Differences in the use of vision and proprioception for postural control in autism spectrum disorder.

BACKGROUND: People with autism spectrum disorders (ASDs) also have poorer fundamental motor skills. The development of postural control underlies both social and motor skills. All three elements are facilitated by the active use of visual information. This study compares how adults with ASD and typically developed adults (TDAs) respond to a postural illusion induced using neck vibration. Adults with ASD unlike the TDA, were not expected to correct the illusion using vision. METHODS: The study used intermittent (15off, 5on) posterior neck vibration during 200 s of quiet stance to induce a postural illusion. In TDAs and only in the absence of vision this protocol induces a forward body lean. Participants (12 ASD, 20 TDA) undertook four conditions combining vibration and visual occlusion. RESULTS: As predicted, TDA were only affected by the postural illusion when vision was occluded (vibration condition: vision occluded (n=1) p=0.0001; vision available (n=3) p>0.2466). Adults with ASD were affected by the postural illusion regardless of the availability of vision (all conditions p<0.0007). CONCLUSIONS: Our findings indicated the adults with ASD did not use visual information to control standing posture. In light of existing evidence that vision-for-perception is processed typically in ASD, our findings support a specific deficit in vision-for-action. These findings may explain why individuals with ASD experience difficulties with both social and motor skills since both require vision-for-action. Further research needs to investigate the division of these visual learning pathways in order to provide more specific intervention opportunities in ASD.

Open reduction and plate fixation versus nonoperative treatment for displaced midshaft clavicular fractures: a multicenter, randomized, controlled trial.

BACKGROUND: There is a growing trend to treat displaced midshaft clavicular fractures with primary open reduction and plate fixation; whether such treatment results in improved patient outcomes is debatable. The aim of this multicenter, single-blinded, randomized controlled trial was to compare union rates, functional outcomes, and economic costs for displaced midshaft clavicular fractures that were treated with either primary open reduction and plate fixation or nonoperative treatment. METHODS: In a prospective, multicenter, stratified, randomized controlled trial, 200 patients between sixteen and sixty years of age who had an acute displaced midshaft clavicular fracture were randomized to receive either primary open reduction and plate fixation or nonoperative treatment. Functional assessment was conducted at six weeks, three months, six months, and one year with use of the Disabilities of the Arm, Shoulder and Hand (DASH) and Constant scores. Union was evaluated with use of three-dimensional computed tomography. Complications were recorded, and an economic evaluation was performed. RESULTS: The rate of nonunion was significantly reduced after open reduction and plate fixation (one nonunion) as compared with nonoperative treatment (sixteen nonunions) (relative risk = 0.07; p = 0.007). Group allocation to nonoperative treatment was independently predictive of the development of nonunion (p = 0.0001). Overall, DASH and Constant scores were significantly better after open reduction and plate fixation than after nonoperative treatment at the time of the one-year follow-up (DASH score, 3.4 versus 6.1 [p = 0.04]; Constant score, 92.0 versus 87.8 [p = 0.01]). However, when patients with nonunion were excluded from analysis, there were no significant differences in the Constant scores or DASH scores at any time point. Patients were less dissatisfied with symptoms of shoulder droop, local bump at the fracture site, and shoulder asymmetry in the open reduction and plate fixation group (p < 0.0001). The cost of treatment was significantly greater after open reduction and plate fixation (p < 0.0001). CONCLUSIONS: Open reduction and plate fixation reduces the rate of nonunion after acute displaced midshaft clavicular fracture compared with nonoperative treatment and is associated with better functional outcomes. However, the improved outcomes appear to result from the prevention of nonunion by open reduction and plate fixation. Open reduction and plate fixation is more expensive and is associated with implant-related complications that are not seen in association with nonoperative treatment. The results of the present study do not support routine primary open reduction and plate fixation for the treatment of displaced midshaft clavicular fractures.

Risk factors for nonunion after nonoperative treatment of displaced midshaft fractures of the clavicle.

BACKGROUND: Identification of patients at higher risk of nonunion after diaphyseal clavicular fractures is desirable to improve patient counseling and enable targeted surgical treatment. METHODS: Seventy-nine percent (941 of 1196) of diaphyseal clavicular fractures were followed to union or nonunion. Demographic, injury, and radiographic characteristics associated with nonunion were determined with use of bivariate and multivariate statistical analyses. RESULTS: In patients who were eighteen years of age or older, 125 (13.3%) of the fractures had clinical and radiographic evidence of nonunion. Factors significantly associated with nonunion on bivariate analysis were sex, smoking status, overall fracture displacement, overlap, translation, and comminution. The factors that maintained significance on multivariate analysis were smoking (odds ratio, 3.76), comminution (odds ratio, 1.75), and fracture displacement (odds ratio, 1.17). If all displaced midshaft fractures were managed operatively, 7.5 procedures would need to be undertaken to prevent a single nonunion. If only fractures with a predicted probability of ≥40% were managed operatively, the number of patients managed operatively to prevent a single nonunion would fall to 1.7. CONCLUSIONS: Thirteen percent of displaced diaphyseal fractures in patients who were at least eighteen years of age did not heal. Smoking was the strongest risk factor, and smoking cessation should be an integral part of treatment. The probability of nonunion in a particular individual can be estimated with use of a statistical model based on known risk factors. This information can be useful when counseling the patient even though nonunion remains difficult to predict accurately in that individual. The number who would need to be treated to prevent a single nonunion can be reduced by identifying those at higher risk.

Infant HIV infection despite "universal" antenatal testing.

We reviewed the antenatal HIV testing history, clinical presentation and outcome of 25 infants diagnosed with HIV between 1 January 2001 and 31 December 2005 in a tertiary referral hospital in London. Of the 25 cases, 21 had received antenatal care in the UK. Twelve mothers had not had an antenatal HIV test, four had tested positive antenatally, while five had had a negative HIV test on antenatal booking, implying seroconversion in pregnancy. When mothers had not been diagnosed antenatally, infants presented with severe infections, which were fatal in six cases. The majority (65%) of the children have long-term neurological sequelae. HIV seroconversion is an important cause of infant HIV in the UK.

Bell inequalities for continuous-variable correlations.

We derive a new class of correlation Bell-type inequalities. The inequalities are valid for any number of outcomes of two observables per each of n parties, including continuous and unbounded observables. We show that there are no first-moment correlation Bell inequalities for that scenario, but such inequalities can be found if one considers at least second moments. The derivation stems from a simple variance inequality by setting local commutators to zero. We show that above a constant detector efficiency threshold, the continuous-variable Bell violation can survive even in the macroscopic limit of large n. This method can be used to derive other well-known Bell inequalities, shedding new light on the importance of non-commutativity for violations of local realism.

HIV in pregnancy: evolution of clinical practice in the UK.

Prior to the introduction of interventions reducing mother-to-child transmission of HIV-1 natural history data reports vertical transmission rates in the order of 25%. The risk of transmission from mother-to-child has been associated with advanced maternal HIV disease, maternal plasma HIV viral load and CD4 lymphocyte count, mode of delivery, length of rupture of membranes, prematurity and breast feeding. During the last 10-15 years the introduction of prelabour cesarean section, formula feeding and antiretroviral therapy has reduced transmission to less than 1% for pregnant women in the UK who are aware of their HIV status. Attention is now turning to the minimization of possible drug side effects for both mother and infant as women are increasingly conceiving on combination antiretroviral therapy. The evolution of current UK guidelines on the prevention of mother-to-child transmission of HIV-1 are discussed.

Neurodevelopmental outcomes in children with HIV infection under 3 years of age.

Following the introduction of combination antiretroviral therapy, children vertically infected with the human immunodeficiency virus (HIV-1) living in the developed world are surviving into adult life. This paper reviews the neurodevelopmental outcomes of 62 consecutively-presenting children with HIV-1 infection diagnosed before 3 years of age (32 males, 30 females; median age at presentation 6 mo). Neurological and developmental data are presented with immunological and virological responses to antiretroviral therapy. Fourteen children (22%) had abnormal neurological signs and 25 (40%) demonstrated significant developmental delay on standardized developmental assessments. Children presenting with more severe HIV-1 disease and immune compromise had significantly more abnormal neurological signs and developmental delays than children presenting with milder HIV-1 symptomatology. Immune function, control of HIV-1 viral replication, and growth parameters improved with antiretroviral therapy (median age at last follow-up 7 y 3 mo); however, abnormal neurological signs and significant gross motor difficulties persisted.

Potent, low molecular weight thrombin receptor antagonists.

Several benzimidazole derivatives have been identified as potent thrombin receptor (PAR-1) antagonists as represented by compound 1h, which showed an IC(50) of 33 nM.

Molecular identification and characterization of the platelet ADP receptor targeted by thienopyridine antithrombotic drugs.

ADP plays a critical role in modulating thrombosis and hemostasis. ADP initiates platelet aggregation by simultaneous activation of two G protein-coupled receptors, P2Y1 and P2Y12. Activation of P2Y1 activates phospholipase C and triggers shape change, while P2Y12 couples to Gi to reduce adenylyl cyclase activity. P2Y12 has been shown to be the target of the thienopyridine drugs, ticlopidine and clopidogrel. Recently, we cloned a human orphan receptor, SP1999, highly expressed in brain and platelets, which responded to ADP and had a pharmacological profile similar to that of P2Y12. To determine whether SP1999 is P2Y12, we generated SP1999-null mice. These mice appear normal, but they exhibit highly prolonged bleeding times, and their platelets aggregate poorly in responses to ADP and display a reduced sensitivity to thrombin and collagen. These platelets retain normal shape change and calcium flux in response to ADP but fail to inhibit adenylyl cyclase. In addition, oral clopidogrel does not inhibit aggregation responses to ADP in these mice. These results demonstrate that SP1999 is indeed the elusive receptor, P2Y12. Identification of the target receptor of the thienopyridine drugs affords us a better understanding of platelet function and provides tools that may lead to the discovery of more effective antithrombotic therapies.

Is coronary angioplasty safe in the elderly?

OBJECTIVE: To evaluate the use of percutaneous transluminal coronary angioplasty (PTCA) and the immediate procedural outcomes in the elderly at a tertiary care centre. PATIENTS AND METHODS: Between January 1992 and December 1997, a total retrospective cohort study of 2322 consecutive patients aged 60 years or older underwent PTCA. Patients were categorized into three age groups: group A (60 to 69 years of age), which included 1294 patients; group B (70 to 79 years), which included 895 patients; and group C (80 years of age or older), which included 133 patients. PTCA was performed using the newest catheter technology as it became available. RESULTS: Men comprised 63% of the patients in groups A and B combined, and 44% of group C (P<0.001). Canadian Cardiovascular Society angina class IV was present in 45% of group C compared with 30% and 35% in groups A and B, respectively (P<0.001). The proportion of patients with diabetes mellitus and hypertension was similar among the three groups. Acute myocardial infarction before PTCA was twice as common at 4.5% (95% CI 3.7% to 5.3%) in group C, compared with 2.9% (95% CI 2.7% to 3.1%) and 2.2% (95% CI 2.0% to 2.3%) in groups A and B, respectively. The procedural success rate was similar at 93%, 92.7% and 91.7% in groups A, B and C, respectively. A total of five (0.2%) deaths and eight (0.34%) myocardial infarctions occurred in groups A and B combined, while none occurred in group C (not significant). More patients in groups A and B underwent emergency coronary artery bypass graft than in group C: group A - 22, 3.4% (95% CI 3.2% to 3.6%); group B - 16, 3.4% (95% CI 3.2% to 3.6%) and group C - one, 0.75% (95% CI 0.6% to 0.9%). CONCLUSIONS: In this retrospective series of patients, it was shown that PTCA may be performed in the very elderly with high procedural success and acceptable risk. Age alone should not be the criterion to limit the use of PTCA.

Exclusion of a p53 germline mutation in a classic Li-Fraumeni syndrome family.

Li-Fraumeni syndrome (LFS) is characterized by a high risk of sarcomas, early onset of breast cancer, and a diversity of other cancers occurring as multiple primary tumors in multiple family members. In many families with LFS, germline mutations within the tumor-suppressor gene p53 have been identified. However, mutations in p53 have not been detected in approximately 30% of LFS families. To address the possibility either that p53 mutations were being missed or that another predisposing gene is altered in LFS, we used a variety of methods to accurately determine the p53 status in a large LFS kindred. A transcriptional activation assay on exons 4-10 of p53 excluded a mutation within the DNA-binding domain of p53. Single-stranded conformational-polymorphism analysis, using intronic primers and sequencing of all the coding exons and intron/exon junctions, also yielded no mutations. Finally, linkage analysis excluded potential mutations in the noncoding regions of p53. Our findings exclude the presence of a p53 germline mutation in a classic LFS family.

Community care outcomes.

A community care scheme was designed to provide an alternative to residential care by the flexible use of informal paid carers to supplement or replace formal care. We report details of client problems and dependency, outcomes and use of hospital inpatient beds for the first 92 clients. The mean age was 83 years (28 men, 64 women). In all, 88/92 suffered from dementia. The CAPE survey dependency of the clients was A 2%, B 8%, C 23%, D 40%, E 27%. The 1-year outcome was 50% at home, 25% died, 10% part III, 15% long-term care; at 3 years: 24% at home, 64% dies, 7% part III, 6% long-term care. In the year before admission to the scheme, 58% were admitted to hospital, totalling 139 patient months in hospital, and in the first year of the scheme 55% were admitted, spending 82 patient months in hospital. Frail elderly people supported at home have a significant mortality and morbidity rate, and continue to need a high use of NHS inpatient resources.

Mercaptoacyl amino acid inhibitors of atriopeptidase. 1. Structure-activity relationship studies of methionine and S-alkylcysteine derivatives.

A broad series of N-(3-mercaptoacyl) amino acid derivatives was evaluated for their ability to inhibit atriopeptidase (neutral endopeptidase, EC 3.4.24.11) in vitro and in vivo. Structural parameters studied were (i) the substituent on the 2-position of the 3-mercaptopropionyl moiety, (ii) the amino acid component, (iii) the S-terminal derivative, and (iv) the C-terminal derivative. Optimum activity was observed for derivatives of methionine and S-alkylcysteines. N-[3-Mercapto-2(S)-[(2-methylphenyl)methyl]-1-oxopropyl]-L-methionine was identified as a highly effective inhibitor of atriopeptidase meriting evaluation as a potential cardiovascular therapeutic agent.

Does the speed of balloon deflation affect the complication rate of coronary angioplasty?

Two hundred consecutive coronary arteries in 157 patients undergoing angioplasty were randomized to fast or slow balloon deflation. Angioplasty was successful in 188 cases (101 with slow and 87 with fast deflation). There was no significant difference between the 2 groups with regard to the total number of dissections, although there was a greater number in the slow deflation group, and no difference in the number of minor dissections (National Heart, Lung, and Blood Institute types A and B). There was a significantly greater number of more severe dissections (types C to F) in the slow deflation group (20 vs 5; p = 0.013). It is proposed that the greater number of severe dissections is due to either increased turbulence or movement of the partially deflated balloon during slow deflation. Thus, slow balloon deflation during coronary angioplasty is associated with a higher complication rate than is conventional rapid deflation.

Anaesthesia for the patient with neonatal adrenoleukodystrophy.

The authors present and discuss the care of a nine-month-old with neonatal adrenoleukodystrophy who required general anaesthesia for gastrointestinal endoscopy. Neonatal adrenoleukodystrophy is an inherited disorder of peroxisomal enzymes. Anaesthetic care may be affected by the presence of hypotonia, liver function abnormalities, gastroesophageal reflux, and impaired adrenocortical function. Preoperative sedation is contraindicated because of the risk of precipitating airway obstruction due to pre-existing hypotonia. Anaesthetic induction and tracheal intubation should be performed to minimize the risk for aspiration of gastric contents. The choice of muscle relaxant should take into account the pre-existing hypotonia as well as the possibility of hyperkalaemia in response to succinylcholine. Anaesthetic agents known to decrease the seizure threshold should be avoided in patients with a seizure disorder. In addition, anaesthetic agents that rely on the liver for metabolism should be used with caution in patients with cirrhosis. When time permits, these patients should be screened for adrenocortical insufficiency before surgery, and perioperative steroid coverage is advisable when preoperative testing of adrenocortical function is not feasible. While these patients eventually die after progressive deterioration, full recovery from the effects of anaesthesia and surgery can be achieved with attention to neurological, metabolic, and physical problems.

Comparison of fixed-wire and over-the-wire balloon dilatation systems for percutaneous transluminal coronary angioplasty.

There is controversy concerning the relative safety and efficacy of the 2 currently available percutaneous transluminal coronary angioplasty dilatation systems--fixed-wire (FW) and over-the-wire (OW). A randomized, prospective trial comparing the 2 systems was performed to examine this controversy. Of 1,513 patients undergoing percutaneous transluminal coronary angioplasty at 3 centers between June 1990 and October 1991, 602 (40%) fulfilled the eligibility criteria for the study. There were 643 lesions, of which 327 were randomized to FW and 316 to OW systems. There was no difference in the success rate between FW (92%) and OW (94%) systems. Inability to cross with a wire was infrequent with either system (FW: 1.8%; and OW: 1.6%). Inability to cross with a balloon when the wire crossed the lesion did not occur. An FW system was successful in 6 cases (1.9%) in which the OW system had been unsuccessful, whereas an OW system succeeded in 14 (4.3%) after the FW system had been unsuccessful (p = NS). Time to cross stenoses was 200 +/- 21 and 233 +/- 22 seconds, procedural time was 21 +/- 1.3 and 21 +/- 1.0 minutes, fluoroscopy time was 6.7 +/- 0.4 and 7.1 +/- 0.4 minutes, contrast used was 89.0 +/- 4.2 and 84.0 +/- 3.5 ml, and number of cine runs was 5.9 +/- 3.0 and 6.3 +/- 3.4 in the FW and OW systems, respectively. Complications were infrequent with either system (FW: 10.4%; and OW: 9.5%). Acute closure occurred in 1.8 and 2.2% of cases in the FW and OW systems, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulation of circulating endothelin levels in hypertension and endotoxemia in rats.

We have developed separate radioimmunoassays to measure circulating ET-1 and ET-3 levels in normotensive and different hypertensive rat models so that the role of endothelin in the regulation of vasomotor function can be studied. We also assessed the stimulatory effects of endotoxin on plasma and liver lymph ET-1 and ET-3 levels. The circulating ET-1 levels in normotensive rats, SHRs, and DOCA-salt hypertensive rats were 2.3 +/- 0.5, 2.1 +/- 0.4, and 2.1 +/- 0.9 pg/ml, respectively. Similarly, the plasma ET-3 levels in normotensive and different hypertensive rats were similar, ranging from 19.7 +/- 1.5 to 24.7 +/- 2.2 pg/ml. The data indicate that steady-state circulating levels of endothelins are a poor correlate of the hypertensive state. Endotoxin (30 mg/kg i.v. over 15 min) reduced blood pressure significantly and augmented plasma ET-1 levels by sevenfold (29.1 +/- 3.7 vs. 4.1 +/- 0.6 pg/ml in the vehicle group; p less than 0.05) and ET-3 levels by twofold (47.7 +/- 7.0 vs. 22.7 +/- 4.0 pg/ml in the vehicle group; p less than 0.05). Human TNF-alpha (30 ng/kg/min x 30 min), a putative mediator of endotoxin shock, enhanced plasma ET-1 (18.3 +/- 1.0 vs. 2.7 +/- 0.4 pg/ml in the vehicle group; p less than 0.05) by sevenfold and ET-3 levels by twofold (45.7 +/- 2.0 vs. 27.1 +/- 4.0 pg/ml in the vehicle group; p less than 0.05) without affecting blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)