The gephyrin scaffold modulates cortical layer 2/3 pyramidal neuron responsiveness to single whisker stimulation

Gephyrin is the main scaffolding protein at inhibitory postsynaptic sites, and its clusters are the signaling hubs where several molecular pathways converge. Post-translational modifications (PTMs) of gephyrin alter GABAA receptor clustering at the synapse, but it is unclear how this affects neuronal activity at the circuit level. We assessed the contribution of gephyrin PTMs to microcircuit activity in the mouse barrel cortex by slice electrophysiology and in vivo two-photon calcium imaging of layer 2/3 (L2/3) pyramidal cells during single-whisker stimulation. Our results suggest that, depending on the type of gephyrin PTM, the neuronal activities of L2/3 pyramidal neurons can be differentially modulated, leading to changes in the size of the neuronal population responding to the single-whisker stimulation. Furthermore, we show that gephyrin PTMs have their preference for selecting synaptic GABAA receptor subunits. Our results identify an important role of gephyrin and GABAergic postsynaptic sites for cortical microcircuit function during sensory stimulation.

Brain organoid-on-a-chip to create multiple domains in forebrain organoids

Brain organoids are three-dimensionally reconstructed brain tissue derived from pluripotent stem cells in vitro. 3D tissue cultures have opened new avenues for exploring development and disease modeling. However, some physiological conditions, including signaling gradients in 3D cultures, have not yet been easily achieved. Here, we introduce Brain Organoid-on-a-Chip platforms that generate signaling gradients that in turn enable the induction of topographic forebrain organoids. This creates a more continuous spectrum of brain regions and provides a more complete mimic of the human brain for evaluating neurodevelopment and disease in unprecedented detail.

Adamtsl3 mediates DCC signaling to selectively promote GABAergic synapse function

The molecular code that controls synapse formation and maintenance in vivo has remained quite sparse. Here, we identify that the secreted protein Adamtsl3 functions as critical hippocampal synapse organizer acting through the transmembrane receptor DCC (deleted in colorectal cancer). Traditionally, DCC function has been associated with glutamatergic synaptogenesis and plasticity in response to Netrin-1 signaling. We demonstrate that early post-natal deletion of Adamtsl3 in neurons impairs DCC protein expression, causing reduced density of both glutamatergic and GABAergic synapses. Adult deletion of Adamtsl3 in either GABAergic or glutamatergic neurons does not interfere with DCC-Netrin-1 function at glutamatergic synapses but controls DCC signaling at GABAergic synapses. The Adamtsl3-DCC signaling unit is further essential for activity-dependent adaptations at GABAergic synapses, involving DCC phosphorylation and Src kinase activation. These findings might be particularly relevant for schizophrenia because genetic variants in Adamtsl3 and DCC have been independently linked with schizophrenia in patients.

Suprachiasmatic to paraventricular nuclei interaction generates normal food searching rhythms in mice

Searching for food follows a well-organized decision process in mammals to take up food only if necessary. Moreover, scavenging is preferred during their activity phase. Various time-dependent regulatory processes have been identified originating from the suprachiasmatic nuclei (SCN), which convert external light information into synchronizing output signals. However, a direct impact of the SCN on the timing of normal food searching has not yet been found. Here, we revisited the function of the SCN to affect when mice look for food. We found that this process was independent of light but modified by the palatability of the food source. Surprisingly, reducing the output from the SCN, in particular from the vasopressin releasing neurons, reduced the amount of scavenging during the early activity phase. The SCN appeared to transmit a signal to the paraventricular nuclei (PVN) via GABA receptor A1. Finally, the interaction of SCN and PVN was verified by retrograde transport-mediated complementation. None of the genetic manipulations affected the uptake of more palatable food. The data indicate that the PVN are sufficient to produce blunted food searching rhythms and are responsive to hedonistic feeding. Nevertheless, the search for normal food during the early activity phase is significantly enhanced by the SCN.

A genetically encoded sensor for in vivo imaging of orexin neuropeptides

Orexins (also called hypocretins) are hypothalamic neuropeptides that carry out essential functions in the central nervous system; however, little is known about their release and range of action in vivo owing to the limited resolution of current detection technologies. Here we developed a genetically encoded orexin sensor (OxLight1) based on the engineering of circularly permutated green fluorescent protein into the human type-2 orexin receptor. In mice OxLight1 detects optogenetically evoked release of endogenous orexins in vivo with high sensitivity. Photometry recordings of OxLight1 in mice show rapid orexin release associated with spontaneous running behavior, acute stress and sleep-to-wake transitions in different brain areas. Moreover, two-photon imaging of OxLight1 reveals orexin release in layer 2/3 of the mouse somatosensory cortex during emergence from anesthesia. Thus, OxLight1 enables sensitive and direct optical detection of orexin neuropeptides with high spatiotemporal resolution in living animals.

Quantitative examination of early diabetes by light-emitting diodes light-induced pupillary light reflex

This study investigated the abnormal pupillary light reflex in patients with early diabetes mellitus (DM) without retinopathy by using a custom-made noninvasive portable pupilometer. The pupilometer recorded and analyzed the pupillary light reflex. Two light intensities, 0.2 cd and 1.2 cd, and four wavelengths of stimulus light-white (400 nm-800 nm), red (640 ± 5 nm), green (534 ± 5 nm), and blue (470 ± 5 nm)-were used to stimulate the pupil for 10 ms. The pupillary response was recorded for 15 s. A total of 40 healthy people and 40 people with DM without retinopathy participated in the experiment at the National Taiwan University Hospital. The mean and standard deviation of DM duration were 4.5 years and 3.9 years. Of the 16 indices, the duration that pupil restores from its minimum size to half of its resting size (DRP), maximum pupil restoration velocity (MRV), and average restoration velocity (ARV) exhibited the most significant differences between the healthy people and those with DM. Compared with healthy participants, DRP was 16.33% higher, and MRV and ARV were 17.45% and 4.58% lower, respectively, in those with DM. This might be attributable to the sympathetic nervous system (SNS) controlling the dilator muscle during the dark-adapted period and relaxing the pupil; the SNS had few degenerated nerve endings in people with DM. The three aforementioned indices might be used to evaluate the severity of autonomic neuropathy in early DM.

Lactobacillus paracasei PS23 reduced early-life stress abnormalities in maternal separation mouse model

Maternal separation (MS) has been developed as a model for inducing stress and depression in studies using rodents. The concept of the gut-brain axis suggests that gut health is essential for brain health. Here, we present the effects of administration of a probiotic, Lactobacillus paracasei PS23 (PS23), to MS mice against psychological traits including anxiety and depression. The administration of live and heat-killed PS23 cells showed positive behavioural effects on MS animals, where exploratory tendencies and mobility were increased in behavioural tests, indicating reduced anxiety and depression compared to the negative control mice (P<0.05). Mice administered with both live and heat-killed PS23 cells also showed lower serum corticosterone levels accompanied by higher serum anti-inflammatory interleukin 10 (IL-10) levels, compared to MS separated mice (P<0.05), indicating a stress-elicited response affiliated with increased immunomodulatory properties. Assessment of neurotransmitters in the brain hippocampal region revealed that PS23 affected the concentrations of dopaminergic metabolites differently than the control, suggesting that PS23 may have improved MS-induced stress levels via neurotransmitter pathways, such as dopamine or other mechanisms not addressed in the current study. Our study illustrates the potential of a probiotic in reversing abnormalities induced by early life stress and could be an alternative for brain health along the gut-brain axis.

RhoGEF9 splice isoforms influence neuronal maturation and synapse formation downstream of α2 GABAA receptors

In developing brain neuronal migration, dendrite outgrowth and dendritic spine outgrowth are controlled by Cdc42, a small GTPase of the Rho family, and its activators. Cdc42 function in promoting actin polymerization is crucial for glutamatergic synapse regulation. Here, we focus on GABAergic synapse-specific activator of Cdc42, collybistin (CB) and examine functional differences between its splice isoforms CB1 and CB2. We report that CB1 and CB2 differentially regulate GABAergic synapse formation in vitro along proximal-distal axis and adult-born neuron maturation in vivo. The functional specialization between CB1 and CB2 isoforms arises from their differential protein half-life, in turn regulated by ubiquitin conjugation of the unique CB1 C-terminus. We report that CB1 and CB2 negatively regulate Cdc42; however, Cdc42 activation is dependent on CB interaction with gephyrin. During hippocampal adult neurogenesis CB1 regulates neuronal migration, while CB2 is essential for dendrite outgrowth. Finally, using mice lacking Gabra2 subunit, we show that CB1 function is downstream of GABA_ARs, and we can rescue adult neurogenesis deficit observed in Gabra2 KO. Overall, our results uncover previously unexpected role for CB isoforms downstream of α2-containing GABA_ARs during neuron maturation in a Cdc42 dependent mechanism.

GABAergic inhibition regulates distinct stages of brain development; however, cellular mechanisms downstream of GABA_A receptors (GABA_ARs) that influence neuronal migration, maturation and synaptogenesis are less clear. ArfGEF9 encodes for RhoGEF with Cdc42 and TC10 GTPase as its substrates. Interestingly, ArhGEF9 is the only known RhoGEF essential for GABAergic synapse formation and maintenance. We report that during brain development ArfGEF9 mRNA splicing regulation generates different ratios of CB1 and CB2 splice isoforms. CB1 mRNA splicing is enhanced during early brain developmental, while CB2 levels remains constant throughout brain development. We also show that CB1 protein has shorter half-life and ubiquitin proteasome system restricts CB1 abundance within developing neuron to modulate neuron migration and distributing GABAergic synapse along the proximal-distal axis. On the other hand, CB2 isoform although expressed abundantly throughout brain development is essential for neuron dendrite maturation. Together, our data identifies specific post-transcriptional and post-translational mechanisms downstream of GABA_ARs influencing ArhGEF9 function to regulate distinct aspects of neuronal maturation process.

Evaluation of the potential anti-allergic effects of heat-inactivated Lactobacillus paracasei V0151 in vitro, ex vivo, and in vivo

The efficacy of Lactobacillus paracasei V0151 (V0151), isolated from the faeces of a child, to modulate immune responses was investigated. In RAW 264.7 cells expressing an inducible nitric oxide synthase (iNOS)-directed luciferase gene, heat-inactivated V0151 stimulated iNOS expression followed by nitric oxide production. V0151 significantly elevated interferon gamma, interleukin (IL)-10, tumour necrosis factor alpha, and IL-1β production in human peripheral blood mononuclear cells. In splenocytes isolated from ovalbumin (OVA)-sensitised BALB/c mice treated with OVA and V0151 at different bacterium-to-cell ratios (1:1, 10:1, and 20:1) for 96 h, IL-2, IL-4, IL-5, and IL-13 production was dose-dependently downregulated, whereas IL-12 was dose-dependently upregulated. Collectively, our findings indicate that V0151 might regulate pro-inflammatory factors in macrophages and splenocytes. Furthermore, the T helper 1/T helper 2 (Th1/Th2) balance was also skewed toward Th1 dominance through the elevation of Th1 cytokine production.

The behavioural response of mice lacking NK₁ receptors to guanfacine resembles its clinical profile in treatment of ADHD

Background and Purpose

Mice with functional ablation of substance P-preferring neurokinin-1 receptors (NK1R−/− mice) display behavioural abnormalities resembling those in attention deficit hyperactivity disorder (ADHD). Here, we investigated whether the ADHD treatment, guanfacine, alleviated the hyperactivity and impulsivity/inattention displayed by NK1R−/− mice in the light/dark exploration box (LDEB) and 5-choice serial reaction–time task (5-CSRTT), respectively. Following reports of co-morbid anxiety in ADHD, we also investigated effects of guanfacine on anxiety-like behaviour displayed by NK1R−/− and wild-type (WT) mice in the elevated plus maze (EPM).

Experimental Approach

Mice were treated with guanfacine (0.1, 0.3 or 1.0 mg·kg⁻¹, i.p.), vehicle or no injection and tested in the 5-CSRTT or the LDEB. Only the lowest dose of guanfacine was used in the EPM assays.

Key Results

In the 5-CSRTT, a low dose of guanfacine (0.1 mg·kg⁻¹) increased attention in NK1R−/− mice, but not in WT mice. This dose did not affect the total number of trials completed, latencies to respond or locomotor activity in the LDEB. Impulsivity was decreased by the high dose (1.0 mg·kg⁻¹) of guanfacine, but this was evident in both genotypes and is likely to be secondary to a generalized blunting of behaviour. Although the NK1R−/− mice displayed marked anxiety-like behaviour, guanfacine did not affect the behaviour of either genotype in the EPM.

Conclusions and Implications

This evidence that guanfacine improves attention at a dose that did not affect arousal or emotionality supports our proposal that NK1R−/− mice express an attention deficit resembling that of ADHD patients.

Linked Articles

This article is part of a themed section on Animal Models in Psychiatry Research. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-20

A lack of functional NK1 receptors explains most, but not all, abnormal behaviours of NK1R-/- mice(1)

Mice lacking functional neurokinin-1 receptors (NK1R-/-) display abnormal behaviours seen in Attention Deficit Hyperactivity Disorder (hyperactivity, impulsivity and inattentiveness). These abnormalities were evident when comparing the behaviour of separate (inbred: 'Hom') wildtype and NK1R-/- mouse strains. Here, we investigated whether the inbreeding protocol could influence their phenotype by comparing the behaviour of these mice with that of wildtype (NK1R+/+) and NK1R-/- progeny of heterozygous parents ('Het', derived from the same inbred strains). First, we recorded the spontaneous motor activity of the two colonies/genotypes, over 7 days. This continuous monitoring also enabled us to investigate whether the diurnal rhythm in motor activity differs in the two colonies/genotypes. NK1R-/- mice from both colonies were hyperactive compared with their wildtypes and their diurnal rhythm was also disrupted. Next, we evaluated the performance of the four groups of mice in the 5-Choice Serial Reaction-Time Task (5-CSRTT). During training, NK1R-/- mice from both colonies expressed more impulsive and perseverative behaviour than their wildtypes. During testing, only NK1R-/- mice from the Hom colony were more impulsive than their wildtypes, but NK1R-/- mice from both colonies were more perseverative. There were no colony differences in inattentiveness. Moreover, a genotype difference in this measure depended on time of day. We conclude that the hyperactivity, perseveration and, possibly, inattentiveness of NK1R-/- mice is a direct consequence of a lack of functional NK1R. However, the greater impulsivity of NK1R-/- mice depended on an interaction between a functional deficit of NK1R and other (possibly environmental and/or epigenetic) factors.

Characterization ofD-Aminoacylase fromAlcaligenes denitrificansDA181

The D-aminoacylase produced by Alcaligenes denitrificans DA181 was a new type of aminoacylase which had both high stereospecificity and specific activity. The molecular weight and isoelectric point of this enzyme were 58,000 and 4.4, respectively. The apparent Km and kcat values of this enzyme for N-acetyl-D-methionine were estimated to be 0.48 mM and 6.24 x 10(4) min-1, respectively. The optimum temperature was 45 degrees C. The enzyme was stable up to 55 degrees C for 1 hr in the presence of 0.2 mg/ml bovine serum albumin. The enzyme was stable in the pH range of 6.0 to 11.0 with an optimum pH of 7.5. This enzyme contained about 2.1 g atom of zinc per mole of enzyme. Enzyme activity was inhibited by incubation with EDTA. The inhibition by EDTA was fully reversed by Co2+ and partially by Zn2+.

First Report of Didymella bryoniae Causing Gummy Stem Blight of Chayote in Taiwan

Chayote (Sechium edule (Jacq.) Swartz, Cucurbitaceae), originally native to Mexico, is an important vegetable known as "dragon-whisker vegetable" and is cultivated for its shoots in Ji-an, Hualien County in eastern Taiwan. In June 2010, 70 to 80% of the chayote plants grown in Ji-an developed necrotic spots on stems, leaves, and fruits. The disease was severe during the warm and rainy season from June to August. The symptoms on stems, leaves, and fruits were water-soaked lesions that eventually dried up, cracked, and produced perithecia on necrotic tissues. A single ascospore was isolated from perithecia harvested from diseased stems and cultured on potato dextrose agar (PDA) at 25°C for 1 month. Colonies of three isolates (SE5, SE6, and SE7) were white to olivaceous green bearing unicellular conidia measuring 2 to 5 × 3 to 10 μm, which is consistent with the morphological characteristics of Didymella bryoniae (Auersw.) Rehm (anamorph Phoma cucurbitacearum (Fr.:Fr.) Sacc.) (1,2,3). DNA of SE5, SE6, and SE7 isolates were obtained using microwave-based method (4). The internal transcribed spacer (ITS) rDNA (GenBank accessions AB714984, AB714985, and AB714986), PCR-amplified using primers ITS1 and ITS4, had 98 to 99% nucleotide sequence identity with D. bryoniae (GenBank Accession Nos. GU045304 and GU592001). A pathogenicity test was conducted in a greenhouse with temperature ranging from 20 to 30°C. Three-day-old mycelial plugs (5 × 5 mm) of the three isolates were placed on the needle-pricked wounds of stems and leaves of 36 4-month-old potted chayote plants wrapped in plastic bags to maintain 100% relative humidity for 2 days. Six days after inoculation, water-soaked lesions formed on the stems and leaves. Controls inoculated with sterile water had no symptoms. The fungus reisolated from the lesions of diseased stems and leaves had morphological characteristics of D. bryoniae. Based on the results of morphology, molecular data, and pathogenicity tests, we reported for the first time to our knowledge that gummy stem blight of chayote is caused by D. bryoniae in Taiwan. References: (1) J. W. Huang and W. R. Hsieh. Plant Prot. Bull. 27:325, 1985. (2) A. P. Keinath et al. Phytopathology 85:364, 1995. (3) E. Punithalingam and P. Holliday. P. 332 in: Descriptions of Pathogenic Fungi and Bacteria. CMI, Kew, Surrey, UK, 1972. (4) S. R. Tendulkar et al. Biotechnol. Lett. 22:1941, 2003.

Parallel optical trap assisted nanopatterning on rough surfaces

There exist many optical lithography techniques for generating nanostructures on hard, flat surfaces over large areas. However, few techniques are able to create such patterns on soft materials or surfaces with pre-existing structure. To address this need, we demonstrate the use of parallel optical trap assisted nanopatterning (OTAN) to provide an efficient and robust direct-write method of producing nanoscale features without the need for focal plane adjustment. Parallel patterning on model surfaces of polyimide with vertical steps greater than 1.5 µm shows a feature size uncertainty better than 4% across the step and lateral positional accuracy of 25 nm. A Brownian motion model is used to describe the positional accuracy enabling one to predict how variation in system parameters will affect the nanopatterning results. These combined results suggest that OTAN is a viable technique for massively parallel direct-write nanolithography on non-traditional surfaces.

Preparative chromatography of flavonoids and saponins in Gynostemma pentaphyllum and their antiproliferation effect on hepatoma cell

A preparative column chromatographic method was developed to isolate flavonoids and saponins from Gynostemma pentaphyllum, a Chinese Medicinal herb, and evaluate their antiproliferation effect on hepatoma cell Hep3B, with the standards rutin and ginsenoside Rb(3) being used for comparison. Initially the powdered G. pentaphyllum was extracted with ethanol, followed by eluting flavonoids and saponins with ethanol-water (30:70, v/v) and 100% ethanol, respectively, in an open-column containing 5 g of Cosmosil 75C(18)-OPN, and then subjected to HPLC-MS analysis. The flavonoid fraction was mainly composed of quercetin- and kaempferol-glycosides, while in saponin fraction, both ginsenoside Rb(3) and ginsenoside Rd dominated. Both fractions were more effective against Hep3B cells than the standards rutin and ginsenoside Rb(3), with the cell cycle being arrested at G0/G1 phase for all the treatments. Additionally, the inhibition effect followed a dose-dependent increase for all the sample treatments. The result of this study may be used as a basis for possible phytopreparations in the future with G. pentaphyllum as raw material.

Lack of association of mannose-binding lectin gene polymorphisms with development and clinical manifestations of systemic lupus erythematosus in Chinese children

Mannose-binding lectin (MBL) gene polymorphisms may be associated with adult-onset systemic lupus erythematosus (SLE), but studies in children with SLE are rare. This study tested the genetic association between MBL polymorphisms and paediatric-onset SLE in a cohort of Chinese children in Taiwan. In all 150 children with SLE and 100 healthy controls of comparable age were genotyped for codon 52, 54 and 57 mutations of the MBL gene using a polymerase chain reaction–based assay. Clinical manifestations, organ involvement, disease activity, laboratory characteristics and outcome were recorded and compared between patients with different MBL genotypes. Codon 54 mutation was fairly common in both SLE patients and controls, whereas codon 52 and codon 57 mutations were not detected in our study subjects. No statistically significant differences were found in allele frequencies of the codon 54 mutation between SLE and control groups. Moreover, no association was found between this MBL polymorphism and clinical manifestations, organ involvement, disease activity, laboratory characteristics or outcome of SLE. These results suggest that MBL polymorphisms do not influence susceptibility to paediatric-onset SLE and do not influence clinical manifestations of SLE in Chinese children.

RING-dependent tumor suppression and G2/M arrest induced by the TRC8 hereditary kidney cancer gene

TRC8/RNF139 and von Hippel-Lindau (VHL) both encode E3 ubiquitin (Ub) ligases mutated in clear-cell renal carcinomas (ccRCC). VHL, inactivated in nearly 70% of ccRCCs, is a tumor suppressor encoding the targeting subunit for a Ub ligase complex that downregulates hypoxia-inducible factor-alpha. TRC8/RNF139 is a putative tumor suppressor containing a sterol-sensing domain and a RING-H2 motif essential for Ub ligase activity. Here we report that human kidney cells are growth inhibited by TRC8. Inhibition is manifested by G2/M arrest, decreased DNA synthesis and increased apoptosis and is dependent upon the Ub ligase activity of the RING domain. Tumor formation in a nude mouse model is inhibited by TRC8 in a RING-dependent manner. Expression of TRC8 represses genes involved in cholesterol and fatty acid biosynthesis that are transcriptionally regulated by the sterol response element binding proteins (SREBPs). Expression of activated SREBP-1a partially restores the growth of TRC8-inhibited cells. These data suggest that TRC8 modulation of SREBP activity comprises a novel regulatory link between growth control and the cholesterol/lipid homeostasis pathway.

Infusion of human umbilical cord blood cells protect against cerebral ischemia and damage during heatstroke in the rat

Intravenously delivered human umbilical cord blood cells (HUCBC) have been previously shown to improve both morphologic and functional recovery of heat-stroked rats. To extend these findings, we examined both the morphologic and functional alterations in the presence of HUCBC or human peripheral mononuclear cells (PBMC) 24 h before initiation of heatstroke. Anesthetized rats, 1 day before the initiation of heatstroke, were divided into three major groups and given the following: (a) serum-free lymphocyte medium (0.3 ml) intravenously; (b) PBMC (5 x 10(6) in 0.3 ml serum-free lymphocyte medium); or (c) HUCBC (5 x 10(6) in 0.3 ml serum-free lymphocyte medium). Another group of rats were exposed to room temperature (26 degrees C) and used as normothermic controls. In vehicle-treated heatstroke rats, their mean arterial pressure, cerebral blood flow, and brain PO(2) were all lower than in normothermic controls after the onset of heatstroke. However, their body temperatures and striatal levels of inducible nitric oxide synthase (iNOS)-dependent NO, ischemia and damage markers (e.g., glycerol, glutamate, and lactate/pyruvate ratio), and neuronal damage in the striatum were all greater. The heatstroke-induced arterial hypotension, cerebral ischemia and hypoxia, and increased levels of iNOS-dependent NO in the striatum were all significantly reduced by pretreatment with HUCBC, but not with PBMC. Moreover, HUCBC were localized by immunohistochemistry and PCR analysis in the injured brain structures and spleen. These findings indicate that HUCBC transplantation, in addition to having therapeutic values, can be a good choice for preventing heatstroke occurrence.

Comparative evaluation of the BACTEC MGIT 960 system with solid medium for isolation of mycobacteria

SETTING

The utilisation of new, rapid methods of diagnosis of tuberculosis is currently of great interest for tuberculosis control. This study was carried out in a teaching hospital in the eastern region of Taiwan.

OBJECTIVE

The BACTEC MGIT 960 system was evaluated and compared with Lowenstein-Jensen (LJ) medium and Middlebrook 7H11 plate for recovery rate and time to detection of mycobacteria.

DESIGN

A total of 1396 sputum samples were tested for the presence of mycobacteria. Specimens were processed and inoculated separately in the BACTEC MGIT 960 system, on LJ medium and 7H11 for comparative study.

RESULTS

The BACTEC MGIT 960 detected 235 isolates (100%), followed by LJ with 205 isolates (87.2%) and 7H11 with 178 isolates (75.7%). The mean time to detection of Mycobacterium tuberculosis complex was 11.6 days with MGIT 960, 20.1 days with LJ, and 18.7 days with 7H11. The contamination rates were 15.1% with MGIT 960, 10.1% with LJ and 9.7% with 7H11.

CONCLUSION

The BACTEC MGIT 960 system is a sensitive, rapid mycobacterial culturing system. However, the high contamination rate is a concern that should be carefully evaluated in the clinical setting.

Sialyltransferase family members and cervix squamous cell carcinoma

Sialic acids including a number of their derivatives are ubiquitous at the terminal positions of the oligosaccharides of glycoproteins. The transfer of sialic acids from cystidine-5-monophospho-N-acetylneuraminic acid (CMP-NeuAc) to the terminal position of the carbohydrate group of glycoproteins and glycolipids is catalyzed by a family of sialyltransferases (STs). There is a large body of evidence to suggest that tumor cells have altered surface properties from their normal counterparts, and that these changes are partially due to altered sialo-glycoconjugates expressed on the plasma membrane and that altered sialylation (change in glycoprotein expression), which occurs during certain pathological processes, such as oncogenic transformation, tumor metastases, and invasion, is associated with enhanced ST activity. In this report we attempt to review the important findings in studing sialyltransferases of cervix squamous cell carcinoma.

Recycling and reuse of wastewater from a new-developed community using sand filtration, ultrafiltration, and ozonation

In this study, the pilot apparatus combined with sand filtration, ozonation and ultrafiltration was established. Wastewater from the secondary treatment effluent in the new-developed community was taken as the sample for looking into the feasibility of domestic wastewater reuse and recycling. The test results by sand filtration, sand filtration/ultrafiltration, sand filtration/ozonation, and sand filtration/ultrafiltration/ozonation were compared for looking for appropriate treatment processes applied in the domestic wastewater reuse and recycling. Finally, cost analysis was carried out and sand filtration/ozonation process was suggested to be one of the best processes. The total cost is about 0.1-0.32 USD dollars per cubic meter of produced water by considering the capital and operation cost for five years in the small domestic wastewater treatment plant (50-750 CMD).

Identification of viridans streptococcal species causing bacterial meningitis in adults in Taiwan

In order to determine the species responsible for viridans-group streptococcal meningitis in adults in Taiwan, seven cases of culture-proven meningitis due to these organisms were studied. The cases were all identified at the Chang Gung Memorial Hospital-Kaohsiung over a period of 3 years, and they accounted for 9% (7/78) of all cases of culture-proven bacterial meningitis occurring in adults during this period. Of the seven viridans streptococci isolates recovered, Streptococcus constellatus accounted for four, Streptococcus anginosus for two, and Streptococcus oralis for one. Thus, it appears that streptococci of the milleri group are the most common species causing bacterial meningitis in adults in Taiwan. The tendency for these organisms to cause invasive central nervous system infections in adults should not be overlooked when these species are recovered from cerebrospinal fluid specimens.

Clinical value of early cleavage embryo

OBJECTIVE

This study was undertaken to see if embryo transfer containing early cleavage embryos resulted in better clinical pregnancy rate.

METHODS

The treatment outcomes of IVF-ET were retrospectively reviewed. Out of 258 transfer cycles, 160 cycles contained no early cleavage embryos (Group I) and 98 cycles contained at least one early cleavage embryo (Group II). The definition of early cleavage embryo is the presence of two blastomeres 24-26 h after insemination. The implantation rate, clinical pregnancy rate were compared between two groups. Student's t-test and the Mann-Whitney U-test were used for continuous variables, and the Chi-squared (chi(2)) test was used for binary variables. Differences were considered statistically significant at P<0.05.

RESULT

The implantation rate and clinical pregnancy rate were 11.6% and 25.6% in Group I, 18.6% and 38.8% in Group II (P<0.05).

CONCLUSION

Early cleavage embryos possess greater implantation potential. Embryo transfer containing early cleavage embryos had a better clinical pregnancy rate.

Ozonation of domestic secondary effluent for recycling and reuse--a pilot plant study

In this study, a pilot plant combined ozonation with sand filtration is established. Wastewater from the secondary effluent was taken as the sample for looking into the feasibility of domestic wastewater recovery and recycling. At the beginning, a series of hydraulic analysis and ozone transfer tests was conducted in the bubble column reactor. From these tests, it was found that when the gas flow is controlled to within 0.2 to approximately 1.0 L/min and liquid flow within 0.5 to approximately 2.5 L/min, using series connected mixing tank model for our calculation, the result J (CSTR) is 1 to approximately 2. From the ozone transfer test it is known that the smaller the gas flow, the better the transfer rate, and the same pattern occurs on ozone gas concentration. After sand filtration and ozone treatment, the G/L ratio within the ozone column reactor can be maintained within 0.2 to approximately 0.4 and the ozone dosage within 8 to approximately 12 mg/L. The removal rate for coliform bacillus, BOD, turbidity and color is 99.96%, 62.2%, 89.6% and 67% respectively. After ozonation treatment, coliform bacillus content can be controlled under 10 CFU/mL, BOD under 10 mg/L, turbidity within 2.0 to approximately 2.5 (NTU), and color within 10.3 to approximately 13.7 degree. The recycled water is almost colorless and odorless, and is capable of reaching the reference standard for recycled water.

Bioanalytical utility of sonovoltammetry

Dopamine dissolved within egg homogenate was used as a model system to study the effects of electrode contamination and its subsequent reactivation through ultrasonically mediated in situ cleaning effects. The merits in conducting electroanalytical investigations under the influence of the ultrasonic field were also appraised. Maintaining the ultrasound field during oxidative measurements was found to yield hydrodynamic profiles that were linear over the concentration range 2-20 microM dopamine. The resulting sonolinear sweep voltammograms were compared with conventional rotating disk measurements, with the former found to provide significantly increased limiting currents that were attenuable through the manipulation of the field intensity. The problem of retaining selectivity in the presence of high concentrations of ascorbate was also assessed with the addition of cupric ion prior to commencing the measurements found to efficiently negate an otherwise substantive interference.

Large scale mapping of methylcytosines in CTCF-binding sites in the human H19 promoter and aberrant hypomethylation in human bladder cancer

The methylation status of binding sites of the insulator protein, CTCF, in the H19 promoter has been suggested as being critical to the regulation of imprinting of the H19/IGF2 locus located in chromosome 11p15. In this study, we have analyzed the methylation of all of seven potential CTCF-binding sites in the human H19 promoter since the methylation status of these sites has not been reported. We found that all the binding sites except the sixth were hypermethylated whereas only the sixth binding site showed allele-specific methylation in normal human embryonic ureteral tissue. We also analyzed the methylation status of these sites in human-mouse somatic-cell-hybrid clones containing a single copy of human chromosome 11 and which were treated with 5-aza-2'-deoxycytidine (5-aza-CdR) to yield clones which expressed human IGF2 and H19 mutually exclusively of each other. In most of the clones, a correlation between methylation of the sixth CTCF-binding site and expression of IGF2 was observed. Therefore, we analyzed the methylation status of this site in human bladder cancer and found hypomethylation of the paternal allele in two of six informative cases. These results demonstrate that only the sixth CTCF-binding site acts as a key regulatory domain for switching between H19 or IGF2 expression, whereas the other sites are not subject to allele-specific methylation. Loss of methylation imprinting of H19 is linked to hypomethylation of the paternal allele in human bladder cancer, unlike the situation in Wilms' tumor and colon cancer where the maternal allele becomes hypermethylated.

A comparison of tramadol, amitriptyline, and meperidine for postepidural anesthetic shivering in parturients

Tramadol is effective for treating shivering during epidural anesthesia in parturients. In addition to its low affinity to opioid receptors, tramadol exerts a modulatory effect on central monoaminergic pathways. In this respect, there are parallels between the mechanisms of the action of tramadol and antidepressants such as amitriptyline. Meperidine is often recommended for the treatment of postanesthetic shivering. This prospective, double-blinded, and randomized clinical study was performed to compare the antishivering effects and accompanying side effects among tramadol, meperidine, and amitriptyline for the treatment of postepidural anesthetic shivering. Forty-five parturients who shivered during cesarean delivery under epidural anesthesia and requested antishivering treatment were randomly allocated to one of three groups for IV treatment: Group T (n = 15) received tramadol 0.5 mg/kg, Group M (n = 15) received meperidine 0.5 mg/kg, and Group A (n = 15) received amitriptyline 15 or 20 mg. The response rate (shivering ceased after treatment in 15 min) was 87% and 93% for Groups T and M, respectively, compared with 13% in Group A (P < 0.01). The time that elapsed from treatment to the time shivering ceased was 5.1 +/- 3.6 min (mean +/- SD) for Group T and 4.2 +/- 2.3 min for Group M. There was a significantly more frequent incidence (33%) of somnolence in Group M when compared with Groups T (7%) and A (0%) (P < 0.01). However, no significant differences were shown for pruritus, nausea, vomiting, or Apgar scores of newborns. We concluded that both tramadol and meperidine show a significantly faster response rate in the treatment of postepidural anesthetic shivering when compared with amitriptyline in the dosage used; tramadol had a decreased incidence of somnolence when compared with meperidine.

IMPLICATIONS

This study was performed to compare the antishivering and side effects among tramadol, amitriptyline, and meperidine for the treatment of postepidural anesthetic shivering in parturients. Both tramadol and meperidine show a significantly faster response rate in the treatment of shivering when compared with amitriptyline. Tramadol had a less frequent incidence of somnolence than meperidine.

Altered mRNA expression of sialyltransferase in squamous cell carcinomas of the cervix

OBJECTIVE

Increased sialylation has been reported in various kinds of cancers, but to date, sialylation of cervical carcinoma has never been evaluated. This study of the changes in messenger ribonucleic acid (mRNA) expression of the four sialyltransferases (ST3Gal I, ST3Gal III, ST3Gal IV, and ST6Gal I) in a normal cervix and that with FIGO stage IB1 squamous cell carcinoma was undertaken to assess the extent of sialylation associated with establishment of the carcinoma.

METHODS

Alterations in ST mRNA expression in FIGO IB1 cervical cancer (n = 30) and normal cervixes (n = 30) were examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

ST6Gal I expression was enhanced in squamous cell carcinoma of the cervix (P = 0.026, Mann-Whitney U test), but mRNA expression from the other three STs (ST3Gal I, ST3Gal III, and ST3Gal IV) was significantly down-expressed in squamous cell carcinoma of the cervix compared to the normal cervix (P = 0.003, P < 0.001, and P = 0.001, respectively). High ST6Gal I expression was associated with more invasive properties of cervical cancer, such as deep stromal invasion, lymph or vascular space involvement, and poor differentiation (P = 0.010, P < 0.001, P < 0.001, respectively).

CONCLUSIONS

A combination of enhanced ST6Gal I mRNA expression and decreased mRNA expression from ST3Gal I, ST3Gal III, and ST3Gal IV might be important in cervical cancer. Future studies will investigate whether RT-PCR detection of the expression of these enzymes can be helpful for prognostic purposes.

Staphylococcus aureus meningitis in adults: a clinical comparison of infections caused by methicillin-resistant and methicillin-sensitive strains

BACKGROUND

This study was undertaken to compare the clinical characteristics of adult methicillin-sensitive Staphylococcus aureus (MSSA) meningitis and adult methicillin-resistant S. aureus (MRSA) meningitis.

PATIENTS AND METHODS

The clinical characteristics and therapeutic outcomes of 19 adult patients with S. aureus meningitis, including eight with MSSA infections and 11 with MRSA infections, were analyzed. A comparison was made between the clinical data of the patients with MSSA infections and those with MRSA infections.

RESULTS

Before the end of 1995, MSSA infection was involved in all the adult patients with S. aureus meningitis but thereafter, MRSA infection was involved in 79% of the cases. The clinical characteristics found in patients with MSSA infection included underlying medical disorders (75%), community-acquired infection (75%) and mortality rate (13%). The clinical characteristics found in patients with MRSA infection included post-neurosurgical states (91%), nosocomial infections (100%), men outnumbering women (8:3), hydrocephalus (36%) and mortality rate (56%). Comparative study between the patient groups (hematogenous and post-neurosurgical) showed that only the mode of acquisition of infection had statistical significance.

CONCLUSIONS

This study showed an increase in MRSA infections in adult S. aureus meningitis in recent years. The clinical characteristics of patients with MSSA and MRSA meningitis were different. Community-acquired infection was common in hematogenous S. aureus meningitis, while nosocomial infection was common in post-neurosurgical S. aureus meningitis. Vancomycin should be considered as one of the drugs of choice for initial therapy of adult bacterial meningitis, especially in post-neurosurgical patients.

Cloning and characterization of a blue fluorescent protein from Vibrio vulnificus

The blue fluorescent protein (BFPVV) gene bfpvv from Vibrio vulnificus CKM-1 was cloned and sequenced. The transformants exhibited blue fluorescence when irradiated by UV source. Nucleotide sequence analysis predicted an ORF of 717 bp encoding a 239-amino-acid polypeptide with a calculated molecular mass of 25.8 kDa. The nucleotide sequence of the bfpvv gene and its deduced amino acid sequence showed significant homology to those of the short-chain dehydrogenase/reductase (SDR) family proteins from various organisms. Some functionally important residues in SDR were strictly conserved in BFPVV, such as an active-site Tyr145, a catalytic site Lys149, and a common GlyXXXGlyXGly pattern in the N-terminal part of the molecule. By changing three amino acid residues, Tyr145, Lys149, and Gly9 to Phe, Ile, and Val, respectively, it was found that the G9V mutant did not generate blue fluorescence, while mutants Y145F and K149I have 126 and 68.5% fluorescence compared with the wild-type BFPVV.

Determinations of morin, quercetin and their conjugate metabolites in serum

Morin and quercetin are isomeric antioxidant flavonols. High-performance liquid chromatographic methods were developed for the quantitation of morin and quercetin in serum. The method employed a Cosmosil RP-18 column, using acetonitrile/0.2% o-phosphoric acid 28/72 and 27/73 (v/v) as mobile phases, with ethyl paraben and 6,7-dimethoxycoumarin used as internal standards for morin and quercetin, respectively. Moreover, a strategy to stabilize morin/quercetin released from their glucuronides/sulfates in serum during hydrolysis was established. The present methods are applicable for determining morin, quercetin, and their glucuronides/sulfates in serum.

On the origin of selective nitrous oxide N-N bond cleavage by three-coordinate molybdenum(III) complexes

Reaction of Mo(N[R]Ar)(3) (R = (t)Bu or C(CD(3))(2)CH(3)) with N(2)O gives rise exclusively to a 1:1 mixture of nitride NMo(N[R]Ar)(3) and nitrosyl ONMo(N[R]Ar)(3), rather than the known oxo complex OMo(N[R]Ar)(3) and dinitrogen. Solution calorimetry measurements were used to determine the heat of reaction of Mo(N[R]Ar)(3) with N(2)O and, independently, the heat of reaction of Mo(N[R]Ar)(3) with NO. Derived from the latter measurements is an estimate (155.3 +/- 3.3 kcal.mol(-1)) of the molybdenum-nitrogen bond dissociation enthalpy for the terminal nitrido complex, NMo(N[R]Ar)(3). Comparison of the new calorimetry data with those obtained previously for oxo transfer to Mo(N[R]Ar)(3) shows that the nitrous oxide N-N bond cleavage reaction is under kinetic control. Stopped-flow kinetic measurements revealed the reaction to be first order in both Mo(N[R]Ar)(3) and N(2)O, consistent with a mechanism featuring post-rate-determining dinuclear N-N bond scission, but also consistent with cleavage of the N-N bond at a single metal center in a mechanism requiring the intermediacy of nitric oxide. The new 2-adamantyl-substituted molybdenum complex Mo(N[2-Ad]Ar)(3) was synthesized and found also to split N(2)O, resulting in a 1:1 mixture of nitrosyl and nitride products; the reaction exhibited first-order kinetics and was found to be ca. 6 times slower than that for the tert-butyl-substituted derivative. Discussed in conjunction with studies of the 2-adamantyl derivative Mo(N[2-Ad]Ar)(3) is the role of ligand-imposed steric constraints on small-molecule, e.g. N(2) and N(2)O, activation reactivity. Bradley's chromium complex Cr(N(i)Pr(2))(3) was found to be competitive with Mo(N[R]Ar)(3) for NO binding, while on its own exhibiting no reaction with N(2)O. Competition experiments permitted determination of ratios of second-order rate constants for NO binding by the two molybdenum complexes and the chromium complex. Analysis of the product mixtures resulting from carrying out the N(2)O cleavage reactions with Cr(N(i)Pr(2))(3) present as an in situ NO scavenger rules out as dominant any mechanism involving the intermediacy of NO. Simplest and consistent with all the available data is a post-rate-determining bimetallic N-N scission process. Kinetic funneling of the reaction as indicated is taken to be governed by the properties of nitrous oxide as a ligand, coupled with the azophilic nature of three-coordinate molybdenum(III) complexes.

Soyasaponin I, a potent and specific sialyltransferase inhibitor

A growing number of reports demonstrate that hypersialylation, which is observed in certain pathological processes, such as oncogenic transformation, tumor metastasis, and invasion, is associated with enhanced sialyltransferase (ST) activity. There is therefore a need for the development of ST inhibitors to modulate ST activity and thus alleviate the disease processes caused by STs. In the present study, soyasaponin I had been discovered to be a potent and specific ST inhibitor by screening strategy from 7500 samples including micribial extracts and natural products. Kinetic analysis shows that it is a CMP-Neu5Ac competitive inhibitor with for ST3Gal I with an inhibition constant (K(i)) of 2.1 microM. In addition, it is only active against ST, but not against the other tested glycosyltransferases and glycosidases. Our study is the first report to discover ST inhibitor by screening method and also to provide the new chemical structure information that should be useful in the development of other novel ST inhibitors.

Direct Tramadol Application on Sciatic Nerve Inhibits Spinal Somatosensory Evoked Potentials in Rats

We sought to determine the possible neural conduction blockade of tramadol and whether there is evidence of localized neural toxicity with spinal somatosensory evoked potential (SSEP) measurements. Male Wistar rats were used. SSEP, elicited by supramaximally stimulating the hind paw and recorded from the thoracolumbar and the first and second lumbar interspinous ligaments, was monitored. SSEPs were obtained before drug application as the pretreatment baseline and measured every 15 min after treatment for 2 h and at 60-min intervals thereafter until SSEP returned to baseline or for another 4 h. Two small strips of Gelfoam (0.6 x 1.0 cm(2)) soaked with the drug were placed under and over the left sciatic nerve for a 30-min period. Gelfoam was prepared with tramadol hydrochloride (Tramal; the US trade name is Ultram) 5, 2.5, and 1.25 mg, diluted if needed with saline to a total volume of 100 microL (5%, 2.5%, and 1.25%, respectively). The control data were obtained from the right side limb with normal saline by following the same method. Spinal SSEPs were measured after 48 h to detect the late neural damage. The results showed that direct tramadol application on sciatic nerves dose-dependently reduced both the amplitude and conduction velocity of SSEPs when compared with the pretreatment baseline. All SSEPs returned to pretreatment baseline, and no significant changes of SSEP between bilateral limbs were noted at the 48-h measurements. No evidence of irreversible conduction blockade indicative of local neural toxicity was seen. Pretreatment with naloxone 1 mg/kg failed to block the changes of SSEP produced by 2.5% tramadol 100 microL. We conclude that tramadol exerts a local anesthetic-type effect on peripheral nerves.

Endometrium estimation in a sequence of ultrasonic images

In this paper a novel algorithm for motion estimation of the endometrium in a sequence of ultrasonic images is presented. The algorithm used is based on the criterion that a pixel of a motion object at different times has a different gray value. The motion estimation includes motion frequency and thickness; the former one is determined by the detection of change of a pixel value in a sequence of images during a given time period, and the latter is the result of the object's dimension divided by its extended width. The algorithm has been tested on synthetic and real images, and the results are encouraging.

Effects of tramadol on T lymphocyte proliferation and natural killer cell activity in rats with sciatic constriction injury

We investigated the effects of acute and chronic tramadol treatment on T lymphocyte function and natural killer (NK) cell activity in rats receiving chronic constriction injury (CCI) of the sciatic nerve. T lymphocyte function was evaluated based on concanavalin-A (ConA)- and phytohemagglutinin (PHA)-induced splenocyte proliferation. NK cell activity was measured by lactic acid dehydrogenase release assay. The effects of tramadol on thermal hyperalgesia were also assessed by measuring paw withdrawal latency (PWL) in the rats. PWL was dose-dependently reversed by tramadol after acute treatment (single subcutaneous injection) with 10, 20, and 30 mg/kg, respectively. There was no significant change among acute treatment groups in NK cell activity, whereas splenocyte proliferation induced by ConA and PHA was significantly suppressed starting from a dose of 20 mg/kg. The reversal of the thermal hyperalgesia persisted throughout a period of chronic tramadol treatment of 40 and 80 mg/kg per day, respectively, with continuous subcutaneous infusion for 7 days at a uniform rate via osmotic minipumps. No modulation of NK cell activity was found in either dose group. However, the activity of splenocyte proliferation was decreased in the 80 mg/kg per day group when compared with the saline and 40 mg/kg per day groups. These data suggest that tramadol treatment has an immunological profile different from pure mu-opioid agonists like morphine, which is known to suppress both NK cell activity and T lymphocyte proliferation at a subanalgesic dose in CCI rats. Considering analgesic and immunosuppressive effects, tramadol treatment may be a better choice than morphine for treatment of chronic neuropathic pain, particularly in patients with compromised immunity.

Influence of gamma irradiation and storage on apheresis platelets

BACKGROUND AND PURPOSE

Gamma irradiation of platelet concentrates to prevent graft-versus-host disease may inactivate contaminated lymphocytes and subsequently inhibit the synthesis of cytokines in the apheresis platelets during storage. We investigated the influence of irradiation and storage on apheresis platelets collected with the COBE Spectra or Fenwal CS-3000 Plus systems.

METHODS

Eleven units of apheresis platelets were collected with a COBE Spectra cell separator and another 11 units with a Fenwal CS-3000 Plus system. Each unit of apheresis platelets was divided into two equal parts: one was irradiated with 3000 cGy directly after blood donation, and the other served as a control. Cell counts, platelet activation marker CD62 antigen, blood gas values, and supernatant concentrations of K+, Na+, lactate, glucose, interleukin-1 beta (IL-1 beta), IL-8, and tumor necrosis factor-alpha (TNF-alpha) were determined in paired samples on the day of collection (day 0) and after 5 days of storage (day 5).

RESULTS

No significant differences in white cell counts or TNF-alpha concentrations were noted between the irradiated and control platelets on day 0 or day 5, whereas the mean proportion of platelets expressing CD62P (22.65% vs 25%, p = 0.014) and the mean IL-1 beta (45.55 pg/mL vs 52.75 pg/mL, p = 0.004) and IL-8 concentrations (10.68 pg/mL vs 13.07 pg/mL, p = 0.015) were significantly lower in irradiated than control platelets on day 5. The 5-day storage significantly increased the mean proportion of platelets expressing CD62P (25.00% vs 15.02%, p = 0.008), mean PO2 (116.34 mm Hg vs 98.07 mm Hg, p = 0.002), and mean concentrations of K+ (3.30 mmol/L vs 3.06 mmol/L, p < 0.001), lactate (15.12 mmol/L vs 3.23 mmol/L, p < 0.001), IL-1 beta (52.75 pg/mL vs 29.73 pg/mL, p = 0.001), and IL-8 (13.07 pg/mL vs 3.62 pg/mL, p < 0.001). Five-day storage also significantly decreased white cell count (0.18 x 10(8) vs 0.74 x 10(8), p < 0.001), PCO2 (19.38 mm Hg vs 50.51 mm Hg, p < 0.001), and concentrations of HCO3- (10.36 mmol/L vs 21.34 mmol/L, p < 0.001) and glucose (193.37 mg/dL vs 309.18 mg/dL, p < 0.001). Platelet counts and concentrations of IL-1 beta, IL-8, and TNF-alpha on day 0 did not differ significantly between control apheresis platelets collected with the Fenwal CS-3000 Plus and those collected with COBE Spectra. The mean white cell count (1.29 x 10(8) vs 0.19 x 10(8), p = 0.002) and the proportion of platelets expressing CD62P (24.71% vs 7.09%, p < 0.001) on day 0, however, were significantly higher in the platelets collected with the Fenwal CS3000-Plus than in those collected with the COBE Spectra.

CONCLUSIONS

Gamma irradiation of apheresis platelets inhibits the expression of platelet CD62P and the secretion of IL-1 beta and IL-8 after 5 days' storage.

Axillary brachial plexus block with patient controlled analgesia for complex regional pain syndrome type I: a case report

BACKGROUND AND OBJECTIVES

Brachial plexus block (BPB) has been cited as a treatment modality for complex regional pain syndrome type I (CRPS I) of the upper limb. However, there are no reports using axillary BPB with patient controlled analgesia (PCA) for the treatment of CRPS I. This report is based on the retrospective observations of the outcome and effects of axillary BPB with PCA in a patient with CRPS I.

CASE REPORT

A 32-year-old man suffered from CRPS I of the right upper limb after surgical release of carpal tunnel syndrome of the right hand. Symptoms and signs over the right hand were alleviated under rehabilitation and conventional pharmacological management, but severe painful swelling of the right wrist persisted. Axillary BPB with PCA was performed on the 32nd postoperative day, which soon resulted in significant reduction of pain with gradual improvement of function of the right wrist.

CONCLUSIONS

Axillary BPB with PCA may provide patients with CRPS I of the upper limb a feasible and effective treatment. .

Stability-indicating high-performance liquid chromatographic assay method and photostability of carprofen

A rapid, sensitive, and accurate stability-indicating high-performance liquid chromatographic assay method for determining the degradation of carprofen (CPF) is developed and validated under acidic, basic, or photo-irradiated conditions. The analysis is monitored with a Cosmosil 5C18-AR column using a mobile phase of CH3CN-H2O-AcOH (50:49:1, v/v/v) at 260 nm. The developed method satisfies the system suitability criteria, peak integrity, and resolution among the parent drug and its degradation products. The results indicate that the established assay method shows good selectivity and specificity suitable for stability measurements of CPF. CPF is found to be more sensitive to exposure to light and in acidic conditions, but it is stable in a basic medium. The kinetic study of the photodegradation of CPF follows an apparent first-order reaction in a variety of solvents. The solvent effects on the rates of degradation are in the decreasing order of chloroform > dichloromethane > methanol > ethanol > 2-propanol, which is irrelevant to the dielectric constant epsilon. However, the hydrogen-donating ability of the solvents is essential to the photochemical decomposition of CPF. A plot of log k versus the Kirkwood function exhibits a linear relationship in aqueous ethanolic solutions, which implies that degradation proceeds via an ionic mechanism.

Ectopic atrial tachycardia in children

BACKGROUND AND PURPOSE

Ectopic atrial tachycardia (EAT) is an unusual and potentially risky arrhythmia that can result in left ventricular dysfunction if not properly managed. In adults, EAT is mainly caused by diseased atrial myocardium and responds poorly to antiarrhythmic drugs. The characteristics of EAT in children might be different from those in adults because of their immature myocardium and the different electrophysiologic characteristics of their conduction tissue. We examined the natural history and treatment of EAT in children.

METHODS AND RESULTS

From June 1990 through June 1999, 24 children (8 girls and 16 boys; median age 4 mo [1 d-10 yr]) were admitted to our hospital with a diagnosis of EAT. Fifteen had healthy hearts, six had congenital heart disease, one had myocarditis, one had bronchopulmonary dysplasia with severe pulmonary hypertension, and one had hypertrophic cardiomyopathy. Thirteen patients presented with congestive heart failure. Only four patients had symptoms of prodromal airway infection. The maximum atrial rate was 244 +/- 66 beats per minute. Atrioventricular block was documented at least once during tachycardia in 10 patients. Warm-up or cool-down phenomenon was seen at the initiation or termination of tachycardia in thirteen patients. Primary pharmacologic treatment was attempted in all patients. EAT was initially controlled in all patients using digoxin plus propranolol (18 patients), propranolol only (4), or digoxin plus procainamide (2). EAT was controlled using medication in 22 patients. Fifteen patients had sinus rhythm but did not receive medication for 39 +/- 25 months. Two patients died of uncontrolled arrhythmia, and two of underlying disease. Recurrence was seen within 3 months after initial therapy in five patients. Surgery was performed to correct the underlying heart disease in three patients with frequently recurring EAT, all of whom remained tachycardia-free after surgery, without pharmacologic treatment. The spontaneous remission rate was 75% (18/24).

CONCLUSION

EAT in children without underlying heart disease can be effectively treated using antiarrhythmic drugs. Spontaneous resolution of EAT after medication in children was frequent (75%) in this series. The results of this study suggest that a step-wise approach using digoxin, a beta-blocker, and a class I antiarrhythmic drug may be the most effective treatment for EAT.

Dangerous impact--commotio cordis

Sudden death following blunt chest trauma is a frightening occurrence known as 'commotio cordis' or 'concussion of the heart'. It is speculated that commotio cordis could be caused by ventricular fibrillation secondary to an impact-induced energy that was transmitted via the chest wall to the myocardium during its vulnerable repolarization period. We describe a survivor of commotio cordis caused by a baseball. In this patient, an initial ventricular fibrillation was documented and converted by direct current defibrillation. Serial electrocardiographic changes (bifascicular conduction block and T wave inversion in precordial leads) were noticed in this patient. Our case suggested that coronary vasospasm might also play a role in commotio cordis.