Duplication Xp11.22-p14 in females: does X-inactivation help in assessing their significance?

In females, large duplications in Xp often lead to preferential inactivation of the aberrant X chromosome and a normal phenotype. Recently, a recurrent ∼4.5 Mb microduplication of Xp11.22-p11.23 was found in females with developmental delay/intellectual disability and other neurodevelopmental disorders (speech development disorder, epilepsy or EEG anomalies, autism spectrum disorder, or behavioral disorder). Unexpectedly, most of them showed preferential inactivation of the normal X chromosome. We describe five female patients carrying de novo Xp duplications encompassing p11.23. Patient 1 carried the recurrent microduplication Xp11.22-p11.23, her phenotype and X-chromosome inactivation (XI) pattern was consistent with previous reports. The other four patients had novel Xp duplications. Two were monozygotic twins with a similar phenotype to Patient 1 and unfavorable XI skewing carrying an overlapping ∼5 Mb duplication of Xp11.23-p11.3. Patient 4 showed a duplication of ∼5.5 Mb comparable to the twins but had a more severe phenotype and unskewed XI. Patient 5 had a ∼8.5 Mb duplication Xp11.23-p11.4 and presented with mild ID, epilepsy, behavioral problems, and inconsistent results of XI analysis. A comparison of phenotype, size and location of the duplications and XI patterns in Patients 1-5 and previously reported females with overlapping duplications provides further evidence that microduplications encompassing Xp11.23 are associated with ID and other neurodevelopmental disorders in females. To further assess the implication of XI for female carriers, we recommend systematic analysis of XI pattern in any female with X imbalances that are known or suspected to be pathogenic.

Improved GMP-compliant multi-dose production and quality control of 6-[18F]fluoro-L-DOPA

Background

6-[¹⁸F]Fluoro-L-3,4-dihydroxyphenylalanine (FDOPA) is a frequently used radiopharmaceutical for detecting neuroendocrine and brain tumors and for the differential diagnosis of Parkinson’s disease. To meet the demand for FDOPA, a high-yield GMP-compliant production method is required. Therefore, this study aimed to improve the FDOPA production and quality control procedures to enable distribution of the radiopharmaceutical over distances.

FDOPA was prepared by electrophilic fluorination of the trimethylstannyl precursor with [¹⁸F]F₂, produced from [¹⁸O]₂ via the double-shoot approach, leading to FDOPA with higher specific activity as compared to FDOPA which was synthesized, using [¹⁸F]F₂ produced from ²⁰Ne, leading to FDOPA with a lower specific activity. The quality control of the product was performed using a validated UPLC system and compared with quality control with a conventional HPLC system. Impurities were identified using UPLC-MS.

Results

The [¹⁸O]₂ double-shoot radionuclide production method yielded significantly more [¹⁸F]F₂ with less carrier F₂ than the conventional method starting from ²⁰Ne. After adjustment of radiolabeling parameters substantially higher amounts of FDOPA with higher specific activity could be obtained. Quality control by UPLC was much faster and detected more side-products than HPLC. UPLC-MS showed that the most important side-product was FDOPA-quinone, rather than 6-hydroxydopa as suggested by the European Pharmacopoeia.

Conclusion

The production and quality control of FDOPA were significantly improved by introducing the [¹⁸O]₂ double-shoot radionuclide production method, and product analysis by UPLC, respectively. As a result, FDOPA is now routinely available for clinical practice and for distribution over distances.

Disruption of SOX6 is associated with a rapid-onset dopa-responsive movement disorder, delayed development, and dysmorphic features

BACKGROUND

Sox6 is a transcription factor that is crucial for the differentiation and development of cortical interneurons and dopaminergic neurons of the substantia nigra pars compact. Loss-of-function mutations might thus result in complex paroxysmal diseases such as epilepsy syndromes or movement disorders.

PATIENT

We present a 15-year-old boy with delayed speech development and attention deficit hyperactivity disorder who presented with a rapid-onset generalized dopa-responsive dystonia.

RESULTS

Neurological examination revealed generalized dystonic and frequent athetoid movements of the arms, trunk, and neck. Gait was severely impaired secondary to frequent dystonic postures. Both a resting tremor and action tremors were observed in both hands. Speech was dysarthric but language comprehension was unimpaired. Testing for saccadic dysfunction revealed hypometric horizontal and vertical saccades. Physical examination was otherwise significant for a pectus carinatum and splenomegaly. Laboratory studies, brain magnetic resonance imaging, and electroencephalography were unremarkable. Treatment with levodopa/carbidopa led to a complete and sustained remission of neurological symptoms. Genetic testing revealed a mono-allelic de novo 84-kb deletion on chromosome 11p15.2 encompassing exons 14-16 of the SOX6 gene (chr11: 15944880-16029095, NCBI 37/hg19).

CONCLUSIONS

This is the first report of a dopa-responsive movement disorder associated with SOX6 disruption. SOX6 mutations should be considered in the differential diagnosis of unexplained dopa-responsive dystonia syndromes.

Characterization of large deletions in the DHCR7 gene

Pathogenic variants in the DHCR7 gene cause Smith-Lemli-Opitz syndrome (SLOS), a defect of cholesterol biosynthesis resulting in an autosomal recessive congenital metabolic malformation disorder. In approximately 4% of patients, the second mutation remains unidentified. In this study, 12 SLOS patients diagnosed clinically and/or by elevated 7-dehydrocholesterol (7-DHC) have been investigated by customized multiplex ligation-dependent probe amplification (MLPA) analysis, because only one DHCR7 sequence variant has been detected. Two unrelated patients of this cohort carry different large deletions in the DHCR7 gene. One patient showed a deletion of exons 3-6. The second patient has a deletion of exons 1 and 2 (non-coding) and lacks the major part of the promoter. These two patients show typical clinical and biochemical phenotypes of SLOS. Second disease-causing mutations are p.(Arg352Trp) and p.(Thr93Met), respectively. Deletion breakpoints were characterized successfully in both cases. Such large deletions are rare in the DHCR7 gene but will resolve some of the patients in whom a second mutation has not been detected.

Mosaic deletion of EXOC6B: further evidence for an important role of the exocyst complex in the pathogenesis of intellectual disability

We describe a boy with developmental delay, speech delay, and minor dysmorphic features with a heterozygous de novo ∼460 kb deletion at 2p13.2 involving only parts of EXOC6B present in about 50% of lymphocytes. This widely expressed gene encodes the exocyst component 6B, which is part of a multiprotein complex required for targeted exocytosis. Little is known about the effect of EXOC6B haploinsufficiency. In 2008, a patient with a complex syndromic phenotype, including left renal agenesis, neutropenia, recurrent pulmonary infections, long bone diaphysis broadening, growth retardation, and developmental delay (DD) was found to carry a de novo translocation t(2;7) involving TSN3 and EXOC6B. Further characterization of the translocation indicated that disruption of TSN3 may be responsible for the skeletal phenotype. Recently, a heterozygous deletion of EXOC6B along with a deletion of the CYP26B1 gene has been reported in a boy with intellectual disability, speech delay, hyperactivity, facial asymmetry, a dysplastic ear, brachycephaly, and mild joint contractures. Additionally, disruption of EXOC6B by a de novo balanced translocation t(2;8) has been described in a patient with developmental delay, epilepsy, autistic and aggressive behavior. This is the first report of a de novo deletion affecting only EXOC6B in an individual with developmental delay. In conclusion, based on our findings and recent data from the literature, there is evidence that EXOC6B and the exocyst complex might play an important role in the molecular pathogenesis of intellectual disability.

Characterization of the first intragenic SATB2 duplication in a girl with intellectual disability, nearly absent speech and suspected hypodontia

SATB2, a gene encoding a highly conserved DNA-binding protein, is known to have an important role in craniofacial and neuronal development. Only a few patients with SATB2 variants have been described so far. Recently, Döcker et al provided a summary of these patients and delineated the SAS (SATB2-associated syndrome). We here report on a girl with intellectual disability, nearly absent speech and suspected hypodontia who was shown to carry an intragenic SATB2 tandem duplication hypothesized to lead to haploinsufficiency of SATB2. Preliminary information on this patient had already been included in the article by Döcker et al. We want to give a detailed description of the patient's phenotype and genotype, providing further insight into the spectrum of the molecular mechanisms leading to SAS.

The phenotypic spectrum of duplication 5q35.2-q35.3 encompassing NSD1: is it really a reversed Sotos syndrome?

Loss-of-function mutations of NSD1 and 5q35 microdeletions encompassing NSD1 are a major cause of Sotos syndrome (Sos), which is characterized by overgrowth, macrocephaly, characteristic facies, and variable intellectual disability (ID). Microduplications of 5q35.2-q35.3 including NSD1 have been reported in only five patients so far and described clinically as a reversed Sos resulting from a hypothetical gene dosage effect of NSD1. Here, we report on nine patients from five families with interstitial duplication 5q35 including NSD1 detected by molecular karyotyping. The clinical features of all 14 individuals are reviewed. Patients with microduplications including NSD1 appear to have a consistent phenotype consisting of short stature, microcephaly, learning disability or mild to moderate ID, and distinctive facial features comprising periorbital fullness, short palpebral fissures, a long nose with broad or long nasal tip, a smooth philtrum and a thin upper lip vermilion. Behavioral problems, ocular and minor hand anomalies may be associated. Based on our findings, we discuss the possible etiology and conclude that it is possible, but so far unproven, that a gene dosage effect of NSD1 may be the major cause.

An improved method for the preparation of [11C]verapamil

This paper describes an improved preparation of [11C]verapamil by reaction of [11C]methyl triflate with desmethylverapamil. The optimal reaction temperature, amount of precursor and reaction time were assessed. With this method [11C]verapamil can be prepared with a reproducible radiochemical yield of 66 +/- 4% (EOB, based on [11C]methyltriflate). Total synthesis time was 60 min. Radiochemical purity was >99% and specific activities varied between 5 and 30TBq/mmol.

Synthesis and evaluation of radiolabeled antagonists for imaging of beta-adrenoceptors in the brain with PET

Five potent, lipophilic beta-adrenoceptor antagonists (carvedilol, pindolol, toliprolol and fluorinated analogs of bupranolol and penbutolol) were labeled with either carbon-11 or fluorine-18 and evaluated for cerebral beta-adrenoceptor imaging in experimental animals. The standard radioligand for autoradiography of beta-adrenoceptors, [125I]-iodocyanopindolol, was also included in this survey. All compounds showed either very low uptake in rat brain or a regional distribution that was not related to beta-adrenoceptors, whereas some ligands did display specific binding in heart and lungs. Apparently, the criteria of a high affinity and a moderately high lipophilicity were insufficient to predict the suitability of beta-adrenergic antagonists for visualization of beta-adrenoceptors in the central nervous system.

Early transvaginal ultrasonography versus early cerclage in women with an unclear history of incompetent cervix

OBJECTIVE

Our aim was to compare outcomes in women with a questionable history of incompetent cervix, followed up with early transvaginal ultrasonography, with outcomes in women who had early cerclage.

STUDY DESIGN

Charts were reviewed and patients identified for incompetent cervix from our obstetric database from 1995 through 1997. We included women who had an unclear history of incompetent cervix as follows: second-trimester loss or termination, > or =3 first-trimester terminations, cone biopsy or loop electrosurgical excision, or exposure to diethylstilbestrol. The primary outcome variable was gestational age at delivery.

RESULTS

A total of 106 women were included, 45 in the early cerclage group and 61 in the early transvaginal ultrasonography group. The mean gestational age at delivery was 35.1 weeks for the early cerclage group versus 36.1 weeks for the early transvaginal ultrasonography group.

CONCLUSION

In women with an unclear history of incompetent cervix, early cerclage does not appear to offer significant benefit over early transvaginal ultrasonography.

A randomized comparison of transcervical Foley catheter to intravaginal misoprostol for preinduction cervical ripening

OBJECTIVE

To compare the efficacy of intravaginal misoprostol tablets with transcervical Foley catheter for preinduction cervical ripening.

METHODS

Pregnant women who presented for induction of labor with unfavorable cervices (Bishop score less than 6) were assigned randomly to intravaginal misoprostol (50 microg tablet every 4 hours for a maximum of six doses) or 30-mL Foley catheter placed transcervically with maintenance of traction.

RESULTS

Among 111 women, 53 were allocated to misoprostol and 58 to Foley bulb. Contractile abnormalities were more frequent in the misoprostol group (20.4%) than the Foley group (0%) (P <.001). No statistically significant differences were noted between groups in change in Bishop score, preinduction cervical ripening times, and total induction times. There were no statistically significant differences in mode of delivery or adverse neonatal outcomes. Uterine rupture occurred in one woman with two previous cesarean deliveries in the misoprostol group.

CONCLUSION

Intravaginal misoprostol and transcervical Foley catheter are equivalent for cervical ripening. Uterine contractile abnormalities and meconium passage are more common with misoprostol.

Impact of a pharmacist on drug costs in a coronary care unit

The impact of clinical pharmacy services on direct drug costs in a coronary care unit (CCU) was studied. An observational, nonrandomized study was conducted on all patients admitted to the CCU to evaluate the impact of clinical pharmacy services on direct drug costs. Clinical pharmacy services were introduced into the CCU in July 1998. Patient characteristics, mean drug costs per admission, mean drug category costs per admission, and total hospital costs per admission were determined for October 1997 to June 1998 (nonintervention period), July 1998 to March 1999 (intervention period 1), and April 1999 to December 1999 (intervention period 2). The Clini-Trend program was used to estimate the total reduction in drug costs associated with documented pharmacist interventions from January to December 1999. Mean patient age, sex, admitting diagnosis-related group, Medicare case-mix index, ventilator days, length of stay, and number of deaths did not differ significantly among the three study periods. Mean +/- S.D. drug costs per admission for the nonintervention period were $374.05 +/- $75.51. With the introduction of clinical pharmacy services, mean +/- S.D. drug costs per admission were $381.94 +/- $66.16 (p > 0.1 for intervention period 1 compared with the nonintervention period) and $233.74 +/- $84.16 (p = 0.002 for intervention period 2 compared with the nonintervention period). From January to December 1999, 4151 pharmacist interventions were documented. The estimated reduction in drug costs associated with the interventions totaled $372,384. A pharmacist's clinical services in the CCU allowed for significant estimated reductions in total drug costs.

Intracervical fibrin sealants: a potential treatment for early preterm premature rupture of the membranes

OBJECTIVE

We report our experience with a transvaginally applied intracervical fibrin sealant at <24 weeks' gestation.

STUDY DESIGN

This is an observational study of a referred patient population, with preterm premature rupture of the membranes at <24 weeks' gestation.

RESULTS

Twelve women consented to our protocol. The mean gestational age at preterm premature rupture of membranes was 19 weeks 4 days (range, 13-23 weeks); the mean gestational age at treatment was 20 weeks 5 days (range, 17-23 weeks). All women had a diminution in the amount of amniotic fluid leakage with an increase in amniotic fluid index. Among the 12 pregnancies (13 fetuses), there were 7 surviving neonates. Two women had apparent "resealing" of the membranes.

CONCLUSION

Fibrin sealants in midtrimester rupture of the membranes may lead to improved outcomes and now warrant formal evaluation.

The need for protein containing quality control materials for blood pH and electrolyte analyzers

In clinical chemistry quality control refers to monitoring of precision and accuracy of the performance of analytical methods. Calibration solutions and (matrixed) control solutions are used in transferring accuracy between definitive method, reference method and field methods. For this purpose aqueous (protein-free), protein-containing and serum-based types of quality control materials having different matrices are available. Here are presented differences in behaviour between aqueous (protein-free) and protein-containing materials. Potentiometry with an electrochemical cell is an often used field method to determine pH and activity of electrolytes with an Ion-Selective Electrode (ISE). Basically, measured e.m.f.'s of calibrators and sample are translated into the activity of the ionic species of the sample by means of the Nernst equation. Besides the standard e.m.f. (E(zero)) of the electrochemical system, the measured e.m.f. includes the ISE-membrane e.m.f. (EISE) and depends on electrolyte type and its concentration and Eij depends on the composition and geometry of the salt bridge. Both EISE and Eij depend on the sample matrix. Protein-containing samples cause a negative bias on the e.m.f. at the liquid junction and a positive bias at the ISE. When EISE and Eij are compared to the mV span of the reference interval, the effects are large for Ca2+, Na+ and Cl-. Exactly the same effects exist for H+, K+, Li+ and Mg2+ but the inaccuracy is less critical for these ions. It may be concluded that only protein containing controls can detect an error that occurs only with measurements on plasma specimens. In practice this means that calibration is checked with protein-free solutions, but that measurements in plasma are best checked with protein-containing solutions.

Evaluation of protein containing quality control materials for blood gas analysis

Protein containing quality control (QC) material in ampoules for blood gas, pH and electrolyte analysers has been manufactured using buffered protein (Bovine Serum Albumine, BSA) solution with sodium bicarbonate and chloride salts. For comparison a similar QC material but without protein was manufactured. Results obtained with ampouled QC material depend on pre-analytical effects, on matrix effects and on the stability of the material. Pre-analytical variation occurs with closed and/or opened ampoules. The shaking rate of the ampoule must be high (vortexing) and the duration of shaking long enough (15 seconds) to give good reproducibility. Temperature coefficients of protein containing controls are equal to those of protein free controls when incubated at different temperatures. Vigorously shaking of the ampoule gives a protein foam layer resulting in stable values for pH, pCO2 and pO2 during maximally 6 minutes after opening of the ampoule. Concerning matrix effects the CO2 buffer capacity of protein containing QC material is slightly higher compared to that of protein free QC materials as determined by tonometry with CO2/air gas mixtures and measuring pH and plotting log pCO2 vs. pH. The O2 buffer capacity measured as the bias on a properly functioning blood gas analyser is smaller than the bias of protein free QC material. The protein containing quality control is stable for at least 12 months when stored refrigerated at 2-6 degrees C and 28 days at room temperature.

Bat-eared fox behavioural ecology and the incidence of rabies in the Serengeti National Park

This paper provides a brief introduction into some aspects of bat-eared fox biology and social organization that is important to understanding rabies transmission and disease management in susceptible wildlife species (Macdonald 1980; 1993). A detailed description of the effects of two rabies outbreaks on a population of known individuals in the Serengeti National Park is given, Inter- and intrasexual differences in adult mortality rates are reported and discussed.

A comparative bioavailability study of carbamazepine tablets and a chewable tablet formulation

Differences in product formulations have been shown to affect the therapeutic response by altering the relative bioavailability and pharmacokinetics of a drug. The relative bioavailability and pharmacokinetics of carbamazepine tablets (CBZ) and a chewable tablet formulation were evaluated in 10 normal healthy subjects (five men and five women). The study utilized a randomized, crossover design with a 4-week washout period between doses. Blood samples were collected at 0, 1, 2, 3, 4, 6, 8, 10, 14, 24, 30, 36, and 48 h following a 200-mg dose. Plasma samples were assayed by fluorescence polarization immunoassay. Ke, Cmax, Tmax, area under the curve (AUC), and relative bioavailability were estimated using traditional pharmacokinetic methods and compared by paired t test. A statistically significant higher Cmax (3.81 +/- 81 vs. 4.64 +/- .80 mg/L) was observed with the chewable tablet formulation but was not thought to be clinically relevant. No significant differences between formulations for Ke (0.022 +/- 0.007 vs. 0.025 +/- 0.008 h-1 h), Tmax (7.49 +/- 2.69 vs. 6.04 +/- 2.7 h), AUC 48 h (119 +/- 22 vs. 133 +/- 13 mg/h/L), or AUCO--infinity ( 221 +/- 40 vs. 203 +/- 41 mg/h/L) were noted. Absorption was variable for both preparations. The relative bioavailability using the tablet as the standard formulation was (0.92 +/- 0.22). Transient, mild side effects were noted in three subjects with the chewable tablet alone, and one subject experienced side effects with both formulations. It was concluded that CBZ tablets and chewable tablets may be used interchangeably; however, considerable intra- and intersubject variability exists, and the need for patient monitoring is emphasized.

[Remission behavior following low-dose 13-cis-retinoic acid in papulopustular acne]

64 patients suffering from severe papulopustular acne previously resistant to therapy were treated with 13-cis retinoic acid (isotretinoin) at a dosage of 0.05, 0.1, or 0.2 mg/kg body weight for 20 weeks. After treatment, we performed follow-up examinations for 12 months concerning remission and side effects. After six months, more than half of the patients were free of relapses, even those treated with low doses, although there was a trend in favor of the 0.2 mg/kg body weight dose. According to lesion counts, the therapeutic effect of isotretinoin was even better after discontinuation of the drug. Mucocutaneous side effects disappeared within four to six weeks. In severe papulopustular acne, previously showing inadequate response to therapy, at least 0.2 mg/kg body weight isotretinoin should be given to ensure a good therapeutic result. These findings correspond with those observed in the initial reduction of lesions.

[13-cis-retinoic acid. Low dosage oral use in acne papulopustulosa. Results of a multicenter study]

Successful treatment of acne conglobata with 13-cis-retinoic acid (isotretinoin, Ro 4-3780) has already been reported in this journal [25, 36]. The aim of the present study was to treat severe forms of papulopustular acne, unresponsive to conventional therapy, with low doses of 13-cis-retinoic acid to obtain good results with few side effects. A total of 191 patients from 14 departments of dermatology in the Federal Republic of Germany received 13-cis-retinoic acid under open randomized conditions in parallel dose groups of 0.05, 0.1, and 0.2 mg/kg body weight for 20 weeks in order to establish efficacy and tolerance. All inflammatory and non-inflammatory skin lesions were counted. The intensity of seborrhea was graded by using a scale. Adverse effects as well as laboratory values were registered. After 20 weeks of treatment a 79% (0.05 mg), 80% (0.1 mg), and 84% (0.2 mg) decrease in the number of inflammatory skin lesions was seen. Fourteen patients in the lowest dose group were considered to be dropouts. The decrease in non-inflammatory skin lesions was less marked and amounted to between 49% and 69%. A significant reduction of seborrhea could be observed in all patients. The main side effect was dryness of the skin and mucous membranes, which was, however, of low intensity. The elevation of triglyceride and cholesterol levels reported with higher doses of 13-cis-acid, especially in patients with high-risk factors, were not encountered in this study.

[Hypacusis in acquired hypothyroidism (author's transl)]

We examined 56 patients with latent or clinical hypothyroidism and a control group of 18 patients with acute hypothyroidism. We were especially interested in the localization and extent of hearing abnormalities. 45% of the patients with chronic hypothyroidism showed a hearing loss. 2 of these patients had a pure conductive loss, 7 a combined hearing loss and 16 a sensorineural hearing loss. We demonstrated hair cell damage in 13 of the patients with chronic hypothyroidism. This loss was mild to moderate in over 90% of the cases. Although several patients had basilar-cochlear hearing losses, no characteristic audiograms could be found. 50% of the patients showed a small improvement in hearing after thyroid substitution therapy. The results of our examinations are discussed in detail.

[Hypacusis in acquired hypothyroidism (author's transl)]

We examined 56 patients with latent or clinically manifest hypothyroidism and 18 patients with acute athyreosis as a control group. We were especially interested in the localization and extent of hearing abnormalities. 45% of the patients with chronic hypothyroidism showed a hearing loss. Of these, two patients had a pure conductive loss, seven a combined hearing loss and 16 a sensori-neural hearing loss. We demonstrated hair cell damage in 13 of the patients with chronic hypothyroidism. The hearing loss was mild to moderate in over 90% of the cases. Although several patients had a basocochlear hearing loss, no characteristic audiogram was found. There was a correlation between the conductive loss and the severity of the hypothyroidism. 50% of the patients showed a significant improvement in hearing after substitution therapy. The results of our examinations are discussed in detail.