A Heterogeneous Viscosity Flow Model for Liquid Transport through Nanopores Considering Pore Size and Wettability.

The confinement effect in micro- and nanopores gives rise to distinct flow characteristics in fluids. Clarifying the fluid migration pattern in confined space is crucial for understanding and explaining the abnormal flow phenomena in unconventional reservoirs. In this study, flow characteristics of water and oil in alumina nanochannels were investigated with diameters ranging from 21 nm to 120 nm, and a heterogeneous viscosity flow model considering boundary fluid was proposed. Compared with the prediction of the HP equation, both types of fluids exhibit significant flow suppression in nanochannels. As the channel size decreases, the deviation degree increases. The fluid viscosity of the boundary region displays an upward trend as the channel size decreases and the influence of the interaction between the liquid and solid walls intensifies. The thickness of the boundary region gradually decreases with increasing pressure and eventually reaches a stable value, which is primarily determined by the strength of the interaction between the liquid and solid surfaces. Both the pore size and wettability are essential factors that affect the fluid flow. When the space scale is extremely small, the impact of wettability becomes more pronounced. Finally, the application of the heterogeneous flow model for permeability evaluation has yielded favorable fitting results. The model is of great significance for studying the fluid flow behavior in unconventional reservoirs.

Changes in Intestinal Flora From Chronic Renal Failure Complicated With Coronary Heart Disease and its Correlation With Arterial Stiffness Index.

Context: One common and serious cardiovascular complication of chronic renal failure (CRF) is coronary heart disease (CHD). CRF can lead to an imbalance of patients' gut microbiota, and changes in intestinal flora might heavily affect CRF's development. Objective: The study intended to investigate the changes in intestinal flora of patients with CRF complicated with CHD and their relationship with ASI to understand the association of those changes and ASI with CRF comorbid with CHD, with the goal of offering a reliable clinical basis for active prevention and treatment of CRF and CHD in the future. Design: The research team designed a prospective controlled study. Setting: The study took place at the Affiliated Hospital of Hebei University in Baoding, Hebei, China. Participants: Participants were 86 patients with both CRF and CHD and 72 patients with CHD only who had been admitted to the hospital between October 2019 and January 2021. Intervention: The intervention group included participants who had received a diagnosis of CRF complicated with CHD and the control group included participants who had received a diagnosis of CHD only. Outcome Measures: The research team counted participants' intestinal flora and measured their ambulatory blood pressure and arterial stiffness index (ASI) to analyze the correlation of the ASI with the intestinal flora and the related factors impacting CHD in patients with CRF. Results: The monitoring of participants' ambulatory blood pressures showed that the intervention group's day systolic blood pressure (dSBP) and 24h SBP were significantly higher, while the group's day diastolic blood pressure (dDBP) and 24h DBP were significantly lower than those of the control group. The intervention group's levels of lactobacillus, bacteroidaceae, and bifidobacterium were significantly lower than those of the control group, and those intestinal flora were negatively correlated with ASI. The intervention group's levels of Escherichia coli and yeasts were significantly higher than those of the control group, and those intestinal flora were positively correlated with ASI. A significant relationship existed between lactobacillus and yeast and the occurrence of CHD in the CRF participants. Conclusions: Patients with both CRF and CHD have an obvious intestinal-flora imbalance, and the imbalance is strongly bound up with their ASI, which is of great reference significance for novel therapy of such patients and for the clinical application of ASI.

Acute renal failure caused by Sjögren's syndrome and rheumatoid arthritis overlap syndrome.

Introduction: Sjögren's syndrome (SS) and rheumatoid arthritis (RA) are two chronic autoimmune diseases. To date, there have been few reports on the overlap between SS and RA in China, especially regarding correlated acute renal failure cases. Methods: To provide a reference for our clinical peers, this article presents the case report of an elderly female patient who was diagnosed with acute renal failure caused by SS and RA overlap syndrome. Results: We also provide a relevant analysis of SS and RA overlap syndrome treatment. Conclusions: We also provide a relevant analysis of SS and RA overlap syndrome treatment.

Efficacy of tacrolimus monotherapy in primary membranous nephropathy.

Objective: The aim of this study was to observe the remission of primary membranous nephropathy (PMN) and evaluate the efficacy of tacrolimus (TAC) monotherapy for PMN in comparison with TAC combined with a low-dose glucocorticoid (GC) protocol (TAC + GC). Methods: This was tested in a prospective monocentric observational trial of 70 patients with PMN, of whom 34 received TAC (0.05-0.075 mg/kg/day) or 36 received TAC (0.05-0.075 mg/kg/day) and GC (0.3-0.5 mg/kg/day of prednisone). Results: At 3, 6, 9, and 12 months of treatment, the effective rates in the TAC group and the TAC + GC group were similar (P > 0.05). The urinary protein quantification was reduced in patients under both therapeutic protocols, and the differences in the proteinuria quantification at 3, 6, 9, and 12 months of treatment were not statistically significant between the two groups (P > 0.05). The overall incidence of adverse reactions in the TAC group was lower than that in the TAC + GC group (23.5% < 36.1%), and the difference was statistically significant (P < 0.05). Conclusion: TAC monotherapy for PMN could effectively reduce urinary protein quantification and increase serum albumin levels. Compared with TAC + GC, TAC monotherapy for PMN had no difference in efficacy and fewer incidences of adverse reactions.

Determinants of Sarcopenia in Elderly Patients with Chronic Kidney Disease.

INTRODUCTION: This study was conducted to determine the factors affecting the development of sarcopenias in elderly patients with chronic kidney disease (CKD), in order to provide future clinical reference and guidance in preventing the occurrence of sarcopenias in patients with CKD. METHODS: We included 116 CKD patients admitted to affiliated Hospital of Hebei University for retrospective analysis between September 2019 and March 2022. Fifty-one CKD patients with sarcopenias were selected as the observation group (OG) and 65 CKD patients without sarcopenias were considered as the control group (CG). Clinical baseline data such as age and sex were recorded, venous blood was collected for routine examination, and a multi-frequency body composition analyzer was applied to measure patients' body composition. Grip strength, middle arm circumstances (MAC) and triceps skin-fold thickness (TSF) were also measured. Then, patients' sleep quality, nutritional status and negative psychological status were assessed by using the Pittsburgh Sleep Quality Index (PSQI), Malnutrition inflammation score (MIS), and Self-rating Anxiety/Depression Scale (SAS/SDS), respectively. Differences in test results were compared inter-group, and the factors affecting the occurrence of sarcopenias in CKD patients were analyzed by multiple Logistic regression. RESULTS: OG patients were older than CG patients, with a higher number of female patients. Their BMI, bone mass, MAC, serum creatinine (Scr), uric acid (UA) and triglyceride (TG) were lower (P < .05). According to multiple Logistic regression analysis, age, as well as PSQI, MIS, SAS, and SDS scores were the risk factors for sarcopenias in CKD, while BMI, bone mass, MAC, Scr, UA and TG were protective factors (P < .05). CONCLUSION: Age, poor sleep quality, poor nutritional status and negative emotions are independent risk factors for sarcopenias in CKD patients, while BMI, bone mass, MAC, UA, TG, and Scr are independent protective factors.  DOI: 10.52547/ijkd.7537.

Diabetes mellitus with a duration of 26 years combined with IgA nephropathy: A case report and literature review.

Background: The incidence of diabetes mellitus (DM) in China is increasing yearly and has become a major problem plaguing national public health. The diagnosis of diabetic kidney disease (DKD) is based primarily on clinical criteria, and most patients do not receive a formal evaluation by renal biopsy; thus, misdiagnosis and underdiagnosis are common. The incidence of non-diabetic kidney disease (NDKD) is also higher in those with DM. To date, many cases of IgA nephropathy (IgAN) among those with DKD have been reported, while cases of IgAN in patients with long-duration DM who did not develop DKD are less commonly reported. Case description: A 70-year-old male patient with a diabetes duration of 26 years had proteinuria for one year. The clinical manifestations of nephrotic syndrome and IgAN were confirmed by renal biopsy. The patient received targeted treatment for three years with partial alleviation of proteinuria. Conclusion: Renal biopsy might aid in the definitive diagnosis of DKD, NDKD, and NDKD combined with DKD. Precise therapy based on renal pathology might help to improve outcomes in the kidney.

Research on Characterization and Heterogeneity of Microscopic Pore Throat Structures in Tight Oil Reservoirs.

The key to the efficient development of a tight reservoir is its accurate evaluation. In this study, the pore throat structure characteristics of sandstone samples in the study block were analyzed by high-pressure mercury injection technology. According to the characteristics of the capillary pressure curve, the sandstone samples in the study block were divided into three types: the first type has a reservoir permeability greater than 0.7 mD and a core mercury injection saturation of 96% with a good reservoir quality; the second type has a reservoir permeability ranging from 0.4 to 0.7 mD and a core mercury injection saturation of 80% with a moderate reservoir quality; and the third type has a reservoir permeability between 0.1 and 0.4 mD and a core mercury injection saturation of 50% with a poor reservoir quality. Also, high-resolution synchrotron radiation imaging and scanning electron microscopy were used to observe the pore throat structure, connectivity, and microscopic heterogeneity of sandstone samples, showing an increasing level of pore disconnection, serious microscopic heterogeneity, and poor reservoir performance as reservoir permeability declines. As mineral composition tests show, the lithology of the tight sandstone in the target block is mainly medium-grained and fine-grained feldspar lithic sandstone and the longitudinal heterogeneity of lithology and mineral components of tight sandstone is relatively weak at above the centimeter level. Besides, based on the high-pressure mercury injection test data, fractal theory is applied to calculate the fractal dimensions of the three types of reservoirs. The result shows a gradual increase in fractal dimensions with the decrease of reservoir quality, in which the closer the fractal dimension is to 3, the more serious the microscopic heterogeneity is, and the stronger the roughness of the pore surface is. As a result, the more heterogeneous the tight reservoir gets, the more likely the injected fluid is to flow along the developed and connected pore regions.