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The successful intercalation of a variety of organic dicarboxylates and sulfonates into the novel LDHs [MAl4(OH)12](NO3)2·yH2O (M = Zn, Cu, Ni and Co) has recently been reported [G. R. Williams, T. G. Dunbar, A. J. Beer, A. M. Fogg and D. O’Hare, J. Mater. Chem., DOI: 10.1039/b514874j, ref. , the preceeding paper in this issue]. A number of the guests intercalated are isomeric, and the separation of mixtures of these isomers could be useful industrially. Benzenedicarboxylates and napthalenesulfonates were chosen to be the focus of these studies owing to their industrial importance. Preferential intercalation is seen for 1,4-benzenedicarboxylate over 1,2-benzenedicarboxylate, and for 2-naphthelenesulfonate over 1-naphthalanesulfonate. Optimum choice of the reaction conditions can allow almost 100% selectivity for one isomer over another in each case. The intercalation of 1,5-naphthalenedisulfonte over 2,6-naphthalenedisulfonate is found to be less selective (between 45% and 90% of the guest intercalated is 1,5-NDS dependent on the intercalation conditions). The isomer intercalated preferentially can be controlled by the reaction conditions, and by appropriate choice of conditions an almost complete separation of a mixture of these isomers is possible.

In 1885 Gilles de la Tourette described a striking syndrome of motor and verbal tics, with uncontrollable gesticulations and verbal outbursts, especially of a profane or scatological nature (coprolalia).1 As currently defined, Tourette's syndrome encompasses several neurological disorders, including echolalia and palilalia (invented words), obsessive-compulsive behaviour, and occasionally self mutilation.2 Subjects often have a fascination with rhymes, riddles, and word play.3 4 Interestingly, Tourette's syndrome has been linked with artistic creativity, and there has been speculation that Mozart and Dr Samuel Johnson may have been sufferers.4 5 We believe that Tourette's syndrome could also underlie the bizarre and hitherto unexplained behaviour of one of the best known yet most enigmatic characters of 20th century English literature. The case of SN, a male red squirrel (Sciurus vulgaris leucourus) of indeterminate age, was reported in detail by Potter.6 SN came from an extensive family with no apparent history of neurological or other disease. He is described as “excessively impertinent in his manners” and was a source of great embarrassment to his family and of nearly fatal irritation to the local owl, a noted carnivore. He contrasts sharply with his peers, who were placid, well behaved, and content …

The intercalation reactions have been studied using in situ energy dispersive X-ray diffraction; ordered second stage heterostructures were observed as intermediate phases, which is almost unprecedented for rigid layer host materials.

Anionic and neutral complexes of europium and terbium with tetraaza phosphinate ligands are formed rapidly and are kinetically stable in vivo; the tetrakis(benzylphosphinate) terbium complex luminesces strongly via excitation into the proximate benzyl group involving efficient intramolecular energy transfer.

Photoelectric Plethysmography (PPG) Was Used to investigate blood flow changes closeto superficial subcutaneous injection sites. As a validation procedure, the PPG response to subcutaneous injection of a known hyperemic agent, prostaglandin E, (10−5 M), was shown to correlate strongly with subcutaneous blood flow changes estimated by the established technique of133Xe washout. Changes in blood flow over the subcutaneous injection sites of insulin (Actrapid) and insulin diluent were measured by photoelectric plethysmography in six nondiabetics and in six stable and seven brittle insulin-dependent diabetics. In all subject groups, an acute increase in local blood flow was seen within 2 min of both insulin and diluent injections, probably caused by injection trauma. At diluent injection sites, this acute hyperemia faded rapidly, blood flow returning to preinjection levels within 15–20 min, and there was no further increase in blood flow in any of the subjects. Insulin injected into the nondiabetics and stable diabetics caused a pronounced increase in local blood flow, sustained for at least 60 min after injection. In the brittle diabetics, however, there was no prolonged local hyperemia, the response being significantly less than that seen in both the nondiabetics and the stable diabetics. Insulin-related hyperemia close to injection (or infusion) sites may be important in subcutaneous insulin absorption. Its near-absence in brittle diabetics may contribute to the impaired response to subcutaneous insulin characteristic of these patients.

Vibration perception threshold was measured with a biothesiometer by a single observer at both medial malleoli and both big toes in 110 diabetic patients aged 15-65 selected at random and in 64 non-diabetic subjects aged 20-65. The vibration perception threshold showed appreciable individual variation both between contralateral sites and between ipsilateral sites, differing by at least 30% between the big toes in 26 (24%) of the diabetic patients and 16 (25%) of the non-diabetic group. Variability between sites was significantly greater in the diabetics than the normal subjects. The vibration perception threshold exceeded published normal values at one or more sites in 22 of the diabetic patients but at all four sites in only four. The wide variability in vibration perception threshold among sites may be due to the tissue characteristics locally and, in diabetic patients, possibly to asymmetric neuropathy. Biothesiometer readings at single or unilateral sites may be unrepresentative or misleading.

WSTEP . Celem badania by³o porownanie wp³ywu stosowania dwoch rodzajow diety ¶rodziemnomorskiej (MedDiet) i diety niskot³uszczowej na zapadalno¶ae na cukrzyce. MATERIA£ I METODY . W badaniu analizowano 3 grupy osob niechoruj±cych na cukrzyce licz±ce ³±cznie 418 osob w wieku 55–80 lat, ktore rekrutowano w jednym z o¶rodkow (PREDIMED-Reus w po³nocno-wschodniej Hiszpanii) bior±cych udzia³ w du?ym badaniu Prevencion con Dieta Mediterranea (PREDIMED), oceniaj±cym skuteczno¶ae interwencji ?ywieniowych w prewencji pierwotnej u osob z grupy wysokiego ryzyka sercowo-naczyniowego. Uczestnikow przydzielono losowo do grupy odbywaj±cej szkolenie na temat diety niskot³uszczowej (grupa kontrolna) lub jednej z dwoch grup stosuj±cych diety ¶rodziemnomorskie, z ktorych pierwsza zosta³a dodatkowo wzbogacona o oliwe z oliwek (1 l/tydz.), a druga o mieszanke orzechow (30 g dziennie). Diety nie wi±za³y sie z ilo¶ciowymi ograniczeniami spo?ywanych pokarmow, nie wymagano zwiekszenia aktywno¶ci fizycznej. G³ownym punktem koncowym by³a zapadalno¶ae na cukrzyce, rozpoznawana wed³ug kryteriow American Diabetes Association . WYNIKI . Po okresie obserwacji, ktorego mediana wynosi³a 4 lata, zapadalno¶ae na cukrzyce wynosi³a 10,1% (95% CI 5,1–15,1), 11,0% (5,9–16,1) i 17,9% (11,4–24,4) w grupach stosuj±cych odpowiednio MedDiet z oliw± z oliwek, MedDiet z orzechami i diete niskot³uszczow± (grupa kontrolna). W analizie wielowymiarowej skorygowany hazard wzgledny zachorowania na cukrzyce w grupach stosuj±cych diete ¶rodziemnomorsk± z oliw± i orzechami wynosi³ odpowiednio 0,49 (0,25–0,97) i 0,48 (0,24–0,96) w stosunku do grupy kontrolnej. Po po³±czeniu obu grup stosuj±cych diete ¶rodziemnomorsk± i porownaniu z grup± kontroln± zapadalno¶ae na cukrzyce zmniejszy³a sie o 52% (27–86). W obu badanych grupach istnia³a odwrotna zale?no¶ae miedzy ¶ci¶lejszym przestrzeganiem diety a zapadalno¶ci± na cukrzyce. Stwierdzono, ?e ryzyko zachorowania na cukrzyce zmniejszy³o sie mimo braku istotnych zmian masy cia³a i aktywno¶ci fizycznej. WNIOSKI . Dieta ¶rodziemnomorska bez ograniczenia liczby przyjmowanych kalorii jest skuteczna w prewencji cukrzycy u osob obarczonych wysokim ryzykiem sercowo-naczyniowym. Diabetes Care PL 2011, tom 8, nr 1, s. 21–28

Falls in blood glucose induce hunger and initiate feeding. The lateral hypothalamic area (LHA) contains glucose-sensitive neurons (GSNs) and orexin neurons, both of which are stimulated by falling blood glucose and are implicated in hypoglycemia-induced feeding. We combined intracellular electrophysiological recording with fluorescein labeling of GSNs to determine their neuroanatomic and functional relationships with orexin neurons. Orexin A (1 μmol/l) caused a 500% increase (P < 0.01) in spontaneous firing rate and rapid and lasting depolarization that was tetrodotoxin-resistant and thus a direct postsynaptic effect. Orexin A altered the intrinsic neuronal properties of GSNs, consistent with increased excitability. Confocal microscopy showed that GSNs were intimately related to orexin neurons: orexin-immunoreactive axons were frequently entwined around GSN dendrites, establishing close and putatively synaptic contacts. Orexin-cell axons also passed in close proximity to glucose-responsive neurons, which are inhibited by low glucose, but orexin A caused smaller depolarization than on GSNs and only a 200% increase in spontaneous firing rate (P < 0.05 vs. GSN). We conclude that GSNs are specific target neurons for orexin A and suggest that they may mediate, at least in part, the acute appetite-stimulating effect of orexin A. Orexin neurons may regulate GSNs so as to control the onset and termination of hypoglycemia-induced feeding.

The potential of the layered gadolinium hydroxide (LGdH) [Gd2(OH)5]Cl·yH2O (LGdH-Cl) for simultaneous drug delivery and magnetic resonance imaging was explored in this work. Three non-steroidal anti-inflammatory drugs (diclofenac [dic], ibuprofen [ibu], and naproxen [nap]) were intercalated into LGdH-Cl for the first time, using three different routes (ion exchange intercalation, coprecipitation, and exfoliation-self-assembly). X-ray diffraction, elemental microanalysis and IR spectroscopy confirmed successful incorporation of the drug into the interlayer spaces of the LGdH in all cases. From a comparison of the guest anion sizes and interlayer spacings, the active ingredients are believed to adopt intertwined bilayer configurations between the LGdH layers. The materials prepared by coprecipitation in general have noticeably higher drug loadings than those produced by ion exchange or self-assembly, as a result of the incorporation of some neutral drug into the composites. The LGdH-drug intercalates are stable at neutral pH, but rapidly degrade in acidic conditions to free Gd3+ into solution. While LGdH-nap releases its drug loading into solution very rapidly (within ca. 1.5 h) at pH 7.4, LGdH-dic shows sustained release over 4 h, and LGdH-ibu extends this to 24 h. The latter composites therefore can be incorporated into enteric-coated tablets to provide sustained release in the small intestine. The drug intercalates are highly biocompatible and retain the proton relaxivity properties of the parent LGdH-Cl, with the materials most promising for use as negative contrast agents in MRI. Overall, the LGdH-drug intercalation compounds appear to have great potential for use in theranostic applications.

This manuscript reports a new type of drug-loaded core-shell nanofibers that provide tunable biphasic release of quercetin. The nanofibers were fabricated using a modified coaxial electrospinning process, in which a polyvinyl chloride (PVC)-coated concentric spinneret was employed. Poly (vinyl pyrrolidone) (PVP) and ethyl cellulose (EC) were used as the polymer matrices to form the shell and core parts of the nanofibers, respectively. Scanning and transmission electron microscopy demonstrated that the nanofibers had linear morphologies and core-shell structures. The quercetin was found to be present in the nanofibers in the amorphous physical status, on the basis of X-ray diffraction results. In vitro release profiles showed that the PVP shell very rapidly freed its drug cargo into the solution, while the EC core provided the succedent sustained release. Variation of the drug loading permitted the release profiles to be tuned.