A web-based application for initial screening of living kidney donors: development, implementation and evaluation.

Most centers utilize phone or written surveys to screen candidates who self-refer to be living kidney donors. To increase efficiency and reduce resource utilization, we developed a web-based application to screen kidney donor candidates. The aim of this study was to evaluate the use of this web-based application. Method and time of referral were tabulated and descriptive statistics summarized demographic characteristics. Time series analyses evaluated use over time. Between January 1, 2011 and March 31, 2012, 1200 candidates self-referred to be living kidney donors at our center. Eight hundred one candidates (67%) completed the web-based survey and 399 (33%) completed a phone survey. Thirty-nine percent of donors accessed the application on nights and weekends. Postimplementation of the web-based application, there was a statistically significant increase (p < 0.001) in the number of self-referrals via the web-based application as opposed to telephone contact. Also, there was a significant increase (p = 0.025) in the total number of self-referrals post-implementation from 61 to 116 per month. An interactive web-based application is an effective strategy for the initial screening of donor candidates. The web-based application increased the ability to interface with donors, process them efficiently and ultimately increased donor self-referral at our center.

Photochemical reactions involved in the phototoxicity of the anticonvulsant and antidepressant drug lamotrigine (Lamictal).

Lamotrigine (LTG) [3,5-diamino-6-(2,3-dichlorophenyl)-1,2,4-triazine], an anticonvulsant and antidepressant drug Lamictal, produces a (photo)toxic response in some patients. LTG absorbs UV light, generating singlet oxygen (1O2) with a quantum yield of 0.22 in CH2Cl2, 0.11 in MeCN and 0.01 in D2O. A small production of superoxide radical anion was also detected in acetonitrile. Thus, LTG is a moderate photosensitizer producing phototoxicity and oxidizing linoleic acid. LTG is a weak 1O2 quencher (k(q) = 3.2 x 10(5) M(-1) s(-1) in MeCN), but its photodecomposition products in dimethyl sulfoxide (DMSO) quenched 1O2 very efficiently. Upon intense UV irradiation from a xenon lamp, LTG was photobleached rapidly in DMSO and slowly in acetonitrile, alcohol and water. The rate increased significantly when laser pulses at 266 nm were employed. The photobleaching products generated 1O2 twice as strongly as LTG. Photobleaching was usually accompanied by the release of chloride anions, which increased in the presence of ascorbic acid. This suggests the formation of aryl radicals via dechlorination, a process which may be responsible for the photoallergic response observed in some patients. Our results demonstrate that LTG is a moderate generator of 1O2 prone to photodechlorination, especially in a reducing environment, which can contribute to the reported phototoxicity of LTG.

Cost perspectives of laparoscopic and open appendectomy.

BACKGROUND: Despite multiple studies comparing laparoscopic and open appendectomies, the clinically and economically superior procedure still is in question. A cost analysis was performed using both institutional and societal perspectives. METHODS: A decision analytic model was developed to evaluate laparoscopic and open appendectomies. The institutional perspective addressed direct health care costs, whereas the societal perspective addressed direct and indirect health care costs. Baseline values and ranges were taken from randomized controlled trials, meta-analyses, and Medicare databases. RESULTS: From the institutional perspective, open appendectomy is the least expensive strategy, with an expected cost of $5,171, as compared with $6,118 for laparoscopic appendectomy. The laparoscopic approach is less expensive if open appendectomy wound infection rates exceed 23%. From the societal perspective, laparoscopic appendectomy is the least expensive strategy, with an expected cost of $10,400, as compared with $12,055 for open appendectomy. CONCLUSIONS: The decision analysis demonstrated an economic advantage to the hospital of open appendectomy. In contrast, laparoscopic appendectomy represents a better economic choice for the patient.

Identification and quantitation of sodium-thyroxine and its degradation products by LC using electrochemical and MS detection.

High performance liquid chromatography (HPLC) was used in combination with an amperometric and mass spectrometric detection to elucidate and quantitate the degradation products and contaminants of the photo-sensitive Na-thyroxine. Using HPLC with amperometric detection, seven decomposition compounds were separated. These products, which occur mostly as contaminants, were then identified by a developed liquid chromatography-mass spectrometry technique. The same HPLC method was also employed to analyze Na-thyroxine and its degradation products in three commercially available brands of Na-thyroxine tablets.

Bacteria in the transfer catheter tip influence the live-birth rate after in vitro fertilization.

OBJECTIVE: To assess the impact of individual bacteria isolated from the vagina and tip of the embryo transfer catheter on live-birth rates. DESIGN: Prospective clinical study. SETTING: Infertility outpatient clinic of a university hospital. PATIENT(S): Ninety-one women undergoing IVF-ET. INTERVENTION(S): Cultures were obtained from the vagina for aerobic and anaerobic bacteria at the time of both sonographic egg retrieval and embryo transfer and from the tip of the embryo transfer catheter. Doxycycline treatment was started after egg retrieval. MAIN OUTCOME MEASURE(S): The live birth of one or more neonates. RESULT(S): Doxycycline had no substantial impact on the recovery of individual vaginal bacteria or on bacterial vaginosis. An increase in live-birth rate was associated with the recovery of hydrogen peroxide-producing Lactobacillus from the vagina (P=0.01) and from the embryo transfer catheter (P=0.01). In contrast, a reduction in live-birth rate was associated with recovery of Streptococcus viridans (S. viridans) from the embryo transfer catheter tip (P=0.04). CONCLUSION(S): In the setting of IVF-ET, prophylactic doxycycline had little effect on vaginal bacteria. Specific bacteria recovered from the embryo transfer catheter appear associated with a detrimental or beneficial effect or with no effect on live-birth rates.

Photodegradation of amiloride in aqueous solution.

The photodegradation of amiloride hydrochloride in deaerated aqueous solution at 30 degrees C in the pH range 4.5-11.0 was studied by spectrophotometry and reversed-phase HPLC. The neutral form of the drug present in alkaline solution degraded approximately 3-fold faster than the cationic form. The quantum yields for photodegradation of neutral amiloride and its conjugate acid were determined using ferrioxalate actinometry to be 0.023+/-0.002 and 0. 009+/-0.001, respectively. The initial photoreaction involves dechlorination of amiloride and the major product is N-amidino-3, 5-diamino-6-hydroxylpyrazine-carboxamide, established by UV, 1H and 13C NMR, and chemical ionization-mass spectrometry. The mechanism of photolysis is postulated to involve cation radical formation that facilitates the dechlorination step. The photosensitizing activity of amiloride hydrochloride was tested by measuring (a) the rate of oxygen uptake in the presence of singlet oxygen substrates, 2, 5-dimethylfuran or l-histidine, and (b) the rate of free radical polymerization of acrylamide, at 30 degrees C in aqueous solution. Photosensitization by amiloride was concluded to occur predominantly via singlet oxygen rather than a free radical mechanism. However, amiloride is a much weaker photosensitizer than other diuretics such as frusemide and hydrochlorothiazide, tested under the same experimental conditions.

Characterization of ciliary activity in distal Fallopian tube biopsies of women with obstructive tubal infertility.

Biopsy specimens were obtained from the distal end of the Fallopian tubes of 62 women with tubal infertility and examined by light and electron microscopy. Ciliary beat frequency (CBF) measurements were obtained using laser light spectroscopy. Neither demographic nor behavioural characteristics nor serological evidence of past chlamydial infection were associated with CBF measurements. In contrast, CBF were significantly lower (P < 0.05) in tissues with oedema compared to tissues without oedema (6.7 versus 12.9) and in tissues with erythema compared to tissues without erythema (9.2 versus 13.7). Furthermore, CBF measurements did vary by chlamydial serotype pattern, with lower values observed among the tissues of women with antibodies to serotype C or E (without D) as compared to the tissues of women with other serotypes (P < 0.04). However, these data must be interpreted with caution as the numbers of subjects with chlamydial antibodies to serotype C (n = 3) or E without D (n = 5) were few in number and serotyping of IgG antibodies in blood is not as accurate as it is in bacterial isolates. Confirmation of the suggested association between chlamydial serotype and risk of adverse sequelae could indicate potential new avenues for vaccine research.

Electron transfer processes in the reactivity of nonsteroidal anti-inflammatory drugs in the ground and excited states.

The nonsteroidal anti-inflammatory drugs (NSAID), naproxen, sulindac and indomethacin, were shown to donate electrons to nitro blue tetrazolium (NBT) when irradiated with UV light in deoxygenated aqueous buffer solution (pH 7.4, 30 degrees C). The reaction was monitored spectrophotometrically by the appearance of the diformazan reduction product from NBT. The electron transfer process facilitates the decomposition of the drugs. Naproxen in the presence of NBT is photodegraded principally to the alcohol (2-[1-hydroxyethyl]-6-methoxynaphthalene) at a rate approximately 20-fold faster than when irradiated alone in deoxygenated conditions. The photoproduct from naproxen also participates in the electron transfer to NBT but at a much slower rate than naproxen. Irradiation of sulindac or indomethacin in the presence of NBT caused the slow photoreduction of NBT to diformazan. In the absence of NBT, indomethacin and sulindac are essentially unreactive when irradiated in aqueous solution. The ability of a number of NSAID to act as electron donors in their ground state was studied by observing their oxidation by potassium peroxodisulfate in pH 7.0 phosphate buffer at 50 degrees C. The HPLC analysis of the drug remaining showed that the 2-arylpropionic acid NSAID (naproxen, ibuprofen, ketoprofen and suprofen) reacted at a rate equivalent to the thermal decomposition of peroxodisulfate. The major products were the same as detected in the photooxidation of these drugs, resulting from decarboxylation and oxygen addition but also included a dimeric compound. On the other hand, the NSAID that do not contain the propionic acid substituent all reacted more slowly with peroxodisulfate, enabling specific reaction rate constants to be evaluated.

Maternal factors and breast cancer risk among young women.

The results from previous studies have provided evidence to support the hypothesised association between intrauterine oestrogen exposure and subsequent risk of breast cancer. Information has not been available to study this relationship for several perinatal factors thought to be related to pregnancy oestrogen levels. Data collected from the mothers of women in two population-based case-control studies of breast cancer in women under the age of 45 years (510 case mothers, 436 control mothers) who were diagnosed between 1983 and 1992 in three western Washington counties were used to investigate further the relationship between intrauterine oestrogen exposure and risk of breast cancer. A pregnancy weight gain of 25-34 pounds was associated with breast cancer risk (odds ratio [OR] = 1.5; 95% confidence interval [CI] 1.1, 2.0); however, women whose mothers gained 35 pounds or more were not at increased risk. Use of antiemetic medication in women with any nausea and vomiting (OR = 2.9; 95% CI 1.1, 8.1) and use of diethylstilboestrol (DES) (OR = 2.3; 95% CI 0.8, 6.4) appeared to be positively associated with breast cancer risk. The results from this study provide limited support for the hypothesis that in utero oestrogen exposure may be related to subsequent breast cancer risk among young women.

Electron-transfer mechanisms in photosensitization by the anti-inflammatory drug benzydamine.

The novel anti-inflammatory drug benzydamine has been show to photosensitize the reduction of Nitro Blue Tetrazolium, ferricytochrome c and copper (II) bathocuproinedisulphonate in aqueous solutions (pH 7.4, 30 degrees C) when irradiated with UV light at its maximum absorption wavelength of 308 nm. The reduction reactions all proceed most efficiently when the solutions are deoxygenated, clearly indicating that direct electron transfer occurs from the excited state of the sensitizer to the substrate. In aerated solutions the reduction reactions are slower and are partially inhibited by superoxide dismutase, suggesting that superoxide anion could be involved as an intermediate when oxygen is present. Benzydamine also photosensitizes the oxidation of 1-histidine and 2,5-dimethylfuran by the singlet oxygen pathway in aerated solutions. The ability of benzydamine to participate as sensitizer in several types of photochemical reaction is relevant to the observed clinical photosensitivity of the drug.

Dramatic changes in oxidative tryptophan metabolism along the kynurenine pathway in experimental cerebral and noncerebral malaria.

The pathogenesis of human cerebral malaria (CM) remains unresolved. In the most widely used murine model of CM, the presence of T lymphocytes and/or interferon (IFN)-gamma is a prerequisite. IFN-gamma is the key inducer of indoleamine 2,3-dioxygenase (IDO), which is the catalyst of the first, and rate-limiting, step in the metabolism of tryptophan (Trp) along the kynurenine (Kyn) pathway. Quinolinic acid (QA), a product of this pathway, is a neuro-excitotoxin, like glutamic acid (Glu) and aspartic acid (Asp). Kynurenic acid (KA), also produced from the Kyn pathway, antagonizes the neuro-excitotoxic effects of QA, Glu, and Asp. We therefore examined the possible roles of IDO, metabolites of the Kyn pathway, Glu, and Asp in the pathogenesis of fatal murine CM. Plasmodium berghei ANKA infection was studied on days 6 and 7 post-inoculation (p.i.), at which time the mice exhibited cerebral symptoms such as convulsions, ataxia, coma, and a positive Wooly/White sign and died within 24 hours. A model for noncerebral malaria (NCM), P. berghei K173 infection, was also studied on days 6 and 7 and 13 to 17 p.i. to examine whether any changes were a general response to malaria infection. Biochemical analyses were done by high-pressure liquid chromatography and gas chromatography/mass spectrometry/mass spectrometry (GC/MS/MS). IDO activity was low or absent in the brains of uninfected mice and NCM mice (days 6 and 7 p.i.) and was induced strongly in the brains of fatal murine CM mice (days 6 and 7 p.i.) and NCM animals (days 13 to 17 p.i.). This induction was inhibited greatly by administration of dexamethasone, a treatment that also prevented CM symptoms and death. Furthermore, IDO induction was absent in IFN-gamma gene knockout mice, which were also resistant to CM. Brain concentrations of Kyn, 3-hydroxykynurenine, and the neuro-excitotoxin QA were significantly increased in both CM mice on days 6 and 7 p.i. and NCM mice on days 13 to 17 p.i., whereas an increase in the ratio of brain QA to KA occurred only in the CM mice at the time they were exhibiting cerebral symptoms. Brain concentrations of Glu and Asp were significantly decreased in CM and NCM mice (days 13 to 17 p.i.). The results imply that neuro-excitation induced by QA may contribute to the convulsions and neuro-excitatory signs observed in CM.

Validity and reliability of subject and mother reporting of perinatal factors.

The authors used data from a population-based case-control study of breast cancer in women aged < or = 44 years (cases, n = 975; controls, n = 866) conducted between 1994 and 1996 in three counties of western Washington state to assess the validity and reliability of reported perinatal factors. For a sample of participants, exposure information from self-administered questionnaires was validated with information from birth certificates (cases, n = 378; controls, n = 283). Detailed information regarding perinatal characteristics of their daughters was also collected from subjects' mothers (case mothers, n = 510; control mothers, n = 436) to assess the reliability of subjects' reporting of these events. Although reporting of birth weight by subjects (cases, r = 0.83; controls, r = 0.80) and their mothers (case mothers, r = 0.89; control mothers, r = 0.84) was highly correlated with the birth certificates, there was differential measurement error by subjects; cases reported birth weight accurately on average, but controls tended to underestimate their birth weight. Agreement between the subject and mother report was excellent for birth weight (cases, r = 0.85; controls, r = 0.87) and good for other perinatal factors, but birth order and maternal diethylstilbestrol use were underreported among cases and reported accurately among controls. Differential measurement error of birth weight by case-control status resulted in biased odds ratios for breast cancer risk.

Utility of follicle stimulating hormone (FSH), luteinizing hormone (LH), oestradiol and FSH:LH ratio in predicting reproductive age in normal women.

The relative efficacy of follicle stimulating hormone (FSH), luteinizing hormone (LH), FSH:LH ratio and oestradiol is evaluated as a predictor of ovarian reserve (reproductive age) in normal women. Serum levels of FSH, LH, oestradiol and FSH:LH ratios were measured during menstrual cycle days 1-4 in younger (20-25 years; n = 23) and older (40-45 years; n = 32) reproductive age women with regular menstruation and normal reproductive function. On days 1-4, mean levels of FSH, oestradiol and FSH:LH ratios were significantly higher in older compared with younger women. FSH increased in concentration across cycle days in both age groups. A significantly lower LH value in younger versus older women was found only on day 1. Oestradiol showed no change across days in the younger group, but increased significantly from day 1 to day 4 in the older group. FSH values on days 1 or 2 were the best single predictor of age differences. However, the best prediction of age differences was obtained by using the combination of FSH and LH (as opposed to the FSH:LH ratio) on day 1 of the menstrual cycle.

Photosensitizing activity of the anti-bacterial drugs sulfamethoxazole and trimethoprim.

The photochemical reactions in vitro of sulfamethoxazole alone and in combination with trimethoprim were studied to obtain information on the photosensitization mechanism. Sulfamethoxazole in aqueous solution, on exposure to UVB radiation, generates free radicals and singlet oxygen, with the neutral molecule being at least twice as active as the sulfamethoxazole anion. Photoexcited sulfamethoxazole can participate in electron transfer to cytochrome-c and nitro blue tetrazolium, and sensitizes the peroxidation of linoleic acid and the hemolysis of human erythrocytes, predominantly by a free radical mechanism. Trimethoprim is relatively inactive in the same photochemical systems.

Evaluation of amperometric detection for the liquid-chromatographic determination of tetracycline antibiotics and their common contaminants in pharmaceutical formulations.

A sensitive high-performance liquid chromatographic technique with amperometric detection has been developed for the determination of seven commercially used tetracyclines in bulk powders and pharmaceutical preparations. The technique is based on the oxidation of these compounds and their contaminants at the glassy carbon electrode. The extraction procedures are simple and the HPLC conditions separate the tetracyclines from their major degradation products. The chromatography was performed using a commercially available octadecylsilane column, with a mobile phase: KH2 PO4 (pH = 2.5; 0.05 M) - acetonitrile (84:16, v/v) and detection at 1.2 V. The technique permits the simultaneous determination of trace amounts of chlortetracycline, demeclocycline, doxycycline, methacycline, minocycline, oxytetracycline and tetracycline as well as the separation of their common impurities (epi, anhydro and epianhydro contaminants) with detection limits of 0.1-1.0 ng microl(-1) and recoveries of 99.1-100.4%. No interference was observed from the commonly present excipients in pharmaceutical formulations.

Reactions of non-steroidal anti-inflammatory drugs with polyacrylamide free radicals.

The free radical reactivity of a number of currently prescribed non-steroidal anti-inflammatory drugs (NSAIDs) (sulindac, diflunisal, piroxicam, naproxen, ibuprofen, indomethacin and aspirin) was studied by observing their action on the free radical polymerization of acrylamide initiated by the thermal decomposition of potassium peroxodisulfate in aqueous solution at pH 7 and 50°C. Analysis of the kinetics of the polymerization reaction showed that sulindac, diflunisal, piroxicam, indomethacin and aspirin reacted directly with the carbon-centred polyacrylamide free radicals, thereby retarding the polymerization. The specific rate constants for reaction of sulindac, diflunisal, piroxicam, indomethacin and aspirin with polyacrylamide radicals at pH 7, ionic strength 0.1 M and 50°C were found to be 6850, 262, 76, 30 and 21 M(-1) s(-1) respectively. The reaction mechanism is postulated to involve reduction of the drug. On the other hand, naproxen and ibuprofen were able to react with the initiating SO4(•-) radicals, causing inhibition of the polymerization and oxidation of the drug. This study verifies the ability of NSAIDs to react as free radical scavengers and potentially to participate as a chain breaking agent in 'oxidative stress' in biological systems. Among them, sulindac is the most selective and effective when interacting with the carbon-centred radicals, and this may be a reflection of the rapid reduction in vivo of sulindac to its active sulphide metabolite.

Separation and characterization of cholesteryl oxo- and hydroxy-linoleate isolated from human atherosclerotic plaque.

In previous work we demonstrated that up to 30% of cholesteryl linoleate in homogenates of advanced human plaque samples is present in oxidized forms. Here we show that the material from plaque hexane extracts which co-elutes with cholesteryl hydroxy-linoleate on reversed phase HPLC (Anal Biochem 1993;213:79), is composed of several isomers of cholesteryl hydroxy- and cholesteryl oxo-octadecadienoate. Enzymatic hydrolysis and measurement of liberated cholesterol and disappearance of the esters revealed that almost all of the material consisted of unoxidized cholesterol esterified to oxidized derivatives of octadecadienoate. Semi-preparative reversed-phase HPLC was used to obtain sufficient quantities of this co-eluting material to undertake normal phase HPLC separation of these components. The nature of such separated and isolated compounds was identified, by co-chromatography with authentic standards, UV spectroscopy and chemical ionization and electron impact mass spectrometry, as cholesteryl hydroxy- and cholesteryl oxo-octadecadienoate. These oxidized fatty acids have been observed previously in plaque, in agreement with our new unambiguous demonstration of their presence as cholesteryl esters. The application of the methods described for the separation of the various forms of oxidized cholesteryl octadecadienoate may aid mechanistic studies of in vitro and in vivo lipoprotein lipid oxidation.

Biological and lifestyle factors, and lipid and lipoprotein levels among Japanese Americans in Seattle and Japanese men in Japan.

BACKGROUND: It has been previously shown that Japanese Americans in Seattle have significantly higher cholesterol levels than native Japanese. The present study examines the association of biological and lifestyle factors with plasma lipid and lipoprotein levels among Japanese Americans (JA) and native Japanese (NJ) to determine if these associations are consistent between these high and low cholesterol populations. METHODS: Study samples consisted of 710 JA male and 728 JA female volunteers living in the Seattle area and a random sample of 3833 NJ male urban workers who participated in parallel cardiovascular disease screening and lifestyle surveys for 1989-1994. Multiple regression analysis was conducted to examine the association of lifestyle and biological factors with lipid and lipoprotein levels. RESULTS: Alcohol consumption was positively and linearly associated with high density lipoprotein cholesterol (HDL-C) levels and negatively associated with both low density lipoprotein cholesterol (LDL-C) levels and the ratio of total cholesterol (TC)/HDL-C (P < 0.05 to P < 0.001) among JA males and JA females and NJ males. Current smoking habit was observed to be negatively associated with HDL-C levels and positively with TC/HDL-C ratio and log TG levels (logarithmic transformation of triglyceride values) (P < 0.05 to P < 0.001) among all three groups. Body mass index (BMI) was negatively associated with HDL-C levels and positively associated with log TG and TC/HDL-C ratio among all three groups (P < 0.05 to P < 0.001). Moderate alcohol consumption was negatively associated with log TG levels among JA males and females (P < 0.05), whereas heavy alcohol consumption was positively associated with log TG levels in NJ males (P < 0.001). Smoking was positively associated with TC and LDL-C levels (P < 0.05) among JA males, whereas a negative association (P < 0.05) was observed in NJ males. CONCLUSION: Overall, the fitted models were consistent between JA males and females and NJ males with the exception of smoking on TC and LDL-C. The results suggest that moderate alcohol consumption favourably influences lipid profiles in both high and low cholesterol populations. The results also indicate that light alcohol consumption is associated with decreased triglyceride levels, whereas heavy alcohol consumption is associated with increased triglyceride levels.