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P Young

Publications and source records attributed to P Young.

At least 55 records · Page 3Linked to original sources
PubMed2001

Mutation analysis of 4 candidate genes for hereditary neuralgic amyotrophy (HNA).

Hereditary neuralgic amyotrophy (HNA) is a rare autosomal dominant disorder. It is characterised by recurrent episodes of focal neuropathy involving the brachial plexus. Genetic linkage analysis has mapped HNA to chromosome 17q25 within a 3.5-cM interval flanked by the short tandem repeat markers D17S785 and D17S802. Here, we report the mutation analysis of four candidate genes. Mutation analysis was performed on the complete coding regions of these genes. Several exonic and intronic single nucleotide polymorphisms were detected. However, no disease-causing mutations were found, indicating that these genes are most probably not involved in the pathogenesis of HNA. In addition, we have characterised and localised a putative pseudogene of the SEC14-like 1 gene.

Brachial Plexus Neuritis↗
PubMed2001

Association between early sexual abuse and adult HIV-risky sexual behaviors among community-recruited women.

OBJECTIVE: The first purpose was to determine whether sexual abuse involving penetration that occurred in childhood only, adolescence only, or both childhood and adolescence differently impacted whether community-recruited women had ever traded sex for money or drugs, their number of recent sex partners, and the number of times they had engaged in recent unprotected sex. The second purpose was to assess the mediating effects of adulthood rape, recent drug use, and recent sex with an injection drug user on these three HIV-risky sexual behaviors. METHOD: Women (n = 1,490) recruited from three US sites were questioned about their childhood and/or adolescent sexual abuse histories, adulthood rape experiences, recent drug use, and adult HIV-risky sexual behaviors via structured interviews. RESULTS: One-third of the women reported having experienced sexual abuse involving penetration in childhood and/or adolescence. Overall, regression analyses indicated a significant relationship between early sexual abuse and adult risky behaviors; rape in adulthood mediated this relationship for all three HIV-risky behaviors. Abuse that occurred in childhood only and abuse that occurred in both childhood and adolescence had a stronger impact on later risky behaviors than did abuse that occurred in adolescence only. CONCLUSIONS: Because childhood constitutes a critical period in individuals' sexual, social, and personal development, sexual abuse precipitated during this time may distort women's constructions of sex and sexuality. Women abused in childhood may therefore engage in HIV-risky sexual behaviors to a greater extent than women abused in adolescence as a result of these disruptions to their development. Rape in adulthood appears to intensify the effects of early sexual abuse,

Adolescent↗
PubMed2001

Disease mechanisms and potential therapeutic strategies in Charcot-Marie-Tooth disease.

Until 10 years ago, the genetic basis of Charcot-Marie-Tooth (CMT) disease was largely unknown. With the finding of an intrachromosomal duplication on chromosome 17 in 1991, associated with the most commonly found subtype CMT1A, and the discovery of a point mutation in the peripheral myelin protein-22 (pmp22) gene in the Trembler mouse in 1992, the groundwork was laid down for a novel chapter in the elucidation of the molecular basis of this large group of peripheral neuropathies. In the meantime, several different genes have been found to be associated with different forms of demyelinating and axonal forms of CMT. In this review, we will summarize what is known today about the genetics of this group of disease which constitute the most common known monogenetic disorder affecting the nervous system in man, the animal models that have been generated, and what we have learned about the underlying disease mechanisms. Furthermore, we will review how this gain of knowledge about CMT may open new avenues to the development of novel treatment strategies.

Animals↗
PubMed2001

Caesarean section by choice could fulfil the inverse care law.

We have assessed knowledge about caesarean sections in a group of North Staffordshire Hospital professionals and patients. Those who were more interested in having a caesarean section without medical indication were the nulliparous health professionals, the majority of whom thought they should be able to choose this option. Paradoxically, this was also the group who were most likely to consider that caesarean section is more expensive and dangerous. The explanation may be that they also felt it to be an easier, less painful and more convenient option.

Attitude of Health Personnel↗
PubMed2001

The natural history of Hendra and Nipah viruses.

Pteropid bats (flying foxes), species of which are the probable natural host of both Hendra and Nipah viruses, occur in overlapping populations from India to Australia. Ecological changes associated with land use and with animal husbandry practices appear most likely to be associated with the emergence of these two agents.

Animals↗
PubMed2001

Why KY?

Explore the source record for details and available documents.

Gels↗
PubMed2001

Antral motility measurements by magnetic resonance imaging.

Magnetic resonance imaging has been recently proposed as a promising, noninvasive technique to assess the motility of the gastric antrum. However, so far the reproducibility and dependence on test meal composition has not been evaluated. In this study, snapshot echo-planar magnetic resonance imaging was used to measure the frequency, propagation speed and percentage occlusion of antral contractions in 28 healthy volunteers. They were fed either liquid (n=12), mixed liquid/solid (n=8) or mixed viscous/solid (n=8) nutrient (1350 kJ) test meals, and a total of 208 motility measurements were performed. No effect of meal type on antral motility parameters was observed. Antral contraction frequency was 3.0 +/- 0.2 min(-1) (mean +/- SD, n=164), propagation speed was 1.6 +/- 0.2 mm s(-1) (n=164) and the percentage occlusion was 58 +/- 14% (n=76). Overall, 21% of measurements did not provide useful antral motility data, because, in the supine position, the antrum was not filled by the test meal. Simple methods to overcome this and reduce scanning time to a minimum are proposed. The results show that the noninvasive magnetic resonance imaging evaluation of antral motility is accurate and reproducible and has potential to become a standard tool for such investigations.

Adolescent↗
PubMed2001

Haemodynamic, invasive and echocardiographic monitoring in the hypertensive parturient.

AIM: To determine the clinical usefulness of invasive and non-invasive haemodynamic assessment in pre-eclampsia. METHOD: A systematic review of the literature was undertaken, using a MEDLINE electronic search using a combination of MESH headings and textwords. Over 1500 abstracts were perused; we obtained 156 full papers that were related to the subject matter. Of the full papers, 55 yielded relevant information. Hand-searching the reference lists of the retrieved papers completed the search. RESULTS: There are no data from randomized controlled clinical trials illustrating the clinical usefulness of pulmonary artery catheters or echocardiographic techniques in hypertensive pregnancy. There are a wealth of data illustrating the haemodynamic profiles of both untreated and treated pre-eclamptic women. Data are also available comparing right heart and left heart filling pressures, demonstrating a relatively poor correlation between the two values. The clinical impact of either measurement is unclear. Data are available illustrating the correlation between echocardiographic techniques and pulmonary artery catheterization.

Catheterization, Swan-Ganz↗
PubMed2001

A systematic review of oral treatments for fungal infections of the skin of the feet.

OBJECTIVE: To synthesize the evidence for the effectiveness and cost-effectiveness of oral treatments for fungal infections of the skin of the feet. DESIGN: Systematic review. INTERVENTIONS: Oral treatments for fungal infections. METHODS: Ten electronic databases, four journals and the bibliographies of all review papers identified were searched. The authors also wrote to international pharmaceutical companies and all podiatry schools in the UK. The studies selected were randomized trials of clinically diagnosed fungal skin infections of the foot that confirmed cure by culture and microscopy. Two reviewers independently selected trials and abstracted data using a structured tool including 12 recognized quality criteria. RESULTS: Of 26 trials identified, 12 met the inclusion criteria and evaluated five different treatments. Single placebo-controlled trials showed that terbinafine and itraconazole were both effective. Two trials showed that terbinafine cures 50% more patients than griseofulvin. Four trials compared terbinafine with itraconazole, one showed that terbinafine given for 2 weeks had a better cure rate than 2 weeks of itraconazole, but the other three showed that it was no better than 4 weeks of itraconazole. CONCLUSIONS: There is significant evidence that terbinafine is more effective than griseofulvin, though more costly. There is weak evidence that terbinafine may be more cost-effective than itraconazole. Firm recommendations about the choice between terbinafine and the azoles need further research.

Administration, Oral↗
PubMed2001

Regulation of Schwann cell proliferation and apoptosis in PMP22-deficient mice and mouse models of Charcot-Marie-Tooth disease type 1A.

Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by an increased dosage of the peripheral myelin protein 22 (PMP22) gene or by point mutations affecting the same gene. Based on in vitro data, PMP22 might be involved, besides in its proven role in the regulation of myelination and myelin maintenance, in the control of Schwann cell proliferation and programmed cell death. In this report, we have used mice lacking PMP22 and mouse models for CMT1A to analyse Schwann cell proliferation and apoptosis in vivo during postnatal sciatic nerve development. Our results show that there is no significant change in the number of Schwann cells at postnatal day 1 in the analysed PMP22 mutants compared with the corresponding wild-type animals. Furthermore, the rate of proliferation also was not changed at this early developmental time point. In contrast, cell density and proliferation rates were increased, albeit with different kinetics, in all PMP22 mutants later in development. The increase in proliferation is paralleled by a higher number of apoptotic Schwann cells found in the nerves. Thus, increased Schwann cell proliferation and apoptosis, but only in later development and in adults, are hallmarks of PMP22 mutant mice, regardless of whether increased or decreased PMP22 gene dosage or point mutations affecting the PMP22 gene are responsible for the resulting demyelinating, dysmyelinating or amyelinating phenotypes.

Animals↗
PubMed2001

A study of infertility treatment and melanoma.

This study examined the possible association between melanoma and exposure to fertility drugs, specifically clomiphene citrate, human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG). A cohort of 3186 women who attended a fertility clinic between 1 January 1980 and 31 December 1990 was studied; by January 1996, 14 women had been diagnosed with primary melanoma. Details of fertility treatment were extracted from the clinical records. The incidence of melanoma in the cohort resembled that of the female Queensland population (standardized incidence ratio = 0.89, 95% confidence interval [CI] = 0.54-1.48). Exposure to clomiphene citrate, HMG or HCG did not affect the incidence of melanoma. Women with infertile partners who were treated with fertility drugs were at increased risk of melanoma (odds ratio [OR] = 3.17, 95% CI = 1.01-9.98). Compared with women exposed only to clomiphene citrate and HMG, a lower incidence of melanoma was observed among those who received HCG as well (OR = 0.10, 95% CI = 0.02-0.42). Women exposed to two or more cycles of either clomiphene citrate (OR = 0.27, 95% CI = 0.08-0.94) or HMG (OR = 0.23, 95% CI = 0.07-0.84) had a significant reduction in melanoma risk compared with women exposed to no or one cycle. In summary, a woman's infertility per se was not found to be associated with melanoma, while exposure to fertility drugs was positively associated with melanoma in women with infertile partners and negatively associated in women with low doses of fertility drugs.

Adult↗
PubMed2001

Management of massive postpartum haemorrhage: use of a hydrostatic balloon catheter to avoid laparotomy.

Postpartum haemorrhage remains a significant complication of childbirth in the UK and worldwide. The most common cause of postpartum haemorrhage is uterine atony, but placent accreta is becoming more frequent. In these situations tamponade may be required. The successful use of the inflated stomach balloon (300ml) of a Sengstaken-Blakemore tube has been reported previously. We describe an innovative method of 'tamponade' which is simple and effective, using the Rüsch urological hydrostatic balloon catheter. In two cases of failed medical therapy for PPH, where the catheter has been tried, further surgical interventions have been avoided.

Adult↗
PubMed2001

An investigation of condom use by frequency of sex.

OBJECTIVES: To examine the association between condom use and frequency of sex across sexual partner types. METHODS: Data were collected from African American drug users residing in Washington, DC. Participants were asked to provide the first name of the last three partners with whom they had had vaginal sex, to define the type of relationship, the number of times they had had vaginal sex in the last 30 days with each partner, and whether they had used a condom during their last sexual encounter with each partner. Condom use was examined by frequency of sex in the past 30 days controlling for partner type. RESULTS: Frequency of sexual encounters varied by partner type. The largest number of sexual encounters was with casual partners, followed by commercial and primary partners, respectively. Within partner types, participants had sex most frequently with primary partners. Condom use was lowest within primary partner relationships. Regardless of partner type, condom use varied consistently depending on the frequency of sex with the same partner. CONCLUSIONS: Condom use is related to the frequency of sex between partners when partner type is controlled. The association between frequency of sex and condom use is independent of partner type, suggesting that partner type may become less influential in determining condom use as the frequency of sex increases. This finding suggests that contextual factors determining condom use go beyond partner type designations and include other relationship variables.

Adult↗
PubMed2001

Assessment of antral grinding of a model solid meal with echo-planar imaging.

Mathematical modeling of how physical factors alter gastric emptying is limited by lack of precise measures of the forces exerted on gastric contents. We have produced agar gel beads (diameter 1.27 cm) with a range of fracture strengths (0.15-0.90 N) and assessed their breakdown by measuring their half-residence time (RT(1/2)) using magnetic resonance imaging. Beads were ingested either with a high (HV)- or low (LV)-viscosity liquid nutrient meal. With the LV meal, RT(1/2) was similar for bead strengths ranging from 0.15 to 0.65 N but increased from 22 +/- 2 min (bead strength <0.65 N) to 65 +/- 12 min for bead strengths >0.65 N. With the HV meal, emptying of the harder beads was accelerated. The sense of fullness after ingesting the LV meal correlated linearly (correlation coefficient = 0.99) with gastric volume and was independently increased by the harder beads, which were associated with an increased antral diameter. We conclude that the maximum force exerted by the gastric antrum is close to 0.65 N and that gastric sieving is impaired by HV meals.

Adult↗
PubMed2001

Effect of meal viscosity and nutrients on satiety, intragastric dilution, and emptying assessed by MRI.

The relationship between the intragastric distribution, dilution, and emptying of meals and satiety was studied using noninvasive magnetic resonance imaging techniques in 12 healthy subjects with four polysaccharide test meals of varying viscosity and nutrient content as follows: 1) low-viscosity nonnutrient, 2) low-viscosity nutrient, 3) high-viscosity nonnutrient, and 4) high-viscosity nutrient. Increasing the nutrient content of the high-viscosity meal delayed gastric emptying from 46 +/- 9 to 76 +/- 6 min (P < 0.004), whereas increasing viscosity had a smaller effect. The volume of secretions within the stomach 60 min after ingestion was higher for the high-viscosity nutrient meal (P < 0.04). A simple model to calculate the total volume of secretion added to the test meal is presented. Color-coded dilution map images showed the heterogeneous process of progressive gastric dilution of high-viscosity meals, whereas low-viscosity meals were uniformly diluted. Fullness was found to be linearly related to total gastric volumes for the nutrient meals (R(2) = 0.98) and logarithmically related for the nonnutrient meals (R(2) = 0.96). Fullness was higher for high- compared with low-viscosity meals (P < 0.02), and with the nutrient meals this was associated with greater antral volumes (P < 0.05).

Adult↗
PubMed2001

Reducing risk by improving standards of intrapartum fetal care.

Confidential Enquiries into Stillbirths and Deaths in Infancy (CESDI) have pointed to a high frequency of suboptimal intrapartum fetal care of a kind that, in the event of an adverse outcome, is hard to defend in court. In an effort to minimize liability, various strategies were applied in a district hospital labour ward--guidelines, cyclical audit, monthly feedback meetings and training sessions in cardiotocography (CTG). The effects of these interventions on quality of care was assessed by use of the CESDI system in all babies born with an Apgar score of 4 or less at 1 min and/or 7 or less at 5 min. 540 babies (4.3%) had low Apgar scores, and neither the percentage nor gestational age differed significantly between audit periods. In the baseline audit, care was judged suboptimal (grade II/III) in 14 (74%) of 19 cases, and in the next four periods it was 23%, 27%, 27% and 32%. In the latest audit period, after further educational interventions, it was 9%. Many of the failures to recognize or act on abnormal events were related to CTG interpretation. After the interventions there was a significant increase in cord blood pH measurement. There were no differences between audit periods in the proportion of babies with cord pH < 7.2. These results indicate that substantial improvements in quality of intrapartum care can be achieved by a programme of clinical risk management.

Apgar Score↗