THE EFFECT OF MELATONIN ON THE SERUM LEVEL OF INTERLEUKIN 31 IN HERPESVIRUS SKIN DISEASES ON THE BACKGROUND OF HIV

The immune system of the skin is the first line of defense against various infections, on the other hand, its strategic location as a key barrier between external and internal environment makes the skin an important tool for maintaining homeostasis, so dermatological lesions are often a manifestation of various pathological conditions. Thus, herpesvirus skin diseases, which are the result of reactivation of a latent infection and occur against the background of human immunodeficiency, may be the first manifestation of HIV. Active study of melatonin in recent years in the dermatological field is associated with interest in its biological action, which extends to the skin due to the melatoninergic system, and promising prospects for the development of new treatments. The aim of this study was to investigate the effect of melatonin on the serum levels of interleukin 31 in herpesvirus skin diseases on the background of HIV. The current study selected 40 HIV patients who had an acute herpesvirus infection caused by HSV-1, HSV-2, VZV, EBV, and HHV-8 were selected. Patients were divided into two groups: group I consisted of patients receiving antiretroviral therapy, valaciclovir in standard therapeutic doses and melatonin as immunomodulatory therapy. Patients in the melatonin group received two melatonin tablet, 3 mg for 14 days, 6 mg daily (two doses of 3 mg). Group II included patients who received antiretroviral therapy in combination with valaciclovir. Serum levels of IL-31 were measured before and after 14 days of therapeutic intervention. The mean serum level of IL-31 was significantly lower in the melatonin group (p˂0.05). Also, in both groups, serum levels of IL-31 showed a significant increase compared to the indicator of the norm. The results of this study showed that melatonin administration could modify inflammatory cytokines secretion such as IL-31. Given the low toxicity of melatonin and its ability to reduce side effects and increase the efficiency of therapeutic agents, its use may be important and significant in combined therapy in combination with highly active antiretroviral therapy.

Working memory and abstract thinking in patients with schizophrenic spectrum disorders

Introduction

According to a selective meta-analytical review, weakness of working memory is considered as one of the fundamental disorders in schizophrenia. Some researchers propose identifying this disorder as an endophenotypic marker of schizophrenia diathesis. Many researchers also emphasize violations of “abstract thinking”, that is, the ability of patients to operate with abstract concepts. Many scientists understand the violation of “abstract thinking” as the difficulty of patient in operating with the dominant signs of the concept. Based on these approaches, we assume a dark relationship between working memory and abstract thinking.

Objectives

The aim of this study is to investigate the relationship between working memory and abstract thinking defect in patients with schizophrenic spectrum disorders.

Methods

16 patients with schizophrenic spectrum disorders were studied. To study abstract thinking, the following neuropsychological and psychometric techniques were used: exclusion of objects, D-KEFS understanding of proverbs (latent concepts were recorded). The following techniques were used to study working memory: n-back; Wechsler Test, subtest Digit Repetition.

Results

As a result of preliminary research, the following data was obtained. We found significant differences between the number of irrelevant features (which corresponds to impaired abstract thinking) and the severity of impaired working memory (p = 0.035). The more the memory was impaired, the more the subjects demonstrated the impairment of abstract thinking.

Conclusions

Thus, our results justify our assumption. A relationship between working memory and abstract thinking is founded to be possible. Further studies of this issue requires a wider techniques battery as well as a larger sample.

Conflict of interest

The reported study was funded by RFBR, project number 20-013-00772

COVID-19 and gastrointestinal injury: a brief systematic review and data from Bulgaria

In December 2019, a new Coronavirus (SARS-CoV-2) emerged in China, causing the pandemic disease COVID-19. The clinical presentation is variable, but the predominant symptoms are those of the upper respiratory tract.

AIM

The aim of the current study is to describe the incidence and type of the gastrointestinal injury (GI) in COVID-19, as well as their prognostic value.

MATERIALS AND METHODS

We conducted a coincidental search on this topic in PubMed, Web of Science and EMBASE. We also followed a group of 31 Bulgarian COVID-19 patients throughout the course of their disease and analyzed their symptoms (catarrhal and other) and outcome.

RESULTS

The publications concerning our survey followed a total of 1509 COVID-19 patients. In the Bulgarian cohort, only 14 from the 31 patients were laboratory-confirmed COVID-19 cases. Approximately 1/3 of the infected individuals presented with GI. In some patients this was the first, or only, symptom of the disease. It was also indicative of a more severe disease course.

CONCLUSION

GI may be an important symptom and prognostic factor in COVID-19. Therefore, patients with acute gastrointestinal symptoms must be actively tested for SARS-CoV-2.

Involvement of the gallbladder in the course of viral hepatitis A in childhood

The course of acute hepatitis A (AHA) in childhood is most often benign. There are relatively few reports of gallbladder involvement during such infection and its consequences. We discuss the cases of 75 children (mean age = 4.5 years) with confirmed AHA. Clinical and laboratory evaluation upon admission were classical for AHA. Only two children had normal bilirubin levels and 38.7% had visible involvement of the gallbladder with wall thickening of >3 mm, while six met criteria for acute acalculous cholecystitis. There appears to be no clear relationship between thickening of the gallbladder wall and transaminase levels, but a significant relationship with total and direct bilirubin levels (P < 0.05). Ultrasonographic examination should therefore be carried out in each case of AHA and follow-up should be performed with greater caution, if there are changes in the gallbladder wall.

Investigation of Salmonella enteritidis outbreak in four kindergartens

In June 2018, in the city of Sofia, Bulgaria, 40 children from four different kindergartens suffered from salmonellosis caused by S. enteritidis. They were reported to have consumed food prepared and delivered by a private catering service. The patients had fever, diarrhea, and some had vomiting and abdominal pain. Sixteen of them were treated in hospital, and the other 24 received home treatment. Some of the outpatients received antibiotic treatment despite WHO recommendations. All 40 isolates were positive for O: D, H: gm and H: m, and were confirmed to be Salmonella enteritidis, respectively. Using conventional and molecular methods, such as serotyping, Multiplex-PCR and PFGE, it was confirmed that the strains were epidemiologically related. Based on molecular genetic methods, we established that the epidemic outbreak had a common origin: contaminated food delivered by a private catering service, which was consumed at all four kindergartens.

Screening Library Evolution through Automation of Solution Preparation

The quality of the compound library is a critical success factor in every high-throughput screening campaign. Screening solutions have to be prepared with a high level of process control to ensure the correct identity and initial concentration of each compound. However, even under optimized storage conditions, a certain level of degradation in solution cannot be avoided. Therefore, regular quality control and eventual removal of solutions from the screening deck is necessary. Because solution preparation, especially the weighing of compounds, is a tedious and often manual task, a regular resolubilization of compounds is difficult to achieve. By complete automation of the solution preparation, the authors have laid the foundation for a life cycle management of screening solutions. They demonstrate how a combination of quality and process control leads to a continuous improvement of the screening library. In presenting an automation concept, they show how a series of innovative process optimizations led to a high-performance system that achieves full industrialization of solution preparation. ( Journal of Biomolecular Screening 2007:724-732)

Friction between a viscoelastic body and a rigid surface with random self-affine roughness

In this Letter, we study the friction between a one-dimensional elastomer and a one-dimensional rigid body having a randomly rough surface. The elastomer is modeled as a simple Kelvin body and the surface as self-affine fractal having a Hurst exponent H in the range from 0 to 1. The resulting frictional force as a function of velocity always shows a typical structure: it first increases linearly, achieves a plateau and finally drops to another constant level. The coefficient of friction on the plateau depends only weakly on the normal force. At lower velocities, the coefficient of friction depends on two dimensionless combinations of normal force, sliding velocity, shear modulus, viscosity, rms roughness, rms surface gradient, the linear size of the system, and the Hurst exponent. We discuss the physical nature of different regions of the law of friction and suggest an analytical relation describing the coefficient of friction in a wide range of loading conditions. An important implication of the analytical result is the extension of the well-known "master curve procedure" to the dependencies on the normal force and the size of the system.

Molecular Diversity Management Strategies for Building and Enhancement of Diverse and Focused Lead Discovery Compound Screening Collections

This publication describes processes for the selection of chemical compounds for the building of a high-throughput screening (HTS) collection for drug discovery, using the currently implemented process in the Discovery Technologies Unit of the Novartis Institute for Biomedical Research, Basel Switzerland as reference. More generally, the currently existing compound acquisition models and practices are discussed. Our informatics, chemistry and biology-driven compound selection consists of two steps: 1) The individual compounds are filtered and grouped into three priority classes on the basis of their individual structural properties. Substructure filters are used to eliminate or penalize compounds based on unwanted structural properties. The similarity of the structures to reference ligands of the main proven druggable target families is computed, and drug-similar compounds are prioritized for the following diversity analysis. 2) The compounds are compared to the archive compounds and a diversity analysis is performed. This is done separately for the prioritized, regular and penalized compounds with increasingly stringent dissimilarity criterion. The process includes collecting vendor catalogues and monitoring the availability of samples together with the selection and purchase decision points. The development of a corporate vendor catalogue database is described. In addition to the selection methods on a per single molecule basis, selection criteria for scaffold and combinatorial chemistry projects in collaboration with compound vendors are discussed.

Is histoaspartic protease a serine protease with a pepsin-like fold?

The primary structure of the so-called histoaspartic protease from Plasmodium falciparum has a very high percentage of identity and homology with the pepsin-like enzyme plasmepsin II. A homology modeling approach was used to calculate the three-dimensional structure of the enzyme. Molecular dynamics (MD) simulations were applied to find those structural properties of the histoaspartic protease that had a tendency to remain stable during all runs. The results have shown that hydrogen-bonded residues Ser37-His34-Asp214 are arranged without any strain, in a manner that resembles the active site of a serine protease, while Ser38 and Asn39 take up positions appropriate to formation of an oxyanion hole. Although there are several important differences between the enzyme and plasmepsin II, all of the structural features associated with a typical pepsin-like aspartic protease are present in the final model of the histoaspartic protease. A possibility that this enzyme may function as a serine protease is discussed.

Retroperitoneal malignant schwannoma and peritoneal malignant mesothelioma: a case report

Malignant schwannoma and peritoneal malignant mesothelioma (MM) are very rare tumors. Schwannoma or neurilemmoma-benign or malignant-do not arise from the nerves, but from the supporting Schwann cells. Malignant peripheral nerve sheath tumors (MPNSTs) commonly are large in size. They are painful and may cause many different symptoms depending on their location and size. MM arises primarily from the surface serosal cells of the pleural, peritoneal, and pericardial cavities. A malignant schwannoma was diagnosed in a 52-yearold woman, which was surgically treated. After a 17-month disease-free interval, local recurrence was diagnosed. The patient was operated on for second time and MM was diagnosed as second primary tumor, along with recurrence of the malignant schwannoma. The patient received postoperative adjuvant external beam radiotherapy and chemotherapy. Despite combined-modality treatment the disease progressed and the patient was operated on for third time 2.5 years after the first operation with partial tumor resection. She died 3 years after the first diagnosis. Early diagnosis of these two types of tumors is very difficult because of unspecific clinical symptoms. Singlemodality therapy of these tumors has shown poor results. Combined-modality approaches have shown some benefits, but further studies are required.

[Surgical treatment of large intestines obstruction caused by colorectal cancer]

Large intestinal obstruction like a life-threatening steatement is a subject of investigation in the present study. In such prospection are included 65 patients undergone surgery for large intestinal obstruction of cancer in period of seven years. Analyzed are after undertaken surgical procedures. It is clear that tendency of more security after surgery is concerned with the principles of radicalization after lower morbidity and mortality.

Changes in left ventricular morphology and function in end-stage dilated cardiomyopathy after reductive annuloplasty of double mitral and tricuspid orifices

BACKGROUND AND AIM

The aim of this study is to show the changes in left ventricular morphology and function after reductive annuloplasty of double mitral and tricuspid orifices (RADO) in ischemic dilated cardiomyopathy (IDCM) and primary dilated cardiomyopathy (PDCM) analyzed by intraoperative transesophageal echocardiography (TEE).

METHODS

There were 274 patients, mean age 50.1 years, 188 operated due to IDCM with ejection fraction under 30%, and 86 patients due to PDCM. Mitral annuloplasty according to A. Carpentier and our own procedure was done in 49 and 225 patients, respectively. In 265 cases (97%) our modified De Vega's tricuspid annuloplasty was performed.

RESULTS

CONCLUSION

RADO significantly changes left ventricular morphology, reverses remodeling of the heart, decreases sphericity of the left heart, improves hemodynamic function of both ventricles, and slows down progression of cardiac failure. We recommend RADO in the early stage of PDCM, immediately after the first decompensation, and as an important associated procedure in IDCM.

[Not Available]

Following a brief historical review of the populations inhabiting the Bulgarian lands, the archaeological documents, related to the rearing of children, are discussed. The various objects discovered date back mainly to the time of the slavesystem period. Some of the dishes for feeding children are also described (such as gutus, strainders, pots), clothing and ornaments, toys (ponny-carts, terracota-animals) and other objects found in children's tombs. Finally, a report is made on the special workshops, established throughout the country, for the manufacturing of toys for children.

Processing of N-linked oligosaccharide depends on its location in the anion exchanger, AE1, membrane glycoprotein

The human erythrocyte anion exchanger (AE)1 (Band 3) contains a single complex N-linked oligosaccharide that is attached to Asn(642) in the fourth extracellular loop of this polytopic membrane protein, while other isoforms (AE2, AE3 and trout AE1) are N-glycosylated on the preceding extracellular loop. Human AE1 expressed in transfected human embryonic kidney (HEK)-293 or COS-7 cells contained a high-mannose oligosaccharide. The lack of oligosaccharide processing was not due to retention of AE1 in the endoplasmic reticulum since biotinylation assays showed that approx. 30% of the protein was expressed at the cell surface. Moving the N-glycosylation site to the preceding extracellular loop in an AE1 glycosylation mutant (N555) resulted in processing of the oligosaccharide and production of a complex form of AE1. A double N-glycosylation mutant (N555/N642) contained both a high-mannose and a complex oligosaccharide chain. The complex form of the N555 mutant could be biotinylated showing that this form of the glycoprotein was at the cell surface. Pulse-chase experiments showed that the N555 mutant was efficiently converted from a high-mannose to a complex oligosaccharide with a half-time of approx. 4 h, which reflected the time course of trafficking of AE1 from the endoplasmic reticulum to the plasma membrane. The turnover of the complex form of the N555 mutant occurred with a half-life of approx. 15 h. The results show that the oligosaccharide attached to the endogenous site in extracellular loop 4 in human AE1 is not processed in HEK-293 or COS-7 cells, while the oligosaccharide attached to the preceding loop is converted into the complex form.

Resolution of glycoproteins by a lectin gel-shift assay

Gel-shift assays previously described in the literature are based on protein-protein or protein-DNA interactions. We show that carbohydrate-lectin interactions can be successfully used to alter the electrophoretic mobility of glycosylated, but not nonglycosylated, protein species in SDS-polyacrylamide gels. We were able to separate the two closely migrating mono- (95 kDa) and nonglycosylated (92 kDa) forms of a polytopic membrane protein, anion exchanger 1 (AE1), synthesized by cell-free translation or in transfected HEK293 cells. Concanavalin A was selected as the lectin due to the high mannose content of the oligosaccharide chain on AE1. Concanavalin A was either added to the samples prior to loading or copolymerized in a top layer of the separating gel, the latter being the method of choice. The presence of concanavalin A resulted in slower mobility of the monoglycosylated protein while the mobility of the nonglycosylated form was not altered. The shift in mobility was dependent on concentration of concanavalin A and the length of separating gel containing copolymerized concanavalin A. When a diglycosylated mutant of AE1 was tested, good separation was achieved at lower concentrations of concanavalin A. This lectin gel-shift assay allows the separation of N-glycosylated and nonglycosylated forms of the protein.

Calnexin interaction with N-glycosylation mutants of a polytopic membrane glycoprotein, the human erythrocyte anion exchanger 1 (band 3)

The interaction of the endoplasmic reticulum chaperone calnexin with N-glycosylation mutants of a polytopic membrane glycoprotein, the human erythrocyte anion exchanger (AE1), was characterized by cell-free translation and in transfected HEK293 cells, followed by co-immunoprecipitation using anti-calnexin antibody. AE1 contains 12-14 transmembrane segments and has a single site of N-glycosylation at Asn-642 in the fourth extracytosolic loop. This site was mutated (N642D) to create a nonglycosylated protein. Calnexin showed a preferential interaction with N-glycosylated AE1 relative to nonglycosylated AE1 both in vitro and in vivo. This interaction could be blocked by inhibition of glucosidases I and II with castanospermine. Calnexin had access to novel N-glycosylated sites created in other extracytosolic loops in AE1 by site-directed or insertional mutagenesis. The interaction with AE1 was enhanced when multiple sites were introduced into the same loop or into two different loops. An association of calnexin with truncated versions of N-glycosylated AE1 was detected after release of the nascent chains from ribosomes with puromycin. The results show that the interaction of calnexin with the polytopic membrane glycoprotein AE1 was dependent on the presence but not the location of the oligosaccharide. Furthermore, calnexin was associated with AE1 after release of AE1 from the translocation machinery.

Transmembrane folding of the human erythrocyte anion exchanger (AE1, Band 3) determined by scanning and insertional N-glycosylation mutagenesis

The human erythrocyte anion exchanger (AE1, Band 3) contains up to 14 transmembrane segments, with a single site of N-glycosylation at Asn642 in extracellular (EC) loop 4. Scanning and insertional N-glycosylation mutagenesis were used to determine the folding pattern of AE1 in the membrane. Full-length AE1, when expressed in transfected human embryonic kidney (HEK)-293 or COS-7 cells, retained a high-mannose oligosaccharide structure. Scanning N-glycosylation mutagenesis of EC loop 4 showed that N-glycosylation acceptor sites (Asn-Xaa-Ser/Thr) spaced 12 residues from the ends of adjacent transmembrane segments could be N-glycosylated. An acceptor site introduced at position 743 in intracellular (IC) loop 5 that could be N-glycosylated in a cell-free translation system was not N-glycosylated in transfected cells. Mutations designed to disrupt the folding of this loop enhanced the level of N-glycosylation at Asn743 in vitro. The results suggest that this loop might be transiently exposed to the lumen of the endoplasmic reticulum during biosynthesis but normally folds rapidly, precluding N-glycosylation. EC loop 4 insertions into positions 428, 484, 754 and 854 in EC loops 1, 2, 6 and 7 respectively were efficiently N-glycosylated, showing that these regions were extracellular. EC loop 4 insertions into positions 731 or 785 were poorly N-glycosylated, which was inconsistent with an extracellular disposition for these regions of AE1. Insertion of EC loop 4 into positions 599 and 820 in IC loops 3 and 6 respectively were not N-glycosylated in cells, which was consistent with a cytosolic disposition for these loops. Inhibitor-affinity chromatography with 4-acetamido-4'-isothiocyanostilbene-2,2'-disulphonate (SITS)-Affi-Gel was used to assess whether the AE1 mutants were in a native state. Mutants with insertions at positions 428, 484, 599, 731 and 785 showed impaired inhibitor binding, whereas insertions at positions 754, 820 and 854 retained binding. The results indicate that the folding of the C-terminal region of AE1 is more complex than originally proposed and that this region of the transporter might have a dynamic aspect.

Mapping the ends of transmembrane segments in a polytopic membrane protein. Scanning N-glycosylation mutagenesis of extracytosolic loops in the anion exchanger, band 3

Band 3, the anion exchanger of human erythrocytes, contains up to 14 transmembrane (TM) segments and has a single endogenous site of N-glycosylation at Asn642 in extracellular (EC) loop 4. The requirements for N-glycosylation of EC loops and the topology of this polytopic membrane protein were determined by scanning N-glycosylation mutagenesis and cell-free translation in a reticulocyte lysate supplemented with microsomal membranes. The endogenous and novel acceptor sites located near the middle of the 35 residue EC loop 4 were efficiently N-glycosylated; however, no N-glycosylation occurred at sites located within sharply defined regions close to the adjacent TM segments. Acceptor sites located in the center of EC loop 3, which contains 25 residues, were poorly N-glycosylated. Expansion of this loop with a 4-residue insert containing an acceptor site increased N-glycosylation. Acceptor sites located in short (<10 residues) loops (putative EC loops 1, 2, 6, and 7) were not N-glycosylated; however, insertion of EC loop 4 into EC loops 1, 2, or 7, but not 6, resulted in efficient N-glycosylation. Acceptor sites in putative intracellular (IC) loop 5 exhibited a similar pattern of N-glycosylation as EC loop 4, indicating a lumenal disposition during biosynthesis. To be efficiently N-glycosylated, EC loops in polytopic membrane proteins must be larger than 25 residues in size, with acceptor sites located greater than 12 residues away from the preceding TM segment and greater than 14 residues away from the following TM segment. Application of this requirement allowed a significant refinement of the topology of Band 3 including a more accurate mapping of the ends of TM segments. The strict distance dependence for N-glycosylation of loops suggests that TM segments in polytopic membrane proteins are held quite precisely within the translocation machinery during the N-glycosylation process.

[The use of a rapid infusion system in orthopedics]

Major orthopedic surgery such as partial resection of the pelvis and subsequent implantation of a prosthesis is highly connected with massive bleeding. Therefore we tested the hypothesis that the use of a rapid infusion device, which was originally designed for liver transplantations, can prevent hypovolemic shock. We studied 20 patients: in one group (n = 10) the iv volume was given in a conventional way (37 degrees C) by use of pressure infusion bags. Patients of the second group (n = 10) received the iv volume via the Rapid Infusion system (Haemonetics Corp., Braintree, MA). We can conclude that with this new device for rapid volume replacement it is possible to keep the patient's vital functions stable even during times of excessive bleeding and to prevent from metabolic consequences following hypovolemic shock.

[Wounds from modern small arms and international humanitarian law]

The article cites the concept, basic standards and principles of international humane law concerning the banning or restriction of some types of conventional weapons. The authors describe international methods for appreciation of destructive effects of wounding missiles. On the basis of literature and their own experiments the authors make a conclusion that actually it would be impossible to formulate a straight definition between "human" and "inhumane" bullets, as well as to establish a criterion which could determine the admissible or inadmissible limits for gunshot injuries.

[Intensification and effectiveness of scientific research in hygiene (several problems of information supply)]

The nature of the concept "intensification" and the notions effect and effectiveness, associated with it are discussed. The nature of the separate kinds effect, obtained in hygienic science are determined - primary (health) and secondary (derivative). Effectiveness is determined on that base - as juxtaposition of the kinds of effects obtained with the resources spent in the field of hygienic science. Studies were carried out on the increased intensity of utilization of information resources as factor for the improvement of effectiveness in hygienic science. The place and role of information - retrieval systems are determined. Numerous concrete information systems are discussed as well as some of the factors in the evaluation of their effectiveness.