Fibroblast growth factor-2 promotes in vitro activation of cat primordial follicles.

This study evaluated the effect of fibroblast growth factor-2 (FGF-2) on the morphology, primordial follicle activation and growth after in vitro culture of domestic cat ovarian tissue. Ovaries (n = 12) from prepubertal domestic cats were collected and fragmented. One fragment was fixed for histological analysis (fresh control). The remaining fragments were incubated in control medium alone or with 10, 50 or 100 ng/ml FGF-2 for 7 days. After in vitro culture, the following endpoints were analyzed: morphology, activation by counting primordial and developing follicles, and growth (follicle and oocyte diameters). Treatment with 100 ng/ml FGF-2 maintained (P > 0.05) the percentage of normal follicles similar to fresh control. Follicle survival was greater (P < 0.05) after culture in 100 ng/ml FGF-2 than in 50 ng/ml FGF-2. The percentage of primordial follicles decreased (P < 0.05) and the percentage of developing follicles increased (P < 0.05) in all treatments compared with fresh tissue. The proportion of developing follicles increased (P < 0.05) in tissues incubated with 100 ng/ml FGF-2 compared with control medium and other FGF-2 concentrations. Furthermore, culture in 10 or 100 ng/ml FGF-2 resulted in increased (P < 0.05) follicle and oocyte diameters compared with fresh tissues and MEM+. In conclusion, FGF-2 at 100 ng/ml maintains follicle survival and promotes the in vitro activation and growth of cat primordial follicles.

First Latin American and Caribbean interlaboratory comparison exercise for SSDLs on reference irradiation capabilities in personal dose equivalent.

A comparison exercise of Latin American and Caribbean Secondary Standards Dosimetry Laboratories (SSDLs) was jointly organized by the International Atomic Energy Agency (IAEA) and the Ionizing Radiation Metrology Laboratory at the Federal University of Pernambuco (LMRI-DEN/UFPE). This exercise was organized during an IAEA regional meeting on the review and update of calibration capabilities in Latin America, held in Recife, during the period from 23 to 27 April 2018 under the technical cooperation project ME-RLA 9085-170572. Fifteen participating SSDLs were required to irradiate optically stimulated personal dosimeters in terms of the personal dose equivalent Hp(10) in137Cs radiation quality. In addition, the IAEA Dosimetry Laboratory in Seibersdorf, Austria, and the National Physical Laboratory in Teddington, Middlesex, UK participated in this exercise as reference institutes. Each participant received 10 dosimeters that were hand-carried directly to the SSDL. Two nominal dose values of 2 mSv and 4 mSv were selected for this exercise. The participants irradiated the dosimeters using the setup and the procedures which are normally used in their standard laboratory for Hp(10) dosimeter irradiations. The dosimeters were evaluated as they were received by the coordinating laboratory, using a single BeOSL Reader. The results show that, except for one laboratory, the differences between the dosimeter reading and the assigned values were within 10%; this is consistent with the expanded uncertainty. The results indicate that most of the participant laboratories have a good capability to irradiate personal dosimeters in the quantity Hp(10).

Scan factors and practices associated with radiation doses for chest CT: current Brazilian scenario.

The main purpose of this study was to compare the parameters of computed tomography (CT) and the corresponding patient doses undergoing chest CT scan examinations in different regions of Brazil, providing the current scenario of how these procedures are being carried out in the country as well as the patient dose distribution. Thirty institutions, across 17 states and the Federal District, participated in the survey. The evaluation included 30 multislice CTs of seven different models, manufactured by General Electric (GE) Healthcare. For each institution, data from 10 adult chest CT examinations, performed without contrast, were collected remotely. The analysis of the results showed a significant difference of the CTDIvolvalues, ranging from 1.1 mGy to 46.6 mGy in seven institutions. The mean value of CTDIvolwas higher than values found in the literature and the UK Reference Levels. It was also observed that, regardless of the region of the country, for the same CT model, different scanning parameters were used, which resulted in CTDIvolup to 5 times higher in some institutions. Repetitions of CT acquisitions and scouts with radiation field dimensions larger than the region of interest were found in 25% of chest examinations, resulting in higher absorbed doses. The results of this work show a mapping of the chest CT procedures, which enables the establishment of strategic plans for the country. In addition, each institution will be able to implement an appropriate optimization program and establish institutional reference levels.

Evaluation of a 3D printed OSL eye lens dosimeter for photon dosimetry.

This work demonstrates the use of high-resolution 3D printing to fine-tune the low energy dependence of an eye lens dosimeter holder associated to a BeO OSL detector element (ezClip). Five geometries of the denominated iBe dosimeter were developed, three with a variation in the thickness of the wall in front of the sensitive element that tailor the response at low radiation energies; and three with variations of width and curvature in order to vary the angular response of the dosimeter badges. Additive manufacturing was accomplished using stereolithography which gave a high degree of accuracy and precision. The optimised dosimeter badges showed a low energy and angular dependence, within -20% to +20% in the energy range of 24 keV to 662 keV and from 0 to 60° incidence; and within -10% to +10% in the energy range of 24 keV to 164 keV and from 0 to 60° incidence. In contrast to other dosimeters with higher effective atomic numbers, the use of BeO as the sensitive element resulted in a flat energy and angular dependence response at low energies. A significant reduction in the measurement uncertainty in the diagnostic radiology energy range was achieved.

Resveratrol has dose-dependent effects on DNA fragmentation and mitochondrial activity of ovine secondary follicles cultured in vitro.

The worldwide consumption of red wine, nuts and grapes has resulted in increased human exposure to resveratrol, which could affect reproductive function. However, the effect of resveratrol on in vitro culture of early-stage ovarian follicles has never been investigated. The aims of the present study were to evaluate the effect of resveratrol on sheep secondary follicle morphology, growth, DNA fragmentation, intracellular levels of glutathione (GSH) and active mitochondria. Secondary follicles were isolated from the ovaries and cultured for 18 days in supplemented α-MEM+ (control medium) or in control medium containing resveratrol (2, 10 or 30 µM). The parameters analyzed were morphology, antrum formation, follicle diameter, DNA fragmentation, GSH levels and mitochondrial activity. After 18 days, all resveratrol groups significantly decreased the percentages of morphologically normal follicles compared with the control group (α-MEM+). Antrum formation was higher in both α-MEM+ and 2 µM resveratrol groups than in the 10 µM resveratrol group. In addition, 30 µM resveratrol increased the percentage of oocytes with DNA damage compared with the control. Oocytes from follicles treated with 10 or 30 µM resveratrol significantly decreased intracellular GSH levels compared with the 2 µM resveratrol group. Moreover, follicles in α-MEM+ (control) showed more active mitochondria than those in 10 or 30 µM resveratrol. In conclusion, ovine isolated secondary follicles are able to grow to the antral stage after in vitro culture in medium containing 2 µM resveratrol, maintaining the same rates of DNA damage, GSH levels and mitochondrial function as the control medium. However, the addition of 30 µM resveratrol increased DNA fragmentation and oxidative stress through decreasing mitochondrial activity.

Amburana cearensis leaf extract maintains survival and promotes in vitro development of ovine secondary follicles.

The antioxidant properties of Amburana cearensis extract may be a useful substitute for standard cell culture medium. Thus, the aim of this study was to evaluate the effect of this extract, with or without supplementation, on in vitro survival and development of sheep isolated secondary follicles. After collection of the ovaries, secondary follicles were isolated and cultured for 18 days in α-MEM+ supplemented with bovine serum albumin, insulin, transferrin, selenium, glutamine, hypoxanthine and ascorbic acid (control medium) or into medium composed of different concentrations of A. cearensis extract without supplements (Amb 0.1; 0.2 or 0.4 mg/ml) or A. cearensis extract supplemented with the same substances described above for α-MEM+ supplementation. The A. cearensis supplemented medium was named Amb 0.1+; 0.2+ or 0.4+ mg/ml. There were more morphologically normal follicles in Amb 0.1 or Amb 0.4 mg/ml than in the control medium (α-MEM+) after 18 days of culture. Moreover, the percentage of antrum formation was significantly higher in Amb 0.1 or Amb 0.2 mg/ml than in α-MEM+ and Amb 0.1+ mg/ml, and similar to the other treatments. All A. cearensis extract media induced a progressive and significant increase in follicular diameter throughout the culture period. In conclusion, this study showed that 0.1 mg/ml of this extract, without supplementation, maintains follicular survival and promotes the development of ovine isolated secondary follicles in vitro. This extract can be an alternative culture medium for preantral follicle development.

Lower apoptosis rate in ovine preantral follicles from ovaries stored in supplemented preservation media.

The aim of this study was to investigate the effect of ovarian tissue transportation conditions (medium and period of time) on the morphology, apoptosis and development of ovine preantral follicles cultured in vitro. Each ovarian pair was cut into nine slices, with one fragment being fixed immediately (fresh control). The remaining fragments were placed individually in cryotubes containing conservation medium (minimal essential medium (MEM) without supplementation or MEM+ - with supplementation) and stored at 35ºC for 6 or 12 h without (non-cultured) or with subsequent culture for 5 days. Then, the fragments were processed for histological and terminal deoxynucleotidyl transferase (TdT) mediated dUTP nick-end labelling (TUNEL) examination. Preservation of ovarian slices in MEM or MEM+ (non-cultured) resulted in similar percentages of normal follicles when compared with the fresh control. Nevertheless, compared with the fresh control, a decrease in the percentage of normal follicles was observed in tissues cultured for 5 days. Only for tissues preserved in supplemented medium (MEM+) for 6 h, the percentage of TUNEL positive cells was similar between non-cultured tissues and tissues cultured for 5 days. Follicular activation and growth (follicular and oocyte diameter) were higher in cultured tissues than in fresh control or non-cultured tissues, except those from fragments preserved for 6 h in MEM and then cultured for 5 days in which no growth was observed. In conclusion, ovine ovarian tissue was successfully preserved in supplemented medium (MEM+) at a temperature close to physiological values (35°C) for up to 6 h without affecting apoptosis in the ovarian follicles and their ability to develop in vitro.

Estimation of organ doses to patients undergoing hepatic chemoembolization procedures.

The aim of this study is to evaluate organ and tissue absorbed doses to patients undergoing hepatic chemoembolization procedures performed in two hospitals in the city of Recife, Brazil. Forty eight patients undergoing fifty hepatic chemoembolization procedures were investigated. For the 20 cases with PA projection only, organs and tissues dose to KAP conversion coefficients were calculated using the mesh-based anthropometric phantom series FASH and MASH coupled to the EGSnrc Monte Carlo code. Clinical, dosimetric and irradiations parameters were registered for all patients. The maximum organ absorbed doses found were 2.4 Gy, 0.85 Gy, 0.76 Gy and 0.44 Gy for skin, kidneys, adrenals and liver, respectively.

Immunohistochemical localization of fibroblast growth factor-2 in the sheep ovary and its effects on pre-antral follicle apoptosis and development in vitro.

Studies with sheep are important to improve our knowledge about the factors that control folliculogenesis in mammals and to explore possible physiological differences among species. The aims of this study were to characterize FGF-2 protein expression in ovine ovaries and to verify the effect of FGF-2 on the morphology, apoptosis and growth of ovine pre-antral follicles cultured in vitro. After collection, one fragment of ovarian tissue was fixed for histological analysis and TUNEL analysis (fresh control). The remaining fragments were cultured for 7 days in control medium (α-MEM(+) ) alone or supplemented with FGF-2 at different concentrations (1, 10, 50, 100 or 200 ng/ml). After culturing, ovarian tissue was destined to histology and TUNEL analysis, and oocyte and follicle diameters were measured. The immunostaining for FGF-2 was observed in oocytes from primordial, primary and secondary follicles, as well as in granulosa cells of secondary and antral follicles. The percentage of normal follicles was similar among control medium, 1 and 10 ng/ml FGF-2, and significantly higher than those observed in 50, 100 or 200 ng/ml FGF-2. A significant increase in follicle diameter was observed when tissues were cultured in 10, 50, 100 or 200 ng/ml FGF-2 compared with the fresh control and the other treatments. Similar results were observed for oocyte diameter in tissues cultured with 50, 100 or 200 ng/ml FGF-2 (p < 0.05). However, the percentage of apoptotic cells only decreased (p < 0.05) in ovarian tissues cultured in 1 or 10 ng/ml FGF-2 compared with the control medium and other FGF-2 treatments. In conclusion, this study demonstrated the presence of FGF-2 in ovine ovaries. Furthermore, 10 ng/ml FGF-2 inhibits apoptosis and promotes ovine follicle growth. As the sheep ovary is more similar to that of humans, the culture system demonstrated in this work seems to be an appropriate tool for studies towards human folliculogenesis.

Protein localization of epidermal growth factor in sheep ovaries and improvement of follicle survival and antrum formation in vitro.

The aims of this study were to characterize EGF protein expression in ovine ovaries and to verify the effect of EGF on the in vitro development of isolated pre-antral follicles. After collection, ovarian tissue was fixed for immunohistochemical analysis. Additional pairs of ovaries were collected, and secondary follicles were cultured for 18 days in α-MEM(+) (control) alone or supplemented with EGF (1, 10 or 50 ng/ml). The immunostaining for EGF was observed in oocytes from pre-antral and antral follicles, in granulosa cells of primary and secondary follicles, as well as in cumulus and mural cells of antral follicles. After 18 days, the results showed that treatment with 50 ng/ml EGF significantly increased the percentage of morphologically normal follicles compared with the control group (α-MEM(+) ) and significantly reduced the precocious extrusion of oocytes and increased the percentage of antral follicles compared with the control and 1 ng/ml EGF. All the treatments induced a progressive and significant increase of the follicular diameter throughout the period of culture. However, there were no significant differences in follicular diameter or in the daily growth rate among treatments. In conclusion, this study demonstrated the presence of EGF in ovine ovaries. Moreover, 50 ng/ml EGF increased the percentage of normal follicles and improved antrum formation in isolated ovine follicles after 18 days of in vitro culture.

Cerclage sling technique using temporalis muscle fascia to manage paralytic lagophthalmos: A preliminary study.

PURPOSE: Despite various existing surgical techniques, treatment of facial nerve palsy remains difficult. The purpose of this report is to present the cerclage sling technique using temporalis fascia to manage paralytic lagophthalmos. METHODS: A series of six patients underwent a cerclage sling technique using temporalis muscle fascia to treat paralytic lagophthalmos. The technique is presented in detail. Symptoms, palpebral fissures, and lagophthalmos were assessed pre- and postoperatively. Data were submitted for statistical analysis. RESULTS: After surgery, all patients achieved a reduction in clinical symptoms. The upper eyelids had lowered, and the inferior eyelids had elevated, reducing ocular exposure even if mild residual lagophthalmos was present. CONCLUSION: Cerclage using the temporalis muscle fascia sling technique is a safe and effective procedure to treat facial nerve paralytic lagophthalmos. A reduction in ocular exposure and lagophthalmos provides improvement in clinical symptoms and eyelid function.

Immunolocalization of melatonin and follicle-stimulating hormone receptors in caprine ovaries and their effects during in vitro development of isolated pre-antral follicles.

The expression of melatonin type 1 (MT1) and FSH (FSHR) receptors in caprine ovaries and the effects of these hormones on the in vitro development of isolated pre-antral follicles were evaluated. Follicles (≤200 µm) were cultured for 12 days in α-MEM (control) or melatonin (100 or 1000 pg/ml) or sequential melatonin medium (100 pg/ml: from day 0 to day 6; 1000 pg/ml: from day 6 to day 12; experiment 1) and in control or sequential FSH (100 ng/ml from day 0 to day 6; 500 ng/ml from day 6 to day 12) or sequential melatonin or this latter plus sequential FSH (experiment 2). MT1 and FSHR expressions were observed in granulosa cells from secondary and antral follicles. The oocytes from primordial and primary follicles also express FSHR. Sequential melatonin increased the percentage of normal follicles and oocyte recovery compared with the control or melatonin (1000 pg/ml) at day 12. In experiment 2, all the treatments increased the normal follicles and growth compared with the control. In conclusion, this study demonstrated the presence of MT1 and FSHR in caprine ovaries. The addition of increased concentrations of melatonin (sequential medium) or FSH can be used to promote the in vitro development of caprine pre-antral follicles.

Organ doses and risks of computed tomography examinations in Recife, Brazil.

Computed tomography (CT) examinations have increased significantly in recent years due to technological innovations. In some industrialised countries, CT contributes to the population dose as much as background radiation. In developing countries, the uses and risks of CT have not been well characterised. The purpose of this investigation was to assess potential stochastic and deterministic radiation effects from common CT exams performed in six hospitals of Recife, Pernambuco. Scanning parameters and patient gender and age were collected for a total of 285 patients undergoing CT examinations of the head (90), chest (75), abdomen (60) and abdomen-pelvis (60). The organ doses, which were calculated using the ImPACT dosimetry calculator, varied significantly among institutions. Organs such as the brain, the heart and the eye lenses, which exhibited doses as high as 85, 42 and 100 mGy, respectively, are of concern for the production of cerebrovascular and cardiovascular diseases and cataracts. Effective cancer risks were calculated using Brenner methodology and BEIR-VII risk factors. They range from 1.8 to 110.2 cases per 100000 persons for cancer induction and from 1.5 to 63.0 cases per 100000 for cancer mortality. To reduce doses, a quality assurance programme that includes procedural justification and radiation protection optimisation should be implemented.

Involvement of Phosphorylated Akt and FOXO3a in the Effects of Growth and Differentiation Factor-9 (GDF-9) on Inhibition of Follicular Apoptosis and Induction of Granulosa Cell Proliferation After In Vitro Culture of Sheep Ovarian Tissue.

This study aimed to evaluate the effects of growth and differentiation factor-9 (GDF-9) on the morphology, activation, apoptosis, and granulosa cell proliferation of ovine preantral follicles cultured within ovarian tissue slices and to verify whether GDF-9 could influence follicular activation through the phosphatidylinositol 3-kinase/protein kinase B/forkhead box O3a (PI3K/Akt/FOXO3a) pathway. Ovine ovarian fragments were cultured in α-MEM+ or α-MEM+ with GDF-9 (1, 50, 100, 200, or 400 ng/ml) for 7 days. Apoptosis and cell proliferation were analyzed. Next, the activation of the PI3K was inhibited with LY294002, and immunostaining for p-Akt and p-FOXO3a proteins was assessed. The concentration of 50 ng/ml GDF-9 had (P < 0.05) more morphologically normal follicles compared to all treatments, except 1 ng/ml GDF-9. Moreover, 50 ng/ml GDF-9 increased primordial follicle activation compared to all treatments, except α-MEM+ and 1 ng/ml GDF-9. However, the concentration of 50 ng/ml GDF-9 showed higher cell proliferation and lower apoptosis than α-MEM+ and 1 ng/ml GDF-9 treatments. Culture of the ovarian tissue with LY294002 inhibited the activation of primordial follicles and reduced p-Akt immunostaining in both α-MEM+ and 50 ng/ml GDF-9 treatments. In addition, after culture with LY294002, the percentage of oocytes with nuclear p-FOXO3 was higher in 50 ng/ml GDF-9 than in the control medium (α-MEM+). In conclusion, after culture of ovine ovarian cortical slices, the addition of 50 ng/ml GDF-9 reduces follicular apoptosis and promotes granulosa cell proliferation likely through the involvement of phosphorylated Akt and FOXO3a.

Antinociceptive and anti-inflammatory activities of Hymenaea martiana Hayne (Fabaceae) in mice.

Hymenaea martiana is a species popularly known in Northeastern Brazil as "jatobá" and used in folk medicine to treat pain and inflammation. The aim of this work was to evaluate the antinociceptive and anti-inflammatory activity of H. martiana. In the present study, we carried out an investigation about the effects of the crude ethanolic extract (Hm-EtOH) and the ethyl acetate fraction (Hm-AcOEt) in models of nociception and inflammation in mice. Chemical (acetic acid-induced writhing and formalin) and thermal stimuli (hot plate) were used for the evaluation of antinociceptive activity, while for the anti-inflammatory profile paw edema induced by carrageenan was used, along with leukocyte migration to the peritoneal cavity. The presence of the flavonoid astilbin in the samples was characterized through HPLC-DAD-MS analysis. Hm-EtOH and Hm-AcOEt (100, 200 and 400 mg.kg-1, i.p.) significantly reduced the number of abdominal contortions and decreased the paw licking time in the formalin test. In the hot plate, the extract increased the latency time of animals. Hm-EtOH and Hm-AcOEt inhibited significantly the increase in the edema after the administration of carrageenan. Hm-EtOH and Hm-AcOEt inhibited leukocyte migration in the peritonitis test. HPLC-DAD-MS analysis of Hm-EtOH and Hm-AcOEt revealed the presence of the flavonoid astilbin in the samples. According to the results of this study, both Hm-EtOH and Hm-AcOEt have antinociceptive and anti-inflammatory activities, which could be related with the presence of flavonoid in the extracts. The results reinforce the popular use of this plant.

Melatonin improves development, mitochondrial function and promotes the meiotic resumption of sheep oocytes from in vitro grown secondary follicles.

The aim of this study was to evaluate follicular survival and development of ovine isolated secondary follicles cultured in medium containing fixed or sequential concentrations of melatonin and further oocyte maturation. Isolated secondary follicles were cultured for 18 days in α-MEM+ alone (control) or with different concentrations of melatonin (100, 500 or 1000 pg/mL) or sequential concentrations of melatonin (Mel Seq: Day 6 = 100; Day 12 = 500; Day 18 = 1000 pg/mL). The percentages of morphologically normal follicles and antral cavity formation increased significantly in 1000 pg/mL melatonin compared to the other treatments. After 18 days, 1000 pg/mL melatonin (Mel 100) showed a greater (P < 0.05) follicular diameter than α-MEM+, 100 and 500 pg/mL melatonin. In addition, the concentration of 500 pg/mL melatonin showed a higher (P < 0.05) percentage of fully grown oocytes than α-MEM+, Mel 100 and Mel Seq treatments. After oocyte maturation, the levels of ROS were lower (P < 0.05) in 1000 pg/mL melatonin (Mel 1000) than in other treatments. Both Mel 1000 and Mel Seq treatments showed significantly higher levels of mitochondrial activity than other treatments. There were no significant differences between 500 and 1000 pg/mL melatonin regarding meiotic stages. In conclusion, the concentration of 1000 pg/mL melatonin maintains survival, promotes follicular development and increases the levels of active mitochondria after in vitro culture of sheep secondary follicles. Moreover, this concentration promotes the meiotic competence of oocytes and decreases the production of ROS during oocyte maturation.

Effects of melatonin on the in vitro growth of early antral follicles and maturation of ovine oocytes.

This study aimed to evaluate the effect of melatonin on the in vitro culture and maturation of isolated sheep early antral follicles. Isolated early antral follicles were cultured for 12 d in α-minimum essential medium (MEM+) alone (control) or α-MEM+ added with fixed different concentrations (100, 500, or 1,000 pg/mL) or a sequential concentration of melatonin (MelSeq; day 6 = 100; day 12 = 500 pg/mL). The percentage of morphologically normal follicles was higher (P < 0.05) in 500 pg/mL melatonin than the other treatments at 6 d. Mel 500 also showed a higher rate of fully grown oocytes (P < 0.05) than other treatments. After in vitro culture, reactive oxygen species (ROS) levels in oocytes were similar between Mel 500 and MelSeq, with both being lower (P < 0.05) than other treatments. Oocytes cultured in both Mel 500 and Mel 1000 showed glutathione peroxidase levels similar (P > 0.05) to the control group and higher (P < 0.05) than other treatments. Mitochondrial activity was similar (P > 0.05) among control, Mel 500, and Mel 1000 treatments. Mel 500 treatment presented a higher percentage of germinal vesicle breakdown oocytes than the control group and similar percentages to the other treatments. Follicles cultured in melatonin followed by oocyte maturation with the addition of 500 pg/mL melatonin in maturation medium showed increased (P < 0.05) levels of mitochondrial activity compared to α-MEM+ alone. In conclusion, the concentration of 500 pg/mL of melatonin promotes development and decreases ROS levels of ovine oocytes from in vitro grown early antral follicles. Moreover, melatonin increases mitochondrial activity and promotes the acquisition of meiotic competence of these oocytes.

Susceptibility to chemical insecticides of two Brazilian populations of the visceral leishmaniasis vector Lutzomyia longipalpis (Diptera: Psychodidae).

OBJECTIVES: To investigate the insecticide susceptibility of two geographically separated Lutzomyia longipalpis populations (Lapinha and Montes Claros) with different histories of insecticide exposure (i.e. no exposure and repeated exposure, respectively). METHODS: (i) Bioassay monitoring of sand fly survival over time when exposed to a range of insecticides; and (ii) analysis of the level of insecticide detoxification enzymes in individual sand flies caught at both study sites. Insecticides tested were the organophosphates malathion and fenitrothion and the pyrethroids lambda-cyhalothrin, permethrin and deltamethrin. RESULTS: Survival analyses showed that whilst there was no overall significant difference in susceptibility of both populations to organophosphates, Lapinha sand flies were significantly more susceptible to pyrethroids than those from Montes Claros. Multiple regression analyses also showed that insecticide susceptibility in both locations varied with sand fly sex. The relative susceptibilities of the two sand fly populations to tested insecticides were also compared. Thus, Montes Claros sand flies were most susceptible to malathion, followed by fenitrothion, deltamethrin and permethrin. Those from Lapinha were most susceptible to lambda-cyhalothrin, followed by malathion, permethrin, deltamethrin and fenitrothion. Biochemical analyses demonstrated that Montes Claros sand flies had significantly lower insecticide detoxification enzyme activity than Lapinha sand flies. CONCLUSIONS: Our results are the first record of significantly reduced susceptibility to the insecticides used in control of wild populations of Lu. longipalpis. They demonstrate the importance of evaluating chemicals against this species by conventional bioassay and microplate assays before and during spraying programmes.

Evaluation of the MOSkin dosimeter for diagnostic X-ray CT beams.

The aim of the present study was to evaluate the response of the MOSkin MOSFET dosimeter for X-ray diagnostic CT beams. Experiments were performed to investigate the sensitivity, energy dependence, reproducibility, fading and angular dependence of the dose response for the device. The dosimeter's performance was evaluated for the standard radiation qualities RQT 8, RQT 9 and RQT 10 in a metrology laboratory. In a CT scanner, the MOSkin was used to assess the air kerma profile and the dose profile in a phantom. The integral of the dose profile was compared to the CPMMA,100 measured with a pencil ionization chamber. The results showed that the MOSkin response was linear and reproducible with doses in the CT range. Energy dependence varied up to a factor of 1.19 among the tested X-ray energies. Angular dependence of the response was not greater than 7.8% within the angle range from 0 to 90 degrees. Signal fading within 3 min was negligible. Additionally, the MOSkin was able to accurately assess the air kerma profile and the integral of the dose profile in a CT scanner. The integral of the dose profile in a phantom was in agreement with the CPMMA,100. The presented results demonstrated the potential of the MOSkin for application in CT dosimetry.

REDUCTION OF STAFF RADIATION DOSE IN PROSTATIC ARTERY EMBOLISATION.

Prostatic artery embolisation (PAE) is used to treat patients with benign prostatic hyperplasia and with lower urinary obstructive tract symptoms. It is an interventional procedure which uses fluoroscopy equipment and can result in exposure to high doses of radiation in patients and staff. We aimed to demonstrate the reduction of radiation doses received by staff during PAE by implementing an optimised protocol called Radiation Exposure Curtailment for Embolisation (RECiFE). This protocol was implemented in cooperation with the medical team and technical team using Siemens Combined Applications to Reduce Exposure (CARE) protocol. The results showed approximately 83% reduction in the radiation doses received by the main physician during PAE. Thus, by adjusting the acquisition parameters of the angiographic equipment and implementing the RECiFE protocol, it is possible to optimise the PAE procedure and reduce the staff radiation dose.