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At least 973 records · Page 54Linked to original sources

PubMed2005

A systematic review of sociodemographic, physical, and psychological predictors of multidisciplinary rehabilitation-or, back school treatment outcome in patients with chronic low back pain.

STUDY DESIGN: A systematic review. OBJECTIVE: To determine predictors of outcome of multidisciplinary rehabilitation-or back school treatment for patients with chronic low back pain. SUMMARY OF BACKGROUND DATA: Numerous reviews have been performed to gain insight into which patients benefit from which treatment. However, no review has systematically focused on predictors from multiple domains (i.e., sociodemographic, physical, and psychological), or on treatment outcome measured as activity limitation or participation restriction. METHODS: Studies were found by searching medical and psychological databases, and screening references. Two reviewers independently assessed the methodological quality using standard criteria. Studies were only included if they met a predefined level of internal validity. A qualitative analysis was performed. RESULTS: Heterogeneity among studies in patient characteristics, predictors, treatment, and outcomes limited evidence. All reviewed studies were descriptive or exploratory in nature. Consistent evidence was found for the predictive value of pain intensity (more pain--> worse outcome), several work-related parameters (e.g., high satisfaction--> better outcome), and coping style (less active coping--> better outcome). Other sociodemographic and physical variables consistently lacked predictive value. No consistent evidence was found for other psychological variables. CONCLUSIONS: It is impossible to define a generic set of predictors of outcome of multidisciplinary rehabilitation and back schools for patients with chronic low back pain because the reviewed studies were descriptive or exploratory in nature, and most predictors were only studied once. Nevertheless, for several predictors, consistent evidence was found. Large confirmatory studies are needed to test the value of these predictors.

Chronic Disease↗

PubMed2005

Back schools for nonspecific low back pain: a systematic review within the framework of the Cochrane Collaboration Back Review Group.

STUDY DESIGN: A systematic review within the Cochrane Collaboration Back Review Group. OBJECTIVES: To assess the effectiveness of back schools for patients with nonspecific low back pain (LBP). SUMMARY OF BACKGROUND DATA: Since the introduction of the Swedish back school in 1969, back schools have frequently been used for treating patients with LBP. However, the content of back schools has changed and appears to vary widely today. METHODS: We searched the MEDLINE and EMBASE databases and the Cochrane Central Register of Controlled Trials to November 2004 for relevant trials reported in English, Dutch, French, or German. We also screened references from relevant reviews and included trials. Randomized controlled trials that reported on any type of back school for nonspecific LBP were included. Four reviewers, blinded to authors, institution, and journal, independently extracted the data and assessed the quality of the trials. We set the high-quality level, a priori, at a trial meeting six or more of 11 internal validity criteria. Because data were clinically and statistically too heterogeneous to perform a meta-analysis, we used a qualitative review (best evidence synthesis) to summarize the results. The evidence was classified into four levels (strong, moderate, limited, or no evidence), taking into account the methodologic quality of the studies. We also evaluated the clinical relevance of the studies. RESULTS: Nineteen randomized controlled trials (3,584 patients) were included in this updated review. Overall, the methodologic quality was low, with only six trials considered to be high-quality. It was not possible to perform relevant subgroup analyses for LBP with radiation versus LBP without radiation. The results indicate that there is moderate evidence suggesting that back schools have better short- and intermediate-term effects on pain and functional status than other treatments for patients with recurrent and chronic LBP. There is moderate evidence suggesting that back schools for chronic LBP in an occupational setting are more effective than other treatments and placebo or waiting list controls on pain, functional status, and return to work during short- and intermediate-term follow-up. In general, the clinical relevance of the studies was rated as insufficient. CONCLUSION: There is moderate evidence suggesting that back schools, in an occupational setting, reduce pain and improve function and return-to-work status, in the short- and intermediate-term, compared with exercises, manipulation, myofascial therapy, advice, placebo, or waiting list controls, for patients with chronic and recurrent LBP. However, future trials should improve methodologic quality and clinical relevance and evaluate the cost-effectiveness of back schools.

Humans↗

PubMed2007

Source-specific oppositional defiant disorder: comorbidity and risk factors in referred elementary schoolboys.

OBJECTIVE: To examine differences in risk factors and comorbid conditions for oppositional defiant disorder (ODD) symptom groups in a sample of 248 elementary schoolboys (ages 6-10) recruited from 1994 to 1996. METHOD: The boys and their mothers received multiple assessments of cognitive, behavioral, academic, and family functioning, including a clinic-based evaluation in Stony Brook, NY. ODD was defined using four different strategies for aggregating data from mother and teacher reports of DSM-IV symptoms. RESULTS: Source-specific ODD symptom groups had better internal validity and were more differentiated than groups defined using the other strategies. The mother-defined ODD symptom group (ODD/M) had higher levels of maternal detachment than the teacher-defined symptom group (ODD/T), and the ODD/T group had more social problems than the ODD/M group. The classification agreement group (ODD/M + T) evidenced higher levels of sensation-seeking, maternal control, and comorbid symptoms than the ODD/M and ODD/T groups. Controlling for co-occurring attention-deficit/hyperactivity disorder and conduct disorder symptoms altered some of the relationships among ODD, comorbid symptoms, and psychosocial correlates. CONCLUSIONS: Patterns of co-occurring psychiatric symptoms and psychosocial correlates of ODD symptom groups varied depending on the rater(s) used to determine group membership. Results support continued research into source specificity for conceptualizing ODD.

Attention Deficit Disorder with Hyperactivity↗

PubMed2006

Maternal exposure to caffeine and risk of congenital anomalies: a systematic review.

BACKGROUND: Caffeine is teratogenic in animal studies when administered at high concentrations. Previous review articles have concluded that maternal caffeine consumption does not influence the risk of congenital anomalies. These reviews were narrative rather than systematic. The objective of the current systematic review is to provide a critical appraisal of epidemiologic evidence. METHODS: A search of the MEDLINE/PUBMED database (1966-October 2004) was conducted for all published epidemiologic studies with maternal intake of caffeine as an exposure and major malformations as an outcome. Study characteristics were abstracted, internal validity evaluated, and study findings summarized. RESULTS: Twenty-five papers met the initial criteria for inclusion, of which 18 were subsequently excluded as a result of other limitations. Effect estimates for the remaining 7 studies were generally close to null. Specific subgroup analyses were summarized across studies (associations between coffee and cardiovascular malformations, coffee and oral clefts, and tea and cardiovascular malformations). Summary point estimates ranged from 1.0 to 1.2; the upper limits of all confidence intervals were less than 1.7. CONCLUSIONS: There is no evidence to support a teratogenic effect of caffeine in humans. Current epidemiologic evidence is not adequate to assess the possibility of a small change in risk of congenital anomalies resulting from maternal caffeine consumption.

Adolescent↗

PubMed2004

Resrad-recycle: a computer model for analyzing radiation exposures resulting from recycling radioactively contaminated scrap metals or reusing radioactively surface-contaminated materials and equipment.

RESRAD-RECYCLE is a computer code designed by Argonne National Laboratory (ANL) to be used in making decisions about the disposition of radioactively contaminated materials and scrap metals. It implements a pathway analysis methodology to evaluate potential radiation exposures resulting from the recycling of contaminated scrap metals and the reuse of surface-contaminated materials and equipment. For modeling purposes, it divides the entire metal recycling process into six steps: (1) scrap delivery, (2) scrap melting, (3) ingot delivery, (4) product fabrication, (5) product distribution, and (6) use of finished product. RESRAD-RECYCLE considers the reuse of surface-contaminated materials in their original forms. It contains representative exposure scenarios for each recycling step and the reuse process; users can also specify scenarios if desired. The model calculates individual and collective population doses for workers involved in the recycling process and for the public using the finished products. The results are then used to derive clearance levels for the contaminated materials on the basis of input dose restrictions. The model accounts for radiological decay and ingrowth, dilution and partitioning during melting, and distribution of refined metal in the various finished products, as well as the varying densities and geometries of the radiation sources during the recycling process. A complete material balance in terms of mass and radioactivity during the recycling process can also be implemented. In an international validation study, the radiation doses calculated by RESRAD-RECYCLE were shown to agree fairly well with actual measurement data.

Body Burden↗

PubMed2004

Differentiating acute bacterial meningitis from acute viral meningitis among children with cerebrospinal fluid pleocytosis: a multivariable regression model.

BACKGROUND: Although accurate models for predicting acute bacterial meningitis exist, most have narrow application because of the specific variables selected for them. In this study, we estimate the accuracy of a simple new model with potentially broader applicability. METHODS: On the basis of previous reports, we created a reduced multivariable logistic regression model for predicting bacterial meningitis that relies on age (years) (AGE), cerebrospinal fluid (CSF), total protein (TP) and total neutrophil count (TNC) alone. Data were from children ages 1 month-18 years diagnosed with acute enteroviral or bacterial meningitis whose initial CSF revealed >7 white blood cells/mm. A fractional polynomial model was specified and validated internally by the bootstrap procedure. The area under the receiver operating characteristic curve (discrimination: criterion standard, >0.7), the Hosmer-Lemeshow deciles-of-risk statistic (calibration: criterion standard, P > 0.05) and sensitivity-specificity pairs at prespecified probability thresholds of the model were computed. RESULTS: We identified 60 children with bacterial meningitis and 82 with enteroviral meningitis. At an area under the receiver operating characteristic curve of 0.97, our model represented by the equation: log odds of bacterial meningitis = 0.343 - 0.003 TNC - 34.802 TP + 21.991 TP - 0.345 AGE, was highly accurate when differentiating between bacterial and enteroviral meningitis. The model fit the data well (Hosmer-Lemeshow statistic; P =[r] 0.53). At probability cutoffs between 0.1 and 0.4, the model had sensitivity values between 98 and 92% and specificity values between 62 and 94%. CONCLUSIONS: Among children with CSF pleocytosis, a prediction model based exclusively on age, CSF total protein and CSF neutrophils differentiates accurately between acute bacterial and viral meningitis.

Acute Disease↗

PubMed2003

A nomogram to predict seminal vesicle invasion by the extent and location of cancer in systematic biopsy results.

PURPOSE: We determined whether systematic biopsy results increases the accuracy of standard clinical information in predicting seminal vesicle invasion (SVI). MATERIALS AND METHODS: We analyzed a retrospective cohort of 763 patients with clinical stages T1c-T3 prostate cancer who were diagnosed by systematic biopsy and treated with radical prostatectomy. We recorded the location of each biopsy core and measured the length of cancer and total length of each core. Using logistic regression analysis we constructed and internally validated a nomogram to predict SVI. RESULTS: A total of 60 patients (7.9%) had SVI. Cancer was present in a biopsy core from the base in 437 patients, of whom 12.8% had SVI compared with only 1.2% of the 326 without cancer at the base. None of the 275 patients with prostate specific antigen (PSA) 10 ng/ml or less and no cancer at the base had SVI. On multivariate analysis serum PSA (p <0.0005), primary Gleason grade (p = 0.028) and percent cancer at the base (p <0.005) were the only significant predictors of SVI. The predictive accuracy of a standard model that included only stage, grade and PSA was maximally enhanced by including the percent cancer at the base (p = 0.0013). A nomogram that incorporated this variable produced probabilities of SVI that differed from the standard model by +/- 10% in 68% of the cases. CONCLUSIONS: The presence and amount of cancer in systematic needle biopsy cores from the base of the prostate strongly predicts the presence of SVI. Systematic biopsy results enhance the accuracy of nomograms to predict SVI.

Adult↗

PubMed2004

Sexual function in ankylosing spondylitis: a study of 65 men.

PURPOSE: We evaluated sexual function in male patients with ankylosing spondylitis (AS) using the validated International Index of Erectile Function (IIEF). We also assessed the frequency and association of erectile dysfunction with patient age, disease duration, morning stiffness, laboratory activity, disease severity, depression status and medication use in this patient group. MATERIALS AND METHODS: We evaluated sexual function, in particular erectile dysfunction (ED), using the IIEF in male patients with AS followed regularly at the outpatient clinic of rheumatology and compared results with those in healthy controls. Patient age, disease duration, morning stiffness, laboratory activity, disease severity and medication use were obtained by reviewing the medical record. Affective patient and control states were measured by the Beck Depression Inventory. The Bath AS Functional Index was used to measure functional status in AS cases. RESULTS: To our knowledge this is the first study of the frequency of ED in men with AS (8 of 65 or 12%). Compared to healthy controls patients with AS had significantly lower erectile function, orgasmic function, intercourse satisfaction and overall satisfaction scores according to the IIEF, whereas sexual desire scores were also lower, although not significantly. According to self-reported patient data ED was a prominent characteristic of our population. We were not able to relate any clinical features or laboratory findings to ED except the duration of morning stiffness. The 22 men with a high degree of morning stiffness (greater than 4 hours) had lower erectile function scores compared to the 12 with AS and a low degree of morning stiffness (less than 2 hours) (18.3 +/- 1.6 vs 26.5 +/- 2.4, p <0.05). Of 65 patients with AS 25 (38%) were depressed in our study group according to the Beck Depression Inventory, while no healthy controls were depressed when a score of greater than 13 was used as the cutoff. CONCLUSIONS: ED can be seen in the course of AS. The pathogenesis of ED in patients with AS is thought to be multifactorial with disease and treatment related factors. Thus, male patients with AS, in particular those with a high degree of morning stiffness, should be encouraged to talk about their sexuality.

Adult↗

PubMed2004

Health related quality of life assessments for patients with bladder cancer.

PURPOSE: We review the current data regarding the impact of various therapeutic alternatives for bladder cancer on health related (HR) quality of life (QOL). MATERIALS AND METHODS: A MEDLINE search of the English literature from 1966 to November 2003 using the search terms "cystectomy," "intravesical therapy" or "bladder cancer" and quality of life yielded 33 articles. Studies of metastatic disease were excluded. The method of evaluation of quality of life in each article was assessed, particularly the instruments used and the population studied. RESULTS: The majority of these reports (20 of 33) compared the impact of different types of urinary diversion on quality of life. The reports provided conflicting data, with several studies showing no significant difference in overall QOL. Some studies revealed a greater improvement in HRQOL with time following continent diversion. Only 2 reports discussed evaluation of HRQOL during intravesical therapy. Either an established standardized QOL instrument or an internally validated instrument was used in all but 8 of the studies. No reports compared the HRQOL effects of bladder sparing treatments to radical cystectomy. CONCLUSIONS: There is no single measure of HRQOL predominantly used in patients with bladder cancer. There is a lack of data comparing HRQOL outcomes in patients receiving bladder sparing therapies versus cystectomy. Development of a universally applicable validated instrument would allow a more effective comparison of HRQOL outcomes in these patients as well as in those with superficial and muscle invasive bladder cancer.

Humans↗

PubMed2005

Is orthotopic bladder replacement the new gold standard? Evidence from a systematic review.

PURPOSE: In this systematic review we determined whether the outcome of orthotopic bladder replacement is superior to that of continent and incontinent urinary diversion. MATERIALS AND METHODS: We searched MEDLINE, PubMed, EMBASE, CINAHL and the Cochrane Library from January 1990 to January 2003. A total of 3,370 abstracts were reviewed, including all types of studies from prospective, randomized, controlled studies to small, retrospective series. All relevant articles with at least 10 patients and a mean followup of at least 1 year were retrieved. There were no language restrictions. NonEnglish articles were translated. Comparisons were made between the major surgery types, including ileal conduit, continent diversion, bladder reconstruction and bladder replacement. All studies were scored using a predetermined quality assessment checklist to assess internal validity (bias and confounding) and external validity. RESULTS: A total of 405 studies met inclusion criteria. There were 32 prospective and 373 retrospective studies describing a total of 32,795 patients. The majority of studies were incompletely or poorly described and outcomes were often not defined. When they were defined, definitions varied. In clinical outcomes ileal conduit diversions had the lowest operative complications rate but highest reported postoperative morbidity. They also had a higher reported incidence of symptomatic urinary tract infections. The rates of postoperative morbidity, mortality and need for reoperation varied widely among studies even for the same procedure. Of physiological outcomes metabolic acidosis was the most commonly reported metabolic complication in patients with various urinary diversions. The quality of the reported literature was poor. There were no studies of the health economic implications of performing 1 type of surgery vs another type. CONCLUSIONS: While enthusiasts regard orthotopic bladder replacement as the new gold standard when lower urinary tract function must be replaced, the level and quality of current evidence are poor. The immediate concern must be to rectify this paucity of evidence with well designed and well reported prospective studies, ideally in a randomized setting, comparing the various major forms of urinary diversion and bladder replacement surgery.

Humans↗

PubMedDate not supplied

Application of two-point assay of digoxin serum concentration in studying population pharmacokinetics in Egyptian pediatric patients with heart failure: does it make sense?

Digoxin pharmacokinetics (PK) was studied among a selected group of Egyptian pediatric patients (n = 40) with an age range of 0.33 to 15 years. All the patients had heart failure and were maintained on i.v. digoxin (10 microg/kg/d in 2 equal doses). For population PK analysis, 2 serum samples of digoxin were taken per patient. From 30 patients' trough (before the next dose) and 4 hours postdose samples were obtained, while in the other 10 patients, 0.5- and 6-hour postdose samples were taken. Serum concentrations were measured by fluorescence polarization immunoassay. PK modeling was performed using NONMEM software on log-transformed serum digoxin data. The best structural covariate-free model was a linear 2-compartment model with an exponential error model for intersubject variability and an additive model for intrasubject variability. Serum creatinine (SCR) was a significant covariate for clearance. The final population PK parameters were CL (L/h) = 0.388 - [0.78 x (SCR-0.6)], V1 (L/kg) = 1.38, Q (L/h/kg) = 0.48, V2 (L/kg) = 9.11, where CL is the total body clearance, V1 and V2 are the apparent volumes of distribution in the central and peripheral compartments, and Q is intercompartment clearance. A bootstrap resampling for internal validation achieved excellent agreement with the original data sets for PK parameters. In conclusion, 2 points of digoxin concentration allow good regression analysis for clearance-covariate relationship. The inclusion of SCR into the final model might allow better selection of initial maintenance dose of the drug. A prospective study on larger sample size of pediatric patients is recommended for clinical validation of the final model.

Adolescent↗

PubMed2004

Children with cancer, fever, and treatment-induced neutropenia: risk factors associated with illness requiring the administration of critical care therapies.

OBJECTIVES: To identify clinical and laboratory characteristics of pediatric patients with cancer, fever, and treatment-induced neutropenia, available at existing at initial presentation, that are independently associated with the development of illnesses requiring administration of critical care therapies. METHODS: We retrospectively collected historical, clinical, and laboratory data on initial presentation for all pediatric (younger than 18 years) cancer patients admitted for fever and treatment-induced neutropenia at our institution over a 5-year period. The outcome variable was the need for administration of a critical care therapy within 24 hours of admission. A multivariable analysis was performed and internally validated using bootstrap analysis. RESULTS: We identified 303 events in 143 patients, of which 36 (11.9%) received a critical care therapy. Higher temperature at presentation and capillary filling time (CFT) of >3 seconds retained significance in the multivariable analysis and were validated by the bootstrap analysis. The positive and negative predictive values of the presence of either temperature of > or =39.5 degrees C or CFT of >3 seconds were 35% and 91%, respectively. CONCLUSIONS: Pediatric patients with cancer, fever, and treatment-induced neutropenia who present with higher fever or prolonged CFT are at increased risk of developing life-threatening illnesses requiring administration of critical care therapies, independent of hematologic factors, type of cancer, or other physiologic signs of sepsis.

Adolescent↗

PubMed2005

Adjuvant radiotherapy is associated with increased sexual dysfunction in male patients undergoing resection for rectal cancer: a predictive model.

OBJECTIVES: The objectives of this study were to evaluate the effect of radiotherapy (RT) on sexual function in patients undergoing oncologic resection for rectal cancer, and to develop a mathematical model for quantifying the risk of sexual dysfunction through time for this group of patients. METHODS: Data were prospectively collected on patients undergoing proctosigmoidectomy (group 1: n = 101) or adjuvant radiotherapy (40-50 Gy) and resection (group 2: n = 100) for rectal cancer at a tertiary referral center between December 1998 and July 2004. Study end points were recorded at 7 time intervals (preoperatively, 4 months, 8 months, 1 year, 2 years, 3 years, and 4 years after surgery) and included: 1) ability to have an erection, 2) maintain an erection, 3) attain orgasm, 4) dry orgasm, and 5) whether they were sexually active. Multilevel logistic regression analysis for repeated measures was used to identify factors associated with the sexual dysfunction. A predictive model was developed and internally validated by comparing observed and model-predicted outcomes. RESULTS: Radiotherapy had an adverse effect on the ability to get an erection, maintain an erection, attain orgasm, and being sexually active in comparison with patients undergoing surgery alone (7.4%, 12.6%, 16.2%, and 13.7% reduction 8 months after surgery respectively; P < 0.05). The effect of sexual dysfunction deteriorated with age (odds ratio for erectile function, 0.40 per 10-year increase in age; 95% confidence interval, 0.29-0.49; P < 0.001). A significant variability in sexual function was present among the 7 time points with a maximal deterioration occurring at 8 months after surgery with subsequent slow but not complete recovery (P < 0.001). The predictive model showed adequate discrimination on 4 of the 5 domains of sexual dysfunction (area under the receiver operating characteristic curve >0.70). CONCLUSIONS: Radiotherapy has an adverse effect on sexual function, the effect being maximal at 8 months after surgery. The risk of sexual dysfunction can be quantified preoperatively using the proposed index and can assist patients in making better informed choices on the type of treatment they receive.

Aged↗

PubMed2006

Subtype specific prognostic nomogram for patients with primary liposarcoma of the retroperitoneum, extremity, or trunk.

OBJECTIVE: To determine the prognostic significance of histologic subtype in a large series of patients with primary liposarcoma (LS) and to construct a LS-specific postoperative nomogram for disease-specific survival (DSS). SUMMARY BACKGROUND DATA: Nomograms, used to define and predict outcome following operative intervention, may contain variables not conventionally used in standard staging systems. A 12-year DSS postoperative nomogram for all sarcomas has already been established. METHODS: From a single-institution prospective sarcoma database, patients with primary extremity, truncal, or retroperitoneal LS treated between 1982 and 2005 were identified. Histology was reviewed by a sarcoma pathologist and divided into 5 subtypes. A nomogram predictive of 5- and 12-year DSS was developed. RESULTS: Of 801 patients with primary LS resected with curative intent, 369 (46%) presented with well-differentiated, 143 (18%) dedifferentiated, 144 (18%) myxoid, 81 (10%) round cell, and 64 (8%) pleomorphic histology. The median tumor burden was 15 cm (range, 1-139 cm). At last follow-up, 560 patients were alive with a median follow-up time of 45 months (range, 1-264 months) and 51 months for surviving patients. The 5- and 12-year DSS rates were 83% (95% confidence interval [CI], 80%-86%) and 72% (95% CI, 67%-77%), respectively. The nomogram was drawn on the basis of a Cox regression model. The independent predictors of DSS were age, presentation status, histologic variant, primary site, tumor burden, and gross margin status. The nomogram was internally validated using bootstrapping and shown to have excellent calibration. The concordance index was 0.827 compared with 0.776 for the general sarcoma postoperative nomogram for 12-year DSS. CONCLUSION: The LS-specific nomogram based on histologic subtype provides more accurate survival predictions for patients with primary LS than the previously established generic sarcoma nomogram. DSS nomograms aid in more accurate counseling of patients, identification of patients appropriate for adjuvant therapy, and stratification of patients for clinical trials and molecular analysis.

Adolescent↗

PubMed2005

Clinical trial design in schizophrenia: implications for clinical decisions.

PURPOSE OF REVIEW: Results from clinical trials do not necessarily provide information for decisions in clinical practice. This review aims to present strengths and limitations of different methodological types of clinical trials and to offer an overview of how knowledge from clinical trails can be distilled for clinical practice. Selected key questions in the treatment of schizophrenia are presented, with a focus on the possibilities and restrictions of translating trial results into real-world practice. RECENT FINDINGS: Randomized controlled trials are the gold standard for proving efficacy of a diagnostic or therapeutic procedure. They have a high degree of internal validity and a clear-cut message when conducted to good-quality standards but suffer from a lack of generalizability (external validity). Effectiveness studies evaluate effects of treatments under conditions approximating usual care. They may include patient-centred outcomes or health economic evaluations. According to the type of trial, specific problems arise in the interpretation of results. Typical examples are given for the treatment of acute exacerbations of schizophrenia, for relapse prevention and for the treatment of cognitive impairment. SUMMARY: Clinical decisions have to be made upon the best knowledge. Therefore, well conducted studies addressing all major issues from all relevant perspectives are needed. The assessment of a treatment regimen for clinical utility requires both efficacy and effectiveness studies. An understanding of the design, analysis and conventions of both study types is essential for the interpretation of results and their translation to the clinical decision-making process.

Journal Article↗

PubMed2002

Identification of coryneform bacteria and related taxa by Fourier-transform infrared (FT-IR) spectroscopy.

An extensive Fourier-transform infrared (FT-IR) spectroscopy database for the identification of bacteria from the two suborders Micrococcineae and Corynebacterineae (Actinomycetales, Actinobacteria) as well as other morphologically similar genera was established. The database consists of averaged IR spectra from 730 reference strains, covering 220 different species out of 46 genera. A total of 192 species are represented by type strains. The identity of 352 reference strains was determined by comparative 16S rDNA sequence analysis and, if necessary, strains were reclassified accordingly. FT-IR frequency ranges, weights and reproducibility levels were optimized for this section of high-G+C gram-positive bacteria. In an internal validation, 98.1% of 208 strains were correctly identified at the species level. A simulated external validation which was carried out using 544 strains from 54 species out of 16 genera resulted in a correct identification of 87.3% at the species level and 95.4% at the genus level. The performance of this identification system is well within the range of those having been reported in the literature for the identification of coryneform bacteria by phenotypical methods. Coryneform and related taxa display a certain degree of overlapping distribution of different taxonomical markers, leading to a limited differentiation capacity of non-genotypical identification methods in general. However, easy handling, rapid identification within 25 h starting from a single colony, a satisfactory differentiation capacity and low cost, render FT-IR technology clearly superior over other routine methods for the identification of coryneform bacteria and related taxa.

Actinomycetales↗

PubMed2001

The short-EMBU in East-Germany and Sweden: a cross-national factorial validity extension.

The factorial stability and reliability of the 23-item s(hort)-EMBU previously demonstrated to be satisfactory in samples of students from Greece, Guatemala, Hungary and Italy, were extended with 791 students from East-Germany and Sweden. Previous findings on factorial validity, internal reliability and correlations among scales were replicated. The 23-item form thus continues to be recommended as a reliable functional equivalent to the early 81-item EMBU, when the clinical and/or research context does not adequately permit application of time-consuming test batteries.

Adolescent↗

PubMed2025

Integrative metabolomic and proteomic analysis of diabetic kidney disease progression with younger-onset type 2 diabetes.

AIM: Younger-onset type 2 diabetes (YT2D) confers a disproportionately high risk of diabetic kidney disease (DKD), yet early biomarkers and underlying mechanisms remain poorly defined. We aimed to identify metabolites associated with DKD progression and integrate metabolomic and proteomic data to elucidate pathways involved in a multi-ethnic Asian cohort. MATERIALS AND METHODS: In this prospective study, 787 YT2D patients (diagnosed at ≤ age 40) were followed for a median of 5.7 years. DKD progression was defined as an annual decline in estimated glomerular filtration rate (eGFR) of ≥3 mL/min/1.73 m2 or ≥ 40% reduction in eGFR from baseline. Plasma metabolites were measured by nuclear magnetic resonance spectroscopy. Multivariable regression analysis was performed in a discovery (N = 550) and internal validation cohort (N = 237). Integrative metabolomic-proteomic analysis (N = 428) was performed using sparse partial least squares discriminant analysis (sPLS-DA). RESULTS: Ninety-eight metabolites were differentially expressed between DKD progressors and non-progressors, of which total branched-chain amino acids (BCAAs) (OR = 0.60, 95% CI 0.46-0.79), valine (OR = 0.62, 95% CI 0.48-0.81), and leucine (OR = 0.56, 95% CI 0.43-0.74) associated with DKD progression, independent of metabolic risk factors. Integrative analysis identified three components comprising 23 proteins and 30 metabolites, involved in the citrate cycle and apoptosis, which improved prediction of DKD progression beyond clinical risk factors (AUC 0.69-0.83). CONCLUSION: Lower plasma BCAA levels are independently associated with DKD progression in YT2D. Integrative multi-omics analysis highlights disruptions in metabolic and apoptotic pathways, providing insights into DKD pathophysiology and potential biomarkers for early risk stratification.

Humans↗