Anisotropy of radiation-induced defects in Yb-implanted ß-Ga2O3.

RE-doped ß-Ga2O3 seems attractive for future high-power LEDs operating in high irradiation environments. In this work, we pay special attention to the issue of radiation-induced defect anisotropy in ß-Ga2O3, which is crucial for device manufacturing. Using the RBS/c technique, we have carefully studied the structural changes caused by implantation and post-implantation annealing in two of the most commonly used crystallographic orientations of ß-Ga2O3, namely the (-201) and (010). The analysis was supported by advanced computer simulations using the McChasy code. Our studies reveal a strong dependence of the structural damage induced by Yb-ion implantation on the crystal orientation, with a significantly higher level of extended defects observed in the (-201) direction than for the (010). In contrast, the concentration and behavior of simple defects seem similar for both oriented crystals, although their evolution suggests the co-existence of two different types of defects in the implanted zone with their different sensitivity to both, radiation and annealing. It has also been found that Yb ions mostly occupy the interstitial positions in ß-Ga2O3 crystals that remain unchanged after annealing. The location is independent of the crystal orientations. We believe that these studies noticeably extend the knowledge of the radiation-induced defect structure, because they dispel doubts about the differences in the damage level depending on crystal orientation, and are important for further practical applications.

Crystal Lattice Recovery and Optical Activation of Yb Implanted into ß-Ga2O3.

ß-Ga2O3 is an ultra-wide bandgap semiconductor (Eg~4.8 eV) of interest for many applications, including optoelectronics. Undoped Ga2O3 emits light in the UV range that can be tuned to the visible region of the spectrum by rare earth dopants. In this work, we investigate the crystal lattice recovery of (2¯01)-oriented ß-Ga2O3 crystals implanted with Yb ions to the fluence of 1 ×1014 at/cm2. Post-implantation annealing at a range of temperature and different atmospheres was used to investigate the ß-Ga2O3 crystal structure recovery and optical activation of Yb ions. Ion implantation is a renowned technique used for material doping, but in spite of its many advantages such as the controlled introduction of dopants in concentrations exceeding the solubility limits, it also causes damage to the crystal lattice, which strongly influences the optical response from the material. In this work, post-implantation defects in ß-Ga2O3:Yb crystals, their transformation, and the recovery of the crystal lattice after thermal treatment have been investigated by channeling Rutherford backscattering spectrometry (RBS/c) supported by McChasy simulations, and the optical response was tested. It has been shown that post-implantation annealing at temperatures of 700-900 °C results in partial crystal lattice recovery, but it is accompanied by the out-diffusion of Yb ions toward the surface if the annealing temperature and time exceed 800 °C and 10 min, respectively. High-temperature implantation at 500-900 °C strongly limits post-implantation damage to the crystal lattice, but it does not cause the intense luminescence of Yb ions. This suggests that the recovery of the crystal lattice is not a sufficient condition for strong rare-earth photoluminescence at room temperature and that oxygen annealing is beneficial for intense infrared luminescence compared to other tested environments.

Enhanced Luminescence of Yb3+ Ions Implanted to ZnO through the Selection of Optimal Implantation and Annealing Conditions.

Rare earth-doped zinc oxide (ZnO:RE) systems are attractive for future optoelectronic devices such as phosphors, displays, and LEDs with emission in the visible spectral range, working even in a radiation-intense environment. The technology of these systems is currently under development, opening up new fields of application due to the low-cost production. Ion implantation is a very promising technique to incorporate rare-earth dopants into ZnO. However, the ballistic nature of this process makes the use of annealing essential. The selection of implantation parameters, as well as post-implantation annealing, turns out to be non-trivial because they determine the luminous efficiency of the ZnO:RE system. This paper presents a comprehensive study of the optimal implantation and annealing conditions, ensuring the most efficient luminescence of RE3+ ions in the ZnO matrix. Deep and shallow implantations, implantations performed at high and room temperature with various fluencies, as well as a range of post-RT implantation annealing processes are tested: rapid thermal annealing (minute duration) under different temperatures, times, and atmospheres (O2, N2, and Ar), flash lamp annealing (millisecond duration) and pulse plasma annealing (microsecond duration). It is shown that the highest luminescence efficiency of RE3+ is obtained for the shallow implantation at RT with the optimal fluence of 1.0 × 1015 RE ions/cm2 followed by a 10 min annealing in oxygen at 800 °C, and the light emission from such a ZnO:RE system is so bright that can be observed with the naked eye.

Charge Storage and Reliability Characteristics of Nonvolatile Memory Capacitors with HfO2/Al2O3-Based Charge Trapping Layers.

Flash memories are the preferred choice for data storage in portable gadgets. The charge trapping nonvolatile flash memories are the main contender to replace standard floating gate technology. In this work, we investigate metal/blocking oxide/high-k charge trapping layer/tunnel oxide/Si (MOHOS) structures from the viewpoint of their application as memory cells in charge trapping flash memories. Two different stacks, HfO2/Al2O3 nanolaminates and Al-doped HfO2, are used as the charge trapping layer, and SiO2 (of different thickness) or Al2O3 is used as the tunneling oxide. The charge trapping and memory windows, and retention and endurance characteristics are studied to assess the charge storage ability of memory cells. The influence of post-deposition oxygen annealing on the memory characteristics is also studied. The results reveal that these characteristics are most strongly affected by post-deposition oxygen annealing and the type and thickness of tunneling oxide. The stacks before annealing and the 3.5 nm SiO2 tunneling oxide have favorable charge trapping and retention properties, but their endurance is compromised because of the high electric field vulnerability. Rapid thermal annealing (RTA) in O2 significantly increases the electron trapping (hence, the memory window) in the stacks; however, it deteriorates their retention properties, most likely due to the interfacial reaction between the tunneling oxide and the charge trapping layer. The O2 annealing also enhances the high electric field susceptibility of the stacks, which results in better endurance. The results strongly imply that the origin of electron and hole traps is different-the hole traps are most likely related to HfO2, while electron traps are related to Al2O3. These findings could serve as a useful guide for further optimization of MOHOS structures as memory cells in NVM.

Structural Properties of Thin ZnO Films Deposited by ALD under O-Rich and Zn-Rich Growth Conditions and Their Relationship with Electrical Parameters.

The structural, optical, and electrical properties of ZnO are intimately intertwined. In the present work, the structural and transport properties of 100 nm thick polycrystalline ZnO films obtained by atomic layer deposition (ALD) at a growth temperature (Tg) of 100-300 °C were investigated. The electrical properties of the films showed a dependence on the substrate (a-Al2O3 or Si (100)) and a high sensitivity to Tg, related to the deviation of the film stoichiometry as demonstrated by the RT-Hall effect. The average crystallite size increased from 20-30 nm for as grown samples to 80-100 nm after rapid thermal annealing, which affects carrier scattering. The ZnO layers deposited on silicon showed lower strain and dislocation density than on sapphire at the same Tg. The calculated half crystallite size (D/2) was higher than the Debye length (LD) for all as grown and annealed ZnO films, except for annealed ZnO/Si films grown within the ALD window (100-200 °C), indicating different homogeneity of charge carrier distribution for annealed ZnO/Si and ZnO/a-Al2O3 layers. For as grown films the hydrogen impurity concentration detected via secondary ion mass spectrometry (SIMS) was 1021 cm-3 and was decreased by two orders of magnitude after annealing, accompanied by a decrease in Urbach energy in the ZnO/a-Al2O3 layers.

Management and follow-up of Ewing sarcoma patients with isolated lung metastases.

BACKGROUND: Ewing sarcoma (ES) is the second most common pediatric malignant bone tumor with a wide spectrum of clinical presentations. Although metastatic disease to the lungs is often the cause of death, isolated lung metastases at diagnosis are not frequent. The specific role of chemotherapy, surgery, and lung radiation has not been clearly defined. We investigated prognostic factors and the impact of the different treatment modalities in a cohort of patients with ES with isolated lung metastases. MATERIALS AND METHODS: Thirty-eight patients with ES and isolated lung metastases were treated using modern multimodal therapy during the period 2000-2014. According to the imaging characteristics of lung nodules patients were allocated into one of four treatment groups: "0" without nodules, "1" one solitary nodule of <0.5cm or several nodules of <0.3cm, "2" solitary nodule of 0.5-1cm or multiple nodules of 0.3-0.5cm, "3" one pulmonary/pleural nodule of >1cm, or more than one nodule of >0.5cm. Factors predictive of outcome were analyzed. Overall survival was estimated by Kaplan-Meier methods and compared using long-rank test and Cox models. RESULTS: Treatment of the lung metastases was performed in 23 cases (60.5%): twenty patients underwent lung surgery, 6 of them received additional postoperative whole lung radiation; three patients received lung radiation only. Malignant cells were found in all lung nodules of patients from group "3", in 5 (62.5%) patients from group "2", and none of the group "1". There was a correlation between histological response of the primary tumor and outcome. Three-year estimates of EFS and OS were 45.19% and 60.7%, respectively. Patients with good response measured by chest CT had significantly better EFS than patients with poor response (81% vs. 27.66%, respectively, p=0.006). CONCLUSIONS: Metastatectomy may have a role in the treatment of highly selected patients with ES and isolated lung metastases depending on the histologic response to therapy. Further studies are needed to better define the use of surgery and the response-adapted criteria in the upfront management of this population.

Internal hemipelvectomy in the management of pelvic Ewing sarcoma - are outcomes better than with radiation therapy?

BACKGROUND: Pelvic Ewing sarcoma (ES) is commonly associated with a worse prognosis. Large size and location limit local control options to radiation therapy, and local recurrences are common. We evaluated the impact of hemipelvectomy and radiation on outcomes, including function. MATERIALS AND METHODS: Thirty-nine patients (median age 13.5years) with ES of the pelvis and sacral bones were treated during the period 2000-2012. Fifteen were treated with definitive radiotherapy (RT), 9 patients underwent hemipelvectomy alone, and 15 were treated with combined hemipelvectomy and RT. RESULTS: Twenty patients (51.2%) are alive with a median follow-up 3.2years from diagnosis. Median time from diagnosis to relapse was 1.3years. Three-year estimates of EFS and OS were 47% and 61%, respectively. Patients treated with surgery or surgery with RT had better outcome than patients treated with RT only (3-year OS 78% or 81% vs. 36%, respectively, p=0.00083). The outcome of patients with pelvic ES treated with hemipelvectomy was not significantly different from the outcome of all patients with Ewing sarcoma treated on the national Polish protocol. CONCLUSIONS: Internal hemipelvectomy offers good chances of cure for patients with pelvic ES, with a reasonable rate of complications and good function.

[Evaluation of selected parameters of specific immunity in children with osteosarcoma at various stages of antitumour treatment].

UNLABELLED: Typical cells of specific immunity are lymphocytes. T cells may specifically recognize antigens using T Cell Receptors (TCRs). Antigen presentation by specialized cells is a necessary element of specific immunity. It leads to initiating an immune response. After antigen dependent activation T cells transform to memory and effector lymphocytes. Cells engaged directly in destruction of the tumour are CD8+cytotoxic T lymphocytes, CD4+ lymphocytes, Tγδ lymphocytes, NK, NKT cells and indirectly B lymphocytes. One of the main methods of osteosarcoma treatment in children is chemotherapy. The goal is to destroy the cancer cells by putting them in a state of apoptosis. All of the medications used as chemotherapy carry the risk of short-term and long-term problems including leukopenia, immune disorders such as immunodeficiency. THE AIM OF STUDY: was evaluation by flow cytometry selected elements of specific cellular immunity in children with osteosarcoma at various stages of antitumour treatment. MATERIALS AND METHODS: The study was performed on the group of 44 children with osteosarcoma, aged from 6 to 20 years (average 14.9 years; median 15.0 years). T and B lymphocytes and subpopulations: CD4+, CD8+, CD3+?HLA-DR+, CD3+γδ; NK, NKT cells were analyzed in peripheral blood with use of flow cytometry method with monoclonal antibodies. Examinations were performed before the therapy - in diagnostic period (examination I), after the neoadjuvant chemotherapy (examination II), 10-14 days after the surgery (examination III), 5 months after the surgery (after adjuvant chemotherapy, examination IV). RESULTS: The number of T and B lymphocytes was decreasing after each stage of cytostatic therapy, with the biggest differences for CD19+ cells (medians: I examination - 205.0; II exam. - 62.0; IV exam. - 24.0 cells/mL); in single cases the number of cells decreased even under 10/mL (norm 200-500 cells/mL). CONCLUSIONS: 1. In children and youth with osteosarcoma antineoplastic treatment contributes to the suppression of the immune system, decreasing definitely the number and percentage of B lymphocytes, T helper lymphocytes and NK cells. 2. Decreased number of CD3+, CD4+, CD19+ and NK lymphocytes during chemotherapy may contribute to the progression of neoplastic disease in the future, after treatment. 3. Evaluation of immunologic status in patients with osteosarcoma may be helpful in monitoring of antineoplastic therapy effectiveness, may prevent the formation of unfavourable clinical changes and may be the basis for correction of the cytostatic agents' administration.

Validation of a multi-modal treatment protocol for Ewing sarcoma--a report from the polish pediatric oncology group.

BACKGROUND: Ewing sarcoma (ES) is the second most common paediatric malignant bone tumor. Advances in multi-disciplinary care have resulted in significant improvement in cure rates over the last decades. However, the generalization of those results in countries traditionally excluded from large cooperative trials has yet to be demonstrated. We report the results of modern multi-disciplinary care for patients with ES in Poland. PROCEDURES: One hundred and thirty-two patients with ES were treated using modern multi-modal therapy during the period 2000-2009. Overall survival was estimated by Kaplan-Meier methods and compared using long-rank test and Cox models. Factors predictive of outcome in our setting were analyzed to identify distinct risk groups that could help identify areas for improvement. RESULTS: The median age at the time of diagnosis was 12.3 years. With a median follow-up of 5.0 years, the 5-year event-free survival (EFS) and OS estimates for localized disease were 54.88% and 68.29%, respectively. For patients with metastatic disease, 5-year EFS and OS estimates were 36% and 42%, respectively. There was no correlation between age and stage or site. Patients with localized, non-pelvic disease had better outcome than patients with axial tumors (71% vs. 44%, respectively, P = 0.00073). Treatment failure was associated with stage, pelvic primary, poor histological response, and type of local control. CONCLUSIONS: Successful treatment of ES requires optimal systemic and local therapy. We were able to replicate the results of modern multi-modal protocols. Validation of current treatment protocols in countries with more limited cancer treatment resources is required.

[Chemotherapy in patients with refractory Ewing sarcoma]. / Chemioterapia u dzieci i mlodziezy z opornymna leczenie miesakiem Ewinga

BACKGROUND: Patients with metastatic, progressive or recurrent Ewing sarcoma have a poor prognosis. In addition to increasing the intensity of conventional chemotherapy, the combination of irinotecan and temozolomide has been proposed as an effective salvage regimen for some pediatric malignancies. AIM: To evaluate the effect of two different salvage regimens on the final outcome of patients with refractory Ewing sarcoma. MATERIAL AND METHODS: During the period 2008-2012, twenty-two patients (age between 2.9 -19.3 years) with recurrent or refractory Ewing sarcoma were treated with the combination of vincristine, irinotecan and temozolomide (VIT regimen), and twenty patients were treated with the combination of cisplatin, doxorubicin, cyclophosphamide and teniposide (PACE regimen). All patients had standard tumour imaging and laboratory evaluation. All toxicities were documented. The WHO criteria were used to evaluate response. Statistical analysis was performed using STATA 10.0 for Windows. Results distributions were estimated using the method of Kaplan-Meier. The log-rang test was used to compare the groups. RESULTS: A total of 91 cycles of VIT and 65 cycles of PACE were administered. For VIT therapy the overall response rate was 68.1%. Median time to progression was 3.0 months. Five patients are alive with no evidence of disease with a median follow-up of 10.3 months. For PACE therapy the overall response rate was 75%. Median time to progression was 3.5 months. Four patients are alive with no symptoms of disease with a median follow-up of 17.6 months. The 2 years overall survival probability after recurrence was 29.94%; no differences were detected between therapy groups. Toxicity for PACE was significantly higher. CONCLUSIONS: The effectiveness of VIT regimen in refractory Ewing Sarcoma is comparable to conventional chemotherapy. The VIT regimen has less associated toxicities than the PACE regimen.

Vincristine, irinotecan, and temozolomide in patients with relapsed and refractory Ewing sarcoma.

BACKGROUND: Patients with metastatic, progressive or recurrent Ewing sarcoma (ES) have a dismal outcome. The combination of irinotecan and temozolomide has been proposed as an effective salvage regimen for some pediatric malignancies. Thus, we sought to evaluate this combination with vincristine for patients with relapsed and refractory ES. MATERIALS AND METHODS: Twenty-two patients with relapsed or refractory ES were treated with the combination of vincristine (1.5 mg/m(2) i.v. day 1), irinotecan (50 mg/m(2) /day i.v. days 1-5) and temozolomide (125 mg/m(2) /day p.o. days 1-5) (VIT) during the period 2008-2012. All toxicities were documented. RESULTS: A total of 91 cycles (median 4.1 cycles/patient) were administered. A complete response (CR) was achieved in five patients, partial response (PR) in seven patients, stable disease (SD) in three patients, and progression disease (PD) in seven patients, with an overall response rate of 68.1%. Median time to progression was 3.0 months (range 1.1-37.1 months). Five patients (22.7%) are alive with no evidence of disease with a median follow-up of 10.3 months (range 2.1-46.5); four of them received consolidation with high-dose chemotherapy and autologous hematopoietic stem cell transplant after responding to VIT. Outcome was better for patients with relapsed ES compared with patients who progressed to initial therapy (estimated 2 year overall survival 36.4% vs. 0%, respectively). There were no significant toxicities. CONCLUSIONS: The shorter, 5-day VIT regimen is an active and well-tolerated regimen in refractory ES. This combination deserves further investigation in the upfront management of patients with metastatic disease.

Continuous veno-venous hemodiafiltration in methotrexate intoxication.

UNLABELLED: Methotrexate is a highly nephro- and hepatotoxic drug used in osteosarcoma treatment protocols, in children and adults. High dose methotrexate therapy may lead to kidney injury and decrease of methotrexate clearance, followed by an increase of its serum concentration. As a result, systemic intoxication may develop. Prophylaxis based on intensive fluid therapy and urine alkalization may not be sufficient to prevent the formation of methotrexate crystals in kidney tubules. THE AIM of the study was to present three cases of methotrexate intoxication treated with continuous veno-venous hemodiafiltration. PATIENTS AND METHODS: Three children aged 9-16 years old with tibial or fibular osteosarcoma were admitted to the Nephrology Department due to severe methotrexate intoxication. All children presented with multiorgan injury, including liver, kidney, gastrointestinal tract and bone marrow impairment. Methotrexate concentration, 24 hours after drug administration, was 660-1238 µmol/L. Although intensive fluid therapy, urine alkalisation and administration of high doses of folinic acid (leucovorin), methotrexate serum concentration remained toxic. Effective reduction of methotrexate concentration (<1.5 µmol/L) was achieved 24-156 hours after CVVHDF initiation. Kidney and liver function recovered completely in all of the patients. CONCLUSION: Continuous veno-venous hemodiafiltration is an effective supportive method in methotrexate elimination in patients with severe intoxication.

[Evaluation of selected parameters of cellular immunity in children with osteosarcoma at diagnosis]. / Ocena stanu immunologicznego dzieci I mlodzinezy z miesakiem kosciopochodnym w momencie rozpoznania choroby.

UNLABELLED: The causes of osteosarcoma (OS) and effector mechanisms of the immune response against OS and other neoplastic diseases remain unknown. According to current knowledge, the major role is attributed to cytotoxic T lymphocytes, NK, NKT and Taä lymphocytes, which are engaged directly in the destruction of the tumour cells. Helper T lymphocytes (CD4+) and indirectly B lymphocytes are of special importance. There is sparse data on the state and efficiency of the immune system in children with neoplastic disease, with bone tumours in particular. THE AIM OF THE STUDY was the evaluation of selected elements of cellular immunity in children with osteosarcoma at the time of diagnosis. MATERIALS AND METHODS: The study was performed on a group of 44 children with osteosarcoma, aged from 6 to 20 years (median 15.0 years). The control group consisted of 22 children of the same age (median 14.5 years) without the diagnosis of neoplastic disease and active inflammatory state. T lymphocytes with their subpopulations, activated T lymphocytes (CD3+/HLA-DR+), B lymphocytes, NK and NKT cells were analyzed in peripheral blood using the flow cytometry method. Examinations were performed before the therapy - in the diagnostic period. RESULTS: A lower number of peripheral blood lymphocyte population in children with osteosarcoma at diagnosis, compared to the control group was observed. The differences concerned T lymphocytes CD3+(1609.0 vs 3038.0 kom/µl, p<0.001) CD4+(598.0 vs 1071.0 kom/l; p<0.001) and their cytotoxic subpopulation CD8+ (386.0 vs. 866.0 cells/µL; p<0.001), activated T lymphocytes CD3+/HLA-DR+(39.0 vs. 81.0 cells/µL; p<0.025), B lymphocytes CD19+(205.0 vs. 381.0 cells/µL; p<0.025) and NK cells (161.0 vs. 339.0 cells/µL; p<0.005). The number and percentage of peripheral blood lymphocytes in children and youth with osteosarcoma at diagnosis is over 50% lower compared to the patients without neoplastic disease. CONCLUSIONS: 1. The general analysis of peripheral blood without differentiating lymphocyte subpopulations is insufficient to determine disturbances which are forming in the immune system of patients developing the neoplastic disease. 2. The course of the neoplastic disease (osteosarcoma) in patients of developmental age is very diverse, and associated with individual biological variation. 3. The evaluation of the immunologic status in patients with osteosarcoma may have prognostic meaning for the further course of the disease, may prevent the formation of unfavourable clinical changes, and be the basis for correcting the administration of cytostatic agents.

Surgical treatment of patients with disseminated Ewing sarcoma in our clinical experience.

BACKGROUND: Survival in advanced Ewing's sarcoma is unsatisfactory even with combination treatment. This paper tries to evaluate the impact of surgical treatment on treatment results. MATERIAL AND METHODS: We discuss a series of 24 patients aged 6.1-18.9 years with disseminated Ewing's sarcoma treated in the years 2000-2008. The patients had metastases to the lungs (13 patients), bone (6 patients), or multiple sites (5 patients). The follow-up period ranged from 8 months to 8.5 years. The patients were treated in accordance with the EE99 protocol. 19 out of the 24 patients underwent surgery. Patients with lung metastases underwent resection of both the primary focus (12 children) as well as the lung metastases (6 children) or radiotherapy. Patients with metastases located elsewhere underwent resection of the primary focus and lung metastases, while the remaining metastatic sites were irradiated (7 children). The 6 remaining children received chemotherapy and radiotherapy. RESULTS: Ten of the 19 patients who were operated on are alive. All those patients that were not operated on have died. The length of survival in the whole group has ranged from 8 months to 8.5 years (mean 2.8 years). Mean overall survival among these patients that were operated on is 3.1 years, and among those who had lung metastases at baseline and underwent metastatectomy, the survival rate is 4.3 years. The average survival rate among the non-operated on patients is 1.6 years. CONCLUSIONS: Surgery appears to prolong survival among patients with disseminated Ewing's sarcoma.

[Characteristics of extracranial malignant germ cell tumours in two age groups of children (0-10 and 10-18 years). Multicentre experiences]. / Charakterystyka pozaczaszkowych zltosliwych guzów germinalnych u dzieci w dwóch grupach wiekowych 0-10 lat i 11-18 lat. Badania wieloosrodkowe.

UNLABELLED: In order to assess if any differences exist in children germ cell tumours depending on age, we compared some features of germ cell tumours in two age groups:younger than 10 and between 11 and 18 years. MATERIAL AND METHODS: Data of 146 patients with germ cell tumours treated in 15 Polish paediatric oncology departments between 1995 and 2005 were evaluated. They were divided into two groups: 76 children 0-10 years old (group I) and 70 patients 11-18 years old (group II). Tumour morphology, sex of patients, primary tumour and metastases localization, disease stage, biochemical markers, treatment response, disease relapse and long survival were analyzed. Every patient was treated according to the TGM 95 protocol. RESULTS: In group 1, 67 tumours were assessed histologically. 64%t tumours had homogenous structure with yolk sac tumour in predominance and 36% were mixed. Yolk sac tumour (YST) or teratoma as components of mixed tumours were the most commonly found. In older group 64 tumours were examined, 41% were homogenous, and seminoma/dysgerminoma predominated. In 59% mixed tumours the most common components were YST embryonal carcinoma and teratoma. The most common primary site in group I was the sacrococcygeal region while in group II - the gonads. Disseminated disease was recognized mostly in older children. Among two evaluated serum markers, AFP was increased mostly in younger patients (76% vs 44%), and 3HCG in older group (40% vs 9%). Treatment response was comparable in both groups. Two relapses were observed in each group. Poor outcome was noted in 17/140 analyzed patients: 9 (12%) in group I and 8 (11%) in group II. In 12 of patients with poor outcome the cause of death was progression and in 5 of them - treatment complications. CONCLUSIONS: 1. Germ cell tumours in younger and older children differ in histology, primary localization and serum level of biochemical markers. 2. In older patients germ cell tumours are recognized more frequently in advanced clinical stages. 3. Treatment response was comparable in both groups. 4. There is a need to analyze the intensity of chemotherapy to precise the adequate risk groups according to primary treatment response.

A prognostic evaluation of vascular endothelial growth factor in children and young adults with osteosarcoma.

BACKGROUND: The potential role of VEGF in osteosarcoma has been evaluated in several studies. The majority of them included heterogeneous and limited series of patients, giving conflicting results. The aim of presented study is to evaluate the prognostic role of VEGF-A in biopsy samples of clinically homogeneous group of osteosarcoma patients with at least 5 years of follow up. MATERIALS AND METHODS: VEGF-A was assessed immunohistochemically in the pre-treatment biopsy samples of 91 patients (mean age 14 years; range, 4-23 years) with primary, high-grade, non-metastatic osteosarcoma localized in extremities. The survival of each patient was assessed after at least 5-year follow-up period. RESULTS: VEGF-A over 50% of positive tumor cells was observed in 39% of cases and was linked to patients age below 14-year old (P = 0.025) and tumor size more than 8 cm (P = 0.054). VEGF-A was associated with a significantly decreased both overall survival (P = 0.006) and progression-free survival (P = 0.011). In the Cox proportional hazard model it was confirmed that VEGF-A expression in the biopsy samples was an independent prognostic factor of unfavorable survival in osteosarcoma (HR 2.51; 95% CI: 1.12-5.66). CONCLUSION: The expression of VEGF-A in the biopsy sample is the potential marker for predicting the course and outcome of osteosarcoma.

[A comparison of serum concentrations of biochemical bone turnover markers in patients with osteosarcoma with good and poor prognosis]. / Analiza stezenia biochemicznych markerów obrotu kostnego u chorych na miesaka kosciopochodnego z korzystnym i niekorzystnym rokowaniem.

UNLABELLED: Osteosarcoma is a primary malignant bone tumor, whose peak incidence occurs in the second decade of life during the adolescent growth spurt. Complex oncological treatment consisted of chemotherapy combined with surgery which substantially increased the cure rate of patients with osteosarcoma, but it is very important to identify patients with poor prognosis and to treat them with more aggressive therapy. THE AIM OF THIS STUDY: To assess serum biochemical bone turnover markers as prognostic indicators in patients with osteosarcoma. MATERIAL AND METHODS: We studied 55 patients from age 5 to 20 years with diagnosed osteosarcoma treated at the Institute of Mother and Child in Warsaw. The studied group was divided into 2 subgroups consisted of 27 patients with favorable (disease remission) and 28 patients with unfavorable (disease progression) prognosis. Venous blood was collected from patients in the morning hours at time of diagnosis, during anticancer treatment and after completion of treatment. Serum osteocalcin (OC), bone alkaline phosphatase (BALP) and C-terminal cross-linking telopeptide of type I collagen (CTX) were analyzed by immunoenzymatic methods. RESULTS: At time of diagnosis, in patients with unfavorable prognosis concentration of bone formation markers were higher (OC by 30% and BALP by 60%) than in those with good prognosis, however, CTX level was similar in both groups of patients. During chemotherapy in patients with poor prognosis we observed higher levels of bone turnover markers in comparison to subjects with favorable prognosis. After the completion of therapy, in patients with progression median values of bone formation markers were over twofold and bone resorption marker about 50% higher as compared to patients with remission of disease. These differences were statistically significant at p < 0.05 for OC, p < 0.001 for BALP and p < 0.01 for CTX. CONCLUSIONS: Our results suggest that bone turnover markers, especially bone alkaline phosphatise may be useful in the monitoring and in the assessment of the efficacy of therapy in children with osteosarcoma. Higher rates of bone formation and resorption during treatment and after its completion are associated with unfavorable prognosis and may indicate progression of disease.

Cognitive disorders in type 2 diabetic patients with recognized depression.

OBJECTIVES: The most important factors in the pathogenesis of cognitive disorders in diabetes mellitus (DM) are metabolic changes directly caused by hyperglycemia. Impairment of cognitive function is accompanied by a decrease in cerebral insulin. Insulin improves cognitive processes, including somatosensoric cognitive functions. Cognitive disorders are especially pronounced if diabetic patients suffer also from depression. MATERIAL AND METHODS: The evaluation of cognitive functions, especially sensomotoric skills were obtained from three study groups (aged 37-52 years): 30 healthy subjects, 40 diabetic patients with clinically documented depression and 30 depressive patients without DM. The sensomotoric skills were carried out using a SPS-2001E apparatus - a computer working stress simulator. The examination with Beck Depression Inventory (BDI) were also performed in all the investigated persons. RESULTS: Sensomotoric skills investigation revealed slight cognitive disorders in the early stages DM (subgroup IA) and its intensification according to increasing BDI scores and HbA1c blood concentration (from subgroup IA to IC). Intensification of sensomotoric cognitive disorders was significantly higher (p<0.001) in the depressive patients with DM (group I), than in these without DM (group III). CONCLUSIONS: The obtained results suggest that coincidence of aggravating factors, such as depression and metabolic disorders in DM, may cause mutual interactions leading to premature and more intense cognitive impairment. The method proposed by the authors may serve as a screening examination in early diagnosis of CNS disorders reflected by somatosensoric cognitive disorders. The presented work indicates importance of sensomotoric skills investigation for the early diagnosis of the nervous system damage related to DM.

[Evaluation of telemetric method in the assessment of heat stress of copper miners]. / Ocena przydatnosci systemu telemetrii bezprzewodowej do pomiaru obciazenia cieplnego górników w kopalniach miedzi.

BACKGROUND: The aim of this study was to assess the applicability of telemetric method in assessing heat stress of copper miners in a hot environment. MATERIAL AND METHODS: The studies were conducted in 15 mining machine operators (working without air condition). The evaluated parameters were skin temperature, core temperature, heart rate and respiration rate. RESULTS: In every examined miner we have obtained about 340 results (registrations of evaluated parameters during work shift) and this allowed us to evaluate physiological work cost and to determinate thermal homeostasis disturbances. CONCLUSIONS: The telemetric method (VitalSense System) proved to be very useful in monitoring physiological parameters of miners working in a hot environment.

[Analysis of the holter records in miners working at the deepest located work stations in copper mines of the Legnica-Glogow copper mining district]. / Wyniki analizy zapisów holterowskich u górników zatrudnionych na najglebiej polozonych stanowiskach pracy kopalni miedzi legnicko-glogowskiego okregu miedziowego.

BACKGROUND: Microclimate at mining stations consists of numerous parameters, such as air temperature, humidity, air flow velocity and rock temperature. These parameters have an impact on thermal work conditions. MATERIALS AND METHODS: The investigation was performed on 71 operators of mining machines from sections G-6 (group I) and G-11 (group II), aged 23-50 years, with mining experience of 7-25 years. One part of operators worked in air-conditioned chambers (subgroups A) and the other in chambers without air-conditioning (subgroups B). The continuous heart rate (HR) recording was taken during the whole shift. RESULTS: Average values of HR in subgroup B were significantly higher than in subgroup A, especially between 8:00 and 9:00, but the increased HR did not exceed the border line of 140 bpm. CONCLUSIONS: The results did not show significant deviation in the range of HR in operators working in unfavorable climatic conditions. They demonstrated benefits from using air-conditioned chambers to reduce effects of hot microclimate.