Cloud point extraction for the determination of copper, nickel and cobalt ions in environmental samples by flame atomic absorption spectrometry

A cloud point extraction procedure was presented for the preconcentration of copper, nickel and cobalt ions in various samples. After complexation with methyl-2-pyridylketone oxime (MPKO) in basic medium, analyte ions are quantitatively extracted to the phase rich in Triton X-114 following centrifugation. 1.0 mol L(-1) HNO(3) nitric acid in methanol was added to the surfactant-rich phase prior to its analysis by flame atomic absorption spectrometry (FAAS). The adopted concentrations for MPKO, Triton X-114 and HNO(3), bath temperature, centrifuge rate and time were optimized. Detection limits (3 SDb/m) of 1.6, 2.1 and 1.9 ng mL(-1) for Cu(2+), Co(2+) and Ni(2+) along with preconcentration factors of 30 and for these ions and enrichment factor of 65, 58 and 67 for Cu(2+), Ni(2+) and Co(2+), respectively. The high efficiency of cloud point extraction to carry out the determination of analytes in complex matrices was demonstrated. The proposed procedure was applied to the analysis of biological, natural and wastewater, soil and blood samples.

Pre-transplant calcium-phosphate-parathormone homeostasis as a risk factor for early graft dysfunction

While good organ quality and ideal transplant conditions eliminate many of the know factors that compromise initial graft function (IGF), poor early graft function (EGF) still occurs after living donor kidney transplantation (LDKT). Uncontrolled pre-transplant hypercalcemia and hyperparathyroidism are associated with impaired allograft function. Between April 2004 and January 2006, data were collected on 354 LDKT recipients including 252 males and 102 females, to determine risk factors for poor EGF, defined as either delayed or slow graft function (DGF or SGF). Of the 354 recipients, 318 (89%) had IGF, 22 (6.2%) had SGF and 14 (4%) had DGF. Donor female gender (P = 0.04) and duration on dialysis (P = 0.02) were associated with poor EGF. Recipients with DGF had higher serum phosphate (P = 0.07) and calcium x phosphate product ( P = 0.01) than recipients with IGF and SGF. The serum parathormone (PTH) levels were higher in recipients with SGF and DGF although the difference was not statistically significant (P = 0.1). Serum calcium levels did not correlate with the occurrence of poor EGF (P = 0.9). Our study suggests that serum phosphate and calcium x phosphate product serve as risk factors for DGF while serum PTH level may play a role as a risk factor for SGF and DGF.

Inflammation and pruritus in hemodialysis patients

Pruritus is a common problem in dialysis patients. The aim of this study was to determine the cause(s) of pruritus and its relationship with inflammatory proteins. In a cross sectional study, all patients on hemodialysis at the Emam Khomaine and Sina Hospital, Tehran, Iran who did not have any pruritus-producing skin lesions were studied. They were questioned about the occurrence of pruritus during the preceding two weeks. Variables including inflammatory proteins (C-reactive protein, albumin, ferritin, transferrin, fibrinogen), hemoglobin, red blood cell indices, iron, iron binding capacity, transferring saturation, urea, creatinine, calcium, phosphorus, calcium x phosphorus product, alkaline phosphatase and parathormone were determined. Data were analyzed using Anova or Chi-square tests for evaluation of difference between variables. Of the 164 patients studied, 80 (49%) had pruritus. Of these, 45 subjects (23.8%) had severe and 35 (21.3%) mild to moderate pruritus. There were no significant differences between groups with or without pruritus for age, sex, duration on dialysis, dialysis adequacy, cause of renal failure and erythropoetin usage. Mean CRP was 16.6 mg/L; 58.5% of the patients had CRP > 10 mg/L. There was no significant correlation between CRP levels and presence or severity of pruritus. Also, none of the other inflammatory proteins revealed any significant differences. Among the other parameters, only the mean MCV levels were significantly different between the three groups (P < 0.05). Our study suggests that inflammatory proteins do not play any part in hemodialysis associated pruritus.

Infertility among female renal transplant recipients

We studied 122 women with renal allograft transplantation to evaluate their reproductive systems. The patients were recruited from the three main kidney transplant surgery centers in Tehran, from September to October 2005. Fifteen (12%) patients were either in the menopausal stage or had hysterectomies, and the other 33(27%) were unmarried. Of the 76(62%) married women at the reproductive age, 10 (13.1%) had infertility that was defined as the failure of a married woman to conceive after 12 months of frequent intercourse without contraception. Three patients had male factor infertility, three others had ovulatory problems, and four cases were undefined. Only six cases were actively treated by ovulation induction +/- an intrauterine inducer (IUI); two patients became pregnant, while the other four refused infertility treatment. The reasons of unwillingness for infertility treatment included old age (40 years) in one patient, positive HBsAg in one, renal retransplantation in one, and previous clomiphene therapy failure in another. We conclude that the prevalence of infertility among female renal transplant recipients is the same as the general population, and the causes are mostly treatable. However, many are less motivated to be treated for this problem.

Preconcentration and separation of nickel, copper and cobalt using solid phase extraction and their determination in some real samples

A solid phase extraction method has been developed to separate and concentrate trace amounts of nickel, cobalt and copper ions from aqueous samples for the measurement by flame atomic absorption spectrometry. By the passage of aqueous samples through activated carbon modified by dithioxamide (rubeanic acid) (DTO), Ni2+, Cu2+ and Co2+ ions adsorb quantitatively. The recoveries of analytes at pH 5.5 with 500 mg solid phase were greater than 95% without interference from alkaline, earth alkaline and some metal ions. The enrichment factor was 330. The detection limits by three sigma were 0.50 microg L(-1) for copper, 0.75 microg L(-1) for nickel and 0.80 microg L(-1) for cobalt. The loading capacity was 0.56 mg g(-1) for Ni2+, 0.50 mg g(-1) for Cu2+ and 0.47 mg g(-1) for Co2+. The presented procedure was applied to the determination of analytes in tap, river and sea waters, vegetable, soil and blood samples with successfully results (recoveries greater than 95%, R.S.D. lower than 2% for n=3).

DNA interaction with Al-N,N'-bis(salicylidene)2,2'-phenylendiamine complex

The Al(III) complex, [Al(salophen)2H2O]NO3, was synthesized and characterized by spectroscopic (NMR and FT-IR) techniques. Then the binding of Schiff base complex of [Al(salophen)]+ type, where salophen denotes N,N'-bis(salicylidene) 2,2-phenylendiamine to calf thymus DNA, has been investigated by spectrophotometric, circular dichroism, spectrofluorometric, melting temperature and viscosimetric techniques. This Al(III) complex showed absorption hyperchromism in the range of 310-390 nm, increase in melting temperature, some structural changes in specific viscosity, when bound to calf thymus DNA. The binding constant has been determined using absorption measurement and found to be 1.82 x 10(3)M(-1) and 1.31 x 10(3)M(-1) in HEPES and Tris-HCl buffers, respectively. Also the fluorescence spectral characteristics and interaction of Al-salophen complex with DNA have been studied. Al-salophen bound to DNA showed a marked increase in the fluorescence intensity along with a bathochromic shift (5 nm). The intersection point of the binding isotherm indicated a binding site size of 12 bp per bound complex molecule in both HEPES and Tris-HCl buffers. The experimental results showed that the Al-salophen complex bound to DNA by non-intercalative mode and major groove binding was the preferred mode of interaction.

The effect of anionic and cationic surfactants on indicators and measurement of dissociation constants with two different methods

The effects of cationic cetyltrimethylammonium bromide (CTAB), hexadecylpyridinum chloride (HDPC) and anionic sodium dodecylsulphate (SDS) surfactants on dissociation constants and transition intervals of methyl red, methyl orange and cresol red were studied spectrophotometrically. The results show that all studied indicators strongly interacted with cationic micelles (CTAB and HDPC). In the case of methyl red, relatively strong interaction with anionic surfactant (SDS) was obtained. However, no effect of SDS on dissociation constants of cresol red and methyl orange was observed. The dissociation constants of indicators were calculated with both the proposed and known chemometric (DATAN) method with a reasonable agreement on the data achieved.

Developing a culturally valid and reliable quality of life questionnaire for diabetes mellitus

The aim of this study was to design a culturally adapted questionnaire for studying quality of life (QOL) among type 1 and 2 adult diabetes patients in the Islamic Republic of Iran. The 41 items on the questionnaire were based on qualitative research and covered general and health-related QOL. In a descriptive survey, 104 patients completed the questionnaire; 68 (65.4%) were female. Mean age was 50.5 years (standard deviation 12.8). Most patients (86.5%) had type 2 diabetes. Cronbach's alpha coefficient for the questionnaire was 0.98. The questionnaire successfully distinguished the lower QOL of patients suffering from pain in the limbs, loss of appetite, fatigue, constipation and itching. The questionnaire could determine both general and health-related QOL.

Professional competence: factors described by nurses as influencing their development

AIM

To discuss the results of a study that explored factors that may influence competence development.

BACKGROUND

Competence, a controversial issue in health care settings, affects many aspects of the nursing profession, including education, practice and management. Although a number of research and discussion papers have explored the issue, in particular the meaning and assessment of nursing competence, to date little research has explored factors identified by nurses themselves as influencing their development of professional competence.

METHODS

A purposive sample of 27 registered nurses was recruited from two university-affiliated hospitals. Data collection was by tape-recorded semi-structured interviews. Interviews were transcribed verbatim and analysed according to the qualitative methodology of content analysis.

FINDINGS

Six descriptive categories were identified from the data: experience, opportunities, environment, personal characteristics, motivation and theoretical knowledge.

CONCLUSIONS

The findings suggest that the factors influencing the process of developing professional competence in nursing extend across personal and extra-personal domains. An understanding of these factors may enhance the ability of nursing managers and educators to enable student and qualified nurses to pursue effective competency development pathways to prepare them to provide a high standard of care. These findings, which may have important implications for nursing practice, management and education, are being further tested in a larger study.

Development and validation of a new HPLC method for determination of lamotrigine and related compounds in tablet formulations

A simple HPLC method was developed and validated for quantitation of lamotrigine and its related substances which may coexist in solid pharmaceutical dosage forms. The HPLC separation was achieved on a C18 mu-Bondapack column (250 mm x 4.6 mm) using a mobile phase of acetonitrile-monobasic potassium phosphate solution (35:65, v/v) containing orthophosphoric acid to adjust pH to 3.5 at a flow rate of 1.5 ml/min. The UV detector was operated at 210 nm, and column temperature was adjusted at 40 degrees C. The method was validated for specificity, linearity, precision, accuracy, robustness and limit of quantitation. The degree of linearity of the calibration curves, the percent recoveries of lamotrigine and related substances, the limit of detection and quantitation, for the HPLC method were determined. The method was found to be simple, specific, precise, accurate, and reproducible. The method was applied for the quality control of commercial lamotrigine tablets to quantify the drug and its related substances and to check the formulation content uniformity.

Determination of organophosphorus pesticides in water samples by single drop microextraction and gas chromatography-flame photometric detector

In this paper we have developed single drop microextraction (SDME) with modified 1.00 microl microsyringe, followed by gas chromatography with flame photometric detector (GC-FPD) for determination of 13 organophosphorus pesticides (OPPs) in water samples. By using a 1.00 microl microsyringe the repeatability of drop volume and injection were improved, because of using maximum volume of microsyringe and no dead volume. On the other hand, the modification of needle tip caused increasing cross section of needle tip and increasing adhesion force between needle tip and drop, thereby increasing drop stability and achieving a higher stirrer speed (up to 1700 rpm). The method used 0.9 microl of carbon tetrachloride as extractant solvent, 40 min extraction time, stirring at 1300 rpm and no salt addition. The enrichment factor of this method ranged from 540 to 830. The linear ranges were 0.01-100 microg/l (four orders of magnitude) and limits of detection were 0.001-0.005 microg/l for most of analyte. The relative standard deviation (RSD%) for 2 microg/l of OPPs in water by using internal standard was in the range 1.1-8.6% (n = 5). The recoveries of OPPs from farm water at spiking level of 1.0 microg/l were 91-104%.

Unwanted Pregnancy Among Kidney Transplant Recipients in Iran

To investigate the incidence of unwanted pregnancy among kidney transplant recipients, we studied 86 pregnancies in 64 women with a transplanted kidney. Twenty-five pregnancies were unwanted (29.1%). Pregnancy was terminated by induced abortion in seven patients, and four pregnancies were lost due to spontaneous abortion with one intrauterine fetal death. Only 13 (52%) pregnancies resulted in a live birth. Most of the unwanted pregnancies occurred in women using coitus interruptus (92%) as the only method of contraception. It is concluded that because fertility greatly improves after kidney transplantation, it is necessary to have a family planning counseling session before surgery. If a patient is not interested in future pregnancy, an effective method of contraception should be offered. A woman who has decided against childbearing in the future may decide to have a tubal ligation at the time of transplantation surgery.

Fertility and contraceptive issues after kidney transplantation in women

PURPOSE

Our purpose was to investigate reproductive performance among kidney transplant recipients.

MATERIALS AND METHODS

We studied 126 kidney transplanted women 15 to 68 years of age including 33 who were single and 93 who were married.

RESULTS

Infertility was seen in 10.4% of those who desired pregnancy, a rate similar to the general population. The most common method of contraception was coitus interruptus (56%), 22% of patients had tubal ligation, 6% had husbands who had vasectomies, 14% were using condoms, and only 2% used oral contraceptives. Among 33 pregnancies, 16 were unintended (48.5%). Most of the patients with unwanted pregnancy were using coitus interruptus (93.7%). In the group with unintended pregnancy, abortion was induced in three, spontaneous abortion or intrauterine fetal death occurred in six, and only seven pregnancies resulted in a live birth (43.7%).

CONCLUSION

Kidney transplantation greatly improves fertility, so those who do not desire pregnancy should be protected by an effective method of contraception.