Agroclimatic Evolution web application as a powerful solution for managing climate data.

Applying the AgroClimatic Evolution web application allows inquiries being made, data being collected and variables being calculated with the data acquired from different public agrometeorological stations on a single platform. Today all these stations from Murcia and Andalusia (Spain) are included, and stations elsewhere in Spain are being incorporated. This web application also offers the possibility of including each user's own stations, which increases the number and availability of data close to each farmer's plots. The data collected from stations is employed to collect daily data about weather and times, which are used to calculate the reference evapotranspiration (ETo). All the data are saved in a cloud database to later consult them and study their evolution. The data provided by all the stations are validated by applying the filters indicated in Standard UNE 500540:2004 "Automatic weather stations networks" by eliminating mistaken data that could alter correct ETo calculations. With the filtered data, and having calculated ETo, the user is provided with a comparison made with the raw data supplied by public stations. The main objective of this tool is to optimize the use of water resources available from data acquisition. Managing these data will contribute to make agriculture more sustainable and compatible with the natural environment.

Development of an Algorithm for an Automatic Determination of the Soil Field Capacity Using of a Portable Weighing Lysimeter.

The challenge today is to optimize agriculture water consumption and minimize leaching of pollutants in agro-ecosystems in order to ensure a sustainable agriculture. The use of different technologies and the adoption of different irrigation strategies can facilitate efficient fertigation management. In this respect, the determination of soil field capacity point is of utmost importance. The use of a portable weighing lysimeter allows an accurate quantification of crop water consumption and water leaching, as well as the detection of soil field capacity point. In this work, a novel algorithm is developed to obtain the soil field capacity point, in order to give autonomy and objectivity to efficient irrigation management using a portable weighing lysimeter. The development was tested in field grown horticultural crops and proved to be useful for optimizing irrigation management.

Prototype System for Measuring and Analyzing Movements of the Upper Limb for the Detection of Occupational Hazards.

In the work environment, there are usually different pathologies that are related to Repetitive Efforts and Movements (REM) that tend to predominantly affect the upper limbs. To determine whether a worker is at risk of suffering some type of pathology, observation techniques are usually used by qualified technical personnel. In order to define from quantitative data if there is a risk of suffering a pathology due to movements and repetitive efforts in the upper limb, a prototype of a movement measurement system has been designed and manufactured. This system interferes minimally with the activity studied, maintaining a reduced cost of manufacture and use. The system allows the study of the movements made by the subject in the work environment by determining the origin of the Musculoskeletal Disorder (MSD) from the movements of the elbow and wrist, collecting data on the position and accelerations of the arm, forearm and hand, and taking into account the risk factors established for suffering from an MSD: high repetition of movements, the use of a high force in a repetitive manner, or the adoption of forced positions. The data obtained with this system can be analyzed by qualified personnel from tables, graphs, and 3D animations at the time of execution, or stored for later analysis.

An agent-based approach for the application of nature's forms to product conceptual design.

Given current high market competitiveness, it is necessary to differentiate between products that perform the same function. For this objective, designer can recur to various sources of inspiration in the searching of the more attractive form during the conceptual design stage. One of these sources can be nature, which offers a large number of geometries and textures that can be used from a shape point of view to help the designer in the creative process. This work presents an agent-based approach for a design-aided tool to provide users with some ideas, beginning with simple parts/concepts, and then increasing the complexity level according to the answers offered by designer. The proposed paradigm was implemented using the JADE agent-based platform. In order to validate the platform, several product categories were offered to fifteen different users and a total of sixty design proposals were obtained with the aid of the platform. After evaluating all the proposals, twelve of the sixty designs were finally selected and modelled by a Computer-Aided Design software. The obtained results demonstrate the feasibility of using an agent-based approach to obtain an adaptive intelligent solution to the product conceptual design problem.

Peripheral Vascular Disease and Death in Southern European Kidney Transplant Candidates: A Competing Risk Modeling Approach.

BACKGROUND: The association between peripheral vascular disease (PVD) and survival among kidney transplant (KT) candidates is uncertain. METHODS: We assessed 3851 adult KT candidates from the Andalusian Registry between 1984 and 2012. Whereas 1975 patients received a KT and were censored, 1876 were on the waiting list at any time. Overall median waitlist time was 21.2 months (interquartile range, 11-37.4). We assessed the association between PVD and mortality in waitlisted patients using a multivariate Cox regression model, with a competing risk approach as a sensitivity analysis. RESULTS: Peripheral vascular disease existed in 308 KT candidates at waitlist entry. The prevalence of PVD among nondiabetic and diabetic patients was 4.5% and 25.3% (P < 0.0001). All-cause mortality was higher in candidates with PVD (45% vs 21%; P < 0.0001). Among patients on the waiting list (n = 1876) who died (n = 446; 24%), 272 (61%) died within 2 years after listing. Cumulative incidence of all-cause mortality at 2 years in patients with and without PVD was 23% and 6.4%, respectively (P < 0.0001); similar differences were observed in patients with and without diabetes. By competing risk models, PVD was associated with a 1.9-fold increased risk of mortality (95% confidence interval [95% CI], 1.4-2.5). This association was stronger in waitlisted patients without cardiac disease (subhazard ratio, 2.2; 95% CI, 1.6-3.1) versus those with cardiac disorders (subhazard ratio, 1.5; 95% CI, 0.9-2.5). No other significant interactions were observed. Similar results were seen after excluding diabetics. CONCLUSIONS: Peripheral vascular disease is a strong predictor of mortality in KT candidates. Identification of PVD at list entry may contribute to optimize targeted therapeutic interventions and help prioritize high-risk KT candidates.

Immune response and histology of humoral rejection in kidney transplantation / Respuesta inmune e histología de rechazo humoral en el trasplante renal

The adaptive immune response forms the basis of allograft rejection. Its weapons are direct cellular cytotoxicity, identified from the beginning of organ transplantation, and/or antibodies, limited to hyperacute rejection by preformed antibodies and not as an allogenic response. This resulted in allogenic response being thought for decades to have just a cellular origin. But the experimental studies by Gorer demonstrating tissue damage in allografts due to antibodies secreted by B lymphocytes activated against polymorphic molecules were disregarded. The special coexistence of binding and unbinding between antibodies and antigens of the endothelial cell membranes has been the cause of the delay in demonstrating the humoral allogenic response. The endothelium, the target tissue of antibodies, has a high turnover, and antigen-antibody binding is non-covalent. If endothelial cells are attacked by the humoral response, immunoglobulins are rapidly removed from their surface by shedding and/or internalization, as well as degrading the components of the complement system by the action of MCP, DAF and CD59. Thus, the presence of complement proteins in the membrane of endothelial cells is transient. In fact, the acute form of antibody-mediated rejection was not demonstrated until C4d complement fragment deposition was identified, which is the only component that binds covalently to endothelial cells. This review examines the relationship between humoral immune response and the types of acute and chronic histological lesion shown on biopsy of the transplanted organ (AU)

La respuesta inmune adaptativa constituye la base del rechazo del aloinjerto. Sus armas lesivas son la citotoxicidad celular directa o los anticuerpos. La primera, identificada desde los inicios del trasplante de órganos y la segunda, limitada al rechazo hiperagudo por anticuerpos preformados y no como respuesta alogénica. Ello permitió mantener durante décadas que la respuesta alogénica tenía solo un origen celular. Pero se ignoraron los trabajos experimentales de Gorer que demostraban daño tisular en aloinjertos por anticuerpos secretados por linfocitos B activados frente a moléculas polimórficas. La especial convivencia de unión y desunión entre anticuerpos y antígenos de membrana de células endoteliales ha sido la causa que retrasó la demostración de la respuesta alogénica humoral. El endotelio, que es el tejido diana de los anticuerpos, tiene un turnover alto y la unión antígeno-anticuerpo no es covalente. Si las células endoteliales sufren el ataque de la respuesta humoral, eliminan rápidamente de su superficie las inmunoglobulinas mediante shedding o internalización y, a la vez, degradan los componentes del complemento por la acción de MCP, DAF y CD59. Así, la presencia de las proteínas del complemento en la membrana de las células endoteliales es pasajera. De hecho, la forma aguda de rechazo por anticuerpos no se demostró hasta identificar el depósito del fragmento C4d del complemento, que es el único de unión covalente a las células endoteliales. Esta revisión analiza la relación entre la respuesta inmune humoral y los tipos de lesión histológica aguda y crónica de la biopsia del órgano trasplantado (AU)

Immune response and histology of humoral rejection in kidney transplantation.

The adaptive immune response forms the basis of allograft rejection. Its weapons are direct cellular cytotoxicity, identified from the beginning of organ transplantation, and/or antibodies, limited to hyperacute rejection by preformed antibodies and not as an allogenic response. This resulted in allogenic response being thought for decades to have just a cellular origin. But the experimental studies by Gorer demonstrating tissue damage in allografts due to antibodies secreted by B lymphocytes activated against polymorphic molecules were disregarded. The special coexistence of binding and unbinding between antibodies and antigens of the endothelial cell membranes has been the cause of the delay in demonstrating the humoral allogenic response. The endothelium, the target tissue of antibodies, has a high turnover, and antigen-antibody binding is non-covalent. If endothelial cells are attacked by the humoral response, immunoglobulins are rapidly removed from their surface by shedding and/or internalization, as well as degrading the components of the complement system by the action of MCP, DAF and CD59. Thus, the presence of complement proteins in the membrane of endothelial cells is transient. In fact, the acute form of antibody-mediated rejection was not demonstrated until C4d complement fragment deposition was identified, which is the only component that binds covalently to endothelial cells. This review examines the relationship between humoral immune response and the types of acute and chronic histological lesion shown on biopsy of the transplanted organ.

Medium-Term Renal Function in a Large Cohort of Stable Kidney Transplant Recipients Converted From Twice-Daily to Once-Daily Tacrolimus.

BACKGROUND: There is some evidence pointing toward better renal function in kidney transplant recipients (KTR) treated with once-daily tacrolimus (QD-TAC) vs. twice-daily tacrolimus (BID-TAC). METHODS: This is an extension study of a 1-year, single arm prospective study of stable KTR who were converted from BID-TAC to QD-TAC (4.9 ± 4.0 years after transplantation) in Spanish routine clinical practice. Patient and graft survival, renal function, acute rejection episodes, and other analytic parameters were assessed at 24 and 36 months after conversion. RESULTS: A total of 1798 KTR were included in the extension study. Tacrolimus doses at 36 months were significantly lower compared to those at time of conversion (-0.2 mg/day; P = 0.023). Blood levels were lower than baseline during all the study (P < 0.001). Graft and patient survival at 3 years after conversion were 93.9% and 95.1%, respectively. Compared with baseline, the mean estimated glomerular filtration rate (eGFR) remained very stable at all timepoints (56.7 ± 19.8 vs 58.1 ± 24.6 mL/min per 1.73 m(2) at month 36; P = 0.623). Even when patients reinitiating dialysis were counted as eGFR = 0, the mean eGFR was very stable. In fact, a small but significant increase was observed at 36 months versus baseline (+0.1 mL/min per 1.73 m(2); P = 0.025). An increase in proteinuria was observed at 36 months versus baseline (+0.11 g/24 h; P < 0.001). Acute rejection rates were low during the study. CONCLUSIONS: Conversion from BID-TAC to QD-TAC in a large cohort of stable KTR was safe and associated with a very stable renal function after 3 years. Comparative studies are warranted to assess the feasibility of such conversion.

Impact of immunosuppression treatment on the improvement in graft survival after deceased donor renal transplantation: a long-term cohort study

We analyzed graft half-life and attrition rates in 1045 adult deceased donor kidney transplants from 1986-2001, with follow-up to 2011, grouped in two periods (1986-95 vs. 1996-01) according to immunosuppression. The Kaplan-Meier curve showed a significant increase in graft survival during 1996-2001. The uncensored real graft half-life was 10.25 years in 1986-95 and the actuarial was 14.58 years in 1996-2001 (P<0.001). The attrition rates showed a significantly greater graft loss in 1986-95, even excluding the first year from the analysis. The decline in renal function was significantly less pronounced in 1996-2001, indicating better preservation of renal function, despite the increase in donor age and stroke as the cause of donor death. The parsimonious Cox multivariate model showed donor age, acute rejection, panel reactive antibody, cold ischemia time and delayed graft function were significantly associated with a higher risk of graft loss. In contrast, the risk of graft loss fell by 21% in 1996-2001 compared with 1986-95. A similar reduction (25%) was observed when MMF treatment was entered into the multivariate model instead of study period. Long-term graft survival improved significantly in 1996-2001 compared to 1986-1995 despite older donor age. Modern immunosuppression could have contributed to the improved kidney transplant outcome (AU)

Análisis de la vida media del injerto y de su tasa de pérdida en 1045 transplantes de donantes cadáver adultos entre 1986 y 2001, con seguimiento hasta 2011, clasificados en dos periodos en función de la inmunosupresión: 1986-1995 y 1996-2001. La curva de Kaplan-Meier mostró un aumento significativo de la supervivencia del injerto durante el periodo 1996-2001. La vida media real no censurada del injerto fue de 10,25 años en 1986-1995 y la actuarial fue de 14,58 años en 1996-2001 (p < 0,001). La tasa de pérdida del injerto fue significativamente mayor en 1986-1995, incluso con la exclusión del primer año del análisis. En 1996-2001, la disminución de la función renal fue menos pronunciada, observándose una mejor conservación a pesar de que los donantes tenían más edad y de que habían fallecido por accidente cardiovascular. El modelo parsimonioso multivariante de Cox reveló que la edad del donante, el rechazo agudo, el panel de anticuerpos reactivos, el tiempo de isquemia fría y la función retrasada del injerto se asociaban de forma significativa a un mayor riesgo de pérdida del injerto. Sin embargo, el riesgo de pérdida del injerto se vio reducido en un 21% en 1996-2001 en comparación con el periodo 1986-1995. Se observó una reducción similar (25%) al incluir el tratamiento con MMF en el modelo multivariante en lugar del periodo de estudio. La supervivencia del injerto a largo plazo mejoró significativamente en 1996-2001 frente al periodo 1986-1995, a pesar de que los donantes tenían más edad. Por lo tanto, la inmunosupresión moderna podría haber contribuido a la mejora de los resultados del transplante renal (AU)

Impact of immunosuppression treatment on the improvement in graft survival after deceased donor renal transplantation: a long-term cohort study.

We analyzed graft half-life and attrition rates in 1045 adult deceased donor kidney transplants from 1986-2001, with follow-up to 2011, grouped in two periods (1986-95 vs. 1996-01) according to immunosuppression. The Kaplan-Meier curve showed a significant increase in graft survival during 1996-2001. The uncensored real graft half-life was 10.25 years in 1986-95 and the actuarial was 14.58 years in 1996-2001 (P<0.001). The attrition rates showed a significantly greater graft loss in 1986-95, even excluding the first year from the analysis. The decline in renal function was significantly less pronounced in 1996-2001, indicating better preservation of renal function, despite the increase in donor age and stroke as the cause of donor death. The parsimonious Cox multivariate model showed donor age, acute rejection, panel reactive antibody, cold ischemia time and delayed graft function were significantly associated with a higher risk of graft loss. In contrast, the risk of graft loss fell by 21% in 1996-2001 compared with 1986-95. A similar reduction (25%) was observed when MMF treatment was entered into the multivariate model instead of study period. Long-term graft survival improved significantly in 1996-2001 compared to 1986-1995 despite older donor age. Modern immunosuppression could have contributed to the improved kidney transplant outcome.

Clinical assessment of mortality risk in renal transplant candidates in Spain.

BACKGROUND: Prediction of mortality in wait-listed patients for kidney transplantation (KT) has not been well elucidated. We assessed whether application of the Charlson comorbidity index (CCI) and other uremia-related comorbidities, not included in the CCI, were associated with mortality in these patients. METHODS: We included 3851 adult patients from the Andalusian Registry who were placed on the waiting list for KT during the study period (1984-2012). A total of 1975 patients received a successful KT and were censored at that point, whereas 1876 were on the waiting list at any time. Multivariate Cox proportional regression analysis and competing risk models, both of which included a propensity score for factors leading to KT, were constructed to examine death in wait-listed patients. RESULTS: Overall mortality on the waiting list was 24%, and cardiovascular disease was the leading cause of death (25%), followed by infections (19%) and malignant disorders (7%). By competing risk models, age older than 50 years (subhazard ratio [SHR] 1.4; 95% CI, 1.1-1.9), CCI score higher than 3 (SHR 2.8; 95% CI, 2.1-3.7), a central venous catheter (SHR 1.8; 95% CI, 1.4-2.2) and unemployed status (SHR 1.7; 95% CI, 1.3-2.2) at dialysis entry were significantly associated with mortality. When these factors were incorporated in a composite risk model, mortality risk increased significantly with increasing risk levels. CONCLUSION: A limited number of comorbidities, easily measurable at entry to dialysis, are associated with mortality in wait-listed patients. This simple clinical assessment may help prioritize high-risk wait-listed patients for receiving an age-matched deceased donor kidney.

Regression of cardiac growth in kidney transplant recipients using anti-m-TOR drugs plus RAS blockers: a controlled longitudinal study.

BACKGROUND: Left ventricular hypertrophy (LVH) is common in kidney transplant (KT) recipients. LVH is associated with a worse outcome, though m-TOR therapy may help to revert this complication. We therefore conducted a longitudinal study to assess morphological and functional echocardiographic changes after conversion from CNI to m-TOR inhibitor drugs in nondiabetic KT patients who had previously received RAS blockers during the follow-up. METHODS: We undertook a 1-year nonrandomized controlled study in 30 non-diabetic KT patients who were converted from calcineurin inhibitor (CNI) to m-TOR therapy. A control group received immunosuppressive therapy based on CNIs. Two echocardiograms were done during the follow-up. RESULTS: Nineteen patients were switched to SRL and 11 to EVL. The m-TOR group showed a significant reduction in LVMi after 1 year (from 62 ± 22 to 55 ± 20 g/m2.7; P=0.003, paired t-test). A higher proportion of patients showing LVMi reduction was observed in the m-TOR group (53.3 versus 29.3%, P=0.048) at the study end. In addition, only 56% of the m-TOR patients had LVH at the study end compared to 77% of the control group (P=0.047). A significant change from baseline in deceleration time in early diastole was observed in the m-TOR group compared with the control group (P=0.019). CONCLUSIONS: Switching from CNI to m-TOR therapy in non-diabetic KT patients may regress LVH, independently of blood pressure changes and follow-up time. This suggests a direct non-hemodynamic effect of m-TOR drugs on cardiac mass.

High incidence of delayed graft function in HIV-infected kidney transplant recipients.

Kidney transplantation (KT) outcomes in human immunodeficiency virus (HIV)-infected recipients are under continuous research. High incidence of early post-transplant complications such as acute rejection has been observed. A multicenter study including HIV-infected patients who underwent KT in Spain, from 2001 to 2011, was performed. The study population included 108 recipients, 36 HIV-infected, and 72 matched HIV-negative KT recipients. HIV-infected recipients developed more delayed graft function (DGF) (52% vs. 21%, P < 0.001). One- and 3-year graft survival was 91.6% and 86.2% in HIV-infected patients, and 97.1% and 94.7% in HIV-negative patients (P = 0.052). In two-variate Cox analysis, HIV infection was not a predictor of graft loss after adjusting for time on dialysis, acute rejection, and DGF. Multivariate analysis for DGF revealed HIV-positive status as independent risk factor. We analyzed the evolution of immunosuppressive and antiretroviral therapy (ART). In HIV-infected patients tacrolimus trough levels were very high in the first week and significantly lower in the second week post-transplant (P = 0.042). Post-transplant ART was significantly changed: protease inhibitors use decreased (P = 0.034) and integrase inhibitor use increased (P < 0.001). DGF is another frequent early complication in HIV-infected recipients that can affect graft survival. Strategies to prevent DGF and antiretroviral regimes with less drug interactions could improve outcomes.

Histology and proteinuria after renal transplantation.

Proteinuria is a nonspecific sign of the troubled renal allograft. Small increases of proteinuria more than 150 mg/d are associated with poor renal allograft survival. During the 90s, it was assumed that chronic allograft nephropathy, defined as the presence of interstitial fibrosis and tubular atrophy, was the histologic lesion responsible for proteinuria and renal function deterioration in most kidneys. Thus, the interest to pursue a histologic diagnosis in patients with proteinuria or renal function deterioration faded during this period. In 2005, the criteria to diagnose chronic humoral rejection, a condition that in the previous year was not distinguished from chronic allograft nephropathy (CAN), were defined. The description of chronic humoral rejection as a major cause of proteinuria and graft loss represented a change of paradigm because it became clear that chronic humoral rejection and other conditions such as recurrence of original disease, de novo glomerulonephritis, polyomavirus infection, and others are responsible for proteinuria. These conditions can be diagnosed on histologic and clinical grounds, provided that special techniques such as C4d, immunofluorescence, immunohistochemistry, electron microscopy, and determination of donor specific antibodies are used. Thus, it became rather clear that proteinuria should be studied by means of a renal biopsy, especially if we take into consideration that there is very poor correlation between the amount of proteinuria and the disease responsible for it. Studies based on surveillance biopsies showed that histologic diagnosis precedes clinical manifestations. Despite the lack of clinical trials, series of patients have shown that different entities respond to different treatments, further reinforcing the idea that early diagnosis and early treatment may contribute to improve graft outcome.

HIV infection and renal transplantation.

BACKGROUND: Some aspects of kidney transplant outcome in human immunodeficiency virus (HIV)-infected patients are still controversial. Besides, published experience is scarce in Europe. METHODS: A multicentre case-control study was designed to analyse the outcome of renal transplant in HIV + patients in Spain. Twenty HIV + patients were compared with a matched cohort of 40 HIV - recipients. RESULTS: Post-transplant follow-up period was 39.98 ± 36.51 months. Pre-transplant dialysis duration and the incidence of pre-transplant opportunistic infections were significantly higher for HIV + patients. Following transplantation, HIV + recipients presented lower incidence of immediate renal function and more acute rejection. Graft survival was lower although the difference was not significant (1 year: 85 vs 97.5%; 5 years: 74.4 vs 91%; log-rank P = 0.058). There was no difference in patient survival rates. Eight patients in each group presented hepatitis C (HCV) infection. Coinfected patients were compared with HIV +/HCV - and HIV -/HCV + recipients. Coinfected patients presented more time on dialysis, greater duration of delayed graft function and lower graft survival (HIV +/HCV + vs HIV +/HCV -: log-rank P = 0.009; HIV +/HCV + vs HIV -/HCV +: log-rank P = 0.02). Conversely, when excluding HCV + patients in both groups, graft survival in HIV + and HIV - patients was similar. CONCLUSIONS: The outcome was good, particularly in non-coinfected patients. Coinfected patients constitute an especially high-risk group for kidney transplantation.