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1.
J Nat Med ; 77(3): 614-619, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36939955

RESUMO

In the Yarlung Zangbo River Valley of the southeastern Tibetan Plateau, China (29°07'49.5"N, 92°41'11.0"E, 3256 m above sea level), we found an Ephedra saxatilis community in the xeric steppe with shrubland vegetation habitat of the broad alluvial plain of the river with soil having relatively higher water-soluble cation (Ca2+, 8.62; K+, 1.94; Mg2+, 2.38 mmol/100 g dry soil weight) and nitrogen (NO3-, 21.78; NH4+, 1.82 mmol/100 g dry soil weight) content. The ranges of ephedrine and pseudoephedrine in 13 E. saxatilis samples were as follows: ephedrine, not detected-3.03 of dry weight (%DW) and pseudoephedrine, not detected-1.36%DW. The 13 E. saxatilis plants collected in the study area showed intraspecific variability of ephedrine and pseudoephedrine with 6 samples containing ephedrine and pseudoephedrine, 6 samples containing only ephedrine, and 1 sample containing only pseudoephedrine.


Assuntos
Ephedra , Efedrina , Pseudoefedrina , Rios , Tibet , Solo , China
2.
Front Psychiatry ; 13: 918417, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774091

RESUMO

Background: COVID-19-related anxiety, sleep problems, and loneliness may be risk factors for school refusal in children and adolescents. However, few studies have examined the mechanisms by which these risk factors cause school refusal. This study examined the process by which COVID-19-related anxiety, sleep problems, and loneliness cause school refusal, using structural equation modeling. Methods: In this cross-sectional questionnaire-based study, 256 (109 male, 147 female, mean age: 15.37 ± 0.48 years) senior high school students were asked to complete the Stress and Anxiety associated with Viral Epidemics-6 questionnaire to assess COVID-19-related anxiety, the Athens Insomnia Scale (AIS), Sleep Debt Index (SDI), and chronotype (MSFsc) to assess sleep problems, the Three-Item Loneliness Scale (TILS) to assess loneliness, and Feelings of School-Avoidance Scale (FSAS) to assess school refusal. Results: Structural equation modeling showed that sleep problems affected loneliness (ß = 0.52) and feelings of school refusal (ß = 0.37), and that loneliness affected feelings of school refusal (ß = 0.47). There was no significant pathway of COVID-19-related anxiety on sleep problems, loneliness, or feelings of school refusal. The indirect effect of sleep problems on feelings of school refusal through loneliness was significant. The results of hierarchical multiple regression analysis showed that AIS (ß = 0.30) and SDI (ß = 0.13) scores were associated with TILS, and AIS (ß = 0.26) and MSFsc (ß = -0.14) scores were associated with FSAS scores. Conclusion: The findings of this study showed that sleep problems affected feelings of school refusal via both direct and indirect pathways through the exacerbation of loneliness. To prevent school refusal in adolescents, addressing the indirect pathway via loneliness could be effective in improving insomnia and sleep debt, while addressing the direct pathway could be effective in improving insomnia and chronotype.

3.
J Nat Med ; 76(3): 703-714, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35461469

RESUMO

In the Kaluxung River catchment of the southeastern Tibetan Plateau in China, we identified three Ephedra gerardiana communities on different soils and glacial landforms from 4842 to 4899 m above sea level: a moraine community located on constantly collapsing sandy gravel alpine steppe slopes with exposed bedrock on the outer slope of the terminal moraine of the Qiangyong Glacier on Mt. Kaluxung; an outwash plain community located on a gentle alpine steppe slope with exposed bedrock at the terminal end of the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang; and a river terrace community located in an alpine meadow on a rock-scattered flat river terrace along a glacier-fed river in the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang. Based on the finding of identical DNA sequences of the intergenic spacers of chloroplast trnT-trnF and trnS-trnfM regions for all Ephedra specimens examined in this study, the E. gerardiana in this study were considered to comprise a genetically homogeneous population. Analysis of the relationship between ephedrine alkaloid profiles of these three communities and soil characteristics showed that the river terrace community in wet alpine meadow had significantly lower ephedrine content than did the moraine and outwash plain communities in dry alpine steppe (moraine community, 1.52 ± 0.44; outwash plain community, 1.42 ± 0.68; river terrace community, 0.33 ± 0.65%DW), but pseudoephedrine content showed the reverse pattern (moraine community, 0.86 ± 0.30; outwash plain community, 0.73 ± 0.60; river terrace community, 1.50 ± 0.71%DW). In addition, total alkaloid (ephedrine and pseudoephedrine) content in the river terrace community (1.83 ± 0.24%DW) was significantly lower than that in the moraine community (2.38 ± 0.64%DW) and outwash plain community (2.15 ± 0.55%DW).


Assuntos
Alcaloides , Ephedra , China , Ephedra/genética , Efedrina , Pseudoefedrina , Solo , Tibet
4.
J Nat Med ; 75(1): 246-258, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33090362

RESUMO

In Uzbekistan, Ephedra distachya L., E. equisetina Bunge, E. foliata Boiss. ex C. A. Mey., E. lomatolepis Schrenk, and E. strobilacea Bunge show species specificity for habitat environments and physical and chemical characteristics of habitat soils. Furthermore, the relationship between soil characteristics and ephedrine and pseudoephedrine contents was examined. E. distachya was found growing from 80 to 200 m above sea level (a.s.l) in the Plateau Ustyurt on the desert steppe of cliffs on soil having relatively higher loss on ignition (19.8-33.8%) and water-soluble cations (Ca2+, 5.14-133.13; Mg2+, 0.85-3.18; and Na+, 2.27-8.33 mmol/100 g dry soil weight) than for other Ephedra habitats. E. strobilacea was found growing on the flat sandy Kyzylkum desert at 94 m a.s.l. and had habitat soil that was the driest with the lowest loss on ignition (2.9%) and highest Na+ (9.05 mmol/100 g dry soil weight) of all the Ephedra habitat soils. On dry steppe from 1054 to 1819 m a.s.l., E. foliata, E. lomatolepis, and E. equisetina formed not only a single community but also a complex community on constantly collapsing sandy gravel slope with relatively higher Ca2+ (3.40-17.44 mmol/100 g dry soil weight) soil content. Notably, E. equisetina grew on the dry steppe of constantly collapsing sandy gravel slopes, in rocky areas, on sandy gravel floodplains of rivers, and on stable humus soil at the base of coniferous trees in a wide range of habitats from dry steppe to coniferous forest zones at altitudes ranging from 1392 to 1819 m a.s.l., as reflected in the greater variability than for other Ephedra habitats in the parameters of loss on ignition (1.4-34.8%), pH (7.1-9.6), NO3- (0.08-35.17 mmol/100 g dry soil weight), Ca2+ (0.24-17.44 mmol/100 g dry soil weight), Mg2+ (not detected-1.25 mmol/100 g dry soil weight), and Na+ (0.13-5.19 mmol/100 g dry soil weight). Ephedrine alkaloids were not detectable in E. strobilacea, E. foliata, and E. lomatolepis. Almost all E. distachya contained only pseudoephedrine (1.25-1.59% of dry weight, %DW), while E. equisetina contained from 1.31 to 2.05%DW ephedrine and from 1.29 to 2.80%DW pseudoephedrine. Ephedrine and pseudoephedrine in E. equisetina showed a statistically significant negative correlation with soil Cl- and Mg2+, respectively.


Assuntos
Alcaloides/química , Ephedra/química , Ecossistema , Solo , Uzbequistão
5.
J Nat Med ; 74(4): 825-833, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32385566

RESUMO

In the Kali Gandaki Valley in Central Nepal, Ephedra gerardiana and E. pachyclada show species specificity for physical and chemical characteristics of soils. Here, the relationship between soil characteristics and ephedrine and pseudoephedrine contents was examined. E. gerardiana grew in moist alpine scrub and upper alpine meadow from 3735 to 4156 m a.s.l., while E. pachyclada grew in the lower Caragana steppe and dry alpine scrub from 2629 to 3671 m a.s.l. The soil texture of E. gerardiana and E. pachyclada collection sites were classified as loam or sandy loam mainly composed of sand and silt. Loss on ignition (%) of soil in E. gerardiana habitats (28.4-35.0%) was markedly higher than for that in E. pachyclada habitats (14.2-17.2%). E. pachyclada soil (pH 8.4-9.2) was more alkaline than that for E. gerardiana (pH 8.5). The five ions (Cl-, SO42-, Ca2+, Mg2+, and Na+) in soil of E. pachyclada (Cl-, 0.01-18.97 mmol/100 g dry soil weight; SO42-, 1.95-83.33; Ca2+, 3.79-77.91; Mg2+, 1.28-27.9; Na+, 0.94-34.49) were markedly higher than those of E. gerardiana (Cl-, 0.18-0.29; SO42-, 0.07-0.08; Ca2+, 4.19-4.59; Mg2+, 0.22-0.58; Na+, 0.93-1.40). The main factor contributing to strongly alkali soils for each species was different between E. gerardiana and E. pachyclada: CaCO3 for E. gerardiana and CaSO4, MgSO4, NaCl, or a combination of these for E. pachyclada. The total ephedrine and pseudoephedrine content in E. gerardiana and E. pachyclada ranged from 1.67-1.88%DW and 1.95-4.80%DW, respectively. Both E. gerardiana and E. pachyclada were amenable for use a raw material source for extraction of ephedrine and pseudoephedrine, and the ephedrine content of both species showed a statistically significantly positive correlation with Mg2+ and Na+ contents of the soil.


Assuntos
Ephedra/química , Solo/química , Nepal
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