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1.
Lett Appl Microbiol ; 74(4): 519-535, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34919753

RESUMEN

Plant growth-promoting bacteria (PGPB) expressing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity are widely acknowledged to have a role in mitigation of abiotic stress caused by extreme environmental conditions. Consequently, several studies have focused on the isolation of ACC deaminase positive PGPBs. However, the application of such strains in drought-prone arid regions has remained grossly under-exploited. In order to be used in arid agroecosystems, PGPBs need to have the dual capability: to express ACC deaminase and to have the ability to tolerate increased temperature and salt concentration. Conspicuously, to date, very few studies have reported about isolation and characterization of PGPBs with this kind of dual capability. Here we report the isolation of bacterial strains from rhizosphere(s) of Cyamopsis tetragonoloba, a commercial crop from arid regions of Rajasthan, India, and their characterization for ACC deaminase activity and thermohalotolerance. Isolates found positive for desired traits were subsequently assessed for plant growth promotion under simulated drought conditions. Our finding showed that although the bacterial diversity within the rhizosphere of C. tetragonoloba grown in the arid region is quite poor, multiple isolates are ACC deaminase positive. Four isolates were found to be ACC deaminase positive, thermohalotolerant, and successfully enhanced drought tolerance. These isolates were identified as strains belonging to genera Pseudomonas, Enterobacter, and Stenotrophomonas based on 16S rRNA sequence homology.


Asunto(s)
Cyamopsis , Rizosfera , Liasas de Carbono-Carbono/genética , Cyamopsis/genética , Sequías , Enterobacter/genética , India , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Microbiología del Suelo
2.
Indian J Clin Biochem ; 37(4): 449-457, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36262786

RESUMEN

Rule-out of acute myocardial infarction (AMI) in patients presenting with acute chest pain at the emergency department (ED) is a major challenge across the globe. Patients presenting very early with chest pain may provide a diagnostic challenge even when using a cardiac necrosis specific biomarker, high sensitivity troponin (hs-Tn) as they are elevated at 3-6 h after the symptom onset. Copeptin is a marker of acute hemodynamic stress which is released within few minutes of the occurrence of MI and is elevated immediately at the presentation of patients with AMI. This indicates a complementary pathophysiology and kinetics of these two biomarkers. Hence, we evaluated whether or not a protocol with combined testing of copeptin and hs-TnI at admission in patients presenting with chest pain within 6 h in low to intermediate risk and suspected ACS leads to an earlier diagnosis of AMI and thereby, aids to prevent a higher proportion of major adverse cardiac events than the current standard protocol followed in ED. A total of 148 patients as per the inclusion criterion were recruited for the study. The dual biomarker copeptin and hs-TnI allows a rule-out of AMI at presentation with a sensitivity of 100% and NPV of 99.8%. Hence, the use of dual biomarker in conjunction with clinical assessment may obviate the need for a prolonged stay in the ED and retesting hs-TnI after 2 h (for delta check) in more than two-thirds of the patients. The inclusion of these tests could have an impact on the economic burden of the ED without jeopardizing the outcome for the patient.

3.
Br J Neurosurg ; 31(4): 497-498, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26761183

RESUMEN

Malignant transformation of intracranial epidermoid cysts to squamous cell carcinoma is a rare occurrence and only a small number have been reported to date. MRI recurrence in combination with neurological decline should prompt surgery to exclude malignant transformation. Herein, we describe our experience of such a case and contribute to the evolving series within the literature.


Asunto(s)
Carcinoma de Células Escamosas/patología , Enfermedades Cerebelosas/patología , Ángulo Pontocerebeloso/patología , Quiste Epidérmico/patología , Transformación Celular Neoplásica/patología , Fosa Craneal Posterior , Quiste Epidérmico/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Neuralgia del Trigémino/etiología
4.
Br J Neurosurg ; 30(4): 464-6, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26742681

RESUMEN

The use of expensive, sophisticated, intraoperative ultrasound systems is established in cranial neurosurgery and less so in the realms of intradural spine. For units yet to acquire such costly devices, we demonstrate our experience of the readily available, anaesthetist's SonoSite™ probe in intradural spinal surgery.


Asunto(s)
Neurocirugia , Procedimientos Neuroquirúrgicos/instrumentación , Neoplasias de la Médula Espinal/cirugía , Columna Vertebral/cirugía , Anestesia , Humanos , Microcirugia/instrumentación , Ultrasonografía/instrumentación
5.
J Food Sci Technol ; 50(2): 257-65, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24425915

RESUMEN

A simple analytical heat flow model for a closed rectangular food package containing fruits or vegetables is proposed for predicting time temperature distribution during transient cooling in a controlled environment cold room. It is based on the assumption of only conductive heat transfer inside a closed food package with effective thermal properties, and convective and radiative heat transfer at the outside of the package. The effective thermal conductivity of the food package is determined by evaluating its effective thermal resistance to heat conduction in the packages. Food packages both as an infinite slab and a finite slab have been investigated. The finite slab solution has been obtained as the product of three infinite slab solutions describe in ASHRAE guide and data book. Time temperature variation has been determined and is presented graphically. The cooling rate and the half cooling time were also obtained. These predicted values, are compared with the experimentally measured values for both the finite and infinite closed packages containing oranges. An excellent agreement between them validated the simple proposed model.

6.
Nat Commun ; 14(1): 2107, 2023 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-37055427

RESUMEN

Magnetic reconnection is a key mechanism involved in solar eruptions and is also a prime possibility to heat the low corona to millions of degrees. Here, we present ultra-high-resolution extreme ultraviolet observations of persistent null-point reconnection in the corona at a scale of about 390 km over one hour observations of the Extreme-Ultraviolet Imager on board Solar Orbiter spacecraft. The observations show formation of a null-point configuration above a minor positive polarity embedded within a region of dominant negative polarity near a sunspot. The gentle phase of the persistent null-point reconnection is evidenced by sustained point-like high-temperature plasma (about 10 MK) near the null-point and constant outflow blobs not only along the outer spine but also along the fan surface. The blobs appear at a higher frequency than previously observed with an average velocity of about 80 km s-1 and life-times of about 40 s. The null-point reconnection also occurs explosively but only for 4 minutes, its coupling with a mini-filament eruption generates a spiral jet. These results suggest that magnetic reconnection, at previously unresolved scales, proceeds continually in a gentle and/or explosive way to persistently transfer mass and energy to the overlying corona.

7.
3 Biotech ; 11(9): 395, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34422536

RESUMEN

Amaranth (Amaranthus spp.) belonging to Amaranthaceae, is known as "the crop of the future" because of its incredible nutritional quality. Amaranthus spp. (> 70) have a huge diversity in terms of their plant morphology, production and nutritional quality; however, these species are not well characterized at molecular level due to unavailability of robust and reproducible molecular markers, which is essential for crop improvement programs. In the present study, 13,051 genome-wide microsatellite motifs were identified and subsequently utilized for marker development using A. hypochondriacus (L.) genome (JPXE01.1). Out of those, 1538 motifs were found with flanking sequences suitable for primer designing. Among designed primers, 225 were utilized for validation of which 119 (52.89%) primers were amplified. Cross-species transferability and evolutionary relatedness among ten species of Amaranthus (A. hypochondriacus, A. caudatus, A. retroflexus, A. cruentus, A. tricolor, A. lividus, A. hybridus, A. viridis, A. edulis, and A. dubius) were also studied using 45 microsatellite motifs. The maximum (86.67%) and minimum (28.89%) cross-species transferability were observed in A. caudatus and A. dubius, respectively, that indicated high variability present across the Amaranthus spp. Total 97 alleles were detected among 10 species of Amaranthus. The averages of major allele frequency, gene diversity, heterozygosity and PIC were 0.733, 0.347, 0.06, and 0.291, respectively. Nei's genetic dissimilarity coefficients ranged from 0.0625 (between A. tricolor and A. hybridus) to 0.7918 (between A. viridis and A. lividus). The phylogenetic tree grouped ten species into three major clusters. Genome-wide development of microsatellite markers and their transferability revealed relationships among amaranth species which ultimately can be useful for species identification, DNA fingerprinting, and QTLs/gene(s) identification. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-02930-5.

8.
Nature ; 431(7012): 1084-7, 2004 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-15510145

RESUMEN

Direct observations of sunspot numbers are available for the past four centuries, but longer time series are required, for example, for the identification of a possible solar influence on climate and for testing models of the solar dynamo. Here we report a reconstruction of the sunspot number covering the past 11,400 years, based on dendrochronologically dated radiocarbon concentrations. We combine physics-based models for each of the processes connecting the radiocarbon concentration with sunspot number. According to our reconstruction, the level of solar activity during the past 70 years is exceptional, and the previous period of equally high activity occurred more than 8,000 years ago. We find that during the past 11,400 years the Sun spent only of the order of 10% of the time at a similarly high level of magnetic activity and almost all of the earlier high-activity periods were shorter than the present episode. Although the rarity of the current episode of high average sunspot numbers may indicate that the Sun has contributed to the unusual climate change during the twentieth century, we point out that solar variability is unlikely to have been the dominant cause of the strong warming during the past three decades.


Asunto(s)
Actividad Solar , Atmósfera/química , Radioisótopos de Carbono/análisis , Efecto Invernadero , Hielo , Magnetismo , Luz Solar , Factores de Tiempo , Árboles/química , Árboles/crecimiento & desarrollo
9.
Nature ; 425(6959): 692-5, 2003 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-14562096

RESUMEN

Flares and X-ray jets on the Sun arise in active regions where magnetic flux emerges from the solar interior amd interacts with the ambient magnetic field. The interactions are believed to occur in electric current sheets separating regions of opposite magnetic polarity. The current sheets located in the corona or upper chromosphere have long been thought to act as an important source of coronal heating, requiring their location in the corona or upper chromosphere. The dynamics and energetics of these sheets are governed by a complex magnetic field structure that, until now, has been difficult to measure. Here we report the determination of the full magnetic vector in an interaction region near the base of the solar corona. The observations reveal two magnetic features that characterize young active regions on the Sun: a set of rising magnetic loops and a tangential discontinuity of the magnetic field direction, the latter being the observational signature of an electric current sheet. This provides strong support for coronal heating models based on the dissipation of magnetic energy at current sheets.

10.
Science ; 263(5143): 64-6, 1994 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-17748350

RESUMEN

Solar carbon monoxide spectra indicate the existence of a cool (less than 4000 kelvin) component to the solar chromosphere coexisting with the hot, bright gas at 6000 to 7000 kelvin. However, both the existence and the location of the cool component have been controversial. New high-resolution spectra show that carbon monoxide goes into emission just beyond the limb, allowing it to be probed without photospheric contamination. The cool component has temperatures as low as 3000 to 3500 kelvin and appears to cover 50 to 85 percent of the quiet solar surface. There is a steep temperature rise to normal chromospheric temperatures at a height of 900 to 1100 kilometers. Large horizontal velocities are seen, suggesting that the cool component is maintained by the supersonic adiabatic expansion of upwelling gas in overshooting granules.

12.
Saudi J Anaesth ; 10(3): 347-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27375396

RESUMEN

Osteoid osteoma (OO) is a benign bone tumor, with a male-female ratio of approximately 2:1 and mainly affecting long bones. Ten percent of the lesions occur in the spine, mostly within the posterior elements. Treatment options for OO include surgical excision and percutaneous imaging-guided radiofrequency ablation (RFA). Lesions within the spine have an inherent risk of thermal damage to the vital structure because of proximity to the neural elements. We report a novel use of the epidural catheter for air injection for the neuroprotection of nerves close to the OO of the spine. A 12-year-old and 30 kg male child with an OO of the L3 vertebra was taken up for RFA. His preoperative examinations were within normal limits. The OO was very close to the L3 nerve root. Under general anesthesia, lumbar epidural catheter was placed in the L3-L4 space under imaging guidance. Ten ml of aliquots of air was injected under imaging guidance to avoid injury to the neural structures due to RFA. The air created a gap between neural elements and the tumor and served as an insulating material thereby protecting the neural elements from damage due to the RFA. Postoperatively, the patient did not develop any neurological deficit.

13.
Sci Rep ; 6: 20235, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26819064

RESUMEN

Here we present the first direct comparison of cosmogenic (10)Be and chemical species in the period of 38-45.5 kyr BP spanning the Laschamp geomagnetic excursion from the EPICA-Dome C ice core. A principal component analysis (PCA) allowed to group different components as a function of the main sources, transport and deposition processes affecting the atmospheric aerosol at Dome C. Moreover, a wavelet analysis highlighted the high coherence and in-phase relationship between (10)Be and nitrate at this time. The evident preferential association of (10)Be with nitrate rather than with other chemical species was ascribed to the presence of a distinct source, here labelled as "cosmogenic". Both the PCA and wavelet analyses ruled out a significant role of calcium in driving the (10)Be and nitrate relationship, which is particularly relevant for a plateau site such as Dome C, especially in the glacial period during which the Laschamp excursion took place. The evidence that the nitrate record from the EDC ice core is able to capture the Laschamp event hints toward the possibility of using this marker for studying galactic cosmic ray flux variations and thus also major geomagnetic field excursions at pluri-centennial-millennial time scales, thus opening up new perspectives in paleoclimatic studies.

14.
Contraception ; 46(6): 527-36, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1283567

RESUMEN

The in vitro spermicidal activity of the commonly used surfactant spermicides and the antiseptic chlorhexidine, were quantified in a statistically reproducible manner, using donor semen and image capture analysis. The spermicidal activity was expressed as the ED50 under defined assay conditions. Using these parameters, the order of spermicidal activity was: Menfegol > nonoxynol-9 approximately benzalkonium chloride > sodium docusate > chlorhexidine. These differences were statistically significant.


PIP: Results with a new quantitative, reproducible, comparative method for assessing sperm immobilizing activity of spermicides are provided. The Hamilton Thorn Motility Analyzer is a computer-assisted system using image capture analysis and phase contrast optics. The compounds studied were nonoxynol-9 (nonylphenoxypolyethoxyethanol, Triton N101, Sigma, UK), benzalkonium chloride (Sigma, UK), dioctylsodium sulphosuccinate (sodium docusate, Cyanamid, UK), Menfegol (p-menthanylphenyl polyoxyethylene, Eisai Pharma-Chem Europe Ltd) and chlorhexidine gluconate (ICI, UK). Test materials were dissolved in Tyrode's solution containing glucose, except for chlorhexidine which was diluted in 290 mM sucrose. All tests were read at 1 minute. Results, expressed in ED50s were: nonoxynol, 0.134 mg/ml; sodium docusate, 0.308; Menfegol, 0.104; benzalkonium chloride, 0.135; and chlorhexidine, 1.032. When the percent motility was plotted against exposure time, the biguanide antiseptic chlorhexidine immobilized sperm much faster than did the detergent spermicides. This method is considered superior than previous standards, the Sander-Cramer test and the IPPF Approved test, because it allows comparison of relative spermicidal activity between different agents. Since local concentrations of intravaginal spermicides tend to be much higher than the ED50s found here, it is likely that other factors such as local distribution and dispersion of the spermicide are of more practical importance.


Asunto(s)
Espermicidas/farmacología , Espermatozoides/efectos de los fármacos , Tensoactivos/farmacología , Compuestos de Benzalconio/farmacología , Supervivencia Celular/efectos de los fármacos , Clorhexidina/análogos & derivados , Clorhexidina/farmacología , Ácido Dioctil Sulfosuccínico/farmacología , Humanos , Técnicas In Vitro , Masculino , Nonoxinol/farmacología , Polietilenglicoles/farmacología , Análisis de Regresión , Reproducibilidad de los Resultados , Motilidad Espermática/efectos de los fármacos , Factores de Tiempo
15.
Anaesth Intensive Care ; 41(1): 51-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23362890

RESUMEN

This randomised, double-blind study was designed to compare the duration of analgesia and adverse effects following intrathecal administration of dexmedetomidine or clonidine, both with bupivacaine, in trauma patients. Ninety adult trauma patients of American Society of Anesthesiologists physical status I-II, scheduled for lower limb surgery under subarachnoid block, were randomly allocated to one of three groups. All groups received hyperbaric bupivacaine 0.5% 3 ml, to which was added saline 0.5 ml (Group B): clonidine 50 µg (Group C) or dexmedetomidine 5 µg (Group D). The onset and duration of sensory and motor blockade, severity of postoperative pain, time to first rescue analgesia and total analgesic requirement for 24 hours were noted. There was no significant difference in the onset time of the block but the duration of sensory and motor blockade was prolonged in Groups C and D, compared with Group B. The time to analgesia was significantly prolonged in Group D (824±244 minutes) compared with Group C (678±178 minutes; P=0.01), the latter being longer than Group B (406±119 minutes; P=0.0001). Postoperative pain scores were lower in Groups C and D compared with group b. The requirement for rescue analgesia during the first 24 postoperative hours was significantly less in Groups C and D as compared to Group B (P=0.0001), but comparable between Groups C and D (P=0.203). In conclusion, dexmedetomidine 5 µg added to intrathecal bupivacaine 15 mg produces longer postoperative analgesia than clonidine 50 µg among trauma patients undergoing lower limb surgery.


Asunto(s)
Bupivacaína/farmacología , Clonidina/farmacología , Dexmedetomidina/farmacología , Dolor Postoperatorio/prevención & control , Adolescente , Adulto , Anciano , Analgésicos/administración & dosificación , Analgésicos/farmacología , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/farmacología , Anestésicos Locales/administración & dosificación , Anestésicos Locales/farmacología , Bupivacaína/administración & dosificación , Clonidina/administración & dosificación , Dexmedetomidina/administración & dosificación , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Inyecciones Espinales , Extremidad Inferior/lesiones , Extremidad Inferior/cirugía , Masculino , Persona de Mediana Edad , Bloqueo Nervioso/métodos , Índice de Severidad de la Enfermedad , Factores de Tiempo , Heridas y Lesiones/cirugía , Adulto Joven
16.
Iran J Parasitol ; 7(2): 61-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23109947

RESUMEN

BACKGROUND: The present study deals with the effect of helminthic infection as Nematode parasite like Aspiculuris tetraptera on the haematological parameters of infected and vaccinated mice. METHODS: Totally 15 mice were used. Five mice were used for positive control, 5 mice used for negative control and 5 mice used for experiment. The hematological parameters were studied viz. RBC, Hb, and serum protein values. RESULTS: The mice carrying heavy infection showed decrease in the Hb, RBC, and serum protein but in the vaccinated mice, all studied parameters were become on normal range. The level of immune response was assessed based on above studied hematological parameters in infected and vaccinated mice with Aspiculuris tetraptera. CONCLUSION: The increased value of RBC, Hb and Serum protein in infected and vaccinated mice compared to infected and non vaccinated suggested the involvement of blood parameters in immune response. This study also proves that somatic antigen of A. tetraptera was effective in imparting immunity in mice.

17.
J Pharm Bioallied Sci ; 4(Suppl 1): S74-6, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23066214

RESUMEN

Spray formulation can minimize pain and irritation experience during the application of conventional dosage forms. Econazole Nitrate is an active ingredient of the aerosol concentrate to be used for twice-daily application because of its long durability in the superficial layers of the fungal infected skin. The aim of this study is preliminary investigation of Econazole Nitrate spray by varying the concentrations of different constituents of the spray. The ratios of Propylene glycol (PG) and isopropyl myristate (IPM) were selected as independent variables in 2(2) full factorial designs, keeping the concentration of solvent, co-solvent and propellant LPG constant. Aerosol also contained Ethanol as solvent and Isopropyl alcohol as co-solvent. All ingredients of the aerosol were packaged in an aluminum container fitted with continuous-spray valves. Physical properties evaluated for the Econazole Nitrate spray included delivery rate, delivery amount, pressure, minimum fill, leakage, flammability, spray patterns, particle image and plume angle. Glass containers were used to study incompatibility between concentrate and propellant due to the ease of visible inspection. Isopropyl myristate at lower concentrate showed turbidity, while at high concentration it met the requirements for aerosol and produced Econazole Nitrate spray with expected characteristics.

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