The effects of Sceletium tortuosum in an in vivo model of psychological stress

Aim of the study

Sceletium, and especially Sceletium tortuosum, is traditionally used as masticator and thought to have a sedative effect which may be beneficial to reduce symptoms of anxiety and/or depression. The current study evaluated the scientific merit of these anecdotal claims in an in vivo model of psychological stress.

Materials and methods

Male Wistar rats were administered either placebo, 5 or 20 mg/kg/day of Sceletium tortuosum extract for 17 days by daily oral gavage. 50% of rats were exposed to repeated restraint stress lasting 1 h for the last 3 days of treatment. Rat behavioral changes in response to stress were assessed using the elevated plus maze on the last day of restraint, immediately after the restraint session. Rats were sacrificed 24 h after the last restraint exposure and whole blood collected.

Results

Behavior indicated a limited effect of lower dose Sceletium to decrease restraint stress-induced self-soothing behavior, as well as to decrease stress-induced corticosterone levels. However, increased IL-1β levels argue against the claim that the plant may act as selective serotonin reuptake inhibitor, while this result combined with increased levels of C-reactive protein and prostaglandin E₂ suggest intolerance to the treatment. Decreased IL-2 and increased IL-10 levels in response to Sceletium treatment suggest a suppressive effect on T helper 1 immune function.

Conclusions

Although data indicates a limited positive effect of Sceletium on restraint-induced anxiety, numerous side-effects were evident. More research is required to derive an optimal therapeutic dose.     

Influence of the degree of dentine mineralization on pulp chamber temperature increase during resin-based composite (RBC) light-activation

Objectives

To analyse the influence of the degree of dentine mineralization on the pulp chamber temperature increase during composite light-activation.

Methods

Dentine discs (2 mm thick) obtained from recently extracted teeth or those with extensive dentine sclerosis were analysed by FT-IR spectrometry in order to choose the two discs with the greatest difference in the degree of mineralization. A model tooth was set up with the dentine discs between a molar with the pulp chamber exposed and a crown with a standardized class II cavity. A K-type thermocouple was introduced into the molar root until it came into contact with the dentine discs and the cavity was filled with P60 resin composite. The temperature rise was measured for 120 s after light-activation began: Standard (S) 600 mW/cm²/40 s; Ramp (R) 0 → 800 mW/cm²/10 s + 800 mW/cm²/10 s; Boost (B) 850 mW/cm²/10 s and LED (L) 1.300 mW/cm²/40 s (n = 10). The same protocol was repeated after grinding the dentine discs to 1.0 and 0.5 mm thickness.

Results

The temperature increase was significantly higher in dentine with high degree of mineralization (p < 0.05). With respect to the dentine thickness, the following result was found: 2 mm < 1 mm < 0.5 mm (p < 0.05). The light-activation mode also presented significant difference as follows: S > R = L > B (p < 0.05).

Conclusions

The higher the degree of dentine mineralization the greater the increase in pulp chamber temperature. The temperature increase was influenced by the light-polymerization mode and dentine thickness.     

Multi‐Component Synthesis of Dihydropyrimidines by Iodine Catalyst at Ambient Temperature and in‐vitro Antimycobacterial Activity

An efficient and simple three‐component domino synthesis of some new dihydropyrimidines (DHPMs) from aromatic aldehydes, 1,3‐dicarbonyl compounds and N‐(3‐chloro‐4‐fluorophenyl)urea using molecular iodine as catalyst is described. The 1‐substituted dihydropyrimidines were isolated in good to excellent yields (78‐90%) within a short reaction time (4‐6 h) at ambient temperature. The biological evaluation revealed that the newly synthesized compounds ( 4a ‐ i and 5a ‐ i ) exhibited moderate antimycobacterial activity against Mycobacterium tuberculosis H₃₇ RV.     

患者自测腋温在临床运用的研究

目的：了解目前临床上患者自测腋温与护士按教科书规定的规范化测量腋温的测量结果是否有差异,讨论可否将自测腋温应用于临床。方法：对同一患者,在最接近的时问内先后采取让患者自测腋温与护士规范化测量腋温各-次,合计782例,采用统计描述及配对样本t检验的统计方法对结果进行处理。结果：临床患者自测腋温所测得的体温值与护士按教科书规定的规范化测量腋温所测得的体温值差异无统计学意义。结论：临床让患者自测体温的方法具有可行性、实用性。建议将体温测量作为临床护理健康教育内容之一,同时加强临床腋温操作的监督管理。     

Intravascular Temperature Control System to Maintain Normothermia in Organ Donors

Introduction  Temperature regulation in humans is controlled by the hypothalamus. After death by neurological criteria, the hypothalamus ceases to function and poikilothermia ensues. Preservation of normothermia in those patients destined to become organ donors is an important part of maintaining the normal physiology of the organs and organ systems. Typical means of achieving normothermia include increasing the temperature of the ambient air, infrared warming lights, instillation of warmed intravenous fluids, and warm air or water blankets. Methods  In this prospective case series of five organ donors, we used an intravascular temperature modulation catheter (Alsius, Irvine, CA) to maintain normothermia in organ donors declared dead by neurological criteria. Data on accuracy of temperature maintenance at 37°C and nursing ease of use were collected. Results  This intravascular temperature modulation catheter provided an accurate method of temperature regulation in brain death donor and easier to use from a nursing workload perspective. Conclusions  Intravascular warming is a viable method for the maintenance of normothermia in organ donors. The experience here provides some insight into the ability of these devices to warm patients in other clinical situations. Originally presented at the Neurocritical Care Society, 2nd Annual Meeting, San Diego, CA, 2004.     

Variance inflation in sequential calculations of body surface area, plasma volume, and prostate-specific antigen mass

OBJECTIVE

To assess the magnitude of variability among 11 formulae for human body surface area (BSA) and then among eight for plasma volume (PV), as used to represent physiological indices for body metabolism, drug dosages and body fluid management, and to evaluate the potential cumulative effect of variance inflation with prostate‐specific antigen (PSA) mass as an endpoint.

PATIENTS AND METHODS

In 3020 men undergoing robotic radical prostatectomy (RRP) at the Vattikuti Urology Institute between 2001 and 2008, the variation in BSA and PV formulae was calculated, as well as PSA mass, using analysis of variance (anova ), Bland‐Altman plots, linear regression, and correlation analyses.

RESULTS

For estimating BSA, anova indicated significant variance among the 11 formulae used (P < 0.001) with a between‐groups variance of 5.45. Bland‐Altman plots reported bias when the Dubois formula was compared to other BSA formulae. Furthermore the anova for PV, with BSA as a predictor, indicated significant variance among the eight formulae used (P < 0.001), with a mean between‐group variance of 444.4 and a mean inflation factor of 81.5. Scatter plots between one PV formula (Boer) and others had a good linear fit. For PSA mass, anova indicated significant variance (P < 0.001) using PV as a predictor, with a mean between‐group variance of 16 799.6 and a mean variance inflation factor of 37.8.

CONCLUSIONS

There is significant variation in the BSA calculated by commonly used formulae. This variation is carried over and further magnified in the sequential calculation of PV and PSA mass. Hence arbitrary selection of BSA and PV formulae is likely to affect inferences.     

Findings of preserved implicit attention in methamphetamine dependent subjects

Long-term methamphetamine (MA) abuse is associated with a wide range of deficits on explicit tasks of selective attention. Less is known however about the effects of MA abuse on implicit measures of attention. Accordingly, we used a computerized spatial priming task to assess implicit attentional processes in 54 MA dependent subjects (mean age=37.04+/-8.9 years) and 32 healthy controls without history of any form of substance abuse (mean age=33.63+/-7.05 years). The MA dependent subjects had been drug-abstinent a minimum of 3 weeks with a mean duration of MA use of 13.27+/-7.75 years. The MA dependent subjects did not differ significantly from controls on either inhibitory priming [p=.37] or facilitory priming) [p=.69]. This result comports with our earlier findings of intact object-based priming in MA dependent individuals and suggests that intact priming effects extend across spatial domains. Further, this pattern of sparing suggests that cortical brain systems typically supporting implicit attentional functioning are relatively intact in long-term MA dependent individuals whereas brain systems supporting explicit attentional processes are affected.