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H Ayala

Publications and source records attributed to H Ayala.

10 recordsLinked to original sources

Massive hand crush: the role of a free muscle flap to obliterate the dead space and to clear deep infection.

Death of tissue and/or deep infection leading to amputation is not an uncommon course of events after massive crush injuries of the central part of the hand. Management of this injury faces the dual problem of having to carry out debridement in the central part of the hand which is radical enough to remove all dead tissue but which, in itself, creates a huge dead space in the depths of the wound. Inadequate debridement and/or leaving a dead space which fills with fluid and detritus behind the flexor tendons leads on to infection, devascularisation of the fingers and amputation. This paper presents the results of very radical debridement of the hand dorsal to the flexor tendons, including the intermetacarpal spaces, and filling the dead space with a well-vascularised free muscle flap in two hands which were referred in a pre-amputation stage, with one already being infected. Both hands were salvaged.

Accidents, Occupational↗

Differential induction of TNF-alpha and NOS2 by mitogen-activated protein kinase signaling pathways during Mycobacterium bovis infection.

The role of mitogen-activated protein kinase (MAPK) signaling pathways in the regulation of TNF-alpha and NOS2 production by human monocytes infected with Mycobacterium bovis BCG was examined. Inhibition studies showed that ERK1/2 and p38 MAPK activation were necessary for the monocyte response to M. bovis infection. Analysis of MAPK activation showed rapid phosphorylation of ERK1/2 and p38 in response to M. bovis BCG. Phosphorylation was not due to an autocrine effect of TNF-alpha secretion, since an anti-TNF-alpha antibody had no significant effect on the levels of p38 phosphorylation. The inhibitor PD98059 significantly reduced M. bovis BCG-induced TNF-alpha production and almost completely abrogated phosphorylation of ERK1/2; in addition the potent MEK inhibitor U0126 also abrogated phosphorylation. In contrast, studies using inhibitors selective for ERK1/2 and p38 showed that p38 plays an essential role in the induction of NOS2, whereas the role of ERK1/2 was minor. These results suggest that ERK1/2 and p38 kinases differentially regulate the M. bovis BCG-mediated induction of TNF-alpha and NOS2 in human monocytes.

Enzyme-Linked Immunosorbent Assay↗

Infection of human monocytes with Mycobacterium bovis BCG induces production of CC-chemokines.

DESIGN: CC-chemokines are potent leukocyte activators and chemoattractants, which have an important role in granuloma formation, function critical for the immune responses to mycobacterial infection. This study investigated whether infection of human monocytes with Mycobacterium bovis bacillus Calmette-Guérin (BCG) elicits secretion of RANTES, macrophage inflammatory protein (MIP)-1alpha and MIP-1beta. METHODS: RANTES, MIP-1alpha and MIP-1beta synthesis was measured by the presence of protein secretion in the cell culture supernatant as determined by enzyme-linked immunosorbent assay. To investigate the mechanism of M. bovis BCG stimulation of RANTES, we carried out inhibition assays with antibodies to CD40 and we used an intracellular calcium chelator BAPTA-AM. RESULTS: Infection of human monocytes with M. bovis BCG induced RANTES, MIP-1alpha and MIP-1beta secretion in a dose-dependent manner. This stimulation of CC-chemokines production was not attributed to LPS contamination. M. bovis-induced RANTES secretion was dependent upon bacterial uptake and on tumor necrosis factor (TNF)-alpha. Interestingly, the production of RANTES by M. bovis BCG-infected monocytes occurs through a mechanism that requires intracellular calcium and was significantly inhibited (P<0.05) with antibodies to CD40. CONCLUSIONS: These results suggest that the ability of M. bovis BCG to produce CC-chemokines might lead to protection in the acquired immune response of mycobacterial infection and at the same time indicate that M. bovis BCG-induced RANTES secretion is mediated by CD40 and dependent on the intracellular calcium influx.

Chemokine CCL3↗

Primary liposarcoma of bone: light and electron microscopic study.

The case history of a patient with primary liposarcoma of the humerus associated with a schwannoma of the radial nerve in the arm is described. Ultrastructurally, the neoplasm showed multiple and varied lipid droplets, dilated RER, mitochondria with electron-dense matrix, and microfilaments as the most prominent features. It is concluded, based on these ultrastructural observations, that liposarcoma of the bone is similar to pleomorphic liposarcoma arising in the soft tissues. This is the first ultrastructural study of a primary liposarcoma of the bone and the first reported association of this tumor with a schwannoma. The possible pathogenetic relationship between both tumors remains unknown.

Adult↗

Glomus tumor.

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Adult↗