Cytologic grading and DNA image cytometry of breast carcinoma on fine needle aspiration cytology smears

OBJECTIVE: To correlate the cytologic grade of breast carcinoma with DNA image cytometry (ICM) and nuclear area on fine needle aspiration cytology (FNAC) smears. STUDY DESIGN: In this prospective study, FNAC material from 28 breast carcinomas were studied for cytologic grade and DNA ICM. Breast carcinomas were classified as grade 1-3 (low to high). DNA histograms were classified by the modified Auer method. Degree of hyperploidy (DH), ploidy balance (PB) and nuclear area (NA) were measured on Feulgen-stained smears by a CAS 200 image cytometer. Cytologic grade was correlated with DNA ICM findings and NA. RESULTS: There were 3 cytologic grade 1, 13 grade 2 and 12 grade 3 breast carcinomas. Seven of eight cases of hypertetraploid aneuploidy were grade 3 tumors. All cytologic grade 1 tumors were diploid. There were significant differences in DH, PB and NA in different grades of breast carcinoma (one-way ANOVA). CONCLUSION: DNA image cytometry in combination with cytologic grading might offer additional information for the characterization of breast carcinomas diagnosed by FNAC. These observations are of particular interest with the introduction of preoperative chemotherapy.     

Accumulation of the common mitochondrial DNA deletion induced by ionizing radiation

Point mutations and deletions in mitochondrial DNA (mtDNA) accumulate as a result of oxidative stress, including ionizing radiation. As a result, dysfunctional mitochondria suffer from a decline in oxidative phosphorylation and increased release of superoxides and other reactive oxygen species (ROS). Through this mechanism, mitochondria have been implicated in a host of degenerative diseases. Associated with this type of damage, and serving as a marker of total mtDNA mutations and deletions, the accumulation of a specific 4977-bp deletion, known as the common deletion (Delta-mtDNA(4977)), takes place. The Delta-mtDNA(4977) has been reported to increase with age and during the progression of mitochondrial degeneration. The purpose of this study was to investigate whether ionizing radiation induces the formation of the common deletion in a variety of human cell lines and to determine if it is associated with cellular radiosensitivity. Cell lines used included eight normal human skin fibroblast lines, a radiosensitive non-transformed and an SV40 transformed ataxia telangiectasia (AT) homozygous fibroblast line, a Kearns Sayre Syndrome (KSS) line known to contain mitochondrial deletions, and five human tumor lines. The Delta-mtDNA(4977) was assessed by polymerase chain reaction (PCR). Significant levels of Delta-mtDNA(4977) accumulated 72 h after irradiation doses of 2, 5, 10 or 20 Gy in all of the normal lines with lower response in tumor cell lines, but the absolute amounts of the induced deletion were variable. There was no consistent dose-response relationship. SV40 transformed and non-transformed AT cell lines both showed significant induction of the deletion. However, the five tumor cell lines showed only a modest induction of the deletion, including the one line that was deficient in DNA damage repair. No relationship was found between sensitivity to radiation-induced deletions and sensitivity to cell killing by radiation.     

Fine needle aspiration cytologic diagnosis of toxoplasma lymphadenitis. A case report with detection of a Toxoplasma bradycyst in a Papanicolaou-stained smear

BACKGROUND: Fine needle aspiration (FNA) cytologic diagnosis of toxoplasmic lymphadenitis with demonstration of a tissue cyst containing bradyzoites has been very rarely reported. CASE: A 17-year-old female presented with a mobile, painless, 2-cm-diameter swelling over the right suprascapular area. Clinical diagnosis was lipoma. FNA smears showed features of reactive lymphoid hyperplasia, including tingible body macrophages and groups of epithelioid histiocytes. A Toxoplasma cyst with bradyzoites was also demonstrated in a Papanicolaou-stained smear. Following FNA cytodiagnosis, serologic tests revealed a high titer of IgG and the presence of IgM-specific antibodies to Toxoplasma gondii, indicating active/recent disease. CONCLUSION: FNA cytology is a valuable tool for the diagnosis of toxoplasmic lymphadenitis. Papanicolaou stain is appropriate for demonstration of the parasite. Serology is an excellent adjunct in clinching the diagnosis.     

Effect of age of seedling and phytohormones on micropropagation of indica rice (Oryza sativa L.) from Meristem Culture.

An efficient protocol forin vitro micropropagation of seven indica rice varieties was developed from meristem culture. Meristem (leaf base) was isolated from different age of seedlings and cultured on MS medium without hormones and supplemented with different concentrations of NAA and BAP. Regeneration of plantlets from meristem was observed within five days of culture. The meristem isolated from 4-day old seedlings gave highest regeneration on hormone free MS medium. Histological study of meristem (leaf base) from 4-day old seedlings confirmed the presence of meristematic cells. Regenerated plants were multiplied on MS medium supplemented with 0.05 mg/L NAA and 5 mg/L BAP. An average of five plants were obtained from single regenerated meristem. The plants regenerated from meristem showed morphological uniformity.     

Recent trends using natural polymeric nanofibers as supports for enzyme immobilization and catalysis

All the disciplines of science, especially biotechnology, have given continuous attention to the area of enzyme immobilization. However, the structural support made by material science intervention determines the performance of immobilized enzymes. Studies have proven that nanostructured supports can maintain better catalytic performance and improve immobilization efficiency. The recent trends in the application of nanofibers using natural polymers for enzyme immobilization have been addressed in this review article. A comprehensive survey about the immobilization strategies and their characteristics are highlighted. The natural polymers, e.g., chitin, chitosan, silk fibroin, gelatin, cellulose, and their blends with other synthetic polymers capable of immobilizing enzymes in their 1D nanofibrous form, are discussed. The multiple applications of enzymes immobilized on nanofibers in biocatalysis, biosensors, biofuels, antifouling, regenerative medicine, biomolecule degradation, etc.; some of these are discussed in this review article.     

Mapping the Progress in Surface Plasmon Resonance Analysis of Phytogenic Silver Nanoparticles with Colorimetric Sensing Applications

Nanotechnology is gaining enormous attention as the most dynamic research area in science and technology. It involves the synthesis and applications of nanomaterials in diverse fields including medical, agriculture, textiles, food technology, cosmetics, aerospace, electronics, etc. Silver nanoparticles (AgNPs) have been extensively used in such applications due to their excellent physicochemical, antibacterial, and biological properties. The use of plant extract as a biological reactor is one of the most promising solutions for the synthesis of AgNPs because this process overcomes the drawbacks of physical and chemical methods. This review article summarizes the plant-mediated synthesis process, the probable reaction mechanism, and the colorimetric sensing applications of AgNPs. Plant-mediated synthesis parameters largely affect the surface plasmon resonance (SPR) characteristic due to the changes in the size and shape of AgNPs. These changes in the size and shape of plant-mediated AgNPs are elaborately discussed here by analyzing the surface plasmon resonance characteristics. Furthermore, this article also highlights the promising applications of plant-mediated AgNPs in sensing applications regarding the detection of mercury, hydrogen peroxide, lead, and glucose. Finally, it describes the future perspective of plant-mediated AgNPs for the development of green chemistry.     

DNA recognition and cleavage by the EcoP15 restriction endonuclease.

EcoP15 is a restriction-modification enzyme coded by the P15 plasmid of Escherichia coli. We have determined the sites recognized by this enzyme on pBR322 and simian virus 40 DNA. The enzyme recognizes the sequence:

In restriction, the enzyme cleaves the DNA 25 to 26 base-pairs 3′ to this sequence to leave single-stranded 5′ protrusions two bases long.     

On the mode of action and biochemical properties of anti-inflammatory drugs-II

The inhibition of prostaglandin (PG) synthetase by nonsteroidal anti-inflammatory drugs (NSAID) is not well understood. Co-factors (glutathione and hydroquinone) are needed for maximum enzymatic activity $\text{in vitro}$, and we suggest that NSAID might inhibit PG synthetase partly by interfering with co-factor induced stimulation of the enzyme. This hypothesis was tested by:A) Examining the effect of glutathione, noradrenaline and hydroquinone on bull seminal vesicle (BSV) PG synthetase $\text{in vitro}$. The stimulatory effects were concentration-dependent.B) Three structurally distinct NSAID, indomethacin, aspirin and paracetamol, inhibited the stimulation by each co-factor in a concentration-related manner. Drug effectiveness also depended on the concentration of co-factor.     

The relative conformational stability of the alcohol dehydrogenase alleloenzymes of the fruitfly Drosophila melanogaster.

Intact spermatozoa from rat cauda epididymides possess an ecto-(cyclic AMP-dependent protein kinase) activity that causes the transfer of the terminal phosphate group of ATP to the serine residues of all the histone fractions. The enzyme showed a high degree of substrate specificity for the phosphorylation of histones rather than protamine, casein and phosvitin. The cell-external-surface protein kinase requires Mg2+ for activity, and other bivalent cations such as Mn2+ and Co2+ can substitute partially for Mg2+, whereas Ca2+ and Zn2+ are potent inhibitors of the enzyme. The enzyme has markedly higher affinity for cyclic AMP than for other cyclic nucleotides for its activation, with an apparent Km value for cyclic AmP of 80 nM. Spermatozoal ecto-kinase activity is not due to contamination of broken cells or any possible cell damage during incubation and isolation of spermatozoa. There was no loss of kinase activity from the cells when washed with 2 mM-EDTA, and the histones phosphorylated by intact spermatozoa were located outside the cells. Protein kinase activity of intact cells was strongly inhibited (approx. 90%) by p-chloromercuribenzenesulphonic acid (10 microM), which is believed not to enter the cells. These data provide further support for the localization of a protein kinase on the external surface of spermatozoa.