Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Clín. investig. ginecol. obstet. (Ed. impr.) ; 50(1): 100812-100812, Ene-Mar. 2023. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-214992

RESUMO

Sexual dysfunction is one of the common findings among chronic kidney disease (CKD) patients and can lead to a decline in sexual desire, fertility/potency, successful pregnancy, along with menorrhagia and occasionally, amenorrhoea. Successful kidney transplantation is an effective method to preserve sexual desire in both the sexes and to achieve successful pregnancy where reasonable planning can give favorable outcomes for both mother and embryo. This review summarizes some common reproductive alterations in men and women undergoing renal transplant.(AU)


La disfunción sexual es uno de los hallazgos comunes entre los pacientes con enfermedad renal crónica y puede provocar una disminución del deseo sexual, de la fertilidad, de la potencia, de la posibilidad de embarazo, además de menorragia y, ocasionalmente, amenorrea. El trasplante de riñón exitoso es un método efectivo para preservar el deseo sexual en ambos sexos y recuperar la posibilidad de un embarazo, para el que una planificación razonable brindará resultados favorables tanto para la madre como para el embrión. Esta revisión ha resumido algunas alteraciones reproductivas comunes en hombres y mujeres tras un trasplante renal.(AU)


Assuntos
Humanos , Masculino , Feminino , Transplante de Rim , Nefropatias , Disfunções Sexuais Fisiológicas , Assexualidade , Hormônios Esteroides Gonadais , Insuficiência Renal Crônica , Complicações na Gravidez , Gravidez
2.
Neurochirurgie ; 68(4): 426-431, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34543614

RESUMO

Failed back surgery syndrome (FBSS) is associated with persistent lower back pain after and despite one or more surgical interventions. A number of factors underlie and maintain FBSS and successful management of pain chiefly depends on identifying them. Pharmacological, surgical, and non-surgical therapeutic measures are taken to treat the pain. Spinal cord stimulation and nerve stimulation have been widely practiced in this regard and enhanced pain reduction and patient satisfaction. In hernia and recurrent disc degeneration and sagittal imbalance, discectomy and/or fusion are indicated. The present review focuses on FBSS and its underlying components and on available treatment options.


Assuntos
Síndrome Pós-Laminectomia , Dor Lombar , Estimulação da Medula Espinal , Discotomia , Síndrome Pós-Laminectomia/etiologia , Síndrome Pós-Laminectomia/terapia , Humanos , Dor Lombar/etiologia , Dor Lombar/terapia , Satisfação do Paciente , Resultado do Tratamento
3.
J Laryngol Otol ; 135(5): 426-435, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33883051

RESUMO

OBJECTIVE: This study aimed to measure the duration and recovery rate of olfactory loss in patients complaining of recent smell loss as their prominent symptom during the coronavirus disease 2019 outbreak. METHOD: This was a prospective telephone follow-up observational study of 243 participants who completed an online survey that started on 12 March 2020. RESULTS: After a mean of 5.5 months from the loss of smell onset, 98.3 per cent of participants reported improvement with a 71.2 per cent complete recovery rate after a median of 21 days. The chance of complete recovery significantly decreased after 131 days from the onset of loss of smell (100 per cent sensitive and 97.7 per cent specific). Younger age and isolated smell loss were associated with a rapid recovery, whereas accompanying rhinological and gastrointestinal symptoms were associated with longer loss of smell duration. CONCLUSION: Smell loss, occurring as a prominent symptom during the coronavirus disease 2019 pandemic, showed a favourable outcome. However, after 5.5 months from the onset, around 10 per cent of participants still complained of moderate or severe hyposmia.


Assuntos
Anosmia/diagnóstico , COVID-19/complicações , Transtornos do Olfato/etiologia , Adulto , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/virologia , Feminino , Seguimentos , Humanos , Irã (Geográfico)/epidemiologia , Transtornos do Olfato/diagnóstico , Pandemias , Gravidez , Estudos Prospectivos , Recuperação de Função Fisiológica/fisiologia , SARS-CoV-2/isolamento & purificação , Inquéritos e Questionários
4.
Rhinology ; 58(5): 471-476, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333750

RESUMO

BACKGROUND: To extend the previous study by Schriever and colleagues from 2018 providing normative data and re-investigating the reliability for U-Sniff test in children in additional countries. METHODOLOGY: A total of 388 children (196 boys, 192 girls) from eight countries (China, Germany, Iran, Netherlands, Norway, Oman, Paraguay, and Russia) participated in this study. The children were recruited from public local schools in those particular countries. The odor identification ability was evaluated using the U-Sniff test, a 12-item odor identification test developed for children. In addition, reliability was examined using test-retest design in the children for each country. RESULTS: The mean U-Sniff test score across all children was 10.3 +- 1.7 points. Normative data were established. A high test-retest reliability of the U-Sniff test was demonstrated across the eight participating countries. CONCLUSIONS: The U-Sniff test for children exhibits a high test-retest reliability on a global scale.


Assuntos
Odorantes , Olfato , Criança , China , Feminino , Alemanha , Humanos , Irã (Geográfico) , Masculino , Países Baixos , Noruega , Reprodutibilidade dos Testes , Olfato/fisiologia
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 190: 298-311, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-28941414

RESUMO

Binuclear palladium(II) complexes with metal-metal (d8-d8) bonding interaction were synthesized by reactions of the 1-methyl-1H-1,2,3,4-tetrazole-5-thiol (Hmtzt) or a mixture of Hmtzt and 1,3-propanediamine (1,3-pda) ligands. Complex [Pd2(µ-mtzt)4]·2CH3CN (1) was synthesized by the reaction of Pd(OAc)2 with Hmtzt dissolved in acetonitrile and complex [Pd2(µ-mtzt)2(mtzt)2(1,3-pda)] (2) was synthesized by reaction of a mixture of Hmtzt and 1,3-propanediamine (dissolved in methanol) with PdCl2 (dissolved in acetonitrile) and were identified through elemental analysis, IR, UV-Vis, 1H NMR, luminescence spectroscopy as well as single-crystal X-ray diffraction method. A single-crystal of complex 1 shows that two Pd(II) centers are linked together by four bridging tetrazole ligands providing a paddle wheel-like arrangement. Also a crystal structure of complex 2 shows that this complex possesses a symmetric structure in which one Pd atom is tetra-coordinated by four sulfur atoms to forms PdS4 and other Pd atom is tetra-coordinated by four nitrogen to forms PdN4 coordination sphere. Density functional theory (DFT) was performed in this study for the Hmtzt ligand and binuclear palladium(II) complexes (1) and (2). The DFT calculation shows PdII-PdII bond lengths of 2.831 and 3.086Å in complex 1 and 2, respectively which are close to the observed bond lengths of 2.802(11) and 3.0911(17)Å from single-crystal X-ray structure. The optimized geometry of the complexes is shown good agreement by X-ray data. Structural properties and molecular descriptors including bond lengths, bond angles, chemical hardness, dipole moment, HOMO-LUMO energy levels, electron transfer were analyzed. The IR spectroscopy was performed using VEDA4 software and UV-Vis spectra were analyzed using time-dependent density functional theory (TD-DFT) method. The theoretical and experimental data were also compared with each other.

7.
Reprod Sci ; 18(6): 545-50, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21285452

RESUMO

BACKGROUND AND PURPOSE: The sperm of infertile men with varicocele exhibit markedly high DNA damage that appears to be related to high oxidative stress (OS). Aminoguanidine (AG) is a specific inhibitor of the nitric oxide synthase (NOS) isoforms iNOS and an antioxidant, the effects of which decrease NO and peroxynitrite production. The aim of this study was to determine the effects of AG on sperm chromatin in varicocelized rats. METHODS: Thirty male Wistar rats were divided into 5 groups: control, sham, varicocele, and AG and placebo-treated groups. At 10 weeks after varicocele induction, sperm chromatin was evaluated in all groups, except in the treated groups. The treated groups received intraperitoneal injections of 50 mg/kg AG or placebo daily for 10 weeks and then were killed for chromatin assessment. Sperm chromatin was evaluated by aniline blue, acridine orange, toluidine blue, and chromomycin A(3) staining. RESULTS: The results of the 4 above tests were significantly increased between varicocele and control (and sham) groups (P < .05). CONCLUSION: The findings of this study suggest that AG improves sperm DNA fragmentation that is associated with infertility in varicocelized rats, and treatment with AG can reduce the damage to sperm DNA.


Assuntos
Fragmentação do DNA/efeitos dos fármacos , Inibidores Enzimáticos/uso terapêutico , Guanidinas/uso terapêutico , Infertilidade Masculina/tratamento farmacológico , Óxido Nítrico/fisiologia , Espermatozoides/efeitos dos fármacos , Animais , Cromatina/efeitos dos fármacos , Infertilidade Masculina/etiologia , Masculino , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Ratos , Ratos Wistar , Varicocele/complicações
8.
Iran Red Crescent Med J ; 13(12): 863-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22737430

RESUMO

BACKGROUND: Cutaneous leishmaniasis is still a health problem in many rural and urban regions of Iran and drug resistance has emerged as a major impediment in the treatment of leishmaniasis. This study aims to determine the drug resistance gene in cutaneous leishmaniasis by PCR in some endemic areas of Iran. METHODS: Ninety seven samples were collected from ulcers of leishmaniasis patients from some endemic areas of Iran. The Giemsa stained samples were examined microscopically and cultured in NNN and RPMI 1640 mediums for parasite detection. After DNA extraction, PCR was done by a pair of specific primers. For detection of mutation in DNA, first PCR products were electrophoresed on CSGE gel. The suspected samples were compared by sequencing and RFLP results were demonstrated. Comparison of DNA derived from a wild type cell and mutant cell was undertaken by CSGE and sequencing methods. RESULTS: Among 90 isolates (92.8%) examined for detection of mutation in gene with CSGE and RFLP, 10 (11.1%) revealed a disorder in sequencing selection for unresponsive to drug. CONCLUSION: Drug resistance in cutaneous leishmaniasis to sodium stiboglocanat is probably due to a mutation in a genome. A field study is needed to determine the distribution of drug resistance and other gene mutations involved in unresponsiveness to drugs in leishmaniasis endemic areas of Iran.

9.
Urol Int ; 86(3): 302-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21088382

RESUMO

INTRODUCTION: Increased levels of nitric oxide (NO) in the spermatic veins of men affected by varicocele have already been reported. But there is no study to discriminate the subtype of catalytic enzyme for synthesis of NO. In this study, aminoguanidine (AG), an inducible NO synthase inhibitor, has been used to investigate its effect on sperm parameters. METHODS: Twenty-four male Wistar rats were divided into four groups. In groups A and B, left experimental varicocele was induced by a 20-gauge needle. Group C (sham) underwent a similar procedure to groups A and B, but the spermatic vein was left intact, and group D served as control group. The animals in group A were killed 10 weeks later and their sperm count, motility, morphology and vitality were evaluated. Group B received 50 mg/kg AG with i.p. injection daily for 10 weeks. RESULTS: Sperm count, motility, morphology and vitality were significantly decreased in group A in comparison to control group (p ≤ 0.05). In group B, sperm parameters improved in comparison to group A (p ≤ 0.01). Group C did not show any significant alterations in sperm parameters compared with control group. CONCLUSION: These findings may support the concept that AG can improve the sperm count, motility, morphology and vitality in infertile rats with varicocele.


Assuntos
Epididimo/efeitos dos fármacos , Guanidinas/farmacologia , Varicocele/tratamento farmacológico , Animais , Inibidores Enzimáticos/farmacologia , Feminino , Infertilidade Masculina/patologia , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio , Motilidade dos Espermatozoides , Espermatozoides/patologia , Testículo/irrigação sanguínea
10.
Scand J Rheumatol ; 39(6): 447-53, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20604674

RESUMO

OBJECTIVE: To determine whether emerging cardiovascular risk factors such as anti-apolipoprotein A-1 (anti-apoA-1) immunoglobulin (Ig)G and oxidized low density lipoprotein (oxLDL) are associated with cardiovascular disease (CVD), carotid intima-media thickness (IMT), and disease activity in rheumatoid arthritis (RA). METHOD: We determined the aforementioned associations in 69 RA patients with disease duration of 5 years and 46 controls matched by age, sex, and smoking status. Anti-apoA-1 IgG and oxLDL were measured by enzyme-linked immunosorbent assay (ELISA). Carotid arteries were examined by ultrasound. Disease Activity Score calculated on 28 joints (DAS28) was used to assess disease activity. RESULTS: CVD prevalence was higher among RA patients than controls (17% vs. 2%, p = 0.01) but there was no difference in IMT (median: 0.67 vs. 0.66, p = 0.33). RA patients had a higher anti-apoA-1 IgG prevalence than controls (20% vs. 0%, p = 0.001). Anti-apoA-1 IgG and oxLDL levels were higher in cases than controls [median: 0.33 vs. 0.175 optical density (OD), p = 0.03; and 121 vs. 37.2 U/L, p = 0.0001, respectively]. Anti-apoA-1 IgG-positive patients had higher levels of oxLDL (median: 140.5 vs. 112 U/L, p = 0.01) than those tested negative. Receiver operating characteristic (ROC) curve analysis showed that only anti-apoA-1 IgG was a modest but significant predictor of CVD [area under the curve (AUC) = 0.65, p = 0.03] in RA patients. oxLDL was significantly associated with RA disease activity, whereas anti-apoA-1 IgG was not. CONCLUSIONS: Anti-apoA-1 IgG could be a marker of CVD in RA, whereas oxLDL levels seem to reflect RA disease activity. Other causes of CVD than a general increase in atherosclerosis (as determined by IMT measurements) including plaque stability may therefore be of importance to explain the increased incidence of CVD in RA.


Assuntos
Apolipoproteína A-I/imunologia , Artrite Reumatoide/sangue , Autoanticorpos/sangue , Doenças Cardiovasculares/epidemiologia , Imunoglobulina G/sangue , Lipoproteínas LDL/sangue , Artrite Reumatoide/imunologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico por imagem , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/epidemiologia , Estudos Transversais , Feminino , Humanos , Mediadores da Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Fumar , Túnica Íntima/diagnóstico por imagem , Ultrassonografia
11.
Iran J Parasitol ; 5(4): 9-14, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22347260

RESUMO

BACKGROUND: Trichomoniasis is a worldwide protozoan parasitic disease and metronidazole is a choice drug for its treatment. Because of disease importance in public health and its controversial ideas about the prevalence of drug resistance, this study was carried out. METHODS: Fifty-two suspected vaginal samples were collected from 2006 to 2007 in Gynecology Maryam Hospital, Tehran, Iran. All isolates were examined by microscopic, culture and PCR techniques. The PCR products were analyzed by RFLP and CSGE methods and two suspected samples were sequenced. RESULTS: Trichomonas vaginalis was identified from all 52 samples. Of 52 isolates, 45 samples were successfully cultured and amplified by PCR except one. Seven were positive only by PCR. Finally, ITS1 fragment was successfully amplified in 51 of 52. CSGE analysis and PCR products digestion by MspI followed by sequencing showed nucleotide mutation at position 209 (C209T) of the ITS1 fragment in two (3.9%) of them. CONCLUSION: The results showed mutation in ITS1 fragment of T. vaginalis in two (3.9%) of Iranian isolates which may be related to metronidazole resistance.

12.
Environ Monit Assess ; 165(1-4): 275-81, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19424817

RESUMO

In this study, variations of ambient ozone level are thoroughly analysed according to the monitored data in a mixed residential, commercial and industrial city, Tehran, based on considering the meteorological factors. Ozone as a pollutant shows typical annual, weekly and diurnal cycles. This analysis has shown that the ozone level concentrations were below the WHO guidelines in Tehran during 2000-2003. The relation between ozone level at two different stations (Aghdasieh and Fatemi) is found (r = 0.51). The ozone level response to meteorological parameters is investigated. The results suggest that the ozone level is affected (positively or negatively) by meteorological conditions, e.g. relative humidity, solar radiation, air temperature, wind speed and wind direction.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Ozônio/análise , Nível de Saúde , Irã (Geográfico) , Conceitos Meteorológicos
13.
Environ Monit Assess ; 155(1-4): 149-55, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18612833

RESUMO

This study performed a time-series analysis, frequency distribution and prediction of SO(2) levels for five stations (Pardisan, Vila, Azadi, Gholhak and Bahman) in Tehran for the period of 2000-2005. Most sites show a quite similar characteristic with highest pollution in autumn-winter time and least pollution in spring-summer. The frequency distributions show higher peaks at two residential sites. The potential for SO(2) problems is high because of high emissions and the close geographical proximity of the major industrial and urban centers. The ACF and PACF are nonzero for several lags, indicating a mixed (ARMA) model, then at Bahman station an ARMA model was used for forecasting SO(2). The partial autocorrelations become close to 0 after about 5 lags while the autocorrelations remain strong through all the lags shown. The results proved that ARMA (2,2) model can provides reliable, satisfactory predictions for time series.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Previsões/métodos , Modelos Estatísticos , Dióxido de Enxofre/análise , Irã (Geográfico)
14.
East Mediterr Health J ; 15(6): 1489-95, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20218142

RESUMO

A study in Babol, Islamic Republic of Iran, used a questionnaire to gather information on knowledge about oral cancer and its risk factors and to evaluate the efficacy of an educational brochure. From a community sample of 400 people, 76.0% had no knowledge of oral cancer. Mean knowledge score before the education intervention was 1.47 (standard deviation 3.40) out of 10. Knowledge about oral cancer was not associated with age, sex or education level but urban residents had better knowledge than rural residents. Mean knowledge score improved significantly by 5.92 (SD 3.30) at 1 month after the intervention among the 226 respondents who had read the brochure.


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias Bucais , Folhetos , Materiais de Ensino , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Estudos Transversais , Avaliação Educacional , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/etiologia , Características de Residência , Fatores de Risco , Estatísticas não Paramétricas , Inquéritos e Questionários , Materiais de Ensino/normas
15.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117789

RESUMO

A study in Babol, Islamic Republic of Iran, used a questionnaire to gather information on knowledge about oral cancer and its risk factors and to evaluate the efficacy of an educational brochure. From a community sample of 400 people, 76.0% had no knowledge of oral cancer. Mean knowledge score before the education intervention was 1.47 [standard deviation 3.40] out of 10. Knowledge about oral cancer was not associated with age, sex or education level but urban residents had better knowledge than rural residents. Mean knowledge score improved significantly by 5.92 [SD 3.30] at 1 month after the intervention among the 226 respondents who had read the brochure


Assuntos
Conhecimento , Educação em Saúde , Inquéritos Epidemiológicos , Inquéritos e Questionários , Fatores de Risco , Estudos Transversais , População Urbana , População Rural , Neoplasias Bucais
16.
Pak J Biol Sci ; 10(11): 1910-3, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19086559

RESUMO

In this research, the effect of 2, 6-diaminopyridinum as a new phenanthroline derivative was studied on the hypophysis-gonad axis, testicular tissue and sperm production in male Balb/C mice. Fifty adult male Balb/C mice were divided in five groups. First group was considered as untreated control. Saline was injected to second group and the remaining three groups received intraperitoneal injection of 15, 20 and 25 mg kg(-1) of 2, 6-diaminopyridinum every other day for 20 days. The LD50 was determined to be 35 mg kg(-1) body weight. The testicular tissues were studied morphologically and the serum concentration of FSH, LH and testosterone were measured. The results showed that 25 mg kg(-1) diaminopyridinum decreased the number of germ cells significantly and serum testosterone level with no change on FSH and LH levels. This study indicates that 25 mg kg(-1) of phenanthroline may directly affect testicular tissue causing a lower testosterone level and spermatogenesis in mice.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Fenantrolinas/farmacologia , Testículo/efeitos dos fármacos , Testosterona/sangue , Animais , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho do Órgão/efeitos dos fármacos
17.
Biomed Sci Instrum ; 40: 290-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15133973

RESUMO

The axial and rotational alignments of the lower extremity are commonly referenced independently, with minimal research on whether coexistent axial and rotational malalignment cause pathologies. The present study analyzed whether a correlation exists between the axial and rotational alignments of the leg. The methodology to measure both alignments was adapted for computer tomography. Fifty patients were analyzed at five reference images to determine axial and rotational alignment. The reference images included the femoral head, the femoral shaft (at the level of the lesser trochanter), the distal femur, the proximal tibia, and the ankle joint. Axial alignment was calculated by using horizontal and vertical measurements of the location of the femoral head, the distal femur, and the ankle joint. Rotational alignments of femur, knee, and tibia were calculated using four angles: proximal femoral, distal femoral, proximal tibial, and ankle joint angles defined relative to a fixed reference. Pearson correlation analysis between axial alignment and the three mentioned rotational alignments were calculated. The correlation coefficient values ranged between -0.15-0.07 when comparing axial to rotational alignment, indicating that a week correlation exists between the two alignments. Though these results were derived using highly reproducible methods, the hypothesis of an existing correlation between the axial and rotational alignments of the leg was rejected. These findings allow for an improved understanding of lower extremity mechanics, which merit importance when considering pathologies of the leg and the surgical techniques that could ultimately benefit patients suffering from these pathologies.


Assuntos
Articulação do Tornozelo/diagnóstico por imagem , Antropometria/métodos , Fêmur/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Perna (Membro)/diagnóstico por imagem , Rotação , Tíbia/efeitos da radiação , Adulto , Idoso , Articulação do Tornozelo/fisiopatologia , Feminino , Fêmur/fisiopatologia , Humanos , Articulação do Joelho/fisiopatologia , Perna (Membro)/fisiopatologia , Masculino , Pessoa de Meia-Idade , Radiografia , Amplitude de Movimento Articular , Estatística como Assunto , Tíbia/fisiopatologia
18.
Inorg Chem ; 42(5): 1616-24, 2003 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-12611530

RESUMO

The new 1,10-phenanthroline containing 1:1 proton-transfer compound LH(2), [pyda.H(2)](2+)[phendc](2-), was synthesized from the reaction of 2,6-pyridinediamine, pyda, and 1,10-phenanthroline-2,9-dicarboxylic acid, phendc.H(2), and characterized by elemental analysis, ES-Ms, IR, (1)H, (13)C NMR, and UV/vis spectroscopies. Subsequently, the first example of [phendc](2)(-) containing anionic complex [pyda.H](2)[Co(phendc)(2)].10H(2)O, was prepared, using the above novel proton-transfer compound, and structurally characterized by single-crystal X-ray diffraction. The complex crystallizes in the space group P2(1)/n of the monoclinic system with four molecules in a unit cell of dimensions a = 11.877(3) A, b = 31.473(9) A, c = 12.915(4) A, and beta = 116.223(5) degrees. The structure has been refined to a final value for the crystallographic R factor of 0.0524 based on 9021 observed independent reflections. The complexation reactions of pyda, phendc.H(2), and LH(2) with H(+) as well as LH(2) with Co(II) in aqueous solution were investigated by potentiometric pH titrations, and the equilibrium constants for all major complexes formed are described. The results are presented in the form of distribution diagrams revealing the concentrations of individual complex species as a function of pH. The results revealed that, at a pH range of 5.2-6.2, the major complex species is [(pyda.H)](2)[Co(phendc)(2)], similar to the isolated crystalline complex.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...