Corridors of migrating neurons in the human brain and their decline during infancy

The subventricular zone of many adult non-human mammals generates large numbers of new neurons destined for the olfactory bulb. Along the walls of the lateral ventricles, immature neuronal progeny migrate in tangentially oriented chains that coalesce into a rostral migratory stream (RMS) connecting the subventricular zone to the olfactory bulb. The adult human subventricular zone, in contrast, contains a hypocellular gap layer separating the ependymal lining from a periventricular ribbon of astrocytes. Some of these subventricular zone astrocytes can function as neural stem cells in vitro, but their function in vivo remains controversial. An initial report found few subventricular zone proliferating cells and rare migrating immature neurons in the RMS of adult humans. In contrast, a subsequent study indicated robust proliferation and migration in the human subventricular zone and RMS. Here we find that the infant human subventricular zone and RMS contain an extensive corridor of migrating immature neurons before 18 months of age but, contrary to previous reports, this germinal activity subsides in older children and is nearly extinct by adulthood. Surprisingly, during this limited window of neurogenesis, not all new neurons in the human subventricular zone are destined for the olfactory bulb--we describe a major migratory pathway that targets the prefrontal cortex in humans. Together, these findings reveal robust streams of tangentially migrating immature neurons in human early postnatal subventricular zone and cortex. These pathways represent potential targets of neurological injuries affecting neonates.     

AN INVESTIGATION OF THE RELATION BETWEEN COTTON FIBRE PROPERTIES AND YARN QUALITY BY USING HIGH VOLUME INSTRUMENT(HVI)SYSTEM

The objective of this paper is to establish reliable prediction equations relating cotton fibreproperties measured by HVI system and yarn quality,A useful statistical method is adopted for de-veloping a multiple regression model interpreting the relation between the data of Spinlab HVIfibre properties and quality parameters of yarn STQ (Strength Tex Quotient).The percent relativecontribution of a fibre property with respect of STQ is also assessed.The results show that the totalcontribution of the HVI measured fibre properties can account for 77.4% of known variation ofyarn STQ.The main feature of the approach is its flexibility in accommodating all fibre properties.The examination of regression equation showed that it could be well applied to predict STQ ofyarns spun from the same spinning system,but,for different spinning systems and also for yarns ofdifferent linear density,modification of the equation would be needed.     

The agar gel-diffusion technique as a method of differentiating mosquito eggs

Zusammenfassung Bei Agargel-Diffusionstechnik zeigenCulex-pipiens-fatigans-Eier mindestens vier deutlich voneinander unterscheidbare Präzipitationslinien, wenn sie mit homologem Antiserum reagierten. Eier vonArmigeres subalbatus, Aedes aegypti undAedes albopictus hingegen zeigten nur eine einzige Linie bei Reaktion mit dem gleichenCulex-Antiserum.     

Effect of hypoxia on human adipose-derived mesenchymal stem cells and its potential clinical applications

Human adipose-derived mesenchymal stem cells (hASCs) are an ideal cell source for regenerative medicine due to their capabilities of multipotency and the readily accessibility of adipose tissue. They have been found residing in a relatively low oxygen tension microenvironment in the body, but the physiological condition has been overlooked in most studies. In light of the escalating need for culturing hASCs under their physiological condition, this review summarizes the most recent advances in the hypoxia effect on hASCs. We first highlight the advantages of using hASCs in regenerative medicine and discuss the influence of hypoxia on the phenotype and functionality of hASCs in terms of viability, stemness, proliferation, differentiation, soluble factor secretion, and biosafety. We provide a glimpse of the possible cellular mechanism that involved under hypoxia and discuss the potential clinical applications. We then highlight the existing challenges and discuss the future perspective on the use of hypoxic-treated hASCs.     

The application of fluorescent-antibody test to cysts ofEntamoeba invadens

Zusammenfassung Die Methode fluoreszierender Antikörper wurde zur Darstellung von Blasen beiEntamoeba invadens benützt. Sowohl mit nativen, wie auch mit fixierten Zellen konnte eine befriedigende Reaktion erzielt werden. Formalin erwies sich als günstigstes Fixationsmittel.     

The lytic activity of immune and non-immune rabbit serum onBalantidium coli

Résumé Des bacillesBalantidium coli ont été dissous après avoir été exposés à l'action du sérum de lapin immunisé et non-immunise. L'activité lytique des 2 sérums se perd par inactivation thermique à 56°C pendant 30 min, mais elle est restorée dans les 2 sérums après adjonction de sérum de cobaye normal.