Serum CA125 and HE4 as Biomarkers for the Detection of Endometrial Cancer and Associated High-Risk Features

Early detection of endometrial cancer improves survival. Non-invasive diagnostic biomarkers would improve triage of symptomatic women for investigations. This study aimed to determine the diagnostic accuracy of serum Cancer Antigen 125 (CA125) and Human Epididymis 4 (HE4) for endometrial cancer and associated high-risk features. Serum samples from women investigated for gynaecological symptoms or diagnosed with endometrial cancer were analysed for CA125 and HE4. Conventional diagnostic metrics were calculated. In total, 755 women were included; 397 had endometrial cancer. Serum CA125 and HE4 were significantly elevated in cases compared with controls (both p < 0.001), and with pathological markers of disease severity (p < 0.05). A combination of CA125 and HE4 detected endometrial cancer with an area under the curve (AUC) of 0.77 (95% CI: 0.74−0.81). In a model with body mass index (BMI) and parity, HE4 predicted endometrial cancer in pre-menopausal women with an AUC of 0.91 [sensitivity = 84.5%, specificity = 80.9% (p < 0.001)]. In women with abnormal ultrasound, HE4 ≥ 77 pmol/L improved specificity compared with imaging alone [68.6% (95% CI: 75.0−83.6) vs. 34.4% (95% CI: 27.1−42.3), respectively], but at a cost to sensitivity. HE4 ≥ 77 pmol/L improved the detection of myometrial invasion ≥50% in women with stage I disease compared with magnetic resonance imaging (MRI) alone [sensitivity = 100% (95% CI: 54.1−100)]. CA125 ≥ 35 U/mL did not add to imaging. HE4 is a good predictor of poor prognostic features which could assist staging investigations.

Synchronous uterine and bladder cancers detected in urine and vaginal samples by cytology

Novel diagnostics for uterine cancer are urgently needed to reduce the burden of invasive testing for the majority of healthy women with postmenopausal bleeding. We have previously shown that uterine cancer cells can be detected by cytology in urine and vaginal samples with high diagnostic accuracy. Here, we demonstrate its potential to distinguish malignant cells of different aetiologies in the same urogenital biofluid sample according to their distinctive morphology and immunoprofiles. Synchronous tumours of the urogenital tract are uncommon but can cause diagnostic confusion, delays and poor outcomes. A 79-year-old woman presented to accident and emergency with postmenopausal bleeding. Voided urine and Delphi screener-collected vaginal samples were assessed by cytology and immunocytochemistry. Two malignant cell populations with distinct morphology and immunophenotypes consistent with synchronous uterine and urothelial tumours were identified. Subsequent routine diagnostics confirmed concurrent uterine carcinosarcoma and high-grade urothelial carcinoma of the bladder. This case demonstrates that cytology and adjunctive immunocytochemistry can simultaneously identify and phenotype cancers of different aetiologies from a single urogenital biofluid sample. This can help rationalise diagnostic pathways in complex, unusual cases of dual urogenital primaries.

DEveloping Tests for Endometrial Cancer deTection (DETECT): protocol for a diagnostic accuracy study of urine and vaginal samples for the detection of endometrial cancer by cytology in women with postmenopausal bleeding

INTRODUCTION

Postmenopausal bleeding (PMB), the red flag symptom for endometrial cancer, triggers urgent investigation by transvaginal ultrasound scan, hysteroscopy and/or endometrial biopsy. These investigations are costly, invasive and often painful or distressing for women. In a pilot study, we found that voided urine and non-invasive vaginal samples from women with endometrial cancer contain malignant cells that can be identified by cytology. The aim of the DEveloping Tests for Endometrial Cancer deTection (DETECT) Study is to determine the diagnostic test accuracy of urine and vaginal cytology for endometrial cancer detection in women with PMB.

METHODS AND ANALYSIS

This is a multicentre diagnostic accuracy study of women referred to secondary care with PMB. Eligible women will be asked to provide a self-collected voided urine sample and a vaginal sample collected with a Delphi screener before routine clinical procedures. Pairs of specialist cytologists, blinded to participant cancer status, will assess and classify samples independently, with differences settled by consensus review or involving a third cytologist. Results will be compared with clinical outcomes from standard diagnostic tests. A sample size of 2000 women will have 80% power to establish a sensitivity of vaginal samples for endometrial cancer detection by cytology of ≥85%±7%, assuming 5% endometrial cancer prevalence. The primary objective is to determine the diagnostic accuracy of urogenital samples for endometrial cancer detection by cytology. Secondary objectives include the acceptability of urine and vaginal sampling to women.

ETHICS AND DISSEMINATION

This study has been approved by the North West-Greater Manchester West Research Ethics Committee (16/NW/0660) and the Health Research Authority. Results will be disseminated through publication in peer-reviewed scientific journals, presentation at conferences and via charity websites.

TRIAL REGISTRATION NUMBER

ISRCTN58863784.

Urinary Biomarkers and Their Potential for the Non-Invasive Detection of Endometrial Cancer

Endometrial cancer is the most common malignancy of the female genital tract and its incidence is rising in parallel with the mounting prevalence of obesity. Early diagnosis has great potential to improve outcomes as treatment can be curative, especially for early stage disease. Current tests and procedures for diagnosis are limited by insufficient accuracy in some and unacceptable levels of invasiveness and discomfort in others. There has, therefore, been a growing interest in the search for sensitive and specific biomarkers for endometrial cancer detection based on non-invasive sampling methodologies. Urine, the prototype non-invasive sample, is attractive for biomarker discovery as it is easily accessible and can be collected repeatedly and in quantity. Identification of urinary biomarkers for endometrial cancer detection relies on the excretion of systemic biomarkers by the kidneys or urinary contamination by biomarkers shed from the uterus. In this review, we present the current standing of the search for endometrial cancer urinary biomarkers based on cytology, genomic, transcriptomic, proteomic, and metabolomic platforms. We summarize the biomarker candidates and highlight the challenges inherent in urinary biomarker discovery. We review the various technologies with promise for biomarker detection and assess these novel approaches for endometrial cancer biomarker research.

Stiffness post-total knee replacement: A proof of principle study investigating the effect of gene expression analysis of markers of fibrosis

BACKGROUND

To establish proof of principle of a link between phenotypic expression and stiffness after TKR.

METHODS

From 100 patients, genetic expression of markers of fibrosis was performed for 15 synovial samples from patients categorised as 'best post-operative range of movement (ROM)' and 15 samples from patients with 'worst ROM'. These markers included Matrix Metalloproteinases (MMPs), A Disintegrin and Metalloproteinases with Thrombospondin (ADAMTS) and Tissue Inhibitors of Matrix Metalloproteinases (TIMPs). Genetic marker data were compared to Oxford Knee Scores (OKS) and Pain Catastrophizing Scores (PCS).

RESULTS

Quantitative markers for gene expression demonstrated more outliers in stiff compared to non-stiff knees, suggesting a greater imbalance in pro- and anti-fibrotic markers in stiff knees. Whilst there was a significant difference in the range of post-operative knee flexion (p = 0.001) and extension (p = 0.001), there was no statistically significant difference between stiff and non-stiff knees in pre-operative or post-operative OKS (p ≥ 0.06). There was no difference in the individual components of the individual PCS score items nor the PCS total scores when stiff and non-stiff knees were compared (p > 0.05).

CONCLUSION

Biological factors, namely gene expression of MMPs, TIMPs and ADAMTS, may contribute towards post-TKR stiffness. This now warrants further investigation to better understand this relationship based on larger, multi-centre, cohorts.

LEVEL OF EVIDENCE

Level 3.

An in vitro investigation into the effects of 10 Hz cyclic loading on tenocyte metabolism

Tendinopathy is a prevalent, highly debilitating condition, with poorly defined etiology. A wide range of clinical treatments has been proposed, with systematic reviews largely supporting shock wave therapy or eccentric exercise. Characterizing these treatments have demonstrated both generate perturbations within tendon at a frequency of approximately 8-12 Hz. Consequently, it is hypothesized that loading in this frequency range initiates increased anabolic tenocyte behavior, promoting tendon repair. The primary aim of this study was to investigate the effects of 10 Hz perturbations on tenocyte metabolism, comparing gene expression in response to a 10 Hz and 1 Hz loading profile. Tenocytes from healthy and tendinopathic human tendons were seeded into 3D collagen gels and subjected to 15 minutes cyclic strain at 10 Hz or 1 Hz. Tenocytes from healthy tendon showed increased expression of all analyzed genes in response to loading, with significantly increased expression of inflammatory and degradative genes with 10 Hz, relative to 1 Hz loading. By contrast, whilst the response of tenocytes from tendinopathy tendon also increased with 10 Hz loading, the overall response profile was more varied and less intense, possibly indicative of an altered healing response. Through inhibition of the pathway, IL1 was shown to be involved in the degradative and catabolic response of cells to high-frequency loading, abrogating the loading response. This study has demonstrated for the first time that loading at a frequency of 10 Hz may enhance the metabolic response of tenocytes by initiating an immediate degradatory and inflammatory cell response through the IL1 pathway, perhaps as an initial stage of tendon healing.

The stage of seed development influences iron bioavailability in pea (Pisum sativum L.)

Pea seeds are widely consumed in their immature form, known as garden peas and petit pois, mostly after preservation by freezing or canning. Mature dry peas are rich in iron in the form of ferritin, but little is known about the content, form or bioavailability of iron in immature stages of seed development. Using specific antibodies and in-gel iron staining, we show that ferritin loaded with iron accumulated gradually during seed development. Immunolocalization and high-resolution secondary ion mass spectrometry (NanoSIMS) revealed that iron-loaded ferritin was located at the surface of starch-containing plastids. Standard cooking procedures destabilized monomeric ferritin and the iron-loaded form. Iron uptake studies using Caco-2 cells showed that the iron in microwaved immature peas was more bioavailable than in boiled mature peas, despite similar levels of soluble iron in the digestates. By manipulating the levels of phytic acid in the digestates we demonstrate that phytic acid is the main inhibitor of iron uptake from mature peas in vitro. Taken together, our data show that immature peas and mature dry peas contain similar levels of ferritin-iron, which is destabilized during cooking. However, iron from immature peas is more bioavailable because of lower phytic acid levels compared to mature peas.

Wheat Vacuolar Iron Transporter TaVIT2 Transports Fe and Mn and Is Effective for Biofortification

Increasing the intrinsic nutritional quality of crops, known as biofortification, is viewed as a sustainable approach to alleviate micronutrient deficiencies. In particular, iron deficiency anemia is a major global health issue, but the iron content of staple crops such as wheat (Triticum aestivum) is difficult to change because of genetic complexity and homeostasis mechanisms. To identify target genes for the biofortification of wheat, we functionally characterized homologs of the VACUOLAR IRON TRANSPORTER (VIT). The wheat genome contains two VIT paralogs, TaVIT1 and TaVIT2, which have different expression patterns but are both low in the endosperm. TaVIT2, but not TaVIT1, was able to rescue the growth of a yeast (Saccharomyces cerevisiae) mutant defective in vacuolar iron transport. TaVIT2 also complemented a manganese transporter mutant but not a vacuolar zinc transporter mutant. By overexpressing TaVIT2 under the control of an endosperm-specific promoter, we achieved a greater than 2-fold increase in iron in white flour fractions, exceeding minimum legal fortification levels in countries such as the United Kingdom. The antinutrient phytate was not increased and the iron in the white flour fraction was bioavailable in vitro, suggesting that food products made from the biofortified flour could contribute to improved iron nutrition. The single-gene approach impacted minimally on plant growth and also was effective in barley (Hordeum vulgare). Our results show that by enhancing vacuolar iron transport in the endosperm, this essential micronutrient accumulated in this tissue, bypassing existing homeostatic mechanisms.

The genetics of an early Neolithic pastoralist from the Zagros, Iran

The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding, ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting those of the Central Zagros were somewhat isolated from other populations of the Fertile Crescent. Runs of homozygosity are of a similar length to those from Neolithic farmers, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.

MMP and TIMP temporal gene expression during osteocytogenesis

Osteocytes within bone differentiate from osteoblast precursors which reside in a mineralised extracellular matrix (ECM). Fully differentiated osteocytes are critical for bone development and function but the factors that regulate this differentiation process are unknown. The enzymes primarily responsible for ECM remodelling are matrix metalloproteinases (MMP); however, the expression and role of MMPs during osteocytogenesis is undefined. Here we used MLO-A5 cells to determine the temporal gene expressions of the MMP family and their endogenous inhibitors--tissue inhibitors of metalloproteinases (TIMPs) during osteocytogenesis. RT-qPCR revealed expression of 14 Mmps and 3 Timps in MLO-A5 cells. Mmp2, Mmp23 and Mmp28 were decreased concurrent with mineralisation onset (P < 0.05*). Mmp14 and Mmp19 mRNAs were also significantly increased at day 3 (P < 0.05*) before returning to baseline levels at day 6. Decreased expressions of Timp1, Timp2 and Timp3 mRNA were observed by day 6 compared to day 0 (P < 0.05*). To examine whether these changes are linked to osteocytogenesis, we determined Mmp/Timp mRNA expressions in mineralisation-limited conditions. RT-qPCR revealed that the previously observed decreases in Mmp2, Mmp23 and Mmp28 were not observed in these mineralisation-limited cultures, therefore closely linking these MMPs with osteocyte differentiation. Similarly, we found differential expression of Timp1, Timp2 and Timp3 mRNA in mineralisation-restricted cultures (P < 0.05*). In conclusion, we have identified several members of the MMP/TIMP families as regulators of ECM remodelling necessary for the acquisition of the osteocyte phenotype.

Are block copolymer worms more effective Pickering emulsifiers than block copolymer spheres?

RAFT-mediated polymerisation-induced self-assembly (PISA) is used to prepare six types of amphiphilic block copolymer nanoparticles which were subsequently evaluated as putative Pickering emulsifiers for the stabilisation of n-dodecane-in-water emulsions. It was found that linear poly(glycerol monomethacrylate)-poly(2-hydroxypropyl methacrylate) (PGMA-PHPMA) diblock copolymer spheres and worms do not survive the high shear homogenisation conditions used for emulsification. Stable emulsions are obtained, but the copolymer acts as a polymeric surfactant; individual chains rather than particles are adsorbed at the oil-water interface. Particle dissociation during emulsification is attributed to the weakly hydrophobic character of the PHPMA block. Covalent stabilisation of these copolymer spheres or worms can be readily achieved by addition of ethylene glycol dimethacrylate (EGDMA) during the PISA synthesis. TEM studies confirm that the resulting cross-linked spherical or worm-like nanoparticles survive emulsification and produce genuine Pickering emulsions. Alternatively, stabilisation can be achieved by either replacing or supplementing the PHPMA block with the more hydrophobic poly(benzyl methacrylate) (PBzMA). The resulting linear spheres or worms also survive emulsification and produce stable n-dodecane-in-water Pickering emulsions. The intrinsic advantages of anisotropic worms over isotropic spheres for the preparation of Pickering emulsions are highlighted. The former particles are more strongly adsorbed at similar efficiencies compared to spheres and also enable smaller oil droplets to be produced for a given copolymer concentration. The scalable nature of PISA formulations augurs well for potential applications of anisotropic block copolymer nanoparticles as Pickering emulsifiers.

Cyclical strain modulates metalloprotease and matrix gene expression in human tenocytes via activation of TGFβ

Tendinopathies are a range of diseases characterised by degeneration and chronic tendon pain and represent a significant cause of morbidity. Relatively little is known about the underlying mechanisms; however onset is often associated with physical activity. A number of molecular changes have been documented in tendinopathy such as a decrease in overall collagen content, increased extracellular matrix turnover and protease activity. Metalloproteinases are involved in the homeostasis of the extracellular matrix and expression is regulated by mechanical strain. The aims of this study were to determine the effects of strain upon matrix turnover by measuring metalloproteinase and matrix gene expression and to elucidate the mechanism of action. Primary Human Achilles tenocytes were seeded in type I rat tail collagen gels in a Flexcell™ tissue train system and subjected to 5% cyclic uniaxial strain at 1 Hz for 48 h. TGFβ1 and TGFβRI inhibitor were added to selected cultures. RNA was measured using qRT-PCR and TGFβ protein levels were determined using a cell based luciferase assay. We observed that mechanical strain regulated the mRNA levels of multiple protease and matrix genes anabolically, and this regulation mirrored that seen with TGFβ stimulation alone. We have also demonstrated that the inhibition of the TGFβ signalling pathway abrogated the strain induced changes in mRNA and that TGFβ activation, rather than gene expression, was increased with mechanical strain. We concluded that TGFβ activation plays an important role in mechanotransduction. Targeting this pathway may have its place in the treatment of tendinopathy.

•

Mechanical strain regulates multiple protease and matrix genes at the mRNA level.

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Changes in mRNA level are analogous to those induced by TGFβ stimulation.

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The inhibition of the TGFβ signalling pathway abrogated the strain-induced changes.

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A SMAD activatory soluble factor is increased in activity in response to mechanical load.

Increased expression of IL-6 family members in tendon pathology

OBJECTIVES

Histological examination of pathological tendon generally does not reveal signs of inflammation. However, the inflammatory cytokine IL-6 has been shown to be expressed in ruptured rotator cuff tendon. The aim of this study was to investigate the expression of IL-6 family members in painful posterior tibialis tendon (PTT) and in painful and ruptured Achilles tendon (AT) compared with normal tendon.

METHODS

AT samples were obtained from cadavers (normal) or from patients undergoing surgical procedures to treat chronic painful tendinopathy or ruptured tendon. PTT samples were obtained from patients undergoing surgery for other reasons (normal) and from patients with PTT dysfunction (painful). Total RNA was extracted and mRNA expression was analysed by quantitative real-time PCR.

RESULTS

Collagen type I α-chain I (COL1A1) expression was increased in both painful PTT and AT compared with normal. Ciliary neurotrophic factor levels were increased in painful PTT only. In the painful AT, cyclooxygenase-2 (COX2) and IL-6 expression increased compared with normal. In the ruptured AT, levels of VEGF A, COX2, oncostatin-M, leukaemia inhibitory factor and IL-6 expression were higher compared with both normal and painful AT. IL-6R expression decreased in both painful and ruptured AT compared with normal.

CONCLUSION

Painful AT and PTT show different expression patterns, indicating a substantial difference between those two tendinopathies. Inflammatory markers are up-regulated in painful and particularly in ruptured AT, pointing towards a role of inflammation not only in rupture healing, but also in Achilles tendinopathy.

A ten-year review of the validity and clinical utility of depression screening

OBJECTIVE

Use of depression screening instruments in primary care is controversial. The authors reviewed research studies published since the development of national practice guidelines to determine whether new evidence might favor screening. The review focused on evidence-related validity and clinical utility of depression screening instruments.

METHODS

Silver Platter MEDLINE was searched for English-language studies of depression screening instruments published between 1986 and 1995. Studies were classified by type--reviews of studies, outcome studies, validation studies.

RESULTS AND CONCLUSIONS

Fifty-nine studies met criteria for review. Validation studies were the most frequent type (39 studies) and were subclassified according to population, type of comparison, and analytical method. These studies documented the validity of screening instruments compared with formal criteria and demonstrated consistently better performance for systematic approaches compared with clinical impressions. Thirteen studies were reviews; those reviewing evidence for effectiveness disagreed in their conclusions. Only seven outcome studies related to depression screening instruments were found, and none showed measurable benefit in a screened population. Several studies showed that very brief instruments performed about as well as longer, well-validated questionnaires for screening in general populations.

The magnitude of metabolic acidosis is dependent on differences in bicarbonate assays

Metabolic acidosis has been recently recognized as an important comorbid event in the high mortality rates seen in patients with end-stage renal disease. The recognition of hypobicarbonatemia is dependent on a reliable assay for total carbon dioxide (TCO2). It is common practice for dialysis facilities to send blood samples for testing to remote laboratories, which may assay bicarbonate differently than the local hospital. We noted that serum bicarbonate concentrations from blood samples sent to our reference laboratory were significantly lower (4 mEq/L) compared with blood samples sent to our local laboratory. Blood samples were assayed for TCO2 using an enzymatic technique (in the reference laboratory) and direct measurement using an electrode (in the local laboratory). The blood test results for TCO2 sent to the reference laboratory (18.7 +/- 0.8 mEq/L) were significantly lower than samples assayed in our local laboratory (22.2 +/- 0.7 mEq/L). In conclusion, recognition of the differences in assays used in the laboratory for routine bicarbonate measurements is important in defining the magnitude of metabolic acidosis and in helping to dictate appropriate therapy.

Early English steroid history

Following the revelation of the presence of vitamin D in fish liver oils and of estrogenic hormones in pregnancy urine in the 1920s, active interest in the steroids began in England. Most of this interest originated from the studies of Ian Heilbron at Liverpool and of Otto Rosenheim at the National Institute for Medical Research in London.

A pragmatist's approach to pathology costing: the Welsh Datatree project

The Datatree costing project in Wales has provided the Welsh pathology laboratories with a standard costing package that allows pathologists to understand how their own laboratory's test costs are compiled. The software provides answers to the question "what if? ..." and shows instantly the effect of salary or consumable cost alterations. Resource management at a laboratory level is enhanced by a greater knowledge of costs, particularly in relation to volumes of work. Perhaps this is one of the stepping-stones across the river to the "open market." In the United Kingdom NHS any information of this kind must be regarded as invaluable.

Attitudes of paediatricians to HIV and hepatitis B virus infection

There is a recent upsurge of interest among health care professionals regarding the risk of accidental occupational exposure to HIV virus. We evaluated knowledge of virus carriage prevalence, needlestick injuries, venepuncture practices, and glove use among paediatricians in Wales and South West Regional Health Authorities. We also attempted to evaluate hepatitis B immunisation uptake in this group. Paediatricians have traditionally been considered a low risk group in the context of accidental occupational exposure to these viruses. We targeted a four point questionnaire at 221 paediatricians. Results suggested that despite recent increasing concern about these viruses, that is reflected in the amount of medical literature recently published, and the issuing of Department of Health guidelines on venepuncture, knowledge of prevalence of HIV and hepatitis B carriage rates, and hence assessment of risk magnitude, was surprisingly poor. Safe venepuncture practices were not widely used. In the 12 months before receiving the questionnaire 55% had suffered a needlestick injury with only 10% reporting the fact. Hepatitis B immunisation uptake was highest in the junior grades (but this does not necessarily mean those at greatest risk). There were many inconsistencies between the clinicians' perceptions of risk and their practices. As the virus attains a firm hold in the heterosexual population paediatricians by virtue of the nature of venepuncture in children will almost certainly see their risk of acquiring HIV/hepatis B viruses secondary to accidental occupational exposure increase over the next decade. Without an improvement in current knowledge of carriage prevalence in high risk areas and alteration in venepuncture practices/hepatitis B immunisation uptake some will unfortunately, though avoidably, contract these bloodborne viral infections.

Occupational medicine residency training programs. The role occupational health nurses play

An experienced occupational health nurse with suitable academic qualifications is able to assist in providing a well-rounded education and teaching physicians to be effective members of occupational health teams. Nurses are involved in teaching occupational health to physicians in the academic and practicum phases of occupational medicine residency training programs. However, the involvement of nurses in training physicians is inconsistent among the accredited residencies. Most of the nurses involved in teaching occupational health to physicians are at least master's degree prepared. Nurses are involved in the didactic, clinical, and administrative components of the training programs. Though nurses are involved in residency training programs to an extent, the lack of consistent involvement limits the diversity of points of view and fosters an imbalance in the training of occupational medicine residents.

Twice daily versus four times daily treatment with beclomethasone dipropionate in the control of mild childhood asthma

The effects of controlling childhood asthma of the same daily dose (400 micrograms) of beclomethasone dipropionate, given in two or four equal divided doses from a metered aerosol, were compared in a double blind crossover study. Thirty one children aged 6-14 years completed the study. They had previously been shown to need beclomethasone by showing either symptoms or reduced peak flow when the treatment was withdrawn. They recorded their daytime and night time symptoms on a visual analogue scale and their morning and evening peak expiratory flow (PEF), and recorded their symptomatic use of bronchodilator aerosols. Spirometry was performed at the end of each treatment period. Control of asthma was good on both regimens. There were small differences in both objective and subjective measurements in favour of the four times daily regimen, but none reached statistical significance, apart from patients' assessment of daytime wheeze (p less than 0.05). In particular, the differences in the results of lung function tests were very small. Compliance was better for morning and evening doses. These results suggest that beclomethasone given as 200 micrograms twice daily is effective in controlling mild childhood asthma. It may be preferable to 100 micrograms four times daily because of better compliance and because it is unnecessary to take medication to school.

Prostaglandins inhibit renal ammoniagenesis in the rat

We describe the inhibitory effect of prostaglandins (PGs) on in vivo rat renal ammonia synthesis. The influence of systemic pH upon urinary PG excretion and ammoniagenesis was also investigated. Finally, PG production by incubated rat renal cortical slices was suppressed to investigate the PG-ammonia interplay in the absence of changes in renal blood flow, glomerular filtration rate, ambient electrolyte concentrations or extrarenal hormonal factors. In vivo ammonia synthesis doubled and PG excretion fell by 44% in normal rats, after intravenous administration of 1 mg/kg of meclofenamate. Higher doses of meclofenamate further augmented ammonia production and further reduced PG excretion. PG depletion was also associated with an increase in fractional excretion of ammonia (FENH3) that was independent of changes in urine flow rate or pH. Acute metabolic acidosis (AMA) increased total ammonia synthesis but also stimulated PG production. Administration of meclofenamate to rats with mild AMA markedly reduced urinary PG excretion, further augmented ammonia synthesis, and significantly increased the FENH3. Inhibition of stimulated PG synthesis during severe AMA did not increase ammoniagenesis or FENH3. Acute metabolic alkalosis did not alter production of PGs or ammonia, but reduced the FENH3 by 42%. Meclofenamate nearly normalized the FENH3 but stimulated synthesis to a lesser degree than was seen in nonalkalotic rats that received meclofenamate. Inhibition of PG synthesis in incubated rat renal cortical slices also stimulated ammoniagenesis. Conversely, stimulation of PG synthesis decreased ammonia production and acidification of the incubation medium increased prostaglandin F2 alpha production. Thus, in vitro findings support the in vivo results. We conclude that PGs inhibit ammonia synthesis in normal rats and in those undergoing mild AMA. Severe acidosis overrides this inhibitory effect of PGs, whereas metabolic alkalosis suppresses the stimulatory effect of PG synthesis inhibition.

Diagnostic strategies in disorders of fluid, electrolyte and acid-base homeostasis

Our understanding of the physiology and biochemistry of acid-base and fluid-electrolyte regulations has greatly expanded in recent years. Key physiologic principles have emerged that now permit rational diagnosis and therapy of clinical disorders of serum electrolyte concentration. This paper describes diagnostic strategies based upon these principles. The etiology of the myriad factors in hyponatremia is best derived by first measuring serum tonicity and then assessing extracellular fluid volume. The hyper-, iso- and hypotonic hyponatremia are defined, and the hypotonic group is subclassified into hypo-, iso- and hyper volemic forms. The hypernatremias are best categorized by their state of volume expansion. Classification into the hypo-, hyper- and isovolemic hypernatremias simplifies their diagnosis. Metabolic acidoses are classified in terms of the anion gap. Clinical and chemical aspects of increased and normal anion gap acidoses are described. Metabolic alkaloses require a source of new bicarbonate and its retention by the kidney. The means by which new alkali is synthesized and urinary loss prevented serve to effectively classify the alkaloses. Hypokalemic syndromes are defined in terms of associated changes in body potassium. The potassium-depleted states are further subclassified by whether normotension or hypertension is associated. Hyperkalemia is produced by redistribution of cellular and extracellular potassium or by increased body potassium. Defects in the renin-angiotensin-aldosterone-distal renal tubule effector arm usually underlie hyperkalemic states, which are than classified in terms of this regulatory hormonal cascade. Classifications for disordered serum concentrations of calcium, magnesium, phosphorus and uric acid are presented. Hormonal, metabolic and renal regulatory factors form the basis for an organized approach to these disorders.

A four-year follow-up of schoolgirls with untreated covert bacteriuria: bacteriological aspects

In 75 schoolgirls aged 5-11 with untreated covert coliform bacteriuria who were followed up to 4 years, infection cleared in 16 (21%), cleared and recurred in 37 (50%) and persisted in 22 (29%). Clearance of bacteriuria was significantly (P less than .05) more frequent in girls with normal radiological findings than in those with abnormal findings. In 31 (59%) of the 53 girls in whom bacteriuria cleared spontaneously, the urine became sterile within the first year after the discovery of the bacteriuria. Spontaneous clearance of bacteriuria was preceded by an increase of the sensitivity of the urinary pathogens to the cidal effect of human serum. Seven (10%) of the 75 untreated bacteriuric girls had shown progression of kidney damage (progression of scarring in 4 and failure of kidney growth in 3). In all of these 7 girls vesico-ureteric reflux (VUR) was present and bacteriuria was persistent, but in 6 of them from one to three changes in the serotype of Esch. coli or bacterial species were noted during follow-up. These observations suggest that changes in bacterial flora may be a risk factor in the progression of kidney damage in girls with urinary tract infection and VUR.

Urinary tract in schoolgirls with covert bacteriuria

During screening of 16,800 primary schoolgirls, aged 4-12 years, in Cardiff and Oxford, significant bacteriuria was found in 294 (1-7%). Intravenous urography and micturating cystography were performed in 246 of these girls. The urinary tract was abnormal in 47%. Pyelonephritis with or without vesicoureteric reflux was present in 26% and reflux without renal abnormality in a further 16%. The prevalence of pyelonephritis and reflux was independent of age. With few exeptions kidneys without pyelonephritic scars appeared to be normal in size, even when ureteric reflux was present.