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Grafting provides a simple way to generate chimeric plants with regions of different genotypes and thus to assess the cell autonomy of gene action. The technique of grafting has been widely used in other species, but in Arabidopsis, its small size makes the process rather more demanding. However, there are now several well-established grafting procedures available, which we described here, and their use has already contributed greatly to understanding of such processes as shoot branching control, flowering, disease resistance, and systemic silencing.

A high performance liquid chromatography method, adapted from an established urinary sugars method, has been developed for the analysis of a tetraglucose oligomer (Glc(4)) in urine. Pompe disease results from defects in the activity of lysosomal acid α-glucosidase (GAA) with patients typically excreting increased amounts of Glc(4). Rapid determination of GAA in dried blood spots is now possible. However, enzymatic analysis is unable to discriminate between patients with Pompe disease and those individuals harbouring pseudo deficiency mutations. This method was able to quantify Glc(4) levels in all patients analysed with an established diagnosis of Pompe disease, and all controls analysed had Glc(4) levels below the limit of detection for this method. Importantly the method was able to discriminate between an individual known to harbour a pseudo Pompe mutation and patients with Pompe disease, providing a useful supporting test to enzymatic analysis. Sequential measurement of urinary Glc(4) has been proposed to monitor the effects of enzyme replacement therapy (ERT). We observed a clear decrease in Glc(4) levels following commencement of treatment in three patients studied. Additionally, raised levels of Glc(4) were observed in patients with glycogen storage disease (GSD) type Ia and type III suggesting that this method may have applications in other GSDs.

The current treatment of mucopolysaccharidosis type II (MPS II, Hunter syndrome) is enzyme replacement therapy with recombinant idursulfase (Elaprase®). The efficacy of ERT was established based primarily on reduction in urine glycosaminoglycans:creatinine (GAG:Cr) ratio and improvement in a composite score of predicted forced vital capacity (FVC% predicted) and 6-min walk-test distance (6MWT). We retrospectively reviewed these parameters in 11 boys with MPS II treated with idursulfase between April 2007 (or the time of diagnosis) and February 2010. Some results were inconsistent with published trial data, and there was only a small number of analyzable results obtained for the FVC% predicted and 6MWT. A major drawback was the high prevalence of neurological involvement and young age of patients in the study cohort compared with the clinical trials. This study emphasizes the limitations of the current tools utilized to monitor ERT efficacy and MPS II disease burden in clinical practice.

One of the most striking features of plant architecture is the regular arrangement of leaves and flowers around the stem, known as phyllotaxis. Peaks in concentration of the plant hormone auxin, generated by the polar localization of the PIN1 auxin efflux carrier, provide the instructive signal for primordium initiation. This mechanism generates the spacing between neighboring primordia, which results in regular phyllotaxis. Studies of the role of auxin transport in phyllotactic patterning have focused on PIN1-mediated efflux. Recent computer simulations indicate an additional role for transporter-mediated auxin uptake. Mutations in the AUX1 auxin influx carrier have not, however, been reported to cause an aerial phenotype. Here, we study the role of AUX1 and its paralogs LAX1, LAX2, and LAX3. Analysis of the quadruple mutant reveals irregular divergence angles between successive primordia. A highly unusual aspect of the phenotype is the occurrence of clusters of primordia, in violation of classical theory. At the molecular level, the sharp peaks in auxin levels and coordinated PIN polarization are reduced or lost. In addition, the increased penetrance of the phenotype under short-day conditions suggests that the AUX LAX transporters act to buffer the PIN-mediated patterning mechanism against environmental or developmental influences.

Studies of apical dominance have benefited greatly from two-branch assays in pea and bean, in which the shoot system is trimmed back to leave only two active cotyledonary axillary branches. In these two-branch shoots, a large body of evidence shows that one actively growing branch is able to inhibit the growth of the other, prompting studies on the nature of the inhibitory signals, which are still poorly understood. Here, we describe the establishment of two-branch assays in Arabidopsis, using consecutive branches on the bolting stem. As with the classical studies in pea and bean, these consecutive branches are able to inhibit one another's growth. Not only can the upper branch inhibit the lower branch, but also the lower branch can inhibit the upper branch, illustrating the bi-directional action of the inhibitory signals. Using mutants, we show that the inhibition is partially dependent on the MAX pathway and that while the inhibition is clearly transmitted across the stem from the active to the inhibited branch, the vascular connectivity of the two branches is weak, and the MAX pathway is capable of acting unilaterally in the stem.

Abnormal rhabdomyocyte expression of cardiac troponin-T (cTnT) was thought to interfere with the cTnT assay. cTnT isoforms have been shown to be transiently expressed in skeletal muscle during development and in response to muscle denervation. The effect of denervation and aging on cTnT and cardiac troponin-I (cTnI) content in fast and slow rat skeletal muscles was assessed quantitatively. Sections of the tibial nerve were transected from one hind limb of both young (n=12) and old (n=12) rats. Animals were sacrificed at 1, 2, and 4 weeks after the operation, and the extensor digitorum longus (EDL) and the soleus were removed from both the denervated and the contralateral control limb. There was no significant difference in cTnI content between the fast EDL and slow soleus muscles. The cTnT content was significantly higher in the soleus than the EDL muscle (p<0.001). These data, combined with data on other models in the literature, indicate that re-expression of cTnT and cTnI isoforms in adult skeletal muscle is unlikely and does not interfere with cTnT assays for assessment of cardiac damage.

Study Objectives: There are contradictory perspectives on the importance of conventional coronary heart disease (CHD) risk factors in explaining population levels and social gradients in CHD. This study examined the contribution of conventional CHD risk factors (smoking, hypertension, dyslipidaemia, and diabetes) to explaining population levels and to absolute and relative social inequalities in CHD. This was investigated in an entire population and by creating a low risk sub-population with no smoking, dyslipidaemia, diabetes, and hypertension to simulate what would happen to relative and social inequalities in CHD if conventional risk factors were removed., Design, Setting, and Participants: Population based study of 2682 eastern Finnish men aged 42, 48, 54, 60 at baseline with 10.5 years average follow up of fatal (ICD9 codes 410-414) and non-fatal (MONICA criteria) CHD events., Main Results: In the whole population, 94.6% of events occurred among men exposed to at least one conventional risk factor, with a PAR of 68%. Adjustment for conventional risk factors reduced relative social inequality by 24%. However, in a low risk population free from conventional risk factors, absolute social inequality reduced by 72%., Conclusions: Conventional risk factors explain the majority of absolute social inequality in CHD because conventional risk factors explain the vast majority of CHD cases in the population. However, the role of conventional risk factors in explaining relative social inequality was modest. This apparent paradox may arise in populations where inequalities in conventional risk factors between social groups are low, relative to the high levels of conventional risk factors within every social group. If the concern is to reduce the overall population health burden of CHD and the disproportionate population health burden associated with the social inequalities in CHD, then reducing conventional risk factors will do the job.

Objective: To assess if the combination of cardiac troponin (cTn) and Ischemia Modified Albumin (IMA) can be used for early exclusion of acute myocardial infarction (AMI)., Methods: Prospective consecutive admissions to the emergency department (ED) with undifferentiated chest pain were assessed clinically and by electrocardiography. A total of 539 patients (335 men, 204 women; median age 51.9 years) considered at low risk of AMI had blood drawn on admission. If the first sample was less than 12 hours from onset of chest pain, a second sample was drawn two hours later, at least six hours from onset of chest pain. Creatine kinase MB isoenzyme (CKMB) mass was measured on the first sample and CKMB mass and cTnT on the second sample. An aliquot from the first available sample was frozen and subsequently analysed for IMA. If cTnT had not been measured on the original sample cTnI was measured (n = 189)., Results: Complete data were available for 538/539 patients. IMA or cTn was elevated in the admission sample of all patients with a final diagnosis of AMI (n = 37) with IMA alone elevated in 2/37, cTn alone in 19/37, and both in 16/37. In 173/501 patients in whom AMI was excluded both tests were negative. In the non-AMI group 22 patients had elevation of both IMA and cTn in the initial sample, suggesting ischaemic disease., Conclusion: Admission measurement of cardiac troponin plus IMA can be used for early classification of patients presenting to the ED to assist in patient triage.

Grafting provides a simple way to generate chimeric plants with regions of different genotypes, and thus to assess the cell autonomy of gene action. The technique of grafting has been widely used in other species, but in Arabidopsis, its small size makes the process rather more complicated. However, there are now several well-established grafting procedures available, which we described here, and their use has already contributed greatly to understanding of such processes as shoot branching control, flowering, and disease resistance.

The Arabidopsis MORE AXILLARY BRANCHING 4 (MAX4) gene is required for the production of a long-range, graft-transmissible signal that inhibits shoot branching. Buds of max4 mutant plants are resistant to the inhibitory effects of apically applied auxin, indicating that MAX4 is required for auxin-mediated bud inhibition. The RAMOSUS 1 (RMS1) and DECREASED APICAL DOMINANCE 1 (DAD1) genes of pea and petunia, respectively, are orthologous to MAX4 and function in a similar way. Here we show that, despite the similarities between these three genes, there are significant differences in the regulation of their expression. RMS1 is known to be upregulated by auxin in the shoot, suggesting a straightforward link between the RMS1-dependent branch-inhibiting signal and auxin, whereas we find that MAX4 is only upregulated by auxin in the root and hypocotyl, and this is not required for the inhibition of shoot branching. Furthermore, both RMS1 and DAD1 are subject to feedback regulation, for which there is no evidence for MAX4. Instead, overexpression studies and reciprocal grafting experiments demonstrate that the most functionally significant point of interaction between auxin and MAX4 is post-transcriptional and indeed post-synthesis of the MAX4-dependent graft-transmissible signal.

Shoot branching is inhibited by auxin transported down the stem from the shoot apex. Auxin does not accumulate in inhibited buds and so must act indirectly. We show that mutations in the MAX4 gene of Arabidopsis result in increased and auxin-resistant bud growth. Increased branching in max4 shoots is restored to wild type by grafting to wild-type rootstocks, suggesting that MAX4 is required to produce a mobile branch-inhibiting signal, acting downstream of auxin. A similar role has been proposed for the pea gene, RMS1. Accordingly, MAX4 and RMS1 were found to encode orthologous, auxin-inducible members of the polyene dioxygenase family.

Previously, the cognitive recovery of a 26 year old woman, Kate, who developed a severe encephalomyelopathy and was in a 'minimally conscious/persistent vegetative state' for 6 months was reported. After 6 months, Kate began to respond to her environment and, at 2 years post-illness, neuropsychological assessment indicated that Kate was functioning within the normal range on tests of general intellectual functioning, executive functioning and most memory functions (with the exception of visual recognition memory). Although Kate has a severe dysarthria necessitating the use of a communication board and severe physical disabilities that require her to use a wheelchair, she has demonstrated an almost complete cognitive recovery and is among a tiny percentage of minimally conscious patients to do so. This single case report describes the emotional factors central to Kate's rehabilitation. Using a newly developed model of cognitive rehabilitation as a framework, the pivotal role that emotional and psychological factors played in Kate's adjustment to the consequences of her illness and the role of psychotherapeutic intervention in facilitating this adjustment are discussed.

Background: Qualitative and quantitative measures of cardiac troponin I (cTnI) in striated muscle have been reported as part of diverse investigations. However, there is disparity in the literature regarding the findings of these analyses. The cTnI molecule can exist in phosphorylated, non-phosphorylated, reduced, non-reduced, complexed or non-complexed forms. Each of these forms can change the antigenicity of cTnI, resulting in different antibody-antigen interactions in different experimental formats, thereby giving rise to the disparities in the literature., Methods: cTnI in heart and skeletal muscles were investigated by three techniques employing the same specific cTnI antibodies: the recently revised Dade-Behring Dimension RXL assay, immunoblotting and immunohistochemistry., Results: cTnI was detected in heart muscle but not skeletal muscle using the quantitative assay and immunoblotting. Unexpectedly, using the same antibodies, cTnI was not immunolocalized to either heart or skeletal muscle., Conclusion: The antibody-cTnI interaction might be impeded on fixed immunohistochemistry sections. Our findings reflect those of a previous study, showing that cTnI was not detected in skeletal muscle extracts using a quantitative assay. The behaviour of cTnI antibodies varies depending on experimental design. Conclusions drawn from experiments using qualitative methods cannot necessarily be extrapolated to the quantitative assay and vice versa.

This study reports on the case of a young woman who, at the age of 26, developed a severe encephalomyelopathy and was in a vegetative state or minimally conscious state for 6 months. She showed a sleep-wake cycle, but no evidence of cognitive functioning. Six months after her illness, she began to respond to her environment and eventually returned home to the care of her parents, with regular periods of respite care in a home for people with severe physical disabilities. She remains in a wheelchair with a severe dysarthria and communicates via a letter board. Two years after her illness, staff at the home requested an assessment of her cognitive functioning. On the WAIS-R verbal scale and the Raven's Progressive Matrices, the woman's scores were in the normal range. So too were her recognition of real versus nonsense words and her memory functioning (apart from a visual recognition memory test which was in the impaired range). Although she enjoyed the tests, she became distressed when asked about her illness and previous hospitalization. She was reassessed 1 year later, when there were few significant changes in her test scores but she could talk about her illness and hospitalization without becoming distressed. She was angry, however, about her experiences in the first hospital. Further tests suggested good executive functioning. In short, this woman's cognitive functioning is in the normal range for most tasks assessed, despite a severe physical disability and dysarthria, and despite the fact that she was vegetative for 6 months. Although some recovery following 6 months of being vegetative/minimally conscious is not unknown, it is rare, particularly for those with non-traumatic injuries, and the majority of people similarly affected remain with significant cognitive deficits. This client has, by and large, made an almost complete cognitive recovery. She feels positive about her life now and says the formal assessment showed people she was not stupid and this made her happy. The paper concludes with the young woman's own comments and views about what happened to her and her present feelings.