Proceedings of the 16th international conference on Hybrid systems: computation and control - HSCC '13, 2013
Collective food transport in ant colonies is a striking, albeit poorly understood, example of coo... more Collective food transport in ant colonies is a striking, albeit poorly understood, example of coordinated group behavior in nature that can serve as a template for robust, decentralized multi-robot cooperative manipulation strategies. We investigate this behavior in Aphaenogaster cockerelli ants in order to derive a model of the ants' roles and behavioral transitions and the resulting dynamics of a transported load. In experimental trials, A. cockerelli are induced to transport a rigid artificial load to their nest. From video recordings of the trials, we obtain time series data on the load position and the population counts of ants in three roles. From our observations, we develop a stochastic hybrid system model that describes the time evolution of these variables and that can be used to derive the dynamics of their statistical moments. In our model, ants switch stochastically between roles at constant, unknown probability rates, and ants in one role pull on the load with a force that acts as a proportional controller on the load velocity with unknown gain and set point. We compute these unknown parameters by using standard numerical optimization techniques to fit the time evolution of the means of the load position and population counts to the averaged experimental time series. The close fit of our model to the averaged data and to data for individual trials demonstrates the accuracy of our proposed model in predicting the ant behavior.
Reflexes initiated by the carotid body, the principal O2-sensing organ, are critical for maintain... more Reflexes initiated by the carotid body, the principal O2-sensing organ, are critical for maintaining cardiorespiratory homeostasis during hypoxia. O2 sensing by the carotid body requires carbon monoxide (CO) generation by heme oxygenase-2 (HO-2) and hydrogen sulfide (H2S) synthesis by cystathionine-γ-lyase (CSE). We report that O2 stimulated the generation of CO, but not that of H2S, and required two cysteine residues in the heme regulatory motif (Cys(265) and Cys(282)) of HO-2. CO stimulated protein kinase G (PKG)-dependent phosphorylation of Ser(377) of CSE, inhibiting the production of H2S. Hypoxia decreased the inhibition of CSE by reducing CO generation resulting in increased H2S, which stimulated carotid body neural activity. In carotid bodies from mice lacking HO-2, compensatory increased abundance of nNOS (neuronal nitric oxide synthase) mediated O2 sensing through PKG-dependent regulation of H2S by nitric oxide. These results provide a mechanism for how three gases work in ...
Advances in experimental medicine and biology, 2009
Physiological responses to hypoxia either continuous (CH) or intermittent (IH) depend on the O(2)... more Physiological responses to hypoxia either continuous (CH) or intermittent (IH) depend on the O(2)-sensing ability of the peripheral arterial chemoreceptors, especially the carotid bodies, and the ensuing reflexes play important roles in maintaining homeostasis. The purpose of this article is to summarize the effects of CH and IH on carotid body function and the underlying mechanisms. CH increases baseline carotid body activity and sensitizes the response to acute hypoxia. These effects are associated with hyperplasia of glomus cells and neovascularization. Enhanced hypoxic sensitivity is due to alterations in ion current densities as well as changes in neurotransmitter dynamics and recruitment of additional neuromodulators (endothelin-1, ET-1) in glomus cells. Morphological alterations are in part due to up-regulation of growth factors (e.g. VEGF). Hypoxia-inducible factor-1 (HIF-1), a transcriptional activator might underlie the remodeling of carotid body structure and function by ...
FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 1988
The apo 1.3S subunit of transcarboxylase contains the sequence Ala-87-Met-88-Lys-89-Met-90, and i... more The apo 1.3S subunit of transcarboxylase contains the sequence Ala-87-Met-88-Lys-89-Met-90, and it is Lys-89 that is biotinated. This sequence is highly conserved in all the biotin enzymes that have been sequenced (with the exception of acetyl-CoA carboxylase from chicken liver, which has Val in place of Ala). The role of Met-88 and Met-90 in specifying Lys-89 for biotination by synthetase was examined by site-directed mutagenesis. Genes of the 1.3S subunit coding for Thr-88, Leu-88, or Leu-90 were generated by oligonucleotide-directed in vitro mutagenesis and expressed in Escherichia coli. The mutated apo 1.3S subunits were isolated and the biotination by homogeneous synthetase from Propionibacterium shermanii was compared with that of the apo wild-type subunit. The Vmax for the apo mutants was the same as that for the apo wild type, but when Leu was substituted for Met-88 or Met-90, the Km for the mutant was lower than that of the wild-type or mutant Thr-88. The activity of the sy...
This work presents a novel control approach for allocating a robotic swarm among boundaries. It r... more This work presents a novel control approach for allocating a robotic swarm among boundaries. It represents the first step toward developing a methodology for encounter-based swarm allocation that incorporates rigorously characterized spatial effects in the system without requiring analytical expressions for encounter rates. Our approach utilizes a macroscopic model of the swarm population dynamics to design stochastic robot control policies that result in target allocations of robots to the boundaries of regions of different types. The control policies use only local information and have provable guarantees on the collective swarm behavior. We analytically derive the relationship between the stochastic control policies and target allocations for a scenario in which circular robots avoid collisions with each other, bind to boundaries of disk-shaped regions, and command bound robots to unbind. We validate this relationship in simulation and show that it is robust to environmental changes, such as a change in the number or size of robots and disks.
Journal of Dynamic Systems, Measurement, and Control, 2014
ABSTRACT This paper introduces a novel stochastic framework for allocating a swarm of robots amon... more ABSTRACT This paper introduces a novel stochastic framework for allocating a swarm of robots among boundaries of circular regions. This approach requires no communication between robots, and yet stable team sizes are maintained around these regions. The control policy on each robot is implemented as a small set of event-triggered probabilistic rules for binding and unbinding to those regions. A macroscopic model of the robot swarm is used to design these probabilities to achieve a desired average allocation for each type of region. Our approach is similar to other stochastic multi-robot strategies in the literature; however, those approaches also incorporate internally generated timer events which have to be carefully tuned to match encounter rates generated by the external environment. In contrast, we avoid internally generated events, and so our approach produces stable equilibria that are invariant to changes in the environment. Additionally, for sufficiently large robot teams, the robot-controller design for each region type is independent of the design for any other region type. In this paper, we validate these theoretical results in simulation. Although this paper focuses on the application of allocating robots to boundaries, it more generally presents a new paradigm for robust stochastic programming based on using only externally generated events.
Respiratory physiology & neurobiology, Jan 10, 2008
Recurrent apneas are characterized by transient repetitive cessations of breathing (two breaths d... more Recurrent apneas are characterized by transient repetitive cessations of breathing (two breaths duration or longer) resulting in periodic decreases in arterial blood PO2 or chronic intermittent hypoxia (IH). Patients with recurrent apneas and experimental animals exposed to chronic IH exhibit cardio-respiratory morbidities. The purpose of this article is to highlight the current information on the transcriptional mechanisms associated with chronic IH. Studies on rodents and cell cultures have shown that IH activates a variety of transcription factors including the hypoxia-inducible factor-1 (HIF-1), c-fos (immediate early gene), nuclear factor of activated T-cells (NFAT), and nuclear factor kB (NF-kB). The signaling pathways associated with transcriptional activation associated with IH differ from continuous hypoxia (CH). Compared to same duration and intensity of CH, IH is more potent in activating HIF-1 and c-fos and also results in long-lasting accumulation of HIF-1alpha and c-fo...
Indian journal of occupational and environmental medicine, 2011
Environmental sanitation is a major public health issue in India. Recent interventional studies o... more Environmental sanitation is a major public health issue in India. Recent interventional studies on environmental sanitation in India highlighted the importance of prioritizing control strategies. Research related to the appropriate cost-effective intervention strategies and their implementation in Indian context is a big challenge. This paper discusses various intervention strategies related to environmental sanitation in India and emphasizes to prioritize it according to the need of country.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 2013
In the present investigation, functionalization of gold nanoparticles synthesized using propanoic... more In the present investigation, functionalization of gold nanoparticles synthesized using propanoic acid 2-(3-acetoxy-4,4,14-trimethylandrost-8-en-17-yl) (PAT) an active biocomponent isolated from Cassia auriculata is studied in detail. On reaction of PAT with aqueous HAuCl4, rapid formation of stable gold nanoparticles was achieved. Formation of gold nanoparticles was confirmed by UV-vis spectroscopy, XRD, GC-MS,FTIR, TEM and SEM with EDAX. Gold nanoparticles mostly were monodisperse, spherical in shape and ranged in size 12-41 nm. Gold nanoparticles synthesised using PAT was administered to alloxan (150 mg/kg body weight) induced diabetic male albino rats at different doses (0.25, 0.5, 0.75 and 1.0mg/kg body weight) for 28 days. Plasma glucose level, cholesterol and triglyceride were significantly (p<0.001) reduced in experimental animals treated with gold nanoparticles at dosage of 0.5mg/kg body weight and plasma insulin increased significantly. The newly genre green gold nanopa...
American journal of physiology. Cell physiology, Jan 15, 2015
Arterial blood O2 levels are detected by specialized sensory organs called carotid bodies. Voltag... more Arterial blood O2 levels are detected by specialized sensory organs called carotid bodies. Voltage-gated Ca(2+) channels (VGCCs) are important for carotid body O2 sensing. Given that T-type VGCCs contribute to nociceptive sensation, we hypothesized that they participate in carotid body O2 sensing. The rat carotid body expresses high levels of mRNA encoding the α1H-subunit, and α1H protein is localized to glomus cells, the primary O2-sensing cells in the chemoreceptor tissue, suggesting that CaV3.2 is the major T-type VGCC isoform expressed in the carotid body. Mibefradil and TTA-A2, selective blockers of the T-type VGCC, markedly attenuated elevation of hypoxia-evoked intracellular Ca(2+) concentration, secretion of catecholamines from glomus cells, and sensory excitation of the rat carotid body. Similar results were obtained in the carotid body and glomus cells from CaV3.2 knockout (Cacna1h(-/-)) mice. Since cystathionine-γ-lyase (CSE)-derived H2S is a critical mediator of the caro...
Previous studies reported that chronic intermittent hypoxia (CIH) results in an imbalanced expres... more Previous studies reported that chronic intermittent hypoxia (CIH) results in an imbalanced expression of hypoxia-inducible factor-α (HIF-α) isoforms and oxidative stress in rodents, which may be due either to the direct effect of CIH or indirectly via hitherto uncharacterized mechanism(s). As neural activity is a potent regulator of gene transcription, we hypothesized that carotid body (CB) neural activity contributes to CIH-induced HIF-α isoform expression and oxidative stress in the chemoreflex pathway. Experiments were performed on adult rats exposed to CIH for 10 days. Rats exposed to CIH exhibited: increased HIF-1α and decreased HIF-2α expression; increased NADPH oxidase 2 and decreased superoxide dismutase 2 expression; and oxidative stress in the nucleus tractus solitarius and rostral ventrolateral medulla as well as in the adrenal medulla (AM), a major end organ of the sympathetic nervous system. Selective ablation of the CB abolished these effects. In the AM, sympathetic ac...
Histoplasmosis, a granulomatous mycosis caused by the fungus Histoplasma capsulatum, is known to ... more Histoplasmosis, a granulomatous mycosis caused by the fungus Histoplasma capsulatum, is known to primarily affect the lungs and the immune system, with involvement of skeletal system as a rare manifestation, in which case the disease usually assumes multifocality. We present a singular case of a young man diagnosed to have an isolated skeletal histoplasmosis involving the body of sternum where F-FDG PET/CT played major role in both diagnosis and in response evaluation to antifungal therapy.
ABSTRACT Abstract Novel synthesis of water-soluble biogenic CdS nanotriangles at room temperature... more ABSTRACT Abstract Novel synthesis of water-soluble biogenic CdS nanotriangles at room temperature using fenugreek (Trigonella foenum graecum) aqueous seed extract via a facile, green and environmentally benign route is being reported. The X-ray diffraction (XRD) analysis confirmed that CdS nanotriangles were of the wurtzite structure. Fourier Transform Infrared (FT-IR) spectrum showed the role of fenugreek seed extract in the formation of CdS nanotriangles. The optical absorption studies reveal that CdS nanotriangles exhibit strong quantum confinement effect as the optical energy band gap increased significantly compared to the bulk CdS. The transmission electron microscopy (TEM) image showed that the CdS nanotriangles are uniform in size and shape in the range of 53 nm.
Development of novel antidiabetic agents using various organic compounds and biomolecules has bee... more Development of novel antidiabetic agents using various organic compounds and biomolecules has been in practice for a long time. Recently, nanomaterials are also being used in antidiabetic studies for their unique properties such as small size, biocompatibility and ability to penetrate cell membrane for carrying drugs. Herein, in vivo antidiabetic activity of gold nanoparticles (AuNPs) synthesized using the antidiabetic potent plant Gymnema sylvestre R. Br on wistar albino rats has been evaluated. The formation of AuNPs and their morphology were confirmed using spectroscopic and microscopic analyses, respectively. The treatment of AuNPs has shown significant reduction in blood glucose level on diabetic rats. AuNPs were also tested for its anti-inflammatory effect by estimating the serum levels of tumor necrosis factor-alpha (TNF-␣), interleukin-6 (IL-6) and high-sensitive C-reactive protein (CRP).
Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of ... more Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet-visible (UV-vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of~5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus.
Proceedings of the 16th international conference on Hybrid systems: computation and control - HSCC '13, 2013
Collective food transport in ant colonies is a striking, albeit poorly understood, example of coo... more Collective food transport in ant colonies is a striking, albeit poorly understood, example of coordinated group behavior in nature that can serve as a template for robust, decentralized multi-robot cooperative manipulation strategies. We investigate this behavior in Aphaenogaster cockerelli ants in order to derive a model of the ants' roles and behavioral transitions and the resulting dynamics of a transported load. In experimental trials, A. cockerelli are induced to transport a rigid artificial load to their nest. From video recordings of the trials, we obtain time series data on the load position and the population counts of ants in three roles. From our observations, we develop a stochastic hybrid system model that describes the time evolution of these variables and that can be used to derive the dynamics of their statistical moments. In our model, ants switch stochastically between roles at constant, unknown probability rates, and ants in one role pull on the load with a force that acts as a proportional controller on the load velocity with unknown gain and set point. We compute these unknown parameters by using standard numerical optimization techniques to fit the time evolution of the means of the load position and population counts to the averaged experimental time series. The close fit of our model to the averaged data and to data for individual trials demonstrates the accuracy of our proposed model in predicting the ant behavior.
Reflexes initiated by the carotid body, the principal O2-sensing organ, are critical for maintain... more Reflexes initiated by the carotid body, the principal O2-sensing organ, are critical for maintaining cardiorespiratory homeostasis during hypoxia. O2 sensing by the carotid body requires carbon monoxide (CO) generation by heme oxygenase-2 (HO-2) and hydrogen sulfide (H2S) synthesis by cystathionine-γ-lyase (CSE). We report that O2 stimulated the generation of CO, but not that of H2S, and required two cysteine residues in the heme regulatory motif (Cys(265) and Cys(282)) of HO-2. CO stimulated protein kinase G (PKG)-dependent phosphorylation of Ser(377) of CSE, inhibiting the production of H2S. Hypoxia decreased the inhibition of CSE by reducing CO generation resulting in increased H2S, which stimulated carotid body neural activity. In carotid bodies from mice lacking HO-2, compensatory increased abundance of nNOS (neuronal nitric oxide synthase) mediated O2 sensing through PKG-dependent regulation of H2S by nitric oxide. These results provide a mechanism for how three gases work in ...
Advances in experimental medicine and biology, 2009
Physiological responses to hypoxia either continuous (CH) or intermittent (IH) depend on the O(2)... more Physiological responses to hypoxia either continuous (CH) or intermittent (IH) depend on the O(2)-sensing ability of the peripheral arterial chemoreceptors, especially the carotid bodies, and the ensuing reflexes play important roles in maintaining homeostasis. The purpose of this article is to summarize the effects of CH and IH on carotid body function and the underlying mechanisms. CH increases baseline carotid body activity and sensitizes the response to acute hypoxia. These effects are associated with hyperplasia of glomus cells and neovascularization. Enhanced hypoxic sensitivity is due to alterations in ion current densities as well as changes in neurotransmitter dynamics and recruitment of additional neuromodulators (endothelin-1, ET-1) in glomus cells. Morphological alterations are in part due to up-regulation of growth factors (e.g. VEGF). Hypoxia-inducible factor-1 (HIF-1), a transcriptional activator might underlie the remodeling of carotid body structure and function by ...
FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 1988
The apo 1.3S subunit of transcarboxylase contains the sequence Ala-87-Met-88-Lys-89-Met-90, and i... more The apo 1.3S subunit of transcarboxylase contains the sequence Ala-87-Met-88-Lys-89-Met-90, and it is Lys-89 that is biotinated. This sequence is highly conserved in all the biotin enzymes that have been sequenced (with the exception of acetyl-CoA carboxylase from chicken liver, which has Val in place of Ala). The role of Met-88 and Met-90 in specifying Lys-89 for biotination by synthetase was examined by site-directed mutagenesis. Genes of the 1.3S subunit coding for Thr-88, Leu-88, or Leu-90 were generated by oligonucleotide-directed in vitro mutagenesis and expressed in Escherichia coli. The mutated apo 1.3S subunits were isolated and the biotination by homogeneous synthetase from Propionibacterium shermanii was compared with that of the apo wild-type subunit. The Vmax for the apo mutants was the same as that for the apo wild type, but when Leu was substituted for Met-88 or Met-90, the Km for the mutant was lower than that of the wild-type or mutant Thr-88. The activity of the sy...
This work presents a novel control approach for allocating a robotic swarm among boundaries. It r... more This work presents a novel control approach for allocating a robotic swarm among boundaries. It represents the first step toward developing a methodology for encounter-based swarm allocation that incorporates rigorously characterized spatial effects in the system without requiring analytical expressions for encounter rates. Our approach utilizes a macroscopic model of the swarm population dynamics to design stochastic robot control policies that result in target allocations of robots to the boundaries of regions of different types. The control policies use only local information and have provable guarantees on the collective swarm behavior. We analytically derive the relationship between the stochastic control policies and target allocations for a scenario in which circular robots avoid collisions with each other, bind to boundaries of disk-shaped regions, and command bound robots to unbind. We validate this relationship in simulation and show that it is robust to environmental changes, such as a change in the number or size of robots and disks.
Journal of Dynamic Systems, Measurement, and Control, 2014
ABSTRACT This paper introduces a novel stochastic framework for allocating a swarm of robots amon... more ABSTRACT This paper introduces a novel stochastic framework for allocating a swarm of robots among boundaries of circular regions. This approach requires no communication between robots, and yet stable team sizes are maintained around these regions. The control policy on each robot is implemented as a small set of event-triggered probabilistic rules for binding and unbinding to those regions. A macroscopic model of the robot swarm is used to design these probabilities to achieve a desired average allocation for each type of region. Our approach is similar to other stochastic multi-robot strategies in the literature; however, those approaches also incorporate internally generated timer events which have to be carefully tuned to match encounter rates generated by the external environment. In contrast, we avoid internally generated events, and so our approach produces stable equilibria that are invariant to changes in the environment. Additionally, for sufficiently large robot teams, the robot-controller design for each region type is independent of the design for any other region type. In this paper, we validate these theoretical results in simulation. Although this paper focuses on the application of allocating robots to boundaries, it more generally presents a new paradigm for robust stochastic programming based on using only externally generated events.
Respiratory physiology & neurobiology, Jan 10, 2008
Recurrent apneas are characterized by transient repetitive cessations of breathing (two breaths d... more Recurrent apneas are characterized by transient repetitive cessations of breathing (two breaths duration or longer) resulting in periodic decreases in arterial blood PO2 or chronic intermittent hypoxia (IH). Patients with recurrent apneas and experimental animals exposed to chronic IH exhibit cardio-respiratory morbidities. The purpose of this article is to highlight the current information on the transcriptional mechanisms associated with chronic IH. Studies on rodents and cell cultures have shown that IH activates a variety of transcription factors including the hypoxia-inducible factor-1 (HIF-1), c-fos (immediate early gene), nuclear factor of activated T-cells (NFAT), and nuclear factor kB (NF-kB). The signaling pathways associated with transcriptional activation associated with IH differ from continuous hypoxia (CH). Compared to same duration and intensity of CH, IH is more potent in activating HIF-1 and c-fos and also results in long-lasting accumulation of HIF-1alpha and c-fo...
Indian journal of occupational and environmental medicine, 2011
Environmental sanitation is a major public health issue in India. Recent interventional studies o... more Environmental sanitation is a major public health issue in India. Recent interventional studies on environmental sanitation in India highlighted the importance of prioritizing control strategies. Research related to the appropriate cost-effective intervention strategies and their implementation in Indian context is a big challenge. This paper discusses various intervention strategies related to environmental sanitation in India and emphasizes to prioritize it according to the need of country.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 2013
In the present investigation, functionalization of gold nanoparticles synthesized using propanoic... more In the present investigation, functionalization of gold nanoparticles synthesized using propanoic acid 2-(3-acetoxy-4,4,14-trimethylandrost-8-en-17-yl) (PAT) an active biocomponent isolated from Cassia auriculata is studied in detail. On reaction of PAT with aqueous HAuCl4, rapid formation of stable gold nanoparticles was achieved. Formation of gold nanoparticles was confirmed by UV-vis spectroscopy, XRD, GC-MS,FTIR, TEM and SEM with EDAX. Gold nanoparticles mostly were monodisperse, spherical in shape and ranged in size 12-41 nm. Gold nanoparticles synthesised using PAT was administered to alloxan (150 mg/kg body weight) induced diabetic male albino rats at different doses (0.25, 0.5, 0.75 and 1.0mg/kg body weight) for 28 days. Plasma glucose level, cholesterol and triglyceride were significantly (p<0.001) reduced in experimental animals treated with gold nanoparticles at dosage of 0.5mg/kg body weight and plasma insulin increased significantly. The newly genre green gold nanopa...
American journal of physiology. Cell physiology, Jan 15, 2015
Arterial blood O2 levels are detected by specialized sensory organs called carotid bodies. Voltag... more Arterial blood O2 levels are detected by specialized sensory organs called carotid bodies. Voltage-gated Ca(2+) channels (VGCCs) are important for carotid body O2 sensing. Given that T-type VGCCs contribute to nociceptive sensation, we hypothesized that they participate in carotid body O2 sensing. The rat carotid body expresses high levels of mRNA encoding the α1H-subunit, and α1H protein is localized to glomus cells, the primary O2-sensing cells in the chemoreceptor tissue, suggesting that CaV3.2 is the major T-type VGCC isoform expressed in the carotid body. Mibefradil and TTA-A2, selective blockers of the T-type VGCC, markedly attenuated elevation of hypoxia-evoked intracellular Ca(2+) concentration, secretion of catecholamines from glomus cells, and sensory excitation of the rat carotid body. Similar results were obtained in the carotid body and glomus cells from CaV3.2 knockout (Cacna1h(-/-)) mice. Since cystathionine-γ-lyase (CSE)-derived H2S is a critical mediator of the caro...
Previous studies reported that chronic intermittent hypoxia (CIH) results in an imbalanced expres... more Previous studies reported that chronic intermittent hypoxia (CIH) results in an imbalanced expression of hypoxia-inducible factor-α (HIF-α) isoforms and oxidative stress in rodents, which may be due either to the direct effect of CIH or indirectly via hitherto uncharacterized mechanism(s). As neural activity is a potent regulator of gene transcription, we hypothesized that carotid body (CB) neural activity contributes to CIH-induced HIF-α isoform expression and oxidative stress in the chemoreflex pathway. Experiments were performed on adult rats exposed to CIH for 10 days. Rats exposed to CIH exhibited: increased HIF-1α and decreased HIF-2α expression; increased NADPH oxidase 2 and decreased superoxide dismutase 2 expression; and oxidative stress in the nucleus tractus solitarius and rostral ventrolateral medulla as well as in the adrenal medulla (AM), a major end organ of the sympathetic nervous system. Selective ablation of the CB abolished these effects. In the AM, sympathetic ac...
Histoplasmosis, a granulomatous mycosis caused by the fungus Histoplasma capsulatum, is known to ... more Histoplasmosis, a granulomatous mycosis caused by the fungus Histoplasma capsulatum, is known to primarily affect the lungs and the immune system, with involvement of skeletal system as a rare manifestation, in which case the disease usually assumes multifocality. We present a singular case of a young man diagnosed to have an isolated skeletal histoplasmosis involving the body of sternum where F-FDG PET/CT played major role in both diagnosis and in response evaluation to antifungal therapy.
ABSTRACT Abstract Novel synthesis of water-soluble biogenic CdS nanotriangles at room temperature... more ABSTRACT Abstract Novel synthesis of water-soluble biogenic CdS nanotriangles at room temperature using fenugreek (Trigonella foenum graecum) aqueous seed extract via a facile, green and environmentally benign route is being reported. The X-ray diffraction (XRD) analysis confirmed that CdS nanotriangles were of the wurtzite structure. Fourier Transform Infrared (FT-IR) spectrum showed the role of fenugreek seed extract in the formation of CdS nanotriangles. The optical absorption studies reveal that CdS nanotriangles exhibit strong quantum confinement effect as the optical energy band gap increased significantly compared to the bulk CdS. The transmission electron microscopy (TEM) image showed that the CdS nanotriangles are uniform in size and shape in the range of 53 nm.
Development of novel antidiabetic agents using various organic compounds and biomolecules has bee... more Development of novel antidiabetic agents using various organic compounds and biomolecules has been in practice for a long time. Recently, nanomaterials are also being used in antidiabetic studies for their unique properties such as small size, biocompatibility and ability to penetrate cell membrane for carrying drugs. Herein, in vivo antidiabetic activity of gold nanoparticles (AuNPs) synthesized using the antidiabetic potent plant Gymnema sylvestre R. Br on wistar albino rats has been evaluated. The formation of AuNPs and their morphology were confirmed using spectroscopic and microscopic analyses, respectively. The treatment of AuNPs has shown significant reduction in blood glucose level on diabetic rats. AuNPs were also tested for its anti-inflammatory effect by estimating the serum levels of tumor necrosis factor-alpha (TNF-␣), interleukin-6 (IL-6) and high-sensitive C-reactive protein (CRP).
Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of ... more Biofunctionalized gold nanoparticles (AuNPs) play an important role in design and development of nanomedicine. Synthesis of AuNPs from biogenic materials is environmentally benign and possesses high bacterial inhibition and bactericidal properties. In the present study, blue green alga Spirulina platensis protein mediated synthesis of AuNPs and its antibacterial activity against Gram positive bacteria is discussed. AuNPs were characterized using Ultraviolet-visible (UV-vis) spectroscopy, Fluorescence spectroscopy, Fourier Transform-Infrared (FTIR) spectroscopy, Raman spectroscopy, High Resolution-Transmission Electron Microscopy (HR-TEM) and Energy Dispersive X-ray analysis (EDAX). Stable, well defined AuNPs of smaller and uniform shape with an average size of~5 nm were obtained. The antibacterial efficacy of protein functionalized AuNPs were tested against Gram positive organisms Bacillus subtilis and Staphylococcus aureus.
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