Systematic Identification of MCU Modulators by Orthogonal Interspecies Chemical Screening.

The mitochondrial calcium uniporter complex is essential for calcium (Ca2+) uptake into mitochondria of all mammalian tissues, where it regulates bioenergetics, cell death, and Ca2+ signal transduction. Despite its involvement in several human diseases, we currently lack pharmacological agents for targeting uniporter activity. Here we introduce a high-throughput assay that selects for human MCU-specific small-molecule modulators in primary drug screens. Using isolated yeast mitochondria, reconstituted with human MCU, its essential regulator EMRE, and aequorin, and exploiting a D-lactate- and mannitol/sucrose-based bioenergetic shunt that greatly minimizes false-positive hits, we identify mitoxantrone out of more than 600 clinically approved drugs as a direct selective inhibitor of human MCU. We validate mitoxantrone in orthogonal mammalian cell-based assays, demonstrating that our screening approach is an effective and robust tool for MCU-specific drug discovery and, more generally, for the identification of compounds that target mitochondrial functions.

Pediatric primary follicular mucinosis: further evidence of its relationship with mycosis fungoides.

Follicular mucinosis (FM) is an uncommon reaction pattern in which the accumulation of mucin in the follicular epithelium is the main pathologic finding. FM may be idiopathic (primary follicular mucinosis [PFM]), in association with mycosis fungoides or cutaneous T-cell lymphoma, or in association with other neoplastic and inflammatory conditions. Herein we report a case of PFM with identical T-cell clone rearrangement at anatomically distinct sites, supporting the idea that some authors have proposed, that FM may represent a low-grade lymphoproliferative disease related to mycoses fungoides with favorable prognosis.

Síndrome de Stevens-Johnson/necrolisis epidérmica tóxica tratado con inmunoglobulinas intravenosas / Stevens-Johnson Syndrome/Toxic epidermal necrolysis treated with intravenous immunoglobulins

El síndrome de Stevens-Johnson (SSJ) y la necrolisis epidérmica tóxica (NET) se engloban dentro de un mismo espectro de enfermedad, pues sólo se diferencian por el grado de despegamiento cutáneo. En la NET se ve afectada más del 30 % de la superficie corporal, por lo que se convierte en un proceso grave cuya frecuencia se estima en 1,2-6 casos por millón de habitantes y año. Se describe a un varón de 75 años que sufrió un SSJ con evolución a NET, probablemente por la ingesta de extracto de ginkgo biloba. Fue tratado con inmunoglobulinas intravenosas, con dosis de 0,5 g/kg/día durante 5 días consecutivos, con evolución favorable y sin efectos secundarios relevantes. Es evidente que casos aislados no justifican el uso sistemático de este tratamiento, pero pueden contribuir a una mayor experiencia

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are part of the same disease spectrum, but are differentiated by the degree of skin detachment. In TEN, more than 30 % of the body's surface area is affected; thus, it is a serious process, whose frequency is estimated at 1.2-6 cases per million population/year. We describe the case of a 75-year-old male who suffered from SJS which evolved into TEN, probably because of the ingestion of ginkgo biloba extract. He was treated with intravenous immunoglobulins (Ig IV) at a dose of 0.5 g/kg/day for five consecutive days, with favorable progress and no significant side effects. It is evident that isolated cases do not justify the systematic use of this treatment, but they may help build up experience

Hipertricosis lanuginosa adquirida paraneoplásica / Acquired paraneoplastic hypertrichosis lanuginosa

La hipertricosis lanuginosa adquirida, un proceso paraneoplásico poco frecuente, consiste en el desarrollo rápido de pelo tipo lanugo, fundamentalmente en cara. Se describe una mujer de 50 años con hipertricosis en cara y porción superior del cuerpo de 4 meses de evolución y pérdida de peso en los últimos 6 meses, en la que se detectó la presencia de un carcinoma epidermoide de cuello uterino inoperable. La hipertricosis lanuginosa es un indicador de mal pronóstico. Se asocia a tumores de cualquier localización, pero con mayor frecuencia, pulmonares y colorrectales. Este caso es el primero asociado a carcinoma epidermoide de cuello uterino

Acquired hypertrichosis lanuginosa, an infrequent, paraneoplastic process, consists of the rapid development of lanugo-type hair, primarily on the face. We describe a 50-year-old woman with a 4-month case of hypertrichosis on the face and upper body, and weight loss over the last 6 months, in whom an inoperable squamous cell carcinoma of the cervix was discovered. Hypertrichosis lanuginosa is an indicator of a poor prognosis. It is associated with tumors in any location, but most often with lung and colorectal tumors. This is the first case associated with squamous cell carcinoma of the cervix

Regulation of NF-kappaB activation by protein phosphatase 2B and NO, via protein kinase A activity, in human monocytes.

It has been reported previously that a short synthetic immunomodulating peptide (Pa) and the neuropeptide beta-endorphin modulate the immune system. We have found now that NF-kappaB participates in the stimulation of monocytes by both peptides and we investigated the molecular mechanism by which these stimuli activate NF-kappaB. Pa and beta-endorphin induce accumulation of cyclic 3('),5(')-adenosine monophosphate (cAMP) in a calcium/calmodulin-dependent fashion since it was completely inhibited by the calmodulin antagonist W-7. The effect of these complexes seems to be mediated, at least in part, by nitric oxide (NO) synthesized by constitutive NO synthase since the NO synthase inhibitor N-methyl-L-arginine (NMLA) reduced the elevation of cAMP. Furthermore, the NO donor SIN-1 provoked nitration of G(S)alpha, leading to the cAMP elevation that was suppressed by the G(S)alpha-selective antagonist NF-449. Interestingly, the rapid degradation of NF-kappaB inhibitor IkappaBalpha induced by Pa- and beta-endorphin was reversed by a pretreatment with H-89 and cyclosporin A, inhibitors of protein kinase A (PKA) and protein phosphatase 2B (PP2B), respectively. These observations are consistent with the inhibition caused by W-7, NMLA, H-89, and cyclosporin A on NF-kappaB induction by these agonists, indicating the involvement of PKA and PP2B in the regulation of NF-kappaB in human monocytes.

Modifications in the C terminus of the synaptosome-associated protein of 25 kDa (SNAP-25) and in the complementary region of synaptobrevin affect the final steps of exocytosis.

Fusion proteins made of green fluorescent protein coupled to SNAP-25 or synaptobrevin were overexpressed in bovine chromaffin cells in order to study the role of critical protein domains in exocytosis. Point mutations in the C-terminal domain of SNAP-25 (K201E and L203E) produced a marked inhibition of secretion, whereas single (Q174K, Q53K) and double mutants (Q174K/Q53K) of amino acids from the so-called zero layer only produced a moderate alteration in secretion. The importance of the SNAP-25 C-terminal domain in exocytosis was also confirmed by the similar effect on secretion of mutations in analogous residues of synaptobrevin (A82D, L84E). The effects on the initial rate and magnitude of secretion correlated with the alteration of single vesicle fusion kinetics since the amperometric spikes from cells expressing SNAP-25 L203E and K201E and synaptobrevin A82D and L84E mutants had lower amplitudes and larger half-width values than the ones from controls, suggesting slower neurotransmitter release kinetics than that found in cells expressing the wild-type proteins or zero layer mutants of SNAP-25. We conclude that a small domain of the SNAP-25 C terminus and its counterpart in synaptobrevin play an essential role in the final membrane fusion step of exocytosis.