[Staged treatment of a patient with malignant ischemic cerebral infarction]. / Sluchai etapnogo lecheniya patsienta so zlokachestvennym ishemicheskim infarktom mozga.

The authors discuss surgical decompression of the brain in patients with malignant ischemic cerebral infarcts. Successful staged treatment of a middle-aged patient with malignant ischemic stroke in the middle cerebral artery basin is presented.

[Osteoprotective effect of bread enriched with protein, dietary fiber, calcium, iron and iodine in hypoestrogen-induced osteoporosis among rats].

The search for new strategies for the prevention and control of osteoporosis is an urgent task. Functional foodstuffs and their components are of particular interest in this regard. The aim was to study the effect of bread enriched with protein, dietary fiber, calcium, iron and iodine on the state of the bone tissue of rats in a model of postmenopausal osteoporosis. Material and methods. The experiment was performed on sexually mature female Wistar rats divided into groups: K - control (sham-operated rats, not ovariectomized); О30 - osteoporosis model (animals were sacrificed 30 days after ovariectomy); groups О120 and О120+ - a model of osteoporosis (rats were sacrificed 120 days after ovariectomy). All animals were fed a standard vivary diet. For rats of the О120+ group, from the 40th to the 120th day, enriched bread was included in the diet in an amount of 6 g per 100 g of body weight per day. The bread was fortified with protein (whey protein, blood plasma proteins from farm animals), dietary fiber, calcium (eggshell), iron (purified hemoglobin) and iodized whey protein. Animals of groups K and О120 received unfortified bread in the same amount. Blood levels of total calcium (by colorimetric method), gonadotropins, testosterone, and estradiol (by enzyme-linked immunosorbent assay) were analyzed. Microtomographic evaluation of the architecture and mineral density of the trabecular part of the femur and lumbar vertebrae was performed. Histomorphological analysis of the uterus and femur of animals was performed. Results and discussion. In animals of the О120+ group, in comparison with the О120 sample, there was a decrease in blood testosterone and a marked compensatory release of follicle-stimulating hormone, while no changes were detected in the concentration of estradiol and the state of the uterus atrophied against the background of ovariectomy. There was an increase in the trabecular mineral density of the femur and lumbar vertebrae. The proportion of bone trabeculae in the total volume of the femoral metaphysis (BV/TV) in animals of the О120+ sample was 12.5±0.66% compared to 10.4±0.52% in the О120 group. The values of the structural model index (SMI) reflecting the loss of bone strength and the trabecularity coefficient (TbPf) in О120+ rats (1.44±0.07 and 5.96±0.29 1/mm) were significantly lower than these parameters in the О120 group (1.74±0.08; 9.13±0.46 1/mm, р<0.05). The micro-architectural structure of the femur in the О120+ group of rats was close to that of the О30 sample, which serves as a model of the early stage of osteoporosis (SMI 1.42±0.07; TbPf 5.55±0.28 1/mm). The percentage of bone resorption perimeter and the number of osteoclasts in the О120+ femoral trabeculae were lower than in the О120 group. In the О120+ group, active osteoblasts were observed in a significant part of the resorption cavities. Cell differentiation more was observed in the osteogenic direction than in the adipogenic direction. Conclusion. Bread enriched with protein, fiber, calcium, iron and iodine, effectively weakens osteoporosis induced by ovariectomy in rats. Its inclusion in the diet may be beneficial for the prevention and treatment of systemic postmenopausal osteoporosis.

[The influence of the drying method for food properties and hypolidemic potential of oyster mushrooms (Pleurotus ostreatus)].

The aim of this research was to study the influence of two drying methods: freeze-drying sublimation and dry-air drying on the selected nutritional properties and hypolipidemic potential of fruiting bodies of oyster mushroom (Pleurotus ostreatus). The criteria for evaluation of the food properties were the color, the morphological structure, regidratation capacity, the total level of soluble proteins, fats, polysaccharides, free amino acids and monosaccharides. Lipid-lowering potential of oyster mushroom was evaluated by the concentration of lovastatin and the level of antioxidant activity. It has been experimentally revealed that the value of optical density of hydro-alcohol extracts of dried oyster mushrooms at a wavelength of 295 nm most clearly characterized its color which intensity was almost twice less in sublimated mushrooms, than шт the sample dried by dry-air method. Histological data showed that dry-air drying lead to the destruction of the mushroom cells and to the formation of a dense layered structure. Sublimation drying preserved the ordered cell structure and provided less deformation and shrinkage of the tissues. Using X-ray microtomography it was reported that freeze-dried mushrooms had uniform pore volume distribution. Dry-air dehydration method lead to the formation of larger cavities. The average percentage of the open pores was: 29.41±0.52% (after dry-air method), 11.10±0.41% (after freeze-drying method). Respectively the number of closed pores, which reflected the true value of porosity, was 0.99±0.01 and 1.75±0.01%. Structural differences of the samples of the dry oyster mushroom combined with their unequal hydration ability. Indicator of rehydration for oyster mushroom dried by sublimation method was 5.4±0.1, and for samples obtained by dry-air method it was 3.2±0.1. Respectively the average time of maximum water absorption was 22.7±1.8 and 45.3±2.9 minutes. It was found that the freeze-drying sublimation conditions were more conducive for the preservation of the biologically active protein and polysaccharide components of oyster mushrooms and on the other hand dry-air drying method increased the nutritional value of oyster mushrooms due to the reactions of polysaccharides autohydrolysis. The number of proteins and polysaccharides of the Oyster mushrooms samples dried by dry-air method and freeze-drying method was 72.0% and 56.0% respectively. Concentrations of free amino acids and glucose in the samples dried by freeze-drying and dry-air methods were 11.60±0.31%; 175.20±6.10 mg% and 7.00±0.28%; 144.0±5.7 mg% respectively. It has been experimentally recorded that the conditions of freeze drying were optimal in terms of ensuring the preservation of the content of natural statin and the antioxidant capacity of oyster mushrooms that provided its hypolipidemic potential. The amount of lovastatin in an the freeze-dried samples was 342±9.0 mg/kg, and was significantly higher than in the samples received by dry-air method - 190±6.0 mg/kg. The level of antioxidant activity of the oyster mushrooms samples were respectively 3.83±0.02 against 2.0±0.03 mmol/100 g. The conducted researches proved that for the production of dry oyster mushroom as a potential biologically active feedstock for the functional food products with lipid-regulating directivity the choice of the drying method had a fundamental importance.

[Multicenter experience of using Fortelyzin during staged reperfusion therapy of acute ischemic stroke in anterior circulation]. / Opyt mnogotsentrovogo primeneniya preparata Fortelizin pri provedenii etapnoi reperfuzionnoi terapii ostrogo ishemicheskogo insul'ta v karotidnoi sisteme.

OBJECTIVE: To evaluate the safety and efficacy of Fortelyzin in the performance of staged reperfusion therapy for acute ischemic stroke (intravenous thrombolytic therapy plus mechanical thrombectomy) in anterior circulation within the FORTA RF multicenter pilot study. MATERIAL AND METHODS: The study included 72 patients with acute ischemic stroke in anterior circulation, who underwent staged reperfusion therapy in four vascular centers of the Russian Federation from December 2019 to January 2023. RESULTS: The mean time from illness onset to hospitalization was 94.5 minutes in the Fortelyzin group and 97.2 min in the Actilyse group (p=0.78). The time from the moment of hospitalization to the admission of the patient to the X-ray operating room was significantly lower in the Fortelyzin group (p=0.002). The incidence of symptomatic hemorrhagic transformations in the Fortelyzin group was 6%, in the Actilyse group - 8% (p=0.75). A favorable functional outcome in the first group was observed in 47% of patients, in the control group in 42% (p=0.66). Mortality in both groups did not differ significantly and amounted to 22% and 25%, respectively. CONCLUSION: The first results of the FORTA RF multicenter study demonstrate the safety and efficacy of Fortelyzin in staged reperfusion therapy compared to Actilyse.

[Pathogenetic and clinical features of cerebral venous thrombosis]. / Patogeneticheskie i klinicheskie osobennosti tserebral'nykh venoznykh trombozov.

OBJECTIVE: To study the etiopathogenetic and clinical features of inpatients with venous thrombosis. MATERIAL AND METHODS: The analysis of 25 medical cases of patients with venous thrombosis was performed. RESULTS: Cerebral venous thrombosis most often developed in females (88%), the average age was 36 years. The most frequent localization of thrombosis was observed in the transverse sinus, as independently (40%) and in combination with thrombosis of other sinuses. Headache was the main clinical sign that could be a single feature or accompanied by other neurological symptoms. In 13 patients (86.6%), multiple polymorphisms in blood coagulation genes (more than 4 mutations) were identified. All patients were prescribed anticoagulant therapy. In all cases, there were positive dynamics of the patients' condition, in the form of a decrease in the intensity of headache or complete regression of cephalalgia, neurological symptoms regressed in 20 patients (80%), there was no fatal outcome. CONCLUSION: If central venous thrombosis is detected, especially in young people, an analysis for genetic polymorphism of the blood coagulation system and the folate cycle should be carried out. This will allow timely development of secondary prevention and reduce the risk of recurrent thrombosis.

Clinical and Pathogenetic Significance of Amylase Level and Microtomographic Index of Synovial Fluid in Various Joint Lesions.

The aim of the investigation was to study the level of amylolytic activity and microtomographic index of synovial fluid density as well as to substantiate their clinical and pathogenetic significance by identifying correlations with the known informative indicators reflecting characteristic features of the pathological process in various joint diseases. Materials and Methods: Samples of synovial fluid from 95 patients with various joint pathologies at the stage of the disease progression characterized by copious effusion into articular cavities have been examined. Synovial fluid samples obtained by knee arthrocentesis served as a material for the investigation. Conventional methods were used to determine the concentration of uric acid, inorganic phosphorus, total protein, and amylolytic activity level in the selected samples while X-ray density was identified by computed microtomography. Results: All samples of pathological joint fluid have shown a high level of amylolytic activity as compared to the synovial fluid from healthy joints. The relationship between the level of amylolytic activity in synovia and specific joint pathology has been identified. It has also been found that uric acid values, inorganic phosphorus concentrations, and total protein in various types of joint damage may influence X-ray density of the synovial fluid. Correlations between the studied indices have been established. Conclusion: New data on the level of synovia amylolytic activity has been obtained in one non-inflammatory and six different inflammatory diseases. Pathogenically determined correlation between the microtomographic index of synovial fluid density and concentrations of uric acid, inorganic phosphorus, total protein has been confirmed. Specific indicators of X-ray density of synovia in various joint pathologies as well as unidirectional and multidirectional data in comparison with the norm allow us to consider X-ray microtomography as a method that reveals additional details during investigation of synovial fluid density and brings new surrogate markers for the study of pathogenetic mechanisms of the development, differentiation, and treatment of various joint pathologies.

[Nonimmunogenic staphylokinase in the treatment of acute ischemic stroke (FRIDA trial results)]. / Neimmunogennaya stafilokinaza ­ novyi tromboliticheskii preparat v lechenii ishemicheskogo insul'ta (rezul'taty issledovaniya FRIDA).

AIM OF THE STUDY: To investigate the efficacy and safety of non-immunogenic staphylokinase (NS) compared with alteplase (A) in patients with acute ischemic stroke (AIS) within 4.5 h after symptom onset. MATERIAL AND METHODS: 336 patients with IS within 4.5 h after symptom onset were included in a randomized, open-label, multicenter, parallel-group, non-inferiority comparative trial of NS vs A (168 patients in each group). NS was administered as an intravenous bolus in a dose of 10 mg, regardless of body weight, over 10 s, A was administered as a bolus infusion in a dose of 0.9 mg/kg, maximum 90 mg over 1 hour. The primary efficacy endpoint was a favorable outcome, defined as a modified Rankin scale (mRS) score of 0-1 on day 90. Safety endpoints included all-cause mortality on day 90, symptomatic intracranial haemorrhage, and other serious adverse events (SAEs). RESULTS: At day 90, 84 (50%) patients reached the primary endpoint (mRS 0-1) in the NS group, 68 (41%) patients - in the A group (p=0.10, OR=1.47, 95% CI=0.93-2.32). The difference between groups NS and A was 9.5% (95% CI= -1.7-20.7) and the lower limit of the 95% CI did not cross the margin of non-inferiority (pnon-inferiority<0.0001). There were no significant differences in the frequency of deaths between the groups: on day 90, 17 (10%) patients in the NS group and 24 (14%) in the A group had died (p=0.32). There was a trend towards significant differences in the frequency of symptomatic intracranial haemorrhage: NS group - 5 (3%) patients, A group - 13 (8%) patients (p=0.087, OR=0.37, 95% CI=0.1-1.13). There were significant differences in the number of patients with SAEs: in the NS group - 22 (13%) patients, in the A group - 37 (22%) patients (p=0.044, OR=0.53, 95% CI=0.28-0.98). CONCLUSION: The presented results of the FRIDA trial are the first in the world to use a drug based on NS in patients with IS. It has been shown that a single bolus (within 10 s) administration of NS at a standard dose of 10 mg, regardless of body weight, allows to conduct fast, effective and safe thrombolytic therapy in patients with IS within 4.5 h after symptom onset. In further clinical tials of NS, it is planned to expand the therapeutic window beyond 4.5 h after symptom onset in patients with IS.

Disruption of splicing regulated by a CUG-binding protein in myotonic dystrophy.

Myotonic dystrophy (DM) is caused by a CTG expansion in the 3' untranslated region of the DM gene. One model of DM pathogenesis suggests that RNAs from the expanded allele create a gain-of-function mutation by the inappropriate binding of proteins to the CUG repeats. Data presented here indicate that the conserved heterogeneous nuclear ribonucleoprotein, CUG-binding protein (CUG-BP), may mediate the trans-dominant effect of the RNA. CUG-BP was found to bind to the human cardiac troponin T (cTNT) pre-messenger RNA and regulate its alternative splicing. Splicing of cTNT was disrupted in DM striated muscle and in normal cells expressing transcripts that contain CUG repeats. Altered expression of genes regulated posttranscriptionally by CUG-BP therefore may contribute to DM pathogenesis.

[Efficacy, tolerability and safety of the treatment with teberif: the results of a 2-year randomized clinical trial of treatment naïve patients with remitting multiple sclerosis, who have not received DMT, after switching from other interferon ß-1a]. / Éffektivnost', perenosimost' i bezopasnost' terapii preparatom teberif: rezul'taty dvukhletnego klinicheskogo issledovaniia u patsientov s remittiruiushchim rasseiannym sklerozom, ranee ne poluchavshikh PITRS, i pri perekliuchenii s drugogo interferona ß-1a.

OBJECTIVES: To evaluate efficacy, safety, and tolerability of the treatment with teberif/interferon ß-1a, to analyze safety, tolerability and dynamics of key efficacy variables after switching from referent drug rebif to biosimilar teberif in patients with remitting multiple sclerosis (RMS). MATERIAL AND METHODS: During the main period of the international multicenter randomized study patients were randomized to receive treatment with teberif for 52 weeks, or rebif for 52 weeks, or placebo for 16 weeks to evaluate efficacy and safety of treatment. After the main study period, patients were group-independently switched to take open-label teberif treatment during the next 48 weeks. RESULTS AND CONCLUSION: The analysis of multiple evaluation parameters of the efficiency during the 1st study period (blinded) and the 2nd study period (open-label) has shown that teberif and rebif demonstrate equivalent efficacy and stable 2-year efficacy of teberif was proven. There were no significant differences between teberif and rebif for all safety, and tolerability parameters. Switching from rebif to teberif didn't influence treatment efficacy. The 2-year study results confirmed a biosimilar teberif's benign tolerability and expected safety profile to other interferons ß-1a in patients with RMS.

Molecular basis for impaired muscle differentiation in myotonic dystrophy.

Differentiation of skeletal muscle is affected in myotonic dystrophy (DM) patients. Analysis of cultured myoblasts from DM patients shows that DM myoblasts lose the capability to withdraw from the cell cycle during differentiation. Our data demonstrate that the expression and activity of the proteins responsible for cell cycle withdrawal are altered in DM muscle cells. Skeletal muscle cells from DM patients fail to induce cytoplasmic levels of a CUG RNA binding protein, CUGBP1, while normal differentiated cells accumulate CUGBP1 in the cytoplasm. In cells from normal patients, CUGBP1 up-regulates p21 protein during differentiation. Several lines of evidence show that CUGBP1 induces the translation of p21 via binding to a GC-rich sequence located within the 5' region of p21 mRNA. Failure of DM cells to accumulate CUGBP1 in the cytoplasm leads to a significant reduction of p21 and to alterations of other proteins responsible for the cell cycle withdrawal. The activity of cdk4 declines during differentiation of cells from control patients, while in DM cells cdk4 is highly active during all stages of differentiation. In addition, DM cells do not form Rb/E2F repressor complexes that are abundant in differentiated cells from normal patients. Our data provide evidence for an impaired cell cycle withdrawal in DM muscle cells and suggest that alterations in the activity of CUGBP1 causes disruption of p21-dependent control of cell cycle arrest.

CUG repeat binding protein (CUGBP1) interacts with the 5' region of C/EBPbeta mRNA and regulates translation of C/EBPbeta isoforms.

The transcription factor CCAAT/enhancer binding protein beta, C/EBPbeta, plays a significant role in the regulation of hepatocyte growth and differentiation. A single mRNA coding for C/EBPbeta produces several protein isoforms. Two pathways for generation of low molecular weight C/EBPbeta isoforms have been described: specific proteolytic cleavage and initiation of translation from different AUG codons of C/EBPbeta mRNA. A truncated C/EBPbeta isoform, LIP, is induced in rat livers in response to partial hepatectomy (PH) via the alternative translation mechanism. Here we present evidence that CUG repeat binding protein, CUGBP1, interacts with the 5' region of C/EBPbeta mRNA and regulates translation of C/EBPbeta isoforms. Two binding sites for CUGBP1 are located side by side between the first and second AUG codons of C/EBPbeta mRNA. One binding site is observed in an out of frame short open reading frame (sORF) that has been previously shown to regulate initiation of translation from different AUG codons of C/EBPbeta mRNA. Analysis of cytoplasmic and polysomal proteins from rat liver after PH showed that CUGBP1 is associated with polysomes that translate low molecular weight isoforms of C/EBPbeta. The binding activity of CUGBP1 to the 5' region of C/EBPbeta mRNA shows increased association with these polysomal fractions after PH. Addition of CUGBP1 into a cell-free translation system leads to increased translation of low molecular weight isoforms of C/EBPbeta. Our data demonstrate that CUGBP1 protein is an important component for the regulation of initiation from different AUG codons of C/EBPbeta mRNA.

[Increased expression of genes coding for replication proteins during the period of DNA synthesis]. / Povyshennaia ékspressiia genov, kodiruiushchikh belki replikatsii, v period sinteza DNK.

Individual mRNA coding for proteins of the alpha-polymerase complex were isolated from replicating hepatocytes. cDNAs were synthesized by reverse transcriptase. Three clones were identified by colony hybridization of the S period cDNA library. The sequences of these clones were complementary to the investigated mRNAs. Two clones named pr12 and pr167 revealed increased expressions in the S period. The level of mRNA pr127 does not change during liver regeneration. The amount of pr127 mRNA was about 1% of the total mRNA population. pr12, pr127 and pr167 mRNAs were isolated by the hybrid-selection method and were translated in a cell-free system. The products of translation were analysed by "activity" gel. It was shown that pr167 mRNA coded for protein 140 kDa with DNA polymerase activity. pr12 protein is an unknown component of the alpha-polymerase complex. We suggested that this protein participates in the initiation of DNA replication.

[Identification and characteristics of mRNA's showing increased levels during DNA replication]. / Identifikatsiia i kharakteristika mRNK, soderzhanie kotorykh povysheno v period replikatsii DNK.

A library of double-stranded cDNA was prepared using poly (A) + RNA from regenerating rat liver 20 h after partial hepatectomy. Differential screening of 350 recombinant clones with cDNA-G0 and cDNA-S identified eleven cDNA clones (pRL), the sequences of which were preferentially expressed during the DNA replication period. Levels of mRNAs complementary to these clones were 2--10-fold higher in the S-period, than in G0. Using plasmid cDNAs to different mRNA, pRL we have investigated the changes in the levels of mRNA pRL during liver regeneration. The level of mRNA mRL2 and pRL79 was increased just before DNA replication. mRNA pRL35 accumulates after partial hepatectomy with the maximum at 6 h. The augment of two other mRNA concentrations was expressed to a lesser extent. Northern-blot analysis allowed to determine the individual dual mRNAs corresponding to each of the three clones with their sizes ranging from about 1650 to 3900 bases. Three mRNAs (pRL35, 67 and 79) were shown (by hybrid-selected translation) to code for proteins of about 100, 140 and 120 kDa, respectively.

[Characteristics of DNA isolated from a complex form of DNA-polymerase alpha from the rat liver]. / Kharakteristika DNK, vydellennoi iz kompleksnoi formy DNK-polimerazyalpha pecheni krysy.

A complex from of DNA polymerase alpha was isolated from the nuclear membrane of hepatocytes. DNA fragments were shown to be among components of the complex under study. In this paper we present evidence that DNA from the alpha-polymerase complex from quiescent hepatocytes (DNA-G) differs in its nucleotide composition from its counterpart (DNA-S) isolated from hepatocytes synthesizing DNA. As judged by dot hybridization, DNA-G0 does not contain nucleotide sequences which are complementary to ribosomal or messenger RNA, whereas the abovementioned sequences are present in DNA-S. At the same time DNA-G0 is found to contain sequences which are homologous to both SV40 DNA and yeast TRPI-ARS1 DNA. The difference in nucleotide sequences between DNA-G0 and DNA-S indicates that in the process of replication DNA is being stretched across the multienzyme complex located on the nuclear membrane.

[Transferrin mRNA from the rat liver]. / mRNK transferrins iz pecheni krysy.

Highly purified transferrin mRNA was isolated from rat liver using indirect immunoprecipitation of polysomes with antibodies to rat transferrin and poly(U)-sepharose chromatography. Isolated transferrin mRNA was apparently homogeneous in sedimentation and electrophoretic experiments. Its sedimentation coefficient is 20S and molecular weight 925 000 (chain length 2800 nucleotides). The purified mRNA programmed the synthesis of electrophoretically homogeneous precursor of transferrin. The cell-free translation of transferrin mRNA was highly sensitive to the inhibition by cap analogues (pm7G) that seems being indicative of the capped structure of its 5' end. Hybridization of transferrin mRNA with [3H]poly(U) revealed the discrete length distribution of poly(A) sequences in mRNA (96, 45 and 26 mononucleotides). The proportion of double-stranded (nuclease SI-resistant) regions in transferrin mRNA is as high as 50-60%. Transferrin cDNA was synthesized via the reverse transcription of transferrin mRNA with oligo(dT) primer. This cDNA hydridized with mRNA template and with total polysomal RNA at C0t1/2 values 1.5 X 10(-3) and 3.6 X 10(0) mol nucleotides X 1(-1) Xs, respectively. Hence, the purified mRNA preparation is 2500-fold enriched with transferrin-coding sequences in comparison to the total polysomal RNA from rat liver.

[Cloning of double-stranded DNA--a transcript of rat transferrin mRNA]. / Klonirovanie dvunitevoi DNK--transkripta mRNK transferrina krysy.

Two-stage synthesis of double-stranded DNA was performed using purified rat transferrin mRNA as a template, reverse transcriptase and DNA polymerase I. Double-stranded transcripts of transferrin mRNA were cloned as recombinant plasmid derivatives of pBR322. The insert length in these plasmids varied from 150 to 1500 bp. Clones carrying transferrin mRNA sequences were identified using colony hybridization and Southern blot hybridization with 32P-cDNA probe. Nick-translated DNAs from transformed clones hybridized with a single component of rat liver polysomal RNA that corresponded to transferrin mRNA in its molecular weight (0.86 MD). In hybridization selection cell-free translation test cloned plasmid DNAs hybridized specifically with rat liver poly(A) +RNA that programmed the cell-free synthesis of a polypeptide identical to pretransferrin in antigenic properties and molecular weight.

[Comparative analysis of recombinant bacteriophages containing the sequences of the chromosomal ceruloplasmin gene in the rat]. / Sravnitel'nyi analiz rekombinantnykh bakteriofagov, soderzhashchikh posledovatel'nosti khromosomnogo gena tseruloplazmina krysy.

Three clones carrying the sequences of ceruloplasmin gene were isolated from the library of EcoRI fragments of rat chromosomal DNA cloned in Charon 4A vector. These clones were identified using, i) plaque hybridization with [32P] cDNA transcribed from highly purified rat ceruloplasmin (Cp) mRNA; ii) blot hybridization of the restriction fragments of recombinant DNAs with Cp cDNA and iii) hybridization selection of Cp mRNA followed by its cell-free translation. Oligo (dT)-primed cDNA transcripts of Cp mRNA having different length as well as cloned Cp cDNA isolated from rat liver cDNA library were used as hybridization probes for the study of mRNA-coding segments of Cp gene. The length of inserts in recombinant DNAs varied from 7.5 up to 12.3 megadaltons. EcoRI-fragments of Cp gene were mapped within recombinant DNA and their homology to each other was studied.

[Cloning genes, induced by x-ray irradiation in rat liver cells]. / Klonirovanie genov, indutsiruemykh rentgenovskim oblucheniem v kletkakh pecheni krysy.

The library of cDNAs synthesized on poly(A)+ mRNA derived from rat liver after total X-irradiation of animals has been obtained. cDNA-clones (p gamma clones) representing sequences inducibly transcribed as a result of radiation treatment were isolated by differential screening. The increased expression of p gamma mRNAs was observed during the period from 6 to 24 h after irradiation by 3-6 Gy dose. It was concluded that p gamma mRNAs do not code for the liver-specified proteins because these mRNAs are also present in the rat fibroblasts. We suggest that p gamma genes are involved in the pathways of DNA-repair system.

[Cloning of mRNA nucleotide sequences amplified during DNA replication in the regenerating liver]. / Klonirovanie nukleotidnykh posledovatel'nostei mRNK, soderzhanie kotorykh povysheno v period replikatsii DNK v regeneriruiushchei pecheni.

A library of double-stranded cDNA has been constructed using the mRNA of regenerating rat liver 20 hr after partial hepatectomy. The differential screening of the library with the regenerating liver specific and the resting-liver-specific single-stranded cDNA probes has identified 11 cDNA clones which sequences are preferentially expressed in regenerating rat liver. The RNA dot blot hybridization has shown that levels of RNA complementary to these clones are 3 to 8-fold higher in dividing cells as compared with resting cells.