PubMed Health⌕ Search

Biomedical subjects

H E Hughes

Publications and source records attributed to H E Hughes.

At least 19 recordsLinked to original sources
PubMed2006

Real-time epidemic forecasting for pandemic influenza.

The ongoing worldwide spread of the H5N1 influenza virus in birds has increased concerns of a new human influenza pandemic and a number of surveillance initiatives are planned, or are in place, to monitor the impact of a pandemic in near real-time. Using epidemiological data collected during the early stages of an outbreak, we show how the timing of the maximum prevalence of the pandemic wave, along with its amplitude and duration, might be predicted by fitting a mass-action epidemic model to the surveillance data by standard regression analysis. This method is validated by applying the model to routine data collected in the United Kingdom during the different waves of the previous three pandemics. The success of the method in forecasting historical prevalence suggests that such outbreaks conform reasonably well to the theoretical model, a factor which may be exploited in a future pandemic to update ongoing planning and response.

Disease Outbreaks↗
PubMed2005

Partial NSD1 deletions cause 5% of Sotos syndrome and are readily identifiable by multiplex ligation dependent probe amplification.

BACKGROUND: Most cases of Sotos syndrome are caused by intragenic NSD1 mutations or 5q35 microdeletions. It is uncertain whether allelic or genetic heterogeneity underlies the residual cases and it has been proposed that other mechanisms, such as 11p15 defects, might be responsible for Sotos cases without NSD1 mutations or 5q35 microdeletions. OBJECTIVE: To develop a multiplex ligation dependent probe amplification (MLPA) assay to screen NSD1 for exonic deletions/duplications. METHODS: Analysis was undertaken of 18 classic Sotos syndrome cases in which NSD1 mutations and 5q35 microdeletions were excluded. Long range polymerase chain reaction (PCR) was used to characterise the mechanism of generation of the partial NSD1 deletions. RESULTS: Eight unique partial NSD1 deletions were identified: exons 1-2 (n = 4), exons 3-5, exons 9-13, exons 19-21, and exon 22. Using long range PCR six of the deletions were confirmed and the precise breakpoints in five cases characterised. This showed that three had arisen through Alu-Alu recombination and two from non-homologous end joining. CONCLUSIONS: MLPA is a robust, inexpensive, simple technique that reliably detects both 5q35 microdeletions and partial NSD1 deletions that together account for approximately 15% of Sotos syndrome.

Base Sequence↗
PubMed2004

Maternal uniparental disomy 16 and genetic counseling: new case and survey of published cases.

Uniparental disomy (UPD) is the occurrence of both homologous chromosomes from one parent. Maternal UPD(16) is the most often reported UPD other than UPD(15); almost all cases are associated with confined placental mosaicism (CPM). Most of maternal UPD(16) cases are characterised by intrauterine growth retardation (IUGR) and different congenital malformations. Maternal UPD(16) has therefore been suspected to have clinical effects: however, the lack of uniqueness and specificity of the birth defects observed suggests that the phenotype may be related in parts to placental insufficiency. We report on a new case of maternal UPD(16) associated with low level trisomy 16 mosaicism in placenta and fetus. IUGR was noticed at 19 gestational weeks and the fetus died intrauterine. Apart from different craniofacial dysmorphisms she showed anal atresia. While IUGR is probably associated with trisomy 16 mosaicism, anal atresia is more characteristic for maternal UPD( 16). Considering the features in our patient as well as those in maternal UPD (16) cases from the literature, indications for UPD (16) testing can be defined: They include trisomy 16 mosaicism, IUGR and congenital anomalies (anal atresia, congenital heart defects). However, there is an overlap of clinical signs in mosaic trisomy 16 cases mosaic for maternal UPD(16) as opposed to those mosaic for biparental disomy 16. The management of trisomy 16 pregnancies should not differ from those in which maternal UPD(16) is confirmed. Therefore, a prenatal testing for UPD(16) is not useful, but it should be offered postnatally. The molecular genetic proof of maternal UPD(16) excludes an increased recurrence risk for the family for further pregnancies.

Adult↗
PubMed1999

Two components of actin-based retrograde flow in sea urchin coelomocytes.

Sea urchin coelomocytes represent an excellent experimental model system for studying retrograde flow. Their extreme flatness allows for excellent microscopic visualization. Their discoid shape provides a radially symmetric geometry, which simplifies analysis of the flow pattern. Finally, the nonmotile nature of the cells allows for the retrograde flow to be analyzed in the absence of cell translocation. In this study we have begun an analysis of the retrograde flow mechanism by characterizing its kinetic and structural properties. The supramolecular organization of actin and myosin II was investigated using light and electron microscopic methods. Light microscopic immunolocalization was performed with anti-actin and anti-sea urchin egg myosin II antibodies, whereas transmission electron microscopy was performed on platinum replicas of critical point-dried and rotary-shadowed cytoskeletons. Coelomocytes contain a dense cortical actin network, which feeds into an extensive array of radial bundles in the interior. These actin bundles terminate in a perinuclear region, which contains a ring of myosin II bipolar minifilaments. Retrograde flow was arrested either by interfering with actin polymerization or by inhibiting myosin II function, but the pathway by which the flow was blocked was different for the two kinds of inhibitory treatments. Inhibition of actin polymerization with cytochalasin D caused the actin cytoskeleton to separate from the cell margin and undergo a finite retrograde retraction. In contrast, inhibition of myosin II function either with the wide-spectrum protein kinase inhibitor staurosporine or the myosin light chain kinase-specific inhibitor KT5926 stopped flow in the cell center, whereas normal retrograde flow continued at the cell periphery. These differential results suggest that the mechanism of retrograde flow has two, spatially segregated components. We propose a "push-pull" mechanism in which actin polymerization drives flow at the cell periphery, whereas myosin II provides the tension on the actin cytoskeleton necessary for flow in the cell interior.

Actins↗
PubMed1998

Severe prenatal growth retardation, dysmorphic features, pigmentary retinopathy, and generalized absence of subcutaneous tissues: a new entity?

We report a girl with severe prenatal and postnatal growth retardation, congenital generalized absence of subcutaneous tissue, and facial and somatic changes with some similarities to Wiedemann-Rautenstrauch syndrome (WRS). However, the patient's condition is sufficiently different from those reported previously to suggest that this patient represents a new syndrome. The abnormalities observed in this patient overlap with those of WRS, Cockayne syndrome, type A (CSA), and osteodysplastic primordial dwarfism type III (OPD III), but also include choanal atresia and pigmentary retinopathy.

Abnormalities, Multiple↗
PubMed1998

Contracting for clinical genetic services: the Welsh model.

In a time of increasing competition for clinical services resources, it is imperative that health professionals actively participate in the commissioning process in order to ensure that established clinical standards are not compromised. Introduction of the NHS reforms in the UK in the early 1990s highlighted the difficulties in contracting for a specialised service such as clinical genetics, especially in the absence of a consensus regarding the contract currency. An average block contract price for each new family referred was introduced in Wales in 1992, and data from the subsequent five years show that this charging system is economically feasible and has the advantages of (1) recognising the contribution to care of non-medical personnel on the genetics team, (2) covering follow up including the counselling of relatives, (3) protecting the service from loss of income owing to non-attendance, and (4) providing a basis for negotiation when new services are being proposed to purchasers. Activity data show that while the majority of conditions incur below average cost, the mean cost is influenced by a small number of autosomal dominant and X linked disorders. The cost risk to the provider for seeing families over an extended period is minimal, as the data establish that family files experience an exponential decrease in activation probability over the early years, but this becomes constant later on. The robustness of the system is dependent on accurate baseline data on referral patterns to the service, recording of activity, and staff costs.

Contract Services↗
PubMed1997

Lateral meningocele syndrome: three new patients and review of the literature.

One female and two male patients with multiple lateral meningoceles are presented. They do not have neurofibromatosis or Marfan syndrome and share findings with the two previously described patients with multiple lateral meningoceles. The original report by Lehman et al. [1977: J Pediatr 90:49-54] was titled "familial osteosclerosis," because osteosclerosis was present in the proposita and her mother; the patient described by Philip et al. [1995: Clin Dysmorphol 4:347-351] also had increased bone density of the skull base and the sutures. Thickened calvaria were present in one of our patients; two had a prominent metopic suture. Other shared findings include multiple lateral meningoceles, Wormian bones, malar hypoplasia, downslanted palpebral fissures, a high narrow palate, and cryptorchidism in males. In addition, our patients showed ligamentous laxity, keloid formation, hypotonia, and developmental delay. A short umbilical cord was noted in two patients. One had a hypoplastic posterior arch of the atlas and an enlarged sella, as reported by Lehman et al. [1977]. Our patients appear to have the same syndrome as previously reported. We suggest it be called "lateral meningocele syndrome," because of this unique finding.

Abnormalities, Multiple↗
PubMed1996

Prenatal cocaine exposure affects the acoustic startle response in adult rat.

This study investigated whether prenatal exposure to cocaine alters reflux excitability in adulthood. Pregnant rats received 30 or 60 mg/kg/day cocaine HCl i.g. during gestational days 8-22. Vehicle-treated control rats were pair-fed/watered to rats receiving 60 mg/kg cocaine. A non-treated control group was also maintained. At parturition, litters from all four groups were surrogate fostered and then weaned at 21 days of age. In adulthood, rats were tested in an acoustic startle response (ASR) apparatus for 120 trials using a 116 dB signal on 2 consecutive days. On Day 2, subjects received a single injection of d-amphetamine sulfate s.c. (1.0 mg/kg) just prior to testing. ASR amplitude and latency were recorded. For average amplitude, significant effects for prenatal treatment were observed. Cocaine-exposed female rats demonstrated decreased ASR amplitude compared to offspring of pair-fed controls during both the initial test Session and following amphetamine administration as well. Overall, amphetamine increased startle. For latency, there were no significant treatment effects or effects of amphetamine administration. However, preplanned comparisons indicated that prenatal cocaine exposure interacted with trial block. Therefore, these data indicate that prenatal cocaine decreased startle amplitude in adults, primarily in females, and that startle-elicited amphetamine responses were dampened as well. The effects on latency indicate that amphetamine does not alter reaction times in prenatal cocaine exposed rats while it does in controls.

Animals↗
PubMed1996

A cytogenetic deletion, del(17)(q11.22q21.1), in a patient with sporadic neurofibromatosis type 1 (NF1) associated with dysmorphism and developmental delay.

We report the first visible cytogenetic deletion involving the NF1 gene in a patient with sporadic neurofibromatosis, dysmorphic features, and marked developmental delay. The combined evidence of molecular and cytogenetic techniques based on dosage reduction, hemizygosity for microsatellite markers, high resolution G banding, and FISH analysis, predicts this deletion to be approximately 7 Mb in size. Our findings highlight the importance of conducting a detailed cytogenetic and FISH analysis in patients with NF1 who have additional dysmorphic features or particularly severe learning difficulties.

Cells, Cultured↗
PubMed1995

Twenty-four cases of the EEC syndrome: clinical presentation and management.

Twenty-four cases of EEC syndrome were identified as part of a nationwide study. Ectodermal dysplasia, by study definition, was present in all cases and hair and teeth were universally affected. Nail dysplasia was present in 19 subjects (79%) and the skin was affected in 21 (87%). The presence of hypohidrosis was not noted as a predominant feature in the syndrome and its occurrence appeared to depend on the presence of all other features. Distal limb defects from simple syndactyly to tetramelic cleft hand and foot were identified, including preaxial anomalies. Orofacial clefting was identified in 14 cases (58%) and lacrimal duct anomaly in 21 (87%). Significant clinical problems encountered were chiefly cosmetic or ophthalmological, but conductive deafness and genitourinary problems in some cases required surgical intervention. Altered self-image was also noted in some cases. Multidisciplinary management is necessary with the early involvement of the clinical geneticist. Developmentally, the EEC syndrome and related disorders represent disorders of ectodermal/mesodermal interaction. Candidate regions include 7q21.3, the "ectrodactyly" locus; other candidates include developmental genes implicated in the ectodermal/mesodermal interactive process.

Abnormalities, Multiple↗
PubMed1994

Coarctation of the aorta in Kabuki syndrome.

The incidence of congenital heart defects in patients with Kabuki syndrome is estimated to be about 30%. To date, no specific type of heart malformation is known to be associated with the syndrome. A further 20 unselected children with Kabuki syndrome are presented. The incidence of heart abnormalities in these children is almost twice that previously reported (55%) and juxta-ductal coarctation occurs with a frequency of 25%.

Adolescent↗
PubMed1994

Sotos syndrome: a study of the diagnostic criteria and natural history.

Seventy-nine patients with a provisional diagnosis of Sotos syndrome were clinically assessed, and their photographs between the ages of 1 and 6 years evaluated. These photographs, together with photographs of first degree relatives, also at ages 1 to 6 years, were reviewed by four clinical geneticists. Forty-one probands (but no first degree relatives) were identified in whom the facial gestalt was thought to be characteristic of Sotos syndrome. Comparison of anthropometric measurements, bone age, and developmental delay in these 41 probands showed marked differences between them and the remaining 38 probands, and allowed the formulation of guidelines for the diagnosis of Sotos syndrome. Length was identified as the most significantly increased prenatal parameter. In childhood occipitofrontal head circumference (OFC), height, and weight were all increased. OFC remained above the 97th centile in all but one case throughout childhood and adulthood, whereas height and weight had a tendency to return towards the mean. This 'normalisation' was more pronounced in females and was probably related to their early puberty. Early developmental delay and an advanced bone age, seen in 100% and 84% respectively of study cases, may be invariable in Sotos syndrome, but selection bias and limited data prevented confirmation of this supposition. The authors suggest that facial gestalt, growth pattern, bone age, and developmental delay are the major diagnostic criteria. Using these criteria, no affected first degree relatives were identified. There were few long term medical complications in the probands, but behavioural difficulties caused considerable parental concern.

Abnormalities, Multiple↗
PubMed1994

Costello syndrome: natural history and differential diagnosis of cutis laxa.

Costello syndrome is emerging as a better delineated condition and should be included in the differential diagnosis of cutis laxa in association with postnatal growth retardation and developmental delay. We present a further case of Costello syndrome which illustrates the natural history of this condition.

Abnormalities, Multiple↗
PubMed1993

Long-term alterations in brain function following cocaine administration during the preweanling period.

This report examines the long-term effects of cocaine exposure during postnatal days (P) 11-20 on the metabolic function of major central neuronal systems. Cocaine (50mg/kg) or vehicle was administered subcutaneously to rat pups during P 11-20. At 60-64 days of age, the rats were examined for cerebral glucose metabolic patterns. In cocaine-treated females 18 of the 46 structures evaluated showed increased metabolic rates including 5 of 6 structures within the motor system and 7 of 17 limbic structures. No decreased rates were seen. In males, cocaine had no effects in the motor structures or hypothalamus while 2 of 17 structures within the limbic system showed decreased rates of glucose utilization and 2 of 11 structures within the sensory systems showed increased rates. These results indicate that female rats show greater long-term metabolic effects than males and that cocaine exposure during P 11-20 produces different metabolic effects than cocaine exposure during P 1-10 which we previously reported.

Animals↗