17 research outputs found

    Gas-loading apparatus for large-volume high-pressure cell

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    The Paris-Edinburgh cell (PEC) is a widely used opposed-anvil device for neutron scattering. Since its development, it has been used to study a number of samples loaded as solids or liquids. However, studying gases at room temperature has not yet been possible. Up until now only a few gases could be loaded as liquids, in cryogenic conditions. Thus, it was impossible to study many gases and gas mixtures and also it was difficult to use gases as pressure-transmitting media (PTM). In order to overcome these limitations, a technique that would enable loading of gases into the PEC was required. The work described in this thesis was focused on the design and use of a gas-loading system for the PEC. The challenge of designing such a system comes from the fact that the gases need to be loaded into the gasket at sufficient density in order to achieve any significant pressure during further compression in the cell. This can be achieved by using a separate pressure vessel. Because the whole PEC is too large to be placed inside the vessel, a technique of loading gas into the anvils separated from the rest of the cell had to be devised. Designing the holder for the anvils, which would make this possible, presented a major challenge as it should allow the anvils to be transferred between the vessel and the PEC, with the gasket filled with high-pressure gas. Then it needs to allow further compression of the gasket inside the PEC. The developed system consists of a pressure vessel and a locking clamp for the anvils. The pressure vessel is a closed-end thick-walled cylinder with a top cover which has an opening for a piston. The vessel is placed on the table of a hydraulic press and the piston, sealed by a high-pressure reciprocating seal, is used to transmit the force from hydraulic ram onto the anvils which are held by the clamp and placed inside the vessel. One of the anvils is fixed to the clamp and the other one is supported by spring-loaded latches - the latches engage when the anvils are pushed towards each other. Thus, when the force is applied onto the anvils to compress the gasket, latches lock the anvils in their positions stopping them from retracting and maintaining the gasket compressed after the force is released. The clamp allows the gasket to be filled with the gas and then deformed to seal the compressed gas. The locking mechanism keeps the gasket compressed, which enables the clamp to be transferred from the vessel to the PEC. After the system was built and tested, it was installed at ISIS neutron source (Oxfordshire, UK), where it has been used in several experiments. The first experiment prepared with the gas-loading system was a neutron diffraction study of nitrogen at high pressure. Nitrogen was chosen as a sample material because its high-pressure structural phase diagram is well established. Nitrogen was loaded into the gasket using the gas loader and then it was compressed in increments to 6 GPa in the PEC. β and δ phases of solid nitrogen were clearly seen in the collected neutron diffraction data. The experiment proved the usability of the gas-loading system and verified its expected performance. The second experiment utilizing the gas-loading system was to study singlecrystal and powder samples of sodium chloride (NaCl) and squaric acid (H2C4O4). For these studies argon was used as a PTM, replacing the conventionally used methanol-ethanol mixture (ME). Up until this experiment the highest pressure reported in single-crystal neutron-scattering experiments was 12 GPa. This limit was set by the solidi cation pressure of ME. With argon as the PTM, the samples were compressed to 15 GPa without any damage to the crystals. Another advantage of replacing ME with argon is improved hydrostaticity. The highest pressure that ME remain hydrostatic to is 11 GPa. Compressing beyond this point causes sheer stress acting on the sample which affects the quality of the neutron scattering data manifested in the appearance of peak-broadening in the diffraction patterns. With use of argon, the powder samples have been compressed to 18 GPa while maintaining quasi-hydrostatic pressure conditions, resulting in clean and sharp diffraction patterns without any noticeable peak-broadening

    Skin-sparing and nipple-sparing mastectomy with a positive sentinel node in patients with breast cancer

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    Introduction. A skin-sparing or nipple-sparing mastectomy is a surgical treatment that is increasingly used in the treatment of patients with breast cancer. More often women themselves decide or even ask to undergo this type of surgery. In our paper, we present the issue of combined treatment of 62 patients after nipple-sparing or skin-sparing mastectomy with a positive sentinel lymph node. Realisation of this type of surgery has further consequences in adjuvant treatment policies. Material and methods. The group of 62 previously untreated women with positive sentinel lymph nodes took part in this analysis. The individual plan of treatment was established for every patient by the multidisciplinary team according to the rules of the breast cancer unit. All patients were treated in the Holycross Cancer Centre in Kielce (in 2015–2018). Results. The early results show that proper qualification and realisation of oncological treatment is safe and effective. Severe complications appeared rarely. Conclusions. Skin-sparing or nipple-sparing mastectomy is a method of surgical treatment that is increasingly used in the treatment of patients with breast cancer. It should be remembered that the qualification for this type of procedure should be careful, and adjuvant treatment should be rationally planned. Our experience shows that it is an effective and safe method

    The prognostic value of DNA microsatellite instability analysis in breast cancer

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    Wstęp. Rak piersi jest jednym z najczęstszych nowotworów złośliwych u kobiet, a jego karcynogeneza nadal pozostajenieznana. Utrata funkcji sytemu MMR naprawiającego błędy powstałe podczas procesu replikacji DNA prowadzi doniestabilności genomu, która może być wykryta poprzez obecność polimorfizmu w mikrosatelitach (powtórzeń określonych1–6 par zasad). Jest to nazwane niestabilnością mikrosatelitarną (MSI) i jest charakterystycznym znacznikiemdysfunkcji systemu MMR w rakach jelita grubego i innych nowotworach złośliwych.Materiał i metody. W przeprowadzonej analizie badaliśmy występowanie MSI w 81 inwazyjnych rakach piersi i ocenialiśmyjej związek z cechami klinicznymi takimi jak: wiek pacjentek, wielkość guza, typ nowotworu, przerzuty do węzłówchłonnych, przerzuty do wątroby, przerzuty do mózgu, występowanie wznowy miejscowej i inne. Analizę mikrosatelitarnąprzeprowadzono za pomocą 10 markerów służących do wykrywania niestabilności mikrosatelitarnej w raku piersi.Wyniki. MSI wykryto w 40 z 81 przypadków (49,4%), gdzie MSI-H była w 15 przypadkach (18,5%), a MSI-L — w 25 przypadkach(30,9%). Zaobserwowano istotną statystycznie korelację między MSI i występowaniem przerzutów w wątrobieoraz przerzutów w mózgu. Znaleźliśmy także tendencję do podwyższonego wystąpienia MSI-H w raku zrazikowym(nieistotne statystycznie).Wnioski. W przeprowadzonych przez nas analizach obecność MSI w rakach piersi wiązała się z krótszym przeżyciemi większą agresywnością (przerzutami do wątroby i mózgu).Introduction. Breast carcinoma is one of the most common malignancies in women, and its carcinogenesis etiologyis still unknown. Loss of MMR function prevents the correction of replicative errors leading to instability of the genome,and can be detected by polymorphisms in micro satellites (1–6 nucleotide repeat sequences). This is knownas microsatellite instability (MSI), and is a hallmark of MMR dysfunction and can thus be used as a marker of MMRdysfunction in colorectal and other malignancies.Material and methods. We studied the presence of MSI in 81 invasive breast cancers and evaluated its relationshipwith patient age, tumor size, tumor type, lymph node metastasis, liver metastasis, brain metastasis, local recurrence,and other. Microsatellite analysis was performed using 10 markers selected for sensitive detection of microsatelliteinstability in breast cancer.Results. MSI was detected in 40 of 81 cases (49.4%), where MSI-H was in 15 cases (18.5%) and MSI-L was in 25 cases(30.9%). A statistically significant correlation was observed between MSI and liver metastasis and brain metastasis. Wealso found a correlation (not statistically significant) between MSI-H and lobular carcinoma.Conclusion. The analyzes performed showed that the presence of MSI in breast cancer was associated with shortersurvival and was more aggressive when metastases to the liver and brain were present

    Landscape of oncoplastic breast surgery across Poland

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    Techniki onkoplastyczne i rekonstrukcyjne stanowią podstawowe narzędzia pracy współczesnych chirurgów piersi. Celem badania było ustalenie rodzajów rekonstrukcji onkoplastycznych przeprowadzanych w ośrodkach leczenia raka piersi w Polsce. Drogą e-mailową rozesłano kwestionariusz zawierający 18 pytań do członków Polskiego Towarzystwa Chirurgii Onkologicznej oraz Polskiego Towarzystwa Chirurgii Plastycznej, Rekonstrukcyjnej i Estetycznej poprzez ich portale internetowe. Liczba pacjentek z rakiem piersi poddawana operacji sięgała od 120 do 904 rocznie w każdym z ośrodków. Wykonywano głównie operacje oszczędzające pierś (breast conserving surgery - BCS) z wyjątkiem jednego ośrodka (zakres 50 – 70%). Jednoczasową rekonstrukcję piersi (immediate breast reconstruction - IBR) wykonywano w 6-42% zabiegów. Najczęstszym rodzajem IBR była dwuetapowa rekonstrukcja z użyciem ekspandera i wszczepieniem implantu lub jednoetapowa rekonstrukcja przy użyciu implantu z lub bez wszczepienia siatki syntetycznej. Najczęściej wykonywanym zabiegiem odroczonej rekonstrukcji piersi (delayed breast reconstruction - DBR) była dwuetapowa rekonstrukcja z użyciem ekspandera i następnie z wszczepieniem implantu. W żadnym z badanych ośrodków nie wykonywano rekonstrukcji z użyciem wolnego płata. W ośrodku chirurgii plastycznej wykonywano rekonstrukcję z wykorzystaniem płata perforatorów głębokich naczyń nabrzusznych dolnych (DIEP). W ośrodkach onkologicznych wykonywano rekonstrukcje z użyciem płatów uszypułowanych. W wybranych ośrodkach stosowano bezkomórkowe macierze skórne (ADM) oraz przeszczep tkanki tłuszczowej. Oceniono wyniki na podstawie opinii pacjentów (patient-reported outcome measures - PROM) oraz powikłania po zabiegach. Nasze wyniki mogą stanowić podstawę do dalszego doskonalenia umiejętności, akredytacji, zbierania danych i audytu, w tym oceny na podstawie opinii pacjentów. Istnieje również pilna potrzeba rozwiązania problemu nierówności w refundacji procedur w różnych państwach Europy.Oncoplastic and reconstructive techniques are essential tools in the armamentarium of contemporary breast surgeons. The aim of the study was to identify oncoplastic reconstructive patterns in breast cancer centers across Poland. A questionnaire of 18 questions was sent by email to the members of the Polish Society of Surgical Oncology and the Polish Society of Plastic, Reconstructive and Esthetic Surgery via their dedicated websites. The numbers of breast cancer patients operated on in each center ranged from 120 to 904 per year. Breast-conserving surgery (BCS) predominated in all but one center (range 50-70%). Immediate breast reconstructions (IBR) accounted for 6-42% of procedures, The most frequent type of IBR was either a two-stage expander followed by a permanent implant or one-stage implant- based with or without synthetic mesh. The most frequent type of delayed breast reconstruction (DBR) was a two-stage expander followed by implant-based reconstruction. None of the surveyed cancer centers performed free flap reconstruction. Deep inferior epigastric perforator (DIEP) flaps were performed in the plastic surgery department. Reconstructions based on pedicled flaps were performed in cancer centers. Acellular dermal matrices (ADM) and fat transfer were used in selected centers. In the clinical scenario of adjuvant radiotherapy, delayed breast reconstruction was favored. The full range of oncoplastic BCS was performed. Patient-reported outcome measures (PROM) and complications were assessed. Our findings can act as a platform for further improvement in skills, certification, data collection and audit, including patient reported expectation measures. There is also an urgent need to address pan-European inconsistencies in procedural reimbursement

    Zastosowanie elektrochemioterapii w leczeniu rozsiewu nowotworów do skóry — pierwsze doświadczenia ośrodka

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    Introduction. Electrochemotherapy (ECT) is an ablation method based on a reversible electroporation combination with concurrent chemotherapy (intravenous administration or directly into the tumour). This method has been used in the treatment of primary skin tumours (carcinomas, melanomas) and secondary malignancies (e.g. breast cancer metastases) which were unfit or unresponsive to a different type of treatment. It is a palliative method aimed at improving the quality of life. Material and methods. Between February and May 2015 seven patients with metastatic breast cancer to the skin and subcutaneous tissue, and one patient with recurrent melanoma in the skin after groin lymphadenectomy, underwent the ECT procedure. Results. For the patients treated by ECT, there were a total of 10 procedures for 50 target lesions. Seven patients underwent one course, one patient received three courses because of extension of the lesions. In 87.5% of the lesions good local effect as a complete or partial remission was observed. Patients remain under close observation and control. Conclusions. The results show that ECT is an effective and safe therapeutic option for the treatment of unresectable skin malignances, especially in the case of prior use of other available methods of cancer treatment.  Wstęp. Elektrochemioterapia (ECT) jest metodą ablacyjną opartą na odwracalnej elektroporacji komórek pod wpływem prądu o wysokim napięciu w połączeniu z jednoczasową iniekcją chemioterapeutyku dożylnie lub do guza. Metoda ta znalazła zastosowanie w leczeniu pierwotnych nowotworów skóry (raki, czerniaki), jak i nowotworów wtórnych (np. z raka piersi) nienadających się lub nieodpowiadających na inny typ leczenia. Jest to metoda paliatywna, mająca na celu poprawę jakości życia oraz zabezpieczenie przed powikłaniami miejscowymi. Materiał i metody. Pomiędzy lutym 2015 r. a majem 2015 r. siedmiu pacjentów z przerzutami raka piersi do skóry i tkanki podskórnej oraz jeden pacjent z rozsiewem czerniaka w okolicy blizny po limfadenektomii pachwinowej poddani zostali zabiegowi elektrochemioterapii. Wyniki. U siedmiu pacjentów zakwalifikowanych do zabiegu elektrochemioterapii wykonano łącznie 10 zabiegów na 50 zmianach docelowych, mierzalnych (target lesions). U siedmiu pacjentów przeprowadzono po jednym zabiegu, u jednego pacjenta, ze względu na rozległość zmian skórnych, zaplanowano trzy zabiegi. W 87,5% zmian zaobserwowano dobry efekt miejscowy pod postacią całkowitej lub częściowej remisji. Pacjenci pozostają pod ścisłą obserwacją i kontrolą. Wnioski. Przedstawione powyżej wyniki udowadniają, iż ECT jest skuteczną i bezpieczną opcją terapeutyczną w leczeniu nieresekcyjnych, powierzchniowo rozsianych zmian nowotworowych, szczególnie w sytuacji wcześniejszego wykorzystania dostępnych metod leczenia onkologicznego.

    Gas-loading apparatus for large-volume high-pressure cell

    No full text
    The Paris-Edinburgh cell (PEC) is a widely used opposed-anvil device for neutron scattering. Since its development, it has been used to study a number of samples loaded as solids or liquids. However, studying gases at room temperature has not yet been possible. Up until now only a few gases could be loaded as liquids, in cryogenic conditions. Thus, it was impossible to study many gases and gas mixtures and also it was difficult to use gases as pressure-transmitting media (PTM). In order to overcome these limitations, a technique that would enable loading of gases into the PEC was required. The work described in this thesis was focused on the design and use of a gas-loading system for the PEC. The challenge of designing such a system comes from the fact that the gases need to be loaded into the gasket at sufficient density in order to achieve any significant pressure during further compression in the cell. This can be achieved by using a separate pressure vessel. Because the whole PEC is too large to be placed inside the vessel, a technique of loading gas into the anvils separated from the rest of the cell had to be devised. Designing the holder for the anvils, which would make this possible, presented a major challenge as it should allow the anvils to be transferred between the vessel and the PEC, with the gasket filled with high-pressure gas. Then it needs to allow further compression of the gasket inside the PEC. The developed system consists of a pressure vessel and a locking clamp for the anvils. The pressure vessel is a closed-end thick-walled cylinder with a top cover which has an opening for a piston. The vessel is placed on the table of a hydraulic press and the piston, sealed by a high-pressure reciprocating seal, is used to transmit the force from hydraulic ram onto the anvils which are held by the clamp and placed inside the vessel. One of the anvils is fixed to the clamp and the other one is supported by spring-loaded latches - the latches engage when the anvils are pushed towards each other. Thus, when the force is applied onto the anvils to compress the gasket, latches lock the anvils in their positions stopping them from retracting and maintaining the gasket compressed after the force is released. The clamp allows the gasket to be filled with the gas and then deformed to seal the compressed gas. The locking mechanism keeps the gasket compressed, which enables the clamp to be transferred from the vessel to the PEC. After the system was built and tested, it was installed at ISIS neutron source (Oxfordshire, UK), where it has been used in several experiments. The first experiment prepared with the gas-loading system was a neutron diffraction study of nitrogen at high pressure. Nitrogen was chosen as a sample material because its high-pressure structural phase diagram is well established. Nitrogen was loaded into the gasket using the gas loader and then it was compressed in increments to 6 GPa in the PEC. β and δ phases of solid nitrogen were clearly seen in the collected neutron diffraction data. The experiment proved the usability of the gas-loading system and verified its expected performance. The second experiment utilizing the gas-loading system was to study singlecrystal and powder samples of sodium chloride (NaCl) and squaric acid (H2C4O4). For these studies argon was used as a PTM, replacing the conventionally used methanol-ethanol mixture (ME). Up until this experiment the highest pressure reported in single-crystal neutron-scattering experiments was 12 GPa. This limit was set by the solidi cation pressure of ME. With argon as the PTM, the samples were compressed to 15 GPa without any damage to the crystals. Another advantage of replacing ME with argon is improved hydrostaticity. The highest pressure that ME remain hydrostatic to is 11 GPa. Compressing beyond this point causes sheer stress acting on the sample which affects the quality of the neutron scattering data manifested in the appearance of peak-broadening in the diffraction patterns. With use of argon, the powder samples have been compressed to 18 GPa while maintaining quasi-hydrostatic pressure conditions, resulting in clean and sharp diffraction patterns without any noticeable peak-broadening.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Gait coordination in overground walking with a virtual reality avatar

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    Little information is currently available on interpersonal gait synchronization in overground walking. This is caused by difficulties in continuous gait monitoring over many steps while ensuring repeatability of experimental conditions. These challenges could be overcome by using immersive virtual reality (VR), assuming it offers ecological validity. To this end, this study provides some of the first evidence of gait coordination patterns for overground walking dyads in VR. Six subjects covered the total distance of 27 km while walking with a pacer. The pacer was either a real human subject or their anatomically and biomechanically representative VR avatar driven by an artificial intelligence algorithm. Side-by-side and front-to-back arrangements were tested without and with the instruction to synchronize steps. Little evidence of spontaneous gait coordination was found in both visual conditions, but persistent gait coordination patterns were found in the case of intentional synchronization. Front-to-back rather than side-by-side arrangement consistently yielded in the latter case higher mean synchronization strength index. Although the mean magnitude of synchronization strength index was overall comparable in both visual conditions when walking under the instruction to synchronize steps, quantitative and qualitative differences were found which might be associated with common limitations of VR solutions

    Topological assessment of gait synchronisation in overground walking groups

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    Walking is one of the fundamental forms of human gross motor activity in which spatiotemporal movement coordination can occur. While considerable body of evidence already exists on pedestrian movement coordination while walking in pairs, little is known about gait control while walking in more complex topological arrangements. To this end, this study provides some of the first evidence of spontaneous gait synchronisation while walking in a group. Nine subjects covered the total distance of 40 km at different speeds while assembled in a three-by-three formation. Two experimental protocols were applied in which the subjects were either not specifically asked to or specifically asked to synchronise their gait. To obtain results representative from the point of view of gait control, the movement coordination was quantified using the indirectly measured vertical component of ground reaction force, based on output from a network of wireless motion monitors. Bivariate phase difference analysis was conducted using wavelet transform, synchronisation strength measures derived from Shannon entropy, and circular statistics. A fundamental relationship describing the influence of the group walking speed on individuals’ pacing frequency was established, showing a positive correlation different from that previously reported for walking in solitude. A positive correlation was found between the average synchronisation strength within a group and group’s walking speed. The most persistent coordination patterns were identified for pedestrians walking front-to-back and side-by-side. Overall, the spontaneous gait synchronisation while walking in a group is relatively weak, well below the levels reported for walking in pairs

    Long-term results of combined treatment of patients with early breast cancer after conserving therapy

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    Introduction: Mastectomy was the most frequently used method of surgical treatment of patients with breast cancer in the Kielce Region. With the opening of the Surgical Oncology Clinic and the Department of Radiotherapy in the Holycross Cancer Centre, a larger number of patients could undergo breast-conserving therapy. Aim of the research: The objective of the study was evaluation of the remote outcome of treatment of patients with breast cancer after conserving therapy. Material and methods: During the period 2001–2005, in the Holycross Cancer Centre, 65 women with early-stage breast cancer underwent breast-conserving therapy. The patients were subjected to combined treatment. The total period of observation was from 105 to 143 months; median 113 months. In statistical analysis the distribution of the investigated variables was examined using the Kolmogorov-Smirnov test and Lillefors test. The significance of the differences between the variables analysed was tested by means of the Mann-Whitney U test. The probability of survival without symptoms of the disease was estimated by the Kaplan-Meier method. The cosmetic outcome was evaluated based on individual medical observations and a questionnaire developed at the Department of Radiotherapy. Results and conclusions : Relapse of the disease was noted in 5 (8%) patients. Local recurrence occurred in 2 (3%) patients. In the analysed group, the 2-, 3-, 5-, and 10-year survival rates without symptoms were 98.5%, 96.9%, 95.4%, and 95.4%, respectively. No statistically significant differences were found between the groups of patients with and without cancer. In the majority of patients, after many-year observation, the cosmetic outcome is good
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