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PubMed1980

[Ergometric investigations of the tension-time-index and of the PWC 170 in patients with borderline and stable hypertension in comparison with normals (author's transl)].

1. Comparative measurements of the Tension-Time-Index during ergometric work and of the Physical Working Capacity 170 were carried out in patients with borderline (n = 24) and stable hypertension (n = 51) in comparison with normals (n = 47), aged 20-60 years. 2. The Tension-Time-Index which is generally accepted as an indirect estimation of the myocardial oxygen consumption was significantly (p < 0.001) higher in the borderline hypertensives (30.5%) and in the hypertensives (41.7%) already at the low work load of 50 watt. 3. The PWC170 which has been shown to be a reliable ergometric method for determination of the physical performance was 21.2% lower (p < 0.001) in the hypertensives with 2.71 +/- 0.74 W/kg body weight in comparison with 3.44 +/- 0.8 W/kg body weight of the normals. Already the borderline hypertensives had a reduced PWC170 of 2.93 +/- 0.7 W/kg body weight. 4. Therefore hypertensives should perform a dosed endurance training of middle intensity, which results in a reduction of heart rate, systolic blood pressure and consequently of the Tension-Time-Index and which improves the Physical Working Capacity. These favourable effects of training are of great benefit especially for those patients also suffering from ischemic heart disease because the myocardial oxygen consumption is the limiting factor of physical performance. 5. In order to prevent acute and chronic vascular complications caused by excessive blood pressure increases during physical activity in hypertensives, ergometric tests for dosage of training and if necessary an antihypertensive treatment should be applied before starting the training program.

Adult↗
PubMed2006

Association of interferon gamma T+874A and interleukin 12 p40 promoter CTCTAA/GC polymorphism with the need for respiratory support and perinatal complications in low birthweight neonates.

BACKGROUND: Data support the role of interferon (IFN)gamma and interleukin (IL)12 in perinatal complications. IFNgamma T(+874)A and IL12 p40 promoter CTCTAA/GC polymorphisms may have an effect on cytokine production. METHODS: DNA was extracted from dried blood samples of 153 low birthweight (LBW) infants and 172 healthy term infants. IFNgamma and IL12 genetic polymorphisms were determined to investigate the association between polymorphisms and ventilation characteristics, bronchopulmonary dysplasia (BPD) and other perinatal disorders. RESULTS: The IFNgamma(+874)A allele was over-represented in LBW infants. Carriers of the IFNgamma(+874)T allele required mechanical ventilation and oxygen supplementation for time periods 41% and 35%, respectively, shorter than those required by those not carrying the IFNgamma(+874)T allele. Stepwise logistic regression analysis showed that carriers of the IFNgamma(+874)T allele were protected against BPD (odds ratio (OR) 0.35 (95% confidence interval (CI) (0.12 to 0.99))) and patent ductus arteriosus (OR 0.43 (95% CI 0.19 to 0.97)), whereas carriers of the IFNgamma(+874)A allele were at higher risk of severe hypotension (OR 3.40 (95% CI 1.01 to 11.52)) and respiratory distress syndrome (OR 4.03 (95% CI 1.30 to 12.50)). Carriers of the IL12 GC allele were protected against pneumonia (OR 0.32 (95% CI 0.14 to 0.75)). Carriers of the IL12 CTCTAA allele were at higher risk of developing necrotising enterocolitis (NEC; OR 2.37 (95% CI 1.01 to 5.53)). CONCLUSIONS: Carrier state of the IFNgamma(+874)A allele presents an increased risk for premature birth and lung damage, as well as other perinatal complications. The risks of pneumonia and NEC are higher in heterozygotic carriers of the IL12 CTCTAA/GC polymorphism. Further studies are needed to determine whether these associations are the result of altered cytokine-producing capacity in infants carrying the tested alleles.

Alleles↗
PubMedDate not supplied

[Cross-over epidemiologic study of symptoms and respiratory function in workers at a furniture factory].

An epidemiological survey on symptoms and diseases (collected with CNR standardized questionnaire) and on lung function (forced vital capacity and derived indexes; CO diffusing capacity) has been carried on in workers of a furniture plant in Arezzo. Significantly higher prevalence rates of cough in smokers than in non smokers, and of cough, phlegm, wheeze in non smoker workers than in the control group from a general population sample were present. A not significant relationship of symptoms and working years was also found. Lung function indices were in the normal range; smokers had significantly lower values than non smokers. A lower FEV1%, after adjusting for age and smoking, was shown by subjects with more working years. Thus, in a modern furniture plant the risk of adverse health effect seems to be slight: this conclusion may be confirmed by the ongoing longitudinal survey.

Adult↗
PubMed1978

Pulmonary function studies in sickle cell anaemia.

Pulmonary studies including the measurements of single-breath diffusing capacity for carbon monoxide (DL); Forced Vital Capacity (FVC); Residual Volume (RV) and Total Lung Capacity (TLC) were carried out in forty normal subjects; twelve patients with homozygous sickle cell anaemia and five patients with iron deficiency anaemia due to hookworm infestation. Normal subjects had a mean haemoglobin content of 13.4 g per 100 ml and a mean DL value of 28 ml/min/mmHg. In the patients with hookworm anaemia, the mean haemoglobin was 4.9 g per 100 ml while the mean DL value was 9 ml/min per mmHg. Patients with sickle cell anaemia had a mean haemoglobin content of 6.2 g/100 ml yet the mean DL value was 20 ml/min per mmHg. The study showed that patients with homozygous sickle cell anaemia have a disproportionately high DL value in the presence of severe anaemia which might be due to a chronically expanded pulmonary capillary blood volume as a compensatory mechanism to maintain an appropriate level of DL.

Adolescent↗
PubMed1987

Design and synthesis of a theophylline bonded-phase column for HPLC--application to separation of aromatic carboxylic acids.

A stationary phase has been designed and synthesized in which theophylline residues are covalently bonded to a silica support through an eight carbon hydrocarbon linkage. The phase offers improved resolution in the separation of aromatic carboxylic acids over that available with conventional reversed phase supports. The column is relatively stable. Retention can be modified by adjusting mobile phase composition with respect to pH, electrolyte type and concentration, and organic modifier as well as by manipulating the temperature at which chromatography is carried out. The capacity factors, k', for a series of ring substituted benzoic acids were correlated with the complexation constants previously reported for these compounds with theophylline in bulk phase solution.

Journal Article↗
PubMed2006

Fall-related injuries among initially 75- and 80-year old people during a 10-year follow-up.

The aim of this study was to investigate the occurrence, type, scene and seasonal variation of fall related injuries, and the impact of socio-economic factors, mobility limitation, and the most common diseases on the risk of injurious falls over a 10-year follow-up. Elderly residents of Jyväskylä, Finland, aged initially 75 and 80 years, took part in the study in 1989-1990. The health and functional capacity assessments were carried out at the baseline. Injurious falls were monitored over a 10-year period. The rate of injurious falls per thousand person-years was 188 among women and 78 among men. Of all fall-related diagnoses, head injuries comprised 32%, upper limb injuries 27% and hip injuries 19%. Majority of injurious falls took place indoors and no seasonal variation in fall occurrence was observed. Recurring falls were more likely to take place in institutions. Osteoarthritis increased the risk of injurious falls but no effect was observed for coronary heart diseases or mobility limitation. All in all, intrinsic factors, such as chronic diseases and mobility limitation had only minor effect on risk of injurious falls among older people. The current results suggest that preventive interventions for injurious falls among older people should pay attention to the risk factors present indoors.

Accidental Falls↗
PubMed2005

Hydrogen sulfide removal by compost biofiltration: effect of mixing the filter media on operational factors.

The overall goal of this work was to determine the effect of mixing the filter media of a compost biofilter on H(2)S removal efficiency. The behavior of important operational factors such as moisture of filter media, pressure drop and sulfate accumulation were evaluated, considering mixing the media. Additionally, tracer studies were performed in order to determine the effect of mixing the media on gas distribution. H(2)S removal capacity decreased over time, from 100% to 90%. When bed mixing was carried out, the removal capacity remained constant, close to 100%, and moisture content and sulfates accumulation were better controlled at 50% and at 12 mg S-SO(4)/g dry media respectively. In addition, under this operational pattern, an improvement in gas and particle size distribution was observed inside the filter media, fitting the axial dispersion model and the Ergun equation.

Air Pollutants↗
PubMed2006

Biomechanical study of a prosthetic solution based on an angled abutment: case of upper lateral incisor.

OBJECTIVES: To study the complex behaviour of an upper lateral incisor restoration using an angled abutment, a mechanical analysis of the abutment bearing capacity was firstly carried out. The evolution of bone properties around implant was then simulated as a function of time to estimate the maximal load that could be supported by the prosthetic solution without bone damage. MATERIALS AND METHODS: According to the Food and Drug Administration procedure, experimental tests were firstly carried out on five samples. A 25 degrees -angled abutment screwed to an implant embedded into a massive steel bloc was submitted to a static loading. Two finite element models were also built: the first one (I) to interpret and complete the results obtained in the experimental part and the second one (II) to simulate bone remodelling around implant considering a strain energy stimulus. RESULTS: According to experiments, the abutment straightening was observed for an average force of 869N. Numerical model (I) confirmed this result and indicated that the initial irreversible deformation (yielding) of abutment was obtained for a 283N compressive force. It could thus be deduced that this abutment can safely be used for an incisor restoration. Model (II) showed that, after 26 months, some of the cancellous bone initially present in an approximately one millimetre thick shell surrounding the implant had reached the density of cortical bone. A safe load notion corresponding to the force leading to the maximal admissible strain value for trabecular bone was introduced. It evolved from 44N after surgery to approximately 160N after 26 months.

Biomechanical Phenomena↗
PubMed1999

Adsorptive infiltration of metals in urban drainage--media characteristics

Urban pavement drainage often contains significant quantities of anthropogenic metal elements, including Cd, Cu, Pb and Zn that exceed surface water discharge standards. In many urban areas low rainfall pH, results in predominately dissolved metal element mass. Such partitioning has critical implications for the selection of in-situ treatment. One such category of treatment is engineered infiltration systems. To be effective, such systems must adsorb dissolved metal elements to their fixed media while also acting as filters for particulate-bound fractions. One such strategy is called a partial exfiltration trench (PET). The PET contains oxide-coated sand (OCS); an amphoteric media of high surface area (5-15 m2/g) as compared to uncoated silica sand (0.01-0.05 m2/g). OCS was generated through heating a mixture of silica sand and ferric nitrate solution to dryness. This paper presents results of both media characterization and bench scale PET simulations. Media tested were OCS and plain silica sand. Media testing was carried out until capacity was exhausted, using both synthetic and actual stormwater loadings. Testing was conducted for pH levels of 6.5 and 8.0. Results indicated that OCS had greater capacity than silica sand for all dissolved fractions. As the pH was raised from 6.5 to 8.0, OCS capacity was improved. A PET configuration with porous pavement resulted in the highest in-situ treatment capacity for metal element bearing storm water.

Journal Article↗
PubMed2003

Biodiesel production from waste cooking oil: 2. Economic assessment and sensitivity analysis.

The economic feasibilities of four continuous processes to produce biodiesel, including both alkali- and acid-catalyzed processes, using waste cooking oil and the 'standard' process using virgin vegetable oil as the raw material, were assessed. Although the alkali-catalyzed process using virgin vegetable oil had the lowest fixed capital cost, the acid-catalyzed process using waste cooking oil was more economically feasible overall, providing a lower total manufacturing cost, a more attractive after-tax rate of return and a lower biodiesel break-even price. On the basis of these economic calculations, sensitivity analyses for these processes were carried out. Plant capacity and prices of feedstock oils and biodiesel were found to be the most significant factors affecting the economic viability of biodiesel manufacture.

Biotechnology↗
PubMed1995

Prefabricated vascularized periosteal grafts using fascial flap transfers.

The purpose of this study was to demonstrate the feasibility of prefabricated vascularized periosteal grafts using fascial flap transfers. Fifty rats were divided into two (Group A, underwent periosteal wrapping, and Group B underwent fascial wrapping). Fascial flap from the medical leg, which were nourished by the saphenous artery and vein, were used for all grafts. In Group A, the fascia was transferred onto the proximal tibial periosteum. Two weeks postoperatively, the elevated fascioperiosteal flap was wrapped around a 4-mm hydroxapatite cube. In Group B, the fascial flap was immediately wrapped around the hydroxyapatite cube. In both groups, the hydroxapatite-wrapped cube was transferred to the inguinal region. Three days postoperatively, five rats from group A were sacrificed. On histologic examination, these five showed no necrosis of the fascioperiosteal flap and no bone formation. The remaining 45 rats were sacrificed 5 weeks postoperatively. Microangiography was performed on five rats in Group A, revealing neovascularization of the hydroxyapatite. On histologic examination, new bone formation was confirmed in 15 of the remaining 20 rats in Group A, and in three of the 20 rats in Group B. These experiments demonstrated that the prefabricated vascularized periosteal graft, which has good osteogenic capacity, could be carried out using a fascial flap transfer.

Angiography↗
PubMed2001

Impact of plasmapheresis on platelet hemostatic capacity in healthy voluntary blood donors detected by the platelet function analyzer PFA-100.

Previous flow cytometry studies showed that platelet activation may occur during cytapheresis, cardiopulmonary bypass and hemodialysis. The aim of this pilot study was to determine if the impact of plasmapheresis leads to alterations in platelet hemostatic capacity. Plasmapheresis was carried out in 30 volunteers using an Autopherese C (Baxter) and an MCS3p (Haemonetics). Blood samples were collected and analyzed immediately before and after plasmapheresis. As a result of the plasmapheresis on the Autopherese C, the mean closure time (CT) for collagen/epinephrine (Col/Epi) increased from 118.2 +/- 25.1 to 149.9 +/- 35.0 s and from 88.7 +/- 16.9 to 98.5 +/- 26.3 s for collagen/ADP (Col/ADP), respectively. Seven subjects showed impaired CTs after plasmapheresis for Col/Epi. For Col/ADP, five subjects showed impaired CTs after apheresis. Statistical analysis (McNemar test) showed a significant difference before and after apheresis for Col/Epi (P = 0.024) but not for Col/ADP (P = 0.088). Similar results were shown for plasmapheresis carried out with the MCS3p. These findings show that plasmapheresis can cause an impairment of platelet function in healthy volunteers as measured by the PFA-100, an effect of so far unknown clinical significance.

Adult↗
PubMed1999

Transmission of a Y chromosomal deletion involving the deleted in azoospermia (DAZ) and chromodomain (CDY1) genes from father to son through intracytoplasmic sperm injection: case report.

The transmission of a deleted in azoospermia (DAZ) deletion from a severely oligozoospermic patient to his son following intracytoplasmic sperm injection (ICSI) treatment is reported. The case report highlights the fertilizing capacity of spermatozoa carrying Y chromosome deletions in patients treated with ICSI and stresses the importance of genetic counselling in severe male infertility.

Adult↗
PubMed1998

Ability of clinical isolates of group A streptococci to adhere to and invade HEp-2 epithelial cells.

Individual strains of group A streptococci (GAS) differ in virulence, but the reasons for these differences are incompletely understood. To determine if the ability of GAS to cause invasive disease corresponded with their capacity to adhere to or invade epithelial cells, 63 clinical isolates of GAS (40 from patients with systemic infection and 23 from superficial disease) were examined in quantitative assays of bacterial adhesion to and invasion of HEp-2 cells, a continuous line of human pharyngeal epithelial cells. The results showed that individual isolates of GAS varied considerably in their ability to adhere to and penetrate HEp-2 cells. However, on the whole, strains from patients with invasive disease adhered to cells in numbers c.1.5 greater than those from superficial infection. Paradoxically, strains from patients with invasive disease invaded HEp-2 cells to a significantly lesser extent than those from superficial sites, with a two-fold difference in invasion index (defined as the percentage of cell-associated bacteria located intracellularly). To determine if these differences were caused by differences in the production of hyaluronic acid capsule or M protein by the two groups of bacteria, the adherence and invasive capacities of bacteria carrying defined mutations in the genes for these factors were examined. Although M6-protein-deficient [corrected] bacteria were less adherent to HEp-2 cells than the wild-type, neither the hyaluronic acid capsule nor the M protein had a significant influence on the ability of GAS to adhere to or invade HEp-2 cells. The results of this study demonstrate that there are biological differences between GAS isolates associated with invasive and superficial diseases and that these differences can be demonstrated by an assay of bacterial adherence to and invasion of HEp-2 epithelial cells.

Adult↗
PubMed2005

Coercion or collaboration? Nurses doing research with people who have severe mental health problems.

Nurses should address the concerns of service users in research and engage in collaborative work with them. Doing this presents ethical dilemmas, not least around the issues of assessing capacity and informed consent to participation in research. The view that judgement regarding the capacity to consent is solely the responsibility of a consultant psychiatrist is challenged as inadequate. The concept of 'moral discourse' (Pike 1991) is used to understand the process by which the assessment of capacity may be carried out. This is illustrated by the application of the concept in a qualitative research study carried out to explore what makes mental health services accessible to women with children. The role of the mental health nurse entails surveillance and the development of expertise in negotiating compliance with treatment programmes. The paper outlines the measures taken to ensure that service users felt empowered, rather than coerced, to participate in this study. While Community Mental Health Team workers were engaged in 'moral discourse' in respect of participation by service users in the study, there were difficulties in engaging General Practitioners. However, there was evidence that women themselves felt empowered both to express interest in participating and to withdraw if they so wished.

Coercion↗
PubMed1978

Inhibition of MLC responder and stimulator function with allo-antisera in rhesus monkeys.

Ten antisera containing antibodies directed against specificities controlled by the Ia1 locus of rhesus monkeys were tested for their ability to inhibit the MLC reaction. In cultures with responding cells from the serum producer, all sera with anti-Ia1 activity depressed the stimulatory capacity of cells carrying the Ia1 antigen in question. In other responder/stimulator combinations, the stimulation-inhibition was Ia1-related for the majority of the antisera. These data provide further evidence for a possible identity (or close association on the cell membrane) between Ia1 and D locus determinants of rhesus monkeys. In addition, some sera showed an inhibitory effect also on responder cells (with cells from the serum producer as stimulators). There was no apparent relation of response inhibition to the Ia1 specificities detected by antisera.

Animals↗
PubMed1987

Nucleotide sequence of the uhp region of Escherichia coli.

The Escherichia coli uhp region encodes the transport system that mediates the uptake of a number of sugar phosphates as well as the regulatory components that are responsible for induction of this transport system by external glucose 6-phosphate. Four uhp genes have been identified by analysis of the complementation behavior and polypeptide coding capacity of plasmids carrying subcloned regions or transposon insertions. The nucleotide sequence of a 6.5-kilobase segment that contains the 3' end of the ilvBN operon and the entire uhp region was determined. Four open reading frames were identified in the locations expected for the various uhp genes; all were oriented in the same direction, counterclockwise relative to the genetic map. The properties of the polypeptides predicted from the nucleotide sequence were consistent with their observed features. The 196-amino-acid UhpA polypeptide has the composition characteristic of a soluble protein and bears homology to the DNA-binding regions of many regulatory activators and repressors. The 518-amino-acid UhpB and the 199-amino-acid UhpC regulatory proteins contain substantial segments of hydrophobic character. Similarly, the 463-amino-acid UhpT transporter is a hydrophobic protein with numerous potential transmembrane segments. The UhpC regulatory protein has substantial sequence homology to part of UhpT, suggesting that this regulatory protein might have evolved by duplication of the gene for the transporter and that its role in transmembrane signaling may involve sugar-phosphate-binding sites and transmembrane orientations similar to those of the transport protein.

Amino Acid Sequence↗
PubMed1992

Palatopharyngoglossoplasty in the treatment of patients with obstructive sleep apnea syndrome.

A new technique (palatopharyngoglossoplasty (PPGP)) has been developed for surgical treatment of patients with the obstructive sleep apnea syndrome (OSAS). In 20 operated patients 18 reported immediate marked improvement of daytime sleepiness, alertness and vigilance during the day, and of working capacity. However, polysomnography carried out pre- and postoperatively showed that only 10 patients were "cured", defined as 50% or more reduction in apnea/hypopnea index (AHI). Cephalometric analysis pre- and postoperatively indicated that nonresponders had a long and narrow posterior airway space, and we suggest that during sleep this part of the upper airway collapses before as well as after the operation. The discrepancy between the subjective improvement observed after PPGP and the postoperative reduction in AHI may be due to reduced/eliminated snoring and/or improvement in sleep quality after the operation.

Adult↗