Reproductive biology of racer goby Neogobius gymnotrachelus in the Włocławski Reservoir (Vistula River, Poland)

Initial studies on the reproductive parameters and spawning behaviour of racer goby Neogobius gymnotrachelus, one of three Ponto‐Caspian gobiid species recently invading Polish waters, were carried out in W?oc?awski Reservoir (lower River Vistula, Poland), where spawning lasted from April to August. Males were on average about 23.3% longer and 53.8% heavier than females. The smallest female with mature gonads was 58 mm TL (estimated age 2+ years), and males were sexually mature at 59 mm TL (age of 1+ years). Gonado‐somatic index at the beginning of spawning was seven times larger in females (mean = 8.4) than that in males (mean = 1.2). Mean absolute fecundity was 952 eggs per female (361–2236). Egg diameter ranged from 0.140 to 1.558 mm, being of bi‐modal distribution, which suggests two or three spawning bouts. Length–frequency analysis of juveniles revealed a multimodal distribution. Specialized reproductive behaviour (nest construction and parental care of eggs) and an extended spawning period increase the probability that racer goby can successfully establish self‐sustaining populations in novel environments.     

Effects of IPO-63, Carbaryl, Foschlor and Reglone on Newcastle disease virus replication in chick embryo and chick embryo cell cultures

Cell cultures and chicken embryos were treated with maximum tolerant concentrations of different compounds and infected with Newcastle disease virus simultaneously or 24 hours after the compounds were introduced. The similar results were obtained in both cases. It was found that Reglone inhibited Carbaryl increased virus multiplication. The study on dynamics of virus multiplication indicates that only in the case of IPO and Carbaryl their stimulatory effect on virus at the final stage was preceded by its inhibition.     

Gene mapping of 28S rDNA sites in allotriploid Cobitis females (Pisces: Cobitidae) from a diploid-polyploid population

We performed cytogenetic analysis on triploid Cobitis hybrid specimens from a natural diploid-polyploid population in the Bug River (Poland). Chromosomes were examined by fluorescence in situ hybridization method (FISH) with 28S rDNA as a probe. The rDNA sites were commonly identified in the terminal position of p arms of two small submetacentric chromosomes, in the centromere area of two acrocentric chromosomes and in the terminal position of q arm of one acrocentric chromosome. Some of the observed signals were stronger than others. In few cases, one small acrocentric chromosome showing rDNA sites located terminally on both p and a q arm was observed. This study brings useful information about polymorphism of 28S rDNA sites regarding their number, location and size in triploid specimens. Moreover, it gives preliminary data for comparison with similar researches on the parental species of Cobitis hybrid females, viz. C. taenia, C. taurica and C. tanaitica, and other related Cobitis taxa of different ploidy level. The present study increases our knowledge about ribosomal genes inheritance between Cobitis species and their polyploid hybrids.     

An NAD+ Phosphorylase Toxin Triggers Mycobacterium tuberculosis Cell Death

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Differential responsiveness to immunoablative therapy in refractory rheumatoid arthritis is associated with level and avidity of anti-cyclic citrullinated protein autoantibodies: a case study

In order to identify pathogenic correlates of refractory rheumatoid arthritis (RA), antibodies against anti-cyclic citrullinated protein (ACPAs) were investigated in RA patients in whom the dysregulated immune system had been ablated by high-dose chemotherapy (HDC) and autologous haematopoietic stem cell transplantation (HSCT). Six patients with refractory RA were extensively characterized in terms of levels of total immunoglobulins, RA-specific autoantibodies (ACPAs and rheumatoid factor) and antibodies against rubella, tetanus toxoid (TT) and phosphorylcholine before and after HDC plus HSCT. Additionally, the avidity of ACPAs was measured before and after treatment and compared with the avidity of TT antibodies following repeated immunizations. Synovial biopsies were obtained by arthroscopy before HDC plus HSCT, and analyzed by immunohistochemistry. In the three patients with clinically long-lasting responses to HDC plus HSCT (median 423 days), significant reductions in ACPA-IgG levels after therapy were observed (median level dropped from 215 to 34 arbitrary units/ml; P = 0.05). In contrast, stable ACPA-IgG levels were observed in three patients who relapsed shortly after HDC plus HSCT (median of 67 days). Clinical responders had ACPA-IgG of lower avidity (r = 0.75; P = 0.08) and higher degree of inflammation histologically (r = 0.73; P = 0.09). Relapse (after 38 to 530 days) in all patients was preceded by rising levels of low avidity ACPA-IgG (after 30 to 388 days), in contrast to the stable titres of high avidity TT antibodies. In conclusion, humoral autoimmune responses were differentially modulated by immunoablative therapy in patients with synovial inflammation and low avidity ACPA-IgG autoantibodies as compared with patients with high levels of high avidity ACPA-IgG. The distinct clinical disease course after immunoablative therapy based on levels and avidity of ACPA-IgG indicates that refractory RA is not a single disease entity.     

Mouse gastrocnemius muscle regeneration after mechanical or cardiotoxin injury

The goal of our study was to compare the skeletal muscle regeneration induced by two types of injury: either crushing, that causes muscle degeneration as a result of mechanical devastation of myofibers, or the injection of a cardiotoxin that is a myotoxic agent causing myolysis of myofibers leading to muscle degeneration. Regenerating muscles were analyzed at selected intervals, until the 14th day following the injury. We analyzed their weight and morphology. We also studied the expression of different myosin heavy chain isoforms as a molecular marker of the regeneration progress. Histological analysis revealed that inflammatory response and myotube formation in crushed muscles was delayed compared to cardiotoxin-injected ones. Moreover, the expression of myosin heavy chain isoforms was observed earlier in cardiotoxin-injured versus crushed muscles. We conclude that the dynamics of skeletal muscle regeneration depends on the method of injury.     

Transitional cell carcinoma of the ovary: A rare case and review of literature

Goblet cell carcinoid of the large intestine is a rare neoplasm, usually located in ascending colon and rectum. A 60-year-old male patient underwent surgery after the diagnosis of acute abdomen. Exploratory laparotomy revealed perforation with a diameter of 1 cm at the site of the previously performed gastroenterostomy and dilatation of the right colic flexure, secondary to a solid obstructive mass located in the mid-portion of transverse colon. Histopathological investigation of the biopsies, taken from the gastroenterostomy site and the tumor, revealed mixed carcinoid-adenocarcinoma with carcinoid component, predominantly composed of goblet cells. Three cycles of FOLFOX-4 protocol was administered. Following respiratory distress secondary to pulmonary metastasis, the patient's condition deteriorated and subsequently died in the fourth postoperative month. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm.     

Prospective cohort studies on risk factors for cardiovascular events in systemic lupus erythematosus: a major challenge

Cardiovascular disease (CVD) has been identified as a major contributor to morbidity and mortality in patients with systemic lupus erythematosus (SLE). The etiology of premature CVD in SLE is supposed to have many factors, including traditional coronary artery disease (CAD) risk factors, antiphospholipid antibodies, and metabolic and inflammatory factors. Despite the overwhelming interest in CVD in SLE research, prospective studies evaluating risk factors for hard endpoints (that is, cardiovascular events) are relatively scarce. The article by Gustafsson and colleagues suggests that prothrombotic factors play an important role in SLE-related CVD and that the influence of traditional CAD risk factors might be limited.     

Syndecan-4 distribution during the differentiation of satellite cells isolated from soleus muscle treated by phorbol ester and calphostin C

It was shown that syndecans have a potential role in muscle development. We focused this study on the role of syndecan-4 distribution and phosphorylation during the differentiation of satellite cells isolated from Soleus muscle. Syndecans are cell surface heparan sulfate proteoglycans (HSPGs) that bind numerous ligands through their HS glycosaminoglycan chains (GAG). They play a role in cell-extracellular matrix and cell-cell adhesion, signal transduction and the targeting of growth factors and other molecules to the cell surface. Syndecan-4 acts as a co-receptor or, along with integrins, is localized to the cell membrane of focal contacts. Syndecan-4 participates in the organization of the structure of focal contacts reacting with extracellular matrix molecules. The interaction of syndecan-4 with protein kinase C (PKC) isoforms is the main mechanism regulating its distribution in cells. Our current study focused on the role of the distribution of syndecan-4, and its interactions with PKC isoforms during the differentiation of activated satellite cells. We used the PKC activator TPA (12-O-tetradecanoyl phorbol 13-acetate) and the PKC inhibitor Calphostin C (Cal C). We concluded that syndecan-4 was important not only in the activation of satellite cells, but also in myoblast differentiation. During our research, we observed the presence of syndecan-4 and changes in its location over the course of that process. We also showed that TPA and Cal C treatment had an influence on the subcellular distribution of syndecan-4, but there was no influence on myoblast differentiation. We speculated that the reason for changes after TPA treatment was the interactions with activated PKC alpha, which provoked syndecan-4/PKC alpha complex translocation to integrins. We also supposed that Cal C treatment inhibited PKC delta activity and probably induced PKC lpha association to syndecan-4, and syndecan-4 translocation to integrins.