Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ORGANS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 181 records · Page 10Linked to original sources

Controlling the size of organs and organisms.

A key difference between yeast and metazoans is the need of the latter to regulate cell proliferation and growth to create organs (and organisms) of reproducible size and shape. Great progress has been made in understanding how growth, cell size and the cell cycle are controlled in metazoans. Recent work has shown that disruption of conserved components of the insulin and Tor kinase pathways can alter organ size, indicating that the normal functioning of these pathways is essential for organ size control. However, disruption of genes that regulate patterning and of genes that control cell adhesion and cell polarity has a much more dramatic effect on final organ size than does manipulation of the cell cycle or of basal growth control mechanisms. These data point to an 'organ-size checkpoint' that regulates cell division, cell growth and apoptosis. Recent data suggests that cell competition may play an important role in implementing the organ-size checkpoint.

Animal Structures↗

Removal of bulk dissolved organic carbon (DOC) and trace organic compounds by bank filtration and artificial recharge.

Bank filtration and artificial recharge provide an important drinking water source to the city of Berlin. Due to the practice of water recycling through a semi-closed urban water cycle, the introduction of effluent organic matter (EfOM) and persistent trace organic pollutants in the drinking water is of potential concern. In the work reported herein, the research objectives are to study the removal of bulk and trace organics at bank filtration and artificial recharge sites and to assess important factors of influence for the Berlin area. The monthly analytical program is comprised of dissolved organic carbon (DOC), UV absorbance (UVA254), liquid chromatography with organic carbon detection (LC-OCD), differentiated adsorbable organic halogens (AOX) and single organic compound analysis of a few model compounds. More than 1 year of monitoring was conducted on observation wells located along the flowpaths of the infiltrating water at two field sites that have different characteristics regarding redox conditions, travel time, and travel distance. Two transects are highlighted: one associated with a bank filtration site dominated by anoxic/anaerobic conditions with a travel time of up to 4-5 months, and another with an artificial recharge site dominated by aerobic conditions with a travel time of up to 50 days. It was found that redox conditions and travel time significantly influence the DOC degradation kinetics and the efficiency of AOX and trace compound removal.

Berlin↗

Do patients want to talk to their physicians about organ donation? Attitudes and knowledge about organ donation: a study of Orange County, California residents.

This study surveyed Orange County, California residents to determine their attitudes and knowledge about organ donation and in particular to determine what factors influence the decision to donate one's organs upon death. Respondents were recruited from the Orange County Superior Court jury pool (N = 378). Each completed a 44 item questionnaire. Findings from the analysis of Questionnaire Data reveal that nearly three-quarters of respondents had considered donating their organs, yet less than one-third had made arrangements to donate. Having an accurate knowledge about organ donation and being willing to accept a donated organ were particularly robust factors associated with the likelihood to donate. Having spoken with a physician was also a positive factor, yet just 5% of the sample had done so, and two-thirds of respondents did not want to discuss organ donation with their physician. The study's findings suggest that enhanced recruitment may be achieved by focusing on education (especially increased emphasis on the family's role) and by targeting both parents and their children. Finally, although physicians are encouraged to discuss organ donation with patients, more information is needed to explain why patients may not want to talk about this topic with their doctors.

Adult↗

Protection capacity against low-density lipoprotein oxidation and antioxidant potential of some organic and non-organic wines.

Current research suggests that phenolics from wine may play a positive role against oxidation of low-density lipoprotein (LDL), which is a key step in the development of atherosclerosis. Considering the effects of different wine-making techniques on phenols and the wine consumption preference influencing the benefical effects of the product, organically and non-organically produced wines were obtained from the grapes of Vitis vinifera origin var: Carignan, Cabernet Sauvignon, Merlot, Grenache, Columbard and Semillon. Levels of total phenols [mg/l gallic acid equivalents (GAE)], antioxidant activity (%) and inhibition of LDL oxidation [%, inhibition of diene and malondialdehyde (MDA) formation] were determined. Some phenolic acids (gallic acid, p-hydroxybenzoic acid, syringic acid, 2,3-dihydroxybenzoic acid, ferulic acid, p-coumaric acid and vanillic acid) were quantified by high-performance liquid chromatography equipped with an electrochemical detection carried at +0.65 V (versus Ag/AgCl, 0.5 microA full scale). The highest concentrations of gallic, syringic and ferulic acids were found in organic Cabernet Sauvignon; 2,3-dihydroxybenzoic acid in organic Carignan and p-coumaric and vanillic acids in non-organic Merlot wine. High levels of antioxidant activity (AOA), inhibition of LDL oxidation and total phenol levels were found in non-organic Merlot (101.950% AOA; 88.570% LDL-diene; 41.000% LDL-MDA; 4700.000 mg/l GAE total phenol) and non-organic Cabernet Sauvignon (92.420% AOA; 91.430% LDL-diene; 67.000% LDL-MDA; 3500.000 mg/l GAE total phenol) grape varieties. Concentrations of some individual phenolic constituents (ferulic, p-coumaric, vanillic) are correlated with high antioxidant activity and inhibition of LDL oxidation. The best r value for all examined characteristics was determined for gallic acid, followed by 2,3-dihydroxybenzoic, syringic, ferulic and p-coumaric acids. Negative correlation of vanillic with MDA and p-hydroxybenzoic acid with LDL were confirmed by principal component analysis (PCA) analyses. Red wines display a higher antioxidant activity (81.110% AOA) than white ones (19.512% AOA). The average level of LDL inhibition capacity in red wine was determined as 87.072% and for the white as 54.867%.

Antioxidants↗

Organ procurement and renal transplants in Spain: the impact of transplant coordination. Spanish National Transplant Organization (ONT)

The growing shortage of cadaveric organ donors remains the major obstacle to achieve satisfactory rates of transplantation. In Spain an integrated transplant organization programme, mainly focusing on organ procurement, has been established, based on a network of well-trained transplant coordinators. In every hospital that was a potential candidate for donor procurement, a transplant coordinating team was founded, including medical doctors and nurses (42% of whom belonged to renal units). The team was put in charge of all steps of transplant procurement, from locating potential donors to the organ grafting or tissue banking. The teams were integrated into a National Organization of Transplants (ONT), i.e. a coordinating structure without executive function. The annual rate of cadaveric organ donors increased from 14.3 per million population (p.m.p.) in 1989 to 21.7 donors p.m.p. in 1992. Total solid organ retrieval rate increased by 81% and renal transplants by 44% during the same period (from 1039 to 1492, i.e. from 26 to 38.8 renal transplants per million population, 99% of which were kidneys from cadaveric donors). This successful approach has overcome obstacles such as untrained or undertrained staff, failure to identify donors, or reluctance to approach grieving families.

Humans↗

Strategies for success among OPOs: a study of three organ procurement organizations.

Productivity among organ procurement organizations varies widely in the US, and the pressure to determine critical success factors increases as the organ pool shrinks and managed care expands. This study compared three successful organ procurement organizations, identified commonalities among them in cost of doing business, and examined direct and indirect expenses, staffing, specialized requestor programs, and professional and public education programs. The three organ procurement organizations were chosen because of their performance in terms of donors per million population, complexity, and size. The following key indicators were compared and analyzed: annual operating budget, size and composition of staff, funds and resources invested in professional education versus public education, tissue recovery operations, results of minority initiatives, and employee compensation programs.

Budgets↗

Model organ description protocols for completion by transplant surgeons using organs procured from medical examiner cases.

A significant number of donor organs emanate from the medical examiner's or coroner's offices, because victims of head injuries from vehicular accidents, falls, assaults, gunshot injuries, and unattended cerebrovascular accidents fall under the jurisdiction of the medical examiner or coroner. Unfortunately, many organ procurement organizations may not fully understand the legal responsibilities of the medical examiner. Most of the medical examiner or coroner cases could be used without compromising the medical-legal responsibilities of the medical examiner or coroner if a reliable description of the respective organ could be made after surgical removal by either having a pathologist present or by having the surgeon prepare a description of the respective organ. The objective of this paper is to present a series of protocols that have been designed to describe the heart, lungs, liver, kidney, and spleen for use by organ transplant surgeons. These protocols have proven to be highly successful in making more organs available for transplantation.

Autopsy↗

A potential link between the turnover of soil organic matter and the release of aged organic contaminants.

Soil column experiments were conducted to investigate the release of aged organic contaminants (adsorbable organohalogens, [AOX]) and the potential effects of microbial turnover of soil organic matter onto the contaminant release from two different soils of former wastewater infiltration sites. Under reference conditions, the total carbon flux ranged from 6 to 9 mg/kg/d from the two soils. More than 92% of it was due to mineralization (CO2) and below 8% to the dissolved organic carbon (DOC) in the column effluent. Despite very different organohalogen levels in the two soils, the fluxes of AOX were similar (1 microg/kg/d). Microbial activity was altered by changing temperature and the solution pH and by drying. In all experiments where increased microbial respiration (CO2 production) was observed, the release of organic contaminants in the column effluent also increased. Fluxes of nickel, zinc, and phosphate showed a completely different pattern, suggesting that their retention in soil is determined by chemical parameters. A linear correlation analysis provided clear evidence that AOX and DOC fluxes are closely linked to each other. However, the superimposition of abiotic and biotic processes in the soils did not allow a causal relation to be established between the mineralization of soil organic matter and the release of organic contaminants sequestered in the soil. Our findings suggest that microbial activity may have a significant impact on the extent to which contaminated soils may act as a source of persistent organic pollutants.

Bacteria↗

Social and utilitarian considerations for allocating organs within a national organ sharing system: a computerized simulation model for policy decision-making.

BACKGROUND: An organ-sharing system should achieve fairness and optimal graft longevity. Balancing between social and utilitarian considerations is a sensitive ethical, public and medical issue that requires a means to examine the consequences of any allocation policy or planned changes thereof. OBJECTIVE: To evaluate the performance and applicability of a computerized simulation model by examining the impact of two opposing organ allocation policies (social or utilitarian) on predicted organ distribution regarding age, waiting time, recipient sensitization measured by panel reactive antibody level, and overall donor-recipient tissue matching (measured by the number of HLA antigen mismatches). METHODS: Using a computerized simulation model, virtual donors and recipients were emulated and organs were allocated according to either social algorithms or utilitarian policies. The resulting number of HLA mismatches, PRA, age, and waiting time distributions were compared between allocation strategies. RESULTS: Simulating allocation of 7,000 organs to 17,000 candidate recipients and implementing social policies yielded donor-recipient compatibility comparable to utilitarian policies (0-1 mm: 19.4% vs. 28%) while allocating 66.7% of organs to long waiters (>48 months). CONCLUSION: This computerized simulation model is a valuable tool for decision-makers establishing or modifying organ allocation policies.

Age Factors↗

Medicare and Medicaid programs; conditions for coverage for organ procurement organizations (OPOs). Final rule.

This rule finalizes the February 4, 2005 proposed rule entitled "Medicare and Medicaid Programs; Conditions for Coverage for Organ Procurement Organizations (OPOs)." It establishes new conditions for coverage for organ procurement organizations (OPOs) that include multiple new outcome and process performance measures based on organ donor potential and other related factors in each service area of qualified OPOs. Our goal is to improve OPO performance and increase organ donation. In addition, this final rule re-certifies these 58 OPOs from August 1, 2006 through July 31, 2010 and provides an opportunity for them to sign agreements with the Secretary that will begin on August 1, 2006 and end on January 31, 2011. New agreements are needed so that the Medicare and Medicaid Programs can continue to pay them for their organ procurement activities after July 31, 2006.

Humans↗

[Multiple organ failure syndrome: correlation of mortality and the Modified Criteria for Multiple Organ Failure].

Seventy-two patients from one month to 15 years of age that according with the Modificated criterion of multiple organ failure (MCMOF) had two or more organ failures were studied. They were divided into two groups: Group I consisted of 55 patients that survived and group II of 17 patients that died. In both groups, the MCMOF was determinated upon admission and discharge, as well as the maximum obtained during the evolution. The comparison of both groups, with respect to the number of organic failures presented and the points of MCMOF showed highly significant differences with p less than 0.001, found in group I: 1.27 +/- 0.96 organ failures and a value of 4.84 +/- 2.92 of the MCMOF and in the group II: 3.84 +/- 1.59 organ failures and 25.68 +/- 7.57 points of the MCMOF respectively. The comparison between the number of organic failures at admission and discharge showed significant differences in both groups, having the tendency to decrease in group I from 1.87 +/- 1.01 to 0.56 +/- 0.60 and in the group II to increase from 3.41 +/- 1.46 to 4.35 +/- 1.45. The same phenomenon was observed for the values of the MCMOF with a qualification of 7.72 +/- 5.36 to 1.87 +/- 1.82 in a group I and from 18.94 +/- 10.31 to 33.38 +/- 8.27 in group II. Spearman correlation coeficient between the number of organic failures and values of the MCMOF showed and r = 0.99 and equivalent p less than 0.001, highly significant.

Adolescent↗

Surface ultrastructure of pit organ, spectacle, and non pit organ epidermis of infrared imaging boid snakes: A scanning probe and scanning electron microscopy study.

Boid snakes possess unique infrared imaging pit organs. The ultrastructure of the surfaces of these organs scatter or reflect electromagnetic radiation of specific wavelengths. Pit organ epidermal surfaces of boid snakes are covered with arrays of pore-like structures called micropits. In order to determine the dimensions of this complicated surface structure, we have performed the first ultrastructural analysis on snake epidermis by high-resolution microscopy techniques. Using scanning probe microscopy and scanning electron microscopy, we found that the epidermis of pit organ, maxillary non pit organ, spectacle, and ventral scales contain arrays of micropits. These scale surfaces also contain major surface features of overlapping plate-like structures. Pit organ micropits averaged 319 nm in diameter and 46 nm in depth and were spaced an average of 808 nm from each other. These micropits were significantly deeper, of greater diameter, and spaced at greater distances apart than those of the other scales. Plate structures of the pit organs had a mean distance between plates of 3.5 microm and a mean plate step height of 151 nm. These differences serve to strengthen the argument that arrays of micropit and plate surface structures function as spectral filters or anti-reflective coatings with respect to incident electromagnetic radiation.

Animals↗

Xenografted human whole embryonic and fetal entoblastic organs develop and become functional adult-like micro-organs.

BACKGROUND AND AIMS: The aim of this study was to study the morphological and functional development in vivo of whole human embryonic and fetal stomachs, intestines, tracheas, and lungs, which would otherwise be ethically and technically impossible to perform in utero, by microsurgically grafting these organs into nude mice. MATERIALS AND METHODS: Five hundred fifty-seven human organs obtained from legally aborted embryos and fetuses of 6-10 weeks were microsurgically grafted into nude mice for 1 to 273 days. Following different grafting times, biopsies were taken for optical and electron microscopy, in situ hybridization, and cellular kinetics studies. A catheter was introduced into the human organs in order to collect and analyze secretions. RESULTS: All of the grafts took successfully. Macroscopic growth was fast during the first 6 to 10 weeks, following which organ size was stable. In situ hybridization studies detected only a minute level of mouse mesenchymal chimerism in the grafts. The different epithelial cells differentiated, became of adult type, and remained normal during the remainder of the grafting periods. The pH of gastric juice from stomachs grafted for 10 to over 90 days dropped from 8.0 +/- 0.1 to 1.58 +/- 0.29 over this time period (P < 0.001), intrinsic factor levels were stable, and pepsin ranged from 6.8 +/- 7.8 to 134 +/- 51 units (P < 0.001). CONCLUSIONS: These results demonstrate that the development of entoblastic organs from human embryos and fetuses microsurgically grafted into nude mice is similar to that occurring in utero. As such, this method provides a model for the analysis of whole human organs in development and later normal adult-like micro-organs for physiological, therapeutic, and pathological studies.

Animals↗

The ultrastructural basis of steroid production in the Y-organ and the mandibular organ of the crabs Hemigrapsus nudus (Dana) and Carcinus maenas L.

The ultrastructure of the steroid producing Y-organ and the mandibular organ of the crustaceans Hemigrapsus nudus and Carcinus maenas has been studied with reference to the well investigated steroid secreting cells (SSC) of mammals. In accordance with the most important characteristic of mammalian SSC, abundant SER could be shown in the Y-organ, where it is unevenly distributed. The amount of SER seems to vary in correlation with the secretion of moulting hormone during the moult cycle. Most Y-organ cells contain a great number of mitochondria of the tubular type, another important characteristic of mammalian SSC. The ultrastructure of the mandibular organ of C. maenas differs considerably from that of the Y-organ. Some SER was found, mitochondria of unusual shape and size were conspicuous. No definite conclusion as to the function of the mandibular organ is yet to be drawn.

Animals↗

Relationships between study organization, retrieval organization, and general and strategy-specific memory knowledge in young children.

The present study examined relationships between young children's memory knowledge and their use of taxonomic and color memory organization. Forty-eight 5-, 6-, and 7-year-olds were administered metamemory tests of organization-strategy knowledge and general memory knowledge, and were tested on two study-recall tasks before, and two study-recall tasks after, training in the use of color or taxonomic organization. Study organization (grouping) scores were low before training, but improved significantly in post-training tasks. Training effects were less pronounced for retrieval organization (clustering) and did not occur for item recall. Relationships between taxonomic study and retrieval organization were apparent only for the 7-year-olds, while relationships between color organization at study and retrieval were not apparent at any age level. Relationships between metamemory, strategy-use, and recall proficiency were evident on some tasks for 7-year-olds, but not for younger children. Although teacher ratings of the children's mastery orientations were also found to be related to recall proficiency for the older subjects, specific strategy knowledge was a more consistent correlate of strategy use and amount recalled.

Child↗

The families of children who fail to thrive: preliminary investigations of parental deprivation among organic and non-organic cases.

A majority of cases of failure to thrive (FTT) do not have a known organic etiology. Social and psychological determinants are sought for these "non-organic failure to thrive" (N-O FTT) cases. Social and psychological differences between non-organic and organic cases are also explored here. With the introduction of the term, "maternal deprivation," medical practitioners have implicated mothers' deficiencies as instrumental in the etiology of N-O FTT. However, these mothers are themselves usually deprived. Lack of cooperation in childcare by both parents is noted when classic clinical cases are reviewed. We suggest that the concept, "parental deprivation," provides a more accurate model. Preliminary research findings support our hypothesis that mothers of FTT infants do not have good social support networks. Teen motherhood and socioeconomic status also appear to be important, but not necessary as determinants. An unexpected finding is that there are few differences in the social deficiencies of families of N-O FTT infants as compared to those failing for organic reasons. Two unanticipated findings appear noteworthy. First, infants failing for organic reasons are significantly smaller and thinner at birth, independent of pregnancy complications or prematurity. Second, infants failing for non-organic reasons are more likely to present during the period of infant-caretaker role development and less likely in the later toddler stage. Additional research into the feasibility of strengthening family supports as a basis of intervention is recommended.

Adolescent↗

DNA analysis of intracellular Campylobacter-like organisms associated with the porcine proliferative enteropathies: novel organism proposed.

Intracellular Campylobacter-like organisms are a consistent feature of the porcine proliferative enteropathies. The relationship between these organisms and known Campylobacter sp. previously associated with the disease was studied using restriction enzyme analysis and DNA-DNA blot hybridization techniques. BglII restriction enzyme fragment patterns of DNA of the Campylobacter-like organisms were fundamentally different from those of C. mucosalis, C. hyointestnalis, C. jejuni, and C. coli. Crude DNA preparations from Campylobacter-like organisms hybridized strongly with homologous preparations, weakly with porcine DNA and not at all with DNA from Campylobacter sp. Fragment specific DNA probes prepared from Campylobacter-like organisms only hybridized with homologous preparations. This work suggests that the intracellular Campylobacter-like organisms are not one of the known Campylobacter sp. It is possible that they are a novel, uncultured organism worthy of a new name, such as HC. intracellulare'.

Animals↗

A novel in vitro system, the integrated discrete multiple organ cell culture (IdMOC) system, for the evaluation of human drug toxicity: comparative cytotoxicity of tamoxifen towards normal human cells from five major organs and MCF-7 adenocarcinoma breast cancer cells.

In vitro assays involving primary cells are used routinely to evaluate organ-specific toxic effects, for instance, the use of primary hepatocytes to evaluate hepatotoxicity. A major drawback of an in vitro system is the lack of multiple organ interactions as observed in a whole organism. A novel cell culture system, the integrated discrete multiorgan cell culture system (IdMOC), is described here. The IdMOC is based on the "wells within a well" concept, consisting of a cell culture plate with larger, containing wells, within each of which are multiple smaller wells. Cells from multiple organs can be cultured initially in the small wells (one organ per well, each in its specialized medium). On the day of toxicity testing, a volume of drug-containing medium is added to the containing well to flood all inner wells, thereby interconnecting all the small wells. After testing, the overlying medium is removed and each cell type is evaluated for toxicity using appropriate endpoints. We report here the application of IdMOC in the evaluation of the cytotoxicity of tamoxifen, an anticancer agent with known human toxicity, on primary cells from multiple human organs: liver (hepatocytes), kidney (kidney cortical cells), lung (small airway epithelial cells), central nervous system (astrocytes), blood vessels (aortic endothelial cells) as well as the MCF-7 human breast adenocarcinoma cells. IdMOC produced results that can be used for the quantitative evaluation of its anticancer effects (i.e., cytotoxicity towards MCF-7 cells) versus its toxicity toward normal organs (i.e., liver, kidney, lung, CNS, blood vessels).

Adenocarcinoma↗