Low pH constructed Co(ii) and Ni(ii) 1D coordination polymers based on Cα-substituted analogues of zoledronic acid: structural characterization,and spectroscopic and magnetic properties

Three novel coordination compounds based on α,α-disubstituted analogues of zoledronic acid with a cyclopropane (cpp) or cyclobutane (cbt) ring on the C_α carbon, isomorphous [Co(H₂cppZol)(H₂O)]·H₂O (1a), [Ni(H₂cppZol)(H₂O)]·H₂O (1b) and [Co(H₂cbtZol)(H₂O)]·H₂O (2a), were synthesized under hydrothermal conditions at low pH. Single-crystal X-ray diffraction analysis revealed that all the compounds had a 1D double zig–zag chain architecture with an 8 + 8 ring motif formed by alternately arranged symmetrical (–O–P–O–)₂ bridges linking equivalent octahedral metal centres. Both the ligand coordination mode and chain architecture displayed by 1a, 1b and 2a are unique among 1D [M(H₂L)(H₂O)_x]·yH₂O coordination polymers based on nitrogen-containing bisphosphonates reported so far. All the compounds exhibit similar decomposition pathways upon heating with thermal stabilities decreasing in the order 1b > 1a > 2a. The IR spectra revealed that lattice water release above 227, 178 and 97 °C, respectively, does not change the chain architecture leaving them intact up to ca. 320, 280 and 240 °C. Magnetic behaviour investigations indicated that 1a, 2a and 1b exhibit weak alternating antiferromagnetic–ferromagnetic exchange interactions propagated between the magnetic centres through double (–O–P–O–)₂ bridges. The boundary between antiferro- and ferromagnetic couplings for the Co–O⋯O–Co angle in 1a and 2a was estimated to be ca. 80°. This value is also applicable for recently reported [M₃(HL)₂(H₂O)₆]·6H₂O (M = Co, Ni) complexes based on α,α-disubstituted analogues of zoledronic acid and can be used to the explain magnetic behaviour of 1b.

1D Co(ii)/Ni(ii) coordination polymers with alternating antiferromagnetic–ferromagnetic exchange interactions between metal centers propagated through double (–O–P–O–)₂ bridges.     

Diagnostic value of Doppler ultrasound in the assessment of liver cirrhosis in children: Histopathological correlation

We have correlated flow abnormalities in the hepatic vasculature with histological findings in the liver to determine the accuracy of Doppler ultrasound in the diagnosis of liver cirrhosis in children. Eighteen children admitted for evaluation of unknown liver disease were examined prospectively and blindly with Doppler ultrasound prior to liver biopsy. Biopsy specimens showed established cirrhosis in 9 of 18, early cirrhosis in 5 of 18, and no cirrhosis in 4 of 18 children. Doppler studies were also performed on 20 control subjects. The portal vein velocity was decreased (p < 0.0005) and the arterio-portal velocity ratio was increased (p < 0.0005) in the established cirrhosis cohort relative to the controls. For the criteria of the established cirrhosis cohort, the sensitivities of the loss of the reverse flow component in the hepatic veins, the arterio-portal velocity ratio being greater than 3.0, the portal vein velocity being less than 20 cm/s, and the existence of focal flow acceleration in the hepatic veins were 100%, 78%, 67%, and 44%, respectively. The specificity of all of these criteria was 100%. The indicators were not useful in the diagnosis of early cirrhosis. © 1996 John Wiley & Sons, Inc.     

Impact of Surfactant and Calcium Sulfate Type on Air-Entraining Effectiveness in Concrete

The paper presents the evaluation of the influence of calcium sulfate on the air void microstructure in concrete and its action mechanism depending on the character of the air-entraining agent. Gypsum dehydration has been previously proven to negatively influence the air void structure of air-entrained concrete. Ettringite, nucleating from tricalcium aluminate and calcium sulfate, influences the adsorption and mode of action of anionic-based polycarboxylate ether admixtures. The authors suspected the admixture’s air-entraining mechanism was also affected by these characteristics. Gypsum dehydration was confirmed to influence the air void structure. In the case of the anionic surfactant, the content of air bubbles smaller than 300 µm was lower compared to cement with gypsum and hemihydrate. On the other hand, the content of air voids with a diameter up to 60 µm, which are the most favorable, was higher. The results obtained led to the conclusion that the mechanism of air entrainment was twofold, and in most cases occurred through the lowering of surface tension and/or through the adsorption of surfactant on cement grains. The adsorptive mechanism was proved to be more effective in terms of the total air content and the structure of the air void system. The results and conclusions of the study provide guidelines to determine the proper surfactant type to reduce the risk of improper air entrainment of concrete, and emphasize the importance of gypsum dehydration of cement in the process of air entrainment.     

Pyoderma gangrenosum‐like lesions provocated by botulinum injections

Botulinum toxin (BoNT) is a valuable therapeutic tool with several medical indications and the most popular of all cosmetic procedures worldwide. This is the reason for the growing number of unregistered products that may be the reason for adverse reactions. We present a case of a 51‐year‐old woman, who developed a pyoderma gangrenosum‐like reaction at injection sites after the administration of an unregistered BoNT product by a beautician. The clinical course, the morphology of the lesions, the result of histopathological biopsy, and the response to the treatment meets the criteria for diagnosis of pyoderma gangrenosum. The case presented by us is the first adverse reaction of this type after BoNT administration.     

Influence of the Grain Size Distribution of the Limestone Additives on the Color Properties and Phase Composition of Sintered Ceramic Materials Based on Cream-Firing Clays

The study focused on determining color changes in materials made of cream-firing clays from the Opoczno region (Poland) due to the addition of calcium carbonate in the form of limestone. Moreover, the influence of the grain size distribution of this additive on the color properties of the materials and their phase composition was determined. Test samples were prepared using theplastic method and fired at four different temperatures: 1120, 1140, 1160 and 1180 °C. The color properties of the surface of ceramic materials were determined in CIE-Lab color space using a colorimeter. Quantitative phase analysis was performed using the Rietveld method. The research showed that the addition of calcium carbonate causes an increase in the yellow color factor and a decrease in the red color factor and the brightness of the material. Moreover, it was proven that the grain size distribution of the additive used significantly influences the phase composition of the materials, thus determining the values of physical properties and the color of the materials.     

Total expression of HLA-G and TLR-9 in chronic lymphocytic leukemia patients

Suppressed immune status facilitates immune escape mechanisms that allow chronic lymphocytic leukemia cells to proliferate and expand. The expression of HLA-G could effectively inhibit the immune response. In immune response inhibitory signals follow activation of immune system which might be occur during bacterial or viral infection in CLL patients. In the current study we characterized two components of immune system, inhibitory molecule HLA-G with its receptor – CD85j and Toll-like receptor 9.     

The Accuracy of Six Impression Techniques for Osseointegrated Implants

Purpose Six impression techniques were evaluated using tapered and square impression copings. Materials and Methods The absolute distortion was measured using a cast metal impression tray with fiduciary reference points external to the impression material. Measurements of the x, y, z coordinates on the master cast and the impressions were directly made with a travelling digitizing microscope. The difference between the coordinates of each of six sites in the impression and the corresponding reference site were compared. Results There was no significant difference between the techniques for the square copings but that there was a significant loss of accuracy in the z-axis with the tapered copings. Conclusions No significant differences were noted.     

Ueber die künstliche Bildung von Farbstoff im Nervengewebe

Ohne Zusammenfassung Aus dem Cabinet der Klinik des Professors Mirzeewsky. Der psychiatrischen Gesellschaft in St. Petersburg am 28. Januar 1884 mitgetheilt.