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1.
Chempluschem ; : e202400123, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593349

RESUMO

The enantiomerically pure Schiff base ligands H2L-S and H2L-R yield chiral heterometallic dodecanuclear complexes of the form [Cu8Ln4(OH)8(OMe)4(O2CBut)8(L-S or L-R)4(H2O)4] where LnIII=Gd (1S), Tb (2S), Dy (3S, 3R), Ho (4S, 4R), Er (5S) or Y (6S, 6R) and H2L=(S or R)-2-{[(1-hydroxypropan-2-yl)imino]methyl}-6-methoxyphenol. The complexes are isomorphous and crystallize in the non-centrosymmetric polar space group C2 in enantiomeric conformation. The chirality of the Schiff base ligands originates from the respective S- or R- enantiomer of 2-aminopropan-1-ol, is imparted to the complexes and to the crystals that belong to non-centrosymmetric space group. The chirality and enantiomeric conformation of all complexes are retained in dmso solutions as confirmed by Circular Dichroism spectra which consist of mirror images, expected for enantiomeric pairs. All complexes consist of four distorted cubane-like subunits [Cu2Ln2(µ3-OH)2(µ3-OMe)(µ3-OR)], which share the LnIII ions and result in a cyclic distorted tetragonal arrangement; each edge of the {LnIII 4} quadrilateral is occupied by two µ-OH- ions that further bridge to a CuII ion. Magnetic susceptibility measurements revealed ferromagnetic interactions for 3S with LnIII=Dy and antiferromagnetic interactions for all other complexes. AC susceptibility data of 3S under 1 kOe external dc field indicate slow magnetic relaxation phenomena below 2 K.

2.
Dalton Trans ; 50(1): 240-251, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33295895

RESUMO

In addition to previously studied {CuGd6}, {CuGd4}, {CuLn7} and {CuLn8} coordination clusters (Ln = trivalent lanthanide) containing pdm2- or Hpdm- ligands (H2pdm = pyridine-2,6-dimethanol) and ancillary carboxylate groups (RCO2-), the present work reports the synthesis and study of three new members of a fifth family of such complexes. Compounds [Cu5Ln4O2(OMe)4(NO3)4(O2CCH2But)2(pdm)4(MeOH)2] (Ln = Dy, 1; Ln = Tb, 2; Ln = Ho, 3) were prepared from the reaction of Ln(NO3)3·xH2O (x = 5, 6), CuX2·yH2O (X = ClO4, Cl, NO3; y = 6, 2 and 3, respectively), H2pdm, ButCH2CO2H and Et3N (2 : 2.5 : 2 : 1 : 9) in MeCN/MeOH. Rather surprisingly, the copper(ii)/yttrium(iii) analogue has a slightly different composition, i.e. [Cu5Y4O2(OMe)4(NO3)2(O2CCH2But)4(pdm)4(MeOH)2] (4). The structures of 1·4MeCN·1.5MeOH and 4·2MeOH were solved by single-crystal X-ray crystallography. The five CuII and four DyIII centres in 1 are held together by two µ5-O2-, four µ-MeO-, two syn,synη1:η1:µ ButCH2CO2-, four η2:η1:η2:µ3 pdm2- (each of these groups chelates a CuII atom and simultaneously bridges two DyIII atoms through its two -CH2O- arms) and two µ-MeOH ligands. The four terminal nitrato groups each chelate (η1:η1) a DyIII centre. The five CuII atoms are co-planar (by symmetry) forming a bow-tie arrangement; the four outer CuII atoms form a rectangle with edges of 3.061(1) and 6.076(1) Å. The four DyIII centres also form a rectangle that lies above and below the plane of the CuII centres, with edges of 3.739(1) and 5.328(1) Å. The two strictly planar rectangles are almost perpendicular. Two trigonal bipyramidal µ5-O2- groups link the perpendicular Cu5 and Dy4 frameworks together. The molecule 4 has a very similar structure to that of 1, differences being the replacement of the two chelating nitrato groups of 1 by two chelating ButCH2CO2- ligands in 4 and the coordination polyhedra of the LnIII and YIII atoms (Snub diphenoids in 1 and biaugmented trigonal prisms in 4). Dc magnetic susceptibility data (χM) on analytically pure samples of 1-3, collected in the 300-2 K range, indicate that ferromagnetic exchange interactions dominate leading to large spin ground states. The χMT vs. T data for 4 suggest moderately strong antiferromagnetic CuIICuII exchange interactions. Studies of the dynamic magnetic properties of the {Cu5Ln4} clusters show that 1 behaves as a SMM at zero field and 2 is a very weak field-induced SMM, while 3 exhibits only weak tails in the χ''Mvs. T plots at various ac frequencies at zero dc field.

3.
Case Rep Anesthesiol ; 2017: 8641641, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28695018

RESUMO

We present the case of a patient who suffered from Takotsubo cardiomyopathy (TCM) immediately after the initiation of subarachnoid anesthesia for a minimally invasive urologic procedure (tension-free vaginal tape (TVT) surgery for stress urine incontinence). TCM mimics acute coronary syndrome and is caused by an exaggerated sympathetic reaction to significant emotional or physical stress. Our patient suffered from chest pain, palpitations, dyspnea, and hemodynamic instability immediately following subarachnoid anesthesia and later in the postanesthesia care unit. Blood troponin was elevated and new electrocardiographic changes appeared indicative of cardiac ischemia. Cardiac ultrasound indicated left ventricular apical akinesia and ballooning with severely affected contractility. The patient was admitted to coronary intensive care for the proper care and finally was discharged. TCM was attributed to high emotional preoperative stress for which no premedication had been administered to the patient. In conclusion, adequate premedication and anxiety management are not only a measure to alleviate psychological stress of surgical patients, but, more importantly, an imperative mean to suppress sympathetic nerve system response and its cardiovascular consequences.

4.
Inorg Chem ; 54(15): 7555-61, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26200217

RESUMO

The first use of tert-butylacetate as bridging ligand in 3d/4f-metal cluster chemistry, in conjunction with the versatile chelate ligand pyridine-2,6-dimethanol, has afforded a new family of [Cu4Ln8(OH)6(NO3)2(O2CCH2Bu(t))16(pdm)4] clusters with unprecedented structures and slow magnetization relaxation for the {Cu(II)4Dy(III)8} member. The molecular structure of representative complex 1 consists of a {Cu(II)4Gd(III)8} cage-like cluster built from two {CuGd3} cubanes which are linked to each other and to two {CuGd} subunits on opposite sides through two η(2):η(2):η(2):µ5 NO3(-) ions. The metal ions are additionally bridged by µ3-OH(-), µ3-OR(-), and µ-OR(-) groups to give an overall [Cu4Gd8(µ5-NO3)2(µ3-OH)6(µ3-OR)2(µ-OR)8](14+) core. Peripheral ligation about the core is provided by the N,O,O-chelating part of the pdm(2-) groups and, more impressively, by the oxygen atoms of 16 bridging Bu(t)CH2CO2(-) ligands; the latter are arranged into five classes, adopting a total of six different binding modes with the metal centers. The combined work demonstrates the ligating flexibility of tert-butylacetate ion and its usefulness in the synthesis of new 3d/4f-metal cluster compounds.

5.
Dalton Trans ; 43(39): 14520-4, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25140887

RESUMO

The initial 'accidental', metal ion-assisted hydrolysis of PF6(-) to PO3F(2-) has been evolved in a systematic investigation of the bridging affinity of the latter group in Ni(II)/oximate chemistry; mono-, di- and trinuclear complexes have been prepared and confirmed both the rich reactivity of PO3F(2-) and its potential for further use as bridging ligand in high-nuclearity 3d-metal cluster chemistry.


Assuntos
Complexos de Coordenação/química , Flúor/química , Níquel/química , Fósforo/química , Íons/química , Ligantes , Modelos Moleculares
6.
Eur J Clin Invest ; 43(12): 1299-306, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24147598

RESUMO

BACKGROUND: Growth factors mediate various cellular responses to environmental stimuli. Specifically, exposure of lung epithelium to oxidative stress induced by cigarette smoke stimulates aberrant epidermal growth factor receptor (ERBB) family activation. This study's objective was to evaluate the expression of ERBB1-4 receptors in the lung tissue of smokers with or without chronic obstructive pulmonary disease (COPD). MATERIALS AND METHODS: ERBBs expression was measured by microarray analysis in lung tissue samples from five patients with COPD and five non-COPD smokers, and by quantitative real-time PCR in additional 20 patients with COPD (GOLD stage II), 15 non-COPD smokers and 10 nonsmoker controls. RESULTS: Microarray data analysis revealed that ERBB receptors expression was elevated in patients with COPD compared to non-COPD smokers, ranging from 1·62- to 2·45-fold, (P < 0·01). Real-time qPCR verified that patients with COPD had higher ERBB1-3 expression levels compared with non-COPD smokers (PERBB1  < 0·001; PERBB2  = 0·003; PERBB3  = 0·003) and nonsmokers (PERBB1  = 0·019; PERBB2  = 0·005; PERBB3  = 0·011). On the other hand, ERBB4 mRNA levels gradually increased from nonsmokers (0·74 ± 0·19) to non-COPD smokers (1·11 ± 0·05) to patients with COPD (1·57 ± 0·28) and were correlated with the degree of airflow obstruction (PFEV1  < 0·001). DISCUSSION: These data suggest that ERBB1-3 overexpression is not related only to smoking exposure but probably to epithelial remodelling and mucociliary system distortion, characterizing COPD. Additionally, the inverse correlation of ERBB4 with FEV1 exhibits a possible link between ERBB4 and COPD severity.


Assuntos
Obstrução das Vias Respiratórias/metabolismo , Receptores ErbB/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , DNA Complementar/biossíntese , Volume Expiratório Forçado/fisiologia , Humanos , Pulmão/metabolismo , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fumar/metabolismo , Capacidade Vital/fisiologia
7.
Inorg Chem ; 52(18): 10235-7, 2013 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-24006940

RESUMO

The employment of pyridine-2,6-dimethanol in 3d/4f metal cluster chemistry has afforded a new {Cu(II)15Gd(III)7} cagelike molecule with a beautiful structure built by fused triangular subunits; the compound exhibits an overall ferrimagnetic behavior with an appreciable ground-state spin value and shows promise as a low-temperature magnetic refrigerant.

8.
Respiration ; 85(3): 228-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22869416

RESUMO

BACKGROUND: The mechanical stress that the human diaphragm is exposed to during mechanical ventilation affects a variety of processes, including signal transduction, gene expression, and angiogenesis. OBJECTIVES: The study aim was to assess the change in the production of major angiogenic regulators [vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF2), and transforming growth factor beta 1 (TGFB1)] on the human diaphragm before and after contraction/relaxation cycles during mechanical ventilation. METHODS: This observational study investigates the diaphragmatic mRNA expression of VEGF, FGF2, and TGFB1 in surgical patients receiving general anesthesia with controlled mechanical ventilation (CMV) with muscle relaxation (group A, n = 13), CMV without muscle relaxation (group B, n = 10), and pressure support of spontaneous breathing (group C, n = 9). Diaphragmatic samples were obtained from each patient at two time points: 30 min after the induction of anesthesia (t1) and 90 min after the first specimen collection (t2). RESULTS: No significant changes in the mRNA expression of VEGF, FGF2, and TGFB1 were documented in groups A and C between time points t1 and t2. In contrast, in group B, the mRNA levels of the above angiogenic factors were increased in time point t2 compared to t1, a finding which was statistically significant (pVEGF = 0.003, pFGF2 = 0.028, pTGFB1 = 0.001). CONCLUSIONS: These findings suggest that the molecular response of the human diaphragm before and after application of diverse modes of mechanical ventilation is different. Angiogenesis via the expression of VEGF, FGF2, and TGFB1 was only promoted in CMV without muscle relaxation, and this may have important clinical implications.


Assuntos
Diafragma/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Respiração Artificial , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Anestesia Geral , Feminino , Humanos , Pessoa de Meia-Idade , Relaxamento Muscular , Neovascularização Fisiológica
9.
Surg Oncol ; 19(1): 33-7, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19299121

RESUMO

OBJECTIVE: Recent studies reported that endometriosis could behave as a neoplasmatic process. The purpose of this study is to investigate the family risk of ovarian, colon and prostate cancer in women with endometriosis. STUDY DESIGN: A search of medical records at the Yale New Haven Hospital from 1996 to 2002 identified 348 women with endometriosis and 179 women without endometriosis. All the cases were diagnosed by laparoscopy. Demographic characteristics were evaluated in women with positive or negative family history of cancers in women with endometriosis. RESULTS: The overall risk of patients with endometriosis and positive family history of cancers was 7.7 (95% confidence interval 3.8-15.7) (chi(2)=39.8, P<0.001). Significant excess was observed for ovarian cancer in first- and second-degree relatives (OR=10.5, 95% CI (2.5-44.2), chi(2)=14.3, P<0.001), colon cancer (OR=7.5, 95% CI (2.7-21.1), chi(2)=18.2, P<0.001) and prostate cancer (OR=4.5, 95% CI (14-15.3), chi(2)=6.1, P<0.001). We found similar results in first- and second-degree relatives with ovarian and colon cancer. Moreover, we found similar results regarding the demographic characteristics in women with positive family history of cancers and in women with negative history. CONCLUSIONS: These data suggest a familial association of endometriosis with ovarian, colon and prostate cancers. This evidence could support the genetics and molecular similarities between endometriosis and cancer. Future studies will be important to determine a clear genetic link between endometriosis and cancer.


Assuntos
Neoplasias Colorretais/genética , Endometriose/genética , Neoplasias Ovarianas/genética , Neoplasias da Próstata/genética , Adulto , Estudos de Casos e Controles , Neoplasias Colorretais/epidemiologia , Intervalos de Confiança , Connecticut , Feminino , Humanos , Masculino , Anamnese , Razão de Chances , Neoplasias Ovarianas/epidemiologia , Neoplasias da Próstata/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
10.
Gynecol Endocrinol ; 24(4): 194-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18382905

RESUMO

BACKGROUND: There are conflicting data concerning endometriosis and spontaneous abortion (SAB). The aim of the present study was to evaluate if there was any association between endometriosis and SAB. Moreover, we investigated risk factors in women with endometriosis and SAB. METHODS: The medical files of 457 married women with endometriosis and 200 infertile women without endometriosis were studied retrospectively. All cases were diagnosed by laparoscopy. Data concerning demographic variables and menstrual characteristics were recorded from 226 women with endometriosis, which were divided into two groups. Group 1 included 126 cases with endometriosis and SAB, and Group 2 comprised 100 parous women with endometriosis and without SAB. Statistical comparisons between groups were made using the chi(2) test and odds ratios (OR) and 95% confidence intervals (CI). RESULTS: The proportion of SAB was significantly higher in women with endometriosis than in infertile women without endometriosis (126/457 (27.6%) vs. 36/200 (18.0% ); OR = 1.7, 95% CI 1.1 = 2.6; p = 0.01). The frequency of nulligravid women was significantly higher in women with endometriosis than in the control group (OR = 1.9, 95% CI 1.4 - 2.81; p = 0.001). Mean age, age at onset of endometriosis, race, height, weight, body mass index, medical history of allergies, and family histories of endometriosis and cancer were similar in women with endometriosis and SAB and in parous women with endometriosis but without SAB. Moreover, the two groups were similar in age at menarche, length of cycle, duration and amount of flow, and the severity of disease. The incidence of infertility was significantly higher in women with SAB (p < 0.001). CONCLUSION: These data suggest but do not prove that the risk of SAB is increased in women with endometriosis. The epidemiological risk factors of endometriosis are not associated with an increase in the abortion rate.


Assuntos
Aborto Espontâneo/etiologia , Endometriose/etiologia , Fertilização in vitro/efeitos adversos , Infertilidade Feminina/terapia , Aborto Espontâneo/epidemiologia , Adolescente , Adulto , Estudos de Casos e Controles , Endometriose/epidemiologia , Feminino , Fertilização in vitro/estatística & dados numéricos , Humanos , Infertilidade Feminina/complicações , Infertilidade Feminina/epidemiologia , Pessoa de Meia-Idade , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco
11.
Cardiovasc Drugs Ther ; 17(1): 31-9, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12843685

RESUMO

PURPOSE: To assess the effects of amiodarone and diltiazem on atrial fibrillation (AF) induced atrial electrical remodeling and their clinical implications. METHODS: Persistent AF patients were randomly assigned to three treatment groups over a period from 6 weeks before to 6 weeks after internal cardioversion: group A (35 patients, oral diltiazem), group B (34 patients, oral amiodarone) and group C (37 patients, no antiarrhythmic drugs). Several electrophysiological parameters were assessed 5 min and 24 h after cardioversion. RESULTS: Compared with controls, group B patients had significantly higher conversion rates (83% vs. 100%, p = 0.041) and a higher probability to maintain sinus rhythm (p = 0.037). Patients of group B had longer fibrillatory cycle length intervals than patients of group A and C (180 +/- 18 ms vs. 161 +/- 17 ms vs. 164 +/- 19 ms, p = 0.001) and longer atrial effective refractory periods (211 +/- 22 ms vs. 198 +/- 16 ms vs. 194 +/- 17 ms, p = 0.003) as assessed 5 min after conversion. Post-conversion density of supraventricular ectopics was significantly lower in group B compared to groups A and C (p = 0.001). CONCLUSIONS: Oral amiodarone increases conversion rates, prolongs fibrillatory cycle length and atrial effective refractory period and preserves sinus rhythm after cardioversion in persistent AF patients by suppressing the atrial ectopics that trigger AF.


Assuntos
Amiodarona/uso terapêutico , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/prevenção & controle , Fibrilação Atrial/terapia , Diltiazem/uso terapêutico , Cardioversão Elétrica , Idoso , Fibrilação Atrial/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Canais de Cálcio Tipo L/efeitos dos fármacos , Doença Crônica , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prevenção Secundária
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