Identification and quantitation of phenylethylene glycol in human and rat urine, and its elevation in phenylketonuria

Phenylethylene glycol has been identified in rat and human urine using gas chromatography/chemical ionization/mass spectrometry. A method was developed for the quantitative analysis in urine of this phenylalanine metabolite and of p-hydroxyphenylethanol, a metabolite of tyrosine, by converting them to the pentafluoropropionyl derivatives and measuring them by selected ion monitoring. In human urine, about 90% of the phenylethylene glycol was present in a conjugated form (releasable by glusulase), but the reverse was true for rat urine, with about 90% being present in the unconjugated form. The excretion of free phenylethylene glycol (expressed as ng/mg creatinine) was 2.7-fold higher in a group of untreated phenylketonuric patients than in the control group, but the phenylketonuric patients excreted abnormally low amounts of 3-methoxy-4-hydroxyphenylethylene glycol. Intraperitoneal injections of L-phenylalanine in rats resulted in a small increase in the excretion of phenylethylene glycol. On the other hand, the injection of phenylethanolamine resulted in an 82-fold increase in the excretion of phenylethylene glycol, but phenylethylamine had no effect. These results indicate that the conversion of phenylethylamine to phenylethanolamine is the rate limiting step in this metabolic pathway.     

The interaction between polymerization initiators and inhibitors in solutions. 1. The reaction of benzoyl peroxide with p-benzoquinone in dilute solutions in chlorobenzene

The reaction of benzoyl peroxide with p-benzoquinone in dilute solutions in chlorobenzene was investigated by isolation and identification of some of the reaction products. The reaction is complex; the identified products were phenyl benzoquinone, benzoyloxy benzoquinone, quinhydrone of p-benzoquinone, benzoic acid, and chlorobiphenyls. There was a considerable amount of tarry quinoid products of unspecific physical properties. Neither simple disubstituted quinoid products, nor mono- or di-ethers of hydroquinone were detected. A mechanism based on these findings has been suggested for the reaction.     

Effect of glutamine on preimplantation mouse embryo development in vitro

OBJECTIVES: The purpose of this research was to study the independent effect of the amino acid glutamine on preimplantation mouse embryo development in vitro. STUDY DESIGN: Two-cell stage mouse embryos were cultured in human tubal fluid medium in the presence and absence of 1 mmol/L of glutamine. Outcomes for morphology and cleavage rates were compared with Fisher's and Mann-Whitney's tests, respectively. RESULTS: Glutamine increased the proportion of embryos that developed to the blastocyst stage (86.4%) compared with those cultured without glutamine (59.1%) (P =.052). The percentages of embryos developing to the morula or hatching blastocyst stages were comparable in the 2 groups. Blastocyst total cell numbers were significantly higher in the glutamine group (34+/-1.7 vs 18.5+/-3.5, respectively; values are mean+/-SEM, P =.044). CONCLUSION: The amino acid glutamine independently improves preimplantation mouse embryo development in vitro. Further studies are needed to examine the applicability of these results to humans.     

Central neurocytoma. Four patients

We report four cases of central neurocytoma we operated on at our institution, between 1994 and 2002. This uncommon lesion occurred in young patients, was located in the lateral ventricules and was revealed by signs of intracranial hypertension. The tumor was totally removed in three cases and subtotally in one. Immunohistochemistry provided useful information to distinguish neurocytoma from other nervous system tumors. Prognosis was excellent in two patients. One patient developed tumor recurrence seven years after surgery, without any progression on further follow up evaluation. In the last patient, the tumor showed a more aggressive progression requiring the adjunction of radiosurgery.     

Analysis of failures after vascularized fibular grafting in femoral head necrosis

Evaluation of graft-host bone interactions after failed vascularized fibular grafting of femoral head necrosis may elucidate the reasons for failure of the procedure. According to the authors' study, the vascularized fibula implanted into the femoral head before collapse has the potential for restructuring the major segment of the affected head and delaying joint degeneration for many years if circumferential graft-host union is established.Asymmetric bone healing and non-union between the graft and the necrotic subchondral bone in the weight-bearing area lead to failure, progression of symptoms, and subsequent early hip replacement.     

The pharmacokinetics of equoral versus neoral in stable renal transplant patients: a multinational multicenter study

We studied the pharmacokinetics (PKs) of the new generic cyclosporine formulation, Equoral capsules, after the switch from original formulation Neoral capsules in stable renal transplant patients. The study was carried out in accordance with the basic principles defined in the US 21 CFR Part 312.20 and the principles of the Declaration of Helsinki. The study included clinically stable first renal transplant patients maintained on cyclosporine with no rejection episode during the past 6 months. Hematology, biochemistry, and urine chemistry were determined on day 7, and day 21. The patients were all switched to Neoral (lot number 416MFD0601) on day 0 when the first sparse sampling PK was performed. On day 14 a 12-hour PK profile included predose, 30 minutes; 1 hour; 1 hour 30 minutes; 2 hours; 3 hours; 4 hours; 5 hours; 6 hours; 8 hours; 10-hours and 12-hour samples. Cyclosporine levels were determined using a CYA kit (Abbott TDx). On day 15 the patients were switched from Neoral capsules to Equoral capsules (lot 5T111014) at an equivalent dosage (mg/mg). The second sparse sampling PK was performed on day 21 and a 12-hour PK was performed on day 28. On the morning of day 29 patients were switched from Equoral capsules to Neoral capsules at an equivalent dosage (mg/mg). Additional concentrations were measured on days -7, 18, and 35. Safety parameters were monitored at each visit. The pharmacokinetics of both formulations were equivalent. The mean AUC for Neoral and Equoral was 2856 and 2892, respectively. The ratios of LSM and the 90% confidence intervals for the in-transformed parameters (AUC o-t, AUC inf, and Cmax) of Equoral and Neoral SGC were 98% and 95%, respectively, suggesting that Equoral and Neoral SGC are bioequivalent.     

Obstetric outcome of excessively overgrown fetuses (> or = 5000 g): a case-control study

AIMS: To compare the obstetric outcome of excessively- and appropriately-grown fetuses. METHODS: Medical records of mothers who delivered excessively overgrown fetuses, defined as birthweight > or = 5000 g, in our hospital between 1996 and 2000 (n = 47, study group), and a control group who delivered fetuses with normal birthweight (n = 47) were reviewed. RESULTS: Incidence of excessively overgrown fetuses was 0.24% and 68% were boys. Mothers in this group were significantly older, overweight and multiparous (p < 0.0001) and had gestational diabetes mellitus (p < 0.0001) and prolonged pregnancies (p = 0.04). A previous big baby was also significant (p < 0.0001) and the commonest risk factor. There were no obvious risk factors in nine (19.1%) cases. More than half (n = 28, 59.5%) of these babies were delivered vaginally without clinical suspicion of excessive fetal size. Duration of second stage of labor and incidence of maternal trauma were similar in both groups. Cesarean delivery (p = 0.0003), postpartum hemorrhage (p = 0.004), birth asphyxia (p = 0.007), shoulder dystocia (p < 0.0001) and fetal trauma (p = 0.03) were significantly more frequent in the study group. CONCLUSIONS: Excessively overgrown fetuses are associated with the same risk factors as fetal macrosomia and should be delivered by cesarean if diagnosed antenatally because of increased maternal and perinatal morbidity during vaginal delivery.     

Women's perceptions of and experiences with medical student involvement in outpatient obstetric and gynecologic care in the United Arab Emirates

OBJECTIVE: The purpose of this study was to determine the experiences, satisfaction, and comfort of women with medical student participation in outpatient care during obstetric and gynecology clerkships. STUDY DESIGN: A consecutive sample of 303 women who attended the clinic were interviewed before consultation; a structured questionnaire was used. RESULTS: Two hundred sixty-four women (87.1%) accepted student involvement; 158 women (59.8%) and 173 women (66.5%), respectively, preferred female students or preceptors. Comfort levels were significantly lower with male students or preceptors in all skills that were tested (P <.0001), particularly pelvic examination and the discussion of sexual problems. Acceptance was associated significantly with older age (P <.0001), higher parity (P <.0001), higher education (P =.002), husband's occupation (P =.006), obstetric consultation (P <.0001), previous teaching encounters (P =.0006), recognition of the students' roles (P =.004), and satisfaction with clinical service (P = 0.01). Reasons for nonacceptance (n = 39 women, 12.9%) were concern about privacy during examination (53.8%) or counseling (25.6%) and the extent of the students' involvement (20.5%). CONCLUSION: Most women agreed to participate in the teaching of obstetric and gynecologic skills to medical students.     

Exploring perceptions and attitudes of senior medical students and interns to academic integrity

CONTEXT: Academic integrity is fundamental to the role of aspiring doctors. However, little is known about Middle Eastern students' perceptions and experiences of educational dishonesty. PURPOSE: To describe the self-reported attitudes and behaviours of senior medical students and interns regarding educational integrity and to determine whether there are any differences according to gender and year of study. DESIGN: Cross-sectional study using a self-administered questionnaire to 88 participants. SETTING: Faculty of Medicine and Health Sciences, United Arab Emirates University, Al-Ain, UAE. RESULTS: A total of 82 (93.2%) respondents considered educational misconduct to be wrong. A total of 78 (88.6%) participants would not engage in such activities. Unethical educational practices such as plagiarism were viewed less seriously than other aspects of educational misconduct such as misuse of power. Female students were significantly less likely than males to report that they would engage in dishonest educational practices (P = 0.04). Interns were more stringent than medical students regarding penalties appropriate for academic misconduct (P = 0.002). Only 13 (15%) subjects stated that they would inform faculty of dishonest behaviour on the part of their peers. CONCLUSION: Most participants, particularly females and interns, consider educational misconduct to be wrong and would not engage in such activities.