Unconventional resource development has been enabled by advanced completion methods such as horizontal drilling and multistage hydraulic fracturing. However, unconventional reservoir production rates ...decline more rapidly relative to conventional reservoirs, and recovery factors remain relatively low. Enhancing hydrocarbon recovery can be improved through a fundamental understanding of transport processes inside unconventional rocks. This work provides unique insights into fluid transport mechanisms in unconventional rocks during miscible displacement using a direct and noninvasive method to quantitatively detect hydrocarbons and their distribution inside rock samples by proton NMR imaging coupled with theoretical analysis of experimental results. This study shows the importance of unconventional rock morphology and pore structure to better understanding fluid transport and overall mass transfer rates. Different transport mechanisms in representative homogeneous and heterogeneous unconventional tight rocks are demonstrated. For homogeneous tight rocks, viscous or hydraulic flow is the dominant fluid transport mechanism in the direction of an applied pressure differential. However, a more complex behavior is observed in heterogeneous tight rocks. Despite smaller average pore sizes, the heterogeneous tight rocks can possess macroscopic permeabilities comparable to larger-pore rocks due to microfracture(s) in the sample that remain open at field relevant net confining stresses. Such microfractures enable a dual fluid transport mechanism inside the heterogeneous tight rock: hydraulic fluid transport along microfracture(s) and diffusion dominated fluid exchange across microfracture(s) inside the rock matrix. Overall mass transfer rates through heterogeneous tight rocks depends on the interplay of these two transport mechanisms, relative rates and travel distances. Experiments with lab cores showed that for fluid exchange of an injected fluid with the in situ fluid, diffusion in the matrix is a rate limiting step. More study is required to upscale our observations to a field relevant scale.
Static cold storage is the cheapest and easiest method and current gold standard to store and preserve donor organs. This study aimed to compare the preservative capacity of ...gluconate-lactobionate-dextran (Unisol) solutions to histidine-tryptophan-ketoglutarate (HTK) solution. Murine syngeneic heterotopic heart transplantations (Balb/c-Balb/c) were carried out after 18 h of static cold storage. Cardiac grafts were either flushed and stored with Unisol-based solutions with high-(UHK) and low-potassium (ULK) ± glutathione, or HTK. Cardiac grafts were assessed for rebeating and functionality, histomorphologic alterations, and cytokine expression. Unisol-based solutions demonstrated a faster rebeating time (UHK 56 s, UHK + Glut 44 s, ULK 45 s, ULK + Glut 47 s) compared to HTK (119.5 s) along with a better contractility early after reperfusion and at the endpoint on POD 3. Ischemic injury led to a significantly increased leukocyte recruitment, with similar degrees of tissue damage and inflammatory infiltrate in all groups, yet the number of apoptotic cells tended to be lower in ULK compared to HTK. In UHK- and ULK-treated animals, a trend toward decreased expression of proinflammatory markers was seen when compared to HTK. Unisol-based solutions showed an improved preservative capacity compared with the gold standard HTK early after cardiac transplantation. Supplemented glutathione did not further improve tissue-protective properties.
Summary
Between 2000 and 2014, five patients received bilateral hand (n = 3), bilateral forearm (n = 1), and unilateral hand (n = 1) transplants at the Innsbruck Medical University Hospital. We ...provide a comprehensive report of the long‐term results at 20 years. During the 6–20 years follow‐up, 43 rejection episodes were recorded in total. Of these, 27.9% were antibody‐related with serum donor‐specific alloantibodies (DSA) and skin‐infiltrating B‐cells. The cell phenotype in rejecting skin biopsies changed and C4d‐staining increased with time post‐transplantation. In the long‐term, a change in hand appearance was observed. The functional outcome was highly depending on the level of amputation. The number and severity of rejections did not correlate with hand function, but negatively impacted on the patients´ well‐being and quality of life. Patient satisfaction significantly correlated with upper limb function. One hand allograft eventually developed severe allograft vasculopathy and was amputated at 7 years. The patient later died due to progressive gastric cancer. The other four patients are currently rejection‐free with moderate levels of immunosuppression. Hand transplantation remains a therapeutic option for carefully selected patients. A stable immunologic situation with optimized and individually adopted immunosuppression favors good compliance and patient satisfaction and may prevent development of DSA.
Background
Several studies in solid organ transplantation have shown a correlation between donor and recipient sex mismatch and risk of graft loss. In this study, we aimed to analyze the impact of ...donor and recipient sex matching on patient and pancreas graft survival in a large single‐center cohort.
Methods
We retrospectively analyzed all first simultaneous pancreas‐kidney transplants performed between 1979 and 2017 at the Medical University of Innsbruck.
Results
Of 452 patients, 54.6% (247) received a sex‐matched transplant. Patient survival (P = .86), death‐censored pancreas graft survival (dcPGS, P = .26), and death‐censored kidney graft survival (dcKGS, P = .24) were similar between the sex‐matched and sex‐mismatched groups. Patient survival and dcPGS at 1, 5, and 15 years were 95.9%, 90.0%, and 62.1% and 86.1%, 77.1%, and 56.7% in the sex‐matched group and 93.6%, 86.2%, and 62.4% and 83.1%, 73.3%, and 54.3% in the sex‐mismatched group. Sex matching led to a lower odds of severe postoperative complications (41.2% vs 49.0%; OR 0.57, 95%CI 0.33‐0.97; P = .038); however, no increased odds of other adverse postoperative outcomes was detected.
Conclusion
Our study demonstrates that sex matching reduced the odds of postoperative complications but did not impact other early and late outcome parameters in our cohort.
In vascularized composite allotransplantation (VCA), invasive tissue biopsies remain the gold standard in diagnosing rejection carrying significant morbidity. We aimed to show feasibility of ...tape‐stripping for noninvasive immune monitoring in VCA. Tape‐stripping was performed on allografts and native skin of upper extremity transplant recipients. Healthy nontransplanted individuals served as controls. The technique was also used in swine on naïve skin in nontransplanted animals, native skin of treated, transplanted swine, nonrejecting VCAs, and rejecting VCAs. Extracted protein was analyzed for differences in cytokine expression using Luminex technology. Significantly decreased levels of INFγ and IL‐1Ra were seen between human allograft samples and native skin. In swine, rejecting grafts had increased IL‐1Ra compared to naïve and native skin, decreased levels of GM‐CSF compared to native skin, and decreased IL‐10 compared to nonrejecting grafts. Unsupervised hierarchical clustering revealed rejecting grafts separated from the nonrejecting (P = 0.021). Variable importance in projection scores identified GM‐CSF, IL‐1Ra, and IL‐2 as the most important profiles for group discrimination. Differences in cytokine expression are detectable in human VCA patient native skin and VCA graft skin using a noninvasive tape‐stripping method. Swine studies suggest that differences in cytokines between rejecting and nonrejecting grafts are discernable.
Contrairement au préjugé occidental d'un culte asocial pour ne pas dire libertaire, le bouddhisme dans ses différentes écoles fut en réalité fortement impliqué dans la vie sociale et politique des ...régions qu'il a traversées. Un autre cliché est de ne voir dans cette religion qu'une spiritualité, presque une hygiène de vie, faite de méditation dénuée de règles morales et juridiques. Cet ouvrage entend se dégager de telles idées reçues en présentant les sources des normes bouddhiques, celles qui régissent la communauté monacale bien sûr, mais aussi celles qui s'adressent aux laïcs, relatives à la famille, à la sexualité, au comportement personnel, au travail, à la propriété, au commerce, aux relations entre religion et politique. Il entend montrer que du Tibet au Japon en passant par la Chine, les écoles bouddhistes se sont inscrites dans des contextes culturels qu'elles ont influencés mais qui ont aussi été influencés par elles. Ces interactions entre religion et cultures se reflètent dans le miroir des normes, jusqu'à la rencontre avec la modernité occidentale, cause pour certains d'une déformation si ce n'est d'une dénaturation du message bouddhique originel. Mais l'origine n'est-elle pas toujours mythique ? Ceux qui cherchent à réhabiliter une tradition ne tombent-ils pas, sans le savoir, dans le travers qu'ils voudraient éviter : la reconstruction de normes qui leur paraissent plus adéquates, autrement dit mieux adaptées à leur situation actuelle ? Les auteurs ont tenté de faire reposer ces questions sur des recherches historiques, juridiques et sociologiques.
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