Study of electron-beam propagation through preionized dense foam plasmas

The transport of an intense electron-beam produced by the Vulcan petawatt laser through dense plasmas has been studied by imaging with high resolution the optical emission due to electron transit through the rear side of coated foam targets. It is observed that the MeV-electron beam undergoes strong filamentation and the filaments organize themselves in a ringlike structure. This behavior has been modeled using particle-in-cell simulations of the laser-plasma interaction as well as of the transport of the electron beam through the preionized plasma. In the simulations the filamentary structures are reproduced and attributed to the Weibel instability.

Age effects on interleukin-6 and interleukin-1beta responses to endurance exercise in patients with neuromuscular diseases

Plasma IL-6 before and 20 min after prolonged muscular exercise for 20 min at the individual aerobic/anaerobic threshold was analyzed in patients with neuromuscular diseases and in controls. Patients were assigned to the following diagnostic categories: Controls (n=18); amyotrophic lateral sclerosis (n=7); peripheral neuropathy (n=6); muscular dystrophy (n=13); mitochondriopathy (n=3); myopathy (others) (n=3); inflammatory myopathy (n=6); mononeuropathy (n=4). The concentrations of IL-6 before exercise were 5.55+/-0.94 pg/ml, and 6.52+/-0.97 pg/ml after exercise (P=0.0001). We introduced the independent variables age, sex and diagnostic category into a stepwise multiple linear regression model. Age emerged as a significant predictor of the IL-6 ratio (IL-6 post exercise/lL-6 before exercise). The regression equation was: IL-6 ratio=0.87+0.009xage (years), R=0.33, P<0.01, simple linear regression model. All IL-1beta concentrations were below the sensitivity of the assay (5 pg/ml). Concerning patients with neuromuscular diseases, the age associated increased IL-6 release after exercise could mean additional muscle damage.

[The prevalence of pain and deformities in the feet of adolescents. Results of a cross-sectional study]

AIM

The purpose of the study was to evaluate the prevalence of foot pain and foot deformities in adolescents. It was aimed to obtain information on the association between foot pain and foot deformities.

METHOD

A total of 2 368 adolescents (age 14.5 +/- 0.7 years) were evaluated. The frequency of foot pain was probed by using a self-reporting questionnaire. The foot deformities were evaluated during clinical examinations by school doctors.

RESULTS

The prevalence of foot pain was 14.0 % and the prevalence of foot deformities was 13.7 %. The prevalence of pain was significantly higher in adolescents with foot deformity (17.8 %) than in persons without deformity (13.4 %), p < 0.05. The prevalence of a flexible flat foot was 6.2 % and the prevalence of a rigid flat foot was 0.5 %. Other deformities registered were splay foot (2.3 %) and flexible splay-flat foot (2.0). The prevalence of hallux-valgus deformity was 3.5 %. A total of 3.5 % patients were suffering from a plantar hyperkeratosis. This was significantly correlated to a high pain prevalence (the hyperkeratosis was significantly associated with a high prevalence of pain). Significant factors which were significantly associated with foot pain were foot deformity (1.4 fold) and hyperkeratosis (75 fold). Foot pain was 1.4 fold higher in children with foot deformity and 75 fold higher in feet with hyperkeratosis.

CONCLUSION

The prevalence of foot pain and foot deformity in adolescent is high. Mild deformities (flexible flat foot and splay foot) are physiological variations without any association to foot pain. Pathological conditions that are associated with foot pain are the rigid flat foot, the hallux valgus and the cavus deformity. Plantar hyperkeratosis is an indicator of foot pathology.

Pharmacokinetics of perfluorooctanoate in cynomolgus monkeys

The pharmacokinetics of perfluorooctanoate (PFOA) in cynomolgus monkeys were studied in a six-month oral capsule dosing study of ammonium perfluorooctanoate (APFO) and in a single-dose iv study. In the oral study, samples of serum, urine, and feces were collected every two weeks from monkeys given daily doses of either 0, 3, 10, or 20 mg APFO/kg. Steady-state was reached within four weeks in serum, urine, and feces. Serum PFOA followed first-order elimination kinetics after the last dose, with a half-life of approximately 20 days. Urine was the primary elimination route. Mean serum PFOA concentrations at steady state in the 3, 10, and 20 mg/kg-day dose groups, respectively, were 81, 99, and 156 microg/ml in serum; 53, 166, and 181 microg/ml in urine; and, 7, 28, and 50 microg/g in feces. Mean liver concentrations reached 16, 14, and 50 microg/g in the 3, 10, and 20 mg/kg groups, respectively. In the iv study, three monkeys per sex were given a single dose of 10 mg/kg potassium PFOA. Samples were collected through 123 days. The terminal half-life of PFOA in serum was 13.6, 13.7, and 35.3 days in the three male monkeys and 26.8, 29.3, and 41.7 days in the three females. Volume of distribution at steady state was 181 +/- 12 and 198 +/- 69 ml/kg for males and females, respectively. Based on the result of both the oral and iv studies, the elimination half-life is approximately 14-42 days, and urine is the primary route of excretion.

Prävalenz funktioneller Beschwerden des Rückens und der Hüft- und Kniegelenke bei Adoleszenten

OBJECTIVE

To determine the prevalence of functional back, hip and knee pain in adolescents. Risk factors which are associated with these complaints also should be detected.

METHODS

A total of 2368 adolescents were included (1137 male, 1231 female, age 14.5 +/- 0.7 years). The persons were interviewed in a self-reported questionnaire about episodes of back, hip and knee pain, furthermore sociodemographic information, activity in sports and consumption of legal drugs (tobacco and alcoholic beverages). All adolescents were examined by school doctors to determine back, hip and knee pathologies.

RESULTS

A total of 62.4 % of the adolescents were suffering from musculo-skeletal pain (back 45.4 %, hip 6.4 % and knee 33.6 %). The prevalence of pathological findings was: back 18.0 %, hip 2.7 % and knee 28.5 %. Summarized the prevalence of functional pain was 34.5 % for back pain, 5.7 % for hip pain and 28.5 % for knee pain. There were significantly with functional pain associated factors. Male sex was significantly associated with functional back and hip pain. Knee pain was associated with sports activity. Adolescents who were visiting a high school and adolescents who were smoker had a significant higher prevalence of functional pain.

CONCLUSION

The majority of functional back, hip and knee pain in adolescents must be classified as functional complaints. There is a significant association with female sex, visiting a high school and the consumption of legal drugs.

Surveillance of multi-drug resistant Pseudomonas aeruginosa in an urban tertiary-care teaching hospital

Antimicrobial resistance in Pseudomonas aeruginosa is a serious clinical problem. To determine the incidence of multi-drug resistant P. aeruginosa, resistance rates of P. aeruginosa clinical isolates against commonly used antibiotics were evaluated for the period 1998 to 2002. Multi-drug resistance was defined as resistance to at least three of the four drugs, ceftazidime, imipenem, ciprofloxacin, and tobramycin. Resistance to most anti-pseudomonal agents has increased by >20% over the five-year period, with dramatic increases observed with fluoroquinolones, tobramycin, and imipenem (resistance increased by 34-37%). In 1998, 78% of isolates were susceptible to all four anti-pseudomonal agents and no isolate was considered multi-drug resistant. However, in 2002, only 27% of isolates were sensitive to all four of the drugs and 32% were considered multi-drug resistant. Multi-drug resistance in individual institutions may be significantly higher than rates reported in nationwide surveillance studies and may more accurately reflect the true magnitude of local resistance problems. On-going surveillance within individual institutions is critical for the selection of appropriate empiric antimicrobial therapy.

Use of exogenous erythropoietin in critically ill patients

OBJECTIVE

Review the literature regarding the use of recombinant human erythropoietin (rHuEPO) to prevent red blood cell (RBC) transfusion in critically ill patients.

DATA SOURCES

A computerized search of MEDLINE and EMBASE from 1966 through June 2003 was conducted using the terms erythropoietin, anemia, hemoglobin, critical care, intensive care, surgery, trauma, burn, and transfusion. References of selected articles were reviewed. A manual search of critical care, surgery, trauma, burn, hematology, and pharmacy journals was conducted to identify relevant abstracts.

RESULTS

Six randomized studies have evaluated exogenous administration of erythropoietin to prevent RBC transfusions in critically ill patients. Studies vary with respect to rHuEPO dosage regimens, dose of concurrently administered iron, patient characteristics, and transfusion thresholds. Administration of rHuEPO rapidly produces erythropoiesis to reduce the need for RBC transfusions. The largest study conducted to date used weekly rHuEPO administration and found a modest decrease in transfusion requirements although the time to first transfusion was delayed. Reduced intensive care unit (ICU) length of stay (LOS) was shown in only one study of surgical/trauma patients. Reduced LOS after ICU discharge was found in another study of severely ill patients (APACHE II score >22). Other clinical outcomes were not altered by rHuEPO use. No adverse events were associated with rHuEPO use although studies were not designed to evaluate safety.

CONCLUSIONS

rHuEPO reduces the need for transfusions. A cost-effectiveness analysis of rHuEPO for this indication is needed. Defining an optimal dosage regimen, identifying patients most likely to respond to rHuEPO, and determining risk factors for ICU associated anaemia would provide information for appropriate rHuEPO utilization.

Phylogenetic origin of LI-cadherin revealed by protein and gene structure analysis

The intestine specific LI-cadherin differs in its overall structure from classical and desmosomal cadherins by the presence of seven instead of five cadherin repeats and a short cytoplasmic domain. Despite the low sequence similarity, a comparative protein structure analysis revealed that LI-cadherin may have originated from a five-repeat predecessor cadherin by a duplication of the first two aminoterminal repeats. To test this hypothesis, we cloned the murine LI-cadherin gene and compared its structure to that of other cadherins. The intron-exon organization, including the intron positions and phases, is perfectly conserved between repeats 3-7 of LI-cadherin and 1-5 of classical cadherins. Moreover, the genomic structure of the repeats 1-2 and 3-4 is identical for LI-cadherin and highly similar to that of the repeats 1-2 of classical cadherins. These findings strengthen our assumption that LI-cadherin originated from an ancestral cadherin with five domains by a partial gene duplication event.

Ksp-cadherin is a functional cell–cell adhesion molecule related to LI-cadherin

Ksp- and LI-cadherin are structurally homologous proteins coexpressed with E-cadherin in renal and intestinal epithelia, respectively. Whereas LI-cadherin has been shown to mediate Ca2+-dependent homotypic cell-cell adhesion independent of stable interactions with the cytoskeleton, little is known about the physiological role of Ksp-cadherin. To analyze its potential adhesive and morphoregulatory functions, we expressed murine Ksp-cadherin in CHO cells. In this report, we show that Ksp-cadherin induces homotypic and Ca2+-dependent cell-cell adhesion that can be specifically blocked with antibodies raised against the cadherin repeats EC1 and EC2. Ksp-cadherin mediates about the same quantitative adhesive effect (aggregation index) as LI- and E-cadherin. However, the cellular phenotype induced by Ksp-cadherin resembles more closely that of LI- than E-cadherin. This could reflect our observation, that Ksp-cadherin, as well as LI-cadherin, does not directly interact with beta-catenin. In conclusion, both cadherins are thus not only structurally but also functionally related and may share other functions within their respective epithelia.

Weight loss in obese diabetic and non-diabetic individuals and long-term diabetes outcomes--a systematic review

The aim was to review the evidence for the long-term effects of weight loss on diabetes outcomes in obese people or for those at risk of developing type 2 diabetes. Current evidence is mostly based on short-term studies. This is a systematic review of long-term outcomes of weight loss in studies published between 1966 and 2001. Eleven long-term studies with a follow up of more than 2 years were included. Results show that those with diabetes who lost weight intentionally significantly reduced their mortality risks by 25%. Additionally, weight loss of 9-13 kg was most protective. Patients with the risk of developing diabetes due to either family history of diabetes or impaired glucose tolerance, saw a reduction in this risk. Those with large weight losses achievable with surgical interventions reduced their risk by at least 63%. Metabolic handling of glucose improved in 80% of those already with type 2 diabetes who lost weight. Based on one large study, intentional weight loss in obese patients appears to have a beneficial effect on mortality risk for those with type 2 diabetes. Clearly, further studies are needed to endorse this. The risk of developing diabetes being reduced by weight loss was shown in seven studies. However, the results were from studies with different analytical adjustments and outcome indices, making it difficult to make direct comparisons and should be viewed with caution. More long-term prospective studies need to be conducted with commitment to improving the methodological quality and standardization, in order to accurately assess the long-term effects of weight loss for obese diabetic and non-diabetic individuals.

Effects of weight loss in overweight/obese individuals and long-term lipid outcomes--a systematic review

This paper aims to review the evidence for long-term effectiveness of weight loss on cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and triglycerides in overweight/obese people. Current evidence is mostly based on short-term studies. A systematic review of long-term lipid outcomes of weight loss in studies published between 1966 and 2001, was conducted. Inclusion criteria included all cohort studies and trials carried out on participants with body mass index of greater than or equal to 28 kg m(-2). Studies had at least two weight change measurements and follow-up of more than 2 years. Thirteen long-term studies with a follow-up of more than 2 years were included. Cholesterol has a significant positive linear relationship with weight change (r = 0.89) where change in weight explains about 80% of the cholesterol difference variation (Adj R2 = 0.80). For every 10 kg weight loss a drop of 0.23 mmol L(-1) in cholesterol may be expected for a person suffering from obesity or are grossly overweight. Weight loss has long-term beneficial effects especially on LDL and cholesterol. Weight loss in obese patients should be encouraged and sustained.

Duration of antimicrobial therapy for nosocomial pneumonia: possible strategies for minimizing antimicrobial use in intensive care units

OBJECTIVE

To review published data evaluating shorter courses of antibiotic therapy for nosocomial pneumonia and provide recommendations for minimizing antimicrobial use in intensive care units.

DATA SOURCE

Literature was identified through MEDLINE (1966 through 6/2002) and a manual search of critical care, infectious disease, and pharmacy journals was conducted to identify relevant abstracts.

DATA SYNTHESIS

Antibiotic use may be decreased by discontinuing therapy after 3 days in patients with low likelihood of nosocomial pneumonia. In addition, clinical guidelines or invasive diagnostic procedures may be effectively instituted to reduce duration of antibiotic therapy.

CONCLUSION

Shorter-course antibiotic therapy may be beneficial in decreasing lengths of hospital and intensive care units stays, antimicrobial resistance, and total hospital costs. Further research is needed to determine the optimal duration of therapy in patients with nosocomial pneumonia.

A method for assessing balance control in rodents

Recent research has shown that after spinal cord injury, the nervous system reorganizes. Nevertheless, little is known of the effects of neural reorganization, or plasticity, on motor skills. In this work, we present a method that utilizes kinetic and kinematic analysis, for investigating balance control in a rodent model of incomplete spinal cord injury. In this setup, the animals sit unconstrained on their hindlimbs on a platform while they eat a Fruitloop. In this posture, the animal is supporting all the body weight on its hindquarters removing the need for the animal to support itself on its hindlimb or maintain appropriate forelimb-hindlimb coordination for functional gait. The platform is bolted to a force transducer to provide measurements of shear forces in orthogonal directions in the horizontal plane. Reflective markers on the hip and tail of the animal indicate sway of the animals body. Using this method the effect of extensive 12 week long treadmill locomotor training on balance control in rodents with incomplete thoracic spinal cord contusion injury (iSCI) was assessed. One iSCI rat did not undergo training, while a sham injured and 3 other iSCI rats underwent training. The shear forces and sway produced by the injured untrained rat were much larger than for the sham or the injured but trained rats. Stance width assessed from overground walking in a separate study was also larger in the injured untrained rat. These data suggest that balance control may be improved by a locomotor training paradigm. This simple method for assessing balance control could thus be utilized in longitudinal studies to evaluate the effectiveness of pharmacological and locomotor therapies for repair and recovery after spinal cord injury.

Tracking rhythmicity in nonstationary quasi-periodic biomedical signals using adaptive time-varying covariance

A time-varying covariance method for detecting and quantifying the evolution of rhythmicity (frequency) in persistently varying quasi-periodic nonstationary signals is presented. The basic method, evaluated using chirp signals, utilizes a shifting window of fixed length. A substantial reduction in estimation bias and variability are obtained by utilizing an adaptive window whose length is dependent on past frequency estimates. The adaptive window yields estimates that are comparable in accuracy to those obtained using high-resolution time-frequency representation but with lower computation requirements and the potential for on-line application. Finally, an example of the application of the method for analyzing a neural recording is also illustrated.

Variability analyses suggest that supraspino-spinal interactions provide dynamic stability in motor control

Effects of supraspino-spinal feedforward-feedback (FF-FB) interactions on variability in locomotor rhythm and coordination were examined in in vitro brain-spinal cord lamprey preparations. Spinal locomotor networks were activated by applying 0.2 mM N-methyl-DL-aspartate (NMA) to three spinal pools: gill, rostral and caudal. Bathing the brain with zero Ca(2+) saline altered supraspinal-spinal drive and FF-FB interaction while spino-supraspinal feedback was changed by applying NMA to the caudal pool only. Wavelet analyses indicated a non-uniform energy distribution in ventral root (VR) activity that shifted between frequency bands on FF-FB interruption. Wavelet analysis was used to extract 300-s long epochs of low frequency burst rhythm. These were analyzed using a sliding-window time-varying covariance method. From the autocovariance in each window, the cycle period and height of the first side lobe peak were determined. Rostral VR variability (determined from standard deviation and coefficient of variation of all cycle periods and the mean peak height) was significantly higher than caudal VR variability. FF-FB interruption significantly decreased the rostral VR cycle period and variability but the rostro-caudal gradient remained. The intersegmental delay was also affected. The caudal VR rhythm with NMA in the caudal pool only was slower but more variable than with NMA over the entire cord. These results indicate that the locomotor rhythm in the presence of supraspino-spinal interactions is slower but has a higher variability. The higher variability may reflect a dynamic stability of the system. Additionally, differences in local neural organization likely contribute to rostro-caudal differences in variability of the motor output.

Interference of cytokeratin-20 and mammaglobin-reverse-transcriptase polymerase chain assays designed for the detection of disseminated cancer cells

Several reverse-transcriptase polymerase chain reaction (rtPCR) assays have been designed for the detection of disseminated cancer cells. The specificity of these discussed molecular approaches is controversial. Biological interference of the cytokeratin-20 and mammaglobin rtPCR assays has been investigated. Cell lines of different lineages and bone marrow and peripheral stem cells from patients without epithelial cancer have been examined for the transcription of the cytokeratin-20 (CK20) and mammaglobin messages prior to and after stimulation with different cytokines in a total of 370 liquid cultures. Amplification of both messages from clinical samples prior to stimulation does not support the high specificity for the detection of disseminated epithelial cancer cells as reported. Cytokeratin-20 was amplified from the chronic myeloic leukemia (CML)-derived line K562. Transcription was not influenced by cytokines, either in cell-line experiments or in clinical samples. The thesis of a low-level background transcription in granulocytes is supported. Mammaglobin was induced in cell lines significantly by GM-CSF and in clinical samples additionally by several more cytokines. These results indicate that under certain conditions involving cytokine production, the use of mammaglobin rtPCR for the detection of epithelial cancer cells could be limited. In conclusion, the mechanism of interference of both rtPCR assays are completely different and further research is necessary before the cytokeratin-20 or mammaglobin rtPCR could become standard methods for the detection of disseminated epithelial cancer cells. These factors leading to so-called false-positive results have to be considered in future applications of rtPCR for the detection of minimal residual disease.

Genomics analysis of genes expressed in maize endosperm identifies novel seed proteins and clarifies patterns of zein gene expression

We analyzed cDNA libraries from developing endosperm of the B73 maize inbred line to evaluate the expression of storage protein genes. This study showed that zeins are by far the most highly expressed genes in the endosperm, but we found an inverse relationship between the number of zein genes and the relative amount of specific mRNAs. Although alpha-zeins are encoded by large multigene families, only a few of these genes are transcribed at high or detectable levels. In contrast, relatively small gene families encode the gamma- and delta-zeins, and members of these gene families, especially the gamma-zeins, are highly expressed. Knowledge of expressed storage protein genes allowed the development of DNA and antibody probes that distinguish between closely related gene family members. Using in situ hybridization, we found differences in the temporal and spatial expression of the alpha-, gamma-, and delta-zein gene families, which provides evidence that gamma-zeins are synthesized throughout the endosperm before alpha- and delta-zeins. This observation is consistent with earlier studies that suggested that gamma-zeins play an important role in prolamin protein body assembly. Analysis of endosperm cDNAs also revealed several previously unidentified proteins, including a 50-kD gamma-zein, an 18-kD alpha-globulin, and a legumin-related protein. Immunolocalization of the 50-kD gamma-zein showed this protein to be located at the surface of prolamin-containing protein bodies, similar to other gamma-zeins. The 18-kD alpha-globulin, however, is deposited in novel, vacuole-like organelles that were not described previously in maize endosperm.

Genomics analysis of genes expressed in maize endosperm identifies novel seed proteins and clarifies patterns of zein gene expression

We analyzed cDNA libraries from developing endosperm of the B73 maize inbred line to evaluate the expression of storage protein genes. This study showed that zeins are by far the most highly expressed genes in the endosperm, but we found an inverse relationship between the number of zein genes and the relative amount of specific mRNAs. Although alpha-zeins are encoded by large multigene families, only a few of these genes are transcribed at high or detectable levels. In contrast, relatively small gene families encode the gamma- and delta-zeins, and members of these gene families, especially the gamma-zeins, are highly expressed. Knowledge of expressed storage protein genes allowed the development of DNA and antibody probes that distinguish between closely related gene family members. Using in situ hybridization, we found differences in the temporal and spatial expression of the alpha-, gamma-, and delta-zein gene families, which provides evidence that gamma-zeins are synthesized throughout the endosperm before alpha- and delta-zeins. This observation is consistent with earlier studies that suggested that gamma-zeins play an important role in prolamin protein body assembly. Analysis of endosperm cDNAs also revealed several previously unidentified proteins, including a 50-kD gamma-zein, an 18-kD alpha-globulin, and a legumin-related protein. Immunolocalization of the 50-kD gamma-zein showed this protein to be located at the surface of prolamin-containing protein bodies, similar to other gamma-zeins. The 18-kD alpha-globulin, however, is deposited in novel, vacuole-like organelles that were not described previously in maize endosperm.