Role of α- and ß-adrenergic signaling in phenotypic targeting: significance in benign and malignant urologic disease.

The urinary tract is highly innervated by autonomic nerves which are essential in urinary tract development, the production of growth factors, and the control of homeostasis. These neural signals may become dysregulated in several genitourinary (GU) disease states, both benign and malignant. Accordingly, the autonomic nervous system is a therapeutic target for several genitourinary pathologies including cancer, voiding dysfunction, and obstructing nephrolithiasis. Adrenergic receptors (adrenoceptors) are G-Protein coupled-receptors that are distributed throughout the body. The major function of α1-adrenoceptors is signaling smooth muscle contractions through GPCR and intracellular calcium influx. Pharmacologic intervention of α-and ß-adrenoceptors is routinely and successfully implemented in the treatment of benign urologic illnesses, through the use of α-adrenoceptor antagonists. Furthermore, cell-based evidence recently established the antitumor effect of α1-adrenoceptor antagonists in prostate, bladder and renal tumors by reducing neovascularity and impairing growth within the tumor microenvironment via regulation of the phenotypic epithelial-mesenchymal transition (EMT). There has been a significant focus on repurposing the routinely used, Food and Drug Administration-approved α1-adrenoceptor antagonists to inhibit GU tumor growth and angiogenesis in patients with advanced prostate, bladder, and renal cancer. In this review we discuss the current evidence on (a) the signaling events of the autonomic nervous system mediated by its cognate α- and ß-adrenoceptors in regulating the phenotypic landscape (EMT) of genitourinary organs; and (b) the therapeutic significance of targeting this signaling pathway in benign and malignant urologic disease. Video abstract.

Association of rare missense variants in the second intracellular loop of NaV1.7 sodium channels with familial autism.

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder often accompanied by intellectual disability, language impairment and medical co-morbidities. The heritability of autism is high and multiple genes have been implicated as causal. However, most of these genes have been identified in de novo cases. To further the understanding of familial autism, we performed whole-exome sequencing on five families in which second- and third-degree relatives were affected. By focusing on novel and protein-altering variants, we identified a small set of candidate genes. Among these, a novel private missense C1143F variant in the second intracellular loop of the voltage-gated sodium channel NaV1.7, encoded by the SCN9A gene, was identified in one family. Through electrophysiological analysis, we show that NaV1.7C1143F exhibits partial loss-of-function effects, resulting in slower recovery from inactivation and decreased excitability in cultured cortical neurons. Furthermore, for the same intracellular loop of NaV1.7, we found an excess of rare variants in a case-control variant-burden study. Functional analysis of one of these variants, M932L/V991L, also demonstrated reduced firing in cortical neurons. However, although this variant is rare in Caucasians, it is frequent in Latino population, suggesting that genetic background can alter its effects on phenotype. Although the involvement of the SCN1A and SCN2A genes encoding NaV1.1 and NaV1.2 channels in de novo ASD has previously been demonstrated, our study indicates the involvement of inherited SCN9A variants and partial loss-of-function of NaV1.7 channels in the etiology of rare familial ASD.

Effects of bait age, larval chemical cues and nutrient depletion on colonization by forensically important Calliphorid and Sarcophagid flies.

Species colonization patterns on corpses and the frequency of carrion fly oviposition and larviposition are affected by decomposition stage and previous maggot colonization. This study investigated these effects on meat bait colonization by Victorian Diptera of forensic importance. Bait treatments were: 'aged' (aged for 4 days at 22 °C, allowing some decomposition); 'nutrient-depleted' [aged for 4 days at 22 °C with feeding Calliphora vicina (Robineau-Desvoidy) (Diptera: Calliphoridae) larvae]; 'extract' (fresh bait mixed with liquid formed by feeding C. vicina larvae), and 'fresh' (untreated control bait). Statistical analysis (α = 0.05) revealed that colonization frequency differed significantly among treatments (Welch's F(3,18.83) = 4.66, P < 0.05). Post hoc tests showed that fresh and extract baits were colonized extensively throughout the experiment with no significant difference, whereas the colonization of nutrient-depleted baits was significantly lower. This suggests that larval digestive enzymes, larval excreta and cuticular hydrocarbons have less effect on colonizing Diptera than the nutritional content of meat. The colonization of aged baits did not differ significantly from that of fresh, extract or nutrient-depleted baits. A further experiment testing 'very aged' (aged for 8 days at 28 °C), 'larvae-added' (fresh bait with C. vicina larvae added before placement) and 'fresh' (untreated control) baits revealed that very aged baits were colonized significantly less frequently than either fresh or larvae-added baits (Welch's F(2, 6.17) = 17.40, P < 0.05).

How a Realistic Magnetosphere Alters the Polarizations of Surface, Fast Magnetosonic, and Alfvén Waves.

System-scale magnetohydrodynamic (MHD) waves within Earth's magnetosphere are often understood theoretically using box models. While these have been highly instructive in understanding many fundamental features of the various wave modes present, they neglect the complexities of geospace such as the inhomogeneities and curvilinear geometries present. Here, we show global MHD simulations of resonant waves impulsively excited by a solar wind pressure pulse. Although many aspects of the surface, fast magnetosonic (cavity/waveguide), and Alfvén modes present agree with the box and axially symmetric dipole models, we find some predictions for large-scale waves are significantly altered in a realistic magnetosphere. The radial ordering of fast mode turning points and Alfvén resonant locations may be reversed even with monotonic wave speeds. Additional nodes along field lines that are not present in the displacement/velocity occur in both the perpendicular and compressional components of the magnetic field. Close to the magnetopause, the perpendicular oscillations of the magnetic field have the opposite handedness to the velocity. Finally, widely used detection techniques for standing waves, both across and along the field, can fail to identify their presence. We explain how all these features arise from the MHD equations when accounting for a non-uniform background field and propose modified methods that might be applied to spacecraft observations.

Magnetopause ripples going against the flow form azimuthally stationary surface waves.

Surface waves process the turbulent disturbances which drive dynamics in many space, astrophysical and laboratory plasma systems, with the outer boundary of Earth's magnetosphere, the magnetopause, providing an accessible environment to study them. Like waves on water, magnetopause surface waves are thought to travel in the direction of the driving solar wind, hence a paradigm in global magnetospheric dynamics of tailward propagation has been well-established. Here we show through multi-spacecraft observations, global simulations, and analytic theory that the lowest-frequency impulsively-excited magnetopause surface waves, with standing structure along the terrestrial magnetic field, propagate against the flow outside the boundary. Across a wide local time range (09-15h) the waves' Poynting flux exactly balances the flow's advective effect, leading to no net energy flux and thus stationary structure across the field also. Further down the equatorial flanks, however, advection dominates hence the waves travel downtail, seeding fluctuations at the resonant frequency which subsequently grow in amplitude via the Kelvin-Helmholtz instability and couple to magnetospheric body waves. This global response, contrary to the accepted paradigm, has implications on radiation belt, ionospheric, and auroral dynamics and potential applications to other dynamical systems.

A new order of tertiary zalambdodont marsupials.

Yalkaparidon coheni and Yalkaparidon jonesi are described here as the first-known members of the marsupial family Yalkaparidontidae and order Yalkaparidontia. Before discovery of these zalambdodont marsupials in unnamed Tertiary sediments from northwestern Queensland, only five orders of australidelphian marsupials were known. Dental and basicranial morphology suggest that notoryctids and yalkaparidontids, which both have highly specialized zalambdodont molars, are dentally convergent. Yalkaparidontids lived in lowland rainforests of northern Australia and appear to have vanished, with the rainforests, sometime in the middle to late Tertiary. Discovery of yalkaparidontids demonstrates a significantly greater breadth of diversity for Australian marsupials.

Environmental nitroso compounds: reaction of nitrite with creatine and creatinine.

Creatine reacts with nitrite under acid conditions to produce first sarcosine and then N-nitrososarcosine, which is a weak carcinogen in the rat. Creatinine reacts with acidified nitrite to produce either creatinine-5-oxime or 1-methylhydantoin-5-oxime, depending on reaction conditions. The toxicity and environmental significance of these compounds is not yet known.

Crystal structure of the xanthine oxidase-related aldehyde oxido-reductase from D. gigas.

The crystal structure of the aldehyde oxido-reductase (Mop) from the sulfate reducing anaerobic Gram-negative bacterium Desulfovibrio gigas has been determined at 2.25 A resolution by multiple isomorphous replacement and refined. The protein, a homodimer of 907 amino acid residues subunits, is a member of the xanthine oxidase family. The protein contains a molybdopterin cofactor (Mo-co) and two different [2Fe-2S] centers. It is folded into four domains of which the first two bind the iron sulfur centers and the last two are involved in Mo-co binding. Mo-co is a molybdenum molybdopterin cytosine dinucleotide. Molybdopterin forms a tricyclic system with the pterin bicycle annealed to a pyran ring. The molybdopterin dinucleotide is deeply buried in the protein. The cis-dithiolene group of the pyran ring binds the molybdenum, which is coordinated by three more (oxygen) ligands.

Daily rhythm in human urinary melatonin.

The melatonin in urine samples from six healthy adult volunteers was concentrated on Amberlite XAD-2 resin, eluted with organic solvents, and quantitated by use of a bioassay technique (the dermal melanaphore response of larval anurans to melatonin in their bathing medium). The melatonin content of samples collected between 11 p.m. and 7 a.m. was, in each case, several times higher than that of samples collected between 7 a.m. and 3 p.m. or between 3 p.m. and 11 p.m.

Direct observations of a surface eigenmode of the dayside magnetopause.

The abrupt boundary between a magnetosphere and the surrounding plasma, the magnetopause, has long been known to support surface waves. It was proposed that impulses acting on the boundary might lead to a trapping of these waves on the dayside by the ionosphere, resulting in a standing wave or eigenmode of the magnetopause surface. No direct observational evidence of this has been found to date and searches for indirect evidence have proved inconclusive, leading to speculation that this mechanism might not occur. By using fortuitous multipoint spacecraft observations during a rare isolated fast plasma jet impinging on the boundary, here we show that the resulting magnetopause motion and magnetospheric ultra-low frequency waves at well-defined frequencies are in agreement with and can only be explained by the magnetopause surface eigenmode. We therefore show through direct observations that this mechanism, which should impact upon the magnetospheric system globally, does in fact occur.

Genetic analysis of mechanisms of aging.

A wide range of genetic models with postponed aging are now available, from selected mice and Drosophilia to mutant Caenorhabditis elegans and Saccharomyces cerevisiae. These systems allow efficient testing of alternative mechanistic hypotheses for aging. Genetic analysis is forging stronger connections between particular alleles and susceptibility to particular 'diseases of aging'; for example, two different genes for Alzheimer disease have been identified.

p45(NFE2) is a negative regulator of erythroid proliferation which contributes to the progression of Friend virus-induced erythroleukemias.

In previous studies, we identified a common site of retroviral integration designated Fli-2 in Friend murine leukemia virus (F-MuLV)-induced erythroleukemia cell lines. Insertion of F-MuLV at the Fli-2 locus, which was associated with the loss of the second allele, resulted in the inactivation of the erythroid cell- and megakaryocyte-specific gene p45(NFE2). Frequent disruption of p45(NFE2) due to proviral insertion suggests a role for this transcription factor in the progression of Friend virus-induced erythroleukemias. To assess this possibility, erythroleukemia was induced by F-MuLV in p45(NFE2) mutant mice. Since p45(NFE2) homozygous mice mostly die at birth, erythroleukemia was induced in +/- and +/+ mice. We demonstrate that +/- mice succumb to the disease moderately but significantly faster than +/+ mice. In addition, the spleens of +/- mice were significantly larger than those of +/+ mice. Of the 37 tumors generated from the +/- and +/+ mice, 10 gave rise to cell lines, all of which were derived from +/- mice. Establishment in culture was associated with the loss of the remaining wild-type p45(NFE2) allele in 9 of 10 of these cell lines. The loss of a functional p45(NFE2) in these cell lines was associated with a marked reduction in globin gene expression. Expression of wild-type p45(NFE2) in the nonproducer erythroleukemic cells resulted in reduced cell growth and restored the expression of globin genes. Similarly, the expression of p45(NFE2) in these cells also slows tumor growth in vivo. These results indicate that p45(NFE2) functions as an inhibitor of erythroid cell growth and that perturbation of its expression contributes to the progression of Friend erythroleukemia.

Crystallization and preliminary structure determination of the membrane-bound complex cytochrome c nitrite reductase from Desulfovibrio vulgaris Hildenborough.

The cytochrome c nitrite reductase (cNiR) isolated from Desulfovibrio vulgaris Hildenborough is a membrane-bound complex formed of NrfA and NrfH subunits. The catalytic subunit NrfA is a soluble pentahaem cytochrome c that forms a physiological dimer of about 120 kDa. The electron-donor subunit NrfH is a membrane-anchored tetrahaem cytochrome c of about 18 kDa molecular weight and belongs to the NapC/NirT family of quinol dehydrogenases, for which no structures are known. Crystals of the native cNiR membrane complex, solubilized with dodecylmaltoside detergent (DDM), were obtained using PEG 4K as precipitant. Anomalous diffraction data were measured at the Swiss Light Source to 2.3 A resolution. Crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 79.5, b = 256.7, c = 578.2 A. Molecular-replacement and MAD methods were combined to solve the structure. The data presented reveal that D. vulgaris cNiR contains one NrfH subunit per NrfA dimer.

Deuterium isotope effect in the microsomal metabolism of dimethylnitrosamine.

The rates of N-demethylation of dimethylnitrosamine and dimethylnitrosamine-d6 by rat liver microsomes were studied by monitoring formaldehyde production. Deuterium isotope effects of 1.6 and 3.8 were found for the Michaelis constant and the maximum velocity, respectively.

Kinetics of nitrosamine formation in the presence of micelle-forming surfactants.

The nitrosation of dihexylamine by nitrite was catalyzed in the presence of micelles of the cationic surfactant decyltrimethylammonium bromide. Rate enhancements up to 800-fold were observed. The magnitude of the rate enhancements was dependent on the amine structure, particularly the alkyl chain length. Rate enhancements for nitrosation were also observed in the presence of micelles of phosphatidylcholine and Triton X-100. We present a mechanistic interpretation of these catalytic effects.

Cellular toxicity of pancreatic carcinogens.

Azaserine (CAS: 115-02-6), streptozocin (CAS: 18883-66-4; streptozotocin), and N-nitrosobis(2-oxopropyl)amine [(BOP) CAS: 60599-38-4] produce different types of pancreatic tumors in rodents. We have investigated the toxic effects of these compounds on pancreatic tissues from Wistar rats and Syrian hamsters. Inhibition of protein synthesis was used as a measure of toxicity. Pancreatic islets and acinar cells from rat and hamster were labeled with [3H]leucine for 60 minutes in vitro in the presence of the various carcinogens. Azaserine, which produces acinar cell tumors in the rat, inhibited synthesis by all tissues; rat acinar cells, however, were most sensitive. Glutamine, but not serine, provided some protection against azaserine toxicity. Streptozocin inhibited synthesis by islets of both species and acinar cells from hamster; islets were the most sensitive. BOP and N-nitroso(2-hydroxypropyl)(2-oxopropyl)amine, which induce ductal tumors in the hamster, had no effect on any of the tissues examined. These results indicate that the specificities of the cellular toxicities of the pancreatic carcinogens parallel, to some degree, their tumorigenic effects.

N-nitrosation of proline in smokers and nonsmokers.

Endogenous nitrosation of proline was investigated in smokers and nonsmokers. Volunteers consumed a volume of beet juice equivalent to 325 mg nitrate, and 1 hour later they consumed 500 mg proline. In separate experiments volunteers ingested proline alone. Twenty-four-hour urine samples were collected and analyzed for N-nitrosoproline. When proline alone was ingested, there was no significant difference in urinary nitrosoproline excretion between smokers and nonsmokers. When beet juice and proline were consumed, however, smokers produced approximately 2.5 times as much N-nitrosoproline as nonsmokers. Salivary thiocyanate levels were approximately 3.2 times higher in smokers compared to those in nonsmokers. Salivary nitrite levels of smokers and nonsmokers, either before or after beet juice consumption, were not different. Salivary nitrate concentrations, however, were higher in nonsmokers than in smokers after beet juice consumption but not before. Our results suggest that the higher level of salivary thiocyanate in smokers is responsible for the increased rate of endogenous nitrosation of proline in this group compared to the rate in nonsmokers. Nitrosating agents in cigarette smoke do not appear to play a significant role.

Kinetic studies on the hepatic microsomal metabolism of dimethylnitrosamine, diethylnitrosamine, and methylethylnitrosamine in the rat.

The oxidative dealkylation of dimethylnitrosamine (DMN), diethylnitrosamine (DEN), and methylethylnitrosamine (MEN) by Sprague-Dawley rat liver microsomes was studied by a colorimetric assay for the simultaneous analysis of formaldehyde and acetaldehyde. Dealkylation in each instance followed Michaelis-Menten kinetics, but the Michaelis constant (Km) for DEN was an order of magnitude smaller than the Km for DMN. Km values for demethylation and deethylation of MEN were intermediate between those for DMN and DEN. DMN inhibited-deethylase, and DEN inhibited DMN-demethylase activity. The inhibition was of a mixed type in both instances.

Induction and suppression of N-nitrosomethylbenzylamine activation by microsomes from rat liver and esophagus.

Male Sprague-Dawley rats were pretreated with various chemicals to determine their effects on the microsomal activation of the esophageal carcinogen N-nitrosomethylbenzylamine [( NMBzA ) CAS: 937-40-6; N-methyl-N- nitrosobenzylamine ] in the rat esophagus and, for comparative purposes, in the rat liver. When rats were pretreated with NMBzA , little change in hepatic NMBzA - debenzylase activity was observed. In contrast, NMBzA metabolism in the esophagus was significantly (60-65%) reduced. Similarly, pretreatment of rats with disulfiram [CAS: 97-77-8; bis( diethylthiocarbamoyl )disulfide] caused a 40% decrease in esophageal metabolism, but it had no significant effect in the liver. Pretreatments with the methylenedioxybenzenes safrole [CAS: 94-59-7; 4-allyl-1,2-(methylenedioxy)benzene], isosafrole [CAS: 120-58-1; 1,2-(methylenedioxy)-4-propenylbenzene], and dihydrosafrole (CAS: 94-58-6; 1,2-(methylenedioxy)-4- propylbenzene ) caused a marked induction (twofold to fivefold) of the hepatic metabolism of NMBzA , but again esophageal metabolism was suppressed. The results indicate that esophageal metabolism of NMBzA is either unchanged or suppressed by the various chemical pretreatments, but hepatic metabolism of the nitrosamine is induced by the methylenedioxybenzenes .