Kidney transplant recipients may be at a high risk of developing critical coronavirus disease 2019 (COVID‐19) illness due to chronic immunosuppression and comorbidities. We identified hospitalized ...adult kidney transplant recipients at 12 transplant centers in the United States, Italy, and Spain who tested positive for COVID‐19. Clinical presentation, laboratory values, immunosuppression, and treatment strategies were reviewed, and predictors of poor clinical outcomes were determined through multivariable analyses. Among 9845 kidney transplant recipients across centers, 144 were hospitalized due to COVID‐19 during the 9‐week study period. Of the 144 patients, 66% were male with a mean age of 60 (±12) years, and 40% were Hispanic and 25% were African American. Prevalent comorbidities included hypertension (95%), diabetes (52%), obesity (49%), and heart (28%) and lung (19%) disease. Therapeutic management included antimetabolite withdrawal (68%), calcineurin inhibitor withdrawal (23%), hydroxychloroquine (71%), antibiotics (74%), tocilizumab (13%), and antivirals (14%). During a median follow‐up period of 52 days (IQR: 16‐66 days), acute kidney injury occurred in 52% cases, with respiratory failure requiring intubation in 29%, and the mortality rate was 32%. The 46 patients who died were older, had lower lymphocyte counts and estimated glomerular filtration rate levels, and had higher serum lactate dehydrogenase, procalcitonin, and interleukin‐6 levels. In sum, hospitalized kidney transplant recipients with COVID‐19 have higher rates of acute kidney injury and mortality.
In this multinational cohort of 144 kidney transplanted patients from 11 transplant centers in the US and Europe who were hospitalized for COVID‐19, acute kidney injury occurred in 52% and respiratory failure requiring intubation occurred in 29%, with an overall mortality of 32%.
Two coordination polymers (CPs), based on Cu(I)–I double zig-zag chains bearing isonicotinic acid or 3-chloroisonicotinic acid as terminal ligands with molecular recognition capabilities, have been ...synthesized and fully characterized. Both compounds present extended networks with supramolecular interactions directed by the formation of H-bonds between the complementary carboxylic groups, giving supramolecular sheets. The chloro substituent allows establishing additional Cl···Cl supramolecular interactions that reinforce the stability of the supramolecular sheets. These CPs are semiconductor materials; however, the presence of chlorine produces slight changes in the I–Cu–I chains, generating a worse overlap in the Cu–I orbitals, thus determining a decrease in its electrical conductivity value. These experimental results have also been corroborated by theoretical calculations using the study of the morphology of the density of states and 3D orbital isodensities, which determine that conductivity is mostly produced through the Cu–I skeleton and is less efficient in the case of the chloro derivative compound. A fast and efficient bottom-up approach based on the self-assembly of the initial building blocks and the low solutibility of these CPs has proved very useful for the production of nanostructures.
Background
Laparoscopic endoscopic cooperative surgery (LECS) is a safe alternative to endoscopic submucosal dissection (ESD) for select gastric gastrointestinal stromal tumors (GISTs) that are <2 cm ...in size. To date, there have been no randomized studies comparing the feasibility of these two techniques. Therefore, we compared their feasibility and safety using the propensity score matching method in this study.
Methods
This was a single-center, retrospective, propensity score-matched study of patients who underwent resection of selected gastric GISTs between 2004 and 2014. All patients underwent curative resection for pathologically diagnosed small gastric GISTs. The primary aim was to determine intraoperative complications and postoperative courses. To overcome selection biases, we performed a 1:1 match using five covariates, including age, gender, body mass index, Charlson comorbidity index, and tumor location, to generate propensity scores.
Results
In total, 32 patients treated with LECS and 102 patients treated with ESD were balanced into 30 pairs. The rate of intraoperative complications was significantly lower in the LECS group than in the ESD group (
P
= 0.029). LECS patients had less intraoperative bleeding than did ESD patients (15.0 ml range 9.5–50.0 ml vs. 43.5 ml range 22.3–56.0 ml,
P
= 0.004). The two groups had similar postoperative courses. There was no difference in the reoperation rate between the two groups (
P
= 0.112). The ESD group had a shorter operating time than did the LECS group (41.5 min vs. 96.5 min,
P
< 0.001). However, during a follow-up of 57.9 (±28.9) months, the recurrence rate did not differ significantly between the two groups (0.0 vs. 6.7 %, respectively;
P
= 0.256).
Conclusions
LECS for selected gastric GIST patients is feasible and is associated with a better intraoperative outcome and an equal postoperative course compared with the results of ESD.
Background
Despite major advances, multiple myeloma remains an incurable disease. Epidemiological data from high-quality population-based registries are needed to understand the heterogeneous ...landscape of the disease.
Methods
Incidence, mortality and survival in multiple myeloma were comprehensively analyzed in the Girona and Granada population-based cancer registries, over a 23-year study (1994–2016), divided into three periods (1994–2001, 2002–2009 and 2010–2016). Joinpoint regression analysis was used to estimate the annual percentage change in incidence and mortality. Age-standardized net survival was calculated with the Pohar–Perme method.
Results
1957 myeloma patients were included in the study, with a median age of 72 years. Age-standardized incidence and mortality rates decreased over time in both sexes and both rates were higher in males. Five-year age-standardized net survival by period was 27.4% (1994–2001), 38.8% (2002–2009), and 47.4% (2010–2016). Survival improved for all age groups: 32.4%, 74.1% and 78.5% for patients aged 15–49; 27.5%, 44.6%, and 58.5% for those aged 50–69; finally, 24.8%, 25.5%, and 26.3% for the older group.
Conclusion
Incidence remained overall stable throughout the study, with only a small increase for men. Mortality was progressively decreasing in both sexes. Both incidence and mortality were higher in men. Age plays a critical role in survival, with impressive improvement in patients younger than 70 years, but only a minor benefit in those older than 70.
Ultra-high-performance concrete (UHPC) is a special cementitious composite material with outstanding qualities like compressive strength greater than 120 MPa, and outstanding durability in comparison ...to other types of concrete. However, its production implies a large carbon footprint and significant consumption of natural resources such as quartz powder and fine quartz sand, both classified as carcinogenic to humans by the International Agency for Research on Cancer. This study produced a UHPC paste created with greener pozzolans and aggregates compared to current UHPC mixture proportions. In this regard, quartz powder and fine quartz sand were replaced by two different sizes of recycled glass powder. Furthermore, reducing the cement dosage was a goal in optimizing the UHPC mixture. This total replacement of the aggregate and reduction of the cement reduces the carbon footprint and the costs of the final material in two different ways: firstly, by decreasing the use of natural resources to produce quartz powder and sand, and secondly, by using waste material that otherwise would occupy landfill space. To reproduce the findings of this paper in developing countries with limited-quality cement, high C3A locally available cement is used in this research. The latter represents a significant challenge in the production of UHPC. Statistical methodologies such as center composite design and multiobjective optimization were undertaken to develop an efficient, healthy, safe, and environmentally friendly mixture design that meets the ASTM strength criteria for UHPC while maintaining the lowest cement content and the highest waste material dosage. The results showed that the fact that all the ground recycled glass particles have a size of less than 1 mm is not a sufficient condition to avoid the harmful alkali-silica reaction. In addition, it was observed that the high C3A content of the locally available cement had a slight positive effect on the 1-day compressive strength but a significant negative effect on the 28-day compressive strength of the UHPC. Finally, the present investigation demonstrated the feasibility of producing a UHPC that, using a local cement with almost 10% C3A, met the threshold criteria with a large volume use of recycled glass powder representing more than fifty percent by weight of total concrete.
Summary
Bone health is assessed by bone mineral density (BMD). Other techniques such as trabecular bone score and microindentation could improve the risk of fracture’s estimation. Our chronic kidney ...disease (CKD) patients presented worse bone health (density, microarchitecture, mechanical properties) than controls. More than BMD should be done to evaluate patients at risk of fracture.
Introduction
BMD measured by dual-energy X-ray absorptiometry (DXA) is used to assess bone health in end-stage renal disease (ESRD) patients. Recently, trabecular bone score (TBS) and microindentation that can measure microarchitectural and mechanical properties of bone have demonstrated better correlation with fractures than DXA in different populations. We aimed to characterize bone health (BMD, TBS, and strength) and calcium/phosphate metabolism in a cohort of 53 ESRD patients undergoing kidney transplantation (KT) and 94 controls with normal renal function.
Methods
Laboratory workout, lumbar spine/hip BMD measurements (using DXA), lumbar spine TBS, and bone strength were carried out. The latter was assessed with an impact microindentation device, standardized as percentage of a reference value, and expressed as bone material strength index (BMSi) units. Multivariable linear regression was used to study differences between cases and controls adjusted by age, gender, and body mass index.
Results
Among cases, serum calcium was 9.6 ± 0.7 mg/dl, phosphorus 4.4 ± 1.2 mg/dl, and intact parathyroid hormone 214 pg/ml 102–390. Fourteen patients (26.4%) had prevalent asymptomatic fractures in spinal X-ray. BMD was significantly lower among ESRD patients compared to controls: lumbar 0.966 ± 0.15 vs 0.982 ± 0.15 (adjusted
p
= 0.037), total hip 0.852 ± 0.15 vs 0.902 ± 0.13 (adjusted
p
< 0.001), and femoral neck 0.733 ± 0.15 vs 0.775 ± 0.12 (adjusted
p
< 0.001), as were TBS (1.20 1.11–1.30 vs 1.31 1.19–1.43 (adjusted
p
< 0.001)) and BMSi (79 71.8–84.2 vs 82. 77.5–88.9 (adjusted
p
= 0.005)).
Conclusions
ESRD patients undergoing transplant surgery have damaged bone health parameters (density, microarchitecture, and mechanical properties) despite acceptably controlled hyperparathyroidism. Detecting these abnormalities may assist in identifying patients at high risk of post-transplantation fractures.
This review article analyzes the influence of recycled glass (as sand and powder) beyond the durability, rheology and compressive strength of plain UHPC, even exploring flexural and direct tensile ...performance in fiber-reinforced UHPC. Interactions with other mineral admixtures like limestone powder, rice husk ash, fly ash, FC3R, metakaolin and slags, among others, are analyzed. Synergy with limestone powder improves rheology, reducing superplasticizer usage. Research highlights waste glass–UHPC mixtures with reduced silica fume and cement content by over 50% and nearly 30%, respectively, with compressive strengths exceeding 150 MPa, cutting costs and carbon footprints. Furthermore, with the proper fiber dosage, waste glass–UHPC reported values for strain and energy absorption capacity, albeit lower than those of traditional UHPC formulations with high cement, silica fume and quartz powder content, surpassing requirements for demanding applications such as seismic reinforcement of structures. Moreover, durability remains comparable to that of traditional UHPC. In addition, the reported life cycle analysis found that the utilization of glass powder in UHPC allows a greater reduction of embedded CO2 than other mineral additions in UHPC without jeopardizing its properties. In general, the review study presented herein underscores recycled glass’s potential in UHPC, offering economic and performance advantages in sustainable construction.
Detection of posttransplant donor‐specific anti‐HLA antibodies (DSA) constitutes a risk factor for kidney allograft loss. Together with complement activation, NK‐cell antibody‐dependent cell mediated ...cytotoxicity (ADCC) has been proposed to contribute to the microvascular damage associated to humoral rejection. In the present observational exploratory study, we have tried to find a relationship of circulating donor‐specific and nondonor‐specific anti‐HLA antibodies (DSA and HLA non‐DSA) with peripheral blood NK‐cell subsets and clinical features in 393 renal allograft recipients. Multivariate analysis indicated that retransplantation and pretransplant sensitization were associated with detection of posttransplant DSA. Recipient female gender, DR mismatch and acute rejection were significantly associated with posttransplant DSA compared to HLA non‐DSA. In contrast with patients without detectable anti‐HLA antibodies, DSA and HLA non‐DSA patients displayed lower proportions of NK‐cells, associated with increased CD56bright and NKG2A+ subsets, the latter being more marked in DSA cases. These differences appeared unrelated to retransplantation, previous acute rejection or immunosuppressive therapy. Although preliminary and observational in nature, our results suggest that the assessment of the NK‐cell immunophenotype may contribute to define signatures of alloreactive humoral responses in renal allograft recipients.
This single‐center prospective study of kidney transplant recipients shows that patients with detectable anti‐HLA antibodies display lower proportions of NK cells and increased CD56bright and NKG2A+ subsets than patients without antibodies, the latter being more marked in cases with donor‐specific antibodies.
PDF
