Comparing Arabidopsis receptor kinase and receptor protein-mediated immune signaling reveals BIK1-dependent differences.

Pattern recognition receptors (PRRs) sense microbial patterns and activate innate immunity against attempted microbial invasions. The leucine-rich repeat receptor kinases (LRR-RK) FLS2 and EFR, and the LRR receptor protein (LRR-RP) receptors RLP23 and RLP42, respectively, represent prototypical members of these two prominent and closely related PRR families. We conducted a survey of Arabidopsis thaliana immune signaling mediated by these receptors to address the question of commonalities and differences between LRR-RK and LRR-RP signaling. Quantitative differences in timing and amplitude were observed for several early immune responses, with RP-mediated responses typically being slower and more prolonged than those mediated by RKs. Activation of RLP23, but not FLS2, induced the production of camalexin. Transcriptomic analysis revealed that RLP23-regulated genes represent only a fraction of those genes differentially expressed upon FLS2 activation. Several positive and negative regulators of FLS2-signaling play similar roles in RLP23 signaling. Intriguingly, the cytoplasmic receptor kinase BIK1, a positive regulator of RK signaling, acts as a negative regulator of RP-type immune receptors in a manner dependent on BIK1 kinase activity. Our study unveiled unexpected differences in two closely related receptor systems and reports a new negative role of BIK1 in plant immunity.

Brown adipocytes can display a mammary basal myoepithelial cell phenotype in vivo.

OBJECTIVE: Previous work has suggested that white adipocytes may also show a mammary luminal secretory cell phenotype during lactation. The capacity of brown and beige/brite adipocytes to display a mammary cell phenotype and the levels at which they demonstrate such phenotypes in vivo is currently unknown. METHODS: To investigate the putative adipocyte origin of mammary gland cells, we performed genetic lineage-labeling experiments in BAT and the mammary glands. RESULTS: These studies indicated that the classic brown adipocytes (Ucp1+) and subcutaneous beige/brite adipocytes (Ucp1-/+) were found in the mammary gland during lactation, when they exhibited a mammary myoepithelial phenotype. Up to 2.5% of the anterior dorsal interscapular mammary myoepithelial cell population had a brown adipocyte origin with an adipose and myoepithelial gene signature during lactation. Eliminating these cells, along with all the brown adipocytes, significantly slowed offspring growth, potentially demonstrating their functional importance. Additionally, we showed mammary epithelial lineage Mmtv+ and Krt14+ cells expressed brown adipocyte markers after weaning, demonstrating that mammary gland cells can display an adipose phenotype. CONCLUSIONS: The identification of a brown adipocyte origin of mammary myoepithelial cells provides a novel perspective on the interrelationships between adipocytes and mammary cells with implications for our understanding of obesity and breast cancer.

Characteristics of quercetin interactions with liposomal and vacuolar membranes.

Quercetin (3,3',4',5,7-pentahydroxyflavone) is claimed to exert many beneficial health effects. With application of (1)H NMR (nuclear magnetic resonance) and FTIR (Fourier-transform infrared) techniques, quercetin interaction with liposomes formed with dipalmitoylphosphatidylcholine (DPPC) was analyzed. Patch-clamp technique was employed to study quercetin effects at single channel level of vacuolar membranes in the liverwort Conocephalum conicum. Light and electron microscopy were applied to study quercetin effects on human negroid cervix carcinoma cells (HeLa). Enzymatic measurements along with DPPH (1,1-diphenyl-2-picrylhydrazyl) bioassay were performed to investigate the influence of quercetin on antioxidant enzymes and reactive oxygen species (ROS) production. The inclusion of quercetin to the membrane exerted pronounced ordering effect on the motional freedom of lipids in the head group region as manifested by broadening of the (1)H NMR spectral line representing the choline groups. FTIR analysis revealed quercetin incorporation into DPPC liposomes via hydrogen bonding between its own hydroxyl groups and lipid polar head groups in the C-O-P-O-C segment. Both, FTIR and NMR techniques indicated also quercetin spectral effects in the region corresponding to alkyl chains. Patch-clamp experiments showed that quercetin stabilizes tonoplast and promotes a close state of SV channels. Microscopic observations of HeLa cells revealed characteristic changes in ultrastructure and morphology of the examined cells in comparison to control cells. Pretreatment of HeLa cells with quercetin alleviated H2O2-induced cell injury by improving redox balance as indicated by the increase in glutathione content and SOD (superoxide dismutase) levels as well as by the decrease in ROS level. \In conclusion, the incorporation, distribution and the changes of biophysical properties of the membranes are very important for the effectiveness of phenolic compounds as antioxidant and anticancer factors.

Limits to sustained energy intake. XVI. Body temperature and physical activity of female mice during pregnancy.

Lactation is the most energy-demanding phase of mammalian reproduction, and lactation performance may be affected by events during pregnancy. For example, food intake may be limited in late pregnancy by competition for space in the abdomen between the alimentary tract and fetuses. Hence, females may need to compensate their energy budgets during pregnancy by reducing activity and lowering body temperature. We explored the relationships between energy intake, body mass, body temperature and physical activity throughout pregnancy in the MF1 mouse. Food intake and body mass of 26 females were recorded daily throughout pregnancy. Body temperature and physical activity were monitored every minute for 23 h a day by implanted transmitters. Body temperature and physical activity declined as pregnancy advanced, while energy intake and body mass increased. Compared with a pre-mating baseline period, mice increased energy intake by 56% in late pregnancy. Although body temperature declined as pregnancy progressed, this served mostly to reverse an increase between baseline and early pregnancy. Reduced physical activity may compensate the energy budget of pregnant mice but body temperature changes do not. Over the last 3 days of pregnancy, food intake declined. Individual variation in energy intake in the last phase of pregnancy was positively related to litter size at birth. As there was no association between the increase in body mass and the decline in intake, we suggest the decline was not caused by competition for abdominal space. These data suggest overall reproductive performance is probably not constrained by events during pregnancy.

Cadmium and selenium modulate slow vacuolar channels in rape (Brassica napus) vacuoles.

Currents flowing through slow vacuolar SV channels of rape (Brassica napus) growing on media supplemented with Cd²+ (400 µM), and/or SeO4(²â») (2µM) were examined. The aim of the study was to investigate the role of Cd²+ in modulation of SV channel activity and to determine whether Se reverses the effect of cadmium. Vacuoles were isolated using a quick surgical method to avoid application of any cell wall-degrading enzymes. Vacuoles of rape exhibited typical SV channel activity with slow activation at positive potentials and strong rectification into the vacuolar lumen. Single-channel conductance in cytoplasm-side-out tonoplast patches ranged between 68.8±1.9 pS in the control, 80.1±2.5pS, in Cd²+, 74.2±2.4 pS in Cd²+/selenate, and 80.1±1.8 pS in selenate-pretreated plants. The lack of a clear tendency was likely an effect of equilibration of the pipette solution (without Cd²+/SeO4(²â») with that of the luminal side of the vesicles. In the vacuole-attached configuration, in which natural vacuolar solution was not exchanged, there was a significant reduction in single-channel conductance in the Cd²+ (40.3±2.8 pS), Cd²+/selenate (47.1±2.8 pS) and selenate-pretreated (42.3±1.4 pS) plants, compared to the control (60.2±1.7 pS). The reduction in single-channel conductance only partially explained the significant decline in the densities of ion current flowing through the vacuolar membrane in the whole-vacuole configuration in the plants growing on Cd²+ and Cd²+/selenate media. Thus, Cd²+ accumulation in the vacuole reduced the number of active SV channels from 0.28±0.05 µm⁻² in the control to 0.021±0.005 and 0.039±0.004 µm⁻² in Cd²+ and Cd²+/selenate-pretreated plants, respectively.

Genistein and changes of resting and action potentials in Conocephalum conicum.

Genistein (4',5,7-trixydroxyflavone) is a member of the family of plant flavonoids that widely occurs in crop plants. It is involved in a wide spectrum of pharmacological activities, and is suggested to have anti-cancer dietary properties. Cell membranes are one of the targets of anti-cancer drugs. In the present study, we used the liverwort Conocephalum conicum as a model plant in an electrophysiological study. Intracellular microelectrode measurements were carried out to examine the effects of genistein alone and in combination with verapamil on resting and action potentials. The application of isoflavone genistein resulted in a statistically significant elevation in action potential amplitudes. An increase of 13-62% compared with the control was noted. An increase was also found in the membrane resting potentials in genistein-treated plants. Verapamil, the known calcium channel inhibitor, caused a gradual decline of AP amplitudes, whereas preincubation of Conocephalum thalli with genistein prevented inhibition of APs by verapamil. It is concluded that genistein strongly affects the membranes, and the effect of genistein in canceling the activity of verapamil is discussed.

Long-term outcome of early treatment of developmental hip dysplasia using an abduction splint.

Background. Treatment of congenital hip dysplasia, when implemented in the first weeks of life, gives a good outcome. Very few publications, however, have addressed the anatomical remodeling of the affected hip. In this study, we evaluate the anatomical outcome of the treatment applied. Material and methods. We examined 89 children diagnosed with congenital hip dysplasia in the first three months of life and then treated with an abduction device, for a total of 148 hips. The time of follow-up varied from 8 to 13 years. All these children were given a clinical examination according to McKay, along with Severin X-ray classification. Results. Before treatment was implemented, the patients had been diagnosed as types IIc (56 hips, 37.8%), IId (34 hips, 22.9%), III (40 hips, 27.1%), and IV (18 hips, 12.2%). In one hip final assessment showed signs of aseptic necrosis of the proximal femur. 147 hips showed total remodeling, and in the Severin X-ray classification scheme were evaluated as type I. Conclusions. Severin X-ray clasification is easy to implement and in our material corresponds with the clinical evaluation according to McKay. Early implementation of treatment with an abduction device is worthwhile and gives a satisfactory outcome.

Clinical value of neonatal screening for congenital dysplasia of the hip.

Background. The problem of clinical value of neonatal screening for congenital dysplasia of the hip was described in this paper.
Material and methods. We have analyzed clinical and sonographicall documentation of a random group of 4950 children from years 1991, 1995 and 1999 treated in Outpatient Clinic for Screening of Congenital Dislocation of the Hip in Children Hospital of Medical University in Bialystok, to asses clinical value of our screening program.
Results. Congenital dysplasia (type IIb - IV according to Graf classification) was found in 3.27%, 3.3% and 2.97 of all children scanned in years 1991, 1995 and 1999 respectively. We have observed increasing number of children scanned before the end of fourth week of life (36.97%, 67.82%, 75.76% in years 1991, 1995 and 1999 respectively). The number of patients with late diagnosis of congenital hip dysplasia (after twelfth week of life) were decreasing with every year (59.26%, 16.51%, 12.24% in years 1991, 1995 and 1999 respectively). Also the number of subluxated and dislocated hips (type III and IV according to Graf classification) was decreasing with years (9, 0 and 1in years 1991, 1995 and 1999 respectively).
22 out of 108 hips with dysplasia could be included into the high risk group in year 1991 and 19 out of 109, and 22 out of 98 in years 1995 and 1999 respectively.
Conclusions. Results of our analysis allowed us to conclude that neonatal screening for congenital hip dysplasia in all newborns is very useful in preventing and treating hip subluxation and dislocation. Limiting this screening only to the children from the high risk group caries the danger of significant increase in late diagnosis of hip dysplasia and thus following dislocation of the hip.