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R Cartwright

Publications and source records attributed to R Cartwright.

At least 37 records · Page 2Linked to original sources
PubMed1998

Isolation of novel human and mouse genes of the recA/RAD51 recombination-repair gene family.

Genes from the recA/RAD51 family play essential roles in homologous recombination in all organisms. Using sequence homologies from eukaryotic members of this family we have identified fragments of two additional mammalian genes with homology to RAD51. Cloning the full-length cDNAs for both human and mouse genes showed that the sequences are highly conserved, and that the predicted proteins have characteristic features of this gene family. One of the novel genes (R51H2) occurs in two forms in human cDNA, differing extensively at the 3' end, probably due to an unusual form of alternative splicing. The new genes (R51H2 and R51H3) were mapped to human chromosomes 14q23-24 and 17q1.2, respectively. Expression studies showed that R51H2 is expressed at lower levels than R51H3 , but that expression of both genes occurs at elevated levels in the testis compared with other tissues. The combination of gene structure conservation and the transcript expression patterns suggests that these new members of the recA/RAD51 family may also function in homologous recombination-repair pathways.

Amino Acid Sequence↗
PubMed1998

Epstein-Barr virus and Hodgkin's disease: further evidence for the three disease hypothesis.

The epidemiology of Hodgkin's disease suggests that it is a heterogeneous condition comprising more than one disease entity. The Epstein-Barr virus (EBV) is present in the Reed-Sternberg cells of a proportion of cases and is likely to play a role in the pathogenesis of these cases. In this study we show that EBV association rates vary with age at diagnosis. We suggest that Hodgkin's disease can be divided into three disease entities on the basis of EBV association and age, thereby providing biological support for the multiple aetiology hypothesis proposed by MacMahon (Cancer Res 1966; 26: 1189-1290).

Adolescent↗
PubMed1998

Seasonal variation in the incidence of Hodgkin's disease.

Earlier literature suggested there may be a seasonal rhythm of onset of Hodgkin's disease. This issue has been re-examined using population-based prospectively-collected data with high ascertainment levels. The Data Collection Study (DCS) of the Leukaemia Research Fund (LRF) Centre for Clinical Epidemiology (University of Leeds) generated the information used, which was based on a population of 13.5 million--about one quarter of England and Wales--over 10 years. The RYE histopathological classification was employed. The findings show that in patients with nodular sclerosing histopathology there was a highly significant circannual rhythm with a low amplitude (extent of seasonal variation) and a peak in March. A significant, but different, rhythm with a high amplitude and a peak in August was found in lymphocyte predominant Hodgkin's disease. However, this finding is less certain, due to smaller numbers and a lower significance level. The main conclusion is that there is a highly significant seasonality in nodular sclerosing Hodgkin's disease. The findings provide further evidence that nodular sclerosing and lymphocyte predominant may be two different diseases. The differing seasonality rhythms may provide aetiological clues.

Adolescent↗
PubMed1998

The changing incidence of lymphoproliferative disorders in Yorkshire.

Secular trends in the incidence of lymphoproliferative disorders on North and West Yorkshire and Humberside from 1985 to 94 were studied and changes in incidence by tumour subtype were analysed. Population-based data on the incidence of lymphoproliferative disorders were obtained from a specialist registry with a high level of ascertainment. Cases of chronic lymphocytic leukaemia and plasma cell myeloma were excluded and the remaining cases classified as Hodgkin's disease and non-Hodgkin's lymphoma (NHL). NHL were subdivided by site of origin and immunophenotype. Nodal B-cell lymphomas were further classified as diffuse large B-cell lymphoma, follicle centre lymphoma, mantle cell lymphoma and miscellaneous. During the study period there was a significant increase in total lymphoproliferative disorders with an average change of 2.5% per annum equivalent to 0.84/10,0000. Most of this increase was due to an increasing incidence of extranodal B-cell lymphomas and peripheral T-cell lymphomas. A numerically small but significant increase in diffuse large B-cell lymphomas was seen. There was no significant increase in other subtypes. The increased incidence of lymphomas in the area studied is mainly due to changes in two specific subgroups. There are several reasons why changes in extranodal B-cell lymphoma and peripheral T-cell lymphoma may have been particularly affected by changing diagnostic practices. Epidemiological studies of particular subtypes of lymphoproliferative disorder facilitate the identification of environmental factors involved in the pathogenesis of these tumours.

Adolescent↗
PubMed1998

Incidence and time trends in Hodgkin's disease: from parts of the United Kingdom (1984-1993).

Over 3,000 cases of Hodgkin's Disease diagnosed between 1984-93 were used to examine incidence and time trends. These data are part of the Leukaemia Research Fund's specialist Data Collection Study, which is the only large, population-based data set of its type in Europe. The age specific incidence curves showed different patterns for nodular sclerosis contrasted with all other subtypes combined (non-nodular sclerosis). For nodular sclerosis, there was a female excess for young adults, while for non-nodular sclerosis a gradual rise in incidence with age in both sexes was observed. Incidence varied over time, showing a complex pattern with a decreasing trend in males in all Rye-subtypes and no significant change among females diagnosed with nodular sclerosis. These complex patterns of change are different from those seen in other countries. It is concluded that the results provide clear evidence of the heterogeneity of Hodgkin's disease between the sexes and between subtypes, which should be taken into account in future studies.

Adolescent↗
PubMed1997

Changing trends in the incidence of non-Hodgkin's lymphoma in Europe. Biomed Study Group.

Non-Hodgkin's lymphoma (NHL) is not a uniform disease entity, and in order to investigate the reported changes in incidence we have set up a study in seven population-based cancer registries in Europe. The study is designed to look at changes in the incidence of total NHL and disease subgroups using standard definitions and methodology. The registries are based in Leeds, Dijon, Kuopio, Odense, Florence, Eindhoven, and Ragussa. The classification system we have used is based on the REAL classification and has utility for epidemiological studies. We have used it to convert data sets which have utilized both local cases and the ICD-O classification. In order to improve data reproducibility, CLL/LL, myeloma/MGUS, lymphoblastic disease, and Hodgkin's disease have been excluded because of the difficulty in defining incident cases accurately. The preliminary results of this study show that there is still an upward trend in incidence rate and that in Yorkshire this is 3% per annum in total NHL. The subgroups which are increasing are extranodal and nodal peripheral T-cell lymphoma. Similar increases in incidence have been reported for the other registries. We conclude that there is a continued upward trend in incidence of NHL, the causes of which are uncertain.

Europe↗
PubMed1996

An outbreak of viral gastroenteritis on a cruise ship.

Three hundred and seventy-eight passengers reported gastroenteritis during four cruises in the western Mediterranean on consecutive weeks of 1995. The rate at which cases were reported each day increased on the fourth cruise. The ship's owner commissioned an epidemiological investigation from the PHLS Communicable Disease Surveillance Centre. Cases reported explosive vomiting and diarrhoea, which lasted from 24 hours to five days, and were suggestive of viral gastroenteritis. No food handlers reported illness, but enquiries suggested that some had been ill and treated themselves. No bacterial pathogens were isolated from faecal specimens provided by cases or from water, food, and environmental samples taken from the galley. Small round structured viruses (SRSV) were identified by reverse transcriptase polymerase chain reaction in two faecal specimens and one specimen of vomit from people who became ill during the fourth cruise. SRSV was also identified in one faecal specimen by electron microscopy. Environmental inspection revealed inappropriate food handling, hygiene, and storage. During one 24 hour period no chlorine was detectable in the water. A case control study conducted on the fourth cruise sought details of exposure to various foodstuffs, unbottled water, and various parts of the ship. No significant associations were found between illness and any exposures. The evidence strongly suggested a continuing outbreak of SRSV infection transmitted from person to person. Some passengers remained on board for a second week and could have transmitted their infection to new arrivals. The ship was cleared and disinfected at the end of the fourth cruise in order to interrupt transmission. Fewer than 10 cases presented in each of the fifth and sixth cruises.

Adolescent↗
PubMed1995

Oral appliances for the treatment of snoring and obstructive sleep apnea: a review.

This paper, which has been reviewed and approved by the Board of Directors of the American Sleep Disorders Association, provides the background for the Standards of Practice Committee's parameters for the practice of sleep medicine in North America. The 21 publications selected for this review describe 320 patients treated with oral appliances for snoring and obstructive sleep apnea. The appliances modify the upper airway by changing the posture of the mandible and tongue. Despite considerable variation in the design of these appliances, the clinical effects are remarkably consistent. Snoring is improved and often eliminated in almost all patients who use oral appliances. Obstructive sleep apnea improves in the majority of patients; the mean apnea-hypopnea index (AHI) in this group of patients was reduced from 47 to 19. Approximately half of treated patients achieved an AHI of < 10; however, as many as 40% of those treated were left with significantly elevated AHIs. Improvement in sleep quality and sleepiness reflects the effect on breathing. Limited follow-up data indicate that oral discomfort is a common but tolerable side effect, that dental and mandibular complications appear to be uncommon and that long-term compliance varies from 50% to 100% of patients. Comparison of the risk and benefit of oral appliance therapy with the other available treatments suggests that oral appliances present a useful alternative to continuous positive airway pressure (CPAP), especially for patients with simple snoring and patients with obstructive sleep apnea who cannot tolerate CPAP therapy.

Evaluation Studies as Topic↗
PubMed1994

The increasing incidence of non-Hodgkin's lymphoma (NHL): the possible role of sunlight.

This review critically examines the rise in incidence in non-Hodgkin's Lymphoma (NHL) in selected parts of the world and concludes that much of the increase is likely to be due to unknown biological factors. It postulates that one reasonable explanation for the rise in incidence of NHL is the ever increasing exposure of populations, particularly in the Northern Hemisphere, to sunlight. Support for the hypothesis is supplied from both epidemiological evidence and studies of the responses of lymphocytes to ultra-violet light in both in vitro and in vivo experimental work.

Humans↗
PubMed1994

Homicidal somnambulism: a case report.

A case of a homicide and an attempted homicide during presumed sleepwalking is reported in which somnambulism was the legal defense and led to an acquittal. Other possible explanations including complex partial seizures, dissociative state, rapid eye movement sleep behavior disorder and volitional waking behavior are discussed. The evidence supporting the probability that this act occurred during an episode of somnambulism and sleep-related confusional arousal is reviewed and weighed. This evidence includes personal and family history of somnambulism and related disorders; neurological, psychiatric and psychological assessments; presence of possible precipitating factors; and polysomnographic data.

Adult↗
PubMed1992

Evidence for an environmental effect in the aetiology of insulin dependent diabetes in a transmigratory population.

OBJECTIVE: To examine whether children of families moving from an area of low incidence of childhood diabetes to one which is higher show a corresponding rise in disease incidence. DESIGN: Disease incidence study over 12 years. SETTING: Bradford District Metropolitan Council area. SUBJECTS: All subjects aged 0-16 years resident within the study area. MAIN OUTCOME MEASURES: The incidences of childhood diabetes in Asian and non-Asian families. RESULTS: The incidence of diabetes in Asian children increased from 3.1/100,000 per year in 1978-81 to 11.7/100,000 per year in 1988-90 (chi 2 for trend = 4.95, df = 1, p = 0.026) whereas that for other children remained constant at 10.5/100,000 per year. Over the entire study period rates were lower in Asian females (4.9/100,000 per year) than in Asian males (8.8/100,000 per year) whereas the reverse was true for other children (males 9.2/100,000 per year; females 12.0/100,000 per year) (test for common odds ratio: chi 2 = 3.81, df = 1, p = 0.052). CONCLUSIONS: Offspring of this transmigratory population had a rising incidence of childhood diabetes which was approaching that of the indigenous population. The data provide strong evidence for an environmental effect in the aetiology of insulin dependent diabetes.

Adolescent↗
PubMed1991

A comparative study of treatments for positional sleep apnea.

Sixty male patients all with apnea plus hypopnea indices (A + HI) above 12.5, who met a criterion of positionality by having two or more times the rate of these events during supine sleep in comparison to their lateral sleep rate, were randomly assigned to one of four treatments for 8 weeks. All were restudied for two nights, one with and one without treatment devices. On treatment more than half the patients in each group reduced their A + HI to within normal limits and a third remained WNL without the use of devices. Half of those trained to sleep in the lateral position with the help of an alarm maintained this learning without the alarm as did half of those who were encouraged to learn this sleep posture on their own. There is an additive effect for the positional patient from wearing a tongue retaining device (TRD) if they continue to sleep in the supine position. Factors associated with successful treatment include overall severity, severity in the lateral position, weight, weight change, nasal patency and motivation to help their condition.

Behavior Therapy↗
PubMed1990

Palmar keratoses in family members of individuals with bladder cancer.

A total of 270 bladder cancer cases, 178 first-degree relatives and 127 spouses of the bladder cancer cases and 329 hospital controls were studied to evaluate the association between palmar keratoses, bladder cancer and environmental and genetic factors. Crude prevalences of keratoses in the 4 groups were 67, 54, 42 and 23%, respectively. Logistic regression models showed that bladder cancer patients had a raised risk of having palmar keratoses relative to hospital controls (odds ratio = 6.95; 95% CI: 4.77-10.12) whereas blood-relatives and spouses had significantly increased odds ratios only if the case in their family (or some other blood-relative) possessed keratoses. Among several environmental and behaviour factors, only cigarette smoking was significantly associated with increased risk (odds ratio = 2.32; 95% CI: 1.63-3.29). The data suggest a genetic component may influence the occurrence of palmar keratoses, but some unknown environmental agent appears to be causing the association between spouses.

Adult↗
PubMed1990

Investigation of spacial clustering of rare diseases: childhood malignancies in North Humberside.

STUDY OBJECTIVE: The aims of the study were (1) to test for uniformity of distribution of childhood leukaemias and other malignancies; and (2) to consider the aetiological implications of unusual distributions. DESIGN: A test for spacial clustering was applied using a method which allows for unequal distribution of the population at risk and avoids using census data to provide population denominators. When clustering was identified, four possible aetiological links which had already been suggested to the Leukaemia Research Fund Centre were examined in a local area. SETTING: The study was carried out in the Yorkshire Health Region in the north of England. PATIENTS: 144 children under 15 years of age with a diagnosis of malignant disease known to the Yorkshire Regional Childhood Tumour Registry between 1974 and 1986 were included in the analysis. Of these 53 had leukaemias and nine had lymphomas. MEASUREMENTS AND RESULTS: Significant localised clustering was found in North Humberside, though not in the whole of the Yorkshire Health Region. A number of clustered cases were identified, some of whom were in a post code sector, Hull 10, to the west of Kingston-upon-Hull, about which concern had been expressed since 1985. There was however no evidence that disease clustering was confined to this area. Four previously suggested hypotheses about causation in this particular area were examined but the results were negative or inconclusive. CONCLUSIONS: The identification of spacial clustering must be seen as only the first step in a series of investigations; it can only rarely lead to aetiological conclusions by itself, but it can motivate and target other investigations.

Adolescent↗
PubMed1986

Severity of sleep apnea as a predictor of successful treatment by palatopharyngoplasty.

As awareness and understanding of obstructive sleep apnea has increased so has the number of treatments for this disorder. Options include surgical procedures: tracheostomy, palatopharyngoplasty (PPP), and mandibular advancement. Other treatments are medication, nasal CPAP, Tongue Retaining Device, and a position alarm. With these numerous choices available, it is important that reliable indicators be developed to guide treatment choice. And although PPP surgery is a one-time intervention with possibility of permanent correction, reports of percentages of successful treatment have varied widely from 85% to 0%. This has led us to investigate predictors of successful treatment. Twenty-two patients treated with PPP following their diagnosis by standard clinical polysomnography were restudied an average of 8 weeks later. When 11 successful cases were compared to 11 unsuccessful cases, successes were found to be initially more severely apneic (mean AI = 90.55 versus 49.45). Palatopharyngoplasty appears to be most appropriate for the sleep apnea patient whose apnea index is 70 or above and less effective for milder cases.

Adult↗