Composition and ultrastructure of elasmobranch granulocytes. I. Dogfishes (Squaliformes)

The blood granulocyte composition of 10 species of dogfish is given, together with ultrastructural observations made on Etmopterus baxteri Leydig organ and blood, and on spleens of Oxynotus bruniensis, Deania calcea, Scymnodon plunketi and blood of Centroscymnus crepidator . Neutrophilic granulocytes, which were common, had spherical granules that developed a dense core, which then lost contents to become lucent. Eosinophilic granulocytes had ovoid or elongated granules with a fibrillar content that became aligned longitudinally, and rarely formed an axial rod. Eosinophils had large spherical granules that were electron-dense but in early stages had a disorganised fibrillar content. These cells correspond to the neutrophils, heterophils and eosinophils, respectively, of other elasmobranchs.
Dogfish granulocytes are compared with those of other elasmobranchs, and their lack of similarity to those of higher vertebrates is noted.     

Observations on the granulocyte peroxidase of teleosts: a phylogenetic perspective

Observations on granulocyte peroxidase of 123 teleosts are reported and correlated with previous studies to put occurrence of fish granulocyte peroxidase in a phylogenetic perspective. Eosinophil peroxidase occurs in archaic groups such as lungfish and sturgeons, but is usually weak and infrequently observed in chondrichthyans, and in teleosts occurs in some elopomorphs, is consistently observed in stomiiforms, is rarely observed and usually weak in acanthopterygians and absent from salmoniforms, scopelomorphs and paracanthopterygians. Peroxidase is absent from lungfish and sturgeon neutrophils, is present in neutrophils of some elopomorphs and clupeimorphs. both of which are basal teleost groups, but in salmoniforms and higher teleosts is consistently observed in neutrophils. although often weak in pleuronectiforms.
Loss of eosinophil peroxidase and development of neutrophil peroxidase in teleosts may be due to inefficient phagocytosis and loss of peroxidase with degranulation in eosinophils, being superseded by concentration of peroxidase in phagosomes in neutrophils.     

Observations on eosinophilic granule cells in peritoneal exudates of eels, Anguilla amtmlis

Eosinophilic granule cells (EGC) are reported among peritoneal exudate cells (PEC) of unstimulated and carrageenan-, zymosan-, latex- and Aeromonas hydrophila -stimulated eels, Anguilla australis . At the light microscopy level EGC are large (< 50 μm diameter) and have strongly to moderately basophilic cytoplasm, eosinophilic granules, and often striated colourless cytoplasmic inclusions. Ultrastructurally, the cytoplasm is rich in ribosomes, and contains characteristic granules, parallel tubular structures 46–50 nm in diameter, and parallel rod-like arrays (PRLA) 14–15 nm in diameter that are angular or hexagonal in cross section. EGC contain granule-associated, partially or completely cyanide inhibited, but azide and aminotriazole resistant, peroxidase, acid phosphatase, esterases and weak cytoplasmic periodic acid-Schiff positivity. PRLA lack enzyme content. A few (< 10%) unstimulated and carrageenan- and zymosan-stimulated EGC contain granule-associated and diffuse β-galactosidase, and EGC in eels injected i.p. with filtered carrageenan-stimulated PEC supernatants show heterogeneity in glucosaminidase content.     

The effects of 3,5-diiodo-4-hydroxybenzoic acid on the oxidation of IAA and auxin-induced ethylene production by cress root segments

Summary In previous research here, 3,5-diiodo-4-hydroxybenzoic acid (DIHB) was shown to promote the elongation of roots of cress (Lepidium sativum) seedlings growing in light, and to inhibit the auxin-induced production of ethylene in this tissue. Although DIHB is a cofactor for the oxidation of indole-3-acetic acid (IAA) by horse-radish peroxidase, it inhibits the decarboxylation of [1-¹⁴C]IAA by segments excised from cress roots. The inhibition by DIHB of ethylene production by this tissue does not, therefore, arise from a reduction of IAA levels. These findings are discussed in relation to the effects of DIHB on cress root growth.Abbreviations IAA indole-3-acetic acid - DIHB 3,5-diiodo-4-hydroxybenzoic acid - DCP 2,4-dichlorophenol - 2,4-D 2,4-dichlorophenoxyacetic acid This study forms part of a research project to be submitted by M.L.R. for PhD degree and supported by a grant from Consejo Nacional de Ciencia y Tecnología (México).     

Ethylene production by cress roots and excised cress root segments and its inhibition by 3,5-diiodo-4-hydroxybenzoic acid

Summary 3,5-Diiodo-4-hydroxybenzoic acid (DIHB) has been shown to exert an inhibitory effect on the formation of ethylene by the roots of intact cress Lepidium sativum seedlings in light, and by excised cress root segments. Adding IAA to the culture solution greatly promoted ethylene production, which was suppressed by DIHB. The findings together with results obtained with dinitrophenol (DNP), L-methionine and L-ethionine and also the horseradish peroxidase/methional system of Yang are discussed.The results indicate that the effect of DIHB in promoting the root growth of cress seedlings in nutrient solution in the light operates, at least in part, by suppressing the formation of the root growth inhibitor ethylene.Abbreviation GLC gas-liquid chromatography - dIHB 3,5-diiodo-4-hydroxybenzoic acid This study forms part of research to be submitted for PhD degree and supported by a grant from Consejo Nacional de Ciencia y Tecnología (México).     

Breast MRI in nonpalpable breast lesions: a randomized trial with diagnostic and therapeutic outcome – MONET – study

Background

In orthodontic treatment, anchorage control is a fundamental aspect. Usually conventional mechanism for orthodontic anchorage control can be either extraoral or intraoral that is headgear or intermaxillary elastics. Their use are combined with various side effects such as tipping of occlusal plane or undesirable movements of teeth. Especially in cases, where key-teeth are missing, conventional anchorage defined as tooth-borne anchorage will meet limitations. Therefore, the use of endosseous implants for anchorage purposes are increasingly used to achieve positional stability and maximum anchorage.

Methods/Design

The intended study is designed as a prospective, multicenter randomized controlled trial (RCT), comparing and contrasting the effect of early loading of palatal implant therapy versus implant loading after 12 weeks post implantation using the new ortho-implant type II anchor system device (Orthosystem Straumann, Basel, Switzerland). 124 participants, mainly adult males or females, whose diagnoses require temporary stationary implant-based anchorage treatment will be randomized 1:1 to one of two treatment groups: group 1 will receive a loading of implant standard therapy after a healing period of 12 week (gold standard), whereas group 2 will receive an early loading of orthodontic implants within 1 week after implant insertion. Participants will be at least followed for 12 months after implant placement. The primary endpoint is to investigate the behavior of early loaded palatal implants in order to find out if shorter healing periods might be justified to accelerate active orthodontic treatment. Secondary outcomes will focus e.g. on achievement of orthodontic treatment goals and quantity of direct implant-bone interface of removed bone specimens. As tertiary objective, a histologic and microtomography evaluation of all retrieved implants will be performed to obtain data on the performance of the SLA surface in human bone evaluation of all retrieved implants. Additionally, resonance frequency analysis (RFA, Osstell? mentor) will be used at different times for clinically monitoring the implant stability and for histological comparison in order to measure the reliability of the resonance frequency measuring device.

Trial registration

Current Controlled Trials ISRCTN97142521.     

Amyloid fibril formation by a helical cytochrome

The substitution of alanines for the two cysteines which form thioether linkages to the haem group in cytochrome c(552) from Hydogenobacter thermophilus destabilises the native protein fold. The holo form of this variant slowly converts into a partially folded apo state that over prolonged periods of time aggregates into fibrillar structures. Characterisation of these structures by electron microscopy and thioflavin-T binding assays shows that they are amyloid fibrils. The data demonstrate that when the native state of this cytochrome is destabilised by loss of haem, even this highly alpha-helical protein can form beta-sheet structures of the type most commonly associated with protein deposition diseases.     

Effects of climate on incidence of Campylobacter spp. in humans and prevalence in broiler flocks in Denmark

Campylobacter infections are increasing and pose a serious public health problem in Denmark. Infections in humans and broiler flocks show similar seasonality, suggesting that climate may play a role in infection. We examined the effects of temperature, precipitation, relative humidity, and hours of sunlight on Campylobacter incidence in humans and broiler flocks by using lag dependence functions, locally fitted linear models, and cross validation methods. For humans, the best model included average temperature and sunlight 4 weeks prior to infection; the maximum temperature lagged at 4 weeks was the best single predictor. For broilers, the average and maximum temperatures 3 weeks prior to slaughter gave the best estimate; the average temperature lagged at 3 weeks was the best single predictor. The combined effects of temperature and sunlight or the combined effects of temperature and relative humidity predicted the incidence in humans equally well. For broiler flock incidence these factors explained considerably less. Future research should focus on elements within the broiler environment that may be affected by climate, as well as the interaction of microclimatic factors on and around broiler farms. There is a need to quantify the contribution of broilers as a source of campylobacteriosis in humans and to further examine the effect of temperature on human incidence after this contribution is accounted for. Investigations should be conducted into food consumption and preparation practices and poultry sales that may vary by season.     

Composition,acquisition, and distribution of the Vi exopolysaccharide-encoding Salmonella enterica pathogenicity island SPI-7

Vi capsular polysaccharide production is encoded by the viaB locus, which has a limited distribution in Salmonella enterica serovars. In S. enterica serovar Typhi, viaB is encoded on a 134-kb pathogenicity island known as SPI-7 that is located between partially duplicated tRNA(pheU) sites. Functional and bioinformatic analysis suggests that SPI-7 has a mosaic structure and may have evolved as a consequence of several independent insertion events. Analysis of viaB-associated DNA in Vi-positive S. enterica serovar Paratyphi C and S. enterica serovar Dublin isolates revealed the presence of similar SPI-7 islands. In S. enterica serovars Paratyphi C and Dublin, the SopE bacteriophage and a 15-kb fragment adjacent to the intact tRNA(pheU) site were absent. In S. enterica serovar Paratyphi C only, a region encoding a type IV pilus involved in the adherence of S. enterica serovar Typhi to host cells was missing. The remainder of the SPI-7 islands investigated exhibited over 99% DNA sequence identity in the three serovars. Of 30 other Salmonella serovars examined, 24 contained no insertions at the equivalent tRNA(pheU) site, 2 had a 3.7-kb insertion, and 4 showed sequence variation at the tRNA(pheU)-phoN junction, which was not analyzed further. Sequence analysis of the SPI-7 region from S. enterica serovar Typhi strain CT18 revealed significant synteny with clusters of genes from a variety of saprophytic bacteria and phytobacteria, including Pseudomonas aeruginosa and Xanthomonas axonopodis pv. citri. This analysis suggested that SPI-7 may be a mobile element, such as a conjugative transposon or an integrated plasmid remnant.     

Successful immunotherapy with matrix metalloproteinase-derived peptides in adjuvant arthritis depends on the timing of peptide administration

We have recently found that matrix metalloproteinases (MMPs) are targets for T-cell and B-cell reactivity in experimental arthritis. In the present article, we investigate whether modulation of MMP-specific T-cell responses could influence the course of adjuvant arthritis (AA). Lewis rats were treated nasally with MMP peptides prior to or after AA induction. Administration of the MMP-10 or the MMP-16 peptide prior to AA induction reduced the arthritic symptoms. In contrast, administration of the MMP-10 peptide after AA induction aggravated the arthritic symptoms. The present study shows the possible usefulness of MMP peptides for immunotherapy. However, a clear understanding of proper timing of peptide administration is crucial for the development of such therapies.