[Development and validation of risk prediction model for new-onset cardiovascular diseases among breast cancer patients: Based on regional medical data of Inner Mongolia].

OBJECTIVE: To develop and validate a three-year risk prediction model for new-onset cardiovascular diseases (CVD) among female patients with breast cancer. METHODS: Based on the data from Inner Mongolia Regional Healthcare Information Platform, female breast cancer patients over 18 years old who had received anti-tumor treatments were included. The candidate predictors were selected by Lasso regression after being included according to the results of the multivariate Fine & Gray model. Cox proportional hazard model, Logistic regression model, Fine & Gray model, random forest model, and XGBoost model were trained on the training set, and the model performance was evaluated on the testing set. The discrimination was evaluated by the area under the curve (AUC) of the receiver operator characteristic curve (ROC), and the calibration was evaluated by the calibration curve. RESULTS: A total of 19 325 breast cancer patients were identified, with an average age of (52.76±10.44) years. The median follow-up was 1.18 [interquartile range (IQR): 2.71] years. In the study, 7 856 patients (40.65%) developed CVD within 3 years after the diagnosis of breast cancer. The final selected variables included age at diagnosis of breast cancer, gross domestic product (GDP) of residence, tumor stage, history of hypertension, ischemic heart disease, and cerebrovascular disease, type of surgery, type of chemotherapy and radiotherapy. In terms of model discrimination, when not considering survival time, the AUC of the XGBoost model was significantly higher than that of the random forest model [0.660 (95%CI: 0.644-0.675) vs. 0.608 (95%CI: 0.591-0.624), P < 0.001] and Logistic regression model [0.609 (95%CI: 0.593-0.625), P < 0.001]. The Logistic regression model and the XGBoost model showed better calibration. When considering survival time, Cox proportional hazard model and Fine & Gray model showed no significant difference for AUC [0.600 (95%CI: 0.584-0.616) vs. 0.615 (95%CI: 0.599-0.631), P=0.188], but Fine & Gray model showed better calibration. CONCLUSION: It is feasible to develop a risk prediction model for new-onset CVD of breast cancer based on regional medical data in China. When not considering survival time, the XGBoost model and the Logistic regression model both showed better performance; Fine & Gray model showed better performance in consideration of survival time.

[Retrospective study on clinical manifestation, thigh MRI and electrophysiology characteristics of immune-mediated necrotizing myopathy].

Objective: To summarize the clinical, thigh magnetic resonance (tMRI) and electromyographic (EMG) characteristics in patients with immune-mediated necrotizing myopathy (IMNM). Methods: A total of 32 IMNM patients who were admitted to the Department of Neurology from April 2019 to April 2021 were enrolled at the First Medical Centre of Chinese PLA General Hospital. According to the type of antibody, the patients were divided into anti-SRP antibody positive (SRP+) group, anti-HMGCR antibody positive (HMGCR+) group and seronegative (SN) group. The gender, age, course of disease, myositis antibodies, extramuscular manifestations, EMG were collected and analyzed among three groups. The characteristics of skeletal muscle were assessed by tMRI inflammatory edema and fat infiltration scores. Analysis of variance, Kruskal-Wallis test and Chi-square test were used to compare the differences in different clinical characteristics and tMRI scores among the three groups. When there was a statistical difference among the three groups, the comparison between the two groups was corrected by the Bonferroni method. Result: (1) Of the 32 patients, 20 were females (62.5%).The median age of onset was 47±14 years, 25 (78.1%) patients had an acute or subacute course.There were 17 (53.1%) with SRP+, 8 (25.0%) with HMGCR+, and 7 (21.9%) with MSAs (myositis specific antibodies) negative. Anti-Ro52 antibody was the most common combined antibody (12/32, 37.5%), among which 10 were in SRP+group.(2) The CK of all patients were elevated, median was 5 948 (4 229, 7 664) U/L. There was no statistical difference of MMT scores among three groups. The proximal limb score was lower than distal limb (P<0.01). The axial muscle score was lower than the distal limb score (P<0.05).(3) Extramuscular manifestations of HMGCR+ group were lower than those of the other two groups (12.5% vs. 71.4% and 76.5%, P<0.017). Rash (60.0% vs.14.3%, P<0.05) and interstitial pulmonary diseases (70.0% vs. 14.3%, P<0.05) were more common in patients with anti-SRP coexistence with anti-Ro52 than those with isolated anti-SRP. Connective tissue disease was more common in SN group (57.1% vs. 11.8% and 0, P<0.017).(4) tMRI showed fascial edema of SN group was more obvious than that of the other two groups (P<0.017). There was no statistical difference in the degree of fat infiltration and inflammatory edema among three groups, but SRP+ group had more cases of early fat infiltration.(5) Myotonic potentials (25.0% vs. 0 and 0, P<0.017) and compound repetitive discharges (CRDs) (50.0% vs. 5.9% and 0, P<0.017) were common in HMGCR+ group. Proteomic analysis found significantly different expressed proteins in skeletal muscle of patients with myotonic potentials or CRDs were associated with cytoskeleton, cell junction and extracellular matrix. Conclusion: IMNM with pure anti-SRP antibody positive and anti-HMGCR positive were mainly affected by skeletal muscles. Those who were co-positive for anti-SRP antibody and anti-Ro52 antibody had more extramuscular manifestations, which might be a special subtype of SRP+ group. This study proposed for the first time that myofascial inflammatory edema is an early sign of SN-IMNM injury. EMG of HMGCR+group were more prone to myotonia potential and CRDs.

[Analysis of the treatment effect of posterior scleral reinforcement on pathological myopia].

Pathological myopia, a blinding eye disease, is the most common cause of visual impairment in Asian countries. The most obvious features of pathological myopia are the elongation of the eye axis, the appearance of posterior scleral staphyloma, and even degenerative changes in the retina and choroid, resulting in corresponding complications and ultimately leading to marked visual impairment. Controlling the elongated eye axis is a key factor in preventing the complications of pathological myopia. Posterior scleral reinforcement is the main surgical method to delay the elongation of the eye axis and treat the posterior scleral staphyloma. Although most studies have confirmed that posterior scleral reinforcement is effective in delaying axial elongation and treating myopia, some scholars hold negative views on this surgery. This article summarizes the relevant research results of posterior scleral reinforcement surgery in the treatment of pathological myopia, concerning patients' vision, refractive power, eye axis, and corneal curvature, and discusses the effectiveness of the surgery. (Chin J Ophthalmol, 2021, 57: 952-957).

[Clinical approach and prognosis of continuous neurological care after intensive care for the patients with severe and refractory anti-N-methyl-D-aspartate receptor encephalitis].

Objective: To study the clinical features, continuous care and prognosis of the patients with severe and refractory anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis after intensive care unit (ICU). Methods: Clinical data of patients with severe and refractory anti-NMDAR encephalitis, who were transferred from ICU to general ward of neurology between December 2015 and October 2019, were retrospectively reviewed and analyzed in the study. Results: Twenty patients (11 females and 9 males) were enrolled in the study. The median course of disease when patients were transferred to general ward was 4.4 (2.0, 6.0) months. Six cases were alert, 6 cases were in a coma, 5 were in the early recovery phase and 3 were in the late recovery phase. Severe malnutrition, pneumonia, urinary tract infections, bedsores and leukocytopenia were common complications. Seven out of 18 patients were tested positive for cerebrospinal fluid anti-NMDAR antibodies with high titers (≥1∶100). During this continuous therapy stage,10 patients were treated with intravenous immunoglobulin (IVIg), 1 with methylprednisolone, 2 with rituximab, 1 with intrathecal methotrexate and 1 received intravenous cyclophosphamide. All Patients were prescribed a long-term immunotherapy (mycophenolate mofetil 1.5-3.0 g/d). Sixteen patients (80%) had good prognosis (modified Rankin Scale (mRS)≤2), and the mortality was 10%, with follow-up time of 17.0 (8.0, 27.0) months. Conclusions: Patients with anti-NMDAR encephalitis, who are transferred from ICU, have severely impaired neurologic function. These patients need long-term individualized immunotherapy and continuous neurological care. Good outcomes can be achieved in most patients.

[Retinal image quality in northern rural Chinese adult population].

Objective: To assess the retinal image quality of the normal northern rural Chinese adult population. Methods: A normal population-based, cross-sectional study. From Oct, 2012 to Jan 2013, a clustered, random sampling procedure was used to select normal population who visual acuity≤ 0(LogMAR) and 30-69 years old from 2 villages. All eligible subjects were invited to undergo a comprehensive eye examination, and the retinal image quality related index were examined with pupil 4 mm using objective optical quality analysis systemⅡ(OQAS Ⅱ, Visiometrics, Spain), including MTFcutoff, VA20, VA9, PSF50, PSF10, OSI, SR. And describe the retinal image quality of different age group, including 30-39y, 40-49y, 50-59y, 60-69y. Results: Among 1 108 participants (61.9%) that completed examinations in our center, 681 participants (1 362 eyes) were recruited. There were 146, 586, 440 and 190 eyes in each group. The spherical equivalent refraction of each group was (-0.35±0.84), (-0.19±0.50), (-0.03±0.54) and (0.20±0.71) D. The best corrected vision acuity of each group was -0.02±0.04, -0.01±0.03, -0.01±0.02 and -0.00±0.01. The MTFcutoff of each group was (37.06±9.31), (36.69±8.93), (36.52±9.05) and (32.61±10.08) c/deg. Retinal imaging parameters were significantly different(MTFcutoff: MD=4.45, SR:MD=0.03, PSF50: MD=-0.45, PSF10: MD=-2.87, VA20:MD=0.13, A9:MD=0.09, OSI:MD=-0.41, P<0.001)between aged 30-39 group and aged 60-69 group. Objective scattering index (OSI) were significantly different(MD=-0.13, P=0.004)between aged 30-39 group and aged 50-59 group. Retinal imaging parameters were significantly different(MTFcutoff:MD=4.45, SR:MD=0.03, PSF50:MD=-0.45, PSF10:MD=-2.87, VA20:MD=0.13, VA9: MD=0.09, OSI: MD=-0.41, P<0.001)between aged 40-49 group and aged 60-69 group. Retinal imageing parameters were significantly different(MTFcutoff: MD=4.45, SR: MD=0.03, PSF50: MD=-0.45, PSF10: MD=-2.87, VA20:MD=0.13, VA9:MD=0.09, OSI:MD=-0.41,P<0.001)between aged 50-59 group and aged 60-69 group. Conclusion: Retinal image quality was gradually worse over time in the northern rural Chinese adult population. (Chin J Ophthalmol, 2018, 54:593-598).

[A preliminary study on macular retinal and choroidal thickness and blood flow change after posterior scleral reinforcement by optical coherence tomography angiography].

Objective: To investigate macular retinal and choroidal thickness and blood flow change using optical coherence tomography angiography after posterior scleral reinforcement (PSR) surgery. Methods: Prospective study. Twenty eyes of 10 patients with high myopia were enrolled in this open-label, single-treatment group and prospective study. Radial lines and Angio retina (3 mm×3 mm) module were performed for 20 eyes using Angio-vue optical coherence tomography (Avanti, Optovue) without pupil dilation, and best corrected visual acuity, spherical equivalent and axial length were compared before and 60 days after surgery. Retinal and choroidal thickness was measured in the fovea, 1 mm superior, 1 mm inferior, 1 mm nasal and 1 mm temporal to the fovea. Flow area, flow density and flow index were recorded using self-provided software in the superficial retina layer, deep retina layer, outer retina layer and choroid capillary layer, respectively. Statistical analysis was performed using SPSS 16.0. Data that followed normal distribution were compared with paired two-sample t-test, while others were compared with Wilcoxon signed rank test. Results: Of the patients participating in this preliminary study, the mean age was (35.5±4.2) years, and 50% were female. No significant difference was found between before and 60 days after PSR surgery in best corrected visual acuity (t=0.99, P=0.33), spherical equivalent (t=-1.89, P=0.07) and axial length (t=0.2, P=0.08). The retinal thickness in the fovea was thinner (Z=-2.58, P=0.01), while there was no significant difference in the 1 mm superior (t=0.44, P=0.67) , 1 mm inferior (t=0.05, P=0.96) , 1 mm nasal (Z=0.87, P=0.64) and 1 mm temporal (Z=-0.78, P=0.99) to the fovea. No significant difference was found in choroidal thickness (t=-0.12, P=0.87; t=-0.25, P=0.81. t=0.53, P=0.61; t=-0.91, P=0.38. t=1.2, P=0.25) before and after surgery. The postoperative flow density in the superficial and deep retinal layers (48.18±4.56% and 31.47±5.11%) was significantly increased (t=2.66, P=0.02; t=3.16, P=0.01) compared with pre-operation (33.82±4.33% and 14.29±3.89%). The postoperative flow index in the superficial and deep retina layers (0.044±0.005 and 0.025±0.005) was significantly increased (t=2.59, P=0.02. t=2.95, P=0.01) compared with pre-operation (0.028±0.004 and 0.010±0.003). The other flow measurements showed no significant difference. Conclusion: Retinal thickness decreased, and flow density and index increased in the superficial and deep retinal layers after PSR surgery. This suggested blood flow improvement in the macular region after PSR surgery in high myopic eyes. (Chin J Ophthalmol, 2017, 53:39-45).

Safranal prevents rotenone-induced oxidative stress and apoptosis in an in vitro model of Parkinson's disease through regulating Keap1/Nrf2 signaling pathway.

Safranal, a major constituent of saffron, possesses antioxidant and anti-apoptotic properties showing considerable neuroprotective effects. However, whether safranal shows therapeutic effect on Parkinson's disease (PD) remains unknown. In this study, we aimed to investigate the potential effect of safranal on PD using an in vitro model of PD induced by rotenone. We found that safranal significantly inhibited rotenone-induced cell death in a dose-dependent manner. Moreover, safranal also markedly suppressed the reactive oxygen species (ROS) generation and cell apoptosis induced by rotenone. Further investigation showed that safranal inhibited the expression of kelch-like ECH-associated protein 1 (Keap1) and promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) in rotenone-induced dopaminergic neurons. Meanwhile, the downstream antioxidant enzyme genes of Nrf2 including glutathione S transferase (GST), glutamate-cysteine ligase catalytic subunit (GCLc), NADPH-quinone oxidoreductase 1 (NQO1) and heme oxygenase1 (HO-1) were also induced by safranal in rotenone-induced dopaminergic neurons. However, the knockdown of Nrf2 significantly abrogated the protective effect of safranal on rotenone-induced neurotoxicity. Taken together, our study suggests that safranal protects against rotenone-induced neurotoxicity associated with Nrf2 signaling pathway implying that safranal may serve as a potent and promising therapeutic drug for the treatment of PD.

[Screening for carriers of pathogenic genes for methylmalonic acidemia and Wilson's disease in neonates in Qingdao].

Objective: To investigate the carrier frequency of pathogenic genes for methylmalonic acidemia and Wilson's disease in neonates in Qingdao. Methods: In this cross-sectional study, using computer random sampling, 5 020 neonates from the neonatal screening center in Qingdao area from June 2016 to December 2018 were selected, and 5 012 of them were included in the carrier screening study.DNA was extracted from dried blood stain specimens used in the screening of newborns. Multiplex PCR combined with next generation sequencing were used for gene detection of MMACHC gene, MUT gene and ATP7B gene. The carrying rate of hotspots of each gene were calculated, and binomial distribution method was used to calculate 95% confidence interval of pathogenic gene carrying rate. Results: A total of 5 012 neonates completed the screening for carriers of disease-causing genes, of which 5 006 neonates completed the screening of two diseases and the remaining 6 neonates completed the screening of Wilson disease only.For ATP7B gene, the carrier frequency of the 12 hot spot mutations was 1.46% (73/5 012),and the 95% confidence interval was 1.16%-1.83%. For MMACHC gene and MUT gene, carrier frequency of 18 hot spot mutations was 2.50% (125/5 006) , and the 95% confidence interval was 2.10%-2.97%, among which cblC type accounted for 87.2% and the MUT pathogenic gene accounted for 12.8%. Conclusion: The carrier frequency of methylmalonic acidemia and Wilson's disease are both high in the neonatal population in Qingdao.

Effects of sevoflurane post-conditioning in cerebral ischemia-reperfusion injury via TLR4/NF-κB pathway in rats.

OBJECTIVE: The aim of the study was to investigate the anti-inflammatory effect of sevoflurane post-conditioning on cerebral ischemia-reperfusion injury in rats. MATERIALS AND METHODS: Thirty Sprague Dawley (SD) rats were randomly divided into 3 groups: sham operation group (Sham), ischemia/reperfusion injury (I/R) group and sevoflurane post-conditioning group (Se). Hematoxylin-eosin (HE) staining was used to observe the inflammatory response in the brain tissue. The levels of TNF-α, IL-1ß, IL-6 in serum were measured by ELISA. The mRNA and protein expression of TLR4 and NF-κB p65 were detected by RT-PCR and Western blot in the brain tissue. RESULTS: The post-conditioning of sevoflurane decreased the level of inflammatory reaction in ischemic-reperfusion rat cerebral infarction area and reduced the levels of pro-inflammatory cytokines such as TNF-α, IL-1ß, IL-6 in rats with ischemia-reperfusion injury. In addition, after treatment with sevoflurane, the mRNA and protein expression of TLR4 and NF-κBp65 in TLR4/NF-κB pathway was inhibited. CONCLUSIONS: Sevoflurane post-conditioning can decrease the inflammatory reaction in cerebral infarct area induced by cerebral ischemia-reperfusion injury in rats. The neuroprotective effect mechanism of sevoflurane may be related to TLR4/NF-κB signaling pathway.

Inflammation and activity augment brain-derived neurotrophic factor peripheral release.

Brain-derived neurotrophic factor (BDNF) release to nerve terminals in the central nervous system is crucial in synaptic transmission and neuronal plasticity. However, BDNF release peripherally from primary afferent neurons has not been investigated. In the present study, we show that BDNF is synthesized by primary afferent neurons located in the dorsal root ganglia (DRG) in rat, and releases to spinal nerve terminals in response to depolarization or visceral inflammation. In two-compartmented culture that separates DRG neuronal cell bodies and spinal nerve terminals, application of 50mM K(+) to either the nerve terminal or the cell body evokes BDNF release to the terminal compartment. Inflammatory stimulation of the visceral organ (e.g. the urinary bladder) also facilitates an increase in spontaneous BDNF release from the primary afferent neurons to the axonal terminals. In the inflamed viscera, we show that BDNF immunoreactivity is increased in nerve fibers that are immuno-positive to the neuronal marker PGP9.5. Both BDNF and pro-BDNF levels are increased, however, pro-BDNF immunoreactivity is not expressed in PGP9.5-positive nerve-fiber-like structures. Determination of receptor profiles in the inflamed bladder demonstrates that BDNF high affinity receptor TrkB and general receptor p75 expression levels are elevated, with an increased level of TrkB tyrosine phosphorylation/activity. These results suggest a possibility of pro-proliferative effect in the inflamed bladder. Consistently we show that the proliferation marker Ki67 expression levels are enhanced in the inflamed organ. Our results imply that in vivo BDNF release to the peripheral organ is an important event in neurogenic inflammatory state.

Insulin-induced insulin receptor substrate-1 degradation is mediated by the proteasome degradation pathway.

Insulin receptor substrate (IRS) proteins are important intracellular molecules that mediate insulin receptor tyrosine kinase signaling. A decreased content of IRS proteins has been found in insulin-resistant states in animals, humans, and cultured cells under various conditions. However, the molecular mechanism that controls cellular levels of IRS proteins is unknown. We report that chronic insulin treatment induces the degradation of IRS-1, but not IRS-2, protein in cultured cells. The insulin-induced degradation of IRS-1 can be prevented by pretreatment with lactacystin, a specific inhibitor for proteasome degradation. These data demonstrate, for the first time, that insulin-induced degradation of IRS-1 is mediated by the proteasome degradation pathway. IRS-2 can escape from the insulin-induced proteasome degradation, suggesting the existence of specific structural requirements for this degradation process.

Function and molecular basis of action of vasopressin 4-8 and its analogues in rat brain.

VP 4-8 as a highly potent behavioral-active metabolite of arginine-vasopressin (VP) has been studied in detail at four levels, i.e. ligand level, membrane binding level, intracellular level and nuclear level. The purpose of this chapter is to review and discuss the main results obtained from our recent pharmacological and biochemical investigations which are described as follows: 1, structure-function relationship of VP 4-8 and its analogs; 2, some characters of VP 4-8-specific binding, the distribution of the binding sites in the rat brain and the consequent effect on long-term potentiation of synaptic transmission; 3, a putative receptor-mediated signaling pathway involving second messenger IP3, immediately-early gene c-fos transcription and protein kinase PKC, CaMKII and MAPK; 4, peptide-induced enhancement of some crucial functional proteins such as calmodulin, nerve growth factor (NGF) and brain-derived nerve growth factor (BDNF). The physiological significance of the events following VP 4-8 administration and particularly, its possible role in learning and memory processes are discussed.

[Effect of AVP(4-8) administration on Ca2+/CaM-dependent protein kinase II autophosphorylation in rat brain].

The extent increase of Ca2+/CaM-dependent protein kinase II (CaMK II) autophosphorylation in various brain regions of rat reached a maximum value, one hour after s.c. administration of AVP(4-8). The increase in the cortex amounted to 192% of the control (P < 0.001), while in the hippocampus only 40% (P < 0.05). The autophosphorylation of CaMK II was dependent on both Ca2+ and CaM. Western blotting with anti-CaMK II alpha monoclonal antibody showed that the content of CaMK II alpha in cortex did not show detectable change in 1 h as compared to the control group. ZDC(C)PR, an antagonist of AVP(4-8), markedly blocked the effect of AVP(4-8), suggesting that AVP (4-8) stimulated CaMK II autophosphorylation is mediated through its receptor.

Prolonged sympathetic innervation of sensory neurons in rat thoracolumbar dorsal root ganglia during chronic colitis.

BACKGROUND: Peripheral irritation-induced sensory plasticity may involve catecholaminergic innervation of sensory neurons in the dorsal root ganglia (DRG). METHODS: Catecholaminergic fiber outgrowth in the thoracolumbar DRG (T13-L2) was examined by tyrosine hydroxylase (TH) immunostaining, or by sucrose-potassium phosphate-glyoxylic acid histofluorescence method. TH level was examined by Western blot. Colonic afferent neurons were labeled by retrograde neuronal tracing. Colitis was induced by intracolonic instillation of tri-nitrobenzene sulfonic acid (TNBS). KEY RESULTS: The catecholaminergic fibers formed 'basket-like' structures around the DRG cells. At 7 days following TNBS treatment, the number of DRG neurons surrounded by TH-immunoreactive fibers and the protein levels of TH were significantly increased in T13, L1, and L2 DRGs (two- to threefold, P < 0.05). The DRG neurons that were surrounded by TH immunoreactivity were 200 kDa neurofilament-positive, but not isolectin IB4-positive or calcitonin gene-related peptide-positive. The TH-immunoreactive fibers did not surround but adjoin the specifically labeled colonic afferent neurons, and was co-localized with glial marker S-100. Comparison of the level of TH and the severity of colonic inflammation showed that following TNBS treatment, the degree of colonic inflammation was most severe at day 3, subsided at day 7, and significantly recovered by day 21. However, the levels of TH in T13-L2 DRGs were increased at both 3 days and 7 days post TNBS treatment and persisted up to 21 days (two- to fivefold increase, P < 0.05) as examined. CONCLUSIONS & INFERENCES: Colonic inflammation induced prolonged catecholaminergic innervation of sensory neurons, which may have relevance to colitis-induced chronic visceral hypersensitivity and/or referred pain.

Distribution and quantification of ß-3 adrenergic receptor in tissues of sheep.

The ß-3 adrenergic receptor (ADRB3) is a G-protein coupled receptor involved in regulating lipolysis, as part of homeostatic regulation. In this study, South African Mutton Merino and Shanxi Dam Line were used to study the distribution and quantification of ADRB3 in adipose (subcutaneous, omental, retroperitoneal, mesenteric and perirenal fat) and non-adipose (heart, liver, spleen, lung and kidney) tissues of sheep. The protein was determined by immunohistochemical technique and by mRNA abundance via real-time polymerase chain reaction. ADRB3 was detected in all studied tissues with abundance in adipose tissues higher than in non-adipose tissues (P < 0.001). For adipose tissues, greater expression was found in deep deposits such as great omental and retroperitoneal fat than in subcutaneous fat (P < 0.05). Significant differences (P < 0.05) both for mRNA and for protein expression also existed between the two sheep flocks. These findings are consistent with the known function of ADRB3 in mediating lipolysis and homeostasis in adipose tissues.

Differential changes in brain-derived neurotrophic factor and extracellular signal-regulated kinase in rat primary afferent pathways with colitis.

Brain-derived neurotrophic factor (BDNF) has been postulated to participate in inflammation-induced visceral hypersensitivity by modulating the sensitivity of visceral afferents through the activation of intracellular signalling pathways such as the extracellular signal-regulated kinase (ERK) pathway. In the current study, we assessed the expression levels of BDNF and phospho-ERK in lumbosacral dorsal root ganglia (DRG) and spinal cord before and during tri-nitrobenzene sulfonic acid (TNBS)-induced colitis in rats with real-time PCR, ELISA, western blot and immunohistochemical techniques. BDNF mRNA and protein levels were increased in L1 and S1 but not L6 DRG when compared with control (L1: two- to five-fold increases, P < 0.05; S1: two- to three-fold increases, P < 0.05); however, BDNF protein but not mRNA level was increased in L1 and S1 spinal cord when compared with control. In parallel, TNBS colitis significantly induced phospho-ERK1/2 expression in L1 (four- to five-fold, P < 0.05) and S1 (two- to three-fold, P < 0.05) but not in L6 spinal cord levels. Immunohistochemistry results showed that the increase in phospho-ERK1/2 expression occurred at the region of the superficial dorsal horn and grey commisure of the spinal cord. In contrast, there was no change in phospho-ERK5 in any level of the spinal cord examined during colitis. The regional and time-specific changes in the levels of BDNF mRNA, protein and phospho-ERK with colitis may be a result of increased transcription of BDNF in DRG and anterograde transport of BDNF from DRG to spinal cord where it activates intracellular signalling molecules such as ERK1/2.

Penetration of topically applied levofloxacin into eyes with thin-wall filtering bleb after trabeculectomy.

PURPOSE: To investigate the comparative penetration of 0.3% levofloxacin eye drops into the aqueous humour between cataract patients with or without (control) thin-wall filtering blebs. METHODS: One drop of 0.3% levofloxacin was administered to the eyes at 30-min intervals for 3.5 h before phacoemulcification for both groups. Aqueous humour samples (0.1-0.2 ml) were aspirated during surgery. The concentration of levofloxacin in the aqueous humour was determined by high-performance liquid chromatography. The Student's t-test, Pearson correlation, and chi(2) test were used to compare the data of the two groups. A P<0.05 was required for results to be considered statistically significant. RESULTS: The levofloxacin concentration in the aqueous humour was significantly increased (P<0.0001) in the bleb (mean+SD: 3.7+/-2.3 microg/ml) vscontrol group (0.4+/-0.2 microg/ml). Intraocular pressure and the bleb area were not correlated with levofloxacin concentration. CONCLUSION: The presence of thin-wall filtering blebs increases intraocular penetration of topically administered levofloxacin.

[Increase of mitogen-activated protein kinase activity in rat brain after injection of argipressin (4-8)].

AIM: To study the changes of mitogen-activated protein kinase (MAPK) activity in rat brain stimulated by argipressin (4-8) (AVP (4-8)) (s.c.). METHODS: Wistar rat was treated with AVP (4-8). MAPK activity in rat brain was assayed by phosphorylation of its specific substrate myelin basic protein (MBP) after the cytosolic extracts fractionated by MONO-Q anion-exchange chromatography. RESULTS: The activity of 44 kDa MAPK in rat brain was significantly enhanced by AVP (4-8). The enhancement of MAPK activity in hippocampus was suppressed 80% by ZDC(C)CPR, an antagonist of AVP(4-8). The level of 44 kDa MAPK protein had no detectable differences between the administration groups and control. In rat hippocampal slices, similar results were obtained. CONCLUSION: The increasement of 44 kDa MAPK activity stimulated by AVP(4-8) was mediated by its specific receptor, and was a short-period process activated by protein phosphorylation, but not by protein expression. MAPK was involved in the signal transduction pathway induced by AVP(4-8).

Involvement of a putative G-protein-coupled receptor and a branching pathway in argipressin (4-8) signal transduction in rat hippocampus.

AIM: To study the signal transduction pathway induced by argipressin (4-8) (AVP4-8) in rat hippocampus. METHODS: Rat hippocampi were sectioned transversely at 300 microns with a tissue chopper and transferred to fresh incubation solution circulated with a humidified gas mixture of 95% O2 + 5% CO2 at 36 +/- 0.5 degrees C. After incubation with various drugs, MAP kinase (MAPK) activity and Ca2+/calmodulin-dependent protein kinase II (CaMKII) autophosphorylation were measured. RESULTS: The main findings are: (1) The AVP4-8-stimulated MAPK activity and the CaMKII autophosphorylation were blocked by ZDC(C)PR, an antagonist of AVP4-8, and also completely inhibited by pertussis toxin, a selective inhibitor of the G-protein-coupled receptor (GPCR). But, AVP-induced MAPK activation was not sensitive to ZDC(C)PR or PTX. (2) Polymyxin B (PMB), an inhibitor of protein kinase C (PKC), markedly suppressed the peptide-activation of MAPK, but did not affect CaMKII autophosphorylation. Phorbol myristate acetate (TPA), an activator of PKC, elicited an increase of MAPK activity, but did not further influence the level of AVP4-8-enhanced MAPK activity; Nevertheless, the extent of CaMKII activation was attenuated by TPA. (3) The enhancement of MAPK activity was not reduced by KN-62, a specific inhibitor of CaMKII. (4) AVP4-8 did not show any influence on cAMP production. CONCLUSION: AVP4-8 stimulated signal transduction via a GPCR and a branching pathway in rat hippocampus.

The production and assessment of a plastic rod for the Chinese Reference Preparation for Opacity.

A reference preparation for opacity consisting of a plastic rod was introduced by Perkins et al. in 1973. It was adopted as the International Reference Preparation for Opacity in 1975. This plastic rod opacity reference preparation has been used to standardize the Chinese National Bacterial Opacity Standard. The material was prepared from plastic sheet by a water-bath method and by a dry-heat method; the sheet was then machined into the plastic rods. We have studied the technical processes and set up methods for the examination of the sheets and rods. The water-bath method was found to be better than the dry-heat method in our tests. Collaborative assays in research institutes of biological products have shown that the plastic rod can replace the glass-powder suspension. The duration of validity of the plastic rod opacity reference preparation and that of the glass-powder suspension used for the Chinese National Bacterial Opacity Standard were studied and found to be similar. For this reason the plastic rod opacity reference preparation has not been widely used in China.