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1.
Ramya Rangarajan 《Reports of Practical Oncology and Radiotherapy》2018,23(1):57-60
Aim
The aim of the study is to evaluate the differences in dosimetry between tandem-ovoid and tandem-ring gynaecologic brachytherapy applicators in image based brachytherapy.Background
Traditionally, tandem ovoid applicators were used to deliver dose to tumor in intracavitary brachytherapy. Tandem-ring, tandem-cylinder and hybrid intracavitary, interstitial applicators are also used nowadays in cervical cancer brachytherapy.Methods and materials
100 CT datasets of cervical cancer patients (stage IB2 – IIIB) receiving HDR application (50 tandem-ovoid and 50 tandem-ring) were studied. Brachytherapy was delivered using a CT-MRI compatible tandem-ovoid (50 patients) and a tandem-ring applicator (50 patients). DVHs were calculated and D2cc was recorded for the bladder and rectum and compared with the corresponding ICRU point doses. The point B dose, the treated volume, high dose volume and the treatment time were recorded and compared for the two applicators.Results
The mean D2cc of the bladder with TR applicator was 6.746 Gy. TO applicator delivered a mean D2cc of 7.160 Gy to the bladder. The mean ICRU bladder points were 5.60 and 5.63 Gy for TR and TO applicator, respectively. The mean D2cc of the rectum was 4.04 Gy and 4.79 Gy for TR and TO applicators, respectively. The corresponding ICRU point doses were 5.10 Gy and 5.66 Gy, respectively.Conclusions
The results indicate that the OAR doses assessed by DVH criteria were higher than ICRU point doses for the bladder with both tandem-ovoid and tandem-ring applicators whereas DVH based dose was lower than ICRU dose for the rectum. The point B dose, the treated volume and high dose volume was found to be slightly higher with the tandem-ovoid applicator. The mean D2cc dose for the bladder and rectum was lower with tandem-ring applicators. The clinical implication of the above dosimetric differences needs to be evaluated further. 相似文献2.
Annamaria Didona Valentina Lancellotta Claudio Zucchetti Bianca Moira Panizza Alessandro Frattegiani Martina Iacco Anna Concetta Di Pilato Simonetta Saldi Cynthia Aristei 《Reports of Practical Oncology and Radiotherapy》2018,23(3):175-182
Background
Intensity-modulated radiotherapy (IMRT) improves dose distribution in head and neck (HN) radiation therapy. Volumetric-modulated arc therapy (VMAT), a new form of IMRT, delivers radiation in single or multiple arcs, varying dose rates (VDR-VMAT) and gantry speeds, has gained considerable attention. Constant dose rate VMAT (CDR-VMAT) associated with a fixed gantry speed does not require a dedicated linear accelerator like VDR-VMAT. The present study explored the feasibility, efficiency and delivery accuracy of CDR-VMAT, by comparing it with IMRT and VDR-VMAT in treatment planning for HN cancer.Methods and materials
Step and shoot IMRT (SS-IMRT), CDR-VMAT and VDR-VMAT plans were created for 15 HN cancer patients and were generated by Pinnacle3 TPS (v 9.8) using 6 MV photon energy. Three PTVs were defined to receive respectively prescribed doses of 66 Gy, 60 Gy and 54 Gy, in 30 fractions. Organs at risk (OARs) included the mandible, spinal cord, brain stem, parotids, salivary glands, esophagus, larynx and thyroid. SS-IMRT plans were based on 7 co-planar beams at fixed gantry angles. CDR-VMAT and VDR-VMAT plans, generated by the SmartArc module, used a 2-arc technique: one clockwise from 182° to 178° and the other one anti-clockwise from 178° to 182°. Comparison parameters included dose distribution to PTVs (Dmean, D2%, D50%, D95%, D98% and Homogeneity Index), maximum or mean doses to OARs, specific dose-volume data, the monitor units and treatment delivery times.Results
Compared with SS-IMRT, CDR-VMAT significantly reduced the maximum doses to PTV1 and PTV2 and significantly improved all PTV3 parameters, except D98% and D95%. It significantly spared parotid and submandibular glands and was associated with a lower Dmean to the larynx. Compared with VDR-VMAT, CDR-VMAT was linked to a significantly better Dmean, to the PTV3 but results were worse for the parotids, left submandibular gland, esophagus and mandible. Furthermore, the Dmean to the larynx was also worse. Compared with SS-IMRT and VDR-VMAT, CDR-VMAT was associated with higher average monitor unit values and significantly shorter average delivery times.Conclusions
CDR-VMAT appeared to be a valid option in Radiation Therapy Centers that lack a dedicated linear accelerator for volumetric arc therapy with variable dose-rates and gantry velocities, and are unwilling or unable to sanction major expenditure at present but want to adopt volumetric techniques. 相似文献3.
Morbidity dynamics in proton–photon or photon radiation therapy for locally advanced prostate cancer
Evgeny V. Khmelevsky Irina N. Kancheli Vladimir S. Khoroshkov Andrey D. Kaprin 《Reports of Practical Oncology and Radiotherapy》2018,23(1):21-27
Aim
This study evaluated the frequency and long-term dynamics of early and late post irradiation damage after proton–photon or photon therapy for locally advanced prostate cancer.Background
The results of a randomized study of proton–photon or photon therapy using several fractionation regimes were analyzed in 272 patients with high and intermediate risk of progression.Materials and methods
Three variants of proton boost fractionation were studied sequentially: 3.0 (8 daily fractions), 4.0 (5 fractions, 3 or 5 fractions/week), and 5.5 (3 fractions, 3 fractions/week) Gy(RBE).Results
A significant decrease in the severity of both acute and late gastrointestinal injuries is achievable with a proton beam. The dynamics of late gastrointestinal and genitourinary toxicity over a 10-year period were generally characterized by a decrease in severity of morbidity by 30% and 15%, respectively.Conclusions
Local irradiation with a fractional dose of 3.0–5.5 Gy(RBE) and a cumulative dose of 28.0–28.8 Gy(RBE) for protons significantly reduces the early and late rectitis severity, but does not reduce the risk of lower urinary tract injuries. Fractionation regimens do not significantly differ in toxicity levels. 相似文献4.
Hamid Shafaei Douk Mahmoud Reza Aghamiri Mahdi Ghorbani Bagher Farhood Mohsen Bakhshandeh Hamid Reza Hemmati 《Reports of Practical Oncology and Radiotherapy》2018,23(2):105-113
Aim
The aim of this study is to evaluate the accuracy of the inverse square law (ISL) method for determining location of virtual electron source (SVir) in Siemens Primus linac.Background
So far, different experimental methods have presented for determining virtual and effective electron source location such as Full Width at Half Maximum (FWHM), Multiple Coulomb Scattering (MCS), and Multi Pinhole Camera (MPC) and Inverse Square Law (ISL) methods. Among these methods, Inverse Square Law is the most common used method.Materials and methods
Firstly, Siemens Primus linac was simulated using MCNPX Monte Carlo code. Then, by using dose profiles obtained from the Monte Carlo simulations, the location of SVir was calculated for 5, 7, 8, 10, 12 and 14 MeV electron energies and 10 cm × 10 cm, 15 cm × 15 cm, 20 cm × 20 cm and 25 cm × 25 cm field sizes. Additionally, the location of SVir was obtained by the ISL method for the mentioned electron energies and field sizes. Finally, the values obtained by the ISL method were compared to the values resulted from Monte Carlo simulation.Results
The findings indicate that the calculated SVir values depend on beam energy and field size. For a specific energy, with increase of field size, the distance of SVir increases for most cases. Furthermore, for a special applicator, with increase of electron energy, the distance of SVir increases for most cases. The variation of SVir values versus change of field size in a certain energy is more than the variation of SVir values versus change of electron energy in a certain field size.Conclusion
According to the results, it is concluded that the ISL method can be considered as a good method for calculation of SVir location in higher electron energies (14 MeV). 相似文献5.
6.
Elham Hosseinzadeh Nooshin Banaee Hassan Ali Nedaie 《Reports of Practical Oncology and Radiotherapy》2018,23(1):39-46
Aim
The aim of this study is to calculate neutron contamination at the presence of circular cones irradiating by 18 MV photons using Monte Carlo code.Background
Small photon fields are one of the most useful methods in radiotherapy. One of the techniques for shaping small photon beams is applying circular cones made of lead. Using this method in high energy photon due to neutron contamination is a crucial issue.Materials and methods
Initially, Varian linac producing 18 MV photons was simulated and after validating the code, various circular cones were also simulated. Then, the number of neutrons, neutron equivalent dose and absorbed dose per Gy of photon dose were calculated along the central axis.Results
Number of neutrons per Gy of photon dose had their maximum value at depth of 2 cm and these values for 5, 10, 15, 20 and 30 mm circular cones were 9.02, 7.76, 7.61, 6.02 and 5.08 (n cm?2 Gy?1), respectively. Neutron equivalent doses per Gy of photon dose had their maximum at the surface of the phantom and these values for mentioned collimators were 1.48, 1.33, 1.31, 1.12 and 1.08 (mSv Gy?1), respectively. Neutron absorbed doses had their maximum at the surface of the phantom and these values for mentioned collimators sizes were 103.74, 99.71, 95.77, 81.46 and 78.20 (μGy/Gy), respectively.Conclusions
As the field size gets smaller, number of neutrons, equivalent and absorbed dose per Gy of photon increase. Also, neutron equivalent dose and absorbed dose are maximum at the surface of phantom and then these values will be decreased. 相似文献7.
Aim
In this study, at different fields, energies and gantry angles, treatment couch and rails dose absorption ratio and treatment couch effect on surface and build-up region doses were examined.Background
It is assumed that radiation attenuation is minimal because the carbon fiber couches have low density and it is not generally accounted for during treatment planning. Consequently, it leads to a major dosimetric mistake.Materials and methods
Solid water phantom was used for relative dose measurement. The measurements were done using a Farmer ion chamber with 0.6 cc volume and a parallel plane ion chamber starting from surface with 1 mm depth intervals at 10 × 10 cm2 field, SSD 100 cm. Measurements were taken for situations where the beams intersect the couch and couch rails.Results
Dose absorption ratio of carbon fiber couch obtained at gantry angle of 180° was 1.52%, 0.69%, 0.33% and 0.25% at different field sizes for 6 MV. For 15 MV, this ratio was 0.95%, 0.27%, 0.20% and 0.05%. The absorption ratio is between 3.4% and 1.22% when the beams intersect with couch rails. The couch effect increased surface dose from 14% to 70% for 6 MV and from 11.34% to 53.03% for 15 MV.Conclusions
The results showed that the carbon fiber couch increased surface dose during posterior irradiation. Therefore, the skin-sparing effect of the high energy beams was decreased. If the effect of couch is not considered, it may cause significant differences at dose which reaches the patient and may cause tissue problems such as erythema. 相似文献8.
Hediye Acun-Bucht Ebru Tuncay Emin Darendeliler Gönül Kemikler 《Reports of Practical Oncology and Radiotherapy》2018,23(4):242-250
Aim
This study aims at examining absolute dose verification of step-and-shoot intensity modulated radiation treatment (IMRT) of prostate and brain patients by use of ion chambers of two different volumes and thermoluminescent detectors (TLD).Background
The volume of the ion chamber (IC) is very important for absolute dose verification of IMRT plans since the IC has a volume average effect. With TLD detectors absolute dose verification can be done measuring the dose of multiple points simultaneously.Materials and methods
Ion chambers FC65-P of volume 0.65 cc and semiflex of volume 0.125 cc as well as TLDs were used to measure the central axis absolute dose of IMRT quality assurance (QA) plans. The results were compared with doses calculated by a treatment planning system (TPS). The absolute doses of off axis points located 2 cm and 4 cm away from the isocenter were measured with TLDs.Results
The measurements of the 0.125 cc ion chamber were found to be closer to TPS calculations compared to the 0.65 cc ion chamber, for both patient groups. For both groups the root mean square (RMS) differences between doses of the TPS and the TLD detectors are within 3.0% for the central axis and points 2 cm away from the isocenter of each axis. Larger deviations were found at the field edges, which have steep dose gradient.Conclusions
The 0.125 cc ion chamber measures the absolute dose of the isocenter more accurately compared to the 0.65 cc chamber. TLDs have good accuracy (within 3.0%) for absolute dose measurements of in-field points. 相似文献9.
Hidekazu Tanaka Takahiro Yamaguchi Kae Hachiya Shingo Kamei Satoshi Ishihara Masahide Hayashi Shinichi Ogawa Hironori Nishibori Satoshi Goshima Masayuki Matsuo 《Reports of Practical Oncology and Radiotherapy》2018,23(1):28-33
Aim
This study aimed to evaluate the treatment result of intensity-modulated radiation therapy (IMRT) in a large number of Japanese patients with prostate cancer.Background
A total of 1091 patients with localized prostate cancer were recruited between March 2006 and July 2014. The patients were stratified into low- (n = 205 [18.8%]), intermediate- (n = 450 [41.2%]), high- (n = 345 [31.6%]), and very high-risk (n = 91 [8.3%]) groups according to the National Comprehensive Cancer Network classification. All patients were irradiated via IMRT at a dose of 74–78 Gy with or without androgen-deprivation therapy. The mean follow-up period was 50 months (range, 2–120 months).Results
The biochemical failure-free rate (BFFR), the clinical failure-free rate, and the overall survival rate at the 5-year follow-up for all patients was 91.3%, 96.2%, and 99.1%, respectively. In univariate analysis, the prostate-specific antigen (PSA) levels (≤20 vs. >20 ng/ml) were significantly correlated with BFFR. A trend toward higher BFFR was noted in patients with a Gleason score (GS) of ≤7 than in patients with GS ≥8. In multivariate analysis, only PSA (≤20 vs. >20 ng/ml) was significantly correlated with BFFR. The cumulative incidence rate of gastrointestinal and genitourinary toxicity (≥grade 2) at the 5-year follow-up was 11.4% and 4.3%, respectively.Conclusions
The findings of this study indicate that IMRT is well tolerated and is associated with both good long-term tumor control and excellent outcomes in patients with localized prostate cancer. 相似文献10.
Avinash H. Udayashankar Shibina Noorjahan Nirmala Srikantia K. Ravindra Babu Sandeep Muzumder 《Reports of Practical Oncology and Radiotherapy》2018,23(4):233-241
Aim
To identify the most reproducible technique of patient positioning and immobilization during pelvic radiotherapy.Background
Radiotherapy plays an important role in the treatment of pelvic malignancies. Errors in positioning of patient are an integral component of treatment. The present study compares two methods of immobilization with no immobilization with an aim of identifying the most reproducible method.Materials and methods
65 consecutive patients receiving pelvic external beam radiotherapy were retrospectively analyzed. 30, 21 and 14 patients were treated with no-immobilization with a leg separator, whole body vacuum bag cushion (VBC) and six point aquaplast immobilization system, respectively. The systematic error, random error and the planning target volume (PTV) margins were calculated for all the three techniques and statistically analyzed.Results
The systematic errors were the highest in the VBC and random errors were the highest in the aquaplast group. Both systematic and random errors were the lowest in patients treated with no-immobilization. 3D Systematic error (mm, mean ± 1SD) was 4.31 ± 3.84, 3.39 ± 1.71 and 2.42 ± 0.97 for VBC, aquaplast and no-immobilization, respectively. 3D random error (mm, 1SD) was 2.96, 3.59 and 1.39 for VBC, aquaplast and no-immobilization, respectively. The differences were statistically significant between all the three groups. The calculated PTV margins were the smallest for the no-immobilization technique with 4.56, 4.69 and 4.59 mm, respectively, in x, y and z axes, respectively.Conclusions
Among the three techniques, no-immobilization technique with leg separator was the most reproducible technique with the smallest PTV margins. For obvious reasons, this technique is the least time consuming and most economically viable in developing countries. 相似文献11.
12.
Claudio Farías-Valenzuela Cristian Pérez-Luco Rodrigo Ramírez-Campillo Cristian Álvarez Mauricio Castro-Sepúlveda 《Revista espa?ola de geriatría y gerontología》2018,53(3):141-144
Background
Handgrip strength (HS) and peak oxygen consumption (Vo2peak) are powerful predictors of cardiovascular risk, although it is unknown which of the two variables is the better predictor.Aim
The objective of the following study was to relate HS and Vo2peak to cardiovascular risk markers in older Chilean women.Methods
Physically active adult women (n = 51; age, 69 ± 4.7 years) participated in this study. The HS and Vo2peak were evaluated and related to the anthropometric variables of body mass, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist ratio (WR), and waist height ratio (WHR), as well as with the cardiovascular variables systolic (SBP) and diastolic (DBP) and cardiac recovery in one minute (RHR1). A multilinear regression model was used for the analysis of the associated variables (P < .05).Results
The cardiovascular risk markers associated (P < .05) with the handgrip strength of the dominant limb (HSDL) were body mass, BMI, WR, and WHR. The handgrip strength of the non-dominant limb (HSNDL) was associated with body mass. Vo2peak was associated with body mass, BMI, HC and RHR1. The multilinear regression model showed a value of r = 0.43 in HSDL, r = 0.39 in HSNDL and r = 0.69 in peak Vo2.Conclusion
Although HS and Vo2peak were related to cardiovascular risk markers, Vo2peak offers greater associative power with these cardiovascular risk factors. 相似文献13.
Oriol Turró Garriga Sílvia Farrés Costa Albert Pérez Terré Pau Batlle Amat 《Revista espa?ola de geriatría y gerontología》2018,53(4):196-201
Introduction
The care of dependent persons is arduous, and requires time, energy, and physical effort on the part of caregivers. Personal characteristics, such as the sense of coherence (SOC), can influence the perceived burden and care giving.Objective
To determine the impact of SOC on the perceived burden and to determine if these characteristics are associated with adherence to a psycho-educational program for informal caregivers.Material and method
Prospective observational study of caregivers of dependent persons participating in the ‘School of Caregivers’, a psycho-educational program for family and paid caregivers. An analysis was made of the SOC-13 items and the results of the Zarit Burden Interview. The relationship between the SOC and the adherence to the program (≥ 50% sessions) was also analysed.Results
The study included 96 participants, with 71.9% family carers. The higher burden was associated with a lower SOC meaningfulness factor (β = –0.388; P = .002), and to be a relative vs. paid carer (β = –0.300; P = .010). Just over half (52.1%) of carers completed 50% or more sessions, and in the case of the relatives, this adherence increased by higher SOC (OR: 1.1, P = .034), and lower burden (OR: 0.95, P = .032). The lack of adherence of paid caregivers was not associated with any of the analysed variables.Conclusions
The sense of coherence and mainly the meaning, is a characteristic to take into account for the adaptation of interventions in caregivers and provide them with greater equity working more on the people who need it the most (lower SOC and greater burden). 相似文献14.
Cristina Buiza Javier Yanguas Amaia Zulaica Iván Antón Enrique Arriola Alvaro García 《Revista espa?ola de geriatría y gerontología》2018,53(4):208-212
Introduction
Adaptation and validation to the Basque language of tests to assess advanced cognitive impairment is a not covered need for Basque-speaking people. The present work shows the validation of the Basque version of the Severe Mini Mental State Examination (SMMSE).Material and methods
A total of 109 people with advanced dementia (MEC < 15) took part in the validation study, and were classified as GDS 5-7 on the Geriatric Depression Scale (GDS). All participants were Spanish-Basque bilingual.Results
It was shown that SMMSE-eus has a high internal consistency (alpha = 0.92), a good test-retest reliability (r = 0.88; P < .01), and a high inter-rater reliability (CCI = 0.99; P < .00) for the overall score, as well as for each item.Conclusions
Both the high internal consistency and inter-rater reliability, and to a lesser extent, test-retest reliability, made the SMMSE-eus a valid test for the brief assessment of cognitive status in people with advanced dementia in Basque-speaking people. For this reason, the SMMSE-eus is a usable and reliable alternative for assessing Basque-speaking people in their mother-tongue, or preferred language. 相似文献15.
Francieli Chassot Tarcieli Pozzebon Venturini Fernanda Baldissera Piasentin Janio Morais Santurio Terezinha Inez Estivalet Svidzinski Sydney Hartz Alves 《Revista iberoamericana de micología》2019,36(1):44-47
Background
Candida parapsilosis may acquire resistance to echinocandins, a fact that prompts the search for new therapeutic options.Aims
The present study aimed to evaluate the in vitro activity of antifungal agents, alone and in combination, against four groups of C. parapsilosis strains: (1) echinocandin-susceptible (ES) clinical isolates (MIC ≤ 2 μg/ml), (2) anidulafungin-resistant strains (MIC ≥ 8 μg/ml), (3) caspofungin-resistant strains (MIC ≥ 8 μg/ml), and (4) micafungin-resistant strains (MIC ≥ 8 μg/ml).Methods
Antifungal interactions were evaluated by a checkerboard micro-dilution method. The determination of the MIC to each drug for every isolate according to the Clinical and Laboratory Standards Institute documents M27 (2017) and M60 (2017) was also done.Results
The echinocandins-resistant (ER) strains showed higher MICs to the tested antifungals than the ES strains, except for amphotericin B, for which the ER groups remained susceptible.Conclusions
Most combinations showed indifferent interactions. The use of monotherapy still seems to be the best option. As resistance to echinocandins is an emergent phenomenon, further studies are required to provide clearer information on the susceptibility differences between strains to these antifungal agents. 相似文献16.
Karla Berenice Carrazco-Peña Katia Farías-Moreno Benjamín Trujillo-Hernández 《Revista espa?ola de geriatría y gerontología》2018,53(1):23-25
Objective
To determine the frequency of successful aging (SA) and its relationship with frailty in an elderly population.Material and methods
An analytical cross-sectional study of subjects ≥60 years of age seen as outpatients in a general hospital. Successful aging was defined as scores of ≥ 90 in the Barthel index and ≤ 2 in the Pfeiffer test. Frailty was determined using the Fried criteria.Results
The study included 400 subjects (272 women and 128 men), with a mean age of 71.6 ± 8.2 years. The SA frequency was 40.4%. frail status was statistically higher in non-successful aging subjects than in SA subjects (161.7 versus 7.9%; P<.001). Women were more frequently frail, while being a pensioner/retired and married were associated less frequently with frailty.Conclusions
Successful aging is associated with a lower level of frailty. 相似文献17.
Vanessa Blanco María Adelina Guisande María Teresa Sánchez Patricia Otero Lara López Fernando Lino Vázquez 《Revista espa?ola de geriatría y gerontología》2019,54(1):19-26
Introduction
Most of existing work on burden among family caregivers has methodological sample constraints. Moreover, there is contradictory information regarding sociodemographic variables, especially those related to care, clinical variables, and burden. Few studies have analysed the self-esteem and personality characteristics as correlates of burden. In this study, an analysis is performed on the prevalence of burden among family caregivers and the relationship with their sociodemographic, care-related, and clinical characteristics.Materials and methods
The study consisted of a randomly selected sample of 294 family caregivers (mean age 55.3 years, 89.8% women) from the Autonomous Region of Galicia, Spain. Trained psychologists assessed the presence of burden via the Zarit Caregiver Burden Interview (CBI). Information was also collected on sociodemographic, care-related variables, social support, personality characteristics, and self-esteem.Results
More than half (55.4%) of the surveyed caregivers exhibited burden (CBI > 24), with mean score of 27.3 (SD = 13.3). Not being employed outside the home and having higher scores in neuroticism were associated with a greater probability of presenting with burden, while being older and having higher social support were associated with a lower risk.Conclusions
A significant number of caregivers suffered from burden in the current study. Psychotherapeutic interventions need to be developed for those who are already suffering from burden, as well as prevention strategies for those who have not yet developed it. 相似文献18.
Sandeep Kumar Vishwakarma Avinash Bardia L. Chandrakala Sana Arshiya Syed Ameer Basha Paspala Vishnupriya Satti Aleem Ahmed Khan 《Tissue & cell》2017,49(6):638-647
Introduction
Progress in understanding pathophysiological mechanisms and the development of targeted regenerative strategies have been hampered by the lack of predictive disease models, specifically for the conditions to which affected cell types are inaccessible. The present study has aimed to unearth the role of valproic acid (VPA) and mild hypothermia (MH) as promising strategy to enhance the neuroprotective mechanisms in undifferentiated and differentiated human neural precursor cells (hNPCs) against ethanol-induced damage.Methods
5 mM VPA alone or in combination with MH (33 °C) was used to prevent the damage in proliferating and differentiating hNPCs. CD133 + ve enriched hNPCs were cultured in vitro and exposed to 1 M chronic ethanol concentration for 72 h and followed by VPA and MH treatment for 24 h. Morphometric analysis was performed to identify changes in neurospheres development and neuronal cell phenotypes. Flow cytometry and RT-qPCR analysis was performed to investigate alterations in key molecular pathways involved in cell survival and signaling.Results
Combination of VPA with MH displayed higher proportion of neuronal cell viability as compared to single treatment. Combination treatment was most effective in reducing apoptosis and reactive oxygen species levels in both the undifferentiated and differentiated hNPCs. VPA with MH significantly improved neuronal cell phenotype, active chromatin modeling, chaperon and multi-drug resistant pumps activity and expression of neuronal signaling molecules.Conclusion
The study provided an efficient and disease specific in vitro model and demonstrated that combined treatment with VPA and MH activates several neuroprotective mechanisms and provides enhanced protection against ethanol-induced damage in cultured undifferentiated and differentiated hNPCs. 相似文献19.
Blanca Rosales-Acosta Aarón Mendieta Clara Zúñiga Joaquín Tamariz César Hernández Rodríguez José Antonio Ibarra-García Lourdes Villa-Tanaca 《Revista iberoamericana de micología》2019,36(1):1-8
Background
The enzyme 3-hydroxy-3-methylglutaryl coenzyme A reductase (Hmgr) catalyzes the synthesis of mevalonate, a key compound for the synthesis of cholesterol in humans and ergosterol in fungi. Since the Hmgr enzymes of Saccharomyces cerevisiae, Schizosaccharomyces pombe and Candida glabrata are similar to the Hmgr enzymes of mammals, fungal Hmgr enzymes have been proposed as a model for studying antifungal agents.Aims
To examine the correlation between inhibiting Um-Hmgr enzyme and the viability, sterols synthesis and mating in Ustilago maydis.Methods
Using in silico analysis, the ORF codifying for Um-Hmgr was identified and the protein characteristics were deduced. The effect of the competitive inhibitors of Um-Hmgr on the viability of this basidiomycota, the synthesis of its sterols, and its mating were evaluated.Results
The Umhmgr gene (XP_011389590.1) identified putatively codifies a protein of 1443 aa (ca. MW = 145.5 kDa) that has a possible binding domain in the endoplasmic reticulum (ER) and high identity with the Hmgr catalytic domain of humans and other yeasts. The inhibition of Um-Hmgr caused a decrease of viability and synthesis of sterols, and also the inhibition of mating. The activity of Um-Hmgr is mainly located in the membrane fraction of the fungus.Conclusions
Given our results we believe U. maydis is a valid model for studying synthetic inhibitors with lipid-lowering or antifungal activity. Additionally, we propose the Hmgr enzyme as an alternative molecular target to develop compounds for treating both phytopathogenic and pathogenic human fungi. 相似文献20.
Aparna Gangopadhyay 《Reports of Practical Oncology and Radiotherapy》2018,23(3):228-231