A comparison of the bronchodilator action of pseudoephedrine and ephedrine in patients with reversible airway obstruction

Ecological and pharmacognostical characteristics in Ephedra saxatilis in the Yarlung Zangbo River Valley of southeastern Tibetan Plateau, China

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.

Evaluation of rooting characteristics of Ephedra cuttings by anatomy and promising strain selection based on rooting characteristics and alkaloid content

The differences in rooting characteristics of cuttings prepared from E. sinica strains were investigated and found that cuttings prepared from strains with high rooting characteristics showed approximately 90% of the cuttings were rooted, whereas cuttings prepared from low rooting characteristics did not root. To understand the reason for this substantial difference, the anatomy of nodes was examined and found that adventitious roots were generated from the cortex and parenchyma in pith. Calculations of the correlation coefficients between the rooting rate and the value of anatomy indicated that the rooting rate was positively correlated with the parenchyma in pith in the node. On the basis of the positive correlation, it is possible to estimate the rooting characteristics of new strains without having to prepare cuttings. Next, we conducted a screening for E. sinica strains on the basis of total alkaloids content [ephedrine (E) + pseudoephedrine (PE)] and selected strains having no less than 0.7% total alkaloids content as defined by the Japanese Pharmacopoeia 18th edition. Strains having characteristic E or PE content were uncovered: E-rich strains had 100% E content and PE-rich strains had 99% PE content. We were able to select E. sinica strains on the basis of two factors: high rooting rate of cuttings and high or characteristic alkaloid content. These strains are valuable for breeding.

Seasonal variation of alkaloids and polyphenol in Ephedra sinica cultivated in Japan and controlling factors

We investigated the seasonal variation of alkaloids (ephedrine and pseudoephedrine), total polyphenol, and sugar contents in Ephedra sinica cultivated in Japan and elucidated the controlling factors for the variation. In 2018, alkaloids and polyphenol contents increased dramatically from May to July, decreased to their lowest in October, and slightly increased again in November. The reduction of alkaloids and polyphenol contents in the autumn may be affected by precipitation in summer. In 2020, alkaloids and polyphenol contents started to decrease in late July when rainfall was abundant from July to August. In contrast, sucrose and starch contents continued to increase until September and remained high until October. Vascular bundles and fiber developed, and herbal stem weight increased from August to October. Alkaloids and total polyphenol contents tended to increase in November. At the same time, starch and sucrose contents decreased dramatically, whereas glucose and fructose contents increased. Sugar content decreased from October and was lowest in November. The seasonal variation of alkaloids and total polyphenol contents exhibited a contrasting tendency to the seasonal variation of sugar content and tissue development. The seasonal variation of alkaloids and total polyphenol contents was caused by the seasonal variation of sugar content and tissue development. In addition, it is suggested that anatomy may be used for alkaloids content estimation in Ephedra plants.

The Utility of Various Pre-anesthetic Medications Based on Type of General Anesthesia

Background:

Premedication is used prior to surgery to reduce the adverse effects that might result from general anesthesia.

Objective:

This study was performed to examine the types and utility of various pre-anesthetic agents in 100 patients aged between 3 and 60 years who were admitted to Baladrooz General Hospital for different surgical operations during February (winter) and April (spring) 2021.

Methods:

A total of 62 patients received isoflurane, and 7 patients received sevoflurane, both by inhalational administration. The other 31 subjects were administered Marcaine (bupivacaine) by spinal anesthesia.

Results:

In this study, eight types of pre-anesthetic medication were administered prior to anesthesia, as follows: hydrocortisone (35 patients), metoclopramide (25 patients), atropine (13 patients), dexamethasone (12 patients), midazolam (7 patients), morphine (3 patients), ephedrine (3 patients), and fentanyl (2 patients). The most commonly used pre-anesthetic agent administered with isoflurane was hydrocortisone (37 patients), while the least used were fentanyl and morphine, which were administered to 3 patients each. Hydrocortisone was the premedication most often used (6 patients) with isoflurane, followed by dexamethasone, midazolam, and metoclopramide (5, 2, and 2 patients, respectively). The preanesthetic agent used most often with sevoflurane was hydrocortisone (6 patients), followed by dexamethasone (5 patients) and metoclopramide and midazolam (2 patients each). The premedication most commonly used with bupivacaine was metoclopramide (25 patients), while the least used was midazolam (2 patients).

Conclusion:

The study showed that several different pre-anesthetic drugs were used prior to anesthetic agents, which suggests that the selection of a pre-anesthetic drug depends on the risks that might be incurred when using a specific anesthetic drug.

Research Progress on the Natural Product Aloperine and Its Derivatives

In this review, an effort towards the presentation of an all-around account of the recent progress on the natural product, aloperine is made, and the antivirus structure-activity relationship of its derivatives is also summarized comprehensively. In addition, the principal pharmacological effects and corresponding molecular mechanisms of aloperine are discussed. Some new modification directions of aloperine are given in the end, which might be brief guidance for further investigations on the natural product aloperine.

Environmental and soil characteristics in Ephedra habitats of Uzbekistan

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.

Influence of genetic factors on the ephedrine alkaloid composition ratio of Ephedra plants

We investigated the ephedrine alkaloid [(-)-ephedrine and (+)-pseudoephedrine] composition ratio of a crude Chinese herbal drug described in the Japanese Pharmacopoeia 'Ephedra herb (Chinese name: Mahuang)'. There were marked changes in the alkaloid composition ratio of wild plants in areas where both male and female clusters coexisted. However, in genetically homogeneous areas with the growth of male or female clusters alone, all of the coefficients of the regression lines were positive, but each gradient varied. This suggests that the alkaloid composition ratio has a clear tendency in each individual. Based on this, we cultivated individuals for vegetative propagation, and evaluated the alkaloid content ratio. Those propagated by separating the roots showed a specific tendency regardless of the cultivation area (Wakayama, Tanegashima). Those propagated by separating the herbaceous stem showed a specific tendency regardless of the soil or harvest time. In addition, we surveyed the (-)-ephedrine content ratio of 3- to 6-year-old strains. There was a high positive correlation coefficient between the previous and subsequent years. These findings suggest that the ephedrine alkaloid composition ratio of Ephedra herb depends on genetic factors, but not on environmental factors or the growth period.

Demographic, pathologic, and toxicological profiles of 127 decedents testing positive for ephedrine alkaloids

The relative toxicity of ephedra-containing dietary supplements is disputed. In order to ascertain the magnitude of the problem, we reviewed all autopsies in our Medical Examiner's jurisdiction, from 1994 to 2001, where ephedrine or any its isomers (E+) were detected. Toxicology testing results were tabulated and anatomic findings in E+ cases were compared to those in a control group of drug-free trauma victims. Of 127 E+ cases identified, 33 were due to trauma. Decedents were mostly male (80.3%) and mostly Caucasian (59%). Blood ephedrine concentrations were <0.49 mg/l in 50% of the cases, range 0.07-11.73 mg/l in trauma victims, and 0.02-12.35 mg/l in non-trauma cases. Norephedrine (NE) was present in the blood of 22.8% (mean of 1.81 mg/l, S.D.=3.14 mg/l) and in the urine of 36.2% (mean of 15.6 mg/l, S.D.=21.50mg/l). Pseudoephedrine (PE) was present in the blood of 6.3% (8/127). More than 88% (113/127) of the decedents also tested positive for other drugs, the most common being cocaine (or its metabolites) and morphine. The most frequent pathologic diagnoses were hepatic steatosis (27/127) and nephrosclerosis (22/127). Left ventricular hypertrophy was common, and coronary artery disease (CAD) detected in nearly one third of the cases. The most common findings in E+ deaths are those generally associated with chronic stimulant abuse, and abuse of other drugs was common in those with CAD. There were no cases of heat stroke or rhabdomyolysis. In most cases, norephedrine was not detected, suggesting it plays no role in ephedrine toxicity.

Nonprescription drugs and hypertension. Which ones affect blood pressure?

Hypertensive patients should be aware of the possible effects of nonprescription medications on blood pressure control. For absolute safety, no adrenergic agents should be used. Nasal phenylephrine hydrochloride is probably the safest of these agents, and pseudoephedrine hydrochloride may also be safe. Phenylpropanolamine hydrochloride and ephedrine sulfate are probably best avoided. The effects of other adrenergic agents (eg, epinephrine) on blood pressure have not been clinically evaluated. Ibuprofen may elevate blood pressure if taken in maximum over-the-counter doses for more than a few days. The ethanol and sodium chloride content of nonprescription drugs taken in recommended doses does not appear to pose a great hazard.

Drug interactions in hypertensive patients. Pharmacokinetic, pharmacodynamic and genetic considerations

Antihypertensive treatment has proven benefits, and the number of patients being treated with these drugs is significant. Hypertensive patients may have other medical illnesses for which they receive medications, and interactions between antihypertensive agents and other drugs is likely. Some of these interactions may lead to undesirable effects or even loss of blood pressure control. However, drug interactions can also be beneficial when 2 antihypertensive drugs with different pharmacological actions are prescribed in combination and with a clear therapeutic objective in mind. Clinicians should be aware of the mechanisms and the consequences of the different types of interaction in hypertensive patients, so that a desired pharmacological response can be achieved with the fewest side effects in the patients.

Pharmacokinetics of non-prescription sympathomimetic agents

The pharmacokinetics of non-prescription sympathomimetic agents are discussed with respect to absorption from the gastrointestinal tract, volumes of distribution, metabolism and renal excretion. Where specific data are not available, postulations are made with inference from the chemical structures of these agents, or from studies with other drugs. No studies on hypertensive patients have been found, but attempts are made to correlate any possible changes in the pharmacokinetics of these sympathomimetic agents to hypertensive patients as a high proportion of the elderly population is hypertensive. Sympathomimetic agents with lesser polar hydroxyl groups, for example, are thought to be more lipophilic and are more readily absorbed from the gastrointestinal tract, have higher volumes of distribution, and are more extensively metabolized. Major metabolic pathways include oxidation, deamination, demethylation, and conjugation. Most of these agents are excreted primarily through the kidneys and due to their basic nature, the rate of excretion is dependent on urinary pHs. Any alteration in kidney functions such as in the aged is, therefore, expected to have some clinical significance on the pharmacokinetics of these agents.

Non-prescription sympathomimetic agents and hypertension

In recent years, considerable attention has been focused on the pressor effects of nonprescription sympathomimetic agents. The impact and usage of these agents especially ephedrine, pseudoephedrine, phenylpropanolamine and phenylephrine, in hypertensive patients has been the topic of constant debates. The present review is an attempt to report and evaluate all the clinical trials and cases of pressor reactions associated with these 4 agents. The study protocols used in these clinical trials are examined and comments made on any diversion from the standard design. Many factors are found to cause the discrepancies in the data available. It is concluded that ephedrine and phenylpropanolamine are best avoided by hypertensive patients due to higher probability of causing pressor reactions. Data on pseudoephedrine and phenylephrine appear to indicate non-significant effects on blood pressure of normotensive subjects when used at the recommended oral dose as nasal decongestants. Phenylephrine is also commonly employed in nasal and eye drops and the limited data available appear to support its usage in hypertensive patients. However, it is noted that most of the clinical trials involve normotensive subjects and the majority of the results could not be verified due to inadequacies in the study design. This paucity and inconclusive information on hypertensive patients warrants further investigations with emphasis on the study protocols used.