Significance Found in most eukaryotic cells, a centriole is a cylindrically shaped subcellular structure that plays an important role in various cellular processes, including mitotic spindle formation and chromosome segregation. Centriole duplication occurs only once per cell cycle, thus ensuring accurate control of centriole numbers to maintain genomic integrity. Although a growing body of evidence suggests that a Ser/Thr protein kinase, polo-like kinase 4 (Plk4), is a key regulator of centriole duplication, how Plk4 is recruited to centrosomes remains largely unknown. Here we showed that Plk4 dynamically localizes to distinct subcentrosomal regions by interacting with two hierarchically regulated scaffolds, Cep192 and Cep152. Highlighting the importance of these interactions, mutational disruption of either one of these interactions was sufficient to cripple Plk4-dependent centriole biogenesis.

Lipopolysaccharide (LPS) increases the production of interleukin-12 (IL-12

Numerous viruses, including influenza virus, measles virus, Hantavirus, adenovirus, herpesviruses, varicella-zoster virus, cytomegalovirus, and Epstein-Barr virus, can cause lower respiratory tract infection in adults. Viral pneumonia in adults can be classified into two clinical groups: so-called atypical pneumonia in otherwise healthy hosts and viral pneumonia in immunocompromised hosts. Influenza virus types A and B cause most cases of viral pneumonia in immunocompetent adults. Immunocompromised hosts are susceptible to pneumonias caused by cytomegalovirus, herpesviruses, measles virus, and adenovirus. The radiographic findings, which consist mainly of patchy or diffuse ground-glass opacity with or without consolidation and reticular areas of increased opacity, are variable and overlapping. Computed tomographic findings, which are also overlapping, consist of poorly defined centrilobular nodules, ground-glass attenuation with a lobular distribution, segmental consolidation, or diffuse ground-glass attenuation with thickened interlobular septa. The radiologic findings reflect the variable extents of the histopathologic features: diffuse alveolar damage (intraalveolar edema, fibrin, and variable cellular infiltrates with a hyaline membrane), intraalveolar hemorrhage, and interstitial (intrapulmonary or airway) inflammatory cell infiltration. Clinical information such as patient age, immune status, community outbreaks, symptom onset and duration, and presence of a rash remain important aids in diagnosis of viral causes.

No abstract