Nucleotide sequence of mouse 5-aminolevulinic acid synthase cDNA and expression of its gene in hepatic and erythroid tissues

The cDNA coding for 5-aminolevulinic acid (ALA) synthase (EC 2.3.1.37) in both liver and anemic spleen of the mouse has been cloned. The liver clone was selected by complementation of an Escherichia coli hemA mutant. Erythroid clones were obtained by screening a cDNA library made from mouse anemic spleen RNA, using the liver cDNA as a probe. The sequences of the spleen-derived and liver-derived cDNAs are identical. The nucleotide sequence and predicted amino acid (aa) sequence of a 1.85-kb spleen-derived cDNA is presented. The mouse ALA synthase as sequence displays extensive homology to ALA synthase of chick embryonic liver. The ALA synthase mRNA, detected by Northern blot analysis, was the same size, approx. 2.3 kb, in mouse liver, anemic spleen, and mouse erythroleukemia cells. It is therefore unlikely that different isozymic forms of ALA synthase are present in mouse erythroid and hepatic tissue and this is not the basis for the different effects of heme and porphyrinogenic compounds on the expression of liver and erythroid ALA synthase.     

Tricyclic aminopyrimidine histamine H4 receptor antagonists

This report discloses the development of a series of tricyclic histamine H(4) receptor antagonists. Starting with a low nanomolar benzofuranopyrimidine HTS hit devoid of pharmaceutically acceptable properties, we navigated issues with metabolism and solubility to furnish a potent, stable and water soluble tricyclic histamine H(4) receptor antagonist with desirable physiochemical parameters which demonstrated efficacy a mouse ova model.     

Are Neoclassical Canons Valid for Southern Chinese Faces?

Background

Proportions derived from neoclassical canons, initially described by Renaissance sculptors and painters, are still being employed as aesthetic guidelines during the clinical assessment of the facial morphology.

Objective

1. to determine the applicability of neoclassical canons for Southern Chinese faces and 2. to explore gender differences in relation to the applicability of the neoclassical canons and their variants.

Methodology

3-D photographs acquired from 103 young adults (51 males and 52 females) without facial dysmorphology were used to test applicability of four neoclassical canons. Standard anthropometric measurements that determine the facial canons were made on these 3-D images. The validity of the canons as well as their different variants were quantified.

Principal Findings

The neoclassical cannons seldom applied to these individuals, and facial three-section and orbital canons did not apply at all. The orbitonasal canon was most frequently applicable, with a frequency of 19%. Significant sexual dimorphism was found relative to the prevalence of the variants of facial three-section and orbitonasal canons.

Conclusion

The neoclassical canons did not appear to apply to our sample when rigorous quantitative measurements were employed. Thus, they should not be used as esthetic goals for craniofacial surgical interventions.     

High Abundances of Potentially Active Ammonia-Oxidizing Bacteria and Archaea in Oligotrophic,High-Altitude Lakes of the Sierra Nevada,California, USA

Nitrification plays a central role in the nitrogen cycle by determining the oxidation state of nitrogen and its subsequent bioavailability and cycling. However, relatively little is known about the underlying ecology of the microbial communities that carry out nitrification in freshwater ecosystems—and particularly within high-altitude oligotrophic lakes, where nitrogen is frequently a limiting nutrient. We quantified ammonia-oxidizing archaea (AOA) and bacteria (AOB) in 9 high-altitude lakes (2289–3160 m) in the Sierra Nevada, California, USA, in relation to spatial and biogeochemical data. Based on their ammonia monooxygenase (amoA) genes, AOB and AOA were frequently detected. AOB were present in 88% of samples and were more abundant than AOA in all samples. Both groups showed >100 fold variation in abundance between different lakes, and were also variable through time within individual lakes. Nutrient concentrations (ammonium, nitrite, nitrate, and phosphate) were generally low but also varied across and within lakes, suggestive of active internal nutrient cycling; AOB abundance was significantly correlated with phosphate (r² = 0.32, p<0.1), whereas AOA abundance was inversely correlated with lake elevation (r² = 0.43, p<0.05). We also measured low rates of ammonia oxidation—indicating that AOB, AOA, or both, may be biogeochemically active in these oligotrophic ecosystems. Our data indicate that dynamic populations of AOB and AOA are found in oligotrophic, high-altitude, freshwater lakes.     

A meta-analysis of elevated [CO2] effects on soybean (Glycine max) physiology, growth and yield

The effects of elevated [CO₂] on 25 variables describing soybean physiology, growth and yield are reviewed using meta‐analytic techniques. This is the first meta‐analysis to our knowledge performed on a single crop species and summarizes the effects of 111 studies. These primary studies include numerous soybean growth forms, various stress and experimental treatments, and a range of elevated [CO₂] levels (from 450 to 1250 p.p.m.), with a mean of 689 p.p.m. across all studies. Stimulation of soybean leaf CO₂ assimilation rate with growth at elevated [CO₂] was 39%, despite a 40% decrease in stomatal conductance and a 11% decrease in Rubisco activity. Increased leaf CO₂ uptake combined with an 18% stimulation in leaf area to provide a 59% increase in canopy photosynthetic rate. The increase in total dry weight was lower at 37%, and seed yield still lower at 24%. This shows that even in an agronomic species selected for maximum investment in seed, several plant level feedbacks prevent additional investment in reproduction, such that yield fails to reflect fully the increase in whole plant carbon uptake. Large soil containers (> 9 L) have been considered adequate for assessing plant responses to elevated [CO₂]. However, in open‐top chamber experiments, soybeans grown in large pots showed a significant threefold smaller stimulation in yield than soybeans grown in the ground. This suggests that conclusions about plant yield based on pot studies, even when using very large containers, are a poor reflection of performance in the absence of any physical restriction on root growth. This review supports a number of current paradigms of plant responses to elevated [CO₂]. Namely, stimulation of photosynthesis is greater in plants that fix N and have additional carbohydrate sinks in nodules. This supports the notion that photosynthetic capacity decreases when plants are N‐limited, but not when plants have adequate N and sink strength. The root : shoot ratio did not change with growth at elevated [CO₂], sustaining the charge that biomass allocation is unaffected by growth at elevated [CO₂] when plant size and ontogeny are considered.     

Na-K-Cl cotransporter-1 in the mechanism of cell swelling in cultured astrocytes after fluid percussion injury

Brain edema and associated increased intracranial pressure are major consequences of traumatic brain injury (TBI). An important early component of the edema associated with TBI is astrocyte swelling (cytotoxic edema). Mechanisms for such swelling, however, are poorly understood. Ion channels/transporters/exchangers play a major role in cell volume regulation, and a disturbance in one or more of these systems may result in cell swelling. To examine potential mechanisms in TBI-mediated brain edema, we employed a fluid percussion model of in vitro barotrauma and examined the role of the ion transporter Na(+)-K(+)-2Cl(-)-cotransporter 1 (NKCC1) in trauma-induced astrocyte swelling as this transporter has been strongly implicated in the mechanism of cell swelling in various neurological conditions. Cultures exposed to trauma (3, 4, 5 atm pressure) caused a significant increase in NKCC1 activity (21%, 42%, 110%, respectively) at 3 h. At 5 atm pressure, trauma significantly increased NKCC1 activity at 1 h and it remained increased for up to 3 h. Trauma also increased the phosphorylation (activation) of NKCC1 at 1 and 3 h. Inhibition of MAPKs and oxidative/nitrosative stress diminished the trauma-induced NKCC1 phosphorylation as well as its activity. Bumetanide, an inhibitor of NKCC1, significantly reduced the trauma-induced astrocyte swelling (61%). Silencing NKCC1 with siRNA led to a reduction in trauma-induced NKCC1 activity as well as in cell swelling. These findings demonstrate the critical involvement of NKCC1 in the astrocyte swelling following in vitro trauma, and suggest that blocking NKCC1 activity may represent a useful therapeutic strategy for the cytotoxic brain edema associated with the early phase of TBI.     

A case of mistaken identity: skin filaments are unreliable for identifying Hippocampus guttulatus and Hippocampus hippocampus

The presence or absence of skin filaments is an unreliable character for identifying European seahorses. Growth of skin filaments on Hippocampus guttulatus coincides with maturation, while presence on Hippocampus hippocampus is highly variable. Multiple morphological traits including snout, head and trunk shape should be used for identification.     

The Role of Sirt1 in Bile Acid Regulation during Calorie Restriction in Mice

Sirtuin 1 (Sirt1) is an NAD⁺-dependent protein deacetylase that is proposed to mediate many health-promoting effects of calorie restriction (CR). We recently reported that short-term CR increased the bile acid (BA) pool size in mice, likely due to increased BA synthesis in liver. Given the important role of Sirt1 in the regulation of glucose, lipid, as well as BA metabolism, we hypothesized that the CR-induced increase in BAs is Sirt1-dependent. To address this, the present study utilized genetically-modified mice that were Sirt1 loss of function (liver knockout, LKO) or Sirt1 gain of function (whole body-transgenic, TG). Three genotypes of mice (Sirt1-LKO, wild-type, and Sirt1-TG) were each randomly divided into ad libitum or 40% CR feeding for one month. BAs were extracted from various compartments of the enterohepatic circulation, followed by BA profiling by UPLC-MS/MS. CR increased the BA pool size and total BAs in serum, gallbladder, and small intestine. The CR-induced increase in BA pool size correlated with the tendency of increase in the expression of the rate-limiting BA-synthetic enzyme Cyp7a1. However, in contrast to the hypothesis, the CR-induced increase in BA pool size and Cyp7a1 expression was still observed with ablated expression of Sirt1 in liver, and completely suppressed with whole-body overexpression of Sirt1. Furthermore, in terms of BA composition, CR increased the ratio of 12α-hydroxylated BAs regardless of Sirt1 genotypes. In conclusion, the CR-induced alterations in BA pool size, BA profiles, and expression of BA-related genes do not appear to be dependent on Sirt1.     

Heat stability and allosteric properties of the maize endosperm ADP-glucose pyrophosphorylase are intimately intertwined

ADP-glucose (Glc) pyrophosphorylase (AGPase), a key regulatory enzyme in starch biosynthesis, is highly regulated. Transgenic approaches in four plant species showed that alterations in either thermal stability or allosteric modulation increase starch synthesis. Here, we show that the classic regulators 3-phosphoglyceric acid (3-PGA) and inorganic phosphate (Pi) stabilize maize (Zea mays) endosperm AGPase to thermal inactivation. In addition, we show that glycerol phosphate and ribose-5-P increase the catalytic activity of maize AGPase to the same extent as the activator 3-PGA, albeit with higher K(a) (activation constant) values. Activation by fructose-6-P and Glc-6-P is comparable to that of 3-PGA. The reactants ATP and ADP-Glc, but not Glc-1-P and pyrophosphate, protect AGPase from thermal inactivation, a result consistent with the ordered kinetic mechanism reported for other AGPases. 3-PGA acts synergistically with both ATP and ADP-Glc in heat protection, decreasing the substrate concentration needed for protection and increasing the extent of protection. Characterization of a series of activators and inhibitors suggests that they all bind at the same site or at mutually exclusive sites. Pi, the classic "inhibitor" of AGPase, binds to the enzyme in the absence of other metabolites, as determined by thermal protections experiments, but does not inhibit activity. Rather, Pi acts by displacing bound activators and returning the enzyme to its activity in their absence. Finally, we show from thermal inactivation studies that the enzyme exists in two forms that have significantly different stabilities and do not interconvert rapidly.