Observing the Temperature Dependent Transition of the GP2 Peptide Using Terahertz Spectroscopy

The GP2 peptide is derived from the Human Epidermal growth factor Receptor 2 (HER2/nue), a marker protein for breast cancer present in saliva. In this paper we study the temperature dependent behavior of hydrated GP2 at terahertz frequencies and find that the peptide undergoes a dynamic transition between 200 and 220 K. By fitting suitable molecular models to the frequency response we determine the molecular processes involved above and below the transition temperature (T _D). In particular, we show that below T _D the dynamic transition is dominated by a simple harmonic vibration with a slow and temperature dependent relaxation time constant and that above T _D, the dynamic behavior is governed by two oscillators, one of which has a fast and temperature independent relaxation time constant and the other of which is a heavily damped oscillator with a slow and temperature dependent time constant. Furthermore a red shifting of the characteristic frequency of the damped oscillator was observed, confirming the presence of a non-harmonic vibration potential. Our measurements and modeling of GP2 highlight the unique capabilities of THz spectroscopy for protein characterization.     

Walnut diet reduces accumulation of polyubiquitinated proteins and inflammation in the brain of aged rats

An increase in the aggregation of misfolded/damaged polyubiquitinated proteins has been the hallmark of many age-related neurodegenerative diseases. The accumulation of these potentially toxic proteins in brain increases with age, in part due to increased oxidative and inflammatory stresses. Walnuts, rich in omega fatty acids, have been shown to improve memory, cognition and neuronal effects related to oxidative stress (OS) and inflammation (INF) in animals and human trials. The current study found that feeding 19-month-old rats with a 6% or 9% walnut diet significantly reduced the aggregation of polyubiquitinated proteins and activated autophagy, a neuronal housekeeping function, in the striatum and hippocampus. Walnut-fed animals exhibited up-regulation of autophagy through inhibiting phosphorylation of mTOR, up-regulating ATG7 and Beclin 1, and turnover of MAP1BLC3 proteins. The clearance of polyubiquitinated protein aggregates such as p62/SQSTM1 was more profound in hippocampus, a critical region in the brain involved in memory and cognitive performance, than striatum. The clearance of ubiquitinated aggregates was in tandem with significant reductions in OS/INF, as indicated by the levels of P38-MAP kinase and phosphorylations of nuclear factor kappa B and cyclic AMP response element binding protein. The results demonstrate the effectiveness of a walnut-supplemented diet in activating the autophagy function in brain beyond its traditionally known antioxidant and anti-inflammatory benefits.     

Preliminary observations on the interstitial fauna of the south-west coast of India

Summary This paper presents the preliminary observations on the interstitial fauna of the south-west coast of India, made during the course of 1963–1964. Observations were made at four stations representing different ecological habitats. The influence of some factors, such as wave action, grain size, temperature and salinity on the fauna was studied. The occurrence, seasonal abundance and the nature of distribution of the different groups on the intertidal zone, were also studied at the four stations.     

Cloning and identification of bacteriophage T4 gene 2 product gp2 and action of gp2 on infecting DNA in vivo.

We sequenced bacteriophage T4 genes 2 and 3 and the putative C-terminal portion of gene 50. They were found to have appropriate open reading frames directed counterclockwise on the T4 map. Mutations in genes 2 and 64 were shown to be in the same open reading frame, which we now call gene 2. This gene codes for a protein of 27,068 daltons. The open reading frame corresponding to gene 3 codes for a protein of 20,634 daltons. Appropriate bands on polyacrylamide gels were identified at 30 and 20 kilodaltons, respectively. We found that the product of the cloned gene 2 can protect T4 DNA double-stranded ends from exonuclease V action.     

Mitogenic response of rat lung and tracheal epithelial cells in monolayer primary cultures—Modulation of TNF-α expression

Epithelial cells isolated from rat lung and trachea were grown on monolayers and their response to a number of hormones and growth factors were studied. Maximum proliferative response in serum containing media was observed when insulin, cholera toxin and cortisol were present together. However, these additives when present independently showed a marginal response. The synergism, due to these factors in promoting growth was seen very early in culture (day 4) as shown by thymidine labelling studies, On examining the indices of early mitogenesis, such as the expression ofc-myc, our data suggests that these factors stimulate the expression ofc-myc within 4 h. With respect to expression of TNF-α mRNA, this study suggests a possible modulation of TNF-α expression in response to these mitogens that stimulate proliferation maximally. Whether this expression of TNF-α by these epithelial cells is due to a maximal proliferative stimulus and/or is an early step in the cascade of intracellular signalling events is to be investigated in detail.     

Total cholesterol concentration in relation to superovulatory responses in crossbred cows

Blood serum total cholesterol levels of crossbred Taur-indicus donor cows (n=22), in their 1st to 4th parity, were studied as an indicator of embryo yield. These cows were superovulated either with FSH or PMSG + anti-PMSG on the 12th day of the synchronized estrous cycle. The total and transferable number of embryos did not differ significantly between the treatment groups. The number of corpora lutea and total and transferable embryos in donors having total cholesterol levels <140 mg/dl were significantly (P < 0.05) lower than those of cows having >140 mg/dl, indicating that low total cholesterol levels might adversely affect superovulatory response. Thus, estimation of total cholesterol concentrations of potential donors can be a useful tool for predicting superovulatory responses.     

The isolation of a bacterial glycoprotein with luciferase activity

Luciferase from the luminescent bacteria Photobacterium leiognathi, strain S-1, has been isolated and purified from lysed cells and shown to be a glycoprotein. A soluble, non-carbohydrate containing luciferase was also isolated from the lysate. This latter luciferase amounts to less than 20% of the total luciferase activity. The purified glycoprotein is (1) susceptible to inactivation by lysozyme, (2) gives positive color reactions to the phenol, resorcinol, and anthrone tests for sugars, and (3) gives overlapping bands when stained for carbohydrate and protein on gel electrophoresis. Neither the soluble luciferase from S-1 nor a soluble luciferase isolated from Beneckea harveyi, mutant MB-20, give positive results to any of these carbohydrate tests.     

Monoclonal antibodies to a nitroxide lipid hapten

The isolation and characterization of a hybridoma cell line producing a monoclonal IgG₁ antibody against a spin-label nitroxide group is described. The antibody recognizes a synthetic hapten containing linked dinitrophenyl and 2,2,6,6-tetramethylpiperidinyl 1-oxy groups, having an affinity of 3.6±1.0·10⁶ M^?1 for the soluble hapten at 25°C. The antibody binds to phospholipid vesicles containing 2 mol% of spin label-derivitized lipid (lipid hapten) with an affinity of 1.5±0.2·10⁸ M^?1. This monoclonal IgG₁ mediates the binding of hapten-bearing lipid vesicles to mouse macrophage RAW264 cells bearing Fc receptors. The cellular responses to this binding are similar to those observed previously using polyclonal rabbit anti-hapten IgG. As with the heterogeneous antibodies, the monoclonal IgG₁ is more efficient in mediating cellular uptake when the vesicles are in the ‘fluid’ physical state (dimyristoylphosphatidylcholine at 37°C) compared to ‘solid’ (dipalmitoylphosphatidylcholine at 37°C). Despite the enhanced binding of ‘fluid’ phospholipid vesicles to cells, only the ‘solid’ vesicles triggered a significant respiratory burst in RAW264 macrophages.     

Correlation between chronological age and skeletal age using cvmi and modified MP3 methods

Chronological age conveys only a rough approximation of the maturational status of a person whereas skeletal maturity indicators give a more accurate estimation. Therefore, it is of interest to document the correlation between chronological and skeletal age using CVMI and modified MP3 methods. A total of 39 subjects between the age ranges of 9-16 years were selected for this study. Pre-treatment lateral cephalograms and hand-wrist radiographs of the subjects were used. The skeletal age was analyzed by the Cervical Vertebrae Maturity Index (CVMI) and modified MP3 methods. The data was analyzed with SPSS software version 23.00. Kendall''s Tau correlation test was performed to estimate the correlation between chronological age and skeletal age among the subjects and a linear regression test was also performed. Positive correlation was found between chronological age and skeletal age assessed by CVMI method (r= 0.398) and modified MP3 method (r=0.382) with p value >0.003. Thus it can be concluded that there was a positive correlation between chronological age and skeletal age among all the subjects.