Significant Doses Research Articles

Incidence of Oral Complaints Following Radiotherapy for Treatment of Oral Cancer

Radiation therapy is an important component in management of oral cancer. As a result, various uninvolved structures like salivary glands, oral , dentition, and jaws receive significant doses of radiation. Radiotherapy for oral cancer typically involves total doses of 6,000–7,000 , delivered in daily fractions over 6–7 weeks and is known to cause a number of oral complications. These include oral , oral pain, , increased risk of dental caries, reduced mouth opening, and . The aim of the study isto evaluate and identify the incidence rates of oral complaints following radiotherapy for oral cancer. Data samples required for study were taken from hospital records. All the collected data were cross verified and compiled together in sheet. Compiled data were statistically with help of SPSS software. In this study, a total of 51 patients of oral cancer underwent radiotherapy as a part of their treatment regimen. Higher percentage of patients reported back with no oral complaints of 58.82%. With an increase in age group, more patients had oral complaints after radiotherapy treatment, with p value of 0.114. More males had oral complaints compared to female patients with p value of 0.424. Within the limitations, it is significant that the maximum number of patients who underwent radiotherapy returned without any oral complaints.

Catalase T-Deficient Fission Yeast Meiocytes Show Resistance to Ionizing Radiation.

Environmental stress, reactive oxygen species (ROS), or ionizing radiation (IR) can induce adverse effects in organisms and their cells, including mutations and premature aging. DNA damage and its faulty repair can lead to cell death or promote cancer through the accumulation of mutations. Misrepair in germ cells is particularly dangerous as it may lead to alterations in developmental programs and genetic disease in the offspring. DNA damage pathways and radical defense mechanisms mediate resistance to genotoxic stresses. Here, we investigated, in the fission yeast Schizosaccharomyces pombe, the role of the H2O2-detoxifying enzyme cytosolic catalase T (Ctt1) and the Fe2+/Mn2+ symporter Pcl1 in protecting meiotic chromosome dynamics and gamete formation from radicals generated by ROS and IR. We found that wild-type and pcl1-deficient cells respond similarly to X ray doses of up to 300 Gy, while ctt1∆ meiocytes showed a moderate sensitivity to IR but a hypersensitivity to hydrogen peroxide with cells dying at >0.4 mM H2O2. Meiocytes deficient for pcl1, on the other hand, showed a resistance to hydrogen peroxide similar to that of the wild type, surviving doses >40 mM. In all, it appears that in the absence of the main H2O2-detoxifying pathway S. pombe meiocytes are able to survive significant doses of IR-induced radicals.

Fibroblasts from Retinoblastoma Patients Show Radiosensitivity Linked to Abnormal Localization of the ATM Protein

ABSTRACT Purpose/Aim of the study Retinoblastoma (Rb) is a rare form of pediatric cancer that develops from retina cells. Bilateral and some unilateral forms of Rb are associated with heterozygous germline mutations of the (retinoblastoma 1) RB1 gene. RB1 mutations are also associated with a significant risk of secondary malignancy like head and neck tumors. Hence, to date, even if Rb patients are less subjected to radiotherapy to treat their primary ocular tumors, their healthy tissues may be exposed to significant doses of ionizing radiation during the treatment against their secondary malignancies with a significant risk of adverse tissue reactions (radiosensitivity) and/or radiation-induced cancer (radiosusceptibility). However, the biological role of the Rb protein in response to radiation remains misunderstood. Since the ataxia telangiectasia mutated (ATM) protein is a key protein of radiation response and since untransformed skin fibroblasts are a current model to quantify cellular radiosensitivity, we investigated here for the first time the functionality of the ATM-dependent signaling and repair pathway of the radiation-induced DNA double-strand breaks (DSB) in irradiated skin fibroblasts derived from Rb patients Materials and methods The major biomarkers of the DSB repair and signaling, namely clonogenic cell survival, micronuclei, nuclear foci of the phosphorylated forms of the X variant of the H2A histone (γH2AX), the phosphorylated forms of the ATM protein (pATM) and the meiotic recombination 11 nuclease (MRE11) were assessed in untransformed skin fibroblasts derived from three Rb patients. Results Skin fibroblasts from Rb patients showed significant cellular radiosensitivity, incomplete DSB recognition, delay in the ATM nucleo-shuttling and exacerbated MRE11 nuclease activity. Treatment with statin and bisphosphonates led to significant complementation of these impairments. Conclusions Our findings strongly suggest the involvement of the ATM kinase in the radiosensitivity/radiosusceptibility phenotype observed in Rb cases.

Radiation hardness characterization of LKH-5 scintillating glass

Radiation hardness is an important property to examine in scintillators to help determine their expected lifetime in application cases where significant radiation dose is expected. Industrial imaging systems using 9 MV linear accelerators for x-ray radiography are one such application where significant radiation doses are expected to the scintillators used. Cadmium tungstate scintillators (CWO) and Thallium doped Cesium Iodide scintillators (CsI(Tl)) are used in some high energy cargo x-ray radiography systems. However, CWO has a high manufacturing cost for adequately uniform crystals and CsI(Tl) does not have sufficient radiation hardness. LKH-5 glass is being investigated as a potential low cost replacement for CWO and CsI(Tl). In this experiment 36 samples of a terbium doped silicate glass called LKH-5 were irradiated at doses up to 5 MRad using a 9 MV linear accelerator, and the change in their transmission properties was observed. The glass was discovered to be a radiation hard glass due to the relatively small change in the transmission of the glass: less than 3% per cm at its emission peak of 550 nm and 5 MRad. This is similar to CWO which has a reported reduction in transmitted light of 2% per cm at 5 MRad and the emission peak of 475 nm and better than CsI(Tl) which is reported to have a reduction in transmitted light of 5% per cm at the emission peak of 550 nm and 4.2 MRad dose. Furthermore, an annealing procedure is described that returned the transmission of the glass to pre-irradiation values.

Real-world dosimetric comparison between CyberKnife SBRT and HDR brachytherapy for the treatment of prostate cancer

PurposeHigh-dose-rate (HDR) brachytherapy (BRT) and stereotactic body radiotherapy (SBRT) are currently the two treatment options for definitive radiotherapy of prostate cancer, employing extreme hypofractionation. There are only very few studies comparing their dosimetry, all using computed tomography for treatment planning. We present here a real-word dosimetric comparison between SBRT and ultrasound-based virtual HDR-BRT, with both imaging modalities coming from the same patient. Methods and MaterialsPatients with prostate cancer on a prospective trial evaluating the toxicity of robotic-based SBRT were treated to a total dose of 35 Gy in 5 fractions. Fifteen patients were included in this analysis. During ultrasound-based fiducial implantation, a three-dimensional data set as in real HDR-BRT procedure was acquired. Virtual HDR-BRT plans were generated and various organs at risk and prostate dosimetric parameters were evaluated. ResultsConcerning prostate, SBRT achieved significant higher D98, V35 Gy, and V37.5 Gy coverage, whereas virtual HDR-BRT achieved significant higher intratumoral doses reflected in the V42 Gy and V52.5 Gy. Rectal Dmax, V36 Gy, and V29 Gy were significantly lower for HDR-BRT with no difference as for V18 Gy. SBRT was significantly inferior regarding bladder dosimetry (Dmax, V36 Gy, V18 Gy), whereas urethra Dmax and V44 Gy where significantly higher at the expense of HDR-BRT. ConclusionsHDR-BRT is superior regarding rectum and bladder dosimetry, with SBRT being superior relative to urethra dosimetry. A randomized study is warranted to define the best extreme hypofractionated modality.

A Confession for the End.

A Confession for the End.

Weight of the thyroid, adrenal glands, and the liver of white rats in the conditions of hyperthyroidism: the possibility of applying indices changes as screening-markers for determining body status effected by organic and inorganic iodine.

Despite the available information on the interaction between the thyroid gland activity and that of the adrenal glands, and the liver involvement in their hormones metabolism, the study of the connection existing between these organs in hyperthyroidism is still incomplete. Changes in the weight indices values of the thyroid and adrenal glands and the liver of 90 non-linear white male rats were studied. Animals received histologically verified minimally active (21 μg iodine per kg body weight), moderate (50 μg iodine per kg body weight), and significant (100 μg iodine per kg body weight) doses of organic and inorganic iodine during 30 days under the model hyperthyroidism conditions. It was found that consumption of organic and inorganic iodine at a minimal dose approximates the digital values of adrenal gland and those of the liver of the intact animals. Consumption of a moderate organic iodine dose is accompanied by a decrease in the previously achieved values of the thyroid weight index by 17.28%, and the increase in the liver weight index by 19.66%. When consuming a moderate amount of inorganic iodine, the largest change in the values achieved was the liver weight index which increased by 13.76%. Consumption of organic and inorganic iodine compounds in a significant dose is accompanied by further changing in the studied parameters. When consuming organic iodine the thyroid weight index grows by 10.44%, that of the adrenal glands – by 13.33%, the liver – by 34.52%. Сonsuming of inorganic iodine is accompanied by a rapid increase in the thyroid glands weight index by 21.25%, that of the liver – by 34.31%. The established indicates the existence of functional communication between the studied organs; the effect depends on the chemical nature and dose of iodine consumed. The existing functional dependence gives grounds to apply changes in the weight index of the thyroid gland, adrenal glands and the liver as screening-markers to determine the body’s condition in hyperthyroidism.

Staff radiation dose and estimated risk in an interventional radiology department

In interventional radiology attendant staff can be exposed to significant doses from the radiation scattered from the patient, giving rise to heterogeneous energy distribution, exposure occurring over extended periods of time. Protection of staff is a prime concern, also including reducing the risk of carcinogenesis. With only limited published studies available, as in for instance in regard to lens opacifications, further evaluation of staff exposures and assessment of radiation protection techniques and measures are crucial. Present study has sought to evaluate staff radiation exposure in a radiology department that performs interventional procedures. Annual occupational exposures were obtained for 32 personnel (6 females and 26 males) in a radiology department at a tertiary hospital. Personal dose equivalent Hp (d) was measured in terms of Hp (0.07) (shallow dose) and Hp (10) (deep dose). The measurements were made over a period of two consecutive years, 2017 and 2018, use being made of TLD-100 thermoluminescent dosimeters. In units of mSv, the corresponding average annual dose equivalent and range for Hp (10) and Hp (0.07) were 4.6 ± 7.0 (0.1–25.5) and 5.1 ± 7.3 (0.1–25.5). Notably, 16% of staff received doses that were greater than the annual dose limit. Since Hp (10) offers a conservative evaluation of effective dose, evaluation of the working environment is necessary in seeking to ensure dose values remain below annual dose limits.

Occupational and ambient radiation exposures from Lu-177 DOTATATE during targeted therapy

Lutetium-177 (DOTATATE) (177Lu; T1/2 6.7 days), a labelled β− and Auger-electron emitter, is widely used in treatment of neuroendocrine tumours. During performance of the procedure, staff and other patients can potentially receive significant doses in interception of the gamma emissions [113 keV (6.4%) and 208 keV (11%)] that are associated with the particle decays. While radiation protection and safety assessment are required in seeking to ensure practices comply with international guidelines, only limited published studies are available. The objectives of present study are to evaluate patient and occupational exposures, measuring ambient doses and estimating the radiation risk. The results, obtained from studies carried out in Riyadh over an 11 month period, at King Faisal Specialist Hospital and Research Center, concerned a total of 33 177Lu therapy patients. Patient exposures were estimated using a calibrated Victoreen 451P survey meter (Fluke Biomedical), for separations of 30 cm, 100 cm and 300 cm, also behind a bed shield that was used during hospitalization of the therapy patients. Occupational and ambient doses were also measured through use of calibrated thermoluminescent dosimeters and an automatic TLD reader (Harshaw 6600). The mean and range of administered activity (in MBq)) was 7115.2 ± 917.2 (4329–7955). The ambient dose at corridors outside of therapy isolation rooms was 1.2 mSv over the 11 month period, that at the nursing station was below the limit of detection and annual occupational doses were below the annual dose limit of 20 mSv. Special concern needs to be paid to comforters (carers) and family members during the early stage of radioisotope administration.

Some Biological Parameters of Eisenia fetida (Savigny, 1826) in Pesticide-Applied Vermicompost

The objective of this study was to determine some biological parameters of red California worm (Eisenia fetida) in pesticides applied vermicompost. The study conducted under in-vitro conditions, as Randomized Block Design with five raplications. Commonly used Granland®, Demond® and Safacol® pesticides in Muş province (Turkey) were used as treatments. The temperature and humidity ratio for the experiment were 20-29°C and 70 to 90%, respectively. The experiments were resumed until the young worms hatched from a cocoon reproduced cocoons again. For investigating the effect of the treatments on specific features One-Way Analysis of Variance (One-way ANOVA) and for determining of different groups TUKEY Multiple Comparison Test were used. Variance analysis indicated that there was no statistically differences among fungicide doses in terms of worm weight (P=0.113); however, there were differences in terms of insecticide and herbicide doses (P=0.000). It was detected that there were significant differences among pesticide doses in respect to the cocoon and worm numbers (P=0.000).

Results of the clinical evaluation of the low-dose protocols of the digital linear tomography of the chest

High levels of tuberculosis morbidity in the Russian Federation lead to the extensive use of X-ray diagnostics for the tuberculosis screening and assessment of the effectiveness of treatment. Digital radiography and computed tomography are traditionally used for the diagnostics of tuberculosis. These methods are associated with significant drawbacks: low specificity for radiography, high costs per examination, significant patient doses, and limited availability for computed tomography. As an additional method for the assessment of the effectiveness of the tuberculosis treatment it is possible to use linear tomography performed on the digital X-ray units. The aim of the current study was to evaluate the possibility of utilization of the digital linear tomography for the control of the effectiveness of tuberculosis treatment in a dedicated antitubercular medical facility. The study was divided in two stages. The first stage was aimed at the assessment of the diagnostic image quality of the digital linear tomograms obtained using the previously developed low-dose imaging protocols. Image quality assessment was performed using an anthropomorphic chest phantom and dedicated imitators of the lung lesions. Image quality was assessed by the experts (radiologists) based on the developed image quality criteria. Results of the first stage of the study indicate that all low-dose protocols allow obtaining images with at least acceptable image quality. Hence it was possible to propose low-dose protocols for clinical evaluations. The second stage of the study was performed as a prospective cohort survey aimed at the evaluation of the structure of X-ray examinations, patient doses and clinical image quality of the digital linear tomograms in antitubercular early treatment center. The cohort survey included two patient samples, uniform by age and gender composition, anthropometric characteristics and structure of diagnosis. One of the samples was imaged using standard (vendor) digital linear protocols, other – using the proposed low-dose protocols. Dose data collection (measurement of dose-area product and subsequent calculation of effective dose) and expert image quality assessment was performed for each patient. The results of the second stage of the study indicate that the use of the low-dose protocols allow reducing the patient effective doses per examination up to a factor of 6–8 (0.56 – 5.9 mSv for standard protocols; 0.2 – 1.15 mSv for low-dose protocols) due to the reduction in tube current-time product (126 mean mAs and 11 mean mAs, respectively). The dose reduction is accompanied by the reduction in the image quality of the linear tomograms (from “excellent” or “good” for standard protocols to “acceptable” for low-dose protocols). However, that dose not hinder the conclusion decision and identification of pathologies. Results of the study indicate that digital linear tomography can be used for the evaluation of the dynamics of the pathological process in the lungs with the previously defined localization of the pathology. The presented low-dose protocols were implemented into radiological practice of the antitubercular early treatment center. Currently, the proposed low-dose protocols are under evaluation for the large-scale study on the base of general practice hospitals

The Crystallinity of Apatite in Contact with Metamict Pyrochlore from the Silver Crater Mine, ON, Canada

The purpose of this work is to evaluate the long-term effects of radiation on the structure of naturally occurring apatite in the hope of assessing its potential for use as a solid nuclear waste form for actinide sequestration over geologically relevant timescales. When a crystal is exposed to radioactivity from unstable constituent atoms undergoing decay, the crystal’s structure may become damaged. Crystalline materials rendered partially or wholly amorphous in this way are deemed “partially metamict” or “metamict” respectively. Intimate proximity of a non-radioactive mineral to a radioactive one may also cause damage in the former, evident, for example, in pleochroic haloes surrounding zircon inclusions in micas. Radiation damage may be repaired through the process of annealing. Experimental evidence suggests that apatite may anneal during alpha particle bombardment (termed “self-annealing”), which, combined with a low solubility in aqueous fluids and propensity to incorporate actinide elements, makes this mineral a promising phase for nuclear waste storage. Apatite evaluated in this study occurs in a Grenville-aged crustal carbonatite at the Silver Crater Mine in direct contact with U-bearing pyrochlore (var. betafite)—a highly radioactive mineral. Stable isotope analyses of calcite from the carbonatite yield δ18O and δ13C consistent with other similar deposits in the Grenville Province. Although apatite and betafite imaged using cathodoluminescence (CL) show textures indicative of fracture-controlled alteration, Pb isotope analyses of betafite from the Silver Crater Mine reported in previous work are consistent with a model of long term Pb loss from diffusion, suggesting the alteration was not recent. Thus, it is interpreted that these minerals remained juxtaposed with no further metamorphic overprint for ≈1.0 Ga, and therefore provide an ideal opportunity to study the effects of natural, actinide-sourced radiation on the apatite structure over long timescales. Through broad and focused X-ray beam analyses and electron backscatter diffraction (EBSD) mapping, the pyrochlore is shown to be completely metamict—exhibiting no discernible diffraction associated with crystallinity. Meanwhile, apatite evaluated with these methods is confirmed to be highly crystalline with no detectable radiation damage. However, the depth of α-decay damage is not well-understood, with reported depths ranging from tens of microns to just a few nanometers. EBSD, a surface sensitive technique, was therefore used to evaluate the crystallinity of apatite surfaces which had been in direct contact with radioactive pyrochlore, and the entire volume of small apatite crystals whose cores may have received significant radiation doses. The EBSD results demonstrate that apatite remains crystalline, as derived from sharp and correctly-indexed Kikuchi patterns, even on surfaces in direct contact with a highly radioactive source for prolonged periods in natural systems.

Estimation of available epinephrine dose in expired and discolored autoinjectors via quantitative smartphone imaging.

Epinephrine autoinjectors (EAIs) are important first aid medications for treating anaphylaxis. A 10-fold price increase over the past 12years and evidence that expired EAIs may still contain significant doses of available epinephrine have motivated interest in the efficacy of expired EAIs as treatments of last resort. Degradation of expired EAIs, which can be caused by improper storage conditions, results in various degrees of discoloration of the epinephrine solution. Previous studies have determined that significant epinephrine remains available in expired EAIs, but these have only considered EAIs that show no discoloration. Here, we investigate the potential for colorimetric estimation of available epinephrine dose based on the degree of discoloration in expired EAIs. The correlation of available epinephrine dose and time since expiration date was poor (r = - 0.37), as determined by an industry standard UHPLC protocol. Visible absorbance of the samples integrated across the range 430-475nm correlated well with available epinephrine dose (r= - 0.71). This wavelength corresponds to the blue channel of a typical smartphone camera Bayer filter. Smartphone camera images of the EAI solutions in various illumination conditions were analyzed to assign color indices representing the degree of discoloration. Color index of the samples showed similar correlation (|r| > 0.7) with available epinephrine dose as that of visible spectrophotometry. Smartphone imaging colorimetry is proposed as a potential point-of-use epinephrine dose estimator for expired and degraded EAIs. Graphical abstract.

Radon Measurements in Bottled Waters in Greece

Underground waters pass through various types of rocks, which may contain radium and uranium isotopes in such concentrations and chemical forms that could be diluted in the water body. Thus it is possible to contain significant quantities of these radioisotopes such as radium (226Ra), which decays producing a series of alpha and beta emitters that remain in the water. Among them, radon (222Rn) and isotopes of polonium (214Po and 218Po) contribute to significant doses. In this work, we measured radium/radon concentration levels in bottled waters commercially available in Greece. Samples were concentrated by a factor of 20-100, in order to obtain more accurate results, because in the majority of the samples the concentrations measured initially were very low. To measure the radioactivity concentrations, 10 mL of concentrated sample were added to 10 mL of scintillation cocktail in a 20 mL plastic vial and then were counted with a liquid scintillation analyzer. The results show that radium/radon concentrations of the bottled waters range from 7-70 mBq/L.

In vitro response and gene expression of human retinal Müller cells treated with different anti-VEGF drugs

In the past decade, anti-vascular endothelial growth factor (VEGF) therapy has become more popular and the standard of care for several retinal diseases including exudative age-related macular degeneration (AMD) (Brown et al., 2006; Martin et al., 2012; Rosenfeld et al., 2006; Tufail et al., 2010), diabetic macular edema (DME) (Brown et al., 2013; Do et al., 2012; Do et al., 2013; TDRCR, 2015), and macular edema (ME) due to retinal vein occlusion (RVO) (Brown et al., 2010; Brown et al., 2013; Campochiaro et al., 2010; Wu et al., 2008). Ranibizumab (Lucentis®, Genentech, San Francisco, CA) is a humanized, recombinant, monoclonal antibody fragment. Intended for intraocular use, a 0.5mg/0.05ml dose is approved by the Food and Drug Administration for exudative AMD and ME due to RVO; a 0.3mg/0.05ml dose is approved by the FDA for DME, and diabetic retinopathy (DR). Bevacizumab (Avastin®, Genentech, San Francisco, CA) is a humanized monoclonal human immunoglobulin gamma 1 (IgG1) antibody that selectively binds to circulating VEGF and inhibit its binding to cell surface receptors. A 1.25mg/0.05ml is used off-label in the United States and is commonly used worldwide for exudative AMD, DME and RVO. Aflibercept (Eylea®, Regeneron Pharmaceuticals, Tarrytown, NY) is a recombinant protein receptor decoy composed of two VEGF receptors 1 and 2 fused with the Fc region of human IgG1. Compared to the former two anti-VEGF drugs, it has a higher binding affinity for VEGF and it also binds to VEGF-B and Placental growth factor (PGF). A concentration of 2.0mg/0.05ml is approved by the FDA for wet AMD, DME, ME due to RVO, and DR in patients with DME. Ziv-aflibercept (Zaltrap®, Sanofi Aventis, Bridgewater, NJ and Regeneron Pharmaceuticals, Tarrytown, NY), also known as VEGF Trap-oncologic, contains 25 mg/ml ziv-aflibercept, however contains higher sucrose concentrations than aflibercept (Eylea), which results in higher osmolality (Bayer, 2014; Group, 2012). Ziv-aflibercept is approved by the FDA for treatment of resistant or progressing metastatic colorectal cancer. However, Mansour et al. (Mansour et al., 2015; Mansour et al., 2017a; Mansour et al., 2017b); de Oliveira Dias et al. (de Oliveira Dias et al., 2015; de Oliveira Dias et al., 2017; de Oliveira Dias et al., 2016); and Chhablani et al., (Chhablani, 2015; Chhablani et al., 2017), among other authors, have published several reports finding good outcomes and no apparent safety issues in a series of patients treated with intravitreal ziv-aflibercept. Previous studies have shown that anti-VEGF drugs in clinically significant doses do not affect cell viability in vitro in a human retinal pigment epithelium (RPE) cell line (ARPE-19) (Luthra et al., 2006; Malik et al., 2014b). Nonetheless, subtle cytotoxic changes in RPE cells, such as decrease in mitochondrial membrane potential, could be observed even at clinical doses for some anti-VEGF drugs (Malik et al., 2014b). Numerous publications have described in vitro differential responses to the different anti-VEGF drugs in various retinal cells (Deissler et al., 2012; Klettner et al., 2010; Schnichels et al., 2013). Muller cells are predominant glial cells in the retina and provide structural and metabolic support to retinal neurons. Several studies have described numerous functions of Muller cells, including regulation of cellular homeostasis and pH, modulation of neurotransmitter recycling, contribution to the blood-retinal barrier by surrounding retinal capillaries with glial processes (Limb et al., 2002; Reichenbach and Bringmann, 2013), acting as light collectors by directing light to photoreceptors (Franze et al., 2007; Reichenbach and Bringmann, 2013), and secretion and regulation of VEGF and pigment epithelium derived factor (PEDF) (Garcia and Vecino, 2003; Limb et al., 2002; Reichenbach and Bringmann, 2013). Muller cells have also been associated with retinal neuroprotection, wound healing and regeneration (Garcia and Vecino, 2003). The purpose of this study was to evaluate the in vitro response and differences in gene expression of human retinal Muller cells treated with different concentrations of ranibizumab, bevacizumab, aflibercept or ziv-aflibercept. Assays for cell viability, metabolic activity, mitochondrial membrane potential (ΔΨm), reactive oxygen species (ROS) and apoptosis were used to evaluate responses to the anti-VEGF drugs. In addition, differences in the expression levels for angiogenesis-related, pro-apoptotic, inflammation and oxidative stress genes were assessed.

Scalp block for awake craniotomy: Lidocaine-bupivacaine versus lidocaine-bupivacaine with adjuvants

ABSTRACT Methodology: Forty patients were randomly allocated into 4 equal groups based on LA mixture used for scalp block: Group I:received 1.5 mg/kg bupivacaine 0.25% + 5 mg/kg lidocaine 1% with 1:200,000 epinephrine. Group II:same as Group I + 8 mg dexamethasone. Group III:same as Group I + 500 mgMgSO4. Group IV:same as Group I + 8 mgdexamethasone + 500 mgMgSO4. Dexmedetomidine was used for intraoperative sedation and paracetamol for postoperative analgesia. Results: Total intra-operative consumption of dexmedetomidine was highly significantly less in Group II (232 ± 21 µg) and Group III (241 ± 18 µg) compared to Group I (286 ± 27 µg). Group IV (162 ± 25 µg) was highly significantly less than other groups. Time to first paracetamol requirement was highly significantly longer in Group II (245 ± 32 min) and Group III (236 ± 28 min) compared to Group I (187 ± 17 min). Group IV (388 ± 14 min) showed a highly significant longer time than other groups. Group IV consumed highly significant less doses of paracetamol in the first postoperative day (POD1) (2.2 ± 0.1 g) than Group I (2.9 ± 0.4 g), Group II (2.7 ± 0.3 g) and Group III (2.8 ± 0.5 g).Pain in POD1 was significantly higher in Group I at after 3 h of surgery compared to other groups. VAS was comparable during the rest of the times of the study among the four groups. All patients were hemodynamically stable during times of the study. Blood glucose levels were within normal levels with no significant differences between the groups within 6 hof scalp block. Conclusion: Adding either 8 mg©dexamethasone or 500 mg©MgSO4 or both to bupivacaine-lidocaine for scalp block before awake craniotomy improves performance of the block with the best results when combined.

Creation of Superficial Temporal Arteriovenous Loop for Staged Free Tissue Transfer for Dural Coverage in the Setting of Radiation: A Case Report

Free tissue transfer for dural coverage can be challenging for various reasons. In the case of malignancy, patients often have received significant doses of radiation to the head and neck leading to fibrosis and osteoradionecrosis. Not only will free tissue transfer need to accommodate an often large defect but will need to protect intracranial contents. Recipient vessel quality and patency is often affected by comorbidities such as diabetes mellitus and coronary artery disease and can be compounded by radiation. Due to these factors, more proximal vessels in the head and neck are often pursued but due to insufficient length, often require vein grafts or arteriovenous loops to reach the donor vessels for anastomosis. This requires larger incisions and harvesting of lengthy veins. In this study, we discuss a technique of harvesting a small dorsal hand vein, that is hidden well in a hand crease, to create an arteriovenous loop between the superficial temporal vessels. Benefits include exploration of the recipient superficial temporal vessels prior to craniectomy without creating additional incisions, readily accessible recipient vessels to reach donor vessels without harvesting lengthy vein grafts, and allowing for arterialization of the superficial temporal vein leading to decreased venous congestion and thrombosis. While this can be done in 1 stage, we perform this in 2 stages to avoid an increased number of anastomoses and increased risk of flap failure. We present the case of an elderly male with multiple comorbidities and scalp osteoradionecrosis secondary to malignancy who this technique was successfully performed on.

Cracking of composite scintillators after significant doses of irradiation

Cracking of composite scintillators after significant doses of irradiation

182 Bisphenol A, but not bisphenol S, affects key microRNAs during bovine oocyte maturation

Oocyte maturation involves crucial hormone-dependent events that are uniquely susceptible to toxic insults by endocrine disrupting chemicals (EDCs). Emerging evidence suggests that small RNAs, including microRNAs (miRNAs), may be key participants in the response to EDCs. Bisphenol A (BPA) and bisphenol S (BPS) are chemicals with detrimental health effects, with BPA negatively affecting oocyte quality. The mode of action of bisphenols at the epigenetic level is not clear. Several miRNAs have been identified as crucial regulators of gene expression during development. This study aimed to examine key miRNAs in response to BPA or BPS treatment during oocyte maturation. Primary forms (pri-miRNA) and mature forms of miR-21, miR-155, miR-34c, and miR-146a were quantified by quantitative (q)PCR in IVM bovine cumulus-oocyte complexes (COCs) and invitro cultured (IVC) cumulus cells treated with BPA and BPS at physiologically significant doses (0.05mgmL−1). Total RNA, containing both forms of microRNAs, was isolated from pools of 40 COCs on a minimum of three biological replicates. Primary miRNAs and mature miRNAs were reverse transcribed (RT) using qScript cDNA and microRNA/cDNA kits, respectively, and quantified by qPCR, with three technical replicates for each biological one. In addition, mRNA and protein quantification of the downstream target DNMT3A in IVC cumulus cells further enhanced our understanding of EDC interference in epigenetic regulations in female reproduction. Total RNA was isolated from cumulus cells, mRNA (1μg) and mature miRNAs (0.5μg) were RT separately and cDNA was quantified by qPCR, as described above. Expression values were normalized against two housekeeping genes selected by GeNorm analysis. Twenty micrograms of proteins extracted by sonication were loaded on a 8% acrylamide gel and analysed by western blotting. Densitometry analysis was performed on 3 separate blots with protein levels normalized to the loading control, β-actin. One-way ANOVA was used to determine statistical differences among treatment groups with P<0.05 considered statistically significant. Results showed that BPA significantly increased miR-21 in COCs (P=0.02) and cumulus cells (P=0.01), increased pri-miR-21 in oocytes (P=0.03), suppressed miR-34c in cumulus cells (P=0.02), increased miR-155 in denuded oocytes (P=0.04), and had no effect on miR-146a. No changes were observed in response to BPS. Experiments in IVC cumulus cells showed similar miRNA profiles: miR-21 and miR-155 were significantly overexpressed in BPA-treated cells (P=0.04); however, miR-34c and miR-146a were not affected. Messenger RNA levels of DNMT3A increased (P=0.02) and protein levels of DNMT3A decreased in response to BPA (P=0.005). Overall, this study presents novel findings of BPA-induced miRNA dysregulation in IVM bovine oocytes and in IVC bovine cumulus cells. We can speculate that miR-21 participates in the BPA-induced dysregulation of DNMT3A, contributing to decreased fertility. This study did not show any effect of BPS on microRNA expression, suggesting an alternative mechanistic pathway for this analogue.

Evaluation of effective and peak skin dose of patients undergoing interventional cardiology procedures

Introduction: Interventional cardiology procedures result in substantial patient radiation dose due to prolonged fluoroscopy time and radiographic exposure. These procedures not only lead to significant effective doses for the patient but also can potentially cause deterministic effects on the patient’s skin. The aim of this study is to investigate the effective dose and peak skin dose(PSD) of patients during frequently performed cardiology procedures as: coronary angiography(CA) and combined – coronary angiography and percutaneous intervention(CA + PCI) and to evaluate if there is a chance of getting a skin injuries.