Enhanced sensitivity in THz plasmonic sensors with silver nanowires.

We developed hybrid slot antenna structures for microbial sensing in the THz frequency range, where silver nanowires (AgNWs) were employed to increase the sensitivity. In order to fabricate the hybrid devices, we partially etched the AgNW in the slot antenna region, where we can expect the field enhancement effect at the AgNW tip. We measured the resonant-frequency shift observed upon the deposition of a polymer layer, and observed that the sensitivity increased upon the introduction of AgNWs, with an enhancement factor of more than four times (approximately six times in terms of figure-of-merit). The sensitivity increased with the AgNW density until saturation. In addition, we tested devices with PRD1 viruses, and obtained an enhancement factor of 3.4 for a slot antenna width of 3 µm. Furthermore, we performed finite-difference time-domain simulations, which confirmed the experimental results. The sensitivity enhancement factor decreased with the decrease of the slot width, consistent with the experimental findings. Two-dimensional mapping of the electric field confirmed the strong field localization and enhancement at the AgNW tips.

Sensing viruses using terahertz nano-gap metamaterials.

We demonstrate highly sensitive detection of viruses using terahertz split-ring resonators with various capacitive gap widths. Two types of viruses, with sizes ranging from 60 nm (PRD1) to 30 nm (MS2), were detected at low densities on the metamaterial surface. The dielectric constants of the virus layers in the THz frequency range were first measured using thick films, and the large values found identified them as efficient target substances for dielectric sensing. We observed the resonance-frequency shift of the THz metamaterial following deposition of the viruses on the surface at low-density. The resonance shift was higher for the MS2 virus, which has a relatively large dielectric constant. The frequency shift increases with surface density until saturation and the sensitivity is then obtained from the initial slope. Significantly, the sensitivity increases by about 13 times as the gap width in the metamaterials is decreased from 3 µm to 200 nm. This results from a combination of size-related factors, leading to field enhancement accompanying strong field localization.

[Adenocystic carcinoma of the trachea]. / Adenokistoznyi rak trakhei.

It is presented 40-years experience of tracheal adenocystic carcinoma diagnosis and management in 144 patients. Peculiarities of clinical course and choice of diagnostic and therapeutic measures are discussed in relation to stenosis and hypoxia degree and severity of accompanying inflammatory complications of trachea, bronchi and lungs. Technical tools and original methods of resection and reconstruction of trachea and it's bifurcation after extended lung resection are described. Surgical management is carried out in 96 patients: all patients underwent circular resection of trachea (77) or it's bifurcation (19). Morbidity rate was 22.9% and mortality - 3.1%. Additional radiotherapy was carried out in 50 patients. 41 patients underwent radiotherapy alone. Radiotherapy improves remote results of management. 5-and 10-year survival rate was 78.3±6.1 and 45.9±7.9% after surgery alone, 92.0±3.9 and 77.1±6.5% after combined treatment and 76.4±6.5 and 55.0±10.7% after radiotherapy alone respectively.

[Current problems of postoperative radiotherapy for non-small cell lung cancer].

The review considers the history of evolution and the present state of the problem of postoperative radiotherapy for non-small cell lung cancer. The randomized trials and meta-analyses given in recent publications provide evidence that it should be used in radically operated patients with morphologically verified regional metastases. The paper also shows promises of hypofractionation and a postoperative radiation/chemotherapy ratio for non-small cell lung cancer.

Removal of Mycobacterium avium subspecies hominissuis (MAH) from drinking water by coagulation, flocculation and sedimentation processes.

UNLABELLED: There has been a growing concern over human exposure to Mycobacterium avium subspecies hominissuis (MAH) through drinking water due to its ubiquitous presence in natural waters and remarkable resistance to both chemical and physical disinfectants in drinking water treatment processes. However, little is known about the effectiveness of physico-chemical water treatment processes to remove MAH. Therefore, we determined the removal of MAH by alum coagulation, flocculation and sedimentation processes in optimized drinking water treatment conditions using standard jar test equipment. Contrary to the prevailing hypothesis, the results of this study show that removal of MAH by coagulation, flocculation and sedimentation processes was only moderate (approx. 0.65 log10) under low turbidity treatment conditions and the removal of MAH was actually lower than that of Escherichia coli (reference bacterium) in all the waters tested. Overall, the results of this study suggested that coagulation, flocculation and sedimentation processes may not be a reliable treatment option for removing MAH, and more efforts to find an effective control measures against MAH should be made to reduce the risk of MAH infection from drinking water. SIGNIFICANCE AND IMPACT OF THE STUDY: Despite a growing concern over human exposure to Mycobacterium avium subspecies hominissuis (MAH) through drinking water and its remarkable resistance to water disinfectants, little is known about the effectiveness of physico-chemical water treatment processes to remove MAH. Contrary to the prevailing hypothesis, the results of this study suggest that coagulation, flocculation and sedimentation processes may not be a reliable treatment option for MAH removal. As these processes have been the last remaining conventional drinking water treatment processes that might be effective against MAH, more efforts should be urgently made to find an effective control measures against this important waterborne pathogen.

[Economic and logistical problems of radiation oncology].

An analysis of economic and logistical problems of radiation oncology is presented based on domestic and foreign literature. Despite the high efficacy of radiotherapy this branch of oncology is not financed enough in most countries. As a consequence, it is ubiquitously marked radiotherapy capacity deficit that does not allow to fully realize its therapeutic potential. Medical electron accelerators and related equipment have become increasingly complex and expensive and radiotherapy techniques more consuming. Even in developed countries growing waiting times for radiotherapy, not using the most modern and efficient radiotherapy technologies (image guiding, etc.) has become a daily reality. Based on these data, we assessed the prospects and possibilities of upgrading the technical base of radiation oncology in Russia including the development of hadron therapy.

[Evaluation the effectiveness of radiation therapy high-grade gliomas based on the model of TDF (time-dose fractionation)].

There were showed the possibility of using the model of TDF, through which it was possible to take into account the selection of fractionation of radiation for high-grade gliomas and to judge the effectiveness of treatment. Currently, the basis of adjuvant radiation therapy in patients with primary high-grade gliomas is the use of the traditional mode of fractionation dose of radiation from a single focal dose of 2 Gy up to a total focal dose of 60 Gy to the tumor (bed of the removed residual tumor) in Grade 4 and Grade 3 - 54 Gy. In patients who underwent radiotherapy using a single focal dose of 3 Gy, overall survival rate was higher as compared to the group of patients, which was carried out using radiotherapy small dose fractionation.

[The role of functional status and recursive partition analysis (RPA) classes for the choice of fractionation regimen in patients with high-grade gliomas].

The treatment results of 396 patients with morphologically verified grade 3-4 malignant brain tumors receiving conventional irradiation regimen and irradiation by medium-sized fractions were analyzed to form institutional guidelines.The standard mode of fractionation with a single dose of 2 Gy and total focal dose (TFD) of 60 Gy is appropriate for patients with initial Karnofsky status of 60-100% and Recursive Partition Analysis (RPA) class I-III. TFD increase to 60-62 Gy in grade 4 gliomas and 54-56 Gy in grade 3 gliomas grants a significant improve in overall survival. An increase of a single irradiation fraction to 3 Gy may be used for patients with initially low functional status (Karnofsky 30-50%) and RPA classes IV-VI. In these cases it is advisable to use the TFD of 45 Gy or more (TFD of equivalent regimen with a dose greater than 54 Gy). The mentioned fractionation regimens could be recommended for the use in clinical practice to improve the results of high-grade gliomas treatment.

[The role of age and tumor grade in the choice of fractionation regimen in patients with high-grade gliomas].

There are currently no conventional guidelines for radiotherapy in gliomas. The treatment program is mainly formed in accordance with tumor morphology and the "golden standard" of irradiation is still the traditional mode of fractionation with a single focal dose of 2 Gy and total focal dose (TFD) of 60 Gy. In this report the treatment results of 396 patients with morphologically verified grade 3-4 malignant brain tumors receiving conventional irradiation regimen and irradiation by medium-sized fractions were analyzed to form institutional guidelines. The standard fractionation mode with a single focal dose of 2 Gy is preferable in patients with grade 3 glioma or elderly patients (over 60 years). TFD increase to 60-62 Gy in grade 4 gliomas and 54-56 Gy in grade 3 gliomas grants a significant improve in overall survival. An increase of a single irradiation fraction to 3 Gy may be used for patients younger than 60 years. In these cases it is advisable to use the TFD of 45 Gy or more (TFD of equivalent regimen with a dose greater than 54 Gy). The mentioned fractionation regimens could be recommended for the use in clinical practice to improve the results of high-grade gliomas treatment.

[Optimal doses and timing for tele-irradiation of bone metastases in patients with life expectancy more than 3 months].

The aim of the current study was to improve the bone metastases irradiation parameters in patients with life expectancy more than 3 months. The current randomized study included a total of 333 patients with bone metastases (breast cancer metastases in 71% of cases) receiving 488 courses of photon irradiation. Irradiation effect was observed in 95.8-100% of cases regardless of fraction number and irradiation regimen. The rate of complete effect was the same for all irradiation regimens, but raised gradually from 33.3% to 50.4% and 65.9% respectively when irradiation was given by 2, 3 and 4 fractions, 6,5 Gy each (p < 0.03); 78.4% (p < 0.01) cases of complete effect were observed in patients receiving irradiation by multiple small fraction compared to the groups receiving irradiation by 2 or 3 fractions of 6.5 Gy. The complete effect was more often observed in breast cancer (67%) and prostate cancer (63%) patients in comparison to lung cancer (47%) and renal cancer (30%) patients (p < 0,05) independent of metastases localization. The mean frequency of pain recurrence in irradiated area was 8.2% in all primary tumor and metastases localizations, irrespective of irradiation dose and regimen. Based on above results we recommend for breast cancer and prostate cancer patients with bone metastases and life expectancy more than 3 months the irradiation with 19.5 Gy given by 3 fractions. The patients with metastasizing lung and renal cancer should receive 26 Gy irradiation by 4 fractions 6.5 Gy each given once every 5.

[The optimal radiation volume after first-line chemotherapy in Hodgkin lymphoma].

Radiation therapy has evolved from extended-field radiation therapy (EFRT) to involved-field radiation therapy (IFRT), reducing toxicity while maintaining high cure rates. Recent publications recommend a further reduction to involved-nodal radiation therapy (INRT); however, this has not been clinically validated. The need for irradiation or optimal radiation volume after chemotherapy are not defined. The treatment results of 296 Hodgkin's disease patients receiving ABVD or BEACOPP-21 chemotherapy with consequent EFRT demonstrate CR/PR > or = 80% and 99% local disease control rate. Beam therapy with EFRT is possible to use if dose levels don't exceed 30 Gy. Higher doses demands reduction of volume of radiating target. In our opinion the optimum program of beam therapy involves 2 stages with maximal possible dose level EFRT followed by additional INRT. Those approaches offer perspectives for Hodgkin's disease treatment.

[Role of response to first-line chemotherapy and of the primary lesion in Hodgkin lymphoma].

Based on the results of combined treatment with inclusion of ABVD and BEACOPP-21 chemotherapy regimens the basic principles of therapy depending on the nodal relaps criterium were developed. The most rational approach to treatment results evaluation concerns the lesions with the least response to chemotherapy. The groups of "adequate" and "inadequate" response to chemotherapy should be formed. The initial lesion localisation doesn't play an important part in the modern chemotherapy settings and should not be concerned while choosing tactics of radiation therapy. The method described should interest oncologists and radiologists involved in the treatment of Hodgkin lymphoma.

[Options of hypofractionation of proton boost in locally advanced prostate cancer].

The aim was to evaluate the effectiveness of various fractionation proton boost in the proton-photon radiation therapy of locally advanced prostate cancer. The study included 272 patients with prostate cancer and intermediate-to-high risk of progression. 114 patients received 3-D conformal local irradiation of the prostate by proton beam 220Mev. The focal dose of 28-28,8 SoGy-eq was fed to the prostate for 8, 5 or 3 fractions for 3, 4 or 5.5 Gy-eq, respectively. Given the photon component (44 Gy in 22 fractions to the whole volume of the pelvis), the dose to the prostate was 72.8., 72 and 72SoGr-eq, respectively. In 158 patients in the control group the similar doses to the pelvis were supplemented by local 4-dipole photon irradiation of the prostate to 68-72 Gy in 12-14 fractions of 2 Gy. Acute gastro-intestinal (GI) toxicity maximum, 2 St expression, were found significantly less frequently after the proton-photon therapy: in 54.4% of cases, versus 69.2% in the controls (p <0,01). Differences between acute genito-urinary (GU) toxicity were not observed. The frequency of late GI damage of 2 St. was 3 times less frequently observed in the study group: 10.2% versus 34,8 +/-% in controls. Damages of 3-4 St. were found in 1 patient of the main group and in 2 patients in the control group. GU damages of 2 St. were equally common after the proton-photon or just photon irradiation in 8.3% and 9.1% of patients respectively. Damages of 3-4 St. were diagnosed in 2.8% and 3.8%, respectively (p> 0.05). A 5-year survival without biochemical recurrence was in the study and control groups 60,0 +/- 5,4% and 61,9 +/- 4,4%, and a 9-year survival--45,5 +/- 8,5% and 42,8 +/- 7 1%, respectively (p > 0.05). Thus, precise local irradiation by a proton beam with ROD 3-5.5 Gy-eq. and SOD 28-28,8 Gy-eq supplementing photon irradiation of total small pelvis significantly reduces the severity of early and late post-radiation proctitis but does not reduce the risk of damage to the lower urinary tract and does not influence the anti-tumor treatment effectiveness compared to conventional conformal photon radiotherapy. In this case, the proton boost modes: 8 fractions for 3 Gy, 5 fractions for 4 Gy and 3 fractions for 5.5 Gy does not significantly differ in the level of toxicity.

[The role of RPA classification in the treatment of high-grade gliomas].

One of the main gliomas treatment programs development criteria is still the morphology, the RPA classification with risk factors developed for high-grade tumors is rarely taken into consideration. In our study shows a high value on the criterion of overall survival identified in the classification of the six RPA classes. The most important factors in the RPA classification are patient's age and the Karnofsky performance scale value. RPA classification can be useful for new treatment strategies development.

[The optimal total focal radiotherapy dosage after first-line chemotherapy in patients with Hodgkin lymphoma].

Based on the treatment results of 300 Hodgkin lymphoma patients the authors formulated the basic approaches for radiation treatment in ABVD and BEACOPP-21 chemotherapy regimens recipients. In patients with complete response to chemotherapy any dose regimen (26 to 44 Gr) leads to 100% local disease control. In patients with major response to chemotherapy (PR> or =80%) the 36 Gr total focal dose allows an adequate local control, more intensive local control doesn't yield better results. In patients with PR 0-79% the implication of total focal doses less than 40 Gr leads to statistically significant increase of nodal relapse rate. These treatment approaches may be implied by specialists conducting chemotherapy and radiation therapy in Hodgkin lymphoma patients.

[Surgical and combined treatment for primary carcinoma of the trachea].

Our study was conducted in patients with primary squamous cell carcinoma of the trachea and adenoid cystic carcinoma (191) (radical surgery--90; combined treatment--101). The former pathology was relatively more aggressive. Combined treatment proved more effective as compared with surgery alone (5- and 10-year survival after surgery was 79 and 64%; combined treatment--92 and 79%, respectively).

[Radical radiotherapy of primary cancer of the trachea].

The paper deals with the importance of treatment of primary cancer of the trachea and, in particular, the experience of the Center in using radical therapy for inoperable squamous cell tumors and adenoid cystic carcinoma. An original system of tumor staging developed at the Center draws on international classifications (TNIVI) and methods of radiotherapy depending on tumor localization. It is shown that tracheal malignancies, especially adenoid cystic carcinomas, are characterized by relatively high radiosensitivity.

[Risk factors and long-term results of radiotherapy in grade-3 and -4 brain neoplasms].

Data on the treatment of 278 patients with brain tumors grade III-IV were evaluated, end-results compared and relevant prognostic factors identified. In our view, average fractionated radiotherapy is not inferior to standard fractionation modalities. It offers an advantage of using different single target doses. In primary patients with high-grade malignancies, an index (Karnofsky) of less than 60% appeared to be the most significant practical factor of prognosis. Both age and tumor size proved significant.

[Risk factors for hematologic toxicity and multifaceted analysis of blood in Hodgkin's disease: a model for hematologic toxicity].

Basic hematological features of CEA/ABVD medication for Hodgkin's disease were studied. An effective model was worked out on the principle of data discrimination for predicting different leukocytic toxicities induced by cytostatics-1 administration, once in two weeks. It might predict individual limits (dosage and intervals) of a chemotherapy course unless a colony-stimulation technique is used.