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Gas-chromatographic method of analysis for urinary organic acids. II. Description of the procedure, and its application to diagnosis of patients with organic acidurias.

A gas-chromatographic method for urinary organic acid analysis is described, designed to be used routinely for the diagnosis of organic aciduria. It involves extraction of urine with ethyl acetate, dehydration of extract residues, and trimethylsilylation. Organic acids are identified by using an extensive list of retention indices published in the accompanying paper (this issue). Quantitative values are given for organic acids in urines from 50 ostensibly normal subjects. Typical chromatograms of urinary organic acids from patients with eight well-established organic acidurias are also shown.

Acids↗

Accumulation of organic anion in intracellular vesicles of cultured rat hepatocytes is mediated by the canalicular multispecific organic anion transporter.

Transport of organic anions within hepatocytes and the possible involvement of intracellular vesicles were studied with fluorescence microscopy. For this purpose monochlorobimane, a nonfluorescent hydrophobic compound that readily permeates into cells and is conjugated with glutathione to form the fluorescent glutathione bimane, was used. In the isolated perfused livers of normal rats, glutathione bimane is rapidly secreted into bile. In contrast, in our study of livers from mutant TR- rats, a 100-fold reduction in glutathione bimane secretion into bile occurred. Mutant TR- rats have an inherited defect in the canalicular multispecific organic anion transporter, which mediates the ATP-dependent secretion of a wide range of organic anions over the canalicular membrane into bile. When cultured Wistar and TR- hepatocytes were loaded with glutathione bimane, both cell types displayed a strong cytosolic fluorescence. Wistar cells completely lost this cytosolic fluorescence at incubation on monochlorobimane-free medium because of secretion of glutathione bimane. A clear punctate fluorescence remained, however, which was scattered through the cell with some perinuclear concentration. In some cells vesicular fluorescence was also concentrated around a canaliculus. In contrast, TR- cells lost their cytosolic fluorescence more slowly and completely lacked the vesicular fluorescence. Making cells selectively permeable with digitonin directly after loading them with glutathione bimane to remove cytosolic fluorescence again revealed the presence of fluorescent vesicles in Wistar cells and their absence in TR- cells. In Wistar cells vesicular fluorescence could be increased by preincubation with monensin or methylamine, compounds that have been shown to interfere with plasma membrane recycling. In conclusion, these results suggest that apart from secretion over the plasma membrane, the canalicular multispecific organic anion transporter may be involved in accumulation of organic anion in intracellular vesicles. It is hypothesized that this intracellular localization of the canalicular multispecific organic anion transporter is caused by recycling of the transporter between the plasma membrane and intracellular membranes.

Adenosine Triphosphate↗

The biphasic effect of organic cations on the excretion of other organic cations.

The renal excretion of 14C-choline or 14C-acetylcholine was increased by the infusion of another organic cation at low rates but was decreased by infusion of the same added organic cation at higher rates with the Sperber technique in hens. The range of low rates of infusion was from 1 X 10(-15) to 1 X 10(-8) mol/min. At infusion rates greater than 1 X 10(-8) mol/min, inhibition of tubular excretion was found. At the low infusion rates, thiamine, lysine, quinine, atropine, acetylcholine and methylguanidine were found to increase 14C-choline excretion. The same compounds with the exception of lysine and acetylcholine inhibited 14C-choline excretion at the higher infusion rates. A biphasic effect on 14C-acetylcholine excretion was also observed with added atropine, thiamine and choline over the same infusion range. Increases in 14C-choline excretion occurred during a choline infusion rate that normally produced an excretory tubular maximum for choline whereas increases in 14C-acetylcholine excretion occurred during infusion of tracer amounts of 14C-acetylcholine. The effect of the addition of organic cations was selective for cations since the tubular excretion of organic anions was not affected by the addition of organic cations. The tubular excretion ratio of 14C-thiamine/p-aminohippuric acid increased from 0.25 to 0.95 when the infusion rate of added unlabeled thiamine was increased from 1 X 10(-11) to 1 X 10(-8) mol/min. Enhanced tubular excretion of 14C-thiamine may represent the effect of the increased load of unlabeled thiamine to protect the labeled thiamine from conversion to a nontransportable metabolite. Enhancement of excretion of 14C-choline and 14C-acetyocholine produced by very small amounts of other organic cations may represent either inhibition of tubular reabsorptive transport or induction of tubular excretory transport.

Acetylcholine↗

Scanning electron microscopy of the electric organs of Electrophorus electricus L. II. Organs of Sachs and Hunter.

The surfaces of the organs of Sachs and Hunter of Electrophorus electricus L. were examined by scanning electron microscopy. Special attention was directed to morphological details of the electrocyte to provide a better understanding of its anterior and posterior faces. Some aspects of the microanatomy of these organs, which differ markedly from those of the main electric organ, provide new information on the structure as revealed previously by light and transmission electron microscopy. The relief, mainly expressed by papillae, is related to the actual membrane area, which is important for calculations of specific resistance and conductance. Information is also presented on the general organization of the tissue, in particular the distribution of the connective elements and external configuration of synaptic terminals. Shrinkage in preparation of tissue was evaluated and correction made whenever necessary. Correction factors for actual membrane area were calculated for anterior and posterior faces of electrocytes from both organs.

Animals↗

Replication of arboviruses in mouse organ cultures. II. Multiplication of virulent and avirulent Semliki Forest and western equine encephalitis viruses in mouse organ cultures.

The titre of WEE virus produced by organ cultures of brain, muscle and spleen decreased as tissue was taken from older mice. The multiplication of SFV and SFA in muscle organ cultures of mice remained nearly constant, whereas in spleen organ cultures, titers of both viruses decreased with increasing age of mice. There was a striking difference in the rate of decline of the yield of brain organ culture infected with virulent and avirulent SF virus strains. Organ cultures made from the brains of mice over 16 days old were totally resistant to SFA infection, whereas similar cultures from mice up to 42 days of age supported SFV multiplication. These results show that the avirulence of this strain of SF virus is due to age related intrinsic brain insusceptibility.

Age Factors↗

Are personnel in transplant hospitals in favor of cadaveric organ donation? Multivariate attitudinal study in a hospital with a solid organ transplant program.

INTRODUCTION: A considerable number of professionals who work in a hospital could be against organ donation, which means that when the time comes, they could act as an obstacle to donation. The objective of this study was to analyze the attitude of hospital professionals toward organ donation and to determine the factors that influence this attitude in a Spanish center with a transplant program. MATERIALS AND METHODS: The study was carried out in a third-level Spanish hospital with a solid organ transplant program. A random sample was taken (n = 1262) and stratified by job category and type of service. Attitude was evaluated using a validated questionnaire. Contact was made in each service with the person responsible for each of the job categories in order to distribute the survey. The survey was completed anonymously and was self-administered. Student's t-test, the chi-squared test, and logistic regression analysis were applied in the statistical analysis. RESULTS: The survey completion rate was 93% (n = 1168). Most respondents were in favor of donation [69% (n = 808)]. Of those who are not in favor, 29% (n = 105) provide fear of apparent death as the reason whilst most do not give a reason (negative assertion; 57%; n = 206). There are many factors related to this attitude toward donation, which are evident in the multivariate analysis: (i) job category, in which physicians are twice as likely to be in favor of donation than ancillary personnel (OR = 2.02); (ii) a respondent's knowledge of brain death (OR = 1.64); (iii) having discussed the matter of organ donation and transplantation within the family (OR = 1.89); (iv) a preference for other options apart from burial (OR = 3.66); (v) being in favor of the performance of autopsy if it were necessary (OR = 2.76); (vi) not being concerned about mutilation of the cadaver (OR = 2); and (vii) having a partner with a favorable attitude toward donation (OR = 2.2). CONCLUSIONS: Attitude toward cadaveric organ donation among personnel in a transplant hospital is similar to that described in the general public and is determined by many factors. The following factors are most noteworthy: (i) job category; (ii) knowledge of the concept of brain death; (iii) consideration of the matter of donation in the family; and (iv) fear of manipulation of the cadaver. In view of this attitude, which is similar to that of the general public, it is necessary to carry out promotion activities if we want to increase cadaveric donation rates.

Adult↗

A statewide public health approach to improving organ donation: the Massachusetts Organ Donation Initiative.

Despite the growing disparity between organ supply and demand in the United States, few initiatives have attempted to close the gap through systematic population-based public health endeavors. We examined the evolution, implementation, and outcomes of the Massachusetts Organ Donation Initiative, a statewide effort that included a unique partnership among organ procurement organizations, major teaching hospitals, and the state's department of public health. Lessons from this initiative have contributed to growing national efforts for increasing organ supply and have provided insights for addressing this continuing public health challenge.

Cooperative Behavior↗

[The Organ Donation Law: changes in the procurement of organs and tissues for transplantation].

The Organ Donation Act fills an old gap in the legislation, leading to improvement of the legal position of those involved. Much attention is given to the protection of the potential donor. A new consent procedure is introduced, including the registration of the consent or refusal of all persons aged 18 years or older. Because of the persistent shortage of donor organs the noncommittal nature of organ procurement is changed. Hospitals and nursing homes are obliged to have a protocol for organizing tissue donation. Also, conditions have been created for a just division of the available organs and tissues for transplantation.

Adolescent↗

The New England Organ Bank--lessons from running a regional organ bank.

1. The NEOB is a very large organ procurement organization (OPO) recovering multiple organs and tissues on behalf of 15 transplant centers serving 11.5 million people scattered over 6 states. 2. The database maintained by the New England Organ Bank (NEOB) demonstrates a changing pattern of donors within our region. Trauma is decreasing as a cause of death and the age of donors is steadily increasing. 3. A flexible system for the allocation and distribution of kidneys is described. This system emphasizes waiting time as the primary criterion for allocation. This emphasis has not disadvantaged the highly sensitized patient and is equitable for minority recipients. The use of the longest waiting unsensitized patient to assign donors to transplant centers maintains the patient-based nature of the system, while allowing transplant centers to recover kidneys for their own patients and reducing ischemic time. The system is highly adaptable to a variety of local situations. 4. Extensive public education and research projects not feasible for small organizations are made possible through the resources available to a large OPO.

Health Care Rationing↗

Multiple organ dysfunction syndrome: end organ and systemic inflammatory response in a mouse model of nonseptic origin.

The authors measured the peripheral blood pro-inflammatory cytokine responses (tumor necrosis factor-alpha [TNF-alpha] and interleukin-6 [IL-6]) and related end organ responses ti intraperitoneal zymosan-saline suspension over 5 days in CD-1 mice. Other indicators of local and systemic inflammation included wet:dry weight ratios of lung, liver, kidneys, spleen, and bowel; peripheral blood hematocrit, white blood cell count, and platelet count; lung myeloperoxidase activity; lung protein leak; and bacterial translocation to liver, spleen, and mesenteric lymph nodes. The initial event in responses to zymosan A injection was a sharp rise in the peripheral blood TNF-alpha level, which crested within 1 h of injection. This response was followed by a peripheral blood leukocytosis also within 1 h, and a peak lung myeloperoxidase activity within 1-2 h of injection. The maximum lung permeability index occurred 8 h after injection (zymosan, .398 +/- .019 [n = 10]; saline vehicle, .266 +/- .007 [n = 10], p < .001) followed by the maximum lung wet:dry weight ratio, which occurred 18 h after injection. The peak wet:dry weight ratios for the other organs occurred between 12 and 24 h after injection as well. Peripheral blood IL-6 maxima followed TNF-a maxima after lags of several hours. The release of pre-formed TNF-a is likely the most proximal event following injection of zymosan, and may set in motion the processes that result in end-organ injury and secondary multiple organ dysfunction, particularly activation of leukocytes. The precise roles of TNF-alpha and IL-6 in the pathogenesis of end-organ injury, however, are not addressed.

Animals↗

Multiple organ failure, multiple organ dysfunction syndrome, and systemic inflammatory response syndrome. Why no magic bullets?

The concept of multiple organ failure and related abnormalities was first developed in the 1970s. Multiple organ failure became evident when the support systems in intensive care units were able to keep patients alive long enough for multiple organ problems to develop in them. The high mortality of patients with multiple organ failure provided a focus for the problems that ultimately led to death for many patients in the intensive care unit. The frequency of infection, sepsis, or inflammation in producing multiple organ failure led to clinical trials of so-called magic bullets for the treatment of patients with sepsis. These trials have had either limited success or negative results, despite considerable evidence for efficacy or protection by such agents in experimental animals and in studies of normal human volunteers. I believe a major reason for these negative results has been the use of general entry criteria for the trials rather than the treatment of specific diseases or injuries.

Humans↗

Injurious mechanical ventilation and end-organ epithelial cell apoptosis and organ dysfunction in an experimental model of acute respiratory distress syndrome.

CONTEXT: Recent clinical trials have demonstrated a decrease in multiple organ dysfunction syndrome (MODS) and mortality in patients with acute respiratory distress syndrome (ARDS) treated with a protective ventilatory strategy. OBJECTIVE: To examine the hypothesis that an injurious ventilatory strategy may lead to end-organ epithelial cell apoptosis and organ dysfunction. DESIGN AND SETTING: In vivo animals: 24 rabbits with acid-aspiration lung injury were ventilated with injurious or noninjurious ventilatory strategies. In vitro: rabbit epithelial cells were exposed to plasma from in vivo rabbit studies. In vivo human: plasma samples from patients included in a previous randomized controlled trial examining a lung protective strategy were analyzed (lung protection group, n = 9 and controls, n = 11). MAIN OUTCOME MEASURES: In vivo animals: biochemical markers of liver and renal dysfunction; apoptosis in end organs. In vitro: induction of apoptosis in LLC-RK1 renal tubular epithelial cells. In vivo human: correlation of plasma creatinine and soluble Fas ligand. RESULTS: The injurious ventilatory strategy led to increased rates of epithelial cell apoptosis in the kidney (mean [SE]: injurious, 10.9% [0.88%]; noninjurious, 1.86% [0.17%]; P<.001) and small intestine villi (injurious, 6.7% [0.66%]; noninjurious, 0.97% [0.14%]; P<.001), and led to the elevation of biochemical markers indicating renal dysfunction in vivo. Induction of apoptosis was increased in LLC-RK1 cells incubated with plasma from rabbits ventilated with injurious ventilatory strategy at 4 hours (P =.03) and 8 hours (P =.002). The Fas:Ig, a fusion protein that blocks soluble Fas ligand, attenuated induction of apoptosis in vitro. There was a significant correlation between changes in soluble Fas ligand and changes in creatinine in patients with ARDS (R = 0.64, P =.002). CONCLUSIONS: Mechanical ventilation can lead to epithelial cell apoptosis in the kidney and small intestine, accompanied by biochemical evidence of organ dysfunction. This may partially explain the high rate of MODS observed in patients with ARDS and the decrease in morbidity and mortality in patients treated with a lung protective strategy.

Animals↗

Organ specificity of metastatic tumor colonization is related to organ-selective growth properties of malignant cells.

In cancers such as malignant melanoma, tumor spread or metastasis occurs preferentially to certain organ sites. Mouse B16 melanoma cell sublines that have been selected sequentially in vivo for enhanced blood-borne colonization of lung, brain, or ovary were tested for their survival and growth stimulation in vitro by soluble factors released from suspensions of mouse lung, brain, liver, ovary or kidney tissues. In general, the growth rate of lung-colonizing B16 cells was stimulated by high concentrations of lung-tissue-derived factors significantly more than by factors from the other tissues, whereas the growth rate of ovary-colonizing B16 cells was stimulated by ovary or lung-tissue-derived factors significantly more than by factors from the other tissues. In contrast, the growth of brain-colonizing B16 cells was not stimulated by factors released from brain tissue. When it occurred, stimulation of B16 cell growth by factors released from mouse organ tissues was dose-dependent. Liver tissue factors, and at high concentrations kidney tissue factors, inhibited cell growth of the B16 sublines, an inhibition correlating with the low potential of B16 cells to colonize liver and kidney in vivo. In addition to preferential target-organ cell adhesion found previously with B16 sublines (Nicolson et al., 1985a), the present results suggest that metastasis to specific organ sites is also dependent on the survival and growth of B16 cells affected by soluble organ-derived factors.

Animals↗

Consecutive organ transplantation in inbred rats: long-term results--Are organs recyclable?

Using 9-12-month-old Lewis rats, our laboratory performed consecutive organ transplantations to assess the technical feasibility and observe the histopathologies of prolonged transplants and implants over a rat's life span. This study includes a total of 688 cases of consecutive syngeneic organ transplantation, including pancreaticoduodenum (PD), en-bloc liver-pancreaticoduodenum-spleen-stomach (LPdSpSt), and spleen bearing ovary or testicle. A 52-month-old consecutively transplanted pancreas showed normal acini and islet cells. Consecutively transplanted LPdSpSt cases at 25-28 months preserved normal histology. After 26.5 months of ovarian follicle implantation into the spleen, the pathology of the organ exhibited typical dysgerminoma. However, 29.5-month-old infantile testicle implants in the spleen showed seminoma. Our studies suggest that transplanted organs can be reusable and retransplanted, and we hope this could be one of the clues to solve donor-organ shortages in the future.

Animals↗

Betaine is a highly effective organic osmolyte but does not appear to be transported by established organic osmolyte transporters in mouse embryos.

Betaine protects early preimplantation mouse embryos against increased osmolarity in vitro, functioning as an organic osmolyte. Betaine is effective at very low external concentrations, with half-maximal protection of 1-cell embryo development to blastocysts at approximately 50 microM, making it one of the best osmoprotectants for mouse preimplantation embryos. We performed studies designed to determine whether known high-affinity organic osmolyte transporters could account for the ability of betaine to act as an organic osmolyte in preimplantation embryos. We found no evidence in 1-cell embryos of transport by a betaine/GABA transporter (BGT1), the osmoregulated betaine transporter found in a number of cell types, as betaine and GABA did not inhibit each other's transport. Instead, all saturable GABA transport in embryos was apparently via the beta-amino acid transporter. We also found that the glycine transporter, GLY, which mediates osmoprotective transport of glycine in early preimplantation embryos, does not appear to transport betaine. Finally, increased osmolarity did not induce any detectable System A amino acid transporter activity, which is osmotically-inducible in other cells and can transport betaine. There does appear, however, to be a saturable betaine transporter in 1-cell mouse embryos, as considerable 14C-betaine transport was measured which was substantially inhibited by excess unlabeled betaine. Our data imply that betaine functions as an organic osmolyte in embryos due to its saturable transport via a mechanism distinct from known osmolyte transporters. We propose that an unidentified high-affinity betaine transporter may be expressed in early embryos and mediate transport of betaine as an organic osmolyte.

Alanine↗

Automated quantitative and isotopic (13C) analysis of dissolved inorganic carbon and dissolved organic carbon in continuous-flow using a total organic carbon analyser.

A method for the automated (13)C analysis of dissolved inorganic and organic carbon species has been developed to operate on a continuous-flow isotope ratio mass spectrometer (CF-IRMS). For natural and anthropogenic carbon species, the (13)C stable isotope has proven to be an excellent environmental tracer. Analytical performance tests were carried out on various organic compounds from easily oxidisable (sugar) to difficult (humic acid). A set of natural samples was also analysed to confirm the flexibility of the system. Analytical precision (2sigma) is typically <0.20 per thousand with sample reproducibility from 0.10-0.35 per thousand depending on reactivity of material. We believe this to be the first successful use of a total organic carbon (TOC) analyser for both dissolved inorganic and, specifically, dissolved organic species for (13)C stable isotope analysis in an automated CF-IRMS system. Routine analysis is achieved fairly quickly, is relatively simple with little or no sample manipulation, and will allow new and exciting studies for stable isotope research in both natural abundance and organic tracer studies not easily achieved before.

Carbon↗

B16 melanoma variants selected by one or more cycles of spontaneous metastasis to the same organ fail to exhibit organ specificity.

Metastatic clones of the mouse B16 melanoma spontaneously disseminate from subcutaneous tumors throughout the body in two stages, initially to the lungs and secondarily from established lung metastases to systemic sites. From the heterogeneous 'parent' B16 melanoma cell line and from two representative clones, G3.5 and G3.12, cell populations were selected after one or more cycles of tumor growth or metastasis to a particular site, to determine whether metastatic variants with greater organ preference or specificity could be generated. Variants with enhanced secondary metastatic activity were obtained only from G3.12 tumor-disseminated metastases growing in the lungs or in systemic organs. Regardless of the organ of selection or the number of selection cycles, all variants exhibited an overall increase in secondary metastasis incidence and burden in the brain, adrenals, kidneys and ovaries, but no organ preference or specificity was obtained. Populations that grew especially well in the brain, ovaries or liver following intravascular injection were either non-metastatic or exhibited no organ preference during spontaneous metastasis. The increased secondary metastatic activity of G3.12 variants was apparently not due to either longer host survival or to tumor-disseminated cells bypassing the lungs, but may result from enhanced growth potential or greater secondary dissemination capability imparted during growth as lung metastases.

Animals↗

Applicability of radiosurgery with heavy ion beams to inactivate specific organs in living organisms.

It was the aim of the study to test the applicability of radiosurgery in inactivating a specific organ through local irradiation with heavy ion beams. Silkworms were exposed to whole-body or local irradiation with carbon ion beams ((12)C(5+), 18.3 MeV/u, range=1.1 mm). After irradiation at the wandering stage, no significant differences were observed regarding either survival or cocoon quality between locally irradiated larvae and controls. Only localized effects were seen, such as the deletion of wings and functional disorders of the reproduction primordium, depending on both irradiation dose and site. This observation was not true for whole-body irradiated larvae. After local irradiation of the hemopoietic organs at the 4th instar premolting stage, the hemocyte densities were clearly reduced and the hemopoietic organ capacity was disrupted. The change in hemocyte densities was accompanied by changes of hemolymph components. These results show that radiosurgery utilizing heavy ion beams can destroy a specific organ or tissue in a living organism.

Animals↗