A time-averaged serum bicarbonate-based nomogram to predict the probability of residual kidney function preservation for patients undergoing peritoneal dialysis

OBJECTIVE

Residual kidney function (RKF) is an important prognostic indicator in peritoneal dialysis (PD) patients. So far, there are no prediction tools available for RKF, and the association between serum bicarbonate and RKF has received little attention in patients with PD. We aimed to develop a nomogram for the preservation of RKF based on the time-averaged serum bicarbonate (TA-Bic) levels.

PATIENTS AND METHODS

A prediction model was established by conducting a retrospective cohort study of 151 PD patients who had been treated at the First Affiliated Hospital of Anhui Medical University. The nomogram was developed using a multivariate Cox regression model. The discrimination, calibration, and clinical utility of the model were evaluated by the C-index, receiver operating curve (ROC) curve, calibration curve, and decision curve analysis.

RESULTS

In the elderly PD onset, higher baseline values of residual glomerular filtration rate, total Kt/V and higher TA-Bic levels were identified as protective predictors of RKF loss. The nomogram was conducted on the basis of the minimum value of the Akaike Information Criterion and Bayesian Information Criterion with a reasonable C-index of 0.766, showing great discrimination, proper calibration, and high potential for clinical practice. Through the total score of the nomogram, the patients were classified into the high-risk group and low-risk group, and a higher cumulative incidence of complete RRF loss was found in the high-risk group compared with the patients in the low-risk group.

CONCLUSIONS

The novel predictive nomogram model can predict the probability of RKF preservation in long-term PD patients with high accuracy. Future studies are needed to externally validate the current nomogram before clinical application.

Prognostic and immune roles of UROC1 in human cancers: from mechanism exploration of NAFLD and HCC to pan-cancer analysis

OBJECTIVE

Both non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) are prevalent diseases worldwide. This study aimed to explore the underlying mechanisms of NAFLD and HCC and identify new therapeutic targets for human cancers.

MATERIALS AND METHODS

NAFLD and HCC gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA) were utilized to identify co-expressed genes associated with NAFLD and HCC. Public databases were consulted to find common targets of NAFLD and HCC. Enrichment analysis and CIBERSORT techniques were employed to analyze the pathways enriched with DEGs and the attributes of infiltrating immune cells. Furthermore, the expression data of UROC1 and clinical information of patients were acquired from The Cancer Genome Atlas (TCGA) database. Finally, the expression of the UROC1 was validated by immunohistochemistry (IHC).

RESULTS

Through a comprehensive bioinformatics analysis, eight hub genes (CCL2, CCR2, IL6, CSF3R, ATL2, SESN3, UROC1, FIGNL1) were identified. Enrichment analysis indicated that inflammatory and immune response may be common features between NAFLD and HCC. CIBER-SORT analysis revealed an imbalance of plasma cells and macrophages in NAFLD and HCC. Pan-cancer analysis demonstrated that UROC1 expression was related to clinical outcomes and tumor immunity in various cancers. Moreover, a strong correlation was exhibited between UROC1 expression and crucial elements, including tumor mutation burden (TMB), microsatellite instability (MSI), multiple immune checkpoints (ICP), and tumor microenvironment (TME). Importantly, an adverse clinical prognosis of HCC was linked to decreased UROC1 expression, which was consistent with IHC results.

CONCLUSIONS

We identified eight hub genes (CCL2, CCR2, IL6, CSF3R, ATL2, SESN3, UROC1, FIGNL1), which may become early diagnostic and therapeutic targets for NAFLD and HCC. The pan-cancer analysis of UROC1 provides new evidence for its broad application prospects in the field of HCC and other cancers.

[Analysis of early diagnosis and prevention techniques for occupational pneumoconiosis based on patent perspectives in China's coal industry]

Occupational pneumoconiosis in the coal industry is an occupational disease that seriously endangers coal miners' health. Early diagnosis and prevention techniques are significant in controlling its incidence rate and reducing its harm. This article takes the patent data related to the early diagnosis and prevention of occupational pneumoconiosis in the coal industry, published from 1985 to 2021, as the research object. It uses tools such as the Derwent Data Analyzer (DDA) software, the Patyee Database, and the PatSnap Database to analyze the technological development trend and characteristics in this field from aspects of growth trend, primary patent holders, IPC classification layout, value, and research and development hotspots. The results show that the number of patent applications in this field indicates a rapid growth trend, mainly in the hands of Shandong Energy Group Co. Ltd., Shandong University of Science and Technology, China University of Mining and Technology, and other institutions or enterprises. Patent technology mainly involves spray dust reduction, dust removal fans, dust masks, and other aspects with high patent value and innovation ability. This article provides a new perspective and reference for preventing, diagnosing, and treating occupational pneumoconiosis in the coal industry.

Risk factors and etiological characteristics of urinary tract infection in hospitalized continuous ambulatory peritoneal dialysis patients

OBJECTIVE

This study aimed to explore the risk factors and etiological characteristics of urinary tract infection (UTI) in continuous ambulatory peritoneal dialysis (CAPD) patients.

PATIENTS AND METHODS

A total of 90 CAPD patients with UTI comprised the infection group, while 32 CAPD patients without UTI constituted the control group. The risk factors and etiological characteristics of UTI were analyzed.

RESULTS

Of the 90 bacterial strains isolated, 30 were Gram-positive (33.3%) and 60 were Gram-negative (66.7%). Urinary stones or urinary tract structural changes were more prevalent in the infection group (71.1%) than in the control group (46.9%) (χ² = 6.076, p = 0.018). The proportion of patients with residual diuresis less than 200 ml was higher in the infection group (50%) than in the control group (15.6%) (χ² = 11.533, p = 0.001). The distribution of primary disease differed between the two groups. Patients in the infection group had higher CAPD vintage, levels of triglycerides, fasting blood glucose, blood creatinine, blood phosphorus, and calcium-phosphorus product than those in the control group. Multivariate binary logistic regression analysis indicated that residual diuresis less than 200 ml (OR = 3.519, p = 0.039) and urinary stones or structural changes (OR = 4.727, p = 0.006) were independent risk factors for UTI.

CONCLUSIONS

Urine cultures of CAPD patients with UTI contained a complex distribution of pathogenic bacteria. Urinary stones or structural changes and residual diuresis less than 200 ml were independent risk factors for UTI.

SIRT3 retards intervertebral disc degeneration by anti-oxidative stress by activating the SIRT3/FOXO3/SOD2 signaling pathway

OBJECTIVE

The objective of this paper is to determine whether SIRT3 could retard intervertebral disc degeneration and study the mechanism.

MATERIALS AND METHODS

We chose the 3-month mice to establish intervertebral disc degeneration model and study the effect of SIRT3 on the intervertebral disc by Western blotting, quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), immunohistochemistry. Mouse nucleus pulposus cells were cultured to study the exact mechanism.

RESULTS

The expression of SIRT3 was decreased in degenerated human nucleus pulposus. Intervertebral discs of mice treated with theacrine expressed more collagen II and less collagen X. In addition, nucleus pulposus cells stimulated with interleukin-1β (IL-1β) expressed less SIRT3 than that in the control group and nucleus pulposus cells with SIRT3 overexpress vectors expressed more collagen II FOXO3a and superoxide dismutase 2 (SOD2), indicating that SIRT3 could improve the intervertebral disc degeneration by anti-oxidative stress.

CONCLUSIONS

SIRT3 is a protective factor for intervertebral discs and can reduce oxidative stress in the intervertebral disc.

FK506 reduces albuminuria through improving podocyte nephrin and podocin expression in diabetic rats

Objective and design

Several works in the setting of early experimental diabetic nephropathy using anti-inflammatory drugs, such as the calcineurin inhibitor FK506, have shown prevention of the development or amelioration of renal injury including proteinuria. The exact mechanisms by which anti-inflammatory drugs lower the albuminuria have not been still clarified well.

Materials

The diabetic rats were induced by using streptozotocin.

Treatment

The diabetic rats were subjected to oral FK506 treatment at a dose of 0.5 or 1.0 mg/kg daily for 4 weeks.

Methods

Renal histology for the ultrastructural evaluation was determined by electron microscope, followed by analyses of renal nephrin and podocin and detection of renal iNOS⁺ macrophages and NF-κB-p-p65⁺.

Results

Elevated 24-h urinary albumin excretion rate was markedly attenuated by FK506 treatment. In diabetic model rats, FK506 treatment at a dose of 0.5 or 1.0 mg/kg significantly increased the expression of nephrin and podocin when compared to control. As expected, rats in control diabetic group had an increase in GBM thickening and foot process effacement when compared to normal rats; increased GBM thickening and foot process effacement were ameliorated by FK506 treatment with 0.5 and 1.0 mg/kg. Histologically, there was marked accumulation of ED-1⁺cells (macrophages) in diabetic kidneys, and FK506 treatment failed to inhibit it. In contrast, FK506 treatment at 0.5 and 1.0 mg/kg doses significantly inhibited the elevated ED-1⁺/iNOS⁺ cells in the kidneys of diabetic rats. ED-1⁺/NF-κB-p-p65⁺ cells were significantly increased in positive diabetic kidneys compared to those of normal rats. FK506 treatment at 0.5 and 1.0 mg/kg significantly attenuated the elevated ED-1⁺/NF-κB-p-p65⁺ cells in diabetic kidneys. Additionally, a positive correlation was observed between ED-1⁺/iNOS⁺ cells and albuminuria (r = 0.87, p < 0.05). Likewise, ED-1⁺/iNOS⁺ cells were correlated negatively with both nephrin and podocin protein (r = −0.70, p < 0.05; r = −0.68, p < 0.05, respectively).

Conclusion

Our results show that FK506 not only upregulates expression of nephrin and podocin but also inhibits macrophage activation to protect against podocyte injury.

Association of white matter hyperintensities with low serum 25-hydroxyvitamin D levels

BACKGROUND AND PURPOSE

Vitamin D deficiency is associated with cognitive impairment in the elderly and with increased white matter T2 hyperintensities in elderly debilitated patients. We investigated the relationship between serum vitamin D and brain MR findings in adult outpatients.

MATERIALS AND METHODS

Brain MR studies of 56 patients ages 30-69 years were selected when vitamin D level had been obtained within 90 days of the MRI. White matter T2 hyperintensities were characterized by size and location by two neuroradiologists. Manual volumetric analysis was assessed in patients more than 50 years of age.

RESULTS

The entire cohort showed a significant negative relationship between serum 25-hydroxyvitamin D and the number of confluent juxtacortical white matter T2 hyperintensities (P = .047). The cohort ages 50 years and older showed stronger correlation between confluent white matter T2 hyperintensities and serum 25-hydroxyvitamin D in the juxtacortical region; number (P = .015) and size of white matter T2 hyperintensities (P = .048). Atrophy was not significantly related to serum 25-hydroxyvitamin D by radiologist visual analysis or by the bicaudate ratio.

CONCLUSIONS

We found a significant relationship between vitamin D and white matter T2 hyperintensities in independent adult outpatients, especially over the age of 50 years.

Overexpression of α-2,6 sialyltransferase stimulates propagation of human influenza viruses in Vero cells

Human influenza viruses are major concern as the leading cause of global pandemics. In infecting cells, they preferentially bind to sialyloligosaccharides containing terminal N-acetyl sialic acid linked to galactose by an α-2,6-linkage (NeuAcα2,6Gal). The amount of NeuAcα2,6Gal in Vero cells, which are predominantly used for production of influenza vaccines over the past 30 years, may not be as high as that in epithelial cells of human respiratory tract, what leads to the suboptimal virus growth in Vero cells. In this study, we stably transfected Vero cells with cDNA of human α-2,6-sialyltransferase (SIAT1), an enzyme catalyzing α-2,6-sialylation of galactose on glycoproteins. Overexpression of SIAT1 in the transfected Vero cells (Vero-SIAT1 cells) was confirmed by Western blot analysis and immunofluorescence microscopy. Vero-SIAT1 cells expressed 7 times higher amounts of NeuAcα2,6Gal, but 3 times lower amounts of NeuAcα2,3Gal as compared to parental Vero cells. Furthermore, the influenza viruses A (H1N1 and H3N2) and B grew in Vero-SIAT1 cells to the higher titers than in Vero cells. Taken together, these results imply that Vero-SIAT1 cells are useful not only for the propagation of human influenza viruses, but also for the preparation of influenza vaccines.

Renoprotective effects of combination of angiotensin converting enzyme inhibitor with mycophenolate mofetil in diabetic rats

OBJECTIVE AND DESIGN

Previously it was shown that blocking of the renin-angiotensin system (RAS) by angiotensin converting enzyme (ACE) inhibitors, or suppression of inflammatory responses by immunosuppressive drugs such as mycophenolate mofetil (MMF) could attenuate renal injury in diabetic rats. Whether RAS blockade combined with an immunosuppressive drug provides superior renoprotection against diabetic nephropathy has not been clearly delineated.

MATERIALS

Diabetes was induced by injection of streptozotocin after uninephrectomy.

TREATMENT

Rats were randomly separated into five groups: control, diabetes, diabetes treated with enalapril (an ACE inhibitor, 10 mg/kg/d by gastric gavage), diabetes treated with MMF (10 mg/kg/d by gastric gavage), or diabetes treated with a combination of both agents and were followed for 8 weeks.

METHODS

24 h urinary albumin excretion rate (AER) was determined, renal injury was evaluated, immunohistochemistry for ED-1 macrophage marker, intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1) were performed, and expression of transforming growth factor (TGF)-beta1 protein was determined by Western blotting analysis.

RESULTS

Diabetes was associated with a considerable increase in AER. Both enalapril and MMF retarded the increase in albuminuria, which was nearly completely abrogated by combination therapy. Increased glomerular volume and tubulointerstitial injury index in diabetic rats was attenuated by treatment with either enalapril or MMF and further reduced by the combination of the two. Elevated malondialdehyde levels in renal tissue were reduced by enalapril or MMF and, more effectively, by combined enalapril with MMF. Renal overexpression of ICAM-1 was not retarded by enalapril and attenuated by MMF or combined enalapril with MMF. Combination therapy was associated with a superior suppression of diabetes-induced macrophage recruitment and overexpression of MCP-1 and TGFbeta1 compared to either monotherapy in renal tissue.

CONCLUSION

The combination of enalapril and MMF confers superiority over monotherapy in renoprotection, a mechanism which may be at least partly correlated with synergistic suppression of increased macrophage recruitment and overexpression of MCP-1 and TGF-beta1 in renal tissue in diabetic rats.

Medical image compression by discrete cosine transform spectral similarity strategy

Due to the bandwidth and storage limitations, medical images must be compressed before transmission and storage. However, the compression will reduce the image fidelity, especially when the images are compressed at lower bit rates. The reconstructed images suffer from blocking artifacts and the image quality will be severely degraded under the circumstance of high compression ratios. In this paper, we present a strategy to increase the compression ratio with simple computational burden and excellent decoded quality. We regard the discrete cosine transform as a bandpass filter to decompose a sub-block into equal-sized bands. After a band gathering operation, a high similarity property among bands is found. By the utilization of similarity property, the bit rate of compression can be greatly reduced. Meanwhile, the characteristics of the original image are not sacrificed. Thus, it can avoid the misdiagnosis of diseases for doctors. Simulations are carried to different kind of medical images to demonstrate that the proposed method achieves better performance when compared to other existing transform coding scheme as the JPEG in terms of bit rate and quality. For the case of angiogram image, its peak signal-to-noise-ratio gain is 13.5 dB at the same bit rate of 0.15 bits per pixel when comparing to the JPEG compression. As to the other kind of medical images, their benefits are not so obvious as an angiogram image; however, the gains for them are still from 4-8 dB at high compression ratios. Two doctors from the Department of Radiology, National Cheng Kung University Hospital, Tainan, Taiwan, R.O.C., and Chang Gung Medical Hospital, Kaoshuing, Taiwan, R.O.C., are invited to verify the decoded image quality; the diagnoses of all the test images are correct when the compression ratios are below 20.

Congenital lactic acidosis: evaluation of the properties of the a199t natural variant of human pyruvate dehydrogenase e1alpha by in vitro mutation

One cause of congenital lactic acidosis is a mutation in the E1 alpha-subunit of the pyruvate dehydrogenase multienzyme complex. Little is known about the consequences of these mutations at the enzymatic level. Here we study the A199T mutation by expressing the protein in Escherichia coli. The specific activity is 25% of normal and the K(m) for pyruvate is elevated by 10-fold. Inhibitors of lactate dehydrogenase might be a useful therapy for patients with such mutations.

Mutagenesis at asp27 of pyruvate decarboxylase from Zymomonas mobilis. Effect on its ability to form acetoin and acetolactate

Pyruvate decarboxylase (PDC) is one of several enzymes that require thiamin diphosphate (ThDP) and a bivalent cation as essential cofactors. The three-dimensional structure of PDC from Zymomonas mobilis (ZMPDC) shows that Asp27 (D27) is close to ThDP in the active site, and mutagenesis of this residue has suggested that it participates in catalysis. The normal product of the PDC reaction is acetaldehyde but it is known that the enzyme can also form acetoin as a by-product from the hydroxyethyl-ThDP reaction intermediate. This study focuses on the role of D27 in the production of acetoin and a second by-product, acetolactate. D27 in ZMPDC was altered to alanine (D27A) and this mutated protein, the wild-type, and two other previously constructed PDC mutants (D27E and D27N) were expressed and purified. Determination of the kinetic properties of D27A showed that the affinity of D27A for ThDP is decreased 30-fold, while the affinity for Mg2+ and the Michaelis constant for pyruvate were similar to those of the wild-type. The time-courses of their reactions were investigated. Each mutant has greatly reduced ability to produce acetaldehyde and acetoin compared with the wild-type PDC. However, the effect of these mutations on acetaldehyde production is greater than that on acetoin formation. The D27A mutant can also form acetolactate, whereas neither of the other mutants, nor the wild-type PDC, can do so. In addition, acetaldehyde formation and/or release are reversible in wild-type ZMPDC but irreversible for the mutants. The results are explained by a mechanism involving thermodynamic and geometric characteristics of the intermediates in the reaction.

An adaptive 3-D discrete cosine transform coder for medical image compression

In this communication, a new three-dimensional (3-D) discrete cosine transform (DCT) coder for medical images is presented. In the proposed method, a segmentation technique based on the local energy magnitude is used to segment subblocks of the image into different energy levels. Then, those subblocks with the same energy level are gathered to form a 3-D cuboid. Finally, 3-D DCT is employed to compress the 3-D cuboid individually. Simulation results show that the reconstructed images achieve a bit rate lower than 0.25 bit per pixel even when the compression ratios are higher than 35. As compared with the results by JPEG and other strategies, it is found that the proposed method achieves better qualities of decoded images than by JPEG and the other strategies.

Measurement of the total cross section for hadronic production by e(+)e(-) annihilation at energies between 2.6-5 GeV

Using the upgraded Beijing Spectrometer, we have measured the total cross section for e(+)e(-) annihilation into hadronic final states at center-of-mass energies of 2.6, 3.2, 3.4, 3.55, 4.6, and 5.0 GeV. Values of R, sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->&mgr;(+)&mgr;(-)), are determined.

Laboratory evaluation on the toxic effects of bednets impregnated with permethrin against malaria mosquitos

In the laboratory, bednets impregnated with 250mg ai/m2 and 500mg ai/m2 permethrin caused respectively the mean mortalities of 86.6% within 13 months and 87.2% within 17 months on laboratory-bred An. sinensis, while they caused average mortalities of 58.3% within 4 months and 73.8% within 10 months on An. dirus respectively. The bioassay results of KT50 and LT50 on the two species showed that KT50 is shorter than LT50 after exposure to the treated bednets. The ratio is 1:2.16 - 1:3.05. It was observed Anopheles had obviously secondary knocked down after exposure to the treated bednets and there is obvious resurgent after Anopheles have been knocked down. When the temperature goes up the resurgence gets shorter, the resurgence rate gets higher and the mortality gets lower. It showed that permethrin has stronger knocking down effect than killing effect.

[Application of microsurgical technique in the intrasinus renalis pyeloureteroplasty in pelvic atresia in children]

Seven cases of pelvic atresia in children were treated by the intrasinus renalis pyeloureteroplasty with the application of microsurgical technique. The site of pelviureteric anastomosis was unobstructed and the hydronephrosis was greatly improved through postoperative examinations of intravenous urography and renogram. This procedure provides clear field, simple performance and high successful rate. The prevention of complete pelviureteric laceration and pelvic atresia in children, the advantages of the microsurgical technique, and the operation precautions are discussed.

Experimental studies on peripheral nerve regeneration enhanced by nerve growth factor

The effect of exogenous nerve growth factor (NGF) examined on the neural repair of adult rabbit sciatic nerve was evaluated in the present study. A nerve regeneration chamber was created by suturing the proximal and distal ends of a transected sciatic nerve into a silicone chamber. A gap of 6 mm in chamber was left after removal of a 3 mm piece of nerve in the distal ends and insertion of the proximal and distal stumps into the chamber. Animals were operated on bilaterally, one side of the chamber was filled with a 1 mg/ml NGF/normal saline (NS) (experimental) and the contralateral side with NS (control). The regenerated nerves from within the silicone chamber were dissected and fixed 1 to 5 weeks following surgery for histological studies at both the light microscopic and ultrastructural levels. The NGF chamber showed a more mature regenerated nerve based on a larger diameter of the regenerated nerve trunk, a great number of axons, and thicker myelin sheaths.

Clinical application of the forearm island skin and fascia flap with posterior interosseous artery pedicle--report of 15 cases

The present paper reported 15 cases, in which skin and fascia forearm island flap with posterior interosseous artery pedicle was applied. It was found that this flap has the advantages of stable vessels, abundance in blood supply and good circulation, without sacrificing the main arteries of the forearm. As a result, it is an ideal method for repair and reconstruction of the hand and forearm.