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1.
Angew Chem Int Ed Engl ; 51(34): 8628-31, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22810960

RESUMO

Double stabilization: Previously unknown polyphosphorus compounds are obtained by activation of white phosphorus (P(4)) coordinated between two CpRu(PPh(3))(2) moieties with iodine, and subsequent hydrolysis. The polyphosphorus compounds (P(4) H(2) I, P(4) H(2), P(3) H(5); see scheme, Cp=cyclopentadienyl) are all stabilized by coordination to two ruthenium centers.

2.
Inorg Chem ; 48(3): 1091-6, 2009 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-19166369

RESUMO

The bimetallic compound [{CpRu(PPh(3))(2)}(2)(mu,eta(1:1)-P(4))][CF(3)SO(3)](2), in which the tetrahedral P(4) is bound to two CpRu(PPh(3))(2) fragments, slowly reacts under mild conditions with a moderate excess of water (1:20) to yield a mixture of compounds. Among the hydrolysis products, the new, remarkably stable complexes [{CpRu(PPh(3))}{CpRu(PPh(3))(2)}{mu(1,4:3),eta(2:1)-P(OH)(2)PHPHPH(OH)}](CF(3)SO(3))(2) (2) and [{CpRu(PPh(3))(2)}{CpRu(PPh(3)){P(OH)(3))}(mu,eta(1:1)-P(2)H(4))](CF(3)SO(3))(2) (3) have been isolated. In the former, the previously unknown 1,1,4-tris(hydroxy)tetraphosphane molecule, P(OH)(2)PHPHPH(OH), is 1,4- and, respectively, 3-coordinated to the CpRu(PPh(3)) and the CpRu(PPh(3))(2) moieties; in the latter, the diphosphane P(2)H(4) is stabilized through coordination to two different metal fragments. All of the compounds were characterized by elemental analyses and IR and NMR spectroscopy. The crystal structure of 2 was determined by X-ray analysis. The formation of the hydroxytetraphosphane, containing the tetraphosphorus entity, provides a clue to the hydrolytic activation of the P(4) molecule.

3.
Nephrol Dial Transplant ; 23(12): 3988-95, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18658176

RESUMO

BACKGROUND: Diabetes mellitus is a common disease, comprising 4-8% of the general population and up to 45% of new dialysis patients in industrialized countries. METHODS: We performed a nationwide study with the aim of analysing the approach of various centres to diabetic patients and to gather data on the epidemiology, clinical characteristics and complications of type 1 and type 2 diabetics. RESULTS: We acquired the data from 513 dialysis centres, 3665 prevalent diabetic patients and 4337 diabetic patients who started dialysis in the previous 10 years. Patient education and dialysis initiation: Sixty percent of the centres educate the patient regarding diet, pharmacological therapy and prevention of diabetic complications; in 245 centres (48%), this task belonged exclusively to the nephrologist and not to a multidisciplinary team. Seventy percent of the centres reported planning the initiation of dialysis and preparing the fistula between 1 and 3 months (78.5%) before the initiation of dialysis. Epidemiological and clinical data: Diabetic patients (56.9% males) represented 12.5% of the total dialysis population in Italy. The ratio between diabetes type 2 and type 1 was 5.3. The initial treatment was haemodialysis (HD) in 2533 patients (bicarbonate HD 88.8%) and peritoneal dialysis (PD) in 405 patients (CAPD 82.2%). During their dialytic life, 383 patients (226 from HD and 157 from PD) changed treatment modality, mainly because of cardiocirculatory instability (158 cases) or infection of the catheter tunnel/peritoneum (89 cases). The changes were mainly directed from bicarbonate HD and CAPD towards diffusive-convective extracorporeal techniques. Blood glucose (mean 154 +/- 56.8 mg/dl) exceeded 200 mg/dl in 15.2% of patients; serum cholesterol was >200 mg/dl in 39.3% of patients; serum triglycerides exceeded 200 mg/dl in 39.2% of patients and mean values for glycosylated haemoglobin was 7.2 +/- 1.8%. The nutritional state was judged to be normal in 59.6% of patients, 16.2% appeared to be mildly malnourished and 3% severely malnourished; 21.1% of subjects were obese. Echocardiography showed left ventricular hypertrophy in 90% of patients and echocolordoppler examination of the great vessels showed pathological findings (plaques and stenoses) in 73%. Pharmacological therapy. Sixty-nine percent of patients were treated with antihypertensive drugs, mainly calcium antagonists (50%) and ACE inhibitors (27%). Nitrates were prescribed for 33% of patients; antiplatelet or anticoagulant drugs were prescribed for 37% of patients. CONCLUSIONS: The present study demonstrates that the prevalence of diabetics in dialysis continues to increase in Italy, but remains less than that in Northern European countries. Type 2 diabetes is as dangerous as type 1 in terms of serious complications. There appears to be a greater awareness on the part of nephrologists of the serious problems associated with the care of diabetic patients in dialysis. The ideal dialytic modality has not been determined, dialysis is often not initiated in a timely manner and optimal drug therapy is not always prescribed. The aspirations to treat the diabetic dialysis patient according to currently accepted best practice guidelines still need to be fully realized.


Assuntos
Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/terapia , Diálise Renal/estatística & dados numéricos , Idoso , Anti-Hipertensivos/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Nefropatias Diabéticas/sangue , Nefropatias Diabéticas/complicações , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Diálise Renal/efeitos adversos , Diálise Renal/métodos , Inquéritos e Questionários
5.
Chemistry ; 13(23): 6682-90, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17508375

RESUMO

The reaction of [CpRu(PPh(3))(2)Cl] (1) with half an equivalent of P(4) or P(4)S(3) in the presence of AgCF(3)SO(3) as chloride scavenger affords the stable dimetal complexes [{CpRu(PPh(3))(2)}(2)(micro,eta(1:1)-P(4))][CF(3)SO(3)](2).3 CH(2)Cl(2) (2) and [{CpRu(PPh(3))(2)}(2)(micro,eta(1:1)-P(apical)-P(basal)-P(4)S(3))][CF(3)SO(3)](2).0.5 C(7)H(8) (3), in which the tetrahedral P(4) and mixed-cage P(4)S(3) molecules are respectively bound to two CpRu(PPh(3))(2) fragments through two phosphorus atoms. The coordinated cage molecules, at variance with the free ligands, readily react with an excess of water in THF under mild conditions. Among the hydrolysis products, the new, remarkably stable complexes [{CpRu(PPh(3))(2)}(2)(micro,eta(1:1)-P(2)H(4))][CF(3)SO(3)](2) (4) and [CpRu(PPh(3))(2)(eta(1)-PH(2)SH)]CF(3)SO(3) (8) were isolated. In the former, diphosphane, P(2)H(4), is coordinated to two CpRu(PPh(3))(2) fragments, and in the latter thiophosphinous acid, H(2)PSH, is coordinated to the metal centre through the phosphorus atom. All compounds were characterised by elemental analyses and IR and NMR spectroscopy. The crystal structures of 2, 3, 4 and 8 were determined by X-ray diffraction.

6.
Dalton Trans ; (2): 389-95, 2006 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-16365654

RESUMO

Treatment of [CpRu(PPh(3))(2)Cl] 1 with the stoichiometric amount of H(3)PO(2) or H(3)PO(3) in the presence of chloride scavengers (AgCF(3)SO(3) or TlPF(6)) yields compounds of formula [CpRu(PPh(3))(2)(HP(OH)(2))]Y (Y = CF(3)SO(3) 2a or PF(6) 2b) and [CpRu(PPh(3))(2)(P(OH)(3))]Y (Y = CF(3)SO(3) 3aor PF(6) 3b) which contain, respectively, the HP(OH)(2) and P(OH)(3) tautomers of hypophosphorous and phosphorous acids bound to ruthenium through the phosphorus atom. The triflate derivatives 2a and 3a react further with hypophosphorous or phosphorous acids to yield, respectively, the complexes [CpRu(PPh(3))(HP(OH)(2))(2)]CF(3)SO(3) 4 and [CpRu(PPh(3))(P(OH)(3))(2)]CF(3)SO(3) 5 which are formed by substitution of one molecule of the acid for a coordinated triphenylphosphine molecule. The compounds 2 and 3 are quite stable in the solid state and in solutions of common organic solvents, but the hexafluorophosphate derivatives undergo easy transformations in CH(2)Cl(2): the hypophosphorous acid complex 2b yields the compound [CpRu(PPh(3))(2)(HP(OH)(2))]PF(2)O(2) 6, whose difluorophosphate anion originates from hydrolysis of PF(6)(-); the phosphorous acid complex 3b yields the compound [CpRu(PPh(3))(2)(PF(OH)(2))]PF(2)O(2) 7, which is produced by hydrolysis of hexafluorophosphate and substitution of a fluorine for an OH group of the coordinated acid molecule. All the compounds have been characterized by elemental analyses and NMR measurements. The crystal structures of 2a, 3a and 7 have been determined by X-ray diffraction methods.

7.
Dalton Trans ; (13): 2234-6, 2005 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-15962041

RESUMO

The P4 molecule bound to ruthenium as an eta1-ligand in [CpRu(PPh3)2(eta1-P4)]Y (Y = PF6, CF3SO3) undergoes an easy reaction with water in exceedingly mild conditions to yield PH3, which remains coordinated to the [CpRu(PPh3)2] fragment, and oxygenated derivatives.

8.
Ann Chim ; 94(4): 281-93, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15242093

RESUMO

This study reports the characterization of n-alkanes and PAHs in 13 PM10 samples collected in the South area of Prato (Italy) during the period April-July 2002. n-Alkanes concentrations ranged between 9.45 and 182.64 ng/mc while PAHs concentrations ranged from 3.058 to 22.048 ng/mc. No correlation was evidenced between benzo(a)pirene and PM10 concentrations. Total carbonaceous aerosol was also measured and it meanly accounted for 21.5% of the PM10 mass ranging from 12.4% to 27.1%.


Assuntos
Poluentes Atmosféricos/análise , Alcanos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Itália , Tamanho da Partícula , Estações do Ano
9.
J Nephrol ; 15(5): 593-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12455729

RESUMO

We report the case of a 52 year-old woman who was re-admitted to regular hemodialysis treatment because of chronic rejection of a renal transplant. She had received her mother's kidney 17 years before and had been treated for a long time with steroids, cyclosporin and azathioprine. In the last two months, fever had occurred, and persisted with the start of hemodialysis. She was admitted to our nephrology unit. Clinical, laboratory, radiological and endoscopic investigations did not lead to a precise diagnosis and broad-spectrum antimicrobial therapy failed. Some days later, a clear clinical picture of acute abdomen arose and at laparatomy a perforated jejunal ulcer was found. Histological investigation revealed caseous necrosis around the ulcer. Ziehl-Neelsen (ZN) stain showed a number of acid-fast resistant bacilli. Polymerase chain reaction (PCR) confirmed the presence of Mycobacterium tuberculosis. Specific therapy was started, but nevertheless the patient died a few days later, of septic shock. Our case shows that tuberculosis continues to be a significant, severe clinical problem in transplant recipients and is in fact still an important cause of death in these patients. The possibility of tuberculosis must be taken into account when a transplant patient shows fever and severe abdominal trouble with no clear evidence of another infection.


Assuntos
Transplante de Rim/efeitos adversos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Gastrointestinal/diagnóstico , Antituberculosos/administração & dosagem , DNA Bacteriano/análise , Progressão da Doença , Eletroforese em Gel de Ágar , Evolução Fatal , Feminino , Rejeição de Enxerto/terapia , Humanos , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Diálise Renal , Tuberculose Gastrointestinal/tratamento farmacológico
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