ABSTRACT
We introduce an autonomous oxygen concentrator that was designed in Peru to fight the oxygen shortage produced worldwide as a consequence of the COVID-19 pandemic. Oxygen concentrators represent a suitable and favorable option for administering this gas at the patient's bedside in developing countries, especially when cylinders and tubed systems are unavailable or when access to them is restricted by lack of accessories, inadequate power supply, or shortage of qualified personnel. Our system uses a pressure swing adsorption technique to provide oxygen to patients at a flow rate of up to 15 l/min ± 1,5 l/min and a concentration of 93 % ± 3 %, offering robustness, safety and functionality. The quality measurements obtained from the validation process demonstrate repeatability and accuracy. The complete design files are provided in the source file repository to facilitate oxygen concentrator production in low and middle income countries, where access to oxygen is still a major problem even after the pandemic. Oxygen is part of the World Health Organization Model List of Essential Medicines and is perhaps the only medicine that has no substitute. This device can provide a reliable supply of oxygen for critically ill patients and improve their chances of survival.
ABSTRACT
BACKGROUND: Infection by Helicobacter pylori (H. pilory) affects 50% of the world population. Simple methods for its detection are now available. OBJECTIVES: To identify H. pylori by using a monoclonal coproantigen technique in paediatric patients, and to determine its association with gastrointestinal diseases. MATERIALS AND METHODS: The study included a total of 110 subjects aged 1 to 18 years. The study variables included: Family history of gastrointestinal disease, age, gender, gastrointestinal symptoms, as well as apparently healthy (asymptomatic) subjects. The monoclonal coproantigen test was performed on stool samples. Two groups, I symptomatic (n=29), and II asymptomatic (n=81) were compared using parametric and non-parametric statistics. RESULTS: Of the 110 patients, 59 (54%) were male. The relationship between a family history of gastritis and a positive for H. pylori, was significant for mothers (p<0.0005), fathers (p<0.0001), and paternal grandfathers (p<0.0001). It was significant for gastric cancer in maternal grandparents (p<0.0178) and paternal grandparents (p<0.0092). The monoclonal coproantigen test was positive in 31 (28.2%) of the subjects. All were positive in group I, and only 2 in group II. A significant positive association was observed between H. pylori and various signs and symptoms, such as epigastric pain (p<0.001), recurrent peri-umbilical pain (p<0.001), bloating (p=0.016), heartburn (p=0.0007), nausea (P=0.0061), diarrhoea (p=0.0389), and constipation (p=0.0019). CONCLUSIONS: H. pylori detection, was positive in 28% of both groups, and showed significant relationships with family gastrointestinal diseases and gastrointestinal symptoms.
