PubMed Health⌕ Search

Biomedical subjects

F M Morales

Publications and source records attributed to F M Morales.

5 recordsLinked to original sources

Specific twin junctions in doped zirconia.

The effect of different dopant cations on the phase transformations of the initially stabilized supersaturated tetragonal ZrO(2) phase during various heat treatments has been studied. The obtained fraction of monoclinic grains develop twinned structures, but there is still a lack of information about the character of grain boundaries formed in doped monoclinic solid solutions. The inspection of particular selected-area electron diffraction patterns provides an alternative method with respect to high-resolution electron microscopy or electron back-scattered diffraction for characterizing different twin junctions in various doped zirconia systems. The classification of these special twins is based on the coincidence site lattice concept.

Journal Article↗

Evasion mechanisms to tumor necrosis factor alpha (TNF-alpha) of small cell lung carcinoma and non-small cell lung carcinoma cell lines: comparison with the erythroleukaemia K-562 cell line.

The tumour necrosis factor alpha (TNF-alpha) is produced by mononuclear phagocytes as a defence mechanism against malignant cells. However, these cells can evade destruction by TNF-alpha. The present study evaluates in three lung cancer cell lines (small cell carcinoma NCI-H69, adenocarcinoma A-427, squamous carcinoma SK-MES-1) and one erythroleukaemia (K-562) cell line the following evasion mechanisms: (1) inhibition of TNF-alpha production, in indirect and direct co-cultures with monocytes; (2) the expression of type I and type II receptors for TNF-alpha (TNFRI and TNFRII) by tumour cell lines, using indirect immunofluorescence and flow cytometry; (3) the sensitivity of tumour cell lines to the toxic action of recombinant human TNF-alpha (rhTNF-alpha). With the exception of cell line NCI-H69, the other tumour cell lines liberated soluble factors that inhibited TNF-alpha production in monocytes. This effect occurred even after membrane contact with the A-427 and SK-MES-1 cell lines. Erythroleukaemia K-562 cells expressed both types of receptors for TNF-alpha, whereas the NCI-H69 cells expressed only TNFRI, and the A-427 and SK-MES-1 cells expressed no receptors. Lines NCI-H69, A-427 and K-562 were insensitive to the cytotoxic action of rhTNF-alpha. In conclusion, different lung cancer cell lines may evade destruction by TNF-alpha by various mechanisms that range from blocking TNF-alpha production by monocytes to blocking the cytotoxic action of this molecule. For selecting the most effective immunotherapy, knowledge of the evasion mechanisms would be useful.

Adenocarcinoma↗

Diagnosis of parenchymal Hodgkin's disease using bronchoalveolar lavage.

The usefulness of bronchoalveolar lavage in the diagnosis of parenchymal Hodgkin's disease is illustrated in this case report. Recovery of characteristic Reed-Sternberg cells from the lavage fluid may serve as both a diagnostic and staging procedure and potentially may obviate more invasive steps such as thoracotomy.

Adult↗

Microprocessor exercise physiology systems vs a nonautomated system. A comparison of data output.

Several microprocessor exercise physiology systems have been introduced recently. Comparison of the data output between these systems and more traditional nonautomated systems has not been reported extensively. Twelve normal adult men were exercised in random sequence on different days on a Sensormedics MMC Horizon system, the Medical Graphics Corporation System 2000, and a nonautomated system. heart rate, minute ventilation, tidal volume, respiratory frequency, oxygen consumption, and carbon dioxide production were compared at each level of work during a maximal incremental test and during a constant work load test. The overall data output between the three systems was comparable. However, minute ventilation was consistently higher on the Medical Graphics system, oxygen consumption was consistently lower on the Horizon system, and a technical error was discovered in the Medical Graphics system which resulted in a systematic overestimation of carbon dioxide production. Different methods of analyzing the data from the same test (60-s average, 15-s average, breath-by-breath, and 8-breath average) resulted in differences of up to 20 percent in the maximal values. This was greater than the differences between the three systems. Despite the comparability of the data output, important differences did exist which can be potentially significant when data output from one system are compared to predicted normal values obtained under different conditions.

Adult↗