Hemidiaphragmatic paralysis: a rare complication of cervical herpes zoster

Herpes zoster, a sequel of the reactivation of the varicella zoster virus, usually presents with cutaneous eruptions associated with intense pain and burning sensation in the affected dermatomes. Motor weakness, however, can sometimes complicate herpes zoster. In this report we present a case that had diaphragmatic motor weakness as a sequel of herpes zoster lesions in the neck.

Paroxysmal Nocturnal Hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hemolytic disorder of acquired origin and is clinically manifested by chronic hemolysis, thromboses in various sites, and bone marrow failure. The disease isso rare that the delay in the diagnosis is not uncommon and this bears a tremendous impact on patientmanagement. We present this case to draw attention to this uncommon cause of hemolytic anemia, whichshould be considered in any patient, of any age, who has signs of chronic hemolysis.Key Words: Paroxysmal Nocturnal Hemoglobinuria, Hemolytic anemia.

Paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare hemolytic disorder of acquired origin and is clinically manifested by chronic hemolysis, thromboses in various sites, and bone marrow failure. The disease is so rare that the delay in the diagnosis is not uncommon and this bears a tremendous impact on patient management. We present this case to draw attention to this uncommon cause of hemolytic anemia, which should be considered in any patient, of any age, who has signs of chronic hemolysis.

Caspase-dependent deubiquitination of monoubiquitinated nucleosomal histone H2A induced by diverse apoptogenic stimuli

Enzymatic deubiquitination of mono-ubiquitinated nucleosomal histone H2A (uH2A) and H2B (uH2B) is closely associated with mitotic chromatin condensation, although the function of this histone modification in cell division remains ambiguous. Here we show that rapid and extensive deubiquitination of nucleosomal uH2A occurs in Jurkat cells undergoing apoptosis initiated by anti-Fas activating antibody, staurosporine, etoposide, doxorubicin and the proteasome inhibitor, N-acetyl-leucyl-leucyl-norlucinal. These diverse apoptosis inducers also promoted the accumulation of slowly migrating, high molecular weight ubiquitinated proteins and depleted the cellular pool of unconjugated ubiquitin. In apoptotic cells, ubiquitin was cleaved from uH2A subsequent to the appearance of plasma membrane blebbing, and deubiquitination of uH2A closely coincided with the onset of nuclear pyknosis and chromatin condensation. Nucleosomal uH2A deubiquitination, poly (ADP-ribose)polymerase (PARP) cleavage and chromatin condensation were prevented in cells challenged with apoptosis inducers by pretreatment with the pan-caspase inhibitor, zVAD-fmk, or by over-expressing anti-apoptotic Bcl-xL protein. These results implicate a connection between caspase cascade activation and nucleosomal uH2A deubiquitination. Transient transfection of 293 cells with the gene encoding Ubp-M, a human deubiquitinating enzyme, promoted uH2A deubiquitination, while an inactive mutated Ubp-M enzyme did not. However, Ubp-M-promoted deubiquitination of uH2A was insufficient to initiate apoptosis in these cells. We conclude that uH2A deubiquitination is a down-stream consequence of procaspase activation and that unscheduled cleavage of ubiquitin from uH2A is a consistent feature of the execution phase of apoptosis rather than a determining or initiating apoptogenic event. Nucleosomal uH2A deubiquitination may function as a cellular sensor of stress in situations like apoptosis through which cells attempt to preserve genomic integrity.