Assessment of directional Doppler ultrasound techniques in the diagnosis of carotid artery diseases.

Three diagnostic techniques based on the use of directional doppler ultrasound have been evaluated in comparison with direct percutaneous carotid angiography and arch aortography. The results indicate that the non-invasive techniques provide a safe, atraumatic method of assessing patients with symptoms of extracranial occlusive arterial disease.     

Fructose load test—anin vivo screening test designed to assess pyruvate dehydrogenase activity and interconversion

Anin vivo screening test is described, which is designed to assess the activity and interconversion of the human pyruvate dehydrogenase complex. Oral fructose was administered to six healthy subjects following (a) an overnight fast and (b) an oral glucose load. The rise in blood pyruvate and lactate levels following fructose was almost twice as great in the fasted state compared to the fed (post-glucose) state. It is proposed that this difference is due to the conversion of pyruvate dehydrogenase to its active form, following feeding.     

Factors associated with different hygiene practices in the homes of 15 month old infants

Background: Developmental dyslexia is a neurodevelopmental learning disability characterised by unexpectedly poor reading and unknown aetiology. One hypothesis proposes excessive platelet activating factor, a potent vasodilator, as a contributor, implying that there should be a negative association between dyslexia and high blood pressure (HBP). Since both conditions have a partial genetic basis, this association may be apparent at the familial level. Aims: To test this prediction in dyslexic and non-dyslexic children. Methods: Individuals and families with (HBP+) and without (HBP-) a family history of HBP were compared. Results: Proportionately fewer dyslexics (49/112) than controls (11/12) were HBP+. Families with multiple, all dyslexic children were less likely to be HBP+ (7/16) than those with a non-dyslexic child (11/11). Within families, mean child scores on reading were higher in the HBP+ group (mean 44.3, SE 0.95) than in the HBP- group (mean 40.3, SE 0.87). Conclusion: HBP+ family history is associated with better performance on reading. The prediction of a negative association between dyslexic status and familial high blood pressure is therefore confirmed.     

The measurement and prevention of erosion and abrasion

OBJECTIVES: To develop a reproducible method to measure tooth wear and assess the protection given by dentine bonding agents in an erosive/abrasive wear regime. METHODS: Seal and Protect (Dentsply, UK) and Optibond Solo (Kerr, UK) were each applied to 20 extracted teeth and subjected to 3000 cycles in a reciprocating erosion/abrasion wear machine. A further 20 teeth, without protection, were subjected to the same wear regime and were either brushed in water or immersed in acid. Impressions were taken by a standardised technique and were scanned with a non-contacting laser profilometer. The amount of erosion was measured at the same co-ordinates before and after erosion using 2mm diameter metal discs as reference points. RESULTS: The amount of wear on Seal and Protect had a mean 24.8 microm (SD 57.4 microm) and for Solo it was 1.4 microm (24.5 microm), and this difference was statistically significant (p=0.02). There was no statistically significant difference in the wear measured on the teeth brushed in water or immersed in acid. The wear measured on the unprotected teeth was 243 microm (SD 120 microm) and was statistically significantly different to the protected surfaces (p=0.001). CONCLUSION: Both Seal and Protect and Solo protected the teeth in this wear regime and the technique could be used clinically for patients with uncontrolled dental erosion.     

Preventing postnatal growth failure--the significance of feeding when the preterm infant is clinically stable

Nutrition guidelines and growth targets for preterm infants are currently based upon the reference standard of intrauterine growth and fetal nutrient accretion rates. This may not be an entirely appropriate standard--it is rarely achieved in clinical practice. Postnatal growth failure of very preterm infants is a universal problem with potentially significant, adverse neurological and health outcomes. The nutrient deficit that accumulates in the early weeks postdelivery when the preterm infant is clinically unstable is difficult to recover. Weight, length and head circumference measurements remain important clinical indicators of growth but composition of weight gain is emerging as a necessary measure in determining the adequacy of nutrition intake and growth. Recommended protein and energy intakes for very preterm infants are difficult to achieve with commercial human milk fortifiers and during hospitalisation, targeting the fortification of human milk to optimise the protein to energy ratio of milk feeds is necessary to ensure appropriate composition of weight gain. Postdischarge, continued fortification of human milk feeds may be required for a limited period of time for preterm infants with suboptimal weight for corrected age. AIM AND METHODS: The following systematic review is aimed to derive evidence-based best practice guidelines for prevention of postnatal growth failure of very preterm infants who are clinically stable and growing. The focus is on reviewing the standard upon which ideal growth and nutrition guidelines are based and targeting fortification to maximise the protein to energy ratio in human milk feeds to ensure appropriate composition of weight gain. Directions for future research are provided. For the literature review the data bases Medline, EMBASE, CINAHL, the Cochrane Library and reference lists of review articles were reviewed to December 2006. A hand search of paediatric and perinatal journals was also conducted.     

Soft tissue morphology of the naso-maxillary complex following surgical correction of maxillary hypoplasia

Orthognathic surgery is undergone to improve facial and dental aesthetics and to improve function. Three dimensional (3D) soft tissue analysis based on stereophotogrammetry provides a realistic measurement of facial morphology. There is a need for objective assessment of surgery outcomes. The study aim was to evaluate the 3D naso-maxillary complex soft tissue morphology following Le Fort I maxillary advancement and compare the findings with a local reference group. 3D images of 112 volunteers were captured using stereophotogrammetry and viewed by 8 lay people; 40 images (16 males and 24 females) were chosen as the reference group to have harmonious facial appearance. The linear and angular measurements of this group were compared with 35 patients (19 female and 16 male) who had maxillary advancement in the post-surgical group. Facial morphology post-surgery was similar to the reference group, except the nasal base width which was wider by 2.3mm in males and 2.6mm in females. In the orthognathic group, the females had a smaller nasolabial angle by 9.7° than the reference group. In conclusion, 3D imaging is a sensitive tool for analysing facial appearance. Compared with a control group, statistical differences were identified in soft tissue morphology which should be considered in surgical planning and patient consent.     

Salivary antimicrobial proteins associate with age‐related changes in streptococcal composition in dental plaque

Secretion of antimicrobial proteins (AMPs) and salivary antibodies can modify biofilm formation at host body surfaces. In adolescents, associations have been reported between dental caries and salivary AMPs. AMPs demonstrate direct antimicrobial effects at high concentrations, and at lower more physiological concentrations they mediate changes in host cell defenses, which may alter the local environment and indirectly shape local biofilm formation. The expression of salivary AMPs in preschool children, at an age when the oral bacteria are known to change, has not been investigated. We sought to investigate salivary AMP expression in the context of previously well‐documented changes in the oral cavities of this age group including salivary immunoglobulin A (IgA), oral bacteria and dental caries. Dental plaque and saliva were collected from 57 children aged 12–24 months at baseline, of whom 23 children were followed‐up at 3 years of age. At each time, saliva was assessed for LL37, human neutrophil peptides 1–3, calprotectin, lactoferrin, salivary IgA, total plaque bacteria and Streptococcus mutans. Over time, concentrations of AMPs, S. mutans and bacteria‐specific salivary IgA increased. Caries experience was also recorded when children were 3 years old. Concentrations of AMPs were highest in the saliva of 3‐year‐old children with the greatest burden of S. mutans. These data suggest that salivary AMPs are variable over time and between individuals, and are linked with bacterial colonization. At follow up, the majority of children remained caries free. Larger longitudinal studies are required to confirm whether salivary AMP levels are predictive of caries and whether their modulation offers therapeutic benefit.     

Cerebral white matter damage in HIV infection demonstrated using β-amyloid precursor protein immunoreactivity

We have examined brain sections from 55 autopsy cases of AIDS for the prevalence and severity of axonal damage, assessed using β-amyloid precursor protein (βAPP) immunoreactivity as a marker of such damage. The cases were subdivided into cases with HIV encephalitis with multinucleated giant cells (MGC), cases with other specific pathology, such as cerebral toxoplasmosis or lymphoma, cases with non-specific pathology and cases with no pathology. Significantly more foci containing βAPP⁺ axons were found in cases with HIV encephalitis with MGC (80%) and in cases with other specific pathology (58%) than in those with non-specific (30%) or no pathology (30%). The prevalence and abundance of βAPP⁺ axons generally paralleled the severity of pallor of myelin staining of cerebral white matter in cases without other specific pathology but in 4 cases without any pallor of myelin staining βAPP⁺ axons were present, suggesting that it may be a more sensitive marker of some forms of white matter damage in HIV infection than myelin pallor. Foci of βAPP⁺ axons were found in subcortical and deep white matter but did not convincingly co-localise with foci of demonstrable HIV infection as indicated by the presence of MGC and HIV p24 immunoreactivity. In contrast, they showed an approximately perivascular distribution at some sites in all of the disease categories studied. We consider this localisation to be more suggestive of a vascular pathogenetic mechanism of deep white matter damage in HIV infection than a mechanism dependent on diffusion of local myelinotoxic products from foci of cerebral HIV infection. Received: 11 March 1996 / Revised: 31 July 1996 / Accepted: 10 September 1996     

The diagnostic significance of serological screening of patients with uveitis

A prospective clinical and serological study was carried out in 165 consecutive patients with anterior uveitis (AU), and a control group comprising 110 healthy volunteers, and 70 patients with Behcet's disease. It appeared from our analysis that infections such as syphilis and brucellosis should be suspected in non-responsive cases of anterior uveitis. Furthermore, a highly significant frequency (41%) of sero-positive herpes simplex virus (HSV) antibodies in patients with AU would suggest a possible role of this virus in the etiology of anterior uveitis. Hence, specific treatment in cases of presumptive intraocular infections would lead to marked clinical improvement in terms of intensity and duration of the eye inflammatory process.     

Organisation of the visceral solitary tract nucleus in the ferret as defined by the distribution of choline acetyltransferase and nerve growth factor receptor immunoreactivity

The cholinergic innervation of the visceral component of the nucleus of the solitary tract in the ferret was investigated by using choline acetyltransferase immunocytochemistry. The subdivisions of the ferret solitary tract nucleus as defined by Nissl architectonics were found to correspond to most of those previously assigned to the cat solitary tract nucleus. The subnuclei of the ferret solitary tract nucleus were also outlined by using immunohistochemical and histochemical methods to stain for nerve growth factor (NGF) receptor and acetylcholinesterase, respectively. In particular, the gelatinosus and interstitial subnuclei stain intensely for NGF receptor immunoreactivity and for acetylcholinesterase activity. Since abundant NGF receptor immunoreactivity is observed also in the nodose ganglion and in the solitary tract, it was assumed that the gelatinosus and the interstitial subnuclei represent the principal sites of termination of primary visceral afferents. A rich choline acetyltransferase-positive terminal axonal arborization was located in all of the subdivisions of the solitary tract nucleus but was found to be lacking in the gelatinosus and interstitial subnuclei. A small number of giant choline acetyltransferase-positive axon terminals was seen in the subnucleus gelatinosus but was assumed to be of doubtful functional significance because these terminals derive from only one or two large axons on each side of the brain. The weak cholinergic innervation of the gelatinosus and interstitial subnuclei and the stronger innervation of the other subnuclei suggest that acetylcholine has a more important role in the secondary rather than the primary processing of afferent visceral information. Because the distribution of acetylcholinesterase activity in the nucleus of the solitary tract matches that of the NGF receptor immunoreactivity rather than that of the cholinergic acetyltransferase immunoreactivity, a non-cholinergic function for acetylcholinesterase may dominate in the solitary tract nucleus of the ferret.