Severe Inbreeding and Small Effective Number of Breeders in a Formerly Abundant Marine Fish

In contrast to freshwater fish it is presumed that marine fish are unlikely to spawn with close relatives due to the dilution effect of large breeding populations and their propensity for movement and reproductive mixing. Inbreeding is therefore not typically a focal concern of marine fish management. We measured the effective number of breeders in 6 New York estuaries for winter flounder (Pseudopleuronectes americanus), a formerly abundant fish, using 11 microsatellite markers (6–56 alleles per locus). The effective number of breeders for 1–2 years was remarkably small, with point estimates ranging from 65–289 individuals. Excess homozygosity was detected at 10 loci in all bays (F_IS = 0.169–0.283) and individuals exhibited high average internal relatedness (IR; mean = 0.226). These both indicate that inbreeding is very common in all bays, after testing for and ruling out alternative explanations such as technical and sampling artifacts. This study demonstrates that even historically common marine fish can be prone to inbreeding, a factor that should be considered in fisheries management and conservation plans.     

Trace element balance is changed in infected organs during acute <Emphasis Type="Italic">Chlamydophila pneumoniae</Emphasis> infection in mice

Most infectious diseases are accompanied by changed levels of several trace elements in the blood. However, sequential changes in trace elements in tissues harbouring bacterial infections have not been studied. In the present study the respiratory pathogen Chlamydophila pneumoniae (C. pneumoniae), adapted to C57BL/6J mice, was used to study whether the balance of trace elements is changed in infected organs. Bacteria were quantitatively measured by real-time PCR in the blood, lungs, liver, aorta, and heart on days 2, 5, and 8 of the infection. Concentrations of 13 trace elements were measured in the liver, heart, and serum by inductively coupled plasma mass-spectrometry (ICP-MS). Infected mice developed expected clinical signs of disease and bacteria were found in lungs, liver, and heart on all days. The number of bacteria peaked on day 2 in the heart and on day 5 in the liver. The copper/zinc (Cu/Zn) ratio in serum increased as a response to the infection. Cu increased in the liver but did not change in the heart. Iron (Fe) in serum decreased progressively, whereas in the heart it tended to increase, and in the liver it progressively increased. C. pneumoniae may thus cause a changed trace element balance in target tissues of infection that may be pivotal for bacterial growth.     

A Dutch guideline for the treatment of scoliosis in neuromuscular disorders

Background

Children with neuromuscular disorders with a progressive muscle weakness such as Duchenne Muscular Dystrophy and Spinal Muscular Atrophy frequently develop a progressive scoliosis. A severe scoliosis compromises respiratory function and makes sitting more difficult. Spinal surgery is considered the primary treatment option for correcting severe scoliosis in neuromuscular disorders. Surgery in this population requires a multidisciplinary approach, careful planning, dedicated surgical procedures, and specialized after care.

Methods

The guideline is based on scientific evidence and expert opinions. A multidisciplinary working group representing experts from all relevant specialties performed the research. A literature search was conducted to collect scientific evidence in answer to specific questions posed by the working group. Literature was classified according to the level of evidence.

Results

For most aspects of the treatment scientific evidence is scarce and only low level cohort studies were found. Nevertheless, a high degree of consensus was reached about the management of patients with scoliosis in neuromuscular disorders. This was translated into a set of recommendations, which are now officially accepted as a general guideline in the Netherlands.

Conclusion

In order to optimize the treatment for scoliosis in neuromuscular disorders a Dutch guideline has been composed. This evidence-based, multidisciplinary guideline addresses conservative treatment, the preoperative, perioperative, and postoperative care of scoliosis in neuromuscular disorders.     

Selenite or selenomethionine interaction with methylmercury on uptake and toxicity showing a weak selenite protection: studies on cultured K-562 cells

Selenium and methylmercuric chloride (MMC) interactions regarding cellular uptake and selenium protection on MMC toxicity have been studied. Human K-562 cells were pretreated or simultaneously treated with either selenite (5 or 50 μM) or selenomethionine (10 or 50 μM) together with (3.5 or 5 μM) MMC. Cells simultaneously treated with selenite or selenomethionine and 3.5 μM MMC showed a decreased mercury concentration with increased selenium dose especially seen in the selenite combinations. The simultaneous selenite and MMC 3.5 μM combinations showed growth curves with an increasing number of viable cells with increased selenite dose. All combinations with 5 μM MMC were toxic to the cells. Interactions between selenite or selenomethionine and MMC regarding cellular uptake of mercury and selenium were observed and indications of selenite protection against MMC toxicity in human K-562 cells were noticed.     

Conodonts from the Early Triassic microbialite of Guangxi (South China): implications for the definition of the base of the Triassic System

We describe a new Early Triassic (Griesbachian) succession of conodont faunas from a high‐resolution sampling of the basal Early Triassic microbial limestone and the base of the overlying unit at the Wuzhuan section (Nanpanjiang Basin, Guangxi, South China). The microbial limestone records the earliest phase of the Early Triassic biotic recovery after the end‐Permian mass extinction. For the first time, rich conodont faunas are reported from within the microbialite. The faunas from Wuzhuan are largely dominated by anchignathodontids, including several Isarcicella species, which were previously documented only from strata above the microbialite. A total of 14 conodont species assigned to three genera is recorded from the Wuzhuan section. Starting from the base of the microbialite upwards, several species are sequentially added to the conodont assemblage. The alpha diversity peaks at the top of the microbialite. The conodont record in the considered microbialite interval at Wuzhuan is presumably unaffected by local ecological changes. It therefore more likely represents an evolutionary rather than an ecological pattern. We compare the Wuzhuan's conodont record with a well‐supported phylogenetic model and suggest that the sequence of first occurrences at Wuzhuan is the closest to the ‘true’ sequence of evolutionary events that took place during this Griesbachian radiation of anchignathodontids. Based on comparisons with the GSSP section at Meishan, we suggest further that the first occurrence of Hindeodus parvus in Meishan does not correspond to its first appearance datum.     

产β—葡萄糖苷酶真菌诱变菌株快速筛选方法

报道了一种快速筛选产β-葡萄糖管酶真菌诱变菌株的方法。该法利用ρNPG经β-葡萄糖苷酶水解,水解产物ρNP在碱性条件下显色的原理。采用自制的特殊初筛平皿.经一年多的实践应用表明此法具有简便、灵敏、筛子消耗量小、筛选效率高等优点。     

Rapid methods for jugular bleeding of dogs requiring one technician

Two methods were used to collect blood from the jugular vein of dogs. In both techniques, only one technician was required. A rope with a slip knot was placed around the base of the neck to assist in restraint and act as a tourniquet for the vein. The technician used one hand to restrain the dog by the muzzle and position the head. The other hand was used for collecting the sample. One of the methods could be accomplished with the dog in its cage. The bleeding techniques were rapid, requiring approximately 1 minute per dog.     

The four hexamerin genes in the honey bee: structure,molecular evolution and function deduced from expression patterns in queens,workers and drones

Background  

Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens.