IgG-2 deficiency in gangrenous mastitis in cows

In bovine species 4 classes of immunoglobulins have been identified. Murphy et al. (1965) have demonstrated the presence of IgM, while Mach et al. (1969) and Vaerman (1970) have described the presence of IgA in cattle sera. Two subclasses of IgG (IgG-1 and IgG-2) have been described and characterized by Murphy et al., Pierce & Feinstein (1965), and Aalund (1968). Nansen (1970) prefers to designate these subclasses as IgG-fast and IgG-slow. However, it seems to be the general tendency to accept the nomenclature IgG-1 and IgG-2.     

Tunability and noise dependence in differentiation dynamics

The dynamic process of differentiation depends on the architecture, quantitative parameters, and noise of underlying genetic circuits. However, it remains unclear how these elements combine to control cellular behavior. We analyzed the probabilistic and transient differentiation of Bacillus subtilis cells into the state of competence. A few key parameters independently tuned the frequency of initiation and the duration of competence episodes and allowed the circuit to access different dynamic regimes, including oscillation. Altering circuit architecture showed that the duration of competence events can be made more precise. We used an experimental method to reduce global cellular noise and showed that noise levels are correlated with frequency of differentiation events. Together, the data reveal a noise-dependent circuit that is remarkably resilient and tunable in terms of its dynamic behavior.     

Transformation of a star into a planet in a millisecond pulsar binary

Millisecond pulsars are thought to be neutron stars that have been spun-up by accretion of matter from a binary companion. Although most are in binary systems, some 30% are solitary, and their origin is therefore mysterious. PSR J1719-1438, a 5.7-millisecond pulsar, was detected in a recent survey with the Parkes 64-meter radio telescope. We show that this pulsar is in a binary system with an orbital period of 2.2 hours. The mass of its companion is near that of Jupiter, but its minimum density of 23 grams per cubic centimeter suggests that it may be an ultralow-mass carbon white dwarf. This system may thus have once been an ultracompact low-mass x-ray binary, where the companion narrowly avoided complete destruction.     

TRB3: a tribbles homolog that inhibits Akt/PKB activation by insulin in liver

Insulin resistance is a major hallmark in the development of type II diabetes, which is characterized by the failure of insulin to promote glucose uptake in muscle and to suppress glucose production in liver. The serine-threonine kinase Akt (PKB) is a principal target of insulin signaling that inhibits hepatic glucose output when glucose is available from food. Here we show that TRB3, a mammalian homolog of Drosophila tribbles, functions as a negative modulator of Akt. TRB3 expression is induced in liver under fasting conditions, and TRB3 disrupts insulin signaling by binding directly to Akt and blocking activation of the kinase. Amounts of TRB3 RNA and protein were increased in livers of db/db diabetic mice compared with those in wild-type mice. Hepatic overexpression of TRB3 in amounts comparable to those in db/db mice promoted hyperglycemia and glucose intolerance. Our results suggest that, by interfering with Akt activation, TRB3 contributes to insulin resistance in individuals with susceptibility to type II diabetes.     

Characterization of an EMS-induced soybean mutant with an increased content of Af saponin and a new component Ab-δ in the seed hypocotyl

Saponins are one of the components present in the soybean seeds that have various functional properties. The chemical structures and concentration of soyasaponins affect the taste of the processed soyfood, thereby limiting its industrial applications. Therefore, it is important to understand saponin biosynthesis to explore natural and artificial variation in the saponin components, which can be modified to suit its application. The objective of the present study was to identify and characterize an EMS-induced soybean mutant with an altered saponin composition from a pool of 892 M4 lines. The mutant PE1905 showed an increased content of saponin Af (336.0%). The content of saponin Ab, DDMP-αg, and DDMP-βg was decreased in the mutant PE1905 by 89.3, 24.8, and 63.1%, respectively compared to the wild-type Pungsannamul. Additionally, four new components were detected in the mutant PE1905 that were absent in the wild type. Of these, the compound 4 (designated as Ab-δ) had the highest concentration, and therefore it was further characterized by HPLC and LC-PDA/MS/MS analysis to know the chemical structure, and molecular weight and formula. Considering these details, along with the alterations in the saponin Af and Ab concentrations, it was presumed that the Ab-δ acts as a precursor for the synthesis of saponin Af and Ab. Thus, we predicted a biosynthetic pathway from the Ab-δ to Ab saponin. The inheritance analysis showed that the concentration of saponin Ab-δ is controlled by a single recessive gene in the mutant PE1905. The results from the present study would be helpful in understanding the mechanisms behind altered seed saponin composition in soybeans.     

Mobilization of organic reserves during ovarian development in a marine penaeid prawn,Parapenaeopsis hardwickii (Miers) (Crustacea,Decapoda, Penaeidae)

The present study furnishes data concerning changes in biochemical constituents of midgut gland and ovary of Parapenaeopsis hardwickii associated with ovarian development. The ovarian index (0I) increased as the ovary developed from stage I (0I = 2.80 ± 0.32) to stage IV (0I = 5.85 ± 0.38) and then decreased suddenly in stage V (0I = 1.20 ± 0.45) following spawning. Associated biochemical parameters (protein, glycogen and fat) show remarkable variation. There was a continuous decline in these parameters in the midgut gland during ovarian development and a similar increase in their concentration in the ovary. The physiological significance of these findings is discussed briefly.