5 research outputs found

    Synthesis and characterization of η5-cyclopentadienyl-silylallyl niobium and tantalum complexes

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    Reaction of the disilylcyclopentadiene 1,1-[SiMe2(CH2CHdouble bond; length as m-dashCH2)]2C5H4 with NbCl5 gave the new allylsilyl-substituted monocyclopentadienyl niobium complex [Nb{η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}Cl4]. This compound was reacted with LiNHtBu or NH2tBu to give the imido derivative [Nb{η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}(NtBu)Cl2], which was further alkylated to the imido alkyl complexes [Nb{η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}(NtBu)R2] (R = Me, CH2Ph) and [Nb{η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}(NtBu)Cl (CH2Ph)]. Reaction of the imido complexes with the corresponding lithium cyclopentadienides gave the dicyclopentadienyl-imido complexes [M(η5-C5R5){η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}(NtBu)Cl] (M = Nb, Ta; R = H, Me). Metallocene dichlorides [M(η5-C5R5){η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}Cl2] (M = Nb, Ta; R = H, Me) were easily prepared by reduction with Na/Hg and simultaneous transmetallation of [Ta(η5-C5R5)Cl4] with Li[C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)] and of [Nb{η5-C5H4SiMe2(CH2CHdouble bond; length as m-dashCH2)}Cl4] with Li(C5R5). All of the new compounds have been characterized by elemental analysis, and IR and NMR spectroscopy.Financial support of our work by MCyT (Project MAT2001-1309) is gratefully acknowledged

    Monopentamethylcyclopentadienyl isocyanide, amine and imido tantalum(V) complexes. X-ray crystal structure of [TaCp*Cl4(CN-2,6-Me2C6H3)]

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    [TaCp★Cl4](Cp★ = η5-C5Me5) reacts with isocyanides and amines to give the pseudo-octahedral adducts [TaCp★Cl4L] (L = 2,6-Me2C6H3NC, 1; 2,4,6-Me3C6H2NC, 2; tBuNC, 3; or C6H5NH2, 4). Reduction of 1, or alternatively of [TaCp★Cl4] in the presence of stoichiometric amounts of isocyanide, with two equivalents of Na/Hg gives the diamagnetic pseudo-octahedral tantalum(III) complex, [TaCp★Cl2(CN-2,6-Me2C6H3)35. Reaction of 4 with two equivalents of LiNEt2 affords the pseudo-octahedral imido complex [TaCp★Cl2(NC6H5). 6. All the complexes were characterized by usual IR and NMR spectroscopic methods and the molecular structure of I was confirmed by X-ray diffraction methods

    Monopentamethylcyclopentadienyl isocyanide, amine and imido tantalum(V) complexes. X-ray crystal structure of [TaCp*Cl4(CN-2,6-Me2C6H3)]

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    [TaCp★Cl4](Cp★ = η5-C5Me5) reacts with isocyanides and amines to give the pseudo-octahedral adducts [TaCp★Cl4L] (L = 2,6-Me2C6H3NC, 1; 2,4,6-Me3C6H2NC, 2; tBuNC, 3; or C6H5NH2, 4). Reduction of 1, or alternatively of [TaCp★Cl4] in the presence of stoichiometric amounts of isocyanide, with two equivalents of Na/Hg gives the diamagnetic pseudo-octahedral tantalum(III) complex, [TaCp★Cl2(CN-2,6-Me2C6H3)35. Reaction of 4 with two equivalents of LiNEt2 affords the pseudo-octahedral imido complex [TaCp★Cl2(NC6H5). 6. All the complexes were characterized by usual IR and NMR spectroscopic methods and the molecular structure of I was confirmed by X-ray diffraction methods

    COVID-19 in hospitalized HIV-positive and HIV-negative patients : A matched study

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    CatedresObjectives: We compared the characteristics and clinical outcomes of hospitalized individuals with COVID-19 with [people with HIV (PWH)] and without (non-PWH) HIV co-infection in Spain during the first wave of the pandemic. Methods: This was a retrospective matched cohort study. People with HIV were identified by reviewing clinical records and laboratory registries of 10 922 patients in active-follow-up within the Spanish HIV Research Network (CoRIS) up to 30 June 2020. Each hospitalized PWH was matched with five non-PWH of the same age and sex randomly selected from COVID-19@Spain, a multicentre cohort of 4035 patients hospitalized with confirmed COVID-19. The main outcome was all-cause in-hospital mortality. Results: Forty-five PWH with PCR-confirmed COVID-19 were identified in CoRIS, 21 of whom were hospitalized. A total of 105 age/sex-matched controls were selected from the COVID-19@Spain cohort. The median age in both groups was 53 (Q1-Q3, 46-56) years, and 90.5% were men. In PWH, 19.1% were injecting drug users, 95.2% were on antiretroviral therapy, 94.4% had HIV-RNA < 50 copies/mL, and the median (Q1-Q3) CD4 count was 595 (349-798) cells/μL. No statistically significant differences were found between PWH and non-PWH in number of comorbidities, presenting signs and symptoms, laboratory parameters, radiology findings and severity scores on admission. Corticosteroids were administered to 33.3% and 27.4% of PWH and non-PWH, respectively (P = 0.580). Deaths during admission were documented in two (9.5%) PWH and 12 (11.4%) non-PWH (P = 0.800). Conclusions: Our findings suggest that well-controlled HIV infection does not modify the clinical presentation or worsen clinical outcomes of COVID-19 hospitalization

    How do women living with HIV experience menopause? Menopausal symptoms, anxiety and depression according to reproductive age in a multicenter cohort

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    CatedresBackground: To estimate the prevalence and severity of menopausal symptoms and anxiety/depression and to assess the differences according to menopausal status among women living with HIV aged 45-60 years from the cohort of Spanish HIV/AIDS Research Network (CoRIS). Methods: Women were interviewed by phone between September 2017 and December 2018 to determine whether they had experienced menopausal symptoms and anxiety/depression. The Menopause Rating Scale was used to evaluate the prevalence and severity of symptoms related to menopause in three subscales: somatic, psychologic and urogenital; and the 4-item Patient Health Questionnaire was used for anxiety/depression. Logistic regression models were used to estimate odds ratios (ORs) of association between menopausal status, and other potential risk factors, the presence and severity of somatic, psychological and urogenital symptoms and of anxiety/depression. Results: Of 251 women included, 137 (54.6%) were post-, 70 (27.9%) peri- and 44 (17.5%) pre-menopausal, respectively. Median age of onset menopause was 48 years (IQR 45-50). The proportions of pre-, peri- and post-menopausal women who had experienced any menopausal symptoms were 45.5%, 60.0% and 66.4%, respectively. Both peri- and post-menopause were associated with a higher likelihood of having somatic symptoms (aOR 3.01; 95% CI 1.38-6.55 and 2.63; 1.44-4.81, respectively), while post-menopause increased the likelihood of having psychological (2.16; 1.13-4.14) and urogenital symptoms (2.54; 1.42-4.85). By other hand, post-menopausal women had a statistically significant five-fold increase in the likelihood of presenting severe urogenital symptoms than pre-menopausal women (4.90; 1.74-13.84). No significant differences by menopausal status were found for anxiety/depression. Joint/muscle problems, exhaustion and sleeping disorders were the most commonly reported symptoms among all women. Differences in the prevalences of vaginal dryness (p = 0.002), joint/muscle complaints (p = 0.032), and sweating/flush (p = 0.032) were found among the three groups. Conclusions: Women living with HIV experienced a wide variety of menopausal symptoms, some of them initiated before women had any menstrual irregularity. We found a higher likelihood of somatic symptoms in peri- and post-menopausal women, while a higher likelihood of psychological and urogenital symptoms was found in post-menopausal women. Most somatic symptoms were of low or moderate severity, probably due to the good clinical and immunological situation of these women
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