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Biomedical subjects

H I Pass

Publications and source records attributed to H I Pass.

At least 91 records · Page 5Linked to original sources
PubMed1994

Isolated lung perfusion with tumor necrosis factor: a swine model in preparation of human trials.

Isolated lung perfusion with tumor necrosis factor (TNF) potentially could deliver high doses of drug and avoid systemic toxicity in patients with unresectable lung cancer or metastases. We investigated the feasibility of isolated lung perfusion with TNF in a pig model. Eleven animals had left-sided isolated lung perfusion with no TNF (n = 3), 40 micrograms/kg TNF (n = 2), 80 micrograms/kg TNF (n = 3), and 40 micrograms/kg TNF at moderate (39.5 degrees C) hyperthermia (n = 3). Hemodynamic monitoring and measurement of systemic and pulmonary circuit TNF levels were performed. Surviving animals were electively sacrificed a minimum of 6 months after isolated lung perfusion. All sham-perfused pigs survived. Isolated lung perfusion elevated pulmonary artery pressure, decreased cardiac output, and had minimal effects on mean pressure (15 +/- 0 versus 32 +/- 8 mm Hg, 4.5 +/- 1.1 versus 3.03 +/- 0.03 L/min, 67 +/- 11 versus 61 +/- 2 mm Hg; before versus after 90 minutes of isolated lung perfusion). Both 40 micrograms/kg animals and 2 of the 3 hyperthermic perfusion pigs survived, with 1 requiring pneumonectomy. Of the three 80 micrograms/kg animals, 1 survived, 1 died, and 1 required pneumonectomy. Survivors, compared with dying animals, had lower systemic/pulmonary TNF ratios and lower peak systemic TNF levels. All surviving pigs were electively sacrificed. These data justify phase I human protocols of isolated lung perfusion with TNF and hyperthermia; however, intraoperative leak rates must be monitored to ensure pulmonary isolation because systemic TNF levels may dictate treatment morbidity/mortality.

Animals↗
PubMed1994

A method to facilitate subxiphoid pericardiotomy.

Pericardial effusion can be treated effectively by the technique of subxiphoid pericardial window. We present a case in which the Cooper retractor designed for transcervical thymectomy facilitated this operation. When available, the Cooper retractor can be useful in selected patients.

Adenocarcinoma↗
PubMed1994

Thoracotomy for pulmonary mycoses in non-HIV-immunosuppressed patients.

Pulmonary mycoses can be life threatening in patients who are in an immunocompromised state stemming from defective host defenses or the use of certain treatment regimens. In 36 immunosuppressed patients undergoing thoracotomy for the treatment of pulmonary fungal disease, the underlying cause of immunosuppression was malignancy (n = 9), Wegener's granulomatosis (n = 4), hematologic disorders (aplastic anemia, 5-Q minus syndrome, or myelofibrosis) (n = 6), or chronic granulomatous disease of childhood (n = 17). The mean age of the patients was 25 years, and 89% were symptomatic (fever, n = 27; cough, n = 20; chest pain, n = 14; and other, n = 13). Chest x-ray studies revealed the presence of cavitary disease (n = 7), a mass (n = 8), infiltrates (n = 20), or cavity and infiltrate (n = 1). A preoperative diagnosis was lacking in 23 of the 36 patients. Procedures included wedge biopsy (n = 13), segmentectomy with or without wedge or chest wall resection (n = 5), lobectomy with or without chest wall resection (n = 16), wedge resection plus completion pneumonectomy (n = 1), and segmentectomy plus completion pneumonectomy (n = 1). Fungi identified included Aspergillus (n = 23), Zygomycetes (n = 4), Cryptococcus (n = 3), and other (n = 6; 1 each), and specific antifungal treatment was instituted in 34 of the patients (94%). The 31% operative (ie, < 30-day or inhospital) mortality was chiefly due to multiorgan system failure (9/11).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Surgical pathology of the lung in chronic granulomatous disease.

The pathologic features in pulmonary specimens are reported from 32 open thoracotomies of 20 patients with chronic granulomatous disease (CGD). The pattern of inflammation present in the resected material varied, but a granulomatous component was present in each case. In 78% of the specimens, a distinctive form of granuloma was found: a neutrophilic microabscess surrounded by palisading histiocytes. In four specimens eosinophils were also found within the microabscesses. This feature was found exclusively in cases of fungal infection. Fungal organisms were found by culture in 18 specimens (56%) and in 17 of these specimens (94%), they also were seen by histopathology. In 9 cases (28%) routine bacterial cultures were positive, and in one case an atypical Mycobacterium was cultured. These organisms were not prospectively identified on special stains of histologic sections in any of the cases. Abscess formation was found more commonly in pure fungal infections (41%) than in pure bacterial infections (14%). In contrast to earlier reports, well-formed granulomas with giant cells were not specific for fungal infections. In this series, they were present in 57% of cases with pure bacterial infections. A subset of the patients received gamma interferon therapy or granulocyte transfusions before the surgical procedures. No differences in the histopathology of the inflammation were associated with granulocyte transfusions, but gamma interferon therapy was associated with a reduction in necrotizing granulomatous inflammation. Additionally, one case of severe cytomegalovirus pneumonitis is described in a CGD patient receiving chronic steroid therapy.

Adolescent↗
PubMed1994

Invasive zygomycosis due to Conidiobolus incongruus.

During the past decade, an increasing spectrum of pathogenic Zygomycetes fungi have caused infections in humans. The preponderance of these deeply invasive infections have been caused by members of the order Mucorales. However, deeply invasive zygomycoses due to genera of the order Entomophthorales (Conidiobolus species and Basidiobolus species) have seldom been reported. We describe a granulocytopenic patient with pulmonary and pericardial zygomycosis due to Conidiobolus incongruus, describe this organism's susceptibility to antifungal agents, characterize its diagnostic microbiological characteristics, and review previously reported cases of deeply invasive zygomycosis due to Conidiobolus species. In immunocompromised patients, C. incongruus is an uncommon but highly invasive fungal pathogen that may be resistant to amphotericin B and can be distinguished from other Zygomycetes fungi by characteristic mycological features.

Adult↗
PubMed1994

Intrapericardial pheochromocytoma complicated by massive intraoperative hemorrhage.

Middle mediastinal pheochromocytomas are exceedingly rare. Because so few cases have been reported, consensus has not been reached regarding the anesthetic management of patients with these tumors. The use of cardiopulmonary bypass (CPB) for the resection of intrapericardial pheochromocytomas has met with varied success. We report the first documented case of successful anesthetic and surgical management of an acute, massive hemorrhage during the dissection of an intrapericardial pheochromocytoma, which was managed without cardiopulmonary bypass. Perioperative anesthetic considerations, including the risks and benefits of CPB, are discussed.

Acute Disease↗
PubMed1994

A comparison of the standard high dose dexamethasone suppression test and the overnight 8-mg dexamethasone suppression test for the differential diagnosis of adrenocorticotropin-dependent Cushing's syndrome.

To improve the overnight 8-mg dexamethasone (DEX) suppression test (DST) for differential diagnosis of Cushing's syndrome and to develop optimal criteria for its interpretation, we increased the number of blood samples and measured the suppression of both plasma ACTH and cortisol. Forty-one patients who were subsequently proven at surgery to have Cushing's syndrome were studied (34 Cushing's disease and 7 ectopic ACTH secretion). DEX (8 mg, orally) was administered at 2300 h. Blood samples for ACTH and cortisol measurements were obtained at 0800, 0830, and 0900 h on the day before and at 0700, 0800, 0900, and 1000 h on the morning after DEX treatment. The conventional 6-day DST was also performed, with measurement of both urinary free cortisol and urinary 17-hydroxysteroids as indices of suppression. Optimal criteria for the diagnosis of Cushing's disease were developed for both the overnight 8-mg and the 6-day tests using receiver operating characteristic curves. The results were compared with those using the previously published criteria for diagnosis of Cushing's disease by the overnight 8-mg test (> 50% suppression of plasma cortisol at 0700-0800 h). In our patients, the previously published criterion for the overnight 8-mg test yielded high sensitivity (88%), but low specificity (57%), in making the diagnosis of Cushing's disease. When the time of cortisol measurement and the diagnostic criteria for Cushing's disease were revised to achieve 100% specificity, the sensitivity of the overnight 8-mg test was 71%, which was not significantly different from that of the 6-day test (79%; P = NS). Addition of plasma ACTH levels to the test did not improve diagnostic accuracy compared to that with measurement of plasma cortisol levels alone. When the revised 8-mg overnight dexamethasone suppression test was combined with the 6-day dexamethasone suppression test, sensitivity increased to 91%, with a specificity of 100%, which was significantly better than that of the overnight 8-mg test alone (P < 0.002). We conclude that the overnight 8-mg DST has low specificity for the diagnosis of Cushing's disease when performed as originally described. However, with revised sampling times and diagnostic criteria, the overnight test has sensitivity and specificity similar to those of the conventional 6-day DST. The diagnostic performance of a criterion that combines the results of both tests is better than the diagnostic performance of either test alone.

Administration, Oral↗
PubMed1994

Contemporary approaches in the investigation and treatment of malignant pleural mesothelioma.

The cellular and molecular biology of mesothelioma is a complicated, multifactorial, incompletely understood process of carcinogenesis. Normal mesothelial cells can be transformed into a malignant phenotype by multiple factors, usually asbestos. Several tumor suppressor genes may be lost, and several oncogenes can be activated. A local environment of inflammation with associated release of cytokines may promote deregulated cell growth. The release of immunosuppressive substances such as nitric oxide may contribute to this process. The interaction of asbestos and viral DNA incorporation is unclear but warrants further investigation. In the majority of mesothelioma patients, present standard therapies have little effect on survival. Clinical trials studying a variety of innovative treatment strategies are being performed at centers with a significant referral base for the disease. Future treatments, however, must be based on understanding of the biology of mesothelioma.

Asbestos↗
PubMed1994

Postoperative complications in patients receiving suramin therapy.

BACKGROUND: Suramin is an antiparasitic agent that is currently being evaluated for antineoplastic activity. Documented toxicities of suramin include adrenal and renal insufficiency, coagulation factor abnormalities, immunosuppression, and polyneuropathy. These adverse effects have potential for contributing to postoperative morbidity in surgical patients. Because no experience with suramin has been reported in the surgical literature, this 5-year retrospective review of postoperative complications in patients receiving suramin was performed. METHODS: From a review of 171 charts, 14 patients were identified who had undergone a major surgical procedure either while receiving intravenous suramin or within 1 year after its administration. Primary diagnoses included prostate cancer (six), lymphoma (four), ovarian cancer (two), colon cancer (one), and glioblastoma (one). All patients received replacement dose hydrocortisone at the initiation of suramin therapy and thereafter. RESULTS: Eighteen major surgical procedures were performed with 18 complications occurring in five patients. The predominant complications encountered were hemorrhage (five), impaired wound healing (three), and bowel dysmotility (two). A highly significant relationship existed between the incidence of complications and interval from completion of suramin therapy to the time of operation (p < 0.0005), with 17 of the 18 morbidities occurring within the first month. The length of operation (p < 0.05) and amount of blood transfused during the procedure were related to postoperative morbidity (p < 0.05). No other factors evaluated were correlated to complications. CONCLUSIONS: This experience suggests the avoidance of elective procedures during the first month after suramin therapy and a heightened awareness of the potential for bleeding and wound healing problems in patients receiving suramin who do require an emergent procedure.

Adult↗
PubMed1994

Simian virus 40-like DNA sequences in human pleural mesothelioma.

Mesotheliomas are pleural, pericardial, or peritoneal neoplasms frequently associated with asbestos exposure, and it is estimated that over the next twenty years up to 80,000 new cases are expected in the USA alone. We found simian virus 40-like DNA sequences in 29 of 48 mesotheliomas studied (60%) and demonstrated simian virus large-T antigen expression in 13 of 16 specimens. The matching lung samples did not contain simian virus 40-like sequences; however, they contained asbestos. These findings are to our knowledge the first demonstration of a physical link between DNA virus-like sequences and human mesothelioma. We suggest that a simian virus 40-like virus may act independently or as a co-carcinogen with asbestos. Moreover, the selective large T antigen expression by mesothelioma and not by the surrounding pulmonary parenchyma may have both diagnostic and therapeutic implications.

Adult↗
PubMed1994

Tumor necrosis factor induces doxorubicin resistance to lung cancer cells in vitro.

Tumor necrosis factor can alter the cell cycle of tumor cells and protect hematopoietic stem cells from cell cycle-specific chemotherapy, but the ability of tumor necrosis factor to protect cancer cells from chemotherapy by manipulation of the cell cycle is unknown. Twenty-four-hour exposure of A549 human lung cancer cells to tumor necrosis factor shifted cells from S phase to G0/G1 phase as determined by analysis of isolated cell nuclei with an FACScan Cell Sorter. This effect was not seen in cells exposed to interleukin-1 or interleukin-6. Growth assays demonstrated that tumor necrosis factor slowed the doubling time of A549 cells, confirming that tumor necrosis factor caused G0/G1 arrest in these cells. Pretreatment with tumor necrosis factor rendered cells resistant to subsequent 1-hour exposure to doxorubicin, a chemotherapeutic agent active against S phase cells. Tumor necrosis factor did not protect cells against either cisplatin or mitomycin C, drugs not specific for S phase. Measurement of intracellular drug levels indicated that pretreatment with tumor necrosis factor did not affect doxorubicin uptake or efflux. These findings suggest that cells producing tumor necrosis factor within a tumor may render surrounding malignant cells resistant to cell cycle-specific chemotherapy, and this mechanism may explain failure of sequential immunotherapy-chemotherapy protocols.

Adenocarcinoma↗
PubMed1993

Individualized chemotherapy for patients with non-small cell lung cancer determined by prospective identification of neuroendocrine markers and in vitro drug sensitivity testing.

We attempted to prospectively select individualized chemotherapy for 165 non-small cell lung cancer patients based on in vitro analysis of neuroendocrine (NE) markers and drug sensitivity testing (DST) using fresh tumor. The chemotherapy used for small cell lung cancer (SCLC) was selected when NE marker expression determined by L-dopa decarboxylase assay was documented. Selection of chemotherapy for other patients was guided by DST results using a modified dye exclusion assay when available; otherwise etoposide and cisplatin was administered. A total of 112 of 165 (68%) specimens were assayed for L-dopa decarboxylase and 36 patients (22%) had DST. In vitro data directed management for 27 of 96 (28%) patients given chemotherapy: 6 with NE markers were treated with the SCLC regimen; and 21 (58% of those with DST) received their DST-selected chemotherapy regimen. There were no significant differences in response rate among all 3 treatment arms (P = 0.076). However, response to chemotherapy for the patients treated prospectively with a SCLC regimen was 3 of 6 (50%), marginally better than patients given their DST-selected chemotherapy regimen (2 of 21; 9%; P = 0.056) or those treated with etoposide and cisplatin (10 of 69; 14%; P = 0.061). When patients whose NE markers were identified retrospectively are included, 4 of 9 (44%) responded to administered chemotherapy, compared to 7 of 55 (13%) with no NE markers present (P = 0.04). There were no differences in survival among the three treatment groups. Cisplatin and etoposide comprised the most active regimen in vitro for tumors from 16 of 36 (44%) patients, potentially limiting the benefit of DST since this is often the empiric therapy for non-SCLC. Furthermore, the correlation between in vitro and clinical response is nonsignificant for all drugs tested, highlighting the overall relative resistance of non-SCLC tumors to currently available chemotherapy.

Antineoplastic Agents↗
PubMed1993

Photodynamic therapy in oncology: mechanisms and clinical use.

In photodynamic therapy (PDT), a sensitizer, light, and oxygen are used to cause photochemically induced cell death. The mechanism of cytotoxicity involves generation of singlet oxygen and other free radicals when the light-excited sensitizer loses or accepts an electron. Although selective retention of sensitizer by malignant tissue is seen in vivo, the mechanisms for this sensitizer targeting remain unclear. The first-generation sensitizers are porphyrin based and vary in lipophilicity and hydrophilicity. Targeting of the vasculature seems to be a prominent feature of the cytotoxic effect of these sensitizers in vivo, with resulting necrosis. Treatment depth varies with the wavelength of light that activates the sensitizer used, and the second-generation sensitizers are activated at longer wavelengths, allowing for a 30% increase in treatment depths. The selectivity of targeting can be increased when the sensitizer is delivered with the use of liposomes or monoclonal antibodies specific for tumor antigens. Studies have demonstrated direct effects of PDT on immune effector cells, specifically those with lineage from macrophages or other monocytes. Clinically, this therapy has been chiefly used for palliation of endobronchial and esophageal obstruction, as well as for treatment of bladder carcinomas, skin malignancies, and brain tumors. The future of PDT rests in defining its use either as an intraoperative adjuvant to marginal surgical procedures or as a primary treatment for superficial malignancies. Phase III trials in esophageal cancer and lung cancer are in progress and will help in evaluation of whether Photofrin II, the most widely used sensitizer, can be added to the oncologic armamentarium, pending approval from the U.S. Food and Drug Administration.

Dihematoporphyrin Ether↗
PubMed1993

Surgical management of pulmonary infections in chronic granulomatous disease of childhood.

Chronic granulomatous disease of childhood is an inheritable disorder of phagocytic cell respiratory burst resulting in recurrent, life-threatening, catalase-positive infections. The lung is the most common site of infection, and pulmonary disease is the primary cause of death in greater than 50% of children with chronic granulomatous disease. Still, the role of surgery in management of this disease remains undefined. Between 1974 and 1990, 19 patients with chronic granulomatous disease required 31 thoracic interventions at our institution. Patients ranged in age from 2.5 to 27 years (mean age, 15 years). Seventeen of 19 patients (89%) had had previous pulmonary infections. Patients presented as toxic (temperature > 38.5 degrees C, chest pain, and cough) in 22 instances before the 31 procedures. Aggressive surgical intervention for diagnosis and extirpation of localized infections was undertaken with lobectomy/pneumonectomy with or without other procedures (5), bisegmentectomy (2), segmentectomy with or without other procedures (5), or wedge with or without other procedures (13). In five instances, an empyema was drained; a chest tube for a sterile collection was placed in one instance. There was one intraoperative death, and 3 patients died 22 to 600 days postoperatively with overwhelming sepsis. The mean hospitalization was 101 days (range, 24 to 600 days). Wound complications occurred in 5 patients, requiring 17 separate anesthetic debridements. A change in therapy was dictated by the results of the procedure in 23 of 31 instances (74%). Thoracic surgeons must be aware of this rare cause of immunosuppression in these children and, due to the unusual nature of the pulmonary infections, should follow an aggressive approach in their diagnosis and management.

Adolescent↗