Reconstructive dosimetry for cutaneous radiation syndrome

According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.

Polycystic echinococcosis in the state of Acre, Brazil: contribution to patient diagnosis, treatment and prognosis

The lack of knowledge regarding polycystic hydatid disease results in delayed or even incorrect diagnosis. The lack of systematic information regarding treatment also makes it difficult to assess the results and prognosis in patients with peritoneal and hepatic lesions caused by Echinococcus vogeli. Here we describe the clinical features of patients, propose a radiological classification protocol and describe a therapeutic option for the treatment of hydatid disease that previously had only been used for cases of cystic echinococcosis (Echinococcus granulosus). A prospective cohort study was initiated in 1999 and by 2009 the study included 60 patients. These patients were classified according to the PNM classification (parasite lesion, neighbouring organ invasion and metastases) and placed in one of three therapeutic modalities: (i) chemotherapy with albendazole at a dose of 10 mg/kg/day, (ii) surgical removal of cysts or (iii) percutaneous puncture of the cysts via puncture, aspiration, injection and re-aspiration (PAIR). The results were stratified according to therapeutic outcome: "cure", "clinical improvement", "no improvement", "death" or "no information". The PNM classification was useful in indicating the appropriate therapy in cases of polycystic hydatid disease. In conclusion, surgical therapy produced the best clinical results of all the therapies studied based on "cure" and "clinical improvement" outcomes. The use of PAIR for treatment requires additional study.

Readjustment of abdominal computed tomography protocols in a university hospital: impact on radiation dose

AbstractObjective:To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters.Materials and Methods:Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A – 551 studies) and three months after (group B – 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDIvol per phase, mean DLP per phase, and mean DLP per scan.Results:A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDIvol per phase, DLP per phase and DLP per scan (p < 0.001).Conclusion:The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans.

Estimation of Fetal Weight during Labor: Still a Challenge

Objective To evaluate the accuracy of fetal weight prediction by ultrasonography labor employing a formula including the linear measurements of femur length (FL) and mid-thigh soft-tissue thickness (STT). Methods We conducted a prospective study involving singleton uncomplicated term pregnancies within 48 hours of delivery. Only pregnancies with a cephalic fetus admitted in the labor ward for elective cesarean section, induction of labor or spontaneous labor were included. We excluded all non-Caucasian women, the ones previously diagnosed with gestational diabetes and the ones with evidence of ruptured membranes. Fetal weight estimates were calculated using a previously proposed formula [estimated fetal weight = [1] 1687.47 + (54.1 x FL) + (76.68 x STT). The relationship between actual birth weight and estimated fetal weight was analyzed using Pearson's correlation. The formula's performance was assessed by calculating the signed and absolute errors. Mean weight difference and signed percentage error were calculated for birth weight divided into three subgroups: < 3000 g; 3000-4000g; and > 4000 g. Results We included for analysis 145 cases and found a significant, yet low, linear relationship between birth weight and estimated fetal weight (p < 0.001; R2 = 0.197) with an absolute mean error of 10.6%. The lowest mean percentage error (0.3%) corresponded to the subgroup with birth weight between 3000 g and 4000 g. Conclusions This study demonstrates a poor correlation between actual birth weight and the estimated fetal weight using a formula based on femur length and mid-thigh soft-tissue thickness, both linear parameters. Although avoidance of circumferential ultrasound measurements might prove to be beneficial, it is still yet to be found a fetal estimation formula that can be both accurate and simple to perform.

Estimation of weed dry biomass and grain yield as a function of growth and yield traits under allelopathic weed management in maize

Growing concerns about toxicity and development of resistance against synthetic herbicides have demanded looking for alternative weed management approaches. Allelopathy has gained sufficient support and potential for sustainable weed management. Aqueous extracts of six plant species (sunflower, rice, mulberry, maize, brassica and sorghum) in different combinations alone or in mixture with 75% reduced dose of herbicides were evaluated for two consecutive years under field conditions. A weedy check and S-metolachlor with atrazine (pre emergence) and atrazine alone (post emergence) at recommended rates was included for comparison. Weed dynamics, maize growth indices and yield estimation were done by following standard procedures. All aqueous plant extract combinations suppressed weed growth and biomass. Moreover, the suppressive effect was more pronounced when aqueous plant extracts were supplemented with reduced doses of herbicides. Brassica-sunflower-sorghum combination suppressed weeds by 74-80, 78-70, 65-68% during both years of study that was similar with S-metolachlor along half dose of atrazine and full dose of atrazine alone. Crop growth rate and dry matter accumulation attained peak values of 32.68 and 1,502 g m-2 d-1 for brassica-sunflower-sorghum combination at 60 and 75 days after sowing. Curve fitting regression for growth and yield traits predicted strong positive correlation to grain yield and negative correlation to weed dry biomass under allelopathic weed management in maize crop.

Paraquat poisoning: an experimental model of dose-dependent acute lung injury due to surfactant dysfunction

Since the most characteristic feature of paraquat poisoning is lung damage, a prospective controlled study was performed on excised rat lungs in order to estimate the intensity of lesion after different doses. Twenty-five male, 2-3-month-old non-SPF Wistar rats, divided into 5 groups, received paraquat dichloride in a single intraperitoneal injection (0, 1, 5, 25, or 50 mg/kg body weight) 24 h before the experiment. Static pressure-volume (PV) curves were performed in air- and saline-filled lungs; an estimator of surface tension and tissue works was computed by integrating the area of both curves and reported as work/ml of volume displacement. Paraquat induced a dose-dependent increase of inspiratory surface tension work that reached a significant two-fold order of magnitude for 25 and 50 mg/kg body weight (P<0.05, ANOVA), sparing lung tissue. This kind of lesion was probably due to functional abnormalities of the surfactant system, as was shown by the increase in the hysteresis of the paraquat groups at the highest doses. Hence, paraquat poisoning provides a suitable model of acute lung injury with alveolar instability that can be easily used in experimental protocols of mechanical ventilation

Pharmacokinetic and parasitological evaluation of the bone marrow of dogs with visceral leishmaniasis submitted to multiple dose treatment with liposome-encapsulated meglumine antimoniate

The aim of the present study was to evaluate the impact of a multiple dose regimen of a liposomal formulation of meglumine antimoniate (LMA) on the pharmacokinetics of antimony in the bone marrow of dogs with visceral leishmaniasis and on the ability of LMA to eliminate parasites from this tissue. Dogs naturally infected with Leishmania chagasi received 4 intravenous doses of either LMA (6.5 mg antimony/kg body weight, N = 9), or empty liposomes (at the same lipid dose as LMA, N = 9) at 4-day intervals. A third group of animals was untreated (N = 8). Before each administration and at different times after treatment, bone marrow was obtained and analyzed for antimony level (LMA group) by electrothermal atomic absorption spectrometry, and for the presence of Leishmania parasites (all groups). There was a significant increase of antimony concentration from 0.76 µg/kg wet organ (4 days after the first dose) to 2.07 µg/kg (4 days after the fourth dose) and a half-life of 4 days for antimony elimination from the bone marrow. Treatment with LMA significantly reduced the number of dogs positive for parasites (with at least one amastigote per 1000 host cells) compared to controls (positive dogs 30 days after treatment: 0 of 9 in the LMA group, 3 of 9 in the group treated with empty liposomes and 3 of 8 in the untreated group). However, complete elimination of parasites was not achieved. In conclusion, the present study showed that multiple dose treatment with LMA was effective in improving antimony levels in the bone marrow of dogs with visceral leishmaniasis and in reducing the number of positive animals, even though it was not sufficient to achieve complete elimination of parasites.

Dose inseminante utilizada na fertilização artificial de ovócito de piracanjuba (Brycon orbignyanus)

A piracanjuba (Brycon orbignyanus Valenciennes, 1849) é uma espécie de peixe migratória, ameaçada de extinção. O objetivo do presente estudo foi determinar a dose inseminante na fertilização artificial de ovócitos de piracanjuba. Para isso, utilizou-se delineamento em blocos casualizados, com quatro tratamentos e três repetições. Três casais de piracanjuba, selecionados dos tanques de reprodutores da Estação Ambiental de Itutinga (EAI - CEMIG), no período de piracema 2006/2007, receberam aplicação de hormônio extrato bruto de hipófise de carpa (EBHC) para obtenção dos gametas. Adotaram-se quatro tratamentos diferentes para a fertilização de 0,1 grama de ovócitos: 10µL, 20µL, 30µL e 40µL de sêmen. As amostras foram ativadas com 5 mL de água do próprio tanque e, em seguida, levadas para incubadoras, dotadas de renovação constante de água, à temperatura de 28ºC. Após 8 e 16 horas, analisaram-se as taxas de fertilização (ovos viáveis) e de eclosão dos ovos, respectivamente. Os resultados obtidos foram comparados pelo teste de Tukey a 5%. As relações sêmen-ovócitos testadas não alteraram as taxas de fertilização e eclosão (P>0,05). O número de espermatozoides-ovócitos, variando de 10,4 x10(5) a 41,6 x10(5), foi eficiente para obtenção de boas taxas de fertilidade.

Prevalence of periodontal disease in dogs and owners' level of awareness - a prospective clinical trial

Periodontal disease (PD) is widely known among veterinarians for its high prevalence and serious consequences to the dogs. The objective of this study was to assess the occurrence of PD in dogs that live in the micro-region of Viçosa, treated at the Veterinary Hospital of the Federal University of Viçosa (HVT - Hospital Veterinário da Universidade Federal de Viçosa), as well as to assess how aware of this disease dog owners are. In order to do so, all dogs treated at the HVT from March 10th, 2009 to November 30th, 2009, on alternate days, had their oral cavities examined. Medical history data, such as age, type of food, main complaint and owner consent, halitosis, presence of dental calculus, inflammation and gingival recession and tooth loss, were collected. A prevalence of 88.67% was found for PD in dogs referred to the HVT, and 2.67% were referred due to this disease. Of all the owners who participated in the study, 43.83% knew about periodontal disease and of these 17.46% made use of some type of prevention or treatment. Therefore, periodontal disease is highly prevalent and the owners are not aware of the disease. Thus, a dog owner clarification program on periodontal disease is needed in the area where HVT-UFV operates.

Ampicilina K em dose única, por via oral, no tratamento da gonorréia

Foram tratados 70 pacientes do sexo masculino portadores de uretrite gonocócica aguda com 3,0 g de Ampicilina K por via oral, em dose única. Em 87,1% dos casos houve desaparecimento da secreção uretral; na grande maioria dos casos entre 24 e 72 horas. Considerados mais 3 casos em que houve persistência da secreção pós tratamento, mas com ausência de gonococos aos exames bacteriológicos (cura bacteriológica) o sucesso terapêutico pode ser elevado para 91,4%.

Hetacilina em dose única no tratamento da gonorréia

Foram tratados 155 pacientes do sexo masculino, portadores de uretrite gonocócica aguda, com 3,0 g de Hetacilina K por via oral (70 casos) ou 1,0 g do mesmo medicamento por via intramuscular (85 casos). Em 88,6% dos casos tratados pela via oral, e em 93% dos casos tratados com uma injeção intramuscular, o corrimento desapareceu em um tempo médio de 48 horas. Não foram observadas reações de intolerância ao medicamento.

Cicatrização de lesões cutâneas de leishmaniose americana com dose única de pamoato de cicloguanil

Relata-se a completa cicatrização de lesões de leishmaniose tegumentar americana, com Pamoato de Cicloguanil (Comolar Parke-Davis) em 33 pacientes, dos quais 28 receberam dose única e 5 dose dupla desse quimioterápico. O diagnóstico foi comprovado pela presença de leishmanias ao exame direto de laboratório. A idade das lesões variou de 8 dias até 12 meses, com 82% dos casos entre 8 e 30 dias. O tempo médio de cicatrização foi de 104 dias variando entre 60 e 170 dias, para os doentes que receberam apenas uma dose do medicamento. Os doentes que receberam duas doses tiveram a completa cicatrização com tempo médio de 163 dias, após a primeira dose e 85 dias após a segunda. Após a cicatrização, os doentes foram controlados por um período médio de 8,4 meses variando entre 3 e 19 meses. A observação mostrou que a cura das lesões é de forma mais retardada, podendo em muitos casos haver uma recrudescência das lesões e, em alguns casos, uma segunda dose acelera a cura.

Quantificação de anticorpos diftéricos em cobaias: I - persistência do título de anticorpos séricos em animais inoculados com uma dose de toxóide diftérico

Foi estudado o comportamento da cinética de anticorpogénese em cobaias inoculadas com uma dose de toxóide diftérico precipitado pelo alúmen. Paralelamente, foi estudada a dinâmica da imunidade passiva naturalmente transmitida aos filhotes. Em cobaias vacinadas com uma dose de antígeno, foi verificado que a síntese de antitoxina diftérica persiste, em títulos detectáveis, até 36 meses após. Os anticorpos transferidos, passivamente, da mãe vacinada para os filhotes atingiram, nestes, concentrações plasmáticas superiores, sendo que a imunidade perdurou em títulos detectáveis até cerca de três meses de idade dos mesmos.