Paclitaxel and Caffeine-Taurine, New Colchicine Alternatives for Chromosomes Doubling in Maize Haploid Breeding.

The doubled haploid (DH) technology is employed worldwide in various crop-breeding programs, especially maize. Still, restoring tassel fertility is measured as one of the major restrictive factors in producing DH lines. Colchicine, nitrous oxide, oryzalin, and amiprophosmethyl are common chromosome-doubling agents that aid in developing viable diploids (2n) from sterile haploids (n). Although colchicine is the most widely used polyploidy-inducing agent, it is highly toxic to mammals and plants. Therefore, there is a dire need to explore natural, non-toxic, or low-toxic cheaper and accessible substitutes with a higher survival and fertility rate. To the best of our knowledge, the advanced usage of human anticancer drugs "Paclitaxel (PTX)" and "Caffeine-Taurine (CAF-T)" for in vivo maize haploids doubling is being disclosed for the first time. These two antimitotic and antimicrotubular agents (PTX and CAF-T) were assessed under various treatment conditions compared to colchicine. As a result, the maximum actual doubling rates (ADR) for PTX versus colchicine in maize haploid seedlings were 42.1% (400 M, 16 h treatment) versus 31.9% (0.5 mM, 24 h treatment), respectively. In addition, the ADR in maize haploid seeds were CAF-T 20.0% (caffeine 2 g/L + taurine 12 g/L, 16 h), PTX 19.9% (100 µM, 24 h treatment), and colchicine 26.0% (2.0 mM, 8 h treatment). Moreover, the morphological and physiological by-effects in haploid plants by PTX were significantly lower than colchicine. Hence, PTX and CAF-T are better alternatives than the widely used traditional colchicine to improve chromosome-doubling in maize crop.

Relationship between vertebral artery hypoplasia and posterior circulation stroke in Chinese patients.

INTRODUCTION: Vertebral artery hypoplasia (VAH), which has been found in about 10 % of normal individuals, does not produce symptoms but may be associated with an increased risk of cerebral posterior circulation ischemic (PCI) stroke. The aims of this study were to determine the prevalence of VAH in Chinese patients with cerebral infarction and investigate whether VAH is an independent risk factor for PCI stroke. METHODS: The medical records of 841 Chinese stroke patients were reviewed retrospectively. All patients underwent either cervical contrast-enhanced magnetic resonance angiography (CE-MRA) or cervical computed tomography angiography (CTA). There is no standard definition of VAH; we defined it as a vertebral artery < 2 mm in diameter and the whole artery was slim or absent on CE-MRA or CTA. Univariate and multivariate logistic regression analyses were performed to identify significant independent risk factors for PCI stroke. RESULTS: There were 230 patients (27.3 %) diagnosed with PCI stroke and 91 patients diagnosed with VAH (10.8 %). Multivariate logistic regression analysis showed that VAH, male gender, and stenosis of the posterior circulation were independent risk factors for PCI stroke. CONCLUSIONS: Our results show that VAH is not rare in Chinese patients with stroke and that its presence increases the risk of PCI stroke.

Value of imaging lenticulostriate arteries before middle cerebral artery stenting for the prevention of perforator stroke.

INTRODUCTION: In this study, we investigated whether pre-procedural imaging of LSAs would potentially be helpful for preventing LSAs from being covered. METHODS: We retrospectively evaluated the LSAs of 15 consecutive patients who underwent revascularization for symptomatic middle cerebral artery (MCA) stenosis. All patients underwent two- (2D) and three-dimensional (3D) digital subtraction angiography. RESULTS: We found that 46.7 (7/15), 40 (6/15), and 13.3 % (2/15) of patients had stenotic lesions in the proximal, middle, and distal third of the M1 segment, respectively. There was a total of 32 LSAs that originated from the lesioned MCAs. Seven (21.9 %), 10 (31.3 %), 11 (34.4 %), and 4 (12.5 %) LSAs originated from the proximal third of the M1 segment, middle third of the M1 segment, distal third of the M1 segment, and starting segment of the superior M2 segment, respectively. Sixteen (76.2 %) of 22 LSAs in 13 patients were covered by stents. It would have been possible to avoid covering 43.8 % (7/16) of these LSAs with stents if they had been evaluated before stenting, and the stents had been accurately deployed. Among 16 LSAs which were covered by stent, only one (6.25 %) was occluded after coverage. CONCLUSION: Our data suggest that evaluation of LSAs during MCA stenting would be potentially helpful for preventing LSAs from being covered and subsequently occluded by stents.