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Hydrostannations of propargylic glycine esters with the new hydrostannation catalyst [Mo(CO)3(CNtBu)3] (MoBI3) gave rise to α‐stannylated allylic esters in good yield and with high regioselectivity. The chelate Claisen rearrangements of these esters allow the syntheses of γ,δ‐unsaturated amino acids with a vinylstannane moiety in the side chain. The amino acids obtained can be further modified by cross‐coupling with various types of electrophiles.

Mo(CO)3(NCtBu)3 (MoBI3) was found to be a suitable catalyst for the regioselective hydrostannation of several types of alkynes, preferentially giving rise to the α-stannylated products. These products are not available under radical reaction conditions, or by using other metal catalysts. This protocol tolerates a wide range of functional groups, and can also be applied to sensitive substrates, which cannot be hydrometallated with the commonly used palladium catalysts.

AbstractThe Polar Vantage XL heart rate monitor provides an ambulatory, inexpensive method of continuously measuring heart rate. To examine the validity of the Polar monitor for measuring heart rate during resting periods and while engaging in two stressful tasks, 30 students participated in a 1-hour laboratory session. Heart rates were measured simultaneously using the Polar monitor and electrocardiography (ECG) during a hand grip exercise and a mental arithmetic task, each preceded by a 4-min resting period. Within-subject correlations between the two devices were significant (mean r= 0.98, P< .001). All correlations, except for three participants, exceeded r= 0.90. Between-task correlation analyses revealed high correlations (i. e., rs ≥ 0.98) between the Polar monitor and ECG. The Polar monitor obtained readings that were slightly, though significantly higher than readings obtained using ECG. The correspondence between observed mean heart rates from the Polar monitor and ECG suggest that the Polar monitor provides a valid measure of heart rate during stationary laboratory tasks.

Acute renal failure (ARF) or renal dysfunction (RD) associated with germanium-induced nephrotoxicity has been reported in 18 patients since 1982. In 2 of these cases the patients died of acute renal and cardiogenic failure. In 17 of 18 cases biopsies showed vacuolar degeneration in renal tubular epithelial cells in the absence of glomerular changes, without proteinuria or hematuria. Accumulated elemental Ge intake in 17 patients over a period of 4 to 36 months ranged between 16 and 328 g, or more than 100 to 2000 times the average estimated dietary intake of Ge for man (1.5 mg/d; range 0.40 to 3.40 mg/d). The biological half-life of Ge is 4.5 days for kidneys, the highest retention level of any organ. The mean concentration of Ge in healthy adult kidneys is 9.0 mg/kg wet weight. In 3 patients studied with Ge-induced RD or ARF, urinary Ge excretion was 9, 15, and 60 ng/mL, compared to > 5 ng/mL in healthy controls, and remained elevated even 12 months after discontinuing supplemental Ge intake. The mechanism for Ge-induced nephrotoxicity remains unknown, although the suspected cause is the inorganic Ge salts, such as germanium dioxide. Sufficient evidence for a role of organogermanium compounds, such as carboxyethyl germanium sesquioxide or citrate-lactate germanate, in Ge-induced nephrotoxicity remains lacking. The recent introduction of over-the-counter Ge "nutritional" supplements in some countries increases the risk of additional cases of Ge-induced nephrotoxicity, especially if appreciable levels of inorganic Ge salts are present and consumed for long periods (> 3 months) at levels above the average daily estimated dietary intake for Ge. Despite promotional claims for over-the-counter Ge preparations as "nutritional" supplements, there is at present no known biological requirement for Ge in any organism; nor has Ge deficiency been demonstrated in any animal. Nephrologists should be alert to the potential of Ge-induced ARF or RD in patients consuming Ge supplements.

Phenol sulphotransferases esterify both endogenous and foreign hydroxylated aromatic compounds with sulphate. Since these enzymes participate in both hormone and drug metabolism, elucidating their regulation at both the enzymic and molecular levels may provide new understanding in several metabolic pathways. The primary structure of a bovine phenol sulphotransferase has been determined by isolation of the corresponding cDNA. Two partial bovine cDNAs were first isolated by probing a tracheal epithelial cell lambda gt11 cDNA library with a rat phenol sulphotransferase cDNA. These clones provided the sequences of the 5′ and 3′ ends of the predicted coding region. A contiguous cDNA was subsequently isolated by PCR using 5′ and 3′ oligonucleotide primers and the cDNA library as the template. The sequence of the resulting approx. 1 kbp cDNA predicted an amino acid sequence that included sequences determined for several tryptic peptides of the purified protein. Antiserum directed to a synthetic N-terminal peptide predicted by the cDNA sequence showed reactivity with the purified enzyme. High-level Trc-promoter-driven expression of the recombinant bovine enzyme was achieved in Escherichia coli. The bovine cDNA was used to determine relative steady-state levels of phenol sulphotransferase transcripts in bovine lung tissues; distal lung parenchymal RNA levels were 6-10-fold greater than those in tracheobronchial epithelium. Using a bronchial epithelial cell culture model, however, cortisol was observed to increase mRNA levels by 5-fold in both a dose- and time-dependent manner; this corresponds to previously reported glucocorticoid stimulation of phenol sulphotransferase activity in this system [Beckmann, Illig and Bartzatt (1994) J. Cell Physiol. 160, 603-610].

NATURAL EXPERT is a product that allows users to build knowledge-based systems. It uses a lazy functional language, NATURAL EXPERT LANGUAGE, to implement backward chaining and provide a reliable knowledge processing environment in which development can take place. Customers from all over the world buy the system and have used it to handle a variety of problems, including applications such as airplane servicing and bank loan assessment. Some of these are used 10,000 times or more per month.

Nutrition and behavior research presents a particularly challenging field of study for scientists. An overview is provided of research on nutrition and behavior of adequately nourished populations in industrialized countries. Discussions and findings from research presented include: refined carbohydrate consumption, maladaptive behavior, behavior disorders and learning; a history of the ‘Feingold diet’ and the basis for its controversy; an examination of recent critiques of research on artificial food dyes and hyperkinesis; indications for dietary intervention of hyperactive preschoolers; the role of iron in behavior disorders; effects of sub-clinical vitamin deficiencies on behavior; trace element analysis studies and violent behavior; and, suggested guidelines for further research into this complex and challenging field. Studies cited are from Canada, France, the United Kingdom, and the United States.

Unification in the equational theory of one-sided distributivity and a multiplicative unit is shown to be decidable. The algorithm is a non-deterministic one that eventually uses a decision algorithm for string unification problems with constant restrictions, which was shown to be decidable by K. Schulz extending the decision algorithm for string unification by Makanin.

A novel three-dimensional nanostructured open-channel metal-organic framework polymer with inclusion of a polyiodide cluster has been synthesized via an oxidation reaction mechanism under hydrothermal conditions. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

Mo(CO)3(NC-t-Bu)3 was found to be a suitable catalyst for the regioselective hydrostannation of several types of alkynes, giving preferentially rise to the α-stannylated products. These products are not available under radical reaction conditions or by using other metal catalysts. This protocol can also be applied to sensitive substrates, which cannot be hydrometalated with the commonly used palladium catalysts.

Cdkn1a, which encodes p21, functions as a major route for p53-mediated cell-cycle arrest. However, the consequence of Cdkn1agene dosage on tumor suppression has not been systematically investigated. Here, we employed BAC transgenesis to generate a Cdkn1aSUPERmouse, which harbors an additional Cdkn1aallele within its natural genomic context. We show that these mice display enhanced cell-cycle arrest and reduced apoptosis in response to genotoxic stress. Furthermore, using a chemically induced skin cancer model and an autochthonous Kras-driven lung adenocarcinoma model, we show that Cdkn1aSUPERmice display a cancer protection phenotype that is indistinguishable from that observed in Tp53SUPERanimals. Moreover, we demonstrate that Tp53and Cdkn1acooperate in mediating cancer resistance, using a chemically induced fibrosarcoma model. Overall, our Cdkn1aSUPERallele enabled us to assess the contribution of Cdkn1ato Tp53-mediated tumor suppression.

ABSTRACTRemarkable efficacy of immune checkpoint inhibition has been reported for several types of solid tumors and early studies in gastric adenocarcinoma are promising. A detailed knowledge about the natural biology of immune checkpoints in gastric adenocarcinoma is essential for clinical and translational evaluation of these drugs. This study is a comprehensive analysis of cytotoxic T lymphocyte associated molecule 4 (CTLA-4) and programmed death 1 ligand 1 (PD-L1) expression in gastric adenocarcinoma. PD-L1 and CTLA-4 were stained on tumor sections of 127 Caucasian patients with gastric adenocarcinoma by immunohistochemistry (IHC) and somatic mutation profiling was performed using targeted next-generation sequencing. Expression of PD-L1 and CTLA-4 on lymphocytes in tumor sections, tumor-draining lymph nodes (TDLN) and peripheral blood were studied by flow-cytometry and immune-fluorescence microscopy in an additional cohort. PD-L1 and CTLA-4 were expressed in 44.9% (57/127) and 86.6% (110/127) of the analyzed gastric adenocarcinoma samples, respectively. Positive tumor cell staining for PD-L1 or CTLA-4 was associated with inferior overall survival. Somatic mutational analysis did not reveal a correlation to expression of PD-L1 or CTLA-4 on tumor cells. Expression of PD-1 (52.2%), PD-L1 (42.2%) and CTLA-4 (1.6%) on tumor infiltrating T cells was significantly elevated compared to peripheral blood. Of note, PD-1 and PD-L1 were expressed far higher by tumor-infiltrating lymphocytes than CTLA-4. In conclusion, specific immune checkpoint-inhibitors should be evaluated in this disease and the combination with molecular targeted therapies might be of benefit. An extensive immune monitoring should accompany these studies to better understand their mode of action in the tumor microenvironment.

No relevant conflicts of interest to declare.

To the Editor.—Patients with cancer frequently search their nutritional history for dietary factors supposedly etiologic in the genesis of their disease. After the diagnosis, they may originate changes in their diet in an effort to improve their general health and to control the cancer.We evaluated the frequency and the type of dietary changes initiated by patients after the diagnosis of cancer. We obtained a nutritional history in 100 consecutive patients with solid tumors admitted to the Medical Oncology Service at the University of Minnesota Medical Center. An arbitrary criterion for inclusion in the study was a diagnosis of cancer of at least three months prior to admission for the patient to have some time to consider and institute dietary changes.Eighteen patients started taking multivitamins or minerals or "nutrients" after the diagnosis. Three additional patients modified their diet and started taking multivitamins. Another four patients modified only their

The article offers information on the revival of Charles Ludlam's one-man show "The Mystery of Irma Vep," performed at the Urban Stages in New York City through July 15, 2007. The horror spoof was named the Best Play of the Year by "Time Magazine" and "The New York Times" during its original run in 1984.

The article offers information on Station Studios, a gym developed by Russian scientists in 1967 to enhance the performance of their Olympic team, located in New York. The sports facility features vibration training regime and far-infrared radiant (FIR) saunas. According to executive director and co-owner Andrew Luke Barile, a second full service Vibration Studio is being constructed on the Upper East Side as well as in the Palm Beach area.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Presents information on several health issues and topics. Why mild hypertension need to be treated; Danger in using colloidal minerals; Limitations of melatonin; Prevention of vaginal yeast infections.

Alleges that a deficiency of the mineral zinc may be central to many cases of eating disorders. Four levels for treatment of eating disorders; Conditions associated with zinc deficiency; Anorexia nervosa; Bulimia.