Na+ mechanism of delta-opioid receptor induced protection from anoxic K+ leakage in the cortex

Activation of delta-opioid receptors (DOR) attenuates anoxic K(+) leakage and protects cortical neurons from anoxic insults by inhibiting Na(+) influx. It is unknown, however, which pathway(s) that mediates the Na(+) influx is the target of DOR signal. In the present work, we found that, in the cortex, (1) DOR protection was largely dependent on the inhibition of anoxic Na(+) influxes mediated by voltage-gated Na(+) channels; (2) DOR activation inhibited Na(+) influx mediated by ionotropic glutamate N-methyl-D-aspartate (NMDA) receptors, but not that by non-NMDA receptors, although both played a role in anoxic K(+) derangement; and (3) DOR activation had little effect on Na(+)/Ca(2+) exchanger-based response to anoxia. We conclude that DOR activation attenuates anoxic K(+) derangement by restricting Na(+) influx mediated by Na(+) channels and NMDA receptors, and that non-NMDA receptors and Na(+)/Ca(2+) exchangers, although involved in anoxic K(+) derangement in certain degrees, are less likely the targets of DOR signal.

Phase II trial of sorafenib combined with dacarbazine in metastatic melanoma patients

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Background: Sorafenib inhibits tumor cell proliferation and angiogenesis through blockade of multiple kinases including Raf, VEGFR-2/-3, and PDGFR-β. In Phase I/II trials, sorafenib was generally well tolerated as a monotherapy or in combination with other agents. A Phase I study in combination with dacarbazine (DTIC) showed encouraging activity, which warranted this Phase II study. Methods: This multi-center, open-label, two-stage (30 patients in Stage 1; 52 in Stage 2), uncontrolled Phase II trial was performed to evaluate the primary endpoints of efficacy (according to RECIST) and tolerability of sorafenib in combination with DTIC in patients with advanced metastatic melanoma. Eligibility criteria included ECOG 0 or 1, life expectancy ≥12 weeks, adequate bone marrow, liver, and renal function. Oral sorafenib 400 mg twice daily (bid) was administered with repeated 3-week cycles of DTIC 1000 mg/m2. Results: At this interim end of Stage 1 analysis, 30 patients with metastatic melanoma had been treated (median age 61 years [range 30–78]; 73.3% male; 96.7% white). Five (16.7%) patients had PR as best response (two confirmed, three currently unconfirmed), 13 (43.3%) had SD, 10 (33.3%) had PD, and two (6.7%) were unevaluable for tumor response. The patients with confirmed PR continue on study drug at 6.4 months. Median progression-free survival for all patients was 3.6 months (range 0.9–6.1 months). The most frequently reported drug-related adverse events (AEs) were dermatologic (rash/desquamation [43%], hand-foot skin reaction [HFS, 33%]); gastrointestinal (constipation [47%], nausea [37%], diarrhea [27%]); constitutional (fatigue [43%]); and blood/bone marrow (neutrophils [40%], platelets [30%]). The most common grade 3/4 drug-related AEs were blood/bone marrow (neutrophils [23%], platelets [17%]), and fatigue (7%), while HFS and hypertension were observed in <5%. Conclusions: Continuous sorafenib 400 mg bid is generally well tolerated and shows promising preliminary anti-tumor activity in combination with DTIC. No toxicities were observed above those expected from either agent alone. Updated results will be presented, including the decision whether to proceed to Stage 2 of the study.

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The place of VEGF inhibition in the current management of renal cell carcinoma

Vascular endothelial growth factor (VEGF) is overexpressed in around 80% of patients with clear cell carcinoma of the kidney owing to the inactivation of von Hippel Lindau gene activity. VEGF stimulates angiogenesis and acts as an autocrine growth factor. A number of different agents are now available which target VEGF and its signalling pathways. A significant body of evidence has accumulated demonstrating that antagonism of VEGF and its downstream pathways is clinically useful in a significant proportion of patients with metastatic clear cell carcinoma of the kidney. Enough data is now available to recommend that patients with metastatic clear cell carcinoma of the kidney should at some point during the course of their disease be offered entry into a clinical trial enabling exposure to a targeted inhibitor of VEGF or its signalling pathways. Assuming early clinical trial data is substantiated by ongoing registration studies, efforts should be made to minimise the time taken between licensing and general availability of these active agents.

Paraneoplastic "stiff person syndrome" with metastatic adenocarcinoma and anti-Ri antibodies

A 43-year-old woman presented with clinical and electrophysiologic features of stiff person syndrome (SPS), without abdominal or lumbar paraspinal muscle involvement. Investigations revealed metastatic adenocarcinoma of the lung with positive anti-Ri antibodies. Her clinical condition improved with diazepam, baclofen, tizanidine, and palliative chemotherapy. Screening for an underlying malignancy and anti-Ri antibodies should be considered in patients with SPS when clinical presentation is atypical.

Dynamics of single and multiple bubbles and associated heat transfer in nucleate boiling under low gravity conditions

Experimental studies and numerical simulation of growth and lift-off processes of single bubbles formed on designed nucleation sites have been conducted under low-gravity conditions. Merging of multiple bubbles and lift-off processes during boiling of water in the parabola flights of KC-135 aircraft were also experimentally studied. The heating area of the flat heater surface was discretized and equipped with a number of small heating elements that were separately powered in the temperature-control mode. As such, the wall superheat remained nearly constant during the growth and departure of the bubbles, whereas the local heat flux varied during the boiling process. From numerical calculation it is found that peak of heat flux occurs locally at the contact line of bubble and heater surface. Dry conditions exist inside the bubble base area, which is characterized through a zero heat flux region in the numerical calculation and a lower heat flux period in the experimental results. During the merger of multiple bubbles, dry-out continues. In both the numerical calculations and experimental results, the bubble lift-off is associated with an apparent increase in heat flux. Wall heat flux variation with time and spatial distribution during the growth of a single bubble from numerical simulations are compared with experimental data.

The health-related quality of life and survival of small-cell lung cancer patients: results of a companion study to CALGB 9033

The purposes of this study were 2-fold: to evaluate the impact of the schedule dependency of etoposide (3-day IV short course vs. a 21-day oral prolonged course) with cisplatin on the quality of life of small-cell lung cancer (SCLC) patients; and to examine the effect of baseline quality of life variables on long-term survival, after adjustment for known demographic and clinical prognostic factors. Participants were 70 patients enrolled in the cancer and leukemia group B (CALGB) protocol 9033. Quality of life was assessed at baseline, 6 and 12 weeks by: the EORTC QLQ-30, the Centers for epidemiology studies--Depression short form, the medical outcomes study (MOS) social support questionnaire, and a scale of sleep quality. Contrary to expectations, study results suggested no significant differences in the patients' life quality and treatment response based on whether they received etoposide in a 3-day IV vs. a 21-day oral regimen. The use of the baseline variables in predicting overall survival indicated that patients who were non-white and with liver involvement had decreased survival. Brain involvement, being male, and higher depressive symptoms were also found to be borderline significant in predicting decreased survival in this patient population.

Helicobacter pylori: an update and a practical approach

Infections with Helicobacter pylori are very common throughout the world, occurring in 40% to 50% of the population in developed countries and in 80% to 90% of the population in developing regions. Helicobacter pylori is now recognized as a major cause of gastritis and peptic ulcer disease; it has been implicated as a cause of gastric mucosa-associated lymphoid-tissue lymphomas, and it increases the risk of gastric adenocarcinoma in chronic carriers. Eradication of Helicobacter pylori has been shown to decrease ulcer recurrence and, in some cases, is associated with regression of the gastric mucosa-associated lymphoid-tissue lymphoma. Helicobacter pylori infection has been classified as a category 1 carcinogen by the World Health Organization. Treatment should be offered if the infection is detected. It is important for primary care physicians to clearly understand when and how to test and how to select appropriate therapy for Helicobacter pylori infection.

Reevaluation of the 1997 TNM classification for renal cell carcinoma: T1 and T2 cutoff point at 4.5 rather than 7 cm. better correlates with clinical outcome

PURPOSE

We analyzed the effects of the change in TNM classification from the 1987 to the 1997 version and suggest a modified tumor size cutoff point between T stages 1 and 2 for renal cell carcinoma.

MATERIALS AND METHODS

We evaluated a database containing the records of 661 patients who underwent nephrectomy between 1989 and 1999. The effect of the change in TNM classification on the distribution of patients between stages, the rates of M+ and N+ disease, and the local and distant recurrence rates were outlined for 280 patients with T stages 1 and 2 disease. The Cox model was used to identify the optimal cutoff point between T1 and T2 disease, and the resulting effect of adopting this cutoff was outlined.

RESULTS

A total of 174 and 128 cases were down staged from 1987 version stage T2 to 1997 version stage T1 and from 1987 TNM stage II to 1997 TNM stage I, respectively. Survival was not significantly different in patients with 1997 TNM stages I and II disease due to a lack of survival difference during the first 2 years of followup. Stage shift also caused an increase in average tumor size, the proportion of patients with high grade cancer, and M+ and N+ disease at diagnosis in 1997 stages T1 and T2 as well as an increase in the proportion of 1997 stage T2N0M0 cases at diagnosis with systemic failure. Analysis of 11 potential cutoff points between 1 and 10 cm. revealed that 4.5 cm. was most predictive of patients survival (hazards ratio 4.99, p = 0.0001). Using this cutoff resulted in improved discriminatory power of the TNM classification and a moderating effect on the distribution of patients, average tumor size, high grade disease, M+ and N+ disease at diagnosis, and systemic failure between T(14.5) and T(24.5) compared with 1997 T1 and T2.

CONCLUSIONS

Our data imply that the current cutoff point of 7 cm. between stages T1 and T2 tumors is too high. Lowering the cutoff to 4.5 cm. resulted in better discriminatory power of the TNM classification in our dataset. This observation should be further validated by external data.

Lifestyle interventions influence relative errors in self-reported diet intake of sodium and potassium

PURPOSE

To characterize the distribution of errors in self-reported sodium and potassium dietary intakes relative to more objective urine measures among participants receiving lifestyle interventions.

METHODS

We analyzed longitudinal data from 900 individuals with hypertension who had been enrolled in a randomized controlled clinical trial to establish whether usual care or three lifestyle interventions (weight loss, sodium reduction, and combined weight loss and sodium reduction) could effectively substitute for phamacotherapy. Repeated standardized 24-hour diet recalls and 24-hour urine collections were collected over up to three years of follow-up to estimate sodium and potassium intakes. By contrasting self-reported and urine-based sodium and potassium data collected before and during interventions, we examined the relative impact of intervention assignment on estimated intakes, repeatability, and multivariate measurement error.

RESULTS

Relative to urine-based measures, mean self-reported sodium intakes were biased about 10% lower among participants assigned to combined weight loss and sodium reduction, but were unaffected by the other interventions. The repeatability of self-report measures increased slightly with time, particularly among participants assigned to sodium interventions. Errors in self-reported sodium and potassium intakes were correlated before the start of the intervention, but became uncorrelated among individuals assigned to sodium restriction interventions.

CONCLUSIONS

Lifestyle interventions may influence not only diet intake, but also the measurement of diet intake.

Bladder cancer 2000: molecular markers for the diagnosis of transitional cell carcinoma

The search continues for better tumor markers to improve the rate of detection of transitional cell carcinoma (TCC) more quickly in larger populations and to predict the possibility of disease recurrence. Among several new tests currently being screened, telomerase and hyaluronic acid/hyaluronidase (HA/HAase) have shown sensitivity and specificity equal to or better than cytology, and other promising tumor markers are being investigated. Although no marker has yet replaced the need to perform cystoscopy and cytology, the new tests can minimize the cost and difficulty of screening and long-term surveillance of patients who have or are at risk for bladder cancer.

Color and duplex Doppler sonography of hemangiopericytoma

We report the color Doppler sonographic features in a case of hemangiopericytoma of the thigh in a 52-year-old woman. Color Doppler sonography demonstrated the vascularity of the tumor, and spectral analysis showed waveform changes that suggested the presence of intratumoral arteriovenous shunting. The color Doppler findings correlated well with angiographic findings. Color Doppler sonography can demonstrate intratumoral arteriovenous shunting in hemangiopericytoma and may be used to help avoid profuse bleeding when performing a preoperative biopsy.

A shift in the phenotype of melan-A-specific CTL identifies melanoma patients with an active tumor-specific immune response

In a significant proportion of melanoma patients, CTL specific for the melan-A(26/7-35) epitope can be detected in peripheral blood using HLA-A2/peptide tetramers. However, the functional capacity of these CTL has been controversial, since although they prove to be effective killers after in vitro expansion, in some patients they have blunted activation responses ex vivo. We used phenotypic markers to characterize melan-A tetramer(+) cells in both normal individuals and melanoma patients, and correlated these markers with ex vivo assays of CTL function. Melanoma patients with detectable melan-A tetramer(+) cells in peripheral blood fell into two groups. Seven of thirteen patients had a CCR7(+) CD45R0(-) CD45RA(+) phenotype, the same as that found in some healthy controls, and this phenotype was associated with a lack of response to melan-A peptide ex vivo. In the remaining six patients, melan-A tetramer(+) cells were shifted toward a CCR7(-) CD45R0(+) CD45RA(-) phenotype, and responses to melan-A peptide could be readily demonstrated ex vivo. When lymph nodes infiltrated by melan-A-expressing melanoma cells were examined, a similar dichotomy emerged. These findings demonstrate that activation of melan-A-specific CTL occurs in only some patients with malignant melanoma, and that only patients with such active immune responses are capable of responding to Ag in ex vivo assays.

Exercise adherence among older adults: challenges and strategies

This paper explores physical activity adherence among older adults in clinical research. We address the unique challenges associated with promoting physical activity, including the amount of time and effort, perceived benefits, and recommendations from professionals. We explore useful strategies to enhance adherence in the realm of physical activity interventions, including the development of theory-based physical activity interventions that acknowledge participant needs and expectations, promote self-regulatory skills, view exercise as an ongoing process subject to relapse, and utilize phone contacts for home-based activity programs. We conclude with directions for future clinical trials to enhance exercise adherence that include the need for a precise definition and operationalization of adherence, linkages between physical activity interventions and theory, and the study of exercise in both structured and home-based settings. Control Clin Trials 2000;21:212S-217S

Effect of voluntary weight loss on bone mineral density in older overweight women

OBJECTIVES

To examine the effect of diet and exercise-induced weight loss on bone mineral density in overweight postmenopausal women

DESIGN

A 1-year prospective, randomized clinical trial.

SETTING

Two university medical school research centers.

PARTICIPANTS

Sixty-seven overweight postmenopausal women, a subset of the women who participated in the Trial of Nonpharmacological Interventions in the Elderly (TONE) to control hypertension. The participants were assigned randomly to one of four groups: usual care, weight loss only, sodium restriction only, or combined weight loss/sodium restriction.

INTERVENTION

All TONE participants in the treatment groups attended regular dietary intervention sessions to lose weight, reduce sodium intake, or both that they might refrain from using antihypertensive medications for a period of 15 to 36 months (median = 29 months).

MEASUREMENTS

Bone mineral density (BMD) assessed by dual energy X-ray absorptiometry (DXA), serum and urine markers of bone metabolism, and other demographic and clinical data were collected at baseline, 6 months, and 12 months.

RESULTS

Women assigned to the weight loss interventions lost 9.2 +/- 1.2 lbs (mean +/- SE) at 6 months and 7.7 +/- 2.0 lbs at 12 months compared with 1.8 +/- 1.0 lbs at 6 months and 1.9 +/- 1.6 lbs at 12 months for those assigned to no weight loss intervention (P < .0001). Weight loss was correlated with a decrease in total body BMD (P = .004) and an increase in osteocalcin (P = .004) after controlling for baseline bone measures, intervention assignment, and other baseline covariates. Regression analyses indicated that total body BMD decreased by 6.25 +/- 2.06 g/cm2 x 10-4 for each pound of weight loss.

CONCLUSIONS

Voluntary weight loss in overweight postmenopausal women is associated with modest decrease in total body BMD. Clinicians recommending weight loss for older postmenopausal women may need to include recommendations for reducing the risk of bone loss.

The effects of DNA containing CpG motif on dendritic cells

Dendritic cells (DC) are specialized antigen-presenting cells. DC can acquire and process antigens in the periphery before maturing and migrating to secondary lymphoid tissues where they present the antigens and deliver co-stimulatory signals to T cells. We describe an immunostimulatory oligonucleotide containing a CpG motif that stimulated murine DC to up-regulate co-stimulatory molecules, induce T-cell proliferative responses and secrete interleukin-12 in vitro. Administration of this oligonucleotide, but not of a control oligonucleotide lacking this motif, to mice led to the disappearance of DC from the marginal zone and T-cell areas of spleen, but not from heart or kidney. The same CpG did not cause maturation of monocyte-derived human DC in vitro, but lipopolysaccharide-treated monocyte-derived DC showed enhanced functional activity and up-regulated co-stimulatory molecules.