Effects of chronic immobilization stress on biokinetics and dosimetry of 67Ga in a murine model.

The aim of this work is to determine the effect of chronic immobilization stress on kinetics and dosimetry of 67Ga in a mouse model. A control group (CG) and a stress group (SG), each with 15 mice, were included in the study, and the latter group was subjected to a chronic immobilization stress model 2 h daily for 14 consecutive days. At day 13, 67Ga-citrate was administered intraperitoneally (11.24 ± 0.44 MBq) to each mouse. Then, sets of three mice were obtained sequentially at 24, 36, 48, 60 and 72 h, in which the radionuclide activity was measured with an activity counter. The 67Ga biokinetic data showed a fast blood clearance in the SG, with a mean residence time of 0.06 h. The calculated mean radiation absorbed doses were: liver (2.45 × 10-03 Gy), heart (3.17 × 10-04 Gy) and kidney (1.88 × 10-04 Gy) in the SG. The results show that stress reduced weight gain by approximately 13% and also increased adrenal gland weight by 26%. On the other hand, chronic stress accelerates 67Ga clearance after 24 h compared to normal conditions. It is concluded that murine organisms under chronic immobilization stress have higher gallium-67 clearance rates, decreasing the cumulated activity and absorbed dose in all organs.

Permanent Indwelling Transmural Stents for Endoscopic Treatment of Patients With Disconnected Pancreatic Duct Syndrome: Long-term Results.

INTRODUCTION: Disconnected pancreatic duct syndrome (DPDS) is defined as the complete disruption of the main pancreatic duct, the result are peripancreatic fluid collections or pancreatic leaks. The aim of this study was to report the results of derivative endoscopic treatment of DPDS in a long-term follow-up period. PATIENTS AND METHODS: We performed a retrospective analysis of prospectively collected data. Endoscopic treatment consisted of transmural drainage with 2 double pigtail plastic stents (7 F and 4 cm) deployed under endoscopic ultrasound guidance. RESULTS: In total, 21 patients were included in our study. There were 15 (71%) men and the median age was 36 years (range, 23 to 86 y). The principal etiology of DPDS was acute pancreatitis. A total of 20 (95.2%) patients were diagnosed with DPDS by endoscopic pancreatography and only 1 (4.8%) patient by magnetic resonance cholangiopancreatography (MRCP). The median follow-up time was 28 months (range, 7 to 76 mo). Technique success was 100% and initial clinical success was 80.9% (17/21). Three (17.6%) of these patients required a new endoscopic procedure with success in all cases. During follow-up, 11 (52%) patients developed diabetes mellitus and 3 patients (14%) developed exocrine pancreatic insufficiency. There were 5 (15%) patients with complications. CONCLUSION: According to our data, endoscopic treatment with the placement of a permanent indwelling transmural stents is a useful and safe tool for the treatment of DPDS.

Advances and challenges of incorporating ecosystem services into impact assessment.

An ecosystem services approach (ESA) to assess the environmental and social impacts of projects is a conceptual innovation that contributes to overcome two widely acknowledged deficiencies of impact assessment (IA): integration of knowledge areas and participation of affected communities. This potential was demonstrated through a practical application to a large mining project, showing evidence of advances in relation to current practice and identifying challenges. Data was obtained from the environmental impact study of the reviewed project and its supplements; additional data to fulfill the needs of the ESA were collected using rapid appraisal techniques. Results show that the ESA provides: (i) a more effective scoping; (ii) a contribution to delimitate the study area; (iii) a more detailed identification of impacts; (iv) a determination of significance inclusive of the perspective of affected communities; (v) a design of mitigation focused on human well-being. The challenges of using the ESA fall into two groups: the limitations inherent to the concept and those that can be overcome by furthering research and advancing practical applications. This research added evidence to previous studies showing that incorporating ecosystem services into IA can improve practice.

Biokinetics, radiopharmacokinetics and estimation of the absorbed dose in healthy organs due to Technetium-99m transported in the core and on the surface of reconstituted high-density lipoprotein nanoparticles.

The development of rHDL-radionuclide theragnostic systems requires evaluation of the absorbed doses that would be produced in healthy tissues and organs at risk. Technetium-99m is the most widely used radionuclide for diagnostic imaging, therefore, the design of theragnostic reconstituted high density-lipoprotein (rHDL) nanosystems labeled with Technetium-99m offers multiple possibilities. OBJECTIVE: To determine the biokinetics, radiopharmacokinetics and estimate the absorbed doses induced in healthy organs by Technetium-99m transported in the core and on the surface of rHDL. METHODS: Biokinetic and radiopharmacokinetic models of rHDL/[99mTc]Tc-HYNIC-DA (Technetium-99m in the core) and [99mTc]Tc-HYNIC-rHDL (Technetium-99m on the surface) were calculated from their ex vivo biodistribution in healthy mice. Absorbed doses were estimated by the MIRD formalism using OLINDA/EXM and LMFIT softwares. RESULTS: rHDL/[99mTc]Tc-HYNIC-DA and [99mTc]Tc-HYNIC-rHDL show instantaneous absorption in kidney, lung, heart and pancreas, with slower absorption in spleen. rHDL/[99mTc]Tc-HYNIC-DA is absorbed more slowly in the intestine, while [99mTc]Tc-HYNIC-rHDL is absorbed more slowly in the liver. The main target organ for rHDL/[99mTc]Tc-HYNIC-DA, which is hydrophobic in nature, is the liver, whereas the kidney is for the more hydrophilic [99mTc]Tc-HYNIC-rHDL. Assuming that 925 MBq (25 mCi) of Technetium-99m, carried in the core or on the surface of rHDL, are administered, the maximum tolerated doses for the organs of greatest accumulation are not exceeded. CONCLUSION: Theragnostic systems based on 99mTc-labeled rHDL are safe from the dosimetric point of view. The dose estimates obtained can be used to adjust the 99mTc-activity to be administered in future clinical trials.

Influence of occlusal stabilization splints and soft occlusal splints on the electromyographic pattern, in basal state and at the end of six weeks treatment in patients with bruxism.

The aim of this study is to assess the electrical activity generated in temporal and masseter muscles during voluntary muscular contraction of patients with bruxism, as a result of the use of two types of occlusal splints (occlusal stabilization splint and soft occlusal splint) in which 2 groups of 8 patients were evaluated -12 women and four men aged 19 to 40 years, who used a single type of occlusal splint for 46 to 60 days. The splints were made from sheets of rigid acetate plus heat-cured acrylic (occlusal stabilization splint, control group) and sheets of flexible acetate (soft occlusal splint, experimental group). Two electromyographic tests (EMG) were performed on each patient; one before placing the splint and another at the end of the treatment. The statistical analysis used was computerized variance ANOVA analysis with F distribution (P < or = 0.025). In the control group, muscle electrical activity increased significantly in 5 patients and decreased slightly in 3. In the experimental group, there was considerable reduction of such activity in 6 patients and a slight increase in 2. There is a statistically significant difference (P < or = 0.025) between the muscle electrical activity generated in the control group and in the experimental group. The increase in muscle electrical activity in the control group may have been due to a neuromuscular recovery process; while the decrease in the experimental group might have been due to a negative or decremental process of muscular organization to prevent the recruitment of new motor units. Occlusal stabilization splints are therefore considered better than soft occlusal splints.

Proposed Legislation to Mine Brazil's Indigenous Lands Will Threaten Amazon Forests and Their Valuable Ecosystem Services.

A recent proposal to regulate mining within Indigenous Lands (ILs) threatens people and the unique ecosystems of Brazil's Legal Amazon. Here, we show that this new policy could eventually affect more than 863,000 km2 of tropical forests-20% more than under current policies-assuming all known mineral deposits will be developed and impacts of mining on forests extend 70 km from lease boundaries. Not only are these forests home to some of the world's most culturally diverse communities, they also provide at least US $5 billion each year to the global economy, producing food, mitigating carbon emissions, and regulating climate for agriculture and energy production. It is unclear whether new mines within ILs will be required to compensate for their direct and indirect environmental and social impacts but failing to do so will have considerable environmental and social consequences.

Hepatic angiomyolipoma resected by eft hepatectomy: Case report.

El angiomiolipoma hepático es un tumor mesenquimatoso infrecuente perteneciente al grupo de los PEComas (Perivascular Epithelioid Cells), que cuenta con un potencial maligno indeterminado. Los síntomas clínicos son inespecíficos, siendo las características radiológicas principales la alta vascularización de la lesión y la presencia de tejido adiposo macroscópico. Presentamos un caso clínico de un angiomiolipoma hepático izquierdo diagnosticado por tomografía computada de manera incidental y asintomático en una paciente sin antecedentes de importancia que se sometió a hepatectomía lateral izquierda con resección completa del tumor, el cual fue negativo para malignidad y sin complicaciones.Hepatic angiomyolipoma is a mesenchymal tumor known as PEComas (Perivascular Epithelioid Cells) with unknown malignancy pattern. We present a case report of left hepatic angiomyolipoma diagnoses by computed tomography in an asymptomatic patient with no previous medical diseases. The tumor was complete resected during a left lateral hepatectomy with no complications and final histologic report was negative to cancer.

Assessing the evolution of sustainability reporting in the mining sector.

Since the 1990s several large companies have been publishing nonfinancial performance reports. Focusing initially on the physical environment, these reports evolved to consider social relations, as well as data on the firm's economic performance. A few mining companies pioneered this trend, and in the last years some of them incorporated the three dimensions of sustainable development, publishing so-called sustainability reports. This article reviews 31 reports published between 2001 and 2006 by four major mining companies. A set of 62 assessment items organized in six categories (namely context and commitment, management, environmental, social and economic performance, and accessibility and assurance) were selected to guide the review. The items were derived from international literature and recommended best practices, including the Global Reporting Initiative G3 framework. A content analysis was performed using the report as a sampling unit, and using phrases, graphics, or tables containing certain information as data collection units. A basic rating scale (0 or 1) was used for noting the presence or absence of information and a final percentage score was obtained for each report. Results show that there is a clear evolution in report's comprehensiveness and depth. Categories "accessibility and assurance" and "economic performance" featured the lowest scores and do not present a clear evolution trend in the period, whereas categories "context and commitment" and "social performance" presented the best results and regular improvement; the category "environmental performance," despite it not reaching the biggest scores, also featured constant evolution. Description of data measurement techniques, besides more comprehensive third-party verification are the items most in need of improvement.