Frequency of mutations in “thrombophilic state” genes in Uzbekistan

The frequency of mutations in a number of genetic markers, specifically factor V gene (G1691A), blood coagulation factor II gene (G20210A), and the methylenetetrahydrofolate reductase (MTHFR) gene (C677T), is studied in ethnic Uzbek patients with deep vein thrombosis of the lower extremities and in healthy donors. It is established that the incidence of mutant alleles among patients in Uzbekistan for FV Leiden is 12.9%; for prothrombin, 4%; and for MTHFR, 47.8%. The mutant allele C677T of the MTHFR gene has the highest expressivity in the appearance of MTHFR (47.8%). It is noted that this mutation in the MTHFR gene is encountered significantly more frequently in females with deep vein thrombosis than in males with deep vein thrombosis. The G20210A mutation in the prothrombin gene is encountered more rarely in the Uzbek population. The penetrance is studied and the role of these mutations in the appearance of deep vein thrombosis is estimated.     

Ionic switch controls the DNA state in phage λ

We have recently found that DNA packaged in phage λ undergoes a disordering transition triggered by temperature, which results in increased genome mobility. This solid-to-fluid like DNA transition markedly increases the number of infectious λ particles facilitating infection. However, the structural transition strongly depends on temperature and ionic conditions in the surrounding medium. Using titration microcalorimetry combined with solution X-ray scattering, we mapped both energetic and structural changes associated with transition of the encapsidated λ-DNA. Packaged DNA needs to reach a critical stress level in order for transition to occur. We varied the stress on DNA in the capsid by changing the temperature, packaged DNA length and ionic conditions. We found striking evidence that the intracapsid DNA transition is ‘switched on’ at the ionic conditions mimicking those in vivo and also at the physiologic temperature of infection at 37°C. This ion regulated on-off switch of packaged DNA mobility in turn affects viral replication. These results suggest a remarkable adaptation of phage λ to the environment of its host bacteria in the human gut. The metastable DNA state in the capsid provides a new paradigm for the physical evolution of viruses.     

Rest in the scorpion — a sleep-like state?

Summary Forest-dwelling scorpions (Heterometrus, Pandinus) were continuously observed by time-lapse video recording and their behavior and body position were analyzed. Activity recorded on the tapes was scored into three states: (1) activity, (2) alert immobility, and (3) relaxed immobility. Arousal thresholds were determined by mechanical stimulation. Responsiveness was highest during activity and alert immobility, and significantly lower during relaxed immobility. Heart rate was continuously measured by chronically implanted electrodes and related to the behavioral state. Heart rate was highest during activity, intermediate in alert immobility, and lowest during relaxed immobility. Activity bouts were associated with sudden increases in heart rate. Settling down, however, was associated with a progressive decline in heart rate.The presence of rest regulation was investigated by 12 h rest deprivation by mechanical stimulation. During recovery, after initial activation, alert immobility and relaxed immobility were decreased.It can be concluded that rest in the scorpion is not a homogeneous state. The subdivision into alert and relaxed immobility on the basis of body posture revealed differences in arousal threshold and heart rate between the two states. The compensation of rest after rest deprivation indicates the presence of regulatory mechanisms comparable with those present in mammals and several nonmammalian vertebrate species, thus providing evidence for a sleep-like state in scorpions.Abbreviations SD sleep deprivation - L light - D dark or dim - LD light-dark or dim - H Heterometrus - P Pandinus     

Electromagnetic fields in medicine – The state of art

ABSTRACT

Introduction: Intense development of methods belonging to physical medicine has been noted recently. There are treatment methods, which in many cases lead to reduction treatment time and positively influence on quality of life treatment patients. Research implications: The present physical medicine systematically extends their therapeutic possibilities. This above applies to illnesses and injuries of locomotor system, diseases affecting of soft tissues, as well as chronic wounds. The aim of the study: The evidence on this are the results of basic and clinical examinations relating the practical use of electromagnetic fields in medicine. Originality: In this work the authors introduced the procedure using the current knowledge relating to physical characteristic and biological effects of the magnetic fields. In the work the following methods were used: static magnetic fields, spatial magnetic fields, the variable magnetic fields both with laser therapy (magnetolaserotherapy) and variable magnetic fields both with light optical non-laser (magnetoledtherapy) talked.     

A residue in helical conformation in the native state adopts a β-strand conformation in the folding transition state despite its high and canonical Φ-value

Delineating structures of the transition states in protein folding reactions has provided great insight into the mechanisms by which proteins fold. The most common method for obtaining this information is Φ-value analysis, which is carried out by measuring the changes in the folding and unfolding rates caused by single amino acid substitutions at various positions within a given protein. Canonical Φ-values range between 0 and 1, and residues displaying high values within this range are interpreted to be important in stabilizing the transition state structure, and to elicit this stabilization through native-like interactions. Although very successful in defining the general features of transition state structures, Φ-value analysis can be confounded when non-native interactions stabilize this state. In addition, direct information on backbone conformation within the transition state is not provided. In the work described here, we have investigated structure formation at a conserved β-bulge (with helical conformation) in the Fyn SH3 domain by characterizing the effects of substituting all natural amino acids at one position within this structural motif. By comparing the effects on folding rates of these substitutions with database-derived local structure propensity values, we have determined that this position adopts a non-native backbone conformation in the folding transition state. This result is surprising because this position displays a high and canonical Φ-value of 0.7. This work emphasizes the potential role of non-native conformations in folding pathways and demonstrates that even positions displaying high and canonical Φ-values may, nevertheless, adopt a non-native conformation in the transition state.     

Airway smooth muscle electrophysiology in a state of flux?

Activation of chloride currents and release of internally sequestered Ca(2+) in airway smooth muscle have long been associated with excitation and contraction. Surprisingly, however, two recent publications (Deshpande DA, Wang WC, McIlmoyle EL, Robinett KS, Schillinger RM, An SS, Sham JS, Liggett SB. Nat Med 16: 1299-1304, 2010; Gallos G, Yim P, Chang S, Zhang Y, Xu D, Cook JM, Gerthoffer WT, Emala CW Sr. Am J Physiol Lung Cell Mol Physiol 302: L248-L256, 2012) have linked both events to relaxation. This begs a closer look at our understanding of airway smooth muscle electrophysiology and its contribution to excitation-contraction coupling. This Editorial Focus highlights those two aforementioned studies and several other equally paradoxical findings and proposes some possible reinterpretations of the data and/or new directions of research in which the answers might be found.     

β-Glucosidase production by Aspergillus phoenicis in solid state fermentation

Summary -glucosidase production was studied in solid-state cultivation by Aspergillus phoenicis on sugar beet pulps. The experiments were carried out in column incubators aerated with humidified air, at 30 °C. Results of physiological studies showed that the production of -glucosidase from beet pulps in the solid state fermentation required : 70% moisture content, initial pH of about 4, and 10⁷ spores/g substrate. -glucosidase produced under these conditions could be removed from the solid medium with water, or stored in the form of a dried fermented product, for a direct use in the saccharification reactions.     

The Antarctic psychrophile, Chlamydomonas subcaudata, is deficient in state I–state II transitions

State I-State II transitions were monitored in vivo and in vitro in the Antarctic, psychrophillic, green alga, Chlamydomonas subcaudata, as changes in the low-temperature (77 K) chlorophyll fluorescence emission maxima at 722 nm (F722) relative to 699 nm (F699). As expected, the control mesophillic species, Chlamydomonas reinhardtii, was able to modulate the light energy distribution between photosystem II and photosystem I in response to exposure to four different conditions: (i) dark/anaerobic conditions, (ii) a change in Mg2+ concentration, (iii) red light, and (iv) increased incubation temperature. This was correlated with the ability to phosphorylate both of its major light-harvesting polypeptides. In contrast, exposure of C. subcaudata to the same four conditions induced minimum alterations in the 77 K fluorescence emission spectra, which was correlated with the ability to phosphorylate only one of its major light-harvesting polypeptides. Thus, C. subcaudata appears to be deficient in the ability to undergo a State I-State II transition. Functionally, this is associated with alterations in the apparent redox status of the intersystem electron transport chain and with higher rates of photosystem I cyclic electron transport in the psychrophile than in the mesophile, based on in vivo P700 measurements. Structurally, this deficiency is associated with reduced levels of Psa A/B relative to D1, the absence of specific photosystem I light-harvesting polypeptides [R.M. Morgan et al. (1998) Photosynth Res 56:303-314] and a cytochrome b6/f complex that exhibits a form of cytochrome f that is approximately 7 kDa smaller than that observed in C. reinhardtii. We conclude that the Antarctic psychrophile, C. subcaudata, is an example of a natural variant deficient in State I-State II transitions.     

Triplet state dynamics in peridinin-chlorophyll-a-protein: a new pathway of photoprotection in LHCs?

This work investigates the interaction of carotenoid and chlorophyll triplet states in the peridinin-chlorophyll-a-protein (PCP) of Amphidinium carterae using step-scan Fourier transform infrared spectroscopy. We identify two carotenoid triplet state lifetimes of approximately 13 and approximately 42 mus in the spectral region between 1800 and 1100 cm(-1) after excitation of the 'blue' and 'red' peridinin (Per) conformers and the Q(y) of chlorophyll-a (Chl-a). The fast and slow decaying triplets exhibit different spectral signatures in the carbonyl region. The fast component generated at all excitation wavelengths is from a major conformer with a lactone stretching mode bleach at 1745 cm(-1). One (1720 cm(-1)) and two (1720 cm(-1) and 1741 cm(-1)) different Per conformers are observed for the slow component upon 670- and 530-480-nm excitation, respectively. The above result implies that (3)Per triplets are formed via two different pathways, corroborating and complementing visible triplet-singlet (T-S) spectra (Kleima et al., Biochemistry (2000), 39, 5184). Surprisingly, all difference spectra show that Per and Chl-a modes are simultaneously present during the (3)Per decay, implying significant involvement of (3)Chl-a in the (3)Per state. We suggest that this Per-Chl-a interaction via a delocalized triplet state lowers the (3)Per energy and thus provides a general, photoprotection mechanism for light-harvesting antenna complexes.     

Prion protein gene polymorphisms in sheep in the state of Paraná, Brazil

To determine the polymorphisms of the prion protein gene in sheep from the state of Paraná, Brazil, 323 animals of meat breeds (Suffolk, Hampshire Down, Texel, Ile de France, Dorper, Dorset, Santa Inês and crossbreds) were genotyped by restriction fragment length polymorphism (RFLP) analysis. The most frequent allele was ARQ, with a frequency of 0.61, followed by ARR (0.30). VRQ and AHQ alleles were present at very low frequencies (0.13 and 0.05 respectively), and the ARH allele was not found. Seven genotypes were identified (ARR/ARR, ARR/ARQ, ARQ/ARQ, ARR/VRQ, ARR/AHQ, ARQ/VRQ and ARQ/AHQ), of which ARQ/ARQ was the most frequent (0.41). The Santa Inês breed and crossbred animals showed the highest genotypic variability.     

Kasha or state selective behavior in the photochemistry of ortho-nitrobenzaldehyde?

The photochemistry of ortho-nitrobenzaldehyde dissolved in tetrahydrofuran was studied by means of femtosecond UV/Vis and IR spectroscopy. Comparison was made of the spectral and temporal signatures for ~400 nm and ~260 nm excitation. The 400 nm excitation promotes NBA to its lowest excited singlet state of nπ* character whereas for 260 nm an upper excited state of ππ* character is addressed. On the picosecond time scale, the molecule undergoes hydrogen transfer, yielding a ketene intermediate, internal conversion recovering the starting material, and intersystem crossing. Time constants and yields of these processes are virtually not affected by the excitation wavelength. For 400 nm excitation a ~100 fs decay component seen in the 260 nm experiment is absent, indicating that this component is due to a ππ* → nπ* internal conversion. In contrast to its formation, the decay of the ketene intermediate is influenced by the excitation wavelength. This can be attributed to different amounts of vibrational excitation.     

The discovery of state transitions in photosynthesis 40 years ago

In the late 1960s, I identified an aspect of the kinetics of chlorophyll fluorescence in algal cells that I was unable to explain in terms of photochemical quenching. I proposed a novel regulatory mechanism for the distribution of light energy to photosystems I and II, which is now known by the term of “state transitions.” I also examined the “cation-dependent redistribution of light energy” to photosystems I and II and the “energy-dependent quenching” of chlorophyll fluorescence. At that time, financial constraints prevented me from measuring the emission and action spectra of chlorophyll fluorescence at liquid-nitrogen temperature and the light quality-dependent changes in the yield of chlorophyll fluorescence at room temperature. The financial problems were solved by constructing several pieces of electronic equipment using skills obtained by repairing radios when I was a high-school and college student.     

Ethnic variation in network composition in Ürümchi: do state policies matter?

This paper examines the inter-group difference in social leverage ties between Uyghurs and Han Chinese in Ürümchi, China. Social leverage ties refer to high-status ties such as professionals and managers who can provide egos with information or access to education, training, employment, etc. Existing studies have suggested three hypotheses (i.e. retention of culture, homophily and neighbourhood poverty) for the mechanisms of ethnic differences in network composition. Based on the survey data the author collected in 2005, this paper suggests another main mechanism – state policies – in explaining the ethnic variations. State policies have led to in-group association and ethnic inequalities, which have limited Uyghur access to high-status individuals. Data analysis shows the Uyghur–Han difference in social leverage ties controlling for key background characteristics.     

Palm taxonomy in Brazilian Amazônia: The state of systematic collections in regional herbaria

Despite their economic and ecological importance, Amazonian palms have been largely neglected by contemporary taxonomists. The resulting confusion at the specific level is a serious impediment to research efforts by specialists in other fields. To assess the state of systematic collections presently available in Amazônia, we conducted a survey of the palm specimens in three Brazilian herbaria (MG, IAN and INPA). Twelve criteria were utilized to measure the quality of the specimens. We found that most of the 897 specimens are reasonably complete in a physical sense, but a large proportion lack crucial information on their labels. Curating facilities are in serious need of improvement, as is evident from the significant (26%) percentage of specimens found to be in an unreasonable state of preservation. A checklist of the 232 currently recognized palm species in Brazilian Amazônia shows that 145 (62.5%) are not represented by identified specimens, and that the representation which does exist lacks depth. To improve the quality and representativeness of collections in regional herbaria, we suggest procedures for collecting and storing palms as well as policies designed to intensify collecting efforts in Amazônia.     

Do steady state assemblages occur in shallow lentic environments from wetlands?

The Okavango Delta has an annual flood cycle that spreads slowly from the northwestern`panhandle' into a widening delta to the southeast. Rotifers were sampled from areas where the flood was active, and from other areas not yet reached by the flood. In still waters, the samples were dominated by euplanktonic rotifers, particularly of the genera Brachionus, Keratella and Hexarthra, with about 20 species per 1000 individuals at a station. Where the water was moving the samples were dominated by periphytic rotifers, with over 100 species per 1000 individuals at a single station. The periphytic species were dominated by the genus Lecane,with over 45 species, followed by Lepadellawith 24 species, and Trichocercawith 23 species. Comparison of the Okavango with six other tropical localities reveals fairly consistent ratios of the numbers of species in the periphytic genera Lecane, Lepadellaand Trichocerca,indicating that there may be assembly rules for communities of tropical periphytic rotifers.     

The cellular redox state in plant stress biology – A charging concept

Different redox-active compounds, such as ascorbate, glutathione, NAD(P)H and proteins from the thioredoxin superfamily, contribute to the general redox homeostasis in the plant cell. The myriad of interactions between redox-active compounds, and the effect of environmental parameters on them, has been encapsulated in the concept of a cellular redox state. This concept has facilitated progress in understanding stress signalling and defence in plants. However, despite the proven usefulness of the concept of a redox state, there is no single, operational definition that allows for quantitative analysis and hypothesis testing.