D-4F Induces Heme Oxygenase-1 and Extracellular Superoxide Dismutase, Decreases Endothelial Cell Sloughing, and Improves Vascular Reactivity in Rat Model of Diabetes

Background— Apolipoprotein A1 mimetic peptide, synthesized from D-amino acid (D-4F), enhances the ability of HDL to protect LDL against oxidation in atherosclerotic animals.

Methods and Results— We investigated the mechanisms by which D-4F provides antioxidant effects in a diabetic model. Sprague-Dawley rats developed diabetes with administration of streptozotocin (STZ). We examined the effects of daily D-4F (100 μg/100 g of body weight, intraperitoneal injection) on superoxide (O 2 − ), extracellular superoxide dismutase (EC-SOD), vascular heme oxygenase (HO-1 and HO-2) levels, and circulating endothelial cells in diabetic rats. In response to D-4F, both the quantity and activity of HO-1 were increased. O 2 − levels were elevated in diabetic rats (74.8±8×10 3 cpm/10 mg protein) compared with controls (38.1±8×10 3 cpm/10 mg protein; P <0.01). D-4F decreased O 2 − levels to 13.23±1×10 3 ( P <0.05 compared with untreated diabetics). The average number of circulating endothelial cells was higher in diabetics (50±6 cells/mL) than in controls (5±1 cells/mL) and was significantly decreased in diabetics treated with D-4F (20±3 cells/mL; P <0.005). D-4F also decreased endothelial cell fragmentation in diabetic rats. The impaired relaxation typical of blood vessels in diabetic rats was prevented by administration of D-4F (85.0±2.0% relaxation). Western blot analysis showed decreased EC-SOD in the diabetic rats, whereas D-4F restored the EC-SOD level.

Conclusions— We conclude that an increase in circulating endothelial cell sloughing, superoxide anion, and vasoconstriction in diabetic rats can be prevented by administration of D-4F, which is associated with an increase in 2 antioxidant proteins, HO-1 and EC-SOD.

20-HETE Signals Through G-Protein-Coupled Receptor GPR75 (Gq) to Affect Vascular Function and Trigger Hypertension

RATIONALE

20-Hydroxyeicosatetraenoic acid (20-HETE), one of the principle cytochrome P450 eicosanoids, is a potent vasoactive lipid whose vascular effects include stimulation of smooth muscle contractility, migration, and proliferation, as well as endothelial cell dysfunction and inflammation. Increased levels of 20-HETE in experimental animals and in humans are associated with hypertension, stroke, myocardial infarction, and vascular diseases.

OBJECTIVE

To date, a receptor/binding site for 20-HETE has been implicated based on the use of specific agonists and antagonists. The present study was undertaken to identify a receptor to which 20-HETE binds and through which it activates a signaling cascade that culminates in many of the functional outcomes attributed to 20-HETE in vitro and in vivo.

METHODS AND RESULTS

Using crosslinking analogs, click chemistry, binding assays, and functional assays, we identified G-protein receptor 75 (GPR75), currently an orphan G-protein-coupled receptor (GPCR), as a specific target of 20-HETE. In cultured human endothelial cells, 20-HETE binding to GPR75 stimulated Gα_q/11 protein dissociation and increased inositol phosphate accumulation and GPCR-kinase interacting protein-1-GPR75 binding, which further facilitated the c-Src-mediated transactivation of epidermal growth factor receptor. This results in downstream signaling pathways that induce angiotensin-converting enzyme expression and endothelial dysfunction. Knockdown of GPR75 or GPCR-kinase interacting protein-1 prevented 20-HETE-mediated endothelial growth factor receptor phosphorylation and angiotensin-converting enzyme induction. In vascular smooth muscle cells, GPR75-20-HETE pairing is associated with Gα_q/11- and GPCR-kinase interacting protein-1-mediated protein kinase C-stimulated phosphorylation of MaxiKβ, linking GPR75 activation to 20-HETE-mediated vasoconstriction. GPR75 knockdown in a mouse model of 20-HETE-dependent hypertension prevented blood pressure elevation and 20-HETE-mediated increases in angiotensin-converting enzyme expression, endothelial dysfunction, smooth muscle contractility, and vascular remodeling.

CONCLUSIONS

This is the first report to identify a GPCR target for an eicosanoid of this class. The discovery of 20-HETE-GPR75 pairing presented here provides the molecular basis for the signaling and pathophysiological functions mediated by 20-HETE in hypertension and cardiovascular diseases.

Amitriptyline up-regulates connexin43-gap junction in rat cultured cortical astrocytes via activation of the p38 and c-Fos/AP-1 signalling pathway

BACKGROUND AND PURPOSE

Intercellular communication via gap junctions, comprised of connexin (Cx) proteins, allow for communication between astrocytes, which in turn is crucial for maintaining CNS homeostasis. The expression of Cx43 is decreased in post-mortem brains from patients with major depression. A potentially novel mechanism of tricyclic antidepressants is to increase the expression and functioning of gap junctions in astrocytes.

EXPERIMENTAL APPROACH

The effect of amitriptyline on the expression of Cx43 and gap junction intercellular communication (GJIC) in rat primary cultured cortical astrocytes was investigated. We also investigated the role of p38 MAPK intracellular signalling pathway in the amitriptyline-induced expression of Cx43 and GJIC.

KEY RESULTS

Treatment with amitriptyline for 48 h significantly up-regulated Cx43 mRNA, protein and GJIC. The up-regulation of Cx43 was not monoamine-related since noradrenaline, 5-HT and dopamine did not induce Cx43 expression and pretreatment with α- and β-adrenoceptor antagonists had no effect. Intracellular signalling involved p38 MAPK, as amitriptyline significantly increased p38 MAPK phosphorylation and Cx43 expression and GJIC were significantly blocked by the p38 inhibitor SB 202190. Furthermore, amitriptyline-induced Cx43 expression and GJIC were markedly reduced by transcription factor AP-1 inhibitors (curcumin and tanshinone IIA). The translocation of c-Fos from the cytosol and the nucleus of cortical astrocytes was increased by amitriptyline, and this response was dependent on p38 activity.

CONCLUSION AND IMPLICATION

These findings indicate a novel mechanism of action of amitriptyline through cortical astrocytes, and further suggest that targeting this mechanism could lead to the development of a new class of antidepressants.

Androgen-dependent hypertension is mediated by 20-hydroxy-5,8,11,14-eicosatetraenoic acid-induced vascular dysfunction: role of inhibitor of kappaB Kinase

Increased vascular synthesis of 20-hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE) is associated with increased vascular contraction, endothelial dysfunction, and endothelial activation; all are believed to account for 20-HETE prohypertensive properties. We demonstrated previously that the 20-HETE-dependent inhibition of NO production is mediated through inhibitor of κB kinase (IKK), suggesting a cross-talk between 20-HETE-mediated endothelial dysfunction and activation. In this study, we examined the temporal relationship among blood pressure, endothelial dysfunction, and endothelial activation and the role of IKK in the rat model of androgen-driven 20-HETE-mediated hypertension. In Sprague-Dawley rats treated with 5α-dihydrotestosterone, renal vascular 20-HETE levels increased by day 2 of treatment from 17.7±2.4 to 57.7±9.7 ng/mg, whereas blood pressure elevation reached significance by day 3 (132.7±1.7 versus 117.2±0.8 mm Hg). In renal interlobar arteries, when compared with vehicle, 5α-dihydrotestosterone treatment increased the sensitivity to phenylephrine-induced vasoconstriction by 3.5-fold, decreased acetylcholine-induced vasorelaxation, and increased nuclear factor κB activity, all of which were attenuated by treatment with the 20-HETE antagonist, 20 hydroxyeicosa-6(Z),15(Z)-dienoic acid, (20-6,15-HEDE). Cotreatment with parthenolide, an IKK inhibitor, attenuated the androgen-dependent 20-HETE-mediated elevation in blood pressure (from 133.7±3.1 to 109.8±3.0 mm Hg). In addition, parthenolide treatment negated 20-HETE-mediated inhibition of the relaxing response to acetylcholine and 20-HETE-mediated increase in vascular nuclear factor κB activity. These findings suggest that inhibition of IKK attenuates the androgen-dependent 20-HETE-mediated increase in blood pressure by inhibiting both 20-HETE-dependent endothelial activation and dysfunction.

Twenty-four-color spectral karyotyping reveals chromosome aberrations in cytogenetically normal acute myeloid leukemia

Multicolor spectral karyotyping allows simultaneous visualization of all human chromosomes and screening for chromosomal rearrangements without a priori knowledge of any abnormalities involved. Based on this potentially increased sensitivity, we investigated, in a preliminary manner, whether spectral karyotyping could detect cytogenetic aberrations in karyotypically normal leukemia. The test population was comprised of 28 cryopreserved, cytogenetically normal acute myeloid leukemia (AML) samples from patients registered to a randomized trial for previously untreated AML (SWOG 9031). Two normal and 12 samples with known cytogenetic aberrations were used to validate and establish the diagnostic accuracy of the spectral karyotyping assay and instrumentation in a clinical setting. Enumeration and region-specific DNA fluorescence in situ hybridization (FISH) probes verified discrepant results. In the validation data set, spectral karyotyping refined complex karyotypic rearrangements in six cases and defined the chromosomal origin of a "jumping" homogeneously staining region; however, the technology was less sensitive in the detection of subtelomeric rearrangements and double minute chromosomes. In the test population, spectral karyotyping identified previously undetected cytogenetic aberrations in two cases (7%) of karyotypically normal AML: a cryptic 11q23 translocation in 20/20 cells and a minor monosomy 7 clone in 3/21 cells (FISH, 10.5%). Both of these abnormalities are considered to confer a poor prognosis when based on classical cytogenetic prognostic criteria. As an adjunct to classical cytogenetics and standard FISH analyses, the additive resolution of spectral karyotyping, in particular, with chromosome paints spiked with subtelomeric and/or locus-specific probes, may allow significant gains to be made in diagnostic accuracy and recognition of genotype/phenotype prognostic relationships, and in defining underlying biologic mechanisms in cancer. Genes Chromosomes Cancer 28:318-328, 2000.

History of medical screening: from concepts to action

The objective of medical screening is to identify disease in its preclinical, and therefore hopefully still curable, phase. This may have been an old quest in medicine but it became historically possible when at least four conditions were met: the availability of simple, valid and acceptable forms of tests, the discovery of effective treatments, the establishment of a theory of screening, and the wide access to health care. Five selected examples that illustrate the history of medical screening are reviewed: screening for psychiatric disorders in the United States army as it is one of the oldest screening programmes; screening for syphilis as it used one of the earliest screening tests; screening for diabetes as one of the first modern forms of mass screening; screening for cervical cancer using the Pap test as one of the greatest successes of screening; and screening for breast cancer by mammography as this offers a good opportunity to discuss the development of modern evaluation of screening programmes. The evaluation of the impact of screening on human health slowly progressed, from obvious changes in the vital statistics such as the decline in incidence of syphilis, to less obvious changes such as the decline in mortality of cancer of the uterus, to finally more subtle changes, such as the impact of mammographic screening on breast cancer mortality. Methods of evaluation had therefore to adapt, evolving from simple surveys to case-control studies and randomised trials. The history of screening is short, but very rich and mostly still to be written.

Primary cultures of rat cortical microglia treated with nicotine increases in the expression of excitatory amino acid transporter 1 (GLAST) via the activation of the α7 nicotinic acetylcholine receptor

Although the clearance of glutamate from the synapse under physiological conditions is performed by astrocytic glutamate transporters, their expression might be diminished under pathological conditions. Microglia glutamate transporters, however, might serve as a back-up system when astrocytic glutamate uptake is impaired, and could have a prominent neuroprotective function under pathological conditions. In the current study, the effect of nicotine, well known as a neuroprotective molecule, on the function of glutamate transporters in cultured rat cortical microglia was examined. Reverse transcription polymerase chain reaction and pharmacological approaches demonstrated that, glutamate/aspartate transporter (GLAST), not glutamate transporter 1 (GLT-1), is the major functional glutamate transporter in cultured cortical microglia. Furthermore, the α7 subunit was demonstrated to be the key subunit comprising nicotinic acetylcholine (nACh) receptors in these cells. Treatment of cortical microglia with nicotine led to a significant increase of GLAST mRNA expression and (14)C-glutamate uptake in a concentration- and time-dependent manner, which were markedly inhibited by pretreatment with methyllycaconitine, a selective α7 nACh receptor antagonist. The nicotine-induced expression of GLAST mRNA and protein is mediated through an inositol trisphosphate (IP3) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) depend intracellular pathway, since pretreatment with either xestospongin C, an IP3 receptor antagonist, or KN-93, a CaMKII inhibitor, blocked GLAST expression. Together, these findings indicate that activation of nACh receptors, specifically those expressing the α7 subunit, on cortical microglia could be a key mechanism of the neuroprotective effect of nACh receptor ligands such as nicotine.

Angiotensin II receptor blockade or deletion of vascular endothelial ACE does not prevent vascular dysfunction and remodeling in 20-HETE-dependent hypertension

Increased vascular 20-HETE is associated with hypertension and activation of the renin-angiotensin system (RAS) through induction of vascular angiotensin-converting enzyme (ACE) expression. Cyp4a12tg mice, whose Cyp4a12-20-HETE synthase expression is under the control of a tetracycline (doxycycline, DOX) promoter, were used to assess the contribution of ACE/RAS to microvascular remodeling in 20-HETE-dependent hypertension. Treatment of Cyp4a12tg mice with DOX increased systolic blood pressure (SBP; 136 ± 2 vs. 102 ± 1 mmHg; P < 0.05), and this increase was prevented by administration of 20-HEDGE, lisinopril, or losartan. DOX-induced hypertension was associated with microvascular dysfunction and remodeling of preglomerular microvessels, which was prevented by 20-HEDGE, a 20-HETE antagonist, yet only lessened, but not prevented, by lisinopril or losartan. In ACE 3/3 mice, which lack vascular endothelial ACE, administration of 5α-dihydrotestosterone (DHT), a known inducer of 20-HETE production, increased SBP; however, the increase was about 50% of that in wild-type (WT) mice (151 ± 1 vs. 126 ± 1 mmHg). Losartan and 20-HEDGE prevented the DHT-induced increase in SBP in WT and ACE 3/3 mice. DHT treatment increased 20-HETE production and microvascular remodeling in WT and ACE 3/3 mice; however, remodeling was attenuated in the ACE 3/3 mice as opposed to WT mice (15.83 ± 1.11 vs. 22.17 ± 0.92 μm; P < 0.05). 20-HEDGE prevented microvascular remodeling in WT and ACE 3/3 mice, while losartan had no effect on microvascular remodeling in ACE 3/3. Taken together, these results suggest that RAS contributes to 20-HETE-mediated microvascular remodeling in hypertension and that 20-HETE-driven microvascular remodeling independent of blood pressure elevation does not fully rely on ACE activity in the vascular endothelium.

Topology of the Na(+)/dicarboxylate cotransporter: the N-terminus and hydrophilic loop 4 are located intracellularly

The current secondary structure model of the Na(+)/dicarboxylate cotransporter, NaDC-1, contains 11 transmembrane domains. The model is based on hydropathy analysis and the extracellular location of the carboxy terminus, which contains an N-glycosylation site. In this study, the model was further tested using indirect immunofluorescence of COS-7 cells. The Flag epitope tag (DYKDDDDK) was fused to the amino terminus of NaDC-1 (Flag-NaDC-1), and a monoclonal antibody against the Flag epitope was used to determine the location of the N-terminus. Hydrophilic loop 4 of NaDC-1 was identified using polyclonal antibodies raised against a fusion protein containing amino acids 164--233 of NaDC-1. The expression of NaDC-1 and Flag-NaDC-1 in COS-7 cells was confirmed by functional assays of succinate transport and by Western blots of cell surface biotinylated proteins. Immunofluorescent labeling of cells expressing both NaDC-1 and Flag-NaDC-1 required permeabilization of the plasma membranes with digitonin whereas no immunofluorescence was visible in intact cells. The results of this study show that both the N-terminus and hydrophilic loop 4 of NaDC-1 are located intracellularly, which supports the current model of NaDC-1 structure.

Cardiovascular function in male and female JCR:LA-cp rats: effect of high-fat/high-sucrose diet

Thirty percent of the world population is diagnosed with metabolic syndrome. High-fat/high-sucrose (HF/HS) diet (Western diet) correlates with metabolic syndrome prevalence. We characterized effects of the HF/HS diet on vascular (arterial stiffness, vasoreactivity, and coronary collateral development) and cardiac (echocardiography) function, oxidative stress, and inflammation in a rat model of metabolic syndrome (JCR rats). Furthermore, we determined whether male versus female animals were affected differentially by the Western diet. Cardiovascular function in JCR male rats was impaired versus normal Sprague-Dawley (SD) rats. HF/HS diet compromised cardiovascular (dys)function in JCR but not SD male rats. In contrast, cardiovascular function was minimally impaired in JCR female rats on normal chow. However, cardiovascular function in JCR female rats on the HF/HS diet deteriorated to levels comparable to JCR male rats on the HF/HS diet. Similarly, oxidative stress was markedly increased in male but not female JCR rats on normal chow but was equally exacerbated by the HF/HS diet in male and female JCR rats. These results indicate that the Western diet enhances oxidative stress and cardiovascular dysfunction in metabolic syndrome and eliminates the protective effect of female sex on cardiovascular function, implying that both males and females with metabolic syndrome are at equal risk for cardiovascular disease.NEW & NOTEWORTHY Western diet abolished protective effect of sex against cardiovascular disease (CVD) development in premenopausal animals with metabolic syndrome. Western diet accelerates progression of CVD in male and female animals with preexisting metabolic syndrome but not normal animals. Exacerbation of baseline oxidative stress correlates with accelerated progression of CVD in metabolic syndrome animals on Western diet.

Elevated 20-HETE in metabolic syndrome regulates arterial stiffness and systolic hypertension via MMP12 activation

Arterial stiffness plays a causal role in development of systolic hypertension. 20-hydroxyeicosatetraeonic acid (20-HETE), a cytochrome P450 (CYP450)-derived arachidonic acid metabolite, is known to be elevated in resistance arteries in hypertensive animal models and loosely associated with obesity in humans. However, the role of 20-HETE in the regulation of large artery remodeling in metabolic syndrome has not been investigated. We hypothesized that elevated 20-HETE in metabolic syndrome increases matrix metalloproteinase 12 (MMP12) activation leading to increased degradation of elastin, increased large artery stiffness and increased systolic blood pressure. 20-HETE production was increased ~7 fold in large, conduit arteries of metabolic syndrome (JCR:LA-cp, JCR) vs. normal Sprague-Dawley (SD) rats. This correlated with increased elastin degradation (~7 fold) and decreased arterial compliance (~75% JCR vs. SD). 20-HETE antagonists blocked elastin degradation in JCR rats concomitant with blocking MMP12 activation. 20-HETE antagonists normalized, and MMP12 inhibition (pharmacological and MMP12-shRNA-Lnv) significantly improved (~50% vs. untreated JCR) large artery compliance in JCR rats. 20-HETE antagonists also decreased systolic (182 ± 3 mmHg JCR, 145 ± 3 mmHg JCR + 20-HETE antagonists) but not diastolic blood pressure in JCR rats. Whereas diastolic pressure was fully angiotensin II (Ang II)-dependent, systolic pressure was only partially Ang II-dependent, and large artery stiffness was Ang II-independent. Thus, 20-HETE-dependent regulation of systolic blood pressure may be a unique feature of metabolic syndrome related to high 20-HETE production in large, conduit arteries, which results in increased large artery stiffness and systolic blood pressure. These findings may have implications for management of systolic hypertension in patients with metabolic syndrome.

The Blood Pressure-Lowering Effect of 20-HETE Blockade in Cyp4a14(-/-) Mice Is Associated with Natriuresis

20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE) has been linked to pro-hypertensive and anti-hypertensive actions through its ability to promote vasoconstriction and inhibit Na transport in the ascending limb of the loop of Henle, respectively. In this study, we assessed the effects of 20-HETE blockade on blood pressure, renal hemodynamics, and urinary sodium excretion in Cyp4a14(-/-) male mice, which display androgen-driven 20-HETE-dependent hypertension. Administration of 2,5,8,11,14,17-hexaoxanonadecan-19-yl 20-hydroxyicosa-6(Z),15(Z)-dienoate (20-SOLA), a water-soluble 20-HETE antagonist, in the drinking water normalized the blood pressure of male Cyp4a14(-/-) hypertensive mice (±124 vs. ±153 mmHg) while having no effect on age-matched normotensive wild-type (WT) male mice. Hypertension in Cyp4a14(-/-) male mice was accompanied by decreased renal perfusion and reduced glomerular filtration rates, which were corrected by treatment with 20-SOLA. Interestingly, Cyp4a14(-/-) male mice treated with 20-SOLA displayed increased urinary sodium excretion that was paralleled by the reduction of blood pressure suggestive of an antinatriuretic activity of endogenous 20-HETE in the hypertensive mice. This interpretation is in line with the observation that the natriuretic response to acute isotonic saline loading in hypertensive Cyp4a14(-/-) male mice was significantly impaired relative to that in WT mice; this impairment was corrected by 20-SOLA treatment. Hence, endogenous 20-HETE appears to promote sodium conservation in hypertensive Cyp4a14(-/-) male mice, presumably, as a result of associated changes in renal hemodynamics and/or direct stimulatory action on tubular sodium reabsorption.

0.95 W high-repetition-rate, picosecond 335 nm laser based on a frequency quadrupled, diode-pumped Nd:YVO(4) MOPA system

An efficient all-solid-state picosecond (ps) ultraviolet (UV) laser at 335 nm was demonstrated based on frequency quadrupling of a mode-locked 1342 nm MOPA system. An output power of 0.95 W was obtained under a fundamental wave power of 16.38 W, corresponding to a conversion efficiency of 5.8% from infrared to UV. The repetition rate and pulse duration were 77 MHz and 20.2 ps, respectively. The beam quality factor M(2) was measured to be 1.56. This is, to the best of our knowledge, the highest output power at 335 nm.

[Nested case-control study on associated factors for anemia during pregnancy]

Objective: To explore the related factors of anemia during pregnancy and provide scientific evidence for the primary prevention of anemia during pregnancy. Methods: The pregnant women (≤12 pregnant weeks) who received the first pregnancy care in a local medical institution in Hunan province from June 2013 to November 2014 were included in this cohort study, and for them anemia had been excluded by physical examination. Baseline survey and follow up till childbirth were conducted for them. A queue-based nested case-control study (1 ∶ 2) was conducted (380 pregnant women with anemia detected in this study as case group, 760 pregnant women without anemia randomly selected and matched by age, habitual residence during pregnancy as control group. And t test, χ(2) test and logistic regression analysis were conducted to identify related factors of anemia during pregnancy. Results: Multivariate logistic regression analysis indicated that low family annual income level (net income) (OR=2.08, 95%CI: 1.22-3.59), low educational level (OR=2.09, 95%CI: 1.22-3.59), pre-pregnancy perm/hair dye (OR=2.23, 95%CI: 1.63-3.05), early pregnancy vomiting (OR=2.51, 95%CI: 1.56-4.03) were the risk factors for anemia during pregnancy. Intake of vitamin and trace element supplements (OR=0.69, 95%CI: 0.50-0.94), frequent meat, fish, shrimp, egg intakes (OR=0.68, 95%CI: 0.49-0.92), frequent soy milk, milk intakes (OR=0.51, 95%CI: 0.27-0.95) were the protective factors for anemia during pregnancy. Conclusion: A number of factors, such as family annual income level, education level, poisonous and harmful material contact, pregnancy reaction, nutrition, are related to the incidence of anemia during pregnancy, it is necessary to take preventive measures to reduce the incidence of anemia during pregnancy.

[Features of peripheral nerve injuries in workers exposed to vibration: an analysis of 197 cases]

Objective: To investigate the features of peripheral nerve injuries in workers exposed to vibration. Methods: A total of 197 male workers [median age: 34 years (21-50 years) ; median working years of vibration exposure: 7.3 years (1-20 years) ] engaged in grinding in an enterprise were enrolled. Their clinical data and electromyography results were analyzed to investigate the features of peripheral nerve impairment. Results: Of all workers, 96 (48.73%) had abnormal electromyography results. Of all workers, 88 (44.7%) had simple mild median nerve injury in the wrist, who accounted for 91.7% (88/96) of all workers with abnormal electromy-ography results. Six workers had ulnar nerve injury, superficial radial nerve injury, or/and superficial peroneal nerve injury and accounted for 6.3% of all workers with abnormal electromyography results. Of all workers, 88 had a reduced amplitude of median nerve sensory transduction, and 28 had slowed median nerve sensory transduction. A total of 46 workers were diagnosed with occupational hand-arm vibration disease and hospitalized for treatment. They were followed up for more than 4 months after leaving their jobs, and most of them showed improvements in neural electromyography results and returned to a normal state. Conclusion: Workers exposed to vibration have a high incidence rate of nerve injury in the hand, mainly sensory function impairment at the distal end of the median nerve, and all injuries are mild peripheral nerve injuries. After leaving the vibration job and being treated, most workers can achieve improvements and return to a normal state.

[Association between inflammation activity of left atrial epicardial adipose tissue measured by 18F-FDG PET/CT and atrial fibrillation]

Objective: To explore the association between inflammation activity of left atrial epicardial adipose tissue (LA-EAT) measured by ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and atrial fibrillation (AF). Methods: A total of 78 patients with AF, who underwent ¹⁸F-FDG PET/CT in the Nuclear Medicine Department of the Third Affiliated Hospital of Soochow University due to abnormally elevated levels of tumor indicators or malignant tumors from March 2018 to December 2019, were enrolled in this retrospective study. According to the examination date of PET/CT and basic characteristics of AF patients (gender, age), a 1∶1 propensity score matching was used to enroll a non-AF control group (78 patients). The maximum standard uptake value of left atrial epicardial tissue (LA-EAT FDG SUV_max) and total EAT volume (V-EAT) were measured by ¹⁸F-FDG PET/CT. Left ventricular ejection fraction (LVEF) and left atrial diameter (LAD) were obtained by echocardiography. Blood lipids and biomarkers of inflammation were measured. The differences of clinical data and EAT-related indicators were compared between the AF group and control group. Logistic multivariate regression analysis was used to determine the related factors of AF. Then the receiver operating characteristic (ROC) curve was used to determine the cutoff value of LA-EAT FDG SUV_max on the diagnosis of AF. Univariate and multivariate logistic regression analysis were used to analyze the relationship between the increase of LA-EAT FDG SUV_max and AF. Results: The age was (66.9±10.2) years and there were 55 males (70.5%) in the AF group. The age was (66.9±8.0) years, and there were 52 males (66.7%) in the control group (both P>0.05). The LAD ((44.2±5.8) mm vs. (35.4±4.4) mm), V-EAT ((122.1±42.0) cm³ vs. (91.6±34.5) cm³), and LA-EAT FDG SUV_max ((1.6±0.3) vs. (1.4±0.2)) values were significantly higher, while LVEF ((60.1±4.7)% vs. (63.9±2.9)%) was lower in the AF group than in the control group (P all<0.001). Multivariate logistic regression analysis showed that LAD (OR=1.340, 95%CI 1.195-1.502), V-EAT (OR=1.016, 95%CI 1.001-1.031), and LA-EAT FDG SUV_max (OR=1.375, 95%CI 1.095-1.723) were positively correlated with AF, LVEF (OR=0.781, 95%CI 0.659-0.926) was negatively correlated with AF(P all<0.05). The area under the ROC curve of LA-EAT FDG SUV_max for diagnosis of AF was 0.680 (95%CI 0.597-0.764, P<0.001), and the best cut-off value was 1.415 with a sensitivity of 65.4% and specificity of 61.5%. After adjusting for high-density lipoprotein cholesterol, LVEF, LAD and V-EAT, LA-EAT FDG SUV_max≥1.415 was independently associated with AF (OR=2.982, 95%CI 1.122-7.926, P=0.010). Conclusions: The inflammatory activity of LA-EAT measured by ¹⁸F-FDG PET/CT is an independent risk factor of AF, and the increased inflammatory activity of LA-EAT is positively correlated with AF.

Utilities of environmental radioactivity tracers in assessing sequestration potential of carbon in the coastal wetland ecosystems

Demand for accurate estimation of coastal blue carbon sequestration rates in a regular interval has recently surged due to the increasing awareness of nature-based climate solutions to alleviate adverse impacts stemming from the recent global warming. The robust estimation method is, however, far from well-established. The international community requires, moreover, to quantify its effect of "management." This article tries to provide the environmental isotope community with basic biophysical features of coastal blue carbon ecosystems to identify a suitable set of environmental isotopes for promoting coastal ocean-based climate solutions. This article reviews (i) the primary biophysical characteristics of coastal blue carbon ecosystems and hydrology, (ii) their consequential impact on the accumulation and preservation of organic carbon (OC) in the sediment column, (iii) suitable environmental isotopes to quantifying the sedimentary organic carbon accumulation, outwelling of the carbon-containing byproducts of decomposition of biogenic organic matter and acid neutralizing alkalinity produced in situ sediment to the offshore. Above-ground biomass is not cumulative over the years except for mangrove forests within coastal blue carbon systems. Non-gaseous carbon sequestration and loss occur mainly as a form of sediment organic carbon (SOC) and dissolved carbon in an intertidal and subtidal bottom sediment body in a slow, patchy, and dispersive way, on which this article focuses. Investigating environmental radionuclides is probably the most cost-effective effort to contribute to defining the offshore spatial extent of coastal blue carbon systems except for seagrass beds (e.g., Ra isotopes), to quantify millimeter per year scale carbon accretion and loss within the systems (e.g., 7Be, 210Pb) and a liter per meter of coastline per a day scale water movement from the systems (Ra isotopes). A millimeter-scale spatial and an annual (or less) time-scale resolution offered by the use of environmental isotopes would equip us with a novel tool to enhance the carbon storage capacity of the coastal blue carbon system.

[An adolescent with Hashimoto's encephalopathy after surgery and ¹³¹I radiotherapy for papillary thyroid carcinoma: one case report]

Hashimoto's encephalopathy is a rare brain disease. Its etiology is still unknown. In this paper, we reported a 15-year-old female patient underwent total thyroidectomy and lymph node dissection, due to a multifocal papilliferous carcinoma of the right lobus. Forty-two days after surgery, the patient was treated by ¹³¹I radiotherapy in another hospital and begun to have a headache after 48 hours. At last, the patient was diagnosed by HE on the basis of all considerations. She recovered from by i.v. Immunoglobulin. Till now, the patient has not relapsed for more than 4 years follow-up.

Abstract 295: The Role of 20-HETE in the Control of Prostate Cancer Tumor Vasculature

20-Hydroxyeicosatetraenoic acid (20-HETE) is a cytochrome P450-derived arachidonic acid metabolite endowed with vasoconstrictor. Recent reports documented that 20-HETE synthesis inhibitors decrease the growth of glioma and renal cell carcimona, and that urinary 20-HETE levels are significantly elevated in prostate cancer patients. These reports led us to investigate the role of 20-HETE in the regulation of blood flow to prostate cancer tumors. First, we compared 20-HETE levels in prostate cancer cell line-LNCaP and normal prostate epithelial cells. Cultured LNCaP cells produced high levels of 20-HETE (566±139 pg/mg protein), whereas 20-HETE production was undetectable in normal prostate epithelial cells. Second, subcutaneous tumors were induced in balb/c nude mice by injection of LNCaP cells, followed by assessment of 20-HETE in both tumors and isolated tumor vessels. We found that LNCaP cell-derived tumors had high levels of 20-HETE (425±97 pg/mg protein), while the level in isolated tumor vessels was undetectable. Third, we used laser-doppler flowmetry to evaluate whether tumor-derived 20-HETE influences tumor blood flow and vessel diameter in vivo. Topical application of the 20-HETE antagonist 20-6,15-HEDE (1 mM) to tumor vessels in vivo increased blood flow by 1.81±0.34-fold and vessel diameter by 1.286±0.133-fold, which responses were reversed by topical application of 20-HETE in a dose-dependent manner. We conclude that LNCaP cell-derived tumors produce 20-HETE which, in turn, promotes vasoconstriction leading to reduction of tumor blood flow.

Toward the validation of aneusomy detection by fluorescence in situ hybridization in bladder cancer: comparative analysis with cytology, cytogenetics, and clinical features predicts recurrence and defines clinical testing limitations

Fluorescence in situ hybridization (FISH) is regarded as a potential new tool for the clinical management of bladder cancer that works by detecting cytogenetic aberrations in noncycling, exfoliated cells from bladder irrigations. However, clinical validation steps must be addressed to define the true predictive potential in a clinical setting. Toward the validation of FISH with the use of bladder washings and prior to incorporation into a large, prospective clinical trial, a pilot study was designed to determine its clinical potential, define testing limitations, optimize a panel of probes specific for bladder cancer detection, and outline protocol/data collection parameters. Correlations with standard cytogenetics and clinicopathological features of bladder cancer were investigated. Exfoliated cells obtained from benign bladder washings served as normal controls. The results of this pilot study suggest the following: (a) FISH and cytology are complementary testing procedures; however, the FISH data provided valuable ploidy and specific genotypic information for recurrent tumors in "suspicious" cases; (b) chromosomal aberrations defined by FISH are associated with tumor grade and stage (i.e., simple numerical aberrations were associated with low-grade tumors, and high-grade and invasive tumors exhibited multiple, nonrandom chromosomal aberrations and vast intratumor heterogeneity); (c) somatic pairing or homologous centromeric association can give a false-positive result and appears to be linked to prior therapy; (d) dual hybridization with reference gene-specific probes must be used to control for somatic pairing; and (e) focal, deep muscle invasive lesions, with no surface exposure, may yield false-negative results. The data suggest that FISH analysis, with the use of cells isolated from bladder washings, is a powerful technique holding promise for early cancer detection, monitoring treatment outcome, and predicting recurrence of disease.

Simultaneous detection of multiple genetic aberrations in single cells by spectral fluorescence in situ hybridization

Spectral fluorescence in situ hybridization (S-FISH) is a novel molecular cytogenetic approach that detects multiple disease-specific chromosomal aberrations in interphase nuclei using combinatorial fluorescence and digital imaging microscopy. A panel of six centromeric probes for chromosomes 7, 8, 9, 10, X, and Y, using a unique two-dye combination of four fluorophores, was developed to assess ploidy in breast tumors, bladder washings, and leukemia. Validation of S-FISH was performed by classic cytogenetics when metaphases were available or by standard fluorescence in situ hybridization (FISH) analyses. S-FISH identified clonal aberrations in newly diagnosed breast tumors and recurrent bladder cancer and revealed minimal residual disease in hyperdiploid acute lymphocytic leukemia, providing "proof of concept." Like standard FISH, aberrations were identified in poor growth/no growth specimen at the single cell level; however, S-FISH provided increased sensitivity over standard FISH by surveying six genetic targets instead of one or two. Disadvantages of the current assay include labor intensive screening and interpretative challenges with signal overlap in highly aneuploid samples and focal plane distortions. S-FISH appears to be a sensitive oncology assay with significant clinical application for early detection of new or reemerging clones, allowing for earlier therapeutic intervention and development of probe panels for individualized therapy.