Interpretable CT radiomics model for invasiveness prediction in patients with ground-glass nodules

AIM

To evaluate the performance of an interpretable computed tomography (CT) radiomic model in predicting the invasiveness of ground-glass nodules (GGNs).

MATERIALS AND METHODS

The study was conducted retrospectively from 1 August 2017 to 1 August 2022, at three different centres. Two hundred and thirty patients with GGNs were enrolled at centre I as a training cohort. Centres II (n=157) and III (n=156) formed two external validation cohorts. Radiomics features extracted based on CT were reduced by a coarse-fine feature screening strategy. A radiomic model was developed through the use of the LASSO (least absolute shrinkage and selection operator) and XGBoost algorithms. Then, a radiological model was established through multivariate logistic regression analysis. Finally, the interpretability of the model was explored using SHapley Additive exPlanations (SHAP).

RESULTS

The radiomic XGBoost model outperformed the radiomic logistic model and radiological model in assessing the invasiveness of GGNs. The area under the curve (AUC) values for the radiomic XGBoost model were 0.885 (95% confidence interval [CI] 0.836-0.923), 0.853 (95% CI 0.790-0.906), and 0.838 (95% CI 0.773-0.902) in the training and the two external validation cohorts, respectively. The SHAP method allowed for both a quantitative and visual representation of how decisions were made using a given model for each individual patient. This can provide a deeper understanding of the decision-making mechanisms within the model and the factors that contribute to its prediction effectiveness.

CONCLUSIONS

The present interpretable CT radiomics model has the potential to preoperatively evaluate the invasiveness of GGNs. Furthermore, it can provide personalised, image-based clinical-decision support.

[Risk factors of systemic allergic reactions caused by subcutaneous allergen immunotherapy]

Objective: To investigate the incidence and risk factors of systemic allergic reactions induced by subcutaneous immunotherapy (SCIT) in patients undergoing SCIT injections in Peking Union Medical College Hospital (PUMCH). Methods: This is a single center retrospective cohort study. Using the outpatient information system of PUMCH, the demographic information and injection-related reaction data of patients undergoing SCIT injection in Allergy Department of PUMCH from December 2018 to December 2022 were retrospectively analyzed to count the incidence and risk factors of systemic allergic reactions caused by SCIT. Mann-Whitney nonparametric test or chi-square test was used for single-factor analysis, and multiple logistic regression was used for multiple-factor analysis. Results: A total of 2 897 patients received 18 070 SCIT injections in Allergy Department during the four years, and 40 systemic allergic reactions occurred, with the overall incidence rate of 0.22%. The incidence of systemic allergic reaction was 0.37% when using imported dust mite preparation and 0.15% when using domestic multi-component allergen preparation. The risk factors significantly related with SCIT-induced systemic allergic reactions in patients using imported dust mite preparation were age less than 18 years old (OR=3.186,95%CI: 1.255-8.085), highest injection concentration (OR value could not be calculated because all patients with systemic reactions were injected with highest concentration), and large local reaction in previous injection (OR=22.264,95%CI: 8.205-60.411). The risk factors for SCIT-induced systemic allergic reactions in patients using domestic allergen preparation were 5 or more types of allergens (OR=3.455,95%CI: 1.147-10.402), highest injection concentration (OR=3.794,95%CI: 1.226-11.740) and large local reaction in previous injection (OR=63.577,95%CI: 22.248-181.683). However, SCIT injection in pollen allergic patients during the pollen season did not show a correlation with systemic allergic reaction. Conclusion: The incidence of SCIT-induced systemic allergic reactions was low in the Chinese patient population of this study. Patients with one or more risk factors, such as multiple allergen injection, highest injection concentration, large local reaction in previous injection, should be given high attention and vigilance against systemic allergic reactions.

[Influence of the severity and treatment of allergic rhinitis and asthma on SARS-CoV-2 infection]

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected 660 million people and resulted in 6.7 million deaths. At present, a variety of risk factors related to the severity of COVID-19 have been identified, but whether allergic rhinitis and asthma will affect SARS-CoV-2 infection remains controversial. In general, there is no sufficient evidence to support that allergic rhinitis or asthma is a risk factor for increasing the rate of SARS-CoV-2 infection or aggravating the disease. Some studies even show that atopy may be a protective factor to alleviate SARS-CoV-2 infection, which is related to the decreased expression of angiotensin-converting enzyme 2, the receptor required for SARS-CoV-2 to enter cells, in atopic individuals. This paper reviews the influence of the severity and treatment of allergic rhinitis and asthma on SARS-CoV-2 infection, in order to provide some references for establishing strategies for prevention, risk stratification and treatment of COVID-19.

[Research progress of Eubacterium and its metabolite short-chain fatty acids in regulating type 2 diabetes mellitus]

Intestinal flora and its metabolites are closely related to the progression of type 2 diabetes mellitus(T2DM). Eubacterium is one of the dominant intestinal flora, and its metabolites short-chain fatty acids (SCFAs) play a leading role in regulating intestinal metabolic balance. It has been reported that SCFAs can regulate the secretion of glucagon-like peptide-1, improve the function of pancreatic β cells, participate in bile acids metabolism and regulate the production of inflammatory factors in T2DM. Based on the above research background, this article mainly reviews the relationship between Eubacterium and its metabolite SCFAs and T2DM and its regulatory mechanism.

[Prenatal genetic diagnosis of the fetuses with isolated corpus callosum abnormality]

Objective: To explore the application value of chromosome karyotype analysis, chromosomal microarray analysis (CMA) and whole exome sequencing (WES) in prenatal diagnosis of isolated corpus callosum abnormality (CCA) fetus. Methods: Fetuses diagnosed with isolated CCA by ultrasound and MRI and receiving invasive prenatal diagnosis in Guangzhou Women and Children's Medical Center and Qingyuan People's Hospital from January 2010 to April 2021 were selected. Karyotype analysis and/or CMA [or copy number variation sequencing (CNV-seq)] were performed on all fetal samples, and WES was performed on fetal samples and their parents whose karyotype analysis and/or CMA (or CNV-seq) results were not abnormal. Results: Among 65 fetuses with isolated CCA, 38 cases underwent karyotype analysis, and 3 cases were detected with abnormal karyotypes, with a detection rate of 8% (3/38). A total of 49 fetuses with isolated CCA underwent CMA (or CNV-seq) detection, and 6 cases of pathogenic CNV were detected, the detection rate was 12% (6/49). Among them, the karyotype analysis results were abnormal, and the detection rate of further CMA detection was 1/1. The karyotype results were normal, and the detection rate of further CMA (or CNV-seq) detection was 14% (3/21). The detection rate of CMA as the first-line detection technique was 7% (2/27). A total of 25 fetuses with isolated CCA with negative results of karyotyping and/or CMA were tested by WES, and 9 cases (36%, 9/25) were detected with pathogenic genes. The gradient genetic diagnosis of chromosomal karyotyping, CMA and WES resulted in a definite genetic diagnosis of 26% (17/65) of isolated CCA fetuses. Conclusions: Prenatal genetic diagnosis of isolated CCA fetuses is of great clinical significance. The detection rate of CMA is higher than that of traditional karyotyping. CMA detection could be used as a first-line detection technique for fetuses with isolated CCA. WES could increase the pathogenicity detection rate of fetuses with isolated CCA when karyotype analysis and/or CMA test results are negative.

[Analysis of families with fetal congenital abnormalities but negative prenatal diagnosis by whole exome sequencing]

Objective: To evaluate the value of whole exome sequencing (WES) in prenatal clinical application. Methods: A total of 1 152 cases of congenital abnormal [including structural malformation, nuchal translucency (NT) thickening and intrauterine growth restriction] with traditional prenatal diagnosis [including G-band karyotype analysis and chromosome microarray analysis (CMA)] negative were analyzed. The congenital abnormal fetuses were divided into retrospective group and prospective group according to the time of WES detection, that is whether the pregnancy termination or not. According to the specific location of fetal malformation and their family history, the cohort was divided into subgroups. The clinical prognosis of all fetuses were followed up, and the effect of WES test results on pregnancy decision-making and clinical intervention were analyzed. According to the follow-up results, the data of fetuses with new phenotypes in the third trimester or after birth were re-analyzed. Results: Among 1 152 families who received WES, 5 families were excluded because of nonbiological parents. Among the remaining 1 147 families, 152 fetuses obtained positive diagnosis (13.3%,152/1 147), including 74 fetuses in the retrospective group (16.1%,74/460) and 78 fetuses in the prospective group (11.4%,78/687). In fetuses with negative CMA and G-band karyotype analysis results but new phenotypes in the third trimester or after birth, the positive rate by WES data re-analysis was 4.9% (8/163). A total of 34 (21.3%, 34/160) fetuses were directly affected by the corresponding positive molecular diagnosis. Among 68 cases of live births with diagnostic variation grade 4, 29 cases (42.7%, 29/68) received appropriate medical intervention through rapid review of WES results. Conclusions: WES could increase the detection rate of abnormal fetuses with negative G-banding karyotype analysis and CMA by 13.3%. Prenatal WES could guide pregnancy decision-making and early clinical intervention. It might be an effective strategy to pay attention to the special follow-up of the third trimester and postnatal fetus and to re-analyze the WES data.

[The effect on patient life quality of prophylactic treatment to seasonal allergic rhinitis and related transcriptomics research]

Objective: The preseason prophylactic treatment of seasonal allergic rhinitis (AR) caused by pollens could alleviate AR symptoms during the pollen season. This study aimed to evaluate the effect of prophylaxis usage of suplatast tosilate on the life quality of AR patients in the pollen season, and investigate the potential mechanism of action through transcriptomic analysis. Methods: This is a randomized controlled study. AR patients allergic to weed pollens were recruited from Allergy Clinic of Peking Union Medical College Hospital from January 2020 to June 2020, and divided into prophylactic group who started to take suplatast tosilate as prophylaxis 2 weeks before the spread of weed pollens[n=10, 4 men and 6 women with age range of (34±6) years old] and control group who did not use any prophylactic treatment[n=24, 12 men and 12 women with age range of (33±9) years old]. The differences of age (t=0.381, P=0.706) and gender (χ²=0.595, P=0.715) distribution between the patients of two groups were not statistically significant. All the subjects filled in the rhinoconjunctivitis quality of life questionnaire (RQLQ) while onset of AR symptoms, and peripheral blood was drawn for transcriptomic analysis 1 month before and during the pollen season. Differences between groups were statistically analyzed through chi-square test and t test. Results: There was no significant difference in visual analogue scale of rhinitis symptom in the last pollen season between prophylactic group and control group[ 8.0 (6.4, 9.3) vs 7.3 (6.1, 8.0), Z=1.180, P=0.254]. The RQLQ score of prophylactic group was superior to that of control group in the weed pollen season (2.9±0.9 vs 3.7±0.9, t=-2.438, P=0.026). 210 differentially expressed genes of fold change ≥2 were identified, with 147 genes upregulated and 63 genes downregulated in the prophylactic group compared to the control group. Gene Ontology annotation showed that IL-12 and IL-23 related pathways were downregulated in prophylactic group (P=0.006 48). Polymerase Chain Reaction (PCR) verification of differentially expressed genes indicated that the relative expression level of HLA-G in prophylactic group was significantly lower than that in control group (0.23±0.19 vs 1.00±0.49,t=4.016, P=0.006). Conclusion: The prophylactic treatment of suplatast tosilate showed some benefit to the life quality of seasonal AR patients during the pollen season, and the potential mechanism might be related with the downregulation of IL-12 and IL-23 pathways and decreased expression of HLA-G.

EZH2 regulates the malignancy of human glioblastoma cells via modulation of Twist mRNA stability

Glioblastoma multiforme (GBM) is a lethal primary brain tumor with poor survival lifespan and dismal outcome. However, the effects and mechanisms of epigenetic factors on the development of GBM were still not well illustrated. We found that expression of enhancer of zeste homolog 2 (EZH2), which can catalyze histone H3K27me3 to modulate gene expression, was increased in GBM cells. Knockdown of EZH2 can suppress proliferation and migration, while increase temozolomide (TMZ) sensitivity, of GBM cells. Further, knockdown of EZH2 or its specific inhibitor GSK126 can decrease expression of Twist, while over expression of Twist can reverse si-EZH2-suppressed malignancy of GBM cells. Mechanistically, EZH2 can positively regulate mRNA stability of Twist1 mRNA. Further, miR-206, which can bind with 3'UTR of Twist1 mRNA, was involved in EZH2-regulated mRNA stability of Twist1. Collectively, our data suggest that EZH2 might be a potential target for GBM treatment. Further, miR-206/Twist axis is involved in EZH2-regulated malignancy of GBM cells.

[Appropriate protocol of treatment modulation for seasonal allergic rhinitis caused by cypress pollens]

Objective: To investigate appropriate protocol of treatment modulation for seasonal allergic rhinitis (AR) patients, in order to promote the implementation of personalized medicine. Methods: Total of 124 AR patients allergic to cypress pollens were recruited from January to February 2020 in Department of Allergy in Peking Union Medical College Hospital, 43 males and 81 females with an average age of (41±9) years. The patients were divided into two groups with block randomization method. In the first group, treatment was modulated every two days according to the average daily rhinoconjunctivitis symptom score of the last two days (short-term symptom-score group); while in the second group, therapy regimen was adjusted every week based on the Allergic Rhinitis Control Test (ARCT) score of the last week (long-term ARCT group). The treatment level was up-regulated when the cypress pollen count increased and stayed at a high level (step-up pharmacotherapy stage); and treatment was down-regulated while the pollen count decreased (step-down pharmacotherapy stage). Daily symptom scores, medicine scores, and ARCT scores of the two groups were recorded and compared. Results: During the whole cypress pollen season, the daily rhinoconjunctivitis symptom score of short-term symptom-score group was significantly lower than that in long-term ARCT group(2.4±1.0 vs 2.7±1.0, P<0.01), and the difference between the two groups was more pronounced in the step-up pharmacotherapy stage than that in the step-down pharmacotherapy stage, while there was no statistical difference between the daily medicine scores of the two groups (P>0.05). During the pollen rising period, the ARCT score of short-term symptom-score group was significantly better than that of long-term ARCT group (21(19, 22) vs 20 (17, 21), P=0.049); while in the pollen peak period and decreasing period, the ARCT scores of the two groups showed no statistical difference (P>0.05). The proportion of incompliance with doctor's advice was higher in long-term ARCT group compared to that in short-term symptom-score group (30.1% vs 6.7%, P<0.001). Conclusion: The protocol of treatment modulation for seasonal AR patients allergic to pollens should be developed flexibly according to the variation trend of pollen allergen exposure, so as to implement the idea of personalized medicine.

[The comparison of step-down pharmacotherapy and maintaining dose therapy for seasonal allergic rhinitis]

Objective:There is no standard algorithm for the modulation of pharmacologic treatment of allergic rhinitis. This study aimed to recruited allergic rhinitis patients caused by cypress pollens, and compare the step-down pharmacotherapy guided by pollen count and the maintaining therapy which keeps the previous medicine dose when the pollen count decreased. Method:This was a randomized, open-labelled, parallel control study. During the period after the pollen peak when the cypress pollen count decreased and stayed at a low level, allergic rhinitis patients were randomly divided into two groups. In the step-down group（n=67） medicine dose was reduced, while the maintaining group（n=68） kept taking the same dose as in the peak season. The rhinitis symptom score and medicine score of these two groups were recorded and compared. Result:The daily rhinitis symptom score of the step-down group showed no significant difference with the symptom score of the maintaining group, 2.45±0.32 vs 2.43±0.41, P=0.788. But the medicine score of step-down group（3.67±0.98） was significantly lower than that of maintaining group（4.78±0.70）, P<0.001. The compliance of step-down group（80.6%） was also better than maintaining group（60.3%）, P=0.014. However, in the subgroup of patients with severe rhinitis symptoms, the symptoms of patients taking step-down therapy tended to be more severe than those maintaining the same dose. Conclusion:During the later period of the pollen season when the pollen count was relatively low, the step-down pharmacotherapy guided by pollen count could reduce the medication use, increase the compliance of patients while controlling their rhinitis symptoms effectively. But this strategy might be more suitable for patients with milder symptoms, the severe rhinitis sufferers should be cautious before reducing their medicine dose.

[Analysis of sensitization spectrum and clinical features of children with adenoid hypertrophy and perennial rhinitis]

Objective:To investigate the sensitization spectrum and clinical features of children with adenoid hypertrophy and perennial rhinitis.Method:A total of 121 children with adenoidal hypertrophy and perennial rhinitis were enrolled in the ENT Department of the Children's Hospital of the Capital Institute of Pediatrics and the Allergy Department of Peking Union Medical College Hospital from July to October in 2017. Nasopharyngoscopy was performed, and specific IgE were measured by blood sampling, and the sensitization spectrum and clinical characteristics of the children were analyzed. Result: Adenoid hypertrophy combined with allergic rhinitis accounted for 64.5% of the total, mold sensitization was the most common, accounting for 78.2% of allergic rhinitis patients, including boys accounted for 67.2%, gender differences were statistically significant(P<0.05). Patients with allergic rhinitis had a more severe endoscopic appearance, with a higher proportion of 4 degree, accounting for 75.0% of the total number of children with 4 degree under the nasopharyngoscopy, and only 25.0% of children without defined allergens. There was a significant difference between this two groups(P<0.05). Conclusion: Allergic rhinitis is closely related to adenoid hypertrophy, and the effect of allergen on the clinical manifestations of patients with adenoid hypertrophy should be emphasized.

[The clinical value of China Savin pollen extract used for skin prick test]

Objective:The aim of this study is to evaluate the effectiveness and safety of China Savin pollen extract which was used for skin prick test (SPT) in the diagnosis of China Savin pollen allergy. Method:Patients with diagnosis of allergic diseases were collected from Allergy Department of Peking Union Medical College Hospital. All patients were given SPT with China Savin pollen extract, and the mean wheal diameter (MWD) was measured after 15 minutes. Receiver operating characteristic curve (ROC) analysis was performed based on the results of serum specific immunoglobulin E (sIgE). The effectiveness of SPT in the diagnosis of China Savin pollen allergy was evaluated under different diagnostic cutoff values. Adverse events were also recorded to evaluate the safety. Result:A total of 1 029 patients were enrolled in this study without drop out case. There were 1 007 patients in full analysis set (FAS) and 765 patients in per protocol analysis set (PPS). The elimination rate was 25.66%. The area under the ROC curve of FAS is 0.814 (95%CI: 0.788-0.839); which of PPS is 0.829 (95%CI: 0.801-0.857). Based on the ROC curve of PPS, the optimal and the 95% specificity diagnostic cutoff values of MWD were 3.25 mm and 4.75 mm respectively. Based on different diagnostic cutoff value (3.00, 3.25 and 4.75 mm), the sensitivities of SPT with China Savin pollen extract were 0.740 0 (95%CI: 0.701 6-0.778 4), 0.700 (95%CI: 0.659 8-0.740 2) and 0.532 (95%CI: 0.488 3-0.575 7) respectively, whereas the specificity was gradually increased in sequence, which was 0.769 8 (95%CI: 0.719 1-0.820 5), 0.826 4 (95%CI: 0.780 8-0.872 0) and 0.950 9 (95%CI: 0.924 9-0.976 9) respectively. There were 7 adverse events observed among 6 patients (rate: 0.583%, 6/1 029). The manifestation was mild. There was no severe adverse event. Conclusion:SPT with China Savin pollen extract is an effective and safe tool for the diagnosis of China Savin pollen allergy. The effectiveness of diagnosis could be improved based on integration of medical history and different diagnostic threshold values of SPT.

Continuous Veno-Venous Hemofiltration in the Treatment of Acute Severe Hyponatremia: A Report of 11 Cases

Objectives

To evaluate the treatment effect of continuous veno-venous hemofiltration (CVVH) in patients with acute severe hyponatremia.

Methods

Eleven patients with severe acute hyponatremia, including 6 males and 5 females, aged 25–61 years (mean age 48.36), were treated with CVVH. Hyponatremia occurred 38–48 hours prior to the initiation of CVVH.

Results

All patients tolerated CVVH well, with an average treatment duration of 57.19 (45.6–86) hours. During CVVH, the serum sodium concentration increased significantly from 100.9±3.99 mmol/L at initiation of CVVH to 140.3±1.6 mmol/L after 48 hours of treatment (P<0.01). The serum osmolarity increased concurrently, from 216.7±7.4 mOsm/kgH2O to 295.0±4.2 mOsm/kgH2O (P<0.01). The Glasgow scores and APACHE II scores in these patients improved significantly during treatment.

Conclusions

CVVH is a safe and effective option for the treatment of patients with severe acute hyponatremia due to its slow and continuous nature.

[Effects of double-dose antihistamine or combined therapy in allergic rhinitis]

Objective:To compare the efficacy and side effects of combined therapy with single-dose oral antihistamine and intranasal corticosteroid to monotherapy with double-dose oral antihistamine in the treatment of seasonal allergic rhinitis. Method:Eighty-two patients with seasonal allergic rhinitis caused by cypress pollen were enrolled in a randomized, parallel-group studycomparing 2 weeks therapy of either 10mg oral ebastine plus 200 μg intranasal mometasone furoate once daily (combined group) or 20 mg oral ebastine once daily (double-dose group) during the pollen season. Daily rhinoconjunctivitis symptom score and rescue medication use were recorded in both groups. After the treatment period, questionnaires were used to survey the side effects of medicines and dosage form preference of the patients. The levels of IL-6, IL-8 and TNF-α in the peripheral blood were measured before and after the therapy. Result:During the cypress pollen season, the daily rhinoconjunctivitis symptom score of the combined group (n=42, 3.7±0.4) was significantly lower than that of double-dose group (n=40, 4.5±0.5), P<0.001. The daily rescue medication score of the combined group (1.3±0.6) was also significantly lower than double-dose group(1.7±0.7), P<0.001. The daily medication cost of combined group was 7.08±0.33 Yuan, which was less than that of double-dose group (7.28±0.51 Yuan, P=0.002). There was no statistical difference in the rate of adverse reactions between the two groups. The peripheral levels of IL-6, IL-8 and TNF-α in two groups did not show significant difference at the end of therapy . Conclusion:The combined therapy with single-dose oral antihistamine and intranasal corticosteroid was superior to the monotherapy with double-dose oral antihistamine in the treatment of seasonal allergic rhinitis in our study.

[Treatment effect of sodium pyruvate nasal spray on allergic rhinitis]

Objective:Pyruvate is a key intermediate in several metabolic pathways of human body Sodium pyruvate possesses anti-oxidation and anti-inflammatory effects, which make it a possible novel therapy for allergic rhinitis. However, the relevant clinical research is rare. The aim of the present study is to evaluate the treatment effect of sodium pyruvate nasal spray on allergic rhinitis.Method:This was a randomized, parallel-group, single-center study, and 53 adult patients with seasonal allergic rhinitis caused by Artemisia pollen were recruited. In the pollen season, all the participants were given corticosteroid nasal spray of standard dose for two weeks, and during the next two weeks they were randomized to treatment group (n = 23) taking nasal sodium pyruvate, and control group (n = 30) without sodium pyruvate. Daily rhinoconjunctivitis symptom score and daily rescue medication score were analyzed. Also the fraction of exhaled nitric oxide of the upper airway was measured before and after the treatment of sodium pyruvate. Result:The demographic characteristics and baseline disease severity were not significantly different between the treatment group and control group. Both the daily symptom score (1.4±0.6 vs 1.7±0.4, P= 0.006) and rescue medication score (4.8±1.2 vs 5.8±1.2, P= 0.000) of the treatment group was significantly lower than the scores of control group. In addition, nasal fraction of exhaled nitric oxide of the treatment group (596.3±134.6)ppb tended to be lower than control group (709.6±311.3)ppb, although the difference was not significant, P= 0.408. Conclusion:Sodium pyruvate nasal spray was effective in attenuating the rhinoconjunctivitis symptoms and reducing the rescue medication use of allergic rhinitis patients. The application value and mechanism of action of sodium pyruvate are worth further studying.

Anatomical mechanism of spontaneous recovery in regions caudal to thoracic spinal cord injury lesions in rats

Background

The nerve fibre circuits around a lesion play a major role in the spontaneous recovery process after spinal cord hemisection in rats. The aim of the present study was to answer the following question: in the re-control process, do all spinal cord nerves below the lesion site participate, or do the spinal cord nerves of only one vertebral segment have a role in repair?

Methods

First we made a T7 spinal cord hemisection in 50 rats. Eight weeks later, they were divided into three groups based on distinct second operations at T7: ipsilateral hemisection operation, contralateral hemisection, or transection. We then tested recovery of hindlimbs for another eight weeks. The first step was to confirm the lesion had role or not in the spontaneous recovery process. Secondly, we performed T7 spinal cord hemisections in 125 rats. Eight weeks later, we performed a second single hemisection on the ipsilateral side at T8–T12 and then tested hindlimb recovery for another six weeks.

Results

In the first part, the Basso, Beattie, Bresnahan (BBB) scores and the electrophysiology tests of both hindlimbs weren’t significantly different after the second hemisection of the ipsilateral side. In the second part, the closer the second hemisection was to T12, the more substantial the resulting impairment in BBB score tests and prolonged latency periods.

Conclusions

The nerve regeneration from the lesion area after hemisection has no effect on spontaneous recovery of the spinal cord. Repair is carried out by all vertebrae caudal and ipsilateral to the lesion, with T12 being most important.

2-(3',5'-Dimethoxybenzylidene) cyclopentanone, a novel synthetic small-molecule compound, provides neuroprotective effects against ischemic stroke

2-(3',5'-Dimethoxybenzylidene) cyclopentanone (DMBC) is a novel small-molecule compound synthesized by our group. Here, we found that in rat models of permanent middle cerebral artery occlusion (pMCAO), intraperitoneal injection (ip) of DMBC at 1h after ischemia reduced infarct volume, improved neurological deficits and increased the protein levels of microtubule-associated protein 2 (MAP 2) and glial fibrillary acid protein (GFAP) in the ischemic cortex. Post-treatment of DMBC still produced neuroprotective effects even when administered at 6h after ischemia. In the oxygen-glucose deprivation (OGD)-induced astrocytes or HT22 cell injury, DMBC treatment decreased the OGD-induced lactate dehydrogenase (LDH) leakage and increased the GFAP levels in astrocytes. In addition, Annexin-V-Fluos staining analysis revealed that DMBC treatment attenuated both OGD-induced apoptosis and necrosis in astrocytes. Western blotting analysis showed DMBC treatment inhibited the ischemia or OGD-induced increases in active cathepsin B in the ischemic cortex or in astrocytes or HT22 cells. Immunofluorescence analysis demonstrated that DMBC treatment blocked the ischemia or OGD-induced release of cathepsin B from the lysosomes into the cytoplasm in the ischemic cortex or in astrocytes or HT22 cells. Taken together, our results indicate that DMBC can offer neuroprotective effects against cerebral ischemia with an extended therapeutic window and its mechanism might be associated with inhibition of the cathepsin B activation.

An enhanced cAMP pathway is responsible for the colonic hyper-secretory response to 5-HT in acute stress rats

5-hydroxytryptamine (5-HT) is involved in the stress-induced alteration of colonic functions, specifically motility and secretion, but its precise mechanisms of regulation remain unclear. In the present study, we have investigated the effects of 5-HT on rat colonic mucosal secretion after acute water immersion restraint stress, as well as the underlying mechanism of this phenomenon, using short circuit current recording (I(SC)), real-time polymerase chain reaction, Western blot analysis, and enzyme-linked immunosorbance assays. After 2 h of water immersion restraint stress, the baseline I(SC) and 5-HT-induced I(SC) responses of the colonic mucosa were significantly increased. Pretreatment with selective 5-HT(4) receptor antagonist, SB204070, inhibited the 5-HT-induced colonic I(SC) response by 96 % in normal rats and 91.2 % in acute-stress rats. However, pretreatment with the selective antagonist of 5-HT(3) receptor, MDL72222 or Y-25130, had no obvious effect on 5-HT-induced I(SC) responses under either set of conditions. Total protein expression of both the mucosal 5-HT(3) receptors and the 5-HT(4) receptors underwent no significant changes following acute stress. Both colonic basal cAMP levels and foskolin-induced I(SC) responses were significantly enhanced in acute stress rats. 5-HT significantly enhanced the intracellular cAMP level via 5-HT(4) receptors in the colonic mucosa from both control and stressed animals, and 5-HT-induced cAMP increase in stressed rats was not more than that in control rats. Taken together, the present results indicate that acute water immersion restraint stress enhances colonic secretory responses to 5-HT in rats, a process in which increased cellular cAMP accumulation is involved.

Butyrate promotes the recovering of intestinal wound healing through its positive effect on the tight junctions

Postweaning diarrhea is one of the most common causes of morbidity and mortality in weanling piglets. Feeding sodium butyrate to weanling piglets decreased the incidence of diarrhea, but the mechanism has not been fully elucidated. The present study was to evaluate the effect of sodium butyrate on diarrhea in relation to wound healing of intestinal barrier using IPEC-J2 cell model. Cultured cells were scratched to induce wound and then were treated with 4 mM sodium butyrate. The results showed that supplementation of the cells with sodium butyrate significantly promoted the process of wound healing, indicating the protective effects of butyrate on the intestinal mucosa. Butyrate treatment enhanced mRNA expression of the intestinal mucosal tight junction proteins occludin and zonula occluden protein-1 (P < 0.05), which suggested that the promotion of wound healing by butyrate is related to the maintenance of the function of the intestinal barrier. In addition, in the butyrate-treated group, intestinal total superoxide dismutase and glutathione peroxidase (P < 0.05), two of the main antioxidant enzymes, as well as glutathione (P < 0.05), one of the nonenzymatic antioxidant components, were enhanced whereas the malondialdehyde level, a marker of free radical mediated lipid peroxidation injury, was decreased (P < 0.05) compared with the control group. Collectively, these results indicate that dietary sodium butyrate might, at least partly, play an important role in recovering the intestinal tight junctions having a positive effect on maintaining the gut integrity.

Nonlinear interaction of voluntary breathing and cardiovascular regulation

To investigate the effects of voluntary breathing on respiratory sinus arrhythmia and nonlinearity of heart rate variability (HRV), two kinds of voluntary breathing, speech and breath-holding, were used. The results showed that both types of voluntary breathing diminished the high frequency component of HRV, but speech decreased, while breath-holding enhanced the nonlinearity of HRV as detected by the Volterra series method. This finding indicates that respiratory patterns have a variety of influences on cardiovascular regulation.

The cyclophosphamide metabolite, acrolein, induces cytoskeletal changes and oxidative stress in Sertoli cells

The aim of this study is to explore the mechanism by which acrolein (ACR), a metabolite of cyclophosphamide (CP), induces immature Sertoli cell cytoskeletal changes. Sertoli cells obtained from rats were cultivated and treated with 50 and 100 μM ACR. XTT assays were performed to detect cell viability. Activities of superoxide dismutase (SOD), glutathione peroxidases (GSH-Px), and catalase (CAT), as well as total anti-oxidation competence (T-AOC) were examined. Superoxide anion levels were detected by a fluorescent probe. Cell ultrastructure changes were observed by transmission fluorescent microscope. Actin filament (F-actin) distribution was detected by immunofluorescence, and ERK and p38MAPK expression were detected by western blot analysis. ACR significantly decreased the viability of Sertoli cells in a dose- and time-dependent manner. T-AOC and the antioxidant activity of SOD, CAT and GSH-Px, were decreased in ACR-treated groups compared with the control group. The levels of reactive oxygen species (ROS) in ACR-treated Sertoli cells were increased. In addition, characteristics of cell apoptosis such as mitochondrial swelling, aggregated chromatin, condensed cytoplasm, nuclei splitting, and nuclei vacuolization were observed in ACR-treated cells. Furthermore, ACR-treatment also induced microfilament aggregation, marginalization and regionalization. The expression levels of ERK and p38MAPK were also increased in ACR-treated cells in a dose- and time-dependent manner. ACR, a major CP metabolite, impairs the cytoskeleton which is likely caused by induction of the oxidative stress response through up-regulation of ERK and p38MAPK expression.

Clinical characteristics and prognosis of diffuse proliferative lupus nephritis with thrombotic microangiopathy

We retrospectively analyzed the clinicopathologic characteristics and prognosis of 33 patients with diffuse proliferative lupus nephritis (class IV LN) complicated with thrombotic microangiopathy (TMA). Eighty-one percent of patients had renal dysfunction (mean Scr 3.1 ± 2.0 mg/dl), among whom 42.4% needed acute hemodialysis. Nephrotic proteinuria, gross hematuria and hypertension were presented in 57.6%, 24.2% and 93.9% of the patients. Microangiopathic hemolytic anemia, serum anti-dsDNA and anticardiolipin antibodies were found in 60.6%, 75.8% and 33.3% of the patients. Renal biopsy showed IV-G in 75.8%, class IV with class V in 21.2%, and IV-S in 1.23% of the patients. Glomerular segmental necrosis, microthrombi, crescents and arteriolar thrombosis were found in 51.5%, 69.7%, 60.6% and 60.7% of the patients, respectively. The follow up was 1 to 101 months (median 13 months). Only 50% of patients showed response to treatment. Three patients died, 10 developed end-stage renal failure (ESRF). The 5-year patient and renal survival rate was 69.2% and 46.7%, respectively. Major risks for ESRF included: a need for acute dialysis on admission, no response to the treatment and high renal chronic index. The results showed that class IV lupus nephritis with TMA has high mortality and low renal survival.

Activation of submucosal 5-HT(3) receptors elicits a somatostatin-dependent inhibition of ion secretion in rat colon

BACKGROUND AND PURPOSE

5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT(3) receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect.

EXPERIMENTAL APPROACH

Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current (I(sc)) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay (elisa). Immunohistochemical techniques were used to study the expression of 5-HT(3) receptors, somatostatin and somatostatin receptors in colonic tissue.

KEY RESULTS

In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT(3) receptor antagonists enhanced 5-HT-induced increases in I(sc). However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT(3) receptor antagonists inhibited 5-HT-induced DeltaI(sc). Pretreatment with a somatostatin-2 (sst(2)) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced DeltaI(sc). Combination of sst(2) and 5-HT(3) receptor antagonists did not cause further enhancement of 5-HT-induced DeltaI(sc). Moreover, both sst(2) and 5-HT(3) receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT(3) receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT(3) receptors on submucosal somatostatin neurons and of sst(2) receptors on colonic mucosa.

CONCLUSION AND IMPLICATIONS

Activation of neuronal 5-HT(3) receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons.

Clinicopathological characteristics of familial SLE patients with lupus nephritis

This study aimed to analyze the clinicopathological characteristics of familial SLE patients with lupus nephritis (LN). A total of 136 Chinese patients with lupus nephritis diagnosed by renal biopsy, including 34 familial patients and 102 sporadic cases, were recruited. Their demographic information, age of onset, disease duration, clinical features, laboratory data and histological manifestations were compared. The first-degree relatives (17 sibling cases and eight parent-offspring cases) of familial SLE patients were primarily affected. The prevalence of fever, rash and arthritis in familial subjects was higher than that in sporadic subjects. Familial patients had lower platelet counts and higher low-density lipoprotein. In familial patients, class V lupus nephritis was less common. After adjusted with the Benjamini and Hochberg procedure, however, fever was the only feature occurring significantly and more frequently in familial patients (58.8% vs 26.5%, P = 0.001). Moreover, SLEDAI and other clinicopathological features did not differ significantly between the two groups. Multivariate analysis showed that a higher prevalence of fever was an independent predictor of familial SLE. Most clinicopathological features in familial SLE patients were not significantly different from those in sporadic patients; the severity of LN in familial SLE patients was similar to that of sporadic cases. Thus, familial SLE may not be a different clinical entity.

Paired box 6 (PAX6) regulates glucose metabolism via proinsulin processing mediated by prohormone convertase 1/3 (PC1/3)

AIMS/HYPOTHESIS

Human patients with aniridia caused by heterozygous PAX6 mutations display abnormal glucose metabolism, but the underlying molecular mechanism is largely unknown. Disturbed islet architecture has been proposed as the reason why mice with complete inactivation of paired box 6 (PAX6) in the pancreas develop diabetes. This is not, however, the case in human aniridia patients with heterozygous PAX6 deficiency and no apparent defects in pancreatic development. We investigated the molecular mechanism underlying the development of abnormal glucose metabolism in these patients.

METHODS

A human aniridia pedigree with a PAX6 R240Stop mutation was examined for abnormal glucose metabolism using an OGTT. The underlying mechanism was further investigated using Pax6 R266Stop mutant small-eye mice, which also have abnormal glucose metabolism similar to that in PAX6 R240Stop mutation human aniridia patients.

RESULTS

Paired box 6 (PAX6) deficiency, both in aniridia patients with a heterozygous PAX6 R240Stop mutation and in mice with a heterozygous Pax6 R266Stop mutation, causes defective proinsulin processing and abnormal glucose metabolism. PAX6 can bind to the promoter and directly upregulate production of prohormone convertase (PC)1/3, an enzyme essential for conversion of proinsulin to insulin. Pax6 mutations lead to PC1/3 deficiency, resulting in defective proinsulin processing and abnormal glucose metabolism.

CONCLUSIONS/INTERPRETATION

This study indicates a novel function for PAX6 in the regulation of proinsulin processing and glucose metabolism via modulation of PC1/3 production. It also provides an insight into the abnormal glucose metabolism caused by heterozygous PAX6 mutations in humans and mice.

Circulating thrombomodulin and vascular cell adhesion molecule-1 and renal vascular lesion in patients with lupus nephritis

Currently, the detection of renal vascular lesions (VLS) in lupus nephritis (LN) mainly depends on biopsy examination, and lack surrogate biomarkers for clinical dynamic evaluation. The aim of the present study is to explore the correlation between circulatory endothelial damage biomarkers and VLS. Soluble E-selectin, thrombomodulin (TM) and vascular cell adhesion molecule-1 (VCAM-1) were measured by ELISA. TM and VCAM-1 levels both were significantly elevated in LN with VLS than in LN without VLS (P < 0.01). However, the serum E-selectin was not significantly changed in LN patients with and without VLS. A positive correlation was found between TM and serum creatinine (r = 0.617, P < 0.05) in patients with vascular lesions. In order to further analyse the relationship between TM level and severity degree of vascular lesions in LN patients, we subdivided the patients with vascular lesions into two groups: with thrombotic microangiopathy (TMA) and without TMA. TM level of the patients with TMA is significantly higher than those without TMA (P < 0.01). In conclusion, combined with renal pathological examination, monitoring the circulatory levels of TM and VCAM-1, can provide circulating biomarkers of VLS in LN patients.

Amylin deposition in the kidney of patients with diabetic nephropathy

Amylin (islet amyloid peptide) plays a critical role in islet amyloidosis and in the development of beta-cell dysfunction in patients with diabetes; however, the involvement of amylin in renal amyloidosis has not been studied. For this reason, we surveyed 149 patients with biopsy-proven diabetic nephropathy (DN). The results were compared to 95 renal disease control patients, which included membranoproliferative glomerulonephritis, light-chain deposition, IgA nephropathy, and obesity-related glomerulopathy (ORG). Seventy-two of the 149 patients with DN showed amylin deposition in their renal tissue. Amylin was mainly distributed in the expanded mesangial area, Kimmelstiel-Wilson nodules, Bowman's capsule, and in blood vessels. The frequencies of mesangial proliferation, glomerular nodule lesions, and glomerular sclerosis were higher in DN patients with amylin deposits. Furthermore, the tubular interstitial lesions were more severe in these patients. Of the 95 disease-control patients, four with ORG were positive for renal amylin deposits. Our study has found renal amylin deposition in patients with DN and that the deposition was associated with disease severity. We suggest that strict metabolic control and reversing insulin resistance in patients with diabetes may blunt the process of amylin deposition in the kidney and possibly protect renal function in these patients.

Association of interleukin-10 gene -592 A/C polymorphism with the clinical and pathological diversity of lupus nephritis

OBJECTIVE

To investigate the interleukin-10 (IL-10) gene -592 A/C polymorphism in Chinese patients with lupus nephritis (LN) and evaluate the role of lL-10 in the pathogenesis and clinical/pathological diversity of LN.

METHODS

Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analyses were used to detect the IL-10 gene -592 A/C polymorphism in 265 LN patients and 100 ethnically matched controls. Frequencies of the genotypes were compared between LN patients and controls and among LN patients with different pathological classes. The clinical and pathological characteristics of the patients with different genotypes were also analyzed. Serum IL-10 levels of the patients were determined by ELISA.

RESULTS

No significant differences were found in the distribution of the polymorphism between healthy controls and LN patients. The parameters of disease activity index (DAI), percentage of positive serum anti-dsDNA antibodies, proteinuria and hematuria, and frequency of glomerular thrombi were all higher in patients with -592 AC/CC genotypes than those with AA genotype. AC/CC genotypes were more frequent in patients with LN-IV than in those with LN-II and Va. There was no significant difference in the serum IL-10 levels in patients with these three genotypes.

CONCLUSION

The IL-10 gene -592 A/C polymorphism appears to be associated with disease activity and renal pathology of LN, but not associated with LN susceptibility or serum IL-10 levels. Patients carrying the -592 C allele had a higher risk of diffuse proliferative glomerulonephritis, indicating the genetic influence of the IL-10 gene polymorphism in the renal lesions of LN.

C4d-positive acute humoral renal allograft rejection: Rescue therapy by immunoadsorption in combination with tacrolimus and mycophenolate mofetil

OBJECTIVE

We investigated the efficacy of immunoadsorption (IA) in combination with tacrolimus (FK506) and mycophenolate mofetil (MMF) rescue therapy for C4d-positive acute humoral rejection (AHR) of renal transplants.

METHODS

Six of 185 cadaveric renal allograft recipients developed AHR at a mean of 4.8 +/- 0.8 days after the operation. C4d deposits were observed in peritubular capillaries (PTC) with accumulation of granulocytes. IA with staphylococcal protein A and FK506-MMF combination therapy were administered.

RESULTS

After treatment with IA for 6.3 +/- 1.03 sessions combined with FK506 (0.14 to 0.16 mg.kg(-1).d(-1)) and MMF (1.5 g/d) therapy, renal function recovered in all the patients. The mean duration of treatment to a serum creatinine decrease was 14 +/- 2.9 days. The pre-IA panel reactive antibody reactivity (PRA) peaked at 50.2% +/- 6.1%, and was significantly reduced to 8.3% +/- 2.9% after IA. In four of six patients repeat allograft biopsy revealed a remission of AHR. With a mean follow-up of 18.8 +/- 5.46 months, patient and allograft survival are 100% and renal function remains stable with a mean serum creatinine of 1.2 +/- 0.22 mg/dL.

CONCLUSION

The optimal treatment for alloantibody-mediated AHR remains uncertain. Our findings suggest that a therapeutic approach combining IA and FK506-MMF rescue improves the outcome of AHR.

Emodin ameliorates glucose-induced morphologic abnormalities and synthesis of transforming growth factor beta1 and fibronectin by human peritoneal mesothelial cells

OBJECTIVE

Excessive synthesis and deposition of matrix proteins by peritoneal mesothelial cells can lead to structural and functional changes in the peritoneal membrane, jeopardizing the long-term efficacy of peritoneal dialysis (PD). Prolonged exposure to high glucose concentrations in PD fluid has been implicated as a major stimulus to matrix accumulation, through the induction of transforming growth factor beta1 (TGFbeta1). This study investigated the effect of emodin (3-methyl-1,6,8-trihydroxyanthraquinone) on TGFbeta1 and fibronectin (FN) synthesis in human peritoneal mesothelial cells (HPMCs) under high glucose concentration.

DESIGN

The HPMCs were preconditioned in either 5 mmol/L or 30 mmol/L D-glucose for 2 weeks prior to the addition of emodin. Cell viability was assessed by MTT assay and lactate dehydrogenase (LDH) release. Morphology of HPMCs was studied by phase-contrast microscopy. Modulation of TGFbeta1 and FN synthesis at transcription and translation were investigated by reverse transcriptase polymerase chain reaction (RT-PCR), ELISA, and Western blot analysis.

RESULTS

When cultured under 30 mmol/L D-glucose, HPMCs demonstrated increased cell volume, multinucleation, and denudation of the monolayer, as compared with cells cultured under a physiologic (5 mmol/L) glucose concentration. High glucose concentration induced TGFbeta1 synthesis by HPMCs (217.17 +/- 14.88 pg/mL at 5 mmol/L D-glucose vs 370.33 +/- 20.67 pg/mL at 30 mmol/L D-glucose, p < 0.0001), and FN synthesis was induced at transcription and translation. Mannitol at 30 mmol/L did not affect HPMC morphology; matrix synthesis was also unaltered. Administration of emodin together with 30 mmol/L D-glucose resulted in amelioration of cell enlargement and exfoliation, and abrogation of TGFbeta1 induction (370.33 +/- 20.67 pg/mL for 30 mmol/L D-glucose alone vs 260.50 +/- 17.89 pg/mL for 30 mmol/L D-glucose + emodin, p < 0.0001). Synthesis of FN induced by high glucose was also reduced by 40% in the presence of emodin.

CONCLUSIONS

These findings provide the first evidence that emodin can ameliorate high glucose-induced matrix synthesis in HPMCs by suppression of TGFbeta1. Emodin may thus be useful in preserving peritoneal integrity in PD.

Rhein inhibits renal tubular epithelial cell hypertrophy and extracellular matrix accumulation induced by transforming growth factor beta1

AIM

To investigate the effects of rhein on cell hypertrophy and accumulation of extracellular matrix (ECM) in the renal tubular epithelial cells.

METHODS

LLC-PK1 cells were incubated with transforming growth factor beta1 (TGFbeta1) 2 microg/L for 24 h to induce cell hypertrophy and production of ECM. To evaluate the effects of rhein on inhibiting the action of TGFbeta1, cell volume, cellular protein level, and [3H]leucine incorporation in LLC-PK1 cells treated with rhein at different concentrations were measured. In addition, the [3H]proline incorporation, level of fibronectin (FN) in supernatant, and mRNA expression of collagen IV and FN were also detected in rhein treated cells.

RESULTS

The cell volume, cellular protein content, and [3H]leucine incorporation were markedly increased in LLC-PK1 cells after TGFbeta1 stimulation as compared with control (P < 0.01), and this TGFbeta1-stimulated cell hypertrophy was ameliorated by rhein. It was observed that TGFbeta1 not only increased the production of FN and [3H]proline incorporation in LLC-PK1 cells (P < 0.01), but also enhanced the mRNA expression of collagen IV and FN. Rhein significantly decreased the protein production and mRNA expression of ECM in LLC-PK1 cells stimulated by TGFbeta1.

CONCLUSION

Rhein can inhibit cell hypertrophy and ECM accumulation in LLC-PK1 cells induced by TGFbeta1, which may partly account for the role of rhein in preventing and retarding the progression of diabetic nephropathy.

Toxic effects of six plant oils alone and in combination with controlled atmosphere on Liposcelis bostrychophila (Psocoptera: Liposcelididae)

Six plant essential oils alone as repellent and fumigant, and in combination with the controlled atmosphere against Liposcelis bostrychophila Badonnel were assessed in the laboratory. These essential oils were extracted from the leaves of six source plants: Citrus tangerina Tanaka, Citrus aurantium L., Citrus bergamia Risso et Poiteau, Pinus sylvestris L., Cupressus funebris End]., and Eucalyptus citriodora Hook. The repellency test indicated that L. bostrychophila adults were repelled by filter paper strips treated with six essential oils. Of these essential oils, the C. funebris oil was most effective followed by that of F. sylvestris, C. tangerina, C. bergamia, and E. citriodora. The average repellency of the C. aurantium oil against L. bostrychophila adults was significantly lower than other five test oils by day 14. These essential oils had a high level of toxicity in the fumigation assay against L. bostrychophila adults at both 10 and 20 ppm. When combined with two controlled atmosphere treatments (12% CO2 + 9% O2, and 10% CO2 + 5% O2, balanced N2), the toxicity of plant oils was enhanced significantly.

[Effect of organic solvents on DNA conformation by fluorescent probe method]

In this paper, the conformation of calf thymus DNA(DNA) is investigated in some common solvents by spectrofluorimetry. The result of fluorescence spectra and scatchard plot indicate that the binding constant between DNA and ethidium bromide (EB) will decrease with the increasing concentration of ethanol, and the number of binding sites will increase. The change of binding constant elucidate that the interaction between DNA and EB will become poor, and the change of binding sites shows that the conformation of DNA has transformed from B-form to A-form. In the course of this change, the distance between both neighboring base plan will be decreased. When the EB molecule just fit into the interval, the fluorescence intensity will be maximum. When DNA shrink further, the EB molecules will be excluded from DNA, then the fluorescence intensity will decrease. Although the conformation of DNA will be changed in organic solvents, it will not denaturate or dehelix, because the absorption of DNA will not increase greatly with the increasing concentration of ethanol. The melting temperature of DNA decreases continually as the weight fraction of ethanol concentration is increased. It shows that the DNA will be more distabilized in ethanol, so it helps to explain some phenomena of life and physiology. Meanwhile, the results offer an opportunity to further study the interaction DNA and insoluble drugs.

[Determination of salicin in extract of willow bark by high performance liquid chromatography]

An HPLC method for the determination of salicin in extract of willow bark is described. Chromatographic analysis was carried out on a Kromasil C18, 5 microns column(4.6 mm i.d. x 250 mm) with methanol-0.01 mol/L KH2PO4 buffer (pH 4.01) (15:85, volume ratio) as mobile phase. The detection wavelength was 265 nm. Salicin was extracted from samples with methanol-water(50:50, volume ratio), and centrifuged. Ten microL of supernatant were injected. The average recoveries were from 96.1% to 101.2% (n = 5), and the relative standard deviation (RSD) was 1.43%. The method is simple, rapid and accurate.

Intracerebral haemorrhage and Qigong

We report on a 65-year-old woman who presented with acute right-sided weakness because of an intracerebral (thalamic) haemorrhage. As a Qigong enthusiast with a long-standing history of hypertension, she developed a stroke syndrome soon after practising Qigong one morning. Following neurological recovery, the patient exhibited erratic blood pressure responses while practising Qigong, despite the fact that resting blood pressure was normal. The haemodynamic responses to exercise are discussed and a review of the therapeutic implications of practising Qigong is presented.

Triptolide inhibits vascular endothelial growth factor expression and production in endothelial cells

AIM

To investigate the effects of triptolide on vascular endothelial growth factor (VEGF) expression and secretion by endothelial cells, and explore the mechanism of anti-proteinuric effect of triptolide on glomerulonephritis.

METHODS

A human umbilical endothelium derived cell line (ECV-304) from American Type Culture Collection (ATCC) was used in this study. The effects of triptolide on VEGF mRNA expression, production, and secretion induced by 12-o-tetradecanoyl-phorbol-13-acetate (TPA) were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), flow cytometry, and enzyme linked immunosorbent assay (ELISA) respectively. The endothelial c-fos/c-jun mRNA expression were also detected by RT-PCR after treatment of triptolide.

RESULTS

VEGF mRNA expression was markedly up-regulated by TPA-stimulation. In addition, the production and secretion of VEGF in endothelial cells also increased in TPA treated cells. It was founded that triptolide inhibited VEGF mRNA expression, protein production and secretion in endothelial cells induced by TPA. Interestingly, TPA-induced c-fos/c-jun mRNA expression in endothelial cells was also inhibited by triptolide.

CONCLUSION

Triptolide is a potent inhibitor of VEGF expression and production in endothelial cells. The inhibitory effects of triptolide on VEGF expression and production can contribute to its anti-proteinuric effect on glomerulonephritis. Down-regulation of c-fos/c-jun expression in endothelial cells by triptolide is one of the mechanisms of the inhibitory effect of triptolide on VEGF expression.

Oral stereognosis in stroke and Parkinson's disease: a comparison of partially dentate and edentulous individuals

Oral stereognosis was measured in partially dentate and edentulous patients with stroke, Parkinson's disease, and an age and gender-matched control group. Stereognostic tests involving conventional free intra-oral manipulation of test objects were undertaken in the partially dentate and edentulous with and without complete dentures. Comparisons were made using the unpaired t-test and ANOVA. Edentulous stroke patients without dentures had significantly greater error scores and fewer correct identifications compared with partially dentate stroke patients. Stereognostic measures were similar in the partially dentate and edentulous with dentures, within experimental groups. In the partially dentate, there were no differences in stereognostic measures between the three groups. Stereognostic measures were poorer in edentulous stroke patients with and without dentures compared with the edentulous control group. Partially dentate stroke patients are less likely to have impaired oral stereognosis than edentulous stroke patients.

Effect on human attention of exposure to the electromagnetic field emitted by mobile phones

This study examined the effect of exposure to the electromagnetic field emitted by mobile phones on human attention. Three measures of attention were administered to 72 teenagers, 37 of whom were mobile phone users. The results showed that the mobile phone users performed better on one of the three measures of attention than did the non-mobile phone users. The results suggest that exposure to the electromagnetic field emitted by mobile phones may have a mild facilitating effect on attention functions, which is consistent with previous observations that exposure to the electromagnetic field has a facilitating effect on cognitive processing. The possibility that mobile phone users may be naturally better at multiple tasking tasks was discussed.

A phospholipase C inhibitor, phenylmethylsulfonyl fluoride, ameliorates ischemic injury to brain mitochondria in rats

AIM

To study the effect of phenylmethylsulfonyl fluoride (PMSF), a phospholipase C inhibitor, on ischemic injury to brain mitochondria in rats.

METHODS

The phospholipid level, membrane fluidity, and respiratory control ratio of brain mitochondria were measured. The effect of phenylmethylsulfonyl fluoride was tested.

RESULTS

The phospholipid level, membrane fluidity, and respiratory control ratio of brain mitochondria in ischemia group decreased but increased in the PMSF treatment group (P < 0.05).

CONCLUSION

PMSF ameliorated ischemic injury to brain mitochondria in rats.

Glucose transporter in human glomerular mesangial cells modulated by transforming growth factor-beta and rhein

AIM

To identify GLUT1 in human mesangial cells and its regulation by TGF-beta1 and rhein.

METHODS

Identification of GLUT1 was performed in human mesangial cells by analyzing its mRNA expression, protein product, and functional assay. The effects of TGF-beta1 and rhein on glucose uptake and GLUT1 mRNA expression in mesangial cells were examined by [3H]-2-deoxy-D-glucose uptake and Northern blotting analysis.

RESULTS

It was found that human mesangial cells do express functional GLUT1. The 2-DOG uptake of mesangial cells was markedly increased by TGF-beta1 stimulation with simultaneous elevated expression of GLUT1 mRNA. Increased glucose uptake and GLUT1 mRNA expression in mesangial cells induced by TGF-beta1 were markedly attenuated by rhein in a dose-dependent manner.

CONCLUSION

We found that functional GLUT1 did present in human mesangial cells. TGF-beta1 stimulated the glucose uptake in mesangial cells through upregulation of GLUT1 expression, this effect of TGF-beta1 could be antagonized by rhein.

Comparison of photovoltaic behaviors for horseradish peroxidase and its mimicry by surface photovoltage spectroscopy

Surface photovoltage spectroscopy (SPS) was chosen to study the photovoltaic behavior of horseradish peroxidase (HRP), hemin and immobilized hemin (poly(NIPAAm/MBA/hemin)). Different photovoltaic behaviors were observed in these three systems. In air, similar SPS curves were found for HRP and poly(NIPAAm/MBA/hemin) with different response intensities. However, poly(NIPAAm/MBA/hemin) showed a wider changing range upon increasing the positive and negative bias to 1.0 V. The SPS of hemin showed a total different behavior when an external positive potential was applied. In vacuum, clearly different photovoltaic behaviors were found. Moreover, the response value decreased when HRP was exposed to O2, the SPS intensity was different from that in air, and could be altered by changing the external biases. On the other hand, the SPS could not be changed before and after poly(NIPAAm/MBA/hemin) was exposed to O2. These differences may result from different chemical microenvironments for hemin in HRP versus that in poly(NIPAAm/MBA/hemin). It could be concluded that H2O and O2 were important factors affecting the photovoltage response in HRP, but only H2O played this important role in poly(NIPAAm/MBA/hemin).

Long-term outcome of acute renal injury induced by Aristolochia manshuriensis Kom in rats

AIM

To investigate the long-term functional and morphological changes of the kidney induced by acute intoxication of Aristolochia manshuriensis Kom in rats.

METHODS

Experimental model of acute renal injury was established in the Sprague-Dawley rats with oral administration of decoctions of Chinese herb, Aristolochia manshuriensis Kom, at dosages of 50 g.kg-1.d-1 and 30 g.kg-1.d-1 for 7 consecutive days, and 20 g.kg-1.d-1 for 15 consecutive days. Renal function was assayed at months 0 (right after treatment), 1, 3, and 6 of the experiment. Renal histological examination was also performed.

RESULTS

1) At month 0, the renal functional changes of acute renal injury included azotemia, low molecular weight proteinuria, glycosuria, hypoosmotic urine, and NAG enzymuria. Histopathological changes showed acute tubular necrosis, predominantly at the corticomedullary junction. 2) At months 1 and 3, the renal function of rats of the experiment was gradually restored and histopathologic examination suggested that the tubular lesions gradually recovered. In HE sections, basophilic deposits were observed in the tubular cytoplasm. And interstitial infiltration of inflammatory cells was not prominent. 3) At months 6, renal preneoplastic lesions, renal tumors, and extrarenal tumors occurred in rats. The occurrence of renal preneoplastic lesions at dosages of 50 g.kg-1.d-1, 30 g.kg-1.d-1, and 20 g.kg-1.d-1 were 100.0% at all three doses, renal tumors 42.8%, 25.0%, and 0%, respectively, extrarenal tumors 14.4%, 12.5%, and 12.5%, respectively, and systemic tumors 57.2%, 37.5%, and 12.5%, respectively. The occurrence of basophilic deposits, renal preneoplastic lesions, renal tumors, and extrarenal tumors in normal control group was nil.

CONCLUSIONS

1) Administration of large dosage of Aristolochia manshuriensis Kom induces acute renal failure in rats. 2) The long-term renal function and histopathologic changes of acute renal injury induced by Aristolochia manshuriensis Komrecover spontaneously. 3) Aristolochia manshuriensis Kom has been proved to be oncogenic for the first time.

Triptolide: a potent inhibitor of NF-kappa B in T-lymphocytes

AIM

To study the effect of triptolide on the activity of nuclear factor-kappa B (NF-kappa B) and gene expression of I kappa B alpha, a major inhibitor of NF-kappa B, in human Jurkat T cell line.

METHODS

Jurkat cells treated with or without PMA/PHA were incubated with varied doses of triptolide for different time periods. The activity of NF-kappa B in Jurkat cells was measured with electrophoretic mobility shift assays (EMSA), and the mRNA expression of I kappa B alpha in Jurkat cells was detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

PMA/PHA treatment was found to induce NF-kappa B activation rapidly. Triptolide treatment decreased the activity of NF-kappa B in both PMA/PHA treated and untreated Jurkat cells. This effect of triptolide was in a dose-dependent manner and was more obvious in cells treated with PMA/PHA. The mRNA expression of I kappa B alpha were upregulated by triptolide, while this effect was more potent in cells without PMA/PHA treatment.

CONCLUSION

Triptolide is a potent inhibitor of NF-kappa B activation in T lymphocyte and this effect is partly due to the upregulation of I kappa B alpha mRNA expression.