An Atypical Case of Hemoptysis.

Hemoptysis, a common sign of diffuse alveolar hemorrhage, can be caused by multiple factors, both infectious and noninfectious. A 45-year-old male with hypertension, obstructive sleep apnea, and stage IV pulmonary sarcoidosis with cardiac involvement, presented with a two-month history of cough and acute nonmassive hemoptysis with hypoxia. A chest CT showed ground glass consolidation and interlobular septal thickening, concerning for diffuse alveolar hemorrhage. Flexible bronchoscopy confirmed diffuse alveolar hemorrhage; microbiological analyses of bronchoalveolar washings did not reveal a causative organism. Mycoplasma pneumoniae-specific IgM in serum studies was consistent with mycoplasma pneumonia as the most likely etiology of this patient's diffuse alveolar hemorrhage and resultant hemoptysis. This report points to the need to consider atypical mycoplasma pneumonia as a possible etiology of hemoptysis in patients with underlying sarcoidosis.

Relapse of polymicrobial endocarditis in an intravenous drug user.

A 26-year-old male intravenous drug user (IDU) presented twice within 6 months with relapsed polymicrobial infective endocarditis (IE) due to Eikenella corrodens and Streptococcus constellatus after completing two courses of appropriate antimicrobial therapy. This report points to relapsing endocarditis as a clinical entity that warrants attention in IDUs when E. corrodens or S. constellatus are causative agents of IE.

TORC1 kinase and the S-phase cyclin Clb5 collaborate to promote mitotic spindle assembly and DNA replication in S. cerevisiae.

The Target of Rapamycin complex 1 (TORC1) is a central regulator of eukaryotic cell growth that is inhibited by the drug rapamycin. In the budding yeast Saccharomyces cerevisiae, translational defects associated with TORC1 inactivation inhibit cell cycle progression at an early stage in G1, but little is known about the possible roles for TORC1 later in the cell cycle. We investigated the rapamycin-hypersensitivity phenotype of cells lacking the S phase cyclin Clb5 (clb5Δ) as a basis for uncovering novel connections between TORC1 and the cell cycle regulatory machinery. Dosage suppression experiments suggested that the clb5Δ rapamycin hypersensitivity reflects a unique Clb5-associated cyclin-dependent kinase (CDK) function that cannot be performed by mitotic cyclins and that also involves motor proteins, particularly the kinesin-like protein Kip3. Synchronized cell experiments revealed rapamycin-induced defects in pre-anaphase spindle assembly and S phase progression that were more severe in clb5Δ than in wild-type cells but no apparent activation of Rad53-dependent checkpoint pathways. Some rapamycin-treated cells had aberrant spindle morphologies, but rapamycin did not cause gross defects in the microtubule cytoskeleton. We propose a model in which TORC1 and Clb5/CDK act coordinately to promote both spindle assembly via a pathway involving Kip3 and S phase progression.