Sensitivity of clinical strains of Neisseria gonorrhoeae circulating in Yekaterinburg and the Sverdlovsk region

The paper presents the results of determination of sensitivity of 154 gonococcal strains isolated from the patients, who were treated at the clinic of the Urals Research Institute of Dermatovenereology and Immunopathology and the Sverdlovsk Regional and Yekaterinburg City Dermatovenereological Dispensaries in 2001-2003, to penicillin, tetracycline, ciprofloxacin, ceftriaxone, spectinomycin, sparfloxacin, and moxifloxacin. It also shows the preponderance of moderately penicillin-resistant gonococci (75.3%) and their trend towards their transformation to resistant strains, tetracycline-resistant (74.0%), ciprofloxacin-sensitive (89%), and ceftriaxone-sensitive (82.5%) strains, as well as the absence of Neisseria gonorrhoeae resistant to spectinomycin, sparfloxacin, and moxifloxacin.     

Chemotherapy of glioblastoma in rats using doxorubicin-loaded nanoparticles

Glioblastomas belong to the most aggressive human cancers with short survival times. Due to the blood-brain barrier, they are mostly inaccessible to traditional chemotherapy. We have recently shown that doxorubicin bound to polysorbate-coated nanoparticles crossed the intact blood-brain barrier, thus reaching therapeutic concentrations in the brain. Here, we investigated the therapeutic potential of this formulation of doxorubicin in vivo using an animal model created by implantation of 101/8 glioblastoma tumor in rat brains. Groups of 5-8 glioblastoma-bearing rats (total n = 151) were subjected to 3 cycles of 1.5-2.5 mg/kg body weight of doxorubicin in different formulations, including doxorubicin bound to polysorbate-coated nanoparticles. The animals were analyzed for survival (% median increase of survival time, Kaplan-Meier). Preliminary histology including immunocytochemistry (glial fibrillary acidic protein, ezrin, proliferation and apoptosis) was also performed. Rats treated with doxorubicin bound to polysorbate-coated nanoparticles had significantly higher survival times compared with all other groups. Over 20% of the animals in this group showed a long-term remission. Preliminary histology confirmed lower tumor sizes and lower values for proliferation and apoptosis in this group. All groups of animals treated with polysorbate-containing formulations also had a slight inflammatory reaction to the tumor. There was no indication of neurotoxicity. Additionally, binding to nanoparticles may reduce the systemic toxicity of doxorubicin. This study showed that therapy with doxorubicin bound to nanoparticles offers a therapeutic potential for the treatment of human glioblastoma.     

Ten-year outcomes of lymphogranulomatosis treatment according to the protocol MOPP-ABVD+radiotherapy

AIM: To analyse overall recurrence-free survival of lymphogranulomatosis (LGM) patients given polychemotherapy (PCT) MOPP (mustargen-caryolisin, vincristine, natulan, prednisolone) - ABVD (adriamycin, bleomycin, vinblastin, dacarbasin) in combination with radiotherapy (RT) for 10 years. MATERIAL AND METHODS: The trial included 211 LGM patients admitted to Hematological Research Center in 1990-1996 from other hospitals without random selection. The patients were examined by the standard program including biopsy of the affected organ or lymph node, bilateral trephine biopsy. Splenectomy was performed in 17 patients, 83 patients received PCT in other hospitals, 128 untreated patients received MOPP-ABVD therapy (3 courses of MOPP and 3 courses of ABVD). Forty one patients had defects in PCT, 16 of them rejected PCT and RT. The latter was performed 4 weeks after the 6th course, contraceptives were not prescribed to women. At LGM stage II-III RT was performed by the subradical program (no radiation to ilioinguinal lymph nodes) in doses 40-44 Gy on the foci and 32-36 Gy preventively, on massive and residual foci after PCT - 5-10 Gy additionally. RESULTS: Ten-year overall and recurrence-free survival in the untreated group reached 83 and 80%, respectively, for pretreated patients - 46 and 36%, respectively. Causes of death of 26 patients were LGM progression, infection (tuberculosis, as a rule), secondary tumors and acute myeloblastic leukemia (AML). After remission 25 women gave birth to a healthy child and 12 healthy children were born to 9 males. CONCLUSION: MOPP-ABVD plus radiotherapy program according to subradical and radical variants was in the past effective but invalidating rescue therapy. Present-day programs consider the histological variant, stage and prognostic factors allowing an individual therapeutic approach with step-by-step reduction of RT in the treatment of LGM patients. Involvement of the bone marrow in primary patients had no influence on the treatment results. This refers this affection not to a generalized stage IV, but to stage III along with involvement of the lymph nodes and the spleen.     

Toxicological studies of doxorubicin bound to polysorbate 80-coated poly(butyl cyanoacrylate) nanoparticles in healthy rats and rats with intracranial glioblastoma.

Polysorbate 80-coated poly(butyl cyanoacrylate) nanoparticles (NP) were shown to enable the transport of a number of drugs including the anti-tumour antibiotic doxorubicin (DOX) across the blood-brain barrier (BBB) to the brain after intravenous administration and to considerably reduce the growth of brain tumours in rats. The objective of the present study was to evaluate the acute toxicity of DOX associated with polysorbate 80-coated NP in healthy rats and to establish a therapeutic dose range for this formulation in rats with intracranially implanted 101/8 glioblastoma. Single intravenous administration of empty poly(butyl cyanoacrylate) NP in the dose range 100-400 mg/kg did not cause mortality within the period of observation. NP also did not affect body weight or weight of internal organs. Association of DOX with poly(butyl cyanoacrylate) NP did not produce significant changes of quantitative parameters of acute toxicity of the anti-tumour agent. Likewise, the presence of polysorbate 80 in the formulations was not associated with changes in toxicity compared with free or nanoparticulate drug. Dose regimen of 3x1.5 mg/kg on days 2, 5, 8 after tumour implantation did not cause drug-induced mortality. The results in tumour-bearing rats were similar to those in healthy rats. These results demonstrate that the toxicity of DOX bound to NP was similar or even lower than that of free DOX.     

Inhibition of cell migration by PITENINs: the role of ARF6

We have reported previously the development of small-molecule phosphatidylinositol-3,4,5-trisphosphate (PIP3) antagonists (PITs) that block pleckstrin homology (PH) domain interaction, including activation of Akt, and show anti-tumor potential. Here we show that the same molecules inhibit growth factor-induced actin remodeling, lamellipodia formation and, ultimately, cell migration and invasion, consistent with an important role of PIP3 in these processes. In vivo, a PIT-1 analog displays significant inhibition on tumor angiogenesis and metastasis. ADP ribosylation factor 6 (ARF6) was recently identified as an important mediator of cytoskeleton and cell motility, which is regulated by PIP3-dependent membrane translocation of the guanine nucleotide exchange factors (GEFs), such as ADP-ribosylation factor nucleotide binding site opener (ARNO) and general receptor for 3-phosphoinositides (GRP1). We demonstrate that PITs inhibit PIP3/ARNO or GRP1 PH domain binding and membrane localization, resulting in the inhibition of ARF6 activation. Importantly, we show that expression of the constitutively active mutant of ARF6 attenuates inhibition of lamellipodia formation and cell migration by PITs, confirming that inhibition of ARF6 contributes to inhibition of these processes by PITs. Overall, our studies demonstrate the feasibility of developing specific small-molecule targeting PIP3 binding by PH domains as potential anticancer agents that can simultaneously interfere with cancer development at multiple points.     

Significant Transport of Doxorubicin into the Brain with Polysorbate 80-Coated Nanoparticles

Purpose. To investigate the possibility of delivering of anticancer drugs into the brain using colloidal carriers (nanoparticles). Methods. Rats obtained 5 mg/kg of doxorubicin by i v. injection in form of 4 preparations : 1. a simple solution in saline, 2. a simple solution in polysorbate 80 1% in saline, 3. bound to poly (butyl cyanoacrylate) nanoparticles, and 4. bound to poly(butyl cyanoacrylate) nanoparticles overcoated with 1% polysorbate 80 (Tween^® 80). After sacrifice of the animals after 10 min, 1, 2, 4, 6, and 8 hours, the doxorubicin concentrations in plasma, liver, spleen, lungs, kidneys, heart and brain were determined after extraction by HPLC. Results. No significant difference in the body distribution was observed between the two solution formulations. The two nanoparticle formulations very significantly decreased the heart concentrations. High brain concentrations of doxorubicin (>6 g/g) were achieved with the nanoparticles overcoated with polysorbate 80 between 2 and 4 hours. The brain concentrations observed with the other three preparations were always below the detection limit (< 0.1 |g/g). Conclusions. The present study demonstrates that the brain concentration of systemically administered doxorubicin can be enhanced over 60-fold by binding to biodegradable poly(butyl cyanoacrylate) nanoparticles, overcoated with the nonionic surfactant polysorbate 80. It is highly probable that coated particles reached the brain intact and released the drug after endocytosis by the brain blood vessel endothelial cells.     

Open population comparative randomized clinical trial of lavomax efficacy and safety in combined treatment of non-gonococcal urethritis

A total of 40 patients with non-gonococcal urethritis (NGU) were divided into two groups. Twenty patients of group 1 received standard antibacterial treatment while 20 patients of group 2 received the same treatment plus an immunotropic drug based on tiloron (lavomax) in a course dose 1.25 g. Patients of group 2 had no recurrences while in group 1 recurrences were seen in 25% patients. Addition of lavomax resulted in clinical and etiological cure and activation of local (secretory IgA) and systemic (interferons alpha and gamma in blood serum) factors in anti-infection defense in NGU patients.     

Photodynamic therapy of experimental B-16 melanoma in mice with tumor-targeted 5,10,15,20-tetraphenylporphin-loaded PEG-PE micelles

Polyethylene glycol (PEG)-diacyl lipid micelles have been prepared by loading with the hydrophobic meso-5,10,15,20-tetraphenyl-21H,23H-porphine (TPP) and used for the photodynamic treatment of B-16 melanoma cells in vitro and in vivo. The use of PEG-PE micelles allowed for a 150-fold increased the solubilization of TPP, compared with the native drug. The average size of the PEG-PE micelles was in the range of 10–12 nm with a narrow size distribution. At 50 μg/ml of TPP in micelles with an irradiation intensity of 4.5–21.5 mW/cm², the viability of B-16 melanoma cells in vitro decreased in a fluence-dependent manner. A highly effective outcome of photodynamic therapy (PDT) with TPP-loaded PEG-PE micelles can be further increased by modifying such micelles with cancer-specific monoclonal antibody 2C5 to TPP-loaded micelles to tumor cells. TPP-containing 2C5-modified micelles provided the strongest phototoxic effect against B-16 cells in vitro compared with TPP-loaded plain micelles at the same TPP concentration. The association of TPP-loaded immuno-targeted micelles with melanoma cells was also studied by flow cytometry. An increase in cell association was found for 2C5-targeted micelles compared with non-targeted micelles. In vivo, the PDT treatment of subcutaneous melanoma-bearing C57BL/6 mice with 100 mW/cm² of 630 nm laser light 9 h after the administration of the micellar TPP (1 mg/kg of TPP) resulted in a significant inhibition of tumor growth. Compared with controls, the weight of postmortem tumors was approx. 3.5- and 7.5-fold smaller with TPP-loaded PEG-PE micelles and TPP-loaded PEG-PE 2C5-immunomicelles, respectively.     

Small molecule inhibition of phosphatidylinositol-3,4,5-triphosphate (PIP3) binding to pleckstrin homology domains

The PI3-kinase (PI3K) pathway regulates many cellular processes, especially cell metabolism, cell survival, and apoptosis. Phosphatidylinositol-3,4,5-trisphosphate (PIP3), the product of PI3K activity and a key signaling molecule, acts by recruiting pleckstrin-homology (PH) domain-containing proteins to cell membranes. Here, we describe a new structural class of nonphosphoinositide small molecule antagonists (PITenins, PITs) of PIP3-PH domain interactions (IC(50) ranges from 13.4 to 31 μM in PIP3/Akt PH domain binding assay). PITs inhibit interactions of a number of PIP3-binding PH domains, including those of Akt and PDK1, without affecting several PIP2-selective PH domains. As a result, PITs suppress the PI3K-PDK1-Akt pathway and trigger metabolic stress and apoptosis. A PIT-1 analog displayed significant antitumor activity in vivo, including inhibition of tumor growth and induction of apoptosis. Overall, our studies demonstrate the feasibility of developing specific small molecule antagonists of PIP3 signaling.