Application of urinary N-acetyl-β-D-glucosaminidase combined with serum retinol-binding protein in early detection of diabetic nephropathy

BACKGROUND Diabetic nephropathy(DN)is a microangiopathy of type 2 diabetes mellitus(T2DM),which can damage the kidney through various ways and mechanisms due to the nature of the disease,involving the renal interstitium and glomeruli.However,in the early stage of the disease,patients only showed kidney volume increase and glomerular hyperthyroidism,and typical symptoms that are difficult to arouse individual attention were noticed.AIM To observe the expression of serum retinol-binding protein(RBP)and urinary Nacetyl-β-D-glucosaminidase(NAG)in patients with DN,and to analyze their value in disease prediction,so as to provide new targets for early diagnosis and treatment of DN.METHODS The baseline data of 50 T2DM patients treated in our hospital between January 2021 and December 2022 were retrospectively reviewed and included in group A.The baseline data of 50 patients with type 2 DN admitted to our hospital during the same period were collected and included in group B.The baseline data and serum RBP and urine NAG expression were compared between the two groups to analyze their value in the early prediction of DN.RESULTS There was no significant difference in age,gender,duration of diabetes,combined hyperlipidemia and combined hypertension between the two groups(P>0.05);the expression of urinary NAG and serum RBP in group B was higher than that in group A,and the difference was statistically significant(P<0.05);a multiple logistic regression model was established,and the results showed that urinary NAG and serum RBP were related to the presence or absence of injury in diabetic patients,and overexpression of urinary NAG and serum RBP may be risk factors for renal injury in T2DM patients(OR>1,P<0.05);receiver operating curve curve was plotted,and the results showed that the area under the curve of urinary NAG and serum RBP expression alone and in combination for predicting DN was>0.80,and the predictive value was satisfactory;bivariate Spearman linear correlation analysis showed that there was a positive correlation between urinary NAG and serum RBP expression in patients with DN(r=0.566,P=0.000).CONCLUSION The increased expression of urinary NAG and serum RBP may be the risk factors leading to the progression of T2DM to DN.The possibility of DN can be considered in patients with urinary NAG and serum RBP overexpression by examining the expression of urinary NAG and serum RBP in patients with T2DM in clinical practice.

Study on The Method of Quantitative Analysis of Serum Ferritin and Soluble Transferrin Receptor with Protein Microarray Technology

Objective To establish and evaluate a protein serum ferritin （SF） and soluble transferrin receptor microarray method for combined measurement of （sTfR）. Methods Microarrayer was used to print both anti-SF antibodies I and anti-sTfR antibodies I on each protein microarray. Anti-SF antibodies II and anti-sTfR antibodies II were used as detection antibodies and goat antibodies coupled to Cy3 were used as antibodies Ill. The detection conditions of the quantitative analysis method for simultaneous measurement of SF and sTfR with protein microarray were optimized and evaluated. The protein microarray was compared with commercially available traditional tests with 26 serum samples. Results By comparison experiment, mouse monoclonal antibodies were chosen as the probes and contact printing was chosen as the printing method. The concentrations of SF and sTfR probes were 0.5 mg/mL and 0.5 mg/mL respectively, while those of SF and sTfR detection antibodies were 5 μg/mL and 0.36 μg/mL respectively. Intra- and inter-assay variability was between 3.26% and 18.38% for all tests. The regression coefficients comparing protein microarray with traditional test assays were better than 0.81 for SF and sTfR. Conclusion The present study has established a protein microarray method for combined measurement of SF and sTfR.

The Effect of Silica Dust Exposure on the Serum Clara Cell Protein 16 Levels in Chinese Workers

Pneumoconiosis is a systemic occupational disease that commonly manifests as diffuse fibrosis of the lungs caused by long-term inhalation of silica dust in the production process. The development of pneumoconiosis is a chronic and progressive process;once it occurs, it is irreversible, and gradually develops into lung injury and respiratory failure, and can cause death regardless of exposure to dust. The incidence of pneumoconiosis is the highest in China and the direct and indirect economic loss as a result of pneumoconiosis is approximately 9 billion yuan per year.

Study on the correlation and predictive value of serum pregnancyassociated plasma protein A, triglyceride and serum 25-hydroxyvitamin D levels with gestational diabetes mellitus

BACKGROUND Gestational diabetes mellitus(GDM)is a concern due to its rapid increase in incidence in recent years.AIM To investigate the correlation and predictive value of serum pregnancyassociated plasma protein A(PAPP-A),triglyceride(TG),and 25-hydroxyvitamin D[25-(OH)D]with GDM in early pregnancy.METHODS A total of 99 patients in early pregnancy admitted to Peking University International Hospital from November 2015 to September 2017 were included,and underwent a fasting glucose test and oral glucose tolerance test screening at 24-28 wk of pregnancy.Of these cases with GDM,51 were assigned to group A and the remaining 48 cases without GDM were enrolled in group B.Serum PAPP-A,TG and 25-(OH)D in the two groups were compared and their correlation with blood sugar was analyzed.In addition,their diagnostic value in GDM was determined using receiver operating characteristic(ROC)curve analysis.RESULTS Group A had markedly lower serum PAPP-A and 25-(OH)D levels and a significantly higher serum TG level than group B,with statistical significance(P<0.05).Furthermore,Pearson analysis identified that PAPP-A and 25-(OH)D levels were negatively correlated with fasting blood glucose(FBG)levels(r=-0.605,P<0.001),(r=-0.597,P<0.001),while TG and FBG levels were positively correlated(r=0.628,P<0.001).The sensitivity,specificity,area under the curve(AUC)and optimal cut-off value of serum PAPP-A level in the diagnosis of GDM were 72.55%,82.35%,0.861 and 16.340,respectively,while the sensitivity of TG in diagnosing GDM was 86.27%,the specificity was 66.67%,the AUC was 0.813,with an optimal cut-off value of 1.796.The corresponding sensitivity,specificity,AUC and optimal cut-off value of serum 25-(OH)D were 64.71%,70.59%,0.721 and 23.140,respectively.Moreover,multivariate logistic regression analysis revealed that FBG,vascular endothelial growth factor,Flt-1,serum PAPP-A,TG,and 25-(OH)D were related risk factors leading to GDM in patients.CONCLUSION Serum PAPP-A,TG,and 25-(OH)D levels are all correlated with blood glucose changes in GDM,and are independent factors affecting the occurrence of GDM and have certain value in the diagnosis of GDM.

Acupuncture effects on serum myelin basic protein and remyelination following 30 minutes and 2 hours of ischemia in a rat model of cerebral ischemia-reperfusion injury

BACKGROUND： Acupuncture treatment on injured cerebral axons has shown to provide efficacy in clinical practice. It is unknown whether acupuncture produces therapeutic effects by protecting injured cerebral myelin in ischemic stroke. OBJECTIVE： To test whether acupuncture provides protection for injured cerebral myelin, based on quantitative data from cerebral ischemia-reperfusion rats, and to compare the effects of early and late acupuncture on serum myelin basic protein （MBP） content and remyelination of the ischemic internal capsule.DESIGN, TIME AND SETTING： A randomized, controlled experiment was performed at the Neurobiological Laboratory, Sichuan University from March 2005 to March 2006. MATERIALS： ＂Hua Tuo＂ Brand filiform needles were produced by the Medical Instrument Factory of Suzhou, China.METHODS： A total of 52 adult, healthy, male, Sprague Dawley rats were randomly assigned to four groups： control （n = 4）, model （n = 16）, early acupuncture （n = 16）, and late acupuncture （n = 16）. The focal cerebral ischemia-reperfusion model was established by middle cerebral artery occlusion in the right hemisphere using the modified thread embolism method in the latter three groups. Early and late acupuncture groups underwent acupuncture after ischemia for 30 minutes and 2 hours using the Xingnaokaiqiao needling method, respectively. Acupoints were ＂Neiguarf＇ （PC 6） and ＂Sanyinjiao＂ （SP 6） on the bilateral sides, as well as ＂Shuigou＇ （DU 26） and ＂Baihui＂ （DU 20） with stimulation for 1 minute at each acupoint. Acupuncture at all acupoints was performed two or three times while the needle was retained, once per day. No special handling was administered to the control clroup.MAIN OUTCOME MEASURES： For each group, remyelination of the internal capsule was observed by Pal-Weigert＇s myelin staining and serum MBP content was detected using enzyme-linked immunosorbent assay method on days 1,3, 5, and 7 following ischemia-reperfusion injury.RESULTS： Compared with the control group, massive demyelination of the internal capsule occurred, and serum MBP content increased in the model group （P 〈 0.05）. Compared with the model group, the extent of demyelination in the internal capsule was less distinct and serum MBP content was significantly less in the early and late acupuncture group （P 〈 0.01 ）. Compared with the late acupuncture group, serum MBP content reached a peak later and the peak value was less in the early acupuncture group. CONCLUSION： Results suggest that acupuncture exerts a protective effect on injured cerebral myelin in ischemia-reperfusion rats by reducing serum MBP content and promoting remyelination. The study also suggests that the effect of early acupuncture is superior to late acupuncture.

Protein Microarrays for Quantitative Detection of PAI-1 in Serum

Objective： Plasminogen activator inhibitor-1 （PAI-1）, one crucial component of the plasminogen activator system, is a major player in the pathogenesis of many vascular diseases as well as in cancer. High levels of PAI-1 in breast cancer tissue are associated with poor prognosis. The aim of this study is to evaluate rigorously the potential of serum PAI-1 concentration functioning as a general screening test in diagnostic or prognostic assays. Methods： A protein-microarray-based sandwich fluorescence immunoassay （FIA） was developed to detect PAI-1 in serum. Several conditions of this microarray-based FIA were optimized to establish an efficacious method. Serum specimens of 84 healthy women and 285 women with breast cancer were analyzed using the optimized FIA microarray. Results： The median serum PAI-1 level of breast cancer patients was higher than that of healthy women （109.7 ng/ml vs. 63.4 ng/ml）. Analysis of covariance revealed that PAI-1 levels of the two groups were significantly different （P0.001） when controlling for an age effect on PAI-1 levels. However, PAI-1 values in TNM stage I？IV patients respectively were not significantly different from each other. Conclusion： This microarray-based sandwich FIA holds potential for quantitative analysis of tumor markers such as PAI-1.

Effects of Dietary Protein and Fat Levels on Growth Performance and Serum Biochemical Parameters of Male Mink

This experiment was conducted to evaluate the effects of dietary protein and fat levels on growth performance and serum biochemical parameters of male minks during the growing period. A total, of 90 healthy male minks at the age of 60 d were randomly assigned into six groups with 15 replicates per group and one mink per replicate. The minks were fed six experimental diets with two protein levels （32% and 36% ） and three fat levels （ 10% , 20% and 30% ） for a 7-day preliminary period and then for 60-day experimental period. The results showed that the final body weight and average daily weight gain （ADWG） were significantly higher in low-protein, middle-fat group and low-protein, high-fat group than those in low-protein, low-fat group and high-protein, low-fat group （P 〈 0. O1 ）. The final weight and ADWG were increased with dietary fat level increasing, and the two indices of 20% and 30% fat groups were significantly higher than those of 10% fat groups （ P 〈 0. O1 ）. The ratio of feed intake to weight gain （F/G） in low-protein, high-fat group was the lowest, which was significantly lower than that in low- protein, low-fat group and high-protein, high-fat group （P 〈 0.05 ）. Serum urea nitrogen （UN） in low-protein, high-fat group was significantly lower than that in other groups （P 〈 0. 01 ）. Serum alanine transaminase （ALT） activity in 32% protein groups was significantly higher than that in 36% protein groups （P 〈 O. 05）. Serum triglyceride （TG） content in low-protein, high-fat group and high-protein, high-fat group was significantly higher than that in low-protein, low-fat group and high-protein, low-fat groups （P 〈 0.05 ）. Serum TG, total cholesterol （TCHO） and high-density lipoprotein （HDL） contents increased with the increase in dietary fat level, and they were all the highest in low-protein, high-fat group. The growth performance and serum biochemical parameters of minks were not affected by the interaction between dietary protein and fat levels （P 〉 O. 05 ）. Considering all the factors, when the dietary protein is 32% and the fat level is 20% to 30% under the condition of this experiment, the dietary protein and fat utilization rates are higher, and the male minks during the growing period can get a better growth performance.

The prognostic value of serum C-reactive protein-bound serum amyloid A in early-stage lung cancer

Background:Elevated levels of serum C-reactive protein(CRP) have been reported to have prognostic significance in lung cancer patients.This study aimed to further identify CRP-bound components as prognostic markers for lung cancer and validate their prognostic value.Methods:CRP-bound components obtained from the serum samples from lung cancer patients or healthy controls were analyzed by differential proteomics analysis.CRP-bound serum amyloid A(CRP-SAA) was evaluated by coimmunoprecipitation(IP).Serum samples from two independent cohorts with lung cancer(retrospective cohort,242patients;prospective cohort,222 patients) and healthy controls(159 subjects) were used to evaluate the prognostic value of CRP-SAA by enzyme-linked immunosorbent assay.Results:CRP-SAA was identified specifically in serum samples from lung cancer patients by proteomic analysis.CRP binding to SAA was confirmed by co-IP in serum samples from lung cancer patients and cell culture media.The level of CRP-SAA was significantly higher in patients than in healthy controls(0.37 ± 0.58 vs.0.03 ± 0.04,P < 0.001).Elevated CRP-SAA levels were significantly associated with severe clinical features of lung cancer.The elevation of CRPSAA was associated with lower survival rates for both the retrospective(hazard ration[HR]= 2.181,95%confidence interval[CI]= 1.641-2.897,P < 0.001) and the prospective cohorts(HR = 2.744,95%CI = 1.810-4.161,P < 0.001).Multivariate Cox analysis showed that CRP-SAA was an independent prognostic marker for lung cancer.Remarkably,in stages l-ll patients,only CRP-SAA,not total SAA or CRP,showed significant association with overall survival in two cohorts.Moreover,univariate and multivariate Cox analyses also showed that only CRP-SAA could be used as an independent prognostic marker for early-stage lung cancer patients.Conclusion:CRP-SAA could be a better prognostic marker for lung cancer than total SAA or CRP,especially in earlystage patients.

Acrylamide Alters Cytoskeletal Protein Level in Rat Serum

To study biomarker of acrylamide （ACR） induced neuropathy, Wistar rats received 20 or 40 mg/kg of ACR by ip injection and the levels of light neurofilament （NF-L）, middle NF （NF-M）, heavy NF （NF-H）, β-actin, α-tubulin, and β-tubulin proteins in serum were evaluated using both SDS-PAGE and Western blotting. Compared to controls, NF-L and NF-M decreased,

Correlation of Serum C-Reactive Protein with Disease Severity in Tuberculosis Patients

Purpose: To study the factors influencing sputum smear conversion including Serum C-Reactive Protein (CRP) and its correlation with disease severity in tuberculosis patients. Method: Levels of Serum-CRP concentrations were deter-mined in 60 patients with pulmonary tuberculosis, 30 healthy volunteers and patients in follow-up after completion of antitubercular treatment (DOTS therapy). Results: Serum-CRP levels were found to be significantly higher in smear-positive group as compared with the follow-up patients and smear-negative control group. The values were 43.65 ± 23.68, 9.88 ± 5.23 and 4.04 ± 3.85 mg/L respectively (P Conclusion: Serum-CRP levels are significantly correlated with disease severity in patients with active pulmonary tuberculosis. Thus these findings from the present study would certainly add new criteria for early diagnosis of TB, which may lead to development of new strategies to treat TB.

Correlation between glycated hemoglobin A1c,urinary microalbumin,urinary creatinine,β2 microglobulin,retinol binding protein and diabetic retinopathy

BACKGROUND Retinopathy is the most common microvascular disease of type 2 diabetes,and seriously threatens the life,health and quality of life of patients.It is worth noting that the development of diabetic retinopathy(DR)can be hidden,with few symptoms.Therefore,the preliminary screening of diabetic patients should identify DR as soon as possible,delay disease progression,and play a vital role in its diagnosis and treatment.AIM To investigate the correlation between glycated hemoglobin A1c(HbA1c),urinary microalbumin(U-mALB),urinary creatinine(U-CR),mALB/U-CR ratio,β2 microglobulin(β2MG),retinol binding protein(RBP)and DR.METHODS A total of 180 patients with type 2 diabetes mellitus attending the Second People’s Hospital of Hefei from January 2022 to August 2022 were retrospectively enrolled by ophthalmologists.Based on whether they had combined retinopathy and its degree,68 patients with diabetes mellitus without retinopathy(NDR)were assigned to the NDR group,54 patients with non-proliferative DR(NPDR)to the NPDR group,and 58 patients with proliferative DR to the PDR group.General data,and HbA1c,mALB,β2MG,RBP,mALB/U-CR and U-CR results were collected from the patients and compared among the groups.Pearson's correlation method was used to analyze the correlation between HbA1c,mALB,β2MG,RBP,mALB/U-CR and U-CR indices,and multiple linear regression was applied to identify the risk factors for DR.Receiver operator characteristic(ROC)curves were also drawn.RESULTS The differences in age,gender,systolic and diastolic blood pressure between the groups were not statistically significantly(P>0.05),but the difference in disease duration was statistically significant(P<0.05).The differences in fasting blood glucose,high-density lipoprotein cholesterol,low-density lipoprotein cholesterol,total cholesterol,and triglyceride between the groups were not statistically significant(P>0.05).HbA1c in the PDR group was higher than that in the NPDR and NDR groups(P<0.05).The levels of mALB,β2MG,RBP,mALB/U-CR and UCR in the PDR group were higher than those in the NPDR and NDR groups(P<0.05).Multiple linear regression analysis showed that disease duration,HbA1c,mALB,β2MG,RBP,mALB/U-CR and U-CR were risk factors for the development of DR.The ROC curve showed that the area under the curve(AUC)for the combination of indices(HbA1c+mALB+mALB/U-CR+U-CR+β2MG+RBP)was 0.958,with a sensitivity of 94.83%and specificity of 96.72%,which was higher than the AUC for single index prediction(P<0.05).CONCLUSION HbA1c,mALB,mALB/U-CR,U-CR,β2MG and RBP can reflect the development of DR and are risk factors affecting PDR,and the combination of these six indices has predictive value for PDR.

Application of serum protein electrophoresis in multiple myeloma

Multiple myeloma (MM) is a disease characterized by abnormal proliferation of clonal malignant plasma cells (myeloma cells) in the bone marrow and associated with the increase of monoclonal immunoglobulins (i.e, M-proteins). As the incidence of MM has been increasing year by year, with diverse clinical manifestations, the early diagnosis of MM is of great significance to the subsequent treatment and prognosis. Serum protein electrophoresis (SPE) is the most simple and effective method to isolate protein with the advantages of clear electrophoregram and band, high resolution and good repeatability. It is currently the first choice for the diagnosis of MM. To study the application of SPE to MM can provide a certain reference and help for the preliminary immunophenotyping, diagnosis and efficacy observation of MM.

Serum Proteins Stabilized Calcium Phosphate Nanoparticles and Its Effect on Bel-7402 Cells

Hydroxyapatite has a high affinity to biological macromolecules, especially to proteins. Bovine serum proteins were extracted to be used as stablizer to prepare calcium phosphate nanoparticles . 167.7 nm and 87.7 nm particles were respectively prepared by using bovine serum protein fractions at the concentration of 0. 5 mg/mL and 1.0 mg/mL. As the polysaccharide stabilized hydroxyapatite nanoparticles, the protein-stablized nanoparticles also inhibited the proliferation rate of Bel-7402 cells. It suggested that proteins could be applied to prepare calcium phosphate nanoparticles and it also has the anticaneer effect.

Immunohistochemical Study of Serum Proteins in Normal and Cadmium-Treated Mouse Testis by in vivo Cryotechnique

Objective To investigate time-dependent changes of serum proteins permeability in the normal and cadmium（Cd）-treated mouse testis, reflecting tight junctional （TJ） barriers of Sertoli cells Methods The serum proteins, albumin and immunoglobulin-G（IgG）, in the seminiferous tubules were firstly immobilized by the “in vivo cryotechnique”, in which the dynamic blood circulation was always kept. The cryofixed testicular tissues were then processed for the freeze-substitution method, and embedded in the paraffin wax. Serial sections of 5μm thickness were immunostained by anti-mouse albumin or IgG antibody with peroxidase immunostaining, and also stained with hematoxylin-eosine （HE）for morphological observation. Results In normal seminiferous tubules, albumin immunoreaction products were localized around peritubular myoid cells and among Leydig cells, as well as in blood vessels. They were also localized as arch-like patterns around some spermatogonia in basal compartments. The number of the immunopositive arch structures was different according to developmental stages of the seminiferous cycle, judging from the arrangement of germ cells by HE-staining. The patterns of localization of IgG immunostaining in normal mouse testis were similar to that of albumin. In 24 h after Cd-treatment, some enlarged spaces and vesicular formation in the seminiferous epithelium were observed on the paraffin sections by HE-staining. The albumin or IgGimmunolocalization was seen not only in the basal compartments, but also in the adluminal compartments between Sertoli.cells and germ cells. Conclusion The structural changes of inter-Sertoli TJ barriers in vivo, such as different immunostaining patterns of serum proteins between the normal and Cd-treated mouse seminiferous tubules, could be clearly detected by the “in vivo cryotechnique” with albumin or IgG immunohistochemistry.

Comparison of protein concentrations in serum versus plasma from Alzheimer’s patients

Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The current study provides empirical evidence regarding how blood-based proteins vary depending on whether they are assayed in serum or plasma. Methods: Weanalyzed concentrations of 100 proteins in matched samples of serum and plasma from 39 Caucasian AD participants from the Texas Alzheimer’s Research and Care Consortium bymultiplex immunoassay. Results: Concentrations of 40 proteins were highly correlated (r2≥ 0.75) between plasma and serum while the remaining proteins were moderately to weakly correlated (r2< 0.75). Discussion: Whether plasma vs. serum is assayed can have a large impact on the observed concentration of some proteins, including several proteins that are of great interest to AD pathophysiology. The current findings may explain the significant discrepancies often times reported in the AD biomarker field.

Comparison of the Serum Proteins and Immune Responses of Velogenic Newcastle Disease Virus Infected Chickens and Ducks

The effect of velogenic Newcastle disease virus (vNDV) on the immune responses and serum proteins was investigated in six-week-old ducks and chickens. Results showed that weight loss was markedly significant (p < 0.05) from days 3 - 21 (PI) in chickens and mild (p < 0.05) on days 3 and 15 PI in ducks. The antibody response obtained showed significant (p < 0.05) increase in infected chickens (IC) than those of the infected ducks (ID). While the total serum protein and serum globulin increased significantly (p < 0.05) in IC on days 7 and 14 PI, they decreased significantly (p < 0.05) in ID only on day 21 PI. The immune responses and serum protein values in this experiment X-ray showed less susceptibility of ducks when compared with the chickens. This may be related to marked anorexia and severe dehydration observed in the latter consequent upon serum concentration. Ducks could be maintaining the endemicity of Newcastle disease (ND) as reservoir host.

Comparative evaluation of acute phase proteins by C-reactive protein(CRP)and serum amyloid A(SAA)in nonhuman primates and feline carnivores

The feasibility of a commercially available assay for C-reactive protein(CRP,CRP for humans:hCRP,and CRP for dogs:vCRP)and a trial reagent of serum amyloid A(SAA,vSAA for animals)were applied to the measurement of acute phase proteins in zoo animals,particularly in nonhuman primates and feline carnivores was evaluate.Results showed that hCRP and vSAA methods were applicable to measure CRP and SAA in Haplorhini.There was a highly signifcant correlation between both parameters with remarkably high correlation coefcient.A higher proportion of Bonnet macaques in Haplorhini,and the linear regression with good correlation between hCRP and vSAA levels were observed.Reference values in healthy Bonnet macaques were hCRP(46.86±30.97 nmol/L)and vSAA(9.06±1.95μg/mL).Although Ring-tailed lemur,which belonging to Strepsirrhini,showed low vSAA concentrations(reference values:1.08±0.47μg/mL),vSAA in patients was apparently elevated.The vCRP and vSAA methods were applicable to measurements of CRP and SAA in feline carnivores for highly signifcant correlation between both parameters.Theses two methods were also been deteded in lions,tigers and cheetahs.vSAA assays can be applied to measure SAA levels in other carnivores and herbivores.In conclusion,vSAA systems have potential utility as diagnostic tools for health screening and prediction in zoo animals.

Pressure- and Urea-Induced Denaturation of Bovine Serum Albumin: Considerations about Protein Heterogeneity

Urea denatures proteins at different concentrations, depending on the experimental conditions and the protein. We in-vestigated the pressure-induced denaturation of bovine serum albumin (BSA) in the presence of subdenaturing concen-trations of urea based on a two-state equilibrium. Pressure-induced denaturation was enhanced at urea concentrations ([U]) of 3.5 M to 8.0 M, with the free energy of denaturation at atmospheric pressure ranging from +5.0 to –2.5 kJ/mol of BSA. The m values appeared to be biphasic, with m1 and m2 of 0.92 and 2.35 kJ mol–1?M–1, respectively. Plots of versus ln[U] yielded values of u, the apparent stoichiometric coefficient, of 1.68 and 6.67 mol of urea/mol of BSA for m1 and m2, respectively. These values were compared with the m and u values of other monomeric proteins reported in or calculated from the literature. The very low values of u systematically observed for proteins were suggestive of heterogeneity in the free energy of denaturation. Thus, a u value of 140 mol of urea/mol of BSA may indicate the existence of a heterogeneous molecular population with respect to the free energy of dena-turation.

Effects of Crude Protein Level of Concentrate Supplement on Production Performance and Serum Biochemical Parameters in Post-fattening Hainan Yellow Cattle

[Objective]The paper was to investigate the effects of crude protein level of concentrate supplement on production performance and serum biochemical parameters of post-fattening Hainan Yellow Cattle.[Method]Twelve Hainan Yellow Cattles with the same genetic backgrounds and similar initial weight of(168.13±0.55)kg were randomly divided into three treatments.Cattle were fed with concentrate supplement containing different levels of crude protein.The trial lasted 60 d.[Result]The daily gain of 17.56%crude protein group was significantly higher than those of 15.55%and 13.56%crude protein groups(P<0.05),and the gross profit of 17.56%crude protein group was markedly higher than that of 13.56%crude protein group(P<0.05),but the feed gain ratio of 17.56%crude protein group was significantly lower than that of 13.56%crude protein group(P<0.05).Compared with 15.55%and 13.56%crude protein groups,the serum total protein content markedly increased(P<0.05),but the urea nitrogen level significantly decreased(P<0.05).[Conclusion]When crude protein level of concentrate supplement was 17.56%,post-fattening Hainan Yellow Cattle could obtain better production performance.

Correlation between serum C1q tumor necrosis factor-related protein 4 and high-sensitivity C-reactive protein levels and coronary heart disease

Objective:To investigate the relationship between serum levels of C1q tumor necrosis factorrelated protein 4(CTRP4)and hypersensitive C reactive protein(hs-CRP)and coronary heart disease(CHD)and its clinical value.Methods:128 patients underwent coronary angiography in our hospital,63 males,65 women,Based on blood sugar levels and coronary angiography,Divided into pure coronary heart disease(CHD)group 62 cases,Coronary heart disease with diabetes(DM+CHD)group 66 cases,A total of 126 patients were selected as control group,65 men,61 women,CTRP4 and hs-CRP levels in serum,Using Pearson correlation analysis to assess the correlation between Gennisi score and CTRP4、hs-CRP,Analysis of three groups of biochemical indicators,CTRP4、hs-CRP level changes and clinical significance.Results:The CTRP4、hs-CRP level of DM+CHD group was significantly higher than that of control group and CHD group(P DM+CHD 0.05).The CTRP4、hs-CRP level of the three-vessel coronary artery lesion group in the experimental group was higher than that in the two-vessel lesion group(P﹤0.05),Double branch lesion group was higher than single branch lesion group(P﹤0.05);Correlation analysis shows,There was a significant positive correlation between the CTRP4、hs-CRP level of CHD group and DM+CHD group and the Gennisi score(P DM+CHD 0.05).ROC curves show,CTRP4 and hs-CRP levels had predictive value(CHD group,AUC=0.940,0.934,DM+CHD group,AUC=0.980,0.964),Two associations(CHD:AUC=0.961,P﹤0.001,DM+CHD group:AUCDM+CHD 0.982,P﹤0.001)the predictive value is high.Conclusion:Serum CTRP4 and hs-CRP are positively related to the severity of coronary heart disease,and the sensitivity and specificity of predicting coronary heart disease are high,which is helpful for the identification and early prevention of coronary heart disease,and has certain clinical reference value.