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SUMMARYObjective: To compare the upper gastrointestinal (GI) and overall tolerability profiles of alendronate 70 mg once weekly with placebo.Research design and methods: This 12-week international, multi-center, randomized, double-blind, placebo-controlled trial included 449 postmenopausal women and men with osteoporosis at 44 sites in 19 countries in Europe, the Americas, Africa, and Asia-Pacific. Subjects were randomized to alendronate 70 mg once weekly or matching placebo in a 1:1 ratio.Main outcome measures: The safety and tolerability of weekly alendronate and placebo were captured as clinical and laboratory adverse events. The primary endpoint was upper GI tolerability based on the incidence of upper GI tract adverse events. Secondary endpoints included the percentage of subjects who discontinued therapy due to a drug-related upper GI adverse event. Change from baseline in bone turnover as measured by the urinary N-telopeptide-collagen crosslinks corrected for creatinine (NTx/Cr) was assessed at 12 weeks as an indicator of efficacy.Results: The percentages of subjects reporting an upper GI tract adverse event in the alendronate 70 mg once weekly group (9.8) and the placebo group (9.4) were similar. The risk difference between the two treatment groups (alendronate minus placebo) was 0.4 [95 confidence interval (CI), –5.1, 5.9]. Percentages of subjects who discontinued due to a drug-related upper GI adverse event were also similar (alendronate 2.7; placebo 2.2; risk difference 0.4, 95 CI, –2.4, 3.3). The overall tolerability profile of alendronate 70 mg once weekly, as measured by the percentage of subjects reporting any adverse event, was similar to that of placebo (risk difference 2.1, 95 CI –6.9,11.0). There was a significant 43.3 (95 CI, –47.9, –38.3) decrease from baseline in urinary NTx/Cr in the alendronate group compared with an 8.0 (95 CI, 1.4, 15.0) increase in the placebo group at Week 12Conclusion: Alendronate 70 mg administered once weekly to women and men with osteoporosis has an upper GI and overall tolerability profile similar to that of placebo.

Mechanical activation leads to a variety of defects in MoO3. The behavior of paramagnetic defects in unmilled MoO3 and in MoO3 mechanically activated in a planetary mill for 600 min was investigated by ESR spectroscopy. MoO3 milled for 600 min, and unmilled MoO3 though in a smaller concentration, contain Mo⁵⁺ ions. N2 treatment at elevated temperatures increases the Mo⁵⁺ concentration in the samples due to oxygen loss. Both MoO3 samples contain octahedrally coordinated Mo⁵⁺ species prior to any treatment which interact with a proton in close proximity. An additional signal is observed in both samples that is characteristic of F centers. An inverse Curie−Weiss behavior between 90 and 300 K indicates the pairing of electrons at lower temperatures. Fivefold coordinated Mo⁵⁺ species in distorted, square-pyramidal symmetry are generated in the bulk of unmilled MoO3 during N2 flushing at 523 and 623 K. MoO3 milled for 600 min contains, besides 6-fold coordinated Mo⁵⁺ in C2v symmetry, a second Mo⁵⁺ species in almost C4v symmetry. The Mo−O distances in the equatorial plane are shortened and these Mo⁵⁺ centers are assigned to a precursor structure of crystallographic shear planes. Besides 6-fold coordinated Mo⁵⁺, tetrahedrally coordinated Mo⁵⁺ centers are also generated, if milled MoO3 is treated in N2 at 623 or 673 K which are assigned to the Mo sites on shear defects protruding from the surface. The total intensity of the Mo⁵⁺ signals follows the Curie−Weiss law between 90 and 200 K. Above 200 K a deviation from linearity is observed. Hence, a considerable part of the Mo⁵⁺ centers does not contribute to the signal intensity at higher temperatures. In situ Raman spectroscopy of mechanically activated MoO3 revealed the formation of some nonstoichiometric MoO3-x after thermal treatment at 673 K in N2 for 1 h. In addition, diffuse reflectance infrared spectroscopy (DRIFTS) was used to characterize the stability of OH groups on the surface of MoO3 and in the bulk of the milled sample. The OH species located in the bulk of MoO3 was found to be stable even at 673 K under flowing N2.

Mechanical activation of solids leads to an increased internal energy caused by the introduction of defects. This can result for example in a reduced surface melting temperature of activated particles, which in turn may affect their sintering behavior. Analogously the spreading behavior of MoO3 over Al2O3 may depend on the mechanical treatment during physically mixing the solids. Differences in the spreading over Al2O3 of unmilled MoO3 and MoO3 that was mechanically activated for 600 min were investigated by SEM/TEM, XPS, ESR, and in situ high-temperature Raman spectroscopy. SEM and EDX analyses of these physical mixtures make surface melting during the calcination very probable. In addition, analysis of XPS spectra also shows that spreading occurs under these conditions. However, spreading in the mixture with milled MoO3 is more effective. ESR spectroscopy shows that Mo⁵⁺ centers are reoxidized after calcining the mixtures with unmilled MoO3 in moist oxygen. For the mixture with milled MoO3 an additionally observed Mo⁵⁺ species in C2v distorted sixfold coordination is stable against oxygen for many hours, independent of the presence or absence of water. This higher stability of this defect species against reoxidation is attributed to an improved stabilizing effect of the Al2O3 support due to a pronounced spreading of mechanically activated MoO3. High-temperature Raman spectroscopy of pure, unmilled MoO3 reveals that a transformation into polymeric species occurs at temperatures above 948 K. At 1053 K, melting is observed and the Raman bands of crystalline MoO3 are lost. Calcination of an unmilled physical mixture of 9 wt % MoO3 and Al2O3 at the considerably lower temperature of 823 K in dry O2 leads to the observation of Raman bands of an amorphous polymeric Mo surface melt. Quenching this sample to room temperature results in a Raman spectrum which is attributed to a glassy surface MoO3 phase. Calcination of the physical mixture milled for 3 h at 823 K also leads to a Raman spectrum of the surface melt. Quenching to 298 K does not lead to a considerable change of the spectrum, this being explained by a more effective spreading of the Mo phase in the mechanically activated mixture. This surface Mo phase is highly reactive toward H2O during rehydration at 298 K, which leads to the formation of a polymeric surface species. A long time spreading experiment at 723 K reveals that this process is considerably slower and less effective at this lower temperature.

The raz1 mutant of Arabidopsis thaliana (L.) Heynh. has been selected as resistant to the toxic proline analogue, azetidine-2-carboxylic acid (2AZ). Seedlings of the mutant tolerated fivefold higher concentrations of 2AZ (ED50 = 0.25 mM) than the wild-type seedlings (ED50 = 0.05 mM). The mutant gene was found to be semi-dominant and the corresponding RAZ1 locus was mapped on chromosome 5 at 69.6±1.8 cM. The resistance to 2AZ could be fully and exclusively accounted for by the lower uptake rate of the proline analogue in the mutant. The influx of L-proline in roots of wild-type seedlings could be dissected into two components: (i) a component with a high affinity and a low capacity for l-proline (Km˜20 gmM, Vmax˜60 nmol·(g FW)-1·h-1) and also a high affinity for L-2AZ (Ki˜40 µM) and (ii) a low-affinity, high-capacity component (Km˜5 mM: Vmax = 1300 nmol·(g FW)-1·h-1). Clearly, the raz1 mutation affects the activity of a high-affinity transporter, because the high-affinity uptake of proline in the mutant was at least fivefold lower than in the wild-type, whereas the low-affinity uptake was unchanged.

At-P5R, a gene encoding the last enzyme of the proline (Pro) biosynthetic pathway in Arabidopsis thaliana, is developmentally regulated. To characterize the cis elements responsible for this developmental regulation, a series of 5' deletions of the At-P5R promoter were transcriptionally fused to a beta-glucuronidase (GUS)-coding region and transformed into Arabidopsis. The complete promoter of At-P5R directs strong GUS activity in root tips, the shoot meristem, guard cells, hydathodes, pollen grains, ovules, and developing seeds, all of which contain rapidly dividing cells and/or are undergoing changes in osmotic potential. This expression pattern is consistent with the function of Pro as an energy, nitrogen, and carbon source and as an osmoticum in response to dehydration. Promoters longer than 212 base pairs (bp) showed the same expression pattern, whereas those shorter than 143 bp did not direct any detectable GUS activity in any organs. This suggests that a 69-bp promoter region located between -212 and -143 bp is necessary to establish the tissue-specific expression of At-P5R during development. The Pro content measured in different organs suggests that, in addition to transcriptional control of the biosynthetic pathway, the transport of Pro may play a role in its distribution within Arabidopsis. Several aspects of the relationship between Pro metabolism and plant physiology are discussed.