Highly recyclable Ti0.97Ni0.03O1.97 catalyst coated on cordierite monolith for efficient transformation of arylboronic acids to phenols and reduction of 4-nitrophenol.

A stable Ni2+ substituted TiO2 catalyst (Ti0.97Ni0.03O1.97) has been synthesized by a solution combustion method with an average crystallite size of 7.5 nm. Ti1-xNixO2-x (x = 0.01-0.06) crystallizes in the TiO2 anatase structure with Ni2+ substituted in Ti4+ ion sites and Ni taking a nearly square planar geometry. This catalyst is found to be highly active in the transformation of diverse arylboronic acids to the corresponding phenols. The catalyst coated cordierite monolith can even be recycled for up to 20 cycles with a cumulative TOF of 1.8 × 105 h-1. In scale-up reactions, various phenols are synthesized by employing a single cordierite monolith. It also shows high performance in the reduction of 4-nitrophenol.

Microengineered cell and tissue systems for drug screening and toxicology applications: Evolution of in-vitro liver technologies.

The liver performs many key functions, the most prominent of which is serving as the metabolic hub of the body. For this reason, the liver is the focal point of many investigations aimed at understanding an organism's toxicological response to endogenous and exogenous challenges. Because so many drug failures have involved direct liver toxicity or other organ toxicity from liver generated metabolites, the pharmaceutical industry has constantly sought superior, predictive in-vitro models that can more quickly and efficiently identify problematic drug candidates before they incur major development costs, and certainly before they are released to the public. In this broad review, we present a survey and critical comparison of in-vitro liver technologies along a broad spectrum, but focus on the current renewed push to develop "organs-on-a-chip". One prominent set of conclusions from this review is that while a large body of recent work has steered the field towards an ever more comprehensive understanding of what is needed, the field remains in great need of several key advances, including establishment of standard characterization methods, enhanced technologies that mimic the in-vivo cellular environment, and better computational approaches to bridge the gap between the in-vitro and in-vivo results.

Limb girdle weakness responding to salbutamol: an Indian family with DOK7 mutation.

BACKGROUND: Congenital Myasthenic Syndromes (CMS) are heterogeneous genetic diseases. CASE CHARACTERISTICS: Two siblings presented with progressive limb girdle weakness without significant fluctuations or ocular muscle weakness. Repetitive nerve stimulation showed a decremental response and there was no response to pyridostigmine therapy. OUTCOME: A trial of salbutamol produced a remarkable, consistent improvement. Mutation in exon 5 of the DOK7 gene was found in both siblings. MESSAGE: Patients with congenital myasthenic syndrome with DOK 7 mutation benefit remarkably with salbutamol.

Validation of the TRMM Multi Satellite Rainfall Product 3B42 and estimation of scavenging coefficients for (131)I and (137)Cs using TRMM 3B42 rainfall data.

The TRMM rainfall product 3B42 is compared with rain gauge observations for Kaiga, India on monthly and seasonal time scales. This comparison is carried out for the years 2004-2007 spanning four monsoon seasons. A good correlation is obtained between the two data sets however; magnitude wise, the cumulative precipitation of the satellite product on monthly and seasonal time scales is deficient by almost 33-40% as compared to the rain gauge data. The satellite product is also compared with APHRODITE's Monsoon Asia data set on the same time scales. This comparison indicates a much better agreement since both these data sets represent an average precipitation over the same area. The scavenging coefficients for (131)I and (137)Cs are estimated using TRMM 3B42, rain gauge and APHRODITE data. The values obtained using TRMM 3B42 rainfall data compare very well with those obtained using rain gauge and APHRODITE data.

Molecular testing of 163 patients with Morquio A (Mucopolysaccharidosis IVA) identifies 39 novel GALNS mutations.

Morquio A (Mucopolysaccharidosis IVA; MPS IVA) is an autosomal recessive lysosomal storage disorder caused by partial or total deficiency of the enzyme galactosamine-6-sulfate sulfatase (GALNS; also known as N-acetylgalactosamine-6-sulfate sulfatase) encoded by the GALNS gene. Patients who inherit two mutated GALNS gene alleles have a decreased ability to degrade the glycosaminoglycans (GAGs) keratan sulfate and chondroitin 6-sulfate, thereby causing GAG accumulation within lysosomes and consequently pleiotropic disease. GALNS mutations occur throughout the gene and many mutations are identified only in single patients or families, causing difficulties both in mutation detection and interpretation. In this study, molecular analysis of 163 patients with Morquio A identified 99 unique mutations in the GALNS gene believed to negatively impact GALNS protein function, of which 39 are previously unpublished, together with 26 single-nucleotide polymorphisms. Recommendations for the molecular testing of patients, clear reporting of sequence findings, and interpretation of sequencing data are provided.

Biochemical indicators of dental caries in saliva: an in vivo study.

This study evaluated the superoxide dismutase (SOD) activity, copper and zinc levels in saliva of caries-active and caries-free individuals. Eighty healthy adults were divided according to WHO criteria: caries-free (DMFT = 0) and caries-active (DMFT >10). Saliva collected was estimated for SOD activity as well as copper and zinc levels using the atomic nitro blue tetrazolium chloride reduction method and absorption spectrophotometry, respectively. The Student t test was applied. In conclusion, SOD activity as well as copper and zinc levels increased in the caries-active group and showed statistically significant results.

Acute pulmonary embolism being the first presentation of undetected HIV infection: report of two cases.

Though HIV infection is considered as a hypercoagulable state, but occurrence of acute pulmonary embolism (PE) is rare and usually seen in the advanced stage of the disease. PE as a presentation in a case where there is no previous history of having HIV infection is very rare; a Medline search revealed only one case reported previously. We describe two cases who presented with acute PE and were treated; they were subsequently diagnosed as having HIV infection.

Hepatoprotective potential of ether insoluble phenolic components of n-butanol fraction (EPC-BF) of flaxseed against CCl(4) -induced liver damage in rats.

OBJECTIVE: to investigate the hepatoprotective potential of ether insoluble phenolic components of n-butanol fraction (EPC-BF) of flaxseed against CCl(4) -induced liver damage in rats. MATERIALS AND METHODS: Hepatotoxicity was induced to Wistar rats by administration of 0.2% CCl(4) in olive oil (8 mL/kg, i.p.) on the seventh day of treatment. Hepatoprotective potential of EPC-BF at doses, 250 and 500 mg/kg, p.o. was assessed through biochemical and histological parameters. RESULTS: EPC-BF and silymarin pretreated animal groups showed significantly decreased activities of Aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and level of total bilirubin, elevated by CCl(4) intoxication. Hepatic lipid peroxidation elevated by CCl(4) intoxication were also found to be alleviated at almost normal level in the EPC-BF and silymarin pretreated groups. Histological studies supported the biochemical findings and treatment of EPC-BF at doses 250 and 500 mg/kg, p.o. was found to be effective in restoring CCl(4) -induced hepatic damage. However, EPC-BF did not show dose-dependent hepatoprotective potential. EPC-BF depicted maximum protection against CCl(4) -induced hepatic damage at lower dose 250 mg/kg than higher dose (500 mg/ kg). CONCLUSION: EPC-BF possesses the significant hepatoprotective activity against CCl(4) induced liver damage, which could be mediated through increase in antioxidant defenses.

In vitro anti-metastatic activity of enterolactone, a mammalian lignan derived from flax lignan, and down-regulation of matrix metalloproteinases in MCF-7 and MDA MB 231 cell lines.

BACKGROUND: Actin cytoskeleton is involved in actin-based cell adhesion, cell motility, and matrix metalloproteinases(MMPs) MMP2, MMP9, MMP11 and MMP14 are responsible for cell invasion in breast cancer metastasis. The dietary intake of lignan from flax seed gets converted to enterolactone (EL) and enterodiol in the human system. Here we show that the enterolactone has a very significant anti-metastatic activity as demonstrated by its ability to inhibit adhesion and invasion and migration in MCF-7 and MDA MB231 cell lines. MATERIALS AND METHODS: Migration inhibition assay, actin-based cell motility assay along with reverse transcriptase polymerase chain reaction (RT-PCR) for MMP2, MMP9, MMP11 and MMP14 genes were performed in MCF-7 and MDA MB 231 cell lines. RESULTS: Enterolactone seems to inhibit actin-based cell motility as evidenced by confocal imaging and photo documentation of cell migration assay. The results are supported by the observation that the enterolactone in vitro significantly down-regulates the metastasis-related metalloproteinases MMP2, MMP9 and MMP14 gene expressions. No significant alteration in the MMP11 gene expression was found. CONCLUSIONS: Therefore we suggest that the anti-metastatic activity of EL is attributed to its ability to inhibit cell adhesion, cell invasion and cell motility. EL affects normal filopodia and lamellipodia structures, polymerization of actin filaments at their leading edges and thereby inhibits actin-based cell adhesion and cell motility. The process involves multiple force-generating mechanisms of actin filaments i.e. protrusion, traction, deadhesion and tail-retraction. By down-regulating the metastasis-related MMP2, MMP9 and MMP14 gene expressions, EL may be responsible for cell invasion step of metastasis.

Isolation rearing significantly perturbs brain metabolism in the thalamus and hippocampus.

Psychosocial neglect during childhood severely impairs both behavioral and physical health. The isolation rearing model in rodents has been employed by our group and others to study this clinical problem at a basic level. We previously showed that immediate early gene (IEG) expression in the hippocampus and medial prefrontal cortex (mPFC) is decreased in isolation-reared (IR) compared to group-reared (GR) rats. In the current study, we sought to evaluate: (1) whether these changes in IEG expression would be detected by the measurement of brain glucose metabolism using positron emission tomography (PET) with fluorodeoxyglucose (FDG) and (2) whether PET FDG could illuminate other brain regions with different glucose metabolism in IR compared to GR rats. We found that there were significant differences in FDG uptake in the hippocampus that were consistent with our findings for IEG expression (decreased mean FDG uptake in IR rats). In contrast, in the mPFC, the FDG uptake between IR and GR rats did not differ. Finally, we found decreased mean FDG uptake in the thalamus of the IR rats, a region we had not previously examined. The results suggest that PET FDG has the potential to be utilized as a biomarker of molecular changes in the hippocampus. Further, the differences found in thalamic brain FDG uptake suggest that further investigation of this region at the molecular and cellular levels may provide an important insight into the neurobiological basis of the adverse clinical outcomes found in children exposed to psychosocial deprivation.

Combined orthodontic and surgical correction of an adolescent patient with thin palatal cortex and vertical maxillary excess.

This paper describes the treatment of a male patient aged 14 years who presented with a skeletal class I, vertical maxillary excess, marked increase in overjet, thin palatal cortex and a gummy smile. Considering the severity of his malocclusion and its impact severity on his psychosocial well being, he was managed with a combined approach of Fixed Orthodontic therapy and Orthognathic surgery, even though his growth was not complete. Records of Pre treatment, Post treatment and three years in retention were analyzed and the functional and esthetic results were found to be fairly stable.

Direct evidence of redox interaction between metal ion and support oxide in Ce(0.98)Pd(0.02)O(2-δ) by a combined electrochemical and XPS study.

A combined electrochemical method and X-ray photo electron spectroscopy (XPS) has been utilized to understand the Pd(2+)/CeO(2) interaction in Ce(1-x)Pd(x)O(2-δ) (x = 0.02). A constant positive potential (chronoamperometry) is applied to Ce(0.98)Pd(0.02)O(2-δ) working electrode which causes Ce(4+) to reduce to Ce(3+) to the extent of ~35%, while Pd remains in the +2 oxidation state. Electrochemically cycling this electrode between 0.0-1.2 V reverts back to the original state of the catalyst. This reversibility is attributed to the reversible reduction of Ce(4+) to Ce(3+) state. CeO(2) electrode with no metal component reduces to CeO(2-y) (y~0.4) after applying 1.2 V which is not reversible and the original composition of CeO(2) cannot be brought back in any electrochemical condition. During the electro-catalytic oxygen evolution reaction at a constant 1.2 V for 1000 s, Ce(0.98)Pd(0.02)O(2-δ) reaches a steady state composition with Pd in the +2 states and Ce(4+): Ce(3+) in the ratio of 0.65:0.35. This composition can be denoted as Ce(4+)(0.63)Ce(3+)(0.35)Pd(0.02)O(2-δ-y) (y~0.17). When pure CeO(2) is put under similar electrochemical condition, it never reaches the steady state composition and reduces almost to 85%. Thus, Ce(0.98)Pd(0.02)O(2-δ) forms a stable electrode for the electro-oxidation of H(2)O to O(2) unlike CeO(2) due to the metal support interaction.

Sonochemical synthesis of Ce(1-x)Fe(x)O(2-δ) (0 ≤ x ≤ 0.45) and Ce(0.65)Fe(0.33)Pd(0.02)O(2-δ) nanocrystallites: oxygen storage material, CO oxidation and water gas shift catalyst.

Nanocrystalline Ce(1-x)Fe(x)O(2-δ) (0 ≤ x ≤ 0.45) and Ce(0.65)Fe(0.33)Pd(0.02)O(2-δ) of ~4 nm sizes were synthesized by a sonochemical method using diethyletriamine (DETA) as a complexing agent. Compounds were characterized by powder X-ray diffraction (XRD), X-ray photo-electron spectroscopy (XPS) and transmission electron microscopy (TEM). Ce(1-x)Fe(x)O(2-δ) (0 ≤ x ≤ 0.45) and Ce(0.65)Fe(0.33)Pd(0.02)O(2-δ) crystallize in fluorite structure where Fe is in +3, Ce is in +4 and Pd is in +2 oxidation state. Due to substitution of smaller Fe(3+) ion in CeO(2), lattice oxygen is activated and 33% Fe substituted CeO(2)i.e. Ce(0.67)Fe(0.33)O(1.835) reversibly releases 0.31[O] up to 600 °C which is higher or comparable to the oxygen storage capacity of CeO(2)-ZrO(2) based solid solutions (Catal. Today 2002, 74, 225-234). Due to interaction of redox potentials of Pd(2+/0)(0.89 V) and Fe(3+/2+) (0.77 V) with Ce(4+/3+) (1.61 V), Pd ion accelerates the electron transfer from Fe(2+) to Ce(4+) in Ce(0.65)Fe(0.33)Pd(0.02)O(1.815), making it a high oxygen storage material as well as a highly active catalyst for CO oxidation and water gas shift reaction. The activation energy for CO oxidation with Ce(0.65)Fe(0.33)Pd(0.02)O(1.815) is found to be as low as 38 kJ mol(-1). Ce(0.67)Fe(0.33)O(1.835) and Ce(0.65)Fe(0.33)Pd(0.02)O(1.815) have also shown high activity for the water gas shift reaction. CO conversion to CO(2) is 100% H(2) specific with these catalysts and conversion rate was found to be as high 27.2 µmoles g(-1) s(-1) and the activation energy was found to be 46.4 kJ mol(-1) for Ce(0.65)Fe(0.33)Pd(0.02)O(1.815).

Structure of Ce(1-x)Sn(x)O(2) and its relation to oxygen storage property from first-principles analysis.

CeO(2)-SnO(2) solid solution has been reported to possess high oxygen storage/release property which possibly originates from local structural distortion. We have performed first-principles based density functional calculations of Ce(1-x)Sn(x)O(2) structure (x=0, 0.25, 0.5, 1) to understand its structural stability in fluorite in comparison to rutile structure of the other end-member SnO(2), and studied the local structural distortion induced by the dopant Sn ion. Analysis of relative energies of fluorite and rutile phases of CeO(2), SnO(2), and Ce(1-x)Sn(x)O(2) indicates that fluorite structure is the most stable for Ce(1-x)Sn(x)O(2) solid solution. An analysis of local structural distortions reflected in phonon dispersion show that SnO(2) in fluorite structure is highly unstable while CeO(2) in rutile structure is only weakly unstable. Thus, Sn in Ce(1-x)Sn(x)O(2)-fluorite structure is associated with high local structural distortion whereas Ce in Ce(1-x)Sn(x)O(2)-rutile structure, if formed, will show only marginal local distortion. Determination of M-O (M=Ce or Sn) bond lengths and analysis of Born effective charges for the optimized structure of Ce(1-x)Sn(x)O(2) show that local coordination of these cations changes from ideal eightfold coordination expected of fluorite lattice to 4+4 coordination, leading to generation of long and short Ce-O and Sn-O bonds in the doped structure. Bond valence analyses for all ions show the presence of oxygen with bond valence approximately 1.84. These weakly bonded oxygen ions are relevant for enhanced oxygen storage/release properties observed in Ce(1-x)Sn(x)O(2) solid solution.

Noble metal ionic catalysts.

Because of growing environmental concerns and increasingly stringent regulations governing auto emissions, new more efficient exhaust catalysts are needed to reduce the amount of pollutants released from internal combustion engines. To accomplish this goal, the major pollutants in exhaust-CO, NO(x), and unburned hydrocarbons-need to be fully converted to CO(2), N(2), and H(2)O. Most exhaust catalysts contain nanocrystalline noble metals (Pt, Pd, Rh) dispersed on oxide supports such as Al(2)O(3) or SiO(2) promoted by CeO(2). However, in conventional catalysts, only the surface atoms of the noble metal particles serve as adsorption sites, and even in 4-6 nm metal particles, only 1/4 to 1/5 of the total noble metal atoms are utilized for catalytic conversion. The complete dispersion of noble metals can be achieved only as ions within an oxide support. In this Account, we describe a novel solution to this dispersion problem: a new solution combustion method for synthesizing dispersed noble metal ionic catalysts. We have synthesized nanocrystalline, single-phase Ce(1-x)M(x)O(2-delta) and Ce(1-x-y)Ti(y)M(x)O(2-delta) (M = Pt, Pd, Rh; x = 0.01-0.02, delta approximately x, y = 0.15-0.25) oxides in fluorite structure. In these oxide catalysts, Pt(2+), Pd(2+), or Rh(3+) ions are substituted only to the extent of 1-2% of Ce(4+) ion. Lower-valent noble metal ion substitution in CeO(2) creates oxygen vacancies. Reducing molecules (CO, H(2), NH(3)) are adsorbed onto electron-deficient noble metal ions, while oxidizing (O(2), NO) molecules are absorbed onto electron-rich oxide ion vacancy sites. The rates of CO and hydrocarbon oxidation and NO(x) reduction (with >80% N(2) selectivity) are 15-30 times higher in the presence of these ionic catalysts than when the same amount of noble metal loaded on an oxide support is used. Catalysts with palladium ion dispersed in CeO(2) or Ce(1-x)Ti(x)O(2) were far superior to Pt or Rh ionic catalysts. Therefore, we have demonstrated that the more expensive Pt and Rh metals are not necessary in exhaust catalysts. We have also grown these nanocrystalline ionic catalysts on ceramic cordierite and have reproduced the results we observed in powder material on the honeycomb catalytic converter. Oxygen in a CeO(2) lattice is activated by the substitution of Ti ion, as well as noble metal ions. Because this substitution creates longer Ti-O and M-O bonds relative to the average Ce-O bond within the lattice, the materials facilitate high oxygen storage and release. The interaction among M(0)/M(n+), Ce(4+)/Ce(3+), and Ti(4+)/Ti(3+) redox couples leads to the promoting action of CeO(2), activation of lattice oxygen and high oxygen storage capacity, metal support interaction, and high rates of catalytic activity in exhaust catalysis.

Pt metal-CeO2 interaction: direct observation of redox coupling between Pt0/Pt2+/Pt4+ and Ce4+/Ce3+ states in Ce(0.98)Pt(0.02)O2-delta catalyst by a combined electrochemical and x-ray photoelectron spectroscopy study.

Pt ions-CeO(2) interaction in Ce(1-x)Pt(x)O(2-delta) (x=0.02) has been studied for the first time by electrochemical method combined with x-ray diffraction and x-ray photoelectron spectroscopy. Working electrodes made of CeO(2) and Ce(0.98)Pt(0.02)O(2-delta) mixed with 30% carbon are treated electrochemically between 0.0-1.2 V in potentiostatic (chronoamperometry) and potentiodynamic (cyclic voltametry) mode with reference to saturated calomel electrode. Reversible oxidation of Pt(0) to Pt(2+) and Pt(4+) state due to the applied positive potential is coupled to simultaneous reversible reduction of Ce(4+) to Ce(3+) state. CeO(2) reduces to CeO(2-y) (y=0.35) after applying 1.2 V, which is not reversible; Ce(0.98)Pt(0.02)O(2-delta) reaches a steady state with Pt(2+):Pt(4+) in the ratio of 0.60:0.40 and Ce(4+):Ce(3+) in the ratio of 0.55:0.45 giving a composition Ce(0.98)Pt(0.02)O(1.74) at 1.2 V, which is reversible. Composition of Pt ion substituted compound is reversible between Ce(0.98)Pt(0.02)O(1.95) to Ce(0.98)Pt(0.02)O(1.74) within the potential range of 0.0-1.2 V. Thus, Ce(0.98)Pt(0.02)O(2-delta) forms a stable electrode for oxidation of H(2)O to O(2) unlike CeO(2). A linear relation between oxidation of Pt(2+) to Pt(4+) with simultaneous reduction in Ce(4+) to Ce(3+) is observed demonstrating Pt-CeO(2) metal support interaction is due to reversible Pt(0)/Pt(2+)/Pt(4+) interaction with Ce(4+)/Ce(3+) redox couple.

Noble metal ionic catalysts: correlation of increase in CO oxidation activity with increasing effective charge on Pd ion in Pd ion substituted Ce1-xMxO2-delta (M = Ti, Zr and Hf).

Pd ion substituted Ce1-xMxO2-delta (M = Ti, Zr, Hf) have been prepared by a single step solution combustion method. Two atom% Pd ion substitution in the title compounds is confirmed by X-ray diffraction (XRD) and Pd ion charge state and redox properties have been determined by X-ray photoelectron spectroscopy (XPS) and H2/TPR studies. While Pd ion in CeO2 (Ce0.98Pd0.02O2-delta) showed higher catalytic activity for CO oxidation than Pd metal impregnated over CeO2, further increase in the catalytic activity is observed with Pd ion in Ce1-xTi(Hf)xO2 and a decrease in the activity with Pd ion in Ce1-xZrxO2. Effective charge on Pd ion could be varied by its substitution in these solid solutions Ce1-xMxO2 (M = Ti, Zr & Hf) and also in TiO2 compared to Pd ion in PdO. Effective positive charge on Pd ion is determined from the core level binding energy shift of Pd(3d5/2) peak with respect to Pd metal. Rate of CO oxidation increased and activation energy decreased with increase in effective charge on the Pd ion in the Pd ion substituted fluorites.

Melioidosis and tuberculosis: dual pathogens in a neck abscess.

INTRODUCTION: Melioidosis is an infectious disease caused by a saprophytic bacterium, Burkholderia pseudomallei. It is endemic to Southeast Asia and Northern Australia. It may manifest as a pulmonary lesion, osteomyelitis, abscesses in soft tissue and various organs, or as septicaemia. CASE REPORT: We report a case of a 40-year-old, diabetic man who presented with a neck lump resulting from super-infection of a tuberculosis cavity with B pseudomallei. The patient was successfully managed by drainage along with meticulous excision of the capsule and prolonged antibiotic and anti-tubercular treatment. DISCUSSION: Melioidosis may be confused diagnostically with tuberculosis, as both diseases are endemic in the same regions. Our patient was unfortunate to suffer from both endemic diseases simultaneously, perhaps representing the first such case in the world literature. CONCLUSION: Increased awareness of melioidosis is important as, although the organism is easy to culture, it may be dismissed as a contaminant.