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Javier Ruiz

Publications and source records attributed to Javier Ruiz.

At least 19 recordsLinked to original sources
PubMed2006

High structural control in metal-mediated synthesis of new functionalized diphosphines using diphosphinoketenimines as precursors.

The diphosphinoketenimine ligand in the neutral complexes fac-[MnI(CO)(3){(PPh(2))(2)C=C=NR}] (1 a: R = Ph; 1 b: R = p-tolyl) undergoes nucleophilic attack by MeLi and nBuMgCl yielding, after hydrolysis, the diphosphinoenamine-containing complexes fac-[MnI(CO)(3){(PPh(2))(2)C=C(R')NHR}] (3 a,b: R' = Me; 4 a,b: R' = nBu). Complex 1 a reacts under the same conditions with H(2)C=C=CHMgBr to afford fac-[MnI(CO)(3){(PPh(2))(2)C=C(CH(2)CC[triple chemical bond]CH)NHR}] (5 a), which contains a terminal alkyne group on the alpha-carbon atom of the diphosphinoenamine ligand. The cationic complexes fac-[Mn(CO)(4){(PPh(2))(2)C=C=NR}](+) (6) react with H(2)C=C=CHMgBr to afford diphosphinomethanide derivatives bearing three different types of functional groups, depending upon the substituent on the nitrogen atom of the ketenimine: cumulene in fac-[Mn(CO)(4){(PPh(2))(2)C--C(CH=C=CH(2))=N-xylyl}] (7 d), internal alkyne in fac-[Mn(CO)(4){(PPh(2))(2)C--C(C[triple chemical bond]CCH(3))=NtBu}] (8), and quinoline in 9 (R = Ph), whose formation implies an unusual cyclization process. Protonation of 7 d, 8, and 9 with HBF(4) occurs at the nitrogen atom to give the cationic derivatives 10 d, 11, and 12, respectively, which contain the corresponding functionalized diphosphine ligands. Irradiation of 3 a,b and 4 a,b with Vis/UV light makes it possible to isolate the free ligands (PPh(2))(2)C=C(R')NHR (13 a,b and 14 a,b), completing the metal-assisted synthesis of these novel functionalized diphosphines. Irradiation of 12 with Vis/UV light generates free phosphinoquinoline ligand 15, which readily affords a complex 16 containing 15 as a P,N-chelating ligand when treated with [PdCl(2)(NCMe)(2)], thus demonstrating its coordination capability.

Imines↗
PubMed2006

Base induced P-C bond cleavage in a coordinated bis(dimethylphosphino)methane ligand.

Treatment of fac-[Mn(CNR)(CO)3{(PMe2)2CH2}]ClO4 (1a R = Ph, R = tBu) with KOH produced the cleavage of one of the P-C bonds of the coordinated dmpm ligand, resulting in the formation of phosphine-phosphinite complexes fac-[Mn(PMe2O)(CNR)(CO)3(PMe3)] (2a,b). Alkoxides such as NaOMe and NaOEt promoted similar processes in 1a,b, yielding fac-[Mn(CNR)(CO)3(PMe3)(PMe2OR')]ClO4 (3a R = tBu, R' = Me; 3b R = Ph, R' = Me; 4a R = tBu, R' = Et; 4b R = Ph, R' = Et) derivatives. The phosphinite ligand in 2a, b can be sequentially protonated by addition of 0.5 and 1 equivalent of HBF4 leading to fac-[{Mn(CNR)(CO)3(PMe3)(PMe2O)}2H]BF4 (6a,b) and fac-[Mn(CNR)(CO)3(PMe3)(PMe2OH)]BF4 (5a,b), respectively.

Journal Article↗
PubMed2006

Device-associated nosocomial infection rates in intensive care units in four Mexican public hospitals.

BACKGROUND: Routine surveillance of nosocomial infections has become an integral part of infection control and quality assurance in US hospitals. METHODS: As part of the International Nosocomial Infection Control Consortium, we performed a prospective nosocomial infection surveillance cohort study in 5 adult intensive care units of 4 Mexican public hospitals using the Centers for Disease Control and Prevention National Nosocomial Infections Surveillance system definitions. Site-specific nosocomial infection rates were calculated. RESULTS: The overall nosocomial infection rate was 24.4% (257/1055) and 39.0 (257/6590) per 1000 patient days. The most common infection was catheter-associated bloodstream infection, 57.98% (149/257), followed by ventilator-associated pneumonia, 20.23% (52/257), and catheter-associated urinary tract infection, 21.79% (56/257). The overall rate of catheter-associated bloodstream infections was 23.1 per 1000 device-days (149/6450); ventilator-associated pneumonia rate was 21.8 per 1000 device-days (52/2390); and catheter-associated urinary tract infection rate was 13.4 per 1000 device-days (56/4184). CONCLUSION: Our rates are similar to other hospitals of Latin America and higher than US hospitals.

Catheterization, Central Venous↗
PubMed2005

Opposite changes in imidazoline I2 receptors and alpha2-adrenoceptors density in rat frontal cortex after induced gliosis.

Opposite age-dependent changes in alpha2-adrenoceptor and imidazoline I2 receptor (I2-IRs) density have been related to brain gliosis development with aging. To check this hypothesis we applied in rats a model of reactive gliosis induced by heat. The specific binding of [3H]idazoxan (0.5-20 nM) in the presence of (-)adrenaline (5 x 10(-6) M) to membranes from rat brain cortex showed that the density of I(2)-IRs was significantly higher in membranes of injured cortex (Bmax=60+/-6 fmol/mg protein; n=9) than in control (Bmax=38+/-3 fmol/mg protein; n=9; p=0.0053). Conversely, the density of alpha2-adrenoceptors, measured by [3H]clonidine (0.25-16 nM), in the injured cortex (Bmax=75+/-4 fmol/mg protein; n=9) was significantly lower than in sham membranes (Bmax=103+/-7 fmol/mg protein; n=9; p=0.0035). No significant differences in receptor's affinity were observed between both groups. These results support the hypothesis that gliosis induces opposite changes in alpha2-adrenoceptor and I2-IR density.

Actins↗
PubMed2005

The effect of process control on the incidence of central venous catheter-associated bloodstream infections and mortality in intensive care units in Mexico.

PURPOSE: To ascertain the effect of an infection control program including process control on intensive care unit (ICU) rates of intravascular device (IVD)-associated bloodstream infection (BSI). SETTING: Two level III adult ICUs in one public university hospital in Mexico: one medical surgical ICU and one neurosurgical ICU. POPULATION STUDY: All adult patients admitted to study units who had a central venous catheter (CVC) in place for at least 24 hrs. METHODS: A prospective before/after trial in which rates of IVD-associated BSI are determined during a period of active surveillance without process control (phase 1) were compared with rates of IVD-associated BSI after implementing an infection control program applying process control (phase 2). RESULTS: Six hundred five IVD-days were accumulated in phase 1, and 2824 IVD-days were accumulated during phase 2. Compliance with CVC site care and hand hygiene improved significantly from baseline during the study period: placing a gauze dressing over the catheter insertion site (99.24% vs. 86.69%, respectively; relative risk [RR] = 1.14; 95% confidence interval [CI] = 1.07-1.22; p = .0000), proper use of gauze for vascular catheter insertion site (97.87% vs. 84.21%, respectively; RR = 1.16; 95% CI = 1.09-1.24; p = .0000), documentation of the duration of the administration set of the vascular catheter (93.85% vs. 40.69%, respectively; RR = 2.34; 95% CI = 2.14-2.56; p = .0000), and hand hygiene before contact with the patient (84.9% vs. 62%, respectively; RR = 1.37; 95% CI = 1.21-1.51; p = .0000). Overall rates of IVD-associated BSI were lowered significantly from baseline rates after implementation of process control (19.5 vs. 46.3 BSIs per 1000 IVD-days, respectively; RR = 0.42; 95% CI = 0.27-0.66; p = .0001). Overall rates of crude unadjusted mortality were lowered significantly from baseline rates (48.5% vs. 32.8% per 100 discharges, respectively; RR = 0.68; 95% CI = 0.50-0.31; p = .01). CONCLUSION: Implementation of an infection control program utilizing education, process control, and performance feedback was associated with significant reductions in rates of IVD-associated BSI and mortality.

Adult↗
PubMed2004

Turbulence increases the average settling velocity of phytoplankton cells.

It is a well known fact that stirring keeps particles suspended in fluids. This is apparent, for instance, when shaking medicine flasks, when agitating tea deposits in a mug, or when heavy winds fill the air with dust particles. The commonplace nature of such observations makes it easy to accept that this feature will apply to any natural phenomenon as long as the flow is turbulent enough. This has been the case for phytoplankton in the surface mixed layers of lakes and oceans. The traditional view assumes that an increase in turbulence bears ecological advantages for nonmotile groups like diatoms that, otherwise, would settle in deep and unlit waters. However, this assumption has no theoretical ground, and the experimental results we present here point in the opposite direction. Phytoplankton settling velocity increases when turbulence intensifies from the low to the higher values recorded in the upper mixed layers of lakes and oceans. Consequently, turbulence does not favor phytoplankton remaining in lit waters but is rather an environmental stress that can only be avoided through morphological and/or physiological adaptations.

Acoustics↗
PubMed2004

[The role of nursing in the management of a nosocomial infection].

The authors describe what a nosocomial infection is, how frequently it occurs and the main mechanisms through which it spreads. Furthermore, they analyze the importance of systems of epidemic controls bearing in mind the symptoms which indicate a nosocomial infection; the pillars which make up a good health organization in order that this control be effective, and the role which nursing plays inside the team which controls such an infection.

Cross Infection↗
PubMed2003

P-C versus C-H bond cleavage in coordinated bis(dimethylphosphino)methane: controlled access to either phosphinite or functionalized diphosphine complexes.

Treatment of fac-[Mn(CNPh)(CO)3(dmpm)]ClO4 (1) with KOH affords neutral phosphinite complex fac-[Mn(PMe2O)(CNPh)(CO)3(PMe3)] (2) as a result of P-C bond cleavage on the dmpm ligand, whereas when carrying out the reaction in the presence of iodine the diphosphinoketenimine derivative fac-[MnI(CO)3[(PMe2)2C=C=NPh]] (4) is obtained after deprotonation and further functionalization of the central carbon atom of the diphosphine.

Journal Article↗
PubMed2003

Parham-type cycliacylation with Weinreb amides. Application to the synthesis of fused indolizinone systems.

[reaction: see text] Weinreb amides behave as efficient internal electrophiles in Parham-type cycliacylation reactions. Thus, aryl- and heteroaryllithiums generated by lithium-halogen exchange undergo intramolecular cyclization to give fused indolizinone systems as pyrrolo[1,2-b]isoquinolines, thieno[2,3-f]indolizinones, and pyrrolo[1,2-b]acridinones in high yields.

Journal Article↗
PubMed2003

The ocular ischemic syndrome.

The ocular ischemic syndrome represents a serious blinding condition due to retinal ischemia secondary to hemodynamically significant carotid artery stenosis. However, this condition has received little attention in the neurological literature and is likely underdiagnosed. We here describe a patient with bilateral severe carotid stenosis and progressive visual loss due to ocular ischemia. The best management for this condition remains controversial and should be established by including these patients into randomized trials of carotid surgery.

Aged↗
PubMed2003

Possible involvement of a fibroblast growth factor 9 (FGF9)-FGF receptor-3-mediated pathway in adult pig retinal ganglion cell survival in vitro.

The expression and potential roles of fibroblast growth factors (FGF) and their cognate FGF receptors (FGFR) in adult mammalian retinal ganglion cells (RGC) are poorly known. We show that FGFR-3 and FGFR-4 are especially pronounced on RGC and amacrine cell bodies in adult pig inner retinae both in vivo and in vitro. Western blotting revealed distinct profiles for each receptor. Expression of each FGFR and effects of the preferred ligand for FGFR-3, FGF9, upon RGC survival and neurite outgrowth were examined in primary retinal cell cultures: whereas there was no stimulation of neuritogenesis, RGC survival was promoted in a dose-dependent manner (ED(50) approximately 500 pg/ml, mean maximal increase of 60%) and could be completely blocked by addition of FGF9 neutralising antibody. Experiments with three additional FGF (FGF1, FGF2, and FGF4) showed no stimulation of RGC survival above control levels. Taken together, these data suggest that the ligand-receptor couple FGF9-FGFR-3 may function to promote survival of adult mammalian RGC, and their application might be beneficial in retinal degenerative diseases such as glaucoma.

Age Factors↗
PubMed2002

Diphosphanylketenimines: new reagents for the synthesis of unique phosphorus heterocycles.

Two consecutive [3+2] cycloaddition reactions of the diphosphanylketenimine (PPh(2))(2)C[double bond]C[double bond]NPh (3), involving the phosphanyl groups, with two equivalents of the electron-poor alkynes dimethyl acetylenedicarboxylate or methyl acetylenecarboxylate give rise to the formation of the bicyclic 1 lambda(5),3 lambda(5)-diphospholes 5 a,b, which contain a phosphorane unit with five carbon substituents attached to the phosphorus center. Compound 3 undergoes cyclodimerization by crystallization, affording the unsymmetrical dimer 6, which is converted back to 3 by heating in toluene. Compound 6 can be oxidized stepwise on the three trivalent phosphorus atoms by treatment with H(2)O(2) affording 7, 9, and the transient species 10, which are transformed into their corresponding ketenimine monomers either spontaneously (10) or by heating in toluene (7, 9). In this way, the compound (O[double bond]PPh(2))(PPh(2))C[double bond]C[double bond]NPh (8) is quantitatively obtained. Compound 8 readily reacts with the alkynes MeO(2)CC[triple bond]CCO(2)Me and MeO(2)CC[triple bond]CH, and with phenyl isocyanate and ethyl isothiocyanate through regiospecific [3+2] cycloaddition processes furnishing several lambda(5)-phosphole and lambda(5)-azaphosphole derivatives. Finally, the reaction of 8 with N-methylpropargylamine yields the new 2,3-dihydro-1,4-lambda(5)-azaphosphinine 15 through a cycloaddition process involving two functional groups from each molecule.

Journal Article↗