Sexual behavior in male rodents

The hormonal factors and neural circuitry that control copulation are similar across rodent species, although there are differences in specific behavior patterns. Both estradiol (E) and dihydrotestosterone (DHT) contribute to the activation of mating, although E is more important for copulation and DHT for genital reflexes. Hormonal activation of the medial preoptic area (MPOA) is most effective, although implants in the medial amygdala (MeA) can also stimulate mounting in castrates. Chemosensory inputs from the main and accessory olfactory systems are the most important stimuli for mating in rodents, especially in hamsters, although genitosensory input also contributes. Dopamine agonists facilitate sexual behavior, and serotonin (5-HT) is generally inhibitory, though certain 5-HT receptor subtypes facilitate erection or ejaculation. Norepinephrine agonists and opiates have dose-dependent effects, with low doses facilitating and high doses inhibiting behavior.     

The evolution of multicellularity and early animal genomes

Several independent molecular datasets, including complete mtDNA sequence, indicate that Choanozoa are most closely related to multicellular animals. There is still confusion concerning basal animal phylogeny, although recent data indicate that Placozoa are not degenerate cnidarians and hence (along with sponges) occupy a pivotal position. The transition in evolution from diploblast to bilaterian animals is becoming better understood, with gene expression data arguing that cnidarians have forerunners of the anteroposterior and dorsoventral body axes, and even a putative homologue of mesoderm. The homeobox and kinase gene families have been further analysed in basal animals, although more data are required to enable detailed comparison with Bilateria.     

Nuclear organization of DNA replication initiation proteins in mammalian cells.

Origin recognition complex (ORC), CDC6, and MCM proteins assemble sequentially to form prereplication chromatin. However, their organization remains largely unclear in mammalian cells. Here we show that ORC1 proteins are associated with non-chromatin nuclear structures and assemble in nuclear foci in mammalian cells using an in vivo chemical cross-linking method. CDC6 proteins were also found to assemble in nuclear foci on non-chromatin nuclear structures, although their physical association with ORC1 has been undetectable. In contrast to the situation in yeast cells, CDC6 was found to remain associated with non-chromatin nuclear structures even after cells entered into S phase. Instead, ORC1 proteins were found to be degraded by a proteasome-dependent pathway during S phase. We also found that some ORC2 proteins are associated with non-chromatin nuclear structures like ORC1, although the remainder binds to nuclease-sensitive chromatin. Further analyses indicate that ORC2 physically interacts with ORC1 on non-chromatin nuclear structures. On the other hand, our results suggest that although a small proportion of MCM complexes are loaded onto chromatin regions near ORC foci, most of them are more widely distributed. Possible relations between such organization of prereplication chromatin and complicated origin specification in higher eukaryotic cells are discussed.     

An increase in the abundance of anchovies and sardines in the north-western North Sea since 1995

Trawl data from Scottish research vessels dating from January 1925 show that catches of the warm water pelagic species, anchovy ( Engraulis encrasicholus ) and sardine ( Sardina pilchardus ), increased suddenly after 1995. Most were observed in the first quarter of each year, with 1998 and 2003 having the largest numbers, although few data are available for the last quarter. The authors believe that these long-term changes are related to rising sea temperatures although the exact causal mechanism is not clear.     

Hydrogen bonding in DNA base complexes.

Experimental intermolecular frequencies in the DNA base complexes 1-methylthymine (1-MT) and cytosine monohydrate (CMH) are analyzed in terms of simple analytic interatomic potentials. Calculations with two different values for the constants of the nonbonded interactions are considered, and the hydrogen bond potentials are determined for each of these models. The observed frequencies in 1-MT are reasonably well described, although corresponding potentials are very different in the two models. The observed frequencies in CMH are less well described, although corresponding hydrogen bond potentials are similar in the two models. Hydration interactions are found to be important in CMH and the role of the water molecule is discussed. Possible reasons for the shortcomings of this simple analysis are considered.     

L-thyroxine and L-triiodothyronine in the cerebral tissues of the adult rat. Effect of hypothyroidism]

The L-thyroxine and L-triiodothyronine concentrations in several brain areas (cerebral cortex, brain stem, hypothalamus, total brain and hypophysis) in normal and hypothyroid rats have been studied. Results show that L-thyroxine values at tissue level are inferior in the hypothyroid group, although non-significant with respect to the control group, whereas L-triiodothyronine presents values similar to the hypothyroid group and its control in all the brain regions studied with the exception of hypophysis. These results show that in hypothyroid situations exist a compensatory mechanism for maintaining the adequate L-triiodothyronine levels in several brain areas, although the serum levels are strongly decreased in hypothyroid animals.     

Co-solubility in binary phospholipid crystals

Crystalline binary solid solutions of phosphatidylethanolamines are obtained when various fractions of compounds with different chain lengths are dissolved in chloroform and allowed to evaporate to dryness. Phase diagrams and electron diffraction measurements on chain mixtures with a difference of two or four methylene groups indicate that solubility is continuous, although non-ideal. Average molecular volume appears to increase according to Vegard's rule although deviations are noted. These deviations are similar to those observed for binary paraffin solids. Substitution of ether-links for ester-links in one component does not alter solubility behavior. In general the rules of solid solution formation appear to conform to those originally proposed by Kitaigorodskii [1961) Organic Chemical Crystallography, pp. 231-240, Consultants Bureau, New York).     

The birefringence of the human red cell ghosts

The type of birefringence described by Mitchison, which extends some 0.5 µ in from the surface of the human red cell ghost in glycerol and which shows a maximum retardation of about 7 A, is only found in ghosts which are sufficiently well hemoglobinised to be seen with the ordinary microscope. Ghosts from which all hemoglobin has been lost are not visible with the ordinary microscope and are not birefringent, although they are clearly visible with phase contrast. About 90 per cent of the ghosts in glycerol preparations are of the latter type, the exact percentage being a function of time. Mitchison's measurements of birefringence, although reproducible, accordingly apply only to ghosts in which some hemoglobin still remains complexed with the lipoprotein layers of the red cell ultrastructure, and do not enable one to draw conclusions as to the thickness and orientation of the lipoprotein surface layers.     

Echocardiography and cardiac resynchronisation therapy,friends or foes?

Echocardiography is used in cardiac resynchronisation therapy (CRT) to assess cardiac function, and in particular left ventricular (LV) volumetric status, and prediction of response. Despite its widespread applicability, LV volumes determined by echocardiography have inherent measurement errors, interobserver and intraobserver variability, and discrepancies with the gold standard magnetic resonance imaging. Echocardiographic predictors of CRT response are based on mechanical dyssynchrony. However, parameters are mainly tested in single-centre studies or lack feasibility. Speckle tracking echocardiography can guide LV lead placement, improving volumetric response and clinical outcome by guiding lead positioning towards the latest contracting segment. Results on optimisation of CRT device settings using echocardiographic indices have so far been rather disappointing, as results suffer from noise. Defining response by echocardiography seems valid, although re-assessment after 6 months is advisable, as patients can show both continuous improvement as well as deterioration after the initial response. Three-dimensional echocardiography is interesting for future implications, as it can determine volume, dyssynchrony and viability in a single recording, although image quality needs to be adequate. Deformation patterns from the septum and the derived parameters are promising, although validation in a multicentre trial is required. We conclude that echocardiography has a pivotal role in CRT, although clinicians should know its shortcomings.     

Bordetella pertussis, molecular pathogenesis under multiple aspects

Recent studies, including those based on genomics, have demonstrated that besides toxins and adhesins, Bordetella pertussis uses many additional virulence determinants. Most of them are part of the BvgAS regulon, although some, in particular iron-uptake systems, are independent of BvgAS. They are regulated by iron, although in one case, the production of a siderophore receptor could be linked to the BvgAS regulon.     

Does either the gastrointestinal peptide PYY or the neuropeptide NPY bind aluminium?

Peptide YY and neuropeptide Y are common peptides with a high degree of primary and tertiary structural homology. They are multifunctional and participate in a diverse array of distinct activities including regulation of gastrointestinal function and neural regulation of satiety. Recently both have been implicated in aluminium chemistry in vivo although their modus opperandi have not been determined. We have used molecular fluorescence, RP-HPLC, ESMS and equilibrium dialysis to identify if either peptide YY or neuropeptide Y will bind aluminium in vitro under near-physiological conditions. We were unable to demonstrate any direct interaction between either peptide and aluminium although we have speculated upon an in vivo mechanism whereby PYY, in particular, might form a stable complex with aluminium.     

A phylogeny of fossil and living neocoleoid cephalopods

Coleoid cephalopod phylogeny is well studied via both molecular and morphological data, yet although some agreement has been reached (e.g. that extant Decapodiformes and Octopoda are monophyletic) many details remain poorly resolved. Fossil coleoids, for which much data exists, have hitherto not been incorporated into analyses. Their inclusion is highly desirable for the support of neontological phylogenies, to better reconstruct character‐state histories, and to investigate the placement of the fossil groups themselves. In this study we present and analyse a morphological data matrix including both extinct and extant taxa. Homology assumptions in our data are discussed. Our results are presented both with and without the constraint of a monophyletic Decapodiformes imposed. When analysed with this constraint our results are strikingly congruent with those from molecular phylogeny, for instance placing Idiosepius in a basal position within Decapodiformes, and recovering Oegopsida and Bathyteuthoidea (although as grades). Our results support an Octopodiformes clade (“vampire squid” Vampyroteuthis as sister to Octopoda) and an octopodiform interpretation for most fossil coleoids. They suggest the fossil sister taxon to the octopods to be Plesioteuthididae. Most fossil higher taxa are supported, although many genera, especially within suborder Teudopseina, appear para‐ or polyphyletic.     

Biotransformation of phenolic compounds by Bacillus aryabhattai

Bioprocess and Biosystems Engineering - Phenolic compounds could pose environmental problems if they are in excess, although they could be a renewable resource of substances with industrial...     

Spondyloarthritides: evolving therapies

TNF blockade therapy has substantially advanced the treatment of peripheral spondyloarthritides but revolutionised the treatment of severe ankylosing spondylitis. The capacity of biologic treatment to improve dramatically symptoms and quality of life in patients with spinal disease is undoubted, although important questions remain. Notable amongst these are concerns about skeletal disease modification and the true balance between costs and effectiveness. Guidelines for the biologic treatment of ankylosing spondylitis and psoriatic arthritis have been introduced in North America and Europe with considerable consensus. However, the absence of clear criteria for the diagnosis of early disease leaves the issue of biologic treatment of ankylosing spondylitis at the pre-radiographic stage unresolved. Newer biologic agents are entering the field, although superiority over TNF blockers will be difficult to demonstrate.     

Reduced performance of prey targeting in pit vipers with contralaterally occluded infrared and visual senses

Both visual and infrared (IR) senses are utilized in prey targeting by pit vipers. Visual and IR inputs project to the contralateral optic tectum where they activate both multimodal and bimodal neurons. A series of ocular and pit organ occlusion experiments using the short-tailed pit viper (Gloydius brevicaudus) were conducted to investigate the role of visual and IR information during prey targeting. Compared with unoccluded controls, snakes with either both eyes or pit organs occluded performed more poorly in hunting prey although such subjects still captured prey on 75% of trials. Subjects with one eye and one pit occluded on the same side of the face performed as well as those with bilateral occlusion although these subjects showed a significant targeting angle bias toward the unoccluded side. Performance was significantly poorer when only a single eye or pit was available. Interestingly, when one eye and one pit organ were occluded on opposite sides of the face, performance was poorest, the snakes striking prey on no more than half the trials. These results indicate that, visual and infrared information are both effective in prey targeting in this species, although interference between the two modalities occurs if visual and IR information is restricted to opposite sides of the brain.     

Ectomycorrhizal Associations of the Dipterocarpaceae

Dipterocarps are one of the most important tree families in the lowland forests of Southeast Asia and are somewhat unusual among tropical trees in that they form ectomycorrhizal (EcM) symbiotic root‐inhabiting fungal associations. It has been hypothesized that dipterocarps have been partnered in this mutualistic association prior to the separation of Gondwana. Under many conditions EcMs form rapidly on dipterocarp seedlings through inocula present in the soil, although few studies have been conducted to provide evidence that they improve seedling establishment and performance. There are hundreds of EcM species associated with dipterocarps. Fungal fruit body surveys suggest that the most important families are Amanitaceae, Boletaceae, and Russulaceae, although Thelephoraceae also become numerically important when root tips are examined. EcM communities are affected by various biotic and abiotic factors, as well as anthropogenic perturbations, and the importance of these in structuring EcM communities is examined herein.     

A review of non-cancer effects, especially circulatory and ocular diseases

There is a well-established association between high doses (>5 Gy) of ionizing radiation exposure and damage to the heart and coronary arteries, although only recently have studies with high-quality individual dosimetry been conducted that would enable quantification of this risk adjusting for concomitant chemotherapy. The association between lower dose exposures and late occurring circulatory disease has only recently begun to emerge in the Japanese atomic bomb survivors and in various occupationally exposed cohorts and is still controversial. Excess relative risks per unit dose in moderate- and low-dose epidemiological studies are somewhat variable, possibly a result of confounding and effect modification by well-known (but unobserved) risk factors. Radiation doses of 1 Gy or more are associated with increased risk of posterior subcapsular cataract. Accumulating evidence from the Japanese atomic bomb survivors, Chernobyl liquidators, US astronauts, and various other exposed groups suggests that cortical cataracts may also be associated with ionizing radiation, although there is little evidence that nuclear cataracts are radiogenic. The dose–response appears to be linear, although modest thresholds (of no more than about 0.6 Gy) cannot be ruled out. A variety of other non-malignant effects have been observed after moderate/low-dose exposure in various groups, in particular respiratory and digestive disease and central nervous system (and in particular neuro-cognitive) damage. However, because these are generally only observed in isolated groups, or because the evidence is excessively heterogeneous, these associations must be treated with caution.     

Renal Failure in Cirrhosis of the Liver

The clinical course and autopsy findings of three patients with acute renal failure terminating the course of cirrhosis of the liver are presented. Review of the literature demonstrated that where decompensated cirrhosis is present the renal blood flow is characteristically low, although the total cardiac output is elevated. This circulatory disturbance results in the production of urine low in sodium, although normal in solute content. It also renders the kidney more vulnerable to further, sometimes minor, reductions in renal blood flow. As more patients with hepatic cirrhosis live through episodes of gastrointestinal bleeding and hepatic coma, death in acute renal failure will undoubtedly become more common.