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After nearly being hunted to extinction during the fur trade of the late 20th Century, sea otter (Enhydra lutris) populations have recovered to varying degrees of their historical range. While overall population numbers and range have increased, there are regions in which expansion has occurred at a slower rate and/or animal numbers have decreased, which may be a result of chronic stress from a variety of sources. Some have employed glucocorticoid analysis in their attempts to validate these explanations. Our goal was to conduct a controlled study using sea otters managed under human care to validate the use of serum glucocorticoid analysis to monitor stress physiology in the sea otter. We used a standard ACTH challenge test to compare cortisol and corticosterone responses, thereby identifying the primary glucocorticoid in the sea otter. Fourteen sea otters of both sexes (five males, nine females), including juveniles, sub-adults and adults, participated in the study. The results of the testing supported cortisol as the primary glucocorticoid in the sea otter. Sex and age did not affect how the individual responded to the ACTH or saline injection. Interestingly, the saline injection not only confirmed the effects of the ACTH on glucocorticoid release from the adrenal glands but also provided information on how long it takes the sea otter’s glucocorticoid levels to return to baseline after capture and sedation. The insight gained from this study will aid in future efforts to better understand the role of stress in free-ranging sea otter populations. Recognition of the primary glucocorticoid will facilitate evaluation of more stable biological material, such as fur or whiskers, which tend to be less affected by the diurnal cycling of glucocorticoids.

Gastric fluid pH was measured in five adult horses following nasogastric administration of famotidine, 0.5, 1.0, and 2.0 mg/kg bodyweight (bwt); ranitidine, 4.4 and 6.6 mg/kg bwt and an antacid containing magnesium hydroxide (40 mg/ml) and aluminium hydroxide (45 mg/ml), 120 and 180 ml. Fluid was aspirated through a 16 French nasogastric feeding tube at 15 min intervals, and pH was measured using a pH meter. Basal gastric fluid pH was measured at 20 min intervals for 6 h in each horse and, with the exception of two measurements of 4.66 and 4.17, ranged from 1.42 to 2.41, with a mean pH of 1.88 +/- 0.18. The response to both ranitidine and famotidine was variable between horses and between dosages. The mean gastric fluid pH values following administration of a single dose of famotidine or ranitidine were famotidine, 0.5 mg/kg bwt, 3.63 +/- 1.72; famotidine, 1.0 mg/kg bwt, 3.41 +/- 1.40; famotidine, 2.0 mg/kg bwt, 4.18 +/- 2.06; ranitidine, 4.4 mg/kg bwt, 4.07 +/- 1.25; ranitidine 6.6 mg/kg bwt, 5.34 +/- 1.12. Differences in mean gastric fluid pH between famotidine dose levels and between ranitidine dose levels were not significant (P > 0.10). Gastric fluid pH increased to greater than 6 in three horses receiving 0.5 mg/kg bwt, five horses receiving 1.0 mg/kg bwt and three horses receiving 2.0 mg/kg bwt famotidine. Gastric fluid pH increased to greater than 6 in each of the five horses receiving 6.6 mg/kg bwt ranitidine and in four of five horses receiving 4.4 mg/kg bwt ranitidine. During the 6 h post administration, ranitidine tended to increase gastric fluid pH greater than 6 longer (166 +/- 106 mins) than famotidine (98 +/- 110 mins) and this difference was nearly significant (P = 0.054). The response to antacid was variable and consistently short-lived. The mean gastric fluid pH values for 6 h after administration of 120 ml or 180 ml were 2.42 +/- 0.71 and 2.44 +/- 0.47, respectively. Gastric fluid pH increased to greater than 6 in only two horses, for 15 and 30 mins, respectively. The increase in gastric fluid pH was significantly greater for ranitidine (P < 0.001) and famotidine (P < 0.02) than for antacid. The duration of the effect was significantly longer for ranitidine doses (P < 0.001) and nearly so for famotidine doses (P < 0.055) than for antacid.

A paste formulation of the H+,K(+)-ATPase inhibitor omeprazole was evaluated in Thoroughbred foals and yearlings for its safety and acceptability. Twenty foals age 11-16 weeks and 20 yearling horses age 15-17 months were included and gastroscopic examinations performed 1-3 days before and at the end of each trial. Lesions were scored on a scale of 0 to 3 and animals allocated based on endoscopic lesion score and sex, with 4 animals in each of 5 replicates. Dosages of 4 mg omeprazole/kg bwt or sham treatment were administered once daily for 28 days, from a syringe graduated in 50 lb (22.68 kg) increments, the amount of paste administered being rounded up to the nearest corresponding weight in pounds. Acceptability of the paste or sham treatment was assessed and recorded by the individual administering the treatment on the basis of the tolerance or resistance to insertion of the syringe into the mouth, administration of the paste and if the paste was swallowed or actively expelled by the animal. Safety was determined on the basis of daily observation recordings and physical examination findings during and at the conclusion of the trial. Treatment was judged to have been accepted for all 420 doses of omeprazole paste and all 140 sham doses given to foals during the trial and for 418/420 doses of paste and all 140 sham doses given to yearlings. Two doses of paste were entirely rejected by yearlings. On the initial endoscopic examination, lesions were observed in the gastric squamous epithelial mucosa in 4 foals and 3 yearlings, and single small, superficial erosions were seen in the gastric glandular mucosa of 2 foals. On the second examination there were small, superficial erosions in the squamous mucosa in 3 foals and 2 yearlings, multi-focal superficial erosions in 1 foal and 1 yearling, and 1 foal had large areas of erosion extending from the margo plicatus toward the dorsal fundus. No lesions in the glandular mucosa were seen in foals or yearlings. There were no significant differences (P < 0.05) in lesion scores between the beginning and the end of the trials in the omeprazole-treated or sham-treated groups of foals or yearlings. A paste formulation of omeprazole, administered at a dose of 4 mg/kg bwt once daily for 28 days, was determined to be highly acceptable to the foals and yearlings we studied, and no adverse effects attributable to the medication were noted.

Summary This study examined whether a product containing a pectin-lecithin complex (Pronutrin)1 could prevent gastric lesions induced in the equine gastric squamous epithelial mucosa using a protocol of intermittent feed deprivation that resulted in prolonged increased gastric acidity (Murray and Eichorn 1996). Eight ponies were used and served as theirown controls in 2 trials in which there were 72 h cumulative deprivation (alternating 24 h with no feed, then 24 h free choice hay), with a 4-week interval between trials. Ponies were assigned randomly to receive either 250 g Pronutrin plus 200 g pelleted feed, or 450 g pelleted feed only. Ponies were conditioned to each treatment for 7 days and received Pronutrin and pellets oronly pellets once daily during the feed deprivation protocol. Gastroscopy was performed at the beginning and conclusion of the feed deprivation protocol. The endoscopist (M.J.M.) was blinded as to treatments, and lesion severity was scored on a scale of 0–5. Gastroscopy revealed normal-appearing gastric mucosa at the beginning of feed deprivation, with the exception of 2 ponies which had focal squamous mucosal erosion and 1 pony with focal glandularmucosal erosion. After 72 h cumulative feed deprivation, each pony, except 1 pony in one of the trials, developed erosions or ulcers in the gastric squamous mucosa. There was no difference (P = 0.6) in the presence or severity of gastric lesions between treatments. Lesions did not develop in the gastric glandular mucosa as a result of the intermittent feed deprivation with either treatment. In this study, the pectin-lecithin complex in Pronutrin failed to prevent lesions in the gastric squamous mucosa induced by intermittent feed deprivation.

Summary The objective of the study reported here was to characterise the microscopic appearance of peptic-injured equine gastric squamous epithelium in relation to the duration of peptic injury. Erosions and ulcers were induced in equine gastric squamous epithelium using a feed deprivation protocol that results in prolonged increased gastric acidity. Specimens of normal gastric mucosa and mucosa with lesions created after 48 and 96 h of feed deprivation were compared for characteristics associated with angiogenesis and mucosal proliferation. Fifteen mature horses, 9 geldings and 6 mares, age 3–20 years, were divided into 3 groups. Group 1 (n = 5) had normal-appearing gastric squamous mucosal epithelium and had been killed due to problems unrelated to the gastrointestinal tract. Groups 2 (n = 5) and 3 (n = 5) had lesions induced in the gastric squamous epithelium by alternating 24 h periods of feed deprivation and ad libitum access to hay, for totals of 48 and 96 h feed deprivation, respectively. Following lethal injection of barbiturate, stomachs were removed and fixed by filling with 4–6 l 10% buffered formalin. Sections were made from lesions in the gastric squamous epithelium adjacent to the margo plicatus along the right side of the stomach/greatercurvature and the lesser curvature. Measurements of total epithelial thickness, keratinised epithelium, nonkeratinised epithelium, epithelial projections, capillary extension into the epithelium and lamina propria thickness were made. The cross-sectional areas of arterial and venous vascularstructures in the lamina propria at the lesions and theirmargins were measured using image analysis software. All horses, except one, in Group 2 developed erosions or ulcers in the gastric squamous epithelium after feed deprivation. There were several changes in the epithelium adjacent to erosions and ulcers, compared to normal epithelium, from horses in Groups 2 and 3: total epithelial thickness was significantly (P

Leukaemia and lymphoma may present with symptoms and signs mimicking common respiratory conditions of childhood such as asthma or croup. The UK National Institute for Clinical Excellence guidelines for referral for suspected cancer state that "the primary healthcare professional should be ready to review the initial diagnosis in patients in whom common symptoms do not resolve as expected" and "must be alert to the possibility of cancer when confronted by unusual symptom patterns" (National Institute for Health and Clinical Excellence, 2005).A child with an undiagnosed mediastinal mass presenting with signs and symptoms suggestive of asthma or croup may be given oral systemic steroids. We report four such illustrative cases presenting to a single institution within the last 3 years.We highlight key points from the history and examination findings which should lead to review of the original diagnosis, the benefit of early chest X-ray in such cases and the dangers of steroid pretreatment.

Context. Observations of large-scale solar emergence events indicate that the magnetic field is already twisted prior to its emergence. However, the nature of twist of the pre-emergence field is largely unknown. Aims. By testing two different twist profiles for subsurface magnetic flux tubes, we aim to identify any differences in the emergence process of the field and its atmospheric signatures that occur as a result of the twist. Given that differences do occur, future comparisons of these emergence results with observations should reveal specific properties of the twist of the subsurface magnetic field. Methods. Using a 3D numerical MHD code, we consider a simple stratified model, comprising of one solar interior layer and three overlying atmospheric layers. We set a horizontal, twisted flux tube in the lowest layer and prescribe the central protion along the tube’s length to be buoyant so that it will rise towards the surface. We test two different non-constant twist profiles for the tube and perform a parameter study for each profile, looking for differences and similarities during the rise, emergence and expansion stages of the tube’s evolution. Results. We find that, irrespective of the tube’s twist profile, if the tube initially has a low tension force then it will experience greater expansion and consequential weakening of its field strength during the rise through the solar interior. Thus, upon reaching the solar surface it will fail to undergo a magnetic buoyancy instability and will not emerge into the atmosphere. For those tubes that do emerge into the atmosphere, there is little distinction between the atmospheric field and few indicators as to the initial twist profile of the tube. In general, tubes with stronger tension forces have a faster growth rate of the magnetic buoyancy instability, while tubes with weaker tension forces expand to a greater degree in the horizontal direction post-emergence. Synthesised magnetograms at the solar surface do vary between the two tested twist profiles but only in cases with initially low tension forces. Conclusions. Upon emergence, it appears that most of the specific details of the tube’s initial twist are lost. The field must initially be sufficiently twisted such that it is able to undergo a magnetic buoyancy instability but such a level of twist subsequently results in the emerging flux having generic atmospheric characteristics. Only in cases with an initially low tension force is it possible to make some distiction post-emergence by considering magnetograms at the solar surface.

Context. There has been suggestions that the initial subsurface magnetic field in flux emergence models is too organised. Thus, it may be that the results they yield are very specific and cannot be applied to the generic flux emergence process occurring on the Sun. Aims. We will demonstrate that the interaction of two flux tubes can increase the complexity of the solar interior’s magnetic field. However, the subsequent emergence of this complex field results in the atmospheric flux having a simple and generic structural form. Methods. Using a numerical 3D MHD code, we consider the evolution of two flux tubes within a vertically stratified domain, representing the upper layers of the solar interior through to the corona. The flux tubes are initially situated in the solar interior, one tube lying directly above the other. By choosing the lower tube to be buoyant, whilst the upper tube is in mechanical equilibrium with its surroundings, we encourage the interaction of the two tubes within the solar interior. Thus, we will create a more complex magnetic field lying just below the photospheric surface than would be generated with a single flux tube model. By studying the subsequent emergence and structure of the resulting atmospheric field we will be able to identify if there are any significant changes due to the increased complexity of the field below the surface. Results. The reconnection process modifies the topology of the subsurface magnetic field as indicated by the results of previous simulations. Since reconnection is occurring in a high plasma-β region, where the sound speed is greater than the Alfven speed, we observe no significant jets and also find no significant heating. When this reconnected field comes to the surface it is complex but the emergence occurs in much the same manner as for a single flux tube and, therefore, produces very little change in the atmospheric field. This strongly indicates that the results of previous emergence simulations are valid for both simple and complex subsurface fields.

Reports of increasing numbers of obese Australian children and adolescents have raised the alarm to be proactive in reducing this so called epidemic. It has evoked a call for greater emphasis on teaching physical education in schools, as a measure for attaining fitness not only with obese students but for all students. This paper emphasises how preservice teachers need to be a key target for implementing physical education (PE) reform in schools, as many primary teachers will be generalists and may not be confident enough to implement PE effectively. Through a review of existing literature, teaching practices essential for the effective promotion and implementation of PE were identified under six broad categories: personal-professional skills development, addressing system requirements, pedagogical practices, managing student behaviour, providing feedback to students, and reflecting on practice. Subsequently, the development of these practices in preservice teachers is considered in the context of a university-school collaboration where preservice teachers taught physical education to primary school students for one day per week over a four week period. These authentic teaching experiences provided the preservice teachers with vital opportunities to put theory into practice and interact with “real-world” students. Self-evaluative data from 38 of these preservice teachers, in the form of a five-part Likert scale survey and extended response survey, demonstrated that they were able to develop the majority of the essential teaching practices identified by literature. In particular, the preservice teachers developed self efficacy, enthusiasm, and motivation for teaching PE, facets which are often found to be lacking in generalist primary teachers and yet are essential if children’s perceptions and habits regarding physical activity are to be changed.

A poor validation strategy will compromise the quality of satellite-derived sea surface temperature (SST) products because confidence limits cannot be quantified. This paper addresses the question of how to provide the best operational strategy to validate satellite-derived skin sea surface temperature (SST skin) measurements. High quality in situ observations obtained using different state-of-the-art infrared radiometer systems are used to characterize the relationship between the SST skin, the subsurface SST at depth (SSTdepth), and the surface wind speed. Data are presented for different oceans and seasons. These data indicate that above a wind speed of approximatel y6ms 21 the relationship between the SSTskin and SSTdepth, is well characterized for both day- and nighttime conditions by a cool bias of 20.17 6 0.07 K rms. At lower wind speeds, stratification of the upperocean layers during the day may complicate the relationship, while at night a cooler skin is normally observed. Based on these observations, a long-term global satellite SST skin validation strategy is proposed. Emphasis is placed on the use of autonomous, ship-of-opportunity radiometer systems for areas characterized by prevailing low‐wind speed conditions. For areas characterized by higher wind speed regimes, well-calibrated, qualitycontrolled, ship and buoy SSTdepth observations, corrected for a cool skin bias, should also be used. It is foreseen that SSTdepth data will provide the majority of in situ validation data required for operational satellite SST validation. We test the strategy using SSTskin observations from the Along Track Scanning Radiometer, which are shown to be accurate to approximately 0.2 K in the tropical Pacific Ocean, and using measurements from the Advanced Very High Resolution Radiometer. We note that this strategy provides for robust retrospective calibration and validation of satellite SST data and a means to compare and compile in a meaningful and consistent fashion similar datasets. A better understanding of the spatial and temporal variability of thermal stratification of the upper-ocean layers during low‐wind speed conditions is fundamental to improvements in SST validation and development of multisensor satellite SST products.

Gastric ulcers are highly prevalent in foals, and severe ulcers can develop as early as 2 days of age. Gastric acidity can be very high in foals, particularly between nursing activities. Hydrochloric acid can begin damaging the gastric epithelium within minutes of exposure. Risk factors for ulcers include illness and other conditions that result in decreased nursing and feeding. Foals with severe illness, such as septicemia, may have reduced gastric mucosal blood flow, further predisposing the gastric lining to injury. Clinical signs may not be apparent in foals until ulcers are very severe, and when clinical signs are noted, treatment should be very aggressive. Drugs that block gastric acid secretion are recommended, and the proton pump inhibitors, such as omeprazole, are particularly recommended.

Objective—To determine the effects of 8 days of light to heavy exercise on gastric ulcer development in horses and determine the efficacy of omeprazole paste in preventing gastric ulceration. Design—Randomized, controlled, multicenter clinical trial. Animals—102 horses with normal-appearing gastric mucosa on endoscopic examination that were in light to heavy training. Procedures—Horses at 4 trial locations were allocated into replicates and sham dosed orally (empty syringe) or treated with a paste formulation of omeprazole (1 mg/kg [0.45 mg/ lb], PO) once daily for 8 days. Training regimens varied among locations and included early training for western performance events; walking, trotting, and cantering in a mechanical exerciser; and race training (2 locations). Prevalences of gastric ulceration at the completion of the 8-day treatment period were compared between groups. Results—At the end of the 8-day treatment period, the proportion of omeprazole-treated horses free from gastric ulceration (88%) was significantly higher than the proportion of sham-dosed horses free from gastric ulceration (27%). Conclusions and Clinical Relevance—Results showed that horses in light to heavy training for as short as 8 days were at risk of developing gastric ulcers and that administration of omeprazole paste decreased the incidence of gastric ulcers.

There are limited methods of assessing pulmonary function in horses at rest. We developed clinical techniques to measure gas exchange efficiency in horses and evaluated 3 groups of horses that were 1) asymptomatic based on auscultation with rebreathing, transtracheal aspirate cytology, and thoracic radiographs (n = 6), 2) asymptomatic at rest but symptomatic with rebreathing (n = 11) and 3) symptomatic at rest (n = 9). Blood samples were obtained from the transverse facial artery and jugular vein. Maximal end-tidal CO2 tension (PETCO2) was measured by an infrared capnograph through a facemask. Alveolar O2 tension, dead space fraction (V(D)/V(T)), and physiological shunt fraction (Q(S)/Q(T)) were calculated using standard formulae. Arterial O2 tension in Group 1 horses (mean +/-s.d.103+/-3 mmHg) was significantly higher than in Group 2 or Group 3 horses. Q(S)/Q(T) in Group 1 horses (0.37+/-0.98%) was significantly lower than in Group 2 and Group 3 horses. Mean +/-s.d.V(D)/V(T) in Group 1 horses (-18.2+/-3.1) was significantly lower than Group 3 horses but not Group 2 horses.

The prevalence of thyroid peroxidase autoantibodies (TPO.Ab) was assessed in patients with either breast carcinoma or benign breast disease, and its association with disease outcome in breast carcinoma was studied. TPO.Ab were detected by direct RIA in serum from 121/356 (34.0%) of patients with breast carcinoma, compared with 36/194 (18.5%) of controls (P or = 0.3 U/mL were associated with a significantly better disease-free [relative risk (RR) = 1.84, P 18.8 mL. Multivariate survival analysis showed that both TPO.Ab and thyroid volume were independently associated with prognosis in breast carcinoma and that RRs for disease-free survival were of a similar order of magnitude to well-established prognostic indices such as axillary nodal status or tumor size. These findings supply evidence that manifestations of thyroid autoimmunity are associated with a beneficial effect on disease outcome in breast carcinoma and provide the strongest evidence to date of a biological link between breast carcinoma and thyroid disease.

Of 17 foals born on a Thoroughbred breeding farm between March and April 1995, infection with equine herpesvirus type 1 (EHV-1) was associated with neonatal morbidity in 5 foals, 3 of which died or were euthanized. Morbidity and mortality were associated with pulmonary inflammation, and EHV-1 was identified in the lungs of the 3 foals that died. All neonatal EHV-1 infections occurred in foals of mares housed in the same pasture and barn. No other clinical manifestations of EHV-1 infection (e.g., abortion, neurologic disease, or respiratory disease) occurred during this outbreak. Three foals were treated with acyclovir (1 died, 2 survived), which may have influenced the clinical outcome in the surviving foals.

Summary Whole blood and serum were collected from foals to determine the prevalence of Equine herpesvirus type 2 (EHV2) infection in foals, age at which infection can first be identified and serological responses to infection. Equine herpesvirus type 2 was isolated from peripheral blood mononuclear cells (PBMC) from 68 of 69 foals, 1–8-months-old, sampled once. Virus isolation was performed twice at intervals of 2–7 months on PBMCs from 33 foals and EHV2 was isolated on both occasions in all but one foal (negative, then positive). Regression analysis of log2-transformed reciprocal serum EHV2 virus neutralising (VN) titres revealed that in foals age 1–7 months, EHV2 VN antibody titre was positively correlated with age (r = 0.94). Paired serum samples were obtained from 58 foals, with the first samples collected age 1–6 months and the second samples collected 2–4 months later. There were significant (P

Summary Gastroscopic examinations were performed on 67 Thoroughbred horses in training at a race track and repeat examinations performed in 35 horses, 2 to 3 months later. Horses were age 2–9 years and included 16 two-year-olds, 32 three-year-olds and 19 horses ≥ 4-years-old. Forty-two of the 67 horses had raced within the 2 months before the initial examination and the remaining 25 horses were in training. Sixty-two of the 67 horses (93%) had one or more lesions present in the gastric mucosa and lesions were present in all of the 42 horses that had raced. Thirty-two of the 35 horses, examined twice (91%), had gastric lesions on the first examination and all had lesions on the second examination. Four sites of the gastric squamous epithelium were graded for lesion severity on a scale of 0 to 10 and the mean maximum squamous mucosal lesion score was significantly (P

Summary Transtracheal wash and bronchoalveolar lavage are diagnostic techniques that have been adopted from human medicine for monitoring inflammatory changes in the airway of the horse. Transendoscopic biopsy has also proven to be a valuable tool for obtaining samples of the airway mucosa in human patients. A transendoscopic technique was developed in this study for obtaining a respiratory mucosal biopsy from standing, sedated horses. Six normal adult horses were sampled at eight-week intervals for a total of three sample periods. Horses were monitored for adverse effects of the technique and none were noted. Sample sites were completely healed after eight weeks with no gross or histologic abnormalities. Biopsy samples were 3 to 4 millimeters in diameter, and 17 of 18 samples provided interpretable histological sections. Methods for handling, staining and evaluating tissue were also developed. The results of this study demonstrated that airway mucosal biopsy is a safe, repeatable technique that can be performed in the sedated, standing horse.

Despite extensive study, evidence to support a direct relationship between diseases of the thyroid and breast has not been established. In this study thyroid volume was assessed by ultrasound in 200 patients with breast cancer and 354 with benign breast disease. Results were compared to appropriate female control groups. Both mean thyroid volume (21.1 +/- 1.4 mL) and the percentage of individual patients with enlarged (> 18.0 mL) thyroid glands (41.5%) were significantly greater in the breast cancer group than equivalent values (13.2 +/- 0.5 mL and 10.5%, respectively) in age-matched controls (P < 0.01 in both cases). The mean thyroid volume of 14.5 +/- 0.34 mL in patients with benign breast disease was also significantly greater than that of 12.5 +/- 0.38 mL in younger controls (P < 0.01). The results support a direct association between breast cancer and increased thyroid volume as mean thyroid volumes and the percentage of individual patients with enlarged thyroid glands were similar in those studied both before (20.8 +/- 1.3 mL and 43.0%) and after (21.4 +/- 1.6 mL and 40.0%) therapies for breast cancer. Although there is no evidence that thyroid enlargement represents a risk factor for breast cancer, the results emphasize the importance of raising the consciousness of the coincidence of both disorders.

Background : Our earlier uncontrolled observations during primary famine and subsequent refeeding did not suggest that severe undernutrition inevitably increases vulnerability to infection. Some infections appeared suppressed by famine but reactivated by refeeding. Aims : To examine prospectively the occurrence of infections in a large cohort of primary famine victims before and during refeeding. Methods : From 1973 to 1993, 4382 famine victims aged 14 or more with an estimated weight loss greater than 25% were weighed and examined for infection before and after one, two, three and four weeks ofrefeeding. In 137, serum C-reactive protein was measured in an effort to detect latent asymptomatic infections before and after two weeks ofrefeeding. Refeeding diets included wheat, sorghum, millet, ghee and milk powder. Results : Mean weight loss ± SD was 28.7 ± 2.3%. Before refeeding overt infections were found in 4.9%, an incidence rising to 29.1% at two weeks of refeeding and declining after four. Those developing infections gained more weight at two weeks, 4.6 3 ± 0.81 kg, than those never infected, 3.94 ± 0.76 (p = < 0.001 t test). C-reactive protein levels confirmed the presence of latent infections before refeeding. Conclusions : Severe undernutrition can suppress certain infections, mostly those due to intracellular pathogens and especially P. falciparum. Refeeding reactivates suppressed infection and can increase vulnerability to certain new infections especially ofviral origin. Those gaining weight the most rapidly may be at greatest risk. Refeeding with foods alien to local culture could play a role in reactivating latent infections. Our findings may be limited to severe undernutrition and not apply to lesser forms or secondary undernutrition in hospital patients. These studies were done during charitable provision of medical care to famine victims.

Westward-propagating waves with periods of 20–30 days and wavelengths of ∼ 1,100km are a prominent feature of sea-surface temperatures (SSTs) in the equatorial Pacific and Atlantic Oceans. They have been attributed to instabilities due to current shear. We compare SST observations from the spaceborne Along Track Scanning Radiometer (ATSR) and TOGA-TAO moored buoys with SSTs from a model of the tropical Pacific forced with observed daily windstress data. The phases of the strongest “Tropical Instability Waves” (TIWs) in the model are in closer correspondence with those observed than we would expect if these waves simply developed from infinitesimal disturbances (in which case their phases would be arbitrary). If we filter out the intraseasonal component of the windstress, all phase-correspondence is lost. We conclude that the phases of these waves are not arbitrary, but partially determined by the intraseasonal winds. The subsurface evolution of the model suggests a possible control mechanism is through interaction with remotely-forced subsurface Kelvin and Rossby waves. This is supported by an experiment which shows how zonal wind bursts in the west Pacific can modify the TIW field, but other mechanisms, such as local feedbacks, are also possible.

Ulceration of the gastric squamous epithelial mucosa was induced in 10 horses using a feeding protocol previously shown to expose the gastric mucosa to repeated periods of high acidity. The feeding protocol consisted of alternating feed deprivation with free access to hay. Over a period of seven days, each horse was provided hay for 84 hr and deprived of hay for 84 hr. Hay was never withheld for longer than 24 hr at a time. Gastroscopy was performed on each horse at the beginning of the protocol after 12 hr of feed deprivation, and after a total of 36 hr, 60 hr, and 84 hr of feed deprivation. All horses had normal esophageal and gastric mucosa at the beginning of the protocol. Alternating periods of feeding and feed deprivation resulted in progressive ulceration of the gastric squamous epithelial mucosa in all but one of the horses. Lesions progressed from erosions to ulceration within 36-72 hr of feed deprivation, and by 84 hr of feed deprivation ulcers had developed thickened, raised margins. Esophageal mucosa appeared normal in all horses throughout the study. The protocol of alternating feeding with feed deprivation in horses consistently produced gastric squamous epithelial ulceration and provided a useful model for characterizing temporal transitions in peptic-injured alimentary squamous epithelia.

α-Fetoprotein (AFP) measurements have clinical implications in fetal medicine and, in infants and older children, in detection, differential diagnosis and monitoring of malignant disease. Maternal serum AFP levels constitute part of a multiple-marker test used in early second-trimester screening to predict risk of fetal chromosomal abnormalities. Those individuals with increased risk are offered further definitive diagnostic investigation. Second-trimester screening is now increasingly being superseded by first-trimester screening with other serum markers and ultrasound. As AFP is only produced physiologically during fetal development, elevated serum levels after the first two post-natal years usually indicate the presence of a malignant disease process. Before this time, levels may be purely physiological and therefore serial values should be plotted on a logarithmic chart to ensure that they are falling appropriately, with a typical half-life of ∼5-6 days. If not, further investigation should be undertaken. Serum AFP is raised in a significant proportion of germ cell tumours (GCTs), hepatoblastoma and hepatocellular carcinoma (HCC). In suspected cases of GCT, serum human choriogonadotropin (HCG) estimation should also be performed. For possible intracranial GCTs, both serum and cerebrospinal fluid levels of AFP and HCG should be measured, ideally before neurosurgical biopsy. In malignant conditions, serum AFP may be used for diagnosis, treatment monitoring, surveillance for disease recurrence and prognostication. Immunohistochemistry for AFP using antibody staining is routinely used to assist pathological diagnosis on tissue sections where the differential includes GCT, hepatoblastoma and/or HCC. Elevations of serum AFP also occur in non-malignant conditions such as chronic liver disease.

Specimens of grossly normal gastric stratified squamous epithelial mucosa adjacent to the margo plicatus on the right side and along the greater curvature were obtained from 7 foetuses, 10 term foals and 12 foals 2-35 days old. Gastric squamous epithelium from the foetuses changed markedly during gestation. At 150-270 days, the epithelium was 8-10 cells thick, with a single layer of basal cells. Epithelial cells were polyhedral and had abundant clear or slightly stained cytoplasm. In the 300-day foetus the basal layer was thicker, epithelial cells were polyhedral, and there was a flattened 1 cell-thick layer superficially. In the 335-day foetus, the epithelial cells were flat and there was a superficial layer of keratinised cells, 1-2 cells thick. In term foals, the gastric epithelium consisted of 10-12 cell layers, with 4-5 thin layers of surface keratin. Epithelial projections (papillae) were either absent or not pronounced. The gastric epithelium became thicker with increasing age, including increased epithelial cell layers, thickening of the keratinised layers, and more pronounced papillae. Desquamation was observed in the keratinised layers of gastric squamous epithelium from foals > or = 2 days of age.

A glass combined pH-reference electrode was placed in the stomachs of 5 adult horses and pH was recorded every 6 mins for 24 h while (1) feed and all bedding materials were withheld for 24 h (unfed), (2) horses had free access to Timothy grass hay for 24 h (fed), and (3) horses had free access to Timothy grass hay and were treated with ranitidine, 6.6 mg/kg body weight, orally, every 8 h for 48 h (fed + ranitidine). There was a significant (P = 0.007) difference in median 24-h gastric pH amongst the 3 protocols, the value being 3.1 in fed horses and 1.55 in unfed horses (P = 0.05) and 4.6 in fed + ranitidine horses (P = 0.05 compared with fed horses). The percentage of pH readings2.0 was significantly greater (P = 0.05) in unfed (76%) than in fed (30%) horses, and in fed horses than in fed + ranitidine (9%) horses. The percentage of readings2.0, 3.0, 4.0, 5.0 and 6.0 were each significantly (P = 0.05) greater in fed + ranitidine horses than in fed horses, and in fed than in unfed horses. There was no difference (P = 0.13) between median gastric pH values from different times of day in unfed horses (00:00 to 06:00 h, 1.5; 06:00 to 12:00 h, 1.6; 12:00 to 18:00 h, 1.7; and 18:00 to 24:00 h, 1.5). We conclude that gastric acidity is greatest when horses do not have access to feed material and that ranitidine effectively suppresses gastric acidity in horses under conditions of free access to hay.

Sixteen neonatal foals stressed by disease underwent endoscopic examination of their stomachs and blood was assayed for triiodothyronine (T3), reverse T3 (rT3), thyroxine (T4) and cortisol, to determine the effects of severe physiological stress and the occurrence of gastric ulcers. compared with eight age-matched controls, six foals had abnormal cortisol, seven had abnormal T3 and 12 had abnormal T4. Eleven of 13 foals had rT3 outside the 95 per cent confidence interval for clinically normal foals of comparable ages. Gastric lesions were seen more frequently in stressed foals, and gastric glandular mucosal lesions were noted in 40 per cent of the stressed foals. Previous studies report low (3 per cent) occurrence of gastric mucosal lesions. The frequency of squamous mucosal lesions was not different from that reported previously, indicating that stress has little effect on the development of lesions at this site.

Katie, an 11-year-old, previously healthy Caucasian girl presents to her general practitioner (GP) with a 2-month history of being generally unwell with lethargy, loss of appetite, anorexia and aching legs. Past medical history reveals febrile convulsions as a young child but nothing else of note. Katie was born at term by normal delivery, is fully immunised and is on no current medication. Examination is unremarkable save for some small, shotty 1 cm diameter cervical and inguinal lymph nodes. Weight is 45 kg (75–90th centile) and height is 155 cm (90–95th centile). The GP is concerned about a possible diagnosis of malignancy, particularly given the history. She therefore decides that further investigation is warranted and requests a full blood count (FBC). FBC reveals haemoglobin 10.3 g/dl, white cell count (WCC) 45.5×109/l and platelets 128×109/l. Blood film reveals the presence of circulating lymphoblasts, suggestive of acute lymphoblastic leukaemia (ALL). Katie is referred to the tertiary paediatric oncology centre, where the diagnosis is confirmed by bone marrow examination and induction chemotherapy commenced according to the current ALL protocol. A central venous catheter is inserted for administering chemotherapy, other medication and blood sampling. She receives co-trimoxazole (septrin) routinely for Pneumocystis carinii pneumonia (PCP) prophylaxis. At the end of the 28-day induction phase, repeat bone marrow examination confirms that Katie is in morphological remission. Katie tolerates the subsequent blocks of chemotherapy well (consolidation followed by two alternating courses of interim maintenance and delayed intensification). Shared care is provided by her local district general hospital and she starts maintenance chemotherapy at week 46 of treatment, as per the protocol. Her central venous catheter is removed at this stage as it is only required infrequently for chemotherapy now and is considered to be an ongoing infection risk. At week 90, Katie develops intermittent …