Cardiovascular changes associated with decreased aerobic capacity and aging in long-distance runners

Summary Fifty-five male runners aged between 30 to 80 years were examined to determine the relative roles of various cardiovascular parameters which may account for the decrease in maximal oxygen uptake ( ) with aging. All subjects had similar body fat composition and trained for a similar mileage each week. The parameters tested were , maximal heart rate (HR _max), cardiac output (Q), and arteriovenous difference in oxygen concentration (C _a —C _ˉv) O₂ during graded, maximal treadmill running. Average body fat and training mileage were roughly 12% and 50 km·week⁻¹, respectively. The average 10-km runtime slowed significantly by 6.0%·decade⁻¹ {[10-km run-time (min)=0.323 x age (years)+24.4] (n=49,r=0.692,p<0.001)}. A strong correlation was found between age and {[ (ml·kg⁻¹·min⁻¹)=- 0.439xage+76.5] (n=55,r=-0.768, p<0.001)}. Thus, decreased by 6.9%·decade⁻¹ along with reductions ofHR _max (3.2%·decade⁻¹, p<0.001) andQ (5.8%·decade⁻¹, p<0.001), while no significant change with age was observed in estimated (C _a —C _ˉv) O₂. It was concluded that the decline of with aging in runners was mainly explained by the central factors (represented by the decline ofHR andQ in this study), rather than by the peripheral factor (represented by (C _a —C _ˉv) O₂). This study was supported, in part, by a Research Grant on Aging and Health, Ministry of Health and Welfare, Japan, and by a Research Grant for young researchers, Meiji Life Foundation of Health and Welfare, Japan.     

Affiliation to mature B cell repertoire and positive selection can be separated in two distinct processes

Using an 'oligoclonal' model, we have previously shown that mice transgenic for a mu chain (H3) and deficient for kappa chain expression display a mature B cell repertoire largely dominated by the H3/lambda1 pair, while the four H3/lambda available combinations can be observed in the immature B cell compartment. This led us to propose the existence of a positive selection process. To test this hypothesis, we have introduced the SJL lambda locus coding for a defective lambda1 chain (lambda1(s)) that creates a dysfunctional Ig receptor complex during B cell differentiation. Our results show that the lambda1(s) defect impairs the development of mature B cells when the H3-mu transgene insert is present in the hemizygous state. This suggests that the Gly --> Val substitution present in the C(lambda)1(s) chain at position 155 is sufficient to abrogate the selection of the H3/lambda1 pair. Unexpectedly, when the H3-mu transgene array is present in a homozygous state in lambda1(s) mice but not in 'wild-type' lambda1 mice (lambda1(+)), a significant number of mature B cells expressing all H3/lambda combinations can be developed. These results indicate that the overriding H3/lambda1 dominance observed in lambda1(+) mice is due to a positive selection process and not to a negative selection of other H3/lambda combinations. They also show that the export of B cells to the periphery can be controlled by the expression of the mu chain.     

Determination of specific oxygen uptake rates in human hematopoietic cultures and implications for bioreactor design

Oxygen plays an important role in the cultivation of primary cellsex vivo. In this study, we used hermetically sealed tissue culture well inserts equipped with oxygen electrodes to measure the oxygen utilization of cultured human bone marrow mononuclear cells (BM MNCs). The oxygen uptake rate (OUR) of BM MNCs was determined during a 14-day culture in which both adherent and nonadherent cells were present. Early in the culture, the cells exhibited very low OURs. The specific OURs (uptake rate per cell) were at approximately 0.005 μmol/10⁶ cells/hr shortly after the initiation of culture. The OUR then increased as the cultures developed. After about 8 to 10 days of cultivation the specific OURs had increased to 0.038±0.006 and 0.025±0.005 μmol/10⁶ cells/hr for adherent and nonadherent cells, respectively, after which no further increase was observed. Based on these oxygen uptake rate data, a mathematical model of oxygen diffusion was formulated and use to investigate issues associated with hematopoietic bioreactor design, including initial cell density, medium depth, reactor configuration, and oxygen partial pressure.In situ OUR measurements confirmed predicted oxygen limitations based on the mathematical model and the experimentally determined OURs. High-density hematopoietic cultures present design challenges in terms of sufficient and uniform delivery of oxygen to an active hematopoietic culture. These challenges can be met by using parallelplate bioreactors with thin liquid layers.     

The prognostic value of Ki67 immunostaining in non-Hodgkin's lymphoma

The monoclonal antibody Ki67 recognizes an antigen expressed in all phases of the cell cycle except Go. It has been used in 141 biopsies from 138 patients with non-Hodgkin's lymphoma to identify proliferating cells in histological sections. A Ki67 index (the number of Ki67 positive tumour cells divided by the sum of Ki67 positive and negative tumour cells) has been derived by counting 1000 cells in each case. A correction for the presence of non-tumour cells has been incorporated by counting non-tumour cells in serial sections stained with a panel of other antibodies. A very strong correlation between a low Ki67 index (less than 20 per cent) and low grade histology and a high Ki67 index (greater than 20 per cent) and high grade histology was found (Chi2 = 98.0). Ninety-one patients could be analysed for survival and those with low grade lymphoma (n = 38) who had a relatively high Ki67 index (greater than 5 per cent) had a worse survival than those with an index of less than 5 per cent (p less than 0.05). In contrast, there was a trend for those patients with high grade disease with a very high Ki67 index (greater than 80 per cent) to have a better survival than those with a lower index (less than 80 per cent). The patients with high grade disease who achieved complete remission or good partial remission and had a Ki67 index of less than 80 per cent were more likely to relapse than those with an index of greater than 80 per cent (p less than 0.04). These findings could not be explained by the effect of other prognostic factors such as age, stage, or serum albumin. While the use of Ki67 immunostaining has potential drawbacks, it appears to be a simple and reproducible method of determining a tumour proliferative index which provides relevant clinical data.     

Antikörperbildung gegen Poliovirus-N- und -H-Antigen bei Immunisierung von Meerschweinchen

Zusammenfassung Sieben Gruppen von Meerschweinchen zu je 15 Tieren wurden mit virulenten und attenuierten StÄmmen von Poliomyelitis immunisiert und die Antikörperbildung gegen N- und H-Antigen beobachtet. In allen Gruppen wurden zuerst H-Antikörper und spÄter N-Antikörper gebildet. Im weiteren Verlauf der Immunisierung nimmt bei Typ I und Typ II die Bildung von N-Antikörpern wesentlich schneller zu, so da\ die N-Titer bald höher sind als die H-Titer. Gleichzeitig reagieren zuerst mehr Versuchstiere mit H-Antikörper-Bildung, wÄhrend spÄter mehr Tiere N-Antikörper bilden.Bei der Immunisierung mit Typ III reagieren mehr Tiere mit Antikörperbildung gegen H als gegen N, gleichzeitig sind die H-Titer wÄhrend des ganzen Verlaufs höher oder ebenso hoch wie die N-Titer. Die Antikörperbildung gegen die ImpfstÄmme entsprach weitgehend dem Verlauf bei den virulenten StÄmmen. Die Reaktion des Organismus auf die Zufuhr von N- und H-Antigen Ändert sich im Laufe der Immunisierung. Die zu einem spÄteren Zeitpunkt vorgenommenen Booster-Injektionen vermögen das initiale übergewicht der H-Antikörper nicht wiederherzustellen, selbst wenn mehr H- als N-Antigen zugeführt wird.

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Antibody production versus poliovirus N and H antigen after immunisation of guinea pigs

Summary Seven groups of guinea pigs consisting of 15 animals each were immunized with virulent and attenuated strains of poliomyelitis virus. Subsequently the antibody production versus N and H antigen was studied. The animals of all groups responded primarily by production of H antibodies and later by N antibodies. During the further course of immunization the production of N antibodies was much faster for type I and II, thus anti N titers soon were higher than anti H titers. In addition, more animals responded initially by production of H antibodies, while later on more animals produce N antibodies. During the immunization with type III more animals produced H than N antibodies and H titers were always higher than N titers or equal. Antibody production to vaccination strains corresponded to a far extent to that of virulent strains. Response of the organism changes during the course of immunization. Booster injections given at a later time do not recall the initial peak of H antibodies, even if a greater dose H antigen is given than N.

     

Association between HLA and Japanese patients with rheumatoid arthritis

Japanese patients with rheumatoid arthritis (RA) were observed to have a statistical association with HLA-DR4, MT3. Strong association between the clinical severity of RA and HLA was also observed. Male patients had a stronger association with HLA than female patients. Males are more resistant to RA than females. This suggested that the threshold of liability for RA is higher in males than in females. Japanese patients with RA with systemic vasculitis were negative for HLA-Bw44 and had antilymphocytotoxic autoantibody, indicating that RA with systemic vasculitis is different in etiology from RA without systemic vasculitis.     

Ro 11-2465 (cyan-imipramine), citalopram and their N-desmethyl metabolites: Effects on the uptake of 5-hydroxytryptamine and noradrenaline in vivo and related pharmacological activities

Ro 11-2465 (cianopramine, cyan-imipramine) and citalopram (CIT), putative antidepressant drugs, are very potent and selective 5-hydroxytryptamine (5-HT) uptake inhibitors in vitro. This study investigated the effects of these drugs and their desmethyl metabolites, Ro 12-5419 (desmethylcianopramine, cyan-desipramine) and desmethylcitalopram (DCIT), respectively, on the uptake of 5-HT and noradrenaline (NA) in vivo [protection against H 77/77 (4, alpha-dimethyl-metatyramine)-induced displacement of 5-HT and NA] and on related pharmacological activities. All the investigated drugs antagonized H 77/77-induced displacement of 5-HT in the rat brain, though the effects of the metabolites were considerably weaker than those of the parent compounds. The H 77/77-induced displacement of brain NA in rats and mice was antagonized only by Ro 12-5419 and Ro 11-2465. All the drugs potentiated the pressor response to 5-HT in pithed rats; however, Ro 12-5419 and particularly Ro 11-2465 could also block the response when used in higher doses (0.1 mg/kg). Only Ro 12-5419 and Ro 11-2465 were able to potentiate the pressor response to NA. Ro 12-5419 also potentiated thyrotropin releasing hormone (TRH) hyperthermia and antagonized reserpine hypothermia in mice; Ro 11-2465 potentiated the TRH hyperthermia only. CIT and DCIT were inactive in both these tests. Of all the four drugs only CIT and Ro 12-5419 considerably stimulated the hind limb flexor reflex in spinal rats. However, whereas the stimulatory effect of CIT was inhibited by the 5-HT antagonists metergoline and cyproheptadine, that of Ro 12-5419 was counteracted by the NA antagonist phenoxybenzamine only. Ro 11-2465, when used in low doses (ca. 1 mg/kg), slightly potentiated the flexor reflex, whereas in higher doses (4–16 mg/kg) it had no effect itself but antagonized the stimulatory action of the 5-HT agonists fenfluramine, quipazine and LSD. The results obtained indicate that Ro 11-2465 and CIT, as well as their desmethyl metabolites, are also potent 5-HT uptake inhibitors in vivo. However, only CIT and DCIT are concurrently devoid of effect on uptake of NA. In contrast, Ro 11-2465 and particularly Ro 12-5419 appear to also inhibit the uptake of NA. Moreover, Ro 11-2465 appears to block central and peripheral 5-HT receptors.The results were presented at the 14th CINP Congress, Florence, June 19–23, 1984     

Handling of biological samples in the determination of the anti-neoplastic drug mitomycin C

A study to ascertain suitable conditions for handling biological samples from patients, treated with the antibiotic mitomycin C (MMC), with the objective of improving the accuracy and reliability of the determination is described. Situations frequently occurring in medical practice are simulated to optimize procedures for reliable and reproducible sampling, sample treatment and determination of MMC. Continuation of drug partitioning in whole blood after sampling can be prevented by immediate cooling in ice before the separation of plasma from cells. The adjustment of the pH of urine samples is shown to be particularly important since a low urinary pH causes decomposition of MMC; moreover, it may decrease extraction recovery. Furthermore, long-term exposure of samples to daylight induces drug decomposition. Frozen storage of plasma and urine samples for periods greater than 3 weeks is to be avoided as this results in a considerable drop in MMC concentration. Repeated cycles of freezing and thawing are shown to have no effect upon the analytical results (6 cycles tested). The analysis of extracts of biological samples may take place up to at least 24 h after their preparation without measurable loss of analyte.     

Cervical tissue uptake of all-trans-retinoic acid delivered via a collagen sponge-cervical cap delivery device in patients with cervical dysplasia

The present study was undertaken to evaluate the systemic absorption and cervical tissue uptake of all-transretinoic acid (TRA), delivered via a collagen spongecervical cap delivery device in patients with intraepithelial cervical dysplasia. Ten patients with histologically proven mild or moderate cervical dysplasia were included in this pharmacologic study. The two TRA concentrations (0.05% and 0.372%) selected for study represent the starting and maximally tolerated doses used in phase I clinical trial. All-trans-retinoic-11-³H acid (³H-TRA, 500 Ci) was used to facilitate cervical tissue uptake studies. Cervical biopsies and post-treatment blood samples were obtained from each patient after TRA exposure. The uptake of TRA into cervical tissues four hours after drug administration was significantly increased at the maximally tolerated TRA dose. There was a rapid decrease in cervical tissue concentration of TRA at the 0.372% dose between 4 and 24 h after drug exposure, suggesting a relatively short elimination half-life of TRA in cervical tissues. HPLC analysis of post-treatment blood samples indicate that there was no systemic absorption of TRA after local cervical administration.     

In vitro stimulation by prostate extracts of rat ventral prostate stromal and epithelial cell division

We examined the effect of prostate cell extracts on the replication of highly enriched rat ventral prostate stromal and epithelial cells cultured in RPMI-1640. Extracts from normal rat prostates completely inhibited cell division in both fractions, while a 10% (v/v) extract of Dunning R-3327G adenocarcinoma inhibited replication of stromal cells but permitted that of epithelial cells. The cytotoxic effect of prostate extracts was dialyzable, heat stable, unaffected by proteases, soluble in acid/alcohol, and insoluble in chloroform. These properties are consistent with those of polyamines incubated in the presence of fetal calf serum. Dialyzed extracts from Dunning adenocarcinomas, and from human benign hypertrophic and carcinomatous prostates stimulated rat prostate stromal and epithelial cell division, in keeping with other reports of "growth factors" in prostate tissue. This mitogenic activity was stable to temperature (70 degrees C, 4 hours), and marginally if at all affected by exposure to trypsin or to pronase coupled to Sephadex. Short-term culture of separated prostate cells should provide a useful assay system for detecting putative autocrine or paracrine stromal and/or epithelial cell growth factors and identifying suspected homo- or heterotypic cellular interactions in normal and diseased prostates.