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Autosomal dominant spinocerebellar ataxia type 1 (SCA1) is a genetic movement disorder with neuronal loss in the cerebellum, brainstem, and other cerebral regions. The course of SCA1 is accompanied with progressive weight loss and amyotrophia-the causes for that remain, however, unclear. We tested the hypothesis that an imbalance between energy intake and expenditure contributes to weight loss in SCA1 patients. Anthropometric measures, energy intake (food records), and resting (calorimetry) and free-living (accelerometry) energy expenditure were determined in 10 patients with genetically proven SCA1 and 10 healthy controls closely matched for age, sex, and body composition. At rest, energy expenditure per kilogram fat-free mass was 22 % and fat oxidation rate 28 % higher in patients vs. controls indicating an increased catabolic state. Under free-living conditions, total energy expenditure and daily step counts were significantly lower in patients vs. controls. However, most patients were able to maintain energy intake and expenditure in a balanced state. Resting energy expenditure, fat oxidation, and activity energy expenditure per step count are higher, whereas 24-h total energy expenditure is lower in SCA1 patients vs. healthy controls. An altered autonomic nervous system activity, gait ataxia, and a decreased physical activity might contribute to this outcome.

Autosomal-dominant spinocerebellar ataxia type 1 (SCA1) is an adult-onset progressive disorder with well-characterized neurodegeneration in the cerebellum and brainstem. The objective of this study is to evaluate neurochemical changes associated with neurodegeneration in cerebral tissue in SCA1 patients compared to age- and gender-matched healthy controls. Nine patients with genetically proven SCA1 and nine gender- and age-matched healthy controls were prospectively recruited from the ataxia clinic and received clinical examination. A 1.5 T single-voxel brain proton MR spectroscopy was performed for total N-acetyl aspartate (tNAA) in cerebellum, parietofrontal lobe white matter, sensory cortex, and visual cortex. In the patients, tNAA was severely decreased in the cerebellar voxel; however, in the voxels positioned in sensory cortex, parietofrontal lobe white matter and visual cortex tNAA was reduced in comparison to controls. In addition to the profoundly affected cerebellum, we also found evidence for cerebral neurodegeneration in parietal lobe white matter, sensory cortex, and visual cortex in SCA1 patients illustrating a multisystem neurodegenerative character of the disease.

Recently, we identified a novel Purkinje cell-specific autoantibody (termed anti-Ca) targeting rhoGTPase-activating-protein-26 (ARHGAP26) in a patient with cerebellar ataxia. Here we describe a new case of anti-Ca/ARHGAP26 antibody-positive cerebellar ataxia. Cerebellar ataxia was associated with signs of possible limbic encephalitis in this case. The 24-year-old man presented with subacute pancerebellar ataxia, flattened affect, and cognitive decline. Neuropsychological testing revealed working memory deficits, compromised verbal learning and recall, attention deficits, slowed information processing, interference difficulty, and reduced spatial recognition. MRI showed severe pancerebellar atrophy. Serological examinations revealed high-titre anti-Ca/anti-ARHGAP26 antibodies. The antibodies belonged to the IgG1 subclass and were produced intrathecally. This case further corroborates the association of anti-Ca antibodies with cerebellar ataxia, expands the clinical spectrum, and highlights the necessity of antigen-specific diagnostic testing in immune-mediated cerebellar ataxia., (© 2013.)

DYTCA is a syndrome that is characterized by predominant dystonia and mild cerebellar ataxia. We examined two affected siblings with healthy, consanguineous, Turkish parents. Both patients presented with a combination of childhood-onset cerebellar ataxia, dystonia, and sensory axonal neuropathy. In the brother, dystonic features were most pronounced in the legs, while his sister developed torticollis. Routine diagnostic investigations excluded known genetic causes. Biochemical analyses revealed a mitochondrial respiratory chain complex IV and a coenzyme Q10 deficiency in a muscle biopsy. By exome sequencing, we identified a homozygous missense mutation (c.154A >C; p.Thr52Pro) in both patients in exon 2 of the COX20 (FAM36A) gene, which encodes a complex IV assembly factor. This variant was confirmed by Sanger sequencing, was heterozygous in both parents, and was absent from 427 healthy controls. The exact same mutation was recently reported in a patient with ataxia and muscle hypotonia. Among 128 early-onset dystonia and/or ataxia patients, we did not detect any other patient with a COX20 mutation. cDNA sequencing and semi-quantitative analysis were performed in fibroblasts from one of our homozygous mutation carriers and six controls. In addition to the exchange of an amino acid, the mutation led to a shift in splicing. In conclusion, we extend the phenotypic spectrum of a recently identified mutation in COX20 to a recessively inherited, early-onset dystonia-ataxia syndrome that is characterized by reduced complex IV activity. Further, we confirm a pathogenic role of this mutation in cerebellar ataxia, but this mutation seems to be a rather rare cause.

Depression is common in patients suffering from end-stage renal disease (ESRD). Various screening tools for depression in ESRD patients are available. This study aimed to validate the Beck Depression Inventory-Fast Screen (BDI-FS) with the Beck Depression Inventory-II (BDI-II) as depression screening tool in conventional hemodialysis (CHD) patients. One hundred sixty two CHD patients were studied with both screening questionnaires. We used the Pearson Correlation Coefficient to measure the agreement between BDI-II and BDI-FS scores from 134 patients who responded to both questionnaires. Receiver operating characteristics curve and area under the curve were constructed to determine a valid BDI-FS cutoff score to identify ESRD patients at risk for depression. BDI-II and BDI-FS scores strongly correlated (Pearson r = 0.85, p < 0.0001). At a BDI-II cutoff ≥16, receiver operating characteristics showed the best balance between sensitivity and specificity for the BDI-FS cutoff value of ≥4 with a sensitivity of 97.2% (95% confidence interval [CI]: 85.5%, 99.9%) and a specificity of 91.8% (95% CI: 84.5%, 96.4%). When applying the above cutoff scores, prevalence of depressive symptoms in all completed questionnaires was found to be 28.7% (BDI-II) and 30.1% (BDI-FS), respectively. The BDI-FS was found to be an efficient and effective tool for depression screening in ESRD patients which can be easily implemented in routine dialysis care.

Background: Central venous catheters (CVCs) are used for vascular access in hemodialysis patients who have no alternative access or are awaiting placement or maturation of a permanent access. The major complications of CVCs are catheter-related bloodstream infection and clotting in the catheter lumen., Study Design: Parallel-group, randomized, multicenter clinical trial, with patients blinded to study intervention., Setting & Participants: 16 free-standing dialysis facilities in Northern California belonging to a single provider. 303 adult maintenance hemodialysis patients who were using a tunneled cuffed CVC for vascular access., Intervention: The treatment group received an antibiotic lock containing gentamicin 320 μg/mL in 4% sodium citrate, whereas the control group received the standard catheter lock containing heparin 1,000 U/mL. Both groups received triple-antibiotic ointment on the catheter exit site during dressing changes at each dialysis treatment., Outcomes: Catheter-related bloodstream infection and catheter clotting., Measurements: Catheter-related bloodstream infection was defined as the occurrence of symptoms consistent with bacteremia together with positive blood culture results in the absence of another obvious source of infection. Catheter clotting was measured as the rate of thrombolytic agent use required to maintain adequate blood flow. A single patient could contribute more than one infection or clotting episode., Results: The rate of catheter-related bloodstream infection was 0.91 episodes/1,000 catheter-days in the control group and 0.28 episodes/1,000 catheter-days in the treatment group (P = 0.003). The time to the first episode of bacteremia was significantly delayed (P = 0.005). The rates of tissue plasminogen activator use were similar in the treatment and control groups: 2.36 versus 3.42 events/1,000 catheter-days, respectively (P = 0.2)., Limitations: The requirement for dialysis facility staff to prepare the treatment intervention prevented a completely blinded study., Conclusion: Gentamicin 320 μg/mL in 4% sodium citrate used as a routine catheter lock in CVCs in patients on maintenance hemodialysis therapy markedly decreases the incidence of catheter-related bloodstream infection and is as effective as heparin 1,000 U/mL in preventing catheter clotting., (Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Patients on in-center nocturnal hemodialysis therapy typically experience higher interdialytic weight gain (IDWG) than patients on conventional hemodialysis therapy. We determined the safety and effects of decreasing dialysate sodium concentration on IDWG and blood pressure in patients on thrice-weekly in-center nocturnal hemodialysis therapy., Study Design: Quality improvement, pre-post intervention., Settings & Participants: 15 participants in a single facility., Quality Improvement Plan: Participants underwent three 12-week treatment phases, each with different dialysate sodium concentrations, as follows: phase A, 140 mEq/L; phase B, 136 or 134 mEq/L; and phase A(+), 140 mEq/L. Participants were blinded to the exact timing of the intervention., Outcomes: IDWG, IDWG/dry weight (IDWG%), and blood pressure., Measurements: Outcome data were obtained during the last 2 weeks of each phase and compared with mixed models. The fraction of sessions with adverse events (eg, cramping and hypotension) also was reported., Results: IDWG, IDWG%, and predialysis systolic blood pressure decreased significantly by 0.6 ± 0.6 kg, 0.6% ± 0.8%, and 8.3 ± 14.9 mm Hg, respectively, in phase B compared with phase A (P < 0.05 for all comparisons). No differences in predialysis diastolic and mean arterial or postdialysis blood pressures were found (P > 0.05 for all comparisons). The proportion of treatments with intradialytic hypotension was low and similar in each phase (P = 0.9). In phase B compared with phase A, predialysis plasma sodium concentration was unchanged (P > 0.05), whereas postdialysis plasma sodium concentration decreased by 3.7 ± 1.9 mEq/L (P < 0.05)., Limitations: Modest sample size., Conclusion: Decreasing dialysate sodium concentrations in patients undergoing thrice-weekly in-center nocturnal hemodialysis resulted in a clinical and statistically significant decrease in IDWG, IDWG%, postdialysis plasma sodium concentration, and predialysis systolic blood pressure without increasing adverse events. Prolonged exposure to higher than required dialysate sodium concentrations may drive IDWG and counteract some of the purported benefits of "go-slow" (longer session length) hemodialysis., (Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Toxin and fluid removal are the main goals of dialysis therapy for patients with end-stage renal disease. Recent data indicate that the BUN-centered delivery of dialysis therapy with high efficiency, conventional, thrice-weekly hemodialysis therapy may fall short on the likewise critically important fluid control. Extended hour, in-center nocturnal HD (INHD) emerges as one of the alternative therapies for patients whose clinical needs are not met with conventional HD or who are seeking a dialysis therapy less interfering with daytime activities. We report the logistic requirements for a nocturnal program evaluated in a pilot at a midsize non-profit dialysis provider. In-center nocturnal hemodialysis provides longer dialysis sessions similar to the thrice-weekly 8-10 hour dialysis treatments originally prescribed in the early days of dialysis. INHD allows for a more flexible lifestyle-oriented dialysis schedule and enables patients to maintain routine daytime activities. It also offers an alternative schedule for patients who require extended-hour dialysis for various medical reasons.

Background: A higher sodium gradient (dialysate sodium minus pre-dialysis plasma sodium) during hemodialysis (HD) has been associated with sodium loading; however, its role is not well studied. We hypothesized that a sodium dialysate prescription resulting in a higher sodium gradient is associated with increases in interdialytic weight gain (IDWG), blood pressure (BP) and thirst., Methods: We conducted a cross-sectional study on 1084 clinically stable patients on HD. A descriptive analysis of the sodium prescription was performed and clinical associations with sodium gradient were analyzed., Results: The dialysate sodium prescription varied widely across dialysis facilities, ranging from 136 to 149 mEq/L, with a median of 140 mEq/L. The mean pre-HD plasma sodium was 136.7 ± 2.9 mEq/L, resulting in the majority of subjects (n = 904, 83%) being dialyzed against a positive sodium gradient, while the mean sodium gradient was 4.6 ± 4.4 mEq/L. After HD, the plasma sodium increased in nearly all patients (91%), reaching a mean post-HD plasma sodium of 141.3 ± 2.5 mEq/L. We found a direct correlation between IDWG and sodium gradient (r = 0.21, P < 0.0001). After adjustment for confounders and clustering by facilities, the sodium gradient was independently associated with IDWG (70 g/mEq/L, P < 0.0001). There were no significant associations among sodium gradient and BP, whether measured as pre-HD systolic (r = -0.02), diastolic (r = -0.06) or mean arterial pressure (r = -0.04). Post-HD thirst was directly correlated with sodium gradient (r = 0.11, P = 0.02)., Conclusion: Sodium gradient is associated with statistically significant and clinically meaningful differences in IDWG in stable patients on HD.

Healthcare reform is moving toward a patient-centered model of care. Effective patient-nurse partnerships are essential in a patient-centered model of care, with the patient assuming a more active empowered role. While many play a vital role in the success of the partnership, including the patient, family, nurse, and healthcare team, this article reviews the patient, the nurse, and the partnership incorporating current evidence and case studies. The intention of this article is not to present a specific model of a successful partnership, but to provoke thought and provide available resources.

Background and Aims: Micro-morphological characteristics can influence fungal infectivity. We sought links between micro-morphology and resistance to powdery mildew in mulberry with the intention of assisting selection of disease-resistant lines., Methodology: Over 3 years and under field conditions, we evaluated 30 lines of mulberry with contrasting susceptibilities to powdery mildew (15 resistant and 15 susceptible). Disease severity was related statistically to stomatal area, stomatal density, stomatal index, upper and lower cuticular thicknesses, leaf thickness and trichome density., Principal Results: Differences between lines were significant (P <0.05) for all characters studied. Variation between the resistant and susceptible groups was statistically highly significant (P <0.01) for stomatal index, stomatal area and trichome density. The powdery mildew-resistant group was distinguished by  17.4 % lower stomatal density, 12.5 % smaller stomatal index per unit leaf area, 20.0 % greater trichome density and 18.0 % higher stomatal area compared with the susceptible group. Trichome density was negatively correlated with disease severity index and with the accumulative area under disease progression curves. Stomatal density was positively correlated with both measures of disease severity. Although stomatal area was negatively related to disease severity index (r = -0.28; P <0.05), the correlation was weak. There was no statistically significant relationship between stomatal area and the accumulative area under disease progression curves. The germplasm was partitioned into seven sub-groups based on hierarchical cluster analysis derived from pooled disease severity index scores and three highly significant micro-morphological characters. Eighty per cent of the resistant germplasm accumulated in three cluster components (A1, A2 and B2) characterized by high trichome densities and a high stomatal density and stomatal index., Conclusions: Resistance to powdery mildew in mulberry is associated with trichome and stomatal features rather than leaf and epidermal thicknesses. Trichome density, stomatal density and stomatal index are shown to be promising markers for screening powdery mildew resistance in breeding programmes.

Erythropoiesis stimulating agents (ESAs) have revolutionized the management of anemia of chronic kidney disease (CKD). Peginesatide is an investigational pegylated, peptide-based, once-monthly ESA for increasing and maintaining hemoglobin (Hb). In phase 2 studies, peginesatide increases and maintains target Hb levels in patients with CKD, both those on hemodialysis and those not on hemodialysis; phase 3 trials have recently been completed. This article discusses unmet needs in the management of anemia of CKD, presents peginesatide attributes, reviews the results of select peginesatide clinical studies, and discusses the potential value of peginesatide as an alternative anemia management option.

Usage of renal replacement modalities available for the treatment of end stage renal disease varies widely between countries, indicating that non-medical factors contribute to the choice of therapy. In the United States, 93% of the patients are treated with in-center hemodialysis (HD), about 7% undergo peritoneal dialysis (PD) and less than 1% are on home HD. In comparison, a Northern California-based nonprofit dialysis provider with home dialysis centers throughout the United States has achieved a home therapy penetration of 22%, the highest proportion of home therapies among U.S. dialysis providers. To better understand the perceptions about the various modality choices among caretakers (nephrologists and nurses) in this organization a short questionnaire was used. We examined the hypothetical setting of the caretakers being in the patient role. More than 90% of the nephrology professionals chose a home therapy as initial treatment option with close to equal distribution between PD and home HD. This pattern persisted for maintenance therapy with home HD being the preferred modality. Nephrologists' and nurses' perception of who makes modality decisions varied profoundly.

Numerous quantitative trait loci (QTLs) affecting bone traits have been identified in the mouse; however, few of the underlying genes have been discovered. To improve the process of transitioning from QTL to gene, we describe an integrative genetics approach, which combines linkage analysis, expression QTL (eQTL) mapping, causality modeling, and genetic association in outbred mice. In C57BL/6J x C3H/HeJ (BXH) F(2) mice, nine QTLs regulating femoral BMD were identified. To select candidate genes from within each QTL region, microarray gene expression profiles from individual F(2) mice were used to identify 148 genes whose expression was correlated with BMD and regulated by local eQTLs. Many of the genes that were the most highly correlated with BMD have been previously shown to modulate bone mass or skeletal development. Candidates were further prioritized by determining whether their expression was predicted to underlie variation in BMD. Using network edge orienting (NEO), a causality modeling algorithm, 18 of the 148 candidates were predicted to be causally related to differences in BMD. To fine-map QTLs, markers in outbred MF1 mice were tested for association with BMD. Three chromosome 11 SNPs were identified that were associated with BMD within the Bmd11 QTL. Finally, our approach provides strong support for Wnt9a, Rasd1, or both underlying Bmd11. Integration of multiple genetic and genomic data sets can substantially improve the efficiency of QTL fine-mapping and candidate gene identification.

Performing clinical research in the outpatient dialysis facility can be very challenging. Research protocols define time-specific and detailed procedures to be performed. In dialysis units where staff members are responsible for the delivery of life-sustaining therapy to an aging end stage renal disease patient population with multiple co-morbidities, these requirements can easily be considered too burdensome to be implemented successfully. In the authors'facility, clinical research has been successfully implemented with a close team approach supported by a dedicated research group and unit staff

Aim: Etest (AB Biodisk, Solna, Sweden) is a new rapid and accurate alternative for susceptibility testing. It also can measure the minimal inhibitory concentration. The aim of this study was to assess the prevalence of drug-resistant Mycobacterium TB (MT) in newly diagnosed tuberculous Egyptian children, and to determine the effectiveness of the Etest to detect drug-resistant MT., Methods: This prospective study included 150 newly diagnosed pulmonary and extrapulmonary tuberculous children. The organism was isolated and identified after decontamination. Antimicrobial susceptibility testing was performed by proportion method using Lowenstein-Jensen medium (PMLJ) and Etest. Minimal inhibitory concentration for both first and second line anti tuberculous drugs was determined by Etest. Comparison between the two methods was done., Results: Age range was 6 months - 15 years (mean of 7.4+/-3.3). Pulmonary tuberculosis (TB) and extrapulmonary cases were 85/150 (55.3%) and 67/150 (44.7%) respectively. Seventy three isolates of MT were obtained from patients or contacts. Using Etest, the over all drug resistant of MT was 24.7% which is resistance to one drug (any drug). Resistance to first-line drugs; isoniazid, rifampicin, streptomycin and ethambutol was 5.4%, 2.7%, 6.8% and 1.4% respectively. Rifampicin resistance strongly correlated with isoniazid resistance. The prevalence of multi-drug resistance was 2.7%. Resistance to second line was 2.7% for amikacin and 1.4% for ciprofloxacin. Etest showed an overall specificity of 97.89 and sensitivity of 81.8. Overall agreement of Etest with reference proportion method range was 94.5-100%., Conclusion: Etest appears to be a good alternative method for testing susceptibility of Mycobacterium tuberculosis.

Use of erythropoiesis-stimulating agents (ESAs) presents a significant time and cost burden in the management of anemia of chronic kidney disease (CKD). We conducted a prospective, observational, activity-based costing study to estimate the health care personnel time and resulting direct medical costs associated with administering epoetin 3 times weekly to patients with end-stage renal disease on dialysis. The study was conducted at 5 US hemodialysis centers. The personnel time and costs were derived from time and motion observations. Predicted time and cost savings were modeled for switching patients to once-monthly ESA therapy. Patients also completed a survey questionnaire to assess their level of CKD knowledge and information needs. Total per-patient-per-year (PPPY) time expended on anemia management with epoetin averaged 608 minutes (range 512-915 minutes), with an average PPPY cost of $548 (range $342-$651). Use of a once-monthly ESA, compared with epoetin, could decrease average PPPY time expenditure by 79% (127 minutes [range 96-173 minutes]) and reduce PPPY costs by 81% ($104 [range $79-$136]). The patient questionnaire reported insufficient education on CKD. Use of a once-monthly ESA to correct anemia in dialysis patients may provide substantial time, resource, and cost savings compared with current treatment practices.

Quantitative trait locus (QTL) analysis is a powerful tool for mapping genes for complex traits in mice, but its utility is limited by poor resolution. A promising mapping approach is association analysis in outbred stocks or different inbred strains. As a proof of concept for the association approach, we applied whole-genome association analysis to hepatic gene expression traits in an outbred mouse population, the MF1 stock, and replicated expression QTL (eQTL) identified in previous studies of F2 intercross mice. We found that the mapping resolution of these eQTL was significantly greater in the outbred population. Through an example, we also showed how this precise mapping can be used to resolve previously identified loci (in intercross studies), which affect many different transcript levels (known as eQTL "hotspots"), into distinct regions. Our results also highlight the importance of correcting for population structure in whole-genome association studies in the outbred stock., Competing Interests: The authors have declared that no competing interests exist.

The buttonhole method of needle insertion has been reported to be a safe and effective means of cannulation. In general, infections in patients with arteriovenous fistula access are considered to be infrequent compared to other types of accesses. Although minimal data exist regarding infection rates with buttonhole cannulation, these authors' data indicate that the infection rate with buttonhole cannulation may be underestimated.

Identifying variations in DNA that increase susceptibility to disease is one of the primary aims of genetic studies using a forward genetics approach. However, identification of disease-susceptibility genes by means of such studies provides limited functional information on how genes lead to disease. In fact, in most cases there is an absence of functional information altogether, preventing a definitive identification of the susceptibility gene or genes. Here we develop an alternative to the classic forward genetics approach for dissecting complex disease traits where, instead of identifying susceptibility genes directly affected by variations in DNA, we identify gene networks that are perturbed by susceptibility loci and that in turn lead to disease. Application of this method to liver and adipose gene expression data generated from a segregating mouse population results in the identification of a macrophage-enriched network supported as having a causal relationship with disease traits associated with metabolic syndrome. Three genes in this network, lipoprotein lipase (Lpl), lactamase beta (Lactb) and protein phosphatase 1-like (Ppm1l), are validated as previously unknown obesity genes, strengthening the association between this network and metabolic disease traits. Our analysis provides direct experimental support that complex traits such as obesity are emergent properties of molecular networks that are modulated by complex genetic loci and environmental factors.

The genus Sorangium synthesizes approximately half of the secondary metabolites isolated from myxobacteria, including the anti-cancer metabolite epothilone. We report the complete genome sequence of the model Sorangium strain S. cellulosum So ce56, which produces several natural products and has morphological and physiological properties typical of the genus. The circular genome, comprising 13,033,779 base pairs, is the largest bacterial genome sequenced to date. No global synteny with the genome of Myxococcus xanthus is apparent, revealing an unanticipated level of divergence between these myxobacteria. A large percentage of the genome is devoted to regulation, particularly post-translational phosphorylation, which probably supports the strain's complex, social lifestyle. This regulatory network includes the highest number of eukaryotic protein kinase-like kinases discovered in any organism. Seventeen secondary metabolite loci are encoded in the genome, as well as many enzymes with potential utility in industry.

Systems biology approaches that are based on the genetics of gene expression have been fruitful in identifying genetic regulatory loci related to complex traits. We use microarray and genetic marker data from an F2 mouse intercross to examine the large-scale organization of the gene co-expression network in liver, and annotate several gene modules in terms of 22 physiological traits. We identify chromosomal loci (referred to as module quantitative trait loci, mQTL) that perturb the modules and describe a novel approach that integrates network properties with genetic marker information to model gene/trait relationships. Specifically, using the mQTL and the intramodular connectivity of a body weight-related module, we describe which factors determine the relationship between gene expression profiles and weight. Our approach results in the identification of genetic targets that influence gene modules (pathways) that are related to the clinical phenotypes of interest., Competing Interests: Competing interests. The Molecular Biology Institute is a wholly-owned subsidiary of Merck & Co., Inc.

In the analysis of complex traits, congenic strains are powerful tools because they allow characterization of a single locus in the absence of genetic variation throughout the remainder of the genome. Here, we report the construction and initial characterization of a genome-wide panel of congenic strains derived from the donor strain DBA/2J on the background strain C57BL/6J. For many strains, we have carried out high-density SNP genotyping to precisely map the congenic interval and to identify any contaminating regions. Certain strains exhibit striking variation in litter size and in the ratio of females to males. We illustrate the utility of the set by "Mendelizing" the complex trait of myocardial calcification. These 65 strains cover more than 95% of the autosomal genome and should facilitate the analysis of the many genetic trait differences that have been reported between these parental strains.

We previously reported the analysis of genome-wide expression profiles and various diabetes-related traits in a segregating cross between inbred mouse strains C57BL/6J (B6) and DBA/2J (DBA). By considering transcript levels as quantitative traits, we identified several thousand expression quantitative trait loci (eQTL) with LOD score >4.3. We now experimentally address the problem of multiple comparisons by estimating the fraction of false-positive eQTL that are under cis-acting regulation. For this, we have utilized a classic cis-trans test with (B6 x DBA)F(1) mice to determine the relative levels of transcripts from the B6 and DBA alleles. The results suggest that at least 64% of cis-acting eQTL with LOD >4.3 are true positives, while the remaining 36% could not be confirmed as truly cis-acting. Moreover, we find that >96% of apparent cis-acting eQTL occur in regions that do not share SNP haplotypes. Cis-acting eQTL serve as an important new resource for the identification of positional candidates in QTL studies in mice. Also, we use the analysis of the correlation structures between genotypes, gene expression traits, and phenotypic traits to further characterize genes expressed in liver that are under cis-acting control, and highlight the advantages and disadvantages of integrating genetics and gene expression data in segregating populations.

Background: A segregating population of (C57BL/6J x DBA/2J)F2 intercross mice was studied for obesity-related traits and for global gene expression in liver. Quantitative trait locus analyses were applied to the subcutaneous fat-mass trait and all gene-expression data. These data were then used to identify gene sets that are differentially perturbed in lean and obese mice., Results: We integrated global gene-expression data with phenotypic and genetic segregation analyses to evaluate metabolic pathways associated with obesity. Using two approaches we identified 13 metabolic pathways whose genes are coordinately regulated in association with obesity. Four genomic regions on chromosomes 3, 6, 16, and 19 were found to control the coordinated expression of these pathways. Using criteria that included trait correlation, differential gene expression, and linkage to genomic regions, we identified novel genes potentially associated with the identified pathways., Conclusion: This study demonstrates that genetic and gene-expression data can be integrated to identify pathways associated with clinical traits and their underlying genetic determinants.

The goal of systems biology is to define all of the elements present in a given system and to create an interaction network between these components so that the behavior of the system, as a whole and in parts, can be explained under specified conditions. The elements constituting the network that influences the development of atherosclerosis could be genes, pathways, transcript levels, proteins, or physiologic traits. In this review, we discuss how the integration of genetics and technologies such as transcriptomics and proteomics, combined with mathematical modeling, may lead to an understanding of such networks.

This study was performed to investigate the reactivity of melatonin towards various chemical reagents to produce new derivatives of melatonin containing extra- or fused heterocyclic systems such as the imidazoindole derivatives 3, 5, 6, the triazinoindole derivatives 8a, b, the thiadiazoloindole derivative 12, the pyridinoindole derivative 16 and the aminopyrazolomelatonin derivatives 21a, b and 22a, b. The structures of the compounds were established based on the analytical and spectral data. Agonist and antagonist potency of some melatonin derivatives in clonal Xenopus laevis melanophore cells was studied in comparison with melatonin.

Background: Dialysis adequacy targets frequently are difficult to achieve in large hemodialysis patients. Dual dialyzers can be used to improve clearance. It is unknown whether series or parallel configurations are superior., Methods: Eighteen large hemodialysis patients (mean weight, 92.4 kg) were enrolled in a randomized, crossover trial to directly compare dual dialyzers in parallel and series configurations. Treatment times, blood flow rates, and dialysate flow rates were kept constant., Results: Compared with a single dialyzer, parallel dual dialyzers increased the single-pool Kt/V (spKt/V) from 1.25 +/- 0.22 to 1.43 +/- 0.29 (P < 0.003). Series dual dialyzers improved urea clearance measured by spKt/V (spKt/V(urea)) to 1.46 +/- 0.26 (P < 0.0003 compared with a single dialyzer). Kt/V and urea reduction ratio of dual dialyzers in parallel were not significantly different from those of dual dialyzers in series. Half the subjects failed to meet the National Kidney Foundation-Kidney Disease Outcomes Quality Initiative recommended adequacy target for spKt/V(urea) of 1.2 or less using a single dialyzer. With the use of dual dialyzers, 83% of subjects achieved this adequacy target. Serum levels of a middle molecule, beta2-microglobulin, were reduced 34% after 2 months of dual-dialyzer therapy. Cost analysis estimates annual net savings of 1,260 dollars with dual-dialyzer therapy, primarily from projected savings in inpatient expenses., Conclusion: In large hemodialysis patients, our study shows that dual dialyzers in parallel and series are equally effective at improving urea clearance without prolonging dialysis treatment times.

Of all the striated muscles in the bodies of mammals, only the pelvic floor muscles, which include the levator ani (LA), have resting electric activity. The cause and function of this resting myoelectric activity are not exactly known. The current study investigated the effect of intraabdominal pressure (IAP) and visceral weight on the electromyographic (EMG) activity of the LA, seeking to elucidate its cause and function. A series of 18 subjects (12 women, 6 men, mean age 38.6 years) were subjected to laparoscopic cholecystectomy for calcular cholecystitis. Prior to cholecystectomy, the resting LA EMG and IAP were recorded with the patient in the recumbent and erect positions. During laparoscopic cholecystectomy, the IAP was elevated by CO2 insufflation in increments of 5 cm of H(2)O, and the LA EMG activity was recorded for the recumbent and vertical positions during inflation and after deflation at the end of the operation. In 5/18 patients in whom laparoscopic cholecystectomy was extended to open cholecystectomy, the IAP and LA EMG were also registered. The study also included histologic examination of the LA muscle from 15 cadavers (7 adults, 8 neonates). Levator ani EMG increased ( p < 0.05) on standing. At operation, IAP elevation was associated with a significant increase of LA EMG activity. On deflation, the IAP and LA EMG activity level returned to the pre-insufflation state. In open cholecystectomy, the IAP was zero and the LA EMG recorded no activity for the recumbent position, but there was an activity for the vertical position. Histologically, the lateral part of the LA in the adult cadavers consisted solely of skeletal muscle fibers. Proceeding medially, smooth muscle fibers started to appear and gradually increase until, at the midportion, the LA split into two layers, a deep layer consisting of smooth muscle fibers and a superficial layer consisting of skeletal fibers. In neonates, the LA was composed of purely skeletal muscle fibers. The LA EMG activity seems to be related to both the IAP and the visceral weight. It is probably attributable to the presence of smooth muscle bundles in the LA muscle. The LA EMG activity increased with the elevation of the IAP and visceral weight, which resulted in increased muscle tone to oppose the augmented pressure or weight. This effect seems to be mediated through the straining-levator reflex. A chronic increase of IAP or visceral overload is suggested to affect muscle integrity and function.

In a recent study we demonstrated that the rectosigmoid junction is a large bowel segment 2.8 +/- 0.9 cm in length, which we have termed the 'sigmoidorectal canal' (SRC). In that study we showed that the SRC exerted increased intraluminal pressure, contained a thick, circular, smooth muscle layer, and reacted to sigmoid colon (SC) and rectal contraction by relaxation and contraction, respectively. These findings suggest the existence of an anatomical sphincter at the SRC. To investigate this hypothesis, in the present study we carried out a morphometric (quantitative) analysis of the musculature of the SC, SRC, and rectum. Twenty-two cadavers (13 male, 9 female; mean age = 32.3 +/- 17.6 years) were investigated. Histomorphologic studies comprised staining transverse (15 cadavers) and longitudinal (7 cadavers) sections from the SC, SRC, and rectum. Specimens were stained with H&E, Masson's trichrome, and silver stains. Morphometric studies, using image analyzer computer equipment, measured the muscle thickness of the muscularis externa (ME) of the SC, SRC, and rectum. The ME of the SRC was markedly thickened compared to the ME of the SC or rectum. In 16 specimens, the increased thickness involved mainly the circular muscle layer and in six specimens both the circular and longitudinal layers. Connective tissue septa connected the adventitia with the submucosa: these 'adventitial septa' contained nerve ganglia. 'Localized bundles' of smooth muscle fibers were detected between the circular muscle fibers. The morphometric findings showed that the mean thickness of the circular muscle layer measured 440.3 +/- 80.1 microm in the SC, 1166.1 +/- 255.4 microm in the SRC, and 394.9 +/- 123.9 microm in the rectum. This study strongly suggests the presence of an anatomic sphincter at the SRC. This sphincter may explain the higher pressure at the SRC and the response of the SRC to rectal and SC contractions. The localized smooth muscle bundles in the ME may represent a rectosigmoid pacemaker., (Copyright 2003 Wiley-Liss, Inc.)

The levator ani muscle (LAM), unlike other striated muscles has resting myoelectric activity, the cause of which is not precisely known. In a recent study this activity was suggested to be related to the presence of smooth muscle bundles in the LAM. The present study investigated this point in 25 cadaveric specimens (10 neonates, 15 adults). Histologic examination of the LAM was performed in 12 specimens, three to six slices being taken from the lateral to the medial side of each muscle, processed and stained with H&E and Masson's trichrome stain. The remaining 13 specimens were studied by direct dissection and photographed. Microscopic examination of specimens from adult cadavers showed that the lateral part of the LAM consisted of purely skeletal muscle bundles, mostly of the small-caliber type and few of the large or intermediate type. As we proceeded medially, smooth muscle bundles started to appear. Examination of slices medial to the midportion of the LAM showed that the muscle began to be separated into two layers: a deep (pelvic) one formed of smooth fibers and a superficial (perineal) one of skeletal fibers, separated by a neurovascular plane. Microscopic examination of specimens from neonates showed that the whole LAM consisted of skeletal fibers; no smooth fibers or separation into two layers were identified. By direct dissection of the adult specimens the medial part of the LAM consisted of two layers, superficial and deep, which were separated by fascia containing vessels and nerves. The muscle was thicker at its medial part and tapered laterally, with loss of demarcation, into two layers. Specimens from neonates showed no differentiation of the LAM, into two layers. It is suggested that the deep layer of the LAM, which was formed of smooth fibers, acts involuntarily, supporting the pelvic viscera by its tone and responding to variations in intra-abdominal pressure by adaptation of this tone. The superficial layer of the LAM, made of skeletal fibers, appears to represent the functional mobile part that acts voluntarily during urination or defecation. The presence of the smooth fibers in the adult LAM and not in neonates seems to be adaptational, caused by the action of intra.abdominal pressure and visceral weight. The skeletal fibers pass into various histologic stages before they transform to smooth fibers.

The reaction of either Digitoxin or Digoxin with cyanoacetic acid hydrazide gave the hydrazone derivatives 3a and 3b respectively. The reactivity of the latter products towards chemical reagents was studied to give heterocyclic derivatives with potential biological activities.

There are controversies with respect to the location, number, and function of the transverse folds of the rectum (TFR), probably because their physioanatomic aspects have not been fully investigated. The purpose of this communication was to study the anatomic and histologic structure of the TFR aiming at elucidation of their function in the light of their structure. The TFR were studied morphologically and histologically in 18 cadavers (10 male, 8 female) with a mean age of 36.6 +/- 10.4 (SD) years. Barium enema studies were also performed in 36 volunteers (20 male, 16 female; mean age 38.6 +/- 15.2 [SD] years). The number of TFR varied, the commonest findings being two and three. In a few cases, TFR were absent or exceeded three in number. Most folds extended beyond the middle of the rectal lumen; a few were narrow. They were thick at the base and tapered gradually. Microscopically, the TFR contained circular and longitudinal smooth muscle fibers; they were rarely purely mucosal. TFR varied in location dividing the rectum into compartments; an alternating side-to-side arrangement allows for a wavy movement of the stool in the rectum. The wavy movement, compartmental division, and the shelving action of the TFR are suggested to retard stool movement in the rectum so as to allow time for fecal sampling (stool or gas) and for impulses to reach the conscious level to decide whether or not to defecate. Further studies are needed to investigate the role of the TFR in clinical practice., (Copyright 2001 Wiley-Liss, Inc.)

The existence of a sphincter at the rectosigmoid junction (RSJ) is controversial. Recent studies have demonstrated a high-pressure zone within the RSJ which responds to sigmoid colon or rectal contractions by relaxation or contraction, respectively. These findings suggest the presence of a "physiological" sphincter at the RSJ. The current study investigated the anatomical and histological structure and the radiological picture of the RSJ in view of the possible existence of an anatomical sphincter at the RSJ and elucidating its function. The RSJ was studied in 28 cadavers (18 adults and 10 fully mature neonates) by dissection. A histological study of the RSJ was performed in 5 cadavers. Radiological examination using double-contrast barium enema was carried out in 50 healthy volunteers (mean age 44.2+/-14.4 years; 32 men, 18 women). The mucous membrane of the RSJ was found in folds forming a "mucosal rosette" of a mean length of 2.8+/-0.9 cm in adult specimens and 0.7+/-0.2 cm in neonates. The distal end of the mucosal rosette was sharply delineated and in some specimens protruded into the rectal lumen as a small nipple, which was surrounded by a "rectal fornix" on either side. The histological examination of the RSJ showed mucosal foldings with deep crypts surrounded by lymphocytic aggregates and marginated by muscularis mucosa. The circular muscle coat showed gradually increasing thickness towards the rectum. Nerve cells in the submucosa were located at three levels: in the vicinity of the muscularis mucosa, in the middle of the submucosa, and in the proximity of the circular muscle. Radiologically the opening of the sigmoid colon into the RSJ presented as a ring or crescent. Radiological striations representing the mucosal rosette were demonstrated. The RSJ appeared as a narrow contractile segment. The anatomical, histological, and radiological findings thus indicate that the RSJ is a segment which can be identified by its interior rather than outer aspect. The study suggests the presence of an anatomical sphincter at the RSJ which seems to regulate the passage of stools from the sigmoid colon to the rectum.

The reaction of epi-androsterone with cyanoacetyl hydrazine (2) gave the hydrazone derivative 3. The reactivity of 3 towards chemical reagents was studied to give pyridine, thiazole and thiophene derivatives.

The anatomy of the pudendal canal (PC) was studied in 26 cadavers: 10 stillborn and 16 adults (mean age, 48.2 years). Two approaches were used to expose the PC: gluteal and perineal. The PC was an obliquely lying tube with a mean length of 0.8 cm in the stillborn and 1.6 cm in the adult cadavers. It started at a mean distance of 0.8 cm from the ischial spine in the stillborn and of 1.6 cm in the adult cadavers, and ended at a mean distance of 0.7 cm and 2.6 cm, respectively, from the lower border of the symphysis pubis. The PC wall was formed by the splitting of the obturator fascia and not by the lunate fascia. The PC contained the pudendal nerve and vessels embedded in loose areolar tissue. The three branches of the neurovascular bundle arose inside the canal in all but three cadavers. The wall of the PC consisted of collagen and elastic fibers, whereas that of the obturator fascia consisted of collagen only. The PC seems to be structurally adapted to serve certain functions. The criss-cross textile arrangement of collagen fibers in its wall allows the canal to change its shape in response to changes in pudendal vessels that occur during sexual activity. The elastic recoil may not only help to "pump" the blood up the pudendal vein, but also to prevent PC subluxation. The PC may, furthermore, act as a "pulley" for the neurovascular bundle. The pulley action may be disrupted by disordered pelvic floor muscles or defecation. Knowledge of the precise anatomy of the PC is necessary to carry out PC decompression in the treatment of PC syndrome.

Purpose: The gross anatomy of the pudendal nerve branches was studied to identify more precisely the neuroanatomical relationship in the region of the anal canal, bladder neck and proximal urethra. Such knowledge is essential for the development of surgical techniques that avoid nerve injury in sphincteroplasty for anal and urinary stress incontinence, and in pudendal canal decompression., Materials and Methods: The pudendal nerve terminal branches were dissected in 7 female and 5 male formalin fixed cadavers, including 6 fully mature neonates and 6 adults, a mean age of 37.6 years. The nerves were traced from the pudendal nerve to their termination in the anal and urethral sphincters, and pelvic floor muscles., Results: The inferior rectal nerve occupied the lower half of the ischiorectal fossa. Immediately after emerging from the pudendal canal it extended a motor branch to the levator ani muscle and the cutaneous perianal and scrotal branches. The nerve terminated in the external anal sphincter at the 3 and 9 o'clock positions. Inside the pudendal canal the perineal nerve gave rise to a scrotal branch which joined the scrotal branch of the inferior rectal nerve to form the common scrotal nerve. About 2 to 3 cm. from the pudendal canal the perineal nerve extended a branch to the bulbocavernosus muscle and divided into the terminal scrotal and motor branches, which penetrated the striated urethral sphincter at the 3 and 9 o'clock positions. The deep dorsal nerve of penis or clitoris coursed forward into the ischiorectal fossa, emerged from the deep perineal pouch and penetrated the suspensory ligament to the dorsum of the penis or clitoris., Conclusions: The identification of the precise anatomical relation of the somatic nerve termination to the anal and urethral sphincters seems vital to avoid sphincter denervation during surgery for the correction of fecal and stress urinary incontinence.

Staphylococcus aureus mutants resistant to ciprofloxacin were selected both in vitro and in vivo. In-vitro selection was achieved by incubating two strains of S. aureus (MICs of ciprofloxacin of 0.5 and 4 mg/L respectively) in the presence of ciprofloxacin in concentrations equivalent to 1/2 x MIC for 24 h and isolating the mutants on agar containing the quinolone at 1, 2 or 5 x MIC. Stably-resistant mutants of both strains were isolated, although the frequency of mutation of the susceptible strain was higher than that of the resistant strain. A murine subcutaneous abscess model was used for in-vivo selection. Mice which had been infected with a ciprofloxacin-susceptible strain of S. aureus were treated for 24 h with ciprofloxacin in a dosage which yielded concentrations in the abscess cavity equivalent to 1/2 or 1 x MIC for the pathogen. Additional groups of infected mice received ciprofloxacin for varying periods in a dosage which produced concentrations at the site of infection equivalent to 1/2 x MIC. Stably-resistant mutants were isolated from the abscesses, the number of mice from which mutants were isolated and the mutational frequency being inversely proportional to the dosage of ciprofloxacin administered and the duration of treatment. The results of this study confirm that, in the treatment of patients with infections caused by S. aureus, the dosage of ciprofloxacin should be adequate to ensure inhibitory concentrations at the site of infection.

The production of virulence factors by various bacteria can be influenced by sub-inhibitory concentrations of antibiotics. The effect of six antibiotics on the production of representative extracellular enzymes and toxins produced by Staphylococcus aureus was investigated. The production of the virulence determinants coagulase, protein A, alpha and delta haemolysin was monitored in the presence of ciprofloxacin, enoxacin, chloramphenicol, gentamicin, tetracycline and methicillin. The protein synthesis inhibitors reduced the production of coagulase and protein A, and almost completely inhibited the production of the haemolysins. Haemolysin production was also reduced by ciprofloxacin and enoxacin, but these antibiotics had little effect on the production of coagulase and protein A. Methicillin stimulated the production of alpha and delta haemolysins but had no effect on the production of coagulase and protein A.

At the end of 1990 in the area of Erfurt 309 and in and around Marburg an der Lahn 348 school beginners were examined by one children's dentist under identical conditions. The results (milk teeth) showed that the caries incidence (dmfs) was comparable in both regions. However, the proportion of restored milk teeth tended to be higher in Erfurt than in Marburg. In addition, the differences in individual caries incidence were more marked. In Marburg there were more caries-free children, but children whose teeth had been damaged by caries were more seriously damaged than those in Erfurt.

One hundred and one subjects with head louse infestation were entered into two separate studies, in which a phenothrin aqueous/alcoholic lotion was compared to a carbaryl lotion and a malathion lotion. Fifty subjects were treated with a single application of the phenothrin lotion, 28 with the carbaryl lotion and 23 with the malathion lotion. In the comparative study of the phenothrin and malathion lotions an inspection on the day following treatment showed no live lice remained, but that six of the subjects treated with malathion lotion still had evidence of viable eggs (p less than 0.05). In one subject viable eggs were still evident at two weeks post-treatment. There were no cases, however, of live lice or viable eggs at four weeks post-treatment. Mild cutaneous side-effects were reported in five subjects, the incidence of which was not significantly different by treatment group. One subject in the phenothrin and carbaryl lotion comparative study had evidence of live lice at one week post-treatment with phenothrin lotion. This subject received no further treatment and was clear of both live lice and viable eggs at subsequent visits. A separate case of live lice infestation was found at two weeks post-treatment in a subject treated with phenothrin lotion and at four weeks post-treatment in two subjects treated with carbaryl lotion. As these subjects were free of live lice infestation at previous follow-up visits it was highly probable that these were cases of re-infestation from another source.(ABSTRACT TRUNCATED AT 250 WORDS)

An important issue in teaching verbal behavior to persons with severe handicaps is the transfer of stimulus control from tact (e.g., naming) to mand (e.g., requesting) relationships. Previous research has shown that topographies taught as tacts frequently fail to appear as mands unless transfer between these two response classes is explicitly programmed. Procedures promoting this transfer would provide a necessary instructional tool. Transfer from tact to mand contingencies was investigated in two adults with severe mental retardation. Correct pointing responses to line drawing symbols depicting the utensils required to access previously requested food (beverage) items were assessed prior to and following tact intervention. Mands for two of three utensils emerged following tact intervention. The results suggest transfer from tact variables to the conditioned establishing operation may be facilitated by the prior development of a minimal mand repertoire.

An important educational objective for many persons with developmental disabilities is the acquisition of verbal operants such as the mand (e.g., requesting) and tact (e.g., labeling). Mands and tacts have been described as separate response classes and several studies support this description. Consequently, an important applied issue involves implementing procedures to develop both tact and mand repertoires. The present study investigated procedures for developing mands and tacts in three learners with severe disabilities. Learners were first taught to tact, then mand food/beverage items and the utensils required to access those items by pointing to line drawings depicting the items. The results suggest that responses acquired as tacts do not readily occur as mands. "Spontaneous" manding was developed through a transfer of stimulus control procedure which brought mands under the control of conditioned establishing operations. Substantial transfer to untrained objects and transfer across response classes were frequently noted after both tact and mand interventions had occurred for some items. Variables facilitating these generalized effects are discussed.