Identification of a possible biomarker for colophony exposure

Colophony is known to cause occupational asthma and dermatitis. Biological monitoring may be useful in assessing exposure. This paper describes a method for the analysis of dehydroabietic acid in urine and its potential use as a marker of colophony exposure. The method involves hydrolysis, solvent extraction, derivatization and analysis by gas chromatography-mass spectrometry. Twenty-eight workers from a soldering factory in South Africa were monitored. Results showed that levels of dehydroabietic acid in urine may be correlated with a subjective assessment of exposure.

Frontal lobe function, sleep loss and fragmented sleep

Recent experimental studies involving total sleep loss, sleep reduction and clinically related sleep fragmentation report impaired performance on tasks of frontal lobe or executive function, including measures of verbal fluency, creativity and planning skills. Severity of sleep disturbance in obstructive sleep apnoea syndrome (OSAS) is correlated with level of executive impairment, with some residual impairment despite treatment (continuous positive airway pressure - CPAP). Executive impairment appears to be more closely related to hypoxaemic events rather than daytime sleepiness. Studies of electroencephalographic (EEG) changes throughout the course of sleep and following sleep deprivation as well as functional neuroimaging and psychophysiological changes (event-related potentials - ERPs) following sleep deprivation provide further indication of the relative importance of the frontal regions of the brain to sleep. However, neurocognitive studies present many inconsistencies, task classification is often ambiguous and, in the absence of any unifying explanation at the level of cognitive mechanisms, the overall picture is one of a disparate range of impairment following sleep loss and sleep fragmentation. Poorly defined concepts of frontal lobe function, executive function, memory and attention, using tasks largely developed with more severe deficit levels in mind, create further difficulties in interpreting current findings.

Characterization of surface antigen from Lyme disease spirochete Borrelia burgdorferi

Borrelia burgdorferi, the Lyme disease spirochete, possesses a surface protein, VlsE (variable major protein-like sequence, expressed), that undergoes antigenic variation. Unlike conserved regions of other proteins involved in antigenic variation, the most conserved invariable region of VlsE is immunodominant in Lyme-disease patients. Physicochemical analyses of pure recombinant VlsE yielded the following results: The protein appeared oligomeric in solution, with a secondary structure dominated by alpha-helices. Thermal denaturation (pH 7) probed by calorimetry involved two transitions: oligomer-to-monomer conversion (around 40 degrees C) followed by protein unfolding (55 +/- 1 degrees C). Chemical denaturation monitored by far-UV circular dichroism (20 degrees C, pH 7) sensed only polypeptide unfolding and took place in a single transition (Delta G(U)(H(2)O) = 23 +/- 2 kJ/mol). VlsE did not adopt a native structure at pH 3; at pH 10 the stability was significantly reduced. Knowledge of biophysical properties of VlsE may aid in understanding the mechanism of VlsE antigenic variation in B. burgdorferi.

Correlates of clinic referral for early conduct problems: variable- and person-oriented approaches

The current study utilized both variable- and person-oriented analyses to examine correlates of early disruptive behavior problems. Participants included 80 preschool boys referred to a child psychiatry clinic and diagnosed with oppositional defiant disorder (with or without attention-deficit hyperactivity disorder) and 80 case-matched normal comparison boys. The study examined four domains of correlates: vulnerable child characteristics, poor parenting practices, insecure attachment, and adverse family ecology. Results indicated that the combination of these factors provided relatively high sensitivity (81%) and specificity (85%), clearly differentiating referred from comparison boys. A dramatic increase in clinic status occurred when three or more factors were present, and specific combinations of factors were differentially predictive of conduct problems. However, no correlates were found to be either necessary or sufficient for clinic status. By maintaining the integrity of individual cases, person-oriented analyses were able to answer different questions than more traditional variable-oriented analyses. Discussion focuses on the value of person-oriented analyses for understanding heterogeneous clinical groups.

The implementation of venous leg ulcer guidelines: process analysis of the intervention used in a multi-centre, pragmatic, randomized, controlled trial

The production and implementation of clinical practice guidelines is currently a high political priority and a rapidly developing field within healthcare in the United Kingdom (UK). Their purpose is to provide clinicians with a synthesis of the best available external evidence and operationalize the implementation of evidence-based practice. Despite indications that clinical guidelines can make a difference to the quality of patient care, there is some evidence that practitioners struggle with their application. The aim of this paper is to report one element of a trial undertaken by three collaborating universities in the Northern and Yorkshire Region of the UK health service during 1997-1998. The objective was to understand what makes guidelines acceptable and usable, or otherwise, to health professionals. The findings reported in this paper describe the process of care in those general practices that elected to implement guidelines for the management of patients with venous leg ulcers. We conclude that planning for training, resource and quality improvement processes must be built into a team's guidelines implementation procedures. A preliminary needs analysis of the contextual 'hurdles and levers' within each primary healthcare team is also necessary to identify individual issues that must be addressed if the process is to succeed. These findings provide some lessons for successful implementation of clinical guidelines in general. Recommendations for nursing policy makers, managers, practitioners and researchers are included.

Effectiveness of optometrist screening for diabetic retinopathy using slit-lamp biomicroscopy

PURPOSE

To assess the effectiveness of optometrists as screeners for diabetic retinopathy using slit-lamp binocular indirect ophthalmoscopy through dilated pupils.

METHODS

Prospective study of a screening scheme. Screening was performed by 27 locally accredited optometrists in their practice. The referral protocol used a new simple grading system of retinopathy, especially designed for use in an optometrist screening programme. All positive referrals and 10% of negative referrals were reexamined by an ophthalmologist. Sensitivity, specificity, likelihood ratios and technical failure rates were calculated.

RESULTS

The optometrists screened 4904 people with diabetes in 18 months. 'Subthreshold' (screen negative) reports accounted for 4438 (90.5% of 4904); 429 (9.67%) of these were re-examined at secondary screening. There was disagreement regarding grading in 13 patients, of whom 5 (1.16% of 429) had sight-threatening retinopathy (STDR); this extrapolates to 52 patients if all the 4438 test-negatives had been examined. Of the 371 'threshold' patients, 112 (30.18%) were false positives; the commonest cause for false positive referral was drusen in patients with background diabetic retinopathy. The sensitivity for identification of STDR was 76% (95% CI 70% to 81%) and specificity 95% (95% CI 95% to 96%). The likelihood ratio of a positive test indicating STDR was 16.54 (95% CI 14.17 to 19.23) and that of a negative test 0.25 (95% CI 0.20 to 0.32). The technical failure rate was 0.2%.

CONCLUSIONS

Suitably trained and accredited community optometrists performed well when screening for diabetic retinopathy using slit-lamp biomicroscopy through a dilated pupil. This was facilitated by the use of simple grading and referral criteria. The sensitivity, positive likelihood ratio and specificity were high.

Prevalence of blindness and visual impairment in a population of people with diabetes

PURPOSE

To assess the prevalence of visual impairment and the underlying causes in a population of people with diabetes.

METHOD

A population-based study of a defined population of people with diabetes in a district in the North West of England was done. There were 7652 known people with diabetes, representing 2.12% of target general population of 361050. The main outcome measures were the prevalence of blindness and significant visual impairment (less than 6/18 corrected vision in their better eye) and the underlying causes.

RESULTS

Visual acuity data on 6482 (84.7%) of the 7652 individuals were obtained. Of these, 184 had significant visual impairment (prevalence 2.84%) including 49 who were blind (vision of less than 3/60 in their better eye, prevalence 0.75%); if blindness was defined as vision less than or equal to 6/60, prevalence was 1.13% (n = 73). Details of 3 individuals could not be ascertained. Only 67 were registered, either as partially sighted (n = 42) or as blind (n = 25). In the majority (n = 133; 68%) of these 181 individuals the visual impairment was due to causes other than diabetic retinopathy.

CONCLUSIONS

The prevalence of blindness and visual impairment in our population of people with diabetes was low. Non-diabetic eye disease accounted for the majority of this visual impairment. This provides essential baseline data against which future progress can be assessed. Screening and treatment can greatly reduce the incidence of visual impairment due to diabetic retinopathy, but its impact on overall visual impairment rates in the population of people with diabetes will be more modest.

An economic evaluation of community water fluoridation

OBJECTIVE

The purpose of this research was to assess the local cost savings resulting from community water fluoridation, given current exposure levels to other fluoride sources.

METHODS

Adopting a societal perspective and using a discount rate of 4 percent, we compared the annual per person cost of fluoridation with the cost of averted disease and productivity losses. The latter was the product of annual dental caries increment in nonfluoridated communities, fluoridation effectiveness, and the discounted lifetime cost of treating a carious tooth surface. We obtained or imputed all parameters from published studies and national surveys. We conducted one-way and three-way sensitivity analyses.

RESULTS

With base-case assumptions, the annual per person cost savings resulting from fluoridation ranged from $15.95 in very small communities to $18.62 in large communities. Fluoridation was still cost saving for communities of any size if we allowed increment, effectiveness, or the discount rate to take on their worst-case values, individually. For simultaneous variation of variables, fluoridation was cost saving for all but very small communities. There, fluoridation was cost saving if the reduction in carious surfaces attributable to one year of fluoridation was at least 0.046.

CONCLUSION

On the basis of the most current data available on the effectiveness and cost of fluoridation, caries increment, and the cost and longevity of dental restorations, we find that water fluoridation offers significant cost savings.

Efficacy, safety, and use of ginkgo biloba in clinical and preclinical applications

Ginkgo biloba is a dioecious tree with a history of use in traditional Chinese medicine. Although the seeds are most commonly employed in traditional Chinese medicine, in recent years standardized extracts of the leaves have been widely sold as a phytomedicine in Europe and as a dietary supplement in the United States. The primary active constituents of the leaves include flavonoid glycosides and unique diterpenes known as ginkgolides; the latter are potent inhibitors of platelet activating factor. Clinical studies have shown that ginkgo extracts exhibit therapeutic activity in a variety of disorders including Alzheimer's disease, failing memory, age-related dementias, poor cerebral and ocular blood flow, congestive symptoms of premenstrual syndrome, and the prevention of altitude sickness. Due in part to its potent antioxidant properties and ability to enhance peripheral and cerebral circulation, ginkgo's primary application lies in the treatment of cerebrovascular dysfunctions and peripheral vascular disorders.

The effects of varying resistance-training loads on intermediate- and high-velocity-specific adaptations

The purpose of this study was to compare changes in velocity-specific adaptations in moderately resistance-trained athletes who trained with either low or high resistances. The study used tests of sport-specific skills across an intermediate- to high-velocity spectrum. Thirty NCAA Division I baseball players were randomly assigned to either a low-resistance (40-60% 1 repetition maximum [1RM]) training group or a high-resistance (70-90% 1RM) training group. Both of the training groups intended to maximallv accelerate each repetition during the concentric phase (IMCA). The 10 weeks of training consisted of 4 training sessions a week using basic core exercises. Peak force, velocity, and power were evaluated during set angle and depth jumps as well as weighted jumps using 30 and 50% 1RM. Squat 1RMs were also tested. Although no interactions for any of the jump tests were found, trends supported the hypothesis of velocity-specific training. Percentage gains suggest that the combined use of heavier training loads (70-90% 1RM) and IMCA tend to increase peak force in the lower-body leg and hip extensors. Trends also show that the combined use of lighter training loads (40-60% 1RM) and IMCA tend to increase peak power and peak velocity in the lower-body leg and hip extensors. The high-resistance group improved squats more than the low-resistance group (p < 0.05; +22.7 vs. + 16.1 kg). The results of this study support the use of a combination of heavier training loads and IMCA to increase 1RM strength in the lower bodies of resistance-trained athletes.

Transgenic mice with cardiac-specific expression of activating transcription factor 3, a stress-inducible gene, have conduction abnormalities and contractile dysfunction

Activating transcription factor 3 (ATF3) is a member of the CREB/ATF family of transcription factors. Previously, we demonstrated that the expression of the ATF3 gene is induced by many stress signals. In this report, we demonstrate that expression of ATF3 is induced by cardiac ischemia coupled with reperfusion (ischemia-reperfusion) in both cultured cells and an animal model. Transgenic mice expressing ATF3 under the control of the alpha-myosin heavy chain promoter have atrial enlargement, and atrial and ventricular hypertrophy. Microscopic examination showed myocyte degeneration and fibrosis. Functionally, the transgenic heart has reduced contractility and aberrant conduction. Interestingly, expression of sorcin, a gene whose product inhibits the release of calcium from sarcoplasmic reticulum, is increased in these transgenic hearts. Taken together, our results indicate that expression of ATF3, a stress-inducible gene, in the heart leads to altered gene expression and impaired cardiac function.

A study of inter-arm blood pressure differences in primary care

OBJECTIVES

To investigate whether there are inter-arm blood pressure differences that are of clinical importance to general practice.

DESIGN AND SETTING

Pragmatic study with randomised order of use of left or right arm carried out in routine surgeries in an inner city and suburban general practice.

SUBJECTS

There were 237 patients presenting opportunistically for blood pressure measurement to a nurse or general practitioner.

MAIN OUTCOME MEASURES

95% limits of agreement between measurements on the left and right arm and bias between arms.

RESULTS

Large inter-arm blood pressure differences exist reflected in wide 95% limits of agreement; -16 mm Hg to 24 mm Hg for the right minus the left arm diastolic blood pressure. There is a small but statistically significant bias to the right arm blood pressure measuring higher than the left (3.7 mm Hg diastolic, 2.4 to 5 mm Hg 95% confidence intervals). An interarm difference of 10 mm Hg or greater for diastolic blood pressure occurred in 40% of subjects and a difference of 20 mm Hg or more for systolic blood pressure occurred in 23% of subjects.

CONCLUSIONS

In a primary care setting blood pressure should be measured routinely in both arms. If one arm is to be preferred for pragmatic clinical purposes, then this should be the right arm.

Comparing sports injuries in men and women

OBJECTIVE

To compare the pattern of injury between men and women in seven collegiate sports to determine if gender-specific factors exist which could be modified to reduce the risk of injury to female athletes.

DESIGN

Retrospective cohort study of injury reports compiled by certified athletic trainers between Fall 1980 and Spring 1995.

SETTING

An NCAA division III College.

PARTICIPANTS

Eighteen to 22 year-old male and female college athletes competing in seven like sports (basketball, cross-country running, soccer, swimming, tennis, track and water polo) at the intercollegiate level, playing similar number of contests and using the same facilities.

MAIN OUTCOME MEASURES

Analyses of injury patterns, classified by sport and anatomic location, for men and women in seven like sports.

RESULTS

A total of 3,767 participants were included in the study, with 1874 sports-related injuries reported among the men and women's teams. Of these injuries, 856 (45.7%) were sustained by female and 1018 (54.3%) by male athletes. Overall, no statistically significant gender difference was found for injuries per 100 participant-years (52.5 for female athlete versus 47.7 for males). A statistically significant gender difference in injury incidence (p < 0.001) was seen for two sports: swimming and water polo. Female swimmers reported more back/neck, shoulder, hip, knee and foot injuries: and female water polo players reported more shoulder injuries. When evaluating all sports concurrently, female athletes reported a higher rate of hip, lower-leg and shoulder injuries, while male athletes reported a higher rate of thigh injuries.

CONCLUSION

Except for some minor gender differences in total injuries for two sports and several differences in total injuries by anatomic location, our data suggest very little difference in the pattern of injury between men and women competing in comparable sports. The increased rate of shoulder injury among female swimmers probably resulted from the more rigorous training philosophy of their coach. Thus, no gender-specific recommendations can be suggested for decreasing the incidence of injury to female athletes competing in these sports.

P-Glycoprotein and transporter MRP1 reduce HIV protease inhibitor uptake in CD4 cells: potential for accelerated viral drug resistance?

BACKGROUND

The multidrug transporters P-glycoprotein (P-gp) and MRP1 are functionally expressed in several subclasses of lymphocytes. HIV-1 protease inhibitors interact with both; consequently the transporters could reduce the local concentration of HIV-1 protease inhibitors and, thus, influence the selection of viral mutants.

OBJECTIVES

To study the effect of the expression of P-gp and MRP1 on the transport and accumulation of HIV-1 protease inhibitors in human lymphocytes and to study the effects of specific P-gp and MRP1 inhibitors.

METHODS

The initial rate and the steady-state intracellular accumulation of radiolabelled ritonavir, indinavir, saquinavir and nelfinavir was measured in three human lymphocyte cell lines: control CEM cells, CEM-MDR cells, which express 30-fold more P-gp than CEM cells, and CEM-MRP cells, which express fivefold more MRP1 protein than CEM cells. The effect of specific inhibitors of P-gp (GF 120918) and MRP1 (MK 571) was also examined.

RESULTS

Compared with CEM cells, the initial rates of uptake and the steady-state intracellular concentrations of all protease inhibitors are significantly reduced in CEM-MDR cells. The intracellular concentrations of the protease inhibitors are increased upon co-administration with GF 120918, in some cases to levels approaching those in CEM cells. The intracellular concentrations of the protease inhibitors are also significantly reduced in CEM-MRP cells. Co-administration with MK -571 can partially overcome these effects.

CONCLUSIONS

The overexpression of multidrug transporters significantly reduces the accumulation of protease inhibitors at this major site of virus replication, which, potentially, could accelerate the acquisition of viral resistance. Targeted inhibition of P-gp may represent an important strategy by which this problem can be overcome.

C-cell and thyroid epithelial tumours and altered follicular development in transgenic mice expressing the long isoform of MEN 2A RET

Gain-of-function mutations in the gene encoding the receptor tyrosine kinase RET have been identified as the aetiological factor for multiple endocrine neoplasia type 2A (MEN2A). MEN2A is a dominantly-inherited cancer predisposition syndrome characterized by medullary thyroid carcinoma, a tumour of the calcitonin-producing thyroid C-cells. There are three isoforms of RET: RET9, RET43 and RET51, and although in vitro evidence suggests they vary in cellular transformation activities, little is known about their function in tumorigenesis in vivo. To address this, we used RET51 cDNA to construct mice in which the most frequent MEN2A mutation, Cys-634-Arg, was expressed under the control of the human calcitonin promoter (CT-2A mice). These mice developed C-cell tumours resembling human MTC and follicular tumours resembling human papillary thyroid carcinoma (PTC) depending on the founder line examined. One founder line developed compound MTC/PTC at low frequency (8%) and pancreatic cystadenocarcinoma. CT-2A mice also displayed a developmental defect in thyroid follicular structure, in which much of the thyroid was occupied by large irregular cystic follicles thought to be derived from the ultimobranchial body, a developmental precursor of the thyroid gland. The CT-2A mice will provide a suitable model to further study the effects of the MEN 2A RET mutation in vivo.

Endometrial laser intrauterine thermotherapy for the treatment of dysfunctional uterine bleeding: the first British experience

Forty patients due to undergo endometrial ablation as a treatment for dysfunctional uterine bleeding were recruited to assess the efficacy and safety of endometrial laser intrauterine thermo-therapy using the gynelase. At 12 months the average menstrual score reduction was 88%, the amenorrhoea rate was 70%, and the hypomenorrhoea rate 16%. Four women (10%) have had a hysterectomy for persistent menorrhagia, and one (3%) for pelvic pain. One patient (3%) has had a further endometrial laser ablation. There were no major complications. and 34 patients (85%) were most satisfied with the treatment. The system is easy to use and has a short learning curve.

Preclinical prediction of AD using neuropsychological tests

Normals (N = 42) and patients with mild memory difficulty (N = 123) were given a neuropsychological test battery, and then followed annually for 3 years to determine which individuals developed sufficient functional change that they met clinical criteria for AD. Twenty-three of the 123 participants with mild memory difficulty converted to a diagnosis of probable Alzheimer's disease (AD) within 3 years of follow-up. Four of the 20 neuropsychological measures obtained at baseline, were useful in discriminating the groups on the basis of their status 3 years after the tests were given. The 4 discriminating tests pertained to assessments of memory and executive function. When the controls were compared to the individuals with memory impairments who ultimately developed AD (the converters), the accuracy of discrimination was 89%, based on the neuropsychological measures at baseline. The discrimination of the controls from the individuals with mild memory problems who did not progress to the point where they met clinical criteria for probable AD over the 3 years of follow-up (the Questionables) was 74% and the discrimination of the questionables from the converters was 80%. The specific tests that contributed to these discriminations, in conjunction with recent neuropathological and neuroimaging data from preclinical cases, have implications for which brain regions may be affected during the prodromal phase of AD.

Presenilin-1-associated abnormalities in regional cerebral perfusion

OBJECTIVE

To investigate the influence of the presenilin-1 gene (PS-1) mutation on regional cerebral perfusion, SPECT was evaluated in 57 individuals. The subjects were members of a large pedigree from Colombia, South America, many of whom carry a PS-1 mutation for early-onset AD.

METHODS

Members of this large kindred who were cognitively normal and did not carry the PS-1 mutation (n = 23) were compared with subjects who were carriers of the mutation but were asymptomatic (n = 18) and with individuals with the mutation and a clinical diagnosis of AD (n = 16). Cerebral perfusion was measured in each subject using hexamethylpropyleneamine oxime SPECT. The data were analyzed in two ways: 1) Mean cerebral perfusion in each of 4320 voxels in the brain was compared among the groups using t-tests (t-maps); and 2) each individual received a weighted score on 20 vectors (factors), based on a large normative sample (n = 200), using a method known as singular value decomposition (SVD).

RESULTS

Based on t-maps, subjects with the PS-1 mutation who were asymptomatic demonstrated reduced perfusion in comparison with the normal control subjects in the hippocampal complex, anterior and posterior cingulate, posterior parietal lobe, and anterior frontal lobe. The AD patients demonstrated decreased perfusion in the posterior parietal and superior frontal cortex in comparison with the normal control subjects. Discriminant function analysis of the vector scores derived from SVD (adjusted for age and gender) accurately discriminated 86% of the subjects in the three groups (p < 0.0005).

CONCLUSION

Regional cerebral perfusion abnormalities based on SPECT are detectable before development of the clinical symptoms of AD in carriers of the PS-1 mutation.

The feasibility of a 'one stop' ultrasound-based clinic for the diagnosis and management of abnormal uterine bleeding

OBJECTIVES

We have established a 'one stop' clinic for the management of women with abnormal uterine bleeding based on transvaginal sonography and saline contrast sonohysterography. This report reviews our experience with the first 93 patients attending the clinic.

DESIGN AND METHODS

Patients were seen with the intention of performing a transvaginal scan, saline contrast sonohysterography, endometrial biopsy, full blood count and thyroid function tests. The findings were prospectively recorded on a computer database and a management plan formulated.

RESULTS

A transvaginal scan was performed on 89 (95.7%) women, 70 (75.3%) also undergoing saline contrast sonohysterography. An endometrial biopsy was carried out in 67 (72%) women aged 40 years and above, and 79 (84.9%) had blood tests. The median age of patients was 44 (range, 21-78) years. The majority of women presented with menstrual disorders. Uterine pathology was detected on transvaginal scan in 42 (47.2%) cases. Adnexal pathology was detected in 12 (13.5%) of the patients. Endometrial biopsy detected three (4.5%) cases of endometrial atypia, and three (4.5%) cases of adenocarcinoma. A hemoglobin level of < 10 g/dL was detected in 3 (3.4%) patients. A single clinic visit was thought sufficient for 83 (89.2%) women. Medical therapy was started in 47 (50.5%) patients, 15 (16.3%) were brought back for inpatient diagnostic hysteroscopy, and nine (9.7%) were booked for operative endoscopy, while six (6.5%) had conventional surgery; the remainder were reassured.

CONCLUSIONS

This study demonstrates that a 'one stop' management philosophy based on pelvic ultrasound is feasible. Our data suggest that diagnostic hysteroscopy can be decreased using this approach, and challenge the use of hysteroscopy as the first stage test.

Effect of rodent diets on the sexual development of the rat

Five rodent diets have been evaluated for their possible effect on the sexual development of the rat. Groups of 12 pregnant Alpk rats were fed one of the following combinations of diets during pregnancy and postnatally: RM3/RM1, AIN-76A/AIN-76A, RM3/AIN-76A, Teklad Global 2016 (Global)/Global and Purina 5001/Purina 5001. AIN-76A is phytoestrogen-free while the other diets contained varying amounts of phytoestrogens. The phytoestrogens genistein and daidzein were determined in the diets studied, and the concentrations found agreed with earlier estimates. RM3/RM1 was selected as the control group, as this has been used routinely in this laboratory for the past decade. Determinations were made in offspring of the times of vaginal opening and first estrus among the females, and of prepuce separation and testes descent among the males. At postnatal day (PND) 26 the females from 6 of the 12 litters were terminated and tissue weights measured. Males from 6 of the 12 litters were similarly studied at PND 68. Animals from the remaining litters were transferred to RM1 diet at PND 70. Termination of the study was at PND 128 (males) and PND 140 (females) when body weights and tissue weights were determined. Marked differences in body weight, sexual development, and reproductive tissue weights were observed for rats maintained on AIN-76A or Purina 5001, with only minimal effects among rats maintained on the Global diet. These comparisons were against RM3/RM1 as the reference diet. However, using Purina 5001 as the reference diet reversed the direction of the differences seen when using RM3/RM1 as the reference diet. The differences observed when using RM3/RM1 as reference diet occurred mainly postnatally. In addition, the fact that similar differences were seen for the phytoestrogen-free diet, AIN-76A, and the phytoestrogen-rich diet, Purina 5001, indicate that these effects are more likely to be caused by nutritional differences between the diets that then have centrally mediated effects on rodent sexual development, rather than individual dietary components affecting peripheral estrogen receptors (ER). This proposal is supported by abolition of the uterotrophic activity of AIN-76A and Purina 5001 (relative to RM3/RM1) in the immature rat by coadministration of the gonadotrophin-releasing hormone (GnRH) antagonist ANTARELIX: The present data indicate that choice of diet may influence the timing of sexual development in the rat, and consequently, that when evaluating the potential endocrine toxicity of chemicals, the components of rodent diets used should be known, and as far as is possible, controlled.

Black cohosh: efficacy, safety, and use in clinical and preclinical applications

Actaea racemosa L (formerly Cimicifuga racemosa [L] Nutt) (Ranunculaceae), commonly known as black cohosh, is an herb native to Eastern North America. Black cohosh has a history of traditional use among Native Americans for the treatment of a variety of disorders, including various conditions unique to women such as amenorrhea and menopause. Contemporary uses of black cohosh are primarily geared toward the treatment of symptoms of menopause, such as hot flashes, and menopausal anxiety and depression. Extracts also have been shown to be useful for younger women suffering hormonal deficits following ovariectomy or hysterectomy, as well as for juvenile menstrual disorders. A number of clinical studies using Remifemin, a standardized extract, have demonstrated efficacy for the alleviation of menopausal complaints. The safety profile of black cohosh is positive, with low toxicity, few and mild side effects, and good tolerability. In European phytotherapy, Remifemin is commonly prescribed as an effective alternative to hormone replacement therapy for menopause.