Mutational analysis of basic residues in the rat vesicular acetylcholine transporter. Identification of a transmembrane ion pair and evidence that histidine is not involved in proton translocation

The function of positively charged residues and the interaction of positively and negatively charged residues of the rat vesicular acetylcholine transporter (rVAChT) were studied. Changing Lys-131 in transmembrane domain helix 2 (TM2) to Ala or Leu eliminated transport activity, with no effect on vesamicol binding. However, replacement by His or Arg retained transport activity, suggesting a positive charge in this position is critical. Mutation of His-444 in TM12 or His-413 in the cytoplasmic loop between TM10 and TM11 was without effect on ACh transport, but vesamicol binding was reduced with His-413 mutants. Changing His-338 in TM8 to Ala or Lys did not effect ACh transport, however replacement with Cys or Arg abolished activity. Mutation of both of the transmembrane histidines or all three of the luminal loop histidines showed no change in acetylcholine transport. The mutant H338A/D398N between oppositely charged residues in transmembrane domains showed no vesamicol binding, however the charge reversal mutant H338D/D398H restored binding. This suggests that His-338 forms an ion pair with Asp-398. The charge neutralizing mutant K131A/D425N or the charge exchanged mutant K131D/D425K did not restore ACh transport. Taken together these results provide new insights into the tertiary structure in VAChT.

Measurement of brake response time after right anterior cruciate ligament reconstruction

Recommendations on safe driving after anterior cruciate ligament (ACL) reconstruction have been largely intuitive. This study evaluated 12 male patients who underwent ACL reconstruction with subsequent outpatient rehabilitation and compared them with 10 subjects who had no knee dysfunction. The following clinical measures were assessed every 2 weeks for 10 weeks: brake response time (BRT), 6-meter walk time (6MWT), knee range of motion (ROM), pain (visual analog scale), and joint effusion. Statistical testing was completed using analysis of covariance with repeated measures. The results from treatment group were compared with norms from the AAA Traffic Safety and Engineering Department. BRT showed significant differences over 10 weeks (P =.043) in the study group. There were no significant differences between the study and control group based on condition (ACL reconstruction v control) (P =.586). Pain and effusion were found to have no significant interaction effect on BRT. The treatment group's BRT increased from the 25th percentile (AAA normals) to the 87th percentile after 10 weeks of rehabilitation. Although treatment group BRT was equal to AAA normal population BRT at week 4, the large improvement from week 2 to week 4 meant that learning effects could not be ruled out until week 6. Significant differences were found for 6MWT between week 2 and all other weeks (P <.0001). The results suggest brake reaction time matches control times at 4 to 6 weeks. Thus, BRT might be used to establish return to driving criteria (in part) after ACL reconstruction if other driving impediments do not exist.

An evaluation of mattresses and mats in two dairy units

In order to investigate the relative merits of mats and mattresses in terms of cow comfort, production and performance, 29 cows were housed on ethylethene vinyl acetate (EVA) mats and 29 on mattresses of loose rubber crumb with a polypropylene cover, at each of two similar dairy units (SAC Auchincruive and Myerscough). Both mats and mattresses were newly installed at the start of the trial. The cows were housed in the autumn after calving. Milk yield was recorded daily. Cows were weighed and scored for body condition, locomotion, dirtiness and hock and knee injury at fortnightly intervals. Feed offered was recorded daily and refusals were weighed weekly. Monthly milk records of milk yield, milk composition and somatic cell count data were available for both herds. In addition, 24 h behavioural observations of 15 core cows in each group were made at weeks 0, 2, 4, 6, 8, 16, and 32 post-housing. There was no difference between cows on mats and mattresses in milk yield, composition or quality; in feed intake; in weight loss or body condition score; in severe hock or knee injury, or in the incidence of lameness. Cows on mattresses tended to have slightly higher total dirtiness scores than those on mats (7.06 vs. 6.95, P=0.074) and had dirtier udders (mattress, 7.50 vs. mat, 6.52, P<0.05). However, over the whole housing period, cows on mattresses spent longer feeding, ruminating and lying and a greater proportion of their lying time was spent ruminating. They spent less time standing doing nothing (idling) than cows on mats and less time idling in cubicles. Cows on mattresses appeared to adapt to housing more quickly than those on mats. Overall, neither mat nor mattress gave advantages in terms of production or performance, cows were slightly cleaner on mats but behavioural indices suggest that cow comfort was greater on mattresses.

Extrafamilial sexual abuse: treatment for child victims and their families

OBJECTIVES

To decrease the emotional distress of child victims of extrafamilial sexual abuse (ESA) and their families. To provide crisis intervention, individual and group treatment in response to an expressed need in the community. To pilot the use of group treatment for child victims of ESA under age 10.

METHOD

This discussion describes intervention with a sample of 246 child victims, ages 2-14 years, and 323 parents who participated in the program from 1984 to 1991. This pilot project operated at a university medical facility and was located off campus in an outpatient child abuse center. Priority was given to child victims under age 7. Child victims and their families were evaluated after investigative interviews by law enforcement agencies were completed. A treatment plan was developed based on clinical assessment. Families participated in crisis counseling, individual treatment for the child victim and/or parent, Children's Treatment Groups, Parent Support Groups, or were referred to other resources. Clinical assessment of treatment progress included weekly case review by child and parent therapists, video analysis and observation of Children's Treatment Group sessions, consultation with parents and collateral contacts.

RESULTS

A family approach and services for parents in addition to intervention for child victims were determined to be key components in facilitating recovery. Clinical observations and client feedback showed positive outcomes for child victims and parents with crisis counseling, Children's Treatment groups, and Parent Support Groups. The extent of intervention ranged from one session to 24 months with an average participation of 6-9 months. Follow up surveys were returned by parents for 48 child victims and results are reported. Themes, parallels in responses, and recovery factors for child victims and parents are discussed.

CONCLUSIONS

The need for intervention and a community-based program was demonstrated by (1) the significant disruption in functioning that occurred for child victims of ESA and their families, (2) the risk for long term sequelae, (3) the high incidence of extrafamilial sexual abuse, and 4) the consistent, large number of requests for services. Family-centered crisis services, Children's Treatment Groups, and Parent Support Groups can be effectively based at child advocacy centers, out patient care clinics, or other community agencies. The results of formal outcome measures and longitudinal studies is needed to determine how child victims and parents benefit from specific treatment modalities and to better guide the use of limited resources.

Comparison of costing tools in paediatric intensive care

The cost of service provision is an issue of concern to all professionals working in health care. Department of Health reports have highlighted the need for more effective costing mechanisms for provision of paediatric intensive care (PIC). This study aimed to determine whether nurse-patient dependency scoring would be as effective as the Therapeutic Intervention Scoring System (TISS) at providing a differential costing tool for PIC. Data were collected on 251 patient admissions over 1,741 nursing shifts and analysis of variance undertaken. Findings suggest that a modified nurse-patient dependency score would be as good as TISS as a potential costing tool in PICU.

Solution structure of the receptor tyrosine kinase EphB2 SAM domain and identification of two distinct homotypic interaction sites

The sterile alpha motif (SAM) is a protein interaction domain of around 70 amino acids present predominantly in the N- and C-termini of more than 60 diverse proteins that participate in signal transduction and transcriptional repression. SAM domains have been shown to homo- and hetero-oligomerize and to mediate specific protein-protein interactions. A highly conserved subclass of SAM domains is present at the intracellular C-terminus of more than 40 Eph receptor tyrosine kinases that are involved in the control of axonal pathfinding upon ephrin-induced oligomerization and activation in the event of cell-cell contacts. These SAM domains appear to participate in downstream signaling events via interactions with cytosolic proteins. We determined the solution structure of the EphB2 receptor SAM domain and studied its association behavior. The structure consists of five helices forming a compact structure without binding pockets or exposed conserved aromatic residues. Concentration-dependent chemical shift changes of NMR signals reveal two distinct well-separated areas on the domains' surface sensitive to the formation of homotypic oligomers in solution. These findings are supported by analytical ultracentrifugation studies. The conserved Tyr932, which was reported to be essential for the interaction with SH2 domains after phosphorylation, is buried in the hydrophobic core of the structure. The weak capability of the isolated EphB2 receptor SAM domain to form oligomers is supposed to be relevant in vivo when the driving force of ligand binding induces receptor oligomerization. A formation of SAM tetramers is thought to provide an appropriate contact area for the binding of a low-molecular-weight phosphotyrosine phosphatase and to initiate further downstream responses.

Swinholides and new acetylenic compounds from an undescribed species of Theonella sponge

Four new acetylenic compounds, 5-8, along with four known ones, 1-4, were isolated from a sponge, Theonella sp., collected in Chuuk Atoll, Federated States of Micronesia. Three unrelated swinholide-type compounds were also isolated. The structures of the new acetylenes were determined from spectral data and chemical degradation.

Improved bladder function after prophylactic treatment of the high risk neurogenic bladder in newborns with myelomentingocele

PURPOSE

High pressure dyssynergic voiding may result in irreversible damage to the urinary tract. Prophylactic therapy in the form of clean intermittent catheterization and anticholinergic medication may significantly decrease the incidence of upper urinary tract deterioration. Whether prophylactic therapy in the high risk bladder may also lead to improved long-term bladder dynamics prompted us to study the effect of early versus late treatment of bladder hypertonicity and detrusor-sphincter dyssynergia on the ultimate need for bladder augmentation.

MATERIALS AND METHODS

We retrospectively reviewed urological outcomes in patients with myelodysplasia who were at risk for urological deterioration within year 1 of life based on bladder sphincter dyssynergia and/or high filling or voiding pressure. We recorded the dates when high risk voiding dynamics were initially observed, and when intermittent catheterization and anticholinergic therapy were initiated. Patients in whom treatment began at the time a high risk profile was noted (prophylactic group seen between 1985 and 1990) were compared to controls with the same high risk voiding parameters who did not receive early therapy (observation group seen between 1978 and 1984 with therapy instituted 1 year or longer after high risk was noted). The number of augmentations performed in each group was indexed to the total number of years of followup in the 2 populations, respectively. Patients with less than 2 years of followup were excluded from further analysis.

RESULTS

Of the 45 patients at risk clean intermittent catheterization and anticholinergic medication were immediately initiated in 18, while 27 were treated expectantly. Patients in the observation group were followed an average of 4.1 years (range 1.1 to 14) before clean intermittent catheterization and anticholinergic medication were started. Of the 27 children treated expectantly 11 (41%) required augmentation, whereas only 3 of the 18 (17%) treated prophylactically required enterocystoplasty. When the number of augmentations was indexed to total years of followup in each of the 2 groups (296 versus 156 years) patients in the expectant group were nearly twice as likely to require augmentation.

CONCLUSIONS

Identification and early proactive treatment of the high pressure, dyssynergic lower urinary tract significantly decreases the need for bladder augmentation as children with neurogenic bladder secondary to myelomeningocele mature.

New nitrogenous bisabolene-type sesquiterpenes from a micronesian marine sponge, axinyssa species

Chemical investigation of an Axinyssa species of sponge collected at Yap Island afforded three new nitrogenous sesquiterpenes, 1-3, together with the known compound 3-formamidotheonellin (4). The structures of compounds 1, 3, and 4 were confirmed by spectroscopic methods, and compound 2 was tentatively identified by comparison of its (1)H and (13)C NMR data with those of 1, 3, and 4 and (1)H decoupling experiments.

Exploring young men's drinking using the AUDIT questionnaire

This paper reports the findings of an AUDIT questionnaire administered to a sample of young (16-24-year-old) white males. Of the sample, 65% were drinking at potentially harmful levels. Averaging 45 U/week, 18-21 years was the age of highest alcohol consumption. Compared with 16-17- and 22-24-year-olds, this group recorded the highest proportion of hazardous drinkers and most negative consequences of drinking.

Cloning, chromosomal location, and expression analysis of murine Smarce1-related, a new member of the high-mobility 365 group gene family

Proteins containing high-mobility group (HMG) domains are segregated into two major groups. Members of one group are identified by the presence of more than one HMG domain that binds to DNA without sequence specificity, and they are usually ubiquitously expressed. In contrast, members of the other group possess a single HMG domain with high affinity to specific DNA sequences. Generally, members of the second group resemble classic tissue-specific transcriptional regulators. In contrast, Smarce1/BAF-57 is a ubiquitously expressed, novel protein with a single HMG domain that displays nonspecific DNA-binding characteristics. Additionally, as a core subunit of the mammalian SWI/SNF-like transcriptional activator complex, Smarce1/BAF-57 is also the first member of the HMG protein family that was reported to contain a kinesin-like coiled-coil (KLCC) domain. Here we report the cloning, as well as the chromosomal and phylogenetic analysis, of a novel mammalian protein that is structurally related to Smarce1, termed Smarce1-related (Smarce1r). The unique arrangement of an HMG with a KLCC domain shared with Smarce1/BAF-57 suggests a similar, albeit still unknown, function in chromatin assembly as part of a mammalian SWI/SNF-like complex. The linkage of a single nonspecific DNA-binding HMG domain with a KLCC domain makes both proteins the founding members of a third group of HMG proteins.

Normal urodynamics in patients with bladder exstrophy: are they achievable?

PURPOSE

Urodynamic study was performed in patients with exstrophy to determine the effect of bladder neck reconstruction and the ability to achieve normal urodynamics following surgery.

MATERIALS AND METHODS

A total of 30 exstrophy cases at different stages of reconstruction were retrospectively reviewed in terms of bladder capacity, compliance, stability and presence of detrusor contractions following urodynamic study.

RESULTS

Bladder capacity increased from a third predicted volume for age to half after reconstruction. Approximately 80% of patients had compliant and stable bladders before bladder neck reconstruction. Following bladder neck reconstruction approximately half of the patients maintained normal compliance with a smaller number maintaining normal stability. A quarter of patients maintained normal filling dynamics following bladder neck reconstruction, and 19% maintained normal filling and voiding dynamics after reconstruction.

CONCLUSIONS

The majority of closed exstrophy bladders have normal filling dynamics before bladder neck reconstruction. Compliance and stability are impaired following bladder neck reconstruction. Approximately 25% of patients with exstrophy may maintain normal detrusor function following reconstruction. However, less invasive alternatives to the Young-Dees-Leadbetter bladder neck reconstruction should be sought.

Halisulfate 7, a new sesterterpene sulfate from a sponge, Coscinoderma sp

A new sesterterpene sulfate, halisulfate 7 (1), has been isolated from a Coscinoderma sp. of sponge collected at Yap, Federated States of Micronesia. The structure was determined from spectroscopic evidence.

Stereotactic cyst wall disruption and aspiration of colloid cysts of the third ventricle

BACKGROUND

Current strategies of surgical therapy for colloid cysts have been associated with low rates of initial success and high rates of morbidity, mortality and recurrence of cysts. Cyst recurrence following simple stereotactic aspiration has been hypothesized to be due to regrowth of the epithelium composing the cyst wall.

METHODS

We propose a procedure involving stereotactic disruption of the colloid cyst wall with the removal of a portion of the cyst wall followed by aspiration of cyst contents as a surgical therapy for colloid cysts.

RESULTS

This procedure was performed in 2 female and 3 male patients who were followed for an average of 49 months with all patients demonstrating immediate improvement of symptoms and resolution of the cyst verified with repeat computerized tomography (CT) scans. There was one incidence of recurrence in an asymptomatic patient at 75 months postoperatively.

CONCLUSION

We propose that stereotactic partial cyst wall disruption and content aspiration may limit recurrence of colloid cysts, thus offering an advantage over simple stereotactic aspiration alone.

Construction of gene targeting vectors from lambda KOS genomic libraries

We describe a highly redundant murine genomic library in a new lambda phage, lambda knockout shuttle (lambda KOS) that facilitates the very rapid construction of replacement-type gene targeting vectors. The library consists of 94 individually amplified subpools, each containing an average of 40,000 independent genomic clones. The subpools are arrayed into a 96-well format that allows a PCR-based efficient recovery of independent genomic clones. The lambda KOS vector backbone permits the CRE-mediated conversion into high-copy number pKOS plasmids, wherein the genomic inserts are automatically flanked by negative-selection cassettes. The lambda KOS vector system exploits the yeast homologous recombination machinery to simplify the construction of replacement-type gene targeting vectors independent of restriction sites within the genomic insert. We outline procedures that allow the generation of simple and more sophisticated conditional gene targeting vectors within 3-4 weeks, beginning with the screening of the lambda KOS genomic library.

Do iron and vitamin C co-supplementation influence platelet function or LDL oxidizability in healthy volunteers?

OBJECTIVE

To examine the effect of co-supplementation with iron and vitamin C on antioxidant status, platelet function and low density lipoprotein oxidation in normal healthy volunteers.

DESIGN

The study was carried out with two groups of 20 subjects each acting as their own control, comparing presupplemention with postsupplemention. One group was supplemented with iron and the RDA level of vitamin C and the second group with iron and 260 mg/d vitamin C.

SETTING

The International Antioxidant Research Centre, The Guy's, King's College and St Thomas's School of Biomedical Science, Guy's Campus, London.

SUBJECTS

Forty normal healthy volunteers, recruited from the staff of the Medical School and Hospital in which two volunteers withdrew during the study.

INTERVENTIONS

Subjects in both studies were randomly assigned to one of two groups (5 males and 5 females group) and received supplements containing iron (14 mg/d) and either 60 mg/d (Group A) or 260 mg/d (Group B) vitamin C for 12 wk. Blood samples were taken at 6 wk and 12 wk, and prior to supplementation and analysed for iron and antioxidant status (transferrin bound iron, vitamin C and E, and beta-carotene levels) in both studies. Samples from the first study were analysed for the susceptibility of LDL isolated from plasma to Cu2+-induced oxidation and samples from the second for platelet function.

RESULTS

Transferrin-bound iron was significantly increased (P < 0.05) at 12 wk, in Group A subjects (from 14.9+/-5.3 micromol/1 to 19.5+/-2.3 micromol/l; mean+/-s.d.; n=19), whereas those in Group B showed a significant increase (P < 0.05) after 6 wk (from 15.8+/-4.5 micromol/l to 20.4+/-6.6 micromol/l; n = 19) which decreased at 12 wk (16.3+/-5.0 micromol/l). Plasma total ascorbate significantly increased from an initial level of 59.3+/-21.3 micromol/l to 87.6+/-29.0 micromol/l after 6 wk and 81.7+/-11.4 micromol/l after 12 wk following the Group B supplementation, but only after 12 wk in Group A (from 64.0+/-24.8 micromol/l to 77.2+/-13.2 micromol/l). Plasma alpha-tocopherol concentrations were significantly increased after 6 wk and 12 wk with both levels of supplementation (from 24.2+/-5.71 micromol/l Group A and 23.4+/-5.3 micromol/l Group B to 26.3+/-5.5 micromol/l and 25.71+/-4.7 micromol/1 respectively at 12wk). The mean lag phase to oxidation of low density lipoprotein (LDL) was significantly increased in subjects in Group B after 12 wk ingestion of iron and 260 mg vitamin C (from 80.0+/-14.8 min to 97.2+/-16.9 min; n = 9). Platelet sensitivity to ADP-induced aggregation was significantly decreased (P < 0.05) by 12 wk in Group A (from EC50 2.3 < or = 1.3 microM to 3.7+/-2.2 microM; n = 10), whereas those receiving higher vitamin C showed a significant decrease (P < 0.05; from EC50 1.9+/-0.6 microM to 3.1+/-1.8 microM) after 6wk which subsequently increased towards presupplemental levels (2.6+/-1.6 microM). Platelets from the latter subjects showed a significant reduction in ADP-induced ATP secretion at both 6wk and 12 wk.

CONCLUSION

The results show modest beneficial effects on LDL oxidation and platelet function following supplementation with iron and vitamin C. No evidence for pro-oxidant effects was observed.

Prat falls, missteps, & solutions in implementing change

Agencies across the country are preparing for OASIS, PPS, and other changes. The Visiting Nurse Association of Northern California shares its story of preparing for changes while simultaneously shifting gears to achieve compliance with regulations amid competing priorities and financial pressures.

Vascular surgical society of great britain and ireland: review of out-of-hours vascular procedures in a tertiary vascular unit

BACKGROUND: The aim of this study was to review out-of-hours vascular procedures in a tertiary vascular unit. METHODS: The vascular emergencies that presented outside normal working hours (17. 00 to 08.00 hours) in a vascular unit between January and June 1998 were reviewed. Only cases considered to be life or limb threatening and requiring urgent surgical or radiological intervention were assessed. RESULTS: The Table shows that a significant number of vascular emergencies was performed out of hours in one unit. This was, in part, due to an increase in the number of tertiary referrals, which represented 57 per cent of all emergency procedures. Reasons for the tertiary referrals were: no consultant vascular surgeon on call (33 per cent), no consultant interventional radiologist on call (26 per cent), lack of intensive care beds (30 per cent) and complex procedure (11 per cent). The overall mortality rate of patients referred in this period was 15 per cent. The unit has three consultant vascular surgeons, two consultant interventional radio- logists and one vascular specialist registrar. CONCLUSION: The significant increase in out-of-hours vascular emergencies, both surgical and radiological, has placed an enormous demand on senior members of the team. In addition, it has had a significant impact on the unit's elective admissions and waiting lists, in particular those for routine general surgery. To support the growth in complex emergency referrals, senior vascular fellows in both vascular surgery and radiology have been appointed and proposals are underway to restructure local vascular services.

NMR studies on the 46-kDa dimeric protein, 3,4-dihydroxy-2-butanone 4-phosphate synthase, using 2H, 13C, and 15N-labelling

3,4-Dihydroxy-2-butanone 4-phosphate synthase catalyses the release of C-4 from the substrate, ribulose phosphate, via a complex series of rearrangement reactions. The cognate ribB gene of Escherichia coli was hyperexpressed in a recombinant E. coli strain. The protein was shown to be a 46-kDa homodimer by hydrodynamic analysis. A variety of protein samples labelled with different grades of 13C, 15N and 2H, i.e. one with 100% 2H and 15N, one with 75% 2H, 99% 13C, 15N, and one with 100% 2H, 99% 13C,15N were prepared. Despite the large molecular size, 2- and 3-dimensional NMR spectra of reasonable quality were obtained. Attempts at the assignment of individual 13C, 15N and 1H signals show, in principle, the feasibility of structure determination. The number of NMR signals shows unequivocally that the homodimeric protein obeys strict C2 symmetry.

Molecular cloning and phylogenetic analysis of the small cytoplasmic RNA from Listeria monocytogenes

A molecular cloning strategy has been designed to isolate the gene that encodes the small cytoplasmic RNA (scRNA) component of bacterial signal recognition particles. Using this strategy a putative Listeria monocytogenes scRNA lambda gt11 recombinant clone was isolated. A previously described complementation assay developed to genetically select functional homologues of 4.5S RNA and scRNA of bacteria confirmed that the lambda gt11 recombinant clone isolated encoded for the scRNA from L. monocytogenes. A secondary structure for this scRNA is proposed and a phylogenetic comparison of the 276 base L. monocytogenes scRNA with previously characterised Gram-positive bacterial scRNAs is also presented.