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1.
Sensors (Basel) ; 24(2)2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38257671

RESUMO

Tracking human operators working in the vicinity of collaborative robots can improve the design of safety architecture, ergonomics, and the execution of assembly tasks in a human-robot collaboration scenario. Three commercial spatial computation kits were used along with their Software Development Kits that provide various real-time functionalities to track human poses. The paper explored the possibility of combining the capabilities of different hardware systems and software frameworks that may lead to better performance and accuracy in detecting the human pose in collaborative robotic applications. This study assessed their performance in two different human poses at six depth levels, comparing the raw data and noise-reducing filtered data. In addition, a laser measurement device was employed as a ground truth indicator, together with the average Root Mean Square Error as an error metric. The obtained results were analysed and compared in terms of positional accuracy and repeatability, indicating the dependence of the sensors' performance on the tracking distance. A Kalman-based filter was applied to fuse the human skeleton data and then to reconstruct the operator's poses considering their performance in different distance zones. The results indicated that at a distance less than 3 m, Microsoft Azure Kinect demonstrated better tracking performance, followed by Intel RealSense D455 and Stereolabs ZED2, while at ranges higher than 3 m, ZED2 had superior tracking performance.


Assuntos
Dispositivos Ópticos , Robótica , Humanos , Ergonomia , Esqueleto , Software
2.
Transfus Apher Sci ; 62(6): 103811, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37730446

RESUMO

CuSO4 (Copper sulphate) poisoning though rare, is associated with high mortality. It involves multiple organ systems and if not dealt with promptly can lead to death. Supportive care and chelation therapy along with TPE (therapeutic plasma exchange), whole blood exchange or red cell exchange can be employed in management. We report such a case where swift clinical improvement was seen after TPE.


Assuntos
Sulfato de Cobre , Troca Plasmática , Humanos , Sulfatos , Plasmaferese
3.
J Electrocardiol ; 62: 107-109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841866

RESUMO

Brugada phenocopy is a brugada-like pattern in ECG seen in some diseases without an inherited channelopathy. The causes of brugada phenocopy are usually reversible. Once the reversible condition resolves, the ECG pattern disappears. There are many conditions that cause brugada phenocopy like myocardial infarction, hyperkalemia etc. Here we report a case of brugada phenocopy induced by consumption of yellow oleander seeds (T. Peruviana).


Assuntos
Síndrome de Brugada , Infarto do Miocárdio , Nerium , Síndrome de Brugada/induzido quimicamente , Síndrome de Brugada/diagnóstico , Eletrocardiografia , Humanos , Sementes
4.
J Org Chem ; 84(22): 14670-14678, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31603325

RESUMO

Oxidopyrylium ylides are useful intermediates in synthetic organic chemistry because of their capability of forming structurally complex cycloadducts. They can also self-dimerize via [5 + 3] cycloaddition, which is an oft-reported side reaction that can negatively impact [5 + 2] cycloadduct yields and efficiency. In select instances, these dimers can be synthesized and used as the source of oxidopyrylium ylide, although the generality of this process remains unclear. Thus, how the substitution pattern governs both dimerization and cycloaddition reactions is of fundamental interest to probe factors to regulate them. The following manuscript details our findings that maltol-derived oxidopyrylium ylides (i.e., with ortho methyl substitution relative to oxide) can be trapped prior to dimerization more efficiently than the regioisomeric allomaltol-derived ylide (i.e., with a para methyl substitution relative to oxide). Density functional theory studies provide evidence in support of a sterically (kinetically) controlled mechanism, whereby gauche interactions between appendages of the approaching maltol-derived ylides are privileged by higher barriers for dimerization and thus are readily intercepted by dipolarophiles via [5 + 2] cycloadditions.


Assuntos
Compostos Bicíclicos com Pontes/síntese química , Pironas/química , Tropolona/síntese química , Compostos Bicíclicos com Pontes/química , Reação de Cicloadição , Dimerização , Cinética , Estrutura Molecular , Tropolona/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-28167553

RESUMO

Cryptococcus neoformans is a pathogen that is common in immunosuppressed patients. It can be treated with amphotericin B and fluconazole, but the mortality rate remains 15 to 30%. Thus, novel and more effective anticryptococcal therapies are needed. The troponoids are based on natural products isolated from western red cedar, and have a broad range of antimicrobial activities. Extracts of western red cedar inhibit the growth of several fungal species, but neither western red cedar extracts nor troponoid derivatives have been tested against C. neoformans We screened 56 troponoids for their ability to inhibit C. neoformans growth and to assess whether they may be attractive candidates for development into anticryptococcal drugs. We determined MICs at which the compounds inhibited 80% of cryptococcal growth relative to vehicle-treated controls and identified 12 compounds with MICs ranging from 0.2 to 15 µM. We screened compounds with MICs of ≤20 µM for cytotoxicity in liver hepatoma cells. Fifty percent cytotoxicity values (CC50s) ranged from 4 to >100 µM. The therapeutic indexes (TI, CC50/MIC) for most of the troponoids were fairly low, with most being <8. However, two compounds had TI values that were >8, including a tropone with a TI of >300. These tropones are fungicidal and are not antagonistic when used in combination with fluconazole or amphotericin B. Inhibition by these two tropones remains unchanged under conditions favoring cryptococcal capsule formation. These data support the hypothesis that troponoids may be a productive scaffold for the development of novel anticryptococcal therapies.


Assuntos
Antifúngicos/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Anfotericina B/farmacologia , Cryptococcus neoformans/crescimento & desenvolvimento , Fluconazol/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Tropolona/farmacologia
7.
Indian J Hematol Blood Transfus ; 40(3): 454-459, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39011241

RESUMO

Preparing maximum platelets from all daily blood donations is essential to maintain adequate stock of platelets that may be feasible by storing buffy coat overnight. The overnight stored buffy coat method is prevalent in Europe and was not studied much in India. Therefore, a comparative study was planned to compare RDPs prepared from fresh and overnight stored buffy coat methods. In this study total of eighty RDPs were prepared. Forty RDPs were prepared by each method by matching similar platelet counts in whole blood in pairs and avoiding other bias. Quality analysis was done in various hematological, biochemical, metabolic, and activation parameters and with National guideline. RDPs prepared by the overnight stored buffy coat method had statistically higher mean platelet counts, lesser WBC contamination, lesser glucose concentration, higher lactate concentration, lesser pH, and higher MPV & PDW than RDPs prepared by the fresh buffy coat method. P selectin levels were lesser in the overnight stored category. The platelet yield in RDPs (extraction from the whole blood) was more in the overnight stored category. Compared with the national guideline, 87.5% of units passed the quality criteria in the fresh category compared to 100% of units in the overnight category. RDPs prepared from overnight stored buffy coats not only had better quality parameters but also were in a less activated state. Because of better quality and feasibility in blood centers, the overnight stored buffy coat method may also be used along with the traditional preparation method.

8.
Transfus Clin Biol ; 31(1): 36-40, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37944664

RESUMO

Hyperleukocytosis in leukemic patients may cause tumour lysis syndrome, disseminated intravascular coagulopathy, and leukostasis, resulting in decreased tissue perfusion and increasing the risk of mortality. Since the myeloid blasts are larger than lymphoid blasts and are less deformable, complications of leukostasis are seen more frequently in myeloid leukemia. Priapism is a less common complication associated with leukostasis in leukaemia patients that should be treated as soon as possible to avoid ischemic injuries. Although chemotherapeutic drugs such as hydroxyurea and imatinib are used to treat hyperleukocytosis in CML patients, leukocytapheresis (LCP) can achieve rapid cytoreduction. Prophylactic LCP could not offer any advantage over aggressive chemotherapy, but therapeutic leukocyte depletion has a proven role in patients having symptomatic leukostasis due to high tumour burden. Three patients with ischaemic priapism were reported at our institute's emergency department, where detumescence could not be achieved by distal shunting or aspiration with phenylephrine instillation. The procedure of therapeutic LCP was performed in all three patients on an emergency basis, which resolved painful priapism by rapid cytoreduction.


Assuntos
Leucemia Mieloide , Leucostasia , Priapismo , Masculino , Humanos , Priapismo/terapia , Priapismo/complicações , Leucaférese/métodos , Leucostasia/terapia , Leucostasia/complicações , Centros de Atenção Terciária
9.
Cureus ; 16(5): e60895, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38836152

RESUMO

Background Of late, the interest in accelerated treatment protocols in repetitive transcranial magnetic stimulation (TMS) for the treatment of depression and obsessive-compulsive disorder (OCD) has been gaining momentum. Studies have already found that the patterned theta burst stimulation is non-inferior to the standard high-frequency stimulation in treating depression. The objective of the present study was to evaluate the clinical efficacy of a customized accelerated combination TMS naturalistic setting. Methods Retrospective analysis of pre and post-deep repetitive TMS responses in depression and OCD patients was performed. About 391 Depression and 239 OCD patients' data was analyzed. Customized treatment protocols consisted of twice daily high-frequency stimulations intervened by one theta burst stimulation. The outcome measures were a day six score in depression and a day 10 score in OCD, compared to day one baseline scores. Results The overall response rate in depression was 60.86%, estimated as a >50% reduction in the Hamilton Depression Rating Scale (HAM-D) 21 items score, and 62.76% in OCD, estimated as a >35% reduction in the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score. The mean reduction of YBOCS and HAM-D was statistically significant at p<0.0001 (Mann-Whitney U test statistic=9442.5, z=12.66 for YBOCS and 16673.5, z=18.92 for HAM-D). Corresponding effect size estimations revealed Cohen's d value of 1.40 and 1.59, respectively. Conclusions The response rates achieved at day six and day 10 in depression and OCD, respectively, were comparable to previous studies employing standard treatment protocols. The accelerated protocol produced satisfactory short-term clinical outcomes that were effective in the early management of the illness without any serious adverse effects.

10.
J Am Chem Soc ; 135(1): 347-53, 2013 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-23237487

RESUMO

Iron-based rechargeable batteries, because of their low cost, eco-friendliness, and durability, are extremely attractive for large-scale energy storage. A principal challenge in the deployment of these batteries is their relatively low electrical efficiency. The low efficiency is due to parasitic hydrogen evolution that occurs on the iron electrode during charging and idle stand. In this study, we demonstrate for the first time that linear alkanethiols are very effective in suppressing hydrogen evolution on alkaline iron battery electrodes. The alkanethiols form self-assembled monolayers on the iron electrodes. The degree of suppression of hydrogen evolution by the alkanethiols was found to be greater than 90%, and the effectiveness of the alkanethiol increased with the chain length. Through steady-state potentiostatic polarization studies and impedance measurements on high-purity iron disk electrodes, we show that the self-assembly of alkanethiols suppressed the parasitic reaction by reducing the interfacial area available for the electrochemical reaction. We have modeled the effect of chain length of the alkanethiol on the surface coverage, charge-transfer resistance, and double-layer capacitance of the interface using a simple model that also yields a value for the interchain interaction energy. We have verified the improvement in charging efficiency resulting from the use of the alkanethiols in practical rechargeable iron battery electrodes. The results of battery tests indicate that alkanethiols yield among the highest faradaic efficiencies reported for the rechargeable iron electrodes, enabling the prospect of a large-scale energy storage solution based on low-cost iron-based rechargeable batteries.

11.
Angew Chem Int Ed Engl ; 51(28): 7016-9, 2012 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-22730316

RESUMO

Intramolecular redox reaction: heating N-alkyl, N-allyl-, and N-benzyl-substituted S-alkenyl sulfoximines under appropriate conditions results in the formation of NH-S-alkyl sulfoximines. The intramolecular redox reaction involves a hydride transfer that occurs by a 6-endo-trig process. The intermediates in the reaction can also give access to four- and six-membered heterocyclic rings and a new class of chiral dienes.

12.
J Emerg Trauma Shock ; 15(1): 66-69, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431478

RESUMO

Chest pain is one of the most common presenting complaints in the emergency department. Interpreting a 12-lead electrocardiography (ECG) for evidence of ischemia is always challenging. Frank ECG changes such as ST-segment elevation and ST-segment depression can be easily identified by emergency physicians. However, identifying subtle or early features of ACS in the 12-lead ECG is essential in preventing significant mortality and morbidity from ACS. In the following case series, we describe five of the subtle/early ECG changes of ACS, namely (1) T-wave inversion in lead aVL; (2) terminal QRS distortion; (3) hyperacute T-waves; (4) negative U-waves in precordial leads; and (5) loss of precordial T-wave balance. In all these cases, the initial 12-lead ECG showed only subtle/early ECG changes which were followed up with serial ECGs which progressed to STEMI.

13.
Bioresour Technol ; 344(Pt B): 126418, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34838962

RESUMO

This short communication investigated biodiesel production from Euglena Sanguineamicroalgaeand custard appleusing nano CaO as a heterogeneous catalyst. Different solvents were used to extract the oil at a fixed speed, time, and temperature for the samples to estimate the optimized oil yield%. The catalyst was synthesized by sol gel method in nano-scale. It was further characterized by FTIR spectroscopy, SEM, and XRD. The algal oil was pre-treated and trans-esterified with a catalyst to produce alkyl esters. The optimized process variables were determined using response surface methodology by varying parameters such as methanol to oil ratio and catalyst weight% for algal bio-oil and MeOH to oil ratio, time, and catalyst weight% for seed oil. The GC-MS was done to characterize the presence of biodiesel. Kinetic studies were done for the optimized condition for the algal oil and seed oil and it follows the pseudo-first order reaction.


Assuntos
Annona , Euglena , Biocombustíveis , Catálise , Esterificação , Cinética , Óleos de Plantas
14.
Nucleic Acids Res ; 36(2): 511-9, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18048416

RESUMO

Nucleases play important roles in DNA synthesis, recombination and repair. We have previously shown that human exonuclease 1 (hEXO1) is phosphorylated in response to agents stalling DNA replication and that hEXO1 consequently undergoes ubiquitination and degradation in a proteasome-dependent manner. In the present study, we have addressed the identity of the pathway transducing stalled-replication signals to hEXO1. Using chemical inhibitors, RNA interference, ATM- and ATR-deficient cell lines we have concluded that hEXO1 phosphorylation is ATR-dependent. By means of mass spectrometry, we have identified the sites of phosphorylation in hEXO1 in undamaged cells and in cells treated with hydroxyurea (HU). hEXO1 is phosphorylated at nine basal sites and three additional sites are induced by HU treatment. Analysis of single- and multiple-point mutants revealed that mutation to Ala of the three HU-induced sites of phosphorylation partially rescued HU-dependent degradation of hEXO1 and additionally stabilized the protein in non-treated cells. We have raised an antibody to pS(714), an HU-induced site of the S/T-Q type, and we provide evidence that S(714) is phosphorylated upon HU but not IR treatment. The antibody may be a useful tool to monitor signal transduction events triggered by stalled DNA replication.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Replicação do DNA , Exodesoxirribonucleases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Anticorpos Fosfo-Específicos/imunologia , Proteínas Mutadas de Ataxia Telangiectasia , Linhagem Celular , Enzimas Reparadoras do DNA/química , Enzimas Reparadoras do DNA/genética , Replicação do DNA/efeitos dos fármacos , Estabilidade Enzimática , Exodesoxirribonucleases/química , Exodesoxirribonucleases/genética , Células HeLa , Humanos , Hidroxiureia/farmacologia , Camundongos , Mutação , Fosforilação , Fosfosserina/imunologia , Transdução de Sinais
15.
J Emerg Trauma Shock ; 13(4): 312-316, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33897151

RESUMO

One of the rare causes of diffuse T-wave inversion (TWI) in electrocardiogram (ECG) is memory T-waves. This should be considered among the differentials of diffuse TWI in ECG of patients presenting to the emergency department (ED), especially when they have previous episodes of ventricular tachycardia (VT) or pacemaker implantation or Wolff-Parkinson-White syndrome. These TWIs are benign and do not require any treatment. However, it is of paramount importance for the emergency physician to differentiate it from ischemia-related T-wave changes. In the following case series, we report three cases of memory T-waves. Two of the cases had TWI in leads II, III, aVF, and V3 to V6 following reversion of VT. The other patient, with a VVI (Left ventricle paced, Left ventricle sensed, Inhibition to sensing) pacemaker, had memory T-waves in the ECG taken during normal sinus rhythm. In all the three patients, we considered memory T-waves to be the possible cause of TWI. The electrocardiographic diagnostic criteria for memory T-waves are positive T in lead aVL and positive/isoelectric T in the lead I; and precordial TWI >inferior TWI. These criteria are 92% sensitive and 100% specific. In the following case series, we also provide an algorithmic approach for patients with suspected memory T-waves in their 12-lead ECG when they present to the ED.

16.
Medchemcomm ; 10(7): 1173-1176, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31391890

RESUMO

We previously reported that troponoid compounds profoundly inhibit replication of herpes simplex virus (HSV)-1 and HSV-2 in cell culture, including acyclovir-resistant mutants. Synthesis of 26 alpha-hydroxylated tropolones (αHTs) led to a preliminary structure-activity relationship highlighting the potency of bi-phenyl side chains. Here, we explore the structure-activity relationship in more detail, with a focus on various biaryl and other lipophilic molecules. Along with our prior structure-function analysis, we present a refined structure-activity relationship that reveals the importance of the lipophilicity and nature of the side chain for potent anti-HSV-1 activity in cells. We expect this new information will help guide future optimization of αHTs as HSV antivirals.

17.
Bioelectrochemistry ; 72(2): 149-54, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18294928

RESUMO

Electrochemical impedance spectroscopy (EIS) has been used to determine several electrochemical properties of the anode and cathode of a mediator-less microbial fuel cell (MFC) under different operational conditions. These operational conditions included a system with and without the bacterial catalyst and EIS measurements at the open-circuit potential of the anode and the cathode or at an applied cell voltage. In all cases the impedance spectra followed a simple one-time-constant model (OTCM) in which the solution resistance is in series with a parallel combination of the polarization resistance and the electrode capacitance. Analysis of the impedance spectra showed that addition of Shewanella oneidensis MR-1 to a solution of buffer and lactate greatly increased the rate of the lactate oxidation at the anode under open-circuit conditions. The large decrease of open-circuit potential of the anode increased the cell voltage of the MFC and its power output. Measurements of impedance spectra for the MFC at different cell voltages resulted in determining the internal resistance (R(int)) of the MFC and it was found that R(int) is a function of cell voltage. Additionally, R(int) was equal to R(ext) at the cell voltage corresponding to maximum power, where R(ext) is the external resistance that must be applied across the circuit to obtain the maximum power output.


Assuntos
Fontes de Energia Bioelétrica , Análise Espectral/métodos , Impedância Elétrica , Eletroquímica
18.
Antiviral Res ; 144: 164-172, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28633989

RESUMO

Chronic Hepatitis B virus (HBV) infection is a major worldwide public health problem. Current direct-acting anti-HBV drugs target the HBV DNA polymerase activity, but the equally essential viral ribonuclease H (RNaseH) activity is unexploited as a drug target. Previously, we reported that α-hydroxytropolone compounds can inhibit the HBV RNaseH and block viral replication. Subsequently, we found that our biochemical RNaseH assay underreports efficacy of the α-hydroxytropolones against HBV replication. Therefore, we conducted a structure-activity analysis of 59 troponoids against HBV replication in cell culture. These studies revealed that antiviral efficacy is diminished by larger substitutions on the tropolone ring, identified key components in the substitutions needed for high efficacy, and revealed that cytotoxicity correlates with increased lipophilicity of the α-hydroxytropolones. These data provide key guidance for further optimization of the α-hydroxytropolone scaffold as novel HBV RNaseH inhibitors.


Assuntos
Antivirais/farmacologia , Inibidores Enzimáticos/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/enzimologia , Ribonuclease H/antagonistas & inibidores , Tropolona/análogos & derivados , Tropolona/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Vírus da Hepatite B/fisiologia , Humanos , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
19.
J Family Med Prim Care ; 3(3): 255-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25374865

RESUMO

BACKGROUND: Settings-based approach for health promotion includes conducting risk factor surveillance as one of its component. It was aimed to estimate the prevalence of CVD risk factors among group C employees of tertiary care hospital in south India. MATERIALS AND METHODS: A cross-sectional survey was conducted among 400 group C employees aged ≥20 years using the WHO "STEPwise approach to surveillance of non-communicable diseases" (STEPS) methodology. Standardized international protocols were used to measure behavioral risk factors (smoking, alcohol consumption, fruit and vegetable consumption, physical activity) and physical characteristics (weight, waist and hip circumferences, height, and blood pressure). Multivariate analysis was done to predict the factors, which carry independent risk of hypertension. Risk factor profiling of the staff was done using WHO/ISH risk prediction chart to calculate the 10-year risk of a fatal or non-fatal major cardiovascular events (myocardial infarction or stroke), according to age, gender, blood pressure, smoking status, and presence or absence of diabetes mellitus. RESULTS: Mean age in years was 40.9 (±10.4), and men constituted 81.3% of study population. Prevalence of major cardiovascular risk factors was as follows: Current smokers 12.3% men, regular alcohol intake 33.2% among men, overweight (≥23 kg/m(2)) 74.5%, central obesity 78.7%, hypertension 38.8%, and history of diabetes mellitus 13.2%. Age, gender, physical inactivity, obesity, and family history of hypertension were found to be independently associated with hypertension. Four percent participants had a >10% risk of developing CVD in next 10 years. CONCLUSION: The prevalence of CVD risk factors is high in the sample population. Employee wellness program should be started in the institute to combat the burden of cardiovascular diseases.

20.
Bioresour Technol ; 114: 308-13, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22446049

RESUMO

A floating microbial fuel cell (FMFC) has been designed and its performance has been evaluated for 153 days. The power output gradually increased to a maximum value of 390 mW/m(3) at 125 days. The polarization resistance of the anode (R(p)(a)) changed with operating time reaching a minimum value at 125 days, while the polarization resistance of the cathode (R(p)(c)) was relatively constant and much smaller than R(p)(a). It has been demonstrated that the observed changes of the internal resistance (R(int)) and the maximum power (P(max)) with exposure time were mainly due to the changes of R(p)(a). Compared with sediment MFCs for which the anode is embedded in marine or river sediments, the application of the FMFC, which could be installed in a buoy, is not limited by the depth of the ocean. The FMFC has the potential to supply electricity to low-power consuming electronic devices at remote locations.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Eletrodos , Transferência de Energia , Navios , Microbiologia da Água , Desenho de Equipamento , Análise de Falha de Equipamento
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