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Sodium-glucose cotransporter-2 (SGLT-2) inhibitors are a class of novel oral anti-hyperglycemic agents which are increasingly used in clinical practice. SGLT-2 inhibitors improve glycemic control and cardiorenal outcomes, promote weight loss, and reduce blood pressure. Randomized controlled trials have demonstrated that SGLT-2 inhibitors reduce proteinuria and delay progression of kidney disease in patients with albuminuria. However, whether SGLT-2 inhibitors have similar benefits in patients with nephrotic-range proteinuria has not been well established. Evidence to date has been limited to case reports, case series and secondary analyses of randomized controlled trials. This is the first comprehensive review on the effectiveness of SGLT-2 inhibitors for the treatment of patients with nephrotic-range albuminuria or proteinuria. Overall findings support a likely beneficial role of SGLT-2 inhibitors in reducing proteinuria and delaying chronic kidney disease progression in patients with nephrotic-range proteinuria.

Neutralization of Omicron subvariants by different bivalent vaccines have not been well evaluated. This study characterized neutralization against Omicron subvariants in 98 individuals receiving dialysis or with a kidney transplant receiving the BNT162b2 (BA.4/BA.5) or mRNA-1273 (BA.1) bivalent COVID-19 vaccine. Neutralization against Omicron BA.1, BA.5, BQ.1.1, and XBB.1.5 increased by 8-fold one month following bivalent vaccination. In comparison to wild-type (D614G), neutralizing antibodies against Omicron-specific variants were 7.3-fold lower against BA.1, 8.3-fold lower against BA.5, 45.8-fold lower against BQ.1.1, and 48.2-fold lower against XBB.1.5. Viral neutralization was not significantly different by bivalent vaccine type for wild-type (D614G) (P=0.48), BA.1 (P=0.21), BA.5 (P=0.07), BQ.1.1 (P=0.10), nor XBB.1.5 (P=0.10). Hybrid immunity conferred higher neutralizing antibodies against all Omicron subvariants. Given that both BNT162b2 (BA.4/BA.5) and mRNA-1273 (BA.1) induced similar neutralization against all Omicron subvariants, this suggests that bivalent vaccines confer protection even when they are antigenically divergent from the circulating variant.

Kidney transplant recipients (KTRs) have a diminished response to SARS-CoV-2 vaccination compared with immunocompetent individuals. Deeper understanding of antibody responses in KTRs following third-dose vaccination would enable identification of those who remain unprotected against Omicron.We profiled antibody responses in KTRs pre- and at 1 and 3 mo post-third-dose SARS-CoV-2 mRNA-based vaccine. Binding antibody levels were determined by ELISA. Neutralization against wild type, Beta, Delta, and Omicron (BA.1) variants was determined using a SARS-CoV-2 spike-pseudotyped lentivirus assay.Forty-four KTRs were analyzed at 1 and 3 mo (n = 26) post-third dose. At 1 mo, the proportion of participants with a robust antibody response had increased significantly from baseline, but Omicron-specific neutralizing antibodies were detected in just 45% of KTRs. Median binding antibody levels declined at 3 mo, but the proportion of KTRs with a robust antibody response was unchanged; 38.5% KTRs maintained Omicron-specific neutralization at 3 mo. No clinical variables were significantly associated with Omicron-neutralizing antibodies, but antireceptor binding domain titers appeared to identify those with Omicron-specific neutralizing capacity.Over 50% of KTRs lack Omicron-specific neutralization capacity 1 mo post-third mRNA-vaccine dose. Antibody levels of responders were well preserved at 3 mo. Anti receptor binding domain antibody titers may identify patients with a detectable Omicron-neutralizing antibody response.

Background: Kidney transplant recipients (KTR) have a diminished response to SARS-CoV-2 vaccination in comparison to immunocompetent individuals. Deeper understanding of the antibody response in KTRs following third-dose vaccination would enable identification of those who remain unprotected against Omicron and require additional treatment strategies. Methods: We profiled antibody responses in KTRs pre- and at one and three months post-third-dose SARS-CoV2 mRNA-based vaccine. Anti-spike and anti-RBD IgG levels were determined by ELISA. Neutralization against wild-type, Beta, Delta and Omicron (BA.1) variants was determined using a SARS-CoV-2 spike pseudotyped lentivirus assay. Results: 44 KTRs were analysed at 1 and 3 months (n=26) post-third-dose. At one month, the proportion of participants with a robust antibody response had increased significantly from baseline, but Omicron-specific neutralizing antibodies were detected in just 45% of KTRs. Median binding antibody levels declined at 3 months, but the proportion of KTRs with a robust antibody response was unchanged. 38.5% KTRs maintained Omicron-specific neutralization at 3 months. No clinical variables were significantly associated with detectable Omicron neutralizing antibodies, but anti-RBD titres appeared to identify those with Omicron-specific neutralizing capacity. Conclusion: Over 50% of KTRs lack an Omicron-specific neutralization response 1 month following a third mRNA-vaccine dose. Among responders, binding and neutralizing antibody responses were well preserved at 3 months. Anti-RBD antibody titres may be a useful identifier of patients with detectable Omicron neutralizing antibody response. Trial registration: Clinical Trials Ontario: ID 3604

Diversity in sex and gender are important considerations in the pathogenesis, prognostication, research, and management of diabetic kidney disease (DKD). Sex and gender differences in the disease risk, disease-specific mechanisms, and outcomes in DKD may be attributed to biological differences between males and females at the cellular and tissue level, inconsistencies in the diagnostic and assessment tools used in chronic kidney disease and DKD, as well societal differences in the way men, women, and gender-diverse individuals self-manage and interact with health care systems. This review outlines key considerations related to the impact of sex on DKD, specifically elaborating on how they contribute to observed differences in disease epidemiology, pathogenesis, and treatment strategies. We also highlight the effect of gender on DKD progression and care.

BACKGROUND: Vaccination studies in the hemodialysis population have demonstrated decreased antibody response compared with healthy controls, but vaccine effectiveness for preventing SARS-CoV-2 infection and severe disease is undetermined. METHODS: We conducted a retrospective cohort study in the province of Ontario, Canada, between December 21, 2020, and June 30, 2021. Receipt of vaccine, SARS-CoV-2 infection, and related severe outcomes (hospitalization or death) were determined from provincial health administrative data. Receipt of one and two doses of vaccine were modeled in a time-varying cause-specific Cox proportional hazards model, adjusting for baseline characteristics, background community infection rates, and censoring for non-COVID death, recovered kidney function, transfer out of province, solid organ transplant, and withdrawal from dialysis. RESULTS: Among 13,759 individuals receiving maintenance dialysis, 2403 (17%) were unvaccinated and 11,356 (83%) had received at least one dose by June 30, 2021. Vaccine types were BNT162b2 (n=8455, 74%) and mRNA-1273 (n=2901, 26%); median time between the first and second dose was 36 days (IQR 28–51). The adjusted hazard ratio (HR) for SARS-CoV-2 infection and severe outcomes for one dose compared with unvaccinated was 0.59 (95% CI, 0.46 to 0.76) and 0.54 (95% CI, 0.37 to 0.77), respectively, and for two doses compared with unvaccinated was 0.31 (95% CI, 0.22 to 0.42) and 0.17 (95% CI, 0.1 to 0.3), respectively. There were no significant differences in vaccine effectiveness among age groups, dialysis modality, or vaccine type. CONCLUSIONS: COVID-19 vaccination is effective in the dialysis population to prevent SARS-CoV-2 infection and severe outcomes, despite concerns about suboptimal antibody responses.

SGLT2 inhibitors have emerged as a key disease-modifying therapy to prevent the progression of chronic kidney disease (CKD). These agents prevent decline in kidney function through reduction in glomerular hypertension mediated through tubuloglomerular feedback independent of their effect on glycemic control. The proliferation of clinical trials on SGLT2 inhibitors has rapidly expanded the approved clinical indications for these agents beyond patients with diabetes mellitus (DM). We review the current indications for SGLT2 inhibitors in patients with and without diabetic kidney disease, including new evidence for use in patients with heart failure with or without reduced ejection fraction, stage 4 CKD, and chronic glomerulonephritis. The EMPA-KIDNEY trial was recently stopped early for efficacy suggesting that SGLT2 inhibitors may soon be indicated for patients with CKD without albuminuria. We review practical considerations for prescription of SGLT2 inhibitors, including the anticipated acute decline in estimated glomerular filtration rate (eGFR) on initiation, initiating the lowest dosage used in clinical trials, volume status considerations, and adverse event mitigation. Combination therapy in patients with DM may be considered with agents, including glucagon-like peptide-1 receptor agonists (GLP-1-RAs), novel mineralocorticoid receptor antagonists, and selective endothelin receptor antagonists to reduce residual albuminuria and cardiovascular risk.

BACKGROUND: Testing for antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been instrumental in detecting previous exposures and analyzing vaccine-elicited immune responses. Here, we describe a scalable "Made-in-Canada" solution that can detect and quantify SARS-CoV-2 antibodies, discriminate between natural infection- and vaccination-induced responses, and assess antibody-mediated inhibition of the spike-angiotensin converting enzyme 2 (ACE2) interaction. METHODS: We developed a set of methods and reagents to detect SARS-CoV-2 antibodies by enzyme-linked immunosorbent assay (ELISA). The main assays focus on the parallel detection of immunoglobulin (Ig)Gs against the spike trimer, its receptor binding domain (RBD), and the nucleocapsid (N) protein. These antigens are complemented by a detection antibody (human anti-IgG fused to horseradish peroxidase (HRP)) and a positive control reference antibody (recombinant IgG against the RBD), permitting intra- and inter-laboratory comparisons. Using this toolkit and commercial reagents, we optimized automated ELISAs on two different high throughput platforms to measure antibody responses to SARS-CoV-2 antigens. The assays were calibrated to a reference standard from the World Health Organization. We also automated a surrogate neutralization (sn)ELISA that measures inhibition of ACE2-Spike or -RBD interactions by antibodies using biotinylated ACE2. RESULTS: Our individual IgG-based ELISAs measure antibody levels in single-point measurements in reference to a standard antibody curve to accurately distinguish non-infected and infected individuals (area under the curve > 0.96 for each assay). Positivity thresholds can be established in individual assays using precision-recall analysis (e.g., by fixing the false positive rate), or more stringently, by scoring against the distribution of the means of negative samples across multiple assays performed over several months. For seroprevalence assessment (in a non-vaccinated cohort), classifying a sample as positive if antibodies were detected for at least 2 of the 3 antigens provided the highest specificity. In vaccinated cohorts, increases in anti-spike and -RBD (but not -N) antibodies are observed. Here, we present detailed protocols to perform these assays using either serum/plasma or dried blood spots both manually and on two automated platforms, and to express the results in international units to facilitate data harmonization and inter-study comparisons. We also demonstrate that the snELISA can be performed automatically at single points, increasing the scalability of this functional assay for large seroprevalence studies. INTERPRETATION: The ability to measure antibodies to three viral antigens and identify neutralizing antibodies capable of disrupting spike-ACE2 interactions in high-throughput assays enables large-scale analyses of humoral immune responses to SARS-CoV-2 infection and vaccination. The "Made-in-Canada" set of protein reagents, produced at the National Research Council of Canada are publicly available to enable the up-scaling of standardized serological assays, permitting nationwide data comparison and aggregation.

ImportanceHemodialysis patients have an exceptionally high mortality from COVID-19 and this patient population often has a poor response to vaccinations. Randomized controlled trials for COVID-19 vaccines included few patients with kidney disease, therefore vaccine immunogenicity is uncertain in this population.ObjectiveEvaluate the SARS-CoV-2 antibody response in chronic hemodialysis patients following one versus two doses of BNT162b2 COVID-19 vaccination compared to health care worker controls and convalescent serum.DesignProspective observational cohort study.SettingSingle centre study in Toronto, Ontario, Canada.Participants142 in-centre hemodialysis patients and 35 health care worker controls.ExposureBNT162b2 (Pfizer-BioNTech) COVID-19 vaccine.Main Outcomes and MeasuresSARS-CoV-2 IgG antibodies to the spike protein (anti-spike), receptor binding domain (anti-RBD), and nucleocapsid protein (anti-NP) were measured in 66 hemodialysis patients receiving one vaccine dose following a public health policy change, 76 patients receiving two vaccine doses, and 35 health care workers receiving two vaccine doses.ResultsDetectable anti-NP suggestive of natural SARS-CoV-2 infection was detected in 15/142 (11%) of patients at baseline while only three patients had prior RT-PCR confirmed COVID-19. Two additional patients contracted COVID-19 after receiving two doses of vaccine. In patients receiving a single BNT162b2 dose, seroconversion occurred in 53/66 (80%) for anti-spike and 35/66 (55%) for anti-RBD by 28 days post dose, but only 15/66 (23%) and 4/66 (6%), respectively attained a robust response as defined by reaching the median level of anti-spike and anti-RBD in convalescent serum from COVID-19 survivors. In patients receiving two doses of BNT162b2 vaccine, seroconversion occurred in 69/72 (96%) for anti-spike and 63/72 (88%) for anti-RBD by 2 weeks following the second dose while 52/72 (72%) and 43/76 (41%) reached the median convalescent serum level of anti-spike and anti-RBD, respectively. In contrast, 35/35 (100%) of health care workers exceeded the median level of anti-spike and anti-RBD found in convalescent serum 2-4 weeks after the second dose.Conclusions and RelevanceThis study confirms poor immunogenicity 28 days following a single dose of BNT162b2 vaccine in the hemodialysis population, supporting adherence to recommended vaccination schedules, and avoiding delay of the second dose in these at-risk individuals.Key PointsQuestionWhat is the serologic response to the BNT162b2 COVID-19 vaccine in hemodialysis patients?FindingsIn this prospective observational study, humoral response was compared in 66 hemodialysis patients sampled 28 days after receipt of one dose of vaccine to 76 patients who received two doses of vaccine sampled 14 days after the second dose. Among those receiving one dose, 6% had anti-RBD response above the median level of convalescent serum versus 41% who received two doses.MeaningGiven that hemodialysis patients exhibit a poor humoral response to a single dose of BNT162b2 vaccine, the second dose should not be delayed.

Key Points Question What is the serologic response to the BNT162b2 COVID-19 vaccine in patients undergoing hemodialysis? Findings In this cohort study of 142 patients receiving hemodialysis, humoral response was compared in 66 patients sampled 28 days after receipt of 1 dose of vaccine with 76 patients who received 2 doses of vaccine sampled 14 days after the second dose. Among those receiving 1 dose, 6% had antireceptor binding domain response above the median level of convalescent serum vs 41% of those who received 2 doses at 1 week, increasing to 60% by 2 weeks. Meaning The findings of this study suggest that, given that patients receiving hemodialysis appeared to exhibit a poor humoral response to a single dose of BNT162b2 vaccine, the second dose should not be delayed., Importance Patients undergoing hemodialysis have a high mortality rate associated with COVID-19, and this patient population often has a poor response to vaccinations. Randomized clinical trials for COVID-19 vaccines included few patients with kidney disease; therefore, vaccine immunogenicity is uncertain in this population. Objective To evaluate the SARS-CoV-2 antibody response in patients undergoing chronic hemodialysis following 1 vs 2 doses of BNT162b2 COVID-19 vaccination compared with health care workers serving as controls and convalescent serum. Design, Setting, and Participants A prospective, single-center cohort study was conducted between February 2 and April 17, 2021, in Toronto, Ontario, Canada. Participants included 142 patients receiving in-center hemodialysis and 35 health care worker controls. Exposures BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine. Main Outcomes and Measures SARS-CoV-2 IgG antibodies to the spike protein (anti-spike), receptor binding domain (anti-RBD), and nucleocapsid protein (anti-NP). Results Among the 142 participants undergoing maintenance hemodialysis, 94 (66%) were men; median age was 72 (interquartile range, 62-79) years. SARS-CoV-2 IgG antibodies were measured in 66 patients receiving 1 vaccine dose following a public health policy change, 76 patients receiving 2 vaccine doses, and 35 health care workers receiving 2 vaccine doses. Detectable anti-NP suggestive of natural SARS-CoV-2 infection was detected in 15 of 142 (11%) patients at baseline, and only 3 patients had prior COVID-19 confirmed by reverse transcriptase polymerase chain reaction testing. Two additional patients contracted COVID-19 after receiving 2 doses of vaccine. In 66 patients receiving a single BNT162b2 dose, seroconversion occurred in 53 (80%) for anti-spike and 36 (55%) for anti-RBD by 28 days postdose, but a robust response, defined by reaching the median levels of antibodies in convalescent serum from COVID-19 survivors, was noted in only 15 patients (23%) for anti-spike and 4 (6%) for anti-RBD in convalescent serum from COVID-19 survivors. In patients receiving 2 doses of BNT162b2 vaccine, seroconversion occurred in 69 of 72 (96%) for anti-spike and 63 of 72 (88%) for anti-RBD by 2 weeks following the second dose and median convalescent serum levels were reached in 52 of 72 patients (72%) for anti-spike and 43 of 72 (60%) for anti-RBD. In contrast, all 35 health care workers exceeded the median level of anti-spike and anti-RBD found in convalescent serum 2 to 4 weeks after the second dose. Conclusions and Relevance This study suggests poor immunogenicity 28 days following a single dose of BNT162b2 vaccine in the hemodialysis population, supporting adherence to recommended vaccination schedules and avoiding delay of the second dose in these at-risk individuals., This cohort study examines the immune response of patients receiving maintenance hemodialysis to vaccination with 1 vs 2 doses of the BNT162b2 vaccine.

Rationale & Objective Hemodialysis patients are at increased risk for COVID-19 transmission due, in part, to difficulty maintaining physical distancing. Our hemodialysis unit experienced a COVID-19 outbreak despite following symptom-based screening guidelines. We describe the course of the COVID-19 outbreak and the infection control measures taken for mitigation. Study Design Retrospective cohort study Setting & Participants 237 maintenance hemodialysis patients and 93 hemodialysis staff at a single hemodialysis centre in Toronto, Canada. Exposure Universal screening of patients and staff with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Outcomes The primary outcome was detection of SARS-CoV-2 in nasopharyngeal samples from patients and staff using reverse transcriptase-polymerase chain reaction (RT-PCR) . Analytical Approach Descriptive statistics were used for clinical characteristics and the primary outcome. Results Eleven (4.6%) of 237 hemodialysis patients and 11 of 93 (12%) staff members had a positive RT-PCR test for SARS-CoV-2. Among individuals testing positive, 12 of 22 (55%) were asymptomatic at time of testing, and 7 of 22 (32%) were asymptomatic for the duration of follow-up. One patient was hospitalized at the time of SARS-CoV-2 infection and four additional patients with positive tests were subsequently hospitalized. Two patients (18%) required admission to the intensive care unit. After 30 days follow-up no patients had died or required mechanical ventilation. No hemodialysis staff required hospitalization. Universal droplet and contact precautions were implemented during the outbreak. Hemodialysis staff with SARS-CoV-2 infection were placed on home quarantine regardless of symptom status. Patients with SARS-CoV-2 infection including asymptomatic individuals were treated with droplet and contact precautions until confirmation of negative SARS-CoV-2 RT-PCR testing. Analysis of the outbreak identified two index cases with subsequent nosocomial transmission within the dialysis unit and in shared shuttle buses to the hemodialysis unit. Limitations Single centre study. Conclusions Universal SARS-CoV-2 testing and universal droplet and contact precautions in the setting of an outbreak appeared to be effective in preventing further transmission., Graphical abstract, Plain Language Summary: The COVID-19 pandemic has presented unique challenges to patients on hemodialysis. Despite having risk factors for severe infection, dialysis patients must visit healthcare facilities thrice weekly, where physical distancing is challenging. Despite protocols in place to identify and isolate symptomatic individuals, we report a COVID-19 outbreak in a hemodialysis unit in Toronto, Ontario, which prompted the screening of all hemodialysis patients and most staff for SARS-CoV-2 infection detected in nasopharyngeal swabs specimens, regardless of symptoms. Eleven of 237 (4.6%) hemodialysis patients and 11 of 93 (12%) of staff tested positive for COVID-19. Notably 55% of those testing positive were asymptomatic at the time of testing. This study demonstrates the importance of universal testing in stopping the spread of COVID-19 during an outbreak.

Background and objectives Regulatory agencies warn about the risk of AKI with levetiracetam use on the basis of information from case reports. We conducted this study to determine whether new levetiracetam use versus nonuse is associated with a higher risk of AKI. Design, setting, participants, & measurements This was a population-based retrospective cohort study of adults with epilepsy in Ontario, Canada. Patients who received a new outpatient prescription for levetiracetam between January 1, 2004 and March 1, 2017 were matched to two nonusers on stage of CKD, recorded seizure in the prior 90 days, and logit of a propensity score for levetiracetam use. The primary outcome was a hospital encounter (emergency department visit or hospitalization) with AKI within 30 days of cohort entry. Secondary outcomes were AKI within 180 days and change in the concentration of serum creatinine. We assessed the primary outcome using health care diagnosis codes. We evaluated the change in the concentration of serum creatinine in a subpopulation with laboratory measurements. Results We matched 3980 levetiracetam users to 7960 nonusers (mean age 55 years, 51% women). Levetiracetam use was not significantly associated with a higher risk of AKI within 30 days (13 [0.33%] events in levetiracetam users and 21 [0.26%] events in nonusers [odds ratio, 1.24; 95% confidence interval, 0.62 to 2.47]). Similarly, there was no significant association with AKI within 180 days (odds ratio, 0.70; 95% confidence interval, 0.43 to 1.13). The change in the concentration of serum creatinine did not significantly differ between levetiracetam users and nonusers. Conclusions In this population-based study levetiracetam use was not associated with a higher risk of AKI. Podcast This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2018_12_11_Yau_Podcast.mp3

De novo uridine-diphosphate-N-acetylglucosamine (UDP-GlcNAc) biosynthesis requires glucose, glutamine, acetyl-CoA and uridine, however GlcNAc salvaged from glycoconjugate turnover and dietary sources also makes a significant contribution to the intracellular pool. Herein we ask whether dietary GlcNAc regulates nutrient transport and intermediate metabolism in C57BL/6 mice by increasing UDP-GlcNAc and in turn Golgi N-glycan branching. GlcNAc added to the drinking water showed a dose-dependent increase in growth of young mice, while in mature adult mice fat and body-weight increased without affecting calorie-intake, activity, energy expenditure, or the microbiome. Oral GlcNAc increased hepatic UDP-GlcNAc and N-glycan branching on hepatic glycoproteins. Glucose homeostasis, hepatic glycogen, lipid metabolism and response to fasting were altered with GlcNAc treatment. In cultured cells GlcNAc enhanced uptake of glucose, glutamine and fatty-acids, and enhanced lipid synthesis, while inhibition of Golgi N-glycan branching blocked GlcNAc-dependent lipid accumulation. The N-acetylglucosaminyltransferase enzymes of the N-glycan branching pathway (Mgat1,2,4,5) display multistep ultrasensitivity to UDP-GlcNAc, as well as branching-dependent compensation. Indeed, oral GlcNAc rescued fat accumulation in lean Mgat5−/− mice and in cultured Mgat5−/− hepatocytes, consistent with N-glycan branching compensation. Our results suggest GlcNAc reprograms cellular metabolism by enhancing nutrient uptake and lipid storage through the UDP-GlcNAc supply to N-glycan branching pathway.

Functional disability is defined as the need for assistance with self-care tasks.To document changes in functional status over time among older prevalent renal transplant recipients.Single center, prospective, follow-up study.Single center, tertiary care transplant center.Patients, with a functioning kidney transplant, aged 65 years or older who underwent assessment of functional status approximately 12 months previously.Validated tools used included Barthel Index, the Lawton-Brody Scale of Instrumental Activities of Daily Living, the Timed Up and Go test, the Veterans Specific Activity Questionnaire, the Mini-Cog, and dynamometer handgrip strength.Outpatient assessment by a trained observer.Of the 82 patients previously studied, 64 (78%) patients participated in the follow-up study (mean age 70.5 ± 4.4 years, 58% male, 55% diabetic). Among those completing functional status measures, 32 (50%) had functional disability at baseline. Over the 1-year period, 11 (17%) of these patients experienced progressive functional decline, 6 (9%) exhibited no change, and 15 (23%) had functional recovery. Eleven patients (17%) initially independent, developed new-onset disability. One of the strongest predictors of progressive functional decline was having 1 or more falls in the previous year.Assessments were performed only on 2 occasions separated by approximately 1 year.Fluctuations in disability states are common among older adults living with renal transplants. Episodes of functional disability may place individuals at higher risk of persistent and/or progressive disability.La déficience fonctionnelle se définit comme le besoin pour une personne d’être assistée dans ses activités et soins quotidiens.L’étude visait à documenter les variations dans l’état fonctionnel qui se constatent au fil du temps chez les personnes âgées receveuses d’une greffe rénale.Il s’agit d’une étude de suivi prospective qui s’est tenue dans un seul centre de soins tertiaires en transplantation.Une cohorte de patients âgés de 65 ans et plus ayant reçu une greffe rénale et dont l’évaluation de l’état fonctionnel avait été faite dans les 12 mois précédant l’intervention.Les outils validés suivants ont servi à colliger les données : l’indice Barthel, l’échelle d’activités instrumentales de la vie courante de Lawton (L’évaluation des patients externes a été effectuée par un observateur formé à cet effet.Des 82 patients étudiés précédemment, 64 (78 %) ont participé à l’étude de suivi; leur âge moyen était de 70,5 ± 4,4 ans, 58 % étaient des hommes et 55 % souffraient de diabète. Parmi les patients qui ont complété les mesures de l’état fonctionnel, 32 (50 %) présentaient des déficiences fonctionnelles au départ. Au cours de l’année, 11 (17 %) patients ont vu leur état fonctionnel décliner progressivement, 6 (9 %) n’ont connu aucun changement de leur état et 15 (23 %) ont vu leur capacité fonctionnelle rétablie. Par ailleurs, au cours de la même période, on a constaté l’apparition d’une nouvelle incapacité pour onze patients (17 %) considérés au départ comme indépendants. On a observé que le fait d’avoir chuté une ou plusieurs fois au cours de l’année précédente s’avérait l’un des meilleurs facteurs prédictifs d’un déclin fonctionnel progressif.L’évaluation des patients n’a été réalisée qu’à deux reprises, et celles-ci étaient séparées d’une période d’environ un an.Les variations de l’état fonctionnel sont fréquentes chez les personnes âgées ayant subi une transplantation rénale. Les épisodes d’incapacité fonctionnelle sont susceptibles d’exposer le patient à un plus grand risque de déclin fonctionnel persistant ou progressif.

Using the available observations in 1699, 1865–1866, and 1965, an orbit has been recomputed for periodic comet 55P/Tempel–Tuttle, the parent body of the Leonid meteors. The comet's motion was numerically integrated back in time for two millennia and ephemerides were computed for each perihelion return. Chinese observations of the comet in 1366 are well represented, and possible (but not definite) observations of the comet in October 1234 and January 1035 have been identified. The Leonid meteors have been observed since AD 902. Prior to the eighth century, no Leonid meteors should have been visible because the comet's orbit passed too far outside that of the Earth. By using previously recorded accounts of the Leonid meteor showers and storms as a guide, predictions for the forthcoming Leonid displays in November of 1996–1999 are provided. The 1998 and 1999 events hold the most promise for an impressive Leonid meteor display, although there seems little likelihood that the great storms of 1833 and 1966 will be repeated at this apparition.

Statistics of witnessed and recovered meteorite falls found in Chinese historical texts for the period from 700 B.C. to A.D. 1920 are presented. Several notable features can be seen in the binned distribution as a function of time. An apparent decrease in the number of meteorite reports in the 18th century is observed. An excess of observed meteorite falls in the period from 1840 to 1880 seems to correspond to a similar excess in European data. A chi sq probability test suggest that the association between the two data sets are real. Records of human casualities and structural damage resulting from meteorite falls are also given. A calculation based on the number of casualty events in the Chinese meteorite records suggests that the probability of a meteroite striking a human is far greater than previous estimates. However, it is difficult to verify the accuracy of the reported casualty events.

The orbit of P/Swift-Tuttle is investigated by way of a long-term integration forward to AD 2392 and backward to 703 BC. Two of its previous returns prior to the telescopic period, in AD 188 and 69 BC, are identified in Chinese records. No other observations of P/Swift-Tuttle have been found. The non-gravitational forces that affect the motion of most active comets appear to be negligible for this comet, suggesting that either the comet outgasses radially toward the Sun and in a symmetric fashion about perihelion and/or it is far more massive than periodic comets of comparable activity (e.g. P/Halley). Our successful integration is consistent with all the observed returns of the comet

The treatment of biomass burning (BB) carbonaceous particles in the Multiangle Imaging SpectroRadiometer (MISR) Standard Aerosol Retrieval Algorithm is assessed, and algorithm refinements are suggested, based on a theoretical sensitivity analysis and comparisons with near-coincident AERONET measurements at representative BB sites. Over the natural ranges of BB aerosol microphysical and optical properties observed in past field campaigns, patterns of retrieved Aerosol Optical Depth (AOD), particle size, and single scattering albedo (SSA) are evaluated. On the basis of the theoretical analysis, assuming total column AOD of 0.2, over a dark, uniform surface, MISR can distinguish two to three groups in each of size and SSA, except when the assumed atmospheric particles are significantly absorbing (mid-visible SSA approx.0.84), or of medium sizes (mean radius approx.0.13 pin); sensitivity to absorbing, medium-large size particles increases considerably when the assumed column AOD is raised to 0.5. MISR Research Aerosol Retrievals confirm the theoretical results, based on coincident AERONET inversions under BB-dominated conditions. When BB is externally mixed with dust in the atmosphere, dust optical model and surface reflection uncertainties, along with spatial variability, contribute to differences between the Research Retrievals and AERONET. These results suggest specific refinements to the MISR Standard Aerosol Algorithm complement of component particles and mixtures. They also highlight the importance for satellite aerosol retrievals of surface reflectance characterization, with accuracies that can be difficult to achieve with coupled surface-aerosol algorithms in some higher AOD situations.

[1] Although the current Multiangle Imaging Spectroradiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite passive remote sensing midvisible aerosol optical thickness (AOT) products are accurate overall to about 0.05 or 20%, they differ systematically on a global, monthly average basis, by about 0.03 to 0.05. Some key climate change and other applications require accuracies of 0.03 or better. The instruments are sufficiently stable and well characterized, and have adequate signal-to-noise, to realize such precision. However, assumptions made in the current standard aerosol retrieval algorithms produce AOT biases that must be addressed first. We identify the causes of AOT discrepancies over dark water under typical, relatively low AOT conditions and quantify their magnitudes on the basis of detailed analysis. Examples were selected to highlight key issues for which there are coincident MISR, MODIS, and Aerosol Robotic Network (AERONET) observations. Instrument calibration and sampling differences, assumptions made in the MISR and MODIS standard algorithms about ocean surface boundary conditions, missing particle property or mixture options, and the way reflectances used in the retrievals are selected each contribute significantly to the observed differences under some circumstances. Cloud screening is also identified as a factor, though not fully examined here, as are the relatively rare high-AOT cases over ocean. Specific algorithm upgrades and further studies indicated by these findings are discussed, along with recommendations for effectively using the currently available products for regional and global applications.