Factor V Leiden mutation: an unrecognized cause of hemiplegic cerebral palsy, neonatal stroke, and placental thrombosis

Activated protein C resistance caused by an Arg506Gln mutation in the factor V gene (factor V Leiden mutation) is the most common cause of familial thrombosis. This mutation is associated with arterial and venous thromboembolic disease in neonates, infants, and children, but is not a significant risk factor for ischemic stroke in adults. We report on 3 babies with different neonatal cerebrovascular disorders including ischemic infarction and hemorrhagic stroke who are heterozygous for factor V Leiden mutation. One infant had multiple thrombi in the fetal placental vasculature. This is the first reported association between hemiplegic cerebral palsy, placental thrombosis, and factor V Leiden mutation. We suspect that activated protein C resistance may be an important cause of in utero cerebrovascular disease and hemiplegic cerebral palsy.

Random dot stereoacuity of preschool children. ALSPAC "Children in Focus" Study Team

PURPOSE

Commercially available book-format random dot stereopsis tests for children are quick and simple to use, but provide accurate measurement of stereoacuity only in children age 5 years or older. Alternative methods for preschool children provide only pass/fail information or require lengthy laboratory-based protocols. To address the need for a quick and accurate measure of random dot stereoacuity in the preschool age range, we developed a new book-format random dot stereoacuity test.

METHODS AND RESULTS

A total of 25 potential shapes for the new test were evaluated in a group of 43 healthy full-term children aged 3 years +/- 2 months. Eleven shapes that were identified successfully by more than 95% of the 3-year-olds were selected to be incorporated into the preschool stereotest. The preschool random dot stereotest books were administered to more than 1000 normal children and pediatric patients in multiple settings: a research laboratory (Retina Foundation SW), a population screening project (University of Bristol, UK), eye clinics (Children's Medical Center, Dallas, Tex), and a day care center (Federal University, São Paulo, Brazil). Randot, Lang 1, Frisby, or Titmus stereoacuity tests also were administered. Orthoptic or ophthalmic examinations were obtained for all children as a gold standard. Outcome measures were success rate and concordance with the clinical examination. Sensitivity, specificity, and accuracy exceeded 0.90 both in clinical and screening settings.

CONCLUSIONS

The preschool random dot books had a higher success rate than other tests in the preschool age range and provided accurate measurement of stereoacuity in the 3- to 5-year-old age range.

Standardizing laparoscopic procedure time and determining the effect of patient age/gender and presence or absence of surgical residents during operation. A prospective multicenter trial

BACKGROUND

Most of the expense of laparoscopic cholecystectomy (LC) is incurred while the patient is in the operating room (OR). Half of this operating room cost is equipment and the other half is personnel. What is an acceptable LC procedure time and how much variation is there? What are the effects of age, gender, and expertise on the mean LC procedure time?

METHODS

A prospective, multicenter gathering of LC procedure times and task component times was performed through the cooperative effort of members of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES) at 11 hospitals. The effect of LC time of age, gender, and surgical resident was recorded.

RESULTS

The mean LC time for 359 cases was 73 +/- 28 min. The percent of this LC time for the following component tasks included: to place and remove trocars, 34%; total dissection time, 40%; intraoperative cholangiogram, 15%; and removing the gallbladder, 7%. Age and gender did not change LC time, but the presence of a surgical resident prolonged LC time from 53 to 79 min due to an increase in all LC component task times.

CONCLUSIONS

LC time was globally calibrated in 11 North American hospitals and was found to be affected by expertise but not by gender or age. The mean and standard deviation of LC time can be used for purposes of self-assessing quality performance.

A process-oriented reasoner about physiology

This paper presents the RAP system: a reasoner about physiology. RAP performs two tasks: (1) it infers the behaviour of a complex physiological process using the behaviours of its subprocesses and the relationships between them; (2) it reasons about the effect of introducing a fault into the model. In order to reason about the behaviour of a complex process, RAP uses a mechanism which: (i) represents how subprocesses behave; (ii) establishes how these subprocesses affect each others behaviors; (iii) 'aggregates' these behaviors together to obtain the behavior of the top level process; (iv) gives that process a temporal context in which to act. RAP uses limited common sense knowledge about faults to reason about their effect in terms of the generation of new processes and the misbehavior of existing ones. The effects are then propagated throughout the model to obtain the overall effect of the fault.

National Reactive Phosphate Rock Project —aims, experimental approach and site characteristics

Summary. Field-based cutting trials, which formed part of the National Reactive Phosphate Rock Project, were established across Australia in a range of environments to evaluate the agronomic effectiveness of 5 phosphate rocks, and 1 partially acidulated phosphate rock, relative to either single superphosphate or triple superphosphate. The phosphate rocks differed in reactivity. Sechura (Bayovar) and North Carolina phosphate rocks were highly reactive (>70% solubility in 2% formic acid), whilst Khouribja (Moroccan) and Hamrawein (Egypt) phosphate rock were moderately reactive. Duchess phosphate rock from Queensland was relatively unreactive (<45% solubility in 2% formic acid). Phosphate rock effectiveness was assessed by measuring pasture production over a range of phosphorus levels, and by monitoring bicarbonate-soluble phosphorus extracted from soil samples collected before the start of each growing season. Other treatments included single large applications of triple superphosphate, partially acidulated phosphate rock and North Carolina phosphate rock applied at 2 rates, and the application of monocalcium phosphate and North Carolina phosphate rock sources without sulfur to evaluate the importance of sulfur in the potential use of phosphate rock fertilisers at each site. A broad range of environments were represented over the 30 sites which were based on pastures using annual and/or perennial legumes and perennial grasses. Rainfall across the network of sites ranged from 560 to 4320 mm, soil pH (CaCl2) from 4.0 to 5.1, and Colwell-extractable phosphorus ranged from 3 to 47 µg/g before fertiliser application. Two core experiments were established at each site. The first measured the effects of phosphate rock reactivity on agronomic effectiveness, while the second measured the effects of the degree of water solubility of the phosphorus source on agronomic effectiveness. The National Reactive Phosphate Rock Project trials gave the opportunity to confirm the suitability of accepted procedures to model fertiliser response and to develop new approaches for comparing different fertiliser responses. The Project also provided the framework for subsidiary studies such as the effect of fertiliser source on soil phosphorus extractability, cadmium and fluorine concentrations in herbage, evaluation of soil phosphorus tests, and the influence of particle size on phosphate rock effectiveness. The National Reactive Phosphate Rock Project presents a valuable model for a large, Australia-wide, collaborative team approach to an important agricultural issue. The use of standard and consistent experimental methodologies at every site ensured that maximum benefit was obtained from data generated. The aims, rationale and methods used for the experiments across the network are presented and discussed.

Inherited resistance to HIV-1 conferred by an inactivating mutation in CC chemokine receptor 5: studies in populations with contrasting clinical phenotypes, defined racial background, and quantified risk

BACKGROUND

CC chemokine receptor 5 (CCR5) is a cell entry cofactor for macrophage-tropic isolates of human immunodeficiency virus-1 (HIV-1). Recently, an inactive CCR5 allele (designated here as CCR5-2) was identified that confers resistance to HIV-1 infection in homozygotes and slows the rate of progression to AIDS in heterozygotes. The reports conflict on the effect of heterozygous CCR5-2 on HIV-1 susceptibility, and race and risk levels have not yet been fully analyzed. Here we report our independent identification of CCR5-2 and test its effects on HIV-1 pathogenesis in individuals with contrasting clinical outcomes, defined race, and quantified risk.

MATERIALS AND METHODS

Mutant CCR5 alleles were sought by directed heteroduplex analysis of genomic DNA from random blood donors. Genotypic frequencies were then determined in (1) random blood donors from North America, Asia, and Africa; (2) HIV-1+ individuals; and (3) highly exposed-seronegative homosexuals with quantified risk.

RESULTS

CCR5-2 was the only mutant allele found. It was common in Caucasians, less common in other North American racial groups, and not detected in West Africans or Tamil Indians. Homozygous CCR5-2 frequencies differed reciprocally in highly exposed-seronegative (4.5%, n = 111) and HIV-1-seropositive (0%, n = 614) Caucasians relative to Caucasian random blood donors (0.8%, n = 387). This difference was highly significant (p < 0.0001). By contrast, heterozygous CCR5-2 frequencies did not differ significantly in the same three groups (21.6, 22.6, and 21.7%, respectively). A 55% increase in the frequency of heterozygous CCR5-2 was observed in both of two cohorts of Caucasian homosexual male, long-term nonprogressors compared with other HIV-1+ Caucasian homosexuals (p = 0.006) and compared with Caucasian random blood donors. Moreover, Kaplan-Meier estimates indicated that CCR5-2 heterozygous seroconvertors had a 52.6% lower risk of developing AIDS than homozygous wild-type seroconvertors.

CONCLUSIONS

The data suggest that homozygous CCR5-2 is an HIV-1 resistance factor in Caucasians with complete penetrance, and that heterozygous CCR5-2 slows the rate of disease progression in infected Caucasian homosexuals. Since the majority (approximately 96%) of highly exposed-seronegative individuals tested are not homozygous for CCR5-2, other resistance factors must exist. Since CCR5-2 homozygotes have no obvious clinical problems, CCR5 may be a good target for the development of novel antiretroviral therapy.

Effects of phosphate rock products on soil pH

Summary. Changes to soil pH (CaCl2 ) following annual applications of phosphate rock (PR) and water-soluble phosphorus products were investigated in the National Reactive Phosphate Rock Project. It was difficult to measure small changes in pH due to variation in pH within each site and across years. pH (the change over time from the initial soil pH at that plot) was significantly influenced by fertiliser product at 13 of the 27 sites examined. At 5 sites, one or more of the PR products had pH of 0.07–0.21 units greater than the pH of the control. At the other 8 sites, the pH of the control plot was greater than or equal to the that of the PR plots, or significant increases in pH occurred in the single superphosphate plots. The changes in soil pH following application of the fertiliser products were inconsistent both within and between sites. Chemically the PR products have the potential to reduce the rate of acidification in soils where the products dissolve readily, however, this was not generally reflected in the field, where the application of PR products only increased soil pH at a limited number of sites.

Coordinating a large multicentered HIV research project

Coordinating a large multicentered pediatric HIV clinical research study is particularly challenging for nurses. The cohort of patients and their families face multiple stressors, which make recruitment and compliance difficult. Additionally, when many departments within the institution are involved, coordination is often problematic. Ethical issues sometimes arise. Nurses must find ways to adapt what they learn from the study to their nursing practice. The nurse coordinators of the Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted HIV (P2C2HIV) study discuss the unique challenges of such a project and the various strategies for successful completion.

Inotropic agents in the critically ill

Inotropic agents are commonly used in critically ill patients. This heterogeneous group of drugs are potentially hazardous if used without a good understanding of cardiovascular physiology and pathophysiology and without due attention to some general principles for their use. We suggest guidelines for the administration of these agents in all clinical settings.

Disappearing subdural hematomas in children

Subdural hematomas in infants and young children are uncommon, usually occurring from nonaccidental trauma in infants or from trauma associated with motor vehicles. We report 4 children with apparent unilateral convexity subdural hematomas, 3 of which occurred from household falls and 1 occurring from a fall out of a window. These injuries were characterized by clinical symptoms consistent with the apparent forces involved, which were relatively minor in the first three instances. The clots resolved spontaneously within the first 1-2 days after injury. Such collections are likely located at least partly within the subarachnoid space, but may mimic more clinically significant subdural hematomas. Their recognition may influence decisions regarding both surgical evacuation and the likelihood of nonaccidental injury. Clinical and radiographic features distinguishing these 'disappearing subdurals' from more typical subdural hematomas are discussed.

Systematic literature review: outcome measures for child and adolescent mental health services

BACKGROUND

Outcome measurement is an important component of health care service evaluation. The aim of this paper is to review child and adolescent mental health outcome measures and identify outcome measurement tools for use in routine clinical practice.

METHOD

A systematic literature review was undertaken, using Medline and Psych Info and supplemented by correspondence with relevant institutions and authorities in the field. The review identifies potential specific outcome measurement tools. These tools are evaluated using the scientific criteria of validity and reliability, responsiveness to change, and appropriateness of each tool's format for use in routine clinical practice.

RESULTS

Three broad categories of outcome are identified: population outcomes, specific outcome and performance indicators. Nineteen specific outcome measurement tools are short-listed and compared in detail. No single tool is suitable for use as a comprehensive outcome measurement tool in routine clinical practice.

CONCLUSION

A combination of some of the tools short-listed will cover all the necessary outcome items. However, the increase in assessment time will reduce clinical usefulness. Further research is needed to modify or created appropriate outcome measurement tools for use in routine clinical practice.

Crosstalk between the thyroid hormone and peroxisome proliferator-activated receptors in regulating peroxisome proliferator-responsive genes

Peroxisome proliferators and thyroid hormones have overlapping metabolic effects and regulate a similar subset of genes involved in maintaining lipid homeostasis. Transcriptional activation by peroxisome proliferators is mediated by peroxisome proliferator-activated receptors (PPARs) that bind to specific peroxisome proliferator-response elements (PPREs) through heterodimerization with retinoid X receptors (RXRs). We examined the effect of thyroid hormone receptor alpha (TR alpha) on DNA binding in vitro and transcriptional activation in vivo by rat PPAR. Gel mobility shift assays using in vitro translated receptors demonstrated that TR alpha was capable of binding on its own and cooperatively with RXR alpha to the rat acyl-CoA oxidase PPRE and of inhibiting the binding of rat PPAR/RXR alpha heterodimers to this element. This inhibition was the result of competition between TR alpha and PPAR for limiting amounts of the heterodimerization partner RXR alpha and for binding to the PPRE. Interestingly, cotransfection of a TR alpha expression plasmid into mammalian cells resulted in potentiation of the peroxisome proliferator- and PPAR/RXR alpha-dependent transcriptional induction of a reporter gene containing the acyl-CoA oxidase PPRE. TR alpha therefore appears to cooperate with RXR and PPAR to positively modulate peroxisome proliferator-dependent transactivation in vivo. Our findings suggest that there is crosstalk between the thyroid hormone and peroxisome proliferator signaling pathways in the regulation of peroxisome proliferator-responsive genes.

What happens to patients awaiting arthritis surgery?

The length of orthopaedic waiting lists attracts much interest, but the needs of patients awaiting surgery gain little attention. We studied 97 patients awaiting lower-limb surgery (49 osteoarthritis, 41 rheumatoid arthritis, seven other diagnoses). Ninety had pain; 44 significant night pain. Psychological and social problems were common (44 and 45 cases respectively). Only 11 were employed full-time. Sixty-eight required help with daily activities, usually from relatives and neighbours. Forty-three patients walked less than 120 metres in 12 minutes. After review we recommended further aids in 32, medication changes in 27, and additional professional support in six cases. Clinical changes whilst on the waiting list caused alterations in the priority for surgery in 32 cases; the planned procedure was no longer appropriate in 12 of these. We suggest that patients awaiting surgery require clinical review to maintain quality of life; and that waiting lists require administrative review so that patients in need of surgery receive it as soon as possible.

Frontonasal malformation and cloacal exstrophy: a previously unreported association

We report on a child with frontonasal malformation (FNM) and cloacal exstrophy, a combination of findings that have not been reported previously. In FNM and cloacal exstrophy, associated malformations are rare. FNM and cloacal exstrophy both represent abnormalities of the development of the midline field; this combination of anomalies in this patient suggests an impairment of caudal and cranial midline development during blastogenesis.

An experimental study of the effects of craniofacial growth on the long-term positional stability of microfixation

Recent clinical reports have documented a potential problem associated with the use of microfixation in the growing craniofacial skeleton, i.e., the finding of microplates and microscrews within the endocranial cavity during repeat surgery. This animal experiment using Yorkshire pigs was designed to determine if this type of passive internal displacement could be demonstrated in an animal model, the frequency of internal displacement, and the potential consequence of such events from a neurohistological standpoint. Ten female Yorkshire piglets underwent left unilateral fronto-orbital advancement at age 3 weeks, fixation being achieved with microplates and screws. The position of the hardware was determined by direct inspection, after they were killed at 6 months of age (skeletal maturity). Ten microplates (28%) showed complete intracranial translocation, whereas nine (27%) remained on the ectocranial surface. The majority, 16 (44%), were between the outer and inner cortices of the calvaria. Gross examination of the brain tissue underlying the translocated hardware showed indentation "pits" forming as a result of such translocation. Histological examination of the cerebrum and meninges of these pits revealed loss of the most superficial connecting cell layer, with focal neuronal distortion. The leptomeninges were intact and there was no cerebritis, gliosis, or hypoxic change. These findings confirm that in this pig model microfixation hardware will undergo passive intracranial ranial translocation and that there are demonstrable histological alterations in the underlying brain and meninges. The long-term effects of these observed anatomical changes are unknown.

Community attitudes on the family of issues surrounding the death of terminal patients

In two studies, respondents made recommendations for the medical treatment of a terminally ill elderly woman. The woman was or was not experiencing intractable pain, and had requested either heroic medical efforts or euthanasia. Respondents' recommendations were influenced by both the specific wishes of the patient and the pain the person was experiencing. However, participants were not completely swayed by the patient's wishes: only about half of the sample recommended euthanasia even when the patient was in intractable pain and had requested death; also, many subjects would not resuscitate the patient whose heart or lungs failed, even though she had requested heroic measures. Respondent attitudes toward euthanasia predicted recommendations in the expected directions. We suggest that there is less dissent on the issues that arise for medical treatments at the end of life than has been widely assumed.