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PubMed2006

Intention to register as organ donors: a survey of adolescents.

BACKGROUND: Little is known about factors that influence the intention of adolescents to register as organ donors. The identification of such factors has important implications for the development and implementation of educational programs and subsequent donor registration rates. OBJECTIVE: To determine whether adolescents with an expressed commitment to becoming organ donor registrants differ significantly from nondonors on sociodemographic characteristics and factors influencing their decision. PARTICIPANTS: Four hundred forty-five adolescents visiting a Department of Motor Vehicles office for a permit or license (n=153) or attending a driver's education course (n=292) completed a semistructured interview and questionnaire. RESULTS: Female (52.6%) and white (55.8%) adolescents were more likely to have favorable donation intentions relative to male (45.6%) and nonwhite (39.0%) adolescents (chi2 = 7.5, P = .02, and chi2 = 19.7, P = .003, respectively). Those with favorable donation intentions also endorsed significantly more positive factors (benevolence, need awareness, existentialism) as being more important in their decision. Adolescents who did not want to donate (58.7%) and those who were undecided (23.1%) were less likely to have discussed their decision with parents than were those who wanted to donate (67.7%, chi2 = 63.6, P = .0001). Finally, providing adolescents with a free driver's license in exchange for organ donor registration would have the greatest impact on registering undecided adolescents (29.8%, chi2 = 33.2, P = .0001). CONCLUSIONS: There is a pressing need for more systematic and culturally sensitive organ donation education directed toward adolescents, and the Department of Motor Vehicles and driver's education courses may be appropriate venues. An educational program from the U.S. Department of Health and Human Services, Decision: Donation, could be used in this context.

Adolescent↗

PubMed1996

[Use of related live donors in renal transplantation].

Collecting pertinent information is first step in assessing the use of living-related kidneys for transplantation. Current bioethics legislation in France limits kidney donation to first-degree family members and spouses in emergency situations. Severe penalties are inflicted for use of other donors or sale of organs. Further valuable information can be obtained from reports in the literature on complications in donors and on the advantages of living donor organs. The proportion of live donors in France is small (3.5% from 1984 through 1993) indicating that transplantation teams prefer cadaver organs except in pediatric cases. The proportion of live donor organs transplanted in northern Europe and North America is much higher. A quick survey of French teams show that opinions and practices vary. Questions still under debate include how to guarantee freedom to refuse or accept, a freedom directly related to correct information. Several propositions have been made in an attempt to harmonize management. First, an information sheet could be distributed during the early discussions, outlining the advantages and disadvantages of live organ donation. A list of complementary examinations could also be established to identify possible contraindications for nephrectomy and define exclusion criteria. A similar procedure adopted by all transplantation teams could be based on these propositions presented in the appendix. Potential donors could then benefit from uniform protection.

Family↗

PubMed2006

Alternate structural conformations of Streptococcus pneumoniae hyaluronan lyase: insights into enzyme flexibility and underlying molecular mechanism of action.

Streptococcus pneumoniae hyaluronan lyase is a surface enzyme of this Gram-positive bacterium. The enzyme degrades several biologically important, information-rich linear polymeric glycans: hyaluronan, unsulfated chondroitin, and some chondroitin sulfates. This degradation facilitates spreading of bacteria throughout the host tissues and presumably provides energy and a carbon source for pneumococcal cells. Its beta-elimination catalytic mechanism is an acid/base process termed proton acceptance and donation leading to cleavage of beta-1,4 linkages of the substrates. The degradation of hyaluronan occurs in two stages, initial endolytic cuts are followed by processive exolytic cleavage of one disaccharide at a time. In contrast, the degradation of chondroitins is purely endolytic. Structural studies together with flexibility analyses of two streptococcal enzymes, from S.pneumoniae and Streptococcus agalactiae, allowed for insights into this enzyme's molecular mechanism. Here, two new X-ray crystal structures of the pneumococcal enzyme in novel conformations are reported. These new conformations, complemented by molecular dynamics simulation results, directly confirm the predicted domain motions presumed to facilitate the processive degradative process. One of these new structures resembles the S.agalactiae enzyme conformation, and provides evidence of a uniform mechanistic/dynamic behavior of this protein across different bacteria.

Catalytic Domain↗

PubMed1990

Record health care directives before terminal illness!

Physicians share the grief and tension of families who must make decisions for incompetent, dying members. The author recorded the wishes of 1000 competent patients to guide families and the health care team during terminal illness. A questionnaire, which became part of the medical record, was used to determine views of organ donation, religious beliefs, and other directives. Patients were eager to record and discuss their wishes during an office or hospital visit; 94% of all patients wanted to participate in health care decisions. When directives for terminal care are available, families will not be forced to make blind crisis decisions for a dying member.

Adolescent↗

PubMed1995

Nitric oxide and reactive oxygen species in vascular injury.

Nitric oxide (.NO), a free radical species produced by several mammalian cell types, plays a role in regulation of vascular, neurological and immunological signal transduction and function. The role of .NO in cytotoxic events is acquiring increased significance. The high rate of production and broad distribution of sites of production of .NO, combined with its facile direct and indirect reactions with metalloproteins, thiols and various oxygen radical species, assures that .NO will play a central role in regulating vascular, physiological and cellular homoeostasis, as well as critical intravascular free radical and oxidant reactions. At the same time, there are contradictions as to whether .NO mediates or limits free-radical-mediated tissue injury, and uncertainty regarding its mechanisms of action. .NO has been portrayed as a pathogenic mediator during ischaemia-reperfusion, and inflammatory and septic tissue injury. In contrast, cell-, metal- and oxidant-induced lipoprotein oxidation events, as well as hepatic, cerebrovascular, pulmonary and myocardial inflammatory and ischaemia-reperfusion injury studies, show convincingly that stimulation of endogenous .NO production or exogenous administration of .NO-donating molecules can serve a protective role by inhibition of often oxidant-related mechanisms. The final outcome of toxic versus tissue-protective reactions of .NO will depend on several factors, including sites and relative concentrations of individual reactive species and their diffusion distances. The following sections address these issues and conclude with a proposal as to how .NO serves as a central regulator of oxidant reactions and diverse free radical-related disease processes.

Animals↗

PubMed2004

Transmission of donor melanoma to multiple organ transplant recipients.

Malignant melanoma represents the most common tumour responsible for donor-derived post transplantation malignancies. We report the varied presentation and outcome of three graft recipients (two kidney and hepatic) who developed metastatic melanoma following cadaveric organ transplantation from a single multiorgan donor. Two of the recipients presented with symptomatic metastatic lesions and the third patient, despite being carefully monitored, developed evidence of metastatic cutaneous melanoma. Two of the patients died as a direct result of their melanomas. The recipients of corneal and cardiac grafts remain disease-free. We conclude that despite careful screening, donor-derived tumours remain a not uncommon clinical entity. The identification of a lesion in one recipient should prompt immediate examination and investigation of the remaining recipients of multiorgan donations.

Adult↗

PubMed2001

Is there evidence for preferential delivery of ovarian estradiol to the endometrium?

OBJECTIVE: To determine the direction of delivery of E(2) in the female pelvis by assessing the ratio of endometrial to serum E(2) in women whose ovaries were stimulated to produce E(2) with women who received exogenous E(2). DESIGN: Prospective comparative study. SETTING: University-based ART program. PATIENT(S): Oocyte donors and recipients of donor oocytes. INTERVENTION(S): Micronized E(2) administered by the oral or vaginal route and oocyte donation. MAIN OUTCOME MEASURE(S): Serum and endometrial levels of E(2). RESULT(S): Serum E(2) levels were significantly higher in women who underwent controlled ovarian hyperstimulation (COH) and women receiving exogenous E(2) by the vaginal route than in those who received oral E(2). Levels of E(2) in endometrial tissue were similar in women who underwent COH and those receiving oral E(2). Endometrial E(2) levels in women who underwent vaginal administration were significantly higher than those in the oral E(2) or COH groups. The ratio of endometrial to serum E(2) was highest in women who underwent vaginal E(2) and lowest in those undergoing COH. CONCLUSION(S): Vaginal administration of micronized E(2) results in preferential absorption of E(2) into the endometrium, consistent with a "uterine first pass" effect. Since endogenous E(2) produced the smallest ratio of E(2) between the endometrium and serum, E(2) produced by the ovaries is not preferentially delivered to the uterus.

Administration, Oral↗

PubMed1992

Ethical considerations in living organ donation and a new approach. An Advance-Directive Organ Registry.

Living organ donation should be recognized as an ethical compromise to the principle of nonmaleficence (doing no harm), given the risks healthy donors are allowed to assume. Living organ donation should be reserved for situations in which there is no acceptable alternative. Increasing the availability of cadaveric organs is most desirable, since it would decrease (although probably not eliminate) the need for living organ transplantation and would provide organs (ie, hearts) that could not otherwise be obtained. We propose the development of an incentive-based Advance-Directive Organ Registry, in which all adults are encouraged to register their advance directive regarding organ donations. Those individuals agreeing to permit usable organs to be taken at the time of death would receive priority for organs generated by the program, should a transplant become necessary when there is a shortage of organs. The proposed Advance-Directive Organ Registry is firmly founded on the principles of autonomy, beneficence, and justice.

Advance Directives↗

PubMed2005

[Some problems on the organ transplantation in Japan from the viewpoint of the neurocritical care units].

The authors have referred to several issues encountered in the neuroemergency and critical care facilities in our country through the declaration of brain death to the successful removal of organs for donation. One of the most important is the fact that the legal validity of death in brain dead patients is only assured when the patient shows the advance directive for organ donation in Japan. So far as the selection of the recipient is not started until the brain death is declared legally, longer than 12 hours are to be spent in vain between the declaration of brain death and the beginning of the operation of removing the organs for donation. As there remain such several problems to be solved as mentioned above for organ donation in Japan, so it is suggested that the medical sciences and ethics should be respected and adopted in the rules for the organ donations by the national government.

Brain Death↗

PubMed2001

The consent process for cadaveric organ procurement: how does it work? How can it be improved?

CONTEXT: Understanding the consent process that organ procurement organizations (OPOs) use is crucial to improving the process and thereby reducing the number of individuals who die each year for want of an organ transplant. However, no data exist on OPOs' current consent practices. OBJECTIVE: To assess whose wishes OPOs follow when procuring solid organs from deceased individuals and whether advance directives and computerized registries might improve the consent process for solid organ procurement. DESIGN, SETTING, AND PARTICIPANTS: Telephone survey conducted from June to August 1999 of all 61 active OPOs. MAIN OUTCOME MEASURES: Responses to the 49-question survey addressing consent practices in specific scenarios of deceased and next of kin wishes. RESULTS: Widespread divergence exists in OPOs' consent practices for cadaveric solid organ procurement. Regarding overall consent practices, 19 (31%) OPOs reported that they follow the deceased's wishes, 19 (31%) follow the next of kin's wishes, 13 (21%) procure organs if neither party objects, 8 (13%) procure organs if either party consents or neither objects, and 2 (3%) do not follow any of these 4 overall practices. These differences appear to be traceable to implicit ethical disagreements about whose wishes should be followed. A total of 29 (48%) OPOs reported having an official policy to address whether they follow the family's or deceased's wishes. Regarding factors that influence OPOs' choice of consent practice, 29 (48%) respondents ranked impact on the deceased's family as the most important factor, 13 (21%) ranked state law as most important, and 7 (11%) ranked the priority of the deceased's wishes as most important. Durable power of attorney appeared to have substantial weight in OPOs' decisions; for example, in the scenario in which the deceased supported organ donation and the next of kin opposed it, 34 (56%) OPOs reported they were likely to procure organs based on the consent of the holder of the deceased's durable power of attorney, whereas only 7 (11%) reported they were likely to procure organs based on a document of gift (a living will, donor card, or driver's license). CONCLUSIONS: Expanding the legal scope of living wills to cover individuals' organ donation preferences would likely have little impact on procurement rates. In contrast, expanding the legal scope of durable powers of attorney for health care may have a significant impact. A national discussion should take place addressing the underlying ethical issues that appear to account for much of the divergence among OPOs' consent practices for cadaveric solid organ procurement.

Advance Directives↗

PubMed2002

Quantitation of choline and its metabolites in tissues and foods by liquid chromatography/electrospray ionization-isotope dilution mass spectrometry.

Choline is important for normal membrane function, acetylcholine synthesis, lipid transport, and methyl metabolism. The U.S. National Academy of Sciences recently set requirements for choline in the human diet. In tissues and foods, there are multiple choline compounds that contribute to choline content. Betaine, a derivative of choline, is also important because of its role in donation of methyl groups to homocysteine to form methionine. Radioisotopic, high-pressure liquid chromatography, and gas chromatography/isotope dilution mass spectrometry (GC/IDMS) methods are available for measurement of choline. However, these existing methods are cumbersome and time-consuming, and none measures all of the compounds of interest. In this study, we describe a new method for quantitation of choline, betaine, acetylcholine, glycerophosphocholine, cytidine diphosphocholine, phosphocholine, phosphatidylcholine, and sphingomyelin in liver, plasma, various foods, and brain using liquid chromatography/electrospray ionization-isotope dilution mass spectrometry (LC/ESI-IDMS). Choline compounds were extracted by and partitioned into organic and aqueous phases using methanol and chloroform and analyzed directly by LC/ESI-IDMS without the need for isolation and derivatization of each compound separately as was required by the GC/IDMS method. The new LC/ESI-IDMS method was validated using the existing published GC/IDMS method.

Brain↗

PubMed2005

Impact of a "direct approach" to live kidney donation in the British Indo-Asian community.

Although a general imbalance exists between the demand for renal transplants and the supply of suitable organs, the shortfall is particularly severe for patients from the Indo-Asian (I-A) community. It seems unlikely that this will be remedied by any increase in cadaveric donation. Our aim was to increase the rate of live donor transplantation (LDT) in the I-A population through a direct approach to patients and their families, in a culturally acceptable environment by an Asian transplant coordinator. Whereas an increase in LDT was seen in the I-A population over the period of review, 1997 to 2003, 15 compared with none prior to 1997, significant attrition was seen within the program, with only 10% of the original cohort coming to donation. There are multiple reasons for this including medical, social and psychological.

Asia↗

PubMedDate not supplied

Personality characteristics, body image and social attitudes of organ transplant donors versus nondonors.

Thirty adults willing their body at death to medical science were compared on a number of personality variables with 30 nondonors, both groups equated for age, education, and socioeconomic status. Donors are internally directed, masters of their fate; nondonors rely on chance or luck to explain outcome. A more definite body image characterizes donors while nondonors are more concerned about body integrity. Donors accept their mortality while nondonors worry more about death. At the fantasy level donors display more hostility, depression, and guilt, and the prospective act of donation may represent an attempt at atonement. Donation represents a convenient and socially acceptable outlet for expression of humanitarian needs by donors.

Adult↗

PubMed1996

Who pays for failed organ procurement and what is the cost of altruism?

Our objective was to define medical complications and financial charges generated during the care of potential solid organ donors who fail to donate after consent has been obtained. A retrospective review of financial and medical records of potential organ donors was done at an urban level 1 trauma center. Total hospital stay (T1+T2) for the group was broken down into the interval between admission and diagnosis of lethality (T1) and between diagnosis of lethality and death (T2). Medical complications occurring during the hospital stay and charges generated during each time interval were abstracted. After consent was obtained, 19 of 53 (36%) potential donors failed to donate: 9 of 19 (47%) expired prior to legal determination of brain death; 10 patients failed to progress to brain death and were made DNR. Of these, 9 died within 24 hr, 1 survived 16 days; 6 of the 10 patients did not meet brain death criteria, and 4 were rejected by the OPO for reasons of infectious risks. There were 3.1+/-1.3 medical complications per patient. T1 was less than 4 hr in 16/19 (84%) potential donors and constituted a small percentage of the mean total hospital stay (37+/-10 hr). Charges generated during T1+T2 (33,997+/-25,843) and specifically during T2 (17,385+/-9453) were considerable. These charges were passed on to patients' families or third party payers though care was directed solely at organ procurement after diagnosis of lethality. We conclude that multiple medical complications are encountered in the care of potential organ donors; total hospital stays are short but expensive; more than 50% of charges generated during the total hospital stay arise from care provided after determination of lethality; and the goodwill of families to consent to organ donations of their loved ones appears to carry potential for significant financial burden.

Altruism↗

PubMed2006

Altruistic living donors: evaluation for nondirected kidney or liver donation.

A program was established within our regional procurement organization to permit evaluation of altruistic living donors (LD) interested in nondirected kidney or liver segment donation prior to transplant center referral. During the initial 30 months of program operations, 731 donor inquiries were received of which 131 individuals called back after review of mailed information materials. Forty-seven candidates initiated and 19 completed the evaluation process. Seven underwent donation to include six kidneys and one liver segment, five are actively pending donation, five were excluded from donation following transplant center evaluation and two took no further action after their intended liver recipients received deceased donor (DD) transplants. Psychological evaluation of these 19 candidates found them to be free of psychopathology, highly cooperative and self-directed. They did not exhibit attention-seeking or religious motivations for their actions. All seven donors and recipients continue to do well postoperatively. This evaluation program has made possible large-scale screening and education of prospective altruistic LD within the general population and also provides a unique opportunity to further our understanding of those individuals interested in living-nondirected donation.

Adult↗

PubMed1986

Primary brain tumours in Fischer 344 rats chronically exposed to acrylonitrile in their drinking-water.

Acrylonitrile (ACN) has been tested for carcinogenicity by various routes in a number of rat strains. At relatively high levels of administration (e.g. 500 ppm in the drinking-water) there were statistically significant increases in microscopically detectable primary brain tumours, which were difficult to classify. In a further study of ACN-induced brain tumours, ACN was administered to groups of 50 male and 50 female F-344 rats from 6 wk of age at levels of 0, 100 and 500 ppm in the drinking-water. A fourth group of 300 rats (147 males, 153 females), was also given 500 ppm ACN. Neurological signs were observed in 0, 4, 16 and 29, respectively, of the rats in these four groups within 12-18 months. Among the treated animals, females died slightly earlier than males. Few controls of either sex had died by month 18, but, apart from those killed for tumour donation, a high proportion of the rats in the 500-ppm groups had died by that time. Of the 49 brain tumours found in rats exposed to 500 ppm ACN, 11 were only detectable microscopically, 28 were 1-5 mm in diameter and 10 were greater than 5 mm. Despite this variation in size, all the tumours were similar in cellular and architectural features. They were densely cellular, with occasional areas of focal necrosis, and were infiltrative at the margins. They were negative for glial fibrillary acidic protein (GFAP). Ultrastructurally, the tumour cells showed intermingling cytoplasmic processes but no glial filaments and no neurosecretory granules or specialized cell contacts. Samples of tumour tissue were successfully grown in culture, but transplantation of samples from these cultures (observed for up to 12 wk) was unsuccessful. However, a direct intracerebral transplantation from a large tumour was successful.

Acrylonitrile↗

PubMed1986

Living-related kidney donors: a multicenter study of donor education, socioeconomic adjustment, and rehabilitation.

To determine the consequences of living-related kidney donation, a study was conducted of 536 donors whose nephrectomies had been performed at nine geographically dispersed centers during the past 12 years. The data demonstrated that greater than 84.0% of the donors thought they had been adequately informed regarding all aspects of donation, and less than 15.0% reported being pressured in their decision. Only two serious medical complications were directly attributable to the surgery, greater than 92.0% of the donors believed their health had not been adversely affected by donation, and 96.8% reaffirmed their decision regardless of the graft's success or the financial distress they experienced (P greater than .05). However, greater than 14.0% experienced direct pressure, particularly not to donate. Donation also appeared to stress previously troubled marriages, especially among donors without a religious affiliation, who were pressured to donate by their families, or who borrowed from family members (P less than .05). Substantial unreimbursed expenses (greater than or equal to $1,000) were incurred by 43 donors, and 23.2% of all donors reported that donation caused a financial hardship.

Adolescent↗

PubMed2006

Effect of donor variables on yield in single donor plateletpheresis by continuous flow cell separator.

The quality of single donor platelets (SDPs) in terms of yield influences platelet recovery in the recipient. Various donor factors such as pre-donation platelet count and hemoglobin (Hb) concentration affect the platelet yield. We studied the influence of pre-donation donor clinical and laboratory factors such as gender, age, weight of the donor, platelet count and Hb on the platelet yield. A total of 94 plateletpheresis procedures performed on continuous flow cell separator (CS3000, Baxter Healthcare, Round Lake, IL, USA) were evaluated for platelet yield. A relationship between pre-donation donor variables and yield of platelets was studied using the Pearson correlation. The mean platelet yield was 2.8+/-0.73x10(11). While a direct relationship was observed between pre-donation platelet count and yield (r=0.50, p<0.001), no such correlation was noticed with donor Hb concentration (r=-0.10, p>0.005). Similarly, no correlation was observed between gender (r=0.05), age (r=0.11) and weight (r=0.18) of the donor with yield. Optimization of platelet yield, which is influenced by pre-donation platelet count, is an emerging issue in blood transfusion services. Identification of such factors may help in selecting donors to obtain higher platelet yields and consequently better clinical outcome.

Adult↗