Finding the best antibody dilution by repeated immunostaining of the same tissue section

One can find the optimal antibody dilution for immunostaining by repeated staining on the same tissue section by using a less dilute antibody for each attempt. Using secondary antibody and horseradish peroxidase conjugated to a dextran polymer, a section stained repeatedly with several dilutions of antibody appears as good as a section stained with only the last dilution.     

Histochemical changes in neonatal liver caused by vaginal instillation of magnetic nanoparticles in pregnant mice

Drug delivery through the vagina is a novel and effective approach for treating embryonic diseases. Magnetic nanoparticles (MNPs) currently are used as drug delivery systems. The safety of MNPs for use with embryonic tissues remains unclear. We used pregnant mice to investigate the possible toxicity of MNPs toward neonatal liver at three embryonic ages using histochemical and immunohistochemical techniques. MNPs were instilled through the vaginas of pregnant mice at days 12 (E12), 15 (E15) and 17 (E17) after fertilization. We found MNPs in the neonatal liver parenchyma after delivery of the pups on day 20. We observed that MNPs caused mild apoptosis of hepatocytes, cytoplasmic vacuolation and lymphocytic infiltration in the neonatal liver after treatment at E15 compared to instillation at E12 and E17. We observed also that MNPs increased the production of caspase proteins and tumor necrosis factor receptor 2 proteins, which are indicators of apoptosis, in the neonatal liver after instillation of MNPs at E15 compared to instillation at E12 and E17. MNPs also increased the number of collagen fibers and the amounts of connective tissue growth factors in the neonatal liver parenchyma after instillation at E15 compared to instillation at E12 and E17. The general carbohydrates in the neonatal liver were decreased in a time-dependent manner after instillation at E17, E15 and E12 owing to the presence of MNPs in the parenchyma. Overall, we determined that MNPs were mildly toxic to neonatal liver.     

Histological and immunohistochemical effects of Curcuma longa on activation of rat hepatic stellate cells after cadmium induced hepatotoxicity

The liver is a target for toxic chemicals such as cadmium (Cd). When the liver is damaged, hepatic stellate cells (HSC) are activated and transformed into myofibroblast-like cells, which are responsible for liver fibrosis. Curcuma longa has been reported to exert a hepato-protective effect under various pathological conditions. We investigated the effects of C. longa administration on HSC activation in response to Cd induced hepatotoxicity. Forty adult male albino rats were divided into: group 1 (control), group 2 (Cd treated), group 3 (C. longa treated) and group 4 (Cd and C. longa treated). After 6 weeks, liver specimens were prepared for light and electron microscopy examination of histological changes and immunohistochemical localization of alpha smooth muscle actin (αSMA) as a specific marker for activated HSC. Activated HSC with a positive αSMA immune reaction were not detected in groups 1 and 3. Large numbers of activated HSC with αSMA immune reactions were observed in group 2 in addition to Cd induced hepatotoxic changes including excess collagen deposition in thickened portal triads, interlobular septa with hepatic lobulation, inflammatory cell infiltration, a significant increase in Kupffer cells and degenerated hepatocytes. In group 4, we observed a significant decrease in HSC that expressed αSMA with amelioration of the hepatotoxic changes. C. longa administration decreased HSC activation and ameliorated hepatotoxic changes caused by Cd in adult rats.     

Inventing Engineered Organoids for end-stage liver failure patients

Journal of Molecular Histology - End-stage liver disease (ESLD) is a term used clinically in reference to a group of liver diseases with liver transplantation as the choice of treatment. Due to the...     

Identifying the neural circuitry of alcohol craving and relapse vulnerability

With no further intervention, relapse rates in detoxified alcoholics are high and usually exceed 80% of all detoxified patients. It has been suggested that stress and exposure to priming doses of alcohol and to alcohol-associated stimuli (cues) contribute to the relapse risk after detoxification. This article focuses on neuronal correlates of cue responses in detoxified alcoholics. Current brain imaging studies indicate that dysfunction of dopaminergic, glutamatergic and opioidergic neurotransmission in the brain reward system (ventral striatum including the nucleus accumbens) can be associated with alcohol craving and functional brain activation in neuronal systems that process attentional relevant stimuli, reward expectancy and experience. Increased functional brain activation elicited by such alcohol-associated cues predicted an increased relapse risk, whereas high brain activity elicited by affectively positive stimuli may represent a protective factor and was correlated with a decreased prospective relapse risk. These findings are discussed with respect to psychotherapeutic and pharmacological treatment options.     

Characterization of the six zebrafish clade B fibrillar procollagen genes,with evidence for evolutionarily conserved alternative splicing within the pro-α1(V) C-propeptide

Genes for tetrapod fibrillar procollagen chains can be divided into two clades, A and B, based on sequence homologies and differences in protein domain and gene structures. Although the major fibrillar collagen types I–III comprise only clade A chains, the minor fibrillar collagen types V and XI comprise both clade A chains and the clade B chains pro-α1(V), pro-α3(V), pro-α1(XI) and pro-α2(XI), in which defects can underlie various genetic connective tissue disorders. Here we characterize the clade B procollagen chains of zebrafish. We demonstrate that in contrast to the four tetrapod clade B chains, zebrafish have six clade B chains, designated here as pro-α1(V), pro-α3(V)a and b, pro-α1(XI)a and b, and pro-α2(XI), based on synteny, sequence homologies, and features of protein domain and gene structures. Spatiotemporal expression patterns are described, as are conserved and non-conserved features that provide insights into the function and evolution of the clade B chain types. Such features include differential alternative splicing of NH₂-terminal globular sequences and the first case of a non-triple helical imperfection in the COL1 domain of a clade B, or clade A, fibrillar procollagen chain. Evidence is also provided for previously unknown and evolutionarily conserved alternative splicing within the pro-α1(V) C-propeptide, which may affect selectivity of collagen type V/XI chain associations in species ranging from zebrafish to human. Data presented herein provide insights into the nature of clade B procollagen chains and should facilitate their study in the zebrafish model system.