Development of prospective hospital-based venous thromboembolism registry across India: a study protocol

INTRODUCTION

Indian Council of Medical Research (ICMR), New Delhi has established a nationwide registry 'Indian Registry for Venous Thromoembolism Disorder (i-RegVeD)' for real-time analytics of sociodemographic profile of patients, disease patterns, management strategies, treatment choices and outcomes of patients with venous thromboemobolism (VTE). The purpose is to generate evidence on VTE in order to fill the gaps in the knowledge of the disease across various demographic regions.

METHODS AND ANALYSIS

This prospective hospital-based registry will be a continuous data collection process on the occurrence and characteristics of VTE from the 16 hospital sites pan India. This process would include obtaining clinical profiles, risk factors, diagnostic tests, treatment and outcome information of patients collected from medical records through an active method of data abstraction and data capture mechanism guided by an online web-based tool.

ETHICS AND DISSEMINATION

At centralised programme management unit, the study protocol was approved by the Institutional Ethics Committees (IEC) named ICMR-Central Ethics Committee on Human Research and similarly each of the participating site has obtained the ethical approval by their respective IECs. The results from this study will be disseminated publicly on the study website (https://iregved.icmr.org.in) as well as through scientific meetings and publications.

Autophagy is a novel pathway for neurofilament protein degradation in vivo

How macroautophagy/autophagy influences neurofilament (NF) proteins in neurons, a frequent target in neurodegenerative diseases and injury, is not known. NFs in axons have exceptionally long half-lives in vivo enabling formation of large stable supporting networks, but they can be rapidly degraded during Wallerian degeneration initiated by a limited calpain cleavage. Here, we identify autophagy as a previously unrecognized pathway for NF subunit protein degradation that modulates constitutive and inducible NF turnover in vivo. Levels of NEFL/NF-L, NEFM/NF-M, and NEFH/NF-H subunits rise substantially in neuroblastoma (N2a) cells after blocking autophagy either with the phosphatidylinositol 3-kinase (PtdIns3K) inhibitor 3-methyladenine (3-MA), by depleting ATG5 expression with shRNA, or by using both treatments. In contrast, activating autophagy with rapamycin significantly lowers NF levels in N2a cells. In the mouse brain, NF subunit levels increase in vivo after intracerebroventricular infusion of 3-MA. Furthermore, using tomographic confocal microscopy, immunoelectron microscopy, and biochemical fractionation, we demonstrate the presence of NF proteins intra-lumenally within autophagosomes (APs), autolysosomes (ALs), and lysosomes (LYs). Our findings establish a prominent role for autophagy in NF proteolysis. Autophagy may regulate axon cytoskeleton size and responses of the NF cytoskeleton to injury and disease.

Lymphomatous Interstitial Nephritis Coexistent with Paraneoplastic Crescentic Membranoproliferative Glomerulonephritis in a Case of Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is a rare aggressive lymphoproliferative disorders (LPD) of B-cell lymphoma, which usually presents in advanced stages at initial diagnosis. Renal involvement in MCL is very rare, especially the combined presence of both glomerular and interstitial disease. We report on a patient with lymphomatous interstitial nephritis (LIN) coexistent with paraneoplastic crescentic membranoproliferative glomerulonephritis (MPGN), subsequently diagnosed to have disseminated MCL with bone marrow and lymph nodal infiltration. He was treated with rituximab-based chemotherapy and went into complete renal remission at 6-months of follow up.

Seeing beyond the gut: An unusual cause of massive hematemesis

We report the clinical details, imaging findings, and management of a 74-year-old male who had recurrent episodes of massive hematemesis secondary to rupture of a cavernous internal carotid artery (ICA) aneurysm. Ruptured ICA aneurysms may present with epistaxis. However, intracranial aneurysmal rupture with hematemesis as the presenting complaint has not been described previously in the literature. In this case report we describe the pathophysiology of cerebral aneurysm as a cause of hematemesis and its management.

Transgenic expression of a ratiometric autophagy probe specifically in neurons enables the interrogation of brain autophagy in vivo

Autophagy-lysosome pathway (ALP) disruption is considered pathogenic in multiple neurodegenerative diseases; however, current methods are inadequate to investigate macroautophagy/autophagy flux in brain in vivo and its therapeutic modulation. Here, we describe a novel autophagy reporter mouse (TRGL6) stably expressing a dual-fluorescence-tagged LC3 (tfLC3, mRFP-eGFP-LC3) by transgenesis selectively in neurons. The tfLC3 probe distributes widely in the central nervous system, including spinal cord. Expression levels were similar to endogenous LC3 and induced no detectable ALP changes. This ratiometric reporter registers differential pH-dependent changes in color as autophagosomes form, fuse with lysosomes, acidify, and degrade substrates within autolysosomes. We confirmed predicted changes in neuronal autophagy flux following specific experimental ALP perturbations. Furthermore, using a third fluorescence label in TRGL6 brains to identify lysosomes by immunocytochemistry, we validated a novel procedure to detect defective autolysosomal acidification in vivo. Thus, TRGL6 mice represent a unique tool to investigate in vivo ALP dynamics in specific neuron populations in relation to neurological diseases, aging, and disease modifying agents. Abbreviations: ACTB: actin, beta; AD: Alzheimer disease; AL: autolysosomes; ALP: autophagy-lysosome pathway; AP: autophagosome; APP: amyloid beta (Abeta) precursor protein; ATG5: autophagy related 5; ATG7: autophagy related 7; AV: autophagic vacuoles; CNS: central nervous system; CTSD: cathepsin D; CQ: chloroquine; DMEM: Dulbecco's modified Eagle's medium; GFP: green fluorescent protein; GABARAP: gamma-aminobutyric acid receptor associated protein; GABARAPL2/GATE16: gamma-aminobutyric acid (GABA) receptor-associated protein-like 2; ICC: immunocytochemistry; ICV: intra-cerebroventricular; LAMP2: lysosomal-associated membrane protein 2; Leup: leupeptin; LY: lysosomes; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; RBFOX3/NeuN: RNA binding protein, fox-1 homolog (C. elegans) 3; RFP: red fluorescent protein; RPS6KB1: ribosomal protein S6 kinase, polypeptide 1; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SQSTM1: sequestosome 1; tfLC3: mRFP-eGFP-LC3; TRGL6: Thy1 mRFP eGFP LC3-line 6; PCR: polymerase chain reaction; PD: Parkinson disease.

Collapsing Glomerulopathy Superimposed on Diabetic Nephropathy

Diabetic nephropathy (DN) is characterized by gradually progressive renal failure and proteinuria. Various types of nondiabetic kidney diseases may superimpose on DN, and affect the natural course, prognosis, and management. Collapsing glomerulopathy (CG) is a form of glomerular proliferative injury, characterized by rapid progression and associated with poor prognosis. CG may be idiopathic or secondary to other causes, and it has also been described with other forms of glomerular diseases. The association of CG with DN has not been reported widely. We report on a patient with DN who has undergone renal biopsy due to massive proteinuria and rapid loss of renal function. Renal biopsy was suggestive of CG superimposed on DN. He was treated conservatively, however, progressed to end-stage renal disease rapidly.

Neurofilament light interaction with GluN1 modulates neurotransmission and schizophrenia-associated behaviors

Neurofilament (NFL) proteins have recently been found to play unique roles in synapses. NFL is known to interact with the GluN1 subunit of N-methyl-D-aspartic acid (NMDAR) and be reduced in schizophrenia though functional consequences are unknown. Here we investigated whether the interaction of NFL with GluN1 modulates synaptic transmission and schizophrenia-associated behaviors. The interaction of NFL with GluN1 was assessed by means of molecular, pharmacological, electrophysiological, magnetic resonance spectroscopy (MRS), and schizophrenia-associated behavior analyses. NFL deficits cause an NMDAR hypofunction phenotype including abnormal hippocampal function, as seen in schizophrenia. NFL-/- deletion in mice reduces dendritic spines and GluN1 protein levels, elevates ubiquitin-dependent turnover of GluN1 and hippocampal glutamate measured by MRS, and depresses hippocampal long-term potentiation. NMDAR-related behaviors are also impaired, including pup retrieval, spatial and social memory, prepulse inhibition, night-time activity, and response to NMDAR antagonist, whereas motor deficits are minimal. Importantly, partially lowering NFL in NFL+/- mice to levels seen regionally in schizophrenia, induced similar but milder NMDAR-related synaptic and behavioral deficits. Our findings support an emerging view that central nervous system neurofilament subunits including NFL in the present report, serve distinctive, critical roles in synapses relevant to neuropsychiatric diseases.

Neurofilaments and Neurofilament Proteins in Health and Disease

SUMMARYNeurofilaments (NFs) are unique among tissue-specific classes of intermediate filaments (IFs) in being heteropolymers composed of four subunits (NF-L [neurofilament light]; NF-M [neurofilament middle]; NF-H [neurofilament heavy]; and α-internexin or peripherin), each having different domain structures and functions. Here, we review how NFs provide structural support for the highly asymmetric geometries of neurons and, especially, for the marked radial expansion of myelinated axons crucial for effective nerve conduction velocity. NFs in axons extensively cross-bridge and interconnect with other non-IF components of the cytoskeleton, including microtubules, actin filaments, and other fibrous cytoskeletal elements, to establish a regionally specialized network that undergoes exceptionally slow local turnover and serves as a docking platform to organize other organelles and proteins. We also discuss how a small pool of oligomeric and short filamentous precursors in the slow phase of axonal transport maintains this network. A complex pattern of phosphorylation and dephosphorylation events on each subunit modulates filament assembly, turnover, and organization within the axonal cytoskeleton. Multiple factors, and especially turnover rate, determine the size of the network, which can vary substantially along the axon. NF gene mutations cause several neuroaxonal disorders characterized by disrupted subunit assembly and NF aggregation. Additional NF alterations are associated with varied neuropsychiatric disorders. New evidence that subunits of NFs exist within postsynaptic terminal boutons and influence neurotransmission suggests how NF proteins might contribute to normal synaptic function and neuropsychiatric disease states.

Calpastatin inhibits motor neuron death and increases survival of hSOD1(G93A) mice

Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease with a poorly understood cause and no effective treatment. Given that calpains mediate neurodegeneration in other pathological states and are abnormally activated in ALS, we investigated the possible ameliorative effects of inhibiting calpain over-activation in hSOD1(G93A) transgenic (Tg) mice in vivo by neuron-specific over-expression of calpastatin (CAST), the highly selective endogenous inhibitor of calpains. Our data indicate that over-expression of CAST in hSOD1(G93A) mice, which lowered calpain activation to levels comparable to wild-type mice, inhibited the abnormal breakdown of cytoskeletal proteins (spectrin, MAP2 and neurofilaments), and ameliorated motor axon loss. Disease onset in hSOD1(G93A) /CAST mice compared to littermate hSOD1(G93A) mice is delayed, which accounts for their longer time of survival. We also find that neuronal over-expression of CAST in hSOD1(G93A) transgenic mice inhibited production of putative neurotoxic caspase-cleaved tau and activation of Cdk5, which have been implicated in neurodegeneration in ALS models, and also reduced the formation of SOD1 oligomers. Our data indicate that inhibition of calpain with CAST is neuroprotective in an ALS mouse model. CAST (encoding calpastatin) inhibits hyperactivated calpain to prevent motor neuron disease operating through a cascade of events as indicated in the schematic, with relevance to amyotrophic lateral sclerosis (ALS). We propose that over-expression of CAST in motor neurons of hSOD1(G93A) mice inhibits activation of CDK5, breakdown of cytoskeletal proteins (NFs, MAP2 and Tau) and regulatory molecules (Cam Kinase IV, Calcineurin A), and disease-causing proteins (TDP-43, α-Synuclein and Huntingtin) to prevent neuronal loss and delay neurological deficits. In our experiments, CAST could also inhibit cleavage of Bid, Bax, AIF to prevent mitochondrial, ER and lysosome-mediated cell death mechanisms. Similarly, CAST over-expression in neurons attenuated pathological effects of TDP-43, α-synuclein and Huntingtin. These results suggest a potential value of specific small molecule inhibitors of calpains in delaying the development of ALS. Read the Editorial Highlight for this article on page 140.

Asymbiotic in vitro seed propagation of Dendrobium

The ability to germinate orchids from seeds in vitro presents a useful and viable method for the propagation of valuable germplasm, maintaining the genetic heterogeneity inherent in seeds. Given the ornamental and medicinal importance of many species within the genus Dendrobium, this review explores in vitro techniques for their asymbiotic seed germination. The influence of abiotic factors (such as temperature and light), methods of sterilization, composition of basal media, and supplementation with organic additives and plant growth regulators are discussed in context to achieve successful seed germination, protocorm formation, and further seedling growth and development. This review provides both a basis for the selection of optimal conditions, and a platform for the discovery of better ones, that would allow the development of new protocols and the exploration of new hypotheses for germination and conservation of Dendrobium seeds and seedlings.

Neurofilament subunits are integral components of synapses and modulate neurotransmission and behavior in vivo

Synaptic roles for neurofilament (NF) proteins have rarely been considered. Here, we establish all four NF subunits as integral resident proteins of synapses. Compared with the population in axons, NF subunits isolated from synapses have distinctive stoichiometry and phosphorylation state, and respond differently to perturbations in vivo. Completely eliminating NF proteins from brain by genetically deleting three subunits (α-internexin, NFH and NFL) markedly depresses hippocampal long-term potentiation induction without detectably altering synapse morphology. Deletion of NFM in mice, but not the deletion of any other NF subunit, amplifies dopamine D1-receptor-mediated motor responses to cocaine while redistributing postsynaptic D1-receptors from endosomes to plasma membrane, consistent with a specific modulatory role of NFM in D1-receptor recycling. These results identify a distinct pool of synaptic NF subunits and establish their key role in neurotransmission in vivo, suggesting potential novel influences of NF proteins in psychiatric as well as neurological states.

Dissociation of Axonal Neurofilament Content from Its Transport Rate

The axonal cytoskeleton of neurofilament (NF) is a long-lived network of fibrous elements believed to be a stationary structure maintained by a small pool of transported cytoskeletal precursors. Accordingly, it may be predicted that NF content in axons can vary independently from the transport rate of NF. In the present report, we confirm this prediction by showing that human NFH transgenic mice and transgenic mice expressing human NFL Ser55 (Asp) develop nearly identical abnormal patterns of NF accumulation and distribution in association with opposite changes in NF slow transport rates. We also show that the rate of NF transport in wild-type mice remains constant along a length of the optic axon where NF content varies 3-fold. Moreover, knockout mice lacking NFH develop even more extreme (6-fold) proximal to distal variation in NF number, which is associated with a normal wild-type rate of NF transport. The independence of regional NF content and NF transport is consistent with previous evidence suggesting that the rate of incorporation of transported NF precursors into a metabolically stable stationary cytoskeletal network is the major determinant of axonal NF content, enabling the generation of the striking local variations in NF number seen along axons.

Symbiotic in vitro seed propagation of Dendrobium: fungal and bacterial partners and their influence on plant growth and development

The genus Dendrobium is one of the largest genera of the Orchidaceae Juss. family, although some of its members are the most threatened today. The reason why many species face a vulnerable or endangered status is primarily because of anthropogenic interference in natural habitats and commercial overexploitation. The development and application of modern techniques and strategies directed towards in vitro propagation of orchids not only increases their number but also provides a viable means to conserve plants in an artificial environment, both in vitro and ex vitro, thus providing material for reintroduction. Dendrobium seed germination and propagation are challenging processes in vivo and in vitro, especially when the extreme specialization of these plants is considered: (1) their biotic relationships with pollinators and mycorrhizae; (2) adaptation to epiphytic or lithophytic life-styles; (3) fine-scale requirements for an optimal combination of nutrients, light, temperature, and pH. This review also aims to summarize the available data on symbiotic in vitro Dendrobium seed germination. The influence of abiotic factors as well as composition and amounts of different exogenous nutrient substances is examined. With a view to better understanding how to optimize and control in vitro symbiotic associations, a part of the review describes the strong biotic relations of Dendrobium with different associative microorganisms that form microbial communities with adult plants, and also influence symbiotic seed germination. The beneficial role of plant growth-promoting bacteria is also discussed.

Oil spill experiment using airborne DLR ESAR off the coast of Diu, India

Oil spill experiment results in the coastal waters of Diu, India, with an airborne DLR ESAR sensor are discussed with reference to the SAR frequency, polarization and viewing angle. The SAR data acquired in the quad polarization of the L band and dual polarization of the C band over two spills are studied. A higher oil and water contrast is observed in the L-VV polarization than in the C-HH mode. Oil spill discrimination is possible over a wider view angle of the airborne SAR sensor data in L band than in C band. This study has also analyzed the spread and drift of oil in coastal waters.

Totally drug-resistant tuberculosis and adjunct therapies

The first cases of totally drug-resistant (TDR) tuberculosis (TB) were reported in Italy 10 years ago; more recently, cases have also been reported in Iran, India and South Africa. Although there is no consensus on terminology, it is most commonly described as 'resistance to all first- and second-line drugs used to treat TB'. Mycobacterium tuberculosis (M.tb) acquires drug resistance mutations in a sequential fashion under suboptimal drug pressure due to monotherapy, inadequate dosing, treatment interruptions and drug interactions. The treatment of TDR-TB includes antibiotics with disputed or minimal effectiveness against M.tb, and the fatality rate is high. Comorbidities such as diabetes and infection with human immunodeficiency virus further impact on TB treatment options and survival rates. Several new drug candidates with novel modes of action are under late-stage clinical evaluation (e.g., delamanid, bedaquiline, SQ109 and sutezolid). 'Repurposed' antibiotics have also recently been included in the treatment of extensively drug resistant TB. However, because of mutations in M.tb, drugs will not provide a cure for TB in the long term. Adjunct TB therapies, including therapeutic vaccines, vitamin supplementation and/or repurposing of drugs targeting biologically and clinically relevant molecular pathways, may achieve better clinical outcomes in combination with standard chemotherapy. Here, we review broader perspectives of drug resistance in TB and potential adjunct treatment options.

Calpain inhibition mediates autophagy-dependent protection against polyglutamine toxicity

Over recent years, accumulated evidence suggests that autophagy induction is protective in animal models of a number of neurodegenerative diseases. Intense research in the field has elucidated different pathways through which autophagy can be upregulated and it is important to establish how modulation of these pathways impacts upon disease progression in vivo and therefore which, if any, may have further therapeutic relevance. In addition, it is important to understand how alterations in these target pathways may affect normal physiology when constitutively modulated over a long time period, as would be required for treatment of neurodegenerative diseases. Here we evaluate the potential protective effect of downregulation of calpains. We demonstrate, in Drosophila, that calpain knockdown protects against the aggregation and toxicity of proteins, like mutant huntingtin, in an autophagy-dependent fashion. Furthermore, we demonstrate that, overexpression of the calpain inhibitor, calpastatin, increases autophagosome levels and is protective in a mouse model of Huntington's disease, improving motor signs and delaying the onset of tremors. Importantly, long-term inhibition of calpains did not result in any overt deleterious phenotypes in mice. Thus, calpain inhibition, or activation of autophagy pathways downstream of calpains, may be suitable therapeutic targets for diseases like Huntington's disease.

Overexpression of the calpain-specific inhibitor calpastatin reduces human alpha-Synuclein processing, aggregation and synaptic impairment in [A30P]αSyn transgenic mice

Lewy bodies, a pathological hallmark of Parkinson's disease (PD), contain aggregated alpha-synuclein (αSyn), which is found in several modified forms and can be discovered phosphorylated, ubiquitinated and truncated. Aggregation-prone truncated species of αSyn caused by aberrant cleavage of this fibrillogenic protein are hypothesized to participate in its sequestration into inclusions subsequently leading to synaptic dysfunction and neuronal death. Here, we investigated the role of calpain cleavage of αSyn in vivo by generating two opposing mouse models. We crossed into human [A30P]αSyn transgenic (i) mice deficient for calpastatin, a calpain-specific inhibitor, thus enhancing calpain activity (SynCAST(-)) and (ii) mice overexpressing human calpastatin leading to reduced calpain activity (SynCAST(+)). As anticipated, a reduced calpain activity led to a decreased number of αSyn-positive aggregates, whereas loss of calpastatin led to increased truncation of αSyn in SynCAST(-). Furthermore, overexpression of calpastatin decreased astrogliosis and the calpain-dependent degradation of synaptic proteins, potentially ameliorating the observed neuropathology in [A30P]αSyn and SynCAST(+) mice. Overall, our data further support a crucial role of calpains, particularly of calpain 1, in the pathogenesis of PD and in disease-associated aggregation of αSyn, indicating a therapeutic potential of calpain inhibition in PD.

The C-terminal domains of NF-H and NF-M subunits maintain axonal neurofilament content by blocking turnover of the stationary neurofilament network

Newly synthesized neurofilaments or protofilaments are incorporated into a highly stable stationary cytoskeleton network as they are transported along axons. Although the heavily phosphorylated carboxyl-terminal tail domains of the heavy and medium neurofilament (NF) subunits have been proposed to contribute to this process and particularly to stability of this structure, their function is still obscure. Here we show in NF-H/M tail deletion [NF-(H/M)(tailΔ)] mice that the deletion of both of these domains selectively lowers NF levels 3-6 fold along optic axons without altering either rates of subunit synthesis or the rate of slow axonal transport of NF. Pulse labeling studies carried out over 90 days revealed a significantly faster rate of disappearance of NF from the stationary NF network of optic axons in NF-(H/M)(tailΔ) mice. Faster NF disappearance was accompanied by elevated levels of NF-L proteolytic fragments in NF-(H/M)(tailΔ) axons. We conclude that NF-H and NF-M C-terminal domains do not normally regulate NF transport rates as previously proposed, but instead increase the proteolytic resistance of NF, thereby stabilizing the stationary neurofilament cytoskeleton along axons.

Peripherin is a subunit of peripheral nerve neurofilaments: implications for differential vulnerability of CNS and peripheral nervous system axons

Peripherin, a neuronal intermediate filament protein implicated in neurodegenerative disease, coexists with the neurofilament triplet proteins [neurofilament light (NFL), medium (NFM), and heavy (NFH) chain] but has an unknown function. The earlier peak expression of peripherin than the triplet during brain development and its ability to form homopolymers, unlike the triplet, which are obligate heteropolymers, have supported a widely held view that peripherin and neurofilament triplets form separate filament systems. However, here, we demonstrate that, despite a postnatal decline in expression, peripherin is as abundant as the triplet in the adult PNS and exists in a relatively fixed stoichiometry with these subunits. Peripherin exhibits a distribution pattern identical to those of triplet proteins in sciatic axons and colocalizes with NFL on single neurofilaments by immunogold electron microscopy. Peripherin also coassembles into a single network of filaments containing NFL, NFM, and NFH with and without α-internexin in quadruple- or quintuple-transfected SW13vim(-) cells. Genetically deleting NFL in mice dramatically reduces peripherin content in sciatic axons. Moreover, peripherin mutations has been shown to disrupt the neurofilament network in transfected SW13vim(-) cells. These data show that peripherin and the neurofilament proteins are functionally interdependent. The results strongly support the view that, rather than forming an independent structure, peripherin is a subunit of neurofilaments in the adult PNS. Our findings provide a basis for its close relationship with neurofilaments in PNS diseases associated with neurofilament accumulation.

Production of gymnemic acid depends on medium, explants, PGRs, color lights, temperature, photoperiod, and sucrose sources in batch culture of Gymnema sylvestre

Gymnema sylvestre (R.Br.) is an important diabetic medicinal plant which yields pharmaceutically active compounds called gymnemic acid (GA). The present study describes callus induction and the subsequent batch culture optimization and GA quantification determined by linearity, precision, accuracy, and recovery. Best callus induction of GA was noticed in MS medium combined with 2,4-D (1.5 mg/L) and KN (0.5 mg/L). Evaluation and isolation of GA from the calluses derived from different plant parts, namely, leaf, stem and petioles have been done in the present case for the first time. Factors such as light, temperature, sucrose, and photoperiod were studied to observe their effect on GA production. Temperature conditions completely inhibited GA production. Out of the different sucrose concentrations tested, the highest yield (35.4 mg/g d.w) was found at 5% sucrose followed by 12 h photoperiod (26.86 mg/g d.w). Maximum GA production (58.28 mg/g d.w) was observed in blue light. The results showed that physical and chemical factors greatly influence the production of GA in callus cultures of G. sylvestre. The factors optimized for in vitro production of GA during the present study can successfully be employed for their large-scale production in bioreactors.

Calpastatin modulates APP processing in the brains of β-amyloid depositing but not wild-type mice

We report that neuronal overexpression of the endogenous inhibitor of calpains, calpastatin (CAST), in a mouse model of human Alzheimer's disease (AD) β-amyloidosis, the APP23 mouse, reduces β-amyloid (Aβ) pathology and Aβ levels when comparing aged, double transgenic (tg) APP23/CAST with APP23 mice. Concurrent with Aβ plaque deposition, aged APP23/CAST mice show a decrease in the steady-state brain levels of the amyloid precursor protein (APP) and APP C-terminal fragments (CTFs) when compared with APP23 mice. This CAST-dependent decrease in APP metabolite levels was not observed in single tg CAST mice expressing endogenous APP or in younger, Aβ plaque predepositing APP23/CAST mice. We also determined that the CAST-mediated inhibition of calpain activity in the brain is greater in the CAST mice with Aβ pathology than in non-APP tg mice, as demonstrated by a decrease in calpain-mediated cytoskeleton protein cleavage. Moreover, aged APP23/CAST mice have reduced extracellular signal-regulated kinase 1/2 (ERK1/2) activity and tau phosphorylation when compared with APP23 mice. In summary, in vivo calpain inhibition mediated by CAST transgene expression reduces Aβ pathology in APP23 mice, with our findings further suggesting that APP metabolism is modified by CAST overexpression as the mice develop Aβ pathology. Our results indicate that the calpain system in neurons is more responsive to CAST inhibition under conditions of Aβ pathology, suggesting that in the disease state neurons may be more sensitive to the therapeutic use of calpain inhibitors.

Genotoxicity in agricultural farmers from Guntur district of South India—A case study

Background: Pesticides play an important role in controlling the pests on agricultural crops and thereby to increase the yield of agricultural produce. Farmers occupationally exposed to pesticides during spraying activities are more prone to genotoxicity than unexposed. Aim: To assess the genotoxicity in farmers, engaged in spraying complex mixture of pesticides in the cultivation of cotton crops. Material and methods: A total number of 152 male subjects were selected randomly from Guntur district of Andhra Pradesh (AP), South India. The demographic particulars viz., personal habits, duration of exposure to pesticides, types of pesticides used were collected from the study subjects using an interview schedule. Among them 76 subjects were farmers and the remaining individuals served as unexposed or controls. Blood samples from these subjects were collected for assessing the genetic damage by chromosomal aberrations (CAs) test and micronucleus test (MNT). Results: The results of the study indicated that CA was significantly higher with 2.8% in farmers who were exposed to pesticides when compared to unexposed (0.72%). However, there was a minor difference in MN with 0.13% and 0.12% between exposed and unexposed which was not statistically significant ( p < 0.05). Conclusion: A correlation between CA frequency and exposure to benzene hexachloride (BHC) pesticide residue was observed.

In vitro callus and in vivo leaf extract of Gymnema sylvestre stimulate β-cells regeneration and anti-diabetic activity in Wistar rats

A methanol extract of Gymnema sylvestre leaf and callus showed anti-diabetic activities through regenerating β-cells. Optimum callus was developed under stress conditions of blue light with 2,4-D (1.5 mg/l) and KN (0.5 mg/l), which induced maximum biomass of green compact callus at 45 days, as determined by growth curve analysis. Leaf and optimum callus extracts contains gymnemic acid, which was analyzed using TLC, HPTLC and HPLC methods. The research reported here deals with leaf and callus extracts of G. sylvestre, which significantly increase the weight of the whole body, liver, pancreas and liver glycogen content in alloxan-induced diabetic rats (Wistar rats). The gymnemic acid of leaf and callus extracts significantly increases the regeneration of β-cells in treated rats, when compared with the standard diabetic rats. It could have potential as a pharmaceutical drug for insulin-dependent diabetes mellitus (IDDM).

Frequency of Mutations Induced by Radiations in Hexaploid Species of Triticum

The frequency of visible mutations induced by x-rays, phosphorus-32, and sulfur-35 was calculated in six hexaploid Triticum species. The species with spelted ears and winter habit showed a much lower mutation rate than the freethreshing, spring wheats.

Structural Changes in Reproductive Organs of Male Rats after Estradiol Benzoate Treatment

The effects of estradiol benzoate (E2B) at a dose of 50 micrograms/rat/day for 7, 15 and 24 days on histoarchitecture, histocytometry and relative weights of reproductive organs in mature albino rats were investigated. The results revealed that the organ weights, histology of the testis, epididymis, vas deferens and seminal vesicle of treated rats were considerably affected as a consequence of the treatment. The height of germinal/secretory epithelium and tubular diameter of these organs also declined, whereas the peritubular muscle layer thickness of epididymis and accessory gland was increased. In vas deferens, in contrast, the muscle layer was reduced. The induced effects of estrogen were related to the duration of the treatment and support our earlier data that estrogens have a direct effect on the testis.

In vitro genotoxicity assays to evaluate the role of vitamin A on arsenic in human lymphocytes

Ground water contamination of arsenic in drinking water is a burning problem worldwide; especially in West Bengal (India) and Bangladesh. The main endeavor in this study was to assess the role of vitamin A (2.72 microM/7 ml culture), a naturally occurring antioxidant upon arsenic-induced genotoxicity; with respect to chromosomal aberrations (structural and numerical) and micronuclei. Whole blood cultures set for 72 h were exposed to test chemicals for a period of 24 h ahead of harvesting. Arsenic concentrations tested in the present study are 0.36, 0.72 and 1.4 microM/7 ml culture. Mitomycin C (MMC), the direct acting mutagen was used as positive control. Our data indicates that at concentrations tested, arsenic-induced increase in the mean frequencies of these genotoxic indices were diminished by vitamin A, indicating its protective role towards cells from arsenic exerted injury.

In vitro cytogenetic effects of Andrographis paniculata (kalmegh) on arsenic

In vitro effects of arsenic in human peripheral lymphocytes (HPL) at three different doses - 3.6x10(-4), 1.4 x 10(-3) and 0.72 x 10(-3) microM for 24h before harvesting on sister chromatid exchanges (SCE), Cell cycle proliferative index/replicative index (CCPI/RI), %M(1), %M(2) and %M(3), population doubling time (PDT) and average generation time (AGT) were examined. Andrographis paniculata (commonly referred to as 'kalmegh') has been used for centuries in traditional Indian and Chinese herbal medicine as a safe, natural folk remedy for assorted health concerns. In the present study, kalmegh (0.01 microg/7ml culture media) was used along with the highest dose of arsenic; the results showed that arsenic induced increase in these genotoxic endpoints were fairly diminished by kalmegh. In addition, mutagenic in vitro effect of ethyl methanesulphonate (EMS) was used as a positive control in this study. It is thus concluded from this study that Andrographis has a protective role in arsenic toxicity.

Genotoxic effects in human lymphocytes exposed to arsenic and vitamin A

Arsenic is a ubiquitous trace element and a well-established human carcinogen. In search for an 'antidote' to this global poison, this work was undertaken to study the probable beneficial effect of vitamin A upon arsenic induced genotoxicity. Peripheral blood lymphocyte culture was carried out to study the effects of arsenic at three different dose levels (0.5, 1 and 2 microg) for 24 h prior to harvesting. In addition, mutagenic in vitro effect of ethyl methanesulphonate was studied as a positive control. Genotoxic variables presented here are sister chromatid exchanges (SCE), cell cycle proliferative index/replicative index (CCPI/RI), average generation time (AGT) and population doubling time (PDT). Inevitably, arsenic treatment showed dose-dependent augmentation in the incidences of SCE and CCPI/RI together with AGT and PDT. However, vitamin A supplemented arsenic cultures demonstrated remarkable resurgence in the described genotoxic parameters. This data shows that vitamin A might be a useful interventional treatment in arsenic poisoning.

Recent Advances in the Solid-Phase Combinatorial Synthetic Strategies for the Quinoxaline, Quinazoline and Benzimidazole Based Privileged Structures

Quinoxaline, quinazoline and benzimidazole based templates have been synthesized on solid-support employing different methodologies. This review enlightens academic and industrial examples of combinatorial synthesis for this type of heterocycles that appeared in the literature in the last decade. Hence, some of the important synthetic strategies for the generation of quinoxaline, quinazoline and benzimidazole based privileged structures, and the important biological activities for these heterocycles have been highlighted. Further, benzothiadiazinone, thioxoquinazolinone, cinnoline and indazole are also examined in this review.

Deleting the phosphorylated tail domain of the neurofilament heavy subunit does not alter neurofilament transport rate in vivo

Phosphorylation of the carboxyl tail domains of the neurofilament heavy (NF-H) and middle molecular weight (NF-M) subunits has been proposed to regulate the axonal transport of neurofilaments. To test this hypothesis, we recently constructed mice lacking the extensively phosphorylated NF-H tail domain (NF-HtailDelta) and showed that the transport rate of neurofilaments in optic axons is unaltered in the absence of this domain [M.V. Rao, M.L. Garcia, Y. Miyazaki, T. Gotow, A. Yuan, S. Mattina, C.M. Ward, N.A. Calcutt, Y. Uchiyama, R.A. Nixon, D.W. Cleveland, Gene replacement in mice reveals that the heavily phosphorylated tail of neurofilament heavy subunit does not affect axonal caliber or the transit of cargoes in slow axonal transport, J. Cell Biol. 158 (2002) 681-693]. However, Shea et al. proposed that deletion of NF-H carboxyl-terminal region accelerates the transport of a subpopulation of neurofilaments based on minor differences between tail-deleted and control mice in our axonal transport analysis. Here, we present additional evidence that neurofilament transport rate is unchanged after deleting the phosphorylated NF-H tail domain, establishing unequivocally that the NF-H tail domain alone does not regulate the rate of neurofilament transport in optic axons in vivo. Possible roles for tail domains as cross-bridges between a neurofilament and its neighbors or other cytoskeletal elements is discussed.

Biochemical studies of embryogenic and non-embryogenic callus of Cardiospermum halicacabum L

Some physiological and biochemical changes were measured between embryogenic and non-embryogenic callus obtained from Cardiospermum halicacabum. Combination of auxin with cytokinin was more favourable for high amount of callus formation. 2,4-D played a key role in triggering somatic embryo formation. Embryogenic callus had more total carbohydrate and starch contents, total free amino acids, nucleic acids, phenols and ascorbic acid. Non-embryogenic callus exhibited high chlorophyll content, total soluble sugar, protein, ammonia and enzymes like peroxidase and polyphenol oxidase. Thus, the present study indicated that the process of somatic embryogenesis was characterized by some biochemical and physiological changes induced by plant growth regulators.

Arsenic induced free radical toxicity in brain of mice

The present study was designed to investigate the in vivo effects of oral administration of arsenic trioxide (As2O3; 0.5 and 1 mg/kg body weight/day for 45 days) on cerebral hemispheres and cerebellum in male mice, Mus musculus. Arsenic reduced the concentration of glutathione (GSH) in cerebral hemisphere and cerebellum at both the dose levels; while increased lipid peroxidation (LPO) in cerebral hemisphere and cerebellum regions. Further, the activities of antioxidant enzymes viz., superoxide dismutase and catalase also declined in these two regions with dose indicating oxidative stress. This effect is caused by the action of reactive oxygen species (ROS) induced by arsenic exposure.

The neurofilament middle molecular mass subunit carboxyl-terminal tail domains is essential for the radial growth and cytoskeletal architecture of axons but not for regulating neurofilament transport rate

The phosphorylated carboxyl-terminal “tail” domains of the neurofilament (NF) subunits, NF heavy (NF-H) and NF medium (NF-M) subunits, have been proposed to regulate axon radial growth, neurofilament spacing, and neurofilament transport rate, but direct in vivo evidence is lacking. Because deletion of the tail domain of NF-H did not alter these axonal properties (Rao, M.V., M.L. Garcia, Y. Miyazaki, T. Gotow, A. Yuan, S. Mattina, C.M. Ward, N.S. Calcutt, Y. Uchiyama, R.A. Nixon, and D.W. Cleveland. 2002. J. Cell Biol. 158:681–693), we investigated possible functions of the NF-M tail domain by constructing NF-M tail–deleted (NF-M^tailΔ) mutant mice using an embryonic stem cell–mediated “gene knockin” approach that preserves normal ratios of the three neurofilament subunits. Mutant NF-M^tailΔ mice exhibited severely inhibited radial growth of both motor and sensory axons. Caliber reduction was accompanied by reduced spacing between neurofilaments and loss of long cross-bridges with no change in neurofilament protein content. These observations define distinctive functions of the NF-M tail in regulating axon caliber by modulating the organization of the neurofilament network within axons. Surprisingly, the average rate of axonal transport of neurofilaments was unaltered despite these substantial effects on axon morphology. These results demonstrate that NF-M tail–mediated interactions of neurofilaments, independent of NF transport rate, are critical determinants of the size and cytoskeletal architecture of axons, and are mediated, in part, by the highly phosphorylated tail domain of NF-M.

Neurofilament transport in vivo minimally requires hetero-oligomer formation

Neurofilament assembly requires at minimum the polymerization of neurofilament light chain (NF-L) with either neurofilament medium chain (NF-M) or neurofilament heavy chain (NF-H) subunits, but requirements for their axonal transport have long been controversial. Using a gene deletion approach, we generated mice containing only NF-L or NF-M. In vivo pulse radiolabeling analyses in retinal ganglion cell neurons revealed that NF-L alone is incapable of efficient transport, whereas nearly one-half of the normal level of NF-M is transported along optic axons in the absence of the other triplet subunits. Under these conditions, however, NF-M transport is completely abolished by deleting alpha-internexin. Our results strongly suggest that efficient neurofilament protein transport in vivo minimally requires hetero-oligomer formation. They also show that NF-M can partner with intermediate filament proteins other than the NF-H and NF-L subunits in neurons to support slow transport and possibly other functions of neuronal intermediate filaments.

Defective neurofilament transport in mouse models of amyotrophic lateral sclerosis: a review

Neurofilament proteins synthesized in the cell body of neurons are assembled and transported into axons, where they influence axon radial growth, axonal transport, and nerve conduction velocities. In diseased states, neurofilaments accumulate in cell bodies and proximal axons of affected neurons, and these lesions are characteristic of many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), spinal muscular atrophy (SMA), Charcot-Marie-Tooth disease type 2 (CMT2), and hereditary sensory motor neuropathy. Although the molecular mechanisms that contribute to these accumulations are not yet identified, transgenic mouse models are beginning to provide insight into the role of neurofilament transport in disease-related dysfunction of neurons. This review addresses axonal transport in mouse models of ALS and the special significance of neurofilament transport in this disease.

Myosin Va binding to neurofilaments is essential for correct myosin Va distribution and transport and neurofilament density

The identification of molecular motors that modulate the neuronal cytoskeleton has been elusive. Here, we show that a molecular motor protein, myosin Va, is present in high proportions in the cytoskeleton of mouse CNS and peripheral nerves. Immunoelectron microscopy, coimmunoprecipitation, and blot overlay analyses demonstrate that myosin Va in axons associates with neurofilaments, and that the NF-L subunit is its major ligand. A physiological association is indicated by observations that the level of myosin Va is reduced in axons of NF-L-null mice lacking neurofilaments and increased in mice overexpressing NF-L, but unchanged in NF-H-null mice. In vivo pulse-labeled myosin Va advances along axons at slow transport rates overlapping with those of neurofilament proteins and actin, both of which coimmunoprecipitate with myosin Va. Eliminating neurofilaments from mice selectively accelerates myosin Va translocation and redistributes myosin Va to the actin-rich subaxolemma and membranous organelles. Finally, peripheral axons of dilute-lethal mice, lacking functional myosin Va, display selectively increased neurofilament number and levels of neurofilament proteins without altering axon caliber. These results identify myosin Va as a neurofilament-associated protein, and show that this association is essential to establish the normal distribution, axonal transport, and content of myosin Va, and the proper numbers of neurofilaments in axons.

Gene replacement in mice reveals that the heavily phosphorylated tail of neurofilament heavy subunit does not affect axonal caliber or the transit of cargoes in slow axonal transport

The COOH-terminal tail of mammalian neurofilament heavy subunit (NF-H), the largest neurofilament subunit, contains 44-51 lysine-serine-proline repeats that are nearly stoichiometrically phosphorylated after assembly into neurofilaments in axons. Phosphorylation of these repeats has been implicated in promotion of radial growth of axons, control of nearest neighbor distances between neurofilaments or from neurofilaments to other structural components in axons, and as a determinant of slow axonal transport. These roles have now been tested through analysis of mice in which the NF-H gene was replaced by one deleted in the NF-H tail. Loss of the NF-H tail and all of its phosphorylation sites does not affect the number of neurofilaments, alter the ratios of the three neurofilament subunits, or affect the number of microtubules in axons. Additionally, it does not reduce interfilament spacing of most neurofilaments, the speed of action potential propagation, or mature cross-sectional areas of large motor or sensory axons, although its absence slows the speed of acquisition of normal diameters. Most surprisingly, at least in optic nerve axons, loss of the NF-H tail does not affect the rate of transport of neurofilament subunits.

Role of ascorbic acid on mercuric chloride-induced genotoxicity in human blood cultures

Efforts are made to find therapeutic agents capable of minimizing genotoxicity of various natural and man-made compounds. The genotoxicity induced by mercury compounds remains controversial. Therefore we have investigated the genotoxic effect of mercuric chloride (MC; HgCl(2)) at three concentrations (1.052, 5.262 and 10.524 microM) and role of L-ascorbic acid (vitamin C) at a concentration of 9.734 microM on MC-treated short-term human leucocyte cultures. We assessed the proliferative rate index (PRI), sister chromatid exchange (SCE) and chromosomal aberrations (CAS) in control and MC-treated cultures with and without vitamin C supplementation. The results showed that MC has no effect on cell-cycle kinetics, but the frequency of SCE/cell was significantly higher in a dose-dependent manner than control values. HgCl(2) also significantly induced C-anaphases (abnormal mitosis) in blood cultures. These effects were prevented by the addition of vitamin C to MC-treated cultures. The data indicate the mutagenic activity of MC and the protective role of vitamin C on mercury-induced genotoxicity in human blood cultures is probably due to its strong antioxidant and nucleophilic nature.

Protective effect of vitamin E against mercuric chloride reproductive toxicity in male mice

Mercury intoxication has been associated with male reproductive toxicity in experimental animals and mercury may have the potential to produce adverse effects on fertility in men. Vitamin E may protect against toxic effects of mercury in the liver and other tissues. To investigate the protective role of vitamin E against mercuric chloride toxicity for the testis, epididymis, and vas deferens of adult male mice, animals were treated with either mercuric chloride 1.25 mg/kg/day, vitamin E 2 mg/kg/kg, or a combination of the two treatments. Control animals were treated with water. Treatments were administered by daily gavage for 45 days. An additional group of animals treated with mercuric chloride were permitted to recover for 45 days after mercuric chloride treatments. Parameters studied included serum testosterone, epididymal sperm count, motility, and morphology, epididymal and vas deferens adenosine triphosphatase (ATPase), phosphorylase, sialic acid, glycogen and protein, testicular succinate dehydrogenase (SDH), phosphatases, cholesterol, ascorbic acid, and glutathione. Fertility was evaluated by sperm positive vaginal smears after overnight cohabitation with a female. Mercuric chloride produced a reduction in epididymal sperm count, sperm motility, and sperm viability, and there were no sperm-positive smears in this group. Biochemical tests from the male reproductive organs were also altered by mercuric chloride treatment. Coadministration of vitamin E with mercuric chloride prevented the changes in sperm and biochemical parameters and was associated with control rates of sperm positive smears after cohabitation. Animals given vitamin E with mercuric chloride also had lower concentrations of mercury in the testis, epididimyis, and vas deferens. Permitting animals to recover for 45 days after mercuric chloride treatment resulted in partial recovery of sperm and biochemical parameters. Vitamin E cotreatment has a protective role against mercury-induced male reproductive toxicity.