The healthcare volunteer

Every year, volunteers contribute billions of dollars worth of time to the healthcare industry. Despite their contributions, however, little is known about who these volunteers are, what they do, why they volunteer, as well as the costs and benefits they bring to institutions. This article examines these and other characteristics of the healthcare volunteer.     

致病性鳞翅目刺蛾幼虫致皮炎及防制研究

目的探讨致病性鳞翅目刺蛾幼虫形态及所致皮炎患者临床症状，为采取早期控制措施提供科学依据。方法用老熟茶毛虫、桑毛虫触刺豚鼠的腹面皮肤和自愿者上肢或自然染毒，动态观察茶毛虫皮炎的病程，对豚鼠皮炎病灶作常规病理学观察，比较豚鼠、自愿者染毒前、后血象变化。结果自愿者皮肤被幼虫触刺后，表现为红、肿、痛、热，烧灼、麻木感，继而呈现丘疹、斑丘疹、斑块、风团块，部分病例出现周身不适76．64％，烦燥32．71％，腋下淋巴结肿大16．82％。豚鼠皮疹病理切片见表皮水疱、脓疱改变。染毒后白细胞、嗜酸性粒细胞高于染毒前。结论鳞翅目刺蛾幼虫具有致病性，致病机制为机械刺伤、生物毒性和变态反应。     

The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas

The controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a) a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b) an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c) application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter.     

The prebiotic effects of biscuits containing partially hydrolysed guar gum and fructo-oligosaccharides--a human volunteer study

Prebiotics are non-digestible food ingredients that target selected groups of the human colonic microflora, thus having the ability to alter the composition towards a more 'beneficial' community, i.e. selectively increasing populations of bifidobacteria and/or lactobacilli. In the present study the prebiotic potential of partially hydrolysed guar gum (PHGG) and fructo-oligosaccharides (FOS) in a biscuit was assessed in human volunteers. Fluorescent in situ hybridization using oligonucleotide probes targeting Bacteroides spp., Bifidobacterium spp., Clostridium spp. and Lactobacillus-Enterococcus spp. were used for the bacteriology and total bacteria were enumerated using the fluorescent stain 4',6-diamidino-2-phenylindole. Thirty-one volunteers consumed daily either three experimental biscuits (providing a total (g/d) of 6.6 FOS and 3.4 PHGG) or three placebo biscuits for two 21-d crossover periods. Bifidobacteria significantly increased in number on ingestion of the experimental biscuits compared with pre-treatment and placebo population levels. Bifidobacterial numbers returned to pretreatment levels within 7 d of the cessation of intake of experimental biscuits. A correlation was observed between the initial faecal bifidobacterial numbers and the magnitude of bifidogenesis, with volunteers who possessed low initial population levels of bifidobacteria experiencing the greatest increase in bifidogenesis. No changes were observed in the other bacterial groups monitored during the trial. Thus, the prebiotic nature of FOS and PHGG was maintained in a final food product as evidenced from the selective increase in bifidobacterial numbers.     

Oral and dermal absorption of chlorpyrifos: a human volunteer study

OBJECTIVES: To determine the kinetics of elimination of urinary dialkylphosphate metabolites after oral and dermally applied doses of the organophosphate pesticide chlorpyrifos to human volunteers and to determine whether these doses affected plasma and erythrocyte cholinesterase activity. METHOD: Five volunteers ingested 1 mg (2852 nmol) of chlorpyrifos. Blood samples were taken over 24 hours and total void volumes of urine were collected over 100 hours. Four weeks later 28.59 mg (81567 nmol) of chlorpyrifos was administered dermally to each volunteer for 8 hours. Unabsorbed chlorpyrifos was washed from the skin and retained for subsequent measurement. The same blood and urine sampling regime was followed as for the oral administration. Plasma and erythrocyte cholinesterase concentrations were determined for each blood sample. The concentration of two urinary metabolites of chlorpyrifos--diethylphosphate and diethyl-thiophosphate--was determined for each urine sample. RESULTS: The apparent elimination half life of urinary dialkylphosphates after the oral dose was 15.5 hours and after the dermal dose it was 30 hours. Most of the oral dose (mean (range) 93% (55-115%)) and 1% of the applied dermal dose was recovered as urinary metabolites. About half (53%) of the dermal dose was recovered from the skin surface. The absorption rate through the skin, as measured by urinary metabolites was 456 ng/cm2/h. Blood plasma and erythrocyte cholinesterase activity did not fall significantly during either dosing regime. CONCLUSION: An oral dose of chlorpyrifos was readily absorbed through the skin and almost all of the dose was recovered as urinary dialkylphosphate metabolites. Excretion was delayed compared with the oral dose. Only a small proportion of the applied dose was recovered during the course of the experiment. The best time to collect urine samples for biological monitoring after dermal exposure is before the shift the next day. The amounts of chlorpyrifos used did not depress acetyl cholinesterase activity but could be readily detected as urinary dialkylphosphate metabolites indicating that the urinary assay is a more sensitive indicator of exposure.

 

     

人巨细胞病毒糖蛋白及其亚型的致病性

人巨细胞病毒(HCMV)是人类感染率很高的一种病毒,其包膜糖蛋白在病毒的致病性方面起着很重要的作用。包膜糖蛋白由于其多态性,可以划分出很多亚型。虽然大量的研究工作致力于HCMV糖蛋白不同亚型的致病性方面,但由于该病毒庞大的基因组,宿主与病毒相互作用的变化,病毒株地理分布的不同,病毒亚型混合感染等因素,该方面研究尚无突破性进展。此文就近年来HCMV糖蛋白及不同亚型致病性研究进行了综述。     

The development of a hospice junior volunteer program

In the United States, volunteer services are mandated by hospice Medicare guidelines; volunteers provide a very valuable service to patients, families, and other members of the interdisciplinary team. A hospice junior volunteer program can engage teens in the care of the dying in our communities. This article describes the development and implementation of a junior volunteer program at St. Thomas Hospice in Hinsdale, Illinois.     

The effects of volunteering on the young volunteer

This article reviews some of the best researched volunteer service programs for adolescents and addresses three major questions: 1) What do existing data tell us about the effectiveness of community volunteer service programs in positively influencing the lives of the participants? 2) What do we know about why such programs work? 3) What are the most promising directions for future research and programming efforts to pursue? The review suggests that diverse, successful volunteer programs for adolescents, along with school-based support, are related to improvements in both the academic and social arenas. Specifically, volunteering relates to reduced rates of course failure, suspension from school, and school dropout, and improvement in reading grades; to a reduction in teen pregnancy; and to improved self-concept and attitudes toward society. The conditions under which the volunteering occurs, such as number of hours and the type of volunteer work, seem in some cases to be important to these outcomes, as does the age of the student volunteer; however, much is yet to be understood about these factors.     

化学实验教学中培养学生的环保意识

本文鉴于目前严重的环境污染问题,笔者建议化学教学中通过演示实验的后处理,药品的定量化,改进实验、实验的微型化、妥善处理化学实验的废弃物、增加环境实验内容,以及参观附近的一些工厂,培养学生的环保意识。     

Elimination of 1-hydroxypyrene after human volunteer exposure to polycyclic aromatic hydrocarbons

The aim of this study was to estimate the kinetics of 1-hydroxypyrene (1-HP) elimination after inhalation exposure to polycyclic aromatic hydrocarbons (PAHs). Samples of inhaled and exhaled air were collected on glass fiber filters backed with tubes filled with Amberlit XAD-2 resin. The filters were extracted by cyclohexane and Amberlit – by acetonitrile. Extracts for the determination of pyrene and benzo[a]pyrene (B[a]P) concentrations were analyzed by high-performance liquid chromatography (HPLC). 1-Hydroxypyrene in urine was determined after its preconcentration on a C-18 column (solid phase extraction method) using the same analytical technique. Five male volunteers were exposed for 6 h (two times, with a 1-month interval) to a PAH mixture at an aluminium plant. The volunteers were breathing at rest through facial mask equipped with a 1000-ml compensation container which allows collection of the exhaled air. Inhaled air samples were collected in the breathing zone of each volunteer. Urine samples were collected until the 71st hour after the onset of exposure. The average respiratory retention of pyrene was found to be 61%. The 1-HP elimination process could be described by one-compartment model with the half-live of 9.8 hour (95% CI 7.9–11.7 h). The simulation of 1-HP elimination in urine during a working week (4 days) indicates that the balance between absorption and elimination is achieved at the end of the second day. Received: 29 July 1996 / Accepted: 21 February 1997     

Live oral cholera vaccine: report of a trial on human volunteer subjects

Earlier laboratory studies on the possibility of basing a live oral cholera vaccine on a naturally avirulent strain of El Tor vibrio have shown that the strain is capable of multiplication in the gastrointestinal tract of rabbits resulting in the production of antibacterial and antitoxic immunity. In order to examine the safety and immunogenic value for human use of this proposed vaccine, a systematic trial has been carried out on 25 human volunteers. Following oral administration of the vaccine after neutralization of gastric acidity, the volunteers developed statistically significant increases in their vibriocidal antibody level. Copro-antibodies could also be demonstrated in stool samples within a week of vaccination Serum and copro-antibody levels persisted unchanged during the periods of observation of 6 and 3 months, respectively. None of the volunteers suffered any ill effect during the course of the trial. It has been concluded that the proposed vaccine is safe for human use and likely to protect against infection, although its protective value has still to be confirmed in a field trial.     

The buddy volunteer commitment in AIDS care.

Buddy volunteers provide crucial assistance to people with HIV-related illnesses. Based on volunteers' self-administered questionnaires, our study describes the nature of buddy work. Volunteers indicated their satisfaction with both personal performance and buddy program administration. Several factors were associated with volunteer satisfaction. This report is a first attempt to describe this special relationship created in response to the human immunodeficiency virus (HIV) epidemic.     

The hospice volunteer: a person of hospitality.

Volunteers are integral members of the hospice interdisciplinary team. They are distinguished from other members of the team only by role, not by expectation. The distinction is not between "volunteer" and "professional," because every team member is to be professional in the best sense of that word. If a distinction is to be made, it is that some hospice staff members are salaried while others donate their services. Volunteer staff members are expected to be as responsible and accountable as every other member of the team. ALL staff members must realize the importance of taking care of personal needs in order to be able to care for others. Even though the following article deals primarily with the volunteer hospice staff member, the points outlined can just as easily be applied to the salaried staff member.