Layer-preferential substitutions and magnetic properties of pyrrhotite-type Fe7-yMyX8 chalcogenides (X = S, Se; M = Ti, Co).

A comparative study of four series of pyrrhotite-type chalcogenide compounds Fe(7-y)M(y)X(8) (X = S, Se) with substitution of Ti or Co for iron has been performed by means of x-ray and neutron powder diffraction, and by magnetization measurements. In Fe(7-y)M(y)X(8) compounds having a ferrimagnetic order at y = 0, the substitution of either Ti or Co for iron is observed to result in a monotonous decrease of the magnetic ordering temperature, while the resultant magnetization shows a non-monotonous behavior with a minimum around y = 1.0-1.5 in all the Fe(7-y)M(y)X(8) families except Fe(7-y)Co(y)Se(8). Suppression of a magnetically ordered state with substitutions in Fe(7-y)M(y)X(8) is ascribed to nearly zero values of Ti and Co magnetic moments, while the non-monotonous changes of the resultant magnetization are explained by the compensation of the sublattice magnetizations due to the non-random substitutions in alternating metallic layers. The difference in the cation partitioning observed in Fe(7-y)Ti(y)X(8) and Fe(7-y)Co(y)X(8) is attributed to the difference in the spatial extension of Ti and Co 3d orbitals. High coercive field values (20-24 kOe) observed at low temperatures in the Ti-containing compounds Fe(7-y)Ti(y)X(8) with y ⩾ 3 are suggested to result from the enhancement of Fe orbital moment due to the Ti for Fe substitution.

[Experience with high-dose chemotherapy in patients with testicular diffuse large B-cell lymphoma].

AIM: To evaluate the efficiency of high-dose therapy according to the DLBL-CNS-2007 protocol in patients with testicular diffuse large B-cell lymphoma (DLBL). SUBJECTS AND METHODS: Out of 408 male patients with non-Hodgkin lymphoma, 8 patients aged 50 to 69 years (median age 55.5 years) with primary testicular (n=3) or with generalized-stage testicular DLBL (n=5) were included in the study. These patients were followed up at the Hematology Research Center, Ministry of Health of the Russian Federation, in 2007 to 2013. Systemic chemotherapy was performed in accordance with the DLBL-CNS-2007 protocol. RESULTS: The DLBL-CNS-2007 protocol was implemented in first-line therapy in 7 patients. At the first diagnostic stage, one patient was found to have anaplastic seminoma; in this connection right orchifuniculectomy was carried out, followed by radiotherapy applied to the scrotal region in a total focal dose of 34 Gy. This patient with disease recurrence was included in the DLBL-CNS-2007 treatment protocol. The number of polychemotherapy (PCT) cycles (n=4 or 6) was determined by the time to achieve complete remission. After completion of DLBL-CNS-2007 PCT, 6 patients achieved complete remission; the primary resistant disease was noted in 2 cases. At this moment 6 patients are alive in first complete remission during the median follow-up of 50 months (10-54 months). CONCLUSION: The findings suggest that high-dose therapy according to the DLBL-CNS-2007 protocol in patients with testicular DLBL can achieve complete remission and increase overall and event-free survival rates. This fact should be borne out by a large number of observations.

A cluster-glass magnetic state in R5Pd2 (R = Ho, Tb) compounds evidenced by AC-susceptibility and neutron scattering measurements.

AC- and DC-susceptibility, high-field magnetization and neutron diffraction measurements have been performed in order to study the magnetic state of R5Pd2 (R = Ho, Tb) compounds. The results show that both compounds undergo cluster-glass freezing upon cooling below Tf. According to the neutron diffraction a long-range magnetic order is absent down to 2 K and magnetic clusters with short-range incommensurate antiferromagnetic correlations exist not only below Tf but also in a wide temperature range above the freezing temperature (at least up to 2Tf). A complex cluster-glass magnetic state existing in Ho5Pd2 and Tb5Pd2 down to low temperatures results in rather complicated magnetization behavior in DC and AC magnetic fields. Such an unusual magnetic state in compounds with a high rare-earth concentration may be associated with the layered type of their crystal structure and with substantial atomic disorder, which results in frustrations in the magnetic subsystem.

Magnetic order, field-induced phase transitions and magnetoresistance in the intercalated compound Fe0.5TiS2.

Measurements of the magnetic susceptibility, magnetization, electrical resistivity and neutron diffraction have been performed for the compound Fe(0.5)TiS(2) in which Fe atoms are intercalated between S-Ti-S tri-layers. It has been shown that this compound with a monoclinic crystal structure exhibits an antiferromagnetic (AF) ground state below the Néel temperature T(N) ≈ 140 K. Small deviations from the stoichiometry and some disordering effects caused by the additional low-temperature heat treatment do not affect substantially the AF state in Fe(0.5)TiS(2). According to neutron diffraction data the magnetic structure at 2 K is described by the propagation vector k = (1/4,0,1/4). The Fe magnetic moments with a value of (2.9 ± 0.1) µ(B) are directed at an angle of (78.5 ± 1.8)° to the layers. Application of the magnetic field at T < T(N) induces a metamagnetic phase transition to the ferromagnetic (F) state, which is accompanied by the large magnetoresistance effect (|Δρ/ρ| up to 27%). Below 100 K, the field-induced AF-F transition is found to be irreversible, as evidenced by magnetoresistance and neutron diffraction measurements. The magnetization reversal in the metastable F state is accompanied at low temperatures by substantial hysteresis (ΔH ~ 100 kOe) which is associated with the Ising character of Fe ions.

[Diffuse large B-cell lymphoma with primary involvement of mediastinal lymph nodes: diagnosis and treatment].

AIM: To diagnose diffuse large B-cell lymphosarcoma (DLBCLS) with primary involvement of the mediastinal lymph nodes (LN) and to evaluate the efficiency of aggressive polychemotherapy (PCT). SUBJECTS AND METHODS: The study included 15 patients (6 men and 9 women aged 18 to 70 years; median 38 years) followed up at the Hematology Research Center, Russian Academy of Medical Sciences, in 2004 to 2009. Three and 12 patients had Stages II and IE DLBCLS, respectively. B symptoms were found in 14 (93.4%) patients. Increased lactate dehydrogenase (LDH) concentrations were detectable in 14 (93.4%) patients; tumors of 10 cm or more (bulky disease) were seen in 11 (73.3%). Enlarged cervical, supraclavicular, and axillary lymph nodes were found in 9 (60%) patients; lung involvement via extension in 9 (60%), and invasion into the pericardium in 5 (33.3%) and soft tissues of the anterior thoracic wall in (13.3%). There were no signs of involvement of extranodal organs at the moment of diagnosis. All the 15 patients received PCT according to the modified NHL-BFM-90 program: 4 to 6 courses depending on the response to the therapy; 10 (66.6%) and 5 (33.3%) patients had 4 and 6 courses, respectively; for consolidating purpose, 11 (78.5%) patients were prescribed radiotherapy applied to the mediastinum in a cumulative dose of 36 Gy due to the fact that they had a residual mass. RESULTS: Thirteen (86.6%) patients achieved a complete remission (CR). Primary PCT resistance was confirmed in one case. Another patient was stated to have near-complete remission. No recurrences were notified during the follow-up. The mean CR duration was 24.5 (range 2-49) months. CONCLUSION: DLBCLS with primary LN involvement is an individual nosological entity to be differentiated from primary mediastinal large B-cell lymphosarcoma. In most cases, DLBCLS shows signs of a poor prognosis, which makes it necessary to perform aggressive PCT.

[First experience of using modified program NHL-BFM-90 for the treatment of primary diffuse large-B-cell lymphosarcoma of the bones and soft tissues with poor-prognosis].

AIM: To evaluate efficacy of intensive modified program NHL-BFM-90 (mNHL-BFM-90) in adult poor-prognosis patients with diffuse large B-cell lymphosarcoma (DLBCL) of the bones and soft tissues. MATERIAL AND METHODS: The mNHL-BFM-90 program was used in the treatment of 3 male and 2 female patients aged 17-69 years (median 42 years). Four patients had DLBCL of the bones and one patient--DLBCL of the soft tissues. All the patients had tumors more than 10 cm in size. B-symptoms, a high concentration of lactate dehydrogenase (LDG) were registered in 3 patients. One patient had stage IE by Ann-Arbor, two--stage IIE (involvement of regional lymph nodes), two--stage ME (multiple bone lesions). A total of 4-6 blocks of polychemotherapy according to mNHL-BFM-90 program were performed. RESULTS: Complete remissions were achieved in all the patients. They had no recurrences after 6 to 20 month (median 13 months) follow-up. CONCLUSION: Positive results of the program mNHL-BFM-90 in poor-prognosis patients with DLBCL of the bones and tissues necessitate further studies of this therapy.

[Primary lymphoproliferative diseases of the central nervous system].

Primary CNS lymphomas have worse prognosis than other extranodal lymphomas: remissions are rare, recurrences are frequent. Literature is analysed on diagnosis, prognostic factors, perspectives and problems of treatment of primary CNS lymphomas.

[High-dose therapy of Burkitt's lymphoma in patients over 40 years of age].

AIM: To analyse efficacy and tolerance of high-dose polychemotherapy (PCT) of Berkitt's lymphoma (BL) in patients aged over 40 years. MATERIAL AND METHODS: High-dose PCT was given to 6 BL patients aged 41-56 years (median 48.1 years). RESULTS: Complete clinicohematological remissions were achieved in 4 patients. In two of them the treatment was discontinued after three blocks of PCT because of severe infectious complications. According to 4-12 month follow-up, remission continues. Remission was not achieved in two patients: one patient had primary resistance, the other died of sepsis after the second PCT course before remission. The time to remission did not correlate with age. Duration of myelotoxic agranulocytosis varied from 2 to 24 days. Duration of agranulocytosis did not correlate with age. Infections complicated 19 of 20 PCT blocks. Severity of complications caused withdrawal of three patients. CONCLUSION: BL is biologically heterogenous as it demonstrates different responses to BL-M-04 program. Causes of slow regression of tumor mass in some patients need further investigations. In spite of a great number of infectious complications high-dose therapy has no alternative.

[Efficacy of conservative treatment of gastric lymphosarcoma].

AIM: To compare efficacy and toxicity of conservative therapy (different programs of polychemotherapy) of gastric lymphosarcoma conducted for the last 10 years in Hematological Research Center of the Russian Academy of Medical Sciences. MATERIAL AND METHODS: The study included 63 patients (40 females and 23 males aged 14 to 78 years, mean age 49 years) with primary diagnosis of gastric lymphosarcoma (GL). Of them, 56 (89%) patients had diffuse large B-cell lymphosarcoma (DLBCL) and 7 (11%) had gastric Berkitt's lymphoma (BL). Only detection of t(8;14) with rearrangement of c-myc gene provided accurate diagnosis of gastric BL. By the treatment DLBCL patients were divided into two groups: 44 patients of group 1 received polychemotherapy (PCT) according to CHOP scheme or in combination with radiotherapy and surgical treatment; 12 patients of group 2 were treated according to modified program mNHL-BFM-90, without surgical or radiation treatment. Of 7 patients with gastric BL 5 patients received treatment according to a modified program mNHL-BFM-90 and 2 patients were given CHOP because of DLBCL misdiagnosis without cytogenetic detection of t(8;14). RESULTS: Overall survival in group 1 was 73% in mean follow-up 61 months. The survival depended only on initial factors of poor prognosis (PPF): tumor size over 10 cm, Ann-Arbor stage higher than IE, B-symptoms, elevated level of LDH. Overall survival of 18 gastric DLBCL patients without PPF reached 94%, of 26 patients with PPF - 60%. Lethality due to side effects was 4% (2 patients), primary resistance was 14% (6 patients), recurrence arose in 9% (4 patients). Overall survival in group 2 was 100% in mean remission duration 18 months, was unrelated to PPF (10 of 12 patients) but correlated with high toxicity. 5 BL patients treated with a modified mNHL-BFM-90 program achieved remission (a mean follow-up at present is 1 to 50 months, mean 24 months). 2 BL patients treated with CHOP died for a year. CONCLUSION: Gastric lymphosarcomas are sensitive to chemotherapy, thereby PCT only is effective in most patients. PPF in gastric DLBCL were responsible for poor outcome in 40% patients in CHOP treatment. The modified program mNHL-BFM-90 can produce up to 100% complete long-term remissions in therapy of gastric lymphosarcoma in adults both in BL and DLBCL patients. A cytogenetic examination of c-myc gene rearrangement is obligatory before initiation of PCT of gastric lymphosarcoma.

[Interaction between albumin-bound dinitrosyl iron complexes and reactive oxygen species].

It has been established that albumin-bound dinitrosyl iron complexes can be destroyed by superoxide radicals generated in a xanthine-xanthine oxidase system. It was shown that peroxynitrite also effectively destroyed albumin-bound dinitrosyl iron complexes. At the same time, hydrogen peroxide and tert-butyl hydroperoxide did not stimulate the destruction of albumin-bound dinitrosyl iron complexes up to concentrations one order higher than the content of NO. The data have been obtained indicating that dinitrosyl iron complexes possess the vasodilatory activity. It has been proposed that peroxynitrite and superoxide radical, by causing the destruction of albumin-bound dinitrosyl iron complexes, affect the physiological properties of nitric oxide.

[First experience with the modified program NHL-BFM-90 application in adult patients with primary diffuse large B-cell gastric lymphosarcoma with unfavourable prognosis].

AIM: To assess efficacy of a modified program NHL-BFM-90 in adult patients with primary diffuse large B-cell gastric lymphosarcoms (PDLBGL) with unfavourable prognosis. MATERIAL AND METHODS: Modified courses of NHL-BFM-90 were conducted in 5 patients aged 27-67 years from January 2004 to September 2005. Four patients received chemotherapy of the first line, in one patient block therapy followed monotherapy with chlorambucil and a CHOEP course. All the patients were in a severe clinical condition and had several initial factors of unfavourable prognosis: size of the tumor more than 10 cm; stage IE and more advanced; B-symptoms; proliferative activity above 70%. The program NHL-BFM-90 was modified because of the patients' age. Chemotherapy was conducted according to the middle arm of the original program NHL-BFM-90, but methotrexate was introduced in a dose 1 g/m2 for 12 hours, while leukovorin was given 18 hours after the start of methotrexate injection. In two cases the blocks were enhanced with rituximab, 2 patients had doxorubicin in block A, in one case block C was enhanced with methotrexate. A total of 23 modified blocks NHL-BFM-90 were performed: one patient was given 6 blocks, two patients--5, one patient--4 blocks and one patient--3 blocks. RESULTS: Four patients after block 2 and one patient after block 3 of polychemotherapy NHL-BFM-90 achieved remission of the disease of 6 to 22 months duration which still continues. Infectious complications related to hematological toxicity arose more frequently at the latest courses of chemotherapy. CONCLUSION: Treatment according to the modified program NHL-BFM-90 in adult patients with PDLBGL and unfavourable prognosis is highly effective. For a mean follow-up of 10.2 months no recurrences occurred. The number of courses can be reduced to decrease accumulated hematological toxicity and in case of rapid achievement of remission.

[Interaction between dinitrosyl iron complexes and intermediate products of oxidative stress].

The interaction between glutathione-containing dinitrosyl iron complexes and superoxide radicals has been studied under the conditions of superoxide radical generation in mitochondria and in a model system xanthine-xanthine oxidase. It has been shown that both superoxide radical and hydroxyl radical are involved in the destruction of dinitrosyl iron complexes. At the same time, iron contained in dinitrosyl iron complex, apparently, does not catalyze the decomposition of hydrogen peroxide with the formation of hydroxyl radical. It has been found that dinitrosyl iron complexes with different anion ligands inhibit effectively the formation of phenoxyl probucol radical in a hemin-H2O2 a system. In this process, different components of the dinitrosyl iron complexes take part in the antioxidant action of these complexes.

[A CHOP-21 course efficacy in therapy of diffuse large B-cell lymphosarcoma].

AIM: To examine efficacy of polychemotherapy (PCT) CHOP-21 in patients with diffuse large B-cell lymphosarcoma (DLBCL). MATERIAL AND METHODS: Fifty-five DLBCL patients received first-line therapy according to CHOP-21 program in 1996-2004. The diagnosis was made by WHO criteria. RESULTS: Initially, 37 patients had lymph node lesions, 18--nonlymphatic lesions. Complete remissions were achieved in 49% (56.7% in nodal lesions, 33.3% in extranodal ones). Overall 5-year survival was 35%, event-free--25%, for patients with nodal lesions--36 and 32%, respectively, extranodal lesions--35 and 22%, respectively. Overall 5-year and event-free survival in patients with local lesions was 85 and 75%, generalized--25 and 20%, respectively. In patients with involvement of the gastrointestinal tract 3-year overall and event-free survival reached 50 and 45%. Event-free survival was not seen in patients with extranodal lesions of other locations in overall 3-year survival 45%. CONCLUSION: PCT program CHOP-21 was effective in DLBCL patients with local nodular lesions except cases with large-size tumors, invasion in the adjacent organs and tissues and isolated gastric lesion.

[The interaction of ferritin and myoglobin as inductors of lipid peroxidation. The role of reactive oxygen and nitrogen species]. / Vzaimodeistvie ferritina i mioglobina kak induktorov perekisnogo okisleniia lipidov. Rol' aktivnykh form kisloroda i azota.

The effect of iron dinitrosyl complexes, S-nitrosoglutathione, and glutathione on free radical oxidation of rat heart mitochondria induced by tert-butyl hydroperoxide and metmyoglobin or their combination with ferritin was studied. It was shown that iron dinitrosyl complexes or the combination of S-nitrosoglutathione and glutathione inhibited most effectively the peroxidation of mitochondrial membranes. It was found that ferritin stimulated the prooxidant action of metmyoglobin. Using EPR spectroscopy, it was established that, in conditions of O2*- generation, the destruction of iron dinitrosyl complexes took place. Iron dinitrosyl complexes also inhibited the formation of thiyl radicals, which appeared during O2*- generation in the system containing glutathione and S-nitrosoglutathione. It is essential that the formation of iron dinitrosyl complexes in this reaction system took place with the involvement of ferritin. It was proposed that the prooxidant action of ferritin and myoglobin could be inverted to the antioxidant one.

Area under the curve of methotrexate and creatinine clearance are outcome-determining factors in primary CNS lymphomas.

Although high-dose methotrexate (HD-MTX) is the most effective drug against primary CNS lymphomas (PCNSL), outcome-determining variables related to its administration schedule have not been defined. The impact on toxicity and outcome of the area under the curve (AUC(MTX)), dose intensity (DI(MTX)) and infusion rate (IR(MTX)) of MTX and plasmatic creatinine clearance (CL(crea)) was investigated in a retrospective series of 45 PCNSL patients treated with three different HD-MTX-based combinations. Anticonvulsants were administered in 31 pts (69%). Age >60 years, anticonvulsant therapy, slow IR(MTX) (1100 micromol hl(-1) were independently associated with a better survival. Slow CL(crea) and high AUC(MTX) are favourable outcome-determining factors in PCNSL, while slow CL(crea) is significantly related to higher toxicity. AUC(MTX) significantly correlates with age, anticonvulsant therapy, IR(MTX), and DI(MTX). These findings, which seem to support the choice of an MTX dose >/=3 gm(-2) in a 4-6-h infusion, every 3-4 weeks, deserve to be assessed prospectively in future trials. MTX dose adjustments in patients with fast CL(crea) should be investigated.

[Effect of coenzyme Q10 on free radical centers in isolated rat myocardium tissue]. / Vliianie koénzima Q10 na svobodnoradikal'nye tsentry tkani izolirovannogo miokarda krysa.

The effect of coenzyme Q10 prepared as an oil solution and a water-soluble suspension (the Kudesan preparation) on the resistance of myocardium of Wistar rats to ischemic and reperfusional injuries and the redox state of the components of the cardiac mitochondrial respiratory chain during postischemic reperfusion was studied. Animals received the oil solution of Q10 with food and the Kudesan preparation, with water. It was shown that the drugs, which produce a substantial protective action on the working heart muscle during ischemia and reperfusion, cause a shift of the redox equilibrium between the semireduced forms of ubiquinone and flavine coenzymes to a higher output of ubisemiquinone. With equal doses of the drugs, Kudesan produced a more pronounced effect.

Relevance of intraocular involvement in the management of primary central nervous system lymphomas.

BACKGROUND: Reported data regarding intraocular lymphoma (IOL) management are anecdotal. Cases of IOL included in an international multicentre series of 378 immunocompetent patients with primary central nervous system lymphomas (PCNSLs) were reviewed. PATIENTS AND METHODS: Staging included slit-lamp examination in 170 patients: IOL was diagnosed in 22 cases (13%). A concomitant brain lesion was detected in 21 cases. Planned treatment was chemotherapy followed by radiotherapy in 13 cases, chemotherapy alone in three and radiotherapy, followed by or not by chemotherapy in five; one patient was not treated. Chemotherapy included high-dose methotrexate in 12 cases. Ten patients received intrathecal chemotherapy. Radiotherapy consisted of whole brain irradiation, followed by or not by a tumour bed boost; ocular irradiation was planned in 15 cases. Irradiation in one patient without brain lesions was limited to the orbits only (50 Gy). RESULTS: IOL was positively correlated to systemic symptoms and meningeal disease. Fifteen patients (71%) achieved an objective response; 16 patients experienced a failure (2-year failure-free survival 34+/-10%). Failures involved the eyes in eight cases, with a 2-year time to ocular relapse of 59+/-11%. Ocular failure was less common in patients treated with chemotherapy plus ocular irradiation and was associated with a significantly shorter survival. Seven patients are alive [median follow-up 53 months, 2-year overall survival (OS): 39+/-11%] , five of whom were treated with ocular irradiation. The patient with isolated IOL is alive and disease-free at 14 months. OS of the entire series was similar to that of PCNSL patients with negative slit-lamp examination. CONCLUSIONS: IOL is usually associated with concomitant brain disease and shows a survival similar to that of the rest of PCNSLs. Chemotherapy combined with ocular irradiation resulted in better control of ocular disease, which seems to be associated with survival. In view of the potential role of ocular irradiation, the use of chemotherapy alone in phase II trials should be critically reconsidered in PCNSL patients with ocular disease.