OPTN/SRTR 2011 Annual Data Report: Kidney Matas, A. J.; Smith, J. M.; Skeans, M. A. ...
American journal of transplantation,
January 2013, 2013-Jan, 2013-01-00, 20130101, Letnik:
13
Journal Article
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ABSTRACT A shortage of kidneys for transplant remains a major problem for patients with end‐stage renal disease. The number of candidates on the waiting list continues to increase each year, while ...organ donation numbers remain flat. Thus, transplant rates for adult wait‐listed candidates continue to decrease. However, pretransplant mortality rates also show a decreasing trend. Many kidneys recovered for transplant are discarded, and discard rates are increasing. Living donation rates have been essentially unchanged for the past decade, despite introduction of desensitization, non‐directed donations, and kidney paired donation programs. For both living and deceased donor recipients, early posttransplant results have shown ongoing improvement, driven by decreases in rates of graft failure and return to dialysis. Immunosuppressive drug use has changed little, except for the Food and Drug Administration approval of belatacept in 2011, the first approval of a maintenance immunosuppressive drug in more than a decade. Pediatric kidney transplant candidates receive priority under the Share 35 policy. The number of pediatric transplants peaked in 2005, and decreased to a low of 760 in 2011. Graft survival and short‐term renal function continue to improve for pediatric recipients. Posttransplant lymphoproliferative disorder is an important concern, occurring in about one‐third of pediatric recipients.
Kidney transplant and liver transplant are the treatments of choice for patients with end‐stage renal disease and end‐stage liver disease, respectively. Pancreas transplant is most commonly performed ...along with kidney transplant in diabetic end‐stage renal disease patients. Despite a steady increase in the numbers of kidney and liver transplants performed each year in the United States, a significant shortage of kidneys and livers available for transplant remains. Organ allocation is the process the Organ Procurement and Transplantation Network (OPTN) uses to determine which candidates are offered which deceased donor organs. OPTN is charged with ensuring the effectiveness, efficiency and equity of organ sharing in the national system of organ allocation. The policy has changed incrementally over time in efforts to optimize allocation to meet these often competing goals. This review describes the history, current status and future direction of policies regarding the allocation of abdominal organs for transplant, namely the kidney, liver and pancreas, in the United States.
This special article describes the history, current status, and future direction of policies regarding the allocation of kidneys, livers, and pancreata for transplant in the United States, reflecting efforts to optimize allocation to help ensure effectiveness, efficiency, and equity of organ sharing. Also see article by Colvin‐Adams et al on page 3213.
We analyze the effect of the antineutrino mass over the
β
−
-decay rates calculated within the scheme of the Gross Theory of Beta Decay (GTBD). We give a non-null value to the mass of the ...antineutrino participating in
β
−
-decay,
(
A
,
Z
)
→
(
A
,
Z
+
1
)
+
e
−
+
ν
̄
e
, which is usually neglected because we know it is small compared with electron mass. We have slightly modified the GTDB by inserting the antineutrino mass in the formalism. We have adopted a Gaussian energy distribution function with the axial-vector weak coupling constant
g
A
= 1, as well as a new set of the adjustable parameter
σ
N
related to the standard deviation for the Gamow-Teller resonance, updated experimental mass defects, and also an improved approximation for the Fermi function. Our sample consists of a set of 94 nuclei of interest in the pre-supernova phase, which have experimental data in terrestrial conditions available in the Letter of Nuclide. We have compared the calculation without the inclusion of the antineutrino mass with that adopting a really overestimated value of 50 keV for it to illustrate the effect on the decay rates. We have shown that they are improved only by approximately one per thousand in this case. We conclude that the effect of the antineutrino mass on decay rates is not relevant.
The beta decay and electron capture rates are of fundamental importance in the evolution of massive stars in a pre-supernova core. The beta decay process gives its contribution by emitting electrons ...in the plasma of the stellar core, thereby increasing pressure, which in turn increases the temperature. From the other side, the electron capture removes free electrons from the plasma of the star core contributing to the reduction of pressure and temperature. In this work we calculate the beta decay and electron capture rates in stellar conditions for 63 nuclei of relevance in the pre-supernova stage, employing Gross Theory as the nuclear model. We use the abundances calculated with the Saha equations in the hypothesis of nuclear statistical equilibrium to evaluate the time derivative of the fraction of electrons. Our results are compared with other evaluations available in the literature. They have shown to be one order less or equal than the calculated within other models. Our results indicate that these differences may influence the evolution of the star in the later stages of pre-supernova.
While neurodegeneration underlies the pathological basis for permanent disability in multiple sclerosis (MS), predictive biomarkers for progression are lacking. Using an animal model of chronic MS, ...we find that synaptic injury precedes neuronal loss and identify thinning of the inner plexiform layer (IPL) as an early feature of inflammatory demyelination—prior to symptom onset. As neuronal domains are anatomically segregated in the retina and can be monitored longitudinally, we hypothesize that thinning of the IPL could represent a biomarker for progression in MS. Leveraging our dataset with over 800 participants enrolled for more than 12 years, we find that IPL atrophy directly precedes progression and propose that synaptic loss is predictive of functional decline. Using a blood proteome-wide analysis, we demonstrate a strong correlation between demyelination, glial activation, and synapse loss independent of neuroaxonal injury. In summary, monitoring synaptic injury is a biologically relevant approach that reflects a potential driver of progression.
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•Synaptic injury is an early event associated with downstream demyelination in EAE•Accelerated retinal synaptic injury precedes disease progression in people with MS•Blood biomarkers of myelin injury and synaptic loss are independently associated
Cordano et al. demonstrate that atrophy of the IPL (constituted by connections between ganglion cells and deeper retinal layers) could function as a biologically relevant prognostic biomarker for relentlessly progressive disease. Their work also unravels a strong correlation between demyelination and synaptic loss using blood biomarkers in an independent cohort.
We evaluate the
β
-decay rates within the gross theory of beta decay (GTBD) and compare the results for different values of the axial-vector coupling constant,
g
A
= 0.76,
g
A
= 0.88,
g
A
= 1,
g
A
= ...1.13, and
g
A
= 1.26, and also different energy distribution functions like Gaussian, exponential, Lorentzian, and modified Lorentzian ones. We use new sets of parameters as well as updated experimental mass defects and also an improved approximation for the Fermi function. We compare our calculated results for a set of 94 nuclei of interest in pre-supernova phase, with experimental data in terrestrial conditions and also with other theoretical models like the QRPA, the shell model (SM), and different versions of the GTBD. We show that best results are obtained with
g
A
= 1 using Gaussian and Lorentzian distributions, being the rates for the 74 and 80% of our sample, respectively, of the same order of magnitude that of experimental data. Finally, we show that the present results within the GTBD are better than those within the QRPA model and also older versions of the GTBD for the isotopes of cobalt and iron families, and comparable with SM for some elements.
Donor pancreas utilization rates for whole organ transplant have remained low and have decreased over time. To identify the reasons for nonuse of pancreas from donors who meet common baseline ...acceptance criteria, we examined Organ Procurement and Transplantation Network data from 2005 to 2007 and identified a subgroup of 1763 "potential pancreas donors" defined by age (19-40 years), body mass index (<30 kg/m), successful liver donation, and negative viral serology testing, which were not used. We characterize this cohort of potential donors including reasons for refusal, factors that may contribute to pancreas acceptance and function, and potential explanations for the lack of growth in pancreas organ utilization.
The Plasmodium falciparum parasite is transmitted in its sexual gametocyte stage from man to mosquito and as asexual sporozoites from mosquito to man. Developing gametocytes sequester preferentially ...in the bone marrow, but mature stage gametocytes are released to the bloodstream. Sexual stage parasite surface proteins are of interest as candidate target antigens for transmission blocking vaccines.
In this study, the transcript profiles of rif and var genes, known to encode surface antigens in asexual blood stage parasites, were investigated at different stages of 3D7/NF54 gametocytogenesis and in sporozoites.
Gametocytes exhibited a rif transcript profile unlinked to the rif and var transcript profile of the asexual progenitors. At stage V, mature gametocytes produced high levels of a single rif gene, PF13_0006, which also dominated the rif transcript profile of sporozoites. All var genes appeared to be silenced in sporozoites.
The most prominent variant surface antigen transcribed in both gametocytes and sporozoites of 3D7/NF54 is a single variant of the RIFIN protein family. This discovery may lead to the identification of the parasites binding ligands responsible for the adhesion during sexual stages and potentially to novel vaccine candidates.
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