Respiratory illness and home environment of ethnic groups

Factors contributing to differences in the prevalences of respiratory symptoms and diseases among ethnic groups were studied in primary schoolchildren living in 20 inner city areas of England in 1983. The raised prevalences of respiratory symptoms in these groups were compared with results from a national representative sample of children studied in 1982. Data on age, sex, respiratory illness, and social and environmental variables were obtained by questionnaire for 4815 children living in inner cities. The children were classified as white, Afro-Caribbean, Urdu, Gujarati, Punjabi, other Asian, or "other." Significant differences in the prevalence of respiratory conditions were found among the ethnic groups after allowance was made for the effects of interfering variables. Except for asthma all conditions were most prevalent in Afro-Caribbeans and whites. In these two ethnic groups respiratory illness was significantly associated with belonging to a one parent family and the combined use of gas cookers and paraffin heaters at home. Respiratory illness was found to vary in prevalence among ethnic groups but may be perceived differently by different groups. Further studies, measuring lung function, are necessary.     

The association of hepatitis A and Helicobacter pylori with sensitization to common allergens, asthma and hay fever in a population of young British adults

BACKGROUND: A negative association of oro-faecally spread infection with serological markers of sensitization and allergic disease has been reported. METHOD: Previous infection with hepatitis A and Helicobacter pylori was assessed in a community-based sample of young British adults and associations with serum-specific IgE to environmental allergens, asthma-like symptoms and hay fever were examined. RESULTS: There was no association of previous infection with hepatitis A or H. pylori with wheeze or hay fever. There was no evidence of an association of infection with either agent and sensitization except for the isolated finding of a lower prevalence of sensitization to grass in those with IgG antibodies to H. pylori (OR 0.65, 95% CI 0.43-0.99). This association did not explain the negative association of family size with sensitization to grass. CONCLUSION: In this population, there was no evidence that infection with hepatitis A or H. pylori was associated with lower levels of IgE sensitization, asthma or hay fever except for an isolated finding of a negative association of H. pylori infection with sensitization to grass.     

A randomized controlled trial of an information booklet for hypertensive patients in general practice

A randomized controlled trial of an information and medical record booklet designed to improve patient understanding and participation in the management of hypertension was conducted in six inner London general practices. After one year there were no significant differences between the group who had received the booklets and the control group in mean systolic or diastolic blood pressure, but the study group scored significantly higher on knowledge about hypertension and its management. However, the difference between the two groups was small, possibly because both groups started with a high level of understanding about hypertension and its management. In addition, the mean diastolic blood pressure in the control group showed that the treatment provided was already satisfactory, and that there was little need for improvement. Nevertheless, the information booklet evaluated in this study provides health professionals with a highly acceptable method of informing the patient about hypertension and its management and could be used both in hospital and general practice.     

Laboratory preparation of plasticware to support cell culture

Summary Many plastics, including polystyrene and poly(ethylene terephthalate), are unsuitable for cell culture applications as formed because they do not support cell growth. Although cells may attach to these materials, the attached cells typically round up and detach or die after a short time. However, plastics can be made to support normal cell attachment and growth through surface modification by glow discharge processes that produce ionized gas species which react with the surface of the plastic. This article describes radiofrequency glow discharge (RFGD) modification of plastics in the presence of organic vapors such as acetone, methanol and ethylene oxide. These treatments render laboratory plastics amenable to in vitro cell culture. Successful modification is a function of RFGD reaction parameters (position within the reactor, discharge power, system pressure, flow rate, and reaction time), and can be confirmed by electron spectroscopy for chemical analysis (ESCA). Identification by high resolution ESCA of functional groups introduced onto the surface by the RFGD process can be used to correlate cell growth with surface chemistry. A brief discussion of other processes thought to be used for preparation of commercial tissue culture ware is also provided.     

Reticulate bodies as single antigen in Chlamydia trachomatis serology with microimmunofluorescence.

Formalin-fixed, purified reticulate bodies (RB) of Chlamydia trachomatis immunotype C/TW-3/OT were used as a serological test antigen in the microimmunofluorescence test. The sensitivity and specificity of the RB antigen were compared to elementary bodies (EB) used as antigens in the detection of C. trachomatis antibodies in human sera by microimmunofluorescence. RB reacted with all known C. trachomatis immunotypes with the same sensitivity as the homotypic EB. In routine serology with sera and endocervical secretions, the RB antigen had a sensitivity similar to that of the EB in detecting serum antibodies, endocervical secretion antibodies, and antibodies of immunoglobulin M and G classes. No false-positive reactions were detected with control sera. All positive reactions showed type-specific antibodies against an EB immunotype. RB seemed to demonstrate chlamydial group reactivity; sera from 10 psittacosis patients diagnosed clinically and serologically by complement fixation showed five positive, three equivocal, and two negative reactions. By immunofluorescence, RB appeared as distinct rings demonstrating uniform peripheral surface fluorescence at their rims. The EB appeared as pinpoint-sized dots. C/TW-3/OT RB used as a single test anitgen should provide a simple and sensitive serological assay for the detection of C. trachomatis antibody.     

Force enhancement by PEG during ramp stretches of skeletal muscle

We have investigated the effects of a stronger actomyosin bond on force (Ps) during rapid stretch of active permeabilized rabbit psoas muscle fibers as a function of temperature from 5 to 30 degrees C. The strength of the actomyosin bond is enhanced by addition of polyethylene glycol (PEG), especially in pre-powerstroke states [Chinn et al. (2000) Biophys J 49: 437-451]. We have hypothesized that such states produce much of the force when activated muscles are stretched [Getz et al. (1998) Biophys J 75: 2971-2983]. Addition of PEG to activated fibers produced a small increase in isometric tension, Po (50-90 kN/m2), which was approximately independent of temperature. In contrast PEG produced a dramatic increase in Ps at low temperatures (200-300 kN/m2), but a modest increase at higher temperatures (70-90 kN/m2). We also measured Ps and Po in solutions containing the phosphate analog aluminum fluoride (AlF4) with and without PEG. In the absence of PEG, AlF4 reduced Po much more than Ps. Addition of PEG did not enhance Po, but enhanced Ps significantly. The contrasting effects of PEG on Ps and Po, and the effect of temperature can be explained by a model in which stretch force is produced by pre-powerstroke cross-bridges whose maximum distension is increased by PEG, and isometric force is produced by strongly bound cross-bridges whose bond strength is also enhanced by PEG, but to a lesser extent.     

Adsorption of baboon fibrinogen and the adhesion of platelets to a thin film polymer deposited by radio-frequency glow discharge of allylamine.

Platelet adhesion under static and flow conditions from a washed platelet suspension containing albumin to a polymer deposited by radio-frequency glow discharge of allylamine vapour on a poly(ethylene terephthalate) substrate was measured. Electron spectroscopy for chemical analysis was used to characterize the surface. Fibrinogen adsorption from a series of dilute plasma solutions to radio-frequency glow discharge/allylamine, measured using 125I radiolabelled baboon fibrinogen, increased with decreasing plasma dilution to a level much higher than that previously observed on polyurethanes. Elutability by sodium dodecyl sulphate of fibrinogen adsorbed from dilute plasma also increased with increasing plasma concentration, but fibrinogen preadsorbed from plasma became non-elutable when surfaces were stored in buffer for 5 d before contact with sodium dodecyl sulphate. Platelet adhesion to substrates which had been pre-adsorbed with dilute plasma was measured using baboon platelets radiolabelled with 111In. Adhesion greatly decreased as the plasma concentration used for preadsorption increased, suggesting that non-specific platelet binding to the bare surface occurs when protein coverage is incomplete. Non-specific platelet binding was inhibited to varying degrees by preadsorption of different proteins to the surface. Platelet adhesion to surfaces preadsorbed with dilute (1.0%) baboon and human plasmas lacking fibrinogen (i.e. serum, heat-defibrinogenated plasma and congenitally afibrinogenemic plasma) was diminished compared with normal plasma. Addition of exogenous fibrinogen to the deficient plasma partially restored platelet adhesion to normal levels. Adhesion to surfaces preadsorbed with human plasma deficient in von Willebrand factor was comparable to that observed with normal plasma. The plasma preadsorption studies with fibrinogen deficient media suggested that adsorbed fibrinogen is necessary for platelet adhesion to the radio-frequency glow discharge/allylamine substrate at high protein coverage. However, since adhesion was greatly reduced when the plasma preadsorbed substrate was stored in buffer before platelet contact, the conformation of adsorbed fibrinogen is also important in mediating platelet adhesion to radio-frequency glow discharge.     

Diagnostic tests in the evaluation of dementia. A prospective study of 200 elderly outpatients

We studied the components of the diagnostic evaluation in 200 patients older than 60 years of age with suspected dementia who received standardized diagnostic evaluation and follow-up. The most common dementia diagnoses were Alzheimer's-type dementia (74.5%) and dementia due to toxic effects of drugs (9.5%). Eleven patients with hypothyroidism, metabolic encephalopathies due to hyponatremia, hyperparathyroidism, and hypoglycemia required laboratory tests for diagnosis, whereas the other dementia diagnoses were made primarily on the basis of data available on the history and physical and neurologic examinations. The complete blood cell count, blood chemistry battery (especially sodium, calcium, and glucose concentrations), and thyroid function tests were of definite value for the diagnosis of unsuspected disease and were useful as routine tests in evaluating patients for dementia. A careful history and physical examination accompanied by complete blood cell count, chemistry battery, and a thyroid function test would have been effective in diagnosing treatable illnesses causing cognitive impairment. Other diagnostic tests could have been used selectively based on results of the examination and screening tests. Estimated diagnostic charges from a selective approach would be 25% to 34% of those for the "routine" evaluation.     

Needle biopsy of renal allografts: comparison of two techniques

Two techniques for renal allograft biopsy were retrospectively evaluated to compare relative safety and efficacy. After ultrasound (US) localization of the kidney and biopsy with a hand-held 14-gauge cutting needle, an adequate specimen was obtained in 74 of 77 cases (96%). Major complications occurred in six of these 77 cases (8%). One hundred four biopsies were performed by using a smaller 18-gauge cutting needle with a spring-loaded biopsy "gun" and real-time US guidance. With this newer technique, specimens adequate for diagnosis were obtained in 99 biopsies (95%). There was a single major complication with this technique (1%). The 18-gauge needle with real-time US guidance yields comparably adequate specimens with a lower frequency of complications.     

分娩期连续电子胎心监护用于胎儿评估

1背景 在美国，每4例孕妇中有3例在产群中及分娩时使用电子胎儿监护（EFM）（NCHS1993）。1989年，美国妇产科学院（ACOG1989）发表了一项声明，对于低危妊娠既可使用EFM，也可使用间断性胎心听诊；但是，美国预防保健委员会（USPSTF1989）和加拿大的定期健康检查委员会（CTFPHE1994）对高危妊娠仍保留使用EFM。尽管有人对EFM的效果和安全性表示担忧（Thacker 1987：Thacker 1995），