Assessment of hormone refractory prostate cancer

OBJECTIVES

To define guidelines for the assessment of treatment in patients with hormone-refractory prostate cancer (HRPC).

METHODS

In the light of modern research, and taking new treatment options into account, the Committee essays to specify different categories of patients entering clinical trials, and to define response criteria and those endpoints that are relevant in phase III studies and in short-term follow-up.

RESULTS

HRPC comprises a range of disease states with varying responsiveness to therapy and length of survival. Patients with progression as evaluated by increasing prostate-specific antigen (PSA) values alone have a more favorable prognosis than those presenting with increasing tumor spread. In the assessment of these patients, the modes of previous therapy and the kind of tumor progression must be taken into account. The benefit of treatment of HRPC is often modest. While duration of survival remains the main and ultimate endpoint, the means of measuring short-term responsiveness to therapy are limited. A minority of patients have measurable tumor lesions. Decrease of PSA or other biochemical tumor markers may indicate depression of the tumor activity, but is not always associated with prolongation of survival. A variety of new treatments in HRPC are being investigated. They affect measurable tumor parameters in different ways.

CONCLUSIONS

When a new agent is to be tested, it is important to measure all possible parameters before deciding which particular ones are appropriate for future investigations of this agent. In symptomatic patients, evaluation of subjective parameters, for example, relief of pain or improvement of performance status, is often the most reliable measure of treatment effect. However, these parameters should be clearly defined.

A method for studying the effects of neurochemicals on long-term compensation in unilaterally labyrinthectomized rats

A new method has been developed to study the influence of drugs and toxicants on long-term recovery of dynamics in the horizontal vestibulo-ocular reflex of the rat after hemilabyrinthectomy (HL). HL was performed by injecting sodium arsanilate into the middle ear. The lesion was confirmed by histology. Eye movements elicited by sinusoidal vestibular stimulation, in both light and darkness, were recorded by a search-coil technique and then analyzed by a computer program created with virtual instrument soft-ware, which calculated the gain of the slow-phase velocity (SPV) and the saccades para-meters (frequency, amplitude, and peak velocity) to the lesioned side and to the intact side separately. During the 2-10 week period after HL, repeated analysis of the spontaneous long-term recovery of such parameters revealed a slight but significant reduction of the post-HL asymmetry between SPV gain to the lesioned side and to the intact side. During the follow-up period, a post-HL increase of the phase lead remained unchanged. The reduced number of saccades/min was not completely restored. To test the usefulness of the experimental model for neurochemical investigation of such adaptation, we administered baclofen and toluene to rats 8-12 wk after hemilabyrinthectomy. Baclofen, a specific GABAB agonist, immediately restored the symmetry of SPV gain. By contrast, toluene, which has some effects on the central vestibular system that are related to GABAB transmission, aggravated the asymmetry in both the SPV gain and the number of saccades. We suggest that the experimental model would be useful for studying neurochemical mechanisms in vestibular adaptation processes.

Laparoscopy aided gastrostomy in children

BACKGROUND AND AIMS

The aim of this report is to describe a method for laparoscopy aided button gastrostomy in children.

MATERIAL AND METHODS

The method includes the use of two ports, one umbilical and one subcostal on the left side. The stomach is exteriorized using a grasping forceps in the subcostal port. Under direct vision the gastrostomy button, MIC-KEY, is inserted into the stomach at the lesser curvature and secured by purse string sutures. The stomach is attached to the anterior abdominal wall.

RESULTS

The results show that this method has been successfully used in 33 children without operative complications.

CONCLUSIONS

We conclude that by inserting the gastrostomy button under direct vision, damage to other abdominal organs is avoided and a correct placement at the lesser curvature obtained. The combination of laparoscopic and open procedures makes the method easy and safe.

Traumatic oral vs non-oral injuries

This study comprised patients who sought consultation or treatment from a physician or dentist for injury caused by accident in a Swedish county (Västmanland 256510 inhabitants) during a period of one year. A total of 23690 (adjusted for non-responders) individuals were injured during the study period. Five per cent included oral injuries, 95% non-oral injuries, and 0.4% consisted of both oral and non-oral injuries. In total, oral injuries were the sixth most common part of the body that was injured. The incidence of oral injuries was 4.2/1000 inhabitants/year and of non-oral injuries 87.8/1000/year. Because practically all oral injuries were observed in individuals under the age of 30, the comparison between oral and non-oral injuries was made for the age interval 0-30 years. The highest risk of sustaining oral injuries was in the ages 0-12 years, where the annual incidence was 18/1000, making oral injuries the third most common form of injury. The study reveals substantial differences between oral and non-oral injuries with regard to age-groups, site of injury, and injury mechanism. Falls were the most common cause of oral injuries among those 0-6 years of age, whereas push and hit were the primary causes of oral injuries in the ages 16-30 years. Non-oral injuries were caused most frequently by falls in all age groups. Alcohol and violence were more likely related to oral than non-oral injuries for persons in the age interval 16-30 years. The number of oral injuries was higher during weekends and in the late evenings than at other times, whereas most non-oral injuries occurred during day-time hours, and were spread evenly throughout the week. The high incidence and special characteristics of oral injuries stress the importance of including oral injuries to achieve a high validity in body injury surveillance systems. Furthermore, the results indicate that epidemiological data are unique for oral injuries which should be taken into consideration when planning for prevention and organization of emergency resources.

A missense mutation in the gene for melanocyte-stimulating hormone receptor (MC1R) is associated with the chestnut coat color in horses

The melanocyte-stimulating hormone receptor gene (MC1R) is the major candidate gene for the chestnut coat color in horses since it is assumed to be controlled by an allele at the extension locus. MC1R sequences were PCR amplified from chestnut (e/e) and non-chestnut (E/-) horses. A single-strand conformation polymorphism was found that showed a complete association to the chestnut coat color among 144 horses representing 12 breeds. Sequence analysis revealed a single missense mutation (83Ser-->Phe) in the MC1R allele associated with the chestnut color. The substitution occurs in the second transmembrane region, which apparently plays a key role in the molecule since substitutions associated with coat color variants in mice and cattle as well as red hair and fair skin in humans are found in this part of the molecule. We propose that the now reported mutation is likely to be the causative mutation for the chestnut coat color. The polymorphism can be detected with a simple PCR-RFLP test, since the mutation creates a TaqI restriction site in the chestnut allele.

Pet birds and risk of lung cancer in Sweden: a case-control study

OBJECTIVE

To investigate the association between keeping birds and the risk of lung cancer in Sweden.

DESIGN

Case control study based on cases of lung cancer and community controls. Interviews were performed by two nurses specially trained for this project.

SETTING

Three major referral hospitals located in southwest Sweden.

SUBJECTS

All patients aged 75 and under with newly diagnosed lung cancer and of Scandinavian birth who lived in one of 26 municipalities in Gothenburg and Bohus county or Alvsborg county. Potential control subjects matched on county of residence, sex, and closest date of birth were selected from population registries. In the context of a larger case-control study, information on pet birds was obtained from 380 patients with lung cancer (252 men) and 696 controls (433 men).

MAIN OUTCOME MEASURES

Odds ratios for lung cancer in relation to whether or not pet birds were kept and the duration of keeping pet birds.

RESULTS

The adjusted odds ratio for ever versus never exposed to pet birds at home was 0.94 (95% confidence interval 0.64 to 1.39) for men and 1.10 (0.64 to 1.90) for women. There was no evidence of a trend for increased risk of lung cancer with duration of bird ownership.

CONCLUSION

Bird keeping does not seem to confer any excess risk of lung cancer to Swedish men or women.

Influence of age, gender, and blood-alcohol concentration on the disappearance rate of alcohol from blood in drinking drivers

The rate of disappearance of alcohol from the blood (beta-slope) was determined in drinking drivers by taking two blood samples about 60 min apart (mean 68 min, span 30 to 120 min). The results were compared for men and women as a function of their age and the prevailing blood-alcohol concentration (BAC). The material consisted of 1090 double blood samples from 976 men and 114 women with mean age 36.6 +/- 12.9 y (+/- SD) and 38.0 +/- 12.3 y (+/- SD), respectively. The mean BAC for the male DUI suspects was 1.88 +/- 0.748 mg/mL (+/- SD) compared with 1.86 +/- 0.702 (+/- SD) for the females. The relationship between beta-slope (y) and BAC (x) was y = 0.175 + 0.009x with a small positive correlation (r = 0.13) and standard error estimate (Syx) of 0.049 mg/mL. The mean beta-slope for female DUI suspects was 0.214 +/- 0.053 mg/mL/h (+/- SD), compared with 0.189 +/- 0.048 mg/mL/h in the male suspects, and this small difference was statistically highly significant (t = 5.21, p < 0.001). The overall mean rate of alcohol elimination from blood in drinking drivers was 0.191 +/- 0.049 mg/mL/h (+/- SD), and the 95% limits of agreement (LOA) spanned from 0.09 to 0.29 mg/mL/h. The value of the beta-slope was slightly steeper starting from a high initial BAC but was not much influenced by the person's age.

Pigs with the dominant white coat color phenotype carry a duplication of the KIT gene encoding the mast/stem cell growth factor receptor

Comparative mapping data suggested that the dominant white coat color in pigs may be due to a mutation in KIT which encodes the mast/stem cell growth factor receptor. We report here that dominant white pigs lack melanocytes in the skin, as would be anticipated for a KIT mutation. We found a complete association between the dominant white mutation and a duplication of the KIT gene, or part of it, in samples of unrelated pigs representing six different breeds. The duplication was revealed by single strand conformation polymorphism (SSCP) analysis and subsequent sequence analysis showing that white pigs transmitted two nonallelic KIT sequences. Quantitative Southern blot and quantitative PCR analysis, as well as fluorescence in situ hybridization (FISH) analysis, confirmed the presence of a gene duplication in white pigs. FISH analyses showed that KIT and the very closely linked gene encoding the platelet-derived growth factor receptor (PDGFRA) are both located on the short arm of Chromosome (Chr) 8 at band 8p12. The result revealed an extremely low rate of recombination in the centromeric region of this chromosome, since the closely linked (0.5 cM) serum albumin (ALB) locus has previously been in situ mapped to the long arm (8q12). Pig Chr 8 shares extensive conserved synteny with human Chr 4, but the gene order is rearranged.

Variability of the blood/breath alcohol ratio in drinking drivers

The ratio of blood-alcohol concentration (BAC) to breath-alcohol concentration (BrAC) was determined for 799 individuals apprehended for driving under the influence of alcohol (DUI) in Sweden. The BrAC was determined with an infrared analyzer (Intoxilyzer 5000S) and venous BAC was measured by headspace gas chromatography. The blood samples were always taken after the breath tests were made and the average time delay was 30 +/- 12 min (+/- SD), spanning from 6 to 60 min. The blood/breath ratios of alcohol decreased as the time between sampling blood and breath increased (F = 15.4, p < 0.001), being 2337 +/- 183 (6 to 15 min), 2302 +/- 202 (16 to 30 min), 2226 +/- 229 (31 to 45 min), and 2170 +/- 225 (46 to 60 min). When the BAC was corrected for the metabolism of alcohol at a rate of 0.019 g%/h, the mean blood/breath ratios were 2395 +/- 193 (6 to 15 min), 2416 +/- 211 (16 to 30 min), 2406 +/- 223 (31 to 45 min), and 2407 +/- 210 (45 to 60 min); no significant differences (F = 0.197, p > 0.05). The overall mean time-adjusted blood/breath ratio (+/- SD) was 2407 +/- 213 and the 95% limits of agreement (LOA) were 1981 and 2833. During 1992, 1993, and 1994, the mean blood/breath ratios of alcohol were remarkably constant, being 2409 +/- 288, 2407 +/- 206, and 2421 +/- 235, respectively, and the values were not significantly influenced by the person's age, gender, or blood-alcohol content. In 34 individuals (4.3%), the blood/breath ratio was less than 2100 after compensating for metabolism of alcohol between the times of sampling blood and breath. This compares with 156 individuals (19.6%) having a blood/breath ratio less than 2100:1 without making any correction for the metabolism of alcohol.

Livestock genomics comes of age

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A new method for measuring lymphoproliferation at the single-cell level in whole blood cultures by flow cytometry

A simple and reproducible method is described for the measurement of proliferative responses to mitogens and antigens. Whole blood (WB) cultures are used and separation procedures are not necessary. Proliferative responses are monitored as development of lymphoblasts determined by flow cytometry (FC). Lymphocytes and lymphoblasts were shown to be exclusively selectable from mixed cell populations of WB by their light scatter profile on FC analysis. More than 90% of the lymphoblasts identified by FC were replicating DNA as determined by incorporation of the thymidine analogue 2-bromo-5-deoxyuridine. The WB/FC technique can be combined with triple immunofluorescence which was illustrated by determining subsets of lymphoblasts developing following stimulation with various mitogens and antigens. The new method was compared with the conventional method (peripheral blood mononuclear cell culture and proliferation measured by detection of DNA synthesis). The reproducibility of the methods were not different. The antigen-induced responses recorded by both methods correlated, but with significantly higher stimulation indices obtained by WB/FC. The latter procedure was also technically easier to perform and less time-consuming.

Pancreatic lipase-related protein 2 but not classical pancreatic lipase hydrolyzes galactolipids

The pancreatic lipase family contains three subfamilies, the 'classical' lipases and the pancreatic lipase-related proteins 1 (PLRP1) and 2 (PLRP2). Galactolipids are present in membranes of leaves and vegetables and consist of digalactosyldiacylglycerol (DGalDG) monogalactosyldiacylglycerol (MGalDG) and sulfoquinovosyldiacylglycerol (SQDG). These lipids were incubated with PLRP2 from guinea-pig (GPLRP2) and rat (RPLRP2). In the presence of bile salts DGalDG was efficiently hydrolyzed by GPLRP2 and, although less efficiently, by RPLRP2 to digalactosylmonoacylglycerol (DGalMG), free fatty acids and water-soluble galactose-containing compounds. Also, MGalDG and SQDG were hydrolyzed by GPLRP2 and RPLRP2. These data suggest a possible role of PLRP2 in the digestion of dietary galactolipids.

The PCR typing of MHC-DRB genes in the sheep using primers for an intronic microsatellite: application to nematode parasite resistance

The strong association between polymorphisms in an intronic microsatellite and the coding sequences for (BoLA)-DRB3 genes, previously described for demonstrating alleles of class II major histocompatibility complex (MHC) in the cow, was examined in sheep to see if similar polymorphisms could be demonstrated in the DRB region of the MHC. The bovine primes LA53 and LA54, previously used to amplify the bovine DRB3 microsatellites, were used with DNA from Australian sheep, eight DRB alleles were identified by length polymorphisms of polymerase chain reaction (PCR) products amplified from the DRB microsatellite region. Incomplete amplification of both alleles was sometimes found for sheep DNA samples using bovine primers, so a modified primer (LA53b) was used, and found to amplify the microsatellite next to intron 2 of the MHC more reliably than the LA53 primer. Two additional primers (LA31 and LA32), used in amplification of the exon 2 region of bovine DRB3, were used in the sheep, and the PCR products were analysed by single-stranded conformation polymorphism (SSCP). These primers successfully amplified the variable region of the ovine DRB region coded by exon 2, and the SSCP technique demonstrated polymorphisms with sheep DNA. Family studies demonstrated the segregation of alleles, by amplification both of intronic microsatellites and of the exon 2 variable region. Close correspondence was found between the two regions for several alleles, suggesting that the intronic microsatellites were closely linked to DRB-variable region alleles. Three families of Merino sheep with different antibody responses to intestinal nematode parasites were examined. The sire group with the highest antibody levels possessed two microsatellite alleles of closely similar length (alleles 3 and 4) inherited from the sire and present in high frequency in the lambs. In contrast, the other two sires did not possess these two alleles and the alleles were in low frequency in their progeny. Further studies are required in unrelated sheep to confirm whether these two alleles are associated with resistance to nematode parasites.

A comprehensive linkage map of the pig based on a wild pig-Large White intercross

A comprehensive linkage map, including 236 linked markers with a total sex-average map length of about 2300 cM, covering nearly all parts of the pig genome has been established. Linkage groups were assigned to approximately all 18 autosomes, the X chromosome and the X/Y pseudoautosomal region. Several new gene assignments were made including the assignment of linkage group U1 (EAK-HPX) to chromosome 9. The linkage map includes 77 types I loci informative for comparative mapping and 72 in situ mapped markers physically anchoring the linkage groups on chromosomes. A highly significant heterogeneity in recombination rates between sexes was observed with a general tendency towards an excess of female recombination. The average ratio of female to male recombination was estimated at 1.4:1 but this parameter varied between chromosomes as well as between regions within chromosomes. An intriguing finding was that blood group loci were overrepresented at the distal ends of linkage groups.

The extension coat color locus and the loci for blood group O and tyrosine aminotransferase are on pig chromosome 6

A linkage map of pig chromosome 6 was constructed using a wild pig/Large White intercross pedigree. The map comprises 23 polymorphic loci, and the sex-average map length is approximately 170 cM. The study adds three new genes to the chromosome 6 map: the extension (E) coat color locus, and the blood group O (EAO) and tyrosine aminotransferase (TAT) loci. Segregation at the E locus determined two coat color phenotypes among the F2 animals: wild-type color (El-) and black-spotting (Ep/Ep). The E locus showed close genetic linkage to the most distal marker (S0035) on the short arm of chromosome 6. Comparative coat color genetics as well as comparative mapping strongly suggest that E in pigs encodes the melanocyte-stimulating hormone receptor, as previously shown for the corresponding coat color loci in mouse and cattle. TAT was also mapped to the distal part of 6p, whereas EAO was the most distal marker on 6q. A clear tendency for a higher recombination rate in both terminal regions was observed. A model for the evolution of pig chromosome 6, based on comparative mapping data, is presented.

Monomeric human red cell glucose transporter (Glut1) in non-ionic detergent solution and a semi-elliptical torus model for detergent binding to membrane proteins

The self-association state of the human red cell glucose transporter (Glut1) in octaethylene glycol n-dodecyl ether (C12E8) and n-octyl beta-D-glucopyranoside (OG) solution was analyzed in the presence of reductant by gel filtration with light-scattering, refractivity and absorbance detection, and by ultracentrifugation. The C12E8-Glut1 complex was essentially monomeric, whereas OG-Glut1 also formed dimers and larger oligomers. C12E8-Glut1 retained substantial glucose transport activity even after depletion of endogenous lipids by gel filtration, as shown by reconstitution and transport measurements. Removal of endogenous lipids from OG-Glut1 abolished the activity unless phosphatidylcholine was included in the eluent. The binding of C12E8 and OG to Glut1 was determined by gel filtration with refractivity and absorbance detection or with radioactive tracer to be 1.86 +/- 0.07 and 1.84 +/- 0.09 g/g polypeptide, respectively. A structural model was proposed in which non-ionic detergent forms a semi-elliptical torus (SET) surrounding the transmembrane protein. The torus thickness was assumed to be equal to the radius (short half-axis) of a spherical (oblate ellipsoidal) free detergent micelle and the polar head groups of the detergent molecules were predicted to be situated just outside the hydrophobic surface of the protein. The experimental detergent binding values and those obtained from the SET model together confirmed that Glut1 was monomeric in C12E8 solution and provided constraints on the shape and size of the hydrophobic transmembrane region of Glut1 in alpha-helical and beta-barrel topology models.

Impact of plasmid presence and induction on cellular responses in fed batch cultures of Escherichia coli

Fed batch cultivations of plasmid-free and recombinant Escherichia coli were employed in order to determine cellular responses and effects of plasmid presence and induction on the host cell physiology. While plasmid presence was shown to have minor influence on overall biomass yield, induction with 0.1 mM IPTG led to a marked reduction. The number of dividing cells, measured as colony forming ability, was influenced by plasmid presence and to a larger extent by induction. The latter caused a decline in the number of dividing cells to less than 10% of the population within 10 h. However, this cell segregation did not affect the specific rate of product formation, which was approximately constant throughout the cultivations. Analysis of the in vivo degradation rate of the product indicated that it was proteolytically stable. The cellular content of the stringent response signal substance, ppGpp, peaked immediately after transition from batch to fed batch mode to stabilise at a higher value than in the batch phase. When the specific growth rate declined below 0.06 h-1 an additional rise in ppGpp concentration was observed.

Report of the first workshop on the genetic map of bovine chromosome 23

A report of the first workshop on the genetic map of bovine chromosome 23 (BTA23) is given. Five laboratories contributed data from 29 loci, including a total 11586 informative genotypes. The combined pedigrees represented 1930 potentially informative meioses. Eighteen of the 29 loci were common to two or more data sets and were used to construct a framework linkage map of BTA23. Twelve of the 18 could be ordered on the linkage map with a likelihood ratio of greater than 1000:1. Thus, a low resolution consensus map was constructed with a high level of support for order. The sex-averaged, female and male maps span 54.5, 52.7 and 55.8 cM, respectively. Sex-specific differences in recombination frequency were identified for eight pairs of framework loci. Average genetic distance between framework loci on the sex-averaged map is 5.0 cM.

Cell segregation and lysis have profound effects on the growth of Escherichia coli in high cell density fed batch cultures

Cell segregation into nondividing states and lysis was found to dominate the growth behavior of high cell density fed batch cultures of Escherichia coli. When the specific growth rate declined below a critical value, the biomass production, oxygen consumption, and carbon dioxide formation rates declined sharply. Concomitantly, an extensive loss of colony-forming ability (cfu) and accumulation of extracellular proteins was observed. A segregated model that considered different physiological states, including dividing, nondividing, and lysed cells, was developed and applied to experimental data from high cell density cultures of E. coli.