Impact of pH on the viability and morphology of Blastocystis isolates

Blastocystis sp. is ubiquitous in avian, mammalian and human hosts and propagates in either neutral or slightly alkaline conditions within the host's gastro-intestinal tract. Of the few previous studies on this enteric protozoan parasite in feline and canine hosts, prevalence values have been shown to range between 0 to 70.8%. In view of the close association between humans, and canine and feline hosts as companion animals, faecal samples of 180 Felis catus and 82 Canis lupus, collected from Penang and Kuala Lumpur, Malaysia, were initially screened by in vitro cultivation followed by molecular characterization. No positive isolates were identified in culture but in 12 feline samples DNA barcoding detected a zoonotic subtype Blastocystis ST1 for the first time. Consequently, avian and human isolates, which had previously been successfully cultured, were used to investigate the impact of pH on the viability and morphology of Blastocystis sp. The use of Trypan blue showed that the number of viable cells increased when exposed to pH 4 and a significant increase in viability occurred in pH values of 5 to 7. Development of Blastocystis cells in both isolates was suppressed in media less than pH 5 followed by the disappearance of viable cells from avian isolates in more acidic media below pH 4. Morphologically at pH 4 cells from avian isolates were less rounded, and with wrinkled / shrunken surfaces, than the more normal rounded cells from human isolates. On the other hand, at values below pH 3, no viable cells in human isolates were visible. The present findings therefore confirm that gastro-intestinal pH is an important determinant of Blastocystis viability and consequently influences the epidemiology of infection within avian, mammalian and human hosts.

Comparing accelerometer, pedometer and a questionnaire for measuring physical activity in bronchiectasis: a validity and feasibility study?

Background

There are challenges for researchers and clinicians to select the most appropriate physical activity tool, and a balance between precision and feasibility is needed. Currently it is unclear which physical activity tool should be used to assess physical activity in Bronchiectasis. The aim of this research is to compare assessment methods (pedometer and IPAQ) to our criterion method (ActiGraph) for the measurement of physical activity dimensions in Bronchiectasis (BE), and to assess their feasibility and acceptability.

Methods

Patients in this analysis were enrolled in a cross-sectional study. The ActiGraph and pedometer were worn for seven consecutive days and the IPAQ was completed for the same period. Statistical analyses were performed using SPSS 20 (IBM). Descriptive statistics were used; the percentage agreement between ActiGraph and the other measures were calculated using limits of agreement. Feedback about the feasibility of the activity monitors and the IPAQ was obtained.

Results

There were 55 (22 male) data sets available. For step count there was no significant difference between the ActiGraph and Pedometer, however, total physical activity time (mins) as recorded by the ActiGraph was significantly higher than the pedometer (mean ± SD, 232 (75) vs. 63 (32)). Levels of agreement between the two devices was very good for step count (97% agreement); and variation in the levels of agreement were within accepted limits of ±2 standard deviations from the mean value.

IPAQ reported more bouted- moderate - vigorous physical activity (MVPA) [mean, SD; 167(170) vs 6(9) mins/day], and significantly less sedentary time than ActiGraph [mean, SD; 362(115) vs 634(76) vmins/day]. There were low levels of agreement between the two tools (57% sedentary behaviour; 0% MVPA₁₀₊), with IPAQ under-reporting sedentary behaviour and over-reporting MVPA₁₀₊ compared to ActiGraph. The monitors were found to be feasible and acceptable by participants and researchers; while the IPAQ was accepta ble to use, most patients required assistance to complete it.

Conclusions

Accurate measurement of physical activity is feasible in BE and will be valuable for future trials of therapeutic interventions. ActiGraph or pedometer could be used to measure simple daily step counts, but ActiGraph was superior as it measured intensity of physical activity and was a more precise measure of time spent walking. The IPAQ does not appear to represent an accurate measure of physical activity in this population.

Trial registration

Clinical Trials Registration Number NCT01569009: Physical Activity in Bronchiectasis.

Application of ion exchange and extraction chromatography to the separation of actinium from proton-irradiated thorium metal for analytical purposes

Actinium-225 (t1/2=9.92d) is an α-emitting radionuclide with nuclear properties well-suited for use in targeted alpha therapy (TAT), a powerful treatment method for malignant tumors. Actinium-225 can also be utilized as a generator for (213)Bi (t1/2 45.6 min), which is another valuable candidate for TAT. Actinium-225 can be produced via proton irradiation of thorium metal; however, long-lived (227)Ac (t1/2=21.8a, 99% β(-), 1% α) is co-produced during this process and will impact the quality of the final product. Thus, accurate assays are needed to determine the (225)Ac/(227)Ac ratio, which is dependent on beam energy, irradiation time and target design. Accurate actinium assays, in turn, require efficient separation of actinium isotopes from both the Th matrix and highly radioactive activation by-products, especially radiolanthanides formed from proton-induced fission. In this study, we introduce a novel, selective chromatographic technique for the recovery and purification of actinium isotopes from irradiated Th matrices. A two-step sequence of cation exchange and extraction chromatography was implemented. Radiolanthanides were quantitatively removed from Ac, and no non-Ac radionuclidic impurities were detected in the final Ac fraction. An (225)Ac spike added prior to separation was recovered at ≥ 98%, and Ac decontamination from Th was found to be ≥ 10(6). The purified actinium fraction allowed for highly accurate (227)Ac determination at analytical scales, i.e., at (227)Ac activities of 1-100 kBq (27 nCi to 2.7 μCi).

Cross-relaxation imaging of human patellar cartilage in vivo at 3.0T

OBJECTIVE

To compare quantitative magnetization transfer (qMT) parameters of patellar cartilage measured using cross-relaxation imaging (CRI) in asymptomatic volunteers and patients with osteoarthritis.

DESIGN

The study was performed with Institutional Review Board approval and with all subjects signing informed consent. CRI of the knee joint was performed at 3.0T on 20 asymptomatic volunteers and 11 patients with osteoarthritis. The fraction of macromolecular bound protons (f), the exchange rate constant between macromolecular bound protons and free water protons (k), and the T2 relaxation time of macromolecular bound protons (T2(B)) of patellar cartilage were measured. Mann-Whitney-Wilcoxon rank-sum tests were used to compare qMT parameters between asymptomatic volunteers and patients with osteoarthritis.

RESULTS

Average f, k, and T2(B) of patellar cartilage was 12.46%, 7.22 s(-1), and 6.49 μs respectively for asymptomatic volunteers and 12.80%, 6.13 s(-1), and 6.80 μs respectively for patients with osteoarthritis. There were statistically significant differences between groups of subjects for k (P < 0.01) and T2(B) (P < 0.0001) but not f (P = 0.38) of patellar cartilage.

CONCLUSION

Patients with osteoarthritis had significantly lower k and significantly higher T2(B) of patellar cartilage than asymptomatic volunteers which suggests that qMT parameters can detect changes in the macromolecular matrix of degenerative cartilage.

Attention deficit hyperactivity disorder (ADHD) and substance use disorders

Attention deficit hyperactivity disorder (ADHD) is a common childhood disorder that often continues to manifest symptoms into adulthood. In children and adults, this condition may contribute to addictive vulnerability. Several factors are common to the developmental psychopathology of these conditions, suggesting an underlying deficit in behavioral regulation as an explanation for this comorbidity. Developmentally, faulty learning processes or attempts to self-medicate dysfunctional behavior may contribute to the pathogenesis of substance use disorders. Substance abuse itself also may contribute to the development of attentional deficits and behavioral dysregulation through direct (eg, prenatal or self-inflicted exposures to neurotoxic substances) and indirect (eg, poverty, neglect, abuse) mechanisms. Because ADHD can be identified prior to the peak onset of substance use, effective treatment of this common disorder may reduce the development of substance use disorders. Adult ADHD may also contribute to the development and maintenance of substance use disorders Substance abuse patients may particularly benefit from treatment of this comorbidity.

Investigating hepatitis C virus heterogeneity in a high prevalence setting using heteroduplex tracking analysis

Hepatitis C virus (HCV) infection is very common among chronic hemodialysis patients. In the past, blood transfusion appeared to be the primary risk factor; however evidence of nosocomial HCV transmission in the hemodialysis setting has recently been reported. This report describes a molecular investigation of HCV isolates obtained from a population of 670 patients attending six different Seattle-King County based hemodialysis centers in order to identify potential common source infections. 733 serum specimens were collected from hemodialysis patients in 1992 and 1996, and were tested for HCV antibodies and RNA. Overall, 115 of 670 (17%) patients were positive for HCV RNA, and thus were considered actively infected by HCV. HCV genotype was determined in all cases by restriction fragment length polymorphism, and 93 patients were found to be infected by HCV genotype 1. HCV envelope genes were amplified from the 93 patients with genotype 1 infection, and were studied in further detail by heteroduplex tracking analysis (HTA) using genotype 1a and 1b specific probes derived from the envelope 1 (E1) and envelope 2 (E2) genes. Genetic relatedness between pairs of HCV envelope genes was estimated by calculating the degree of gel shift relative to homoduplex controls. Nucleotide sequencing and phylogenetic analysis was used to confirm genetic relatedness detected by HTA. When HTA was performed using the E1 gene probe, 12 apparently related infections were detected; 10 of 12 (83%) of these infections were confirmed as truly related using the gold standard method of nucleotide sequencing plus phylogenetic analysis. Using an E2 gene probe, 24 infections were apparently related, but only six (25%) were confirmed by sequencing. As a control, 41 envelope genes, which were unrelated by HTA, were sequenced; 0 of 41 (0%) were truly related. In summary, HTA provides a rapid and effective molecular technique for screening HCV genetic relatedness in population-based studies, and should prove valuable in future studies of HCV molecular epidemiology.

Substance abuse and criminal recidivism: a prospective study of adolescents

Studies of substance abuse among delinquents have shown mixed results on criminal recidivism. The present study evaluates personality traits associated with substance abuse and recidivism among delinquent boys, and prospectively determines the extent to which these factors are predictive of criminal recidivism. 134 incarcerated boys (x = 15.9 +/- 1.1) completed the Weinberger Adjustment Inventory and the Substance Abuse Screening Inventory. Youth were prospectively followed for up to 4.5 years following release. Among incarcerated delinquents, personality traits are predictive of a positive substance abuse screen and recidivism. A trend indicating a possible interaction between personality and treatment is observed. If these findings are replicated, personality traits may play a role in predicting substance abuse as well as individual delinquent responses to treatment.

Differential regulation of mammalian brain-specific proline transporter by calcium and calcium-dependent protein kinases

1. This study examined the role of [Ca2+]I and Ca(2+)-dependent kinases in the modulation of high-affinity, mammalian brain-specific L-proline transporter (PROT). 2. beta-PMA (phorbol 12-myristate 13-acetate), an activator of protein kinase C (PKC), inhibits PRO uptake, and bisindolymalemide I (BIM), a potent PKC inhibitor, prevents beta-PMA inhibition. Down-regulation of PKC by chronic treatment with beta-PMA enhances PROT function indicating PROT regulation by tonic activity of PKC. 3. Thapsigargin, which increases [Ca2+]I levels by inhibiting Ca(2+)-ATPase, inhibits PROT and exhibits additive inhibition when co-treated with beta-PMA. KN-62, a Ca2+/calmodulin-dependent kinase II (CaMK II) inhibitor, but not BIM (a PKC inhibitor) prevents the inhibition by thapsigargin. These data suggest that PKC and CaMK II modulate PROT and that thapsigargin mediates its effect via CaMK II. 4. Thapsigargin raises [Ca2+]I and increases PRO-induced current on a second time scale, whereas the inhibitory effect of thapsigargin occurs only after 10 min of treatment. These data suggest that Ca2+ differentially regulate PROT: Ca2+ initially enhances PRO transport but eventually inhibits transport function through CaMK II pathway. 5. Ca(2+)-induced stimulation exemplifies the acute regulation of a neurotransmitter transporter, which may play a critical role in the profile of neurotransmitters during synaptic transmission.

Relationship between iron concentration and hepatitis C virus RNA level in liver tissue

Patients with chronic hepatitis C virus (HCV) infection frequently have increased hepatic iron stores. The role of hepatitis C in hepatic iron deposition is unknown. The authors examined whether there is a relation between hepatitis C virus level in liver tissue and hepatic iron concentration. Forty-two paired samples obtained from the liver explants of five patients who underwent transplantation for liver disease due to hepatitis C were studied. Hepatitis C virus levels were measured at multiple sites within each liver by a branched deoxyribonucleic assay. Measurements of hepatic iron concentration were made at adjacent sites by a colorimetric assay. Random effects modeling showed wide intrahepatic variation in hepatic HCV ribonucleic acid (RNA) concentration (variance = 1.2 x 10(4) [mEq/g]2) and hepatic iron concentration (variance = 1.3 x 10(6) [microg/g]2). There was, however, a trend toward an association between the mean HCV level and the mean hepatic iron concentration for each liver (r = 0.30, p = 0.05). In conclusion, HCV level and iron concentration varied within and between cirrhotic livers. Variability in intrahepatic iron concentration was not related to variability in intrahepatic HCV RNA concentration. More studies are needed to determine the cause of variability in hepatic iron and HCV RNA concentration within and between livers in patients with chronic hepatitis C.

Homeopathy in rehabilitation medicine

Rehabilitationists must be able to assess not only the diagnostic entity, but also the person who is sick. The rehabilitation community's understanding of the holism involved in healing and the limitations of conventional therapies creates an openness to consider the usefulness of unconventional therapies. This article explores the role of homeopathy in rehabilitation medicine.

Multigene tracking of hepatitis C virus quasispecies after liver transplantation: correlation of genetic diversification in the envelope region with asymptomatic or mild disease patterns

To investigate the role of hepatitis C virus (HCV) quasispecies mutation in the pathogenesis of HCV infection, we analyzed changes in the genetic diversity of HCV genomes in 22 patients before and after liver transplantation by using heteroduplex mobility assay (HMA) technology. All patients were infected with HCV genotype 1 and developed high-titer posttransplant viremia. Each patient was classified according to the severity of posttransplant hepatitis, as assessed by standard biochemical and histological criteria. HCV quasispecies were characterized by HMA analysis of eight separate subgenomic regions of HCV, which collectively comprise 44% of the entire genome. The glycoprotein genes E1 and E2, as well as the nonstructural protein genes NS2 and NS3, had the greatest genetic divergence after liver transplantation (the change in the heteroduplex mobility ratio [HMR] ranged from 2.5 to 7.0%). In contrast, genes encoding the core, NS4, and NS5b proteins had the least amount of genetic divergence after liver transplantation (range, 0.3 to 1.2%). The E1/E2 region showed the greatest change in genetic diversity after liver transplantation, and the change in HMRs was 2.5- to 3.3-fold greater in patients with asymptomatic or moderate disease than in those with severe disease. The E1-5' region of HCV quasispecies isolated from patients in the asymptomatic group had a significantly greater degree of diversification after liver transplantation than the same regions of HCV quasispecies isolated from patients in the severe disease group (P = 0.05). While changes in the genetic diversity of some nonstructural genes were also greater in asymptomatic patients or in patients with mild disease than in patients with severe disease, the results were not significant. Data from this cohort demonstrate that greater rates of HCV quasispecies diversification are associated with mild or moderate liver disease activity in this immunosuppressed population.

Na+-coupled alanine transport in LLC-PK1 cells: the relationship between the Km for Na+ at low [Alanine] and potential dependence for the system

Analysis of the mechanistic basis by which sodium-coupled transport systems respond to changes in membrane potential is inherently complex. Algebraic expressions for the primary kinetic parameters (Km and Vmax) consist of multiple terms that encompass most rate constants in the transport cycle. Even for a relatively simple cotransport system such as the Na+/alanine cotransporter in LLC-PK1 cells (1:1 Na+ to substrate coupling, and an ordered binding sequence), the algebraic expressions for Km for either substrate includes ten of the twelve rate constants necessary for modeling the full transport cycle. We show here that the expression of Km of the first-bound substrate (Na+) simplifies markedly if the second-bound substrate (alanine) is held at a low concentration so that its' binding becomes the rate limiting step. Under these conditions, the expression for the KNam includes rate constants for only two steps in the full cycle: (i) binding/dissociation of Na+, and (ii) conformational 'translocation' of the substrate-free protein. The influence of imposed changes in membrane potential on the apparent KNam for the LLC-PK1 alanine cotransporter at low alanine thus provides insight to potential dependence at these sites. The data show no potential dependence for KNam at 5 micron alanine, despite marked potential dependence at 2 mm alanine when the full algebraic expression applies. The results suggest that neither translocation of the substrate-free form of the transporter nor binding/dissociation of extracellular sodium are potential dependent events for this transport system.

Coping strategies and laboratory pain in children with sickle cell disease

Studies have found that coping strategies are significant predictors of pain report, health care use, and psychosocial adjustment in children with sickle cell disease (SCD); however, the mechanisms of the relationship are not clear. In this study, 41 children with SCD completed a laboratory pain task to analyze their pain perception under standardized conditions. Sensory decision theory analyses were used to analyze the pain perception data. Children and their parents also completed measures of coping strategies and adjustment. Hierarchical regression analyses controlling for the child's age indicated that children who reported using active cognitive and behavioral coping strategies had a lower tendency to report pain during the laboratory pain task. Results are discussed in terms of the utility of using laboratory pain models with children and the need for future intervention studies to target coping strategies in children with SCD pain.

Oceanographic lidar attenuation coefficients and signal fluctuations measured from a ship in the Southern California Bight

We measured the attenuation coefficient of the National Oceanic and Atmospheric Administration lidar from a ship in the Southern California Bight in September 1995. The region from approximately 5 to 30 m in depth was covered. The laser was linearly polarized, and the receiver was operated with the same polarization and the orthogonal polarization. The measured values were between 0.08 and 0.12 m(-1) and were highly correlated with in situ measurements of the beam attenuation coefficient. Fluctuations of the lidar signal were found to be induced primarily by surface waves whose wavelengths are approximately three times the lidar spot size at the surface.

Starvation depresses acylglycerol biosynthesis in bovine subcutaneous but not intramuscular adipose tissue homogenates

The primary objective of this study was to document the effects of starvation on acylglycerol biosynthesis in homogenates of intramuscular and subcutaneous adipose tissues. Adipose tissue samples were obtained from 8th-13th thoracic rib sections from 12 Angus cattle (six steers plus six heifers). Three steers and three heifers were starved for 72 h prior to slaughter while the remainder were slaughtered 4 h after food was withheld. Fat-free 700 x g centrifugal fractions were used to measure the esterification of radiolabeled sn-glycerol 3-phosphate (G-3-P) into acylglycerols at 1.0 mM palmitic or stearic acid, or 0.2 mM oleic, linoleic, or alpha-linolenic acid. There were significant tissue x fatty acid interactions for rates of incorporation into diacylglycerols and triacylglycerols; in subcutaneous, but not intramuscular homogenates, palmitic > stearic = oleic = linoleic = alpha-linolenic acid. Subcutaneous homogenates incorporated a greater percentage of G-3-P into triacylglycerols, and a lesser percentage into phospholipid, than intramuscular homogenates (P < 0.05). In intramuscular homogenates, the primary product of G-3-P esterification to saturated fatty acids was phospholipids. When unsaturated fatty acid served as substrates, triacylglycerols and phospholipids were produced in equal proportions in intramuscular homogenates, and triacylglycerols were the predominant product in subcutaneous homogenates. Intramuscular adipose tissue homogenates exhibited no response to starvation, whereas triacylglycerol and diacylglycerol synthesis was depressed by approximately 50% in subcutaneous adipose tissue homogenates. Similarly, phosphatidic phosphohydrolase activity, initially greater in subcutaneous than in intramuscular adipose tissue, was decreased by approximately 50% by starvation in subcutaneous adipose tissue, but not in intramuscular adipose tissue. We conclude that differences in rates of diacylglycerol and triacylglycerol biosynthesis, and response to starvation, between intramuscular and subcutaneous adipose tissues were due to dissimilarities in the activity of phosphatidic phosphohydrolase.

Cognitive coping skills training in children with sickle cell disease pain

This study was designed to examine whether brief training in cognitive coping skills would enhance pain coping strategies and alter pain perception in children and adolescents with sickle cell disease (SCD). Forty-nine participants with SCD were randomly assigned to either a cognitive coping skills condition or a standard care control condition. At pre- and posttesting, coping strategies and pain sensitivity using laboratory pain stimulation were measured. Results indicated that in comparison to the randomly assigned control condition, brief training in cognitive coping skills resulted in decreased negative thinking and lower pain ratings during low intensity laboratory pain stimulation.

Lidar profiles of fish schools

A lidar system was used in a seawater tank to measure the average diffuse reflectivity of live sardines. Diffuse reflectivity was measured to be 10 % for a copolarized laser return and 3 % for a cross-polarized return. We used these calibration measurements to infer the density of sardines in areas of the Southern California Bight from vertical profiles obtained with the lidar mounted on a ship. Within schools densities up to ~0.01 kg m-3 were observed. During hourly survey periods total habitat densities up to ~2 x10-3 kg m-2 were observed.

The stability of pain coping strategies in young children adolescents, and adults with sickle cell disease over an 18-month period

OBJECTIVE

The current study assessed stability of pain coping strategies over an 18-month period in adults, adolescents, and young children with sickle cell disease.

DESIGN

Eighteen-month longitudinal study. Assessments of coping strategies were done at baseline, 9 months, and 18 months.

PATIENTS

A total of 141 patients with sickle cell disease (SCD) presenting to adult and pediatric sickle cell clinics for regularly scheduled check-ups.

OUTCOME MEASURES

Coping Strategy Questionnaire subscales (Coping Attempts, Negative Thinking, and Illness-Focused Strategies).

RESULTS

pearson Product-Moment correlation coefficients comparing baseline and 18-month follow-up coping data were highly significant for Coping Attempts and Negative Thinking/Illness Focused Strategies for adults. For young children, the 18-month follow-up scores on Negative Thinking were significantly correlated with baseline scores, however, no other 18-month correlations were significant. The results from the adolescent subset of subjects indicated no significant correlations on any of the coping strategies from baseline to 18-month-follow-up. Stability was also assessed using intraclass correlations, which incorporates more than two test-retest values on the same subjects. These analyses confirmed that coping strategies in adults were highly stable, whereas for children and adolescents, there was instability ANOVAs indicated that adolescents scored significantly higher than young children on Negative Thinking and Illness-Focused Strategies at baseline and follow-up.

CONCLUSIONS

As compared with the highly stable coping evidenced in adults with SCD, coping in children and adolescents with SCD is more variable. Thus, interventions should target children early before maladaptive coping patterns become entrenched.

Cyclophosphamide and fluorouracil combined with mitoxantrone versus doxorubicin for breast cancer: superiority of doxorubicin

PATIENTS AND METHODS

We conducted a randomized, multicenter study of intravenous cyclophosphamide 500 mg/m2 plus fluorouracil 500 mg/m2 combined with either mitoxantrone (Novantrone, Lederle Cyanamid Canada Ltd, Willowdale, Ontario) 10 mg/m2 (CNF) or doxorubicin (Adriamycin, Adria Laboratories of Canada Ltd, Mississauga, Ontario) 50 mg/m2 (CAF) every 3 weeks in advanced breast cancer.

RESULTS

The response rate in 249 randomized patients was 36% with CNF (44 of 121) and 48% with CAF (62 of 128) (P = .054), with complete remissions in 10 patients (8.3%) on CNF and in 13 (10.2%) on CAF. If only fully assessable patients are considered, the response rate was 48% (44 of 91) with CNF and 60% (62 of 103) with CAF (P = .098). At time of analysis, all except 10 patients (one CNF and nine CAF) had died. The median survival time with CAF was longer than with CNF (15.2 v 10.9 months; P = .003), and time to progression was also longer with CAF (5.3 v 3.2 months; P < .03). Survival differences remained significant (P = .006) if patients who failed to meet all eligibility criteria were excluded. Favorable prognostic factors for survival in a Cox regression model included good performance status (P < .0001); less than two organ systems involved by tumor (P < .0001); no involvement of lung, liver, or brain (P < .003); involvement of bone or bone marrow (P < .009), prior surgery for breast cancer (P < .006); being premenopausal (P < .03); > or = 3 years from diagnosis until randomization on this study (P < .03); and treatment with CAF (P < .03). Alopecia > or = grade 3 was reported in 55% of patients with CAF and 12% of patients with CNF (P < .001), while other > or = grade 3 toxicities did not differ significantly. Priestman-Baum quality-of-life assessment was comparable on the two study arms.

CONCLUSION

In patients with advanced breast cancer, CAF was associated with longer survival than was CNF, with an increase in alopecia, but not in other toxicities.

Tracking hepatitis C virus quasispecies major and minor variants in symptomatic and asymptomatic liver transplant recipients

To evaluate the possibility that distinct viral quasispecies play a role in the pathogenesis of progressive hepatitis C virus (HCV) infection, we performed a detailed evaluation of HCV quasispecies before and after liver transplantation in five patients infected with HCV genotype 1, three of whom developed severe recurrent hepatitis C and two of whom developed asymptomatic posttransplant infections with high-titered viremia. HCV quasispecies were characterized by using a combination of nucleotide sequencing plus heteroduplex tracking assay of the second envelope gene hypervariable region (HVR). An average of 30 HVR clones were analyzed per specimen; an average of five specimens were analyzed per patient over a 6- to 24-month study period. The complexity of HCV quasispecies in pretransplant serum varied, ranging from one to nine genetically distinct variants for the five patients. However, in all five cases, relatively homogenous quasispecies variants emerged after liver transplantation. In the three patients who developed recurrent hepatitis, quasispecies major variants present in pretransplant serum were efficiently propagated immediately after liver transplantation and were propagated throughout the course of acute and chronic hepatitis. In contrast, in the two asymptomatic cases, we observed rapid depletion of pretransplant quasispecies major variants from posttransplant serum, followed by emergence of new quasispecies variants by posttransplant day 30. Genetic analysis suggested that in these cases, the new quasispecies variants were derived from minor variants present at relatively low clonal frequency (less than 5% of HVR clones) within the pretransplant quasispecies populations. These data demonstrate that quasispecies tracking patterns are associated with the rapidity and severity of HCV-associated liver disease after liver transplantation. Further characterization of HCV quasispecies in animal model systems is warranted.

Effects of cognitive coping skills training on coping strategies and experimental pain sensitivity in African American adults with sickle cell disease

The present study examined whether training in cognitive coping skills would enhance pain coping strategies and alter pain perception in adults with sickle cell disease (SCD). Sixty-four African Americans with SCD were randomly assigned to either a cognitive coping skills condition (three 45-min sessions in which patients were trained to use 6 cognitive coping strategies) or a disease-education control condition (three 45-min didactic-discussion sessions about SCD). Pain sensitivity to calibrated noxious stimulation was measured at pre- and posttesting, as were cognitive coping strategies, clinical pain, and health behaviors. Results indicated that, compared with the randomly assigned control condition, brief training in cognitive coping skills resulted in increased coping attempts, decreased negative thinking, and lower tendency to report pain during laboratory-induced noxious stimulation.

Suppression of renal gamma-glutamylcysteine synthetase expression in dietary copper deficiency

A dietary deficiency of copper (CuD) is associated with a 50-70% and a 2-fold increase in hepatic reduced glutathione (GSH) concentration and synthesis, respectively, which leads to a 50-80% increase in plasma GSH. Moreover, the kidneys of CuD rats remove 40% more GSH from the blood than copper adequate (CuA) rats. These findings have led us to propose that the increase in hepatic synthesis of GSH in CuD rats is accompanied by a comparable increase in the hepatic expression of gamma-glutamylcysteine synthetase (gamma-GCS), the rate limiting enzyme of glutathione biosynthesis, and that the enhanced uptake of GSH by the kidney would lead to a compensatory decrease in renal gamma-GCS expression. In experiment I, male weanling rats (3-4 weeks) were ad libitum fed a CuD (0.5 microgram Cu/g) or CuA (5.8 micrograms/g) diet for 70 days; and in experiment II, male weanling rats were pair-meal fed the CuD or CuA diet for 35 days. In both studies, CuD diet caused a significant increase in hepatic GSH concentration, but hepatic gamma-GCS activity and mRNA abundance were unchanged. In contrast, renal GSH concentration was unaffected by the CuD diet. However, renal gamma-GCS activity was reduced 40% and this was paralleled by a 50% decrease in gamma-GCS mRNA. Moreover, the decrease in renal gamma-GCS mRNA was caused by a reduction in renal gamma-GCS gene transcription. The results of these studies indicate that the increase in renal uptake of GSH resulting from a dietary Cu deficiency is associated with a compensatory decrease in gamma-GCS expression.

Chemotherapy with mitoxantrone plus prednisone or prednisone alone for symptomatic hormone-resistant prostate cancer: a Canadian randomized trial with palliative end points

PURPOSE

To investigate the benefit of chemotherapy in patients with symptomatic hormone-resistant prostate cancer using relevant end points of palliation in a randomized controlled trial.

PATIENTS AND METHODS

We randomized 161 hormone-refractory patients with pain to receive mitoxantrone plus prednisone or prednisone alone (10 mg daily). Nonresponding patients on prednisone could receive mitoxantrone subsequently. The primary end point was a palliative response defined as a 2-point decrease in pain as assessed by a 6-point pain scale completed by patients (or complete loss of pain if initially 1 +) without an increase in analgesic medication and maintained for two consecutive evaluations at least 3 weeks apart. Secondary end points were a decrease of > or = 50% in use of analgesic medication without an increase in pain, duration of response, and survival. Health-related quality of life was evaluated with a series of linear analog self-assessment scales (LASA and the Prostate Cancer-Specific Quality-of-Life Instrument [PROSQOLI]), the core questionnaire of the European Organization for Research and Treatment of Cancer (EORTC), and a disease-specific module.

RESULTS

Palliative response was observed in 23 of 80 patients (29%; 95% confidence interval, 19% to 40%) who received mitoxantrone plus prednisone, and in 10 of 81 patients (12%; 95% confidence interval, 6% to 22%) who received prednisone alone (P = .01). An additional seven patients in each group reduced analgesic medication > or = 50% without an increase in pain. The duration of palliation was longer in patients who received chemotherapy (median, 43 and 18 weeks; P < .0001, log-rank). Eleven of 50 patients randomized to prednisone treatment responded after addition of mitoxantrone. There was no difference in overall survival. Treatment was well tolerated, except for five episodes of possible cardiac toxicity in 130 patients who received mitoxantrone. Most responding patients had an improvement in quality-of-life scales and a decrease in serum prostate-specific antigen (PSA) level.

CONCLUSION

Chemotherapy with mitoxantrone and prednisone provides palliation for some patients with symptomatic hormone-resistant prostate cancer.

A model for the kinetic mechanism of sodium-coupled L-alanine transport in LLC-PK1 cells

The kinetics of sodium-dependent L-alanine transport were characterized in ATP-depleted LLC-PK1 cells, which allows experimental imposition of an interior negative diffusion potential across the plasma membrane. Under these conditions a wide range of sodium concentrations can be studied without altering the membrane potential. When Na+ is the variable substrate, the apparent maximal velocity (V max) for transport changes nearly fourfold for the five different alanine concentrations studied (0.05-2.0 mM). In contrast, at five different sodium concentrations, ranging from 10 to 135 mM, the apparent V max with variable alanine remains nearly constant at 5.3 +/- 1.2 nmol.min-1.mg cell protein-1. The ratio of the two primary kinetic parameters, Michaelis constant (Km)/V max, varies markedly no matter which solute is treated as the variable illustrate. These data are consistent with a simultaneous ordered transport mechanism in which sodium binds before alanine to the transport protein at the extracellular surface of the membrane. Alanine-dependent 22Na+ influx is more than five times faster if unlabeled intracellular sodium is present than in its absence. Sodium-dependent influx of [14C]alanine is more rapid than net alanine flux only if unlabeled Na+ and alanine are both present intracellularly. These results indicate that the cotransporter can function more rapidly in an exchange mode than when it catalyzes net solute uptake and that Na+ is the first solute to be released at the intracellular side of the membrane. A model is presented that can be used for further quantitative analysis of the kinetic and functional properties of the cotransport system.

Effects of cognitive coping skills training on coping strategies and experimental pain sensitivity in African American adults with sickle cell disease

The present study examined whether training in cognitive coping skills would enhance pain coping strategies and alter pain perception in adults with sickle cell disease (SCD). Sixty-four African Americans with SCD were randomly assigned to either a cognitive coping skills condition (three 45-min sessions in which patients were trained to use 6 cognitive coping strategies) or a disease-education control condition (three 45-min didactic-discussion sessions about SCD). Pain sensitivity to calibrated noxious stimulation was measured at pre- and posttesting, as were cognitive coping strategies, clinical pain, and health behaviors. Results indicated that, compared with the randomly assigned control condition, brief training in cognitive coping skills resulted in increased coping attempts, decreased negative thinking, and lower tendency to report pain during laboratory-induced noxious stimulation.

Characterization of simple and complex hepatitis C virus quasispecies by heteroduplex gel shift analysis: correlation with nucleotide sequencing

In infected humans, hepatitis C virus (HCV) exists as a quasispecies typically characterized by multiple nucleotide substitutions within the second envelope gene hypervariable region 1 (HVR1). In the current study, we used heteroduplex gel shift analysis (GSA) of HVR1 sequences amplified directly from patients' sera to define two patterns of HCV quasispecies: (i) simple quasispecies, which gave a mostly homogeneous gel shift profile with a single predominant band and (ii) complex quasispecies, which gave a gel shift profile with multiple bands. Recombinant HVR1 libraries were generated from two patients with complex HCV quasispecies (cases 1 and 2) and two patients with simple HCV quasispecies (cases 3 and 4), and 129 individual clones were analysed by either GSA, nucleotide sequencing or both techniques. In case 1 we identified a highly complex HCV quasispecies with 11 distinct HVR1 variants differing by 1-51 nucleotide changes. We found a general but not absolute correlation between GSA pattern and the number or position of nucleotide changes within HVR1. In case 2, the complex HCV quasispecies consisted of three distinct major variants; GSA of individual HVR1 clones allowed us to reconstruct the complex quasispecies pattern in vitro. In case 3, the simple quasispecies comprised 66% homogeneous clones and 33% unique minor variants differing by 1-3 nucleotides from the consensus sequence. In case 4, the simple quasispecies was 84% homogeneous, but six unique major shift variants were identified among 31 clones by GSA. In summary, HCV quasispecies can be characterized based on GSA profiles following direct PCR amplification of HVR1 sequences from patients' serum; the GSA profiles approximate the clonal population of HCV as determined by clonal analysis. GSA of HVR1 clones showed a strong correlation with nucleotide sequencing.

Bovine fast-twitch myosin light chain 1: cloning and mRNA amount in muscle of cattle treated with clenbuterol

The cDNA clone encoding the fast-twitch isoform of myosin light chain 1 (MLC-1f) was isolated from bovine longissimus dorsi muscle and sequenced in M13 and pUC8. An 0.8-kb subclone, produced by digestion of the cDNA with EcoRI, contained the portion of the molecule common to MLC-1f and MLC-3f. The cDNA in pUC8 contained an additional 81 bp upstream of the EcoR I digestion site, which was unique to MLC-1f. The cDNA clone was used to measure MLC-1f mRNA in longissimus dorsi muscle of cattle chronically administered the beta-adrenergic agonist clenbuterol. Treatment with clenbuterol for 50 days increased succinic dehydrogenase negative (type IIB) and positive (types I and IIA) myofiber cross-sectional areas by 25%. After the 50-day treatment period, the amount of MLC-1f mRNA was 90% greater in longissimus dorsi muscle of treated animals than in the initial group. This effect was lost when clenbuterol treatment was withdrawn for a 78-day period, during which time muscle growth in the treated animals stopped completely. We conclude that we have cloned the bovine cDNA for MLC-1f, which has provided additional evidence that beta-adrenergic agonists increase myofibrillar gene expression.

Lipogenic activity of intramuscular and subcutaneous adipose tissues from steers produced by different generations of angus sires

Simmental and Hereford cows (n = 74) were inseminated with semen from purebred Angus bulls from the 1960s or with semen from purebred Angus bulls from the 1980s. The F1 calves provided the foundation for two investigations, one addressing growth and carcass characteristics, and another measuring the impact of sire generation on lipid metabolism and adiposity. Calves sired by the 1980s-type bulls had greater (P < .05) birth, weaning, and final live weights and carcass weights. They also had larger (P < .05) hip heights and hip widths at weaning and larger (P < .05) hip heights and lower (P < .05) body condition scores at slaughter. There were no differences (P > .05) in any measure of fatness between groups (adjusted fat thickness, kidney, pelvic, and heart fat, or marbling scores), but yield grade was higher numerically (P < .1) for the 1980s steers. The second aspect of this research addressed the influence of different generations of Angus sires on specific carcass traits and adipose tissue metabolism. A subset of six steers for each generation type (from Simmental cows) were selected and samples were collected at slaughter for measurements in vitro. For both generation types, intramuscular (i.m.) adipocytes had lesser (P < .05) cell volumes than subcutaneous (s.c.) adipose tissue. Correspondingly. i.m. adipose tissue exhibited lower (P < .05) rates of 14C-labeled acetate incorporation into lipids as measured immediately after slaughter. Intramuscular and s.c. adipocytes from 1980s-type steers were smaller (P < .05) than those from the 1960s-types steers, with correspondingly more cells per gram of tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of ocean wave spectra from images of backscattered incoherent light

The application of imaging of sea surfaces has been investigated with respect to determination of sea wave spectra. Incoherent light is projected toward the sea surface, and the backscattered light is imaged with a camera. The primary scattering mechanism is assumed to be from particles suspended in the sea, so the backscattered intensity is determined primarily by the Fresnel coefficients. The ratio of the images detected at two orthogonal polarizations contains the desired information on the local slope of the sea surface, pixel by pixel, in one dimension. By integration, one can obtain the surface-height profile.

Transmission of the hepatitis-C virus by tissue transplantation

The hepatitis-C virus has been the most prevalent cause of chronic hepatitis in both blood and organ recipients. The introduction of a second-generation immunoassay for antibodies to the hepatitis-C virus (HCV 2.0) provided the opportunity to determine if the hepatitis-C virus can be transmitted through tissue transplantation. Banked sera from tissue donors that had previously been found to be non-reactive to the first-generation hepatitis-C virus antibody assay (HCV 1.0) and non-reactive for antibodies to hepatitis-B core antigen were retested with HCV 2.0. The sera from two donors were reactive; the transplant records of recipients of tissues from these donors were reviewed, and the surgeons or hospitals were contacted. The tissue recipients were tested with HCV 2.0, and positive sera were tested for hepatitis-C virus RNA by polymerase chain reaction. Viral nucleic acids isolated from viremic donors and recipients were analyzed for identity by sequencing of the hepatitis-C virus envelope gene (E2) hypervariable region. There were twenty-one grafts, which had been treated with gamma radiation, from one donor; thirteen had been transplanted to twelve recipients. Serum samples from six of the recipients were tested; one was reactive. This patient had other risk factors for infection with the hepatitis-C virus, and sequence analysis demonstrated non-identity between the donor and recipient hepatitis-C virus isolates. Nine of twelve grafts from a second donor had been transplanted in nine recipients. Serum samples from five patients were tested with HCV 2.0; four were reactive. In three of the four patients, the sera were determined to be positive for the hepatitis-C virus by polymerase chain reaction. E2 sequence analyses of hepatitis-C virus RNA isolates from two of these recipients demonstrated sequence identity with the donor isolate. The results of the present report demonstrate that the hepatitis-C virus can be transmitted by bone, ligament, and tendon allografts. They also support the need for testing of all tissue donors for antibodies to the hepatitis-C virus before the tissue is released for transplantation. The results also suggest that seventeen kilo-gray of gamma radiation may inactivate the hepatitis-C virus in tissue.

Evidence for preadipocyte proliferation during culture of subcutaneous and intramuscular adipose tissues from Angus and Wagyu crossbred steers

The primary objective of this study was to provide evidence for preadipocyte proliferation during culture of adipose tissue explants; a secondary objective was to compare the lipogenic activity and cellularity of adipose tissues from American Wagyu crossbred steers. Subcutaneous (s.c.) and intramuscular (i.m.) adipose tissues were obtained at slaughter from the 2nd to 6th lumbar region of the loin from Angus (n = 10) and Wagyu crossbred steers (n = 10) that had been fed for 552 d by typical Japanese production standards. Adipose tissue explants were incubated 36 h with [3H]thymidine in the absence and presence of aphidicolin (a specific inhibitor of genomic DNA replication). Adipocytes were liberated by collagenase treatment and [3H]thymidine incorporation into DNA was measured. Whereas there were no significant differences between adipose tissue depots, Wagyu s.c. and i.m. preadipocytes and stromal-vascular cells exhibited greater (P < .05) [3H]thymidine incorporation into DNA than adipocytes from Angus steers. Intramuscular adipose tissue from both breeds exhibited lower (P < .05) rates of lipogenesis from acetate both before and after long-term (36-h) incubation than s.c. adipose tissue. Furthermore, i.m. adipocytes were smaller (P < .05) than s.c. adipocytes. The activities of fatty acid synthetase and glucose-6-phosphate dehydrogenase were greater (P < .05) in Wagyu s.c. adipose tissue and less in Wagyu i.m. adipose tissue than in corresponding Angus tissues. There were no differences between breed types (P = .17) in rates of lipogenesis from acetate, either before or after explant culture.(ABSTRACT TRUNCATED AT 250 WORDS)

Remote sensing of wind velocity and strength of refractive turbulence using a two-spatial-filter receiver

Wind velocity across an optical path and refractive turbulence strength can be measured by observing a light source through the atmosphere with a receiver that contains two spatial filters. The frequency of the detected signal gives the transverse velocity of the turbulent structure, whereas signal intensity is proportional to refractive turbulence strength. The size of turbulent eddies that produce signals is determined by the optical setup. The position along the detector's field of view at which the measurement is made depends on the separation of the filters, and profiles can be made by varying the separation and using a telescope. The system requires longer integration times than one which uses a spatial filter at each end of the optical path, but it has the advantage of being able to use a natural source such as the Sun or a planet. An analysis of the system is presented along with numerical simulations and results from a short-range (several meters) laboratory experiment. The analysis assumes a single layer of refractive turbulence. Scales of the refractive turbulence in the inertial subrange from 5 to 20 cm will be of primary interest for this method.

Enhanced backscatter of a reflected beam in atmospheric turbulence

We measure the mean and the variance of the irradiance of a diverging laser beam after reflection from a retroreflector and from a plane mirror in a turbulent atmosphere. Increases in both the mean irradiance and the normalized variance are observed in the direct backscatter direction because of correlation of turbulence on the outgoing path and the return path. The backscattered irradiance is enhanced by a factor of ~ 2 and the variance by somewhat less.

Detection of hepatitis C virus RNA: comparison of one-stage polymerase chain reaction (PCR) with nested-set PCR

We evaluated a new hepatitis C virus RNA assay based on one-stage PCR followed by liquid hybridization with an oligonucleotide probe and compared it with nested-set PCR. The one-stage and nested-set PCR assays had identical sensitivities in analytical experiments and showed 100% concordance when clinical specimens were used. One-stage PCR may be less prone to contamination than nested-set PCR.

Triacylglycerol biosynthesis in bovine liver and subcutaneous adipose tissue

1. Adipose tissue from Angus and Brahman steers incubated with [1-14C]palmitate in the absence and presence of glucose exhibited a greater rate of lipid production than liver (P < 0.05). 2. Homogenates of adipose tissue used in the glycerol-3-phosphate acyltransferase assay exhibited a greater glycerolipid specific activity (nmol lipid/mg protein/30 min) when compared to liver (P < 0.05). 3. The inverse was true for liver homogenates when calculated for tissue activity (nmol lipid/g tissue/30 min). 4. Lysophosphatidate was produced in greater (P < 0.05) amounts than all other glycerolipids in the glycerol-3-phosphate acyltransferase assay. 5. The activity of phosphatidate phosphohydrolase in liver homogenates displayed greater rates than their respective adipose tissue homogenates. 6. Diacylglycerol acyltransferase activity was greater in adipose tissue homogenates compared to liver homogenates.

Two-color correlation of atmospheric scintillation

We present the results of measurements of the correlation of scintillations of two colors of light made in the turbulent atmosphere. In strong path-integrated turbulence the correlation is below that predicted by the weak-turbulence theory. A phenomological theoretical approach is used to account for saturation effects. This simple theory provides a reasonable approximation to the correlation data. Thus, we conclude that saturation effects reduce the two-color correlation of atmospheric scintillation.

IVC thrombosis: successful treatment with low dose streptokinase

Thrombosis of the inferior vena cava (IVC) is an infrequent cause of thrombosis when large series of patients with deep vein thrombosis are examined. It may provide a diagnostic challenge in that lower extremity edema may be absent. The management has varied in published series with different authors recommending anticoagulant therapy (heparin or fibrinolytic therapy), surgical venous thrombectomy, or IVC interruption. We describe a case of IVC thrombosis presenting with pulmonary emboli, successfully treated with low-dose infusional Streptokinase.

Fluidized bed adsorption for whole broth extraction

Fluidized bed adsorption using a high-density synthetic resin has proven to be an invaluable technique for separating novel compounds from unfiltered fermentation broths during the very early stages of fermentation development, where product concentrations are typically in the parts per million range. Previous initial downstream processing strategies consisted of cell separation from whole broth or direct extraction with water-immiscible solvents, both of which resulted in lengthy time cycles, conflicts with existing operations requiring the use of high-cost centrifugal separators, and environmental/solvent recovery concerns. Laboratory and subsequent pilot plant process development work along with concomitant improvements in yield, quality, and time cycles are presented for one of several fluidized bed processes piloted in Merck's Natural Product Isolation facility.

Fibrinolytic therapy for idiopathic subclavian-axillary vein thrombosis

We report our results in eight consecutive patients with idiopathic subclavian-axillary vein thrombosis treated at a community hospital with systemic streptokinase therapy. Seven of the eight patients were treated within 1 week of symptoms. All seven patients had partial or total recanalization documented by venography. One patient developed rethrombosis that did not respond to therapy with tPA and had mild persisting symptoms of postphlebitic syndrome. None of the other patients had symptoms of postphlebitic syndrome on follow-up up to 5 years' duration.

Acute and long-term lipogenic response to insulin and clenbuterol in bovine intramuscular and subcutaneous adipose tissues

The present study was conducted to determine whether insulin and clenbuterol affected either short-term (2-h) incubations or long-term (48-h) tissue cultures of i.m. and s.c. adipose tissue explants. Samples were taken from control steers and steers fed 7 mg.head-1.d-1 clenbuterol for 50 d, after which time the drug was withdrawn from the diet for 90 d prior to slaughter. Neither short-term incubations nor long-term explant cultures contained bovine serum albumin (BSA). Insulin (6.67 x 10(-9) M) had no effect (P greater than .05) on lipogenesis in s.c. and i.m. adipose tissue in 2-h tissue incubations of fresh adipose tissue. There was a substantial decrease in activity during the culture period, which was ameliorated somewhat in s.c. adipose tissue by the presence of insulin in the culture media. Clenbuterol exposure for 48 h in vitro decreased the production of lipids from acetate in both adipose tissue depots but had no effect in short-term adipose tissue incubations. Results from the present study confirm that omitting BSA from incubation media does not enhance the responsiveness of bovine s.c. adipose tissue or the less mature i.m. adipose tissue to insulin. Insulin may maintain greater cell viability in 48-h explant cultures.

Association of embolic stroke in pregnancy with the lupus anticoagulant. A case report

Recently the association of recurrent spontaneous abortions and intrauterine fetal death was linked to the lupus anticoagulant (LA). LA is an immunoglobulin directed against phospholipid, causing characteristic changes in coagulation tests, and is associated with an increased risk of thrombosis. We treated a pregnant woman who presented with an embolic stroke and laboratory evidence of LA.

Association of subclavian-axillary vein thrombosis with brachial neuritis

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