Humanized Mouse Model of HIV Infection.

The development of new drugs for the treatment of HIV infection requires testing of their efficacy in a relevant animal model, such as humanized mice, which, unfortunately, are not yet available in Russia. In the present study, we have developed conditions for the humanization of immunodeficient NSG mice with human hematopoietic stem cells. Humanized animals generated during the study showed a high degree of chimerism and harbored repopulation of the entire range of human lymphocytes required for HIV replication in the blood and organs. Inoculation of these mice with HIV-1 virus led to stable viremia, which was confirmed by the presence of viral RNA in blood plasma throughout the entire period of observation and proviral DNA in the organs of animals 4 weeks after HIV infection.

[Endovascular embolization for prevention of recurrent bleeding from the upper gastrointestinal tract]. / Opyt primeneniya endovaskulyarnoi embolizatsii dlya profilaktiki retsidiva krovotecheniya iz verkhnikh otdelov zheludochno-kishechnogo trakta.

OBJECTIVE: To evaluate the results of preventive endovascular hemostasis in patients with high risk of recurrent bleeding from the upper gastrointestinal tract. MATERIAL AND METHODS: We analyzed treatment outcomes in 158 patients with ulcerative gastroduodenal bleeding and high risk of recurrence (≥17 scores), Forrest 1-2 A/B and mortality (SAPS II score ≥30). Endovascular embolization of the left gastric or gastroduodenal artery was performed to prevent recurrent bleeding. RESULTS: Endovascular hemostasis was technically successful in 94.4% of cases (153 patients). Embolization could not be performed due to technical reasons in 5 patients. One patient developed retroperitoneal hematoma as a complication after transcatheter angiography and embolization that required surgical intervention. Recurrent bleeding after technically successful embolization occurred in 11 (7%) patients. The PVA microemboli and spirals were used for embolization of the left gastric and gastroduodenal arteries, respectively. Additional PVA microemboli were also used in gastroduodenal artery in some cases. Twenty-six (16.5%) patients died. CONCLUSION: Endovascular hemostasis in patients with severe comorbidities (SAPS II score ≥30) and high risk of recurrent bleeding (≥17 scores) reduced the incidence of recurrent bleeding to 6.96% and mortality to 17%.

Preclinical Study of Therapeutic Efficacy of a New Russian Radiopharmaceutical 177Lu-DOTA-PSMA.

The therapeutic efficacy of a Russian radiopharmaceutical 177Lu-DOTA-PSMA was studied in vivo using male BALB/c nu/nu (nude) mice with prostate carcinoma 22Rv1 xenografts by tumor growth inhibition criterion. The mean tumor volumes in mice treated with 177Lu-DOTA-PSMA were significantly lower than in animals of the control group. There were no significant differences in the values of tumor growth inhibition between the groups of animals receiving 3.7 or 7.4 MBq of 177Lu-DOTA-PSMA.

[Hybrid interventions for tandem occlusions in acute phase of ischemic stroke]. / Gibridnye vmeshatel'stva pri lechenii tandemnykh okklyuzii v ostreishei faze ishemicheskogo insul'ta.

OBJECTIVE: To evaluate the effectiveness of hybrid interventions, i.e. endovascular mechanical thrombectomy from intracranial arteries combined with open thrombectomy or carotid endarterectomy from extracranial internal carotid artery. MATERIAL AND METHODS: We analyzed 16 patients who underwent mechanical thrombectomy/thrombaspiration combined with open surgery between January 2014 and March 2021. All patients had occlusion of extracranial and intracranial segments internal carotid artery or initial segments of the middle cerebral artery. Baseline data, diagnostic algorithm, timing and results of treatment were analyzed. Study endpoints were technical success of revascularization, clinically significant hemorrhagic transformation, NIHSS and modified Rankin score of neurological impairment, as well as outcome of disease within 90 days. RESULTS: We restored patency of ICA and intracranial arteries in 13 out of 16 patients. In 9 patients, we obtained a positive effect with significant regression of neurological symptoms (mRS <2). In 3 patients, severe neurological deficit persisted throughout the entire follow-up period. Four patients died. Thus, effectiveness of technique was 56.2% (t=3), mortality rate was 25% (t=2.3). There was a relationship between the timing of interventions and outcomes of disease. Indeed, all dead and most of disabled patients underwent surgery later than 6 hours from the onset of disease. CONCLUSION: Hybrid interventions for tandem occlusions of carotid arteries can significantly increase efficiency and accelerate recanalization of great extracranial vessels in patients with tandem lesions in acute phase of ischemic stroke. Moreover, hybrid interventions significantly reduce the cost of reperfusion procedure. In case of severe atherosclerotic stenosis, simultaneous open endarterectomy from common and internal carotid arteries has a significant advantage over stenting due to no need for antithrombotic therapy.

Generation of SARS-CoV-2 Mouse Model by Transient Expression of the Human ACE2 Gene Mediated by Intranasal Administration of AAV-hACE2.

One of the most important steps in the development of drugs and vaccines against a new coronavirus infection is their testing on a relevant animal model. The laboratory mouse, with well-studied immunology, is the preferred mammalian model in experimental medicine. However, mice are not susceptible to infection with SARS-CoV-2 due to the lack of human angiotensin-converting enzyme (hACE2), which is the cell receptor of SARS-CoV-2 and necessary for the entry of the virus into the cell. In present work, it was shown that intranasal administration of the adeno-associated vectors AAV9 and AAV-DJ encoding the hACE2 provided a high level of expression of ACE2 gene in the lungs of mice. In contrast, the introduction of the AAV6 vector led to a low level ACE2 expression. Infection with SARS-CoV-2 of mice expressing hACE2 in the lungs led to virus replication and development of bronchopneumonia on the 7th day after infection. Thus, a simple method for delivering the human ACE2 gene to mouse lungs by intranasal administration of the AAV vector has been proposed. This approach enabled rapid generation of mouse model for studying coronavirus infection.

[Generation of SARS-CoV-2 Mouse Model by Transient Expression of the Human ACE2 Gene Mediated by Intranasal Administration of AAV-hACE2].

One of the most important steps in the development of drugs and vaccines against a new coronavirus infection is their testing on a relevant animal model. The laboratory mouse, with well-studied immunology, is the preferred mammalian model in experimental medicine. However, mice are not susceptible to infection with SARS-CoV-2 due to the lack of human angiotensin-converting enzyme (hACE2), which is the cell receptor of SARS-CoV-2 and necessary for the entry of the virus into the cell. In present work, it was shown that intranasal administration of the adeno-associated vectors AAV9 and AAV-DJ encoding the hACE2 provided a high level of expression of ACE2 gene in the lungs of mice. In contrast, the introduction of the AAV6 vector led to a low level ACE2 expression. Infection with SARS-CoV-2 of mice expressing hACE2 in the lungs led to virus replication and development of bronchopneumonia on the 7th day after infection. Thus, a simple method for delivering the human ACE2 gene to mouse lungs by intranasal administration of the AAV vector has been proposed. This approach enabled rapid generation of mouse model for studying coronavirus infection.

[CT angiography and endovascular treatment in acute mesenteric ischemia]. / KT-angiografiya i endovaskulyarnye vmeshatel'stva pri ostroi mezenterial'noi ishemii ­ pervye rezul'taty.

OBJECTIVE: To optimize the treatment strategy for acute mesenteric ischemia (AMI). MATERIAL AND METHODS: The study included 43 patients aged 76.4±10.3 years. CT angiography and endovascular repair of mesenteric vessels underlie the new treatment approach. RESULTS: CT angiography according to the established criteria was performed in 31 patients with suspected AMI throughout 1 year. Sensitivity was 90.0%, specificity - 100%, accuracy - 95%. Endovascular interventions were applied in 13 patients (successful in 8 cases and unsuccessful in 5 patients). Mortality rate was 37.5%. Fifteen patients with clinical signs of peritonitis or after previous unsuccessful interventional revascularization underwent open surgery. Mortality rate was 86.7%. CONCLUSION: CT angiography is valuable to diagnose AMI at the stage of reversible changes in bowel wall in some cases. Endovascular revascularization as the first-line treatment has certain prospects.

Cytostatic Activity of Combretastatin A-4 Derivatives in an In Vitro System.

Cytostatic activity of combretastatin A-4, its 11 analogues, and paclitaxel (Taxacad) was evaluated in vitro on human tumor cells A549 (lung adenocarcinoma) and PC-3 (prostate adenocarcinoma) in order to find the active and stable compound as a promising antitumor agent. 5-(4-Methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-isoxazole (compound 123124) and 3-(3,4,5-trimethoxyphenyl)-4-(4-methoxyphenyl)-isoxazole (compound 29310186) demonstrated the highest cytostatic activity (IC50≈8×10-9 М). The activity of two other cytotoxic compounds (2E)-1-(7-methoxy-2H-1,3-benzodioxol-5-yl)-3-(4-methoxyphenyl)prop-2-en-1-one (compound 104815) and 4-(3-amino-4-methoxyphenyl)-5-(3,4,5-trimethoxyphenyl)-1H-pyrazole hydrochloride (compound 198732) was close to that of Taxacad: IC50 65×10-9 and 80×10-9 М, respectively, and are also promising active components for the development of antitumor drugs.

Specific Cytotoxicity of Targeted 177Lu and 212Pb-Based Radiopharmaceuticals.

Two radiopharmaceutical preparations were developed on the basis of artificial targeted polypeptide ZHER2 specific to HER2/neu tumor marker and radionuclides 177Lu (ZHER2-HSA-chelator-177Lu) or 212Pb (ZHER2-HSA-chelator-212Pb). The objective was to evaluate in vitro the cytotoxic activity of the targeted radiopharmaceuticals using two cultured human breast cancer cell lines with different expression of HER2/neu: SK-BR3 (high expression of HER2/neu) and MCF-7 (low expression of HER2/neu). It was shown that the cytotoxic effect of both preparations was significantly higher against the SK-BR-3 cells. The cytotoxicity correlated with the incubation period (it was higher after 72 h than after 24 h) and was significantly more pronounced in comparison with activity of radionuclide salts without a specific ligand. In vivo preclinical study of these pharmaceuticals seems to be very promising in animals with xenografted tumors showing high expression of HER2/neu marker.

Quantitative Assessment of the Socioeconomic Potential of Advanced Development Territories of Regions of the Far Eastern Federal District.

The article provides a quantitative assessment of the socioeconomic potential of the territories of advanced development (TAD) of the regions of the Far Eastern Federal District (FEFD). The key indicators of the TAD of the Far Eastern Federal District are considered, their contribution to the dynamics of investments in fixed assets and employment of the regions of the Far Eastern Federal District is determined, groups of regions of the Far Eastern Federal District are identified according to the degree of influence of the TAD on the parameters of social, economic and investment development, the industry specialization of the TAD is analyzed, the contribution of the TAD to investment and employment is assessed in the economy of the Far Eastern Federal District until 2024.

[Is acute mesenteric ischemia incurable situation? The current state of the problem]. / Ostraya mezenterial'naya ishemiya ­ inkurabel'naya situatsiya? Sovremennoe sostoyanie problemy.

Mortality rates in acute mesenteric ischemia remain at an extremely high level for many decades. Early diagnosis and selection of the optimal method of revascularization are among the ways to optimize tactics. The diagnostic study of choice is CT angiography. Its active and systemic use can help to detect ischemia at the reversible stage. The article examines in detail the indications for the application of this diagnostic study. The question of preference for the revascularization method remains debatable. The arguments of proponents of open and endovascular interventions on mesenteric vessels are presented. Other, still unresolved tactical issues are also considered, such as indications for re-operations and application of the principles of damage control tactics.

Preclinical Study of Pharmacological Properties of Doxorubicin-NPh.

Preclinical study of therapeutic properties of an innovative drug Doxorubicin-NPh (doxorubicin in the form of ultrafine suspension of phospholipid liposomes) in comparison with free doxorubicin (Doxorubicin-Teva) and protected doxorubicin (Caelyx) was performed on transplanted murine tumor models. All these drugs were efficient in Ca755 breast carcinoma model (tumor growth inhibition ≈100%, increase in lifespan 90.6-114.3%). In P388 lymphocytic leukemia and LLC lung carcinoma, advantages of the protected doxorubicin by the benefit/risk ratio (width of therapeutic interval) were demonstrated: Caelyx>Doxorubicin-NPh>Doxorubicin-Teva. Doxorubicin-NPh and Caelyx exhibited similar therapeutic activity in the LLC model, especially when administered 3 times with 3-day intervals; for Doxorubicin-Teva, the optimal interval between the injections was 7 days.

[Chlorine e6 in phospholipid nanoparticles with specific targeting and penetrating peptides as prospective composition for photodynamic therapy of malignant neoplasms]. / Khlorin e6 v fosfolipidnykh nanochastitsakh so spetsificheskimi adresnymi i pronikaiushchimi peptidami kak perspektivnaia kompozitsiia dlia fotodinamicheskoi terapii zlokachestvennykh novoobrazovanii.

Cytotoxic and photoinduced activity of chlorine e6 (Ce6) in phospholipid nanoparticles with specific tumor targeting and cell-penetrating peptides was studied in vitro using human fibrosarcoma cells HT-1080. It was shown, that the binding of cell-penetrating peptide R7 - alone or combined with the peptide containing specific targeting motif NGR (Asn-Gly-Arg) - resulted in 3-fold decrease of Ce6 photoinduced activity as compared with that in nanoparticles without peptides (IC50 values were 0.7 µg/ml and 2.1 µg/ml, respectively). The NGR influence was unexpectedly low - less than 20% (IC50 1.7 µg/ml). This suggests the more importance of Ce6 cell penetration in this case, than of NGR-mediated targeting. The effect of inclusion of both peptides on the total cytotoxicity of Ce6 was minimal (10-16 times less than on the specific photoinduced activity). The obtained results - together with earlier shown effects on improvement of the pharmacokinetics of Ce6 in vivo after its embedding into phospholipid nanoparticles - indicate the prospects of using the obtained phospholipid nanoparticles system for photodynamic therapy.

The Antitumor Efficacy of a Complex Based on Two-Vector System for Coexpression of the Suicide Gene Fcu1 and Cre Recombinase.

In this study, we evaluated the antitumor activity of a gene therapy complex in which the tumor-specific control of the expression of the effector suicide gene FCU1 was performed using a two-vector system based on the site-specific Cre-LoxP recombinase system. The complex of interest showed a high therapeutic potential in a mouse colon adenocarcinoma model.

[Opportunities of endovideosurgical interventions in thoracic and abdominal trauma].

AIM: To analyze the results of laparo- and thoracoscopy in patients with thoracic and abdominal trauma in conditions of emergency hospital. MATERIAL AND METHODS: For the period 2006-2013 we performed 56 laparoscopic and 15 thoracoscopic interventions in 67 patients with trauma. There were 80.6% of men and 19.4% of women aged 35±1.7 years. Abdominal, thoracic and thoraco-abdominal injuries were observed in 51 (76.1%), 14 (20.9%) and 2 (3%) patients. Abdominal or thoracic trauma alone was diagnosed in 41 (61.2%) cases and combined injury - in 26 (38.8%) patients. 37 (66%) interventions were performed laparoscopically. Conversion to laparotomy was observed in 19 (34%) cases. Mean volume of hemoperitoneum was 458 ml (range 100-1100 ml). In 11 (73.3%) patients thoracoscopic surgery was performed and conversion of access was applied in 4 (26.7%) cases. RESULTS: No injuries of internal organs were observed in 19.6% and 13.3% of patients using laparo- and thoracoscopy respectively. So inadvisable open surgery was prevented although formal indications for laparo- and thoracotomy were present. In 25% and 20% of abdominal and thoracic damages respectively we avoided relatively unjustified laparo- or thoracotomy because of injuries were cured endoscopically. No one missed injury was observed. Postoperative complications were diagnosed in 5.6% of cases. Mortality rate was 15.6% in case of severe combined trauma. Mean hospital stay was 23.2 days (range 3-105). CONCLUSION: Endoscopic techniques are perspective in treatment of thoracic and abdominal trauma. It allows to avoid inadvisable laparo- and thoracotomy in some cases and to improve results of treatment.

Study of photoinduced antitumor activity of phthalocyanin-based nanostructures as pro-photosensitizers in photodynamic therapy of malignant tumors in vivo.

Nanoparticles of aluminum and zinc phthalocyanin and metal-free phthalocyanin (AlPc, ZnPc, and H2Pc), whose molecular forms are photosensitizers, can serve as effective "prophotosensitizers" in photodynamic therapy for malignant tumors. Transition (stimulation) of photo-inert nanoparticles into a photoactive photosensitizer is realized locally in the tumor node by its exposure to potent laser pulses. Systemic injection of AlPc, ZnPc, and H2Pc nanoparticles has not led to accumulation of their photoactive form in the skin, which can lead to the development of skin phototoxicity. Effective protocols of photodynamic therapy with ZnPc nanoparticles are determined. The use of these protocols in mice with S-37 sarcoma led to 92-70% tumor growth inhibition, 48% improvement of survival, and cure in 84% cases.

[Experimental foundation of using intraoperative endopelvic cisplatin with hyperthermia for rectal cancer].

Previously, significant increase in survival in locally-advanced rectal cancer as a result of heated intraoperative intraperitoneal chemotherapy was reported. Our study used cisplatin 0.5 mg/ml (0.05 per cent solution) in the culture of pharyngeal epidermoid carcinoma (PEC) cells (HEP-2) and A-549 culture of lung carcinoma cells. The number of viable cells was estimated colorimetrically after 24 and 48 hr incubation. 50%-rise in inhibition of culture growth was assumed to be biologically significant. Forty-eight hours after inoculation, single dose of cisplatin 8 mg/kg was injected in mice bearing transplanted lung carcinoma of Lewis (LLC). That was followed by death of tumor cells. Preheating (45 deg. C, 1 hr) did not influence either the cytostatic or therapeutic effect of cisplatin in vivo.That procedure inhibited tumor growth by 7-8% and the effect did not wear off until day 11 or longer. Survival in LLC-bearing mice rose by 26% which pointed to the advantages offered by heated cytostatic chemotherapy.

[Antitumor immunotherapy with the use of synthetic fragments of survivin].

The endogenous protein survivin is present in tumor cells and inhibits apoptosis. The influence of vaccination of mice by survivin fragments on growth of various types of tumors was studied to examine the possibility of creation of an antitumor vaccinating agent on its basis. Two peptides corresponding to the (118-144) and (80-88)-(153-165) sequences of survivin 2B were chosen and synthesized on the basis of literature data and theoretical calculations. Their ability to stimulate antibody production in mice of the C57BL/6J line (b haplotype) and in BDF1 hybrids (b x d haplotype) was investigated. Both peptides were shown to stimulate production of antibodies that bound the recombinant survivin in the BDF1 mice. Immunization of the BDF1 and C57BL/6J mice with the recombinant survivin resulted in the formation of antibodies that reacted with the (118-144) peptide. The effect of preventive vaccination with the peptides and the recombinant protein on the dynamics of growth of several species of tumors was studied. Vaccination with the (80-88)-(153-165) peptide was found to cause an antitumor effect in BDF1 mice suffering from sarcoma S-37. Thus, the creation of an antitumor agent on the basis of this peptide is a promising area of further studies.