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E Patrick

Publications and source records attributed to E Patrick.

18 recordsLinked to original sources
PubMed2001

Broad-spectrum mildew resistance in Arabidopsis thaliana mediated by RPW8.

Plant disease resistance (R) genes control the recognition of specific pathogens and activate subsequent defense responses. We show that the Arabidopsis thaliana locus RESISTANCE TO POWDERY MILDEW8 (RPW8) contains two naturally polymorphic, dominant R genes, RPW8.1 and RPW8.2, which individually control resistance to a broad range of powdery mildew pathogens. Although the predicted RPW8.1 and RPW8.2 proteins are different from the previously characterized R proteins, they induce localized, salicylic acid-dependent defenses similar to those induced by R genes that control specific resistance. Apparently, broad-spectrum resistance mediated by RPW8 uses the same mechanisms as specific resistance.

Alleles↗
PubMed1999

Pleuropulmonary blastoma and ovarian teratoma.

We report a patient with pleuropulmonary blastoma who had a benign teratoma as a second primary tumor. The radiology, clinical course, and the biological importance of this rare neoplasm are discussed.

Adolescent↗
PubMed1997

Longitudinal evaluation of severely anemic children in Kenya: the effect of transfusion on mortality and hematologic recovery.

OBJECTIVE: To determine the effect of transfusion on hematologic recovery and mortality among severely anemic children during and after hospitalization in rural Kenya. DESIGN: Prospective cohort. METHODS: We collected clinical and laboratory information on all severely anemic children (hemoglobin < 5.0 g/dl) and a 33% sample of children with hemoglobin < or = 5.0 g/dl who were admitted to the pediatric ward of a rural Kenyan hospital during a 6 month study period. Children were followed during hospitalization and at 4 and 8 weeks after admission. RESULTS: Overall, 303 (25%) of the 1223 hospitalized children had hemoglobin < 5.0 g/dl, 30% of whom died during the study period. Severely anemic children who were transfused had a higher mean hemoglobin level at discharge (9.0 g/dl) than non-transfused children (5.8 g/dl, P < 0.001) and maintained a higher mean hemoglobin during the 8-week follow-up period. However, the presence of malaria parasitemia on follow-up negated the benefit of transfusion on hematologic recovery at both 4- and 8-week visits (longitudinal linear model, least square means, P > 0.05). Transfusion was associated with improved survival among children with respiratory distress who received transfusions within the first 2 days of hospitalization. CONCLUSIONS: The use of transfusion can be improved by targeting use of blood to severely anemic children with cardiorespiratory compromise, improving immediate availability of blood, and treating severely anemic children with effective antimalarial therapy.

Adolescent↗
PubMed1996

Childhood mortality during and after hospitalization in western Kenya: effect of malaria treatment regimens.

Plasmodium falciparum infection is an important cause of the high childhood mortality rates in sub-Saharan Africa. Increasingly, the contribution of P. falciparum-associated severe anemia to pediatric mortality is being recognized while the impact of chloroquine resistance on mortality has not been evaluated. To address the issues of pediatric mortality, causes of death among hospitalized children less than five years of age in western Kenya were identified using standardized clinical examinations and laboratory evaluations. Follow-up examinations were conducted to determine the child's clinical status posthospitalization. Of the 1,223 children admitted to Siaya District Hospital from March to September 1991, 293 (24%) were severely anemic (hemoglobin level < 5.0 g/dL). There were 265 (22%) deaths; 121 (10%) occurred in-hospital and 144 (13%) occurred out-of-hospital within eight weeks after admission; 32% of all deaths were associated with malaria. Treatment for malaria with chloroquine was associated with a 33% case fatality rate compared with 11% for children treated with more effective regimens (pyrimethamine/sulfa, quinine, or trimethoprim/sulfamethoxazole for five days). The risk of dying was associated with younger age (P < 0.0001) and severe anemia (relative risk [RR] = 1.52, 95% confidence interval [CI] = 1.22, 1.90), and was decreased by treatment with an effective antimalarial drug (RR = 0.33, 95% CI = 0.19, 0.65). Effective drug therapy for P. falciparum with regimens that are parasitocidal in areas with a high prevalence of severe anemia and chloroquine resistance can significantly improve the survival of children in Africa.

Age Factors↗
PubMed1995

Severe illness in African children with diarrhoea: implications for case management strategies.

To identify clinical disorders associated with severe illness in African children with diarrhoea, we studied a group of under-5-year-olds with diarrhoea who had been brought to a large public hospital in central Cote d'Ivoire. The general condition of children with diarrhoea was assessed and classified according to criteria recommended by WHO, and then used as a nonspecific indicator of severity. Of the 264 children with diarrhoea who were enrolled in the study, 196 had nonsevere illness and 68 severe illness. Children with severe illness were significantly more likely than those with nonsevere illness to be dehydrated (45% versus 11%), moderate-to-severely wasted (47% versus 29%), bacteraemic (26% versus 9%), severely anaemic (haemoglobin level <6 g/dl; 15% versus 6%), have Plasmodium falciparum parasitaemia (27% versus 14%), and have two or more of these five conditions (60% versus 14%). Nontyphoidal Salmonella spp. were present in 68% of the blood isolates but were not associated with seropositivity to human immunodeficiency virus (HIV). The study demonstrates the need for a more comprehensive approach to assessment and management of children with diarrhoea that ensures prompt recognition of bacteraemia, anaemia, wasting and malaria, as well as dehydration. Simple nonspecific observational criteria, such as those recommended by WHO for assessing and classifying general condition, are useful for identifying children with diarrhoea who are at high risk of having life-threatening clinical disorders, and can readily be used by health workers whose clinical training and access to diagnostic laboratory facilities are both limited.

Case Management↗
PubMed1994

Clinical signs of pneumonia in children attending a hospital outpatient department in Lesotho.

To determine the value of clinical findings for the diagnosis of pneumonia, we evaluated 950 children who presented with respiratory illness to the outpatient department of the Queen Elizabeth II Hospital, Maseru, Lesotho. Those children at high risk for pneumonia and a systematically selected 20% sample of children at low risk were examined in turn by a nurse, a general practitioner, and a paediatrician; a chest radiograph was recorded for each child. Pneumonia was defined as radiographic findings compatible with the disease as interpreted by a paediatric radiologist. A respiratory rate > or = 50 breaths/minute was a sensitive sign for pneumonia among infants (sensitivity range for the three examiners: 59-79%), but identified a progressively smaller proportion of children with pneumonia in older age groups. Adjusting the respiratory rate for age using a threshold of > or = 40 breaths/minute for children aged > or = 12 months improved the sensitivity, but identified < 30% of children with pneumonia aged > or = 24 months. No drop in sensitivity with age was found when respiratory rate thresholds were evaluated for children with more severe radiographic evidence of pneumonia.

Age Factors↗
PubMed1992

Usefulness of clinical case-definitions in guiding therapy for African children with malaria or pneumonia.

The World Health Organisation has developed disease-specific clinical case-definitions to guide management of children with fever or cough, the cardinal signs of malaria and pneumonia. To assess the usefulness of the case-definitions and to investigate their interaction, we studied children with fever or cough brought to a hospital in Lilongwe, Malawi. For all children, a thick blood smear was examined for Plasmodium falciparum parasites. Chest radiography was done only for children with parasitaemia and those who satisfied the clinical case-definition for pneumonia; others were assumed to have normal chest radiographs. Of 1599 enrolled children, 566 (35%) had parasitaemia and 116 had radiographic evidence of pneumonia; 43 had both pneumonia and parasitaemia. Of the 471 children who met the clinical definition for pneumonia, 449 (95%) also met the malaria clinical definition. Among children with radiographic evidence of pneumonia, the clinical definition for malaria was not predictive of parasitaemia (sensitivity 93%, specificity 5%). Whether malaria parasitaemia was present or absent, the pneumonia clinical definition distinguished children with and without radiographic evidence of pneumonia (sensitivity and specificity > 60%). Children who satisfied the pneumonia clinical definition were more likely to have radiographic evidence of pneumonia (odds ratio 10.4, 95% confidence interval 5.2-20.7), parasitaemia (1.6, 1.2-2.2), or both at the same time (4.2, 2.1-8.4) than were children who did not meet the definition. Children who satisfy the malaria and pneumonia clinical definitions need treatment for both disorders. Scarce diagnostic methods, especially microscopy, are needed for more specific treatment of children with fever and cough.

Algorithms↗
PubMed1989

Hypochlorite sensitivity in man.

Observation of an individual with immediate-type reaction following exaggerated dermal exposure to hypochlorite-containing cleaning products prompted review of similar hypersensitivity reactions attributed to hypochlorite or other highly reactive chemicals. This review confirms isolated incidences of hypochlorite sensitivity of the delayed type (allergic contact dermatitis), as well as immediate-type reactions from inhalation or topical challenge of sensitized individuals. We conclude that it is possible that excessive and prolonged exposure to hypochlorite may in some cases result in irritation and damage to the skin. This potentially gives rise to altered proteins which in rare cases may cause hypersensitivity. This reaction is common to other reactive small molecules with a strong irritant action.

Adult↗
PubMed1987

Recent investigations of mechanisms of chemically induced skin irritation in laboratory mice.

The time course, dose response, components of inflammation, and involvement of putative mediators of inflammation in irritation induced by different chemicals was compared using a mouse ear swelling technique. Differences in time courses of inflammation produced by the irritants were not solely due to differences in rates of penetration. Changes in blood flow and permeability of vessels were phasic with different numbers of phases induced by different irritants. Effects of antagonist, synthesis, inhibitors, and depleting agents of putative inflammatory mediators on intensity of inflammation varied for different irritants. These studies demonstrate that all chemicals do not produce skin irritation by a common inflammatory pathway.

Alkynes↗
PubMed1985

Mechanisms of chemically induced skin irritation. I. Studies of time course, dose response, and components of inflammation in the laboratory mouse.

The possibility that chemicals induce skin irritation by multiple mechanisms was studied in laboratory mice. The time course and dose response to topical application of phenol, croton oil, benzalkonium chloride, ethyl phenylpropiolate (EPP), and methyl salicylate were compared. The responses to each chemical were measured as changes in ear thickness following application to one ear. Maximal responses were as follows: methyl salicylate 20 min, phenol 1 hr, croton oil and benzalkonium chloride 6 hr, and EPP 8 hr. The response to EPP included an early, smaller response at 1 hr. Time courses of the responses were not altered by changing the vehicle in which the irritants were applied or by altering the dose. The rates of regression of the inflammatory responses also varied. Although visibly normal, thickness of ears treated with either phenol or benzalkonium chloride remained 0.05 to 1 mm thicker than solvent-treated control ears for 6 weeks. Although the incidence of prolonged thickness was dose related, it was not determined by the intensity of the acute response; doses of other irritants which produced equivalent acute increases in ear thickness did not produce similar changes. The components of the acute responses, i.e., vascular permeability, change in blood flow, and cellular infiltration, to 5 mg methyl salicylate, 2 mg EPP, and 0.05 mg croton oil were compared in studies of tissue histology, changes in vascular permeability by trypan blue and 125I-labeled bovine serum albumin, and change in local surface temperature as an index of blood flow. The histology of the reactions at the time of maximum response to the chemicals differed. Multiple periods of increased permeability and increased surface temperature were produced by the irritants. The permeability and blood flow responses produced by the irritants varied in number, time of occurrence relative to time of application and to time of maximum response, and in magnitude of the changes. Differences in time courses of the responses which were not altered by experimentally varying rate of absorption and in components of the inflammatory response to the three irritants suggest that chemicals induce skin irritation by multiple mechanisms.

Absorption↗
PubMed1971

Fitness to fly?

Explore the source record for details and available documents.

Aerospace Medicine↗
PubMedDate not supplied

Comparison of the clinical and radiographic diagnosis of paediatric pneumonia.

Pneumonia causes 3.2 million deaths per year in children under 5 years old according to the World Health Organization. In spite of the number of deaths, no single clinical or radiological definition for the diagnosis of pneumonia is widely accepted. To determine the extent of agreement between clinical and radiographic diagnoses of pneumonia, we compared the clinical diagnoses made by an experienced paediatrician with diagnoses based on a paediatric radiologist's interpretation of chest radiographs. In 226 children with respiratory illness brought to a hospital outpatient department in Lesotho, pneumonia was the clinical diagnosis for 39 and the radiographic diagnosis for 40; however, for only 19 children did the 2 diagnoses concur. Children with a radiographic diagnosis of pneumonia tended to have been ill longer, to be older, and to be more likely to have a technically adequate radiograph than children with negative radiographs, independent of the clinical diagnosis. In this comparison, radiographic and clinical diagnoses for pneumonia differed substantially. Some of this discrepancy may be explained by misinterpretation of suboptimal films and different rates of evolution of radiographic and clinical manifestations of pneumonia. Radiographic studies and clinical evaluations produced complementary data in this evaluation: of the 60 children with clinical or radiographic evidence of pneumonia, 14 would not have been treated with an antimicrobial drug without radiography. Wider availability of radiography is needed to supplement clinical examination for the diagnosis of pneumonia, and may be particularly valuable in children more than 18 months old, those who have been ill for more than 6 d, and those with fever.

Female↗
PubMedDate not supplied

Depigmentation with tert-butyl hydroquinone using black guinea pigs.

tert-Butyl hydroquinone (TBHQ) has important and functional uses in consumer and commercial applications, some of which involve human exposure primarily through dermal contact. To assist in the safety evaluation of TBHQ, this study was conducted to determine whether TBHQ would produce changes in skin pigmentation after repeated dermal application to black guinea pigs. Hydroquinone (HQ) and hydroquinone monomethyl ether (HQMME) were used as positive controls. TBHQ and HQ were tested at concentrations of 0.1, 1.0 and 5.0%, while HQMME was tested at a concentration of 10.0%. Groups of five males and five females were dosed with TBHQ, HQ, or the vehicle (hydrophilic ointment) daily (M-F) for 13 weeks. In addition, animals (five males, five females) treated with HQMME received 13 doses over a 3-week period. The application site was evaluated weekly for degree of pigmentation loss and irritation. Twenty-four hours after final application, sites were evaluated for depigmentation, irritation and hyperpigmentation. Subsequently, the application site was depilated and re-evaluated for the same endpoints. Repetitive exposure to concentrations of 1.0% and 5.0% TBHQ and HQ were slightly to moderately irritating, while 0.1% of each of these test materials produced only weak irritant responses. No irritant responses to hydrophilic ointment were observed and HQMME produced weak irritant responses after 2 weeks. Neither 0.1% TBHQ nor HQ produced depigmentation, while 20% of animals dosed with 1.0% TBHQ and 30% of animals dosed with 1.0% HQ had spotty or uniform loss of pigment at the site of treatment. Approximately 40% of animals dosed with 5% TBHQ or HQ were depigmented at the treatment site at the final evaluation. HQMME produced complete depigmentation of the skin and hair in all animals. Hyperpigmentation of the treatment site was observed in 80-100% of animals in all groups (with the exception of HQMME-treated animals, treated for only 3 weeks), which may be attributable to the use of hydrophilic ointment as the vehicle, the application procedure, or simply clipping hair from the skin. Thus, this study showed that TBHQ causes depigmentation in black guinea pigs at concentrations of 1% or greater, but that a no-effect threshold for this endpoint exists at a concentration between 0.1 and 1.0%.

Administration, Cutaneous↗
PubMedDate not supplied

Atypical pseudoaneurysm after mitral valve replacement: Doppler echocardiographic diagnosis.

Ventricular pseudoaneurysm is a rare complication of mitral valve replacement or myocardial infarction. Typically, a ventricular pseudoaneurysm appears as an echocardiographic lucency posterior and lateral to the left ventricle and is best seen from the parasternal long axis and apical four-chamber views. We present an atypical case of left ventricular pseudoaneurysm that tracts posterior and lateral to the right ventricle that was best visualized from the subcostal and low parasternal windows with medial angulation. Doppler imaging confirmed the diagnosis by demonstrating to-and-fro flow between the left ventricle and the cavity located behind the right ventricle. This case emphasizes the importance of the use of multiple echocardiographic windows.

Aged↗