Publications by authors named "Lehr P"

Adaptation of crops to recurrent drought stress is crucial for maintaining agricultural productivity and achieving food security under changing climate. Guard cells, pivotal regulators of plant water usage and assimilation, are central to this adaptation process. However, the metabolic dynamics of guard cells under drought stress remain poorly understood, particularly in grapevine, a prominent crop grown in arid regions, and maize, a staple crop with substantial water requirements.

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Human interleukin-1β (IL-1β) is a pro-inflammatory cytokine that plays a critical role in the regulation of the immune response and the development of various inflammatory diseases. In this publication, we disclose our efforts toward the discovery of IL-1β binders that interfere with IL-1β signaling. To this end, several technologies were used in parallel, including fragment-based screening (FBS), DNA-encoded library (DEL) technology, peptide discovery platform (PDP), and virtual screening.

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Human interleukin-1β (hIL-1β) is a pro-inflammatory cytokine involved in many diseases. While hIL-1β directed antibodies have shown clinical benefit, an orally available low-molecular weight antagonist is still elusive, limiting the applications of hIL-1β-directed therapies. Here we describe the discovery of a low-molecular weight hIL-1β antagonist that blocks the interaction with the IL-1R1 receptor.

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Training systems are an option to handle the pronounced apical dominance of grapevines and to influence diverse traits of the corresponding wine. However, it is still unclear if different training systems generate signatures in the metabolome of the wine. By an untargeted metabolomics approach using (SPME) GC-MS wine (volatiles) and leaves were evaluated.

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Lipoprotein lipase (LPL) plays a central role in triglyceride (TG) metabolism. By catalyzing the hydrolysis of TGs present in TG-rich lipoproteins (TRLs), LPL facilitates TG utilization and regulates circulating TG and TRL concentrations. Until very recently, structural information for LPL was limited to homology models, presumably due to the propensity of LPL to unfold and aggregate.

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Steroid sulfatase (STS) is an attractive target for a range of oestrogen- and androgen-dependent diseases. In search of novel chemotypes of STS inhibitors, we had previously identified nortropinyl-arylsulfonylureas 1; however, while these compounds were good inhibitors of purified STS (lowest K(i)=76 nM), they showed only weak inhibition of STS activity in cells (lowest IC(50) around 2 microM). Extended structure-activity relationship studies involving modification of the phenylacetyl side chain and replacement of the nortropine element by simpler scaffolds led to the discovery of N-acyl arylsulfonamides, more specifically N-(Boc-piperidine-4-carbonyl)-benzenesulfonamides, as STS inhibitors, some of which exhibit improved cellular potency (best IC(50)=270 nM).

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Steroid sulfatase (STS) has emerged as an attractive target for a range of estrogen- and androgen-dependent diseases. Searching for novel chemotypes as STS inhibitors, we identified nortropinyl-arylsulfonylurea 3 as a hit from high-throughput screening. A series of analogues was prepared in order to explore the essential structural elements for STS inhibition, and first structure-activity relationships were established.

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Steroid sulfatase (STS) has emerged as a highly attractive target for the therapy of a number of disorders. Starting with the known inhibitor estrone sulfamate (1) as lead compound and with the finding that steroid sulfamates containing a nonaromatic A-ring are inactive, chromen-4-one sulfamates were designed, prepared, and tested for their ability to block human STS. This new class of nonsteroidal inhibitors shows high potency when the sulfamate group and the side chain are situated in diagonally opposite positions (i.

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Steroid sulfatase (STS) regulates the formation of active steroids from systemic precursors, such as estrone sulfate and dehydroepiandrosterone sulfate (DHEAS). In breast tissues, this pathway is a source for local production of estrogens, which support the growth of endocrine-dependent tumours. Therefore, inhibitors of STS could have therapeutic potential.

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We wished to explore the relationships between waking HMPAO uptake and visually scored polysomnography. We hypothesized that HMPAO activity would correlate positively with slow wave sleep measures the same night. Eight unmedicated unipolar patients with current DSM-IV major depression (17-item Hamilton Depression Rating Scale score 21.

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Considering the concept that depressive disorders were not only resulting from activity of one neurotransmitter, possible interactions between the noradrenergic system and a selective serotonin uptake inhibitor, fluoxetine, were investigated in order to test the hypothesis of noradrenergic or serotonergic involvement in depression. So the biological parameters (plasma and urinary MHPG, platelet serotonin) were evaluated by HPLC. The aim of this study was to evaluate the correlations between the concentrations of MHPG and serotonin in 32 melancholic patients treated by fluoxetine (20 mg/day) during a minimum of three weeks.

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The effects of intraperitoneal administration of fluoxetine (2.5, 5, 10 or 20 mg kg(-1)) and norfluoxetine (10 mg kg(-1)) on 5-hydroxytryptamine (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) metabolism were examined in the blood platelets and brain of rats killed 3 h after a single dose. Several experiments were performed to evaluate the effect of norfluoxetine.

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Male rats were treated daily with an intraperitoneal injection of 15 mg aluminum (Al chloride)/kg body weight for 17 d, in order to study the effects on superoxide dismutase (SOD) activities in the brain (cortex). No significant difference between control and treated animals was registered in the Cu/Zn and Mn SOD activities in the gray matter of the cortex. High Al levels were found in the plasma, the spleen, and the liver of the treated animals in comparison to the controls, but not in the cortex homogenates (gray matter).

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The aim of this clinical study was to investigate 32 melancholic patients treated by fluoxetine (20 mg/day). The clinical examination to evaluate the antidepressant effect of fluoxetine was realized by using the HDS/MES criteria. The patients were divided into three groups (responders, partial responders with or without a relapse, non responders) according to their clinical evolution during treatment.

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Functional brain imaging techniques are being used increasingly to infer disturbances in brain function in various neuropsychiatric disorders, but the specificity of such findings is not always clear. We retrospectively examined the effects of one possible confound - cigarette smoking - on cortical uptake of iodine-123 iodoamphetamine (IMP) using single-photon emission tomographic imaging in a young (mean age=35 years) healthy group of male controls divided according to their smoking history. Subjects who had never smoked (n=17), or those with a history of smoking but no recent smoking (n=8), had equivalent and significantly higher mean cortical uptake of IMP than subjects with a history of smoking and who were current smokers (n=8).

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Ten long-term abstinent alcoholics (mean abstinence = 7.7 years) were compared with 13 recently detoxified substance-dependent inpatients (mean abstinence = 25 days) and 8 nonalcoholic control subjects on global end regional measures of cortical cerebral blood flow (CBF), and on neuropsychological measures. CBF was assessed using 123iodoamphetamine (IMP) single photon emission computed tomography (SPECT) under conditions of behavioral challenge (Raven's Progressive Matrices).

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Normal and uremic adult male rats were given a daily ip injection of 20 mg Al (Al chloride)/kg for 14 d. The results indicate that Al induces a significant decrease in food ingestion, weight gain, and total protein concentration in the plasma. Compared with control animals, very high increases in Al levels were found in plasma and hepatic homogenates (about 36 and 19 times, respectively).

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Systematic modifications of HIV protease inhibitor (2R,3S,4S)-4-[[(benzyloxycarbonyl)-L-valyl]-amino]-3-hydroxy-2-[(4- methoxybenzyl)amino]-5-phenylpentanoyl)-L-valine 2-(aminomethyl)- benzimidazole amide led to a novel series of inhibitors with shortened, modified carboxy terminus. Their synthesis, in vitro enzyme inhibitory data, and antiviral activities are reported. Of particular interest are derivatives featuring the (1S,2R)-1-amino-2-hydroxyindan moiety at the P2'-position since some of them exhibit substantial oral bioavailability in mice.

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Young rats were treated by gastric intubation with aluminum chloride (100 mg Al/kg/day) and aluminum lactate (100 and 200 mg Al/kg/day) from postnatal days 5 to 14. This treatment lead to a reduction in body weight. The plasma concentrations of total proteins and albumin decreased whereas the alpha 1 globulins increased in the treated rats.

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A series of inhibitors of human immunodeficiency virus type 1 (HIV-1) proteinase containing the 2-aralkyl-amino-substituted statine moiety as a novel transition-state analog was synthesized, with the aim to obtain compounds which combine anti-HIV potency with oral bioavailability. The reduced-size 2-aminobenzylstatine derivative SDZ PRI 053, which contains 2-(S)-amino-3-(R)-hydroxyindane in place of an amino acid amide, is a potent and orally bioavailable inhibitor of HIV-1 replication. The antiviral activity of SDZ PRI 053 was demonstrated in various cell lines, in primary lymphocytes, and in primary monocytes, against laboratory strains as well as clinical HIV-1 isolates (50% effective dose = 0.

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The aim of this study was to develop an analytical method for free and conjugated 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) in urine. After hydrolysis of the conjugated forms, the urinary MHPG was purified by solid-phase extraction on anion exchanger and eluted with a water-methanol (1:1, v/v) mixture. After addition of ethyl acetate to the eluate and back-extraction into acetic acid, the aqueous phase was separated on a C18 column by HPLC and detected amperometrically.

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Derivation of the 2-aminobenzylstatine containing HIV-1 proteinase (PR) inhibitor I led to a series of compounds with considerably improved antiviral activity, the most potent derivatives inhibiting HIV-1 with IC50 values below 25 nM. This was achieved by the combination of several structural modifications, most prominently by introduction of a benzimidazole heterocycle into the inhibitor. The mode of action of the 2-aminobenzylstatine PR inhibitors was demonstrated to be inhibition of gag precursor processing.

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A convenient procedure for the synthesis of 2-heterosubstituted statine derivatives as novel building blocks in HIV-protease inhibitors has been developed. The synthesis starts with protected L-phenylalaninols, which were converted to gamma-amino alpha, beta-unsaturated esters in a one-pot procedure. A highly diastereoselective epoxidation of the N-protected (E)-enoates, followed by regioselective ring opening of the corresponding 2,3-epoxy esters with a variety of heteronucleophiles, resulted in 2-heterosubstituted statine derivatives.

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We compared global and regional cerebral blood flow in 11 schizophrenic patients and 11 normal comparison subjects, all over the age of 45 years. The schizophrenic patients had lower global cortical uptake than the control subjects. Among the individual regions of interest, the schizophrenic patients had significant decrements in the left posterior frontal region and in the bilateral inferior temporal regions.

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A decrease in the activity of choline acetyltransferase (ChAT) has been well documented in brains from individuals with Alzheimer's disease (AD) (Bird et al., 1983; McGeer, 1984). Decreased ChAT activity was also found in dialysis encephalopathy victims, but this reduction was less marked than that observed in AD (Yates et al.

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