Phosphate Kinetics During Weekly Cycle of Hemodialysis Sessions: Application of Mathematical Modeling

Both hyperphosphatemia and hypophosphatemia are associated with increased morbidity and mortality among patients on dialysis. The control of serum phosphate concentration is a considerable clinical problem. Our study aimed to improve understanding of phosphate kinetics in patients on dialysis using mathematical modeling. Three consecutive hemodialysis sessions with breaks of 2–2–3 days were monitored in 25 patients. Phosphate concentration was measured every hour and 45 min after the end of dialysis in blood serum and every 30 min in dialysate during each session. Volume of fluid compartments and body composition were assessed by bioimpedance. The pseudo one‐compartment model was applied to describe the profile of phosphate in blood serum during intra‐ and interdialytic periods of 1‐week cycle of three hemodialysis sessions. Model parameters, such as phosphate internal clearance (K_M) and the rate of phosphate mobilization (R_M), were correlated with the reduction of serum phosphate concentration during dialysis (C_post/C_pre) and with equivalent continuous clearance (ECC) for phosphate. K_M correlated negatively with predialysis serum phosphate concentration. There was significant positive correlation between R_M and age. Postdialysis volume of phosphate central compartment was lower than, but correlated to, extracellular water volume. Parameters of the pseudo one‐compartment model, phosphate internal clearance, and the rate of phosphate inflow to the central compartment (the one accessible for dialysis) from other phosphate body reservoirs correlated with the indices of dialysis adequacy, such as reduction of serum phosphate and ECC. The pseudo one‐compartment model can be successfully extended from a single hemodialysis to the standard weekly cycle of sessions and the model parameters strongly correlate with the adequacy parameters of dialytic removal of phosphate.     

Integrating trauma,self-disturbances,cognitive biases,and personality into a model for the risk of psychosis: a longitudinal study in a non-clinical sample

European Archives of Psychiatry and Clinical Neuroscience - The hypothesis of the psychosis continuum enables to study the mechanisms of psychosis risk not only in clinical samples but in...     

Mining Knowledge of Respiratory Rate Quantification and Abnormal Pattern Prediction

The described application of granular computing is motivated because cardiovascular disease (CVD) remains a major killer globally. There is increasing evidence that abnormal respiratory patterns might contribute to the development and progression of CVD. Consequently, a method that would support a physician in respiratory pattern evaluation should be developed. Group decision-making, tri-way reasoning, and rough set–based analysis were applied to granular computing. Signal attributes and anthropomorphic parameters were explored to develop prediction models to determine the percentage contribution of periodic-like, intermediate, and normal breathing patterns in the analyzed signals. The proposed methodology was validated employing k-nearest neighbor (k-NN) and UMAP (uniform manifold approximation and projection). The presented approach applied to respiratory pattern evaluation shows that median accuracies in a considerable number of cases exceeded 0.75. Overall, parameters related to signal analysis are indicated as more important than anthropomorphic features. It was also found that obesity characterized by a high WHR (waist-to-hip ratio) and male sex were predisposing factors for the occurrence of periodic-like or intermediate patterns of respiration. It may be among the essential findings derived from this study. Based on classification measures, it may be observed that a physician may use such a methodology as a respiratory pattern evaluation-aided method.

     

Early graft function and intrarenal resistant index after kidney transplantation using Biolasol—A new solid organ preservation fluid

Biolasol is a newly developed preserving solution for cold organ storage prior to transplantation. To date, only animal model experiments results are available. The aim of this single-center analysis was to summarize the clinical experience concerning the early post-transplant course of kidney grafts preserved with Biolasol in comparison with other preservation solutions. Before transplantation, 173 kidney grafts were preserved using Biolasol and 240 organs with other solutions (University of Wisconsin—UW, Institute Georges Lopez—IGL-1, or StoreProtect Plus solutions). Early graft function was defined based on serum creatinine concentration at day 3 (<3 mg/dL—immediate graft function, IGF or >3 mg/dL—slow graft function, SGF) or the need of dialysis therapy during first post-operative week (delayed graft function, DGF). The analysis included intrarenal resistive indices measured by Doppler sonography early after transplantation and before discharge from the hospital. IGF was more frequent in patients with organs preserved with IGL-1 (33.5%) and StoreProtect Plus (38.8%) than Biolasol (18.5%), whereas there was no difference in the occurrence of DGF. Both initial and discharge median resistance index values were significantly higher in the Biolasol subgroup (0.77 and 0.75) than in all three other subgroups (P values for all comparisons <.001), also after 1:1 propensity score matching for baseline characteristics. Multiple logistic regression analysis based on the propensity score-matched cohort revealed that the use of Biolasol solution [OR 0.59 (0.35-0.98); P < .05] independently decreased the occurrence of IGF. In our single-center clinical experience, kidney preservation using Biolasol solution was associated with significantly higher intrarenal resistant index in comparison with other preservation fluids, as well as worse early graft function than in the IGL-1 and the StoreProtect Plus subgroups. Long-term follow-up is needed in order to assess the kidney graft and patient survival.     

Microbiological effects in patients with leg ulcers and diabetic foot treated with Lucilia sericata larvae

Lucilia sericata bottle fly worms can be used to heal infected, chronic, or necrotic wounds, including those associated with ulceration and diabetic foot. The study aimed to evaluate changes in the microflora in patients treated with L sericata larvae due to leg ulcers and diabetic foot. One hundred twenty-nine patients diagnosed with lower limb ulceration and diabetic foot were enrolled in the study, of which 80 of them met the eligibility criteria for maggot debridement therapy (MDT). On the contrary, 49 unqualified patients were offered ozone therapy (22 with leg ulcers; 27 with diabetic foot). In each of these patients, a microbiological swab was performed before and after the start of therapy. The group of 80 patients was further divided into four equal groups in terms of the treated area (lower leg vs foot) and the number of larvae/cm² (5 vs 10). Twenty-three particular species of bacteria in the infected wound were studied microbiologically in terms of presence/absence within the wound environment before and after treatment of patients with diabetic foot and lower limb ulceration. It was noted that there was a more intensive bacterial accumulation in the feet of patients compared to legs; furthermore, this applies to almost all analysed species. Diabetes status is also a clinical factor that generates a lower chance of bacterial appearance in the wound environment. Densification of MDT larvae per wound area unit also reduced the chance of the presence of Corynebacterium species, Enterobacteriaceae, Pseudomonas aeruginosa, Staphylococcus aureus MSSA, and Streptococcus coagulase negativa; however, it increased the likelihood of occurrence for Proteus mirabilis and the Proteus species. A microbiological analysis in this non-reference study shows the efficacy of larval therapy for leg and foot ulcers. Rearrangement of the microflora within the wound has been reported as a result of the therapy.     

A single weekly dose of imatinib is sufficient to induce and maintain remission of chronic eosinophilic leukaemia in FIP1L1-PDGFRA-expressing patients

Hypereosinophilic syndrome (HES) is defined as chronic, unexplained hypereosinophilia with organ involvement. A subset of HES patients presents an interstitial deletion in chromosome 4q12, which leads to the expression of an imatinib-responsive fusion gene, FIP1L1-PDGFRA. These patients are diagnosed as chronic eosinophilic leukaemia (CEL). We treated seven CEL and HES patients, six of which expressed FIP1L1-PDGFRA , with imatinib using initial daily doses ranging from 100 to 400 mg. In a remission maintenance phase, the patients were treated with imatinib once weekly. All imatinib-treated patients achieved a complete haematological remission (CHR), and five of the six patients with FIP1L1-PDGFRA expression exhibited molecular remission. The decreased imatinib doses were as follows: 200 mg/week in three patients, 100 mg/week in two patients and 100 mg/d in the remaining two patients. For remission maintenance, imatinib doses were set at 100 mg/week in five patients and 200 mg/week in two patients. At a median follow-up of 30 months all patients remained in CHR and FIP1L1-PDGFRA expression was undetectable in five of the six FIP1L1-PDGFRA -expressing patients. These data suggest that a single weekly dose of imatinib is sufficient to maintain remission in FIP1L1-PDGFRA - positive CEL patients.     

Associations between gait patterns, brain lesion factors and functional recovery in stroke patients

Brain CT scans and neurological condition were evaluated in 74 stroke patients. Firstly, we found that using a classification-tree technique based on CT scan parameters (an innovative method, analyzing four parameters simultaneously) coincided with our previously proposed kinematic artificial neural network (ANN) classification technique for 71.3% of patients. Lesion size and location were found to be the most significant CT scan predictors of gait classification. Secondly, we sought to gauge post-rehabilitation functional recovery in patients within the same three groups of gait pattern. We found significant differences in scores between the three gait pattern groups, before and after rehabilitation (Kruskal-Wallis test, p<0.001), while significant improvement was observed in each group (Wilcoxon text; p<0.01). We conclude that patient classification into pathological gait groups on the basis of gait or CT scan parameters may serve as an early predictor of future functional outcome.     

Biomarkers in melanoma: stage III and IV disease

The prognosis associated with Stage III melanoma is variable (17-65% 5-year survival) and primarily influenced by the number of lymph nodes involved, the presence of ulceration in a primary lesion, and the tumor burden present in each lymph node. In patients with metastatic (Stage IV) melanoma, the prognosis remains dismal (6-18% 5-year survival) and is influenced primarily by the sites (and extent) of metastatic involvement. Serum lactate dehydrogenase is the only prognostic biomarker useful in metastatic melanoma and it has been incorporated into the 2002 American Joint Committee on Cancer tumor, node, metastasis staging system. In this review, the known prognostic factors in Stage III and IV melanoma are reviewed. Selected investigational therapies and associated biomarkers are also discussed.