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1.
Materials (Basel) ; 16(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37445180

RESUMO

A new Cu(II) paddle-wheel-like complex with 4-vinylbenzoate was synthesized using acetonitrile as the solvent. The complex was characterized by X-ray crystal diffraction, FT-IR, diffuse reflectance spectroscopy, thermogravimetric, differential scanning calorimetric, magnetic susceptibility, and electronic paramagnetic resonance analyses. The X-ray crystal diffraction analysis indicated that each copper ion was bound at an equatorial position to four oxygen atoms from the carboxylate groups of the 4-vinylbenzoate ligand in a square-based pyramidal geometry. The distance between the copper ions was 2.640(9) Å. The acetonitrile molecules were coordinated at the axial position to the copper ions. Exposure of the Cu(II) complex to humid air promoted the gradual replacement of the coordinated acetonitrile by water molecules, but the complex structure integrity remained. The EPR spectra exhibited signals attributed to the presence of a mixture of the monomeric (S = ½) and dimeric (S = 1) copper species in a possible 3:1 ratio. The magnetic studies revealed a peak at 50-100 K, which could be associated with the oxygen absorption capacity of the Cu(II)-vba complex.

2.
J Inorg Biochem ; 242: 112097, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36812707

RESUMO

We synthesize and characterize nine copper(II) compounds. Four with general formula [Cu(NNO)(NO3)] and five mixed chelates [Cu(NNO)(N-N)]+, where NNO corresponds to asymmetric salen ligands (E)-2-((2-(methylamino)ethylimino)methyl)phenolate (L1) and (E)-3-((2-(methylamino)ethylimino)methyl)naphthalenolate (LN1); and their hydrogenated derivatives 2-((2-(methylamino)ethylamino)methyl)phenolate (LH1) and 3-((2-(methylamino)ethylamino)methyl)naphthalenolate (LNH1); and N-N correspond to 4,4'-dimethyl-2,2'-bipiridyne(dmbpy) or 1,10-phenanthroline (phen). Using EPR, the geometries of the compounds in solution in DMSO were assigned, [Cu(LN1)(NO3)] and [Cu(LNH1)(NO3)] a square-planar, [Cu(L1)(NO3)], [Cu(LH1)(NO3)], [Cu(L1)(dmby)]+ and [Cu(LH1)(dmby)]+ a square-based pyramid; and [Cu(LN1)(dmby)]+, [Cu(LNH1)(dmby)]+ and [Cu(L1)(phen)]+ and elongated octahedral. By X-ray it was observed that [Cu(L1)(dmby)]+ and. [Cu(LN1)(dmby)]+ presented a square-based pyramidal, and [Cu(LN1)(NO3)]+ a square-planar geometry. The electrochemical study showed that copper reduction process is a quasi-reversible system, where the complexes with hydrogenated ligands were less oxidizing. The cytotoxicity of the complexes was tested by MTT assay, all the compounds showed biological activity in HeLa cell line, the mixed compounds were the more active ones. Naphthalene moiety, imine hydrogenation and aromatic diimine coordination, increased biological activity. A structure-activity relationships were found: Log(IC50) =  - 1.01(Epc) - 0.35(Conjugated Rings) + 0.87, for Schiff base complexes and Log(IC50) = 0.078(Epc) - 0.32(Conjugated Rings) + 1.94, for hydrogenated complexes; the less oxidizing species with a great number of conjugated rings presented the best biological activity. Complexes-DNA binding constants were obtained by uv-vis studies using CT-DNA, the results suggested that the complexes can interact through the grooves, except the phenanthroline mixed complex that intercalate with DNA. Gel electrophoresis study with pBR 322 showed that compounds can produce changes in the form of DNA and some complexes can cleave DNA in the presence of H2O2.


Assuntos
Complexos de Coordenação , Bases de Schiff , Humanos , Bases de Schiff/farmacologia , Bases de Schiff/química , Cobre/química , Células HeLa , Peróxido de Hidrogênio , DNA/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Ligantes , Cristalografia por Raios X
3.
J Wildl Dis ; 52(3): 568-75, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27195682

RESUMO

We identified and compared gross and microscopic lesions associated with the cestode, Parorchites zederi, in the digestive tracts of three species of penguins (Spheniscidae): the Chinstrap ( Pygoscelis antarctica ), Gentoo ( Pygoscelis papua ), and Adélie penguins ( Pygoscelis adeliae ). The gastrointestinal tracts of 79 recently dead individuals (71 chicks and eight adults) were collected in locations throughout the Antarctic Peninsula during summer field trips in 2006-09. Parorchites zederi was found in the small intestine of 37 animals (47%), and 23 (62%) of these had parasite-associated lesions. The cestodes were either free in the intestinal lumen, clustered within mucosal ulcers, or deeply embedded in the intestinal wall. Histopathologic changes were most severe in adult Gentoo Penguins and included transmural fibrogranulomatous enteritis, hemorrhage, and edema. This report of pathology associated with P. zederi in the digestive tracts of penguins can serve as reference to monitor health in Antarctic birds associated with environmental changes.


Assuntos
Cestoides/patogenicidade , Spheniscidae/parasitologia , Animais , Regiões Antárticas , Meio Ambiente , Trato Gastrointestinal
4.
Ticks Tick Borne Dis ; 7(3): 498-501, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26874670

RESUMO

This is the first reported case of Babesia sp. in Antarctic penguins, specifically a population of Chinstrap penguins (Pygoscelis antarctica) in the Vapour Col penguin rookery in Deception Island, South Shetlands, Antarctica. We collected peripheral blood from 50 adult and 30 chick Chinstrap penguins. Examination of the samples by microscopy showed intraerythrocytic forms morphologically similar to other avian Babesia species in 12 Chinstrap penguin adults and seven chicks. The estimated parasitaemias ranged from 0.25×10(-2)% to 0.75×10(-2)%. Despite the low number of parasites found in blood smears, semi-nested PCR assays yielded a 274 bp fragment in 12 of the 19 positive blood samples found by microscopy. Sequencing revealed that the fragment was 97% similar to Babesia sp. 18S rRNA from Australian Little Penguins (Eudyptula minor) confirming presence of the parasite. Parasite prevalence estimated by microscopy in adults and chicks was higher (24% vs. 23.3%, respectively) than found by semi-nested PCR (16% vs. 13.3% respectively). Although sampled penguins were apparently healthy, the effect of Babesia infection in these penguins is unknown. The identification of Babesia sp. in Antarctic penguins is an important finding. Ixodes uriae, as the only tick species present in the Antarctic Peninsula, is the key to understanding the natural history of this parasite. Future work should address the transmission dynamics and pathogenicity of Babesia sp. in Chinstrap penguin as well as in other penguin species, such as Gentoo penguin (Pygoscelis papua) and Adélie penguin (Pygoscelis adeliae), present within the tick distribution range in the Antarctic Peninsula.


Assuntos
Babesia/genética , Babesiose/epidemiologia , Doenças das Aves/epidemiologia , Filogenia , Spheniscidae/parasitologia , Animais , Regiões Antárticas/epidemiologia , Babesia/classificação , Babesia/isolamento & purificação , Babesiose/parasitologia , Doenças das Aves/parasitologia , Eritrócitos/parasitologia , Ilhas , Ixodes/parasitologia , Microscopia , Parasitemia , Reação em Cadeia da Polimerase , Prevalência , RNA Ribossômico 18S/genética
5.
Int J Womens Health ; 5: 449-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23935389

RESUMO

BACKGROUND: The purpose of this paper is to report the long-term results of surgery without bowel resection in patients suffering from deep infiltrating endometriosis with rectovaginal or colorectal involvement. METHODS: This retrospective observational study identified 42 patients suffering with deep infiltrating endometriosis who underwent surgery. Conservative surgery was performed in 23 women (only one of them with bowel resection), and 19 women underwent a hysterectomy and bilateral salpingo-oophorectomy (HBSO). In the conservative surgery group, a later HBSO was performed in eight patients as a second operation. Pregnancies, recurrences, reoperations, use of hormone replacement therapy, and outcomes during long-term follow-up were analyzed. RESULTS: The average follow-up duration was 7 ± 5.7 years in conservative surgery cases. Only one patient was treated with sigmoid bowel resection in 1997 and had complications. In this conservative surgery group, 13 patients (56%) received medical treatment after surgery, 10 patients wanted to get pregnant (of whom seven [70%] were successful), and eight patients underwent a subsequent HBSO because of recurrent symptoms and/or endometrioma. Therefore, HBSO was performed in 27 patients, of whom 14 (51.8%) used hormone replacement therapy for 5.6 ± 3.6 years. No recurrences or complications were observed in patients after HBSO with or without hormone replacement therapy. CONCLUSION: Good clinical results can be obtained by performing only conservative surgery and/or HBSO without bowel resection, an alternative that could reduce the number of colorectal resections that are performed very frequently nowadays. After HBSO, patients may use hormone replacement therapy for several years with total satisfaction and well-being.

6.
Parasitol Res ; 112(5): 1877-81, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435921

RESUMO

The aim of this work is to contribute to the knowledge of gastrointestinal parasites of the Gentoo penguin (Pygoscelis papua) from 25 de Mayo/King George Island (South Shetlands, Antarctica). Gastrointestinal tracts of 37 fresh dead individuals (21 chicks, 10 juveniles, and 6 adults) were collected from December 2006 to February 2012 and examined for macroparasites. Four adult parasite species were found: one Cestoda species (Parorchites zederi), two Nematoda species (Stegophorus macronectes and Tetrameres wetzeli), and one Acanthocephalan (Corynosoma shackletoni). Two species of immature acanthocephalans, Corynosoma hamanni and Corynosoma bullosum, were found in a single host. This is the first record of Tetrameres wetzeli in Gentoo penguins. The low parasite richness observed could be related to the stenophagic and pelagic diet of this host species which feeds almost exclusively on krill.


Assuntos
Doenças das Aves/parasitologia , Trato Gastrointestinal/parasitologia , Helmintíase Animal/parasitologia , Helmintos/isolamento & purificação , Interações Hospedeiro-Parasita , Spheniscidae/parasitologia , Acantocéfalos/classificação , Acantocéfalos/isolamento & purificação , Acantocéfalos/ultraestrutura , Animais , Animais Selvagens/parasitologia , Regiões Antárticas , Cestoides/classificação , Cestoides/isolamento & purificação , Cestoides/ultraestrutura , Helmintos/classificação , Helmintos/ultraestrutura , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/veterinária , Ilhas , Microscopia Eletrônica de Varredura , Nematoides/classificação , Nematoides/isolamento & purificação , Nematoides/ultraestrutura , Especificidade da Espécie
7.
Environ Sci Pollut Res Int ; 20(5): 3300-11, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23093414

RESUMO

The presence of metals in the Antarctic environment is principally a natural phenomenon caused by geochemical characteristics of the region, although some anthropogenic activities can increase these natural levels. Antarctic penguins present several of the characteristics of useful sentinels of pollution in Antarctica such as they are long-lived species situated at the top of food web. The concentrations of Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd, and Pb were determined by inductively coupled plasma-mass spectrometry in samples of liver, kidney, muscle, bone, feather, and stomach contents of gentoo, chinstrap, and Adélie penguin (12 adults, five juveniles) from carcasses of naturally dead individuals collected opportunistically in the Antarctic Peninsula area. The obtained results showed that accumulation and magnification of several elements can be occurring, so that Cd and Se reached levels potentially toxic in some specimens. The presence of human activities seems to be increasing the presence of toxic metals such as Mn, Cr, Ni, or Pb in penguins.


Assuntos
Exposição Ambiental , Poluentes Ambientais/toxicidade , Metais/toxicidade , Spheniscidae/metabolismo , Oligoelementos/toxicidade , Envelhecimento , Animais , Regiões Antárticas , Monitoramento Ambiental , Poluentes Ambientais/metabolismo , Espectrometria de Massas , Metais/metabolismo , Especificidade da Espécie , Distribuição Tecidual , Oligoelementos/metabolismo
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