Fluvoxamine moderates reduced voluntary activity following chronic dexamethasone infusion in mice via recovery of BDNF signal cascades

Major depression is a complex disorder characterized by genetic and environmental interactions. Selective serotonin reuptake inhibitors (SSRIs) effectively treat depression. Neurogenesis following chronic antidepressant treatment activates brain derived neurotrophic factor (BDNF) signaling. In this study, we analyzed the effects of the SSRI fluvoxamine (Flu) on locomotor activity and forced-swim behavior using chronic dexamethasone (cDEX) infusions in mice, which engenders depression-like behavior. Infusion of cDEX decreased body weight and produced a trend towards lower locomotor activity during darkness. In the forced-swim test, cDEX-mice exhibited increased immobility times compared with mice administered saline. Flu treatment reversed decreased locomotor activity and mitigated forced-swim test immobility. Real-time polymerase chain reactions using brain RNA samples yielded significantly lower BDNF mRNA levels in cDEX-mice compared with the saline group. Endoplasmic reticulum stress-associated X-box binding protein-1 (XBP1) gene expression was lower in cDEX-mice compared with the saline group. However, marked expression of the XBP1 gene was observed in cDEX-mice treated with Flu compared with mice given saline and untreated cDEX-mice. Expression of 5-HT2A and Sigma-1 receptors decreased after cDEX infusion compared with the saline group, and these decreases normalized to control levels upon Flu treatment. Our results indicate that the Flu moderates reductions in voluntary activity following chronic dexamethasone infusions in mice via recovery of BDNF signal cascades.

Removable splint with locking attachments for maxillary distraction osteogenesis with the RED system

The external traction hooks of the intraoral splint used to control traction forces applied to the maxilla with the rigid external distraction system represent a major barrier to surgical procedures. The purpose of this article is to introduce a removable intraoral splint with locking attachments that can be placed post-surgically immediately before distraction, facilitating surgery and consequently reducing the operative time. Fifteen cleft lip and palate patients underwent maxillary distraction osteogenesis using a rigid external distraction device in combination with the proposed removable splint that was fixed onto the maxillary teeth to provide anchorage. Initial records showed severe maxillary hypoplasia and negative overjet. The removable splint was fabricated using 1.5-mm diameter stainless-steel rigid orthodontic wires soldered to the locking attachments (Y&B Products LP, Chiang Mai, Thailand), making possible its placement post-surgically. Stable splint fixation was achieved prior to the distraction procedure and the desired treatment goals were reached. No complications inserting or removing the splint post-surgically, including pain or discomfort, were observed. The use of the removable splint with locking attachments has proved to be a highly effective fixation approach to manage the severely hypoplastic maxilla, eliminating lip constraints resulting from scarring, and allowing for easier, more deliberate and careful dissection.

[Hantavirus pulmonary syndrome in Buenos Aires Province]

In Argentina the first Hantavirus Pulmonary Syndrome (HPS) cases were characterized in 1995. Since then, Argentina is the country with the highest number of notified cases in South America. The disease is distributed in Northern, Southern and Central regions of the country, being Buenos Aires the most affected province from the Central region. In this study, we present seasonal and geographical distribution of HPS cases in Buenos Aires province, the association with diverse viral lineages and the serological characteristics of hantavirus infection in the period from 1997 up to the first semester of the year 2000. An increase in the number of HPS cases was observed up to 1999 and a gradual mortality decrease in the whole period. The cases occurred between spring and autumn, with a maximum peak in summer. The serological response was studied in 58 HPS confirmed cases at different times after the onset of symptoms. The cases were distributed between 27 localities, in two different directions from the city of Buenos Aires: South-southwest and North-northeast. More than 52% of the cases occurred in La Plata and neighboring localities. The viral genomes from 39 cases were all characterised as Andes virus (AND): AND Cent Plata 16%; AND Cent 21% and AND Cent Bs.As. 60%. Andes virus lineages only cocirculated in La Plata city. These results will contribute to establish a risk map leading to the implementation of improved strategies of prevention.

Thermomechanical analysis of collagen crosslinking in the developing lamb pericardium

In a developing lamb model, we have used hydrothermal isometric tension (HIT) techniques to assess collagen crosslink stability and its contribution to the mechanical properties of the pericardium. Strip samples of tissue were either: (i) heated to a 90 degrees C isotherm or (ii) heated in 5 degrees C increments between 60-90 degrees C and then 93 and 97 degrees C isotherms. The half-life of stress relaxation associated with peptide bond hydrolysis (t1/2) was calculated at each isotherm. The activation energy, Eact, for the hydrolysis-associated relaxation process was also calculated using the data from the stepwise HIT tests--a technical improvement which significantly reduces the experimental time required to develop statistically valid measurements. Crosslinking in the pericardium increased during development and was demonstrated both by thermoelasticity and by resistance to enzymatic solubilization. We observed greater conversation to thermally stable crosslinks upon maturation, the ratio of the NaBH4-stabilized/unstabilized half-lives peaking at 21 days postnatal. Whereas tissue from lambs (119 day fetal, and 3 day and 21 day postpartum) showed an early maximum and rapid decay of force, NaBH4 stabilization significantly increased thermal stability and yielded profiles similar to those in adult tissue.

Human wakefulness and biological rhythms after birth

Both a sleep-wakefulness cycle and a basic rest-activity cycle were observed in 20 normal infants left undisturbed for ten hours following birth. Behavioral wakefulness occurred immediately following delivery and in between sleep periods despite the lack of feeding and other intervention. Medication given to mothers during labor resulted in decreased amounts of infant wakefulness and increased amounts of quiet (non rapid eye movement) sleep.