Cinnamic acid production using <Emphasis Type="Italic">Streptomyces lividans</Emphasis> expressing phenylalanine ammonia lyase

Cinnamic acid production was demonstrated using Streptomyces as a host. A gene encoding phenylalanine ammonia lyase (PAL) from Streptomyces maritimus was introduced into Streptomyces lividans, and its expression was confirmed by Western blot analysis. After 4 days cultivation using glucose as carbon source, the maximal level of cinnamic acid reached 210 mg/L. When glycerol (30 g/L) was used as carbon source, the maximal level of produced cinnamic acid reached 450 mg/L. In addition, using raw starch, xylose or xylan as carbon source, the maximal level of cinnamic acid reached 460, 300, and 130 mg/L, respectively. We demonstrated that S. lividans has great potential to produce cinnamic acid as well as other aromatic compounds.     

Exercise-induced left bundle branch block and subsequent mechanical left ventricular dyssynchrony--resolved with pharmacological therapy

A 53-year-old man with depressed ejection fraction (EF) of 35% and QRS width of 88 ms at rest was admitted to our institution with a complaint of exertional chest discomfort and dyspnea. During treadmill exercise, left bundle-branch block (LBBB) with a QRS width of 152 ms occurred at a heart rate of 100 bpm. During LBBB, the patient showed significant mechanical dyssynchrony as evidenced by a two-dimensional speckle tracking radial strain of 260 ms (≥ 130 ms), defined as the time difference between anterior-septum and posterior wall. Five-month after carvedilol and candesartan administration, EF had improved to 49% and LBBB did not occur until a heart rate of 126 bpm was attained during treadmill exercise. It appears that pharmacological therapy may be useful for patients with heart failure and exercise-induced LBBB.     

Risk factors for severe outcomes following 2009 influenza A (H1N1) infection: a global pooled analysis

Background

Since the start of the 2009 influenza A pandemic (H1N1pdm), the World Health Organization and its member states have gathered information to characterize the clinical severity of H1N1pdm infection and to assist policy makers to determine risk groups for targeted control measures.

Methods and Findings

Data were collected on approximately 70,000 laboratory-confirmed hospitalized H1N1pdm patients, 9,700 patients admitted to intensive care units (ICUs), and 2,500 deaths reported between 1 April 2009 and 1 January 2010 from 19 countries or administrative regions—Argentina, Australia, Canada, Chile, China, France, Germany, Hong Kong SAR, Japan, Madagascar, Mexico, the Netherlands, New Zealand, Singapore, South Africa, Spain, Thailand, the United States, and the United Kingdom—to characterize and compare the distribution of risk factors among H1N1pdm patients at three levels of severity: hospitalizations, ICU admissions, and deaths. The median age of patients increased with severity of disease. The highest per capita risk of hospitalization was among patients <5 y and 5–14 y (relative risk [RR] = 3.3 and 3.2, respectively, compared to the general population), whereas the highest risk of death per capita was in the age groups 50–64 y and ≥65 y (RR = 1.5 and 1.6, respectively, compared to the general population). Similarly, the ratio of H1N1pdm deaths to hospitalizations increased with age and was the highest in the ≥65-y-old age group, indicating that while infection rates have been observed to be very low in the oldest age group, risk of death in those over the age of 64 y who became infected was higher than in younger groups. The proportion of H1N1pdm patients with one or more reported chronic conditions increased with severity (median = 31.1%, 52.3%, and 61.8% of hospitalized, ICU-admitted, and fatal H1N1pdm cases, respectively). With the exception of the risk factors asthma, pregnancy, and obesity, the proportion of patients with each risk factor increased with severity level. For all levels of severity, pregnant women in their third trimester consistently accounted for the majority of the total of pregnant women. Our findings suggest that morbid obesity might be a risk factor for ICU admission and fatal outcome (RR = 36.3).

Conclusions

Our results demonstrate that risk factors for severe H1N1pdm infection are similar to those for seasonal influenza, with some notable differences, such as younger age groups and obesity, and reinforce the need to identify and protect groups at highest risk of severe outcomes. Please see later in the article for the Editors'' Summary     

The genetic status of two subspecies of Rhodeus atremius, an endangered bitterling in Japan

Rhodeus atremius is an endemic bitterling fish from Japan comprising two endangered subspecies, R. a. atremius and R. a. suigensis. The latter subspecies, which had dramatically declined in last decades, was reported to contain two distinct mtDNA lineages. In order to estimate the optimized units for conservation management, the genetic structure of R. atremius was inferred by analyzing mtDNA and microsatellite markers (MS). Allelic richness and heterozygosity of MS in R. a. suigensis was less than half that in R. a. atremius. In R. a. suigensis, not only within-population genetic diversity but also among-population genetic divergence was low, with the exception of population Ah1, while the diversity was high and the divergence showed isolation by distance in R. a. atremius. In mtDNA and MS, R. a. suigensis concordantly formed a single lineage, while R. a. atremius encompassed four mtDNA lineages, two of which were completely admixed into one group on the basis of MS. In population Ah1 a striking introgression between the two subspecies was suggested by a Bayesian-based assignment test, with the presence of mtDNA haplotype of R. a. atremius. Contrary to the prevailing theory, R. a. suigensis corresponds to a single conservation unit, while three units seem appropriate for R. a. atremius. In addition, low genetic diversity of R. a. suigensis might have arisen mainly as a result of recent bottlenecks before population fragmentation, followed by current anthropogenic effects. Genetic introgression in population Ah1 was probably the result of human transplantation of R. a. atremius.     

Indirect effects of excessive deer browsing through understory vegetation on stream insect assemblages

Over the past decade, the abundance of sika deer has rapidly increased around Japan. Previous studies have showed overabundance of deer causes drastic reduction of forest understory vegetation, leading excessive soil erosion. However, no study has investigated the effects of excessive deer browsing on aquatic insect assemblages via sediment runoff. These effects are important to understand whether the terrestrial alteration by deer influences aquatic ecosystems. In a primary deciduous forest catchment in Ashiu, Kyoto, a deer exclusion fence has been in place since 2006. We compared forest floor cover, overland flow, stream environment, and aquatic insect assemblages in first-order streams and catchments inside and outside of the deer-exclosure from May-2008 to April-2009. The floor inside the deer-exclosure catchment was covered by lush understory vegetation, whereas outside was almost bare. The overland flow runoff rate at midslope and the dominancy of fine sediment deposition in the streambed were higher outside than inside. Among aquatic insects, burrowers, which are tolerant against fine sediment deposition, were significantly more abundant outside than inside, whereas clingers exhibited the opposite patterns. Collector-gatherers, which feed on fine detritus, were significantly more abundant outside than inside. Meanwhile, filterers were more abundant inside. The Simpson’s diversity index of the aquatic insect assemblages was higher inside than outside. These results suggest that the demise of understory vegetation due to excessive deer browsing has indirectly caused changes in the aquatic insect assemblages of this catchment via increased sediment runoff and subsequent sandy sedimentation of the streambed.     

Intralocus sexual conflict and offspring sex ratio

Males and females frequently have different fitness optima for shared traits, and as a result, genotypes that are high fitness as males are low fitness as females, and vice versa. When this occurs, biasing of offspring sex-ratio to reduce the production of the lower-fitness sex would be advantageous, so that for example, broods produced by high-fitness females should contain fewer sons. We tested for offspring sex-ratio biasing consistent with these predictions in broad-horned flour beetles. We found that in both wild-type beetles and populations subject to artificial selection for high- and low-fitness males, offspring sex ratios were biased in the predicted direction: low-fitness females produced an excess of sons, whereas high-fitness females produced an excess of daughters. Thus, these beetles are able to adaptively bias sex ratio and recoup indirect fitness benefits of mate choice.     

Expression of TRPV1 Channels after Nerve Injury Provides an Essential Delivery Tool for Neuropathic Pain Attenuation

Increased expression of the transient receptor potential vanilloid 1 (TRPV1) channels, following nerve injury, may facilitate the entry of QX-314 into nociceptive neurons in order to achieve effective and selective pain relief. In this study we hypothesized that the level of QX-314/capsaicin (QX-CAP) - induced blockade of nocifensive behavior could be used as an indirect in-vivo measurement of functional expression of TRPV1 channels. We used the QX-CAP combination to monitor the functional expression of TRPV1 in regenerated neurons after inferior alveolar nerve (IAN) transection in rats. We evaluated the effect of this combination on pain threshold at different time points after IAN transection by analyzing the escape thresholds to mechanical stimulation of lateral mental skin. At 2 weeks after IAN transection, there was no QX-CAP mediated block of mechanical hyperalgesia, implying that there was no functional expression of TRPV1 channels. These results were confirmed immunohistochemically by staining of regenerated trigeminal ganglion (TG) neurons. This suggests that TRPV1 channel expression is an essential necessity for the QX-CAP mediated blockade. Furthermore, we show that 3 and 4 weeks after IAN transection, application of QX-CAP produced a gradual increase in escape threshold, which paralleled the increased levels of TRPV1 channels that were detected in regenerated TG neurons. Immunohistochemical analysis also revealed that non-myelinated neurons regenerated slowly compared to myelinated neurons following IAN transection. We also show that TRPV1 expression shifted towards myelinated neurons. Our findings suggest that nerve injury modulates the TRPV1 expression pattern in regenerated neurons and that the effectiveness of QX-CAP induced blockade depends on the availability of functional TRPV1 receptors in regenerated neurons. The results of this study also suggest that the QX-CAP based approach can be used as a new behavioral tool to detect dynamic changes in TRPV1 expression, in various pathological conditions.     

Not an ancient relic: the endemic Livistona palms of arid central Australia could have been introduced by humans

Livistona mariae is an endemic palm localized in arid central Australia. This species is separated by about 1000 km from its congener L. rigida, which grows distantly in the Roper River and Nicholson-Gregory River catchments in northern Australia. Such an isolated distribution of L. mariae has been assumed to have resulted from contraction of ancestral populations as Australia aridified from the Mid-Miocene (ca 15 Ma). To test this hypothesis at the population level, we examined the genetic relationships among 14 populations of L. mariae and L. rigida using eight nuclear microsatellite loci. Our population tree and Bayesian clustering revealed that these populations comprised two genetically distinct groups that did not correspond to the current classification at species rank, and L. mariae showed closest affinity with L. rigida from Roper River. Furthermore, coalescent divergence-time estimations suggested that the disjunction between the northern populations (within L. rigida) could have originated by intermittent colonization along an ancient river that has been drowned repeatedly by marine transgression. During that time, L. mariae populations could have been established by opportunistic immigrants from Roper River about 15 000 years ago, concurrently with the settlement of indigenous Australians in central Australia, who are thus plausible vectors. Thus, our results rule out the ancient relic hypothesis for the origin of L. mariae.