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1.
ScientificWorldJournal ; 2015: 174512, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26759829

RESUMEN

Wireless Body Area Network (WBAN) is effectively used in healthcare to increase the value of the patient's life and also the value of healthcare services. The biosensor based approach in medical care system makes it difficult to respond to the patients with minimal response time. The medical care unit does not deploy the accessing of ubiquitous broadband connections full time and hence the level of security will not be high always. The security issue also arises in monitoring the user body function records. Most of the systems on the Wireless Body Area Network are not effective in facing the security deployment issues. To access the patient's information with higher security on WBAN, Game Theory with Stackelberg Security Equilibrium (GTSSE) is proposed in this paper. GTSSE mechanism takes all the players into account. The patients are monitored by placing the power position authority initially. The position authority in GTSSE is the organizer and all the other players react to the organizer decision. Based on our proposed approach, experiment has been conducted on factors such as security ratio based on patient's health information, system flexibility level, energy consumption rate, and information loss rate. Stackelberg Security considerably improves the strength of solution with higher security.


Asunto(s)
Tecnología de Sensores Remotos/métodos , Telemedicina/métodos , Teoría del Juego
2.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 3): o358, 2013 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23476548

RESUMEN

The title mol-ecule, C19H12S2O2, lies on a twofold rotation axis. The thio-chromonone unit is essentially planar, with a maximum deviation of 0.0491 (14) Å. The dihedral angle between the thio-chromenone ring systems is 64.48 (4)°. In the crystal, there are weak π-π stacking inter-actions, with a centroid-centroid distance of 3.7147 (9) Å.

3.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 5): o763, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23723909

RESUMEN

In the racemic title compound, C21H18O4, the chromone ring is essentially planar [maximum deviation from the least-squares plane = 0.026 (3) Å], with a dihedral angle of 78.18 (12)° between the benzene rings of the chromanone and chromenone moieties. In the crystal, there are weak π-π stacking inter-actions [minimum ring centroid separation = 3.9286 (17) Å].

4.
Heliyon ; 9(8): e19055, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37636351

RESUMEN

The temperature effect on the wear behaviour of EV31A Mg alloy during dry sliding wear was investigated. Wear tests were carried out at 50, 100, 150, 200, and 250 °C using a standard load of 10 N and a sliding distance of 1000 m. Weight loss method was used to calculate the wear rate. Optical microscopy was used to examine the microstructure of the EV31A alloy. FE-SEM with EDS analysis was used to investigate the wear morphology, and XRD analysis was performed both before and after the wear test. A high wear coefficient (K) value (more than 10-4) indicates extreme wear for EV31A in all the scenarios. T4 EV31A had a maximum wear rate of 20.2 mg at 150 °C. The as-cast EV31A alloy exhibits an excellent wear rate at the price of mechanical properties under all test scenarios. Wear resistance is improved by Nd and Zr oxides, although Mg and Gd oxides have little effect. Zn has no effect on the wear behaviour of the EV31A. In as-cast, T4, and T6 heat-treated conditions, the EV31A alloy exhibits delamination (abrasive wear), oxide development (corrosive wear), and delamination mixed with plastic deformation (adhesive wear). A Three-layered ANN and adapted Fine Gaussian SVM predicted tribological characteristics. In ANN prediction, the maximum R2 was 0.99 for CoF and 0.89 for wear rate, respectively. Despite the fact that the study's normal load is constant, machine learning models allow to deduce that temperature and normal load are the main influential parameters in CoF and wear rate, respectively.

5.
Nanomaterials (Basel) ; 12(13)2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35808014

RESUMEN

This review paper gives an insight into the microstructural, mechanical, biological, and corrosion resistance of spark plasma sintered magnesium (Mg) composites. Mg has a mechanical property similar to natural human bones as well as biodegradable and biocompatible properties. Furthermore, Mg is considered a potential material for structural and biomedical applications. However, its high affinity toward oxygen leads to oxidation of the material. Various researchers optimize the material composition, processing techniques, and surface modifications to overcome this issue. In this review, effort has been made to explore the role of process techniques, especially applying a typical powder metallurgy process and the sintering technique called spark plasma sintering (SPS) in the processing of Mg composites. The effect of reinforcement material on Mg composites is illustrated well. The reinforcement's homogeneity, size, and shape affect the mechanical properties of Mg composites. The evidence shows that Mg composites exhibit better corrosion resistance, as the reinforcement act as a cathode in a Mg matrix. However, in most cases, a localized corrosion phenomenon is observed. The Mg composite's high corrosion rate has adversely affected cell viability and promotes cytotoxicity. The reinforcement of bioactive material to the Mg matrix is a potential method to enhance the corrosion resistance and biocompatibility of the materials. However, the impact of SPS process parameters on the final quality of the Mg composite needs to be explored.

7.
Ann R Coll Surg Engl ; 101(8): e172-e177, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31672034

RESUMEN

Intragastric balloons have been used as an invasive non-surgical treatment for obesity for over 30 years. Within the last 37 years, we have found only 27 cases reported in the literature of intestinal obstruction caused by a migrated intragastric balloon. We report the laparoscopic management of such a case and make observations from similar case presentations published in the literature. A 26-year-old woman had an intragastric balloon placed endoscopically for weight control 13 months previously. She presented to the emergency department with a four-day history of intermittent abdominal cramps and vomiting. Contrast enhanced computed tomography confirmed the presence of the intragastric balloon within the small bowel. At laparoscopic retrieval, the deflated intragastric balloon was found impacted in the terminal ileum approximately 15 cm from the ileocaecal valve. The balloon was retrieved by enterotomy and primary closure of the ileum without event. The risk of balloon deflation and subsequent migration increases over time but several published cases demonstrate that this complication can occur within six months of insertion. The initial approach to the treatment of migrated intragastric balloons causing small bowel obstruction should be determined by the location of impaction, severity of obstruction and the available skill set of the attending radiologist, endoscopist and/or surgeon. Balloons causing obstruction in the duodenum are likely amenable to endoscopic retrieval whereas impaction within the jejunum or ileum could be managed by percutaneous needle aspiration (in selected cases), endoscopy (double-balloon enteroscopy), laparoscopy or open surgery.


Asunto(s)
Migración de Cuerpo Extraño/cirugía , Balón Gástrico/efectos adversos , Enfermedades del Íleon/cirugía , Obstrucción Intestinal/cirugía , Laparoscopía/métodos , Adulto , Femenino , Migración de Cuerpo Extraño/diagnóstico por imagen , Migración de Cuerpo Extraño/etiología , Humanos , Enfermedades del Íleon/diagnóstico por imagen , Enfermedades del Íleon/etiología , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Obesidad/cirugía , Tomografía Computarizada por Rayos X
8.
J Biomater Appl ; 30(2): 239-53, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25855682

RESUMEN

Off-the-shelf availability of tissue-engineered skin constructs, tailored by different combinations of reagents to produce a highly preserved biological matrix is often the only means to help patients suffering skin damage. This study assessed the effect of five different decellularisation methods on porcine dermal scaffolds with regard to matrix composition, biomechanical strength, and cytotoxicity using an in vitro biocompatibility assay. Results demonstrated that four out of the five tested decellularisation protocols were efficient in producing acellular scaffolds. Nevertheless, decellularisation method using osmotic shock without enzymatic digestion showed to be efficient not only in removing cellular material and debris from dermal scaffolds but was also beneficial in the preservation of extracellular matrix components (glycosaminoglycans and collagen). Histological assessment revealed that the dermal architecture of coarse collagen bundles was preserved. Examinations by scanning electron microscopy and transmission electron microscopy showed that the arrangement and ultrastructure of collagen fibrils in the scaffolds were retained following non-enzymatic method of decellularisation and also after collagen crosslinking using genipin. Moreover, this decellularised scaffold was not only shown to be biologically compatible when co-cultured with bone marrow-derived mesenchymal stem cells and fibroblasts, but also stimulated the cells to release trophic factors essential for tissue regeneration.


Asunto(s)
Dermis Acelular , Materiales Biocompatibles , Andamios del Tejido , Animales , Microscopía Electrónica de Rastreo , Porcinos
9.
ScientificWorldJournal ; 4: 1046-54, 2004 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-15632983

RESUMEN

Recently, free radical-induced tissue damage is implicated in the nonsteroidal anti-inflammatory drugs (NSAIDs)-involved gastric mucosal lesion. Administration of taurine, an endogenous antioxidant, is reported to be beneficial in various clinical conditions. Therefore, we decided to study the protective effect of taurine in ibuprofen-induced gastropathy and the effects of administration of taurine on the endogenous antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX), and reduced glutathione (GSH) of stomach. In rats, administration of taurine orally for three consecutive days (250 mg/kg body weight) protected the gastric mucosa from ibuprofen-induced, acute gastric mucosal lesion. In ibuprofen-treated rats, the lipid peroxidation measured as thiobarbituric acid reactive substances (TBARS), a marker for free radical-induced tissue damage, is also significantly decreased by taurine. Ibuprofen treatment resulted in a significant increase in the activities of total SOD, manganese SOD (Mn-SOD), and GPX and reduced GSH. Taurine administration in ibuprofen-treated rats also showed a significant increase in the activities of the antioxidant enzymes namely total SOD, Mn-SOD, GPX, CAT, and the level of reduced GSH. The activity of copper-zinc SOD enzyme (Cu-Zn SOD) is not affected by ibuprofen or taurine. There is no temporal relation between the antioxidant status of the stomach and the tissue damage following oral administration of ibuprofen or taurine.


Asunto(s)
Antioxidantes/metabolismo , Mucosa Gástrica/efectos de los fármacos , Úlcera Gástrica/prevención & control , Taurina/uso terapéutico , Animales , Antiinflamatorios no Esteroideos , Catalasa/metabolismo , Femenino , Mucosa Gástrica/patología , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Ibuprofeno , Peroxidación de Lípido/efectos de los fármacos , Masculino , Ratas , Ratas Wistar , Úlcera Gástrica/inducido químicamente , Superóxido Dismutasa/metabolismo
10.
BMJ Open ; 2(3)2012.
Artículo en Inglés | MEDLINE | ID: mdl-22586283

RESUMEN

OBJECTIVES: This study was aimed to evaluate the efficacy and tolerability of bisoprolol, in Indian patients diagnosed with stage I essential hypertension as first-line drug. DESIGN: This was an open-label, phase IV, multicentric prospective study. SETTINGS: 239 outpatient centres across India. PARTICIPANTS: After ethical approval, patients who were willing to sign informed consent, who are newly diagnosed with JNC VII stage I essential hypertension (systolic blood pressure 140-159 mm Hg or diastolic blood pressure 90-99 mm Hg) and who are prescribed bisoprolol were enrolled in the study. Patients with significant organ disease or complications, women of childbearing age refusing reliable contraceptive method, patients with known contraindications (like symptomatic bradycardia, significant atrioventricular blockade, sick sinus syndrome) and patients with known hypersensitivity reactions to bisoprolol and unwilling patients were excluded. PRIMARY AND SECONDARY OUTCOMES MEASURES: The primary outcome measure was percentage of patients achieving blood pressure (BP) ≤140/90 mm Hg at the end of 12 weeks, while multiple secondary outcome measures were assessed. RESULTS: Of 2418 patients screened, 2161 patients were recruited (66.64% men, mean age 51.7±9.8 years, smokers 19.19%) and 2131 (96.44%) patients achieved BP control. There was significant reduction in systolic blood pressure (-25.29; SD: 13.22 mm Hg), diastolic blood pressure (-14.14; SD: 7.67 mm Hg) and heart rate (-12/min; SD: 6.15) compared with baseline (all p values <0.05). The median dose of bisoprolol and average period required for the response were 5 mg/day and 33 days, respectively. Bisoprolol was found to be well tolerated in the patients up to 10 mg/day. A total of 1.9% patients showed adverse events, which were mild to moderate in severity without any severe adverse event. None required treatment withdrawal. CONCLUSION: Bisoprolol is an effective and safe option to control BP. Thus, it can be used as one of the first-line antihypertensive in Indian patients.

12.
Curr Protein Pept Sci ; 10(4): 308-38, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19689355

RESUMEN

Milk and colostrum is a rich source of proteins/peptides which have crucial roles in both neonates and adults. Milk bioactive proteins and peptides are potential health-enhancing nutraceuticals for food. Many bioactive peptides/proteins may be used as nutraceuticals, for example, in the treatment of cancer, asthma, diarrhea, hypertension, thrombosis, dental diseases, as well as mineral malabsorption, and immunodeficiency. The following components of milk are of particular interest in the recent years: 1) Lactoferrin [Lf] has antibacterial, antifungal, antiviral, antiparasite and antitumor activities and accelerates immunomodulatory properties. Lf is a potent inhibitor for several enveloped and naked viruses, such as rotavirus, enterovirus and adenovirus. Lf is resistant to tryptic digestion and breast-fed infants excrete high levels of faecal Lf, so that its effect on viruses replicating in the gastrointestinal tract is of great interest. 2) Casein has been protective in experimental bacteremia by eliciting myelopoiesis. Casein hydrolyzates were also protective in diabetic animals, reduced the tumor growth and diminished colicky symptoms in infants. 3) A Proline rich polypeptide [PRP] revealed variety of immunotropic functions, including promotion of T-cell activation and inhibition of autoimmune disorders such as multiple sclerosis. 4) alpha-Lactalbumin [LA] demonstrates antiviral, antitumor and anti-stress properties. 5) Lactoperoxidase shows antibacterial properties. 6) Lysozyme is effective in treatment of periodentitis and prevention of tooth decay. Taken together, milk-derived proteins and peptides are bio-available and safe for the prevention and treatment of various disorders in humans and may play a complementary [natural agents] rather than a substitutional role to the toxic synthetic pharmacological drugs.


Asunto(s)
Biotecnología/tendencias , Salud , Proteínas de la Leche/química , Proteínas de la Leche/metabolismo , Animales , Biotecnología/métodos , Humanos , Leche/química , Leche/metabolismo , Proteínas de la Leche/farmacología , Proteínas de la Leche/uso terapéutico , Péptidos/química , Péptidos/metabolismo , Péptidos/farmacología
13.
J Org Chem ; 72(15): 5867-9, 2007 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-17590047

RESUMEN

Highly deactivated aromatic compounds were smoothly monobrominated by treatment with N-bromosuccinimide (NBS) in concentrated H2SO4 medium affording the corresponding bromo derivatives in good yields. Mild reaction conditions and simple workup provides a practical and commercially viable route for the synthesis of bromo compounds of deactivated aromatics.


Asunto(s)
Bromo/química , Compuestos Orgánicos/química
14.
Ann Neurol ; 9(2): 194-7, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7235636

RESUMEN

A new form of abnormal spontaneous eye movement termed inverse ocular bobbing is described. It consists of a slow downward eye movement followed by delayed quick return upward to midposition. It is contrasted with other types of abnormal vertical eye movements.


Asunto(s)
Movimientos Oculares , Trastornos del Movimiento/diagnóstico , Adulto , Anciano , Encefalopatías/complicaciones , Encefalopatías/diagnóstico , Hemorragia Cerebral/complicaciones , Femenino , Hematoma/complicaciones , Humanos , Síndrome de Secreción Inadecuada de ADH/complicaciones , Masculino , Trastornos del Movimiento/etiología , Estado Epiléptico/complicaciones , Síndrome , Desequilibrio Hidroelectrolítico/complicaciones
15.
Ann Neurol ; 5(3): 271-87, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-443760

RESUMEN

Ten patients developed a subacute lower motor neuron syndrome as a remote effect of Hodgkin's disease or other lymphoma. The illness usually followed a benign course independent of the activity of the underlying neoplasm. Seven of the patients improved spontaneously, and 3 became neurologically normal. Two patients died of intercurrent infections related to immunosuppression. Neuropathological examination of these 2 patients and 3 previously reported cases showed prominent neuronal degeneration restricted to the anterior horns of the spinal cord and mild posterior column demyelination. Demyelination was also present in the anterior roots of our autopsied patients and was accompanied by large, hyperchromatic Schwann cells. The cause of the illness is obscure, but both radiation therapy and opportunistic infection may be contributing factors. Attempts at virus isolation have been unsuccessful. The syndrome should be distinguished from the more common direct effects of lymphoma on the nervous system, since its identification spares the patient additional, potentially harmful therapy.


Asunto(s)
Linfoma/complicaciones , Neuronas Motoras , Enfermedades Neuromusculares/etiología , Adulto , Femenino , Lóbulo Frontal/patología , Enfermedad de Hodgkin/complicaciones , Enfermedad de Hodgkin/patología , Humanos , Linfoma/patología , Masculino , Persona de Mediana Edad , Músculos/patología , Enfermedades Neuromusculares/patología , Nervios Periféricos/patología , Médula Espinal/patología , Raíces Nerviosas Espinales/patología , Síndrome
16.
Artículo en Inglés | MEDLINE | ID: mdl-7511518

RESUMEN

Human perception of 3 briefly flashed letters in a horizontal array that subtends a visual angle of 3 degrees or less is reduced by a magnetic coil (MC) pulse given, e.g., 90 msec later. Either a round or a double square MC is effective when the lower windings or central junction region, respectively, are tangential to the skull overlying calcarine cortex and symmetrical across the midline. The modeled, induced electric field has peak amplitude at the midline, but the peak spatial derivatives lie many centimeters laterally. Thus, the foveal representation near the midline is closer to the peak electric field than to its peak spatial derivatives, i.e., excitation of calcarine cortex differs from excitation of a straight nerve. With an MC pulse that induces an electric field which is substantially monophasic in amplitude, the lateral-most letter (usually the right-hand letter) in the trigram is preferentially suppressed when the electric field in the contralateral occipital lobe is directed towards the midline. Inferences from using peripheral nerve models imply that medially located bends in geniculo-calcarine or corticofugal fibers are the relevant sites of excitation in visual suppression; end excitation of fiber arborizations or apical dendrites is considered less likely. This conclusion is supported by the fact that the induced electric field polarity in paracentral lobule for optimally eliciting foot movements is opposite to that for visual suppression, the major bends occurring at different portions of the fiber trajectories in the two systems.


Asunto(s)
Campos Electromagnéticos , Magnetismo , Corteza Visual/fisiología , Humanos , Estimulación Luminosa
17.
Brain ; 114 ( Pt 6): 2505-20, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1782528

RESUMEN

A minority of normal humans experience paraesthesias (usually tingling) projected to the contralateral hand in response to individual transcranial magnetic coil (MC) pulses. The cortical source of the paraesthesias was sought by comparing their incidence with that of muscle responses to focal MC stimulation with either a figure 8 MC or with edge stimulation of a tilted round MC in 4 susceptible subjects. In all 4, paraesthesias were best felt with MC stimulation either at, or anterior to sites yielding movement, implying an initial source in precentral gyrus (and possible premotor cortex), rather than parietal cortex. In the two subjects exhibiting the strongest paraesthesias, the threshold for the paraesthesias was less than that for movement in the relaxed arm. The optimal site of the paraesthesias within the hand was usually in the digits, but differed among subjects. Motor responses and paraesthesias following a given stimulus occurred at different sites in the hand, implying that excitation of differing sets of motor cortical neurons subserved sensory and motor responses. In only one subject were the paraesthesias sufficiently reproducible to warrant interacting electrical digital and transcranial MC pulses. The data suggested that central processing of the response to the MC pulse is slowed by an antecedent digital stimulus, but the delay for perception of each type of stimulus does not greatly differ. The central sense of movement (Amassian et al., 1989a) elicited by MC stimulation of motor cortex is compared with the paraesthesias. Both are attributed to brief, high frequency discharge by motor cortical neurons accessing the perceptual system more readily than after excitation of post-central gyrus, which requires prolonged repetitive stimulation (Libet et al., 1964). Given also the normal pattern of muscle responses in the 4 subjects, their paraesthesias are best explained by a heightened sensitivity of the perceptual system to the motor cortical response to MC stimulation.


Asunto(s)
Magnetismo , Parestesia/fisiopatología , Potenciales de Acción , Adulto , Corteza Cerebral/fisiopatología , Potenciales Evocados Somatosensoriales , Femenino , Dedos , Mano , Humanos , Masculino , Persona de Mediana Edad , Corteza Motora/fisiopatología , Movimiento , Vías Nerviosas
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