Miracle-dz/UniFAR-FTUs huggingface dataset:
Heterometric regulation and calcium sensitivity of the infarcted rat heart.

1. The surviving hypertrophied muscle remaining after myocardial infarction in rats is less sensitive to extracellular Ca2+ than the normal myocardium. Since the inotropic effect of Ca2+ is modulated by sarcomere length, the present study was undertaken to determine if Ca2+ desensitization of infarcted left ventricles (LV) can be modulated by increasing the diastolic pressure (DP). 2. Rats submitted to left coronary artery ligation (N = 11) or sham-operation (N = 9) were killed 8-10 days later and their hearts perfused by the Langendorff technique. A balloon was introduced into the LV cavity to measure the isovolumic systolic pressure (ISP) produced by DP changes (0 to 25 mmHg) at three Ca2+ concentrations (0.8, 1.25 and 2.5 mM). 3. In control hearts submitted to a DP of 5 mmHg, the ISP increased from 36 +/- 3 to 63 +/- 4 and to 74 +/- 4 mmHg as external Ca2+ was changed from 0.8 to 1.25 and to 2.5 mM, respectively. In contrast, in infarcted hearts submitted to the same DP and Ca2+ concentrations, the ISP increased from 19 +/- 2 to 26 +/- 2 and to 27 +/- 3 mmHg. The depressed response to Ca2+ was not modified by increasing DP up to 25 mmHg, the greatest DP tested. At this DP, ISP increased from 75 +/- 4 to 103 +/- 5 and to 114 +/- 5 mmHg in control hearts and from 45 +/- 2 to 54 +/- 3 and to 55 +/- 4 mmHg in infarcted hearts. (ABSTRACT TRUNCATED AT 250 WORDS)
Fast activation and inactivation of inositol trisphosphate‐evoked Ca2+ release in rat cerebellar Purkinje neurones.

1. Calcium release from stores via inositol trisphosphate (InsP3) activation of intracellular Ca2+ receptor‐channels is thought to have a role in regulating the excitability of cerebellar Purkinje neurones. The kinetic characteristics of InsP3 receptor activation in Purkinje neurones are reported here. 2. InsP3 was applied by flash photolysis of caged InsP3 during whole‐cell patch clamp. Ca2+ flux into the cytosol was measured with a low‐affinity fluorescent Ca2+ indicator and by activation of Ca(2+)‐dependent membrane conductance. 3. InsP3 produced Ca2+ release from stores with an initial well‐defined delay (mean, 85 ms at 10 microM InsP3), which decreased to less than 20 ms at high InsP3 concentrations. 4. The rate of rise of free [Ca2+], which provides a measure of Ca2+ efflux and InsP3 receptor activation, increased with increasing InsP3 concentration in each cell and had a high absolute value of up to 1400 microM s‐1 at 40 microM InsP3. The period of fast efflux was brief, inactivating in 25 ms at low and in 9 ms at high InsP3 concentration. 5. Peak free [Ca2+] was high (mean, 23 microM with a pulse of 40 microM InsP3) and increased with InsP3 concentration up to 80 microM InsP3 tested here. 6. Experiments with a flash‐released, stable 5‐thio‐InsP3 confirm that the low InsP3 sensitivity of Purkinje neurones does not result from metabolism of InsP3. 7. The low functional affinity and fast activation by InsP3 suggest a difference in InsP3 receptor properties from non‐neuronal cells tested in the same way. The large Ca2+ efflux and high peak [Ca2] probably result from high InsP3 receptor‐channel density. 8. Elevated cytosolic [Ca2+] produced by Ca2+ influx through plasmalemmal Ca2+ channels strongly suppressed InsP3‐evoked Ca2+ release from stores. Rapid termination of InsP3‐evoked efflux results mainly from inhibition by high [Ca2+]. 9. The fast InsP3 activation kinetics and rapid, strong inactivation by Ca2+ influx suggest that interactions between InsP3‐mediated and membrane Ca2+ signalling could occur on a time scale compatible with neuronal excitation.
Signaling requirements for translocation of P‐Rex1, a key Rac2 exchange factor involved in chemoattractant‐stimulated human neutrophil function

PI 3,4,5‐trisphosphate [PI(3,4,5)P3; PIP3]‐dependent Rac exchanger 1 (P‐Rex1) is a Rac‐specific guanine nucleotide exchange factor abundant in neutrophils and myeloid cells. As a selective catalyst for Rac2 activation, P‐Rex1 serves as an important regulator of human neutrophil NADPH oxidase activity and chemotaxis in response to a variety of extracellular stimuli. The exchange activity of P‐Rex1 is synergistically activated by the binding of PIP3and βγ subunits of heterotrimeric G proteins in vitro, suggesting that the association of P‐Rex1 with membranes is a prerequisite for cellular activation. However, the spatial regulation of endogenous P‐Rex1 has not been well defined, particularly in human neutrophils activated through G protein‐coupled receptors. Upon stimulation of neutrophil chemoattractant receptors, we observed that P‐Rex1 translocated from cytoplasm to the leading edge of polarized cells in a G protein βγ subunit‐ and PIP3‐dependent manner, where it colocalized with F‐actin and its substrate, Rac2. Redistribution of P‐Rex1 to the leading edge was also dependent on tyrosine kinase activity and was modulated by cell adhesion. Furthermore, we observed that activation of cAMP‐dependent protein kinase A (PKA), which phosphorylates and inactivates P‐Rex1, inhibited its translocation. Our data indicate that endogenous P‐Rex1 translocates to areas of Rac2 and cytoskeletal activation at the leading edge in response to chemoattractant stimuli in human neutrophils and that this translocation can be negatively modulated by activation of PKA and by cell adhesion.
Potentially functional polymorphisms in IL‐23 receptor and risk of esophageal cancer in a Chinese population

Interleukin‐23 (IL‐23)/IL‐23 receptor (IL‐23R) is essential for Th17 cell‐mediated immune response, involved in autoimmune diseases and cancer pathogenesis. Two potentially functional genetic single nucleotide polymorphisms (SNPs; IL‐23R rs6682925 T>C and rs1884444 T>G) were found to contribute to cancer susceptibility. In our study, we conducted a case–control study including 1,645 patients with esophageal cancer and 1,694 cancer‐free controls in a Chinese population to assess the association between the two SNPs and the risk of esophageal cancer. We found that IL‐23R rs6682925 TC/CC and rs1884444 TG/GG variant genotypes were associated with significantly increased risk of esophageal cancer [rs1884444: adjusted odds ratio (OR) = 1.16, 95% confidence intervals (CIs) =1.01–1.33; rs6682925: adjusted OR = 1.23, 95% CIs = 1.07–1.42], compared to their corresponding wild‐type homozygotes. Furthermore, the increased risks associated with the two SNPs were independent from smoking and alcohol drinking status. These findings indicated that genetic variants in IL‐23R may contribute to esophageal cancer risk in our Chinese population.
New insights into the control of neurotrophic growth factor receptor signaling: Implications for nervous system development and repair

Neurotrophic growth factors control neuronal development by activating specific receptor tyrosine kinase positive signaling pathways, such as Ras‐MAPK and PI3K‐Akt cascades. Once activated, neurotrophic factor receptors also trigger a cascade of molecular events, named negative receptor signaling, that restricts the intensity of the positive signals and modulates cellular behavior. Thus, to avoid signaling errors that ultimately could lead to aberrant neuronal physiology and disease, negative signaling mechanisms have evolved to ensure that suitable thresholds of neuronal stimulation are achieved and maintained during right periods of time. Recent findings have revealed that neurotrophic factor receptor signaling is tightly modulated through the coordinated action of many different protein regulators that limit or potentiate signal propagation in spatially and temporally controlled manners, acting at specific points after receptor engagement. In this review, we discuss progress in this field, highlighting the importance of these modulators in axonal growth, guidance, neural connectivity, and nervous system regeneration.
L-743, 726 (DMP-266): a novel, highly potent nonnucleoside inhibitor of the human immunodeficiency virus type 1 reverse transcriptase

The clinical benefit of the human immunodeficiency virus type 1 (HIV-1) nonnucleoside reverse transcriptase (RT) inhibitors (NNRTIs) is limited by the rapid selection of inhibitor-resistant viral variants. However, it may be possible to enhance the clinical utility of this inhibitor class by deriving compounds that express both high levels of antiviral activity and an augmented pharmacokinetic profile. Accordingly, we developed a new class of NNRTIs, the 1, 4-dihydro-2H-3, 1-benzoxazin-2-ones. L-743, 726 (DMP-266), a member of this class, was chosen for clinical evaluation because of its in vitro properties. The compound was a potent inhibitor of the wild-type HIV-1 RT (Ki = 2.93 nM) and exhibited a 95% inhibitory concentration of 1.5 nM for the inhibition of HIV-1 replicative spread in cell culture. In addition, L-7743, 7726 was found to be capable of inhibiting, with 95% inhibitory concentrations of < or = 1.5 microM, a panel of NNRTI-resistant mutant viruses, each of which expressed a single RT amino acid substitution. Derivation of virus with notably reduced susceptibility to the inhibitor required prolonged cell culture selection and was mediated by a combination of at least two RT amino acid substitutions. Studies of L-743, 726 in rats, monkeys, and a chimpanzee demonstrated the compound's potential for good oral bioavailability and pharmacokinetics in humans.
Gefitinib inhibits the cross‐talk between mesenchymal stem cells and prostate cancer cells leading to tumor cell proliferation and inhibition of docetaxel activity

Increasing evidence suggests that bone marrow derived mesenchymal stem cells (BM‐MSCs) are recruited into the stroma of developing tumors where they contribute to progression by enhancing tumor growth and metastasis, or by inducing anticancer‐drug resistance. Prostate cancer cells secrete ligands of epidermal growth factor receptor (EGFR) and EGFR signaling could play an important role in the cross‐talk between mesenchymal stem cells and prostate cancer cells. In this study, we showed that treatment of human primary MSCs with conditioned medium (CM) derived from the bone metastatic PC3 carcinoma cells (PC3‐CM) resulted in: a significant activation of EGFR; increased proliferation; increased osteoblastic but decreased adipocitic differentiation; inhibition of senescence induced by serum starvation; increased CCL5 secretion. These activities were significantly inhibited in the presence of the EGFR tyrosine kinase inhibitor gefitinib. PC3‐CM directly inhibited osteoclastogenesis as well as the ability of osteoblasts to induce osteoclast differentiation. The increased MSCs migration by PC3‐CM and PC3 cells was partially mediated by CCL5. MSC‐CM increased the formation of colonies by PC3 cells and inhibited the anti‐proliferative activity of Docetaxel. Activation of EGFR expressed on MSCs by PC3‐CM enhanced their capability to increase PC3 cells proliferation and to inhibit Docetaxel activity. These findings, by showing that the tumor‐promoting interactions between PC3 cells and MSCs are mediated, at least in part, by EGFR, suggest a novel application of the EGFR‐tyrosine kinase inhibitors in the treatment of prostate cancer. J. Cell. Biochem. 114: 1135–1144, 2013. © 2012 Wiley Periodicals, Inc.
Prevention of Bleeding After Islet Transplantation: Lessons Learned from a Multivariate Analysis of 132 Cases at a Single Institution

Islet transplantation is being offered increasingly for selected patients with unstable type 1 diabetes. Percutaneous transhepatic portal access avoids a need for surgery, but is associated with potential risk of bleeding. Between 1999 and 2005, we performed 132 percutaneous transhepatic islet transplants in 67 patients. We encountered bleeding in 18/132 cases (13.6%). In univariate analysis, the risk of bleeding in the absence of effective track ablation was associated with an increasing number of procedures (2nd and 3rd procedures with an odds ratio (OR) of 9.5 and 20.9, respectively), platelets count <150 000 (OR 4.4), elevated portal pressure (OR 1.1 per mm Hg rise), heparin dose ≥45 U/kg (OR 9.8) and pre‐transplant aspirin (81 mg per day) (OR 2.6, p = 0.05). A multivariate analysis further confirmed the cumulative transplant procedure number (p < 0.001) and heparin dose ≥45 U/kg (p = 0.02) as independent risk factors for bleeding. Effective mechanical sealing of the intrahepatic portal catheter tract with thrombostatic coils and tissue fibrin glue completely prevented bleeding in all subsequent procedures (n = 26, p = 0.02). We conclude that bleeding after percutaneous islet implantation is an avoidable complication provided the intraparenchymal liver tract is sealed effectively.
Electroretinographic Oscillatory Potentials Predict Progression of Diabetic Retinopathy: Preliminary Report

• The oscillatory potential (OP) amplitudes of the electroretinogram (ERG) were determined in a group of 85 diabetic patients entering the Early Treatment Diabetic Retinopathy Study (ETDRS). The rate of progression among nonphotocoagulated eyes to the Diabetic Retinopathy Study high-risk characteristics (DRS-HRC) during a ten- to 40-month follow-up period was determined. Progression occurred in 19 of 85 eyes at risk. Those eyes with abnormal OP amplitudes (≤75 μV) at study entry had a tenfold higher rate of progression to DRS-HRC than did eyes with normal amplitudes (>75 μV). Although the level of retinopathic severity at study entry was a significant factor in the rate of subsequent progression, the amplitudes of the OPs remained a significant risk factor even after correcting the initial retinopathic level. The ERG seems to be a useful clinical tool in predicting the rate of progression of diabetic retinopathy. The reduction in OP amplitudes probably is a quantitative measure of the degree of overall inner layer retinal ischemia.
Lipidomic analysis of the retina in a rat model of Smith–Lemli–Opitz syndrome: alterations in docosahexaenoic acid content of phospholipid molecular species

Smith–Lemli–Opitz syndrome (SLOS) is a complex hereditary disease caused by an enzymatic defect in the last step of cholesterol biosynthesis. Progressive retinal degeneration occurs in an AY9944‐induced rat model of SLOS, with biochemical and electroretinographic hallmarks comparable with the human disease. We evaluated alterations in the non‐sterol lipid components of the retina in this model, compared with age‐matched controls, using lipidomic analysis. The levels of 16:0–22:6 and 18:0–22:6 phosphatidylcholine molecular species in retinas were less by > 50% and > 33%, respectively, in rats treated for either 2 or 3 months with AY9944. Relative to controls, AY9944 treatment resulted in > 60% less di‐22:6 and > 15% less 18:0–22:6 phosphatidylethanolamine molecular species. The predominant phosphatidylserine (PS) molecular species in control retinas were 18:0–22:6 and di‐22:6; notably, AY9944 treatment resulted in > 80% less di‐22:6 PS, relative to controls. Remarkably, these changes occurred in the absence of n3 fatty acid deficiency in plasma or liver. Thus, the retinal lipidome is globally altered in the SLOS rat model, relative to control rats, with the most profound changes being less phosphatidylcholine, phosphatidylethanolamine, and PS molecular species containing docosahexaenoic acid (22:6). These findings suggest that SLOS may involve additional metabolic compromise beyond the primary enzymatic defect in the cholesterol pathway.
[Epidural midazolam with saline--optimal dose for postoperative pain].

Optimal dose of epidural midazolam with saline for postoperative pain relief was investigated. Forty three patients for upper abdominal surgery were divided into 5 groups. Each group had either 10 ml saline only (saline group), 10 ml saline + midazolam 0.025 mg.kg-1 (0.025 group), 10 ml saline + midazolam 0.05 mg.kg-1 (0.05 group), 10 ml saline + midazolam 0.075 mg.kg-1 (0.075 group), or 10 ml saline + midazolam 0.1 mg.kg-1 (0.1 group) administered epidurally for complaint of postoperative pain. Blood pressure (BP), heart rate (HR), respiratory rate (RR) and sedation score (SS) were monitored for 120 minutes, and the time interval for next analgesics (TNA) was checked. In each group, BP was unchanged compared with preinjection level. HR changes were less in 0.05 and 0.1 group than in others. RR changes were less in 0.025 and 0.05 group than in others. Optimal SSs were obtained in 0.025 and 0.05 groups. In 0.075 and 0.1 groups, many patients fell into complete sleep (not responded to verbal command). TNA was about 2 hours in 0.025 and 0.05 groups, over 6 hours in 0.075 and 0.1 groups. Complete sleep was the cause of long TNA in 0.075 and 0.1 groups. It was concluded that optimal dose of epidural midazolam with saline 10 ml was 0.05 mg.kg-1 for postoperative pain relief after upper abdominal surgery.
Optical Imaging Biomarkers of Drug-Induced Vascular Injury

Drug-induced vascular injury (DIVI), defined as arterial medial degeneration/necrosis usually associated with perivascular inflammation, is frequently observed in the mesenteric arteries of rats but the relevance to humans remains a hurdle for drug development. Here, we describe the evaluation of commercially available optical imaging biomarkers using a rat DIVI model. Male Sprague Dawley rats were administered 10 mg/kg/day of a proprietary soluble guanylate cyclase activator (sGCa). Optical agents, AngioSense for the detection of vessel permeability, MMPSense for the detection of activated matrix metalloproteinases (MMPs), and IntegriSense for the detection of αvβ3 integrin, were injected via tail vein 24 hours before fluorescence (FL) ex vivo imaging. Imaging found a statistically significant difference in FL from all optical agents between treated and vehicle groups (p < .05). Mesenteric arteries were further analyzed by histopathology, flow cytometry, and immunohistochemistry. Histopathology confirmed perivascular inflammation and/or arterial medial degeneration in the sGCa-treated animals. Flow cytometry of digested arteries revealed myeloid cells as a main source of MMPSense signal. Immunohistochemical analysis further identified elevated MMP-9 expression within arterial walls and surrounding tissue of treated animals. Together, these data demonstrate that MMPSense and AngioSense are sensitive optical imaging biomarkers for the quantification of DIVI in rat mesenteric arteries.
The late effects of radiation on lifespan, lymphocyte proliferation and p53 haplodeficiency in mice

Purpose: We investigated the effect of irradiation on the lifespan of eight-week-old mice, the number of lymphocytes in bone marrow and the levels of p53 protein expression in the splenocytes. Methods and materials: Eight-week-old mice, wild-type p53 (p53+/+) and heterozygous p53 (p53+/−), were irradiated with 3 Gy. The cell numbers and cell cycle phases of bone marrow cells were determined by flow cytometry. The splenocyte proliferation was evaluated by a fluorescent cell viability assay. The p53 expression was evaluated by Western blotting. Results: The lifespan of the irradiated mice was shorter than that of the non-irradiated mice. In irradiated 72-week-old p53+/+ mice and 56-week-old p53+/− mice, the number of lymphocytes in bone marrow decreased as compared to that in the non-irradiated mice. In 56-week-old p53+/− mice, the S- and G2/M-phases of lymphocytes in the irradiated mice were increased compared to that in the non-irradiated mice. The splenocyte proliferation in p53+/+ mice decreased with age, and the proliferation in the irradiated mice was much lower than that in the non-irradiated mice. In 72-week-old p53+/+ mice after re-irradiation, the p53 protein expression in the splenocytes of the irradiated mice was delayed as compared to those from the non-irradiated mice. Conclusion: We suggest that the decrease in the number of lymphocytes in bone marrow and the delayed p53 expression in splenocytes from the irradiated mice are related to the shortened lifespan after irradiation at a young age.
Economic analysis of alternative applications of an algal production system

Title of Document: ECONOMIC ANALYSIS OF ALTERNATIVE APPLICATIONS OF AN ALGAL PRODUCTION SYSTEM Michelle Marie Weber, Master of Science, 2013 Directed By: Professor Patrick C. Kangas Department of Environmental Science & Technology A variety of different best management practices are being studied to reduce nutrient pollution in the Chesapeake Bay. The algal turf scrubberTM (ATS) effectively removes nutrients from Bay waters in experimental trials but there is no large-scale applications in the Chesapeake Bay watershed. The purpose of this project was to conduct an economic analysis of the ATS technology to determine the feasibility for nutrient removal across the Bay landscape. Baseline data for the analysis were extrapolated from several small-scale experimental trials of the ATS. The analysis included scaled costs along with benefits from nutrient trading credits, bio-product values of biofuel production, oxygen from photosynthesis and fertilizer value of nutrients taken up in algal growth. Six operating scenarios were analyzed through various cost analyses. The results indicate that the ATS technology can be economically viable under certain conditions and can be complementary to other best management practices for restoration of water quality in the Bay. ECONOMIC ANALYSIS OF ALTERNATIVE APPLICATIONS OF AN ALGAL PRODUCTION SYSTEM
Regulation of intracellular potassium in mesangial cells: a fluorescence analysis using the dye, PBFI.

We investigated the regulatory transport processes that maintain intracellular K+ homeostasis in cultured rat glomerular mesangial cells (MCs). Intracellular K+ concentration ([K+]i) of quiescent MCs, passages 3-8, grown to subconfluence on glass cover slips, was assessed by spectrofluorometry using the K(+)-sensitive dye, K(+)-binding benzofuran isophthalate (PBFI). Serum-starved MCs were incubated at 37 degrees C in 5 microM PBFI for 90 min. Excitation ratios of luminescences at 340 and 380 nm, measured at a constant emission at 500 nm, were used to determine [K+]i. Ionophores valinomycin and nigericin were used to clamp [K+]i to known [K+]o and thereby obtain an intracellular calibration of dye. Dependence of fluorescence ratio on [K+]i conformed to Michaelis-Menten behavior, with a Km of 113 mM (n = 40). PBFI retains its sensitivity to alterations in [K+]i with pH change (pHi from 6.5 to 7.5) but is relatively insensitive when intracellular Na+ is greater than 75 mM and cell osmolarity exceeds 500 mM. Normal resting [K+]i for all experiments was determined in MCs to be 102 +/- 7 mM (n = 81) in a HCO3(-)-free HEPES-buffered solution. When MCs were exposed to ouabain, [K+]i fell to 48 +/- 6 mM and did not recover, suggesting presence of Na(+)-K(+)-ATPase. When MCs were exposed to furosemide, [K+]i transiently declined to 58 +/- 11 mM, which was followed by a rapid recovery to near steady state, indicating additional presence of Na(+)-K(+)-Cl- cotransporter. Recovery was completely abolished when MCs were exposed to ouabain. (ABSTRACT TRUNCATED AT 250 WORDS)