RESUMEN
Nanomaterials (NMs) are now gaining popularity to be used in agriculture as fertilisers to reduce the dose of conventional fertilisers and enhance nutrient use efficiency. Urea has found its application as a conventional nitrogenous fertiliser since long, however, the nutrient use efficiency of the bulk form of urea is low due to issues related to ammonia volatilisation. This study proposes a biogenic synthesis route to develop urea nanoparticles that can be used as nano-fertiliser for better uptake and hence improved nutrient efficiency. Large scale production and widespread application of these nano-fertilisers to the agricultural fields will enhance the direct exposure to workers and farmers. Therefore, the occupational safety evaluation becomes critical. In this study, we report a new method for synthesis of urea nanoparticles (TNU, absolute size: 12.14 ± 7.79 nm) followed by nano-safety evaluation. Herein, the pulmonary and ocular compatibilities of TNU were investigated in vitro and in vivo respectively. The assay for cellular mitochondrial activity was carried out on human lung fibroblasts (WI-38) under varied TNU exposure concentrations up to 72 h. The acute biocompatibility effect, ocular irritation and sub-lethal effects were measured on New Zealand Rabbit. The results show that TNU do not exhibit any cytotoxicity and detrimental cell mitochondrial activity up to the highest tested concentration of 1000 µg/mL and 72 h of testing. The animal experiment results also show that neither acute nor sub-lethal toxic effects can be detected after TNU ocular instillation up to 21 days when tested up to environmentally relevant concentration of 15 µg/mL. These results suggest the occupational safety of biogenic urea nanoparticles and support its application as nanofertiliser.
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One of the major toxic effects of exposure to ammonia is the resulting pulmonary acute and chronic effects. This study investigated the acute pulmonary effects of exposure to ammonia lower than the recommended threshold limit value (TLV). This cross-sectional study was conducted in 2021 in four chemical fertilizer production industries using ammonia as the main raw material. A total of 116 workers who were exposed to ammonia were investigated. The level of exposure to ammonia was measured by NMAM 6016, and the evaluation of pulmonary symptoms and function parameters was done using the American Thoracic Society and European Respiratory Society protocols in four sessions. The paired-sample t-test, repeated measures test, Chi-square, and Fisher's exact test were run to analyze the collected data. The prevalence rates of pulmonary symptoms, including cough, dyspnea, phlegm, and wheezing, were 24.14, 17.24, 14.66, and 16.38%, respectively, after one exposure shift. It was observed that all pulmonary function parameters were reduced after one exposure shift to ammonia. The results revealed that the parameters of vital capacity, forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), the FEV1/FVC ratio, and peak expiratory flow significantly decreased (p < 0.05) across four exposure shifts. The findings indicated that exposure to ammonia at concentrations lower than one-fifth of TLV could bring about acute pulmonary effects and reduce pulmonary function parameters, similar to the pattern observed in obstructive pulmonary diseases.
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Amoníaco , Exposición Profesional , Humanos , Amoníaco/toxicidad , Amoníaco/análisis , Valores Limites del Umbral , Estudios Transversales , Pulmón/química , Tos/epidemiología , Tos/etiología , Volumen Espiratorio Forzado , Capacidad Vital , Exposición Profesional/efectos adversosRESUMEN
BACKGROUND: Over one-third of the U.S. population is exposed to unsafe levels of ozone (O3). Dietary supplementation with fish oil (FO) or olive oil (OO) has shown protection against other air pollutants. This study evaluates potential cardiopulmonary benefits of FO or OO supplementation against acute O3 exposure in young healthy adults. METHODS: Forty-three participants (26 ± 4 years old; 47% female) were randomized to receive 3 g/day of FO, 3 g/day OO, or no supplementation (CTL) for 4 weeks prior to undergoing 2-hour exposures to filtered air and 300 ppb O3 with intermittent exercise on two consecutive days. Outcome measurements included spirometry, sputum neutrophil percentage, blood markers of inflammation, tissue injury and coagulation, vascular function, and heart rate variability. The effects of dietary supplementation and O3 on these outcomes were evaluated with linear mixed-effect models. RESULTS: Compared with filtered air, O3 exposure decreased FVC, FEV1, and FEV1/FVC immediately post exposure regardless of supplementation status. Relative to that in the CTL group, the lung function response to O3 exposure in the FO group was blunted, as evidenced by O3-induced decreases in FEV1 (Normalized CTL -0.40 ± 0.34 L, Normalized FO -0.21 ± 0.27 L) and FEV1/FVC (Normalized CTL -4.67 ± 5.0 %, Normalized FO -1.4 ± 3.18 %) values that were on average 48% and 70% smaller, respectively. Inflammatory responses measured in the sputum immediately post O3 exposure were not different among the three supplementation groups. Systolic blood pressure elevations 20-h post O3 exposure were blunted by OO supplementation. CONCLUSION: FO supplementation appears to offer protective effects against lung function decrements caused by acute O3 exposure in healthy adults.
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Contaminantes Atmosféricos , Ozono , Contaminantes Atmosféricos/farmacología , Femenino , Aceites de Pescado/farmacología , Humanos , Pulmón , Masculino , Ozono/efectos adversos , Pruebas de Función RespiratoriaRESUMEN
Bronchopulmonary dysplasia (BPD) is the most significant respiratory complication of prematurity, and its consequences last from birth into adulthood. Unfortunately, the dramatic improvements in the management of premature infants have not led to a decreased incidence of BPD, or to breakthroughs in treatments offered for this long-lasting chronic respiratory disorder. Over recent decades the pathological picture of BPD has changed from inflammation, interstitial fibrosis and emphysema attributed to volu-, barotrauma and oxygen toxicity to larger, simplified alveoli and dysmorphic vessels related to arrested alveolarization and vasculogenesis with inflammation maintaining a central role. Corticosteroids (CSs) play a key role in the development of respiratory epithelial cells and lung maturation. These potent anti-inflammatory agents have long been used for the prevention and treatment of BPD; however, the risk/benefit ratio of their use remains unresolved. CSs administered antenatally have contributed to reduce mortality and respiratory distress syndrome, no such effect on BPD reduction has been observed. Postnatal systemic CSs reduced the rate and severity of BPD, yet their long-term neurodevelopmental and respiratory consequences markedly limit routine administration. This is the first in a two-part State-of-the-Art series that reviews the latest relevant clinical trials investigating the short-term and long-term effects of CSs in the prevention and treatment of BPD.
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Displasia Broncopulmonar , Enfermedades del Prematuro , Corticoesteroides/uso terapéutico , Adulto , Displasia Broncopulmonar/tratamiento farmacológico , Displasia Broncopulmonar/etiología , Displasia Broncopulmonar/prevención & control , Dexametasona/uso terapéutico , Glucocorticoides/uso terapéutico , Humanos , Lactante , Recién Nacido , Enfermedades del Prematuro/tratamiento farmacológico , Inflamación/tratamiento farmacológicoRESUMEN
This paper is the second in a two-part State-of-the-Art series that reviews the latest relevant clinical trials investigating the short-term and long-term effects of corticosteroids in the prevention and treatment of bronchopulmonary dysplasia (BPD). Inhaled postnatal corticosteroids demonstrate low systemic bioavailability and rapid systemic clearance with high pulmonary deposition and were expected to reduce the incidence of BPD with reduced adverse effects, however, increased rate of mortality in the neonatal period and at the 18-24 months follow-up was observed. In a milestone study, intratracheal instillation of corticosteroids combined with surfactant decreased the incidence of BPD without increasing the mortality or the long-term neurodevelopmental adverse outcomes. However, subsequent trials using different types of surfactants, different surfactant to budesonide ratio, different time of the drug administration for infants with different severity of respiratory distress syndrome could not reproduce all the beneficial effects. Future perspectives for the identification of premature infants at high risk of BPD and the prevention or treatment of established BPD are discussed.
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Displasia Broncopulmonar , Surfactantes Pulmonares , Síndrome de Dificultad Respiratoria del Recién Nacido , Fármacos del Sistema Respiratorio , Administración por Inhalación , Corticoesteroides/uso terapéutico , Displasia Broncopulmonar/tratamiento farmacológico , Displasia Broncopulmonar/etiología , Displasia Broncopulmonar/prevención & control , Glucocorticoides/uso terapéutico , Humanos , Lactante , Recién Nacido , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Fármacos del Sistema Respiratorio/uso terapéutico , TensoactivosRESUMEN
Exposure to wildfire smoke continues to be a growing threat to public health, yet the chemical components in wildfire smoke that primarily drive toxicity and associated disease are largely unknown. This study utilized a suite of computational approaches to identify groups of chemicals induced by variable biomass burn conditions that were associated with biological responses in the mouse lung, including pulmonary immune response and injury markers. Smoke condensate samples were collected and characterized, resulting in chemical distribution information for 86 constituents across ten different exposures. Mixtures-relevant statistical methods included (i) a chemical clustering and data-reduction method, weighted chemical co-expression network analysis (WCCNA), (ii) a quantile g-computation approach to address the joint effect of multiple chemicals in different groupings, and (iii) a correlation analysis to compare mixtures modeling results against individual chemical relationships. Seven chemical groups were identified using WCCNA based on co-occurrence showing both positive and negative relationships with biological responses. A group containing methoxyphenols (e.g., coniferyl aldehyde, eugenol, guaiacol, and vanillin) displayed highly significant, negative relationships with several biological responses, including cytokines and lung injury markers. This group was further shown through quantile g-computation methods to associate with reduced biological responses. Specifically, mixtures modeling based on all chemicals excluding those in the methoxyphenol group demonstrated more significant, positive relationships with several biological responses; whereas mixtures modeling based on just those in the methoxyphenol group demonstrated significant negative relationships with several biological responses, suggesting potential protective effects. Mixtures-based analyses also identified other groups consisting of inorganic elements and ionic constituents showing positive relationships with several biological responses, including markers of inflammation. Many of the effects identified through mixtures modeling in this analysis were not captured through individual chemical analyses. Together, this study demonstrates the utility of mixtures-based approaches to identify potential drivers and inhibitors of toxicity relevant to wildfire exposures.
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Humo , Incendios Forestales , Animales , Análisis por Conglomerados , Ratones , Humo/efectos adversosRESUMEN
Foil Smoking/Heroin Inhalation Abstract. Foil smoking is generally heroin consumption by inhalation. By heating an aluminum foil with a fire lighter the heroin on top of the foil starts melting and the smoke is then inhaled using a straw. Foil smoking is the second most common form of heroin consumption after the intravenous use. In contrast to the IV administration, heroin inhalation effects are delayed by a few minutes and the risk of transmission of HIV, Hepatitis or other infectious diseases is not relevant. Severe bronchospasms can occur in patients with or without prior pulmonary disease such as asthma bronchiale. One cerebral consequence of foil smoking is leukoencephalopathy, a spongiform degeneration of the white matter. This is likely triggered by the pyrolysate generated during the heating process. Multiple drug use and concomitant cigarette smoking in heroin addicts make cause-effect relationships difficult to assess. In general, the history of inhalative heroin consumption should be considered in patients presenting with any unkown pulmonary disease with severe bronchospasms as may happen in a severe asthma exacerbation.
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Heroína , Narcóticos , Fumar , Administración por Inhalación , Heroína/administración & dosificación , Humanos , Narcóticos/administración & dosificaciónRESUMEN
Acid sphingomyelinase deficiency in type B Niemann-Pick disease leads to lysosomal sphingomyelin storage, principally affecting lungs, liver, and spleen. Infused recombinant enzyme is beneficial, yet its delivery to the lungs is limited and requires higher dosing than liver and spleen, leading to potentially adverse reactions. Previous studies showed increased enzyme pulmonary uptake by nanocarriers targeted to ICAM-1, a protein overexpressed during inflammation. Here, using polystyrene and poly(lactic-co-glycolic acid) nanocarriers, we optimized lung delivery by varying enzyme dose and nanocarrier concentration, verified endocytosis and lysosomal trafficking in vivo, and evaluated delivered activity and effects. Raising the enzyme load of nanocarriers progressively increased absolute enzyme delivery to all lung, liver, and spleen, over the naked enzyme. Varying nanocarrier concentration inversely impacted lung versus liver and spleen uptake. Mouse intravital and postmortem examination verified endocytosis, transcytosis, and lysosomal trafficking using nanocarriers. Compared to naked enzyme, nanocarriers increased enzyme activity in organs and reduced lung sphingomyelin storage and macrophage infiltration. Although old mice with advanced disease showed reactivity (pulmonary leukocyte infiltration) to injections, including buffer without carriers, antibody, or enzyme, younger mice with mild disease did not. We conclude that anti-ICAM nanocarriers may result in effective lung enzyme therapy using low enzyme doses.
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Anticuerpos Monoclonales/química , Portadores de Fármacos , Molécula 1 de Adhesión Intercelular/metabolismo , Nanopartículas/química , Enfermedad de Niemann-Pick Tipo B/terapia , Esfingomielina Fosfodiesterasa/farmacología , Animales , Anticuerpos Monoclonales/metabolismo , Transporte Biológico , Composición de Medicamentos , Endocitosis , Humanos , Molécula 1 de Adhesión Intercelular/genética , Ácido Láctico/química , Ácido Láctico/metabolismo , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/patología , Pulmón/efectos de los fármacos , Pulmón/enzimología , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Terapia Molecular Dirigida , Nanopartículas/administración & dosificación , Enfermedad de Niemann-Pick Tipo B/enzimología , Enfermedad de Niemann-Pick Tipo B/genética , Enfermedad de Niemann-Pick Tipo B/patología , Ácido Poliglicólico/química , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Poliestirenos/química , Poliestirenos/metabolismo , Esfingomielina Fosfodiesterasa/química , Esfingomielina Fosfodiesterasa/deficiencia , Esfingomielinas/metabolismo , Bazo/efectos de los fármacos , Bazo/enzimología , Bazo/patologíaRESUMEN
Acute changes in select physiological parameters associated with cardiovascular physiology (systolic and diastolic blood pressure (BP) and heart rate (HR)), pulmonary function (FVC, FEV1, and exhaled CO and NO) and adverse events were measured in 105 clinically confined subjects who were randomized into groups that either completely or partially switched from conventional cigarettes to e-cigarettes or completely discontinued using tobacco and nicotine products altogether. Use of the e-cigarettes for five days under the various study conditions did not lead to higher BP or HR values, negative respiratory health outcomes or serious adverse health events. Reductions in BP and HR vital signs were observed in most of the participants that either ceased tobacco and nicotine products use altogether or switched completely to using e-cigarettes. Pulmonary function tests showed small but non-statistically significant improvements in FVC and FEV1 measurements in most use groups. Statistically significant (p < 0.05) benefits associated with smoking reduction were also noted in exhaled CO and NO levels. All study products were well tolerated. The study findings suggest that there are potential cardiovascular and pulmonary function benefits when smokers switch to using e-cigarette products. This further reinforces the potential that e-cigarettes offer smokers seeking an alternative to conventional tobacco products.
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Presión Sanguínea/fisiología , Sistemas Electrónicos de Liberación de Nicotina , Frecuencia Cardíaca/fisiología , Pulmón/fisiopatología , Fumar/fisiopatología , Adulto , Flujo Espiratorio Forzado , Humanos , Pruebas de Función Respiratoria , Cese del Hábito de Fumar , Productos de Tabaco , Tabaquismo , Capacidad VitalRESUMEN
This work investigates influence of different aluminosillicate nanoparticles (NPs) which are found in air in selected workplaces on the properties of the phospholipid (DPPC) monolayer at air-saline interface considered as ex vivo model of the lung surfactant (LS). The measurements were done under physiological-like conditions (deformable liquid interface at 37 °C) for NP concentrations matching the calculated lung doses after exposure in the working environment. Measured surface pressure-area (π-A) isotherms and compressibility curves demonstrated NP-induced changes in the structure and mechanical properties of the lipid monolayer. It was shown that hydrophilic nanomaterials (halloysite and bentonite) induced concentration-dependent impairment of DPPC's ability of attaining high surface pressures on interfacial compression, suggesting a possibility of reduction of physiological function of natural LS. Hydrophobic montmorillonites affected DPPC monolayer in the opposite way; however, they significantly changed the mechanical properties of the air-liquid interface during compression. The results support the hypothesis of possible reduction or even degradation of the natural function of the lung surfactant induced by particle-phospholipid interactions after inhalation of nanoclays. Presented data do not only supplement the earlier results obtained with another LS model (animal-derived surfactant in oscillating bubble experiments) but also offer an explanation of physicochemical mechanisms responsible for detrimental effects which arise after deposition of inhaled nanomaterials on the surface of the respiratory system.
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Silicatos de Aluminio , Pulmón/efectos de los fármacos , Nanopartículas , Surfactantes Pulmonares , Animales , Arcilla , Pulmón/metabolismo , Modelos Biológicos , Fosfolípidos/metabolismoRESUMEN
PIP: This paper evaluates vaccines designed to prevent pneumonia among children in developing countries. Additionally, the article discusses the measurement of vaccine efficacy, as well as the potential of vaccine trials to provide information on the etiology of pneumonia and the need for an antibiotic treatment for various categories of acute respiratory infections (ARI). The three approaches to pneumococcal vaccine development include: 1) polysaccharide vaccines; 2) protein-polysaccharide conjugate vaccines; and 3) vaccines based on common protein antigens. The trial design was performed by individual randomization and randomization in clusters. Vaccines were evaluated in terms of the protection they provide against diseases with an unknown pathogen. The clinical and radiologic evaluation of pneumococcal vaccine trials served three related functions: 1) defining the ability of the vaccines to prevent severe pneumonia; 2) measuring the impact of the vaccine on the total burden of pneumonia that is defined by the World Health Organization; and 3) subdividing documented ARI episodes along clinical and radiological lines. Pneumococcal vaccine trials are essential in understanding the nature of pneumococcal disease among children in developing countries, as well as the public health utility of vaccines for its prevention.^ieng
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Vacunas Bacterianas , Países en Desarrollo , Neumonía Bacteriana/prevención & control , Vacunas Virales , Niño , Chile/epidemiología , Diseño de Investigaciones Epidemiológicas , Gambia/epidemiología , Vacunas contra Haemophilus , Humanos , Vacunas Neumococicas , Neumonía Neumocócica/prevención & control , Neumonía Viral/prevención & control , Virus Sincitiales Respiratorios , Streptococcus pneumoniaeRESUMEN
Smoking increases the risk of lung cancer and cardiovascular disease among persons of both sexes. The risk of cardiovascular disease is further increased among users of oral contraceptives who smoke, particularly those who are >/=35 years old or carry the coagulation factor V Leiden mutation. Other important cardiovascular disease risk factors in women include waist/hip girth ratio >0.8, high concentration of low-density lipoprotein cholesterol (>115 mg/dL), high triglyceride level (>/=150 mg/dL) with low concentration of high-density lipoprotein cholesterol (/=100 mg/dL, hypertension, lack of physical activity, and high-fat diet. Most excess cardiovascular disease among users of oral contraceptives is due to thrombosis (not atherosclerosis); studies indicate that the lower the oral contraceptive estrogen dose is, the lower is this risk. Oral contraceptives containing the third-generation progestins desogestrel and gestodene have been associated with greater risks of venous thromboembolism than are associated with older progestins, although there is some controversy surrounding these findings.
PIP: This paper examines the pathogenesis, epidemiology and risk of cardiovascular disease due to smoking and oral contraceptive (OC) use among women. The major risks associated with smoking were cardiovascular diseases and lung cancer. Characteristics of a syndrome which significantly increases the cardiovascular disease risk include: waist/hip girth ratio 0.8, glucose concentration 100 mg/dl, insulin 25 mU/l, peptide C 1.3 nmol/l, blood pressure 135/85 mm Hg, high triglyceride level 150 mg/dl with low concentration of HDL cholesterol (45 mg/d), total cholesterol/HDL ratio 4.0, LDL cholesterol (small dense pattern B) 130 mg/dl, uric acid concentration 7 mg/dl, and microalbuminuria 30-200 mg/dl. Women users over age 35 carrying the coagulation factor V Leiden mutation were found to be at increased risk of death from cardiovascular disease. The study indicates that increasing the estrogen dosage in an OC from 20 to 50 mcg ethinyl estradiol produced greater risks. Most cardiovascular disease among OC users is due to thrombosis. OCs containing the third-generation progestins desogestrel and gestodene have been associated with greater risks of venous thromboembolism that are associated with older progestins, although there is some controversy surrounding these findings. Smokers must be discouraged. When middle-aged women stopped smoking, about a third of their excess risk for coronary heart disease was eliminated within 2 years of cessation, and their risk became similar to that of nonsmoking women within 10-14 years.
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Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/etiología , Anticonceptivos Orales/efectos adversos , Fumar/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Femenino , Humanos , Factores de RiesgoRESUMEN
We conducted a randomized clinical trial to compare the effects of a synthetic (Exosurf) and natural (Survanta) surfactant in infants with neonatal respiratory distress syndrome. Eighty-nine patients were randomly allocated to receive one of the two surfactants. Primary outcome variables were the acute and long-term effects of the surfactant preparations, i.e., ventilatory requirements at 24 h of age as judged by the oxygenation index (OI), and the combined incidence of chronic lung disease or death at 28 days. The OIs in the Exosurf and Survanta groups at 24 h were the same (10.1 and 7, respectively; P > 0.05). The magnitude and rapidity of response, however, were greater for Survanta than for Exosurf. When arterial/alveolar oxygen tension ratios (a/A) were compared, the Exosurf group had a significantly worse a/A ratio at 24 h than the Survanta group (0.21 Exosurf vs. 0.37 Survanta; P < 0.05). The long-term outcome as judged by the combined incidence of death or chronic lung disease was not different in the two groups (18.6% Exosurf vs. 15.2% Survanta; P > 0.05). When the complications of prematurity were compared, there were no statistically significant differences between the two groups. We conclude that both preparations are reasonable choices for the treatment of respiratory distress syndrome of prematurity.
PIP: This study compares the effects of synthetic (Exosurf) and natural (Survanta) surfactants on infants with neonatal respiratory distress syndrome in Oman. Subjects included 89 patients, randomly allocated to receive one of the two surfactants. Results suggest that 43 and 46 of the total infants enrolled in the study were randomized to the Exosurf and Survanta groups, respectively. The oxygenation index in the Exosurf and Survanta groups at 24 hours were the same (10.1 and 7, respectively; P 0.05). The magnitude and rapidity of response, however, were greater for Survanta than for Exosurf. Moreover, when arterial/alveolar oxygen tension ratios (a/A) were compared, the Exosurf group had a significantly worse a/A ratio at 24 hours than the Survanta group. There were no statistically significant differences between the two groups when the complications of prematurity were compared. In conclusion, both preparations offer reasonable choices in the treatment of the respiratory distress syndrome. However, this should be weighed against the minor theoretical risks of transmission of infectious agents in a natural preparation, and the easier storage and transport of the synthetic surfactant.
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Productos Biológicos , Países en Desarrollo , Alcoholes Grasos/uso terapéutico , Fosforilcolina , Polietilenglicoles/uso terapéutico , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Análisis de los Gases de la Sangre , Combinación de Medicamentos , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Omán/epidemiología , Respiración Artificial , Síndrome de Dificultad Respiratoria del Recién Nacido/sangre , Síndrome de Dificultad Respiratoria del Recién Nacido/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: Mortality from asthma increased and is now declining in some countries, but little is known about these trends in South America. OBJECTIVE: We aimed to assess trends in mortality from asthma in southern Brazil in children and young adults. METHODS: Death certificates of 425 people in the state of Rio Grande do Sul aged between 5 and 39 years in whom asthma was reported to be the underlying cause of death during the period 1970 to 1992 were reviewed. Population data were available in 10-year age groups. Testing for trends in mortality rates was conducted using linear and log-linear regression procedures. RESULTS: Asthma mortality rates in the age groups 5 to 19 and 20 to 39 years ranged between 0.04 and 0.39/100,000 and 0.28 to 0.75/100,000, respectively, and were nonuniformly distributed over the study period. The mean annual increase in rate in 5- to 19-year olds was +0.01 (95% CI 0.003 to 0.016), an average annual percentage increase of +6.8% (95% CI 3% to 11%), with a total increase of 352% between 1970 and 1992. This increase was not due to a shift in labeling from bronchitis to asthma. In the 20 to 39-year age group, asthma and bronchitis mortality rates showed no trend to increase or decrease. CONCLUSIONS: Asthma mortality in southern Brazil is low, but rose significantly between 1970 and 1992 in the 5 to 19-year age group. This trend differs from that found in other states of Brazil and several other Latin American countries. Reasons for this difference remain unclear.
PIP: Levels of mortality due to asthma are declining in some countries. To measure trends in mortality from asthma in southern Brazil among children and young adults, the death certificates of 425 people in the state of Rio Grande do Sul aged 5-39 years in whom asthma was reported to be the underlying cause of death during the period 1970-92 were reviewed. Asthma mortality rates among people aged 5-19 and 20-39 years were 0.04-0.39/100,000 and 0.28-0.75/100,000, respectively, and were nonuniformly distributed over the study period. The mean annual increase in mortality rate among 5-19 year olds was 0.01, an average annual percentage increase of 6.8%, with a total increase of 352% during 1970-92. This increase was not due to a shift in labeling from bronchitis to asthma. Among people aged 20-39 years, asthma and bronchitis mortality rates showed no trend of increase or decrease. Reasons for the dramatic increase in asthma-related mortality among 5-19 year olds are unclear.
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Asma/mortalidad , Adolescente , Adulto , Brasil/epidemiología , Bronquitis/mortalidad , Niño , Preescolar , Certificado de Defunción , Femenino , Humanos , Masculino , Mortalidad/tendencias , Dinámica PoblacionalRESUMEN
PIP: A 5-year plan to cut childhood deaths from asthma by half has been announced by WHO in association with other international respiratory organizations. The initiative aims to cut the estimated 25,000 avoidable asthma related deaths that occur in children each year. Other targets include cutting the number of childhood hospitalizations due to asthma by at least a quarter and the number of school days lost by half. Moreover, the project is focusing on children because of the strong evidence that the incidence of asthma is increasing rapidly in this age group throughout the world. The immediate strategies proposed to meet the targets set by the initiatives include encouraging health service providers to make provision for sufficient numbers of well educated health professionals to allow access to specialist care. Furthermore, particular emphasis is also being placed on preventive treatment.^ieng
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Asma/mortalidad , Asma/prevención & control , Niño , Salud Global , Promoción de la Salud , Humanos , Organización Mundial de la SaludRESUMEN
PIP: As public smoking and tobacco advertising are increasingly banned in North America and Europe, tobacco companies are likely to attempt to boost their sales in other parts of the world: Africa, Asia, the Caribbean, and the former Communist states in Eastern Europe. The current epidemic of chronic obstructive pulmonary disease (COPD) will be transferred to these countries as well. COPD can be definitively diagnosed only by spirometry. The median survival time is 5-10 years. In the long run, the most effective treatment will be smoking cessation programs. Pharmaceutical interventions include bronchodilators and, for a minority of patients, inhaled steroids. Domiciliary oxygen should be provided only when there is demonstrable hypoxia. The British Thoracic Society guidelines on COPD are relevant to developing countries as well as the UK.^ieng
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Países en Desarrollo , Enfisema , Directrices para la Planificación en Salud , Pulmón , Fumar , Terapéutica , Américas , Conducta , Biología , Región del Caribe , Enfermedad , América del Norte , FisiologíaRESUMEN
BACKGROUND: The relationship between sex hormones and asthma has not been clarified. Studies have suggested a potential beneficial effect of exogenous sex hormones and/or contraceptive pills on asthma in premenopausal females whereas the data for postmenopausal females are inconsistent. CASE REPORT: A 33-year-old woman suffering from asthma with premenstrual exacerbations had a stable course until she began taking oral contraceptives. At that time she experienced clinical deterioration of her asthma associated with decline of pulmonary function tests. No other precipitating factors were identified. After discontinuing the contraceptives, her condition returned to baseline. CONCLUSION: We found only two reports of worsening of asthma related to hormonal therapy (estrogen in one case, contraceptive pills in the other) in premenopausal women. Our report, together with these observations, suggests that in some premenopausal women exogenous sex hormones and/or contraceptive pills may, contrary to expected, produce exacerbation of asthma.
PIP: Although the mechanism of premenstrual asthma has not been established, hormonal variations during the menstrual cycle are believed to play an important role. About 30-40% of female asthmatics report worsening of asthma symptoms during the premenstrual and/or menstrual period. This article presents a case in which oral contraceptives (OCs) appeared to precipitate an asthma attack. The patient, a 33-year-old White US woman, first developed asthma at age 27 years. The strongest trigger to her asthma attacks was her menstrual period. All periods were associated with a worsening of asthma, typically extending from 1 week before to 2-3 days after the onset of menstrual bleeding. Subsequently, the patient's asthma was stabilized by continuous inhaled steroids. However, clinical deterioration of asthma and a decline of pulmonary function occurred immediately after the woman initiated OC use. There was a rapid stabilization in clinical status once OC use was discontinued. Although the weight of scientific evidence points to a possible beneficial effect of OCs or exogenous sex hormones on premenstrual asthma, this case suggests there may be a subset of women in whom sex hormones exacerbate asthma.
Asunto(s)
Asma/inducido químicamente , Anticonceptivos Orales/efectos adversos , Síndrome Premenstrual/complicaciones , Adulto , Femenino , Humanos , Pruebas de Función Respiratoria , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: To study the effect of early postnatal dexamethasone therapy on severity of hyaline membrane disease. DESIGN: Prospective, randomized, controlled, unblinded study. SETTING: Neonatal Intensive Care Unit. METHODS: 19 babies who had hyaline membrane disease were included in this study. The inclusion criteria were clinical and radiographic diagnosis of RDS, requiring mechanical ventilation and FiO2 > 0.3. Ten babies received injection dexamethasone 0.5 mg/kg/dose 12 hourly for 3 days starting within 6 hours of birth. The control group did not receive any drug. Babies with active infection, bleeding tendency and congenital malformation were excluded. None of the babies received surfactant. The duration of ventilation and AaDO2 and FiO2 requirements from day one to five were calculated. RESULTS: The initial AaDO2 were similar in both the groups but on day 3, 4, 5 AaDO2 were low in study group (201, 85, 70) compared to control group (236, 209, 162). The initial FiO2 were 0.66 and 0.63 in dexamethasone and control groups, respectively and remained high till day 2 and came down in study group on days 3, 4 and 5 (0.41, 0.27, 0.27) compared to control group (0.53, 0.34, 0.42). The mean duration of ventilation was shorter in dexamethasone group (87 hours) vs control group (120 hours). CONCLUSION: Early use of postnatal dexamethasone reduces the disease severity and oxygen requirement in RDS and hence would be useful in the Indian context.
PIP: 19 infants with hyaline membrane disease participated in a study to assess the effect of early postnatal dexamethasone therapy upon the severity of their disease. 10 patients received injected dexamethasone of 0.5 mg/kg/dose 12-hourly for 3 days beginning within 6 hours of birth, while the control group received no drug. Infants with active infection, bleeding tendency, and congenital malformation were excluded from the study, and no infant received surfactant. Initial alveolar arterial oxygen gradient (AaDO(2)) levels were similar in both groups, but were lower in the study group at days 3-5. Initial fraction of inspired oxygen (FiO(2)) levels were 0.66 and 0.63 in the dexamethasone and control groups, respectively, and remained high until day 2, then decreased in the study group to levels below those in the control group on days 3-5. The mean duration of ventilation was 87 hours in the dexamethasone group and 120 hours in the control group. These findings indicate that the early use of postnatal dexamethasone reduces the disease severity and oxygen requirement in respiratory distress syndrome, and as such, would be useful in India.
Asunto(s)
Antiinflamatorios/uso terapéutico , Dexametasona/uso terapéutico , Enfermedad de la Membrana Hialina/tratamiento farmacológico , Femenino , Humanos , Enfermedad de la Membrana Hialina/diagnóstico , Enfermedad de la Membrana Hialina/mortalidad , India , Recién Nacido , Masculino , Pronóstico , Estudios Prospectivos , Pruebas de Función Respiratoria , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
Estimates of the incidence of pulmonary tuberculosis in developing countries are based on case reporting from local health laboratories or the annual risk of tuberculin skin test conversion. Because these methods are problematic, the authors used a multiple case ascertainment method to estimate the incidence of pulmonary tuberculosis from 1989 to 1993 in a Peruvian shantytown of 34,000 inhabitants. Two methods, face-to-face interview of all local inhabitants and examination of local laboratory smear records, were used for case gathering. The number of missed cases was estimated by capture-recapture analysis. Survey cases with positive smears were matched to age- and sex-matched controls and interviewed about socioeconomic conditions. The average annual incidence per 100,000 population was 364 (95% confidence interval 293-528) by capture-recapture methods. For the city encompassing the shantytown, the Peruvian Ministry of Heath reported an average annual incidence of 134 cases per 100,000 population. The authors conclude that, in Peru, alarming clusters of pulmonary tuberculosis are masked by government reports that pool zones of disparate incidence. Existing estimators of pulmonary tuberculosis incidence based on tuberculin conversion rates may be invalid in such areas. Within these hyperendemic areas, persons suitable for intensive prophylaxis efforts cannot be reliably identified by housing and socioeconomic risk factors.
PIP: A multiple case ascertainment method was used to estimate the incidence of pulmonary tuberculosis in 1989-93 in a shantytown with 34,000 residents near Lima, Peru. Face-to-face interviews with all residents yielded 191 reports of smear-positive tuberculosis diagnoses at shantytown laboratories and 97 diagnoses from out-of-town laboratories during the study period. Local laboratory smear records identified 354 positive smears, confirming the oral reports of 139 residents (73%) who reported diagnoses at local laboratories. The number of missed cases was estimated by capture-recapture analysis. An average annual incidence of 364 pulmonary tuberculosis cases per 100,000 population was calculated. In contrast, an average annual incidence of 134 cases/100,000 was reported by the Peruvian Ministry of Health for the city (South Lima) encompassing the shantytown. For hyperendemic areas such as shantytowns, various household and socioeconomic factors have been proposed as screening tools to identify those at risk of tuberculosis and in need of chemoprophylaxis. Survey cases with positive smears were matched with controls by age and sex and interviewed about socioeconomic conditions. Logistic regression analysis identified three socioeconomic factors that were protective against pulmonary tuberculosis: a longer residence in the shantytown (odds ratio (OR), 0.91/year; 95% confidence interval (CI), 0.82-0.99), a larger number of doors in the home (OR, 0.80/door; 95% CI, 0.70-0.93), and recent consumption of alcohol (OR, 0.61; 95% CI, 0.29-1.01). The positive predictive value of a model comprised of these three factors was below 1%, however. These findings indicate that clusters of tuberculosis cases in areas such as shantytowns may be masked by their proximity to areas of lower incidence in the absence of special case finding efforts.