[Research with participants suffering from dementia. Ethical and legal considerations in research involving human subjects]. / Forschung mit demenzkranken Probanden. Zum forschungsethischen und rechtlichen Umgang mit diesen Personen.

Using case reports from the health services research project Action Alliance Pain-Free City Muenster, fundamental issues of research ethics, data protection and legal guardianship are shown and explained. A plan of important aspects to be considered while planning, conducting and recruiting for research with nursing home inhabitants suffering from dementia in a legally correct and safe manner is presented.

Involvement of NF-Y and Sp1 in basal and cAMP-stimulated transcriptional activation of the tryptophan hydroxylase (TPH ) gene in the pineal gland.

The expression of the tryptophan hydroxylase (TPH) gene, encoding the rate-limiting enzyme of serotonin biosynthesis, is tightly regulated both at the transcriptional and at the post-transcriptional levels. In the pineal gland, transcription of the gene is activated in response to an intracellular circadian increase of the cAMP concentration. We have previously shown that transcription of a 2.1-kb fragment of the human TPH promoter is induced by cAMP, although it lacks the canonical cAMP responsive element, CRE. The minimal promoter (-73/+29) has only weak transcriptional activity but is responsive to cAMP. It contains an inverted CCAAT box, which was demonstrated to be involved in this response. Here, we have extended our investigation to the functional features of the inverted CCAAT box in the -252/+29 TPH promoter, which has a higher basal activity. We show that an additional cis -acting sequence, the adjacent GC-rich region, cooperates with the inverted CCAAT box for the full activation of basal transcription, and that both elements are essential for the full cAMP response. We also show that in pinealocytes, NF-Y and Sp1 transactivators bind the inverted CCAAT box and GC-rich-region, respectively. These factors participate in a novel pathway for the cAMP-mediated response of the TPH promoter, which is independent of the canonical CRE-mediated response.

Design and serendipity in establishing a large cohort with wide dietary intake distributions : the National Institutes of Health-American Association of Retired Persons Diet and Health Study.

In 1995-1996, the authors mailed a food frequency questionnaire to 3.5 million American Association of Retired Persons members who were aged 50-69 years and who resided in one of six states or two metropolitan areas with high-quality cancer registries. In establishing a cohort of 567,169 persons (340,148 men and 227,021 women), the authors were fortunate in that a less-than-anticipated baseline response rate (threatening inadequate numbers of respondents in the intake extremes) was offset by both a shifting and a widening of the intake distributions among those who provided satisfactory data. Reported median intakes for the first and fifth intake quintiles, respectively, were 20.4 and 40.1 (men) and 20.1 and 40.0 (women) percent calories from fat, 10.3 and 32.0 (men) and 8.7 and 28.7 (women) g per day of dietary fiber, 3.1 and 11.6 (men) and 2.8 and 11.3 (women) servings per day of fruits and vegetables, and 20.7 and 156.8 (men) and 10.5 and 97.0 (women) g per day of red meat. After 5 years of follow-up, the cohort is expected to yield nearly 4,000 breast cancers, more than 10,000 prostate cancers, more than 4,000 colorectal cancers, and more than 900 pancreatic cancers. The large size and wide intake range of the cohort will provide ample power for examining a number of important diet and cancer hypotheses.

In vivo neutralization of endogenous brain fractalkine increases hippocampal TNFalpha and 8-isoprostane production induced by intracerebroventricular injection of LPS.

Fractalkine is a chemokine widely and constitutively expressed in the brain and, as suggested by in vitro studies, it is involved in brain inflammatory responses. In this study, we have investigated the in vivo anti-inflammatory potential of fractalkine in a model of neuroinflammation induced by intracerebroventricular injection of lipopolysaccharide (LPS) in rats. LPS induces a rapid and acute production of the pro-inflammatory cytokine, TNFalpha, in hippocampus and cerebrospinal fluid (CSF), and an increase of 8-isoprostane levels, a marker of oxidative stress, in hippocampus. Although intracerebroventricular injection of fractalkine has no effect on TNFalpha and 8-isoprostane production, neutralization of endogenous fractalkine within the brain with a specific anti-fractalkine antibody potentiates LPS effects. These data emphasize the involvement of constitutive brain fractalkine in the control of inflammatory reaction in CNS.

Sources of elevated serum androgens in postmenopausal women who develop breast cancer.

Postmenopausal women with elevated serum androgens are at an increased risk of breast cancer. High dehydroepiandrosterone sulfate concentrations in these women suggest increased adrenal secretion. Both the adrenals and ovaries could contribute to elevated concentrations of androstenedione (Delta4A). 11beta-Hydroxyandrostenedione (11betaOHA) is elevated, and the Delta4A:11betaOHA ratio is depressed when the adrenals are the primary source of elevated Delta4A in women. Conversely, Delta4A:11betaOHA is elevated when the ovaries are the primary source. We prospectively evaluated associations of serum 11betaOHA and Delta4A:11betaOHA with breast cancer in the Columbia, Missouri Serum Bank to identify the source of elevated Delta4A related to risk. Fifty-three postmenopausal women who were not taking estrogens when they donated blood and were diagnosed with breast cancer up to 10 years later (median, 2.9 years) served as cases. Two controls, who were also postmenopausal and not taking estrogens, were matched to each case on age, date, and time of blood collection. Serum Delta4A concentration was significantly (trend P = 0.02) positively associated with breast cancer risk. Adjusted risk ratios for women in the lowest to highest tertiles were 1.0, 1.6, and 2.4 [95% confidence interval (CI), 0.9-6.5]. However, neither 11betaOHA concentration nor Delta4A:11betaOHA was related to risk. Comparable risk ratios were 1.0, 1.2, and 1.4 (95% CI, 0.5-3.6) for 11betaOHA and 1.0, 1.2, and 1.2 (95% CI, 0.4-3.5) for Delta4A:11betaOHA. Our results suggest that neither the ovaries nor adrenals are the predominant source of elevated serum Delta4A in postmenopausal women who develop breast cancer, but rather both may contribute.

Role of transurethral resection of the prostate in population-based prostate cancer incidence rates.

The extensive pool of asymptomatic prostate disease in the population, which increases substantially with age, suggests that the frequent use of transurethral resection of the prostate (TURP) in recent decades has had a large effect on prostate cancer incidence. The authors identified the effect of TURP-detected prostate cancer on the observed incidence rates between 1973 and 1993 for men aged 65 years and older. They linked population-based cancer registry data from the Surveillance, Epidemiology, and End Results Program to Medicare records between 1986 and 1993 to determine whether a TURP occurred sufficiently close to the time of a prostate cancer diagnosis for them to assume that it led to the diagnosis. TURP-detected cases prior to 1986 were calculated using an indirect method that involved multiplying the TURP procedure rate in the general population (from the National Hospital Discharge Survey) by estimates of the proportion of TURPs resulting in a prostate cancer diagnosis (from Medicare data and the literature). TURP explained much of the observed increase in overall prostate cancer incidence between 1973 and 1986 and possibly all of it in men aged 70 years and older. However, its influence on the trend and overall magnitude of the rates diminished between 1987 and 1993. The changing role of TURP in detecting prostate cancer is attributed to changes in medical technology and screening practices. The declining influence of TURP on prostate cancer incidence is likely to have continued beyond the study period due to the recent introduction and increasing use of medications for treating obstructive uropathy.

Serum organochlorine pesticides and PCBs and breast cancer risk: results from a prospective analysis (USA).

OBJECTIVE: To prospectively evaluate relationships of organochlorine pesticides and polychlorinated biphenyls (PCBs) with breast cancer, we conducted a case-control study nested in a cohort using the Columbia, Missouri Breast Cancer Serum Bank. METHODS: Women donated blood in 1977-87, and during up to 9.5 years follow-up, 105 donors who met the inclusion criteria for the current study were diagnosed with breast cancer. For each case, two controls matched on age and date of blood collection were selected. Five DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] analogs, 13 other organochlorine pesticides, and 27 PCBs were measured in serum. RESULTS: Women in the upper three quartiles of hexachlorobenzene were at twice the risk of breast cancer compared to those in the lowest quartile. However, there was no evidence for a dose-response relationship, and the association was limited to women whose blood was collected close to the time of diagnosis. Women with higher serum levels of other organochlorine pesticides and PCBs showed no increased risk of breast cancer overall, although positive associations were suggested for PCB-118 and PCB-138 when blood was collected close to the time of diagnosis. CONCLUSIONS: Results of this study do not support a role for organochlorine pesticides and PCBs in breast cancer etiology.

Relationships of serum carotenoids, retinol, alpha-tocopherol, and selenium with breast cancer risk: results from a prospective study in Columbia, Missouri (United States)

To evaluate relationships of serum carotenoids, alpha-tocopherol, selenium, and retinol with breast cancer prospectively, we conducted a case-control study nested in a cohort from the Breast Cancer Serum Bank in Columbia, Missouri (United States). Women free of cancer donated blood to this bank in 1977-87. During up to 9.5 years of follow-up (median = 2.7 years), 105 cases of histologically confirmed breast cancer were diagnosed. For each case, two women alive and free of cancer at the age of the case's diagnosis and matched on age and date of blood collection were selected as controls. A nonsignificant gradient of decreasing risk of breast cancer with increasing serum beta-cryptoxanthin was apparent for all women. Serum lycopene also was associated inversely with risk, and among women who donated blood at least two years before diagnosis, a significant gradient of decreasing breast cancer risk with increasing lycopene concentration was evident. A marginally significant gradient of decreasing risk with increasing serum lutein/zeaxanthin also was apparent among these women. We did not observe any evidence for protective effects of alpha- and beta-carotene, alpha-tocopherol, retinol, or selenium for breast cancer. Results of this study suggest that the carotenoids beta-cryptoxanthin, lycopene, and lutein/zeaxanthin may protect against breast cancer.

[Paracrine regulation of anterior pituitary hormones by neuropeptides]. / Régulation paracrine des hormones antéhypophysaires par les neuropeptides.

The hypothalamus is the source of neuropeptides which, being secreted into the portal system, control the synthesis and the secretion of the anterior pituitary hormones. Besides the well characterized hypothalamic central control and the hormonal peripheral control, recent studies have shown, in the anterior pituitary, the expression, among many other regulatory factors, of neuropeptides that are identical to those produced by the hypothalamus and that seem involved in the local control of anterior pituitary functions through autocrine or paracrine mechanisms. The presence of the neuropeptide mRNAs, precursors and mature forms of the peptides in anterior pituitary tissues as well as the secretion of the mature peptides argue in favor of the intrinsic ability of the normal and tumoral anterior pituitary to express neuropeptides. This expression of neuropeptides occurring in tissues bearing functional receptors for these ligands, anterior pituitary control could rely, at least in part, on endogenous neuropeptides acting locally. Correlations between neuropeptide contents in the anterior pituitary and the plasma levels of anterior pituitary hormones suggest that neuropeptides of anterior pituitary origin can play a local regulatory role, complementary of the classical hypothalamic central control. In the normal anterior pituitary which remains under hypothalamic control, it is presently difficult to evaluate the relative importance of the local and central control. However, anterior pituitary hyperplasia and pituitary tumors represent two models in which the specific contribution of the local control is easier to define.

Evidence of thyrotropin-releasing hormone (TRH) gene expression in rat anterior pituitaries and modulation by estrogens of TRH-like immunoreactivity and TRH-elongated peptide contents.

TRH gene expression in the anterior pituitary has previously been reported in the human in vivo and in the rat in vitro. Until now, modulation of this synthesis with glucocorticoids and thyroid hormones has been observed in rats. The present study demonstrates for the first time that the TRH gene is also expressed, in vivo, in the rat anterior pituitary and that anterior pituitary TRH-like immunoreactivity (TRH-LI) and elongated forms of the immediate TRH progenitor sequence (TRH-elongated peptide) contents are also modulated by estrogens (E2). To investigate the presence of proTRH mRNA in the rat anterior pituitary, total RNA was reverse transcribed (RT) and the RT products were then amplified by PCR. Treatments with E2 were performed on intact and ovariectomized (OVX) rats for 2 months. TRH-LI was measured by RIA with an antibody which did not recognize the TRH-like peptide. pGlu-Glu-Pro-NH2 (< EEP-NH2) (cross-reactivity < 0.1%) and was characterized further as TRH-LI by HPLC. TRH-elongated peptides were measured by EIA and characterized by Sephadex G-50 chromatography and immunoblotting (molecular mass 25-35 kDa). The plasma prolactin levels and the pituitary sizes were increased by E2 treatment in both intact and OVX rats. Anterior pituitary TRH-LI increased in intact E2-treated rats compared with intact rats (82.7 +/- 19.0 versus 39.6 +/- 3.6 fmol/mg protein; means +/- S.E.M.; P < 0.001). This increase was greater when E2 was administered to OVX rats (599.0 +/- 98.4 after E2 treatment versus 58.6 +/- 3.6 fmol/mg protein: P < 0.001). In intact rats, anterior pituitary TRH-elongated peptide contents were not modified by E2 treatment while they were significantly decreased in OVX E2-treated rats (144.6 +/- 8.8 versus 223.7 +/- 9.5 fmol/mg protein; P < 0.001). These results demonstrate TRH gene expression in the rat anterior pituitary in vivo and suggest that E2 treatment is responsible for an increase in anterior pituitary TRH-LI, together with a decrease in TRH-elongated peptide contents.

[Physiology of the anterior pituary gland]. / Physiologie de l'antéhypophyse.

The anterior pituitary is a complex gland which controls the various peripheral endocrine glands (thyroid, adrenal cortex, ovary and testis) as well as essential functions as growth, reproduction and lactation. Its physiological role is of paramount importance and its pathology multiple, including functional dysregulations and diseases caused by lesions or tumors, in particular pituitary adenomas. Recent data show that, in addition to the classical control of anterior pituitary hormones by hypothalamic neuropeptides and by peripheral hormones, local controls of the paracrine or autocrine type exist. Although these new findings seem to increase the complexity of anterior pituirary control, they might, in the future, shed further light on the physiopathology of this gland.

Multiple tyrosine hydroxylase transcripts and immunoreactive forms in the rat: differential expression in the anterior pituitary and adrenal gland.

Several regulatory neurofactors, classically associated with the hypothalamus, may be synthesized in the anterior pituitary (AP). Dopamine (DA) is the main prolactin-inhibiting factor. Its de novo synthesis in the normal AP has not been proved, although the TH transcript has been previously demonstrated by RT/PCR in the AP. We investigated tyrosine hydroxylase (TH) gene expression at both the protein and mRNA levels in the AP of normal random cycling female rats and in a catecholaminergic tissue, the adrenal gland (AG). The Western blot analysis of AP homogenates revealed two immunoreactive forms of TH in the AP, both differing from the TH present in the AG. RT/PCR products from AP and AG mRNA were subcloned and sequenced. In addition to the full-length form, we identified two TH transcripts generated by alternative splicing either involving the use of a new alternate splice-donor site within exon 2 or skipping exon 11. The form lacking exon 11 was not isolated from the AG. In the AP, all three forms were present. Although the AP contained the full-length TH mRNA, the expected size protein was not detected. Thus, there is alternative splicing of the TH primary transcript, and putative additional post-translational regulation may yield TH proteins with no enzymatic activity, at least in non-catecholaminergic tissues.

Tyrosine-hydroxylase immunoreactive fibres in the rat anterior pituitary.

Tyrosine-hydroxylase (TH)-like immunoreactivity was investigated in normal and oestrogenized rat anterior pituitaries in the light of recent studies showing a TH enzymatic activity in the gland and the presence of TH mRNA in endocrine cells. Sparse TH positive fibres, probably dopaminergic as assessed by the absence of dopamine-beta-hydroxylase (DBH) immunoreactivity, were detected in the anterior pituitary, but the detection of TH immunoreactivity in cells was unsuccessful.

Effect of the slow-release formulation of somatuline (BIM 23014) on estrogen-induced hyperprolactinemia and lactotroph hyperplasia in the female rat.

Somatuline, in common with other SRIH analogues, exerts antiproliferative and antisecretory activities on various tumors. Our purpose was to test the effectiveness of a slow-release formulation of somatuline on lactotroph hyperplasia and PRL hypersecretion induced by estrogens (17 beta E2) in rats. Female rats were primed with 17 beta E2 for 6 weeks before receiving somatuline (2 mg/kg) intramuscular injections every 10 days for one month. The mean anterior pituitary weight was 11.22 +/- 0.32 mg (mean +/- SEM) in non-estrogenized rats, 29.62 +/- 1.63 mg in 17 beta E2-primed rats and 23.58 +/- 1.26 mg in 17 beta E2-primed somatuline-treated rats. Mean plasma PRL level was 5.63 +/- 0.97 ng/ml, 182.37 +/- 27.55 ng/ml and 113.89 +/- 15.07 ng/ml in the same groups respectively. Thus, the 17 beta E2-induced pituitary enlargement and hyperprolactinemia were 20% and 38% lower respectively when animals were treated with somatuline during the last month of estrogenization. The 17 beta E2-induced increase in PRL cell density was also reduced by somatuline treatment. We conclude that the slow-release formulation of somatuline impedes 17 beta E2-induced hyperprolactinemia and pituitary enlargement concomittantly, at least in part by acting on lactotroph proliferation.

Evidence of tyrosine hydroxylase mRNA in the anterior and neurointermediate lobes of female rat pituitary.

The anterior pituitary is thought to be unable to synthesize dopamine (DA) except under experimental conditions where a tyrosine hydroxylase (TH) activity, the rate-limiting step of its synthesis, has been demonstrated. In this work, we tested whether the enzyme described as active under particular conditions comes from de novo TH gene transcription or from a pre-existing TH mRNA poorly translated or untranslated under physiological conditions. Therefore, we searched for the presence of TH mRNA in normal female rat pituitary using the polymerase chain reaction following reverse transcription (RT/PCR) and in situ hybridization (ISH). The neurointermediate lobe (NIL) of the hypophysis was used as negative tissue, since it is thought to be unable to synthesize TH. As expected, no ISH labelling could be seen in the neural lobe (NL). However, scarce labelled cells were found in the intermediate lobe (IL) confirming the positive results observed in the NIL by RT/PCR. The anterior lobe (AL) also presented TH mRNA by PCR and ISH. The TH gene expression in sparse cells of the AL is discussed in regard to the ability of the AL to synthesize DA under particular conditions from a pre-existing mRNA.

Assessment of stimuli controlling the requests of students with severe mental retardation during a snack routine.

This study assessed stimuli controlling requests during a snack routine after extensive request training with a delayed prompt procedure. During training sessions, one of three three-item snack groups was presented to 3 subjects with severe mental retardation. Assessment sessions involved (a) training conditions (all items were visible), (b) presenting two of three items from a particular group, or (c) presenting no items. One subject requested food items when no food items were present, 2 frequently requested a missing item when the two other items were visible, and all subjects requested visible items. Procedures for assessing stimulus control, such as those described in the current paper, should lead to a better understanding of the variables controlling behaviors that initially appear perplexing and unpredictable.