Stress-shielding induced bone remodeling in cementless shoulder resurfacing arthroplasty: a finite element analysis and in vivo results

Cementless surface replacement arthroplasty (CSRA) of the shoulder was designed to preserve the individual anatomy and humeral bone stock. A matter of concern in resurfacing implants remains the stress shielding and bone remodeling processes. The bone remodeling processes of two different CSRA fixation designs, conical-crown (Epoca RH) and central-stem (Copeland), were studied by three-dimensional (3-D) finite element analysis (FEA) as well as evaluation of contact radiographs from human CSRA retrievals. FEA included one native humerus model with a normal and one with a reduced bone stock quality. Compressive strains were evaluated before and after virtual CSRA implantation and the results were then compared to the bone remodeling and stress-shielding pattern of eight human CSRA retrievals (Epoca RH n=4 and Copeland n=4). FEA revealed for both bone stock models increased compressive strains at the stem and outer implant rim for both CSRA designs indicating an increased bone formation at those locations. Unloading of the bone was seen for both designs under the central implant shell (conical-crown 50–85%, central-stem 31–93%) indicating high bone resorption. Those effects appeared more pronounced for the reduced than for the normal bone stock model. The assumptions of the FEA were confirmed in the CSRA retrieval analysis which showed bone apposition at the outer implant rim and stems with highly reduced bone stock below the central implant shell. Overall, clear signs of stress shielding were observed for both CSRAs designs in the in vitro FEA and human retrieval analysis. Especially in the central part of both implant designs the bone stock was highly resorbed. The impact of these bone remodeling processes on the clinical outcome as well as long-term stability requires further evaluation.     

Inhalation toxicity of methylisocyanate: assessment of germ cell mutagenicity and reproductive effects in rats.

Adult male Wistar rats were exposed to methylisocyanate (MIC, 3.2 mg/l, single inhalation exposure for 8 min under static condition) or ethyl methanesulphonate (EMS, 150 mg/kg, single ip dose) for the assessment of germ cell mutagenicity and reproductive effects. Sequential matings of treated males with normal females on days 1-7, 8-14 and 15-21 post-exposure did not indicate any induction of dominant lethal mutation (increased frequency of preimplantation losses and early fetal deaths) by MIC but it was significantly induced by EMS as compared to respective controls. Males, necropsied after 21 days of exposure, showed no effect of MIC on epididymal sperm density and morphology. EMS also had no effect on sperm density but it significantly induced morphological abnormalities in sperm as compared to untreated controls. There was an acute and transitional reduction in reproductive performance (10-21%) of MIC-exposed males during days 1-14 post-exposure followed by recovery to the normal level during days 15-21 post-exposure. The progeny of MIC-exposed males was also normal in terms of litter size, litter weight, neonatal survival and body weight gain in litters up to 10 days post-partem. It is concluded with the evidence at hand that the observed failure of MIC to cause germ cell mutagenicity is related to its poor biodistribution to the target site(s) and a transient reduction in the reproductive performance of MIC-exposed males is a result of general stress and disconsolate copulation.     

Protein and carbohydrate histochemistry in relation to the keratinization in the epidermis of Barbus sophor (Cyprinidae, Pisces)

The distribution of protein and carbohydrate constituents in the epidermis of Barbus sophor is described in order to give a better understanding of its cellular organization and physiology.
Various cytochemical techniques show the keratinized nature of the outer free margins of the polygonal cells in the most-superficial layer. These contain appreciable amounts of cysteine bound sulphydryl groups, basic proteins, protein bound NH₂ groups, ribonucleic acid and calcium and give a strong Papanicolaou's reaction. Absence of cystine bound disulphide groups suggests that the cornified layer in B. sophor is probably mechanically weak as adjacent keratin chains remain unbonded. The polygonal cells showing keratinization at the outer free margins remain metabolically active and are not sloughed off at the surface. This is in contrast to the keratinized epidermis of other teleosts so far reported in which the keratinized cells are dead and are sloughed off at the surface.
In addition to keratinization the polygonal cells undergo mucogenesis synthesizing sulphated acid mucopolysaccharides.
The presence of eosinophilic granular cells in the epidermis is interesting. The possible role of these cells in the protection of the epidermis has been discussed. The epidermis on the inner surface of the scale is very thin so it may not have much protective significance in these areas.     

Growth Analysis of Pulsed Laser Ablated Films

The spontaneous organization on a substrate of nanoparticles (NPs) nucleated in a laser-generated plasma results in self-assembling due to both direct specific interactions and to indirect ambient-mediated ones. A number of well-differentiated film morphologies are observed, from isolated NPs to percolated island structures. The distribution of the width of gaps between NPs, or islands formed upon NP coalescence in two representative percolated Au films, is lognormal, indicating that the growth process is random. A finer inspection of similar surface morphologies allows to correlate regularity in gap sizes and surface coverage to differences in film performance as substrates for surface-enhanced Raman spectroscopy.     

Novel expression system for Corynebacterium acetoacidophilum and Escherichia coli based on the T7 RNA polymerase-dependent promoter

The industrially important species of corynebacteria viz. Corynebacterium acetoacidophilum appear to be alternative hosts for recombinant protein production; despite many efforts, a strong promoter-based system in corynebacteria has not been established so far. Described here is a T7 promoter-based expression system which was functional in both gram-positive C. acetoacidophilum and gram-negative Escherichia coli in an external inducer independent manner. This is the very first report of a T7 expression system for Corynebacterium sp. Also, it is a useful addition in the existing T7 expression systems of E. coli.     

Advanced therapeutic modalities in hepatocellular carcinoma: Novel insights

Hepatocellular carcinoma (HCC), the most common type of liver cancer, is usually a latent and asymptomatic malignancy caused by different aetiologies, which is a result of various aberrant molecular heterogeneity and often diagnosed at advanced stages. The incidence and prevalence have significantly increased because of sedentary lifestyle, diabetes, chronic infection with hepatotropic viruses and exposure to aflatoxins. Due to advanced intra- or extrahepatic metastasis, recurrence is very common even after radical resection. In this paper, we highlighted novel therapeutic modalities, such as molecular-targeted therapies, targeted radionuclide therapies and epigenetic modification-based therapies. These topics are trending headlines and their combination with cell-based immunotherapies, and gene therapy has provided promising prospects for the future of HCC treatment. Moreover, a comprehensive overview of current and advanced therapeutic approaches is discussed and the advantages and limitations of each strategy are described. Finally, very recent and approved novel combined therapies and their promising results in HCC treatment have been introduced.     

Fungi causing plant diseases at jabalpur (madhya pradesh)-IX

Summary The present paper describes 6 foliicolous fungi from Jabalpur (India). These includeAsterina lawsoniae Syd. on leaves ofLawsonia alba, Diplocarpon rosae Wolf. onRosa sp.,Cercospora jujubae Chowdhury onZizyphus jujuba andCercospora subsessilis Henn. &Nym. onAzadirachta indica, new fungus records for Madhya Pradesh;Asterostomella strophanti Henn. on leaves ofFlacourtia ramontchii, a new fungus for the country andCorynespora cassiicola (Berk. &Curt.)Wei. onClerodendron inerme, a new host record.     

In vitro Production of Halo Blight Inducing Toxin by Pseudomonas phaseolicola (Burkh.) Dowson

Three pathogenic strains of Pseudomonas phaseolicola (strain 1 and 3 virulent and strain 5 weakly virulent) were tested for their toxic activity. All three strains produced detectable amounts of toxin in vitro. Cultural conditions and length of incubation greatly influenced toxin production. Maximum amount of toxin was produced at 20°C and pH 6.5. Glycerol served as the best carbon source and 1-cysteine as the best amino acid for toxin production.