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A Jürgens

Publications and source records attributed to A Jürgens.

15 recordsLinked to original sources
PubMed2006

Nursery pollination by a moth in Silene latifolia: the role of odours in eliciting antennal and behavioural responses.

Since the 1970s it has been known that the nursery pollinator Hadena bicruris is attracted to the flowers of its most important host plant, Silene latifolia, by their scent. Here we identified important compounds for attraction of this noctuid moth. Gas chromatographic and electroantennographic methods were used to detect compounds eliciting signals in the antennae of the moth. Electrophysiologically active compounds were tested in wind-tunnel bioassays to foraging naïve moths, and the attractivity of these compounds was compared with that to the natural scent of whole S. latifolia flowers. The antennae of moths detected substances of several classes. Phenylacetaldehyde elicited the strongest signals in the antennae, but lilac aldehydes were the most attractive compounds in wind-tunnel bioassays and attracted 90% of the moths tested, as did the scent of single flowers. Our results show that the most common and abundant floral scent compounds in S. latifolia, lilac aldehydes, attracted most of the moths tested, indicating a specific adaptation of H. bicruris to its host plant.

Animals↗
PubMed2001

Oxidative modification of low-density lipoproteins and the outcome of renal allografts at 1 1/2 years.

BACKGROUND: Previous studies reported a significant association between hyperlipidemia of the recipient and chronic allograft nephropathy (CAN). However, the nature and the pathogenic mechanism of circulating lipid abnormalities in CAN remain unclear. METHODS: In a prospective study of 50 consecutive adult recipients of a cadaveric renal allograft, we investigated the impact of lipid abnormalities on the outcome of the graft at 1 1/2 years. Besides morphometric analysis of implantation and protocol biopsies, clinical and biochemical variables were studied at three-month intervals. Plasma concentrations of oxidized low-density lipoprotein (OxLDL) were determined by means of enzyme-linked immunosorbent assay. Immunohistochemical staining for OxLDL and macrophages was performed on paired renal biopsies. Study end points were the fractional interstitial volume and the 24-hour creatinine clearance at 11/2 years. RESULTS: High-density lipoprotein (HDL) cholesterol of the recipient < or =47 mg/dL was a risk factor for the functional (RR = 1.56; 95% CI, 0.978 to 2.497) and the morphological (RR = 2.75; 95% CI, 1.075 to 7.037) outcome of the graft, mainly in patients without acute rejection (RR = 2.03; 95% CI, 1.13 to 3.65, and RR = 4.67; 95% CI, 1.172 to 18.582, respectively). Interstitial accumulation of OxLDL was inversely associated with HDL cholesterol (R = -0.476, P = 0.019), and was associated with a higher density of tubulointerstitial macrophages (R = 0.656, P = 0.001) and a higher fractional interstitial volume at 11/2 years (P = 0.049). CONCLUSION: Decreased HDL cholesterol levels of the recipient adversely affect the outcome of renal allografts through the accumulation of OxLDL in the renal interstitium of the graft. Interstitial accumulation of OxLDL was associated with the presence of macrophages and the development of interstitial fibrosis.

Adult↗
PubMed2000

Fibrous intimal thickening at implantation as a risk factor for the outcome of cadaveric renal allografts.

BACKGROUND: During the past decade, the donor age of cadaveric renal allografts steadily increased. Because cerebrovascular injury is the main cause of death in this donor population, an increased prevalence of atherosclerotic lesions in the retrieved grafts could be anticipated. In a prospective study, we investigated the predictive value of morphologic lesions at implantation for the functional and morphologic outcome of cadaveric renal allografts at 1 1/2 years. METHODS: In 50 consecutive adult recipients of a cadaveric renal allograft, under cyclosporine-based regimen, implantation biopsies and subsequent protocol biopsies at 18 months were performed, and morphometrically analyzed for the extent of glomerulosclerosis, interstitial fibrosis, and atherosclerosis. Risk factors were assessed at implantation and during the subsequent observation period of 18 months. Endpoints for this study were: the 24-hr creatinine clearance (normalized for body surface area) and the fractional interstitial volume at 1 1/2 years. RESULTS: In multivariate analysis, fibrous intimal thickening at implantation (FIT) was the main determinant of the functional and morphologic outcome at 1 1/2 years. FIT represented a relative risk of 4.55 for interstitial fibrosis (95% CI=1.855-11.138), and 1.89 for impaired renal function (95% CI=1.185-3.007) at 1 1/2 years. FIT adversely affected fractional interstitial volume at 1 1/2 years (34.3 vs. 27.7%, P=0.004), as well as renal function (54 vs. 68 ml/min/1.73 m2, P=0.028). CONCLUSIONS: Fibrous intimal thickening at implantation is a determinant risk factor for the functional and morphologic outcome of cadaveric renal allografts at 1 1/2 years.

Adult↗
PubMed2000

Floral scent compounds of Amazonian Annonaceae species pollinated by small beetles and thrips.

Chemical analysis (GC-MS) yielded a total of 58 volatile compounds in the floral scents of six species of Annonaceae distributed in four genera (Xylopia, Anaxagorea, Duguetia, and Rollinia), Xylopia aromatica is pollinated principally by Thysanoptera and secondarily by small beetles (Nitidulidae and Staphylinidae), whereas the five other species were pollinated by Nitidulidae and Staphylinidae only. Although the six Annonaceae species attract a similar array of pollinator groups, the major constituents of their floral scents are of different biochemical origin. The fragrances of flowers of Anaxagorea brevipes and Anaxagorea dolichocarpa were dominated by esters of aliphatic acids (ethyl 2-methylbutanoate, ethyl 3-methylbutanoate), which were not detected in the other species. Monoterpenes (limonene, p-cymene, alpha-pinene) were the main scent compounds of Duguetia asterotricha, and naphthalene prevailed in the scent of Rollinia insignis flowers. The odors of X. aromatica and Xylopia benthamii flowers were dominated by high amounts of benzenoids (methylbenzoate, 2-phenylethyl alcohol).

Animals↗
PubMed2000

["Refuse hoarding syndrome"].

OBJECTIVE: The "litter hoarding syndrome" is described only occasionally during the past decades. It seems to be rather unknown in the psychiatric literature. In the course of the syndrome the patients gather more and more litter in their homes until it becomes unhabitable. Physicians and social psychiatric services are often confronted with this manifestation of a psychiatric illness. METHODS: Because of the dramatic development, the extent and the specific circumstances this paper reports case of a young female patient with the litter hoarding syndrome. RESULTS: The term "litter hoarding syndrome" was first coined by Dettmering [3] during a lecture on 25.1.1984 in the Psychiatric Clinic of the Eppendorf University Hospital in Hamburg. In 1985 Klosterkötter et al. [7] described the "diogenes syndrome" which offered some nosological similarities. With the exception of this publications an the PhD thesis by Pastenaci [11] only a few reports have been published during the last 28 years throughout the world and no epidemiological data about the syndrome can be found. CONCLUSION: Based on this case some ideas about differential diagnosis and syndrome classification shall be presented.

Adult↗
PubMed1999

[Study of the correspondence between pure tone and distorsion product otoacoustic emissions audiometrics: basis for an objective cochlear audiometrics model].

The correspondence between distortion product otoacoustic emissions (DPOAE intensities) and pure tone threshold audiometrics (PTTA) was studied. In 140 human ears with normal hearing or cochlear hearing loss, PTTA and DPOAE were recorded at 70 dB SPL (L70dpgram). The results served to develop a mathematical model for predicting PTTA from DPOAE. It was easily concluded that several DPOAE measures are needed to obtain reliable predictions of PTTA. In our simple model, four PTTA variables (PTTA at the frequencies of 500 Hz and 1, 2 and 4 kHz) can be predicted from a six-point L70dpgram (resolution of 2 points per octave) with reasonable accuracy. This model predicts not only numerical values, but also the diagnosis of degree of hearing loss with a high sensitivity and specificity (around 90%). It is the first clinically useful model of objective audiometrics to be published. In contrast, the L75 dpgram performed poorly in predicting PTTA and hearing loss categories.

Acoustic Stimulation↗
PubMed1994

Small cell carcinoma of the larynx: results of therapy.

Small cell carcinoma is a rare malignant tumor of the larynx. Since this lesion was first described, only 58 cases have been reported in the literature. Between December 1985 and March 1992, five patients with small cell carcinoma of the larynx were treated at the Hospital de la Santa Creu i Sant Pau in Barcelona, Spain. One patient was treated with radiation therapy alone, three patients with chemotherapy and radiation therapy, and one patient with surgery, chemotherapy and radiation therapy. Local and distant control was achieved in only one patient who was observed for 12 months after radiation therapy. Four patients died, one of local disease without distant metastasis at 6 months following treatment, one of local and distant disease at 53 months after radiation therapy, and two of distant metastasis without local disease at 22 and 36 months following treatment. In spite of the fact that only one of the five patients presented in this series is alive and free of disease 12 months following treatment, recent published information suggests that chemotherapy and radiotherapy are currently the most effective form of therapy for small cell carcinoma of the larynx.

Aged↗
PubMed1993

Oestrogen receptor occurrence in the male mouse brain: modulation by paternal experience.

Paternal behaviour (pup-searching and retrieving of pups) was studied in male house mice with different experience in pup care and oestrogen receptor immunoreactive (ER-IR) cells were localized and quantified in their brains. Experience with pups induced paternal behaviour and correlated with (a) the occurrence of ER-IR cells in the bed nucleus of the stria terminalis, hippocampus, subiculum, lateral septal nuclei, entorhinal and piriform cortex, (b) increased numbers of ER-IR cells in the medial preoptic area and arcuate nucleus of the hypothalamus, and (c) decreased presence of ER-IR cells in the periventricular grey of the midbrain. The data indicate oestrogen receptor modulation in the male brain and suggest that oestrogen binding in distinct brain areas is involved in the regulation of paternal behaviour.

Animals↗
PubMedDate not supplied

[Solitary naso-sinusal fibrous tumor].

Here we present two clinical cases of solitary naso-sinusal fibrous tumour. This tumour has a mesenchymal origin and has an evident pleural location, with well defined immunohistochemical and ultrastructural characteristics. The clinical manifestation is an apparent benign tumour with an inclination to local aggressiveness. The most effective treatment seems to be surgical removal, but given the low number of cases mentioned (there are only eight cases reported in international literature), and the tendency to eventual recurrence, called for cobalt therapy after surgery. The evolution of clinical cases is irregular.

Aged↗
PubMedDate not supplied

[Laryngeal amyloidosis: treatment vs. abstention].

Four cases of laryngeal amyloidosis diagnosed between 1986 and 1992 are reported. Two cases had supraglottic localization and the remaining two involved both glottis and subglottis. CT was performed in all cases. Diagnosis was made in the four cases by biopsy. All of them were classified as localized laryngeal amyloidosis after doing immunoelectrophoretic study in blood and urine, and rectal biopsy in two cases. Surgical excision by carbon dioxide laser was performed in one patient, while in the remaining three patients, a preservative attitude was taken. Results of both attitudes are presented, as well as a literature review on the topic.

Adult↗