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Chemical fertilizers and pesticides are essential aids in current agricultural practice to achieve the growing population's need worldwide. Excessive use of these agrochemicals often exerts toxic effects and imposes acute risks on human health and the surrounding environment. Importantly, they have negative impacts on the farmers during agricultural practice without proper safety measures. When a human comes in contact with these toxic chemicals due to leaching and drifting causes serious health hazards including diabetes, reproductive disorders, neurological dysfunction, cancer, and respiratory diseases. In this paper, we discussed the benefits and adverse effects of agrochemicals on humans and the ecology. Moreover, we also discussed some important remedial measures to reduce the toxic effects in farming. We have mentioned recent state-of-art nanotechnology techniques to improve agricultural research. This paper will give new insights into current farming strategies by which farmers will be able to decrease the application of chemical fertilizers and pesticides.

Damage to respiratory neural circuitry and consequent loss of diaphragm function is a major cause of morbidity and mortality after cervical spinal cord injury (SCI). Upon SCI, inspiratory signals originating in the medullary rostral ventral respiratory group (rVRG) become disrupted from their phrenic motor neuron (PhMN) targets, resulting in diaphragm paralysis. Limited growth of both damaged and spared axon populations occurs after central nervous system trauma attributed, in part, to expression of various growth inhibitory molecules, some that act through direct interaction with the protein tyrosine phosphatase sigma (PTPσ) receptor located on axons. In the rat model of C2 hemisection SCI, we aimed to block PTPσ signaling to investigate potential mechanisms of axon plasticity and respiratory recovery using a small molecule peptide mimetic that inhibits PTPσ. The peptide was soaked into a biocompatible gelfoam and placed directly over the injury site immediately after hemisection and replaced with a freshly soaked piece 1 week post-SCI. At 8 weeks post-hemisection, PTPσ peptide significantly improved ipsilateral hemidiaphragm function, as assessed in vivo with electromyography recordings. PTPσ peptide did not promote regeneration of axotomized rVRG fibers originating in ipsilateral medulla, as assessed by tracing after adeno-associated virus serotype 2/mCherry injection into the rVRG. Conversely, PTPσ peptide stimulated robust sprouting of contralateral-originating rVRG fibers and serotonergic axons within the PhMN pool ipsilateral to hemisection. Further, relesion through the hemisection did not compromise diaphragm recovery, suggesting that PTPσ peptide-induced restoration of function was attributed to plasticity of spared axon pathways descending in contralateral spinal cord. These data demonstrate that inhibition of PTPσ signaling can promote significant recovery of diaphragm function after SCI by stimulating plasticity of critical axon populations spared by the injury and consequently enhancing descending excitatory input to PhMNs.

We tested a biomaterial-based approach to preserve the critical phrenic motor circuitry that controls diaphragm function by locally delivering minocycline hydrochloride (MH) following cervical spinal cord injury (SCI). MH is a clinically-available antibiotic and anti-inflammatory drug that targets a broad range of secondary injury mechanisms via its anti-inflammatory, anti-oxidant and anti-apoptotic properties. However, MH is only neuroprotective at high concentrations that cannot be achieved by systemic administration, which limits its clinical efficacy. We have developed a hydrogel-based MH delivery system that can be injected into the intrathecal space for local delivery of high concentrations of MH, without damaging spinal cord tissue. Implantation of MH hydrogel after unilateral level-C4/5 contusion SCI robustly preserved diaphragm function, as assessed by in vivo recordings of compound muscle action potential (CMAP) and electromyography (EMG) amplitudes. MH hydrogel also decreased lesion size and degeneration of cervical motor neuron somata, demonstrating its central neuroprotective effects within the injured cervical spinal cord. Furthermore, MH hydrogel significantly preserved diaphragm innervation by the axons of phrenic motor neurons (PhMNs), as assessed by both detailed neuromuscular junction (NMJ) morphological analysis and retrograde PhMN labeling from the diaphragm using cholera toxin B (CTB). In conclusion, our findings demonstrate that local MH hydrogel delivery to the injured cervical spinal cord is effective in preserving respiratory function after SCI by protecting the important neural circuitry that controls diaphragm activation.

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types., Graphical abstract, D’Antonio et al. characterize associations between GWAS signals for COVID-19 disease and eQTLs in 69 human tissues to identify causal variants and their underlying molecular mechanisms. They show that diverse symptoms and disease severity of COVID-19 are associated with variants affecting gene expression in a wide variety of tissues.

Psychotic depression was initially considered to be at one end of a continuum of severity of major depression. Subsequent experience demonstrated that psychosis is an independent trait that may accompany mood disorders of varying severity. While much has been learned about the impact of severe mood congruent delusions and hallucinations on the course and treatment response of depression, less is known about fleeting or mild psychosis, mood incongruent features, or psychotic symptoms that reflect traumatic experiences. Acute treatment of psychotic unipolar depression generally involves the combination of an antidepressant and an antipsychotic drug or electroconvulsive therapy. There is inadequate information about maintenance treatment of unipolar psychotic depression and acute and chronic treatment of psychotic bipolar disorder. Decision-making therefore still must rely in part on clinical experience.

Chondroitin sulfate proteoglycans (CSPGs), up-regulated in and around the lesion after traumatic spinal cord injury (SCI), are key extracellular matrix inhibitory molecules that limit axon growth and consequent recovery of function. CSPG-mediated inhibition occurs via interactions with axonal receptors, including leukocyte common antigen- related (LAR) phosphatase. We tested the effects of a novel LAR inhibitory peptide in rats after hemisection at cervical level 2, a SCI model in which bulbospinal inspiratory neural circuitry originating in the medullary rostral ventral respiratory group (rVRG) becomes disconnected from phrenic motor neuron (PhMN) targets in cervical spinal cord, resulting in persistent partial-to-complete diaphragm paralysis. LAR peptide was delivered by a soaked gelfoam, which was placed directly over the injury site immediately after C2 hemisection and replaced at 1 week post-injury. Axotomized rVRG axons originating in ipsilateral medulla or spared rVRG fibers originating in contralateral medulla were separately assessed by anterograde tracing via AAV2-mCherry injection into rVRG. At 8 weeks post-hemisection, LAR peptide significantly improved ipsilateral hemidiaphragm function, as assessed in vivo with electromyography recordings. LAR peptide promoted robust regeneration of ipsilateral-originating rVRG axons into and through the lesion site and into intact caudal spinal cord to reach PhMNs located at C3-C5 levels. Furthermore, regenerating rVRG axons re-established putative monosynaptic connections with their PhMNs targets. In addition, LAR peptide stimulated robust sprouting of both modulatory serotonergic axons and contralateral-originating rVRG fibers within the PhMN pool ipsilateral/caudal to the hemisection. Our study demonstrates that targeting LAR-based axon growth inhibition promotes multiple forms of respiratory neural circuit plasticity and provides a new peptide-based therapeutic strategy to ameliorate the devastating respiratory consequences of SCI.

Populations of neural stem cells (NSCs) reside in a number of defined niches in the adult central nervous system (CNS) where they continually give rise to mature cell types throughout life, including newly born neurons. In addition to the prototypical niches of the subventricular zone (SVZ) and subgranular zone (SGZ) of the hippocampal dentate gyrus, novel stem cell niches that are also neurogenic have recently been identified in multiple midline structures, including circumventricular organs (CVOs) of the brain. These resident NSCs serve as a homeostatic source of new neurons and glial cells under intact physiological conditions. Importantly, they may also have the potential for reparative processes in pathological states such as traumatic spinal cord injury (SCI) and traumatic brain injury (TBI). As the response in these novel CVO stem cell niches has been characterized after stroke but not following SCI or TBI, we quantitatively assessed cell proliferation and the neuronal and glial lineage fate of resident NSCs in three CVO nuclei—area postrema (AP), median eminence (ME), and subfornical organ (SFO) —in rat models of cervical contusion-type SCI and controlled cortical impact (CCI)-induced TBI. Using bromodeoxyuridine (BrdU) labeling of proliferating cells, we find that TBI significantly enhanced proliferation in AP, ME, and SFO, whereas cervical SCI had no effects at early or chronic time-points post-injury. In addition, SCI did not alter NSC differentiation profile into doublecortin-positive neuroblasts, GFAP-expressing astrocytes, or Olig2-labeled cells of the oligodendrocyte lineage within AP, ME, or SFO at both time-points. In contrast, CCI induced a pronounced increase in Sox2- and doublecortin-labeled cells in the AP and Iba1-labeled microglia in the SFO. Lastly, plasma derived from CCI animals significantly increased NSC expansion in an in vitro neurosphere assay, whereas plasma from SCI animals did not exert such an effect, suggesting that signaling factors present in blood may be relevant to stimulating CVO niches after CNS injury and may explain the differential in vivo effects of SCI and TBI on the novel stem cell niches.

We developed an innovative biomaterial-based approach to repair the critical neural circuitry that controls diaphragm activation by locally delivering brain-derived neurotrophic factor (BDNF) to injured cervical spinal cord. BDNF can be used to restore respiratory function via a number of potential repair mechanisms; however, widespread BDNF biodistribution resulting from delivery methods such as systemic injection or lumbar puncture can lead to inefficient drug delivery and adverse side effects. As a viable alternative, we developed a novel hydrogel-based system loaded with polysaccharide-BDNF particles self-assembled by electrostatic interactions that can be safely implanted in the intrathecal space for achieving local BDNF delivery with controlled dosing and duration. Implantation of BDNF hydrogel after C4/C5 contusion-type spinal cord injury (SCI) in female rats robustly preserved diaphragm function, as assessed by in vivo recordings of compound muscle action potential and electromyography amplitudes. However, BDNF hydrogel did not decrease lesion size or degeneration of cervical motor neuron soma, suggesting that its therapeutic mechanism of action was not neuroprotection within spinal cord. Interestingly, BDNF hydrogel significantly preserved diaphragm innervation by phrenic motor neurons (PhMNs), as assessed by detailed neuromuscular junction morphological analysis and retrograde PhMN labeling from diaphragm using cholera toxin B. Furthermore, BDNF hydrogel enhanced the serotonergic axon innervation of PhMNs that plays an important role in modulating PhMN excitability. Our findings demonstrate that local BDNF hydrogel delivery is a robustly effective and safe strategy to restore diaphragm function after SCI. In addition, we demonstrate novel therapeutic mechanisms by which BDNF can repair respiratory neural circuitry.SIGNIFICANCE STATEMENT Respiratory compromise is a leading cause of morbidity and mortality following traumatic spinal cord injury (SCI). We used an innovative biomaterial-based drug delivery system in the form of a hydrogel that can be safely injected into the intrathecal space for achieving local delivery of brain-derived neurotrophic factor (BDNF) with controlled dosing and duration, while avoiding side effects associated with other delivery methods. In a clinically relevant rat model of cervical contusion-type SCI, BDNF hydrogel robustly and persistently improved diaphragmatic respiratory function by enhancing phrenic motor neuron (PhMN) innervation of the diaphragm neuromuscular junction and by increasing serotonergic innervation of PhMNs in ventral horn of the cervical spinal cord. These exciting findings demonstrate that local BDNF hydrogel delivery is a safe and robustly effective strategy to maintain respiratory function after cervical SCI.

Presynaptic voltage-gated K+ (Kv) channels in dorsal root ganglion (DRG) neurons are thought to regulate nociceptive synaptic transmission in the spinal dorsal horn. However, the Kv channel subtypes responsible for this critical role have not been identified. The Kv3.4 channel is particularly important because it is robustly expressed in DRG nociceptors, where it regulates action potential (AP) duration. Furthermore, Kv3.4 dysfunction is implicated in the pathophysiology of neuropathic pain in multiple pain models. We hypothesized that, through their ability to modulate AP repolarization, Kv3.4 channels in DRG nociceptors help to regulate nociceptive synaptic transmission. To test this hypothesis, we investigated Kv3.4 immunoreactivity (IR) in the rat cervical superficial dorsal horn (sDH) in both sexes and implemented an intact spinal cord preparation to investigate glutamatergic synaptic currents from second order neurons in the sDH under conditions that selectively inhibit the Kv3.4 current. We found presynaptic Kv3.4 IR in peptidergic and nonpeptidergic nociceptive fibers of the sDH. The Kv3.4 channel is hypersensitive to 4-aminopyridine and tetraethylammonium (TEA). Accordingly, 50 μm 4-aminopyridine and 500 μm TEA significantly prolong the AP, slow the maximum rate of repolarization in small-diameter DRG neurons, and potentiate monosynaptic excitatory postsynaptic currents (EPSCs) in dorsal horn laminae I and II through a presynaptic mechanism. In contrast, highly specific inhibitors of BK, Kv7, and Kv1 channels are less effective modulators of the AP and have little to no effect on EPSCs. The results strongly suggest that presynaptic Kv3.4 channels are major regulators of nociceptive synaptic transmission in the spinal cord.SIGNIFICANCE STATEMENT Intractable neuropathic pain can result from disease or traumatic injury and many studies have been conducted to determine the underlying pathophysiological changes. Voltage-gated ion channels, including the K+ channel Kv3.4, are dysregulated in multiple pain models. Kv3.4 channels are ubiquitously expressed in the dorsal root ganglion (DRG), where they are major regulators of DRG excitability. However, little is known about the ionic mechanisms that regulate nociceptive synaptic transmission at the level of the first synapse in the spinal cord, which is critical to pain transmission in both intact and pathological states. Here, we show that Kv3.4 channels have a significant impact on glutamatergic synaptic transmission in the dorsal horn, further illuminating its potential as a molecular pain therapeutic target., This work was supported by the Vickie and Jack Farber Foundation (M.C.), the Dean's Transformational Science Award (M.C.), the National Institutes of Health (Grant NS079855 to M.C. and Grant NS079702 to A.C.L.), the Dubbs Fellowship Fund (T.M.), Sigma Xi (GIAR Grant G20141015648241 to T.M.), Autifony Therapeutics, Ltd. (M.C.), and the Luso-American Development Foundation (V.P.). We thank Drs. Matthew Dalva, Melanie Elliott, Ethan Goldberg, David Ritter, and Benjamin Zemel, and members of the Covarrubias laboratory for helpful comments and feedback on previous versions of this manuscript; members of the Dalva laboratory for sharing reagents; and Dr. Bruce Bean for providing helpful tips regarding the effects of Kv channel inhibitors on the AP in the DRG., info:eu-repo/semantics/publishedVersion

More than half of spinal cord injury (SCI) cases occur in the cervical region, leading to respiratory dysfunction due to damaged neural circuitry that controls critically important muscles such as the diaphragm. The C3-C5 spinal cord is the location of phrenic motor neurons (PhMNs) that are responsible for diaphragm activation; PhMNs receive bulbospinal excitatory drive predominately from supraspinal neurons of the rostral ventral respiratory group (rVRG). Cervical SCI results in rVRG axon damage, PhMN denervation, and consequent partial-to-complete paralysis of hemidiaphragm. In a rat model of C2 hemisection SCI, we expressed the axon guidance molecule, brain-derived neurotrophic factor (BDNF), selectively at the location of PhMNs (ipsilateral to lesion) to promote directed growth of rVRG axons toward PhMN targets by performing intraspinal injections of adeno-associated virus serotype 2 (AAV2)-BDNF vector. AAV2-BDNF promoted significant functional diaphragm recovery, as assessed by in vivo electromyography. Within the PhMN pool ipsilateral to injury, AAV2-BDNF robustly increased sprouting of both spared contralateral-originating rVRG axons and serotonergic fibers. Furthermore, AAV2-BDNF significantly increased numbers of putative monosynaptic connections between PhMNs and these sprouting rVRG and serotonergic axons. These findings show that targeting circuit plasticity mechanisms involving the enhancement of synaptic inputs from spared axon populations is a powerful strategy for restoring respiratory function post-SCI.—Charsar, B. A., Brinton, M. A., Locke, K., Chen, A. Y., Ghosh, B., Urban, M. W., Komaravolu, S., Krishnamurthy, K., Smit, R., Pasinelli, P., Wright, M. C., Smith, G. M., Lepore, A. C. AAV2-BDNF promotes respiratory axon plasticity and recovery of diaphragm function following spinal cord injury.

Compromise in inspiratory breathing following cervical spinal cord injury (SCI) is caused by damage to descending bulbospinal axons originating in the rostral ventral respiratory group (rVRG) and consequent denervation and silencing of phrenic motor neurons (PhMNs) that directly control diaphragm activation. In a rat model of high-cervical hemisection SCI, we performed systemic administration of an antagonist peptide directed against phosphatase and tensin homolog (PTEN), a central inhibitor of neuron-intrinsic axon growth potential. PTEN antagonist peptide (PAP4) robustly restored diaphragm function, as determined with electromyography (EMG) recordings in living SCI animals. PAP4 promoted substantial, long-distance regeneration of injured rVRG axons through the lesion and back toward PhMNs located throughout the C3–C5 spinal cord. These regrowing rVRG axons also formed putative excitatory synaptic connections with PhMNs, demonstrating reconnection of rVRG-PhMN-diaphragm circuitry. Lastly, re-lesion through the hemisection site completely ablated functional recovery induced by PAP4. Collectively, our findings demonstrate that axon regeneration in response to systemic PAP4 administration promoted recovery of diaphragmatic respiratory function after cervical SCI.

The overall goal of our research is to establish a preformed molecular guidance pathway to direct the growth of dopaminergic axons from embryonic ventral mesencephalon (VM), tissue placed within the substantia nigra (SN), into the striatum to reconstruct the nigrostriatal pathway in a hemi-Parkinson's disease rat model. Guidance pathways were prepared by injecting lentivirus encoding either GFP or a combination of glial-cell-line-derived neurotrophic factor (GDNF) with either GDNF family receptor α1 (GFRα1) or netrin1. In another cohort of animals, adeno-associated virus (AAV) encoding brain-derived neurotrophic factor (BDNF) was injected within the striatum after guidance pathway formation. GDNF combined with either GFRα1 or netrin significantly increased growth of dopaminergic axons out of transplants and along the pathway, resulting in a significant reduction in the number of amphetamine-induced rotations. Retrograde tract tracing showed that the dopaminergic axons innervating the striatum were from A9 neurons within the transplant. Increased dopaminergic innervation of the striatum and improved behavioral recovery were observed with the addition of BDNF. Preformed guidance pathways using a combination of GDNF and netrin1 can be used to reconstruct the nigrostriatal pathway and improve motor recovery.

Stem/progenitor cell transplantation delivery of astrocytes is a potentially powerful strategy for spinal cord injury (SCI). Axon extension into SCI lesions that occur spontaneously or in response to experimental manipulations is often observed along endogenous astrocyte "bridges," suggesting that augmenting this response via astrocyte lineage transplantation can enhance axon regrowth. Given the importance of respiratory dysfunction post-SCI, we transplanted glial-restricted precursors (GRPs)-a class of lineage-restricted astrocyte progenitors-into the C2 hemisection model and evaluated effects on diaphragm function and the growth response of descending rostral ventral respiratory group (rVRG) axons that innervate phrenic motor neurons (PhMNs). GRPs survived long term and efficiently differentiated into astrocytes in injured spinal cord. GRPs promoted significant recovery of diaphragm electromyography amplitudes and stimulated robust regeneration of injured rVRG axons. Although rVRG fibers extended across the lesion, no regrowing axons re-entered caudal spinal cord to reinnervate PhMNs, suggesting that this regeneration response-although impressive-was not responsible for recovery. Within ipsilateral C3-5 ventral horn (PhMN location), GRPs induced substantial sprouting of spared fibers originating in contralateral rVRG and 5-HT axons that are important for regulating PhMN excitability; this sprouting was likely involved in functional effects of GRPs. Finally, GRPs reduced the macrophage response (which plays a key role in inducing axon retraction and limiting regrowth) both within the hemisection and at intact caudal spinal cord surrounding PhMNs. These findings demonstrate that astrocyte progenitor transplantation promotes significant plasticity of rVRG-PhMN circuitry and restoration of diaphragm function and suggest that these effects may be in part through immunomodulation., National Institute of Neurological Disorders and Stroke. Grant Number: 2R01NS079702‐06 (to A.C.L.) Paralyzed Veterans of America Research Foundation. Grant Numbers: Grant 476686 (to A.C.L), 476686 NINDS. Grant Number: 2R01NS079702‐06

Automatic Speech Recognition is a procedure for recognizing normal human speech automatically with better accuracy and to generate a sequence of words. Throughout the previous couple of decades it holds an active field of research. This paper summarizes a short overview on Automatic Speech Recognition, it’s recent progress and the technology used for it. There are various different types of Speech Recognition methods and this paper aimed at summarizing those methods.

Damage to respiratory neural circuitry and consequent loss of diaphragm function is a major cause of morbidity and mortality in individuals suffering from traumatic cervical spinal cord injury (SCI). Repair of CNS axons after SCI remains a therapeutic challenge, despite current efforts. SCI disrupts inspiratory signals originating in the rostral ventral respiratory group (rVRG) of the medulla from their phrenic motor neuron (PhMN) targets, resulting in loss of diaphragm function. Using a rat model of cervical hemisection SCI, we aimed to restore rVRG-PhMN-diaphragm circuitry by stimulating regeneration of injured rVRG axons via targeted induction of Rheb (ras homolog enriched in brain), a signaling molecule that regulates neuronal-intrinsic axon growth potential. Following C2 hemisection, we performed intra-rVRG injection of an adeno-associated virus serotype-2 (AAV2) vector that drives expression of a constitutively-active form of Rheb (cRheb). rVRG neuron-specific cRheb expression robustly increased mTOR pathway activity within the transduced rVRG neuron population ipsilateral to the hemisection, as assessed by levels of phosphorylated ribosomal S6 kinase. By co-injecting our novel AAV2-mCherry/WGA anterograde/trans-synaptic axonal tracer into rVRG, we found that cRheb expression promoted regeneration of injured rVRG axons into the lesion site, while we observed no rVRG axon regrowth with AAV2-GFP control. AAV2-cRheb also significantly reduced rVRG axonal dieback within the intact spinal cord rostral to the lesion. However, cRheb expression did not promote any recovery of ipsilateral hemi-diaphragm function, as assessed by inspiratory electromyography (EMG) burst amplitudes. This lack of functional recovery was likely because regrowing rVRG fibers did not extend back into the caudal spinal cord to synaptically reinnervate PhMNs that we retrogradely-labeled with cholera toxin B from the ipsilateral hemi-diaphragm. Our findings demonstrate that enhancing neuronal-intrinsic axon growth capacity can promote regeneration of injured bulbospinal respiratory axons after SCI, but this strategy may need to be combined with other manipulations to achieve reconnection of damaged neural circuitry and ultimately recovery of diaphragm function.

Downregulation in the astroglial glutamate transporter EAAT2 in amyotrophic lateral sclerosis (ALS) patients and mutant SOD1 mouse models of ALS is believed to contribute to the death of motor neurons by excitotoxicity. We previously reported that caspase-3 cleaves EAAT2 at a unique cleavage consensus site located in its c-terminus domain, a proteolytic cleavage that also occurs in vivo in the mutant SOD1 mouse model of ALS and leads to accumulation of a sumoylated EAAT2 C-terminus fragment (CTE-SUMO1) beginning around onset of disease. CTE-SUMO1 accumulates in PML nuclear bodies of astrocytes and causes them to alter their mature phenotypes and secrete factors toxic to motor neurons. Here, we report that mutating the caspase-3 consensus site in the EAAT2 sequence with an aspartate to asparagine mutation (D504N), thereby inhibiting caspase-3 cleavage of EAAT2, confers protection to the SOD1-G93A mouse. EAAT2-D504N knock-in mutant mice were generated and crossed with SOD1-G93A mice to assess the in vivo pathogenic relevance for ALS symptoms of EAAT2 cleavage. The mutation did not affect normal EAAT2 function nor non-ALS mice. In agreement with the timing of CTE-SUMO1 accumulation, while onset of disease was not affected, the mutation caused an extension in progression time, a delay in the development of hindlimb and forelimb muscle weakness, and a significant increase in the lifespan of SOD1-G93A mice.

Objective To examine the characteristics of auditory verbal hallucinations and associated factors in older adults with schizophrenia. Methods One hundred ninety-eight persons aged 55 and older living in the community who had developed schizophrenia before age 45 years were assessed for the presence, topography, content, and subjective qualities of auditory hallucinations. George's social antecedent model of psychopathology was used to examine 17 predictor variables of auditory hallucinations. Results Thirty-two percent experienced auditory verbal hallucinations. More than half heard voices daily, heard good/pleasant voices, or had command hallucinations; 25% obeyed "bad" voices, whereas 87% obeyed "good" voices. There were no significant differences in depression and social functioning between persons judging their voices to be good versus bad. In logistic regression analysis, depressive symptoms, Positive and Negative Syndrome Scale delusion score (>2), and male gender were associated with auditory verbal hallucinations. Conclusion Older adults with schizophrenia had a lower rate of auditory verbal hallucinations than had been reported previously for younger persons with schizophrenia. For most features of auditory verbal hallucinations, older adults had similar rates to younger persons. However, older adults were more apt to judge their voices as good and more likely to obey the good voices than those voices perceived as bad. From a clinical standpoint, this may be construed as a potentially useful coping strategy. However, subjective judgments about voices did not significantly affect mood or functioning, and the presence of auditory verbal hallucinations was associated with more depressive symptoms.

Parkinson's disease (PD) represents a challenging condition where different therapeutic options have evolved over the course of the last 50 years. The potential for therapeutic use of cell transplantation for cell replacement or for gene delivery of neurotrophic factors has received a great deal of attention. Currently, all available treatment options are directed towards the amelioration of symptoms. A greater understanding of the distinctive pathology underlying PD might offer some novel therapeutic approaches. Transplantation of embryonic ventral mesencephalon (VM) dopaminergic neurons has shown promise in animal studies, but similar transplant procedures have shown limited success in clinical trials. One important issue may be the site of transplantation. Previous studies have transplanted VM into the striatum, which is the target of these neurons. With increased understanding of growth and guidance molecule effecting dopaminergic neurons, it may be feasible to place transplants in the damaged substantia nigra and direct the growth of axons into target regions to reconstruction of midbrain dopamine (DA) circuitry. Our established and on-going understanding of the molecular cues which support directed growth of DA neurons form an important basis for the refinement and optimization of VM grafting procedures, and also the development of new procedures based on the use of stem cells. In this review, we discuss transplantation therapy and how selective guidance molecules could be used to reconstruction of nigrostriatal circuit.

Different experimental and clinical strategies have been used to promote survival of transplanted embryonic ventral mesencephalic (VM) neurons. However, few studies have focused on the long-distance growth of dopaminergic axons from VM transplants. The aim of this study is to identify some of the growth and guidance factors that support directed long-distance growth of dopaminergic axons from VM transplants. Lentivirus encoding either glial cell line-derived neurotrophic factor (GDNF) or netrin-1, or a combination of lenti-GDNF with either lenti-GDNF family receptor α1 (GFRα-1) or lenti-netrin-1 was injected to form a gradient along the corpus callosum. Two weeks later, a piece of embryonic day 14 VM tissue was transplanted into the corpus callosum adjacent to the low end of the gradient. Results showed that tyrosine hydroxylase (TH(+)) axons grew a very short distance from the VM transplants in control groups, with few axons reaching the midline. In GDNF or netrin-1 expressing groups, more TH(+) axons grew out of transplants and reached the midline. Pathways co-expressing GDNF with either GFRα-1 or netrin-1 showed significantly increased axonal outgrowth. Interestingly, only the GDNF/netrin-1 combination resulted in the majority of axons reaching the distal target (80%), whereas along the GDNF/GFRα-1 pathway only 20% of the axons leaving the transplant reached the distal target. This technique of long-distance axon guidance may prove to be a useful strategy in reconstructing damaged neuronal circuits, such as the nigrostriatal pathway in Parkinson's disease.

We have recently reported that α2β1 and α1β1 isozymes of Na+/K+-ATPase (NKA) are localized in the caveolae whereas only the α1β1 isozyme of NKA is localized in the non-caveolae fraction of pulmonary artery smooth muscle cell membrane. It is well known that different isoforms of NKA are regulated differentially by PKA and PKC, but the mechanism is not known in the caveolae of pulmonary artery smooth muscle cells. Herein, we examined whether this regulation occurs through phospholemman (PLM) in the caveolae. Our results suggest that PKC mediated phosphorylation of PLM occurs only when it is associated with the α2 isoform of NKA, whereas phosphorylation of PLM by PKA occurs when it is associated with the α1 isoform of NKA. To investigate the mechanism of regulation of α2 isoform of NKA by PKC-mediated phosphorylation of PLM, we have purified PLM from the caveolae and reconstituted into the liposomes. Our result revealed that (i) in the reconstituted liposomes phosphorylated PLM (PKC mediated) stimulate NKA activity, which appears to be due to an increase in the turnover number of the enzyme; (ii) phosphorylated PLM did not change the affinity of the pump for Na+; and (iii) even after phosphorylation by PKC, PLM still remains associated with the α2 isoform of NKA.

Aims We sought to identify, purify and partially characterize a protein inhibitor of Na + /K + -ATPase in cytosol of pulmonary artery smooth muscle. Main methods (i) By spectrophotometric assay, we identified an inhibitor of Na + /K + -ATPase in cytosolic fraction of pulmonary artery smooth muscle; (ii) the inhibitor was purified by a combination of ammonium sulfate precipitation, diethylaminoethyl (DEAE) cellulose chromatography, hydroxyapatite chromatography and gel filtration chromatography; (iii) additionally, we have also purified Na + /K + -ATPase α 2 β 1 and α 1 β 1 isozymes for determining some characteristics of the inhibitor. Key findings We identified a novel endogenous protein inhibitor of Na + /K + -ATPase having an apparent mol mass of ∼ 70 kDa in the cytosolic fraction of the smooth muscle. The IC 50 value of the inhibitor towards the enzyme was determined to be in the nanomolar range. Important characteristics of the inhibitor are as follows: (i) it showed different affinities toward the α 2 β 1 and α 1 β 1 isozymes of the Na + /K + -ATPase; (ii) it interacted reversibly to the E 1 site of the enzyme; (iii) the inhibitor blocked the phosphorylated intermediate formation; and (iv) it competitively inhibited the enzyme with respect to ATP. CD studies indicated that the inhibitor causes an alteration of the conformation of the enzyme. The inhibition study also suggested that the DHPC solubilized Na + /K + -ATPase exists as (αβ) 2 diprotomer. Significance The inhibitor binds to the Na + /K + -ATPase at a site different from the ouabain binding site. The novelty of the inhibitor is that it acts in an isoform specific manner on the enzyme, where α 2 is more sensitive than α 1 .

The plasma membrane Ca2+ATPase (PMCA) plays a major role in clearing Ca2+from the neuronal cytoplasm. The cytoplasmic Ca2+clearance rate affects neuronal excitability, synaptic plasticity, and neurotransmission. Here, we examined the modulation of PMCA activity by PTKs in hippocampal neurons. PMCA-mediated Ca2+clearance slowed in the presence of pyrazolopyrimidine 2, an inhibitor of Src family kinases (SFKs), and accelerated in the presence of C2-ceramide, an activator of PTKs. Ca2+clearance kinetics were attenuated in cells expressing a dominant-negative Src mutant, suggesting that the pump is tonically stimulated by a PTK. Tonic stimulation was reduced in hippocampal neurons expressing short hairpin (sh)RNA directed to mRNA for Yes. shRNA-mediated knockdown of PMCA isoform 1 (PMCA1) removed tonic stimulation of Ca2+clearance, indicating that the kinase stimulates PMCA1. IL-1β accelerated Ca2+clearance in a manner blocked by an IL-1β receptor antagonist or by an inhibitor of neutral sphingomyelinase, the enzyme that produces ceramide. Thus IL-1β activates an SFK to stimulate the plasma membrane Ca2+pump, decreasing the duration of Ca2+transients in hippocampal neurons.

The Na+/K+-ATPase is a membrane bound P-type ATPase that exchanges Na+ and K+ ions across the plasma membrane in expense of ATP hydrolysis. It maintains for electrical excitability, neurotransmitter transport, volume regulation, and other vital cellular functions. The four isoforms of the Na+/K+-ATPase α-subunit have a cell-specific and developmentally regulated expression pattern. There are different isoforms of the Na+/K+-ATPase expressed in neurons and glial cells. Alterations of Na+/K+-ATPase activity due to global loss or isoform specific mutational effect are evident in different neurological disorders. Mutations in the ATP1A3 gene which encodes Na+/K+-ATPase α3 subunits, cause Rapid-Onset of Dystonia Parkinsonism (RDP), a rare movement disorder characterized by sudden onset of dystonic spasms and slowness of movement. It is evident that Na+/K+-ATPase α2 subunits are upregulated in spinal cord of sporadic and familial amyotrophic lateral sclerosis (ALS) patients. The α2-Na+/K+-ATPases are also enriched in astrocytes expressing mutant superoxide dismutase 1 (SOD1), which causes familial ALS. Here we focused to understand the physiological and molecular fundamentals associated with dysfunction of Na+/K+-ATPase in RDP and ALS.

Na+/K+-ATPase (NKA), a transmembrane protein, facilitates active transport of three Na+ out of the cell and two K+ into the cell with the expense of an ATP. It plays an important role in regulating the ionic homeostasis and maintaining membrane potential. Additionally, NKA plays a crucial role in driving a variety of secondary transport processes such as Na+-dependent glucose and amino acid transport.

Treatment of microsomes (preferentially enriched with endoplasmic reticulum) isolated from bovine pulmonary artery smooth muscle tissue with H2O2 (1 mM) markedly stimulated matrix metalloproteinase activity and also inhibited Na+ dependent Ca2+ uptake. Electron micrograph revealed that H2O2 (1 mM) does not cause any damage to the microsomes. MMP-2 and TIMP-2 were determined to be the ambient protease and corresponding antiprotease of the microsomes. Pretreatment with vitamin E (1 mM) and TIMP-2 (50 μg/ml) reversed the effect produced by H2O2 (1 mM) on Na+ dependent Ca2+ uptake in the microsomes. However, H2O2 (1 mM) caused changes in MMP-2 activity and Na+ dependent Ca2+ uptake were not reversed upon pretreatment of the microsomes with a low concentration of 5 μg/ml of TIMP-2 which otherwise reversed MMP-2 (1 μg/ml) mediated increase in 14C-gelatin degradation and inhibition of Na+ dependent Ca2+ uptake. Combined treatment of the microsomes with a low dose of MMP-2 (0.5 μg/ml) and H2O2 (0.5 mM) inhibited Na+ dependent Ca2+ uptake in the microsomes compared to the respective low dose of either of them. Direct treatment of TIMP-2 (5 μg/ml) with H2O2 (1 mM) abolished the inhibitory effect of the inhibitor on 14C-gelatinolytic activity elicited by 1 μg/ml of MMP-2. Thus, one of the mechanisms by which H2O2 activates MMP-2 could be due to inactivation of TIMP-2 by the oxidant. The resulting activation of MMP-2 subsequently inhibits Na+ dependent Ca2+ uptake in the microsomes. (Mol Cell Biochem 270: 79–87, 2005)

Treatment of microsomes (preferably enriched with endoplasmic reticulum) isolated from bovine pulmonary artery smooth muscle tissue with the O2*- -generating system (hypoxanthine (HPX) plus xanthine oxidase (XO)), markedly stimulated matrix metalloproteinase-2 (MMP-2) activity and also enhanced Ca2+ ATPase activity and ATP-dependent Ca2+ uptake. Pretreatment with superoxide dismutase (SOD) and tissue inhibitor of metalloproteinase (TIMP-2) (50 microg ml(-1)), preserved the increase in MMP-2 activity, Ca2+ ATPase activity and also ATP-dependent Ca2+ uptake in the microsomes. In contrast, Na+-dependent Ca2+ uptake in the microsomes was found to be inhibited by the O2*- - generating system. Additionally, O2*- -induced inhibition of Na+-dependent Ca2+ uptake was reversed by SOD and TIMP-2 (50 microg ml(-1)). Electron microscopy revealed that treatment with the O2*- -generating system did not cause any noticeable damage to the microsomes. O2*- -induced changes in MMP-2 activity, ATP-dependent Ca2+ uptake and Na+-dependent Ca2+ uptake, were not reversed upon pretreatment of the microsomes with a low dose (5 microg ml(-1)) of TIMP-2 which, on the contrary, reversed MMP-2 (1 microg ml(-1))-mediated alteration on these parameters. The inhibition of Na+-dependent Ca2+ uptake by O2*- and MMP-2, overpowered the stimulation of ATP-dependent Ca2+ uptake in the microsomes. Treatment of TIMP-2 (5 microg ml(-1)) with the O2*- -generating system abolished the inhibitory effect of TIMP-2 (5 microg ml(-1)) on MMP-2 (1 microg ml(-1)) (measured by (14)C-gelatin degradation). Overall, the present study suggests that O2*- inactivated TIMP-2, the ambient inhibitor of MMP-2, leading to activation of the ambient proteinase, MMP-2, which subsequently stimulated Ca2+ ATPase activity and ATP-dependent Ca2+ uptake, but inhibited Na+-dependent Ca2+ uptake, resulting in a marked decrease in Ca2+ uptake in the smooth muscle microsomes.

Treatment of bovine pulmonary artery smooth muscle microsomes with tert-butylhydroperoxide (t-buOOH) (300 microM) markedly stimulated matrix metalloproteinase-2 (MMP-2) activity and enhanced Ca(2+)-ATPase activity and ATP-dependent Ca2+ uptake. Pre-treatment with vit. E (1 mM) and tissue inhibitor of metalloproteinase-2 (TIMP-2) (50 microg/ml) prevented t-buOOH-induced stimulation of MMP-2 activity, Ca(2+)-ATPase activity and ATP-dependent Ca2+ uptake. In contrast, Na(+)-dependent Ca2+ uptake was inhibited by t-buOOH and the inhibition was reversed by vit. E (1 mM) and TIMP-2 (50 microg/ml). However, t-buOOH-triggered changes in MMP-2 activity, and ATP- and Na(+)-dependent Ca2+ uptake were not reversed upon pre-treatment of the microsomes with a low concentration of 5 microg/ml of TIMP-2, which on the contrary reversed MMP-2 (1 microg/ml)-mediated alteration on these parameters. The inhibition of Na(+)-dependent Ca2+ uptake by MMP-2 under t-buOOH treatment overpowered the stimulation of ATP-dependent Ca2+ uptake in the microsomes. Combined treatment of the microsomes with low doses of MMP-2 (0.5 microg/ml) and t-buOOH (100 microM) augmented Ca(2+)-ATPase activity and ATP-dependent Ca2+ uptake, but inhibited Na(+)-dependent Ca2+ uptake, compared to that elicited by either MMP-2 (0.5 microg/ml) or t-buOOH (100 microM). Pre-treatment with TIMP-2 (50 microg/ml) reversed the effects of MMP-2 (0.5 microg/ml) and/or t-buOOH (100 microM). Although pre-treatment with 5 microg/ml of TIMP-2 reversed the effects produced by MMP-2 (0.5 microg/ml), but it did not inhibit the responses elicited by t-buOOH (300 microM) or t-buOOH (100 microM) plus MMP-2 (0.5 microg/ml) in the microsomes. Treatment with TIMP-2 (5 microg/ml) inhibited MMP-2 (1 microg/ml) activity (assessed by [14C]-gelatin degradation), whereas treatment of t-buOOH (300 microM) with TIMP-2 (5 microg/ml) abolished the inhibitory effect of TIMP-2 (5 microg/ml) on MMP-2 (1 microg/ml) activity (assessed by [14C]-gelatin degradation). Overall, these results suggested that t-buOOH inactivated TIMP-2, the ambient inhibitor of MMP-2, leading to activation of the ambient proteinase, MMP-2 which subsequently stimulated Ca(2+)-ATPase activity and ATP-dependent Ca2+ uptake, but inhibited Na(+)-dependent Ca2+ uptake, resulting in a marked decrease in Ca2+ uptake in the microsomes.

Tourism, world’s most significant revenue earning sector, is highly dependent on the effectiveness of the tourism website. A tourist destination must have a website enriched with different design and service related attributes. Here, a user feedback based study was conducted. This user feedback based study shows that there is a lot of difference between the appeal of Indian and International tourism websites. A fuzzy score has been obtained to assign ranks to the websites on the basis of user feedback. On the other hand, ranks were given to the same set of websites on the basis of simple presence and absence of attributes. Websites having more presence of attributes were given higher ranks. The presence and absence of attributes were judged from simple observation. Then it was observed that there is a high degree of correlation between the ranks obtained from the two methods. This shows that more presence of attributes gives better user feedback and an increase in the number of design and service related attributes which is required for Indian tourism websites. In this way, Indian tourism websites can give better impact on user’s mind. Key words: Effectiveness, tourist.

We have recently reported that α(2)β(1) and α(1)β(1) isozymes of Na(+)/K(+)-ATPase (NKA) are localized in the caveolae whereas only the α(1)β(1) isozyme of NKA is localized in the non-caveolae fraction of pulmonary artery smooth muscle cell membrane. It is well known that different isoforms of NKA are regulated differentially by PKA and PKC, but the mechanism is not known in the caveolae of pulmonary artery smooth muscle cells. Herein, we examined whether this regulation occurs through phospholemman (PLM) in the caveolae. Our results suggest that PKC mediated phosphorylation of PLM occurs only when it is associated with the α(2) isoform of NKA, whereas phosphorylation of PLM by PKA occurs when it is associated with the α(1) isoform of NKA. To investigate the mechanism of regulation of α(2) isoform of NKA by PKC-mediated phosphorylation of PLM, we have purified PLM from the caveolae and reconstituted into the liposomes. Our result revealed that (i) in the reconstituted liposomes phosphorylated PLM (PKC mediated) stimulate NKA activity, which appears to be due to an increase in the turnover number of the enzyme; (ii) phosphorylated PLM did not change the affinity of the pump for Na(+); and (iii) even after phosphorylation by PKC, PLM still remains associated with the α(2) isoform of NKA.

The cytoplasmic Ca2+clearance rate affects neuronal excitability, plasticity, and synaptic transmission. Here, we examined the modulation of the plasma membrane Ca2+ATPase (PMCA) by tyrosine kinases. In rat sensory neurons grown in culture, the PMCA was under tonic inhibition by a member of the Src family of tyrosine kinases (SFKs). Ca2+clearance accelerated in the presence of selective tyrosine kinase inhibitors. Tonic inhibition of the PMCA was attenuated in cells expressing a dominant-negative construct or shRNA directed to message for the SFKs Lck or Fyn, but not Src. SFKs did not appear to phosphorylate the PMCA directly but instead activated focal adhesion kinase (FAK). Expression of constitutively active FAK enhanced and dominant-negative or shRNA knockdown of FAK attenuated tonic inhibition. Antisense knockdown of PMCA isoform 4 removed tonic inhibition of Ca2+clearance, indicating that FAK acts on PMCA4. The hyaluronan receptor CD44 activates SFK-FAK signaling cascades and is expressed in sensory neurons. Treating neurons with a CD44-blocking antibody or short hyaluronan oligosaccharides, which are produced during injury and displace macromolecular hyaluronan from CD44, attenuated tonic PMCA inhibition. Ca2+-activated K+channels mediate a slow afterhyperpolarization in sensory neurons that was inhibited by tyrosine kinase inhibitors and enhanced by knockdown of PMCA4. Thus, we describe a novel kinase cascade in sensory neurons that enables the extracellular matrix to alter Ca2+signals by modulating PMCA-mediated Ca2+clearance. This signaling pathway may influence the excitability of sensory neurons following injury.

We identified alpha(2), alpha(1), and beta(1) isoforms of Na(+)/K(+)-ATPase in caveolae vesicles of bovine pulmonary smooth muscle plasma membrane. The biochemical and biophysical characteristics of the alpha(2)beta(1) isozyme of Na(+)/K(+)-ATPase from caveolae vesicles were studied during solubilization and purification using the detergents 1,2-heptanoyl-sn-phosphatidylcholine (DHPC), poly(oxy-ethylene)8-lauryl ether (C(12)E(8)), and Triton X-100, and reconstitution with the phospholipid dioleoyl-phosphatidylcholine (DOPC). DHPC was determined to be superior to C(12)E(8), whereas C(12)E(8) was better than Triton X-100 in the active enzyme yields and specific activity. Fluorescence studies with DHPC-purified alpha(2)beta(1) isozyme of Na(+)/K(+)-ATPase elicited higher E1Na-E2 K transition compared with that of the C(12)E(8)- and Triton X-100-purified enzyme. The rate of Na(+) efflux in DHPC-DOPC-reconstituted isozyme was higher compared to the C(12)E(8)-DOPC- and Triton X100-DOPC-reconstituted enzyme. Circular dichroism analysis suggests that the DHPC-purified alpha(2)beta(1) isozyme of Na(+)/K(+)-ATPase possessed more organized secondary structure compared to the C(12)E(8)- and Triton X-100-purified isozyme.

Aims We sought to determine the mechanisms of an increase in Ca 2+ level in caveolae vesicles in pulmonary smooth muscle plasma membrane during Na + /K + -ATPase inhibition by ouabain. Main methods The caveolae vesicles isolated by density gradient centrifugation were characterized by electron microscopic and immunologic studies and determined ouabain induced increase in Na + and Ca 2+ levels in the vesicles with fluorescent probes, SBFI-AM and Fura2-AM, respectively. Key findings We identified the α 2 β 1 and α 1 β 1 isozymes of Na + /K + -ATPase in caveolae vesicles, and only the α 1 β 1 isozyme in noncaveolae fraction of the plasma membrane. The α 2 -isoform contributes solely to the enzyme inhibition in the caveolae vesicles at 40 nM ouabain. Methylisobutylamiloride (Na + /H + -exchange inhibitor) and tetrodotoxin (voltage-gated Na + -channel inhibitor) pretreatment prevented ouabain induced increase in Na + and Ca 2+ levels. Ouabain induced increase in Ca 2+ level was markedly, but not completely, inhibited by KB-R7943 (reverse-mode Na + /Ca 2+ -exchange inhibitor) and verapamil (L-type Ca 2+ -channel inhibitor). However, pretreatment with tetrodotoxin in conjunction with KB-R7943 and verapamil blunted ouabain induced increase in Ca 2+ level in the caveolae vesicles, indicating that apart from Na + /Ca + -exchanger and L-type Ca 2+ -channels, “slip-mode conductance” of Na + channels could also be involved in this scenario. Significance Inhibition of α 2 isoform of Na + /K + -ATPase by ouabain plays a crucial role in modulating the Ca 2+ influx regulatory components in the caveolae microdomain for marked increase in (Ca 2+ ) i in the smooth muscle, which could be important for the manifestation of pulmonary hypertension.

Calpain and calpastatin have been demonstrated to play many physiological roles in a variety of systems. It, therefore, appears important to study their localization and association in different suborganelles. Using immunoblot studies, we have identified 80 kDa m-calpain in both lumen and membrane of ER isolated from bovine pulmonary artery smooth muscle. Treatment of the ER with Na(2)CO(3) and proteinase K demonstrated that 80 kDa catalytic subunit and 28 kDa regulatory subunit (Rs) of m-calpain, and the 110-kDa and 70-kDa calpastatin (Cs) forms are localized in the cytosolic side of the ER membrane. Coimmunoprecipitation studies revealed that m-calpain is associated with calpastatin in the cytosolic face of the ER membrane. We have also identified m-calpain activity both in the ER membrane and lumen by casein-zymography. The casein-zymogram has also been utilized to demonstrate differential pattern of the effects of reversible and irreversible cysteine protease inhibitors on m-calpain activity. Thus, a potential site of Cs regulation of m-calpain activity is created by positioning Cs, 80 kDa and 28 kDa m-calpain in the cytosolic face of ER membrane. However, such is not the case for the 80-kDa m-calpain found within the lumen of the ER because of the conspicuous absence of 28 kDa Rs of m-calpain and Cs in this locale.

Ca(2+) is a major intracellular messenger and nature has evolved multiple mechanisms to regulate free intracellular (Ca(2+))(i) level in situ. The Ca(2+) signal inducing contraction in cardiac muscle originates from two sources. Ca(2+) enters the cell through voltage dependent Ca(2+) channels. This Ca(2+) binds to and activates Ca(2+) release channels (ryanodine receptors) of the sarcoplasmic reticulum (SR) through a Ca(2+) induced Ca(2+) release (CICR) process. Entry of Ca(2+) with each contraction requires an equal amount of Ca(2+) extrusion within a single heartbeat to maintain Ca(2+) homeostasis and to ensure relaxation. Cardiac Ca(2+) extrusion mechanisms are mainly contributed by Na(+)/Ca(2+) exchanger and ATP dependent Ca(2+) pump (Ca(2+)-ATPase). These transport systems are important determinants of (Ca(2+))(i) level and cardiac contractility. Altered intracellular Ca(2+) handling importantly contributes to impaired contractility in heart failure. Chronic hyperactivity of the beta-adrenergic signaling pathway results in PKA-hyperphosphorylation of the cardiac RyR/intracellular Ca(2+) release channels. Numerous signaling molecules have been implicated in the development of hypertrophy and failure, including the beta-adrenergic receptor, protein kinase C, Gq, and the down stream effectors such as mitogen activated protein kinases pathways, and the Ca(2+) regulated phosphatase calcineurin. A number of signaling pathways have now been identified that may be key regulators of changes in myocardial structure and function in response to mutations in structural components of the cardiomyocytes. Myocardial structure and signal transduction are now merging into a common field of research that will lead to a more complete understanding of the molecular mechanisms that underlie heart diseases. Recent progress in molecular cardiology makes it possible to envision a new therapeutic approach to heart failure (HF), targeting key molecules involved in intracellular Ca(2+) handling such as RyR, SERCA2a, and PLN. Controlling these molecular functions by different agents have been found to be beneficial in some experimental conditions.

Treatment of microsomes (preferably enriched with endoplasmic reticulum) isolated from bovine pulmonary artery smooth muscle tissue with the O2*- -generating system (hypoxanthine (HPX) plus xanthine oxidase (XO)), markedly stimulated matrix metalloproteinase-2 (MMP-2) activity and also enhanced Ca2+ ATPase activity and ATP-dependent Ca2+ uptake. Pretreatment with superoxide dismutase (SOD) and tissue inhibitor of metalloproteinase (TIMP-2) (50 microg ml(-1)), preserved the increase in MMP-2 activity, Ca2+ ATPase activity and also ATP-dependent Ca2+ uptake in the microsomes. In contrast, Na+-dependent Ca2+ uptake in the microsomes was found to be inhibited by the O2*- - generating system. Additionally, O2*- -induced inhibition of Na+-dependent Ca2+ uptake was reversed by SOD and TIMP-2 (50 microg ml(-1)). Electron microscopy revealed that treatment with the O2*- -generating system did not cause any noticeable damage to the microsomes. O2*- -induced changes in MMP-2 activity, ATP-dependent Ca2+ uptake and Na+-dependent Ca2+ uptake, were not reversed upon pretreatment of the microsomes with a low dose (5 microg ml(-1)) of TIMP-2 which, on the contrary, reversed MMP-2 (1 microg ml(-1))-mediated alteration on these parameters. The inhibition of Na+-dependent Ca2+ uptake by O2*- and MMP-2, overpowered the stimulation of ATP-dependent Ca2+ uptake in the microsomes. Treatment of TIMP-2 (5 microg ml(-1)) with the O2*- -generating system abolished the inhibitory effect of TIMP-2 (5 microg ml(-1)) on MMP-2 (1 microg ml(-1)) (measured by (14)C-gelatin degradation). Overall, the present study suggests that O2*- inactivated TIMP-2, the ambient inhibitor of MMP-2, leading to activation of the ambient proteinase, MMP-2, which subsequently stimulated Ca2+ ATPase activity and ATP-dependent Ca2+ uptake, but inhibited Na+-dependent Ca2+ uptake, resulting in a marked decrease in Ca2+ uptake in the smooth muscle microsomes.

Introduction: There are little data available on the prevalence, course, associated factors, and impact of hallucinations in later life. This longitudinal study of older persons with schizophrenia explores: (1) the changes in the prevalence of hallucinations over time; (2) clinical and social variables at baseline that predict hallucinations on follow-up; (3) the effect of baseline hallucinations on various clinical and social outcomes; (4) variables associated with changes in hallucination status. Methods: The study consisted of 254 persons with schizophrenia spectrum disorders aged 55 and over living in NYC who developed the disorder prior to age 45. Data on 103 patients followed for a mean of 52 months are presented. Mean age was 61 years, 55% were male, and 55% were white. Hallucinations consisted self-reported auditory, visual, or olfactory symptoms. Results: There was no significant difference between the means of the PANSS hallucination scale at Time 1 (T1; 2.0 1.6) and Time 2 (T2; 1.8 1.5) and 33% and 26% of subjects had hallucinations at T1 and T2, respectively. None of these differences were significant. Notably, only 16% had hallucinations at both T1 and T2, 57% never had hallucinations, 10% developed hallucinations, and 17% no longer had hallucinations. Although several T1 variables predicted presence of T2 hallucinations, in logistic regression only the presence of hallucinations (OR1⁄45.8) and lower Community Integration Scale (OR1⁄4.60) scores at T1 remained significant predictors. The presence of hallucinations at T1 did not significantly correlate with any clinical variables at T2. Change from hallucinations at T1 to no hallucinations at T2 was associated with having higher Community Integration Scale scores and more confidantes at T1. Conclusions: Although point-prevalence of hallucinations is fairly low (less than one-third) there were fluctuations in symptoms so that 43% had hallucinations during the study period. There were few long-term predictors of hallucinations, although persons who had better community integration—a measure of independent living, life quality, and social engagement—had better outcomes. The findings suggest that hallucinations do not remain stable in later life, and commonly may disappear or re-emerge. Identifying age appropriate strategies for enhancing community integration may help maintain and increase the likelihood of symptom remission.