Incidence and outcome of bleeding before the 20th week of pregnancy: prospective study from general practice.

OBJECTIVE: To estimate the miscarriage rate in a cohort of pregnant women and the final outcome of pregnancy. DESIGN: Two year prospective community study. SETTING: Women registered with four semirural practices at one health centre. SUBJECTS: 626 pregnant women from a population 21448, 5140 of whom were women aged 15-44 years. MAIN OUTCOME MEASURES: Vaginal bleeding and outcome of pregnancy. Results: 76 of the 89 women with an unwanted pregnancy requested a termination. In the 550 ongoing pregnancies bleeding occurred before the 20th week in 117 (21%), and 67 (12%) ended in miscarriage. The risk of miscarriage was not significantly increased after a miscarriage in the previous pregnancy (11 (15%) women had miscarriage v 55 (12%) women who had not had miscarriage) who had previously had a live birth). Of the 117 women with bleeding, 64 were not admitted to hospital by the general practitioner; 42 of these women had an ultrasound examination at the health centre and 19 subsequently miscarried at home. In hospital 41 of 46 women who miscarried had evacuation of the uterus. CONCLUSIONS: Bleeding occurred in one fifth of recognised pregnancies before the 20th week and over half of these miscarried. Treatment of women with miscarriage at home means current statistics on miscarriage in Britain are missing many cases.     

Biomass productivity of two <Emphasis Type="Italic">Scenedesmus</Emphasis> strains cultivated semi-continuously in outdoor raceway ponds and flat-panel photobioreactors

Semi-continuous algal cultivation was completed in outdoor flat-panel photobioreactors (panels) and open raceway ponds (raceways) from February 17 to May 7, 2015 for side-by-side comparison of areal productivities at the Arizona Center for Algae Technology and Innovation in Mesa, AZ, USA. Experiments used two strains of Scenedesmus acutus (strains LB 0414 and LB 0424) to assess productivity, areal density, nutrient removal, and harvest volume across cultivation systems and algal strains. Panels showed an average biomass productivity of 19.0?±?0.6 g m^?2 day^?1 compared to 6.62?±?2.3 g m^?2 day^?1 for raceways. Photosynthetic efficiency ranged between 1.32 and 2.24 % for panels and between 0.30 and 0.68 % for raceways. Panels showed an average nitrogen consumption rate of 38.4?±?8.6 mg N L^?1 day^?1. Cultivation in raceways showed a consumption rate of 3.8?±?2.5 and 7.1?±?4.2 mg N L^?1 day^?1 for February/March and April/May, respectively, due to increase in biomass productivity. Excess nutrients were required to prevent a decrease in productivity. Daily biomass harvest volumes between 18 and 36 % from panels did not affect culture productivity, but density decreased with increased harvest volume. High cultivation temperatures above 30 °C caused strain LB 0414 to lyse and crash. Strain LB 0424 did not show any difference in biomass productivity when peak temperatures reached 34, 38, or 42 °C, but showed decreased productivity when the peak temperature during cultivation was 30 °C. Using algal strains with different temperature tolerances can generate increased annual biomass productivity.     

Real-time PCR for detection and quantification,and histological characterization of <Emphasis Type="Italic">Neonectria ditissima</Emphasis> in apple trees

Key message

We designed a pair of primers from a region of the β-tubulin gene to detect and quantify Neonectria ditissima in wood of some infected apple cultivars, and optimized light microscopy to study fungal-plant interactions.

Abstract

Neone ctria ditissima, the causal pathogen of fruit tree canker, is a sordariomycete fungus that affects apple orchards, especially in north-western Europe. To prevent serious disease epidemics, an accurate, rapid, and sensitive method for detection of N. ditissima is needed for pathogen identification. A quantitative real-time PCR (qPCR) assay was developed for both detection and quantification of this pathogen in infected apple cultivars. Several primer sets were designed from regions of the β-tubulin gene. One primer set passed several validation tests, and the melting curve confirmed species-specific amplification of the correct product. In addition, the N. ditissima biomass could be detected at variable amounts in samples from the infection sites of six different cultivars, with ‘Aroma’ having the lowest amount of N. ditissima biomass and ‘Elise’ the highest. To complement the qPCR results, tissue from detached shoots and 1-year-old trees of ‘Cox’s Orange Pippin’ (susceptible) and ‘Santana’ (partially resistant) was used in a histopathology study. In both detached shoots and trees, fungal hyphae were found in cells of all tissues. No qualitative differences in the anatomy of the infected samples were observed between the cultivars. In the detached shoot experiment, both cultivars were affected but differences in the rate of disease progression suggest that the partially resistant cultivar could resist the fungus longer. The qPCR assay developed in our study produced reproducible results and can be used for detection of N. ditissima in infected trees.

     

An integrated linkage map reveals candidate genes underlying adaptive variation in Chinook salmon (Oncorhynchus tshawytscha)

Salmonids are an important cultural and ecological resource exhibiting near worldwide distribution between their native and introduced range. Previous research has generated linkage maps and genomic resources for several species as well as genome assemblies for two species. We first leveraged improvements in mapping and genotyping methods to create a dense linkage map for Chinook salmon Oncorhynchus tshawytscha by assembling family data from different sources. We successfully mapped 14 620 SNP loci including 2336 paralogs in subtelomeric regions. This improved map was then used as a foundation to integrate genomic resources for gene annotation and population genomic analyses. We anchored a total of 286 scaffolds from the Atlantic salmon genome to the linkage map to provide a framework for the placement 11 728 Chinook salmon ESTs. Previously identified thermotolerance QTL were found to colocalize with several candidate genes including HSP70, a gene known to be involved in thermal response, as well as its inhibitor. Multiple regions of the genome with elevated divergence between populations were also identified, and annotation of ESTs in these regions identified candidate genes for fitness related traits such as stress response, growth and behaviour. Collectively, these results demonstrate the utility of combining genomic resources with linkage maps to enhance evolutionary inferences.     

Dermatophytosis of the scalp: Incidence,immune response,and epidemiology

Tinea capitis remains a common infection among the pediatric population of North America. The gray patch Microsporum audouinii infections of the 1950's have been supplanted by the black dot ringworm of Trichophyton tonsurans. The clinical presentation of T. tonsurans infection is quite variable and may be related to specific host T-lymphocyte response. This dermatophytosis is most frequently incurred from contact with an infected child either directly or via a variety of fomites. Current studies indicate that an asymptomatic adult carrier state may also exist which could contribute to the morbidity of this mycosis.Part of a DissertationPresented as a part of the Everett S. Beneke Symposium in Mycology, May 27, 1988.     

The role of phosphotungstic and phosphomolybdic acids in connective tissue staining I. Histochemical studies

Synopsis An investigation of the role of phosphotungstic and phosphomolybdic acids in Mallory-like trichrome methods showed unexpectedly that, rather than acting as mordants to anionic dyes, these polyacids selectively blocked staining of all tissue components other than connective tissue fibres to Aniline Blue and other similar fibrereactive dyes. Connective tissue components were found to contain residues resembling histidine that are easily accessible to anionic dyes. Blocking towards typical anionic dyes for demonstrating plasma proteins, such as Biebrich Scarlet, was also demonstrated but was less complete. The blockade of both types of dye was labile if the staining times were extended; plasma dyes were more sensitive than fibre dyes in this respect. Histochemical reactions for tyrosine residues were blocked. In connective tissue, phosphotungstic acid did not block histidine residues demonstrable by the coupled tetrazonium reaction with previous iodination. Thus it is postulated that differential trichrome staining occurs by binding of Aniline Blue to basic residues in the connective tissue not blocked by phosphotungstic acid and subsequent replacement of the blocking agent by an anionic dye. The binding of phosphotungstic acid to both epithelium and connective tissue was demonstrated by the quenching of autofluorescence in these regions and by the reduction of the bound PTA to blue coloured products with titanium trichloride.     

Specific versus nonspecific target cell destruction by T lymphocytes sensitized in vitro. II. Responsible factors for nonspecific destruction

Cell-free supernatants of thoracic duct lymphocyte cultures which were stimulated in vitro by horse serum on syngeneic fibroblast monolayers are demonstrated to be cytotoxic on syngeneic embryonic fibroblasts by means of a direct cell count using microtest plates. Experimental supernatants showed up to 100% suppression of fibroblast growth at $\text{1}\text{3}$ dilution and up to 96% suppression at $\text{1}\text{4}$ dilution as compared to the control supernatants. Evidence is presented indicating that lymphocytes cultured on mosaic monolayers, which were comprised of syngeneic and xenogeneic fibroblasts, were reacting both to xenogeneic cells and horse serum in the medium at the cellular level. A hapten-to-carrier type relationship is suggested between xenogeneic antigen and horse serum. Absence of horse serum in the test cultures using these lymphocytes resulted in the abrogation of nonspecific toxic activity of lymphocytes while the specific activity, though diminished, remained. This again indicates the difference in the mechanisms underlying the specific and nonspecific target cell destruction by T cells.     

Effect of Sodium Fluorescein and Plating Medium on Recovery of Irradiated Escherichia coli and Serratia marcescens from Aerosols

Irradiation of aerosols of either Escherichia coli or Serratia marcescens with simulated solar (xenon) radiation caused a significant decrease in viability. When sodium fluorescein was employed to determine the physical loss of organisms from the aerosol, an additional adverse effect upon survival was noted. The decay curves indicated that at least two mechanisms of inactivation were operative, one due to aerosolization, the other to irradiation. After collection from aerosols, both species of microorganisms grew better on blood agar base than on Casitone agar, but this finding did not appear to be related to the effect of irradiation.     

A CYTOLOGICAL STUDY OF THE RELATION OF THE CORTICAL REACTION TO SUBSEQUENT EVENTS OF FERTILIZATION IN URETHANE-TREATED EGGS OF THE SEA URCHIN, ARBACIA PUNCTULATA

Eggs of the sea urchin, Arbacia punctulata, treated with 3% urethane for 30 sec followed by 0.3% urethane and inseminated are polyspermic and fail to undergo a typical cortical reaction. Upon insemination the vitelline layer of urethane-treated eggs either does not separate or is raised only a short distance from the oolemma. 1–6 min after insemination, almost all of the cortical granules remain intact and are dislodged from the plasmalemma. Later (6 min to the two-cell stage) some cortical granules are released randomly along the surface of the zygote. Not all zygotes show the same degree of cortical granule dehiscence; most of them experience little if any granule release whereas others demonstrate considerably more. The thickness of the hyaline layer appears to be directly related to the number of cortical granules released. Subsequent to pronuclear migration, several male pronuclei become associated with the female pronucleus. Later the male and female pronuclear envelopes contact and the outer and the inner laminae fuse, thereby forming the zygote nucleus. The male pronuclei remaining in the cytoplasm increase in size and progressively migrate to, and fuse with, the zygote nucleus. By 60 min some zygotes appear to contain only one large zygote nucleus which subsequently enters mitosis. Other zygotes possess a number of male pronuclei which remain unfused, and later these pronuclei along with the zygote nucleus undergo mitosis. There does not appear to be a direct relation between the number of cortical granules a zygote possesses and the above mentioned dichotomy.     

A CYTOLOGICAL STUDY OF ARTIFICIAL PARTHENOGENESIS IN THE SEA URCHIN ARBACIA PUNCTULATA

Eggs of the sea urchin Arbacia punctulata were artificially activated with hypertonic seawater. The artificially activated eggs undergo the cortical reaction which is not distinguished by a wavelike progression as in the case of inseminated eggs. The cortical granules are released at random loci at the surface of the egg and result in spaces separated by large cytoplasmic projections. Unreacted cortical granules and ribosomes are found within the matrix comprising the large cytoplasmic projections. No "fertilization cone" is formed. The subsequent release of additional cortical granules results in the formation of a continuous perivitelline space, 15 min following activation. 85 min postactivation, an organization of annulate lamellae, endoplasmic reticulum of the smooth variety, and microtubules around a centriole is observed prior to nuclear division. Before the breakdown of the nuclear envelope a streak stage is formed. The streak is composed of a central core of annulate lamellae and is encompassed by endoplasmic reticulum and vesicular components. Condensation of chromatin is followed by the establishment of the mitotic apparatus. Centrioles were not found in the mature egg; however, they are present after activation prior to the first nuclear division, in the four-cell embryo, multicellular embryo, and at blastula. Artificially activated eggs have been observed to develop to the pluteus stage in more than 50% of the eggs treated.