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H Rees

Publications and source records attributed to H Rees.

At least 19 recordsLinked to original sources
PubMed2006

The use of time-series data in the assessment of macrobenthic community change after the cessation of sewage-sludge disposal in Liverpool Bay (UK).

Sewage sludge was disposed of in Liverpool Bay for over 100 years. Annual amounts increased from 0.5 million tonnes per annum in 1900 to approximately 2 million tonnes per annum by 1995. Macrofauna and a suite of environmental variables were collected at a station adjacent to, and a reference station distant from, the disposal site over 13 years, spanning a pre- (1990-1998) and post- (1999-2003) cessation period. Univariate and multivariate analyses of the time-series data showed significant community differences between reference and disposal site stations and multivariate analyses revealed station-specific community development post-disposal. Temporal variability of communities collected at the disposal station post-cessation was higher than during years of disposal, when temporally stable dominance patterns of disturbance-tolerant species had established. Alterations of community structure post-disturbance reflected successional changes possibly driven by facilitation. Subtle faunistic changes at the Liverpool Bay disposal site indicate that the near-field effects of the disposal of sewage sludge were small and therefore could be considered environmentally acceptable.

Analysis of Variance↗
PubMed2006

Rat Schwann cells express M1-M4 muscarinic receptor subtypes.

The expression of different muscarinic receptor subtypes was analyzed in immature Schwann cells obtained from sciatic nerve of 2-day neonatal rats. By using RT-PCR analysis, we demonstrated the presence of M1, M2, M3, and M4 receptor subtypes in cultured Schwann cells, with M2 displaying the highest expression levels. Muscarinic subtypes were also quantified by immunoprecipitation and [3H]QNB binding. With this approach, we found the levels of receptor expression to be M2 > M3 > M1. M4 is expressed at very low levels, and M5 receptor was not detectable. Moreover, we also demonstrated that stimulation of the receptors by muscarinic agonists activates previously described signal transduction pathways, leading to a decrease of cAMP and an increase of IP3 levels not associated with an efficient intracellular Ca2+ release. The presence and activity of particular muscarinic receptors in immature Schwann cells suggest that ACh may play an important role in Schwann cell development.

Analysis of Variance↗
PubMed2005

Collecting duct carcinoma of the renal medulla presenting with paraplegia.

We report an interesting case of a patient with collecting duct carcinoma arising from the left kidney who presented with paraplegia secondary to metastases. The diagnosis was based on CT and histology. To our knowledge this is the first case of collecting duct carcinoma to present with paraplegia. The literature review also highlights the rarity of this disease with less than a hundred cases reported to date and the aggressive nature and poor prognosis despite prompt interventions.

Adult↗
PubMed2003

Risk of recurrent hydatidiform mole and subsequent pregnancy outcome following complete or partial hydatidiform molar pregnancy.

OBJECTIVE: To determine pregnancy outcome, including the rate of repeat molar pregnancy, following histologically confirmed complete or partial hydatidiform mole. DESIGN: Retrospective review of a large supraregional database of registrations for gestational trophoblastic disease. SETTING: Supraregional Trophoblastic Disease Unit, London. SAMPLE: Women with pregnancies affected by complete or partial hydatidiform mole registered between 1992 and 1998. METHODS: All patients with a diagnosis of histologically confirmed complete or partial hydatidiform mole were identified and data on subsequent pregnancies compared between groups using comparison of proportion test. MAIN OUTCOME MEASURES: Pregnancy outcome by partial or complete mole subtype, with particular regard to risk of subsequent molar pregnancy. RESULTS: Of 2578 complete moles, the subsequent pregnancy was affected by hydatidiform mole in 27 (1.9%) cases, including 22 (81%) complete moles and 5 (19%) partial moles. Of 2627 partial moles, the subsequent pregnancy was also molar in 25 (1.7%) cases, including 17 (68%) partial moles and 8 (32%) complete moles. Overall recurrence risk for molar pregnancy was 1.8% (1 in 55), or a 20-fold increase compared with the background risk. Of 27 cases with repeat complete moles, three had further complete moles, suggesting the recurrence risk following two previous complete moles is approximately 10%. There were no other significant differences in pregnancy outcome between cases with previous complete or partial hydatidiform mole and that expected in an unselected obstetric population. CONCLUSIONS: Women having a pregnancy affected by a histologically confirmed complete or partial hydatidiform mole may be counselled that the risk of repeat mole in a subsequent pregnancy is about 1 in 60 and if this were to occur, the majority of cases will be of the same type of mole as the preceding pregnancy. However, >98% of women who become pregnant following a molar conception will not have a further hydatidiform mole and these pregnancies are at no increased risk of other obstetric complications.

Adolescent↗
PubMed2003

Management of incomplete abortion in South African public hospitals.

OBJECTIVE: To describe the current management of incomplete abortion in South African public hospitals and to discuss the extent to which management is clinically appropriate. DESIGN: A multicentre, prospective descriptive study. SETTING: South African public hospitals that manage gynaecological emergencies. SAMPLE: Hospitals were selected using a stratified random sampling method. All women who presented to the above sampled hospitals with incomplete abortion during the three week data collection period in 2000 were included. METHODS: A data collection sheet was completed at the time of discharge for each woman admitted with a diagnosis of incomplete, complete, missed or inevitable abortion during the study period. Information gathered included demographic data, clinical signs and symptoms at admission, medical management, surgical management, anaestetic management, use of blood products and antibiotics and complications. Three clinical severity categories were used for the purpose of data analysis and interpretation. MAIN OUTCOME MEASURES: Detail of medical management, detail of surgical management, use of blood products and antibiotics, methods of analgesia and anaesthesia used, and use of abortifacients. RESULTS: There is a trend towards low cost technology such as the use of manual vacuum aspiration and sedation anaesthesia; however, this is mainly limited to the better resourced tertiary hospitals linked to academic units. The use of antibiotics and blood products has decreased but much of the use is inappropriate. The use of abortifacients does include some use of misoprostol but merely as an adjunct to surgical evacuation. CONCLUSIONS: The management of incomplete abortion remains a problem in South Africa, a low income country that is still managing a common clinical problem with costly interventions. The evidence of a trend towards low cost technology is promising, albeit limited to tertiary centres. This study has given us information as how to best address this problem. More training in low cost methods is needed, targeting in particular the district and regional hospitals, and reinforced by skills training focussed mainly on undergraduates and midwife post-abortion care programmes.

Abortifacient Agents↗
PubMed2003

Can enquiries into severe acute maternal morbidity act as a surrogate for maternal death enquiries?

OBJECTIVE: To assess whether severe acute maternal morbidity (SAMM, 'near misses') can be used as a surrogate of an analysis of maternal deaths to describe the pattern of severe maternal disease and avoidable factors related to it. DESIGN: Prospective, descriptive study. SETTING: A SAMM and maternal mortality audit was conducted in three clearly defined geographical areas, consisting of rural and urban settings in South Africa. POPULATION: Indigent black African pregnant women. METHOD: Cases of SAMM and maternal deaths were collected in the areas and a comparison was made of the disease profiles and avoidable factors, missed opportunities and substandard care. MAIN OUTCOME MEASURES: The proportion of primary obstetric causes and avoidable factors in women with SAMM and maternal deaths, and the mortality indices of the primary obstetric causes of death and organ system dysfunction. RESULTS: A total of 423 women with SAMM and 128 maternal deaths were collected over two years. Demographic factors were similar between the groups except that significantly more maternal deaths had not attended any antenatal care. The primary obstetric causes of SAMM and maternal death did not correlate. The four most common causes of SAMM were complications of hypertension (27.2%), postpartum haemorrhage (18.0%), antepartum haemorrhage (12.8%) and abortion (11.3%), whereas the four most common causes of maternal death were non-pregnancy related sepsis (26.6%), complications of hypertension (23.4%), pre-existing medical disease (14.1%) and abortion (10.9%). The types of avoidable factors were similar between both groups although administrative factors occurred significantly more frequently in the maternal death group as did poor problem identification and monitoring. CONCLUSION: Review of SAMM gives a different disease pattern to that obtained from maternal death audits. However, in diagnosing inadequacies in the health system, similar information was obtained.

Adult↗
PubMed2002

Risk of partial and complete hydatidiform molar pregnancy in relation to maternal age.

All cases of first histologically confirmed complete and partial moles registered between 1985 and 1999 were identified from the database of a Trophoblastic Disease Registration Centre. The maternal age distribution at diagnosis was calculated for the 7916 molar pregnancies and compared with the maternal age distribution of an unselected population of women from a routine obstetric database. Likelihood ratios were calculated for complete and partial molar pregnancies by maternal age. A positive relationship was found between the risk of molar pregnancy and both upper and lower extremes of maternal age (> or = 45 years and < or = 15 years, respectively). This association, although present for both complete and partial moles, is much greater for complete mole at all maternal ages, and the degree of risk is much greater with older (> or = 45 years) rather than younger (< or = 15 years) maternal age. This study provides, for the first time, data regarding specific risk of partial versus complete hydatidiform mole with maternal age.

Adolescent↗
PubMed2001

The diagnostic implications of routine ultrasound examination in histologically confirmed early molar pregnancies.

OBJECTIVE: Early ultrasound examination is being used increasingly in the diagnosis of molar pregnancy. The aim of this study was to examine the diagnostic implications of routine ultrasound examination for histologically confirmed molar pregnancies. METHODS: This was a retrospective review of sonographic and histological findings in a series of consecutive cases referred to the National Trophoblastic Disease Surveillance Centre with suspected molar pregnancies. In 194 cases referred to the center over a 6-month period in whom results of a preceding ultrasound examination were documented, review of ultrasound findings and final histological diagnosis was carried out. RESULTS: There were 155 cases with a reviewed histological diagnosis of complete or partial hydatidiform mole. In 131 (67%) cases, the sonographic diagnosis was that of a missed miscarriage/anembryonic pregnancy with no documented suspicion of molar pregnancy, referral being on the basis of histological examination of products of conception. In 63 cases, ultrasound examination suggested molar pregnancy; in 53 (84%) of these, the diagnosis of molar pregnancy was correct. Overall, 37 of 64 (58%) complete moles had sonographic evidence of molar pregnancy compared to 16 of 91 (17%) partial moles. Of 155 histologically confirmed complete or partial hydatidiform moles, only 53 (34%) were suspected as molar sonographically. CONCLUSION: The majority of cases of molar pregnancy now present as missed miscarriage/anembryonic pregnancy sonographically, highlighting the importance of histological examination to diagnose gestational trophoblastic disease.

Abortion, Missed↗
PubMed2000

Choriocarcinoma and partial hydatidiform moles.

BACKGROUND: Partial hydatidiform moles (PMs) rarely require chemotherapy and have never previously been proven to transform into choriocarcinoma, the most malignant form of gestational trophoblastic disease (GTD). Consequently, some have questioned whether women with PMs need human chorionic gonadotropin (hCG) follow-up. Here, we investigate whether PMs can transform into choriocarcinomas. METHODS: Patients with a PM who developed a subsequent choriocarcinoma were identified from our GTD database. The histology of both PM and ensuing choriocarcinoma was reviewed and flow cytometry used to verify the triploid status of the PMs. To determine whether the choriocarcinoma arose from the PM, DNA from the PM and choriocarcinoma in each patient was compared using microsatellite polymorphisms. FINDINGS: Of the 3000 patients with PM, 15 required chemotherapy for persisting GTD. This was identified as choriocarcinoma in three cases. In one patient, the local pathologist could not differentiate between a PM or a hydropic abortion and neither central histological review nor hCG follow-up were obtained. This patient nearly died before the diagnosis of choriocarcinoma was made. Fortunately, the local pathologists correctly diagnosed PM in the two other patients who were then registered for hCG follow-up. Some months later, the hCG was rising and repeat uterine evacuation revealed choriocarcinoma. The PM was confirmed to be triploid in all three cases and genetic analysis showed that the subsequent choriocarcinomas contained identical single maternal and two paternal alleles at several independent loci. INTERPRETATION: Our results show that PMs can transform into choriocarcinoma. All patients with suspected PM should be reviewed centrally and, if confirmed, need hCG follow-up.

Adult↗
PubMed2000

Safety of multiple daily applications of COL-1492, a nonoxynol-9 vaginal gel, among female sex workers. COL-1492 Phase II Study Group.

RATIONALE: COL-1492 is a nonoxynol-9 (N-9)-containing vaginal gel and may be a potential microbicide. As part of an effectiveness trial, an initial toxicity study was conducted. OBJECTIVES: The main objective of the reported study was the assessment of the toxicity of a 52.5 mg N-9 gel, COL-1492, when used a number of times each day by female sex workers. METHODS: This was a randomized, placebo-controlled triple-blinded trial among female sex workers. The participants were asked to use the product for each vaginal sexual act. At each monthly visit a gynaecological examination with sexually transmitted disease sampling and colposcopy was performed. Venous blood was drawn for syphilis and HIV serology. All women received intensive counselling on condom use. Male condoms and sexually transmitted disease treatment were given free of charge. RESULTS: Only blinded results on the colposcopic examinations are reported. The incidence of lesions with or without an epithelial disruption was low: 0.06 and 0.29, respectively, per 100 woman-days in group A; 0.09 and 0.26 respectively per 100 woman-days in group B. There was no significant difference between the two arms. CONCLUSION: The multiple daily use of COL-1492 by female sex workers did not show an increase of local toxicity over that of a placebo. Colposcopy was discontinued in the autumn of 1997 in accordance with a Data Safety Monitoring Board decision. In the currently ongoing effectiveness trial the assessment of the product's toxicity continues to be monitored by simple visual examination.

Administration, Intravaginal↗
PubMed2000

Major chemical incidents: bridging the occupational--public health gap.

Increasing awareness and concern about possible long-term health effects of exposure to chemicals after major chemical incidents has opened up a new area of public health activity. However, progress is hampered by a lack of low level exposures in potentially highly susceptible subgroups of the populations, and by a lack of expertise in public health. The challenge is to extend the toxicological and epidemiological experience developed in the occupational setting to the community level. To better define the problem population surveillance of acute chemical hazards, first set up in Wales, has been extended throughout the UK, and is also being piloted internationally. Further work is needed to address specific problems of the epidemiological follow-up of populations exposed, the assessment of the psychological consequences at the community level, and risk perception and communication. Organisational arrangements for the public health management of incidents and their sequelae must move beyond short-term funding and market competition and must incorporate the expertise of the occupational disciplines.

Chemical Industry↗
PubMed2000

Investigation of an acute chemical incident: exposure to fluorinated hydrocarbons.

OBJECTIVES: To assess whether attendance at the site after an incident in a sewer was associated with symptoms in emergency personnel and whether the prevalence of symptoms was associated with estimated levels of exposure to any chemical hazard. METHODS: Symptoms experienced by people attending an incident involving two dead sewer workers suggested the presence of a chemical hazard, before environmental sampling confirmed any toxic agent. Self reported symptoms, estimated exposures, and biomarkers of exposure for likely agents from all 254 people who attended the incident and a referent occupational group matching the 83 emergency personnel who went to the Accident and Emergency department (A and E) in the first 48 hours were recorded. The prevalence of symptoms and concentrations of creatine phosphokinase in serum of the 83 early patients at A and E were compared with their referent occupational group. In all workers who attended the incident, the trends in symptom prevalences and concentrations of creatine phosphokinase in serum were examined by distance from the site and predefined exposure category. RESULTS: Among all workers who attended the incident, symptoms of shortness of breath and sore throat were significantly associated with indirect estimates of exposure but not associated with concentrations of creatine phosphokinase. Freon was detected in two blood samples. The early patients at A and E reported more symptoms than their matched reference group and their median concentrations of creatine phosphokinase were higher. CONCLUSIONS: The association between symptoms and concentrations of creatine phosphokinase with attendance at the site indicated the presence of a continuing hazard at the site and led to extra precautions being taken. Comparison values from the referent occupational group prevented unnecessary medical follow up.

Adult↗
PubMed2000

A CAT-derived one to three session intervention for repeated deliberate self-harm: a description of the model and initial experience of trainee psychiatrists in using it.

We describe a new Cognitive Analytic Therapy (CAT)-based intervention for those who repeatedly self-harm. It is specifically designed to be deliverable by staff with no training in psychotherapy. The intervention is simply manualized into sequential tasks that are mediated by new CAT-style standardized tools. A particular feature of this intervention is the deliberate use of feelings elicited in the therapist ('counter-transference') as (a) a guide to how professional poise is being threatened or lost and (b) an indicator of the appropriate focus for this very brief therapy. The psychiatrists' reflection on their elicited feelings is mediated by a new CAT tool, the 'Assessor's Response File' developed in this project. Audiotape analysis suggested that following a very brief learning period, trainee psychiatrists were able to adhere to the structure of the model and arrive at an appropriate reformulation in the first session but tended to be collusive in reciprocating the patients' dysfunctional coping styles.

Adaptation, Psychological↗
PubMed2000

Randomised controlled trial of the efficacy of misoprostol used as a cervical ripening agent prior to termination of pregnancy in the first trimester.

BACKGROUND: Misoprostol is being used increasingly in clinical practice for cervical ripening in first-trimester abortions, but because of lack of good evidence of its effectiveness, administration consensus has not been reached on dosage, route of administration, time of administration pre-operatively and gestational age group. In this study we tested the hypothesis that self-administration of 600 micrograms vaginal misoprostol is feasible and when used 2-4 hours pre-operatively results in sufficient cervical dilatation to make suction curettage easier. METHODS: A double-blind, randomised, placebo-controlled trial was undertaken. Two hundred and seventy-eight women scheduled for termination of pregnancy of up to 12 weeks' duration by manual vacuum aspiration were assigned to receive either 600 micrograms misoprostol pre-operatively, or placebo. The achievement of 'satisfactory' (> or = 7 mm) baseline cervical dilatation after 2-4 hours was evaluated as the primary outcome. Secondary outcome measurements included ease and duration of the procedure. Side-effects such as pre-operative bleeding, gastro-intestinal complaints and pain as well as adverse events were noted in all cases. FINDINGS: Self-administration of vaginal misoprostol was successful in all women and 273 women were evaluated for main end-points. A significantly larger proportion of patients in the treatment group reached cervical dilatation of > or = 7 mm (67.3% v. 30.9%, P < 0.0001). The side-effects were minimal and comparable in the two groups. In the treatment group the mean procedure duration was significantly shorter (220 seconds v. 321 seconds, P = 0.0013) and the procedure was more likely to be rated by the operator as 'easy' (81.8% v. 63.3%, P = 0.0082). This resulted in a significant reduction in treatment failure in the < 70-day gestation group (5.0% v. 14.7%, P = 0.005). CONCLUSION: It is feasible, safe and effective for 600 micrograms misoprostol to be self-administered vaginally 2-4 hours pre-operatively for cervical priming prior to manual vacuum aspiration. Further research is needed to establish optimal use in the first trimester and to determine patient acceptance.

Abortifacient Agents, Nonsteroidal↗
PubMed1999

A fatal case of autoimmune thrombocytopenia with an IgM anti-GPIb/IX following one antigen mismatched unrelated donor bone marrow transplantation.

We report the case of a 32-year-old patient with ALL who developed autoimmune thrombocytopenia 2 months following allogeneic bone marrow transplantation. An IgM autoantibody against the platelet glycoprotein Ib/IX complex was observed. Treatment with high-dose steroids and intravenous immunoglobulin G failed to produce any benefit and the thrombocytopenia led to fatal gastrointestinal haemorrhage. The possible factors contributing to post-allograft thrombocytopenia and potential management strategies are discussed.

Adult↗