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Hydrophobically modified pectin derivatives were prepared by immobilization of long alkyl chains (C12−C18) at various substitution ratios, using two different synthetic pathways, one affording covalent fixation and the other one leading to a mere ionic association. These derivatives display an associative tendency in semidilute as well as in dilute aqueous solutions. This phenomenon, which stems from both intra- and intermolecular interactions between hydrophobic groups, results in the formation of hydrophobic microdomains. The latter can be characterized, especially in the dilute regime, thanks to fluorescence spectroscopy. Fluorescent molecular rotors, as well as pyrene, a classical fluorescence probe of widespread use, witness the variations of the medium polarity. In addition, they can also provide further information, particularly about the local cohesion of the microenvironment of the probe, without performing any complementary experiment, for example, the addition of quenchers together with the fluorescent probe in the polymer solutions. CAC values derived from polarity changes (CACpolarity), using the molecular rotor as well as pyrene as the fluorescence probes, are significantly different from those determined from the cohesion of the microenvironment (CACcohesion), accessible only with the molecular rotor. This latter type of fluorophore may therefore enable us to determine more accurately the actual critical aggregation concentration.

Described is a 67-year-old man whose initial symptoms evoked an obesity-hypoventilation syndrome. Polysomnography showed hypopneas associated with O2desaturation episodes, and no apnea; maximal changes were noted during REM sleep. A few months later, in spite of marked weight loss, acute alveolar hypoventilation occurred and necessitated mechanical ventilatory support. Tracheostomy was performed. The patient appeared to be dependent on nocturnal ventilatory assistance. Diaphragmatic paralysis was noted in addition to clinical and electrodiagnostic evidence of amyotrophic lateral sclerosis. While the patient was not ventilated, a nocturnal recording of SaO2again revealed desaturation episodes partly corrected by O22 L/min administered through the tracheostomy tube. With volume-controlled ventilation, desaturations completely disappeared, although no oxygen enrichment of the air was provided. We speculate that sleep disorders with hypopneas and O2desaturation episodes were the initial symptoms of amyotrophic lateral sclerosis. This leads us to suggest that nonspecific respiratory muscle fatigue frequently seen in COPD might be included in the hypothetic causes of nocturnal hypoxemia.

The aim of this study was to determine the lung levels of metallothionein (MT), a free radical scavenger, because oxygen-derivated free radicals (ODFRs) have been involved both in reperfusion injury of transplanted lungs and in cardiac or renal allograft destruction. First, MT localization was evaluated in 14 normal human lung biopsy specimens. Then, in lung transplant recipients, MT content in BAL fluid (BALF) and its transcription rate in alveolar macrophages (AMs) were determined. The BALFs of 69 patients were separated into six groups: lung transplant recipients in clinically stable condition (CSR), those with acute rejection (AR), asymptomatic cytomegalovirus infection (ACMV), cytomegalovirus pneumonitis (CMVP), bronchiolitis obliterans syndrome (BOS), and patients without transplants who served as control subjects (NTCs). In normal lungs, 83% of AMs were positively stained. MT staining was also observed in pleural endothelial cells and basal cells from bronchial epithelium. In lung transplant recipients, MT levels in BALF were significantly higher in patients with CSR, AR, ACMV, and CMVP compared with NTCs, while during BOS, MT had a significantly lower level compared with other lung transplant groups. However, no difference among groups was found concerning MT-II messenger RNA expression in AMs, showing that, as in normal lung, AMs are not the only cells that produce MT. These data report for the first time to our knowledge MT cell distribution in human lung with specific emphasis on its enhanced levels after lung transplantation, even in the absence of complication. Possible correlation among MT levels, ODFRs, cytokine levels, and corticosteroid treatment during complications of lung transplantation are discussed.

Nitrite anions are easily condensed with aryl halides in the presence of the Complex Base NaNH2-CH3CH2(OCH2CH2)2ONa via the intermediate arynes.

A new preparation of two kinds of potentially biologically active phenylethanolamines is described. The basic reaction of these syntheses is arynic condensation of ketone enolates in the presence of Complex Bases.

Title compounds such as (V) or (VI) are prepared via arynic condensation of phenyl bromide (I) with the enolate (II) and subsequent oxidative cleavage of the oxime resp. the corresponding diol derived from the acetoxy ketone (III).

The base mentioned in the title is generated in situ from sodium amide and diglycol monoethyl ether.

Reaction of the haloarenes (I) with the enolates (II) of cycloalkanedione monoacetals in the presence of sodium amide results in (2 + 2)cycloaddition of the arynes generated in situ, yielding the polycyclic adducts (IIIa) ‐ (IIIg), together with the regioisomer (IVg).