Patterns and significance of exhaled-breath biomarkers in lung transplant recipients with acute allograft rejection.

BACKGROUND: Obliterative bronchiolitis (OB) remains one of the leading causes of death in lung transplant recipients after 2 years, and acute rejection (AR) of lung allograft is a major risk factor for OB. Treatment of AR may reduce the incidence of OB, although diagnosis of AR often requires bronchoscopic lung biopsy. In this study, we evaluated the utility of exhaled-breath biomarkers for the non-invasive diagnosis of AR. METHODS: We obtained breath samples from 44 consecutive lung transplant recipients who attended ambulatory follow-up visits for the Johns Hopkins Lung Transplant Program. Bronchoscopy within 7 days of their breath samples showed histopathology in 21 of these patients, and we included them in our analysis. We measured hydrocarbon markers of pro-oxidant events (ethane and 1-pentane), isoprene, acetone, and sulfur-containing compounds (hydrogen sulfide and carbonyl sulfide) in exhaled breath and compared their levels to the lung histopathology, graded as stable (non-rejection) or AR. None of the study subjects were diagnosed with OB or infection at the time of the clinical bronchoscopy. RESULTS: We found no significant difference in exhaled levels of hydrocarbons, acetone, or hydrogen sulfide between the stable and AR groups. However, we did find significant increase in exhaled carbonyl sulfide (COS) levels in AR subjects compared with stable subjects. We also observed a trend in 7 of 8 patients who had serial sets of breath and histopathology data that supported a role for COS as a breath biomarker of AR. CONCLUSIONS: This study demonstrated elevations in exhaled COS levels in subjects with AR compared with stable subjects, suggesting a diagnostic role for this non-invasive biomarker. Further exploration of breath analysis in lung transplant recipients is warranted to complement fiberoptic bronchoscopy and obviate the need for this procedure in some patients.

Tropisetrón en la prevención de náuseas y vómitos por quimioterapia: estudio clínico multicéntrico / Tropisetron in the prevention of nausea and vomiting due to chemotherapy: multicentric clinical study

The antiemetic effect of tropisetron was studied in 97 cancer patients (67 men, 30 women) receiving cisplatin in doses of 75 mg/m² or higher. On 279 chemotherapy cycles studied (max 6 per patient) 5 mg of tropisetron was admonistered once a day i.v. on day 1 and p.o. on day 2 to 6. Efficacy preventing vomiting and nausea was measured in 24 hour period as: complete control 0 episodes, major control 1 to 2 episodes, minor control 3 to 4 episodes and no control 5 or more episodes. Satisfactory vomiting control (complete and major) was 69 percent, 63 percent, 82 percent,88 percent, 96 percent and 96 percent in days 1 to 6 of cycle 1. Satisfactory nausea control (complete and major) for the same day was 70, 66, 72, 85 92 and 97 percent. Similar data was obtained for the subsequeny cycles. Complete vomiting control was obtained in 47, 35, 56, 72, 81 and 84 percent and for nausea in 42, 39, 48, 64, 81 and 87 percent. 19 patients presented adverse effects (19,6 percent). Only 2 headache episodes had a definitive relation with antiemetic drug. 12 patients discontinued the medication; 6 due to drug inefficacy, 2 to illness unrelated to the drug, 1 to lack of collaboration, and 3 due to other reasons. We conclude that tropisetron allows satisfactory control of acute and delayed vomiting in a high percentage of patients treated with high doses of cisplatin. The drug does not have significant secondary effects. Tropisetron administration in only 1 daily dose implies an evident advantage and a treatment cost reduction

Formaldehyde levels in air and wet precipitation at Mexico City, Mexico.

Formaldehyde concentrations in ambient air and in rain water were measured at the University of Mexico, Mexico City. Air samples were taken twice a day, from 9:00 to 13:00 h and from 13:00 to 16:00 h local time from July to December 1985. Rain water was collected on daily bases from July to October, i.e. during the rainy season. The ambient air mean value was 24.4 x 10(-3) ppmv for morning hours, while the afternoon mean value was 18.5 x 10(-3) ppmv. The formaldehyde concentration in wet precipitation ranged from 0.10 to 0.80 mg liter(-1) (3.3 to 26.6 micromoles liter(-1)) 0.41 mg liter(-1) (13.7 microoles liter(-1)). A comparison of the results of this study with some measurements made at remote maritime sites, rural and urban areas, indicated that the formaldehyde levels in the atmosphere and rain water of Mexico City are among the highest reported in the literature, including the data reported by Grosjean (1982) for Los Angeles, California, during severe photochemical pollution conditions.

Respuesta de los trabajadores a los microorganismos suspendidos en la atmósfera de una fábrica de papel / Response of workers to airbone microorganisms at a paper manufacturing plant

Se realizó una investigación sobre la respuesta inmunológica de los trabajadores de una fábrica de papel. Un grupo de 44 trabajadores expuestos a microorganismos presentes en el aire de la fabrica provenientes del bagazo de la caña enmohecido constituyó el grupo expuesto y 23 individuos que laboran en un hospital integraron el grupo testigo. Se registró un alto grado de contaminación tanto por microorganismos como por material particulado en la atmósfera del cuarto de molienda (25.168 hon os/m3 y 27.8 mg/m3 respectivamente). Al analizar el bagazo y las muestras de aire fue posible aislar diferentes actinomicetos y hongos incluyendo a Thermoactinomyces vulgaris un actinomiceto, que puede producir Alveolitis Alérgica. Las reacciones inmunológicas de los trabajadores señalan la presencia de anticuerpos contra la mayoría de los antígenos de los microorganismos aislados, pero solamente un individuo con bagazosis presento una respuesta positiva contra T. Vulgaris

Amoebae isolated from the atmosphere of Mexico City and environs.

A protozoological analysis was performed from June to August, 1982 to isolate small free-living amoebae from the atmosphere by using an air vacuum sampler and several filters. Monoxenic medium (nonnutritive agar plus Escherichia coli) and axenic medium (De Jonckheere, 1977) were used to culture the isolates. The species isolated included Naegleria sp. Alexeieff emend. Calkins, Acanthamoeba polyphaga Puschkarew, Vahlkampfia jugosa Page, Acanthamoeba astronyxis Ray and Hayes, Acanthamoeba castellanii Douglas, Acanthamoeba culbertsoni Singh y Das, Vahlkampfia ustiana Page, Saccamoeba stagnicola Page, Hyalodiscus sp. Hertwig and Lesser, Platyamoeba placida Page, Rugipes sp. Schaeffer, Vannella platypodia Gläser, Vahlkampfia russelli Singh, Vahlkampfia ovis Schmidt, and Leptomyxa flabellata Goodey. Among the species isolated Naegleria sp., A. polyphaga, A. culbertsoni, and A. castellanii include strains, known to be pathogenic in humans.

Pathogenic and free-living protozoa cultured from the nasopharyngeal and oral regions of dental patients: II.

Protozoa of the nose, mouth, and pharynx of 30 randomly chosen male caries patients at an odontological clinic of the National Autonomous University of Mexico, in Mexico City, were surveyed by culture from swabs. Culture tubes from swabs were observed every other day for 5 weeks. Pathogens found included Entamoeba histolytica, Naegleria fowleri, Acanthamoeba castellanii, A. culbertsoni, A. polyphaga, and Giardia lamblia. Such isolations of pathogens suggest that patients may be healthy carriers of cysts and trophic forms of protozoa responsible for several human diseases. Amoebae responsible for primary amoebic meningoencephalitis were well represented in the samples. Small pathogenic free-living amoebae have not been isolated before from healthy males in Mexico. Many species of free-living cyst-forming protozoa and some commensals without cysts were also cultured from swabs.

Cytogenetic effects of cadmium accumulation on water hyacinth (Eichhornia crassipes).

Cadmium was bioassayed to observe cytogenetic effects in the water hyacinth (Eichhornia crassipes). Plants were exposed for 96 hr to freshwater containing 0.01, 0.05, 0.10, 1.5, and 10 mg/liter of cadmium. Metal concentrations in tissues were determined by atomic absorption spectrophotometry. The highest level was found in roots, thus root-tip cells were used for cytogenetic studies; after 24 hr of exposure, micronuclei, c-mitotic effects, and pycnosis were detected and after 48 hr polyploidy was observed. A linear relationship between frequencies of micronuclei and cadmium concentrations was found: at 1.5, and 10 mg/liter micronuclei numbers were always the lowest. The inhibition of cell proliferation. shown by the low mitotic index, was proportional to the concentration and time of exposure. From the results presented in this paper it may be concluded that water hyacinth is a good sensor, due to its fast rate of metal accumulation, which allows an easy way to determine the presence of potential mutagenic compounds in water.