Recent Research Articles from UNTHSC

Syndicate content NCBI pubmed
NCBI: db=pubmed; Term="University of North Texas Health Science Center"[All Fields] OR "Univ. of North Texas Health Science Center"[All Fields] OR "UNT Health Science Center"[All Fields] OR "Osteopathic Research Center"[All Fields] OR "University of North Texas System College of Pharmacy"[All Fields] OR "UNT System College of Pharmacy"[All Fields] OR "College of Pharmacy, University of North Texas System"[All Fields]
Updated: 51 min 5 sec ago

Resonance energy transfer between fluorescent BSA protected Au nanoclusters and organic fluorophores.

Wed, 08/06/2014 - 4:05am
Related Articles

Resonance energy transfer between fluorescent BSA protected Au nanoclusters and organic fluorophores.

Nanoscale. 2014 Jan 7;6(1):385-91

Authors: Raut S, Rich R, Fudala R, Butler S, Kokate R, Gryczynski Z, Luchowski R, Gryczynski I

Abstract
Bovine serum albumin (BSA) protected nanoclusters (Au and Ag) represent a group of nanomaterials that holds great promise in biophysical applications due to their unique fluorescence properties and lack of toxicity. These metal nanoclusters have utility in a variety of disciplines including catalysis, biosensing, photonics, imaging and molecular electronics. However, they suffer from several disadvantages such as low fluorescence quantum efficiency (typically near 6%) and broad emission spectrum (540 nm to 800 nm). We describe an approach to enhance the apparent brightness of BSA Au clusters by linking them with a high extinction donor organic dye pacific blue (PB). In this conjugate PB acts as a donor to BSA Au clusters and enhances its brightness by resonance energy transfer (RET). We found that the emission of BSA Au clusters can be enhanced by a magnitude of two-fold by resonance energy transfer (RET) from the high extinction donor PB, and BSA Au clusters can act as an acceptor to nanosecond lifetime organic dyes. By pumping the BSA Au clusters using a high extinction donor, one can increase the effective brightness of less bright fluorophores like BSA Au clusters. Moreover, we prepared another conjugate of BSA Au clusters with the near infrared (NIR) dye Dylight 750 (Dy750), where BSA Au clusters act as a donor to Dy750. We observed that BSA Au clusters can function as a donor, showing 46% transfer efficiency to the NIR dye Dy750 with a long lifetime component in the acceptor decay through RET. Such RET-based probes can be used to prevent the problems of a broad emission spectrum associated with the BSA Au clusters. Moreover, transferring energy from BSA Au clusters to Dy750 will result in a RET probe with a narrow emission spectrum and long lifetime component which can be utilized in imaging applications.

PMID: 24201559 [PubMed - indexed for MEDLINE]

Characterization of a new composite PMMA-HA/Brushite bone cement for spinal augmentation.

Tue, 08/05/2014 - 4:05am
Related Articles

Characterization of a new composite PMMA-HA/Brushite bone cement for spinal augmentation.

J Biomater Appl. 2014 Aug 1;

Authors: Aghyarian S, Rodriguez LC, Chari J, Bentley E, Kosmopoulos V, Lieberman IH, Rodrigues DC

Abstract
Calcium phosphate fillers have been shown to increase cement osteoconductivity, but have caused drawbacks in cement properties. Hydroxyapatite and Brushite were introduced in an acrylic two-solution cement at varying concentrations. Novel composite bone cements were developed and characterized using rheology, injectability, and mechanical tests. It was hypothesized that the ample swelling time allowed by the premixed two-solution cement would enable thorough dispersion of the additives in the solutions, resulting in no detrimental effects after polymerization. The addition of Hydroxyapatite and Brushite both caused an increase in cement viscosity; however, these cements exhibited high shear-thinning, which facilitated injection. In gel point studies, the composite cements showed no detectable change in gel point time compared to an all-acrylic control cement. Hydroxyapatite and Brushite composite cements were observed to have high mechanical strengths even at high loads of calcium phosphate fillers. These cements showed an average compressive strength of 85 MPa and flexural strength of 65 MPa. A calcium phosphate-containing cement exhibiting a combination of high viscosity, pseudoplasticity and high mechanical strength can provide the essential bioactivity factor for osseointegration without sacrificing load-bearing capability.

PMID: 25085810 [PubMed - as supplied by publisher]

Erratum to: Pressure cycling technology (PCT) reduces effects of inhibitors of the PCR.

Sun, 08/03/2014 - 4:05am
Related Articles

Erratum to: Pressure cycling technology (PCT) reduces effects of inhibitors of the PCR.

Int J Legal Med. 2014 Aug 1;

Authors: Marshall PL, King JL, Lawrence NP, Lazarev A, Gross VS, Budowle B

PMID: 25082499 [PubMed - as supplied by publisher]

Kinetic comparison of older men and women during walk-to-stair descent transition.

Sun, 08/03/2014 - 4:05am
Related Articles

Kinetic comparison of older men and women during walk-to-stair descent transition.

Gait Posture. 2014 Jul 15;

Authors: Singhal K, Kim J, Casebolt J, Lee S, Han KH, Kwon YH

Abstract
Stair walking is one of the most challenging tasks for older adults, with women reporting higher incidence of falls. The purpose of this study was to investigate the gender differences in kinetics during stair descent transition. Twenty-eight participants (12 male and 16 female; 68.5 and 69.0 years of mean age, respectively) performed stair descent from level walking in a step-over-step manner at a self-selected speed over a custom-made three-step staircase with embedded force plates. Kinematic and force data were combined using inverse dynamics to generate kinetic data for gender comparison. The top and the first step on the staircase were chosen for analysis. Women showed a higher trail leg peak hip abductor moment (-1.0Nm/kg), lower trail leg peak knee extensor moment and eccentric power (0.74Nm/kg and 3.15W/kg), and lower peak concentric power at trail leg ankle joint (1.29W/kg) as compared to men (p<0.05; -0.82Nm/kg, 0.89Nm/kg, 3.83W/kg, and 1.78W/kg, respectively). The lead leg knee eccentric power was also lower in women (p<0.05). This decreased ability to exert knee control during stair descent transition may predispose women to a higher risk of fall.

PMID: 25082325 [PubMed - as supplied by publisher]

The novel histone deacetylase inhibitor thailandepsin A inhibits anaplastic thyroid cancer growth.

Sun, 08/03/2014 - 4:05am
Related Articles

The novel histone deacetylase inhibitor thailandepsin A inhibits anaplastic thyroid cancer growth.

J Surg Res. 2014 Jul;190(1):191-7

Authors: Weinlander E, Somnay Y, Harrison AD, Wang C, Cheng YQ, Jaskula-Sztul R, Yu XM, Chen H

Abstract
BACKGROUND: Anaplastic thyroid cancer (ATC) remains refractory to available surgical and medical interventions. Histone deacetylase (HDAC) inhibitors are an emerging targeted therapy with antiproliferative activity in a variety of thyroid cancer cell lines. Thailandepsin A (TDP-A) is a novel class I HDAC inhibitor whose efficacy remains largely unknown in ATC. Therefore, we aimed to characterize the effect of TDP-A on ATC.
METHODS: Human-derived ATC cells were treated with TDP-A. IC50 was determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) rapid colorimetric assay, and cell proliferation was measured by viable cell count. Molecular mechanisms of cell growth inhibition were investigated by Western blot analysis of canonical apoptosis markers, intrinsic and extrinsic apoptosis regulators, and cell cycle regulatory proteins. Cell cycle staging was determined with propidium iodide flow cytometry.
RESULTS: TDP-A dose- and time-dependently reduced cell proliferation. Increased cleavage of the apoptosis markers Caspase-9, Caspase-3, and poly adenosine diphosphate ribose polymerase were observed with TDP-A treatment. Levels of the intrinsic apoptosis pathway proteins BAD, Bcl-XL, and BAX remained unchanged. Importantly, the extrinsic apoptosis activator cleaved Caspase-8 increased dose-dependently, and the antiapoptotic proteins Survivin and Bcl-2 decreased. Among the cell cycle regulatory proteins, levels of CDK inhibitors p21/WAF1 and p27/KIP increased. Flow cytometry showed that ATC cells were arrested in G2/M phase with diminished S phase after TDP-A treatment.
CONCLUSIONS: TDP-A induces a notable dose- and time-dependent antiproliferative effect on ATC, which is mainly attributed to extrinsic apoptosis with concomitant cell cycle arrest. TDP-A therefore warrants further preclinical and clinical investigations.

PMID: 24679699 [PubMed - indexed for MEDLINE]

Letter to the editor in regard to Peacock, Bruno, and Martin (2012): "the subjective physiological, psychological, and behavioral risk-taking consequences of alcohol and energy drink co-ingestion": misleading results and unjustified conclusions.

Sun, 08/03/2014 - 4:05am
Related Articles

Letter to the editor in regard to Peacock, Bruno, and Martin (2012): "the subjective physiological, psychological, and behavioral risk-taking consequences of alcohol and energy drink co-ingestion": misleading results and unjustified conclusions.

Alcohol Clin Exp Res. 2013 Dec;37(12):2168-70

Authors: Rossheim ME, Suzuki S, Thombs DL

PMID: 23895400 [PubMed - indexed for MEDLINE]

Angiotensin II induces membrane trafficking of natively-expressed Transient Receptor Potential vanilloid type 4 channels in hypothalamic 4B cells.

Sat, 08/02/2014 - 4:06am

Angiotensin II induces membrane trafficking of natively-expressed Transient Receptor Potential vanilloid type 4 channels in hypothalamic 4B cells.

Am J Physiol Regul Integr Comp Physiol. 2014 Jul 30;

Authors: Saxena A, Bachelor M, Park YH, Carreno FR, Nedungadi TP, Cunningham JT

Abstract
Transient receptor potential vanilloid family type 4 (TRPV4) channels are expressed in central neuroendocrine neurons and have been shown to be polymodal in other systems. We previously reported that, in rodent a model of dilutional hyponatremia associated with hepatic cirrhosis, TRPV4 expression is increased in lipid rafts from the hypothalamus and that this effect may be angiotensin dependent. In this study, we utilized the immortalized neuroendocrine rat hypothalamic 4B cell line to more directly test the effects of angiotensin II (Ang II) on TRPV4 expression and function. Our results demonstrate the expression of transcripts for SRY (male genotype), AVP, CRF, TRPV4, and Ang II type 1a and 1b receptor in 4B cells. After a 1 hour incubation in Ang II (100 nM), 4B cells showed increased TRPV4 abundance in the plasma membrane fraction and this effect was prevented by the Ang II type 1 receptor antagonist, Losartan (1 µM) , and by a Src kinase inhibitor, PP2 (10 µM). Radiometric calcium imaging experiments demonstrated that Ang II incubation potentiated TRPV4 agonist (GSK 1016790A, 20 nM) induced calcium influx (Control 18.4 ± 2.8% n=5 and Ang II 80.5 ± 2.4% n=5). This Ang II induced increase in calcium influx was also blocked by 1 µM Losartan and 10 µM PP2 (Losartan 26.4 ± 3.8% n=5 and PP2 19.7 ± 3.9% n=5). Our data suggests that Ang II can increase TRPV4 channel membrane expression in 4B cells through its action on AT1R involving a Src kinase pathway.

PMID: 25080500 [PubMed - as supplied by publisher]

Resting sympathetic baroreflex sensitivity in subjects with low and high tolerance to central hypovolemia induced by lower body negative pressure.

Fri, 08/01/2014 - 4:05am

Resting sympathetic baroreflex sensitivity in subjects with low and high tolerance to central hypovolemia induced by lower body negative pressure.

Front Physiol. 2014;5:241

Authors: Hinojosa-Laborde C, Ryan KL, Rickards CA, Convertino VA

Abstract
Central hypovolemia elicited by orthostasis or hemorrhage triggers sympathetically-mediated baroreflex responses to maintain organ perfusion; these reflexes are less sensitive in patients with orthostatic intolerance, and during conditions of severe blood loss, may result in cardiovascular collapse (decompensatory or circulatory shock). The ability to tolerate central hypovolemia is variable and physiological factors contributing to tolerance are emerging. We tested the hypothesis that resting muscle sympathetic nerve activity (MSNA) and sympathetic baroreflex sensitivity (BRS) are attenuated in male and female subjects who have low tolerance (LT) to central hypovolemia induced by lower body negative pressure (LBNP). MSNA and diastolic arterial pressure (DAP) were recorded in 47 human subjects who subsequently underwent LBNP to tolerance (onset of presyncopal symptoms). LT subjects experienced presyncopal symptoms prior to completing LBNP of -60 mm Hg, and subjects with high tolerance (HT) experienced presyncopal symptoms after completing LBNP of -60 mm Hg. Contrary to our hypothesis, resting MSNA burst incidence was not different between LT and HT subjects, and was not related to time to presyncope. BRS was assessed as the slope of the relationship between spontaneous fluctuations in DAP and MSNA during 5 min of supine rest. MSNA burst incidence/DAP correlations were greater than or equal to 0.5 in 37 subjects (LT: n = 9; HT: n = 28), and BRS was not different between LT and HT (-1.8 ± 0.3 vs. -2.2 ± 0.2 bursts·(100 beats)(-1) ·mm Hg(-1), p = 0.29). We conclude that tolerance to central hypovolemia is not related to either resting MSNA or sympathetic BRS.

PMID: 25071587 [PubMed]

Lymphatic pump treatment repeatedly enhances the lymphatic and immune systems.

Fri, 08/01/2014 - 4:05am
Related Articles

Lymphatic pump treatment repeatedly enhances the lymphatic and immune systems.

Lymphat Res Biol. 2013 Dec;11(4):219-26

Authors: Schander A, Padro D, King HH, Downey HF, Hodge LM

Abstract
BACKGROUND: Osteopathic practitioners utilize manual therapies called lymphatic pump techniques (LPT) to treat edema and infectious diseases. While previous studies examined the effect of a single LPT treatment on the lymphatic system, the effect of repeated applications of LPT on lymphatic output and immunity has not been investigated. Therefore, the purpose of this study was to measure the effects of repeated LPT on lymphatic flow, lymph leukocyte numbers, and inflammatory mediator concentrations in thoracic duct lymph (TDL).
METHODS AND RESULTS: The thoracic ducts of five mongrel dogs were cannulated, and lymph samples were collected during pre-LPT, 4 min of LPT, and 2 hours post-LPT. A second LPT (LPT-2) was applied after a 2 hour rest period. TDL flow was measured, and TDL were analyzed for the concentration of leukocytes and inflammatory mediators. Both LPT treatments significantly increased TDL flow, leukocyte count, total leukocyte flux, and the flux of interleukin-8 (IL-8), keratinocyte-derived chemoattractant (KC), nitrite (NO2(-)), and superoxide dismutase (SOD). The concentration of IL-6 increased in lymph over time in all experimental groups; therefore, it was not LPT dependent.
CONCLUSION: Clinically, it can be inferred that LPT at a rate of 1 pump per sec for a total of 4 min can be applied every 2 h, thus providing scientific rationale for the use of LPT to repeatedly enhance the lymphatic and immune system.

PMID: 24364845 [PubMed - indexed for MEDLINE]

Monitoring retinal morphologic and functional changes in mice following optic nerve crush.

Fri, 08/01/2014 - 4:05am
Related Articles

Monitoring retinal morphologic and functional changes in mice following optic nerve crush.

Invest Ophthalmol Vis Sci. 2014;55(6):3766-74

Authors: Liu Y, McDowell CM, Zhang Z, Tebow HE, Wordinger RJ, Clark AF

Abstract
PURPOSE: We characterized the morphologic and functional changes in optic nerve crushed mice and evaluated electroretinogram (ERG) responses as tools to monitor retinal ganglion cell (RGC) dysfunction.
METHODS: We performed optic nerve crush (ONC) unilaterally in adult BALB/cJ mice. The neuronal loss in the RGC layer (GCL) and superior colliculus (SC) was determined by Nissl staining. Retinal thickness was assessed by spectral-domain optical coherence tomography (SD-OCT) imaging. Retinal function was determined by pattern ERG and full-field flash ERG. Responses of pattern ERG, positive scotopic threshold response (pSTR), scotopic oscillatory potentials (OPs), and photopic negative response (PhNR) were analyzed.
RESULTS: The ONC induced progressive neuronal loss in GCL and contralateral SC starting from 7 and 28 days following ONC, respectively. A linear correlation was observed between combined thickness of nerve fiber layer (NFL), GCL, and inner plexiform layer (IPL) imaged by SD-OCT and cell numbers in GCL. Only half of the normal BALB/cJ mice exhibited pattern ERG response, which was smaller and later compared to C57BL/6J mice. The ONC reduced pattern ERG and pSTR, but the reduction of pattern ERG was earlier than pSTR, preceding the anatomical cell loss in the GCL. The PhNR and scotopic OPs were not affected by ONC.
CONCLUSIONS: The SD-OCT and ERG can be used to monitor noninvasively retinal morphologic and functional changes induced by ONC. Pattern ERG and pSTR are able to detect early RGC dysfunction, but pattern ERG exhibits higher sensitivity. Our results support the use of these tools in studies using the mouse ONC model.

PMID: 24854856 [PubMed - indexed for MEDLINE]

Involvement of AP-1 and C/EBPβ in upregulation of endothelin B (ETB) receptor expression in a rodent model of glaucoma.

Wed, 07/30/2014 - 4:05am
Related Articles

Involvement of AP-1 and C/EBPβ in upregulation of endothelin B (ETB) receptor expression in a rodent model of glaucoma.

PLoS One. 2013;8(11):e79183

Authors: He S, Minton AZ, Ma HY, Stankowska DL, Sun X, Krishnamoorthy RR

Abstract
Previous studies showed that the endothelin B receptor (ETB) expression was upregulated and played a key role in neurodegeneration in rodent models of glaucoma. However, the mechanisms underlying upregulation of ETB receptor expression remain largely unknown. Using promoter-reporter assays, the 1258 bp upstream the human ETB promoter region was found to be essential for constitutive expression of ETB receptor gene in human non-pigmented ciliary epithelial cells (HNPE). The -300 to -1 bp and -1258 to -600 bp upstream promoter regions of the ETB receptor appeared to be the key binding regions for transcription factors. In addition, the crucial AP-1 binding site located at -615 to -624 bp upstream promoter was confirmed by luciferase assays and CHIP assays which were performed following overexpression of c-Jun in HNPE cells. Overexpression of either c-Jun or C/EBPβ enhanced the ETB receptor promoter activity, which was reflected in increased mRNA and protein levels of ETB receptor. Furthermore, knock-down of either c-Jun or C/EBPβ in HNPE cells was significantly correlated to decreased mRNA levels of both ETB and ETA receptor. These observations suggest that c-Jun and C/EBPβ are important for regulated expression of the ETB receptor in HNPE cells. In separate experiments, intraocular pressure (IOP) was elevated in one eye of Brown Norway rats while the corresponding contralateral eye served as control. Two weeks of IOP elevation produced increased expression of c-Jun and C/EBPβ in the retinal ganglion cell (RGC) layer from IOP-elevated eyes. The mRNA levels of c-Jun, ETA and ETB receptor were upregulated by 2.2-, 3.1- and 4.4-fold in RGC layers obtained by laser capture microdissection from retinas of eyes with elevated IOP, compared to those from contralateral eyes. Taken together, these data suggest that transcription factor AP-1 plays a key role in elevation of ETB receptor in a rodent model of ocular hypertension.

PMID: 24265756 [PubMed - indexed for MEDLINE]

Bilorrhea Secondary to Bronchobiliary Fistula.

Sat, 07/26/2014 - 4:06am

Bilorrhea Secondary to Bronchobiliary Fistula.

Int Surg. 2014 July-August;99(4):438-441

Authors: Olivencia-Yurvati AH, Rollins C

Abstract
Abstract Bronchobiliary fistula (BBF) is a rare condition which occurs most commonly as a complication of hydatid cyst liver disease. The following report describes a patient who presented with biliptysis 6 months following decortication of an empyema that had occurred following partial hepatectomy of a colon cancer metastasis. This is the only case to our knowledge that describes the presentation of a BBF in this context. The patient was diagnosed with BBF and successfully underwent open thoracotomy for fistulectomy and repair.

PMID: 25058780 [PubMed - as supplied by publisher]

Two-week Normobaric Intermittent-Hypoxia Exposures Enhance Oxyhemoglobin Equilibrium and Cardiac Responses during Hypoxemia.

Sat, 07/26/2014 - 4:06am

Two-week Normobaric Intermittent-Hypoxia Exposures Enhance Oxyhemoglobin Equilibrium and Cardiac Responses during Hypoxemia.

Am J Physiol Regul Integr Comp Physiol. 2014 Jul 23;

Authors: Zhang P, Downey HF, Chen S, Shi X

Abstract
Intermittent-hypoxia (IH) is extensively applied to challenge cardiovascular and respiratory function, and to induce physiological acclimatization. The purpose of this study was to test the hypothesis that oxyhemoglobin equilibrium and tachycardiac responses during hypoxemia were enhanced after 14-day IH exposures. Normobaric-poikilocapnic hypoxia was induced with inhalation of 10% O2 for 5-6 min interspersed with 4-min recovery on eight non-smokers. Heart rate (HR), arterial O2 saturation (SaO2) and end-tidal O2 (PETO2) were continuously monitored during cyclic normoxia and hypoxia. These variables were compared during the 1st and 5th hypoxic bouts between Day 1 and Day 14. There was a rightward shift in the oxyhemoglobin equilibrium response following 14-day IH exposures, as indicated by the greater PETO2 (an index of arterial PO2) at 50% of SaO2 (P50) on Day 14 compared to Day 1: 33.9±1.5 vs 28.2±1.3 mmHg (P =0.005) during the 1st hypoxic bout and 39.4±2.4 vs 31.4±1.5 mmHg (P =0.006) during the 5th hypoxic bout; and by the augmented gains of ∆SaO2/∆PETO2 (i.e., de-oxygenation) during PETO2 from 65 to 40 mmHg in the 1st (1.12±0.08 vs 0.80±0.02 %/mmHg, P =0.001) and the 5th (1.76±0.31 vs 1.05±0.06 %/mmHg, P =0.024) hypoxic bouts. Repetitive IH exposures attenuated (P =0.049) the tachycardiac response to hypoxia while significantly enhanced normoxic R-R interval variability in low-frequency and high-frequency spectra without changes in arterial blood pressure at rest or during hypoxia. We conclude that 14-day IH exposures enhance arterial O2 delivery and improve vagal control of HR during hypoxic hypoxemia.

PMID: 25056104 [PubMed - as supplied by publisher]

Modulation of the rate of retinal degeneration in T17M RHO mice by reprogramming the unfolded protein response.

Sat, 07/26/2014 - 4:06am
Related Articles

Modulation of the rate of retinal degeneration in T17M RHO mice by reprogramming the unfolded protein response.

Adv Exp Med Biol. 2014;801:455-62

Authors: Choudhury S, Nashine S, Bhootada Y, Kunte MM, Gorbatyuk O, Lewin AS, Gorbatyuk M

Abstract
The goal of this study is to validate whether reprogramming of the UPR via modulation of pro-apoptotic caspase-7 and CHOP proteins could be an effective approach to slow down the rate of retinal degeneration in ADRP mice. In order to pursue our goal we created the T17M RHO CASP7 and T17M RHO CHOP mice to study the impact of the CASP7 or CHOP ablations in T17M RHO retina by ERG, SD-OCT, histology and western blot analysis. The scotopic ERG demonstrated that the ablation of the CASP7 in T17M RHO retina leads to significant preservation of the function of photoreceptors compared to control. Surprisingly, the ablation of pro-apoptotic CHOP protein in T17M RHO mice led to a more severe form of retinal degeneration. Results of the SD-OCT and histology were in agreement with the ERG data. The further analysis demonstrated that the preservation of the structure and function or the acceleration of the onset of the T17M RHO photoreceptor degeneration occurred via reprogramming of the UPR. In addition, the CASP7 ablation leads to the inhibition of cJUN mediated apoptosis, while the ablation of CHOP induces an increase in the HDAC. Thus, manipulation with the UPR requires careful examination in order to achieve a therapeutic effect.

PMID: 24664731 [PubMed - indexed for MEDLINE]

Reduction of stutter ratios in short tandem repeat loci typing of low copy number DNA samples.

Fri, 07/25/2014 - 4:05am
Related Articles

Reduction of stutter ratios in short tandem repeat loci typing of low copy number DNA samples.

Forensic Sci Int Genet. 2014 Jan;8(1):213-8

Authors: Seo SB, Ge J, King JL, Budowle B

Abstract
Increased height of stutter peaks is a phenomenon with low copy number (LCN) short tandem repeat (STR) typing that can impact interpretation. An alternative strategy of lowering the annealing/extension temperature (LT) at 56 °C was designed to attempt to decrease the heights of stutter peaks. STR typing results were generated in terms of stutter ratios using LT-PCR conditions and compared with data obtained using standard (STD) PCR conditions. DNA samples ranging from 100 to 25 pg were amplified using reagents contained in the AmpFℓSTR Identifiler PCR Amplification or AmpFℓSTR Identifiler Plus PCR Amplification kits with 32 or 34 PCR cycles. Stutter ratios decreased by an average of 14.7%, 14.9% and 18.1% at 100, 50 and 25 pg of template DNA under LT conditions compared with those of STD conditions in the Identifiler Kit amplified samples. The LT conditions also decreased average stutter ratios by 13.3% compared with those of STD conditions in the Identifiler Plus Kit amplified samples. The overall PCR efficiency obtained with STD and LT conditions with the two STR kits was comparable in terms of the number of detected alleles, peak heights and peak height ratios. These results support the hypothesis that a lower temperature annealing/extension step reduces the likelihood of slippage during PCR by enhancing the stability of the DNA polymerase/template DNA complex or the stability of the generated duplex than the conditions of the standard extension step. This stability in turn would result in lower stutter ratios.

PMID: 24315611 [PubMed - indexed for MEDLINE]

Low serum zinc is associated with elevated risk of cadmium nephrotoxicity.

Thu, 07/24/2014 - 4:04am

Low serum zinc is associated with elevated risk of cadmium nephrotoxicity.

Environ Res. 2014 Jul 17;134C:33-38

Authors: Lin YS, Ho WC, Caffrey JL, Sonawane B

Abstract
BACKGROUND: Despite animal evidence suggests that zinc modulates cadmium nephrotoxicity, limited human data are available.
OBJECTIVE: To test the hypothesis that low serum zinc concentrations may increase the risk of cadmium-mediated renal dysfunction in humans.
METHODS: Data from 1545 subjects aged 20 or older in the National Health and Nutrition Examination Survey (NHANES), 2011-2012 were analyzed. Renal function was defined as impaired when estimated glomerular filtration rate (eGFR) fell below 60ml/min/1.73m(2) and/or the urinary albumin-to-creatinine ratio surpassed 2.5 in men and 3.5mg/mmol in women.
RESULTS: Within the study cohort, 117 subjects had reduced eGFR and 214 had elevated urinary albumin. After adjusting for potential confounders, subjects with elevated blood cadmium (>0.53μg/L) were more likely to have a reduced eGFR (odds ratio [OR]=2.21, 95% confidence interval [CI]: 1.09-4.50) and a higher urinary albumin (OR=2.04, 95% CI: 1.13-3.69) than their low cadmium (<0.18μg/L) peers. In addition, for any given cadmium exposure, low serum zinc is associated with elevated risk of reduced eGFR (OR=3.38, 95% CI: 1.39-8.28). A similar increase in the odds ratio was observed between declining serum zinc and albuminuria but failed to reach statistical significance. Those with lower serum zinc/blood cadmium ratios were likewise at a greater risk of renal dysfunction (p<0.01).
CONCLUSIONS: This study results suggest that low serum zinc concentrations are associated with an increased risk of cadmium nephrotoxicity. Elevated cadmium exposure is global public health issue and the assessment of zinc nutritional status may be an important covariate in determining its effective renal toxicity.

PMID: 25042034 [PubMed - as supplied by publisher]

Characterization of [(3) H]LS-3-134, a Novel Arylamide Phenylpiperazine D3 Dopamine Receptor Selective Radioligand.

Thu, 07/24/2014 - 4:04am

Characterization of [(3) H]LS-3-134, a Novel Arylamide Phenylpiperazine D3 Dopamine Receptor Selective Radioligand.

J Neurochem. 2014 Jul 18;

Authors: Rangel-Barajas C, Malik M, Taylor M, Neve KA, Mach RH, Luedtke RR

Abstract
LS-3-134 is a substituted N-phenylpiperazine derivative that has been reported to exhibit a) high-affinity binding (Ki value 0.2 nM) at human D3 dopamine receptors, b) >100-fold D3 vs. D2 dopamine receptor subtype binding selectivity and c) low-affinity binding (Ki values >5,000 nM) at sigma 1 and sigma 2 receptors. Based upon a forskolin-dependent activation of the adenylyl cyclase inhibition assay, LS-3-134 is a weak partial agonist at both D2 and D3 dopamine receptor subtypes (29% and 35% of full agonist activity, respectively). In this study, [(3) H]-labeled LS-3-134 was prepared and evaluated to further characterize its use as a D3 dopamine receptor selective radioligand. Kinetic and equilibrium radioligand binding studies were performed. This radioligand rapidly reaches equilibrium (10-15 min at 37°C) and binds with high affinity to both human (Kd = 0.06 ± 0.01 nM) and rat (Kd = 0.2 ± 0.02 nM) D3 receptors expressed in HEK-293 cells. Direct and competitive radioligand binding studies using rat caudate and nucleus accumbens tissue indicate that [(3) H]LS-3-134 selectively binds a homogeneous population of binding sites with a dopamine D3 receptor pharmacological profile. Based upon these studies we propose that [(3) H]LS-3-134 represents a novel D3 dopamine receptor selective radioligand that can be used for studying the expression and regulation of the D3 dopamine receptor subtype. This article is protected by copyright. All rights reserved.

PMID: 25041389 [PubMed - as supplied by publisher]

Lenticular mitoprotection. Part B: GSK-3β and regulation of mitochondrial permeability transition for lens epithelial cells in atmospheric oxygen.

Thu, 07/24/2014 - 4:04am
Related Articles

Lenticular mitoprotection. Part B: GSK-3β and regulation of mitochondrial permeability transition for lens epithelial cells in atmospheric oxygen.

Mol Vis. 2013;19:2451-67

Authors: Brooks MM, Neelam S, Cammarata PR

Abstract
PURPOSE: Loss of integrity of either the inner or outer mitochondrial membrane results in the dissipation of the mitochondrial electrochemical gradient that leads to mitochondrial membrane permeability transition (mMPT). This study emphasizes the role of glycogen synthase kinase 3beta (GSK-3β) in maintaining mitochondrial membrane potential, thus preventing mitochondrial depolarization (hereafter termed mitoprotection). Using 3-(2,4-dichlorophenyl)-4-(1-methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione (SB216763), an inhibitor of GSK-3β, and drawing a distinction between it and 1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio] butadiene (UO126), an inhibitor of extracellular-signal-regulated kinase (ERK) phosphorylation, the means by which GSK-3β influences mitoprotection in cultured human lens epithelial (HLE-B3) cells and normal, secondary cultures of bovine lens epithelial cells, maintained in atmospheric oxygen, was investigated.
METHODS: Virally transfected human lens epithelial cells (HLE-B3) and normal cultures of bovine lens epithelial cells were exposed to acute hypoxic conditions (about 1% O2) followed by exposure to atmospheric oxygen (about 21% O2). Specific antisera and western blot analysis was used to examine the state of phosphorylation of ERK and GSK-3β, as well as the phosphorylation of a downstream substrate of GSK-3β, glycogen synthase (GS, useful in monitoring GSK-3β activity). The potentiometric dye, 1H-benzimidazolium-5,6-dichloro-2-[3-(5,6-dichloro-1,3-diethyl-1,3-dihydro-2H-benzimidazol-2-ylidene)-1-propenyl]-1,3-diethyl-iodide (JC-1), was used to monitor mitochondrial depolarization upon exposure of inhibitor treatment relative to the control cells (mock inhibition) in atmospheric oxygen. Caspase-3 activation was scrutinized to determine whether mitochondrial depolarization inevitably leads to apoptosis.
RESULTS: Treatment of HLE-B3 cells with SB216763 (12 µM) inactivated GSK-3β activity as verified by the enzyme's inability to phosphorylate its substrate, GS. SB216763-treated cells were not depolarized relative to the control cells as demonstrated with JC-1 fluorescent dye analysis. The HLE-B3 cells treated with UO126, which similarly blocked phosphorylation of GS, were nevertheless prone to mMPT relative to the control cells. Western blot analysis determined that Bcl-2-associated X (BAX) levels were unchanged for SB216763-treated or UO126-treated HLE-B3 cells when compared to their respective control cells. However, unlike the SB216763-treated cells, the UO126-treated cells showed a marked absence of Bcl-2, as well as phosphorylated Bcl-2 relative to the controls. UO126 treatment of bovine lens epithelial cells showed similar results with pBcl-2 levels, while the Bcl-2 content appeared unchanged relative to the control cells. HLE-B3 and normal bovine lens cell cultures showed susceptibility to mMPT associated with the loss of pBcl-2 by UO126 treatment.
CONCLUSIONS: MITOCHONDRIAL DEPOLARIZATION MAY OCCUR BY ONE OF TWO KEY OCCURRENCES: interruption of the electrochemical gradient across the inner mitochondrial membrane resulting in mMPT or by disruption of the integrity of the inner or outer mitochondrial membrane. The latter scenario is generally tightly regulated by members of the Bcl-2 family of proteins. Inhibition of GSK-3β activity by SB216763 blocks mMPT by preventing the opening of the mitochondrial permeability transition pore. UO126, likewise, inhibits GSK-3β activity, but unlike SB216763, inhibition of ERK phosphorylation induces the loss of intracellular pBcl-2 levels under conditions where intracellular BAX levels remain constant. These results suggest that the lenticular mitoprotection normally afforded by the inactivation of GSK-3β activity may, however, be bypassed by a loss of pBcl-2, an anti-apoptotic member of the Bcl-2 family. Bcl-2 prevents the translocation of BAX to the mitochondrial outer membrane inhibiting depolarization by disrupting the normal electrochemical gradient leading to mMPT.

PMID: 24319338 [PubMed - indexed for MEDLINE]

Single nucleotide polymorphism typing with massively parallel sequencing for human identification.

Thu, 07/24/2014 - 4:04am
Related Articles

Single nucleotide polymorphism typing with massively parallel sequencing for human identification.

Int J Legal Med. 2013 Nov;127(6):1079-86

Authors: Seo SB, King JL, Warshauer DH, Davis CP, Ge J, Budowle B

Abstract
The Ion AmpliSeq™ HID single nucleotide polymorphism (SNP) panel, a primer pool of 103 autosomal SNPs and 33 Y-SNPs, was evaluated using the Ion 314™ Chip on the Ion PGM™ Sequencer with four DNA samples. The study focused on the sequencing of DNA at three different initial target quantities, related interpretation issues, and concordance of results with another sequencing platform, i.e., Genome Analyzer IIx. With 10 ng of template DNA, all genotypes at the 136 SNPs were detected. With 1 ng of DNA, all SNPs were detected and one SNP locus in one sample showed extreme heterozygote imbalance on allele coverage. With 100 pg of DNA, an average of 1.6 SNP loci were not detected, and an average of 4.3 SNPs showed heterozygote imbalance. The average sequence coverage was 945-600× at autosomal SNPs and 465-209× at Y-SNPs for 10 ng-100 pg of DNA. The average heterozygote allele coverage ratio was 89.6-61.8 % for 10 ng-100 pg of DNA. At 10 ng of DNA, all genotypes of the 95 SNPs shared between the two different sequencing platforms were concordant except for one SNP, rs1029047. The error was due to the misalignment of a flanking homopolymer. Overall, the data support that genotyping a large battery of SNPs is feasible with massively parallel sequencing. With barcode systems, better allele balance, and specifically designed alignment software, a more comprehensive rapid genotyping and more cost-effective results may be obtained from multiple samples in one analysis than are possible with current typing and capillary electrophoresis systems.

PMID: 23736940 [PubMed - indexed for MEDLINE]

5-hydroxytryptamine-mediated neurotransmission modulates spontaneous and vagal-evoked glutamate release in the nucleus of the solitary tract effect of uptake blockade.

Tue, 07/22/2014 - 4:04am
Related Articles

5-hydroxytryptamine-mediated neurotransmission modulates spontaneous and vagal-evoked glutamate release in the nucleus of the solitary tract effect of uptake blockade.

J Pharmacol Exp Ther. 2014 May;349(2):288-96

Authors: Hosford PS, Mifflin SW, Ramage AG

Abstract
The effect of blockade of either 5-hydroxytryptamine (5-HT)/serotonin transporter (SERT) with citalopram or the organic cation transporter 3 (OCT3)/plasma membrane monoamine transporter (PMAT) with decynium-22 (D-22) on spontaneous and evoked release of 5-HT in the nucleus tractus solitarius (NTS) was investigated in rat brainstem slices treated with gabazine. 5-HT release was measured indirectly by changes in the frequency and amplitude of glutamatergic miniature excitatory postsynaptic currents (mEPSCs) [in the presence of tetrodotoxin (TTX)] and evoked EPSCs. Blockade of 5-HT3 receptors with granisetron reduced, whereas the 5-HT3 agonist phenylbiguanide increased, the frequency of mEPSCs. 5-HT decreased mEPSC frequency at low concentrations and increased frequency at high concentrations. This inhibition was blocked by the 5-HT1A antagonist N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide (WAY-100635), which was ineffective on its own, whereas the excitation was reversed by granisetron. The addition of citalopram or D-22 caused inhibition, which was prevented by 5-HT1A blockade. Thus, in the NTS, the spontaneous release of 5-HT is able to activate 5-HT3 receptors, but not 5-HT1A receptors, as the release in their vicinity is removed by uptake. The ineffectiveness of corticosterone suggests that the low-affinity, high-capacity transporter is PMAT, not OCT3. For evoked 5-HT release, only D-22 caused an increase in the amplitude of EPSCs, with a decrease in the paired pulse ratio, and increased the number of spontaneous EPSCs after 20-Hz stimulation. Thus, for the evoked release of 5-HT, the low-affinity, high-capacity transporter PMAT, but not 5-HT transporter (5-HTT)/SERT, is important in the regulation of changes in 5-HT extracellular concentration.

PMID: 24618127 [PubMed - indexed for MEDLINE]