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Floating catalyst chemical vapor deposition (FC-CVD) methods offer a highly scalable strategy for single-step synthesis and assembly of carbon nanotubes (CNTs) into macroscopic textiles. However, the non-uniform axial temperature profile of a typical reactor, and differing precursor breakdown temperatures, result in a broad distribution of catalyst particle sizes. Spun CNT fibres therefore contain nanotubes with varying diameters and wall numbers. Herein, we describe a general FC-CVD approach to obtain relatively large yields of predominantly single-wall CNT fibres, irrespective of the growth promoter (usually a sulfur compound). By increasing carrier gas (hydrogen) flow rate beyond a threshold whilst maintaining a constant C : H2 mole ratio, CNTs with narrower diameters, a high degree of graphitization (G : D ratio ∼100) and a large throughput are produced, provided S : Fe ratio is sufficiently low. Analysis of the intense Raman radial breathing modes and asymmetric G bands, and a shift in the main nanotube population from thermogravimetric data, show that with increasing flow rate, the fibres are enriched with small diameter, metallic CNTs. Transmission electron microscopy corraborates our primary observation from Raman spectroscopy that with high total flow rates, the fibres produced consist of predominantly small diameter SWCNTs.

The unaddressed palliative care needs of patients with advanced, nonmalignant, lung disease highlight the urgent requirement for new models of care. This study describes a new integrated respiratory and palliative care service and examines outcomes from this service. The Advanced Lung Disease Service (ALDS) is a long-term, multidisciplinary, integrated service. In this single-group cohort study, demographic and prospective outcome data were collected over 4 years, with retrospective evaluation of unscheduled healthcare usage. Of 171 patients included, 97 (56.7%) were male with mean age 75.9 years and 142 (83.0%) had chronic obstructive pulmonary disease. ALDS patients had severely reduced pulmonary function (median (interquartile range (IQR)) forced expiratory volume in 1 s 0.8 (0.6-1.1) L and diffusing capacity of the lung for carbon monoxide 37.5 (29.0-48.0) % pred) and severe breathlessness. All patients received nonpharmacological breathlessness management education and 74 (43.3%) were prescribed morphine for breathlessness (median dose 9 mg·day -1 ). There was a 52.4% reduction in the mean number of emergency department respiratory presentations in the year after ALDS care commenced (p=0.007). 145 patients (84.8%) discussed and/or completed an advance care plan. 61 patients died, of whom only 15 (24.6%) died in an acute hospital bed. While this was a single-group cohort study, integrated respiratory and palliative care was associated with improved end-of-life care and reduced unscheduled healthcare usage., Competing Interests: Conflict of interest: Disclosures can be found alongside this article at openres.ersjournals.com

Floating catalyst chemical vapor deposition uniquely generates aligned carbon nanotube (CNT) textiles with individual CNT lengths magnitudes longer than competing processes, though hindered by impurities and intrinsic/extrinsic defects. We present a photonic-based post-process, particularly suited for these textiles, that selectively removes defective CNTs and other carbons not forming a threshold thermal pathway. In this method, a large diameter laser beam rasters across the surface of a partly aligned CNT textile in air, suspended from its ends. This results in brilliant, localized oxidation, where remaining material is an optically transparent film comprised of few-walled CNTs with profound and unique improvement in microstructure alignment and crystallinity. Raman spectroscopy shows substantial D peak suppression while preserving radial breathing modes. This increases the undoped, specific electrical conductivity at least an order of magnitude to beyond that of single-crystal graphite. Cryogenic conductivity measurements indicate intrinsic transport enhancement, opposed to simply removing nonconductive carbons/residual catalyst.

Objective: We aimed to analyse the effect of the introduction of fingolimod, the first oral disease-modifying therapy, on treatment utilisation and persistence in an international cohort of patients with multiple sclerosis (MS)., Methods: MSBASIS, a prospective, observational sub-study of the MSBase registry, collects demographic, clinical and paraclinical data on patients followed from MS onset (n=4718). We conducted a multivariable conditional risk set survival analysis to identify predictors of treatment discontinuation, and to assess if the introduction of fingolimod has altered treatment persistence., Results: A total of 2640 patients commenced immunomodulatory therapy. Following the introduction of fingolimod, patients were more likely to discontinue all other treatments (hazard ratio 1.64, p<0.001) while more patients switched to fingolimod than any other therapy (42.3% of switches). Patients switched to fingolimod due to convenience. Patients treated with fingolimod were less likely to discontinue treatment compared with other therapies (p<0.001). Female sex, country of residence, younger age, a high Expanded Disability Status Scale score and relapse activity were all independently associated with higher rates of treatment discontinuation., Conclusion: Following the availability of fingolimod, patients were more likely to discontinue injectable treatments. Those who switched to fingolimod were more likely to do so for convenience. Persistence was improved on fingolimod compared to other medications., (© The Author(s), 2015.)

An electromagnetic transmitter typically consists of individual components such as a waveguide, antenna, power supply, and an oscillator. In this communication we circumvent complications associated with connecting these individual components and instead combine them into a non-traditional, photonic enabled, compact transmitter device for tunable, ultrawide band (UWB) radiation. This device is a centimeter scale, continuous, thin film superconducting ring supporting a persistent super-current. An ultrafast laser pulse (required) illuminates the ring (either at a point or uniformly around the ring) and perturbs the super-current by the de-pairing and recombination of Cooper pairs. This generates a microwave pulse where both ring and laser pulse geometry dictates the radiated spectrum's shape. The transmitting device is self contained and completely isolated from conductive components that are observed to interfere with the generated signal. A rich spectrum is observed that extends beyond 30 GHz (equipment limited) and illustrates the complex super-current dynamics bridging optical, THz, and microwave wavelengths.

A phase hologram was machined on an optical fiber tip using a focused ion beam (FIB) system so that a ring-shaped beam emerges from the fiber tip. The fiber used for this work was a commercial single-mode optical fiber patch cable for a design wavelength of 633 nm with a germanosilicate core. The ring-shaped beam was chosen to ensure a simple geometry in the required phase hologram, though the Gerchberg-Saxton algorithm can be used to calculate a hologram for an arbitrary beam shape. The FIB machining took approximately 45 min at 30 kV and 200 pA. The radius of the resulting ring beam was 0.083 m at 1 m standoff, as compared to 0.1 m as was initially desired. Results suggest that this imaging technique may provide a basis for a beam-shaping method with several advantages over the current commercial solutions, having permanent alignment, compactness, and mechanical robustness. However, it would appear that minimizing the speckle pattern will remain a critical challenge for this technique to become widely implemented.

In Rett syndrome (RS), acute life-threatening episodes (ALTEs) are usually attributed to epilepsy or autonomic dysfunction but they can represent a movement disorder (MD). We describe three girls with RS who experienced ALTEs from an early age. These were long considered epileptic until video-EEG in Patients 1 and 3 revealed their non-epileptic nature. A primary dystonic mechanism was suspected and Patients 1 and 2 were treated with Trihexyphenidyl with significantly reduced frequency of the ALTEs. Patient 3 died before Trihexyphenidyl was tried. Trihexyphenidyl in RS patients with similar presentations can modify the dystonia and prevent ALTEs., ((c) 2009 Movement Disorder Society.)

Objective: To evaluate the mechanisms involved in the conduction to the scalp of anterior temporal epileptiform discharges in temporal lobe epilepsy., Methods: During electroencephalographic recordings extra electrodes were applied around the eyes and on the cheeks in 13 patients with anterior temporal discharges. The amplitude of at least 34 discharges per patient was compared., Results: Five hundred and twenty epileptiform discharges were studied. Among standard electrodes, most discharges from all patients were maximal at anterior temporal electrodes. They were always also seen over the ipsilateral outer canthus and inferior orbital electrodes with similar amplitudes, and with lower amplitudes at other ipsilateral facial electrodes (67.7-57.6%). Ipsilateral cheek and mid-temporal electrodes showed amplitudes within similar range (66.3-67.7%) despite being at different distance from the temporal lobes. At least 40% of discharges were also recorded by facial electrodes contralaterally to the hemisphere where discharges were largest ('cross over') with no clear latency difference., Conclusions: The topography of anterior temporal discharges is most readily explained by volume conduction through high conductivity skull foramina., Significance: The role of skull holes should be incorporated in EEG and possibly in MEG source localisation models and additional facial electrodes can be useful in the evaluation of bitemporal discharges in temporal lobe epilepsy.

RbAp46 and RbAp48 (pRB-associated proteins p46 and p48, also known as RBBP7 and RBBP4, respectively) are highly homologous histone chaperones that play key roles in establishing and maintaining chromatin structure. We report here the crystal structure of human RbAp46 bound to histone H4. RbAp46 folds into a seven-bladed beta propeller structure and binds histone H4 in a groove formed between an N-terminal alpha helix and an extended loop inserted into blade six. Surprisingly, histone H4 adopts a different conformation when interacting with RbAp46 than it does in either the nucleosome or in the complex with ASF1, another histone chaperone. Our structural and biochemical results suggest that when a histone H3/H4 dimer (or tetramer) binds to RbAp46 or RbAp48, helix 1 of histone H4 unfolds to interact with the histone chaperone. We discuss the implications of our findings for the assembly and function of RbAp46 and RbAp48 complexes.

Electrical impedance tomography (EIT) has the potential to produce images during epileptic seizures. This might improve the accuracy of the localization of epileptic foci in patients undergoing presurgical assessment for curative neurosurgery. It has already been shown that impedance increases by up to 22% during induced epileptic seizures in animal models, using cortical or implanted electrodes in controlled experiments. The purpose of this study was to determine if reproducible raw impedance changes and EIT images could be collected during epileptic seizures in patients who were undergoing observation with video-electroencephalography (EEG) telemetry as part of evaluation prior to neurosurgery to resect the region of brain causing the epilepsy. A secondary purpose was to develop an objective method for processing and evaluating data, as seizures arose at unpredictable times from a noisy baseline. Four-terminal impedance measurements from 258 combinations were collected continuously using 32 EEG scalp electrodes in 22 seizure episodes from 7 patients during their presurgical assessment together with the standard EEG recordings. A reliable method for defining the pre-seizure baseline and recording impedance data and EIT images was developed, in which EIT and EEG could be acquired simultaneously after filtering of EIT artefact from the EEG signal. Fluctuations of several per cent over minutes were observed in the baseline between seizures. During seizures, boundary voltage changes diverged with a standard deviation of 1-54% from the baseline. No reproducible changes with the expected time course of some tens of seconds and magnitude of about 0.1% could be reliably measured. This demonstrates that it is feasible to acquire EIT images in parallel with standard EEG during presurgical assessment but, unfortunately, expected EIT changes on the scalp of about 0.1% are swamped by much larger movement and systematic artefact. Nevertheless, EIT has the unique potential to provide invaluable neuroimaging data for this purpose and may still become possible with improvements in electrode design and instrumentation.

We report the occurrence of an unusually sustained, non-reactive, bilateral, rhythmic, subclinical discharge in a young adult without epileptic seizures

Proteins with R-CO-CO-NH- at the N-terminus, rather than the usual R-CH(-NH3+)-CO-NH-, are produced by non-enzymic transamination and also occur in the pyruvoyl enzymes. The oxoacyl group may be specifically removed from a model peptide, in yields of 70-80%, by treating them in 0.1 M phosphate buffer at 37 degreesC for 24 h with 25 mM of the N-phosphonomethyl derivative of phenylene-1,2-diamine. This provides mild conditions for the stepwise removal of N-terminal residues without denaturation.

The interaction of glutamate decarboxylase with the aspartate and glutamate analogues modified at C3 and C4 was studied. 3-Arsonoalanine, 3-phosphonoalanine, 2-amino-4-arsonobutyric acid, 2-amino-4-phosphonobutyric acid, a mixture of diastereoisomers of 4-(methylthio) glutamic acid and erythro-4-(methylthio) glutamic acid were shown to be poor substrates for the enzyme. Their decarboxylation was accompanied by transamination of the coenzyme (PLP) to pyridoxamine phosphate (PMP) which reversibly inactivated the enzyme. With arsonoalanine only part of PLP was converted into PMP and another part irreversibly formed a complex. 4-(Methylsulfonyl)-L-glutamic and 4-[(phenyl)(hydroxy)phosphoryl]-L-glutamic acids did not react with the glutamate decarboxylase.

The isosteric arsenical analogue of glycerol 3-phosphate, 3,4-dihydroxybutylarsonic acid, is a good substrate for rabbit muscle glycerol-3-phosphate dehydrogenase. Its oxidation is accompanied by release of arsenite. This release seems to be due to a spontaneous elimination of arsenite by 3-oxoalkylarsonic acids, as it is also observed in (1) the oxidation of 3-hydroxypropylarsonic acid by yeast alcohol dehydrogenase, (2) treatment of 3,4-dihydroxybutylarsonic acid with periodate and (3) nonenzymic transamination of the glutamate analogue 2-amino-4-arsonobutyric acid. Enzymic formation of 3-oxoalkylarsonic acids in cells can therefore be lethal, as arsenite is poisonous to most organisms because of its high affinity for dithiols such as dihydrolipoyl groups.

The interaction of glutamate decarboxylase with the aspartate analogues 3-arsonoalanine and 3-phosphonoalanine, with the glutamate analogues 2-amino-4-arsonobutyric acid and 2-amino-4-phosphonobutyric acid, and with 4-(methylthio)-L-glutamic acid, both as a mixture of diastereoisomers and as the (2S,4R)-form, was studied. All these analogues were poor substrates for the enzyme and only weak inhibitors. Their decarboxylation was accompanied by transamination of the enzyme-bound pyridoxal phosphate (PLP) to pyridoxamine phosphate (PMP), thus inactivating the decarboxylase. With arsonoalanine only part of the PLP was converted into PMP.

A compound containing the -PO3H2 group (phosphoric acid, one of its monoesters, or an alkylphosphonic acid) may be rapidly assayed by the decrease it produces in the absorbance at 450 nm of a buffered acidic solution of Fe3+ and N(-3) [corrected]. The method has been used to follow chromatograms of sugar phosphates and their phosphonomethyl analogues.

As part of our studies of the organization of the cat sacrocaudal spinal cord (S3-Ca7), the portion of the neuraxis that innervates the tail, we have begun to evaluate the behavioral effects of hemisection or complete transection at the level of Ca1. Clinical observations that the tail strongly deviated to the side of a hemisection indicated the presence of an ipsilateral hypertonia. After complete transection of the spinal cord, the tail became ventroflexed in a midline position and exhibited spasticity, i.e., hypertonia, hyperreflexia, and clonus. Bowel and bladder functions and hindlimb gait and reflexes remained intact following either lesion. Quantitative behavioral measures corroborated our clinical observations. With the tail tethered to a force transducer, tail muscle tone was measured after the tail was passively positioned. Following a transection, resistance to dorsiflexion of the tail was greater than resistance to ventroflexion. In addition, tonic deviation of the tail was documented with videotape analysis while cats walked on a plank. Normal cats walked with the tail sharply dorsiflexed and centered. In contrast, the tail deviated ipsilaterally in cats with a hemisection, and the tail was ventroflexed in cats with a transection. These observations indicate that the sacrocaudal spinal cord provides a model with special advantages for investigation of changes in segmental motor functions following spinal cord injury. The effects of lesions on the tail are quantifiable and can resemble that spasticity observed after spinal cord injury in humans. Importantly, minimal effects on locomotive and autonomic functions were observed following hemisection or transection of the sacrocaudal spinal cord.

We have investigated the organizational and morphological features of motoneurons from cat sacrocaudal spinal cord, the portion of the neuraxis that innervates the tail. This information is pertinent for development of a new model of spinal cord injury. An understanding of sacrocaudal circuitry is essential for physiological and behavioral assessment of the effects of sacrocaudal lesions. Observations from Nissl-stained sections corroborated Rexed's cytoarchitectural scheme. Putative motoneurons were located within two regions of the ventral horn: the ventromedial nucleus (lamina IX) and the nucleus commissuralis. To map motoneuron pools, cholera toxin-horseradish peroxidase conjugate was injected into each dorsal tail muscle. The dorsomedial muscle was innervated by ipsilateral nucleus commissuralis motoneurons. The dorsolateral and intertransversarius muscles were innervated by ipsilateral lamina IX and nucleus commissuralis motoneurons. Cell bodies of retrogradely labeled sacrocaudal motoneurons ranged from 22 to 82 microns in diameter; the unimodal distributions peaked between 45 and 50 microns. Dendritic trees of motoneurons, revealed by retrograde labeling or by intracellular injection with horseradish peroxidase, were extensive. Five to eight primary dendrites originated from the cell body. Dendritic branches extended throughout the ipsilateral ventral gray matter, with processes spreading into the surrounding white matter and the base of the dorsal horn. Dendrites from motoneurons with their soma in the lateral portion of lamina IX formed a longitudinal plexus at the gray/white border. Medial dendrites from motoneurons in the nucleus commissuralis formed bundles in the ventral gray commissure and spread throughout the contralateral ventral horn. It is speculated that contralateral dendrites subserve synchronized co-contraction of medial muscles from both sides of the tail.

Bromoacetylphosphonic acid, Br-CH2-CO-PO3H2, was made by brominating dimethyl acetylphosphonate and de-esterifying with HBr. It proves to be a powerful alkylating agent, reacting rapidly with GSH, with a rate constant of about 6M(-1).s(-1) at pH6.

Descending supraspinal and propriospinal neurons projecting to the female rat sacrocaudal spinal cord, the portion of the spinal cord that innervates the tail, were identified following injection of Fluoro-Gold into the S1-Ca2 spinal cord segments. This study attempted to determine anatomical substrates for propriospinal and supraspinal control of the tail. Propriospinal neurons were identified throughout laminae V-VIII and X at all levels of the spinal cord. The greatest density of labeling was in the lumbar enlargement, followed by the cervical enlargement, with least in the thoracic spinal cord. Within a given cord level, labeling was greatest within the intermediate zone. In addition, other prominent spinal cord collections included neurons in 1) lamina V of the lumbar enlargement, 2) dorsal lamina X of the cervical enlargement, and 3) the lateral spinal nucleus within the cervical enlargement. Supraspinal cells were identified within raphe nuclei, reticular formation nuclei, dorsal column nuclei, vestibular nuclei, noradrenergic groups, the red nucleus, the periaqueductal gray, the hypothalamus, and the motor cortex. These data indicate that there are significant descending projections to the sacrocaudal spinal cord, with distributions similar to those of other cord levels. Functionally, important supraspinal and propriospinal influences on tail, pelvic viscera and limbs, such as with locomotion, balance, defense, micturition, defecation, and sexual functions, may be mediated by these connections.

The terminal fields of primary afferent fibers from tail muscle spindle primary endings were mapped within cat sacrocaudal spinal cord (S3-Ca7), using intra-axonal recording and horseradish peroxidase staining techniques. We sought to determine the ipsilateral and contralateral projection patterns and to relate these to the fibers' muscles of origin. Fifty-three group Ia fibers were successfully stained. Segmental collaterals originated from either the ascending or descending branch within the dorsal columns. Collaterals coursed rostromedially within the dorsal columns and traversed the medial aspect of the dorsal horn. Ipsilateral terminations were similar for all fibers. Within the ventral horn, boutons were consistently observed in the medial or central portions of lamina VII. In lamina VIII, a variable number of boutons was seen on fine branches emerging from larger fibers coursing ventrally. Clusters of terminals were plentiful in the regions of motoneurons, i.e., lamina IX and the nucleus commissuralis. Terminals were found in the adjacent white matter. In addition to ipsilateral terminations, some group Ia fibers (20 of 53) had collateral branches that crossed ventrally to the central canal, terminating within the midline ventral gray commissure and/or the contralateral ventral horn. Crossed projections always originated in medial (dorsal or ventral), but not lateral, muscles of the tail. These data suggest that ipsilateral projections of group Ia fibers make connections on sacrocaudal motoneurons, on neurons mediating segmental reflex functions and on neurons conveying ascending information. It is speculated that crossed and uncrossed connections between group Ia fibers from medial muscles and bilateral dendritic trees of motoneurons subserve synchronized co-contraction of synergistic muscles located on the two sides of the body, such as with dorsal or ventral flexion of the tail. Group Ia projections from lateral muscles, that are entirely ipsilateral, would be involved with lateral movements of the tail.

Acylphosphonic acids, R-CO-PO(OH)2, have been synthesized by the steps [formula: see text] of which the last is new and provides a mild method for de-esterifying acylphosphonic acids. Their reductive amination gives a simple way of making 1-aminoalkylphosphonic acids. Acetylphosphonic acid inhibited NAD+ reduction by pyruvate with the pyruvate dehydrogenases from Escherichia coli and Bacillus stearothermophilus. The inhibition was competitive with pyruvate, with Ki of 6 microM for the E. coli enzyme (pyruvate Km 0.5 mM) and one of 0.4 mM of the B. stearothermophilus enzyme (pyruvate Km 0.1 mM). Acetylphosphonate and its monomethyl ester are substates for pig heart lactate dehydrogenase, with Km values of 15 mM and 10 mM respectively (pyruvate Km 0.05 mM) and specificity constants one thousandth that for pyruvate.

3-Phosphonoalanine has been made by the Strecker synthesis from phosphonoacetaldehyde, which is easily prepared from vinyl acetate. It gives phosphonopyruvate by transamination when treated with glyoxylate. Phosphonolactate, an analogue of phosphoglycerate, is prepared by reducing phosphonopyruvate. Diazotization of phosphonoalanine was investigated as a route for making phosphonolactate: addition of NaNO2 to the isoelectric form of phosphonoalanine gave much scission of the C-P bond with release of phosphate; addition of HBr prevented this release and gave largely the bromo acid. The supplement reports the synthesis of arsonolactate, a similar analogue, by treating chlorolactate with alkaline arsenite.

A mentally retarded boy with multiple malformations was found to have trisomy for the distal two-thirds of the short arm of chromosome 20 (trisomy 20p), resulting from a paternal translocation (5;20)(p15;p11). The patient had a cleft palate, a feature not present in other trisomy 20p patients. A review of the reported trisomy 20p patients indicates that their varied features do no constitute a readily recognizable clinical syndrome.

Linkage analysis of 146 informative families for MN and Ss resulted in an estimate of the recombination frequency greater than previously reported. Our total is 7 recombinant children out of 467 individuals, including 1 confirmed recombinant (retested and HLA-compatible) and 6 not verified. The 95% confidence interval of our estimate of recombination is 0.0033-0.0167. Our results are compared with two earlier studies.

Adenosine was converted into the arsonomethyl analogue of AMP. The reactions used provide a general route for converting an alcohol, R-CH2-OH, into the arsonomethyl analogue, R-CH2-CH2-AsO3H2, of its phosphate, R-CH2-O-PO3H2. The analogue of AMP proves to be a substrate for rabbit adenylate kinase, which shows a limiting velocity with it of 1/17 that with AMP, a Michaelis constant raised 70-fold to about 10 mM, and hence a specificity constant lowered about 1200-fold. The product of transfer of a phospho group from ATP to the analogue is, like all anhydrides of arsonic acids, unstable to hydrolysis, and so breaks down to yield orthophosphate and regenerate the analogue. Hence adenylate kinase is converted into an ATPase by the presence of the analogue.

One hundred and three unrelated patients with Type 1 (insulin-dependent) diabetes were typed for HLA, properdin factor B (BF), glyoxalase 1 (GLO), Kidd blood group, and 24 other genetic markers. Observed distributions of marker phenotypes among these patients were compared with those expected according to population frequencies, in an attempt to detect associations between Type 1 diabetes and the markers. Strong associations between Type 1 diabetes and both HLA and properdin factor B were confirmed, as was a lack of association between Type 1 diabetes and glyoxalase (GLO). There was an apparent deviation from Hardy-Weinberg equilibrium at the GLO locus, and statistically significant distortions in the distributions of pancreatic amylase (AMY2), galactose-1-phosphate uridyl transferase (GALT), and group-specific component (GC) among Type 1 diabetes patients, but these results are not significant when corrected for performance of multiple tests. An increase in the Lewis-negative phenotype reported elsewhere was observed here but was not statistically significant. A distortion in the distribution of Kidd types reported elsewhere was not confirmed.

Retinoblastoma occurs with increased frequency in children born with a deletion of the long arm of chromosome 13. Recent reviews have noted that the region 13q14 is consistently deleted in documented cases. Prometaphase and late prophase banding allowed Yunis and Ramsay to determine that a deletion in one patient included the sub-bands q14 . 12, q14 . 13, and q14 . 2, and a portion of q14 . 11 and q14 . 3. We report the results of similar cytogenetic techniques applied in the case of a 26 month old Caucasian female with unilateral retinoblastoma, moderate developmental delay, and subtle dysmorphology. Prometaphase banding of cultured skin fibroblasts revealed the karyotype: mos46,XX/46,XX,del(13)(q13 . 1q14 . 11). Only the sub-band q14 . 11 is deleted in both our patient and that of Yunis and Ramsay. The results are consistent with the localisation of the retinoblastoma susceptibility gene(s) in the sub-band 13q14 . 11. Electrophoretic analysis and activity assays of red blood cell esterase D are consistent with hemizygous expression of that marker in our proband. Comparison with published esterase D analyses in families with retinoblastoma permits the assignment of the esterase D locus to that same sub-band, 13q14 . 11.

Extended studies of recently described twins with ring(14) are presented. A single C band and nucleolar organizer region were observed in the r(14). Gene marker evaluations are compatible with monozygosity of the twins.

Genetic linkage analysis of a pedigree with four different alleles for pseudocholinesterase (CHE1) gives a positive lod score of 0.37 at theta = 0.16 for linkage with transferrin (TF), a finding which supports previous reports of linkage between CHE1 and TF. Evaluation of linkage relations of CHE1 and TF using unreported families from our data bank fails to establish linkage with chromosome 1 loci (6-PGD, Rh, PGM1, AMY2 and FY). These results are consistent with recent studies which suggest that TF is on human chromosome 3.

Three separate somatic cell fusions were made between Chinese hamster lines and human lymphocytes containing (1) a 3/4 translocation, (2) an X/9 translocation, and (3) a 17/9 translocation. Eleven independently derived hybrids showed that only human chromosome 22 was consistently present when human ACONM was expressed and absent when human ACONM was not expressed. These studies assign a gene for human ACONM to chromosome 22, and are consistent with prior gene-mapping results.

Taurine and 2-aminoethylphosphonic acid were synthesized by the method of the main paper [Geoghegan & Dixon (1989) Biochem. J. 260, 295-296], i.e. by treating the corresponding halo compound with 2-aminoethanol and then with periodate.

A genetic linkage study, performed on a large family with autosomal dominant retinitis pigmentosa (RP), demonstrated that the RP gene may be linked to the Rh locus, known to be on the short arm of human chromosome 1. Linkage studies on RP along with other studies, can help to more accurately classify these disease entities. Localizing the RP gene locus has the potential for allowing the early diagnosis of individuals at risk.

Evaluation of a family in which electrophoretic variants of the eznyme galactose-1-phosphate uridyl transferase (GALT) and 9qh variants occur demonstrates close linkage between these two traits: lod score of 3.67 at theta = 0. Taken with information indicating GALT is on the short arm of chromosome 9, these linkage data suggest that this locus is close to the centromere on the short arm of chromosome 9.

27 polymorphic genetic markers were analysed for possible linkage with insulin-dependent diabetes mellitus (IDDM). The data set contained 71 families with at least one affected member each. Under three different genetic models for IDDM, evidence was found for linkage between the disease and two distinct sets of marker loci: three markers on chromosome 6 (HLA, properdin factor B, and glyoxalase-1), and the Kidd blood group locus. The families apparently do not fall into two groups, one exhibiting linkage to the HLA complex and the other to the Kidd locus. Thus, two distinct disease-susceptibility loci may be involved in the inheritance of IDDM.

Lymphocytes from a patient with classic galactosemia (GALT deficiency) were hybridized with a Chinese hamster cell line. Electrophoretic valuation of GALT in 31 independently derived interspecific hybrid clones failed to demonstrate expression of the human GALT gene even when human chromosome 9 was present. Possible mechanisms for this lack of expression are presented.

Gene marker analyses have been carried out in a patient with 10q(q23 leads to qter) duplication. The observed elevation of red cell glutamic oxaloacetic transaminase activity is compatible with earlier somatic cell hybridization studies that mapped the locus to this region. Hexokinase-1 activity in the red cells was normal,which is consistent with its prior assignment to the unaffected part of chromosome 10(10pter leads to q23).

A newly developed electrophoretic technique for human galactose-1-phosphate uridyl transferase confirms the multiple band patterns for the Duarte and Los Angeles variants. This represents the first confirmation for the Los Angeles variant. The observed frequencies of N, D, and LA types are similar to earlier reports for these variants.

Chromosomal and gene marker studies of somatic cells in a family with multiple chromosome translocations show apparent instability of the translocations in transmission from generation to generation. This instability is attributed to meiotic crossing-over between the involved chromosomes. Technical advances in chromosome analysis combined with human gene map information in the study of this unusual family demonstrate for the first time that crossing-over involves exchange of chromatin between nonsister chromatids of homologous chromosomes.

Five pedigrees (including an expanded version of a previously reported pedigree) exhibited typical autosomal dominant retinitis pigmentosa were analysed for linkage of RP to 29 genetic markers. No significant lod scores resulted. The largest lod score is +1.51 and suggests linkage between RP and Rh blood group at an estimated recombination fraction of 20% in males and 40% in females. Further studies are needed to confirm or refute this suggested linkage.

Chromosome replication pattern was reevaluated in an unbalanced X/13 translocation carrier, 46,X,der (X),t(X;13)(q27;q12), using the BudR-acridine orange technique. The translocated chromosome, Xpter leads to q27::13q12 leads to 13qter, was late replicating in all analyzed cells. The autosomal segment showed a replication pattern comparable to the two normal, and presumably genetically active, chromosome 13's, with the exception of band 13q22, which was consistently late replicating. Measurements of red-cell levels of esterase D (ESD) (a marker assigned to 13q14) showed a 50% increase in ESD activity, compared to that in normal controls and parents of the patient. This suggests noninactivation of the ESD locus on the der(X) chromosome, a finding consistent with the late-replication data.

Rabbit antibodies to purified human placental galactose-1-phosphate uridyltransferase (EC 2.7.7.12) were used to establish immunologic cross-reactivity patterns for the enzyme in hemolysates, prepared from red cells of a normal individual, a homozygous Duarte variant, and a heterozygous Los Angeles variant. The antibody immunoprecipitated all three forms of the enzyme. The amount of antibody absorbed by each hemolysate was related to the different levels of activity, and examination of hemolysate/antibody reaction mixtures by starch gel electrophoresis revealed that the antibody quantitatively precipitated all of the isoenzyme forms that characterize these three genetic variants.

4-Arsono-2-hydroxybutanoic acid, the analogue of 3-phosphoglycerate in which -CH2-AsO3H2 replaces -O-PO3H2, was synthesized. It proved to be a substrate for phosphoglycerate kinase. Its Michaelis constant was only slightly higher than that of the natural substrate, but its catalytic constant was about 1300 times smaller.

Seventeen independently derived primary mouse-human hybrid clones were scored for the expression of human phosphoglycolate phosphatase (PGP) by electrophoresis and for the presence of human chromosomes with the aid of Q banding. The correlation of biochemical and cytogenetic analyses shows that the segregation of human PGP in these hybrids is concordant only with human chromosome 16, thus enabling the assignment of the genetic locus for PGP to human chromosome 16.

Haemopoietic cells with pluripotent capabilities, were grown in soft-gel cultures from the peripheral blood of a glucose-6-phosphate dehydrogenase (G6PD) electrophoretic A,B heterozygous female with chronic myelocytic and granulocytic progeny. Only type B isoenzyme of G6PD was found in mixed colonies, in mature neutrophils, erythrocytes, and committed granulocyte and isoenzymes of G6PD. This study provides direct evidence that a pluripotent haemopoietic stem cell is involved in the malignant clone in CML.