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G Olmedo

Publications and source records attributed to G Olmedo.

At least 19 recordsLinked to original sources
PubMed1998

[Bronchiolitis obliterans with organizing pneumonia associated with idiopathic thrombocytopenic purpura].

We report a case of a 35 year-old woman with idiopathic thrombocytopenic purpura (ITP) who, under treatment with immunosuppressive drugs, developed bilateral interstitial pulmonary disease. Previously she had been splenectomized and treated with corticosteroids and cyclosporin. During the clinical course, the patient developed alterations of the hepatogram and presented a positive serology for Epstein-Barr virus. The lung biopsy showed the histologic pattern of obliterative bronchiolitis, interstitial inflammatory infiltration and intraalveolar pneumonia (BOOP). We could not find in the literature a previous report in which ITP was associated with BOOP. Of interest was the spontaneous remission of the pulmonary disease after suppression of cyclosporin and positive serology for Epstein-Barr virus.

Adult↗
PubMed1997

[Sarcomatoid carcinoma of the lung].

Sarcomatoid carcinomas of the lung are very uncommon tumors and their biological behavior remains controversial. Here we describe a case of a 62 year old male with an endobronchial mass and subjected thereafter to right upper and middle bilobectomy. A squamous carcinoma with a sarcomatous component resembling a fibrosarcoma was found at microscopic examination. Although there is neither agreement on the denomination nor on the histogenesis of these tumours, it is recognized that they are highly aggressive. Therefore, in order to provide the best possible treatment it appears recommendable to supply a detailed description of the different components of the tumor at the time of the histopathological diagnosis.

Carcinoma, Squamous Cell↗
PubMed1996

Structure and function of the Bacillus SpoIIE protein and its localization to sites of sporulation septum assembly.

Functioning of the spoIIE locus of Bacillus subtilis is required for formation of a normal polar septum during sporulation and for activation of the transcription factor sigma F, which directs early forespore-specific gene expression. We have determined the DNA sequence of the wild type and several mutant alleles of the spoIIE gene of B. subtilis and sequenced a substantial portion of its presumptive homologue in Bacillus megaterium. We show that the spoIIE locus encodes a single large protein with a predicted molecular mass of 92 kDa. Each of five point-mutation alleles, which have traditionally defined the locus, and two transposon-generated mutations were shown to fall within the coding sequence for the 92 kDa gene product or within sequences expected to be required for its expression. The amino-terminal portion of the predicted SpoIIE gene product, comprising approximately 40% of the protein, is extremely hydrophobic and is expected to contain up to 12 membrane-spanning segments. The remainder of the protein contains no hydrophobic segments long enough to span a lipid bilayer and is therefore presumed to comprise one or more globular, aqueous-phase exposed domains. An in-frame fusion joining the 3' end of the B. megaterium spoIIE coding sequence to the 5' end of gfp, a gene encoding the green fluorescent protein (GFP) of Aquorea victoria, resulted in a strong, sporulation-specific fluorescent signal localized to the sites of sporulation septum assembly. We speculate that SpoIIE plays a role in assembling the sporulation septum, perhaps determining the special properties of the structure that permit intercompartment signalling during development.

Alleles↗
PubMed1994

[Rounded atelectasis: another pulmonary pseudotumor].

Rounded atelectasis or Blesovsky's syndrome (also called pleuroma, folded lung or shrinking pleuritis with atelectasis) is the association of plaque-like pleural fibrosis with a folding visceral pleura and nodular atelectasis of the underlying lung. It can mimic a peripheral lung tumor or a mesothelioma. Radiography and computed tomography (CT) show a characteristic opacity with a comet-tail sign. The pathogenesis in some of the cases is considered to be secondary to pleural effusions and in others to a contraction of a focus of pleural fibrosis, not associated with effusion. In many cases, there was a history of asbestos exposure. We report the case of a 44-year-old, man who had smoked and worked with materials containing asbestos. He referred thoracic pain of 6 months duration and dyspnea. An X-ray of the chest (Fig. 1, 2) and a CT scan (Fig. 3) revealed a round peripheral mass in the left lower lobe. A fine needle aspiration biopsy of the lung was performed revealing clusters of large atypical cells with abundant cytoplasm. A thoracotomy was decided upon and no frozen section was requested. Gross examination of the resected lobe (Fig. 4) demonstrated a 2.5 cm white, irregular, firm and retracting pleural plaque. On sectioning, a peculiar folding of the visceral pleura delimited by anthracotic pigmentation was noted below the fibrotic plaque. The folding extended perpendicularly deep into the parenchyma. It was possible to separate the folding and liberate the underlying parenchyma, which was firm, fibrotic and atelectatic. No tumor was found anywhere within the lobe.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy, Needle↗
PubMed1990

Novel mutations that alter the regulation of sporulation in Bacillus subtilis. Evidence that phosphorylation of regulatory protein SpoOA controls the initiation of sporulation.

Sporulation in Bacillus subtilis is a complex developmental process that occurs in response to nutrient deprivation. To identify components of the mechanism that allows cells to monitor their nutritional status and to understand how this sensory information is transduced into a signal to activate specific sporulation genes, we have isolated mutants that are able to sporulate efficiently under nutritional conditions that strongly inhibit sporulation in wild-type bacteria, a phenotype we refer to as Coi (control of initiation). Four coi mutations were found to be within the coding sequence of spoOA, a gene in which null mutations prevent the initiation of sporulation and a gene whose product shares a domain of homology with phosphorylation-activated proteins that play signal transduction roles in bacteria. All four of the spoOA mutations were within this conserved domain and in close proximity to the presumptive phosphoacceptor site. The wild-type and one of the mutant SpoOA proteins were purified and shown to be competent to accept phosphoryl groups from a phosphohistidine within a bacterial signal transduction kinase (CheA). The mutant SpoOA protein exhibited enhanced phosphoacceptor activity compared with the wild-type. This property of the mutant protein, together with additional genetic information, supports a model for regulation of sporulation initiation by control of the phosphorylation level of SpoOA.

Alleles↗
PubMed1978

Acute miliary tuberculosis presenting as acute respiratory failure.

A 42 year old pregnant woman was admitted in acute respiratory failure. Viral pneumonia was suspected and oxygen therapy, CPAP, water restriction and diuretics were started with good response. She remained febrile and had an abnormal chest X-ray, a diagnosis of miliary tuberculosis was confirmed by transbronchial fibreoptic lung biopsy.

Acute Disease↗
PubMed1975

Idiopathic interstitial pulmonary fibrosis with hypercapnia.

A 38-year-old patient with effort dyspnea, somnolence, cianosis and cor pulmonale is presented. Chest roentgenograms and lung function studies suggested the diagnosis of pulmonary fibrosis. The patient showed also severe hypercapnia with normal resting ventilation and ventilatory response to exercise lower than usual for this condition. Autopsy confirmed the clinical diagnosis. This subject may belong to the growing group of patients where CO2 retention is not explained by their pulmonary pathology.

Adult↗
PubMedDate not supplied

A genetic analysis of Spo0A structure and function.

Mutations that enhanced sporulation in the presence of high concentrations of key nutrients (coi mutations) included at least four lesions within the phosphoacceptor domain of spo0A, a member of the response regulator family of "two-component" signal transduction proteins. The nature of these mutations and the phenotypes they produce support the model that the sporulation state of Spo0A controls the initiation of sporulation. This was further supported by the observation that site-directed mutations of acidic pocket aspartate residues expected to prevent phosphorylation also completely abolished sporulation. Using some of the acidic pocket aspartate substitution mutants as starting material, intragenic suppressors were isolated that restored efficient sporulation. Suppressors of D56Q mutations were deletions that removed all or part of the first alpha helix of the phosphoacceptor domain. Structural modelling of these deletions suggests a hypothesis to explain how phosphorylation of response regulator proteins may result in a conformational change that activates their effector functions.

Bacillus subtilis↗