Does a bolus of mannitol initially aggravate intracranial hypertension? A study at various PaCO2 tensions in dogs

In two groups of anaesthetized dogs, with (n = 28) or without (n = 28) induced intracranial hypertension, we compared the effects on intracranial pressure (ICP) of the rapid administration of mannitol 2 g kg-1 i.v. at PaCO2 2.7, 4.0, 5.3, and 6.7 kPa (n = 7). In dogs with no induced intracranial hypertension, ICP increased during the administration of mannitol, reached a peak at 2 min after infusion, and then gradually decreased (P less than 0.05). More marked changes in ICP were observed in response to higher values of PaCO2 (P less than 0.05). In dogs with induced intracranial hypertension, the rapid infusion of mannitol caused an exponential decrease in ICP, without initial increase, which was significantly steeper at higher values of PaCO2 (P less than 0.05). This was followed by a more gradual decrease which achieved pre-balloon inflation values 10 min after infusion. We postulate that the absence of the initial increase in ICP is the result of a concomitant decrease in arterial pressure, a reduction in the volume-pressure response of the brain, the failure of mannitol to dilate further the cerebral arterial vascular bed and a hitherto unnoticed early water-drawing effect. Our study confirmed the safety of rapidly expanding the circulating blood volume with mannitol in circumstances of increased ICP in dogs

Identification par transport retrograde du Fast Blue, et caracterisation par immunohistofluorescence des neurones efferents olivocochleaires du rat et du cobaye

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Enteric Protoz Associated with Acute Diarrhea in Hospitalized Children in Qatar

Diarrhea is the passage of three or more watery stool in a period of 24 hours (WHO, 2013). Types of diarrhea include acute watery diarrhea, acute bloody diarrhea known as dysentery and persistent diarrhea (WHO, 2013). It is caused by an infection of different pathogens including bacteria, viruses and parasites through fecal-oral transmission (WHO, 2013). Moreover, it can also be caused by food intolerance to certain food substances and as a side effect of certain medications such as laxatives (Burton & Ludwig, 2015). Diarrhea occurrence is most frequently associated with conditions of poor environmental sanitation and hygiene, poverty, inadequate water supply and limited education (Nelson & Masters, 2014). Worldwide, acute diarrhea disease is considered as the second cause of mortality and morbidity in children according to the World Health Organization (WHO, 2013). In 2012, WHO reported 1.9 million diarrheal cases in children aged under the age of five accounting for 18% of all deaths. The clinical manifestations of diarrhea in pediatric patients include abdominal pain, nausea, vomiting and fever (WGO, 2012 & Maas et al., 2014). Diarrhea in children can lead to many consequences such as malnutrition, diminished growth and impaired cognitive development (WGO, 2012). Severe diarrhea can also result in life-threatening dehydration (Galvao et al., 2013). Thus it is important to replace the fluid and electrolytes by oral rehydration solution. Diarrhea is usually self-limiting. However, in cases of diarrhea persisting for longer than 1 week, broad-spectrum antimicrobial agents are administered to treat bacterial and parasitic infection (Koletzko & Osterrieder, 2009). Intestinal protozoa that are most commonly associated with diarrhea in children include Blastocyst, Dientamoeba fragilis, Giardia lamblia, Cryptosporidium species and Entamoeba species (Maas et al., 2014). Having updated information about the prevalence of these protozoan parasitic infections will aid in faster diagnosis and thus treatment. - Research question and objectives: Research Question: What are the most common protozoa and the risk factors for diarrhea in children under the age of 15 admitted to Hamad Medical Corporation (HMC).qscienc