; P = 0.002) when compared with ICVD of other causes. The Delta32 polymorphism of CCR5 may differentiate cardioembolism from the remaining causes of ICVD.