发形霞水母毒素分离产物溶血活性的比较及其影响因素分析

目的:分离发形霞水母刺丝囊毒素(nematocyst venom,NV)与无刺丝囊触手提取物(tentacle-only extract,TOE),比较二者的溶血活性,分析其影响因素.方法:采用自溶、离心方法分离发形霞水母NV和TOE,比较二者的溶血活性,观察提取物浓度、温度和pH值等因素对二者溶血活性的影响.结果:成功分离到NV与TOE;二者浓度相关溶血活性曲线均呈"S"形,溶血分数50%时所对应的质量浓度(HU50)分别为8μg/ml和67μg/ml,前者溶血活性强度约为后者的8.4倍;温度对二者溶血活性影响较大,最大溶血活性都出现在40℃;pH值对二者溶血活性也有影响,在pH 8处二者都具有最大的溶血活性,但后者较前者更为敏感.结论:发形霞水母毒素分离产物NV和TOE均具有溶血活性,且前者强于后者;二者溶血活性受浓度、温度和pH值的影响.     

The in vivo cardiovascular effects of an Australasian box jellyfish (Chiropsalmus sp.) venom in rats.

Using a new technique to extract venom from the nematocysts of jellyfish, the in vivo cardiovascular effects of Chiropsalmus sp. venom were investigated in anaesthetized rats. Chiropsalmus sp. venom (150 microg/kg, i.v.) produced a transient hypertensive response (44+/-4 mmHg; n=6) followed by hypotension and cardiovascular collapse. Concurrent artificial respiration or pretreatment with Chironex fleckeri antivenom (AV, 3000 U/kg, i.v.) did not have any effect on the venom-induced hypertensive response nor the subsequent cardiovascular collapse. The cardiovascular response of animals receiving venom after the infusion of MgSO4 (50-70 mM @ 0.25 ml/min, i.v.; n=5) alone, or in combination with AV (n=5), was not significantly different from rats receiving venom alone. Prior administration of prazosin (50 microg/kg, i.v.; n=4) or ketanserin (1 mg/kg, i.v.; n=4) did not significantly attenuate the hypertensive response nor prevent the cardiovascular collapse induced by venom (50 microg/kg, i.v.). In contrast to previous work examining C. fleckeri venom, administration of AV alone, or in combination with MgSO4, was not effective in preventing cardiovascular collapse following the administration of Chiropsalmus sp. venom. This indicates that the venom of the two related box jellyfish contain different lethal components and highlights the importance of species identification prior to initiating treatment regimes following jellyfish envenoming.     

Development of rear‐impeller axial flow blood pump for realization of axial flow blood pump installed at aortic valve position

In this study, rear‐impeller axial flow blood pumps (RIAFBP) were developed to realize a trans‐valve axial ventricular assist device (VAD) which consists of the latter blood pump and a polymer monomembrane aortic valve, such as the jellyfish valve. The motor of the RIAFBP is installed in the left ventricle, and its impeller is placed at the aortic valve position. In the prototype RIAFBP, the rotation of the motor is sustained by polyethylene bushings. The RIAFBP has a length of 50 mm and diameter of 19.6 mm. The miniature RIAFBP has the same construction as that of the prototype; however, it employs a ceramic bearing and fin bearing to improve endurance and to reduce blood stagnation. The miniature RIAFBP has a length of 63 mm and diameter of 12 mm. Both RIAFBPs were examined by an in vitro experiment using a 33% glycerin solution. The prototype RIAFBP achieved a maximum pump outflow of 8.5 L/min against a pump head of 100 mm Hg at a rotational speed of 12 000 rpm. The miniature RIAFBP achieved 7 L/min against a pump head of 70 mm Hg at a rotational speed of 21 600 rpm. In conclusion, the miniature RIAFBP has enough pump performance to realize the trans‐valve axial VAD.     

OPIOID THERAPY FOR TREATING RHEUMATOID ARTHRITIS PAIN

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online (http://www.thecochranelibrary.com). The January 2014 issue (1st DVD for 2014) contains 5840 complete reviews, 2342 protocols for reviews in production, and 28,000 short summaries of systematic reviews published in the general medical literature. In addition, there are citations of 763,000 randomized controlled trials, and 15,700 cited papers in the Cochrane Methodology Register. The Health Technology Assessment database contains some 13,000 citations. Ninety-four new reviews have been published in the previous 3 months, of which five have potential relevance for practitioners in pain and palliative medicine. The impact factor of the Cochrane Library stands at 5.715. Readers are encouraged to access the full report for any articles of interest, as only a brief commentary is provided.     

Jellyfish Envenomation Presenting with Delayed Identical Cutaneous Lesions in a Mother and Child

Jellyfish envenomation can present with local cutaneous lesions both immediate and delayed. While the immediate reaction is toxin mediated, an immune mechanism is responsible for the delayed eruptions. This is a report of a mother and child who developed identical papular lesions in a bizarre, linear distribution after coming in contact with jellyfish almost simultaneously while on holiday. Histology showed focal basal cell degeneration along with peri-vascular and peri-appendageal lympho-mononuclear infiltrate. Both patients responded well to topical tacrolimus.     

Preliminary Results of the in Vivo and in Vitro Characterization of a Tentacle Venom Fraction from the Jellyfish Aurelia aurita

The neurotoxic effects produced by a tentacle venom extract and a fraction were analyzed and correlated by in vivo and in vitro approaches. The tentacle venom extract exhibited a wide range of protein components (from 24 to >225 kDa) and produced tetanic reactions, flaccid paralysis, and death when injected into crabs. Two chromatography fractions also produced uncontrolled appendix movements and leg stretching. Further electrophysiological characterization demonstrated that one of these fractions potently inhibited ACh-elicited currents mediated by both vertebrate fetal and adult muscle nicotinic acetylcholine receptors (nAChR) subtypes. Receptor inhibition was concentration-dependent and completely reversible. The calculated IC₅₀ values were 1.77 μg/μL for fetal and 2.28 μg/μL for adult muscle nAChRs. The bioactive fraction was composed of a major protein component at ~90 kDa and lacked phospholipase A activity. This work represents the first insight into the interaction of jellyfish venom components and muscle nicotinic receptors.     

Epidemiology of jellyfish stings reported to summer health centres in the Salento peninsula (Italy)

Background:  The presence of jellyfish along coasts constitutes a potentially serious public health problem because of the toxic effects of contact with them.
Objective:  To determine the epidemiology of jellyfish stings in the Province of Lecce, Italy, in 2007.
Methods:  The study involved the gathering and processing of data on patients seeking medical treatment at summer first aid centres and hospitals along the coast of Salento following contact with jellyfish.
Results:  In 2007, 446 bathers sought medical assistance following contact with jellyfish. The spatial distribution indicates a greater frequency of stings sustained along the Adriatic coast, while the time analysis shows patterns related to wind direction. Most of the injuries were seen in persons aged between 1 and 10 years and in females. In 24% of cases, injuries were sustained to several parts of the body, while single injuries were mainly to the lower limbs (33%). In 4.9% of cases, there were complications, including one case of anaphylactic shock.
Conclusion:  In the light of the significant level of medical assistance provided, there is a need to identify suitable strategies that will guarantee the best response in terms of both prevention and treatment.     

Partial purification of cytolytic venom proteins from the box jellyfish, Chironex fleckeri

Venom proteins from the nematocysts of Chironex fleckeri were fractionated by size-exclusion and cation-exchange chromatography. Using sheep erythrocyte haemolysis as an indicator of cytolytic activity, two major cytolysins, with native molecular masses of approximately 370 and 145kDa, and one minor cytolysin ( approximately 70kDa) were isolated. SDS-PAGE and western blot protein profiles revealed that the 370kDa haemolysin is composed of CfTX-1 and CfTX-2 subunits ( approximately 43 and 45kDa, respectively); the most abundant proteins found in C. fleckeri nematocyst extracts. The 145kDa haemolysin predominately contains two other major proteins ( approximately 39 and 41kDa), which are not antigenic towards commercially available box jellyfish antivenom or rabbit polyclonal antibodies raised against whole C. fleckeri nematocyst extracts or CfTX-1 and -2. The kinetics of CfTX-1 and -2 haemolytic activities are temperature dependent and characterised by a pre-lytic lag phase ( approximately 6-7min) prior to initiation of haemolysis. Significant amino acid sequence homology between the CfTX proteins and other box jellyfish toxins suggest that CfTX-1 and -2 may also be lethal and dermonecrotic. Therefore, further in vivo and in vitro studies are required to investigate the potential roles of CfTX-1 and -2 in the lethal effects of C. fleckeri venom.