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PubMed2002

Microscopic haematuria in giant cell arteritis.

Giant cell arteritis (GCA) is traditionally considered to spare the kidney, although an uncontrolled study reported microscopic haematuria in 10 out of 30 patients with GCA. To study the frequency and the characteristics of microscopic haematuria in GCA, we retrospectively studied 42 patients with biopsy-proven GCA, 39 patients with polymyalgia rheumatica (PMR) and 62 control patients >or=60 years of age, admitted to the general internal medicine unit. Patients with pyuria, significant bacteriuria or a known haematuric disorder were excluded. Microscopic haematuria was defined as the presence of >5 red blood cells (RBC) per high-power field (sediment counts) or of >8 RBC/microl (direct counting). Microscopic haematuria was present at presentation in 47.6% of the GCA patients, versus 17.9% of the PMR patients (P = 0.005) and 21.0% of the control patients (P = 0.008). Urinary RBC were predominantly dysmorphic in all GCA patients in whom RBC morphology was assessed (n = 7). Presenting symptoms, renal function, arterial blood pressure and degree of leukocyturia did not differ significantly between GCA patients with or without haematuria. After the initiation of corticosteroid therapy, microscopic haematuria was no longer detectable in 25 of 35 GCA patients (71.4%). Microscopic haematuria of renal origin is frequent but generally benign in patients with GCA. Its presence, if unassociated with blood pressure elevation or renal function deterioration, helps to rule in rather than to rule out the diagnosis of GCA. In the typical setting invasive urologic and nephrologic work-up may not be warranted.

Age Distribution↗

PubMed2003

Respiratory disease due to parainfluenza virus in adult leukemia patients.

Reports of human parainfluenza viruses (HPIV) in patients with leukemia have been limited to a few cases or as a portion of general surveys. In order to expand the knowledge of these infections in this patient group, the frequency and clinical course of HPIV infections was determined among 1,787 patients with leukemia treated at The University of Texas M.D. Anderson Cancer Center between July 1994 and December 1997. HPIV was isolated from 47 (6.2%) of the 770 patients who were cultured for respiratory viruses. HPIV type 3 accounted for 39 of the 47 HPIV infections. Twenty-six patients developed pneumonia, and the associated mortality was 27%. Multivariate analysis revealed that a low absolute lymphocyte count and pneumonia were associated with increased mortality. Concurrent respiratory and other infections were associated with an increased frequency of pneumonia. Only five patients with pneumonia received antiviral therapy and four of them survived the infection. HPIV infection in leukemic patients is frequently associated with pneumonia and the mortality rate from pneumonia is substantial among lymphopenic patients.

Adolescent↗

PubMed2003

Incidence and risk factors for nosocomial infections caused by fluoroquinolone-resistant Escherichia coli.

The aim of the retrospective case-control study presented here was to elucidate the incidence, risk factors, and outcomes of nosocomial infections caused by quinolone-resistant Escherichia coli (QREC). During the 3-year period studied, 51 nosocomial QREC infections were found, and the characteristics of these cases were compared with those of 102 control patients with quinolone-susceptible nosocomial infections. In the multivariate analysis, risk factors were identified as prior quinolone therapy (odds ratio [OR], 18.49; 95% confidence interval [CI], 5.53-61.82; P value <0.001), urinary tract abnormalities (OR, 6.69; 95% CI, 1.68-26.63; P=0.007), and prior therapy with other antimicrobial agents (OR, 3.57; 95% CI, 1.38-9.27; P=0.009). No difference in mortality or in length of hospital stay was found. Prudent use of quinolones, especially in patients with urinary tract abnormalities, is probably the best way to avoid an increase in the incidence of QREC infections, but further studies on interventions with restricted use of quinolones are necessary to demonstrate the effectiveness and safety of this strategy.

Adult↗

PubMed2003

Bronchiolitis caused by respiratory syncytial virus in an area of portugal: epidemiology, clinical features, and risk factors.

The aim of the present study was to analyse the clinical and epidemiological characteristics of bronchiolitis caused by respiratory syncytial virus (RSV) in 225 children observed in a paediatric hospital in Lisbon, Portugal, and to determine the clinical, epidemiological, or laboratory parameters that correlate with greater severity of the disease. This prospective study included hospitalised and ambulatory children younger than 36 months of age with a diagnosis of bronchiolitis and was conducted during two consecutive RSV epidemiological seasons (November-March 2000/01 and 2001/02). The median age of the patients was 5 months, and the male-to-female ratio was 1.6:1. RSV was isolated in 60.9% of patients, predominantly in the hospitalised group. The subtype A:B ratio was 7.4:1 and was similar in both seasons. RSV-positive patients were younger, had more severe clinical forms of bronchiolitis, and fewer changes in leucocyte total and differential counts. Among infected patients, higher clinical severity scores occurred in association with first wheezing episodes, overcrowded households, attendance at day-care centres, or prematurity (<36 weeks). This first prospective study of RSV epidemiology in Portugal provides a foundation for appropriate surveillance programmes of RSV infection in this country. A multicentre study is desirable in order to delineate optimal prophylactic and therapeutic guidelines for RSV infection in Portugal.

Age Distribution↗

PubMed2004

Risk factors for the development of extended-spectrum beta-lactamase-producing bacteria in nonhospitalized patients.

Although the risk factors for acquiring infection by extended-spectrum beta-lactamase (ESBL)-producing bacteria have been investigated in hospitalized patients, such risk factors have not been defined in the community setting. In this study, clinical data from a total of 311 nonhospitalized patients with community-acquired urinary tract infection (128 with ESBL-positive strains and 183 with ESBL-negative strains) were obtained. According to a multivariate analysis, the following were identified as independent risk factors: previous hospitalization in the past 3 months (OR=8.95, 95%CI, 3.77-21.25), antibiotic treatment in the past 3 months (OR=3.23, 95%CI, 1.76-5.91), age over 60 years (OR=2.65, 95%CI, 1.45-4.83), diabetes (OR=2.57, 95%CI, 1.20-5.51), male gender (OR=2.47, 95%CI, 1.22-5.01), Klebsiella pneumoniae infection (OR=2.31, 95%CI, 1.17-4.54), previous use of third-generation cephalosporins (P=0.014, OR=15.8, 95%CI, 1.7-143), previous use of second-generation cephalosporins (P<0.0001, OR=10.1, 95%CI, 4.2-24), previous use of quinolones (P=0.001, OR=4.1, 95%CI, 1.8-9.0), and previous use of penicillin (P=0.003, OR=4.0, 95%CI, 1.6-9.0).

Adolescent↗

PubMed2005

Prevalence and risk factors of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae in an Israeli long-term care facility.

The purpose of this study was to ascertain the prevalence of extended-spectrum beta-lactamases (ESBLs) among Escherichia coli and Klebsiella pneumoniae strains obtained from urine samples of residents of a long-term care facility and to determine the risk factors for acquisition of ESBL-producing strains. All urine samples collected from January 2003 to October 2003 that were positive for E. coli or K. pneumoniae were tested for the presence of ESBL. Records of patients with ESBL-positive (ESBL-P) samples were analyzed for clinical and demographic data. The records of a matched control group of patients whose urine samples were positive for E. coli or K. pneumoniae but were ESBL-negative (ESBL-N) were also analyzed. The overall rate of ESBLs among the E. coli and K. pneumoniae samples was 25.6%. Of 350 urine samples that grew E. coli, 77 (22%) were positive for ESBL; 34 of 84 (40.5%) samples that grew K. pneumoniae were ESBL-P. Male sex, treatment in the subacute care unit, recent antimicrobial treatment, pressure sores, (percutaneous endoscopic gastrostomy) PEG tube, anemia, hypoalbuminemia, permanent urinary catheter, and any recent invasive procedure were all associated with ESBL-P bacteria in the univariate analysis. The multivariate analysis revealed three independent risk factors for the presence of an ESBL-producing strain: anemia, permanent urinary catheter, and previous antibiotic use. Fluoroquinolones were most strongly associated with the development of ESBL-producing bacteria. The prevalence of ESBL-producing E. coli and K. pneumoniae in the long-term care facility investigated was unexpectedly high and corroborates the notion that long-term care facilities could be important reservoirs of resistant bacteria. Identification of the risk factors for ESBLs is the first step in formulating an effective strategy to curtail the spread of ESBL resistance in long-term care facilities.

Age Distribution↗

PubMed2001

Clinical and pathological review of HIV-associated lymphoma in Edinburgh, United Kingdom.

The incidence and characteristics of HIV-associated lymphoma among a cohort of patients infected predominantly through intravenous drug use are reported. Fifty-one definite cases were identified, occurring in a total cohort of approximately 1,340 individuals. The rate at which lymphoma occurred as the AIDS-defining illness did not differ significantly from that in previously published studies in which there was a preponderance of men infected through homosexual intercourse, and it was strikingly similar for all patient groups within this cohort. In patients diagnosed before death, the median survival was 103 days. Patients presenting with cerebral lymphoma had more advanced HIV infection and a shorter survival (median of 49 days compared with 149 days for extracerebral lymphoma). Although there is an apparent excess of cases (expressed as cases per 1,000 years of follow-up) among homosexual men, this is likely to be due to confounding factors, and these sources of possible bias are discussed. These data do not support the hypothesis that rates differ between different patient groups.

Adult↗

PubMed2005

Anorectal manometry: are fatigue rate and fatigue rate index of any clinical importance?

BACKGROUND: Loss of voluntary contraction of the external anal sphincter is thought to be a factor in fecal incontinence. During anal manometry, computerized systems produce several parameters including fatigue rate (FR), which is the basis for calculating the fatigue rate index (FRI). Our aim was to evaluate FR and FRI and their clinical importance in patients suffering from fecal incontinence or severe constipation. MATERIALS AND METHODS: All patients scheduled for an anal physiology work-up were included in the study. FR was determined by a computer program and FRI was calculated manually with the following equation: FRI (minutes) = [squeeze pressure (mm Hg) - resting pressure (mmHg)] / - FR (mmHg/min). FR and FRI were compared in patients suffering from fecal incontinence (group I) and severe constipation (group II). Furthermore, subgroups (<50 and > or = 50 years of age) were compared. Lastly, a possible relation between length of the high-pressure zone (HPZ) and FR and FRI was assessed. RESULTS: Between January 2000 and December 2004, 131 patients (96 with fecal incontinence, 35 with constipation) were studied. Both FR and FRI were similar between groups I and II; no significant differences were found when younger and older patients were compared within the same group. We also did not find any relation between HPZ length and either FR or FRI. CONCLUSIONS: FR and FRI do not seem to be helpful in routine colorectal practice for evaluating the strength of the external anal sphincter.

Adult↗

PubMed2005

Analysis of canine model of gastric electrical uncoupling using recurrence quantification analysis.

This study reports the results of recurrence quantification analysis (RQA) applied to internal gastric electrical activity (GEA) and cutaneous electrogastrographic (EGG) digital recordings obtained from acute canine models. The purpose of this chaos analysis is to differentiate three states--normal, mild, and severe induced electrical uncoupling--utilizing five quantities associated with RQA: percent recurrence, percent determinism, maximum deterministic line, entropy, and trend. The results indicate that percent recurrence and trend are the only quantities that relate the three states of gastric electrical uncoupling in any meaningful way. The ability of EGG to detect mild electrical uncoupling in the stomach appears to be limited due to the impact of numerous external factors on the signals, even if multichannel recordings are utilized.

Animals↗

PubMed2005

Sample size computations for PK/PD population models.

We describe an accurate, yet simple and fast sample size computation method for hypothesis testing in population PK/PD studies. We use a first order approximation to the nonlinear mixed effects model and chi-square distributed Wald statistic to compute the minimum sample size to achieve given degree of power in rejecting a null hypothesis in population PK/PD studies. The method is an extension of Rochon's sample size computation method for repeated measurement experiments. We compute sample sizes for PK and PK/PD models with different conditions, and use Monte Carlo simulation to show that the computed sample size retrieves the required power. We also show the effect of different sampling strategies, such as minimal, i.e., as many observations per individual as parameters in the model, and intensive on sample size. The proposed sample size computation method can produce estimates of minimum sample size to achieve the desired power in hypothesis testing in a greatly reduced time than currently available simulation-based methods. The method is rapid and efficient for sample size computation in population PK/PD study using nonlinear mixed effect models. The method is general and can accommodate any type of hierarchical models. Simulation results suggest that intensive sampling allows the reduction of the number of patients enrolled in a clinical study.

Algorithms↗

PubMed2006

Intracranial tumors in adult population of the Varazdin County (Croatia) 1996-2004: a population-based retrospective incidence study.

AIM: To estimate the incidence of intracranial tumors in the adult population of the Varazdin County, Croatia, for the 1996-2004 period. METHODS SETTING: Varazdin County General Hospital and four university hospitals in Zagreb, the capital of Croatia. STUDY PERIOD: January 1, 1996 to December 31, 2004. Incident patients: county residents admitted for newly diagnosed intracranial tumors according to the WHO diagnostic criteria. Demographic data were extracted from the 2001 Croatian census. Incidence rates (IRs) per 100,000 person-years (p-y) and annual IRs (per 100,000 persons) were determined and compared as incidence rate ratios (IRRs) with 95% CI. RESULTS: For primary intracranial tumors (PITs), IR was 12.1/100,000 p-y (95% CI: 10.3-14.2), comparable in men and women. The highest incidence was recorded for glioblastoma (IR 4.8, 3.7-6.2) and meningioma (IR 3.1, 2.2-4.2). The incidence of PIT was somewhat greater than that of metastatic tumors (IRR 1.58, 95% CI: 1.22-2.05, P < 0.001). Metastatic tumors were more frequent in men than in women, especially metastatic lung tumors (IRR 6.08, 2.32-20.16, P < 0.001). IRs of all PIT taken together, neuroepithelial tumors cumulatively, nonepithelial tumors cumulatively, glioblastoma and meningioma were higher in the population aged > or = 40 vs. population aged < or = 39 (all IRRs with 95% CI greater than 1, P < 0.05 or < 0.001), comparable in men and women. Women were somewhat older than men at the time of diagnosis of PIT: median difference -6 years (95.1% CI: -10 to -1, P < 0.05). Annual IRs for all these tumor categories showed increasing trends over the study period. CONCLUSION: Overall, there was an increasing trend in the incidence of primary intracranial tumors in the Varazdin County. Data did not allow estimation for most of the specific tumor types.

Adult↗

PubMed2005

The quality of life of parents of children with atopic dermatitis: interpretation of PIQoL-AD scores.

The PIQoL-AD has been used in several trials assessing quality of life (QoL) in parents of children with atopic dermatitis (AD), treated with pimecrolimus cream 1%. Secondary analysis of data from four trials (n = 621) was undertaken to help interpret the meaningfulness (significance) of the QoL results. A combination of anchor-based and distribution-based methods of interpreting instrument scores were employed. For each level on four AD severity indicators, mean PIQoL-AD scores and 95% confidence intervals were calculated. Low levels of association (r(s) range = 0.12-0.45) were observed between QoL and clinical indicators; confirming previous findings. When data from the different trials and time-points were combined clear patterns emerged indicating the clinical meaning of PIQoL-AD scores. Distribution-based statistics such as effect sizes, the standard error of measurement (SEM) and the standard error of difference (S(diff)) were also calculated. Despite a lack of consensus on how best to determine the meaningfulness of QoL scores, a large database of trial data was successfully used to link QoL scores to disease severity, aiding clinical interpretation of the former. Effect size, SEM and S(diff) values were consistent across the trials indicating that a change of 2 to 3 PIQoL-AD points over time could be considered meaningful. It is argued that it would be useful for clinicians to gain an understanding of the meaning of QoL scores through routine use of such measures in clinical practice.

Adolescent↗

PubMed2004

Comparison of erythema migrans caused by Borrelia afzelii and Borrelia garinii.

BACKGROUND: We compared epidemiological and clinical characteristics of patients with erythema migrans (EM) caused by Borrelia afzelii and Borrelia garinii. PATIENTS AND METHODS: 200 consecutive adult patients with B. afzelii isolated from the skin lesion and 53 consecutive adult patients with EM caused by B. garinii qualified for the present study. RESULTS: Comparison of the two groups revealed several distinctions. Patients with EM caused by B. garinii were older, had their skin lesions more often located on the trunk but less often on extremities, had shorter incubation and faster evolution of EM, more often reported associated local and certain systemic symptoms, had abnormal liver function test results more often and were more frequently seropositive. CONCLUSION: Early localized Lyme borreliosis caused by B. afzelii and B. garinii has distinct epidemiological and clinical characteristics. Clinical features of EM depend upon the genospecies of Borrelia burgdorferi sensu lato causing the illness.

Adolescent↗

PubMed1995

Effect of diabetes mellitus on short- and long-term mortality rates of patients with acute myocardial infarction: a statewide study. Myocardial Infarction Data Acquisition System Study Group.

We studied the effect of diabetes mellitus (DM) on mortality rate in 42,595 patients in the statewide Myocardial Infarction Data Acquisition System (MIDAS), which included patients with myocardial infarction from 90 nonfederal hospitals in New Jersey during the years 1986 and 1987. Of these patients 9695 (22.8%) had DM. DM was more prevalent among female, black, and older patients. DM was associated with higher mortality rates, both in-hospital (21.5% vs 19.2%, p < 0.001) and during 3-year follow-up (46.7% vs 37.8%, p < 0.001). This relation persisted in both men and women, blacks and whites, and all age groups. DM was an independent predictor of mortality by multivariate Cox proportional hazards regression analysis after adjustments were made for gender, race, age, hypertension, left ventricular dysfunction, chronic pulmonary disease, chronic liver disease, and anemia. This effect of DM was most pronounced in the younger age groups. Relative risk was 1.87 for age group 30 to 49, 1.36 for 50 to 69, and 1.17 for 70 to 89 years (p < 0.0001).

Adult↗

PubMed1986

Amino acid composition of the membrane and aqueous domains of integral membrane proteins.

To identify residues which might impart transport capability to the intramembranous regions of transport proteins, we surveyed available data for the 9991 amino acids contained in the aqueous and intramembranous regions of 24 integral membrane proteins: 10 transport (T) proteins and 14 nontransport (NT) proteins. Statistical comparison of percentage occurrence of each amino acid within T and NT samples provided a measure of "typical" composition of T and NT membrane-spanning regions, and showed that the residues partition into membrane and aqueous domains largely in accord with expectation from hydropathy indices. Comparison of aqueous and membrane domain composition between protein categories revealed a statistically similar distribution of residues in aqueous domains, but significant differences in membrane domains: seven residues (Asn, Asp, Gln, Glu, Phe, Pro, Tyr) were preferred in membrane regions of T proteins, and one (Val) was selectively excluded. Chemical and structural considerations suggested that three of these residues--Asn, Tyr, and Pro--are the most likely functional participants in transport processes.

Amino Acid Sequence↗

PubMed1975

The effect of chain length and lipid phase transitions on the selective permeability properties of liposomes.

This paper describes experiments showing the importance of the fatty acid chain length on the barrier properties of liposomal bilayers, prepared from saturated lecithins, under conditions of lateral phase separation. 1. Above the gel to liquid crystalline phase transition temperature, liposomes prepared from saturated lecithins with 14 or more carbon atoms per acyl chain exist as stable bilayers, which are practically impermeable to ions. 2. At temperatures well above the transition temperature dilauroyl phosphatidylcholine liposomes exhibited osmotic shrinkage, which was dependent on the ionic size of the solute used to bring about the osmotic gradient, indicating that the permeation through these less stable bilayers takes place mainly via individual diffusion of the permeating ions. 3. An enhanced release of trapped potassium from liposomes was demonstrated in the vicinity of the transition temperature. The extent of the increase, however, depended strongly on the length of the paraffin chain. 4. From measurements of the shrinkage behaviour of liposomes in the vicinity of the transition temperature it is concluded that the increased permeability decreases with increasing diameter of the permeating ion. This finding implies that the increased permeability at the transition temperature cannot be ascribed to "macroscopic" rupture of the liposomal membrane. The maximum permeability in the vicinity of the Tc is discussed in terms of probability and size distribution of statistical pore formation at the boundaries of liquid and solid domains.

Cations, Monovalent↗

PubMed1978

The interaction of liver alcohol dehydrogenase with NADH as studied by differential protein denaturation.

Heat denaturation of horse liver alcohol dehydrogenase was followed in the presence of isobutyramide at various degrees of saturation of the binding sites by NADH. A study of the fluorescence enhancement which is observed when an excess of NADH is added to the partially denatured mixtures provides information regarding the relative concentrations of mono- and bioccupied enzyme molecules. This approach is of value in situations when the association constants for coenzyme are so large that the concentration of the free ligand is negligible. The results obtained indicate that the binding of NADH to liver alcohol dehydrogenase follows the statistically predicted distribution. At the same time evidence was obtained for interaction between the two subunits of the enzyme.

Alcohol Oxidoreductases↗

PubMed1996

Autoradiographic comparison of [3H]DPDPE and [3H]DSLET binding: evidence for distinct delta 1 and delta 2 opioid receptor populations in rat brain.

The delta opioid ligands, [3H]DPDPE (delta 1) and [3H]DSLET (delta 2) were used in quantitative autoradiographic experiments to ascertain whether separate populations of delta opioid subtypes could be identified in rat brain. Densitometric image analysis showed a general similarity in delta 1 and delta 2 distributions. However, statistically significant differences in binding levels were observed in anatomically discrete regions. Examples of these regions and their delta 2/delta 1 ratio(s) are: dorsomedial hypothalamus (9.3), ventromedial hypothalamus (4.9), superior colliculis (2.7), medial division of bed nucleus stria terminalis (1.6-3.0), external cortex of the inferior colliculis (2.1), amygdaloid nuclei (1.5-2.1), cingulate cortex (1.8), CA1, CA2, and CA3 regions of Ammon's horn (1.6-2.0), dentate gyrus (1.7), laminar VI of the frontal, forelimb, hindlimb and parietal cortices (1.3-1.8), nucleus accumbens (1.4) and caudate/putamen (1.3). These findings provide evidence supporting the existence of distinct delta 1 and delta 2 opioid receptors.

Animals↗