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A spatially unequal distribution of dentists or dental care professionals (D/DCPs), such as therapists or hygienists, could reduce the quality of health services and increase health inequities. This review describes the interventions available to enhance this spatial distribution and systematically assesses their effectiveness. Electronic databases (Cochrane CENTRAL, Medline, Embase, CINAHL) were searched and cross‐referencing was performed using a standardised searching algorithm. Randomised and non‐randomised controlled trials, controlled before‐and‐after studies and interrupted time series were included. Studies investigating a minimum of one of four interventions (educational, financial, regulatory and supportive) were included. The primary outcome was the spatial distribution of D/DCPs. Secondary outcomes were access, quality of services and equity or adverse effects. This review was registered (CRD42015026265). Of 4,885 articles identified, the full text of 201 was assessed and three (all investigating national policy interventions originally not aiming to change the distribution of D/DCPs) were included. In one Japanese study spanning 1980 to 2000, the unequal spatial distribution of dentists decreased alongside a general increase in the number of dentists. It remained unclear if these findings were associated. In a second Japanese study, an increase in the number of dentists was found in combination with a postgraduate training programme implemented in 2006, and this occurred alongside an increasingly unequal distribution of dentists, again without proof of cause and consequence. A third study from Taiwan found the introduction of a national universal‐coverage health insurance to equalise the distribution of dentists, with statistical association between this equalisation and the introduction of the insurance. The effectiveness of interventions to enhance the spatial distribution of D/DCPs remains unclear.

abstractObjective: Oral adenosine-5′-triphosphate (ATP) administration has failed to increase plasma ATP levels; however, chronic supplementation with ATP has shown to increase power, strength, lean body mass, and blood flow in trained athletes. The purpose of this study was to investigate the effects of ATP supplementation on postexercise ATP levels and on muscle activation and excitability and power following a repeated sprint bout.Methods: In a double-blind, placebo-controlled, randomized design, 42 healthy male individuals were given either 400 mg of ATP as disodium salt or placebo for 2 weeks prior to an exercise bout. During the exercise bout, muscle activation and excitability (ME, ratio of power output to muscle activation) and Wingate test peak power were measured during all sprints. ATP and metabolites were measured at baseline, after supplementation, and immediately following exercise.Results: Oral ATP supplementation prevented a drop in ATP, adenosine-5′-diphosphate (ADP), and adenosine-5′-monophosphate (AMP) levels postexercise (p< 0.05). No group by time interaction was observed for muscle activation. Following the supplementation period, muscle excitability significantly decreased in later bouts 8, 9, and 10 in the placebo group (−30.5, −28.3, and −27.9%, respectively; p< 0.02), whereas ATP supplementation prevented the decline in later bouts. ATP significantly increased Wingate peak power in later bouts compared to baseline (bout 8: +18.3%, bout 10: +16.3%).Conclusions: Oral ATP administration prevents exercise-induced declines in ATP and its metabolite and enhances peak power and muscular excitability, which may be beneficial for sports requiring repeated high-intensity sprinting bouts.

A familial mutation in SRY, the gene coding for the testis-determining factor TDF, was identified in an XY female with gonadal dysgenesis, her father, her two brothers and her uncle. The mutation consists of a T to C transition in the region of the SRY gene coding for a protein motif known as the high mobility group (HMG) box, a protein domain known to confer DNA-binding specificity on the SRY protein. This point mutation results in the substitution, at amino acid position 109, of a serine residue for phenylalanine, a conserved aromatic residue in almost all HMG box motifs known. This F109S mutation was not found in 176 male controls. When recombinant wildtype SRY and SRYF109S mutant protein were tested in vitro for binding to the target site AAC AAAG, no differences in DNA-binding activity were observed. These results imply that the F109S mutation either is a rare neutral sequence variant, or produces an SRY protein with slightly altered in vivo activity, the resulting sex phenotype depending on the genetic back-ground or environmental factors.

After Sauvage et al. and Stoddart et al. had developed the now commonly used and well-established catenane and rotaxane synthesis utilizing phenanthroline/Cu+and bipyridinium/crown units, a new way to synthesize mechanical bonds was discovered in 1992—the synthesis of amide-linked catenanes and rotaxanes around a neutral template. The formation of the template, which leads to the host–guest bond, does not proceed by covalent or ionic interaction, but by weak supramolecular interactions, such as hydrogen bonding, p-stacking, p-donor–p-acceptor interaction, and steric complementarity. The simple synthetic units (arene dicarboxylic acid dichlorides and diamines) can be varied in an astonishing number of ways, few steps are required to obtain the target molecules, and the yields of these syntheses approach those of ordinary organic syntheses. After the preparation of [2]catenanes, it took only a few years to prepare [2]-, [3]-, and bis[2]-rotaxanes of the amide type. The introduction of sulfonamide groups enabled alkylation of the sulfonamide nitrogen atom, and this made chemical reactions with catenanes and rotaxanes feasible. Intra- and intermolecular connections of catenanes and rotaxanes were then possible, and a molecule with the topology of a “pretzel” has recently been prepared. This allowed new insights into the molecular recognition processes of neutral guest and host substances, as well as further understanding of these processes in template synthesis, isomerism in catenanes, and the regioselectivity of the formation of catenane isomers. Competitive binding studies of guest molecules in the cavity of concave receptors with more than one binding site can be perfomed. These studies might result in higher synthetic yields of molecules with mechanical bonds and lead to further progress in the development of supramolecular nanostructures and molecular switches. Prepared from simple diacid dichlorides and diamines, catenanes and rotaxanes, once thought exotic, can be synthesized in up to 40% yield, sometimes in one-step syntheses. The process of threading a stringlike molecule through a neutral template discovered in 1992 is supported by hydrogen bonding and p–p interactions. The quantities of these mechanically bonded molecules are sufficient for further preparative conversions; even complicated topologies like a “molecular pretzel” [Equation (a)] have already been prepared.

Nachdem Sauvage et al. und Stoddart et al. in den achtziger Jahren Synthesen für Catenane und Rotaxane mit Phenanthrolin‐ bzw. Bipyridinium‐Kronenether‐Bausteinen entwickelt hatten, wurde vor wenigen Jahren eine neue Strategie zur Herstellung mechanischer Bindungen gefunden: die über ein neutrales Templat verlaufende Synthese amidverknüpfter Catenane und Rotaxane. Die Wirt‐Gast‐Bindung bei der Bildung der Schablone beruht nicht auf Kovalenz‐ oder Ionenwechselwirkungen, sondern auf schwachen supramolekularen Wechselwirkungen: Wasserstoffbrücken, π‐Stapelung, π‐Donor‐π‐Acceptor‐Wechselwirkungen und sterische Komplementarität. Die einfachen Synthesebausteine (Arendicarbonsäuredichloride und Diamine) können in bemerkenswert weiten Grenzen variiert werden, die Zahl der Synthesestufen ist gering, und die Ausbeuten erreichen diejenigen herkömmlicher Synthesen. In wenigen Jahren wurden auf diese Weise außer [2]Catenanen [2]‐, [3]‐ und Bis[2]‐rotaxane des Amidtyps hergestellt. Eingeführte Sulfonamidgruppen ermöglichten Alkylierungen an deren Stickstoffatomen, wodurch präparative chemische Umsetzungen mit Catenanen und Rotaxanen erschlossen wurden. So ließen sich Catenane und Rotaxane intra‐ und intermolekular verknüpfen, wobei auch eine Verbindung mit der Topologie einer Brezel entstand. Damit werden neue Einblicke in molekulare Erkennungsprozesse zwischen elektrisch ungeladenen Wirt‐ und Gastsubstanzen, in Templatsynthesen, in Isomerietypen bei Catenanen und in die Regioselektivität der Bildung von Catenanisomeren möglich. Konkurrenzreaktionen beim Andocken von Gastmolekülen im Hohlraum von konkaven Rezeptormolekülen mit mehreren Bindungsstellen lassen sich studieren. Davon erhofft man sich für die Zukunft Fortschritte bei der Synthese von Molekülen mit mechanischen Bindungen in hohen Ausbeuten, beim supramolekularen Aufbau von Nanostrukturen sowie bei molekularen Schaltern. Aus einfachen Disäuredichloriden und Diaminenlassen sich zum Teil in Einstufensynthesen amidverknüpfte Catenane und Rotaxane in Ausbeuten bis zu 40% herstellen. Die über ein neutrales Templat verlaufende Reaktion wird durch Wasserstoffbrücken und π‐π‐Wechselwirkungen unterstützt. Die Mengen, in denen diese mechanisch verknüpften Moleküle zugänglich sind, ermöglichen weitere präparative Umsetzungen, so daß selbst komplizierte Gebilde wie eine „molekulare Brezel”︁ synthetisiert werden konnten [Gl. (a)].

The preparative syntheses of new nano‐sized rotaxane assemblies are described, namely, of the first tris[2]rotaxane, 15, the first bis[2]rotaxane connected at the axles, 4, and the first [3]rotaxane with two different axles, 12(unsymmetrical “bis[2]rotaxane”). These syntheses were made possible by the directed incorporation of a sulfonamide group into the amide‐linked rotaxane building blocks. The sulfonamide moiety can be used as a functional group in alkylation reactions, allowing the further attachment of building blocks in good yields. The successful synthesis of these new rotaxane architectures demonstrates the synthetic potential of this sulfonamide strategy in the preparation of multirotaxane and dendritic rotaxane structures.

Two loci on the short arm of the human Y chromosome have recently been described as candidates for the testis determining factor (TDF); namely, ZFY, and a locus distal to ZFY, near the pseudoautosomal boundary. We have previously reported on seven 46,XX true hermaphrodites and one 45,X mixed gonadal dysgenesis case all presenting with testicular tissue in their gonads in the apparent absence of Y-specific DNA sequences. A reanalysis of these cases shows them all to lack ZFY, but one 46,XX true hermaphrodite carries sequences next to the Y pseudoautosomal boundary. This case provides further evidence for assigning the TDF locus very close to the pseudoautosomal region on Yp.