Comparison of the pathogenesis of the highly passaged MCMV Smith strain with that of the low passaged MCMV HaNa1 isolate in BALB/c mice upon oronasal inoculation

Murine cytomegalovirus (MCMV) Smith strain is widely used in mouse models to study HCMV infections. Due to high serial passages, MCMV Smith has acquired genetic and biological changes. Therefore, a low passaged strain would be more relevant to develop mouse models. Here, the pathogenesis of an infection with MCMV Smith was compared with that of an infection with a low passaged Belgian MCMV isolate HaNa1 in BALB/c adult mice following oronasal inoculation with either a low (10(4) TCID50/mouse) or high (10(6) TCID50/mouse) inoculation dose. Both strains were mainly replicating in nasal mucosa and submandibular glands for one to two months. In nasal mucosa, MCMV was detected earlier and longer (1-49 days post inoculation (dpi)) and reached higher titers with the high inoculation dose compared to the low inoculation dose (14-35 dpi). In submandibular glands, a similar finding was observed (high dose: 7-49 dpi; low dose: 14-42 dpi). In lungs, both strains showed a restricted replication. In spleen, liver and kidneys, only the Smith strain established a productive infection. The infected cells were identified as olfactory neurons and sustentacular cells in olfactory epithelium, macrophages and dendritic cells in NALT, acinar cells in submandibular glands, and macrophages and epithelial cells in lungs for both strains. Antibody analysis demonstrated for both strains that IgG(2a) was the main detectable antibody subclass. Overall, our results show that significant phenotypic differences exist between the two strains. MCMV HaNa1 has been shown to be interesting for use in mouse models in order to get better insights for HCMV infections in immunocompetent humans

Managing neonatal bowel obstruction: clinical perspectives

Sarah M Desoky,1 Ranjit I Kylat,2 Unni Udayasankar,1 Dorothy Gilbertson-Dahdal1 1Department of Medical Imaging, University of Arizona College of Medicine, Tucson, AZ, USA; 2Division of Neonatal-Perinatal Medicine, Department of Pediatrics, University of Arizona College of Medicine, Tucson, AZ, USA Abstract: Neonatal intestinal obstruction is a common surgical emergency and occurs in approximately 1 in 2,000 live births. The causes of obstruction are diverse with varied embryological origins, and some underlying etiologies are not yet well described. Some findings of neonatal bowel obstruction can be detected prenatally on ultrasound imaging. The obstruction is classified as “high” when the level of obstruction is proximal to the ileum, and “low” when the level of obstruction is at the ileum or colon. Early diagnosis of the type of intestinal obstruction and localization of the obstructive bowel segment guides timely and appropriate management of the underlying pathologic entity. Neonatal bowel obstructions are ideally managed at specialized centers with a large volume of neonatal surgery and dedicated pediatric surgical and anesthesia expertise. Although surgical intervention is necessary in most cases, initial management strategies often target underlying metabolic, cardiac, or respiratory abnormalities. Imaging plays a key role in early and accurate diagnosis of the abnormalities. When bowel obstruction is suspected clinically, initial imaging workup usually involves abdominal radiography, which may direct further evaluation with fluoroscopic examination such as upper gastrointestinal (UGI) contrast study or contrast enema. This article provides a comprehensive review of clinical and radiological features of common and less common causes of intestinal obstruction in the neonatal age group, including esophageal atresia, enteric duplication cysts, gastric volvulus, congenital microgastria, hypertrophic pyloric stenosis, duodenal atresia, intestinal malrotation, intussusception, intestinal atresia, meconium ileus, functional immaturity of the colon, Hirschsprung disease, and anorectal malformation. The embryology, epidemiology, clinical presentation, and brief medical and surgical management of each is described. Keywords: neonatal, bowel, intestinal, obstructio