Increased Tuberculosis Reactivation Risk in Patients Receiving Immune Checkpoint Inhibitor-Based Therapy.

OBJECTIVE: Reports of tuberculosis (TB) during anticancer treatment with immune checkpoint inhibitors (ICIs) are increasing. However, it is not clear whether the use of ICIs is a significant risk factor for TB, including reactivation or latent TB infection (LTBI). METHODS: To determine the risk of TB reactivation in patients with lung cancer who use ICIs or tyrosine kinase inhibitors (TKIs), we conducted a retrospective study using a hospital-based cancer registry. In addition, we monitored patients with cancer using ICI or TKI in a multicenter prospective study to check the incidence of LTBI. RESULTS: In the retrospective study, several demographic factors were imbalanced between the ICI and TKI groups: the ICI group was younger, had more males, exhibited more squamous cell carcinoma in histology rather than adenocarcinoma, had fewer EGFR mutations, and received more chemotherapy. Propensity score matching was used to control for confounding factors, and we found that the incidence of TB was higher among patients with lung cancer who received ICIs than among those who received TKIs (2298 vs 412 per 100 000 person-years, P = .0165). Through multivariable analysis, group (ICI vs TKI) was the independent risk factor for TB development (adjusted hazard ratio (aHR): 6.29, 95% CI, 1.23-32.09, P = .0269). In the prospective cohort, which included 72 patients receiving ICIs and 50 receiving TKIs, we found that the incidence of positive seroconversion of LTBI by interferon gamma release assay (IGRA) was significantly higher in patients receiving ICIs (18% vs 0%, aHR: 9.88, P = 0.035) under multivariable Cox regression. CONCLUSION: The use of ICIs may be linked to a higher likelihood of TB reactivation and LTBI than individuals solely receiving TKIs as anticancer therapy. Consequently, the implementation of a screening program for TB reactivation and LTBI among patients undergoing ICI treatment could prove advantageous by enabling early detection and prompt treatment of the infection.

[Solid Tumors With Cold Agglutinins:Report of Two Cases and Literature Review].

Cold agglutinins(CA),autoantibodies against the antigen I or i on the surface of red blood cells,are mainly of IgM class,and the majority have κ light chains.They can lead to red blood cell agglutination at decreased body temperature and are usually associated with infections,drug reactions,autoimmune diseases,and hematological malignancies.However,solid tumors with CA are rare.We reported two cases of CA in the peripheral blood of patients with solid tumors.Peripheral complete blood cell count of the patients at admission showed reduced erythrocyte count and hematocrit,mismatching between erythrocyte count and hemoglobin,abnormally elevated levels of mean corpuscular hemoglobin and mean cell hemoglobin concentration.Peripheral blood smear showed erythrocyte aggregation.After the sample was preheated at 37 ℃ for 30 min,the reversibility of red blood cell aggregation was observed,and the erythrocyte parameters were corrected.

Curative efficacy of low frequency electrical stimulation in preventing urinary retention after cervical cancer operation.

BACKGROUND: To evaluate the clinical significance of low-frequency electrical stimulation in preventing urinary retention after radical hysterectomy. METHODS: A total of 91 women with stage IA2-IB2 cervical cancer, who were treated with radical hysterectomy and lymphadenectomy from January 2009 to December 2012, were enrolled into this study and were randomly divided into two groups: trail group (48 cases) and control group (43 cases). Traditional bladder function training and low-frequency electrical stimulation were conducted in the trail group, while patients in the control group were only treated by traditional bladder training. The general condition, rate of urinary retention, and muscle strength grades of pelvic floor muscle in the perioperative period were compared between these two groups. RESULTS: The incidence of postoperative urinary retention in the electrical stimulation group was 10.41%, significantly lower than that in the control group (44.18%), and the difference was statistically significant (P < 0.01). The duration of postoperative fever and use of antibiotics were almost the same between these two groups. Eleven days after surgery, the difference in grades of the pelvic floor muscle between these two groups was not statistically significant. However, 14 days after the operation, grades of the pelvic floor muscle were significantly higher in the trail group than in the control group, and the difference was statistically significant (P < 0.01). In addition, although there was no significant difference between the two groups with different parameters (P = 0.782), the incidence of urinary retention was lower in the endorphins analgesia program group than in the neuromuscular repair program group (9.09% < 11.54%). CONCLUSION: Low-frequency electrical stimulation is more effective than conventional intervention in preventing urinary retention after radical hysterectomy. It also intensifies the recovery of pelvic muscle strength.

Erythropoietin promoted the proliferation of hepatocellular carcinoma through hypoxia induced translocation of its specific receptor.

BACKGROUND: Erythropoietin (EPO) is a hypoxia-inducible stimulator of erythropoiesis. Besides its traditional application in anemia therapy, it offers an effective treatment in the cancer patients, especially those who receive chemotherapy. Several reports indicated that it could promote the tumor cell proliferation through its specific receptor (EPOR). Unfortunately, the role of EPO/EPOR in hepatocellular carcinoma (HCC) progressing is still uncertain. METHODS: Protein in tumor tissue from HCC patients or H22 tumor-bearing mice was detected with immunohistochemistry. Cells were cultured under 1% oxygen to establish hypoxia. RT-PCR and western blotting were used to measure mRNA and protein of EPO/EPOR, respectively. MTT, flow cytometry and PCNA staining were used to detect cell proliferation. Immunofluorescence staining was applied to study the expression and location of cellular EPOR. The EPOR binding studies were performed with 125I-EPO radiolabeling assay. RESULTS: EPO and EPOR protein were up-regulated in HCC tissue of patients and H22-bearing mice. These were positively correlated with hypoxia-inducible factor -1 α and ki-67. Hypoxia up-regulated the expression of EPO and EPOR in HepG2 cells. It also induced the proliferation and increased the percentage of divided cells after 24, 48 and 72 h treatment. These were inhibited in cells pre-treated with 0.5 µg/mL soluble-EPOR. Immunofluorescence staining presented that EPOR was obviously translocated from nucleus to cytoplasm and membrane under hypoxia. EPOR binding activity was also increased after exposure to hypoxia. Recombinant human erythropoietin obviously elevated cell proliferation rate and the percentage of divided under hypoxia but not normoxia, which were also inhibited by soluble-EPOR. CONCLUSIONS: Our result indicated for the first time that EPO promoted the proliferation of HCC cells through hypoxia induced translocation of it specific receptor. Trial registration TJC20141113, retrospectively registered.

A novel method for evaluating load restraint assemblies to ensure the safety of railway freight transportation.

The violent goods vibration during curve negotiation is a huge threat to the vehicle running safety. Qualified load restraint assemblies that can significantly suppress the cargo vibration are necessary. This study proposes a novel method for evaluating the essential restraint strength, focusing on the relative motion between cargo and wagon. In the beginning, as a comparison, current methods are used to calculate the necessary stiffness of lashings, which are adopted to restrain the cargo vibration on the wagon. Based on the data of the field test, the accuracy of the established wagon-cargo coupled dynamics model is validated. The loaded wagon model negotiates the curve under different running and loading conditions. The simulation results and analysis demonstrate effective strategies for suppressing the vibration of the cargo and reveal the necessary lashing stiffness. The comparison among the results of different evaluation methods shows that the stability of the cargo can be improved by optimizing the lashing stiffness with the method of dynamics simulations. We hope this study will make a positive contribution to the safety of railway freight transportation.

Association of preschool children behavior and emotional problems with the parenting behavior of both parents.

BACKGROUND: Parental behaviors are key in shaping children's psychological and behavioral development, crucial for early identification and prevention of mental health issues, reducing psychological trauma in childhood. AIM: To investigate the relationship between parenting behaviors and behavioral and emotional issues in preschool children. METHODS: From October 2017 to May 2018, 7 kindergartens in Ma'anshan City were selected to conduct a parent self-filled questionnaire - Health Development Survey of Preschool Children. Children's Strength and Difficulties Questionnaire (Parent Version) was applied to measures the children's behavioral and emotional performance. Parenting behavior was evaluated using the Parental Behavior Inventory. Binomial logistic regression model was used to analyze the association between the detection rate of preschool children's behavior and emotional problems and their parenting behaviors. RESULTS: High level of parental support/participation was negatively correlated with conduct problems, abnormal hyperactivity, abnormal total difficulty scores and abnormal prosocial behavior problems. High level of maternal support/participation was negatively correlated with abnormal emotional symptoms and abnormal peer interaction in children. High level of parental hostility/coercion was positively correlated with abnormal emotional symptoms, abnormal conduct problems, abnormal hyperactivity, abnormal peer interaction, and abnormal total difficulty scores in children (all P < 0.05). Moreover, paternal parenting behaviors had similarly effects on behavior and emotional problems of preschool children compared with maternal parenting behaviors (all P > 0.05), after calculating ratio of odds ratio values. CONCLUSION: Our study found that parenting behaviors are associated with behavioral and emotional issues in preschool children. Overall, the more supportive or involved the parents are, the fewer behavioral and emotional problems the children experience; conversely, the more hostile or controlling the parents are, the more behavioral and emotional problems the children face. Moreover, the impact of fathers' parenting behaviors on preschool children's behavior and emotions is no less significant than that of mothers' parenting behaviors.

[Study on concomitant surgical correction of pelvic organ prolapse and TVT-O for treatment of stress urinary incontinence].

OBJECTIVE: To investigate the necessity, safety and efficacy of transobturator tension-free vaginal tape (TVT-O) for treatment of stress urinary incontinence (SUI) during transvaginal corrective operation of pelvic organ prolapse (POP). METHODS: From Jan. 2005 to Dec. 2010, 92 patients undergoing transvaginal pelvic reconstruction surgery for correction of POP concomitant TVT-O for treatment of SUI in Department of Obstetrics and Gynecology affiliated to Beijing Chaoyang Hospital as concomitant surgery group were enrolled in this retrospective study matched with 90 patients with mild SUI without SUI surgery as non-concomitant surgery group and 120 patients without SUI as control group.Variable clinical index, clinical efficacy and complications were compared among those three groups. RESULTS: Compared with those in the other two groups, the mean age [(62 ± 11) years] was lower (P = 0.007,0.038), the operation time only slightly increased (12.8 min and 12.9 min respectively) significantly in concomitant TVT-O group. The bleeding loss and the length of staying hospital after operation all exhibited no significant differences within three groups (P > 0.05). The effective rate for SUI was 96.7% (89/92) in concomitant TVT-O group, corrective operation of POP was ineffective for 74.4% (67/90) SUI, 9.2% (11/120) patients presented new SUI in the patients without SUI preoperatively. CONCLUSIONS: TVT-O is a simple, safe and effective method in the treatment of SUI, which is more suitable for performing simultaneously during the corrective operation of POP.Efficacy of SUI correction was limited in those patients undergoing only pelvic reconstructive surgery. However, a preventive anti-incontinence procedure is not recommended because of the lower incidence in POP patients without SUI preoperatively.

[Association between parental MTHFR gene polymorphism 677C/T and nonsyndromic cleft lip and palate in offspring].

OBJECTIVE: To explore the association between parental genetic polymorphism of methylenetetrahydrofolate reductase (MTHFR) 677C/T and occurrence of nonsyndromic cleft lip with or without cleft palate (NSCL/P) in offspring in Shandong Province. METHODS: MTHFR genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Parents of 89 NSCL/P patients treated at Qilu Hospital from August, 2006 to August, 2008 and those of 64 healthy children were recruited in this case-control study. RESULTS: Frequencies of T and C alleles in mothers of patients and healthy children were 65.73% and 46.09%, and 34.27% and 53.91%, respectively (Chi-square=13.663, P<0.01). Offspring whose mothers had T alleles were 2.243 times more likely to develop NSCL/P (95%CI: 1.408-3.572). Frequencies of T and C alleles in fathers of patients and healthy children were 62.92% and 55.47%, and 37.08% and 44.53%, respectively (Chi-square=2.222, P>0.05). The chance for parents of the patient and control groups to bear an affected fetus carrying homozygous mutations were 43% and 29%, respectively (P>0.05). CONCLUSION: In Shandong Province, maternal genotype for the MTHFR 677C/T polymorphism has a significant impact on the occurrence of NSCL/P in their offspring, whilst paternal genotype for this polymorphism may not be a risk factor for NSCL/P in their offspring.

The Impact of Nontuberculous Mycobacteria Species on Mortality in Patients With Nontuberculous Mycobacterial Lung Disease.

Patients with nontuberculous mycobacterial lung disease (NTM-LD) have increased mortality. The impact of NTM species on the risk of mortality remains unclear, especially that of death by non-cancer causes. We conducted a retrospective cohort study from 2006 to 2018 in a tertiary-care hospital in Taiwan. We enrolled patients who fulfilled the microbiological diagnostic criteria of NTM-LD. The mortality causes within 8 years after diagnosis were identified, and the Cox proportional hazard regression was performed for risk factors of mortality. A total of 1,652 subjects with NTM-LD were included. Among them, 723 (43.8%) were infected by Mycobacterium avium complex (MAC), 408 (24.7%) by M. abscessus complex (MABC), 120 (7.3%) by Mycobacterium kansasii (MK), 304 (18.4%) by other rapid-growing mycobacteria (RGM), and 97 (5.9%) by other slow-growing mycobacteria (SGM) groups. The 8-year all-cause mortality was 45.2% for all and the highest in the MK-LD group (59.2%), followed by the MABC-LD and MAC-LD groups. The adjusted hazard ratios were 2.20 (95% confidence interval: 1.40-3.46) in the MK-LD, 1.85 (1.54-2.22) in the MABC-LD, and 1.65 (1.12-2.41) in the MAC-LD groups for all-cause mortality, compared with the SGM group. Kaplan-Meier survival curves showed that all-cause mortality, non-cancer mortality, and mortality due to chronic airway diseases were significantly correlated with NTM species (log-rank p = 0.0031, < 0.001, and 0.001, respectively). High 8-year mortality rates were found in patients with NTM-LDs according to different NTM species. Notably, the difference was significant in non-cancer mortality causes, especially in chronic airway diseases.

GPX4 Plays a Crucial Role in Fuzheng Kang'ai Decoction-Induced Non-Small Cell Lung Cancer Cell Ferroptosis.

Background: Fuzheng Kang'ai decoction (FZKA) has been widely used to treat Non-Small Cell Lung Cancer (NSCLC) patients in China for decades, showing definitively curative effects in clinic. Recently, we found that FZKA could induce NSCLC cell ferroptosis, another type of programmed cell death (PCD), which is totally different from cell apoptosis. Therefore, in the present study, we aim to discover the exact mechanism by which FZKA induces NSCLC cell ferroptosis, which is rarely studied in Traditional Chinese Medicine (TCM). Methods: Cell proliferation assay were performed to detect the cell viability. Cell ferroptosis triggered by FZKA was observed by performing lipid peroxidation assay, Fe2+ Ions assay, and mitochondrial ultrastructure by transmission electron microscopy. Ferroptosis inhibitors including liproxstatin-1 and UAMC 3203 were used to block ferroptosis. The ratio of GSH/GSSG was done to measure the alteration of oxidative stress. Western blot and qRT-PCR were carried out to detect the expression of solute carrier family 7 member 11 (SLC7A11), solute carrier family 3 member 2 (SLC3A2) and glutathione peroxidase 4 (GPX4) at protein and mRNA levels, respectively. Lentivirus transfection was performed to overexpress GPX4 stably. Animal model was done to verify the effect of FZKA-induced ferroptosis in NSCLC in vivo and immunohistochemistry was done to detect the expression of SLC7A11, SLC3A2 and GPX4 at protein level. Results: First of all, in vitro experiments confirmed the inhibition effect of FZKA on NSCLC cell growth. We then, for the first time, found that FZKA induced NSCLC cell ferroptosis by increasing lipid peroxidation and cellular Fe2+ Ions. Moreover, characteristic morphological changes of NSCLC cell ferroptosis was observed under transmission electron microscopy. Mechanistically, GPX4, as a key inhibitor of lipid peroxidation, was greatly suppressed by FZKA treatment both at protein and mRNA levels. Furthermore, system xc- (SLC7A11 and SLC3A2) were found to be suppressed and a decreased GSH/GSSG ratio was observed at the same time when treated with FZKA. Notably, overexpressing GPX4 reversed the effect of FZKA-induced NSCLC cell ferroptosis significantly. Finally, the above effect was validated using animal model in vivo. Conclusion: Our findings conclude that GPX4 plays a crucial role in FZKA-induced NSCLC cell ferroptosis, providing a novel molecular mechanism by which FZKA treats NSCLC.

ABCB1 gene polymorphisms are associated with the severity of major depressive disorder and its response to escitalopram treatment.

OBJECTIVE: ATP-binding cassette, sub-family B (MDR/TAP), member 1 (ABCB1) is a drug transporter protein expressed on the epithelial cells of the intestine and the endothelial cells of the blood-brain barrier. Intestinal ABCB1 actively transports drugs from the cell membrane and prevents them from entering the blood stream whereas the blood-brain barrier ABCB1 prevents drugs from entering the central nervous system. In this study, we tested whether genetic polymorphisms within the ABCB1 gene are associated with the severity of depression and the effectiveness of the antidepressant, escitalopram (S-CIT), in treating major depressive disorder (MDD). METHODS: Twenty single nucleotide polymorphisms in the ABCB1 gene were selected and genotyped in 100 MDD patients who had undergone S-CIT treatment continuously for 8 weeks. The serum concentrations of S-CIT and its metabolites (S-desmethylcitalopram and S-didesmethylcitalopram) were then measured at weeks 2, 4, and 8. RESULTS: The ABCB1 genotypes of rs1922242 (P=0.0028) and rs1202184 (P=0.0021) showed significant association with the severity of depressive symptoms as assessed by the Hamilton Rating Scale for Depression adjusted with Hamilton Rating Scale for Anxiety. The haplotype block, rs1882478-rs2235048-rs2235047-rs1045642-rs6949448 (from intron 27 to intron 26), of ABCB1 was found strongly associated with the remission rate (global P=0.003, d.f.=69) in which haplotype T-T-T-C-C was associated with a slower remission rate on S-CIT treatment (P=0.001). The haplotypes may not be indicators of the severity of depression or anxiety. CONCLUSION: Our findings suggest that single nucleotide polymorphisms in the ABCB1 gene may be indicators of the severity of depression and of the likely S-CIT treatment remission response in MDD.

Optimization-Based Model Fitting for Latent Class and Latent Profile Analyses.

Statisticians typically estimate the parameters of latent class and latent profile models using the Expectation-Maximization algorithm. This paper proposes an alternative two-stage approach to model fitting. The first stage uses the modified k-means and hierarchical clustering algorithms to identify the latent classes that best satisfy the conditional independence assumption underlying the latent variable model. The second stage then uses mixture modeling treating the class membership as known. The proposed approach is theoretically justifiable, directly checks the conditional independence assumption, and converges much faster than the full likelihood approach when analyzing high-dimensional data. This paper also develops a new classification rule based on latent variable models. The proposed classification procedure reduces the dimensionality of measured data and explicitly recognizes the heterogeneous nature of the complex disease, which makes it perfect for analyzing high-throughput genomic data. Simulation studies and real data analysis demonstrate the advantages of the proposed method.

Long-Term Effect of Early Post-operative Transcutaneous Electrical Stimulation on Voiding Function After Radical Hysterectomy: A Multicenter, Randomized, Controlled Trial.

Introduction: Post-radical-hysterectomy (RH) patients suffer from a series of problems resulting from neurovascular injury, such as bladder dysfunction, which reduce their quality of life. We have designed this study to evaluate the efficacy of transcutaneous electrical stimulation (TENS) on patient rehabilitation after RH for early cervical cancer. Materials and methods: A total of 97 patients were enrolled in a randomized-controlled trial (from January 2015 to December 2019) involving 7 medical centers nationwide. Patients were assigned to either the intervention group (n = 46), or the control group (n = 51). TENS was given to patients in the intervention group from the 7th day after surgery for a total of 14-21 days. The control group received no TENS. Primary outcomes were measured for residual urine volume and recovery of urination function. Secondary outcomes were measures for urodynamics (UDS), pelvic floor electromyography function examination (PFEmF), and quality of life (QoL). Results: Residual urine volume and improvement in the rate of urination were found to show no significant differences on the 14th, 21st, and 28th days after surgery. The maximum flow rate (Qmax) in the intervention group was significantly higher than that in the control group on the 28th day, but there were no significant differences in average flow rate, voiding time, time to Qmax, muscle fiber strength, muscle fiber fatigue, and the abnormal rate of A3 reflection on the 28th day and the 3rd mo., as well as in the QoL at 3rd mo., 6th mo., and 12th mo. after surgery. Conclusion: Our study showed no sufficient evidence to prove that TENS under the trialed parameters could improve the subject's voiding function, PFEmF, and QOL after RH. This has provided valuable data for rehabilitation after RH. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02492542.

[Relationship between cathepsin L and invasion and metastasis of ovarian carcinoma cells].

OBJECTIVE: To clone cathepsin L (CTSL) gene and construct the eukaryotic expression plasmid pcDNA3.1-CTSL and study the relationship between CTSL and invasion and metastasis in ovarian cancer cells in vitro. METHODS: The total RNA was extracted from the ovarian cancer tissue and the intact cDNA of CTSL was applied by reverse transcription (RT)-PCR. The product of RT-PCR was cloned to pMD18-T vector, and subcloned to pcDNA3.1 vector. It was tested by the enzymation and DNA sequencing. The eukaryotic expression plasmid of CTSL was introduced into HO8910 cells by liposome transfection reagent. RT-PCR was used to confirm the recombinant plasmid DNA integrated with the genomic DNA of HO8910 cells. Western blot was used to confirm the CTSL protein expression in positive clones cells. The cell growth curves, clonogenicity efficiency were observed. The cell cycles were measured by flow cytometer. The ability of invasion, metastasis and adhesion of ovarian cancer cells were detected by the matrigel invasion assay, transwell migration assay and adhesion assay, respectively. RESULTS: The results from restrictive enzyme analysis and sequencing showed that the CTSL gene was successfully inserted into pcDNA3.1. Result from RT-PCR and western blot showed that the ovarian cancer cells which transfected by recombinant plasmid could express CTSL gene and protein. There was no difference between HO8910-CTSL and HO8910-pcDNA3.1 cells in proliferation and adhesion ability (0.16 ± 0.04 versus 0.19 ± 0.04) of the cells (P > 0.05). There was difference between HO8910-CTSL and HO8910-pcDNA3.1 cells in matrigel invasion ability (0.34 ± 0.18 versus 0.17 ± 0.04) and metastasis ability (1.252 ± 0.114 versus 0.486 ± 0.027) of cancer (all P < 0.05). CONCLUSION: CTSL maybe increase the ability of invasion and metastasis of ovarian cancer cells in vitro, which may be a molecular target of blocking invasion and metastasis of ovarian cancer.

Sixty-eight cases of child chronic cough treated by moxibustion.

OBJECTIVE: To observe the therapeutic effects of moxibustion for chronic cough in children. METHODS: 68 child cases of chronic cough were treated by moxibustion. RESULTS: 54 cases were cured, 13 cases improved, and one case failed. The cure rate was 79.2%, with a total effective rate of 98.5%. CONCLUSION: The moxibustion therapy has definite therapeutic effect for children chronic cough.

[Immune resonance scattering spectral analysis of fenvalerate].

In the pH 7.2 Na2HPO4-NaH2PO4 buffer solutions and in the presence of PEG-6000, fenvalerate (Fen) antisera was combined with Fen specifically, and aggregated to form immune complex particles that exhibited five resonance scattering peaks at 350, 390, 420, 440 and 480 nm respectively. The peak at 390 nm was the strongest and was chosen for use. Fen concentration (c) in the range of 0.20 to 6.40 microg x mL(-1) was proportional to the resonance scattering intensity at 390 nm. Its regression equation was DeltaIRS 23.05c-1.39, the correlation coefficient was 0.9978, and the detection limit was 0.07 microg x mL(-1). Effects of buffer solution type, pH value, buffer solution volume, fenvalerate antisera concentration, PEG-6000 concentration, incubation temperature and time on the resonance scattering intensity were considered in detail. With pH (5.8-8.0) increasing, the IRS and Ib all decreased. When the pH value was at 7.2, the DeltaIRS was bigger. Three buffer solutions of pH 7.2, including Na2HPO4-citric acid, Na2HPO4-KH2PO4 and Na2HPO4-NaH2PO4, were examined. The pH 7.2 Na2HPO4-NaH2PO4 buffer solution gives the biggest DeltaIRS value. PEG-6000 could enhance the DeltaIRS value. When the concentration of PEG-6000 was 50.0 mg x mL(-1), the DeltaIRS was achieved at max. Fen was a stable chemical. The IRS increased within 20 min,while the DeltaIRS remained constant when incubation time was in the range of 20-40 min. The condition of a pH 7.2 Na2HPO4-NaH2PO4 buffer solution-50.0 mg x mL(-1) PEG-6000-6.67 microg x mL(-1) Fen antisera-30 degrees C-incubation time 20 min was chosen. According to the procedure, the influence of foreign substances on the determination of 1.60 microg x mL(-1) Fen was examined, within a relative error of +/- 5%. Results showed that the following coexistent substances had no impact on the RS assay: 96 microg x mL(-1) ametryne, 96 microg x mL(-1) m-aminotoluene, 48 microg x mL(-1) simetryne, 48 microg x mL(-1) p-aminotoluene,80 microg x mL(-1) BSA, 80 microg x mL(-1) HSA, 80 microg x mL(-1) Fe3+, 80 microg x mL(-1) Mg2+, 160 microg x mL(-1) Ca2+, and 160 microg x mL(-1) glucose. The results indicated that this RSS assay has good selectivity. This immune resonance scattering spectral assay was applied to the determination of Fen in waste water samples with satisfactory results. The recovery was in the range of 92.91%-101.25%, and the relative standard deviation was in the range of 1.71%-4.80%.

Arachidonic acid induces both Na+ and Ca2+ entry resulting in apoptosis.

Marked accumulation of arachidonic acid (AA) and intracellular Ca2+ and Na+ overloads are seen during brain ischemia. In this study, we show that, in neurons, AA induces cytosolic Na+ ([Na+](cyt)) and Ca2+ ([Ca2+](cyt)) overload via a non-selective cation conductance (NSCC), resulting in mitochondrial [Na+](m) and [Ca2+](m) overload. Another two types of free fatty acids, including oleic acid and eicosapentaenoic acid, induced a smaller increase in the [Ca2+](i) and [Na+](i). RU360, a selective inhibitor of the mitochondrial Ca2+ uniporter, inhibited the AA-induced [Ca2+](m) and [Na+](m) overload, but not the [Ca2+](cyt) and [Na+](cyt) overload. The [Na+](m) overload was also markedly inhibited by either Ca2+-free medium or CGP3715, a selective inhibitor of the mitochondrial Na+(cyt)-Ca2+(m) exchanger. Moreover, RU360, Ca2+-free medium, Na+-free medium, or cyclosporin A (CsA) largely prevented AA-induced opening of the mitochondrial permeability transition pore, cytochrome c release, and caspase 3-dependent neuronal apoptosis. Importantly, Na+-ionophore/Ca2+-free medium, which induced [Na+](m) overload, but not [Ca2+](m) overload, also caused cyclosporin A-sensitive mitochondrial permeability transition pore opening, resulting in caspase 3-dependent apoptosis, indicating that [Na+](m) overload per se induced apoptosis. Our results therefore suggest that AA-induced [Na+](m) overload, acting via activation of the NSCC, is an important upstream signal in the mitochondrial-mediated apoptotic pathway. The NSCC may therefore act as a potential neuronal death pore which is activated by AA accumulation under pathological conditions.

[Immunoresonance scattering spectral assay of complement factor 4(C4)].

Based on resonance scattering (RS) effect of immune complex particles, a new resonance scattering method for the determination of C4 in the human blood serum was developed. It was based on the fact that goat anti-human C4 was combined with complement factor 4 (C4) in the pH 7.3 Na2 HPO4-KH2PO4 buffer solution. It is known that antibody has C-terminal and N-terminal, and the N-terminal is the binding site of antigen and it could combine with antigen. Because the stereo structure anastomoses and the charge is opposite between goat ant-human C4 and C4, they could attract and combine with each other. The attraction and combination have high idiosyncrasy and they are done by Van der Waals force, hydrophobic force, Coulomb attracting force and hydrogen bond binding force, and form immune complex particles that exhibit three resonance scattering peaks at 350, 390 and 440 nm, respectively, in the presence of PEG-6000. The laser scattering results indicate that the average diameter of the immune complex particles is about 3 440.0 nm. The influence of pH, goat anti-human C4 and PEG-6000 concentration, incubation temperature and incubation time, foreign substance such as arginine, -phenyl alanine, L-glutamic acid, L-cystine, L-threonine, L-tryptophan, L-histidine, L-leucine, glucose, EDTA, human serum albumin (HSA), bovine serum albumin (BSA), L-proline, L-lysine on the determination of C4 was considered in details. Under the conditions chosen, C4 concentration in the range from 0.18 to 2.60 microg x mL(-1) is proportional to the resonance scattering intensity at 350 and 390 nm. Its regression equation is deltaI350 nm = 28.23c + 9.17 and deltaI390 nm = 31.36c + 11.08, the correlation coefficient is 0.993 9 and 0.992 3, and the detection limit is 0.084 microg x mL(-1) and 0.11 microg x mL(-1), respectively. The method has been applied to the determination of C4 in the human blood serum, and the results are in agreement with that of the immunoturbidity, with relative standard deviation of 1.88%-4.36%, and with some advantages including simplicity, rapidity, high sensitivity and selectivity.

[Resonance scattering spectral properties of CdTe nanoparticles and its application].

In the present paper, CdTe quantum dots were prepared, and the resonance scattering, fluorescence and absorption spectral properties of CdTe quantum dots in aqueous solution were studied in details. The fluorescence spectral results showed that the CdTe quantum dots of 3.8, 4.0 and 4.6 nm in diameter have fluorescence peaks at 601, 625 and 654 nm, respectively, the fluorescence peak (lambda F) red shifts, and the fluorescence intensity is proportional to the CdTe concentration. The linear relationship was found between the fluorescence peak wavelength and the logarithm of the diameter. The relationships was lambda F = 126.74 ln(d) + 395.92, with a related coefficient of 0.9945. For CdTe quantum dots of 3.8 nm in size, the fluorescence intensity at 601 nm was proportional to the concentration in the range of 11.25-540 micromol x L(-1). The regression equation is F601 nm = 0.7223c + 3.28, with a correlation coefficient of 0.9980. The absorption spectral results showed that the CdTe quantum dots of 3.8, 4.0 and 4.6 nm in diameter have absorption peak at 550, 573 and 590 nm, respectively. The absorption value is proportional to CdTe quantum dots concentration. For CdTe quantum dots of 3.8 nm in size, the concentration in the range of 11.25-180.0 micromol x L(-1) obeys Lamb-Beer's law. The absorption peak (lambda A) also red shifted and widened, absorption value decreased with the diameter (d). The linear relationship was found between the absorption peak wavelength and the logarithm of the diameter. The relationships was lambda A = 155.01 ln(d) + 415.52, with a related coefficient of 0.9956. The resonance scattering (RS) spectra showed that the CdTe quantum dots of 3.8, 4.0, 4.6, 4.8, 5.2, 6.5 and 8.6 nm in diameter have resonance scattering peaks at 597.94, 622.02, 645.94, 654.05, 656.95, 700.98, 735 nm respectively. The RS peak wavelength lambda R is also proportional to the logarithm of the diameter of CdTe quantum dots. Its regression equation is lambda R = 148.37 ln(d) + 418.08 and the correlation coefficient is 0.9952. For CdTe quantum dots with the same diameter such as 3.8 nm, the resonance scattering intensity at 597 nm is proportional to the CdTe concentration. The linear range is 22.5-180.0 micromol x L(-1), the regression equation is I597 nm = 0.5721c + 5.884, and the correlation coefficient is 0.9975. A new resonance scattering method was applied to the determination of the diameter of CdTe quantum dots, with the advantages of simplicity, quick operation and good practical values.