Relationship of a big five personality questionnaire to the symptoms of affective disorders.

Online assessments allow cost-effective, large-scale screening for psychiatric vulnerability (e.g., university undergraduates or military recruits).

International Consortium on the Genetics of Electroconvulsive Therapy and Severe Depressive Disorders (Gen-ECT-ic).

Recent genome-wide association studies have demonstrated that the genetic burden associated with depression correlates with depression severity. Therefore, conducting genetic studies of patients at the most severe end of the depressive disorder spectrum, those with treatment-resistant depression and who are prescribed electroconvulsive therapy (ECT), could lead to a better understanding of the genetic underpinnings of depression. Despite ECT being one of the most effective forms of treatment for severe depressive disorders, it is usually placed at the end of treatment algorithms of current guidelines.

Polyphenolic content, antiradical activity, stability and microbiological quality of elderberry (Sambucus nigra L.) extracts.

Background: The pharmaceutical and food industries expect detailed knowledge on the physicochemical properties of elderberry fruit extracts, their stability and microbiological quality, as well as the polyphenol content in elderberry cultivars. The characteristics of the extracts might be additionally modified by citric acid, which improves the stability of anthocyanins and protects processed fruits and syrups from pathogenic microorganisms. The choice of the method with citric acid was a consequence of the physicochemical charac teristics of elderberry pigments, which are not stable under the effect of light in alcoholic solutions.

Effects of solvents and extraction methods on the content and antiradical activity of polyphenols from fruits Actinidia arguta, Crataegus monogyna, Gaultheria procumbens and Schisandra chinensis.

Background: In line with the current tendency towards the production of the so-called safe foods, the use of environmentally-friendly methods for the extraction of polyphenols from fruits has been sought. Citric acid is a good solvent in the preparation of phenolic compounds for the food and pharmaceutical industries because it is a natural antioxidant and is non-toxic for the environment. Furthermore, new sources of polyphenols from fruit of orchard plants that are less known in Poland have been looked for.

Mental health law in Peru: work in progress.

Mental health law in Peru is developing. The Peruvian Constitution enshrines important human rights principles in relation to people with mental health problems but the enactment of such principles into national legislation is very patchy. This means that people with mental health problems, especially those admitted to hospital, may not receive optimum care and may be at risk of having their human rights breached.

Influence of locomotor training on the structure and myosin heavy chains of the denervated rat soleus muscle.

Objective: Mechanism of denervation atrophy remains poorly understood. In particular, the question about irreversibility of the late atrophy is still open. Therefore, in the present study, we investigated whether and how a passive movement can affect a progress of atrophy in rat soleus muscle.

Ionic interaction of myosin loop 2 with residues located beyond the N-terminal part of actin probed by chemical cross-linking.

To probe ionic contacts of skeletal muscle myosin with negatively charged residues located beyond the N-terminal part of actin, myosin subfragment 1 (S1) and actin split by ECP32 protease (ECP-actin) were cross-linked with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). We have found that unmodified S1 can be cross-linked not only to the N-terminal part, but also to the C-terminal 36 kDa fragment of ECP-actin. Subsequent experiments performed on S1 cleaved by elastase or trypsin indicate that the cross-linking site in S1 is located within loop 2.

Effect of nucleotide on interaction of the 567-578 segment of myosin heavy chain with actin.

To probe the effect of nucleotide on the formation of ionic contacts between actin and the 567-578 residue loop of the heavy chain of rabbit skeletal muscle myosin subfragment 1 (S1), the complexes between F-actin and proteolytic derivatives of S1 were submitted to chemical cross-linking with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. We have shown that in the absence of nucleotide both 45 kDa and 5 kDa tryptic derivatives of the central 50 kDa heavy chain fragment of S1 can be cross-linked to actin, whereas in the presence of MgADP.AlF4, only the 5 kDa fragment is involved in cross-linking reaction.

Inhibitory effect of ATP analogs and actin on the modification of myosin subfragment 1 with 9-anthroylnitrile.

The fluorescent probe, 9-anthroylnitrile (ANN), can selectively attach to Ser-180 at the ATP-binding site of subfragment 1 (S1) of skeletal muscle myosin [J. Biol. Chem.

Changes at the interface of the N- and C-terminal parts of the heavy chain of myosin subfragment 1.

It has been previously shown that in the M-MgADP-P(i) state, where the myosin head adopts a pre-power stroke conformation, treatment of trypsin-split subfragment 1 of skeletal muscle myosin with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) results in cross-linking of the C-terminal fragment of the heavy chain of S1 -- most probably its converter region -- to the N-terminal S1 heavy-chain fragment, generating a product of 44 kDa [Biochim. Biophys. Acta 1481 (2000) 55].

Interaction of the N-terminal part of the A1 essential light chain with the myosin heavy chain.

The kinetics of actin-dependent MgATPase activity of skeletal muscle myosin subfragment 1 (S1) isoform containing the A1 essential light chain differ from those of the S1 isoform containing the A2 essential light chain. The differences are due to the presence of the extra N-terminal peptide comprising 42 amino acid residues in the A1 light chain. This peptide can interact with actin; heretofore, there have no been reports of the direct interaction between this peptide and the heavy chain of S1.

Nucleotide-induced movements in the myosin head near the converter region.

Structural changes in subfragment 1 of skeletal muscle myosin were investigated by cross-linking trypsin-cleaved S1 with 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. In the absence of nucleotide the alkali light chains are cross-linked to the 27 kDa heavy chain fragment; the presence of MgATP reduces the efficiency of this reaction. On the other hand, MgATP promotes the cross-link formation between the N-terminal 27 kDa and C-terminal 20 kDa fragments of the heavy chain.

Influence of actin binding on the conformation of the central segment of the heavy chain of skeletal myosin subfragment 1.

Chymotryptic subfragment 1 (S1) of fast skeletal muscle myosin was digested with trypsin in a low ionic strength buffer in the presence of actin. Under these conditions, leading to S1-induced polymerization of actin (Cooke, R. and Morales, M.

Mapping of the region of the heavy chain of myosin subfragment 1 that can be crosslinked to the alkali light chains.

Earlier studies have shown that the presence of MgATP considerably diminishes the efficiency of crosslinking of the alkali light chains to the heavy chain of myosin subfragment 1 (S1) with dithiobis (succinimidylpropionate) (DSP). To localize the region of the nucleotide-induced change, a non-cleavable analog of DSP, disuccinimidyl suberate (DSS) was used. The products of crosslinking between the alkali light chains and the 27 kDa tryptic fragment of the heavy chain were isolated and further cleaved with N-chlorosuccinimide (NCS) or with formic acid.

Influence of nucleotide on chemical crosslinking between alkali light chains and the heavy chain of myosin subfragment 1.

When chymotryptic myosin subfragment 1 (S1) of fast skeletal muscle myosin is treated with dithiobis(succinimidylpropionate) (DSP), the alkali light chains A1 and A2 become intramolecularly crosslinked to the N-terminal 27 kDa fragment of the S1 heavy chain (Labbé et al. (1981) Biochem. Biophys.

Dependence of the length of the heavy chain of chymotryptic subfragment 1 on the temperature of myosin digestion.

Limited digestion of filamentous myosin with chymotrypsin at 0 degrees C in the absence of divalent cations generates two forms of subfragment 1 (S1), with heavy chains of 95 kDa and 98 kDa. The difference is at the C-terminal end of the chain. The 98 kDa form prevails, in contrast to the preparations obtained by digestion at room temperature which consist of the shorter species and only traces of the longer one.

Crosslinking of trypsin digested acto-heavy meromyosin as a probe of the affinity of the two myosin heads to actin.

The interaction of the two heads of the myosin molecule with actin was studied by tryptic digestion of HMM in the presence of actin, followed by crosslinking the two nicked heavy chains with Nbs2 at the S2 region. In view of the protection by actin of the 50/60 kDa junction against proteolysis, the percentage of the heads interacting with actin was estimated from the proportion of the 110 kDa to the 60 kDa digestion product. Under conditions such that about 50% of HMM heads were protected by actin (at an actin to HMM head molar ratio of 1:1 in the absence of nucleotide, or 3:1 in the presence of 5 mM ADP), the crosslinking of the digestion products yielded a 230 kDa (110 + 110 kDa), 125 kDa (60 + 60 kDa) and 175 kDa (60 + 110 kDa) species.

Reactivities of thiols in myosin rod: effect of magnesium and ionic strength.

There are six cysteines in each chain of myosin rod of rabbit skeletal muscle: three are in the S-2 portion, at residues 66, 108 and 410 (Lu, R.C. and Lehrer, S.

Unusual features of the Ca2+-ATPase activity of myosin from fast skeletal muscle of the frog: effect of actin and SH1 thiol group modification.

The K+-ATPase and actin-activated Mg2+-ATPase activity of myosin from fast skeletal muscle of the frog, Rana esculenta or Rana temporaria, are comparable to the respective activities of rabbit fast skeletal muscle. On the other hand, the Ca2+-ATPase activity of the same preparations of frog myosin is 6-7-fold lower than that of myosin from rabbit muscle. Various control experiments indicate that the small extent of Ca2+ stimulation is an intrinsic property of frog muscle myosin.

Comparison of myosin isoenzymes from slow-tonic and fast-twitch fibers of frog muscle.

Myosin from distal cruralis bundle of triceps femoris composed of slow-tonic and fast-twitch fibers in an about 1 to 1 ratio, from rectus abdominis containing a lower proportion of slow-tonic fibers, and from a fast-twitch sartorius muscle of the frog, was characterized by means of polyacrylamide gel electrophoresis in the presence of sodium dodecylsulphate (SDS), electrophoresis in non-dissociating conditions, and determination of the ATPase activity. SDS-polyacrylamide gel electrophoresis failed to reveal the presence of any specific light chain in myosin from slow-tonic fibers. Light chains having the same mobilities as fast-twitch LC1 and LC2 were observed; as previously described by Focant and Reznik [15], myosin from tonic fibers appears, on the other hand, devoid of LC3.

Changes in the ultrastructure of actomyosin gel during hydrolysis of ATP under various ionic conditions.

The interaction of myosin and actin in the presence of MgATP under various ionic conditions was investigated by a simultaneous determination of changes in turbidity, liberation of inorganic phosphate, distribution of the two proteins between the supernatant and precipitate obtained after a short-time centrifugation, and by electron microscopy. The results confirm the view that the extent of association between myosin and actin filaments is low not only in the clear phase but also under the conditions when the addition of MgATP results in superprecipitation without a detectable clear phase. Extensive formation of aggregates of parallelly aligned myosin and actin filaments coincides with the depletion of ATP, indicating that these aggregates represent rigor complexes.