Adjunctive Rifampicin Increases Antibiotic Efficacy in Group A Streptococcal Tissue Infection Models.

Biofilm has recently been highlighted as a complicating feature of necrotizing soft tissue infections (NSTI) caused by Streptococcus pyogenes (i.e., group A Streptococcus [GAS]) contributing to a persistence of bacteria in tissue despite prolonged antibiotic therapy. Here, we assessed the standard treatment of benzylpenicillin and clindamycin with or without rifampin in a tissue-like setting. Antibiotic efficacy was evaluated by CFU determination in a human organotypic skin model infected for 24 or 48 h with GAS strains isolated from NSTI patients. Antibiotic effect was also evaluated by microcalorimetric metabolic assessment in in vitro infections of cellular monolayers providing continuous measurements over time. Adjunctive rifampin resulted in enhanced antibiotic efficacy of bacterial clearance in an organotypic skin tissue model, 97.5% versus 93.9% (P = 0.006). Through microcalorimetric measurements, adjunctive rifampin resulted in decreased metabolic activity and extended lag phase for all clinical GAS strains tested (P < 0.05). In addition, a case report is presented of adjunctive rifampin treatment in an NSTI case with persistent GAS tissue infection. The findings of this study demonstrate that adjunctive rifampin enhances clearance of GAS biofilm in an in vitro tissue infection model.

Visual word form processing deficits driven by severity of reading impairments in children with developmental dyslexia.

The visual word form area (VWFA) in the left ventral occipito-temporal (vOT) cortex is key to fluent reading in children and adults. Diminished VWFA activation during print processing tasks is a common finding in subjects with severe reading problems. Here, we report fMRI data from a multicentre study with 140 children in primary school (7.9-12.2 years; 55 children with dyslexia, 73 typical readers, 12 intermediate readers). All performed a semantic task on visually presented words and a matched control task on symbol strings. With this large group of children, including the entire spectrum from severely impaired to highly fluent readers, we aimed to clarify the association of reading fluency and left vOT activation during visual word processing. The results of this study confirm reduced word-sensitive activation within the left vOT in children with dyslexia. Interestingly, the association of reading skills and left vOT activation was especially strong and spatially extended in children with dyslexia. Thus, deficits in basic visual word form processing increase with the severity of reading disability but seem only weakly associated with fluency within the typical reading range suggesting a linear dependence of reading scores with VFWA activation only in the poorest readers.

Effectiveness of a standardized patient education program on therapy-related side effects and unplanned therapy interruptions in oral cancer therapy: a cluster-randomized controlled trial.

PURPOSE: Oral agents for cancer treatment are increasingly prescribed due to their benefits. However, oral cancer medications are difficult to handle and have a considerable potential for side effects. This type of therapy requires a high level of self-management competence by the patient. A standardized patient education program provided by physicians and oncology nurses may positively influence the handling of oral agents. The aim of the study was to evaluate the impact of a standardized patient education program provided by specially trained oncology nurses on therapy management regarding side effects and unplanned therapy interruptions. METHODS: One hundred sixty-five patients from 28 office-based oncology practices from all over Germany participated in this cluster-randomized controlled study. Patients of both intervention (n = 111) and standard care groups (n = 54) received the usual oncologist counseling; in addition, the patients from the intervention group (k = 17 practices) received an education from specially trained oncology nurses. The time of observation was 3 months per patient. RESULTS: The patients of the intervention group reported fewer side effects (skin rash, pain, fatigue, nausea, vomiting). Patients in the standard care group interrupted the therapy more frequently without informing their oncologist, compared to the intervention group. CONCLUSIONS: Patients benefit from a standardized patient education program provided by specially trained oncology nurses. They tend to handle side effects and critical situations better.

Combined spiroergometry and 31 P-MRS of human calf muscle during high-intensity exercise.

Simultaneous measurements of pulmonary oxygen consumption (VO2 ), carbon dioxide exhalation (VCO2 ) and phosphorus magnetic resonance spectroscopy (31 P-MRS) are valuable in physiological studies to evaluate muscle metabolism during specific loads. Therefore, the aim of this study was to adapt a commercially available spirometric device to enable measurements of VO2 and VCO2 whilst simultaneously performing 31 P-MRS at 3 T. Volunteers performed intense plantar flexion of their right calf muscle inside the MR scanner against a pneumatic MR-compatible pedal ergometer. The use of a non-magnetic pneumotachograph and extension of the sampling line from 3 m to 5 m to place the spirometric device outside the MR scanner room did not affect adversely the measurements of VO2 and VCO2 . Response and delay times increased, on average, by at most 0.05 s and 0.79 s, respectively. Overall, we were able to demonstrate a feasible ventilation response (VO2 = 1.05 ± 0.31 L/min; VCO2 = 1.11 ± 0.33 L/min) during the exercise of a single calf muscle, as well as a good correlation between local energy metabolism and muscular acidification (τPCr fast and pH; R2 = 0.73, p < 0.005) and global respiration (τPCr fast and VO2 ; R2  = 0.55, p = 0.01). This provides improved insights into aerobic and anaerobic energy supply during strong muscular performances.

Granule size distributions after twin-screw granulation - Do not forget the feeding systems.

The aim of this study was to investigate the influence of qualitatively different powder feeder performances on resulting granule size distributions after twin-screw granulation of a highly drug loaded, hydrophobic mixture and a mannitol powder. It was shown that powder feeder related problems usually cannot be identified by trusting in the values given by the feeder. Therefore, a newly developed model for the evaluation of the performance of powder feeders was introduced and it was tried to connect this model to residence time distributions in twin-screw granulation processes. The influence of feeder performances on resulting granule size distributions varied, depending on the applied screw configuration and the used powder. Regarding the hydrophobic and highly drug loaded formulation, which was granulated at an L/S-ratio of 0.5, a pure conveying screw and a medium kneading configuration, consisting of 60° kneading blocks were negatively influenced by poor feeder settings. For optimal settings more narrow distributions could be obtained. For an extensive kneading configuration good and poor settings resulted in mono-modal granule size distributions but were differing in the overall size. Mannitol, a model substance for a liquid sensitive formulation was granulated at an L/S-ratio of 0.075. It was even more important to maintain optimal feeding as mannitol was highly affected by poor feeder performances. Even an extensive kneading configuration could not level the errors in powder feeder performance, resulting in qualitatively different granule size distributions. The results of this study demonstrate the importance of detailed knowledge about applied feeding systems to gain optimal performance in twin-screw granulation.

Simplified formulations with high drug loads for continuous twin-screw granulation.

As different batches of the same excipients will be intermixed during continuous processes, the traceability of batches is complicated. Simplified formulations may help to reduce problems related to batch intermixing and traceability. Twin-screw granulation with subsequent tableting was used to produce granules and tablets, containing drug, disintegrant and binder (binary and ternary mixtures), only. Drug loads up to 90% were achieved and five different disintegrants were screened for keeping their disintegration suitability after wetting. Granule size distributions were consistently mono-modal and narrow. Granule strength reached higher values, using ternary mixtures. Tablets containing croscarmellose-Na as disintegrant displayed tensile strengths up to 3.1MPa and disintegration times from 400 to 466s, resulting in the most robust disintegrant. Dissolution was overall complete and above 96% within 30 min. Na-starch glycolate offers tensile strengths up to 2.8MPa at disintegration times from 25s to 1031s, providing the broadest application window, as it corresponds in some parts to different definitions of orodispersible tablets. Tablets containing micronized crospovidone are not suitable for immediate release, but showed possibilities to produce highly drug loaded, prolonged release tablets. Tablets and granules from simplified formulations offer great opportunities to improve continuous processes, present performances comparable to more complicated formulations and are able to correspond to requirements of the authorities.

Lack of replication for the myosin-18B association with mathematical ability in independent cohorts.

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance. We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible. We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities.

A common variant in myosin-18B contributes to mathematical abilities in children with dyslexia and intraparietal sulcus variability in adults.

The ability to perform mathematical tasks is required in everyday life. Although heritability estimates suggest a genetic contribution, no previous study has conclusively identified a genetic risk variant for mathematical performance. Research has shown that the prevalence of mathematical disabilities is increased in children with dyslexia. We therefore correlated genome-wide data of 200 German children with spelling disability, with available quantitative data on mathematic ability. Replication of the top findings in additional dyslexia samples revealed that rs133885 was a genome-wide significant marker for mathematical abilities (P(comb) = 7.71 × 10(-10), n = 699), with an effect size of 4.87%. This association was also found in a sample from the general population (P = 0.048, n = 1080), albeit with a lower effect size. The identified variant encodes an amino-acid substitution in MYO18B, a protein with as yet unknown functions in the brain. As areas of the parietal cortex, in particular the intraparietal sulcus (IPS), are involved in numerical processing in humans, we investigated whether rs133885 was associated with IPS morphology using structural magnetic resonance imaging data from 79 neuropsychiatrically healthy adults. Carriers of the MYO18B risk-genotype displayed a significantly lower depth of the right IPS. This validates the identified association between rs133885 and mathematical disability at the level of a specific intermediate phenotype.

Evidence for the involvement of ZNF804A in cognitive processes of relevance to reading and spelling.

Previous studies have shown that individuals with schizophrenia and dyslexia display common neurocognitive abnormalities. The aim of the present study was to determine whether known schizophrenia-risk genes contribute to dyslexia risk or to disease-relevant cognitive functions. For this purpose, we genotyped the schizophrenia-associated risk variants within zinc-finger protein 804A (ZNF804A), transcription-factor 4 and neurogranin in a large dyslexia case-control sample. We tested all variants for association with dyslexia (927 cases, 1096 controls), and with eight language-relevant cognitive processes (1552 individuals). We observed six significant associations between language-relevant traits and the ZNF804A-variant rs1344706. Interestingly, the ZNF804A schizophrenia risk variant was associated with a better cognitive performance in our data set. This finding might be consistent with a previously reported ZNF804A association in schizophrenia, in which patients carrying the schizophrenia-risk allele at rs1344706 showed a better performance in two memory tests. In conclusion, the present study provides evidence that ZNF804A might have a role in cognitive traits of relevance to reading and spelling, and underlines the phenotypic complexity that might be associated with ZNF804A.

Immunogenicity and antigenic properties of Pf332-C231, a fragment of a non-repeat region of the Plasmodium falciparum antigen Pf332.

Antigen Pf332, a megadalton protein has been shown to be associated with the membrane of infected erythrocytes. Detailed functional studies on the antigen have remained hampered by the cross-reactive nature of antibodies generated to Pf332. Pf332-C231, identified in the C-terminal region of Pf332 was cloned and antibodies against the C231 fragment were shown to react with intact Pf332 antigen by both immunofluorescence and immunoblotting analyses. Antibodies to C231 inhibited in vitro Plasmodium falciparum growth efficiently. In addition, human sera from malaria-exposed individuals reacted with recombinant C231. We show that Pf332-C231 represents a functional domain and is expected to facilitate further studies on Pf332 as a potential target for protective immune responses and the function of the antigen.

Fourteen new di- and tetranucleotide microsatellite loci for the critically endangered Indian tiger (Panthera tigris tigris).

We describe 11 dinucleotide and three tetranucleotide microsatellite loci for the critically endangered Indian tiger, Panthera tigris tigris. All of them were polymorphic with four to nine alleles per locus and an observed heterozygosity between 0.13 and 1.0. All primers also amplify microsatellite loci in leopard, Panthera pardus, and 12 primer pairs yielded reproducible results in domestic cat, Felis catus. These new microsatellites specifically developed for Indian tiger - in combination with those already available - comprise a reasonable number of loci to genetically analyse wild and captive populations of this illustrative species and might allow for recognition of individual tigers.

Local adaptation and pronounced genetic differentiation in an extremophile fish, Poecilia mexicana, inhabiting a Mexican cave with toxic hydrogen sulphide.

We investigated genetic differentiation and migration patterns in a small livebearing fish, Poecilia mexicana, inhabiting a sulfidic Mexican limestone cave (Cueva del Azufre). We examined fish from three different cave chambers, the sulfidic surface creek draining the cave (El Azufre) and a nearby surface creek without the toxic hydrogen sulphide (Arroyo Cristal). Using microsatellite analysis of 10 unlinked loci, we found pronounced genetic differentiation among the three major habitats: Arroyo Cristal, El Azufre and the cave. Genetic differentiation was also found within the cave between different pools. An estimation of first-generation migrants suggests that (i) migration is unidirectional, out of the cave, and (ii) migration among different cave chambers occurs to some extent. We investigated if the pattern of genetic differentiation is also reflected in a morphological trait, eye size. Relatively large eyes were found in surface habitats, small eyes in the anterior cave chambers, and the smallest eyes were detected in the innermost cave chamber (XIII). This pattern shows some congruence with a previously proposed morphocline in eye size. However, our data do not support the proposed mechanism for this morphocline, namely that it would be maintained by migration from both directions into the middle cave chambers. This would have led to an increased variance in eye size in the middle cave chambers, which we did not find. Restricted gene flow between the cave and the surface can be explained by local adaptations to extreme environmental conditions, namely H2S and absence of light. Within the cave system, habitat properties are patchy, and genetic differentiation between cave chambers despite migration could indicate local adaptation at an even smaller scale.

Cooperative activation of transcription by autoimmune regulator AIRE and CBP.

Autoimmune regulator (AIRE) is a transcriptional regulator that is believed to control the expression of tissue-specific genes in the thymus. Mutated AIRE is responsible for onset of the hereditary autoimmune disease APECED. AIRE is able to form nuclear bodies (NBs) and interacts with the ubiquitous transcriptional coactivator CBP. In this paper, we show that CBP and AIRE synergistically activate transcription on different promoter reporters whereas AIRE gene mutation R257X, found in APECED patients, interferes with this coactivation effect. Furthermore, the overexpression of AIRE and CBP collaboratively enhance endogenous IFNbeta mRNA expression. The immunohistochemical studies suggest that CBP, depending on the balance of nuclear proteins, is a component of AIRE NBs. We also show that AIRE NBs are devoid of active chromatin and, therefore, not sites of transcription. In addition, we demonstrate by 3D analyses that AIRE and CBP, when colocalizing, are located spatially differently within AIRE NBs. In conclusion, our data suggest that AIRE activates transcription of the target genes, i.e., autoantigens in collaboration with CBP and that this activation occurs outside of AIRE NBs.

Precise measurements of optical cavity dispersion and mirror coating properties via femtosecond combs.

We precisely determine the dispersion of an optical cavity over a large spectral bandwidth using a broadband optical comb generated by a femtosecond laser. This approach permits the effective characterization of the next generation of mirrors that will offer high reflectivity, minimal absorption/scattering loss, and well-defined dispersion characteristics. Such mirrors are essential for constructing passive, high-finesse cavities capable of storing and enhancing ultrashort pulses and for exploring novel intracavity-based experiments in atomic and molecular spectroscopy and extreme nonlinear optics. We characterize both zero and negative group-delay-dispersion mirrors and compare their performance against the targeted coating design. The high sensitivity of this approach is demonstrated with a precise determination of the group-delay dispersion of air inside a 40-cm long optical cavity, demonstrating an accuracy better than 1 fs2.

Nonlinear dynamics inside femtosecond enhancement cavities.

We have investigated the effect of intracavity nonlinear dynamics arising from enhanced peak powers of femtosecond pulses inside broad-bandwidth, dispersion-controlled, high-finesse optical cavities. We find that for chi(3) nonlinearities, when a train of femtosecond pulses are maximally coupled into a cavity by active stabilization of its frequency comb to the corresponding linear resonances of a cavity, enhancement ceases when the peak nonlinear phase shift is sufficient to shift the cavity resonance frequencies by more than a cavity linewidth. In addition, we study and account for the complex spectral dynamics that result from chirping the input pulse and show excellent qualitative agreement with experimental results.

Role of dispersion in multiple-collapse dynamics.

The multiple-collapse dynamics of ultrashort pulses along the propagation direction are investigated under conditions of both normal and anomalous group-velocity dispersion (GVD). In the anomalous-GVD regime we find that collapse events can occur at locations in the medium many diffraction lengths beyond the initial collapse point, in contrast with the normal-GVD regime in which multiple collapse occurs within a diffraction length. Numerical simulations of a modified nonlinear envelope equation are found to be in good qualitative agreement with the observed lengths of the filaments.

Optimal waveguide dimensions for nonlinear interactions.

We investigate strong light confinement in high core-cladding index contrast waveguides with dimensions comparable to and smaller than the wavelength of incident light. We consider oval and rectangular cross sections and demonstrate that an optimal core size exists that maximizes the effective nonlinearity. We also determine that waveguides with asymmetrical cross sections provide the maximum possible nonlinearity, although only a small improvement over the symmetric case. Furthermore, we find that for a specified waveguide shape the largest nonlinearity occurs for nearly the same core area in all cases. Calculations of the dispersion for the optimal-size waveguide at a particular wavelength indicate that the group-velocity dispersion is normal. Ultimately, such designs could be used to develop low-power all-optical devices and to produce waveguides for ultra-low threshold nonlinear frequency generation such as supercontinuum generation.

Self-similar optical wave collapse: observation of the Townes profile.

Analyses of many different types of nonlinear wave equations indicate that a collapsing wave will transform into a universal blowup profile regardless of its initial shape; that is, the amplitude of the wave increases as the spatial extent decreases in a self-similar fashion. We show experimentally that the spatial profile of a collapsing optical wave evolves to a specific circularly symmetric shape, known as the Townes profile, for elliptically shaped or randomly distorted input beams. These results represent the first experimental confirmation of this universal collapsing behavior and provide deeper insight into the high-power filamentation of femtosecond laser pulses in air.

Conical harmonic generation in isotropic materials.

A novel class of nonlinear optical processes is described in which radiation at the nth harmonic is generated through the use of a (2n+1)-order nonlinearity. Utilizing an odd-order nonlinearity, this process allows for the generation and amplification of both odd- and even-order harmonics in isotropic materials. Additionally, this process can always be phase matched in normal-dispersion materials without the use of birefringence. Experimental results are presented in which conical third-harmonic emission is generated from a sapphire sample.

Delivery of nanojoule femtosecond pulses through large-core microstructured fibers.

We investigate femtosecond-pulse propagation through large-core microstructured fibers. Although these fibers are highly multimode, excitation of the fundamental mode is readily achieved, and coupling to higher-order modes is weak even when the fiber is bent or twisted. For prechirped input pulses with energies as large as 3 nJ, pulses as short as 140 fs were produced at the output of the fiber. Such a system could prove to be extremely useful for applications such as in vivo multiphoton microscopy and endoscopy that require delivery of femtosecond pulses and collection of fluorescence.