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1.
J Geophys Res Atmos ; 127(13): e2022JD036733, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-36249538

RESUMEN

Plant stress in a changing climate is predicted to increase plant volatile organic compound (VOC) emissions and thus can affect the formed secondary organic aerosol (SOA) concentrations, which in turn affect the radiative properties of clouds and aerosol. However, global aerosol-climate models do not usually consider plant stress induced VOCs in their emission schemes. In this study, we modified the monoterpene emission factors in biogenic emission model to simulate biotic stress caused by insect herbivory on needleleaf evergreen boreal and broadleaf deciduous boreal trees and studied the consequent effects on SOA formation, aerosol-cloud interactions as well as direct radiative effects of formed SOA. Simulations were done altering the fraction of stressed and healthy trees in the latest version of ECHAM-HAMMOZ (ECHAM6.3-HAM2.3-MOZ1.0) global aerosol-climate model. Our simulations showed that increasing the extent of stress to the aforementioned tree types, substantially increased the SOA burden especially over the areas where these trees are located. This indicates that increased VOC emissions due to increasing stress enhance the SOA formation via oxidation of VOCs to low VOCs. In addition, cloud droplet number concentration at the cloud top increased with increasing extent of biotic stress. This indicates that as SOA formation increases, it further enhances the number of particles acting as cloud condensation nuclei. The increase in SOA formation also decreased both all-sky and clear-sky radiative forcing. This was due to a shift in particle size distributions that enhanced aerosol reflecting and scattering of incoming solar radiation.

2.
Scand J Infect Dis ; 33(8): 625-7, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11525360

RESUMEN

A previously healthy 6-y-old girl presented with a disease very similar to pneumococcal pneumonia. However, Moraxella osloensis was isolated by lung tap. The patient responded well to a course of parenteral penicillin. This is probably the first documented case of community-acquired pneumonia associated with this agent. Clinical isolates of M. osloensis are rare and its pathogenesis has not been delineated; however, a literature review suggests that the organism is more common than is generally recognized.


Asunto(s)
Moraxella/aislamiento & purificación , Infecciones por Neisseriaceae/diagnóstico , Neumonía Bacteriana/diagnóstico , Niño , Diagnóstico Diferencial , Femenino , Humanos , Infecciones por Neisseriaceae/microbiología , Neumonía Bacteriana/microbiología , Neumonía Neumocócica/diagnóstico , Resultado del Tratamiento
3.
Int J Infect Dis ; 5(1): 3-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11285152

RESUMEN

OBJECTIVES: To explore whether 4-day parenteral beta-lactam therapy is as effective as 7-day therapy for children hospitalized for parenteral antimicrobials. METHODS: A series of patients aged 3 months to 15 years who fulfilled strict criteria for bacterial pneumonia, other respiratory infections, sepsis-like infections, and other acute infections were prospectively randomized to receive parenteral penicillin or cefuroxime randomly for 4 or 7 days. Besides blood and throat cultures, the etiology was searched by serology for 23 different agents. RESULTS: Of 154 children analyzed, a probable etiology was established in 96. Of those, a bacterial infection, with or without concomitant viral infection, was disclosed in 80% and 94% in the 4-day and 7-day treatment groups, respectively; pneumococcus being the commonest agent. There was one possible treatment failure in the 4-day group, but with a questionable relation to the short course. Three patients in the 4-day and two in the 7-day group underwent treatment changes, or were rehospitalized within 30 days. All children recovered entirely. CONCLUSIONS: Shortening parenteral beta-lactam treatment to 4 days in infections for which most parenteral antimicrobials are instituted, is not only safe, but reduces costs, is ecologically sound, and minimizes the risks of nosocomial infections and other adverse effects of treatment.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Cefuroxima/administración & dosificación , Cefuroxima/uso terapéutico , Penicilinas/administración & dosificación , Penicilinas/uso terapéutico , Adolescente , Infecciones Bacterianas/microbiología , Cefuroxima/efectos adversos , Cefuroxima/farmacología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Pruebas de Sensibilidad Microbiana , Penicilinas/efectos adversos , Penicilinas/farmacología , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/microbiología , Distribución Aleatoria , Sepsis/tratamiento farmacológico , Sepsis/microbiología , Pruebas Serológicas , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/aislamiento & purificación , Factores de Tiempo , Resultado del Tratamiento
4.
Clin Infect Dis ; 32(5): 715-26, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11229839

RESUMEN

Identification of the etiology of childhood pneumonia is difficult, even in the cases that most likely have bacterial origins. A positive blood culture result is diagnostic but rare (< 10% of cases), and other noninvasive microbiological methods are nonspecific or are at least shadowed by interpretation problems. However, lung tap (or aspiration), a method developed a century ago, warrants reappraisal, especially since the prevalence of pneumococcal resistance to penicillin is increasing. An analysis of 59 studies that were published in 6 languages led us to conclude that (1) bacterial etiology is disclosed in approximately 50% of cases (virological tests were rarely done); (2) lung tap is safer than is generally considered; (3) potential pneumothorax is mostly symptomless and resolves spontaneously without impairing recovery; and (4) in comparison with routine diagnostic tools, lung tap offers so many advantages that it warrants reconsideration at centers where personnel have experience in handling potential pneumothorax.


Asunto(s)
Biopsia con Aguja , Neumonía Bacteriana/diagnóstico , Neumonía Viral/diagnóstico , Adolescente , Biopsia con Aguja/efectos adversos , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Pulmón/microbiología , Pulmón/patología , Pulmón/virología , Neumonía Bacteriana/microbiología , Neumonía Viral/virología
5.
Pediatr Infect Dis J ; 20(1): 52-8, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11176567

RESUMEN

BACKGROUND: Little is known of the etiology of childhood acute lower respiratory infections in China, where the use of antimicrobials is indiscriminate. Trials to change such a policy require etiologic data, especially on the bacteria most relevant to these common diseases. METHODS: One hundred consecutive infants and children from 3 months to 14 years of age with symptoms and signs compatible with acute lower respiratory infections were studied prospectively in the largest pediatric hospital in Beijing from February to May, 1997. Blood culture, thorax radiography and paired sera for 20 microbiologic assays were taken, and the course of illness was monitored uniformly. Disease severity was graded. RESULTS: In 24 cases there was evidence only of bacterial etiology, and in 5 solely viral agents were found; 3 children probably had a mixed bacterial-viral infection. Surprisingly no pneumococcal infection was detected, Mycoplasma pneumoniae (n = 21), Haemophilus influenzae type b (n = 8) and Chlamydia pneumoniae (n = 7) being the dominant bacteria. All children recovered. CONCLUSIONS: Routine use of antimicrobials for these patients seems unjustified. Serologic evidence for the H. influenzae type b etiology is encouraging in terms of vaccination, but confirmatory studies are needed.


Asunto(s)
Infecciones del Sistema Respiratorio/etiología , Adolescente , Antibacterianos/uso terapéutico , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/etiología , Infecciones Bacterianas/microbiología , Niño , Preescolar , China/epidemiología , Pruebas de Fijación del Complemento , Contraindicaciones , Femenino , Humanos , Técnicas para Inmunoenzimas , Lactante , Masculino , Estudios Prospectivos , Radiografía Torácica , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/microbiología , Virosis/epidemiología , Virosis/etiología , Virosis/virología
6.
Eur J Pediatr ; 159(12): 878-84, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11131342

RESUMEN

UNLABELLED: Overuse of broad-spectrum antimicrobials has resulted in increasing bacterial resistance in many countries. We hypothesised that common childhood infections requiring parenteral medication are still curable with narrow-spectrum and inexpensive penicillin. A prospective and randomised study was performed in two referral hospitals in Helsinki. A total of 154 children aged 3 months to 15 years with pneumonia or other lower respiratory infections, sepsis-like infections, or other common acute infections warranting hospitalisation and parenteral antimicrobials were included. At random, 50% of children received procaine penicillin intramuscularly, the other 50% cefuroxime intravenously for 4-7 days. The course of illness was monitored with predetermined laboratory and radiological indices, by filling in a special form daily and a follow-up for 30 days after discharge. The infectious agent was searched for with a large laboratory set-up covering 23 bacterial, viral or protozoan species. The two groups were very similar at presentation. Probable aetiology was disclosed in 56% of the penicillin and in 68% of the cefuroxime recipients, the leading agent in both groups being Pneumococcus. In 8% only a viral aetiology was found. The children recovered with the same speed, regardless of which antimicrobial used, there being one possible failure in each group but no difference in the frequency of needing a physician again within 1 month of discharge. No adverse event was attributable to either drug. CONCLUSION: Procaine penicillin is as effective and safe as cefuroxime for common community-acquired infections in immunocompetent children.


Asunto(s)
Cefuroxima/uso terapéutico , Cefalosporinas/uso terapéutico , Enfermedades Transmisibles/tratamiento farmacológico , Penicilina G Procaína/uso terapéutico , Penicilinas/uso terapéutico , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Estudios Prospectivos
7.
Rhinology ; 34(1): 21-3, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8739863

RESUMEN

The efficacy and side effects of once-daily astemizole-D, a combination of 10 mg astemizole and 240 mg pseudoephedrine, were compared with those of twice-daily brompheniramine-D, a combination of 12 mg brompheniramine and 50 mg phenylpropanolamine (Lunerin), in 64 patients with seasonal allergic rhinitis caused by birch pollen. Efficacy was monitored by patient's diary scores, investigator assessments of nasal and eye symptoms and need of rescue medication during the 4-week study period. Both astemizole-D and brompheniramine-D reduced nasal and eye symptoms of allergy. There were no significant differences between the treatment groups regarding obstruction, but brompheniramine-D alleviated symptoms of rhinorrhoea and itchy eyes significantly more than astemizole-D. On the other hand, the patients in the brompheniramine-D group reported dry mouth, tiredness and drowsiness more often than those in the astemizole-D group. The results indicate that the two drugs are effective in the treatment of seasonal allergic rhinitis, but astemizole-D is better tolerated than brompheniramine-D.


Asunto(s)
Astemizol/uso terapéutico , Efedrina/uso terapéutico , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Rinitis Alérgica Estacional/tratamiento farmacológico , Simpatomiméticos/uso terapéutico , Adolescente , Adulto , Alérgenos/efectos adversos , Astemizol/efectos adversos , Bromofeniramina/efectos adversos , Bromofeniramina/uso terapéutico , Niño , Combinación de Medicamentos , Efedrina/efectos adversos , Femenino , Antagonistas de los Receptores Histamínicos H1/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Fenilpropanolamina/efectos adversos , Fenilpropanolamina/uso terapéutico , Proyectos Piloto , Polen , Método Simple Ciego , Simpatomiméticos/efectos adversos
9.
Rhinology ; 29(4): 301-6, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1780632

RESUMEN

Information on the long-term clinical course of hypersensitive rhinitis was collected among 180 patients who had previously participated in an allergological study. The time period between the initial study and the follow-up questionnaire study was about 18.2 years. Of the patients, 72 were men and 108 women, aged 3.6-69.3 years (mean age 28.5 years) at the time of the initial study. Initially, atopic rhinitis had been verified by allergological investigations in 61.7% while 38.3% of the cases had been designated as intrinsic. During the 18-year period symptoms decreased in severity in 37.2% and ceased completely in 27.2%. Total disappearance of symptoms was more frequent in the intrinsic than in the atopic group.


Asunto(s)
Rinitis Alérgica Estacional , Estudios de Seguimiento , Humanos , Remisión Espontánea , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Perenne/terapia , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/terapia
10.
Rhinology ; 29(2): 137-41, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1891681

RESUMEN

Sixty patients with seasonal allergic rhinitis due to birch pollen were enrolled in an open, randomized parallel group study. Efficacy and side effects were studied after intranasal administration of budesonide given as a freon propellant aerosol or as dry powder with a sniff actuated inhalation device. Medication started a few days before the actual peak pollen season and lasted for three weeks. The dose was 400 micrograms once daily. Efficacy was assessed daily by patient-rated symptoms scores and by nasal peak inspiratory flow measurements at the visits to the clinic. Safety was assessed by monitoring clinical adverse events. No clear changes in nasal symptom scores or nasal peak flow occurred during the pollen season in either treatment group as compared to the pretreatment period, although the pollen season was very difficult in Finland during the study, ad 12000 grains per m3. Substantial or total control of symptoms was achieved in 93% of the patients in the aerosol group and in 79% in the powder group. Side effects were minimal in both groups. We conclude that dry powder administration of budesonide is as effective and well tolerated as the aerosol in the treatment of seasonal allergic rhinitis.


Asunto(s)
Antiinflamatorios/uso terapéutico , Pregnenodionas/administración & dosificación , Rinitis Alérgica Estacional/tratamiento farmacológico , Administración por Inhalación , Administración Tópica , Adulto , Aerosoles , Budesonida , Femenino , Glucocorticoides , Humanos , Masculino , Polvos , Pregnenodionas/uso terapéutico
11.
Clin Exp Allergy ; 19(6): 603-8, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2574626

RESUMEN

The efficacy of terfenadine in combination with phenylpropanolamine was assessed by comparison with terfenadine alone in a double-blind, parallel group study of 66 patients with nasal birch pollen allergy. The patients were allocated randomly into two groups; 34 patients received terfenadine (60 mg) twice daily and 32 patients a combination tablet containing terfenadine (60 mg) and phenylpropanolamine (50 mg) twice daily for 17 days during the birch pollen season. Nasal symptoms (sneezing, discharge, itching and blockage) were relieved significantly by both drugs, but control of symptoms was more rapid and better with the terfenadine-phenylpropanolamine combination. Rhinoscopic evaluation of nasal secretion and mucosal swelling showed no differences between the treatment groups. Compared with pre-season values, nasal peak expiratory flow (PEF)-values worsened significantly during the season in the terfenadine, but not in the terfenadine-phenylpropanolamine, group. The general condition of the patients was significantly better in the terfenadine-phenylpropanolamine group. There were no marked side-effects in either group. At the end of the trial some of the patients in both treatment groups still had symptoms; this is apparently due to the long-lasting and severe pollen season. It is concluded that terfenadine combined with phenylpropanolamine gives better control of seasonal allergic rhinitis than terfenadine alone.


Asunto(s)
Compuestos de Bencidrilo/administración & dosificación , Fenilpropanolamina/administración & dosificación , Rinitis Alérgica Estacional/tratamiento farmacológico , Método Doble Ciego , Quimioterapia Combinada , Femenino , Antagonistas de los Receptores Histamínicos H1/administración & dosificación , Humanos , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Terfenadina
12.
Acta Otolaryngol ; 107(5-6): 446-9, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2474232

RESUMEN

Nasal reactions to unilateral allergen provocation were studied separately in both nasal cavities of 9 subjects with established seasonal allergic rhinitis. Three tests with the same allergen at the same concentration were performed in the same cavity at 48-h intervals. The parameters observed were clinical symptoms, changes in nasal airway resistance on rhinomanometry, and amount, weight and histamine content of the collected secretion. Nasal obstruction increased significantly on the provoked side but not contralaterally. Secretion increased symmetrically but the histamine content rose only on the provoked side. No priming effect was observed. The results are compatible with the view that the release of histamine has a 2-fold effect. Histamine directly caused vasodilatation of capacitance vessels and capillaries, which resulted in obstruction on the provoked side, and indirectly the histamine release led to stimulation of sensory nerve endings, which by triggering parasympathetic reflexes caused rhinorrhea in both nasal halves.


Asunto(s)
Pruebas de Provocación Nasal/métodos , Rinitis Alérgica Estacional/diagnóstico , Adulto , Resistencia de las Vías Respiratorias , Alérgenos , Liberación de Histamina , Humanos , Cavidad Nasal , Mucosa Nasal/metabolismo
13.
Rhinol Suppl ; 8: 59-64, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2772495

RESUMEN

Recurrence of nasal polyposis after polypectomy or ethmoidectomy was studied in 85 patients four years after surgery. The patients were classified into one of three groups according to clinical findings: an atopy group (history confirmed by skin test or nasal provocation), an acetylsalicylic acid intolerance (ASA) group (confirmed by provocation), or an "intrinsic" group (no specific diagnosis). The risk of recurrence was significantly greater in patients with ASA intolerance than in the other two patient groups; the frequency of reoperations during the follow-up period was significantly higher in the ASA group and the need for topical corticosteroid treatment had also been more frequent. Bronchial asthma was diagnosed in 40% of all patients. Asthma was significantly more often associated with ASA group (91%) vs 46% at AT and in only 16% at INTR group.


Asunto(s)
Pólipos Nasales/cirugía , Recurrencia Local de Neoplasia/cirugía , Corticoesteroides/administración & dosificación , Aspirina/efectos adversos , Asma/complicaciones , Hipersensibilidad a las Drogas/complicaciones , Senos Etmoidales/cirugía , Estudios de Seguimiento , Humanos , Reoperación , Factores de Riesgo
15.
J Allergy Clin Immunol ; 79(4): 585-90, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2951426

RESUMEN

The aim of the present study was to test the efficacy of the topically active cholinoceptor antagonist, ipratropium, in the treatment of rhinorrhea in perennial nonallergic rhinitis, with special reference to identification of subgroups of responders and increased efficacy from high-dose therapy. Thirty-six adult patients with watery rhinorrhea as a dominant symptom completed the study, which consisted of a 2-week run-in period followed by two 3-week treatment periods with placebo and ipratropium in an ordinary dosage (80 micrograms four times a day) in a double-blind, crossover design, and, finally, an open 2-week period with high-dose therapy (400 micrograms four times a day). The number of nose blowings was 47% lower during treatment with ipratropium in the ordinary dosage than during the placebo period (p less than 0.001). There was an additional reduction during high-dose therapy that was slight but statistically significant (p less than 0.05). Ipratropium had no effect on the number of sneezes or on nasal blockage index. During ordinary-dose therapy, side effects were slight and confined to the nose, whereas the high-dose therapy caused unpleasant nasal dryness and, in a few cases, systemic side effects. It was not possible to separate responders from nonresponders by case history, physical examination, or nasal methacholine testing. It is concluded that intranasal ipratropium is effective in the treatment of watery rhinorrhea in perennial nonallergic rhinitis and that 320 micrograms a day is sufficient in most patients.


Asunto(s)
Derivados de Atropina/administración & dosificación , Ipratropio/administración & dosificación , Rinitis/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos como Asunto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Humanos , Ipratropio/uso terapéutico , Masculino , Persona de Mediana Edad , Pruebas de Provocación Nasal
16.
Rhinology ; 24(4): 265-9, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-3823748

RESUMEN

The effects of a special balanced physiological saline on nasal symptoms of 93 patients with chronic rhinitis were studied. The main diagnoses of the patients were allergic rhinitis, atrophic rhinitis and ozaena, rhinitis sicca, chronic sinusitis, nasal polyposis and postoperative condition after nasal surgery. The tested solution was administered by a simple metered dose pump. 85 (91%) of the patients reported beneficial effects of the tested solution on nasal symptoms. In addition, 22 (71%) of those patients who used continuous anti-allergic medication, mainly intranasal steroids, reported that the tested solution improved the efficacy of their ordinary drug. So the tested solution proved to be beneficial in humidifying atrophic or otherwise dry mucosa, douching crusty nose and as adjuvant therapy in the treatment of allergic rhinitis.


Asunto(s)
Rinitis/terapia , Cloruro de Sodio/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rinitis/etiología , Irrigación Terapéutica
18.
Rhinology ; 22(4): 255-60, 1984 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6522975

RESUMEN

Clinical observations, X-ray findings and results of laboratory tests were evaluated in 770 patients with allergic rhinitis. Anamnestic data and results of the allergological examination of these patients have been presented elsewhere (Holopainen et al., 1979b; Binder et al., 1982). Allergic symptoms were seasonal in 54.5% and perennial in 45.5% of the patients. Mucosal changes as seen on rhinoscopy were significantly more common among patients with perennial than among patients with seasonal rhinitis. Watery discharge was the most common nasal finding, observed in 90% of all patients. Nasal smears showed increased numbers of eosinophilic leucocytes in 70% of the cases. Relationships between the cellular population of the nasal secretion, other laboratory test results and clinical findings are described. X-ray examination revealed pathological changes in the paranasal sinuses in 53.4% of the patients.


Asunto(s)
Mucosa Nasal/patología , Rinitis Alérgica Perenne/patología , Rinitis Alérgica Estacional/patología , Adolescente , Adulto , Niño , Citodiagnóstico , Eosinofilia/complicaciones , Femenino , Humanos , Hipertrofia , Masculino , Persona de Mediana Edad , Cavidad Nasal/patología , Mucosa Nasal/metabolismo , Pólipos Nasales/complicaciones , Rinitis Alérgica Perenne/complicaciones , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Estacional/complicaciones , Rinitis Alérgica Estacional/diagnóstico
20.
Acta Otolaryngol ; 97(5-6): 443-9, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6464702

RESUMEN

One hundred and ninety-three middle ear effusion samples from patients with acute otitis media were studied for cellular content and bacteria. Findings were compared with clinical and radiological data. In samples positive for pathogenic bacteria (Haemophilus, pneumococci) neutrophils predominated, whereas monocytes or phagocytes were more numerous in samples with nonpathogens. Inflammatory cells were more frequent in large than in small mastoid air cell systems. Destruction of cell walls was associated with increase of neutrophils and sclerosis with preponderance of lymphocytes, monocytes and phagocytes.


Asunto(s)
Otitis Media/patología , Enfermedad Aguda , Basófilos/patología , Niño , Eosinófilos/patología , Femenino , Humanos , Recuento de Leucocitos , Linfocitos/patología , Masculino , Monocitos/patología , Neutrófilos/patología , Fagocitos/patología
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