Systematic review found that there was moderate evidence that vaccinating healthcare workers prevented pertussis in infants.

This systematic review investigated the effectiveness of vaccinating healthcare workers against pertussis on the occurrence of nosocomial pertussis outbreaks or infections among unprotected infants. We focused on eight studies, with five different study designs, that involved 39,129 healthy adolescents and adults, 115 healthcare workers, 2000 simulated healthcare workers and a simulated population of 200,000 people. CONCLUSION: There was moderate evidence that tetanus-diphtheria acellular pertussis vaccinations for healthcare workers were effective in preventing pertussis in all age groups and specifically in infants. The results must be interpreted with caution due to the low quality and heterogeneity of the studies.

[Kleine Levin Syndrome: more than just periodic hypersomnia]. / Kleine-Levin-syndroom: meer dan periodieke hypersomnie.

BACKGROUND: Kleine Levin Syndrome (KLS) is a rare disease with periodic hypersomnia as its main feature. Hyperphagia and hypersexuality are also described as classical symptoms, although quite recently it has become clear that the full triad is absent in the majority of patients. CASE DESCRIPTION: A 14-year-old boy developed KLS after a period of flu-like symptoms. Over the course of three years he suffered from seven one-week episodes of extreme hypersomnia (sleeping 18 hours a day), depersonalisation, apathy, anxiety, paranoia, confusion, hallucinations and uninhibited sexual behaviour. He ate little. Ancillary investigations did not reveal any abnormalities. In between these episodes he had no symptoms. CONCLUSION: From this case description and a summary of the symptoms of twelve other patients with KLS, it appears that neuropsychiatric symptoms are much more prominent than hyperphagia and hypersexuality. It is important that the typical KLS phenotype be reappraised, so that the condition can be recognised early and patients managed appropriately.

Heat-killed Staphylococcus aureus reduces atherosclerosis by inducing anti-inflammatory macrophages.

BACKGROUND: Staphylococcus aureus cell wall components can induce IL-10 responses by immune cells, which may be atheroprotective. Therefore, in this study, we investigated whether heat-killed S. aureus (HK-SA) could inhibit the development of atherosclerosis. METHODS: Atherosclerosis-susceptible LDL receptor-deficient mice were administered intraperitoneal HK-SA twice weekly and fed a Western-type diet for 6 weeks. RESULTS: HK-SA administration resulted in a 1.6-fold increase in IL-10 production by peritoneal macrophages and splenocytes, and a 12-fold increase in serum IL-10 levels. Moreover, aortic plaque ICAM-1, VCAM-1 and CCL2 expression levels were significantly downregulated by on average 40%. HK-SA-treated mice had reduced numbers of inflammatory Ly-6C(hi) monocytes as well as Th1 and Th17 cells in the circulation and spleen, respectively. Attenuated leucocyte recruitment resulted in a significant inhibition of macrophage and T cell infiltration in atherosclerotic plaques, culminating in a significant 34% reduction in the development of atherosclerosis. To determine the effects of intraperitoneal HK-SA treatment, we stimulated macrophages with HK-SA in vitro. This resulted in a significant toll-like receptor 2 (TLR2)-dependent increase in IL-10, arginase-1, iNOS, TNF-α, PD-L1, CCL22 and indoleamine 2,3-dioxygenase expression. It was found that phosphoinositide 3-kinase crucially determined the balance of pro- and anti-inflammatory gene expression. The HK-SA-induced macrophage phenotype resembled M2b-like immunoregulatory macrophages. CONCLUSIONS: We have shown that HK-SA treatment induces strong anti-inflammatory IL-10 responses by macrophages, which are largely dependent on TLR2 and PI3K, and protects against the development of atherosclerosis. Commensalism with S. aureus could thus reduce cardiovascular events.

From incommensurate correlations to mesoscopic spin resonance in YbRh2Si2.

Spin fluctuations are reported near the magnetic field-driven quantum critical point in YbRh(2)Si(2). On cooling, ferromagnetic fluctuations evolve into incommensurate correlations located at q(0) = ±(δ,δ), with δ = 0.14 ± 0.04 r.l.u. At low temperatures, an in-plane magnetic field induces a sharp intradoublet resonant excitation at an energy E(0) = gµ(B)µ(0)H with g = 3.8 ± 0.2. The intensity is localized at the zone center, indicating precession of spin density extending ξ = 6 ± 2 Å beyond the 4f site.

A µSR study of the magnetoresistive ruthenocuprates RuSr2Nd(1.8-x)Y0.2Ce(x)Cu2O(10-δ) (x = 0.95 and 0.80).

Zero field muon spin relaxation (ZF-µSR) has been used to study the magnetic properties of the underdoped giant magnetoresistive ruthenocuprates RuSr(2)Nd(1.8-x)Y (0.2)Ce(x)Cu(2)O(10-δ) (x = 0.95, 0.80). The magnetoresistance (MR) is defined so that MR = ((ρ(H)-ρ(0))/ρ(0)) and the giant magnetoresistive ruthenocuprates RuSr(2)Nd(1.8-x)Y(0.2)Ce(x)Cu(2)O(10-δ) exhibit a large reduction in electronic resistivity upon application of a magnetic field. The ZF-µSR results show a gradual loss of initial asymmetry A(0) at the ruthenium spin transition temperature, T(Ru). At the same time the electronic relaxation rate, λ, shows a gradual increase with decreasing temperature below T(Ru). These results have been interpreted as evidence for Cu spin cluster formation below T(Ru). These magnetically ordered clusters grow as the temperature is decreased thus causing the initial asymmetry to decrease slowly. Giant magnetoresistance is observed over a wide temperature range in the materials studied and the magnitude increases as the temperature is reduced from T(Ru) to 4 K which suggests a relation between Cu spin cluster size and |-MR|.

Metallic spin-liquid behavior of the geometrically frustrated Kondo lattice.

Strongly frustrated magnetism of the metallic pyrochlore oxide Pr2Ir2O7 has been revealed by single crystal study. While Pr 4f moments have an antiferromagnetic RKKY interaction energy scale of /T*/ = 20 K mediated by Ir 5d-conduction electrons, no magnetic long-range order is found except for partial spin freezing at 120 mK. Instead, the Kondo effect, including a lnT dependence in the resistivity, emerges and leads to a partial screening of the moments below /T*/. Our results indicate that the underscreened moments show spin-liquid behavior below a renormalized correlation scale of 1.7 K.

Inhomogeneous level splitting in Pr 2-x BixRu2O7.

We report that Bi doping drives Pr 2-x BixRu2O7 from an antiferromagnetic insulator (x = 0) to a metallic paramagnet (x approximately 1) with a broad low T maximum in C/T. Neutron scattering reveals local low energy spin excitations (variant Planck's omega approximately 1 meV) with a spectrum that is unaffected by heating to k(B)T >> variant Planck's omega. We show that a continuous distribution of splittings of the non-Kramers Pr3+ ground-state doublet such as might result from various types of lattice strain can account for all the data.

Monocrystal elastic constants of the negative-thermal-expansion compound zirconium tungstate (ZrW2O8).

We measured zirconium tungstate's elastic constants C(ij). This compound shows relatively soft, nearly isotropic elastic constants with normal Poisson ratios and no approach to Born instability. ZrW2O8 shows normal ambient-temperature elastic constants C(ij), but remarkable dC(ij)/dT that show dominant low-frequency acoustic-vibration modes. From the bulk modulus, we estimated the total ambient-temperature thermodynamic Grüneisen parameter as gamma = -1.2. The dB/dT slope gives a Grüneisen parameter gamma = -7. The 300-0 K bulk-modulus increase (40%) seems unprecedented and breaks Birch's law of corresponding states.

Random fields and the partially paramagnetic state of CsCo0.83Mg0.17Br3: critical scattering study.

We have performed measurements of the critical neutron scattering on CsCo0.83Mg0.17Br3, a dilute stacked triangular lattice (STL) Ising antiferromagnet (AF). A two component line shape associated with the critical fluctuations appears at a temperature coincident with T(N1) observed in pure CsCoBr3. Such scattering is indicative of fluctuations in prototypical random field Ising model (RFIM) systems. The random field domain state arises in this case due to geometrical frustration within the STL Ising AF, which gives rise to a three sublattice Néel state, in which one sublattice is disordered. Magnetic vacancies nucleate AF domains in which the vacancies reside on the disordered sublattice thereby generating a RFIM state in the absence of an applied magnetic field.

Unconventional magnetic correlations in DyB2C and HoB2C.

Layered borocarbides RB2C (R=Dy, Ho, and Er) have been studied by powder neutron diffraction at 2-30 K. ErB2C has two-sublattice antiferromagnetic order below T(N)=16.3 K, but DyB2C and HoB2C show a coexistence of a conventional canted k=(000) ferromagnetic structure and unconventional magnetic correlations. The k=(000) phase orders at T(c)=8.5 K (DyB2C) and 7.1 K (HoB2C), but low-Q diffraction peaks from the unconventional correlations appear above T(c) with different critical temperatures for different peaks: at 8, 10.5, and 15.7 K for HoB2C. This scattering is fitted as diffraction from a Warren-type random magnetic layer lattice and may result from quadrupolar interactions between R3+ spins.

Boron - Carbon Order in CeB(2)C(2).

Powder neutron diffraction studies show that boron and carbon atoms alternate in the planar pi-conjugated layers in CeB(2)C(2) and its lanthanide analogues, rather than being paired as was previously reported. Long and short B-C bonds correspond to the idealized arrangement of single and double bonds shown in the picture.

Molar quantitation of in vivo proton metabolites in human brain with 3D magnetic resonance spectroscopic imaging.

A method for molar quantitation of in vivo proton metabolites in human brain with three-dimensional (3D) proton magnetic resonance spectroscopic imaging (MRSI) is described. The method relies on comparison of brain and calibration phantom measurements, with corrections for coil loading, and spin-lattice and spin-spin relaxation times. A 3D proton MRSI pulse sequence was developed which acquires two echoes and enables acquisition of both the TMS coil loading reference phantom and proton metabolite signals from a single experiment. With the aqueous fraction (tissue water) taken into account, the calculated molar concentrations from 24 centrum semiovale white matter voxels from 4 control subjects were (mmol/l +/- SD): N-acetyl aspartate = 14.6 +/- 2.8, total creatine+phosphocreatine = 6.0 +/- 1.2, total choline = 1.9 +/- 0.4. These values are equivalent to previously reported results obtained from single volume localized proton magnetic resonance spectroscopy.

Use of computer simulations for quantitation of 31P ISIS MRS results.

The difficulties in quantitation of in vivo 31P spectra are exacerbated by the fact that, in general, coils with inhomogeneous B1 fields are used with in vivo samples. A general method for quantitation of in vivo 31P MRS results obtained with the ISIS localization method was developed using computer simulations. The simulation calculates the preparation of the sample magnetization throughout the sample by the ISIS pulse sequence, as well as the sensitivity of signal reception. The calculation accounts for both the B1 field and the B0 gradients applied to the sample. The sensitivity of the experiment is expressed by integration of the simulated signal over the sample, assuming a homogeneous sample. The primary advantage of this approach is that a separate localization experiment on a phantom of known concentration is not required each time parameters of the localization experiment, such as dimensions or location of the localized volume, are altered. In addition, the simulations indicate the degree of contamination (signal from outside of the localized volume) that occurs, and provide a means of comparing different executions of the ISIS experiment. Experiments were performed on phantoms to verify the simulations, and experimental results on human brain and liver are reproduced to show that this approach provides reasonable estimates of metabolite levels in terms of molar concentrations.

Elevated lactate and alkalosis in chronic human brain infarction observed by 1H and 31P MR spectroscopic imaging.

The goal of this study was to investigate lactate and pH distributions in subacutely and chronically infarcted human brains. Magnetic resonance spectroscopic imaging (MRSI) was used to map spatial distributions of 1H and 31P metabolites in 11 nonhemorrhagic subacute to chronic cerebral infarction patients and 11 controls. All six infarcts containing lactate were alkalotic (pHi = 7.20 +/- 0.04 vs. 7.05 +/- 0.01 contralateral, p less than 0.01). This finding of elevated lactate and alkalosis in chronic infarctions does not support the presence of chronic ischemia; however, it is consistent with the presence of phagocytic cells, gliosis, altered buffering mechanisms, and/or luxury perfusion. Total 1H and 31P metabolites were markedly reduced (about 50% on average) in subacute and chronic brain infarctions (p less than 0.01), and N-acetyl aspartate (NAA) was reduced more (approximately 75%) than other metabolites (p less than 0.01). Because NAA is localized in neurons, selective NAA reduction is consistent with pathological findings of a greater loss of neurons than glial cells in chronic infarctions.

Human brain infarction: proton MR spectroscopy.

Two-dimensional proton magnetic resonance (MR) spectroscopic imaging studies were performed of the distributions of the major hydrogen-1 metabolites of choline, creatine, N-acetyl aspartate (NAA) and lactate in normal (n = 6) and subacutely to chronically infarcted (n = 10) human brain. The two dimensions of phase encoding were applied over a 20-mm-thick section of brain tissue that had been selected with a double spin-echo localization method. Normal brain showed bilaterally symmetric metabolite distributions and no detectable lactate. Nine of 10 studies of brain infarction showed substantial decreases in NAA, creatine, and choline in the infarcted area compared with control areas; averaged for all studies, the decreases were 77% +/- 8, 63% +/- 11, and 54% +/- 12, respectively (mean +/- standard error). The decreased metabolite concentrations are probably due primarily to diminished cell density in the infarct. The decrease in NAA was larger than the decreases in choline and creatine. Findings in all of the studies showed lactate in the infarcted tissue and/or ventricles. The continued presence of lactate in the infarct indicates increased anaerobic glycolysis due to ischemia or other factors.

3D phase encoding 1H spectroscopic imaging of human brain.

A three-dimensional (3D) phase-encoding proton spectroscopic imaging method is presented for a whole body MRI/MRS system. Metabolite images at 2 T of choline, creatine, and N-acetyl aspartate (NAA) of normal brain were obtained with a spatial resolution of 1.5 cc. With PRESS volume preselection and outer volume suppression pulses, brain regions close to the skull could be studied without significant contamination by lipid and water signals.

High pressure liquid chromatographic determination with ultraviolet detection of gentamicin and correlation with the microbiological potency.

The content of gentamicin in pharmaceuticals is measured by the high pressure liquid chromatographic technique described in the monographs for Gentamicin Sulphate and Gentamicin Injection in the British Pharmacopoeia 1980 for the determination of the composition of gentamicin. Calculation procedures are presented to transform this qualitative high pressure liquid chromatographic procedure for the assay of gentamicin so that it gives results in terms of potency. A comparison is made of this data with the results of the microbiological assay according to the European Pharmacopoeia.