Recent Research Articles from UNTHSC

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Native American population data based on the Globalfiler(®) autosomal STR loci.

Sun, 07/17/2016 - 06:38

Native American population data based on the Globalfiler(®) autosomal STR loci.

Forensic Sci Int Genet. 2016 Jun 27;

Authors: Ng J, Oldt RF, McCulloh KL, Weise JA, Viray J, Budowle B, Smith DG, Kanthaswamy S

Abstract
Native American population data are limited and thus impact computing accurate statistical parameters for forensic investigations. Thus, additional information should be generated from geographically representative tribes in North America, particularly from those that are not included in existing population databases for forensic use. The Globafiler(®) PCR Amplification kit was used to produce STR genotypic data for 533 individuals who represent 31 Native American tribal populations derived from eight geographically diverse regions in North America. Population genetic estimates from 21 autosomal STRs are reported.

PMID: 27421760 [PubMed - as supplied by publisher]

Authors' Response.

Wed, 07/13/2016 - 06:30

Authors' Response.

J Forensic Sci. 2015 Nov;60(6):1669-1670

Authors: Moretti TR, Budowle B, Buckleton JS

PMID: 27404296 [PubMed - as supplied by publisher]

HDAC Inhibitor-Mediated Epigenetic Regulation of Glaucoma-Associated TGFβ2 in the Trabecular Meshwork.

Wed, 07/13/2016 - 06:30

HDAC Inhibitor-Mediated Epigenetic Regulation of Glaucoma-Associated TGFβ2 in the Trabecular Meshwork.

Invest Ophthalmol Vis Sci. 2016 Jul 1;57(8):3698-3707

Authors: Bermudez JY, Webber HC, Patel GC, Liu X, Cheng YQ, Clark AF, Mao W

Abstract
Purpose: Elevated intraocular pressure (IOP) in primary open-angle glaucoma (POAG) results from glaucomatous damage to the trabecular meshwork (TM). The glaucoma-associated factor TGFβ2 is increased in aqueous humor and TM of POAG patients. We hypothesize that histone acetylation has a role in dysregulated TGFβ2 expression.
Methods: Protein acetylation was compared between nonglaucomatous TM (NTM) and glaucomatous TM (GTM) cells using Western immunoblotting (WB). Nonglaucomatous TM cells were treated with 10 nM thailandepsin-A (TDP-A), a potent histone deacetylase inhibitor for 4 days. Total and nuclear proteins, RNA, and nuclear protein-DNA complexes were harvested for WB, quantitative PCR (qPCR), and chromatin immunoprecipitation (ChIP) assays, respectively. Paired bovine eyes were perfused with TDP-A versus DMSO, or TDP-A versus TDP-A plus the TGFβ pathway inhibitor LY364947 for 5 to 9 days. Intraocular pressure, TM, and perfusate proteins were compared.
Results: We found increased acetylated histone 3 and total protein acetylation in the GTM cells and TDP-A treated NTM cells. Chromatin immunoprecipitation assays showed that TDP-A induced histone hyperacetylation associated with the TGFβ2 promoter. This change of acetylation significantly increased TGFβ2 mRNA and protein expression in NTM cells. In perfusion-cultured bovine eyes, TDP-A increased TGFβ2 in the perfusate as well as elevated IOP. Histologic and immunofluorescent analyses showed increased extracellular matrix and cytoskeletal proteins in the TM of TDP-A treated bovine eyes. Cotreatment with the TGFβ pathway inhibitor LY364947 blocked TDP-A-induced ocular hypertension.
Conclusions: Our results suggest that histone acetylation has an important role in increased expression of the glaucoma-associated factor TGFβ2. Histone hyperacetylation may be the initiator of glaucomatous damage to the TM.

PMID: 27403998 [PubMed - as supplied by publisher]

Biomarkers in Sporadic and Familial Alzheimer's Disease.

Wed, 07/13/2016 - 06:30
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Biomarkers in Sporadic and Familial Alzheimer's Disease.

J Alzheimers Dis. 2015;47(2):291-317

Authors: Lista S, O'Bryant SE, Blennow K, Dubois B, Hugon J, Zetterberg H, Hampel H

Abstract
Most forms of Alzheimer's disease (AD) are sporadic (sAD) or inherited in a non-Mendelian fashion, and less than 1% of cases are autosomal-dominant. Forms of sAD do not exhibit familial aggregation and are characterized by complex genetic and environmental interactions. Recently, the expansion of genomic methodologies, in association with substantially larger combined cohorts, has resulted in various genome-wide association studies that have identified several novel genetic associations of AD. Currently, the most effective methods for establishing the diagnosis of AD are defined by multi-modal pathways, starting with clinical and neuropsychological assessment, cerebrospinal fluid (CSF) analysis, and brain-imaging procedures, all of which have significant cost- and access-to-care barriers. Consequently, research efforts have focused on the development and validation of non-invasive and generalizable blood-based biomarkers. Among the modalities conceptualized by the systems biology paradigm and utilized in the "exploratory biomarker discovery arena", proteome analysis has received the most attention. However, metabolomics, lipidomics, transcriptomics, and epigenomics have recently become key modalities in the search for AD biomarkers. Interestingly, biomarker changes for familial AD (fAD), in many but not all cases, seem similar to those for sAD. The integration of neurogenetics with systems biology/physiology-based strategies and high-throughput technologies for molecular profiling is expected to help identify the causes, mechanisms, and biomarkers associated with the various forms of AD. Moreover, in order to hypothesize the dynamic trajectories of biomarkers through disease stages and elucidate the mechanisms of biomarker alterations, updated and more sophisticated theoretical models have been proposed for both sAD and fAD.

PMID: 26401553 [PubMed - indexed for MEDLINE]

Investigation of the Dermal Absorption and Irritation Potential of Sertaconazole Nitrate Anhydrous Gel.

Tue, 07/12/2016 - 06:41

Investigation of the Dermal Absorption and Irritation Potential of Sertaconazole Nitrate Anhydrous Gel.

Pharmaceutics. 2016;8(3)

Authors: Manian M, Madrasi K, Chaturvedula A, Banga AK

Abstract
Effective topical therapy of cutaneous fungal diseases requires the delivery of the active agent to the target site in adequate concentrations to produce a pharmacological effect and inhibit the growth of the pathogen. In addition, it is important to determine the concentration of the drug in the skin in order to evaluate the subsequent efficacy and potential toxicity for topical formulations. For this purpose, an anhydrous gel containing sertaconazole nitrate as a model drug was formulated and the amount of the drug in the skin was determined by in vitro tape stripping. The apparent diffusivity and partition coefficients were then calculated by a mathematical model describing the dermal absorption as passive diffusion through a pseudo-homogenous membrane. The skin irritation potential of the formulation was also assessed by using the in vitro Epiderm™ model. An estimation of the dermal absorption parameters allowed us to evaluate drug transport across the stratum corneum following topical application. The estimated concentration for the formulation was found to be higher than the MIC100 at the target site which suggested its potential efficacy for treating fungal infections. The skin irritation test showed the formulation to be non-irritating in nature. Thus, in vitro techniques can be used for laying the groundwork in developing efficient and non-toxic topical products.

PMID: 27399763 [PubMed - as supplied by publisher]

The Effect of the Sigma-1 Receptor Selective Compound LS-1-137 on the DOI-Induced Head Twitch Response in Mice.

Tue, 07/12/2016 - 06:41

The Effect of the Sigma-1 Receptor Selective Compound LS-1-137 on the DOI-Induced Head Twitch Response in Mice.

Pharmacol Biochem Behav. 2016 Jul 7;

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

Abstract
Several receptor mediated pathways have been shown to modulate the murine head twitch response (HTR). However, the role of sigma receptors in the murine (±)-2,5-dimethoxy-4-iodoamphetamine (DOI)-induced HTR has not been previously investigated. We examined the ability of LS-1-137, a novel sigma-1 vs. sigma-2 receptor selective phenylacetamide, to modulate the DOI-induced HTR in DBA/2J mice. We also assessed the in vivo efficacy of reference sigma-1 receptor antagonists and agonists PRE-084 and PPCC. The effect of the sigma-2 receptor selective antagonist RHM-1-86 was also examined. Rotarod analysis was performed to monitor motor coordination after LS-1-137 administration. Radioligand binding techniques were used to determine the affinity of LS-1-137 at 5-HT2A and 5-HT2C receptors. LS-1-137 and the sigma-1 receptor antagonists haloperidol and BD 1047 were able to attenuate a DOI-induced HTR, indicating that LS-1-137 was acting in vivo as a sigma-1 receptor antagonist. LS-1-137 did not compromise rotarod performance within a dose range capable of attenuating the effects of DOI. Radioligand binding studies indicate that LS-1-137 exhibits low affinity binding at both 5-HT2A and 5-HT2C receptors. Based upon the results from these and our previous studies, LS-1-137 is a neuroprotective agent that attenuates the murine DOI-induced HTR independent of activity at 5-HT2 receptor subtypes, D2-like dopamine receptors, sigma-2 receptors and NMDA receptors. LS-1-137 appears to act as a sigma-1 receptor antagonist to inhibit the DOI-induced HTR. Therefore, the DOI-induced HTR can be used to assess the in vivo efficacy of sigma-1 receptor selective compounds.

PMID: 27397487 [PubMed - as supplied by publisher]

Evolving Evidence for the Value of Neuroimaging Methods and Biological Markers in Subjects Categorized with Subjective Cognitive Decline.

Tue, 07/12/2016 - 06:41
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Evolving Evidence for the Value of Neuroimaging Methods and Biological Markers in Subjects Categorized with Subjective Cognitive Decline.

J Alzheimers Dis. 2015 Sep 24;48 Suppl 1:S171-91

Authors: Lista S, Molinuevo JL, Cavedo E, Rami L, Amouyel P, Teipel SJ, Garaci F, Toschi N, Habert MO, Blennow K, Zetterberg H, O'Bryant SE, Johnson L, Galluzzi S, Bokde AL, Broich K, Herholz K, Bakardjian H, Dubois B, Jessen F, Carrillo MC, Aisen PS, Hampel H

Abstract
There is evolving evidence that individuals categorized with subjective cognitive decline (SCD) are potentially at higher risk for developing objective and progressive cognitive impairment compared to cognitively healthy individuals without apparent subjective complaints. Interestingly, SCD, during advancing preclinical Alzheimer's disease (AD), may denote very early, subtle cognitive decline that cannot be identified using established standardized tests of cognitive performance. The substantial heterogeneity of existing SCD-related research data has led the Subjective Cognitive Decline Initiative (SCD-I) to accomplish an international consensus on the definition of a conceptual research framework on SCD in preclinical AD. In the area of biological markers, the cerebrospinal fluid signature of AD has been reported to be more prevalent in subjects with SCD compared to healthy controls; moreover, there is a pronounced atrophy, as demonstrated by magnetic resonance imaging, and an increased hypometabolism, as revealed by positron emission tomography, in characteristic brain regions affected by AD. In addition, SCD individuals carrying an apolipoprotein ɛ4 allele are more likely to display AD-phenotypic alterations. The urgent requirement to detect and diagnose AD as early as possible has led to the critical examination of the diagnostic power of biological markers, neurophysiology, and neuroimaging methods for AD-related risk and clinical progression in individuals defined with SCD. Observational studies on the predictive value of SCD for developing AD may potentially be of practical value, and an evidence-based, validated, qualified, and fully operationalized concept may inform clinical diagnostic practice and guide earlier designs in future therapy trials.

PMID: 26402088 [PubMed - indexed for MEDLINE]

Primary Cutaneous Diffuse Large B-Cell Lymphoma With a MYC-IGH Rearrangement and Gain of BCL2: Expanding the Spectrum of MYC/BCL2 Double-Hit Lymphomas.

Sat, 07/09/2016 - 06:30

Primary Cutaneous Diffuse Large B-Cell Lymphoma With a MYC-IGH Rearrangement and Gain of BCL2: Expanding the Spectrum of MYC/BCL2 Double-Hit Lymphomas.

Am J Dermatopathol. 2016 Jul 7;

Authors: Testo N, Olson LC, Subramaniyam S, Hanson T, Magro CM

Abstract
Aggressive extracutaneous B-cell lymphomas span the various stages of B-cell ontogeny and include B-cell lymphoblastic lymphoma, Burkitt lymphoma, mantle cell lymphoma, and diffuse large B-cell lymphoma. Diffuse large B-cell lymphomas represent the most common histologic subtype of non-Hodgkin lymphomas, comprising 30% of adult non-Hodgkin lymphomas in the United States. A distinctive form of diffuse large B-cell lymphoma is the double-hit lymphoma, with most cases exhibiting a combined MYC and BCL2 rearrangement, leading some hematopathologists to propose the term MYC/BCL2 lymphoma. More recently, MYC rearrangement with multiple copies/gain of BCL2 or multiple copies/gain of MYC with a BCL2 rearrangement have been described and exhibit a very similar clinical course to conventional double-hit lymphomas. We report the seventh case of diffuse large B-cell lymphoma exhibiting this distinct cytogenetic abnormality and the first reported case in the skin. The patient's clinical course was aggressive, succumbing to disease 18 months after his initial presentation.

PMID: 27391453 [PubMed - as supplied by publisher]

No increased risk of hospitalization for heart failure for patients treated with dipeptidyl peptidase-4 inhibitors in Taiwan.

Sat, 07/09/2016 - 06:30

No increased risk of hospitalization for heart failure for patients treated with dipeptidyl peptidase-4 inhibitors in Taiwan.

Int J Cardiol. 2016 Jun 24;220:14-20

Authors: Chang CH, Chang YC, Lin JW, Caffrey JL, Wu LC, Lai MS, Chuang LM

Abstract
BACKGROUND: Saxagliptin has been reported to be associated with an increased risk of hospitalization for heart failure (HF). The objective of this study was to test whether the increased risk is drug specific or a class effect for dipeptidyl peptidase-4 (DPP-4) inhibitors.
METHODS: Diabetic patients prescribed sitagliptin, saxagliptin, and vildagliptin between 2011 and 2013 were identified from Taiwan's National Health Insurance (NHI) claims database. The outcome of interest was the first hospitalization for HF. The patients were followed for one year from drug initiation to outcome occurrence, death, or study termination (December 31, 2013). A Cox proportional hazards regression model was used to calculate the hazard ratios (HR) and their 95% confidence intervals, using sitagliptin as the reference group.
RESULTS: A total of 239,669 patients, including 159,330 sitagliptin, 38,561 saxagliptin, and 41,778 vildagliptin initiators, were included in the analysis. With a follow-up period ranging from 269days (vildagliptin) to 313days (sitagliptin), the crude incidence rate of HF was 2.77, 2.63, and 1.91 per 100 person-years for sitagliptin, saxagliptin, and vildagliptin, respectively. Saxagliptin had a similar risk (HR: 0.98, 95% CI: 0.91-1.06) to sitagliptin, while vildagliptin was associated with a lower risk of HF (HR: 0.85, 95% CI: 0.78-0.93). Auxiliary analyses using acarbose (n=130,800) as a reference group consistently showed no increased risk of HF associated with DDP-4 inhibitors.
CONCLUSION: Three DPP-4 inhibitors studied seem to be safe regarding the risk of HF, while the reduced risk of vildagliptin might be a spurious association or a chance finding.

PMID: 27389437 [PubMed - as supplied by publisher]

Glucocorticoid Therapy and ocular hypertension.

Sat, 07/09/2016 - 06:30

Glucocorticoid Therapy and ocular hypertension.

Eur J Pharmacol. 2016 Jul 4;

Authors: Dibas A, Yorio T

Abstract
The projected number of people who will develop age-related macular degeneration in estimated at 2020 is 196 million and is expected to reach 288 million in 2040. Also, the number of people with Diabetic retinopathy will grow from 126.6 million in 2010 to 191.0 million by 2030. In addition, it is estimated that there are 2.3 million people suffering from uveitis worldwide. Because of the anti-inflammatory properties of glucocorticoids (GCs), they are often used topically and/or intravitreally to treat ocular inflammation conditions or edema associated with macular degeneration and diabetic retinopathy. Unfortunately, ocular GC therapy can lead to severe side effects. Serious and sometimes irreversible eye damage can occur as a result of the development of GC-induced ocular hypertension causing secondary open-angle glaucoma. According to the world health organization, glaucoma is the second leading cause of blindness in the world and it is estimated that 80 million will suffer from glaucoma by 2020. In the current review, mechanisms of GC-induced damage in ocular tissue, GC-resistance, and enhancing GC therapy will be discussed.

PMID: 27388141 [PubMed - as supplied by publisher]

Cross-sectional and longitudinal risk of physical impairment in a cohort of postmenopausal women who experience physical and verbal abuse.

Sat, 07/09/2016 - 06:30
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Cross-sectional and longitudinal risk of physical impairment in a cohort of postmenopausal women who experience physical and verbal abuse.

BMC Womens Health. 2015;15:98

Authors: Cannell MB, Weitlauf JC, Garcia L, Andresen EM, Margolis KL, Manini TM

Abstract
BACKGROUND: Exposure to interpersonal violence, namely verbal and physical abuse, is a highly prevalent threat to women's health and well-being. Among older, post-menopausal women, several researchers have characterized a possible bi-directional relationship of abuse exposure and diminished physical functioning. However, studies that prospectively examine the relationship between interpersonal abuse exposure and physical functioning across multiple years of observation are lacking. To address this literature gap, we prospectively evaluate the association between abuse exposure and physical functioning in a large, national cohort of post-menopausal women across 12 years of follow-up observation.
METHODS: Multivariable logistic regression was used to measure the adjusted association between experiencing abuse and physical function score at baseline in 154,902 Women's Health Initiative (WHI) participants. Multilevel modeling, where the trajectories of decline in physical function were modeled as a function of time-varying abuse exposure, was used to evaluate the contribution of abuse to trajectories of physical function scores over time.
RESULT: Abuse was prevalent among WHI participants, with 11 % of our study population reporting baseline exposure. Verbal abuse was the most commonly reported abuse type (10 %), followed by combined physical and verbal abuse (1 %), followed by physical abuse in the absence of verbal abuse (0.2 %). Abuse exposure (all types) was associated with diminished physical functioning, with women exposed to combined physical and verbal abuse presenting baseline physical functioning scores consistent with non-abused women 20 years senior. Results did not reveal a differential rate of decline over time in physical functioning based on abuse exposure.
CONCLUSIONS: Taken together, our findings suggest a need for increased awareness of the prevalence of abuse exposure among postmenopausal women; they also underscore the importance of clinician's vigilance in their efforts toward the prevention, early detection and effective intervention with abuse exposure, including verbal abuse exposure, in post-menopausal women. Given our findings related to abuse exposure and women's diminished physical functioning at WHI baseline, our work illuminates a need for further study, particularly the investigation of this association in younger, pre-menopausal women so that the temporal ordering if this relationship may be better understood.

PMID: 26554450 [PubMed - indexed for MEDLINE]

Aquaporins: Their role in gastrointestinal malignancies.

Thu, 07/07/2016 - 06:33
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Aquaporins: Their role in gastrointestinal malignancies.

Cancer Lett. 2016 Apr 1;373(1):12-8

Authors: Nagaraju GP, Basha R, Rajitha B, Alese OB, Alam A, Pattnaik S, El-Rayes B

Abstract
Aquaporins (AQPs) are small (~30 kDa monomers) integral membrane water transport proteins that allow water to flow through cell membranes in reaction to osmotic gradients in cells. In mammals, the family of AQPs has thirteen (AQP0-12) unique members that mediate critical biological functions. Since AQPs can impact cell proliferation, migration and angiogenesis, their role in various human cancers is well established. Recently, AQPs have been explored as potential diagnostic and therapeutic targets in gastrointestinal (GI) cancers. GI cancers encompass multiple sites including the colon, esophagus, stomach and pancreas. Research in the last three decades has revealed biological aspects and signaling pathways critical for the development of GI cancers. Since the majority of these cancers are very aggressive and rapidly metastasizes, identifying effective targets is crucial for treatment. Preclinical studies have utilized inhibitors of specific AQPs and knock down of AQP expression using siRNA. Although several studies have explored the role of AQPs in colorectal, esophageal, gastric, hepatocellular and pancreatic cancers, there is no comprehensive review compiling the available information on GI cancers as has been published for other malignancies such as ovarian cancer. Due to the similarities and association of various sites of GI cancers, it is helpful to consider these results collectively in order to better understand the role of specific AQPs in critical GI cancers. This review summarizes the current knowledge of the role of AQPs in GI malignancies with particular focus on diagnosis and therapeutic applications.

PMID: 26780474 [PubMed - indexed for MEDLINE]

Cerebral small vessel disease and Alzheimer's disease.

Thu, 07/07/2016 - 06:33
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Cerebral small vessel disease and Alzheimer's disease.

Clin Interv Aging. 2015;10:1695-704

Authors: Cai Z, Wang C, He W, Tu H, Tang Z, Xiao M, Yan LJ

Abstract
Cerebral small vessel disease (CSVD) is a group of pathological processes with multifarious etiology and pathogenesis that are involved into the small arteries, arterioles, venules, and capillaries of the brain. CSVD mainly contains lacunar infarct or lacunar stroke, leukoaraiosis, Binswanger's disease, and cerebral microbleeds. CSVD is an important cerebral microvascular pathogenesis as it is the cause of 20% of strokes worldwide and the most common cause of cognitive impairment and dementia, including vascular dementia and Alzheimer's disease (AD). It has been well identified that CSVD contributes to the occurrence of AD. It seems that the treatment and prevention for cerebrovascular diseases with statins have such a role in the same function for AD. So far, there is no strong evidence-based medicine to support the idea, although increasing basic studies supported the fact that the treatment and prevention for cerebrovascular diseases will benefit AD. Furthermore, there is still lack of evidence in clinical application involved in specific drugs to benefit both AD and CSVD.

PMID: 26604717 [PubMed - indexed for MEDLINE]

Absolute humidity and the human nose: A reanalysis of climate zones and their influence on nasal form and function.

Tue, 07/05/2016 - 18:34

Absolute humidity and the human nose: A reanalysis of climate zones and their influence on nasal form and function.

Am J Phys Anthropol. 2016 Jul 4;

Authors: Maddux SD, Yokley TR, Svoma BM, Franciscus RG

Abstract
OBJECTIVES: Investigations into the selective role of climate on human nasal variation commonly divide climates into four broad adaptive zones (hot-dry, hot-wet, cold-dry, and cold-wet) based on temperature and relative humidity. Yet, absolute humidity-not relative humidity-is physiologically more important during respiration. Here, we investigate the global distribution of absolute humidity to better clarify ecogeographic demands on nasal physiology.
METHODS: We use monthly observations from the Climatic Research Unit Timeseries 3 (CRU TS3) database to construct global maps of average annual temperature, relative humidity and absolute humidity. Further, using data collected by Thomson and Buxton (1923) for over 15,000 globally-distributed individuals, we calculate the actual amount of heat and water that must be transferred to inspired air in different climatic regimes to maintain homeostasis, and investigate the influence of these factors on the nasal index.
RESULTS: Our results show that absolute humidity, like temperature, generally decreases with latitude. Furthermore, our results demonstrate that environments typically characterized as "cold-wet" actually exhibit low absolute humidities, with values virtually identical to cold-dry environments and significantly lower than hot-wet and even hot-dry environments. Our results also indicate that strong associations between the nasal index and absolute humidity are, potentially erroneously, predicated on individuals from hot-dry environments possessing intermediate (mesorrhine) nasal indices.
DISCUSSION: We suggest that differentially allocating populations to cold-dry or cold-wet climates is unlikely to reflect different selective pressures on respiratory physiology and nasal morphology-it is cold-dry, and to a lesser degree hot-dry environments, that stress respiratory function. Our study also supports assertions that demands for inspiratory modification are reduced in hot-wet environments, and that expiratory heat elimination for thermoregulation is a greater selective pressure in such environments.

PMID: 27374937 [PubMed - as supplied by publisher]

[Novel therapeutic targets for reduction of intraocular pressure in primary open angle glaucoma].

Tue, 07/05/2016 - 18:34

[Novel therapeutic targets for reduction of intraocular pressure in primary open angle glaucoma].

Zhonghua Yan Ke Za Zhi. 2016 Jun 11;52(6):471-475

Authors: Mao WM, Liu Y, Wordinger YH, Clark AF, Pang IH

Abstract
Glaucoma is a major cause of blindness in China and the world. Currently, all therapeutic means in treating open-angle glaucoma are limited to control the progression of optic neuropathy by lowering intraocular pressure (IOP). Clinically available medicines lower IOP by either enhancing the uveoscleral pathway or inhibiting aqueous humor production. Since the primary cause of IOP elevation in POAG is elevated outflow resistance in the trabecular outflow pathway, current medicines are not able to correct the underlying pathogenesis and pathophysiology of the disease. In this review article, we discuss a series of new therapeutic targets and therapeutic approaches that are designed to directly modify the pathological changes related to the reduction in trabecular outflow in glaucoma patients. Some of these targets and approaches may produce a significant breakthrough in the treatment of this devastating disease. (Chin J Ophthalmol, 2016, 52: 471-475).

PMID: 27373575 [PubMed - as supplied by publisher]

5-(N, N-Hexamethylene) amiloride is a GABA-A ρ1 receptor positive allosteric modulator.

Sat, 07/02/2016 - 06:32

5-(N, N-Hexamethylene) amiloride is a GABA-A ρ1 receptor positive allosteric modulator.

Channels (Austin). 2016 Jul 1;:0

Authors: Snell HD, Gonzales EB

Abstract
Guanidine compounds act as ion channel modulators. In the case of Cys-loop receptors, the guanidine compound amiloride antagonized the heteromeric GABA-A, glycine, and nicotinic acetylcholine receptors. However, amiloride exhibits characteristics consistent with a positive allosteric modulator for the human GABA-A (hGABA-A) ρ1 receptor. Site-directed mutagenesis revealed that the positive allosteric modulation was influenced by the GABA-A ρ1 second transmembrane domain 15' position, a site implicated in ligand allosteric modulation of Cys-loop receptors. There are a variety of amiloride derivatives that provide opportunities to assess the significance of amiloride functional groups (e.g., the guanidine group, the pyrazine ring, etc.) in the modulation of the GABA-A ρ1 receptor activity. We utilized three amiloride derivatives (benzamil, phenamil, and 5-(N, N-Hexamethylene) amiloride) to assess the contribution of these groups towards the potentiation of the GABA-A ρ1 receptor. Benzamil and phenamil failed to potentiate on the wild type GABA-A ρ1 GABA-mediated current while HMA demonstrated efficacy only at the highest concentration studied. The hGABA-A ρ1 (I15'N) mutant receptor activity was potentiated by lower HMA concentrations compared to the wild type receptor. Our findings suggest that an exposed guanidine group on amiloride and amiloride derivatives is critical for modulating the GABA-A ρ1 receptor. The present study provides a conceptual framework for predicting which amiloride derivatives will demonstrate positive allosteric modulation of the GABA-A ρ1 receptor.

PMID: 27367557 [PubMed - as supplied by publisher]

Cholinergic Neurons in the Basal Forebrain Promote Wakefulness by Actions on Neighboring Non-Cholinergic Neurons: An Opto-Dialysis Study.

Sat, 07/02/2016 - 06:32
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Cholinergic Neurons in the Basal Forebrain Promote Wakefulness by Actions on Neighboring Non-Cholinergic Neurons: An Opto-Dialysis Study.

J Neurosci. 2016 Feb 10;36(6):2057-67

Authors: Zant JC, Kim T, Prokai L, Szarka S, McNally J, McKenna JT, Shukla C, Yang C, Kalinchuk AV, McCarley RW, Brown RE, Basheer R

Abstract
UNLABELLED: Understanding the control of sleep-wake states by the basal forebrain (BF) poses a challenge due to the intermingled presence of cholinergic, GABAergic, and glutamatergic neurons. All three BF neuronal subtypes project to the cortex and are implicated in cortical arousal and sleep-wake control. Thus, nonspecific stimulation or inhibition studies do not reveal the roles of these different neuronal types. Recent studies using optogenetics have shown that "selective" stimulation of BF cholinergic neurons increases transitions between NREM sleep and wakefulness, implicating cholinergic projections to cortex in wake promotion. However, the interpretation of these optogenetic experiments is complicated by interactions that may occur within the BF. For instance, a recent in vitro study from our group found that cholinergic neurons strongly excite neighboring GABAergic neurons, including the subset of cortically projecting neurons, which contain the calcium-binding protein, parvalbumin (PV) (Yang et al., 2014). Thus, the wake-promoting effect of "selective" optogenetic stimulation of BF cholinergic neurons could be mediated by local excitation of GABA/PV or other non-cholinergic BF neurons. In this study, using a newly designed opto-dialysis probe to couple selective optical stimulation with simultaneous in vivo microdialysis, we demonstrated that optical stimulation of cholinergic neurons locally increased acetylcholine levels and increased wakefulness in mice. Surprisingly, the enhanced wakefulness caused by cholinergic stimulation was abolished by simultaneous reverse microdialysis of cholinergic receptor antagonists into BF. Thus, our data suggest that the wake-promoting effect of cholinergic stimulation requires local release of acetylcholine in the basal forebrain and activation of cortically projecting, non-cholinergic neurons, including the GABAergic/PV neurons.
SIGNIFICANCE STATEMENT: Optogenetics is a revolutionary tool to assess the roles of particular groups of neurons in behavioral functions, such as control of sleep and wakefulness. However, the interpretation of optogenetic experiments requires knowledge of the effects of stimulation on local neurotransmitter levels and effects on neighboring neurons. Here, using a novel "opto-dialysis" probe to couple optogenetics and in vivo microdialysis, we report that optical stimulation of basal forebrain (BF) cholinergic neurons in mice increases local acetylcholine levels and wakefulness. Reverse microdialysis of cholinergic antagonists within BF prevents the wake-promoting effect. This important result challenges the prevailing dictum that BF cholinergic projections to cortex directly control wakefulness and illustrates the utility of "opto-dialysis" for dissecting the complex brain circuitry underlying behavior.

PMID: 26865627 [PubMed - indexed for MEDLINE]

Limb remote ischemic per-conditioning in combination with post-conditioning reduces brain damage and promotes neuroglobin expression in the rat brain after ischemic stroke.

Sat, 07/02/2016 - 06:32
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Limb remote ischemic per-conditioning in combination with post-conditioning reduces brain damage and promotes neuroglobin expression in the rat brain after ischemic stroke.

Restor Neurol Neurosci. 2015;33(3):369-79

Authors: Ren C, Wang P, Wang B, Li N, Li W, Zhang C, Jin K, Ji X

Abstract
PURPOSE: Limb remote ischemic per-conditioning or post-conditioning has been shown to be neuroprotective after cerebral ischemic stroke. However, the effect of combining remote per-conditioning with post-conditioning on ischemic/reperfusion injury as well as the underlying mechanisms are largely unexplored.
METHODS: Here, adult male Sprague Dawley rats were subjected to middle cerebral artery occlusion (MCAO). The limb ischemic stimulus was immediately applied after onset of focal ischemia (per-conditioning), followed by repeated short episodes of remote ischemia 24 hr after reperfusion (post-conditioning). The infarct volume, motor function, and the expression of neuroglobin (Ngb) were measured at different durations after reperfusion.
RESULTS: We found that a single episode of limb remote per-conditioning afforded short-term protection, but combining repeated remote post-conditioning during the 14 days after reperfusion significantly ameliorated cerebral ischemia/reperfusion injury. Interestingly, we also found that ischemic per- and post-conditioning significantly increased expression of Ngb, an oxygen-binding globin protein that has been demonstrated to be neuroprotective against stroke, at peri-infarct regions from day 1 to day 14 following ischemia/reperfusion.
CONCLUSION: Our results suggest that the conventional per-conditioning combined with post-conditioning may be used as a novel neuroprotective strategy against ischemia-reperfusion injury, and Ngb seems to be one of the important players in limb remote ischemia-mediated neuroprotection.

PMID: 25868435 [PubMed - indexed for MEDLINE]

Surface Projection of Interosseous Foramen of the Leg - Cadaver Study: 696 Board #12 June 1, 3: 30 PM - 5: 00 PM.

Fri, 07/01/2016 - 06:31

Surface Projection of Interosseous Foramen of the Leg - Cadaver Study: 696 Board #12 June 1, 3: 30 PM - 5: 00 PM.

Med Sci Sports Exerc. 2016 May;48(5S Suppl 1):185-186

Authors: Arguello E, Richardson M, Stoddard C, Hartis A, Liu H

PMID: 27359839 [PubMed - as supplied by publisher]

Population pharmacokinetics of tenofovir in HIV-1 uninfected members of sero-discordant couples and effect of dose reporting methods.

Thu, 06/30/2016 - 10:30

Population pharmacokinetics of tenofovir in HIV-1 uninfected members of sero-discordant couples and effect of dose reporting methods.

Antimicrob Agents Chemother. 2016 Jun 27;

Authors: Lu Y, Goti V, Chaturvedula A, Haberer JE, Fossler MJ, Sale ME, Bangsberg D, Baeten JM, Celum CL, Hendrix CW

Abstract
Antiretroviral pre-exposure prophylaxis (PrEP) was shown to be effective for preventing HIV-1 infection in individuals who had HIV-1 seropositive partners (the Partners PrEP Study) with once daily dosing of tenofovir and tenofovir/emtricitabine. We developed a population pharmacokinetic model for tenofovir and investigated the impact of different dose reporting methods. Dosing information was collected by patient-reported dosing information (PRDI) from 404 subjects (corresponding to 1280 drug concentration records) from the main trial and electronic monitoring based adherence collected from 211 subjects (corresponding to 327 drug concentration records) in an ancillary adherence study. Model development was conducted with NONMEM (7.2) using PRDI with a steady-state assumption or using PRDI substituted with electronic monitoring records where available. A two-compartment model with first-order absorption was the best model from both modeling approaches with a need of absorption lag time when including electronic monitoring based dosing records in the analysis. Age, body weight and creatinine clearance were significant covariates on clearance, but only creatinine clearance was retained in the final models per stepwise selection. Sex was not a significant covariate on clearance. Tenofovir population pharmacokinetic parameter estimates and precision of the parameters from the two final models were comparable with the point estimates of the parameters differing from 0% to 35% and bootstrap confidence intervals widely overlapping. These findings indicate that the PRDI was sufficient for population pharmacokinetic model development in this study, with high level of adherence per multiple measures.

PMID: 27353269 [PubMed - as supplied by publisher]

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