A study of lipid- and protein- bound sialic acids for the diagnosis of bladder cancer and their relationships with the severity of malignancy

Background:

The gold standard for detection of bladder cancer is cystoscopy, which is an invasive and complicated procedure. Our study was conducted to find a tumor marker with high specificity, sensitivity, and accuracy for the diagnosis of bladder cancer.

Methods:

Serum samples were collected from 58 bladder cancer patients and 60 healthy control subjects. Levels of lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured spectrophotometrically by Aminoff’s method.

Results:

Mean levels of both markers were found to be significantly higher in the patients than the healthy controls. Positive correlations were observed between serum levels of lipid- (r=0.283, p<0.05) and protein- bound (r=0.56, p<0.05) sialic acids and the grade of malignancy. To differentiate patients with bladder tumors from healthy controls, cut-offpoints were determined for each of the two parameters based on Receiver Operating Characteristic (ROC) curve analysis (LBSA=21.25 mg/dL, PBSA=6.15 mg/dL). The data showed good sensitivities (LBSA=89%, PBSA=79%), specificities (LBSA=70%, PBSA=70%) and accuracies (LBSA=83%, PBSA=81%) for both markers.

Conclusion:

Measuring serum LBSA and PBSA by this simple, reproducible, noninvasive, and inexpensive method can accurately discriminate cancer patients from healthy individuals. Key Words: Urinary Bladder Neoplasms, N-Acetylneuraminic Acid, Tumor Markers     

Effect of demecolcine (colcemid) on goldfish oocyte meiosis in Vitro

Germinal vesicle migration (GVM) and dissolution (GVD) were studied in goldfish oocytes treated with 17-α,20–β-dihydroxyprogesterone (DHP) and/or demecolcine (DE; a colchicine derivative also known as colcemid) in vitro. DE (100 μg/ml) in the presence of DHP, enhanced steroid-induced GVM, after both 24 and 48 hr of incubation and significantly reduced the DHP ED₅₀ value for GVM. Similarly, administration of DE alone elicited a significant, dose-related increase in GVM after 24 or 48 hr of incubation. The presence of DE, either alone or in combination with DHP, was without effect on GVD. The effect of DE was also tested on ooplasmic viscoelasticity in goldfish follicles subjected to a centrifugal force (160g for 1 min). Preincubation (24 hr) of goldfish follicles in DE significantly influenced the direction and the extent of the centrifugally induced GV movement along the axis of centrifugal force in a dose-related fashion. The present results provide support for the hypothesis that cytoskeletal components, such as microtubules that are sensitive to DE, are involved in the mechanism of GVM in goldfish oocytes.     

Differential pulse voltammetric simultaneous determination of acetaminophen and ascorbic acid using single-walled carbon nanotube-modified carbon-ceramic electrode

Single-walled carbon nanotube-modified carbon–ceramic electrode (SWCNT/CCE) was employed for the simultaneous determination of acetaminophen (APAP) and ascorbic acid (AA). The SWCNT/CCE displayed excellent electrochemical catalytic activities toward APAP and AA oxidation compared with bare CCE. In the differential pulse voltammetry technique, both AA and APAP gave sensitive oxidation peaks at −62 and 302 mV versus saturated calomel electrode, respectively. Under the optimized experimental conditions, APAP and AA gave linear responses over ranges of 0.2 to 150.0 μM (R² = 0.998) and 5.0 to 700.0 μM (R² = 0.992), respectively. The lower detection limits were found to be 0.12 μM for APAP and 3.0 μM for AA. The investigated method showed good stability, reproducibility, and repeatability as well as high recovery in pharmaceutical and biological samples.     

Ultrastructure of islet microcirculation, pericytes and the islet exocrine interface in the HIP rat model of diabetes

CONTEXT: The transgenic human islet amyloid polypeptide (HIP) rat model of type 2 diabetes mellitus (T2DM) parallels the functional and structural changes in human islets with T2DM. OBJECTIVE: The transmission electron microscope (TEM) was utilized to observe the ultrastructural changes in islet microcirculation. METHODS: Pancreatic tissue from male Sprague Dawley rats (2, 4, 8, 14 months) were used as controls (SDC) and compared to the 2-, 4-, 8- and 14-month-old HIP rat models. RESULTS: The 2-month-old HIP model demonstrated no islet or microcirculation remodeling changes when compared to the SDC models. The 4-month-old HIP model demonstrated significant pericapillary amyloid deposition and diminution of pericyte foot processes as compared to the SDC models. The 8-month-old model demonstrated extensive islet amyloid deposition associated with pericyte and beta-cell apoptosis when compared with SDC. The 14-month-old HIP model demonstrated a marked reduction of beta-cells and intra-islet capillaries with near complete replacement of islets by amyloidoses. Increased cellularity in the region of the islet exocrine interface was noted in the 4- to 14-month-old HIP models as compared to SDC. In contrast to intra-islet capillary rarefaction there was noticeable angiogenesis in the islet exocrine interface. Pericytes seemed to be closely associated with collagenosis, intra-islet adipogenesis and angiogenesis in the islet exocrine interface. CONCLUSION: The above novel findings regarding the microcirculation and pericytes could assist researchers and clinicians in a better morphological understanding of T2DM and lead to new strategies for prevention and treatment of T2DM.     

Physiological and genetic characterization of rice nitrogen fixer PGPR isolated from rhizosphere soils of different crops

Aims

We aimed to identify plant growth-promoting rhizobacteria that could be used to develop a biofertilizer for rice.

Methods

To obtain plant growth-promoting rhizobacteria, rhizosphere soils from different crops (rice, wheat, oats, crabgrass, maize, ryegrass, and sweet potato) were inoculated to rice plants. In total, 166 different bacteria were isolated and their plant growth-promoting traits were evaluated in terms of colony morphology, indole-3-acetic acid production, acetylene reduction activity, and phosphate solubilization activity. Moreover, genetic analysis was carried out to evaluate their phylogenetic relationships based on 16S rRNA sequence data.

Results

Strains of Bacillus altitudinis, Pseudomonas monteilii, and Pseudomonas mandelii formed associations with rice plants and fixed nitrogen. A strain of Rhizobium daejeonense showed nitrogen fixation activity in an in vitro assay and in vivo. Strains of B. altitudinis and R. daejeonense derived from rice rhizosphere soil, strains of P. monteilii and Enterobacter cloacae derived from wheat rhizosphere soil, and a strain of Bacillus pumilus derived from maize rhizosphere soil significantly promoted rice plant growth.

Conclusions

These methods are effective to identify candidate species that could be developed as biofertilizers for target crops.     

Soft Vibrational Modes Predict Breaking Events during Force-Induced Protein Unfolding

We investigate the correlation between soft vibrational modes and unfolding events in simulated force spectroscopy of proteins. Unfolding trajectories are obtained from molecular dynamics simulations of a Gō model of a monomer of a mutant of superoxide dismutase 1 protein containing all heavy atoms in the protein, and a normal mode analysis is performed based on the anisotropic network model. We show that a softness map constructed from the superposition of the amplitudes of localized soft modes correlates with unfolding events at different stages of the unfolding process. Soft residues are up to eight times more likely to undergo disruption of native structure than the average amino acid. The memory of the softness map is retained for extensions of up to several nanometers, but decorrelates more rapidly during force drops.     

Design and synthesis of a gonadotropin-releasing hormone (GnRH) analogue, [Tyr(OMe)5,d-Glu6,Aze9]GnRH: Receptor binding, gonadotropin release and ovulation studies

Summary Gonadotropin-releasing hormone (GnRH) stimulates the release and synthesis of gonadotropin hormones (GtH) and is the key regulator of reproduction. The present study was carried out to design a potent GnRH analogue containing Tyr(OMe) at position 5 and ad-amino acid at position 6. This was based on a previous study in which [Tyr(OMe)⁵]GnRH was shown to have reduced potency compared to GnRH. A novel GnRH peptide containing Tyr(OMe)⁵ andd-Glu⁶ in combination with other substitutions at positions 9 and 10 was synthesized in the present study and tested for binding to the rat pituitary as well as potency in terms of gonadotropin (GtH) release in the goldfish pituitary and ovulation in sea bass. The results demonstrate that the replacement of the glycine residue at position 6 with ad-Glu in combination with the substitution of proline at position 9 with azetidine (Aze) increased the binding and biological activity of [Tyr(OMe)⁵]GnRH. The observed increased potency is likely to be related to the improved resistance to degradation. The present findings may lead to the development of a more potent GnRH agonist for inducing ovulation in fish.     

Isolation of some new sulphur bacteria from activated sludge

E mtiazi , G., H abibi , M.H. & S etareh , M. 1990. Isolation of some new sulphur bacteria from activated sludge. Journal of Applied Bacteriology 69 , 864–870.
During studies on bulking of activated sludge some new sulphur micro-organisms, which were able to grow aerobically and anaerobically on reduced sulphur compounds, were isolated on thiosulphate agar. These were capable of autotrophic and heterotrophic growth on a wide range of substrates. In view of their ability to oxidize reduced sulphur compounds, and because one of them was an oxidase- and catalase-positive, Gram-negative, motile coccus (0.36–0.48 μm) it was named Thiosphaera persica . The second one was an oxidase- and catalase-positive, Gram-negative, motile rod (1.32–1.80 μm) and was named Thiobacillus persica . The third one was oxidase-negative, catalase-positive, motile, Gram-negative and polymorphic and was named Sulphobacter polymorpha .     

Isolation and structure of d-xylans from pericarp seeds of Opuntia ficus-indica prickly pear fruits

Xylans were isolated from the pericarp of prickly pear seeds of Opuntia ficus-indica (OFI) by alkaline extraction, fractionated by precipitation and purified. Six fractions were obtained and characterized by sugar analysis and NMR spectroscopy. They were assumed to be (4-O-methyl-d-glucurono)-d-xylans, with 4-O-α-d-glucopyranosyluronic acid groups linked at C-2 of a (1→4)-β-d-xylan. The sugar composition and the ¹H and ¹³C NMR spectra showed that their chemical structures were very similar, but with different proportions of d-Xyl and 4-O-Me-d-GlcA. Our results showed that, on average, the water soluble xylans have one nonreducing terminal residue of 4-O-methyl-d-glucuronic acid for every 11 to 14 xylose units, whereas in the water non-soluble xylans, xylose units can varied from 18 to 65 residues for one nonreducing terminal residue of 4-O-methyl-d-glucuronic acid.     

Emerging roles of epigenetic mechanisms in Parkinson’s disease

Epigenetic mechanisms have emerged as important components of a variety of human diseases, including cancer and central nervous system disorders. Despite recent studies highlighting the role of epigenetic mechanisms in several neurodegenerative and neuropsychiatric disorders, to date, there has been a paucity of studies exploring the role of epigenetic factors in Parkinson’s disease (PD). PD is a progressive neurological disorder with characteristic motor and non-motor symptoms, including a range of neuropsychiatric features, for which neither preventative nor effective long-term treatment strategies are available. It is one of the most common neurodegenerative disorders and the second most prevalent after Alzheimer’s disease. In this review, we present several lines of evidence suggesting that epigenetic factors may play an important role in the pathogenesis of PD and propose on this basis a framework to guide future investigations into epigenetic mechanisms and systems biology of PD. These notions, together with technical advances in the ability to perform genome-wide analysis of epigenomic states, and newly available small-molecule probes targeting chromatin-modifying enzymes, may help design new treatment strategies for PD and other human diseases involving epigenetic dysregulation.