Behavior and Impact of Zirconium in the Soil–Plant System: Plant Uptake and Phytotoxicity

Because of the large number of sites they pollute, toxic metals that contaminate terrestrial ecosystems are increasingly of environmental and sanitary concern (Uzu et al. 2010, 2011; Shahid et al. 2011a, b, 2012a). Among such metals is zirconium (Zr), which has the atomic number 40 and is a transition metal that resembles titanium in physical and chemical properties (Zaccone et al. 2008). Zr is widely used in many chemical industry processes and in nuclear reactors (Sandoval et al. 2011; Kamal et al. 2011), owing to its useful properties like hardness, corrosion-resistance and permeable to neutrons (Mushtaq 2012). Hence, the recent increased use of Zr by industry, and the occurrence of the Chernobyl and Fukashima catastrophe have enhanced environmental levels in soil and waters (Yirchenko and Agapkina 1993; Mosulishvili et al. 1994 ; Kruglov et al. 1996)

Histone methyltransferase Dot1 and Rad9 inhibit single-stranded DNA accumulation at DSBs and uncapped telomeres

Cells respond to DNA double-strand breaks (DSBs) and uncapped telomeres by recruiting checkpoint and repair factors to the site of lesions. Single-stranded DNA (ssDNA) is an important intermediate in the repair of DSBs and is produced also at uncapped telomeres. Here, we provide evidence that binding of the checkpoint protein Rad9, through its Tudor domain, to methylated histone H3-K79 inhibits resection at DSBs and uncapped telomeres. Loss of DOT1 or mutations in RAD9 influence a Rad50-dependent nuclease, leading to more rapid accumulation of ssDNA, and faster activation of the critical checkpoint kinase, Mec1. Moreover, deletion of RAD9 or DOT1 partially bypasses the requirement for CDK1 in DSB resection. Interestingly, Dot1 contributes to checkpoint activation in response to low levels of telomere uncapping but is not essential with high levels of uncapping. We suggest that both Rad9 and histone H3 methylation allow transmission of the damage signal to checkpoint kinases, and keep resection of damaged DNA under control influencing, both positively and negatively, checkpoint cascades and contributing to a tightly controlled response to DNA damage

Labrum repair combined with arthroscopic reduction of capsular volume in shoulder instability

We performed arthroscopic treatment of traumatic anterior and anteroinferior shoulder instability combining three procedures— labrum repair, reduction of capsular volume and suture of the rotator cuff interval—with the aim of analysing the results with regard to stability and function. Between January 1999 and December 2003, 27 patients underwent arthroscopic treatment for labrum repair with metal anchors, reduction of capsular volume through thermal capsulorrhaphy and suture of rotator cuff interval. These patients were evaluated in the pre- and postoperative period using the UCLA and Rowe scales and in the postoperative period using the ASES scale. During a mean follow-up period of 32.4 months (range 22–74 months) all shoulders remained stable. Using the UCLA scale, there was improvement from the preoperative period, with a mean score of 24.7, to the postoperative period, with a mean of 32.81. Improvement was also shown by the Rowe scale, with a mean score of 39.81 in the preoperative period and 90.74 in the postoperative period. On the ASES scale the mean score was 92.22. All shoulders remained stable and there was marked functional improvement in the patients who were treated. These results are comparable to those obtained with open surgery, observing similar patient selection criteria