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A new flow batch (FB) system for chemical vapor generation (CVG) is proposed for mercury (Hg) determination in fish. An inductively coupled plasma mass spectrometer was used as a detector. Low-cost peristaltic mini pumps were used to propel the solutions and different configurations of FB systems (reactor/gas/liquid separator) were studied. The proposed configuration of the FB-CVG system allows good sensitivity, low limit of detection (LOD) and low consumption of reagents and sample solutions. In summary, only 1 mL of reductant, 1 mL of acid and 0.16 mL of sample are needed. The proposed method has good linearity, precision (better than 5 %), LOD of 0.008 μg g -1 and LOQ of 0.012 μg g -1 , and high sample throughput, allowing 90 measurements/h. The accuracy of the method was evaluated through the analysis of a certified reference material (DOLT-4 Dogfish Liver), whose result is in good agreement with certified value (t-test with 95 % confidence level) and the quantification limit meets current legislations, of 1.0 μg g -1 (Brazil) and 0.3 μg g -1  (EU). In addition, analyte recovery test was done, where Hg recovery was better than 95 %, demonstrating the good analytical performance of the method. To demonstrate the applicability of the method, five samples of fish tissue (muscle) were analyzed. The proposed FB-CVG system, in addition to being low cost, is robust and requires only the volume of reagents necessary for Hg vapor generation, producing a very low amount of waste. It can be concluded that the proposed system can be used for routine analysis for Hg determination in fish tissue. It is worth noting that with the appropriate adjustments, the system can be coupled to different Hg detectors., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Copper (Cu) and Zinc (Zn) are required in small concentrations for metabolic functions, but are also toxic. There is a great concern about soil pollution by heavy metals, which may exposure the population to these toxicants, either by inhalation of dust or exposure to toxicants through ingestion of food derived from contaminated soils. In addition, the toxicity of metals in combination is questionable, as soil quality guidelines only assess them separately. It is well known that metal accumulation is often found in the pathologically affected regions of many neurodegenerative diseases, including Huntington's disease (HD). HD is caused by an autosomal dominantly inherited CAG trinucleotide repeat expansion in the huntingtin (HTT) gene. This results in the formation of a mutant huntingtin (mHTT) protein with an abnormally long polyglutamine (polyQ) repeat. The pathology of HD results in loss of neuronal cells, motor changes, and dementia. Rutin is a flavonoid found in various food sources, and previous studies indicate it has protective effects in HD models and acts as a metal chelator. However, further studies are needed to unravel its effects on metal dyshomeostasis and to discern the underlying mechanisms. In the present study, we investigated the toxic effects of long-term exposure to copper, zinc, and their mixture, and the relationship with the progression of neurotoxicity and neurodegeneration in a C. elegans-based HD model. Furthermore, we investigated the effects of rutin post metal exposure. Overall, we demonstrate that chronic exposure to the metals and their mixture altered body parameters, locomotion, and developmental delay, in addition to increasing polyQ protein aggregates in muscles and neurons causing neurodegeneration. We also propose that rutin has protective effects acting through mechanisms involving antioxidant and chelating properties. Altogether, our data provides new indications about the higher toxicity of metals in combination, the chelating potential of rutin in the C. elegans model of HD and possible strategies for future treatments of neurodegenerative diseases caused by the aggregation of proteins related to metals., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Infectious disease outbreaks occurred many times in the past and are more likely to happen in the future. In this paper the problem of allocating and scheduling limited multiple, identical or non-identical, resources employed in parallel, when there are several infected areas, is considered. A heuristic algorithm, based on Shih's (1974) and Pappis and Rachaniotis' (2010) algorithms, is proposed as the solution methodology. A numerical example implementing the proposed methodology in the context of a specific disease outbreak, namely influenza, is presented. The proposed methodology could be of significant value to those drafting contingency plans and healthcare policy agendas., (© Systems Engineering Society of China and Springer-Verlag Berlin Heidelberg 2017.)

Three children were operated upon for congenital epithelial cysts of the spleen in the five-year period 1983-1987. Their mean age was 9.8 +/- 2.3 years. Two of them were boys. They comprise 1.6% of the surgical pathology of the spleen in our hospital, which is a Reference Centre for congenital haemolytic diseases. Two of the children had been suffering from intermittent colic pain in the left hypochondrium with a tender palpable mass for a short while to the present day. The third patient was asymptomatic; a splenic cyst with calcification of its wall was accidentally revealed by a plain x-ray of the abdomen. Contrast gastrointestinal studies and intravenous pyelography helped us with the diagnosis; they indicated a splenic mass that caused visceral displacement adjacent to the spleen. Ultrasonography proved the cystic nature of the enlargement of the spleen in all the cases. Marsupialization was performed in one patient and removal of the cysts in the other two. All three patients were followed up and re-checked 1-5 years postoperatively (May-June 1988). In one boy who underwent removal of the cyst four years ago, recurrence of the splenic cyst was revealed by ultrasonography, CT scan and radionuclide scan. Subtotal splenectomy was performed. The remaining upper pole is supplied with blood by the short gastric arteries. The recurrence was attributed to coexistence of invisible tiny cysts that had remained in the splenic tissue after the dissection of the major cyst during the previous operation. Subtotal splenectomy is an acceptable alternative procedure for splenic cysts.

A case of bilateral nephroblastoma in a horseshoe kidney is presented. It is the second to be reported in the international literature.

Since 1973, 419 children (233 boys, 186 girls) with chronic haemolytic anaemia (mean age, 10.2 +/- 3.5 years) have been splenectomised. Fifty-three (12.6%) have also been cholecystectomised because of cholelithiasis. Between 1973 and 1982, cholecystectomy and splenectomy were performed at the same time in symptomatic patients. Later, between 1983 and 1987, cholecystectomy was also performed in clinically asymptomatic patients with positive sonographic findings. In the first period, 11 thalassaemic patients (45.8%) were cholecystectomised a short period after splenectomy (in two cases, only 2 and 3 weeks later). Between 1983 and 1987, when asymptomatic patients with cholelithiasis were screened by sonography, simultaneous cholecystectomy and splenectomy were performed in 13.6% of the patients with thalassaemia, in 41% of the patients with sickle cell or microdrepanocytic disease, and in 22.2% of the patients with spherocytosis. As there is a high incidence of asymptomatic cholelithiasis and hypersplenism in patients with chronic haemolytic anaemia, screening for gallstones should precede splenectomy. Simultaneous cholecystectomy should be performed in patients with cholelithiasis.