Particulate mechanics of granular soils

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Ca2+ sensor proteins in dendritic spines: a race for Ca2+

Dendritic spines are believed to be micro-compartments of Ca2+ regulation. In a recent study, it was suggested that the ubiquitous and evolutionarily conserved Ca2+ sensor, calmodulin (CaM), is the first to intercept Ca2+ entering the spine and might be responsible for the fast decay of Ca2+ transients in spines. Neuronal calcium sensor (NCS) and neuronal calcium-binding protein (nCaBP) families consist of Ca2+ sensors with largely unknown synaptic functions despite an increasing number of interaction partners. Particularly how these sensors operate in spines in the presence of CaM has not been discussed in detail before. The limited Ca2+ resources and the existence of common targets create a highly competitive environment where Ca2+ sensors compete with each other for Ca2+ and target binding. In this review, we take a simple numerical approach to put forth possible scenarios and their impact on signaling via Ca2+ sensors of the NCS and nCaBP families. We also discuss the ways in which spine geometry and properties of ion channels, their kinetics and distribution, alter the spatio-temporal aspects of Ca2+ transients in dendritic spines, whose interplay with Ca2+ sensors in turn influences the race for Ca2+

A study of thyroid disorders in females attending obstetrics and gynecology outpatient department of a tertiary care institute of central India

Background: The study was conducted with an objective to study the spectrum of thyroid dysfunction and to correlate clinical symptoms with abnormal thyroid function.Methods: A total no. of 1010 women, attending the Gynecology and Medicine OPD of M.Y. Hospital, Indore, MP were subjected to screening with TSH levels estimation. The women with abnormal TSH values were then evaluated for various clinical symptoms.Results: Out of total 1010 women, 120 had abnormal TSH. The prevalence was high (11.88%). Hypothyroidism (71.66%) was more common than hyperthyroidism (28.33%). The incidence of thyroid disorders was higher with advancing age. Abnormal TSH levels had a linear correlation with increasing BMI. Majority of the patients presented with vague symptoms commonest being weight changes (24.15%). Abnormal uterine bleeding (5.8%) and infertility (5.8%) were the chief gynecological complaints. Hypertension was strongly associated with thyroid dysfunction.Conclusions: Thyroid dysfunction is a highly prevalent problem in female population. Estimation of TSH level is a good screening tool; however complete thyroid profile is required before initiating treatment. The incidence increases with advancing age, hypothyroidism being the more common variant. Classical symptoms may not be present in majority of patients who have a vague clinical picture. This study recommends universal screening of women for thyroid dysfunction in view of high prevalence, vague and varied presentation.  

A study of role of colour Doppler in evaluation of abnormal uterine bleeding at medicine and gynecology departments at a tertiary care institute of central India

Background: Abnormal uterine bleeding (AUB) at any age in women’s life is disruptive and worrisome. The purpose of the study is to determine the effectiveness of color Doppler transvaginal ultrasonography (CDTU) in detection of intrauterine pathology in those patients with abnormal uterine bleeding.Methods: The present study was conducted on 50 patients of AUB selected from Gynecology and Medicine OPD of M.G.M. Medical College and M.Y. and associated group of hospitals, Indore during the period of May 2012 to December 2012. All patients underwent D&C (for endometrial biopsy) to evaluate ultrasonographic findings. Ultrasonographic variables considered were: endometrial thickness, gray-scale and color Doppler sonographic findings, resistance index and pulsatility index.Results: CDTU showed abnormal studies in 11 patients (22%) cases. Endometrial biopsy revealed abnormalities in 14 women. 91% of cases, which were having abnormal CDTU, had abnormal endometrium. 10% cases were missed by CDTU and were having abnormal HPR of which 67% had simple endometrial hyperplasia; rest 33%-cystic glandular hyperplasia. In abnormal CDTU finding group, only 9% cases had normal HPR. Color doppler effectively diagnosed all the malignant and potentially malignant states.Conclusions: CDTU can be used to as an effective tool in woman with evaluation of AUB after TVS has been performed for visualizing endometrium

A high-molecular-weight outer membrane protein of Xanthomonas oryzae pv. oryzae exhibits similarity to non-fimbrial adhesins of animal pathogenic bacteria and is required for optimum virulence

Transposon insertions in a novel 3.798 kb open reading frame (ORF) of the rice pathogen, Xanthomonas oryzae pv. oryzae (Xoo) cause virulence deficiency and altered colony/lawn morphology. This ORF encodes a protein, XadA, of 1265 amino acids that exhibits significant similarity to non-fimbrial adhesins of animal pathogenic bacteria such as Yersinia YadA and Moraxella UspA1. An interesting feature is that the YadA similarity region is repeated six times within the XadA sequence and encompasses almost the entire length of the protein. Anti-XadA antibodies identified a 110 kDa outer membrane protein that was sensitive to protease treatment of whole cells. XadA expression is induced in minimal medium. Homology modelling suggests that XadA adopts a β-helix conformation-like pertactin, a non-fimbrial adhesin of Bordetella pertussis. This work is the first characterization of a non-fimbrial adhesin-like molecule in a plant pathogenic bacterium. It extends our knowledge about the repertoire of homologous virulence factors that are deployed by animal and plant pathogenic bacteria to include functions potentially involved in adhesion

N-Terminal myristoylation alters the calcium binding pathways in neuronal calcium sensor-1

Neuronal calcium sensor-1 (NCS-1) interacts with many membranes and cytosolic proteins, both in a Ca2+-dependent and in a Ca2+-independent manner, and its physiological role is governed by its N-terminal myristoylation. To understand the role of myristoylation in altering Ca2+ response and other basic biophysical properties, we have characterized the Ca2+ filling pathways in both myristoylated (myr) and non-myristoylated (non-myr) forms of NCS-1. We have observed that Ca2+ binds simultaneously to all three active EF-hands in non-myr NCS-1, whereas in the case of myr NCS-1, the process is sequential, where the second EF-hand is filled first, followed by the third and fourth EF-hands. In the case of myr NCS-1, the observed sequential Ca2+ binding process becomes more prominent in the presence of Mg2+. Besides, the analysis of 15N-relaxation data reveals that non-myr NCS-1 is more dynamic than myr NCS-1. The overall molecular tumbling correlation time increases by approximately 20% upon myristoylation. Comparing the apo forms of non-myr NCS-1 and myr NCS-1, we found the possibility of existence of some substates, which are structurally closer to the holo form of the protein. There are more such substates in the case of non-myr NCS-1 than in the case of the myr NCS-1, suggesting that the former accesses larger volumes of conformational substates compared with the latter. Further, the study reveals that the possibility of Ca2+ binding simultaneously to different parts of the protein is more favourable in non-myr NCS-1 than in myr NCS-1

TRUST BASED SECURE AODV IN MANET

Abstract- The nature of self-organization and the limitation of individual resources, MANET always confront security and selfishness issues. In this thesis, we design trusted routing protocols using trusted frame works and intrusion detection system (secure protocol) f or MANET. Trust combination algorithms and trust mapping functions are provided in this model, where the former can aggregate different opinions together to get a new recommendation opinion. Based on this trust model, we design our trusted routing protocols for MANET called TAODV on top of Ad Hoc On-demand Distance Vector (AODV) routing protocol. We extend the routing table and the routing messages of ADOV with trust information which can be updated directly through monitoring in the neighborhood. When performing trusted routing discovery, unlike those cryptographic schemes that perform signature generation or verification at every routing packet, we just combine the recommen ded opinions together and make a routing judgment based on each element of the new opinion. In this way the computation overhead can be largely reduced, and the trustworthiness of the routing procedure can be guaranteed as well. In this thesis, we implement the security and sel fishness issues of wireless networks, either in non-cooperative form or in cooperative form. Our results show that the cumulative utilities of cooperative nodes are increased steadily and the selfish nodes cannot get more utilities by behaving selfishly than cooperatively