Artificial intelligence-enhanced electrocardiogram analysis for identifying cardiac autonomic neuropathy in patients with diabetes

AIM

To develop and employ machine learning (ML) algorithms to analyse electrocardiograms (ECGs) for the diagnosis of cardiac autonomic neuropathy (CAN).

MATERIALS AND METHODS

We used motif and discord extraction techniques, alongside long short-term memory networks, to analyse 12-lead, 10-s ECG tracings to detect CAN in patients with diabetes. The performance of these methods with the support vector machine classification model was evaluated using 10-fold cross validation with the following metrics: accuracy, precision, recall, F1 score, and area under the receiver-operating characteristic curve (AUC).

RESULTS

Among 205 patients (mean age 54 ± 17 years, 54% female), 100 were diagnosed with CAN, including 38 with definite or severe CAN (dsCAN) and 62 with early CAN (eCAN). The best model performance for dsCAN classification was achieved using both motifs and discords, with an accuracy of 0.92, an F1 score of 0.92, a recall at 0.94, a precision of 0.91, and an excellent AUC of 0.93 (95% confidence interval [CI] 0.91-0.94). For the detection of any stage of CAN, the approach combining motifs and discords yielded the best results, with an accuracy of 0.65, F1 score of 0.68, a recall of 0.75, a precision of 0.68, and an AUC of 0.68 (95% CI 0.54-0.81).

CONCLUSION

Our study highlights the potential of using ML techniques, particularly motifs and discords, to effectively detect dsCAN in patients with diabetes. This approach could be applied in large-scale screening of CAN, particularly to identify definite/severe CAN where cardiovascular risk factor modification may be initiated.

Serum Markers of Bone Turnover Following Controlled Administration of Two Medical Cannabis Products in Healthy Adults

Introduction: Cannabidiol (CBD) has been shown to maintain bone integrity in pre-clinical models, but little is known about the effects of delta-9-tetrahydrocannabinol (THC) on bone turnover. In this study we explored the effects of two oral medical cannabis products on normal bone homeostasis through evaluation of markers of bone resorption (carboxyl-terminal collagen crosslinks, CTx) and bone formation (procollagen type 1 N-terminal propeptide, P1NP; alkaline phosphatase, ALP). Methods: This study is an analysis of secondary data from two Phase 1 double-blind, placebo-controlled trials of Spectrum Yellow (0.9 mg THC, 20 mg CBD/mL of oil) and Spectrum Red (2.5 mg THC, 0.3 mg CBD/softgel). Healthy participants (n=38 men, 45 women) were randomized to receive 5-20 mg THC (CBD levels varied as a function of administered product) or placebo daily (BID) for 7 days. Bone markers were assessed at baseline, upon completion of product administration (day 8), and after a 5-day washout (day 13). Results: All bone markers were significantly higher in men at baseline (p≤0.008). For CTx, there was a significant day×group interaction (F=3.23, p=0.04); CTx levels were significantly lower in participants treated with Spectrum Red (b=-164.28; 95% confidence interval [CI], -328 to -0.29; p=0.04) and marginally lower in participants treated with Spectrum Yellow (b=-157.31; 95% CI, -323 to 8.68; p=0.06) versus placebo on day 8. For P1NP and ALP, there were no significant differences between treatments across study days. Bone marker values outside the reference range (RR) were observed; CTx > RR (n=71) was predominantly (85.9%) observed in male participants, whereas P1NP > RR (n=100) was more evenly distributed between sexes (53.0% in men). These were not considered clinically significant and did not differ between treatment groups. Conclusions: These are the first interventional human data on the effect of cannabinoids on biomarkers of bone turnover. Short-term treatment with CBD- or THC-dominant medical cannabis products resulted in attenuation of a marker of bone resorption. Although the attenuation was not clinically significant, this finding may be indicative of protective properties of cannabinoids in bone. Further research over longer dosing durations in individuals exhibiting bone-specific conditions (e.g., osteoporosis) is warranted. ClinicalTrials.gov IDs: ACTRN12619001723178 and ACTRN12619001450101.

Pharmacokinetics of Oral Minor Cannabinoids in Blood and Brain

Introduction: Minor cannabinoids are increasingly being consumed in oral formulations (i.e., edibles, tinctures) for medical and nonmedical purposes. This study examined the pharmacokinetics (PKs) of cannabinoids tetrahydrocannabivarin (THCV), cannabichromene (CBC), cannabinol (CBN), and delta-8-tetrahydrocannabinol (D8-THC) after the first and last oral dose during a 14-day administration period. Materials and Methods: Sprague-Dawley rats (N=6 animals/dose, 50% female) were given an assigned dose of one of four cannabinoids (THCV=3.2-100 mg/kg, CBC=3.2-100 mg/kg, CBN=1-100 mg/kg, or D8-THC=0.32-10 mg/kg) or vehicle (medium-chain triglyceride oil) through oral gavage once daily for 14 days. Blood was collected 45 min and 1.5, 3, and 24 h following the first dose (day 1) and the last dose (day 14) of repeated oral cannabinoid treatment for PK analysis. Outcomes of interest included time to maximum concentration (Tmax), maximum concentration (Cmax), and area under the concentration versus time curve (AUClast). Dose-normalized (DN) Cmax and DN AUClast were also calculated. Brain tissue was collected 24 h post-administration of the first (day 1) and the last (day 14) dose of each cannabinoid to determine concentrations in brain. Results: All cannabinoids tested were detectable in plasma after single and 14-day repeated dosing. DN Cmax and DN AUClast were highest for D8-THC, followed by CBC, CBN, and THCV. There was no sex difference observed in cannabinoid kinetics. Accumulation of D8-THC in plasma was observed after 14 days of administration. THCV levels in plasma were lower on day 14 compared to day 1, indicating potential adaptation of metabolic pathways and increased drug elimination. Cannabinoids were detected in brain tissue 24 h post-administration of the first and the last dose of 17-100 mg/kg THCV, 3.2-100 mg/kg CBC, 10-100 mg/kg CBN, and 10 mg/kg D8-THC. Conclusions: THCV, CBC, CBN, and D8-THC produced detectable levels in plasma and translocated to brain tissue after the first dose (day 1) and the last dose (day 14) of repeated oral dosing. Examination of PKs of these minor cannabinoids in blood and brain provides a critical step for informing target dose ranges and dosing schedules in future studies that evaluate the potential effects of these compounds.

Toxicological Evaluation and Pain Assessment of Four Minor Cannabinoids Following 14-Day Oral Administration in Rats

Introduction: Despite growing consumer interest and market availability, the safety of minor cannabinoids, generally present in low concentrations in Cannabis sativa L., is not well understood. Materials and Methods: Cannabichromene (CBC; 3.2, 10, 17, 22, 32, or 100 mg/kg-bw/day), cannabinol (CBN; 1, 3.2, 10, 17, 32, or 100 mg/kg-bw/day), delta-8-tetrahydrocannabinol (D8-THC; 0.32, 1, 3.2, or 10 mg/kg-bw/day), tetrahydrocannabivarin (THCV; 3.2, 10, 17, 22, 32, or 100 mg/kg-bw/day), and vehicle (medium-chain triglyceride oil) preparations were administered via oral gavage once daily for 14 days to Sprague Dawley rats. Changes in behavior, body weight, food consumption, clinical pathology, organ weights, body temperature, and thermal pain sensitivity (tail flick assay) were assessed. Select organ tissues were collected at terminal necropsy and fixed for histopathological examination. Results: No treatment-related deaths were observed throughout the study, and cannabinoids were generally well tolerated. While some significant trends in body weight differences from controls (increases and decreases) were observed, these occurred independently of food consumption. Overall, differences in serum chemistry and hematology parameters between cannabinoid groups and their respective control groups were considered to occur due to biological variation among rats. No treatment-related gross abnormalities were observed in examined organs. Significant changes in absolute and relative organ weights occurred primarily in males and were generally of negligible magnitude. There were no biologically significant histopathological observations. While pain tolerance was significantly improved in animals treated with D8-THC (3.2 and 10 mg/kg-bw/day, day 14), results across minor cannabinoids were inconsistent and warrant further study. Conclusion: Minor cannabinoids were well tolerated across 14 days of daily oral administration at the doses assessed. Modest, dose-dependent trends in relative organ weights and serum chemistry parameters warrant exploration at higher oral doses. These data will assist in dose selection for future studies investigating the long-term safety and effects of CBC, CBN, D8-THC, and THCV.

Oral Cannabidiol Treatment in Two Postmenopausal Women with Osteopenia: A Case Series

Introduction: Cannabidiol (CBD), a nonintoxicating cannabinoid, may be involved in bone remodeling, but human studies are limited. In this case series, we explored the effects of oral CBD administration on bone turnover. Materials and Methods: Two postmenopausal women with osteopenia (T-score=-1 to -2.5) were randomized to receive 100 or 300 mg CBD daily (oral, bis in die [twice per day]) for 12 weeks. Serum markers of bone resorption (carboxyl-terminal collagen crosslinks [CTx]) and bone formation (procollagen type 1 N-terminal propeptide [P1NP], bone-specific alkaline phosphatase [BSAP], and osteocalcin [OC]); safety measures; plasma concentrations of CBD and metabolites; sleep disturbance; symptoms of depression, anxiety, and stress; and quality of life, were assessed. Results: CBD was well tolerated, with no clinically significant change in vital signs, hematology, chemistry, or urinalysis, and no adverse events reported. Reductions (% change vs. baseline) in CTx (-8.5%, -28.1%), P1NP (-9.9%, -39.5%), BSAP (-12.7%, -74.8%), and OC (-16.0%, -6.7%) were observed after 12 weeks of oral administration of 100 or 300 mg CBD daily, respectively. The two participants self-reported consuming 95.3% and 98.8% of CBD doses, respectively. CBD and select metabolites were measurable in plasma after 4 and 12 weeks of CBD treatment. No notable changes in sleep disturbance, depression, anxiety, stress, or quality of life were observed. Conclusions: CBD was well tolerated after 12 weeks of twice-daily oral administration and was associated with reduction in measured markers of bone turnover. Compliance with CBD treatment was good. Large-scale randomized clinical trials into the bone protective effects of CBD in postmenopausal women are warranted.

Machine learning profiles of cardiovascular risk in patients with diabetes mellitus: the Silesia Diabetes-Heart Project

AIMS

As cardiovascular disease (CVD) is a leading cause of death for patients with diabetes mellitus (DM), we aimed to find important factors that predict cardiovascular (CV) risk using a machine learning (ML) approach.

METHODS AND RESULTS

We performed a single center, observational study in a cohort of 238 DM patients (mean age ± SD 52.15 ± 17.27 years, 54% female) as a part of the Silesia Diabetes-Heart Project. Having gathered patients' medical history, demographic data, laboratory test results, results from the Michigan Neuropathy Screening Instrument (assessing diabetic peripheral neuropathy) and Ewing's battery examination (determining the presence of cardiovascular autonomic neuropathy), we managed use a ML approach to predict the occurrence of overt CVD on the basis of five most discriminative predictors with the area under the receiver operating characteristic curve of 0.86 (95% CI 0.80-0.91). Those features included the presence of past or current foot ulceration, age, the treatment with beta-blocker (BB) and angiotensin converting enzyme inhibitor (ACEi). On the basis of the aforementioned parameters, unsupervised clustering identified different CV risk groups. The highest CV risk was determined for the eldest patients treated in large extent with ACEi but not BB and having current foot ulceration, and for slightly younger individuals treated extensively with both above-mentioned drugs, with relatively small percentage of diabetic ulceration.

CONCLUSIONS

Using a ML approach in a prospective cohort of patients with DM, we identified important factors that predicted CV risk. If a patient was treated with ACEi or BB, is older and has/had a foot ulcer, this strongly predicts that he/she is at high risk of having overt CVD.

Sex Differences in the Pharmacokinetics of Cannabidiol and Metabolites Following Oral Administration of a Cannabidiol-Dominant Cannabis Oil in Healthy Adults

Introduction: Oral cannabidiol (CBD) product use is increasingly growing among women; however, there is a lack of data on sex differences in the pharmacokinetics (PKs) of CBD and its primary metabolites, 7-hydroxy-CBD (7-OH-CBD) and 7-carboxy-CBD (7-COOH-CBD), after repeated doses. Materials and Methods: The present study is a secondary analysis of data from a randomized, double-blind, placebo-controlled multiple-dose trial of a commercially available, CBD-dominant oral cannabis product. Healthy participants (n=17 males and 15 females) were randomized to receive 120 to 480 mg of CBD daily for 7 days. Dosing groups were pooled for all analyses due to sample size limitations. Analyses compared plasma PK parameters by sex, day, and sex×day. Results: For raw PK parameters for CBD and metabolites, there were no statistically significant effects of sex×day or sex (all p-values >0.05). For metabolite-to-parent ratios (MPRs) of AUC_0-t, there were significant effects of the sex×day interactions for 7-OH-CBD (F=6.89, p=0.016) and 7-COOH-CBD (F=5.96, p=0.021). For 7-OH-CBD, follow-up analyses showed significant simple effects of day within females (t=4.13, p<0.001), but not within males (t=0.34, p=0.73), such that 7-OH-CBD MPRs increased significantly from day 1 to 7 for females, but not for males. For 7-COOH-CBD, follow-up analyses revealed significant simple effects of day within females (t=8.24, p<0.001) and males (t=5.20, p<0.001), therefore 7-COOH-CBD MPRs increased significantly from day 1 to 7 in both sexes, but the increase was significantly greater among females than among males. Within dosing days, there were no statistically significant simple effects of sex on MPRs of 7-OH-CBD or 7-COOH-CBD. Conclusions: Females exhibited greater relative exposure to CBD metabolites in plasma over time, which may reflect sex differences in CBD metabolism or elimination. Further research assessing the safety implications of higher relative exposure to CBD metabolites over longer periods of time is warranted to mirror typical consumer use patterns.

Characterization of aerosols from hemp-derived pre-roll joints

OBJECTIVE

Availability and consumer use of hemp products is rapidly increasing, but little work has been done to assess aerosol emissions of hemp pre-rolls. The objective of this research was to characterize the aerosol of pre-rolled joints from hemp material enriched for production of cannabigerol (CBG) that were smoked on a test system mimicking human use patterns.

MATERIALS AND METHODS

Aerosol emissions were collected and analyzed using glass microfiber filters and charcoal cartridges. The aerosol was screened for nine phytocannabinoids and 19 terpenes.

RESULTS

Three phytocannabinoids (CBG, cannabichromene (CBC), and delta-9-tetrahydrocannabinol (THC)) were detected and quantified at a mean (SD) concentration of 19.4 (4.7), 0.48 (0.01), and 0.40 (0.04) mg per pre-roll, respectively. Five terpenes ((-)-α-bisabolol, (-)-guaiol, β-caryophyllene, nerolidol, and α-humulene) were detected and quantified at an average concentration of 352.7 (112.0), 194.3 (66.4), 106.0 (50.4), 28.3 (9.3), and 27.7 (11.2) µg per pre-roll, respectively. Particle size distribution testing via aerodynamic particle sizer and inertial impactor showed that average size of emitted aerosols was 0.77 (0.0) and 0.54 (0.1) µm, respectively.

CONCLUSIONS

This study describes methodology for characterization of cannabinoid and terpene dose in emitted aerosols and aerosolization efficiency from hemp pre-rolls. It also presents these data for one of the marketed products.

Diabetic peripheral neuropathy is associated with diabetic kidney disease and cardiovascular disease – The Silesia Diabetes-Heart Project

Microvascular complications of diabetes seem to be clustered and put patients at higher risk of developing cardiovascular disease (CVD). This was a questionnaire-based study designed to screen for the presence of diabetic peripheral neuropathy (DPN), defined as the score in the Michigan Neuropathy Screening Instrument (MNSI) above 2, and to evaluate its association with other complication of diabetes, including CVD. There were 184 patients included into the study. The prevalence of DPN in the study group was 37.5%. The regression model analysis revealed that the presence of DPN was significantly associated with the presence of diabetic kidney disease (DKD) (P = 0.0034;) and patient's age (P < 0.0001). Thirty-four patients (49.3%) with MNSI score >2 were diagnosed with CVD in comparison to 24 (20.1%) subjects with MNSI score ≤ 2 (P = 0.00006). In case of having one diabetes complication diagnosed, it is important to screen for others, including macrovascular ones.

Pharmacokinetics of Cannabidiol in Sprague-Dawley Rats After Oral and Pulmonary Administration

Introduction: Cannabidiol (CBD) is primarily consumed through ingestion and inhalation. Little is known about how CBD pharmacokinetics differ between routes of administration, and duration of pulmonary exposure. Methods: Pharmacokinetics, brain distribution, and urinary elimination of CBD and its major metabolites (6-hydroxy-cannabidiol [6-OH-CBD], 7-hydroxy-cannabidiol [7-OH-CBD], 7-carboxy-cannabidiol [7-COOH-CBD], and CBD-glucuronide) were evaluated in adult Sprague-Dawley rats following a single oral CBD ingestion (10 mg/kg in medium chain triglyceride oil; 24 male animals), and 1 or 14 days of repeated inhalation (0.9-13.9 mg/kg in propylene glycol [41%/59% by weight]; 5 male and 5 female animals per dose). Blood and brain tissue were collected at a single time point from each animal. Collection times were staggered from 5 min to 24 h postoral gavage or first (blood only) and final inhalation. Urine was collected 24 h postoral gavage or final inhalation. Samples were analyzed through liquid chromatography-mass spectrometry (LC-MS/MS). Results: CBD was more rapidly absorbed following inhalation than ingestion (T_max=5 min and 2 h, respectively). Inhalation resulted in a dose-responsive increase in CBD C_max and AUC_last. CBD C_max was 24-fold higher following the highest pulmonary dose (13.9 mg/kg) versus an oral dose of comparable concentration (10 mg/kg). C_max and AUC_last (0-16 h) trended higher following repeated exposure. Elimination was notably faster with repeated CBD inhalation (t_1/2=5.3 and 2.4 h on days 1 and 14, respectively). While metabolites were detectable in plasma, AUC_last (0-2 h) was at least 10- (7-OH-CBD, 7-COOH-CBD) to 100- (6-OH-CBD) fold lower than the parent compound. Metabolite concentration trended higher following repeated inhalation (6.7 mg/kg CBD); AUC_last (0-16 h) was ∼1.8-, ∼1.4-, and ∼2.4-fold higher following 14 days of exposure for 6-OH-CBD, 7-OH-CBD, and 7-COOH-CBD, respectively. CBD was detectable in brain homogenate tissue 24-h after 14-day inhalation (>3.5 mg/kg deposited dose) or a single oral administration. CBD metabolites were only measurable in brain tissue following the highest inhaled dose (13.9 mg/kg CBD). CBD, but not metabolites, was detectable in urine for all dose groups following 2 weeks of CBD inhalation. Neither CBD nor metabolites were present in urine after oral administration. Conclusion: CBD pharmacokinetics differ across oral and pulmonary routes of administration and acute or repeated dosing.

Preliminary Investigation of the Safety of Escalating Cannabinoid Doses in Healthy Dogs

Objective: To determine the safety and tolerability of escalating doses of three cannabis oil formulations, containing predominantly CBD, THC, or CBD and THC (1.5:1) vs. placebo in dogs. Design: Randomized, placebo-controlled, blinded, parallel study. Animals: Twenty healthy Beagle dogs (10 males, 10 females). Methods: Dogs were randomly assigned to one of five treatment groups (n = 4 dogs per group balanced by sex): CBD-predominant oil, THC-predominant oil, CBD/THC-predominant oil (1.5:1), sunflower oil placebo, medium-chain triglyceride oil placebo. Up to 10 escalating doses of the oils were planned for administration via oral gavage, with at least 3 days separating doses. Clinical observations, physical examinations, complete blood counts, clinical chemistry, and plasma cannabinoids were used to assess safety, tolerability, and the occurrence of adverse events (AEs). AEs were rated as mild, moderate, or severe/medically significant. Results: Dose escalation of the CBD-predominant oil formulation was shown to be as safe as placebo and safer than dose escalation of oils containing THC (CBD/THC oil or THC oil). The placebo oils were delivered up to 10 escalating volumes, the CBD oil up to the tenth dose (640.5 mg; ~62 mg/kg), the THC oil up to the tenth dose (597.6 mg; ~49 mg/kg), and the CBD/THC oil up to the fifth dose (140.8/96.6 mg CBD/THC; ~12 mg/kg CBD + 8 mg/kg THC). AEs were reported in all dogs across the five groups and the majority (94.9%) were mild. Moderate AEs (4.4% of all AEs) and severe/medically significant AEs (0.8% of all AEs) manifested as constitutional (lethargy, hypothermia) or neurological (ataxia) symptoms and mainly occurred across the two groups receiving oils containing THC (CBD/THC oil or THC oil). Conclusions and clinical significance: Overall, dogs tolerated dose escalation of the CBD oil well, experiencing only mild AEs. The favorable safety profile of 10 escalating doses of a CBD oil containing 18.3-640.5 mg CBD per dose (~2-62 mg/kg) provides comparative evidence that, at our investigated doses, a CBD-predominant oil formulation was safer and more tolerated in dogs than oil formulations containing higher concentrations of THC.

Breast cancer surgery decreases serum brain-derived neurotrophic factor concentrations in middle aged women: relationship to the serum C-reactive protein concentration

The aim of this study was to establish the effect of breast cancer surgery in middle aged women on the serum _(s) and plasma _(p) brain-derived neurotrophic factor concentrations [BDNF]_s and [BDNF]_p, respectively, in relation to the serum C-reactive protein [CRP]_s concentration measured before and at 24 hours after surgery. Eighteen patients with recently diagnosed breast cancer (mean ± SE): age 49.1 ± 1.6 years, body mass 69.8 ± 2.2 kg, BMI 25.8 ± 0.8 kg m^-2, participated in this study. The [BDNF]_s before the surgery amounted to 25 523 ± 1 416 pg ml^-1. At 24 h after the surgery it decreased to 21 551 ± 998 pg ml^-1 (P = 0.004). This decrease was accompanied by a significant (P = 0.001) decrease in the platelet count (PLT) from 254.7 ± 12.2 k μl^-1 before, to 228.8 ± 9.7 k μl^-1 after the surgery. The [CRP]_s increased from 3.59 ± 0.79 mg l^-1 before to 25.04 ± 4.65 mg l^-1 after the surgery (P = 0.002). A significant positive correlation was found between the [BDNF]_s and the PLT both before (P = 0.003) as well as after the surgery (P = 0.027). Moreover, a significant positive correlation (P = 0.046) was found between [BDNF]_s and the [CRP] _s before the surgery. At 24 h after the surgery the [BDNF]_s and the [CRP]_s still correlated positively (P = 0.044), despite the fact that the surgery significantlly decresed the [BDNF]_s and increased [CRP]_s. No significant effect of the surgery on the [BDNF]_p was found. We have concluded that serum BDNF concentration in breast cancer patients positively correlates with serum CRP both before and at 24 h after the surgery. Moreover, breast cancer surgery decreases serum BDNF concentration at 24 h after operation and increases [CRP]_s.

SUN-011 Identification Of Regulators Of Estrogenic Signalling In ER-positive Breast Cancer Cells By Whole Genome shRNA Screening

Over 70% of breast tumours express estrogen receptor alpha (ERα), a ligand-inducible transcription factor. Stimulation with estradiol leads to receptor binding to estrogen response elements (EREs) in target genes regulatory sequences in association with transcriptional cofactors. This results in altered gene expression, increased cell proliferation and accelerated tumour growth. To systematically identify genes contributing to ERα expression and signalling in breast cancer, we performed a genome-wide screen in human ERα+ luminal breast cancer cell lines stably expressing estrogen-induced luciferase reporters using an arrayed format. A primary screen (Sigma Mission lentiviral library, 16083 genes, three shRNA/gene) and secondary screens (615 genes identified as hits by at least two shRNAs with concordant impact on reporter gene expression without major effects on cell survival) were carried out using estrogen-sensitive cells (T47D-ERE3-Luc, MCF-7-ERE-Luc) and insensitive controls (antioxidant response reporter T47D-ARE-Luc). We ultimately characterized by RNASeq the impact of suppressing expression of each of 30 prioritized hits (2-3 shRNAs with >50% reduction of RNA levels per hit) on gene expression in ERα+ breast cancer cells. Knockdown of several of these hits had extensive impacts on expression of direct estrogen target genes and on ERα+ breast cancer cell proliferation. Some hits regulated ERα gene expression and several interacted with ERα in co-IP experiments, indicating roles as upstream regulators and/or transcriptional cofactors of ERα.

The importance of the training-induced decrease in basal cortisol concentration in the improvement in muscular performance in humans

Acute exercise-induced changes in cortisol concentration (C) and training related adaptation within hypothalamic-pituitary-adrenal (HPA) axis has been widely examined, but their influence on muscle strength performance is at best uncertain. Twenty four young healthy men were randomly assigned to an endurance training group (ET, n=12) or to a non-exercising controls (CON, n=12). ET performed supervised endurance training on cycle ergometer for 20 weeks. Endurance training program improved exercise capacity (14 % increase in power output generated at peak oxygen uptake - VO(2peak)), muscle strength performance (increase in MVC - maximal voluntary contraction - by 9 % and in TTF 50 % MVC - time to fatigue at 50 % MVC - by 21 %) and led to a decrease in basal serum C concentration (P=0.006) and an increase in basal testosterone to cortisol (T/C) and free testosterone to cortisol (fT/C) ratios (P=0.01 and P=0.02, respectively). It was found that the decrease in C concentration (deltaC) was positively correlated to the increase in local muscular endurance (deltaTTF 50 % MVC). No significant hormonal changes were seen in CON group. It is concluded that greater decrease in cortisol concentration after the endurance training is accompanied by poorer improvement in skeletal muscle performance in previously untrained subjects.

Rapid changes in cardiac myofilament function following the acute activation of estrogen receptor-alpha

Estrogens have well-recognized and complex cardiovascular effects, including altering myocardial contractility through changes in myofilament function. The presence of multiple estrogen receptor (ER) isoforms in the heart may explain some discrepant findings about the cardiac effects of estrogens. Most studies examining the impact of estrogens on the heart have focused on chronic changes in estrogen levels, and have not investigated rapid, non-genomic pathways. The first objective of this study was to determine how acute activation of ERα impacts cardiac myofilaments. Nongenomic myocardial estrogen signaling is associated with the activation of a variety of signaling pathways. p38 MAPK has been implicated in acute ER signaling in the heart, and is known to affect myofilament function. Thus, the second objective of this study was to determine if acute ERα activation mediates its myofilament effects through p38 MAPK recruitment. Hearts from female C57Bl/6 mice were perfused with the ERα agonist PPT and myofilaments isolated. Activation of ERα depressed actomyosin MgATPase activity and decreased myofilament calcium sensitivity. Inhibition of p38 MAPK attenuated the myofilament effects of ERα activation. ERα stimulation did not affect global myofilament protein phosphorylation, but troponin I phosphorylation at the putative PKA phosphorylation sites was decreased. Changes in myofilament activation did not translate into alterations in whole heart function. The present study provides evidence supporting rapid, non-genomic changes in cardiac myofilament function following acute ERα stimulation mediated by the p38 MAPK pathway.

Relaxin alters cardiac myofilament function through a PKC-dependent pathway

The pregnancy hormone relaxin (RLX) is a powerful cardiostimulatory peptide. Despite its well-characterized effects on the heart, the intracellular mechanisms responsible for RLX's positive inotropic effects are unknown. Cardiac myofilaments are the central contractile elements of the heart, and changes in the phosphorylation status of myofilament proteins are known to mediate changes in function. The first objective of this study was to determine whether RLX stimulates myofilament activation and alters the phosphorylation of one or more myofilament proteins. RLX works through a variety of intracellular signaling cascades in different tissue types. Protein kinases A (PKA) and C (PKC) are two common molecules implicated in RLX signaling and are known to affect myofilament function. Thus the second objective of this study was to determine whether RLX mediates its myocardial effects through PKA or PKC activation. Murine myocardium was treated with recombinant H2-RLX, and cardiac myofilaments were isolated. RLX increased cardiac myofilament force development at physiological levels of intracellular Ca2+ without altering myofilament ATP consumption. Myosin binding protein C, troponin T, and troponin I phosphorylation levels were increased with RLX treatment. Immunoblot analysis revealed an increase in myofilament-associated PKC-δ, decreases in PKC-α and -βII, but no effect on PKC-ε. Inhibition of PKC with chelerythrine chloride or PKC-δ with rottlerin prevented the RLX-dependent changes in myofilament function and protein phosphorylation. PKA antagonism with H-89 had no effect on the myofilament effects of RLX. This study is the first to show that RLX-dependent changes in myofilament-associated PKC alters myofilament activation in a manner consistent with its cardiostimulatory effects.

Endurance training of moderate intensity increases testosterone concentration in young, healthy men

The aim of this study was to investigate the effect of short-term, moderate intensity and low volume endurance training on gonadal hormone profile in untrained men. Fifteen young, healthy men performed an endurance training of 5-week duration on a cycle ergometer. Before and after the exercise program all participants completed a maximal incremental test. Concentration of testosterone (T), sex hormone-binding globulin (SHBG) and cortisol (C) as well as blood morphology were determined in venous blood samples at rest both before and after the training. The training program resulted in 3.7% improvement of maximal oxygen uptake (VO(2max)) and 8.2% improvement of power output reached at VO(2max) (PO (max)). This was accompanied by significant increase in T (from 18.84+/-5.73 nmol.l(-1) to 22.03+/-6.61 nmol.l(-1), p = 0.0004) and calculated fT concentration (from 374+/-116 pmol.l(-1) to 470+/-153 pmol.l(-1), p = 0.00005). Moreover, the training caused a significant decrease in SHBG concentration (from 34.45+/-11.26 nmol.l(-1) to 31.95+/-10.40 nmol.l(-1), p = 0.01), whereas no significant changes were found in the cortisol concentration (334+/-138 nmol.l(-1) vs. 367+/-135 nmol.l(-1) for pre- and post-training measures, respectively, p = 0.50) and T/C and fT/C ratios. We have concluded that short-term, moderate intensity and low volume endurance training can significantly increase testosterone concentration in previously untrained men.

CA125 in ovarian cancer: European Group on Tumor Markers guidelines for clinical use

CA125 is currently the most widely used tumor marker for ovarian epithelial cancer. The aim of this article is to provide guidelines for the routine clinical use of CA125 in patients with ovarian cancer. Due to lack of sensitivity for stage I disease and lack of specificity, CA125 is of little value in the detection of early ovarian cancer. At present, therefore, CA125, either alone or in combination with other modalities, cannot be recommended for screening for ovarian cancer in asymptomatic women outside the context of a randomized controlled trial. Preoperative levels in postmenopausal women, however, may aid the differentiation of benign and malignant pelvic masses. Serial levels during chemotherapy for ovarian cancer are useful for assessing response to treatment. Although serial monitoring following initial chemotherapy can lead to the early detection of recurrent disease, the clinical value of this lead-time is unclear. CA125 is the ovarian cancer marker against which new markers for this malignancy should be judged.

Vascular endothelial growth factor (VEGF) concentration in sera and tumor effusions from patients with ovarian carcinoma

VEGF is an important angiogenic cytokine with a critical role in tumor angiogenesis. VEGF concentrations were measured using an ELISA assay, detecting VEGF165 isoform, in tumor cyst and/or ascitic fluids and in sera of 86 patients with malignant neoplasms and in 53 patients with benign ovarian neoplasms. VEGF levels were significantly elevated in the sera and cyst fluids of carcinoma patients compared with patients who had benign neoplasms. In carcinoma patients, statistically higher VEGF levels were detected in tumor effusions than in corresponding sera. The differences between VEGF values in sera and tumor effusions in relation to histological subtypes of ovarian carcinoma and FIGO stages were statistically insignificant. High VEGF levels in ascitic fluids appeared to be significantly associated with shorter disease-free survival and overall survival In multivariate analysis, besides FIGO stage and age of patients, only serum VEGF concentration was an independent prognostic factor for overall survival. The elevated VEGF levels in sera and tumor effusions of patients with FIGO stages I/II indicated that angiogenesis promoted by VEGF is a continuous process, independent of clinical advancement of the disease.

Predictive value of SCC-Ag, CYFRA 21-1 and selected acute phase proteins in radiotherapy of pharyngeal and laryngeal cancer. A preliminary report

The diagnostic sensitivity and specificity of tumor markers in head and neck cancers is not satisfactory. It is a stimulus for search of other biochemical indicators, among others determinations of acute phase proteins, helpful in head and neck cancers diagnostics and prognosis. In a group of 33 patients with squamous cell carcinoma of the pharynx and larynx (T1-4 N0-3 M0) CYFRA 21-1, SCC-Ag and acute phase proteins such as prealbumin, albumin, alpha-1 acid glycoprotein, alpha-1 antytrypsin, transferrin, ceruloplasmin and C-reactive protein (CRP) determinations were performed before radiotherapy. Significantly greater area under ROC curve for CYFRA 21-1 than for SCC-Ag was found. In T3-4 group, significantly lower albumin and higher AAG and CRP concentrations in comparison with T1-2 patients were observed. Multivariate analysis revealed that apart from tumor stage, elevated concentrations of SCC-Ag and/or CRP are independent unfavorable prognostic factors.

[Results of a randomized prospective trial comparing postoperative abdominopelvic radiotherapy with postoperative chemotherapy in early ovarian cancer]

PURPOSE

In a prospective randomized trial, our aim was to evaluate and compare the tolerance and efficacy of postoperative radiotherapy and chemotherapy in the treatment of early ovarian cancer.

MATERIAL AND METHODS

Between 1990 and 1996, 150 patients with ovarian cancer stage IA, IB grades G2-3, and all patients classified IC and IIA, who did not have evidence of residual disease after surgery, were randomized to two treatment branches: radiotherapy or chemotherapy (CH). In the radiotherapy branch (76 patients), a whole abdomen irradiation of 30 Gy in 24 fractions over 5 weeks, with a pelvic boost to 50 Gy, was delivered. In the chemotherapy branch (74 patients), there were six series of polychemotherapy separated with 3-weeks interval. In each series patients received association of cisplatin (50 mg/m2, d1), adriamycin (50 mg/m2, d1) and cyclophosphamide (500 mg/m2, d1).

RESULTS

The tolerance of the treatment was good and comparable in both groups. In the radiotherapy branch, three late grade G3 intestinal complications were observed (three bowel obstructions, which required surgery in two cases). The actuarial survival rate without evidence of disease was 81% at 5 years for both groups. In our series we found that histological grade had the strongest influence on survival prognosis; it was the only significant factor in a multivariate analysis. Patients with grade G3 tumors had the worst survival.

CONCLUSION

These data suggest that efficacy of postoperative radiotherapy and chemotherapy administered to our patients with early ovarian cancer gave approximately identical results.

CYFRA 21-1, TPA-M, TPS, SCC-Ag and CEA in patients with squamous cell lung cancer and in chemical industry workers as a reference group

In etiology of lung cancer chemical carcinogenesis seems to be a very important factor. In the studies presented here the diagnostic usefulness of tumor markers in lung cancer was evaluated, using as a reference group workers of a chemical plant producing chromite and chromate pigments. The investigations of CYFRA 21-1, TPA-M, TPS, CEA and SCC-Ag were performed before treatment in a group of 76 squamous cell lung cancer patients in different stages of disease and in a reference group of 75 workers of the chemical company, who had been exposed to hexavalent chromium for longer than 1 year and had no clinical or radiological symptoms of lung diseases. In the squamous cell lung cancer group concentrations of all analyzed tumor markers were considered to be significantly higher than in the reference group. TPA assay demonstrated higher diagnostic performance than CYFRA 21-1 and the remaining tumor markers. At 0.95 specificity, the sensitivity of TPA was 0.79, CYFRA 21-1 -0.76, of TPS -0.29 whilst of CEA and SCC-Ag -0.31. The univariate analysis showed a significant prognostic value for clinical stages, only for CYFRA 21-1 and SCC-Ag. A significant relationship between marker level and survival was observed for CYFRA 21-1 as well as SCC-Ag levels. In a multivariate analysis CYFRA 21-1 and/or TPS remained significant predictors of survival.

[Radiotherapy for stage III, inoperable, asymptomatic small cell lung cancer. Final results of a prospective randomized study (240 patients)]

PURPOSE

To report the results of a prospective randomized study concerning the role of radiotherapy in the treatment of stage III, unresectable, asymptomatic non-small cell lung cancer.

MATERIAL AND METHODS

Between 1992 and 1996, 240 patients with stage III, unresectable, asymptomatic non-small cell lung cancer were enrolled in this study, and sequentially randomized to one of the three treatment arms: conventional irradiation, hypofractionated irradiation and control group. In the conventional irradiation arm (79 patients), a dose of 50 Gy in 25 fractions in five weeks was delivered to the primary tumor and the mediastinum. In the hypofractionated irradiation arm (81 patients), there were two courses of irradiation separated by an interval of four weeks. In each series, patients received 20 Gy in five fractions in five days, in the same treatment volume as the conventional irradiation group. In the control group arm, 80 patients initially did not receive radiotherapy and were only observed. Delayed palliative hypofractionated irradiation (20-25 Gy in four to five fractions in four to five days) was given to the primary tumor when major symptoms developed.

RESULTS

The two-year actuarial survival rates for patients in the conventional irradiation, hypofractionated irradiation and control group arms were 18%, 6% and 0%, with a median survival time of 12 months, nine months and six months respectively. The differences between survival rates were statistically significant at the 0.05 level.

CONCLUSION

Although irradiation provides good palliation, the results are disappointing. The comparison of conventional and hypofractionated irradiation shows an advantage for conventional schedules.

Leukemoid reaction in extremely low-birth-weight infants

The objective of this paper was to determine the incidence of leukemoid reaction and to evaluate its relationship with maternal and neonatal factors in extremely low-birth-weight (ELBW) infants. The design a case-controlled retrospective study of all live-born ELBW infants (<1000 g) over a period of 2 years, from July 1994 to June 1996. A total of 60 preterm infants were born during the study period, and are included in this report. The infants who demonstrated leukemoid reaction formed the study group, while the remainder formed the control group. Leukemoid reaction was defined as a white blood cell (WBC) count > or = 50,000/mm3. The relationship between maternal and neonatal variables and WBC counts was studied. Nine of the 60 infants studied demonstrated counts >50,000/mm3, with an incidence of 15%. There was no significant association demonstrated between maternal or neonatal variables and leukemoid reaction. Patients with leukemoid reaction had a better overall survival. Leukemoid reaction in ELBW infants is a rare and recently documented phenomenon. In our study the incidence was 15%. Although many factors have been postulated as a cause of this phenomenon, we could not demonstrate any relationship between these factors and high WBC counts, including sepsis and the use of antenatal steroids, the two most likely variables. It was interesting to note that the infants who were able to mount a leukemoid response had a better chance of survival than those who did not.

[Gas exchange, blood acid-base balance and mechanical muscle efficiency during incremental levels of exertion in young healthy individuals]

In this study we have evaluated the changes in gas exchange variables, blood acid-base balance and the mechanical efficiency of muscle in healthy young men during an incremental exercise test. Twenty-six healthy men: age 22.1 +/- 1.4 (mean +/- SD) years, body mass 73.6 +/- 7.4 kg, height 179 +/- 8 cm, were subjects in this study. The subjects performed an incremental exercise test on a cycloergometer at a pedalling rate of 70 rev.min-1. The exercise test started at a power output of 30 W, followed by an increase of power output by 30 W every 3 minutes. Gas exchange variables were measured continuously (breath by breath). Antecubital blood samples for acid-base balance variables and plasma lactate concentration [La]pl were taken at the end of each 3-minute step. The lactate threshold (LT) in this study was defined as the highest power output above which [La]pl showed a sustained increase of > 0.5 mmol.l-1.step-1. The power output at LT amounted to 127 +/- 28 W. It corresponded to 45% of the maximal power output (MPO) reached at maximal oxygen uptake (VO2 max). The oxygen uptake at the LT amounted to 1734 +/- 282 ml.min-1 and corresponded to 48% of VO2 max (3726 +/- 363 ml.min-1). The minute ventilation at the LT amounted to 47.8 +/- 7.5 l, and its increase to the level of 125.7 +/- 19.7 l reached at the MPO was obtained mainly by intensification of breathing frequency from 23.8 +/- 3.31.min-1 to 43 +/- 5.91.min-1, for LT and MPO respectively. Analysis of the changes in PETCO2 during the incremental exercise test showed significant differences between subjects. One could recognise a group of subjects (n = 8) with high values of PETCO2 (above 45 mmHg) and a group of subjects (n = 8) with lower values of PETCO2 (below 43 mmHg). However, no significant differences in exercise tolerance, expressed by the level of MPO and maximal oxygen uptake, were found between those groups of subjects. The mechanical efficiency calculated on the basis of power output/net oxygen uptake ratio during cycling at a power output of 60 W amounted to 24.1 +/- 3.8 percent, at the LT 25.8 +/- 2.1%, whereas at the maximal power output a significant (p < 0.01) drop in muscle efficiency occurred, to the value of 23.1 +/- 1.6%. This drop in muscle efficiency occurring at the MPO may be an important factor limiting exercise tolerance when performing high power output exercise.

IN CONCLUSION

The above presented data illustrate the physiological responses to incremental exercise and the level of exercise tolerance, which may serve as a reference point for the population of healthy, young physically active Polish students.

Pharyngeal acid reflux events in patients with vocal cord nodules

OBJECTIVE

Gastroesophageal reflux has been implicated in the pathogenesis of vocal cord nodules. However, a cause-and-effect relationship has not been established. Because documentation of pharyngeal acid reflux events makes this correlation more plausible, the aim of the present study was to determine the frequency of pharyngeal acid reflux events in patients with vocal cord nodules.

METHODS

Eleven patients with vocal cord nodules (mean age, 42 +/- 6 years) and eleven healthy volunteers (mean age, 45 +/- 6 years) were studied. Patients underwent barium esophagram and ambulatory 24-hour simultaneous three-site pharyngoesophageal pH monitoring. Controls only had ambulatory 24-hour simultaneous three-site pH monitoring. In the ambulatory pH monitoring studies, pH was recorded from the manometrically determined sites of pharynx (2 cm above upper esophageal sphincter), proximal esophagus (10 cm distal to pharyngeal site), and distal esophagus (5 cm above the lower esophageal sphincter). Pharyngeal acid reflux event was deemed acceptable if all three sites recorded a decrease in pH below 4 which was not related to meal or drinking.

RESULTS

Pharyngeal acid reflux events occurred in seven of 11 patients with vocal cord nodules (1-4 episodes) and two of 11 controls (1-2 episodes) (P < .05). In both groups all pharyngeal acid reflux events occurred in upright position and were not associated with belching or coughing. Barium studies documented hiatal hernia in two patients and gastroesophageal reflux in five of 11 patients. However, none of the esophageal reflux events reached the pharynx on barium esophagram.

CONCLUSIONS

Prevalence of pharyngeal acid reflux events is significantly higher in patients with vocal cord nodules compared with normal controls and suggests a contributory role for gastroesophagopharyngeal acid reflux in the pathogenesis of some vocal cord nodules.

Mutations of the FLP recombinase gene that cause a deficiency in DNA bending and strand cleavage

We have used site-directed mutagenesis to change several amino acids of the C-terminal portion of the FLP recombinase of Saccharomyces cerevisiae. These residues are absolutely conserved among the six FLP-like proteins from various yeast strains. We have examined the ability of the altered proteins to catalyze recombination in vivo and in vitro and to perform various partial steps of the reaction in vitro. Two of the mutations produced a partial defect in DNA binding but the remainder resulted in normal binding. All of these mutations caused impairment of the ability of the protein to induce the type II bend of the FRT site, and some of these proteins were also defective in DNA strand cleavage. None of the mutations affected the ability of the proteins to perform synapsis between two FRT sites, but some were defective in strand ligation. Interestingly, some mutant proteins showed impairment of the initial stages of the recombination reaction on a linear substrate and yet they maintained the ability to resolve a Holliday intermediate in the reaction. We conclude that this conserved region of the FLP protein is important for the early stage(s) of the recombination reaction.

[Value of plasma testosterone, carcinoembryonic antigen and CA 19-9 in the differential diagnosis of pancreatic carcinoma and chronic pancreatitis]

Diagnostic value was assessed of serum testosterone concentration and compared with that of serum assay of CEA and CA 19-9 in the differential diagnosis of pancreatic cancer (PC) and chronic pancreatitis (CP). Thirty-six patients with PC were compared with thirty-two CP patients. The sensitivity of CA 19-9 (76.9%) in detecting PC was greater than that of testosterone and CEA (30.6% and 30.8%, respectively). The specificity of testosterone and CA 19-9 were comparable (93.7% and 96.4%, respectively). The combination of tests did not enhance the sensitivity and specificity of each test when used alone. The serum CA 19-9 concentration in PC patients was significantly higher then in patients with colon cancer, gastric cancer and benign gastrointestinal diseases.

Characterization of the hemolysin transporter, HlyB, using an epitope insertion

The prokaryotic hlyB gene product is a member of a superfamily of ATP-binding transport proteins that include the eukaryotic multidrug-resistance P-glycoprotein, the yeast STE6, and the cystic fibrosis CFTR gene products (Juranka, P. F., Zastawny, R. L., and Ling, V. (1989) FASEB J. 3, 2583-2592). Previous genetic studies have indicated that HlyB is involved in the transport of the 107-kDa HlyA protein from Escherichia coli; however, the HlyB protein has not been purified for biochemical studies due to its low abundance. In this study, we have engineered a monoclonal antibody epitope into the C-terminal end of HlyB that did not destroy its function. This has allowed us to use immunological methods to identify and localize various molecular forms of the HlyB protein present in vivo.

CA-50 serum level in patients with prostate cancer

CA-50 antigen is considered to be a generalized carcinoma-associated antigen. CA-50 serum levels were measured by solid phase radioimmunoassay using a specific monoclonal antibody. Sera of 49 patients with prostatic cancer of different clinical stages, 43 patients suffering from BPH, and 28 healthy males were tested. Positive test results were observed in 57.1% of patients with prostate cancer values ranging from 42.9% in stage A to 66.7% in stage D. Increased CA-50 levels were found in 11.6% of patients with BPH.

Potassium-dependent changes in the expression of membrane-associated proteins in barley roots : I. Correlations with k(rb) influx and root k concentration

Barley (Hordeum vulgare L. cv Halcyon) seedlings which had been grown in full strength complete inorganic nutrient media (containing 6 millimolar K(+)) had high internal K(+) concentrations and low values of K(+) ((86)Rb(+)) influx when influx was measured from solutions containing 100 micromolar K(+). Transfer of these plants to solutions lacking K(+) resulted in significant reductions of root and shoot K(+) concentrations and values of K(+) ((86)Rb(+)) influx increased by greater than 10-fold within 3 days. When plants treated in this way were returned to complete solutions, containing K(+), the changes induced by K(+) deprivation were reversed. Parallel studies of microsomal membranes by means of SDS-PAGE demonstrated that the expression of a group of polypeptides increased or decreased in parallel with changes of K(+) ((86)Rb(+)) influx. Most prominent of these were 45 and 34 kilodalton polypeptides which specifically responded to K(+) status of the barley plants; their expression was not enhanced by N or P deprivation. The 45 kilodalton polypeptide was susceptible to degradation by a membrane associated protease when microsomes were washed in buffer containing 0.2 millimolar PMSF. This loss was prevented by increasing PMSF concentration to 2 millimolar.

Characterization of a protein serine kinase from yeast plasma membrane

A casein kinase activity, which copurifies with the H+-ATPase activity during isolation of plasma membranes Saccharomyces cerevisiae and during centrifugation of the solubilized membrane extract through a sucrose gradient, is separated from the Mr = 100,000 ATPase catalytic polypeptide by subsequent DEAE-cellulose chromatography. The purified casein kinase activity exhibits a low Km of 12 microM MgATP, is maximally stimulated by 6 mM free Mg2+, and is 50% inhibited by 300 microM Zn2+, by 7.5 micrograms of heparin/ml, and by 300 microM orthovanadate. It phosphorylates only seryl residues. The purified casein kinase contains two polypeptides of Mr = 45,000 and 39,000 which yield antibodies which do not cross-react to each other. The two polypeptides seem to originate from a precursor of Mr = 85,000 which is detected by both antibodies in partly purified fractions. In the absence of casein, a zinc and heparin-sensitive phosphorylation of the ATPase polypeptide is observed in partly purified ATPase fractions, and a peptide of similar mobility is phosphorylated, among others, in isolated plasma membranes. The purified ATPase activity is markedly inhibited by incubation in the presence of acid phosphatase. In agreement with a recent report that the purified active ATPase molecule is largely phosphorylated (Yanagita, Y., Abdel-Ghany, M., Raden, D., Nelson, N., and Racker, E. (1987) Proc. Natl. Acad. Sci. U. S. A. 894, 925-929) this data suggests that dephosphorylation leads to deactivation of ATPase activity.

Serum tissue polypeptide antigen (TPA) and prostatic acid phosphatase (PAP) in patients with prostatic cancer

Concurrent measurements of serum TPA and PAP concentrations by double antibody radioimmunoassays were done in 49 patients with prostatic cancer in different clinical stages. The reference group comprised patients suffering from BPH. Positive TPA was found in 32.7% of cancer patients, the lowest percentage in stage A (11.1%) and the highest in stage D (55.6%). The additional value as a diagnostic aid of the TPA test was revealed on the basis of examination of the selected group of patients with not increased PAP. Positive TPA was found in 16.7% of patients: none in stage A, 22.2% in stage B, and 33.3% in stage D. Prostatic cancer remains the most common malignancy of the genitourinary tract. The improvement in the results of treatment involves not only a modernization of treatment modalities but also the introduction of laboratory tests which give the most ample information on the stage of tumour development and improve possibilities to control tumour therapy. Besides the refinement of the determination procedures of specific prostatic markers, prostatic acid phosphatase (PAP), through radio- and enzyme-immunological methods, there is a search for additional markers which might be helpful in diagnosis and follow-up of treatment.

A single mutation confers vanadate resistance to the plasma membrane H+-ATPase from the yeast Schizosaccharomyces pombe

A single-gene nuclear mutant has been selected from the yeast Schizosaccharomyces pombe for growth resistance to Dio-9, a plasma membrane H+-ATPase inhibitor. From this mutant, called pma1, an ATPase activity has been purified. It contains a Mr = 100,000 major polypeptide which is phosphorylated by [gamma-32P] ATP. Proton pumping is not impaired since the isolated mutant ATPase is able, in reconstituted proteoliposomes, to quench the fluorescence of the delta pH probe 9-amino-6-chloro-2-methoxy acridine. The isolated mutant ATPase is sensitive to Dio-9 as well as to seven other plasma membrane H+-ATPase inhibitors. The mutant H+-ATPase activity tested in vitro is, however, insensitive to vanadate. Its Km for MgATP is modified and its ATPase specific activity is decreased. The pma1 mutation decreases the rate of extracellular acidification induced by glucose when cells are incubated at pH 4.5 under nongrowing conditions. During growth, the intracellular mutant pH is more acid than the wild type one. The derepression by ammonia starvation of methionine transport is decreased in the mutant. The growth rate of pma1 mutants is reduced in minimal medium compared to rich medium, especially when combined to an auxotrophic mutation. It is concluded that the H+-ATPase activity from yeast plasma membranes controls the intracellular pH as well as the derepression of amino acid, purine, and pyrimidine uptakes. The pma1 mutation modifies several transport properties of the cells including those responsible for the uptake of Dio-9 and other inhibitors (Ulaszewski, S., Coddington, A., and Goffeau, A. (1986) Curr. Genet. 10, 359-364).

Bone marrow cyclic nucleotides (cAMP, cGMP) in phenylhydrazine-induced anemia

The studies were carried out on male Wistar rats. The animals were divided into two groups: control and experimental. The hematocrit value and reticulocyte count were determined in blood samples collected from control and experimental rats. The experimental rats received subcutaneous injections of phenylhydrazine manufactured by Sigma for the duration of 3 days. On the 5th day blood samples were collected from all the control and experimental animals and determinations of hematocrit and reticulocyte count were repeated. cAMP levels were determined in bone marrow extracts by means of a radiocompetitive method. The cGMP level was determined by a radioimmunological assay. A significant elevation of cAMP level was detected in experimental rats, whereas the cGMP level changed only slightly.

The concentration of zinc in relation to fundamental elements in the diseased human prostate

Studies of the composition of prostatic tissue revealed significant decreases not only of the zinc but also of the potassium concentration, in the cancerous tissue, whereas the nitrogen, phosphorus and magnesium concentrations were within normal limits. The composition of hyperplastic prostatic tissue was similar to the normal except for a tendency towards decreased nitrogen concentration.

Transfusion of granulocyte rich buffy coats to neutropenic patients

Granulocyte rich buffy coats were transfused to infected neutropenic patients when leukapheresis donors were not available. Efficacy of transfusions was evaluated from data supplied by hospitals administering them. Buffy coats separated from ACD blood contained a mean of 4.9 X 10(8) granulocytes. Fifty-seven patients received a course consisting of a mean of 3.8 transfusions. Of these, 27 received a mean of 17.5 units per transfusion and had a survival rate of 44.4%, which was not significantly different from the 50.0% found in 30 who received a mean of 11.1 units per transfusion. No significant difference in survival rate was found between 31 patients with acute leukemia and 26 with other disorders or 38 patients with positive and 19 with negative cultures. Finally, no significant difference in survival rate was noted between patients who received a course of greater than or equal to four transfusions or less than or equal to three transfusions in any of the above groups. Survival rates were less than those generally reported following similar courses of leukapheresis units. Buffy coat transfusions consisting of a mean of approximately 17.5 units as produced during this study have therefore been shown to be not generally beneficial. The increased survival seen in some studies utilizing leukapheresis products may relate in part to the larger number of granulocytes they contained. Greater benefit from buffy coat transfusions might result if the number of granulocytes infused were increased. Evaluation of possible efficacy associated with transfusions of increased numbers of buffy coat units further enriched with granulocytes may be justified when leukapheresis donors are not available.

Modification of psychotic speech with mentally retarded patients

Three chronic schizophrenics who were mild to severely mentally retarded were treated for a wide range of vocalisations characteristic of psychotic persons. Relevance of responses, speech duration, making nonsense statements, and changing the subject were among the behaviours treated in two experiments. Treatment consisted of instructions, performance feedback via audiotapes, modelling and speech rehearsal provided in twenty-five minute training sessions held each day on a one-to-one basis with a therapist. In all cases, treatment resulted in rapid changes of target behaviours in desired directions. Results were particularly significant since all three subjects displayed active hallucinations and delusions while taking large maintenance dosages of antipsychotic medications. Changes generalised across settings and were maintained over two months follow-up.

Altered platelet function and circulation induced by amphotericin B in leukemic patients after platelet transfusion

Four adults, recently diagnosed, acute leukemic patients received 40 separate platelet transfusion treatments before, during, and after intravenous administration of amphotericin B. Fourteen of these platelet transfusions were administered while the patients also received amphotericin B; 26 platelet transfusions were given before or after amphotericin B therapy. The mean platelet increment for platelet transfusions administered while the patients were untreated with amphotericin B was 58 +/- 6 per cent. While the same patients were being treated with amphotericin B, the mean platelet increment was significantly decreased to 29 +/- 8 per cent (t = 3.1; p less than 0.005). In addition, when the patients were not being given amphotericin B, a highly significant negative relationship (r = -0.77; p less than 0.001) between the values for bleeding time and venous platelet count was present. In contrast, during amphotericin B treatment there was no correlation between the patients' bleeding times and venous platelet counts. We propose that amphotericin B therapy has a direct toxic effect on the function and circulation of transfused platelets. These toxic effects are quickly corrected by discontinuing this antifungal antibiotic.