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Whether sex chromosomes are differentiated is an important aspect of our knowledge of dioecious plants, such as date palm (Phoenix dactylifera). In this crop plant, the female individuals produce dates, and are thus the more valuable sex. However, there is no way to identify the sex of date palm plants before reproductive age, and the sex-determining mechanism is still unclear. To identify sex-linked microsatellite markers, we surveyed a set of 52 male and 55 female genotypes representing the geographical diversity of the species. We found three genetically linked loci that are heterozygous only in males. Male-specific alleles allowed us to identify the gender in 100% of individuals. These results confirm the existence of an XY chromosomal system with a nonrecombining XY-like region in the date palm genome. The distribution of Y haplotypes in western and eastern haplogroups allowed us to trace two male ancestral paternal lineages that account for all known Y diversity in date palm. The very low diversity associated with Y haplotypes is consistent with clonal paternal transmission of a nonrecombining male-determining region. Our results establish the date palm as a biological model with one of the most ancient sex chromosomes in flowering plants., (© 2012 IRD. New Phytologist © 2013 New Phytologist Trust.)

Dysphagia occurs in a significant number of individuals with spinal cord injury (SCI) presenting to acute care and inpatient rehabilitation. This prospective study has found dysphagia in nearly 40% of individuals with tetraplegia. Tracheostomy, mechanical ventilation, nasogastric tube, and age are significant risk factors. The detrimental complications of dysphagia in SCI can cause significant morbidity and delays in rehabilitation. Thus, early and accurate diagnosis of dysphagia is imperative to reduce the risk of developing life-threatening complications. Incidence and risk factors of dysphagia and the use of the bedside swallow evaluation (BSE) and videofluoroscopy swallow study (VFSS) to diagnose dysphagia are presented. The often underappreciated role of respiratory therapists, including assist cough, high tidal volume ventilation, and the use of Passy-Muir valve, in the care of individuals with SCI who have dysphagia is discussed. Improved secretion management and respiratory stabilization enable the individuals with dysphagia to be evaluated sooner and safely by a speech pathologist. Early evaluation and intervention could improve upon morbidity and delayed rehabilitation, thus improving overall clinical outcomes.

Background: Dysphagia is a relatively common secondary complication that occurs after acute cervical spinal cord injury (SCI). The detrimental consequences of dysphagia in SCI include transient hypoxemia, chemical pneumonitis, atelectasis, bronchospasm, and pneumonia. The expedient diagnosis of dysphagia is imperative to reduce the risk of the development of life-threatening complications., Objective: The objective of this study was to identify risk factors for dysphagia after SCI and associated respiratory considerations in acute cervical SCI., Methods: Bedside swallow evaluation (BSE) was conducted in 68 individuals with acute cervical SCI who were admitted to an SCI specialty unit. Videofluroscopy swallow study was conducted within 72 hours of BSE when possible., Results: This prospective study found dysphagia in 30.9% (21 out of 68) of individuals with acute cervical SCI. Tracheostomy (P = .028), ventilator use (P = .012), and nasogastric tube (P = .049) were found to be significant associated factors for dysphagia. Furthermore, individuals with dysphagia had statistically higher occurrences of pneumonia when compared with persons without dysphagia (P < .001). There was also a trend for individuals with dysphagia to have longer length of stay (P = .087)., Conclusion: The role of respiratory care practitioners in the care of individuals with SCI who have dysphagia needs to be recognized. Aggressive respiratory care enables individuals with potential dysphagia to be evaluated by a speech pathologist in a timely manner. Early evaluation and intervention for dysphagia could decrease morbidity and improve overall clinical outcomes.

Protein folding stress is a salient feature of the most frequent neurodegenerative diseases. Although the accumulation of abnormally folded proteins is a well-characterized event underlying the pathology, the way cells respond to this phenomenon is not well understood. Signs of endoplasmic reticulum (ER) stress are a common marker of neurodegeneration in many diseases, which may represent two contrasting processes: cell protection events due to activation of adaptive programs, or a chronic stress state that culminates in apoptosis to eliminate irreversibly injured cells. Autophagy has been proposed as a protective mechanism to overcome neurodegeneration that is also modulated by ER stress. In this issue of autophagy Bertrand Mollereau's group provides novel evidence indicating that engagement of nonharmful levels of ER stress protects against experimental Parkinson disease. At the mechanistic level, a homeostatic crosstalk between ER stress signaling and the autophagy pathway was proposed to mediate the therapeutic effects. This study, together with recent findings, supports the involvement of a "hormesis mechanism" to handle degeneration through preconditioning mediated by a dynamic balance between ER stress and autophagy. The implications for aging and future therapeutic development are discussed.

Both autophagy and apoptosis are tightly regulated processes playing a central role in tissue homeostasis. Bax inhibitor 1 (BI-1) is a highly conserved protein with a dual role in apoptosis and endoplasmic reticulum (ER) stress signalling through the regulation of the ER stress sensor inositol requiring kinase 1 α (IRE1α). Here, we describe a novel function of BI-1 in the modulation of autophagy. BI-1-deficient cells presented a faster and stronger induction of autophagy, increasing LC3 flux and autophagosome formation. These effects were associated with enhanced cell survival under nutrient deprivation. Repression of autophagy by BI-1 was dependent on cJun-N terminal kinase (JNK) and IRE1α expression, possibly due to a displacement of TNF-receptor associated factor-2 (TRAF2) from IRE1α. Targeting BI-1 expression in flies altered autophagy fluxes and salivary gland degradation. BI-1 deficiency increased flies survival under fasting conditions. Increased expression of autophagy indicators was observed in the liver and kidney of bi-1-deficient mice. In summary, we identify a novel function of BI-1 in multicellular organisms, and suggest a critical role of BI-1 as a stress integrator that modulates autophagy levels and other interconnected homeostatic processes.

Background: Amaranthus hypochondriacus, a grain amaranth, is a C4 plant noted by its ability to tolerate stressful conditions and produce highly nutritious seeds. These possess an optimal amino acid balance and constitute a rich source of health-promoting peptides. Although several recent studies, mostly involving subtractive hybridization strategies, have contributed to increase the relatively low number of grain amaranth expressed sequence tags (ESTs), transcriptomic information of this species remains limited, particularly regarding tissue-specific and biotic stress-related genes. Thus, a large scale transcriptome analysis was performed to generate stem- and (a)biotic stress-responsive gene expression profiles in grain amaranth., Results: A total of 2,700,168 raw reads were obtained from six 454 pyrosequencing runs, which were assembled into 21,207 high quality sequences (20,408 isotigs + 799 contigs). The average sequence length was 1,064 bp and 930 bp for isotigs and contigs, respectively. Only 5,113 singletons were recovered after quality control. Contigs/isotigs were further incorporated into 15,667 isogroups. All unique sequences were queried against the nr, TAIR, UniRef100, UniRef50 and Amaranthaceae EST databases for annotation. Functional GO annotation was performed with all contigs/isotigs that produced significant hits with the TAIR database. Only 8,260 sequences were found to be homologous when the transcriptomes of A. tuberculatus and A. hypochondriacus were compared, most of which were associated with basic house-keeping processes. Digital expression analysis identified 1,971 differentially expressed genes in response to at least one of four stress treatments tested. These included several multiple-stress-inducible genes that could represent potential candidates for use in the engineering of stress-resistant plants. The transcriptomic data generated from pigmented stems shared similarity with findings reported in developing stems of Arabidopsis and black cottonwood (Populus trichocarpa)., Conclusions: This study represents the first large-scale transcriptomic analysis of A. hypochondriacus, considered to be a highly nutritious and stress-tolerant crop. Numerous genes were found to be induced in response to (a)biotic stress, many of which could further the understanding of the mechanisms that contribute to multiple stress-resistance in plants, a trait that has potential biotechnological applications in agriculture.

Background/objective: Dysphagia following cervical spinal cord injury (SCI) can increase risk for pulmonary complications that may delay the rehabilitative process. The objective of this study was to identify risk factors for dysphagia after cervical SCI., Design: Prospective cohort study., Methods: Individuals with cervical SCI within 31 days of injury underwent a bedside swallow evaluation (BSE) followed by a videofluoroscopy swallow study (VFSS) within 72 hours of the BSE. Subjects were diagnosed as having dysphagia if they had positive findings in either BSE or VFSS., Results: Twenty-nine patients (7 female and 22 male) were enrolled. Of these, 21 (72%) had high cervical tetraplegia (C4 or higher) and 8 (38%) had lower cervical tetraplegia. A tracheostomy was present in 18 (62%) patients; 15 (52%) subjects were on ventilators. Dysphagia was diagnosed in 12 (41%) subjects. Dysphagia was noted in 62% of the subjects with tracheostomy and 53% of the subjects on the ventilator, but only tracheostomy resulted in a statistically significant association with dysphagia (P = 0.047). All three subjects who had nasogastric tubes were diagnosed with dysphagia (P = 0.029). The relationships between dysphagia and gender, high versus low tetraplegia, presence of halo or collar, head injury, and ventilator use were not statistically significant, but age was a significant risk factor (P = 0.028)., Conclusions: Dysphagia is present in about 41% of individuals with acute tetraplegia. Only age, tracheostomy, and nasogastric tubes were identified as significant risk factors for dysphagia for individuals with tetraplegia. No relationship between dysphagia and level of SCI, spine surgery, collar, and ventilator use was found to exist.

Prion-related disorders (PrDs) are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrP(RES). Altered endoplasmic reticulum (ER) homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrP(RES). Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrP(RES) and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models.

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motoneuron degenerative disease characterized by the selective loss of motoneurons in the spinal ventral horn, most brainstem nuclei, and the cerebral cortex. Although approximately 90% of ALS cases are sporadic (sALS), analyses of familial ALS (fALS)-causative genes have generated relevant insight into molecular events involved in the pathology. Here we overview an emerging concept indicating the occurrence of secretory pathway stress in the disease process. These alterations include a failure in the protein folding machinery at the endoplasmic reticulum (ER), engagement of the unfolded protein response (UPR), modifications of the Golgi apparatus network, impaired vesicular trafficking, inhibition of protein quality control mechanisms, oxidative damage to ER proteins, and sustained activation of degradative pathways such as autophagy. A common feature predicted for most of these alterations is abnormal protein homeostasis associated with the accumulation of misfolded proteins at the ER, possibly leading to chronic ER stress and neuronal dysfunction. Signs of ER stress are observed even during presymptomatic stages in fALS mouse models, and pharmacological strategies to alleviate protein misfolding slow disease progression. Because the secretory pathway stress occurs in both sALS and several forms of fALS, it may offer a unique common target for possible therapeutic strategies to treat this devastating disease.

Signal transduction depends critically on the spatial localization of protein constituents. A key question in odor transduction is whether chemotransduction proteins organize into discrete molecular complexes throughout olfactory cilia or distribute homogeneously along the ciliary membrane. Our recordings of Ca(2+) changes in individual cilia with unprecedented spatial and temporal resolution, by the use of two-photon microscopy, provide solid evidence for Ca(2+) microdomains (transducisomes). Dissociated frog olfactory neurons were preloaded with caged-cAMP and fluo-4 acetoxymethyl ester probe Ca(2+) indicator. Ca(2+) influx through cyclic nucleotide-gated (CNG) channels was evoked by uniformly photoreleasing cAMP, while ciliary Ca(2+) was measured. Discrete fluorescence events were clearly resolved. Events were missing in the absence of external Ca(2+) , consistent with the absence of internal Ca(2+) sources. Fluorescence events at individual microdomains resembled single-CNG channel fluctuations in shape, mean duration and kinetics, indicating that transducisomes typically contain one to three CNG channels. Inhibiting the Na(+) /Ca(2+) exchanger or the Ca(2+) -ATPase prolonged the decay of evoked intraciliary Ca(2+) transients, supporting the participation of both transporters in ciliary Ca(2+) clearance, and suggesting that both molecules localize close to the CNG channel. Chemosensory transducisomes provide a physical basis for the low amplification and for the linearity of odor responses at low odor concentrations., (© 2010 The Authors. European Journal of Neuroscience © 2010 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.)

Odour-mediated signal transduction is a complex process that occurs in the cilia of olfactory sensory neurons. To gain insight in to the molecular organization of the odour transduction machinery, we developed a procedure to purify olfactory cilia membranes by differential centrifugation of rat olfactory epithelium extracts. We tested whether known scaffolding proteins that might participate in the assembly of the complex chemotransduction apparatus are present in the purified membrane fraction. Utilizing immunoblotting and immunohistochemistry, we show that the multidomain scaffolding proteins ProSAP/Shanks and calcium/calmodulin-dependent serine protein kinase CASK are present in the olfactory cilia. Ion channels involved in chemotransduction could be reconstituted into planar lipid bilayers for electrophysiological recordings. Our procedure should allow the identification of further chemotransduction-related proteins.

Olfactory sensory neurons respond to odorants increasing Ca(2+) concentrations in their chemosensory cilia. Calcium enters the cilia through cAMP-gated channels, activating Ca(2+)-dependent chloride or potassium channels. Calcium also has a fundamental role in odour adaptation, regulating cAMP turnover rate and the affinity of the cyclic nucleotide-gated channels for cAMP. It has been shown that a Na(+)/Ca(2+) exchanger (NCX) extrudes Ca(2+) from the cilia. Here we confirm previous evidence that olfactory cilia also express plasma membrane Ca(2+)-ATPase (PMCA), and show the first evidence supporting a role in Ca(2+) removal. Both transporters were detected by immunoblot of purified olfactory cilia membranes. The pump was also revealed by immunocytochemistry and immunohistochemistry. Inside-out cilia membrane vesicles transported Ca(2+) in an ATP-dependent fashion. PMCA activity was potentiated by luminal Ca(2+) (K(0.5) = 670 nm) and enhanced by calmodulin (CaM; K(0.5) = 31 nm). Both carboxyeosin (CE) and calmidazolium reduced Ca(2+) transport, as expected for a CaM-modulated PMCA. The relaxation time constant (tau) of the Ca(2+)-dependent Cl(-) current (272 +/- 78 ms), indicative of luminal Ca(2+) decline, was increased by CE (2181 +/- 437 ms), by omitting ATP (666 +/- 49 ms) and by raising pH (725 +/- 65 ms), suggesting a role of the pump on Ca(2+) clearance. Replacement of external Na(+) by Li(+) had a similar effect (tau = 442 +/- 8 ms), confirming the NCX involvement in Ca(2+) extrusion. The evidence suggests that both Ca(2+) transporters contribute to re-establish resting Ca(2+) levels in the cilia following olfactory responses.

Recent evidence suggests that reactive oxygen species function as second messenger molecules in normal physiological processes. For example, activation of N-Methyl-D-Aspartate receptor results in the production of ROS, which appears to be critical for synaptic plasticity, one of the cellular mechanisms that underlie learning and memory. In this work, we studied the effect of iron in the activation of MAPK/ERK pathway and on Ca2+ signaling in neuronal PC12 cells. We found that iron-dependent generation of hydroxyl radicals is likely to modulate Ca2+ signaling through RyR calcium channel activation, which, in turn, activates the MAPK/ERK pathway. These findings underline the relevance of iron in normal neuronal function.

Olfactory cilia contain cyclic nucleotide-gated and Ca2+-dependent Cl- conductances that underlie excitatory chemotransduction, and a Ca2+-dependent K+ (KCa) conductance, apparently involved in inhibitory transduction. Previous single-channel patch-clamp studies on olfactory cilia revealed four different KCas, with different conductances and kinetics. Here, we further characterized these channels in planar bilayers, where blockers could be properly tested. All four ciliary KCas were observed: The 16 pS channel, K0.5,Ca=40 microM and apamin-sensitive; the 30 and 50 pS channel, K0.5,Ca=59 microM, clotrimazole-sensitive and charybdotoxin-insensitive; the 60 pS channel, clotrimazole-sensitive and charybdotoxin-insensitive; and the 210 pS channel, K0.5,Ca=63 microM, blocked by charybdotoxin and iberiotoxin. The presence of the 16 and 210 pS channels was confirmed by immunoblotting.

Background: Psoriasis is a chronic inflammatory skin disease. Probably autoimmune in nature, and associated with streptococcal throat infections as a triggering factor. Although many groups have associated the disease with other pathogens, Streptococcus pyogenes seems to be the most important microorganism related to this disease. Therefore, it is necessary to identify the streptococcal antigens involved in the process., Methods: In this work IgG class antibodies to soluble antigens obtained from Staphyloccus aureus, Candica albicans or S. pyogenes before and after heat shock induction, were analyzed by ELISA in 28 psoriatic patients and 30 healthy donors., Results: In all cases, the patients and the controls had IgG class antibodies to the four antigens. Nevertheless, the IgG levels to the heat shock-induced S. pyognes were statistically different between the patients and the controls (P < 0.001). There was no difference between the groups when the IgG antibodies to the other antigens, including the noninduced streptococcal extract, were analyzed. Additionally, anti-streptolysin O titers and throat cultures were carried out in all patients and controls. No differences between ASO titers were found but the patients were more frequently colonized by pyogenes., Conclusion: Results obtained in this study suggest that heat shock-induced proteins from S. pyogenes are associated with psoriasis.

Objective: Lispro is a newly FDA-approved analog of human insulin that will be widely used in patients with IDDM. This insulin, however, may have an increased potential for hypoglycemia because of its very rapid subcutaneous absorption, especially in a setting of decreased carbohydrate intake. Using a short-term prospective randomized parallel group-study design, we studied the incidence of hypoglycemia when lispro was given before breakfast compared with regular human insulin. Since carbohydrate intake is a determinant of postprandial glycemia, we administered three isocaloric meals characterized by low, average, and high carbohydrate content., Research Design and Methods: Two groups of six IDDM subjects were randomized to receive 0.15 U/kg of lispro or regular human insulin subcutaneously before the ingestion of three 500-kcal breakfast meals of differing carbohydrate content on separate days. Lispro was administered at mealtime, and regular insulin was administered 30 min before mealtime., Results: Postprandial plasma glucose concentrations were decreased in the lispro group compared with the regular-insulin group for all three meal types (P < 0.05), and hypoglycemia developed more frequently and rapidly in the lispro group, compared with the regular-insulin group by survival analysis. Additionally, peak insulin concentrations were higher (P < 0.001) and peaked more rapidly (P < 0.05) in the lispro group, compared with the regular-insulin group., Conclusions: We conclude that lispro has a tendency for early postprandial hypoglycemia compared with regular insulin in the setting of reduced carbohydrate intake. This fact should be told to patients who decide to switch from regular insulin to lispro. Health care professionals should instruct their IDDM patients to monitor glucose levels frequently after switching to lispro since adjustments in their carbohydrate intake and/or their lispro dosage may be necessary to avoid hypoglycemia.