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Plant cell cultures are a valuable resource for the exploration, isolation, and production of metabolites of pharmaceutical interest. Antimicrobial activity against Escherichia coli, Salmonella typhimurium, Bacillus cereus, and Streptococcus aureus, of ethanolic extracts of cell suspension culture of Thevetia peruviana, has been previously demonstrated and associated with the flavonoids content such as dihydroquercetin (DHQ). This study evaluated the influence of three extraction methods on antioxidant activity (AA) and DHQ content in ethanolic extracts of T. peruviana cells grown in a bioreactor and harvested in the stationary phase. The extractions were developed by shaking, bath ultrasound, and probe ultrasound (PUS) with 20, 50, and 80% v/v ethanol. DHQ concentration was determined by high-performance liquid chromatography and AA by 2,2-diphenyl-1-picrylhydrazyl colorimetric assay. PUS (frequency 50 MHz, power 20% and 80% ethanol) significantly improved (p-value < 0.05) the extraction of flavonoids = 127.51±4.09 mg quercetin-equivalents/gram dry weight (g.d.w); DHQ = 512.07 μg/g.d.w and AA = 44.50±3.67 mg Trolox-equivalents/g.d.w. The development of a method that maximizes the biotechnological production of DHQ, is highlighted. This compound is a potential agent against S. aureus methicillin-resistant. [ABSTRACT FROM AUTHOR]

Thevetia peruviana is a tropical plant with antioxidant and antimicrobial properties attributed to flavanone and flavonol glycosides that are characteristic of this species. The influence of the exogenous addition of the phytohormones methyl jasmonate-MJ and salicylic acid-SA on the production of phenolic compounds (PC) in suspension cell cultures of T. peruviana was evaluated. Shake-flask scale cultures were elicited with MJ (3 μM), SA (300 μM), and MJ/SA (3 μM/300 μM); cells were harvested every 24 hours postelicitation for 6 days. Profile of PC was determined in ethanolic extracts by high performance liquid chromatography coupled to diode array detector (HPLC-DAD) and proton nuclear magnetic resonance spectroscopy (1H-NMR). MJ significantly increased the hydroxycinnamates production such as ferulic acid (FA) and polyphenols such as chlorogenic acid (CGA), and decreased flavonols production such as dihydroquercetin (DHQ). Salicylic acid increased the benzoic acid derivatives (BA) production. In contrast, simultaneous treatment with MJ/AS inhibited the CQA and FA production, while increased the DHQ biosynthesis. In conclusion, simultaneous treatment with MJ and SA results in an antagonistic effect on the production of flavonoids from T. peruviana. It is possible that salicylates suppress some aspects of the jasmonate signaling [ABSTRACT FROM AUTHOR]

Abstract: Spain is frequently the entrance country into the European Union for undocumented immigrants, especially those from the Magreb (Northern Africa). Forensic age estimates for these persons are difficult because systematic studies of dental maturity are lacking. Three different populations were analyzed to determine the pattern of development of third molars as a tool for age estimation in people of different ethnic and geographic origin. Orthopantomograms from two different populations of Spanish origin (Galicia in northwestern continental Spain, and Ceuta, a Spanish province in Northern Africa) were compared to radiographs of molars from a Magrebian population (Northern Africa) resident in Ceuta. Orthopantomograms were obtained from a private dental clinic (n =344) in Galicia and from the Public Oral Health Services (n =228) in Ceuta. We looked for differences in third molar mineralization (determined with the Demirjian scale) that might serve as age indicators (older versus younger than 18 years). Differences in maturation patterns were found between sexes and populations of origin. Mineralization of tooth 38 was more advanced in males than females among subjects 18 years of age and older in all three populations. Moreover, mineralization of tooth 38 in subjects aged 18 years and older was significantly slower in the Spanish-Galicia population than in the Magrebian-Ceuta population. We found no significant differences between Magrebian and Spanish individuals from Ceuta. We conclude that differences in tooth 38 mineralization may be related more with socio-geographical than ethnic origin (ancestry), and thus constitute evidence of the relevance of socio-geographic rather than genetic factors in third molar development. We used ROC analysis to determine the accuracy of the examiner''s ability to correctly estimate age as younger or older than 18 years. The results suggest that Demirjian stage for tooth 38 can be considered a good indicator of age in all three populations. [Copyright &y& Elsevier]

This paper presents an energetically autonomous IoT sensor powered via thermoelectric harvesting. The operation of thermal harvesting is based on maintaining a temperature gradient of at least 26.31 K between the thermoelectric-generator sides. While the hot side employs a metal plate, the cold side is attached with a phase-change material acting as an effective passive dissipative material. The desired temperature gradient allows claiming power conversion efficiencies of about 26.43%, without efficiency reductions associated with heating and soiling. This work presents the characterization of a low-cost off-the-shelf thermoelectric generator that allows estimating the production of at least 407.3 mW corresponding to 2.44 Wh of available energy considering specific operation hours—determined statistically for a given geographic location. Then, the energy production is experimentally verified with the construction of an outdoor IoT sensor powered by a passively-cooled thermoelectric generator. The prototype contains a low-power microcontroller, environmental sensors, and a low-power radio to report selected environmental variables to a central node. This work shows that the proposed supply mechanism provides sufficient energy for continuous operation even during times with no solar resource through an on-board Li-Po battery. Such a battery can be recharged once the solar radiation is available without compromising sensor operation. [ABSTRACT FROM AUTHOR]

The objective of the present article is to establish the relationship between the thoracic vertebrae with the structures and organs located within the thoracic cavity. Throughout the review of various medical textbooks data was gathered, consequently inspecting and crossing this information using the cadaveric samples available at Universidad Militar Nueva Granada amphitheater. Thus, providing practical and academical data about the anatomical relation between thoracic vertebral bodies with the rib cage and its corresponding contents. [ABSTRACT FROM AUTHOR]