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Biomedical subjects

G G Pietra

Publications and source records attributed to G G Pietra.

At least 19 recordsLinked to original sources
PubMed2000

Peripheral papillary tumor of type-II pneumocytes: a rare neoplasm of undetermined malignant potential.

Peripheral papillary adenomas of the lung are uncommon neoplasms (only ten cases have been described so far in the English literature) composed predominantly of type-II pneumocytes and generally considered benign. We describe here two additional cases of this lung tumor. In both cases histological examination revealed an encapsulated papillary neoplasm with invasion of the capsule and, in one case, invasion of the adjacent alveoli and visceral pleura too. The proliferative index (Ki67) was less than 2% and the epithelial cells were positive for cytokeratins, surfactant apoproteins (SP), and nuclear thyroid transcription factor-1 (TTF- 1). Ultrastructurally, the epithelial cells showed the characteristic surface microvilli and cytoplasmic lamellar inclusions of type-II cells. Review of the literature has revealed two other cases of peripheral papillary adenoma of type-II pneumocytes with infiltrative features. Thus, we propose replacing the term peripheral papillary adenoma with peripheral papillary tumor of undetermined malignant potential.

Adenoma↗
PubMed2000

Immunotargeting of glucose oxidase to endothelium in vivo causes oxidative vascular injury in the lungs.

Vascular immunotargeting is a novel approach for site-selective drug delivery to endothelium. To validate the strategy, we conjugated glucose oxidase (GOX) via streptavidin with antibodies to the endothelial cell surface antigen platelet endothelial cell adhesion molecule (PECAM). Previous work documented that 1) anti-PECAM-streptavidin carrier accumulates in the lungs after intravenous injection in animals and 2) anti-PECAM-GOX binds to, enters, and kills endothelium via intracellular H(2)O(2) generation in cell culture. In the present work, we studied the targeting and effect of anti-PECAM-GOX in animals. Anti-PECAM-GOX, but not IgG-GOX, accumulated in the isolated rat lungs, produced H(2)O(2,) and caused endothelial injury manifested by a fourfold elevation of angiotensin-converting enzyme activity in the perfusate. In intact mice, anti-PECAM-GOX accumulated in the lungs (27 +/- 9 vs. 2.4 +/- 0.3% injected dose/g for IgG-GOX) and caused severe lung injury and 95% lethality within hours after intravenous injection. Endothelial disruption and blebbing, elevated lung wet-to-dry ratio, and interstitial and alveolar edema indicated that anti-PECAM-GOX damaged pulmonary endothelium. The vascular injury in the lungs was associated with positive immunostaining for iPF(2alpha)-III isoprostane, a marker for oxidative stress. In contrast, IgG-GOX caused a minor lung injury and little (5%) lethality. Anti-PECAM conjugated with inert proteins induced no death or lung injury. None of the conjugates caused major injury to other internal organs. These results indicate that an immunotargeting strategy can deliver an active enzyme to selected target cells in intact animals. Anti-PECAM-GOX provides a novel model of oxidative injury to the pulmonary endothelium in vivo.

Animals↗
PubMed1999

The expression of TIA-1+ cytolytic-type granules and other cytolytic lymphocyte-associated markers in CD30+ anaplastic large cell lymphomas (ALCL): correlation with morphology, immunophenotype, ultrastructure, and clinical features.

Anaplastic large cell lymphomas (ALCL) are a heterogeneous group of CD30+ large cell lymphomas; the most characteristic type have a T or null cell phenotype, often express epithelial membrane antigen (EMA) and cytolytic lymphocyte markers, and often possess a nonrandom t(2;5)(p23;q35) chromosomal translocation. We studied 22 (19 T, 1 null, 2 B cell) ALCL, including four primary cutaneous ALCL (PC-ALCL), for the expression of TIA-1, the cytotoxic T lymphocyte (CTL) or natural killer (NK) cell-associated antigens CD4, CD8, betaF1, TCRdelta1, CD56, and CD57, the ALCL-associated antigens p80 and EMA, and the Hodgkin's disease-associated marker CD15 to better define the relationship of these markers to histological subtype, primary site, and patient clinical characteristics. TIA-1 expression was seen in 12 of 20 (60%) T or null cell ALCLs with a cytoplasmic, granular distribution. Ultrastructural studies showed cytotoxic-type granules (dense core, multivesicular, and intermediate types) with TIA-1 localized to granules on immunogold labeling. TIA-1 staining strongly correlated with young patient age (< or = 32 years, P < .05) and EMA expression (P < .05). Excluding the four PC-ALCL cases, TIA-1 staining also correlated with p80 expression (P < .05) in all of the T cell cases. Three CD15+ cases were TIA-1-. TIA-1 expression in T or null cell ALCL was seen in all morphological subtypes (2 of 2 small cell variant, 3 of 4 monomorphic variant, and 7 of 14 pleomorphic variant) and primary tumor sites (6 of 14 nodal, 2 of 4 primary cutaneous, 2 of 2 bone, and 2 of 2 soft tissue). TIA-1+ granules were seen in all subsets: 5 of 6 CD4+, 1 of 2 CD8+, 4 of 8 CD56+, and 1 of 2 CD57+ ALCL. Of note, 4 of 10 T or null cell ALCL expressed gammadelta T-cell receptors (TCR), whereas only 1 of 10 T or null cell ALCL was alphabeta TCR+; TCR were not detected in five cases. TIA-1 was expressed by 3 of 4 gammadelta TCR+ ALCL and 1 of 1 alphabeta TCR+ ALCL. These data support a cytotoxic lymphocyte phenotype in most T or null cell ALCL and suggest that some T cell ALCL are derived from cytolytic CD4+ T cells, gammadelta T cells, or NK-like (CD56+ or CD57+) T cells.

Adolescent↗
PubMed1998

Desmin myopathy involving cardiac, skeletal, and vascular smooth muscle: report of a case with immunoelectron microscopy.

Desmin myopathy is a rare idiopathic disorder characterized by abnormal aggregates of desmin-type intermediate filaments, which affects cardiac and skeletal muscle, and rarely the intestinal smooth muscle. We report a 42-year-old woman with atrial fibrillation and progressive restrictive cardiomyopathy. Left ventricular biopsy, cardiac explant, and subsequent autopsy study of skeletal muscle revealed cytoplasmic granulo-filamentous inclusions that were continuous with Z-lines and were immunoreactive for desmin filaments both at the light immunohistochemical and electron microscopic level. In addition, we report the presence of characteristic inclusions within the smooth muscle of intramural coronary blood vessels. This is the first description of desmin inclusions within vascular smooth muscle, and underscores the systemic nature of this rare myopathy.

Adult↗
PubMed1998

Factor V Leiden is not common in patients diagnosed with primary pulmonary hypertension.

Substantial evidence suggests that thrombosis contributes to the pathogenesis of primary pulmonary hypertension (PPH). An abnormal factor V (factor V Leiden) may contribute to thrombosis in the pulmonary microcirculation of PPH patients. A point mutation in which adenine is substituted for guanine at nucleotide 1691 (1691A) alters factor V so that it resists cleavage by activated protein C. Heterozygosity for the 1691A mutation is more common (2-8%) in Caucasian Europeans and Americans than in Africans (1%) and Asians (<1%). The aim of the study was to examine the prevalence of the mutation that codes for factor V Leiden in individuals with PPH. We identified 42 Caucasians diagnosed with PPH. We extracted deoxyribonucleic acid (DNA) from whole blood and assayed DNA samples for the point mutation (1691 A) that codes for factor V Leiden. One out of 42 (2.4%; 95% confidence interval=0.1-12.6) Caucasians diagnosed with PPH was heterozygous for the normal 1691G and mutant 1691A allele. All 10 individuals with familial PPH were homozygous for the normal 1691G allele. The prevalence of heterozygosity for the 1691A allele and the normal 1691G allele does not differ from that observed in reference (control) populations. The low prevalence of the 1691A mutation among individuals diagnosed with primary pulmonary hypertension provides evidence that factor V Leiden does not contribute to the pathogenesis of the disease in most patients.

Adult↗
PubMed1996

Analysis of Epstein-Barr virus-associated posttransplantation lymphoproliferative disorder after lung transplantation.

BACKGROUND: Epstein-Barr virus (EBV)-associated posttransplantation lymphoproliferative disorder (PTLD) is a serious complication of lung transplantation. Besides immunosuppression the risk factors for PTLD development are largely unknown. METHODS: The incidence of PTLD was ascertained in a lung transplant population consisting of 45 patients. Nine patients (20%) experienced PTLD. The clinical, histologic, and human leukocyte antigen (HLA) data were collected on all patients. The incidence of EBV infection in lymphoid tissue taken at the time of engraftment was studied by using EBV in situ hybridization. RESULTS: All patients with PTLD had polymorphous lymphoproliferations, seven of which were polymorphous B-cell hyperplasias and two of which were polymorphous B-cell lymphomas. EBV was identified in all lesions. All patients with polymorphous B-cell hyperplasias had clinically unsuspected disease, five of which were identified at autopsy. The two polymorphous B-cell lymphoma lesions were monoclonal and regressed with immunosuppression reduction. EBV in situ hybridization on donor or recipient lymph nodes obtained at engraftment from the 45 transplant recipients showed no difference in the number of EBV positive cells in patients with and without PTLD. Cyclosporine and PTLD and azathioprine dosages and cyclosporine levels were similar between patients with and without PTLD. PTLD was seen in patients with high cumulative doses of antilymphocyte globulin. Analysis of HLA status showed a predominance of HLA A2 and DR7 in the donors of the patients with PTLD, whereas donor HLA B7 was more common in patients without PTLD> CONCLUSIONS: Detailed studies are necessary to further elucidate the risk factors for PTLD development in the lung transplant population.

Adult↗
PubMed1996

Lepidic intrapulmonary growth of malignant mesothelioma presenting as recurrent hydropneumothorax.

We report a case of malignant mesothelioma with unusual clinical and histological findings. The patient presented with recurrent hydropneumothorax and minimal pleural thickening on chest computed tomography (CT). Histologically, the pleura was involved by the malignant mesothelioma, albeit to a limited degree. Unexpectedly, the lung parenchyma from two different lobes showed focal nests of mesothelioma cells filling the alveolar spaces and growing on the luminal surface of the alveolar septa, closely resembling the multicentric growth pattern of bronchioloalveolar adenocarcinoma. Immunohistochemical and ultrastructural studies confirmed that the pulmonary lesions were an extension of the malignant mesothelioma. This case illustrates clinically, the importance of a high index of suspicion for malignancy in older patients with unexplained recurrent hydropneumothorax; and histologically the potential of malignant mesothelioma to invade the lung at an early stage of growth.

Aged↗
PubMed1996

Confocal- and electron-microscopic localization of FITC-albumin in H2O2-induced pulmonary edema.

Fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA) was used to detect sites of protein leakage in rat lungs perfused for 15-60 min with H2O2 (75, 150, and 300 microM). Leaky vessels were localized by confocal laser microscopy. Endothelial routes of protein leakage were identified by electron microscopy after photo-conversion of FITC-BSA to an osmiophilic diaminobenzidine product. Transport of FITC-BSA into the alveolar interstitium was assessed by immunogold labeling and anti-FITC antibodies. We detected leakage of FITC-BSA through transendothelial gaps in the pulmonary arterial endothelium after 30 min of perfusion with 300 microM H2O2 and after 60 min of perfusion with 150 microM H2O2. Junctional permeability and distribution of ZO-1 protein in the arterial endothelium were unchanged. Microvascular permeability to FITC-BSA was not increased in lungs perfused with H2O2. In lungs perfused with 300 microM H2O2, progressive extravasation of albumin was associated with significant increases in water content and perfusing pressure. We conclude that the pulmonary arterial endothelium is the primary target of circulating H2O2.

Animals↗
PubMed1995

Primary pulmonary hypertension and the human immunodeficiency virus. Report of two cases and a review of the literature.

We report two cases of human immunodeficiency virus (HIV) seropositivity and pulmonary hypertension seen at our institution and present a comprehensive literature review and available histopathologic findings of the association between HIV seropositivity and pulmonary hypertension. Studies and reviews pertaining to HIV seropositivity and pulmonary hypertension were identified through a MEDLINE search and reference citations. All studies and series found in the MEDLINE search were reviewed and are discussed in this article. Where data were available, comparisons and analyses were made between groups of reported cases of HIV seropositivity and pulmonary hypertension with regard to the following parameters: sex distribution, mode of acquiring HIV infection, presence or absence of the acquired immunodeficiency syndrome, CD4 cell counts, PO2 or oxygen saturation by pulse oximetry, concurrent lower respiratory tract infection, and histopathologic features. We conclude that there is strong evidence for pulmonary hypertension associated with HIV infection that is histologically indistinguishable from primary pulmonary hypertension. Consequently, HIV-seropositive patients with unexplained dyspnea should be evaluated for primary pulmonary hypertension. Prospective studies in HIV-positive patients are indicated.

Adult↗
PubMed1995

Neonatal adenovirus infection: a case report with in situ hybridization confirmation of ascending intrauterine infection.

Adenovirus infection is a rare, but serious infection, during the neonatal period. The actual model of infection at birth is currently unknown, however, several mechanisms have been proposed. We describe a case of fatal neonatal adenovirus pneumonia in a 25-wk gestational age infant. Adenovirus was confirmed by electron microscopy and by in situ hybridization. The maternal cervical/endocervical smear taken prior to the delivery contained epithelial cells with changes suggestive of adenovirus, which was confirmed by in situ hybridization on the smear. These findings suggest that ascending viral infection is a factor in the pathogenesis of neonatal adenovirus infection. The identification and reporting of adenovirus may be important during pregnancy in order to avoid delay in delivery of the fetus once membranes have ruptured.

Adenoviridae↗
PubMed1993

Liver abnormalities associated with chronic mercury accumulation in stranded Atlantic bottlenose dolphins.

Eighteen stranded Atlantic bottlenose dolphins (Tursiops truncatus) examined postmortem were sampled for histologic study. All cases were examined for ferric ion and lipofuscin. Ages were determined from tooth growth layers. Electron microscopic (EM) examination and X-ray spectroscopy (EDAX) were performed. Chemical analysis for mercury was conducted on 12 of the animals by atomic absorption spectrophotometry. Nine animals were found to have excessive lipofuscin in both liver and kidney. Four of these nine animals also exhibited active liver disease (fat globules, central necrosis, lymphocytic infiltrates) whereas, of the animals without the excessive pigment, only one animal had an active liver lesion. EM and EDAX showed electron-dense amorphous material presumably within lysosomes to be Hg with no deposits on mitochondrial or nuclear membranes noted. Age relationship to portal pigment deposition was positive. Liver mercury concentrations ranged from 0.01 to 443 micrograms/g of wet weight with all animals having liver pigment yielding values of or above 61 micrograms/g, whereas all animals lacking pigment had values of or below 50 micrograms/g. The evidence suggests that the excessive pigment accumulation is related to toxic effects of Hg and presents as increased active liver disease.

Age Factors↗
PubMed1993

Primary aortoduodenal fistula: a unique presentation of a pseudoaneurysm associated with cystic medial necrosis.

A 42-yr-old man who exsanguinated from an acute upper gastrointestinal bleed was found to have a primary aortoduodenal fistula on postmortem examination. The fistula arose in an aortic pseudoaneurysm associated with cystic medial necrosis. Although there was no suggestion of Marfan's syndrome on physical examination, there was cystic medial necrosis of not only the involved aorta, but also other systemic arteries. Primary aortoduodenal fistula is a rare cause of acute upper gastrointestinal bleeding and is usually associated with atherosclerotic disease of the aorta. This is the first report of a pseudoaneurysm associated with cystic medial necrosis presenting as an aortoduodenal fistula.

Adult↗
PubMed1992

Primary pulmonary hypertension in association with human immunodeficiency virus infection. A possible viral etiology for some forms of hypertensive pulmonary arteriopathy.

Recent reports have suggested a possible association between HIV-1 infection and primary pulmonary hypertension (PPH), but most of the patients described to date have either had acquired immunodeficiency syndrome (AIDS) with concurrent lung infections or have administered Factor VIII intravenously for hemophilia. We report three human immunodeficiency virus type 1 (HIV-1)-positive homosexual white males with clinical and hemodynamic diagnoses of PPH. None of the patients had any opportunistic lung infections or other pulmonary pathology, nor were they hemophiliacs. They had no histories of intravenous drug use. Lung tissue from two of the patients revealed hypertensive arteriopathy consistent with PPH and no other pulmonary pathology. Attempts at localizing HIV-1 infection to the vascular endothelium with electron microscopy, immunohistochemistry, DNA in situ hybridization, and polymerase chain reaction techniques did not reveal direct pulmonary artery infection with the virus. These data and the finding of tubuloreticular structures on electron microscopy suggest that HIV-1 may play a role in the pathogenesis of these cases of PPH through mediator release associated with HIV-1 infection rather than by direct endothelial infection.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Interstitial pneumonitis, pulmonary fibrosis, and chronic graft-versus-host disease.

Pneumonopathies in association with graft-versus-host disease (GVHD) are known, but the evolution of biopsy-proven interstitial pneumonitis (IP) to pulmonary fibrosis as a major pulmonary manifestation in an individual patient with chronic GVHD has not been previously reported. We present a patient with chronic GVHD who developed IP and then pulmonary fibrosis. We suggest that IP with evolution to pulmonary fibrosis was a major pulmonary manifestation of chronic GVHD in this patient.

Adolescent↗
PubMed1991

Pseudomesotheliomatous carcinoma of the lung. An immunohistochemical and ultrastructural study of three cases.

The authors report immunohistochemical and electron microscopic studies on three new cases of pseudomesotheliomatous carcinoma of the lung. Although the distinct clinical and histopathologic features of this peripheral lung cancer were described many years ago, its recognition as a distinct variety of lung carcinoma has not gained wide acceptance. Little is known of its incidence and only few cases have been reported until now. In the current study the authors demonstrate the epithelial nature of this tumor by its positive immunohistochemical reactions for epithelial membrane antigen (EMA), carcinoembryonic antigen (CEA), Leu-M1, B 72.3, and surfactant apoprotein. The ultrastructural features and staining of nuclear inclusions with surfactant apoprotein indicate differentiation into type II cells as found in other forms of peripheral lung adenocarcinoma. Despite these morphologic similarities, pseudomesotheliomatous carcinoma is characterized by extensive invasion of the pleura and rapidly fatal course. Because of this biologic behavior it deserves recognition as a distinct variant of peripheral lung carcinoma.

Adenocarcinoma↗