Gas-phase clusters: spanning the States of matter

Gas-phase clusters, which are weakly bound aggregates comprised of either atoms or molecules, often display properties that lie between those of the gaseous and condensed states. Interesting questions arise concerning how large a cluster must be before it will display bulk properties. Currently there is extensive research activity directed toward studies of their formation and varying properties and reactivity as a function of the degree of aggregation. Results serve to elucidate at the molecular level the course of change of a system to be followed from the gas to the condensed state, thereby enabling a spanning of the states of matter.     

Pulmonary lesions induced by 3-methylindole and bovine respiratory syncytial virus in calves

Our objectives were to describe the ultrastructural morphogenesis of pulmonary lesions induced by 3-methylindole in 30- to 45-day-old Holstein calves and to determine whether toxic exposure to 3-methylindole exacerbates pulmonary lesions induced by bovine respiratory syncytial virus. Administration of 3-methylindole (0.25 g/kg) to calves resulted in interstitial edema and ultrastructural swelling of type-I alveolar epithelial cells and nonciliated bronchiolar epithelial cells as early as 4 to 6 hours after intraruminal administration. More severe alveolar edema containing protein was associated with swelling of capillary endothelial cells at 2 days after administration. Proliferation of type-II alveolar epithelial cells was first observed at 2 days after 3-methylindole administration, and marked hyperplasia of type-II epithelial cells and nonciliated bronchiolar epithelial cells was evident by 4 days after administration. Pulmonary cytochrome P-450 monooxygenase concentrations decreased significantly (P less than 0.001) by 12 hours after administration and did not increase significantly again by 8 days after administration. Calves were inoculated with bovine respiratory syncytial virus 3 days after administration of 3-methylindole, and pulmonary lesions were assessed 5 days after viral inoculation. Viral replication was demonstrated by fluorescence microscopy for viral antigen or by transmission electron microscopy in ciliated and nonciliated airway epithelial cells. Viral antigen was identified infrequently in alveolar macrophages and in type-II alveolar epithelial cells. 3-Methylindole exposure in calves did not result in more widespread distribution of viral antigen in alveolar tissue of respiratory syncytial virus-inoculated calves or in significant enhancement of viral pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)     

In vitro Sendai viral replication in pulmonary macrophages from mice treated with 4-ipomeanol

The ability of pulmonary macrophages from female mice given 4-ipomeanol (4-IP) to support viral replication in vitro was examined. On posttreatment days 5, 7, and 9, greater numbers of macrophages were recovered in lavage fluid from lungs of mice given 4-IP, compared with those from controls. Pulmonary macrophages recovered in lavage fluid from control mice and from mice given 4-IP supported Sendai virus replication in vitro, and nearly all Sendai virus produced in pulmonary macrophages from both groups was in an infectious form. On posttreatment days 5 and 7, slightly greater absolute numbers of virions were produced in pulmonary macrophages recovered from mice given 4-IP.     

Four multistate outbreaks of human Salmonella infections associated with live poultry contact, United States, 2009

Outbreaks of human salmonellosis associated with live poultry contact have been reported since 1955. Multiple Salmonella serotypes have been associated with these outbreaks, and specific outbreak strains have been repeatedly linked to single hatcheries over multiple years. During 2009, four multistate outbreaks of human Salmonella infections associated with direct and indirect exposure to live poultry purchased from mail-order hatcheries and agricultural feed stores were identified, resulting in 165 culture-confirmed cases in 30 states. This report describes the epidemiologic, environmental and laboratory investigations conducted by state and local health departments, state departments of agriculture, the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), National Poultry Improvement Plan (NPIP) and National Veterinary Services Laboratories (NVSL), and the Centers for Disease Control and Prevention (CDC). Case-patients were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance, and interviewed using the CDC standard live poultry contact questionnaire that asks about poultry-related exposures during the 7 days before illness onset. These outbreaks highlight the need to focus efforts on strategies to decrease and prevent human illness associated with live poultry contact through comprehensive interventions at the mail-order hatchery, agricultural feed store and consumer levels. Additional consumer education and interventions at mail-order hatcheries and venues where live poultry are sold, including agricultural feed stores, are necessary to prevent transmission of Salmonella from poultry to humans.     

Experimental bovine respiratory syncytial virus infection in conventional calves: ultrastructural respiratory lesions

The morphogenesis and repair of airway and alveolar injury induced by bovine respiratory syncytial virus (BRSV) was studied ultrastructurally in conventional calves to characterize pulmonary cell types susceptible to viral infection and cytopathologic changes associated with infection. Viral nucleocapsids and budding virions were present in tracheal and bronchial ciliated and nonciliated epithelial cells and mucous cells 3, 5, and 7 days after inoculation and in bronchiolar ciliated and nonciliated epithelial cells 5 days after inoculation. Mild interstitial pneumonia was observed 5 days after inoculation and was characterized by swelling of type 1 and type 2 alveolar epithelial cells, interstitial edema, and infiltration by lymphocytes and macrophages. Viral assembly and release in tracheal and bronchial epithelial cells was associated with loss of cilia from ciliated cells, formation of syncytial epithelial cells, swelling of mitochondria and endoplasmic reticulum, and cell necrosis. Neutrophils, lymphocytes, and macrophages were present in close association with the viral-infected and damaged epithelial cells. There was intercurrent hyperplasia of basal epithelial cells that, in association with other epithelial lesions, resulted in the loss of normal ciliated epithelium in these airways 5 and 7 days after inoculation. Regeneration of airway epithelium was largely completed by 10 days after inoculation, except in 1 of 4 calves that had failure of epithelial repair and that developed secondary bacterial pneumonia. Pulmonary ultrastructure in BRSV-inoculated calves 30 days after inoculation was indistinguishable from that in controls. The results demonstrated that BRSV can induce reversible alterations in airway epithelium, which may cause depression of mucociliary clearance and thereby enhance susceptibility to bacterial infection.     

Severe respiratory disease in dairy cattle in New York State associated with bovine respiratory syncytial virus infection

Severe respiratory disease associated with bovine respiratory syncytial virus (BRSV) infection has been identified in dairy cattle in New York State. The cases identified occurred in dairy calves and heifers. The disease was characterized in 4 animals by pathologic changes including interstitial pneumonia, necrotizing bronchiolitis with multinucleated syncytial epithelial cells and interstitial emphysema. BRSV antigen was demonstrated in lung samples or was isolated in tissue culture in all 4 cases. A retrospective survey of 6279 bovine diagnostic accessions between 1977 and 1982 revealed 66 cases of interstitial pneumonia, often with concurrent bronchiolitis. In this 5 year period, only 1 case in 1981 had interstitial pneumonia and bronchiolitis with pathologic features consistent with BRSV infection. It is concluded that pathogenic BRSV has entered New York State and that it is contributing to clinical respiratory disease in dairy cattle.     

Production of metallo-carbohedrenes in the solid state

Macroscopic quantities of the metallo-carbohedrenes TI(8)C(12) and V(8)C(12) have been synthesized with an arc discharge technique. Mass spectroscopy of raw soot samples generated in both an alternating and direct current arc between two metal-graphite powder composite electrodes establishes that the titanium and vanadium analogs of the metallo-carbohedrenes have been produced. An estimated yield of approximately 1 percent is obtained, and significantly, the products are stable in air.     

Acute and persistent alterations in pulmonary inflammatory cells and airway mast cells induced by Sendai virus infection in neonatal rats

Neonatal rats inoculated with parainfluenza type 1 (Sendai) virus develop alveolar dysplasia and bronchiolar hypoplasia by 30 to 110 days after inoculation. Weanling rats do not develop these abnormalities. Because neonatal animals have hyporesponsive immune and inflammatory cell functions, and because neonatal rats support pulmonary viral replication for longer duration and are delayed in their viral antibody response compared to weanling rats, we compared inflammatory and immune responses of two age groups of rats following viral inoculation. Data from quantitative bronchoalveolar lavage 1 to 29 days following viral inoculation demonstrated that neonates had significantly fewer (P less than 0.05) lymphocytes and macrophages in their bronchoalveolar fluid per cm2 alveolar surface than weanlings. Magnitude of neutrophil responses in neonatal rats compared to weanlings were not depressed. Pulmonary interferon activity was lower in neonates than in weanlings at 2, 3, 4, and 5 days after viral inoculation. Neonates failed to make antibody following intraperitoneal inoculation of inactivated viral antigen, whereas weanling rats had detectable viral antibody by 3 to 5 days after injection of antigen. At 90 days after inoculation of neonates, viral-inoculated rats had over 100-fold greater numbers (P less than 0.05) of mast cells in enzyme-dissociated lung preparations compared to age-matched controls. Viral-inoculated rats had two- to three-fold greater densities of mast cells (#/mm) in bronchiolar walls (P less than 0.02) than did control rats.(ABSTRACT TRUNCATED AT 250 WORDS)