Bcl-6 expression by CD4+ T cells determines concomitant immunity and host resistance across distinct parasitic infections

Cluster of differentiation (CD4+) T cells consist of multiple subtypes, defined by expression of lineage-specific transcription factors, that contribute to the control of infectious diseases by providing help to immune and nonimmune target cells. In the current study, we examined the role of B cell lymphoma (Bcl)-6, a transcriptional repressor and master regulator of T follicular helper cell differentiation, in T cell-mediated host defense against intestinal and systemic parasitic infections. We demonstrate that while Bcl-6 expression by CD4+ T cells is critical for antibody-mediated protective immunity against secondary infection with the nematode Heligmosoides polygyrus bakeri, it paradoxically compromises worm expulsion during primary infection by limiting the generation of interleukin-10 (IL-10)-producing Gata3+ T helper 2 cells. Enhanced worm expulsion in the absence of Bcl-6 expressing T cells was associated with amplified intestinal goblet cell differentiation and increased generation of alternatively activated macrophages, effects that were reversed by neutralization of IL-10 signals. An increase in IL-10 production by Bcl-6-deficient CD4+ T cells was also evident in the context of systemic Leishmania donovani infection, but in contrast to Heligmosoides polygyrus bakeri infection, compromised T helper 1-mediated liver macrophage activation and increased susceptibility to this distinct parasitic challenge. Collectively, our studies suggest that host defense pathways that protect against parasite superinfection and lethal systemic protozoal infections can be engaged at the cost of compromised primary resistance to well-tolerated helminths.

A protocol for generating germ-free Heligmosomoides polygyrus bakeri larvae for gnotobiotic helminth infection studies

The microbes indigenous to helminth species are a major obstacle to deciphering host-parasite interactions. Repurposing a system of reversible bacterial colonization, we have generated germ-free Heligomosomoides polygyrus bakeri (Hpb) larvae that maintain the sterility of axenic mice upon infection. This protocol provides a valuable tool for controlled studies of helminth-microbiota-immune interactions.

•

Protocol for rearing viable germ-free Hpb larvae

•

Larvae maintain infectivity and immunogenicity in specific pathogen-free mice

•

Larvae do not contaminate germ-free mice upon infection

•

Experimental tool to parse helminth-immune-microbiota interactions

Richard Dadd: the patient, the artist, and the "face of madness"

Richard Dadd (1817-1886) was a well-known Victorian artist who murdered his father, compelled by the delusion that a demonic force possessed his father's body. He was one of the first to bypass execution by reason of insanity and spent the remainder of his life in the Bethlem and Broadmoor asylums. Dadd is rare both as a patient and an artist because he left behind nearly a 40-year record of artwork and journals, which constitute a unique medical and psychiatric resource at a time when the ideas on the relationship of facial expression and madness were changing. Sir Charles Bell's (1774-1842) widely accepted views that the "face of madness" is bestial and anatomically distinctive were being challenged by such physicians as Sir Alexander Morison (1779-1866), who was also Dadd's own "alienist" (i.e., psychiatrist). The purpose of this article is to explore the nature and extent of the influence of Bell and Morison on Dadd, which has not been brought out in the existing studies. By a comparative analysis, it will be shown that Dadd may have conveyed a different view in his works that foreshadows subsequent developments that are closer to a modern understanding.

Is BMR repeatable in deer mice? Organ mass correlates and the effects of cold acclimation and natal altitude

Basal metabolic rate (BMR) is probably the most studied aspect of energy metabolism in vertebrate endotherms. Numerous papers have explored its mass allometry, phylogenetic and ecological relationships, and ontogeny. Implicit in many of these studies (and explicit in some) is the view that BMR responds to selection, which requires repeatability and heritability. However, BMR is highly plastic in response to numerous behavioral and environmental factors and there are surprisingly few data on its repeatability. Moreover, the mechanistic underpinnings of variation in BMR are unclear, despite considerable research. We studied BMR repeatability in deer mice (Peromyscus maniculatus) across intervals of 30-60 days, and also examined the influence of birth altitude (3,800 m versus 340 m) and temperature acclimation (to approximately 5 or approximately 20 degrees C) on BMR, and the relationship between BMR and organ size. Neither acclimation temperature nor natal altitude alone influenced BMR, but the combination of birth at high altitude and cold acclimation significantly increased BMR. Few visceral organ masses were correlated to BMR and most were inconsistent across natal altitudes and acclimation temperatures, indicating that no single organ 'controls' variation in BMR. In several treatment groups, the mass of the 'running motor' (combined musculoskeletal mass) was negatively correlated to BMR and the summed mass of visceral organs was positively correlated to BMR. We found no repeatability of BMR in any treatment group. That finding-in sharp contrast to high repeatability of BMR in several other small endotherms-suggests little potential for direct selection to drive BMR evolution in deer mice.

Local staging of prostate cancer with 0.2 T body coil MRI

This study was undertaken to evaluate the accuracy of low field strength body coil MRI in the staging of clinically localized prostate cancer. Fifty-three patients with prostate cancer were examined on a 0.2 T body coil system before undergoing radical prostatectomy. Of the 20 cases with unconfined stage T3 disease on histology, 12 were correctly staged, whilst three cases were overstaged by MRI. (Accuracy 79.2%, sensitivity 60%, and specificity 90.9%.) The accuracy, sensitivity and specificity for the detection of capsular penetration were 77.3%, 55% and 90.9%, respectively, whilst those for seminal vesical invasion were 94.3%, 83.3% and 95.7%, respectively. It is concluded that a high level of staging accuracy, comparable to that obtained in some published studies using high field strength endorectal coil MRI, can be obtained using 0.2 T body coil MRI.

Randomised controlled trial of allopurinol prophylaxis in very preterm infants

Allopurinol, an inhibitor of xanthine oxidase (an enzyme capable of generating superoxide radicals following hypoxiaischaemia), was investigated in preterm infants to determine its ability to prevent the complications of neonatal intensive care which may be associated with oxidative injury. Four hundred infants of between 24 and 32 weeks' gestation were randomly allocated to receive enteral allopurinol (20 mg/ml) or an equivalent dose of placebo for seven daily doses. At admission, plasma hypoxanthine concentrations were significantly higher in infants who subsequently developed periventricular leucomalacia (PVL), bronchopulmonary dysplasia (BPD), or retinopathy of prematurity (ROP), but there was no difference in the primary endpoint (PVL) between the treated and control groups. The failure of allopurinol prophylaxis in this group of infants is probably related to the complex nature of the pathological processes and to the timing of treatment. If oxidant injury is an important mechanism of cellular injury in these preterm infants, an alternative biochemical modulator would be required, or a combination of agents might be effective.

Antioxidants and neonatal lung disease

Bronchopulmonary dysplasia (BPD) remains a clinical problem in survivors of neonatal intensive care despite recent advances which include surfactant replacement. Oxygen toxicity may well be a component in the pathogenesis of BPD and disturbance of the oxidant-antioxidant balance constitutes a biochemical problem which should be addressed in the management of preterm babies. Preterm babies appear to have inadequate antioxidant potential and yet when delivered may experience considerable oxidant stress. This imbalance may be ameliorated by antenatal steroid therapy which augments pulmonary antioxidants as well as surfactant production. Augmentation of antioxidants by administration of exogenous enzymes such as superoxide dismutase and catalase is possible in animal models but the clinical use of such therapies awaits further research.

Extra-pharyngeal neck pathology complicating pharyngeal pouch surgery

One case each of: (1) low grade thyroid lymphoma; (2) supraclavicular and para-oesophageal metastasis of a uterine adenocarcinoma; and (3) recurrent multinodular goitre have been encountered in very intimate relationship with the neck of a pharyngeal pouch within the tracheo-oesophageal gutter raising the possibility that the two conditions were interrelated. The practical importance of these cases is that a surgeon excising a pouch from the neck ought to be able to resect a thyroid lobe should it prove necessary, and occasionally endoscopic diverticulotomy is the only reasonable option.

Receiver operating characteristic curves for comparison of serial neutrophil band forms and C reactive protein in neonates at risk of infection

The performance of indirect indices of infection in the newborn vary because of differences in techniques, including diagnostic cut off levels. We have compared serial neutrophil band cell counts with C reactive protein measured by rate nephelometry. The 'gold standard' was a positive culture and the performance of the tests was compared by the technique of receiver operating characteristics (ROC) as well as sensitivity and specificity. A total of 172 septic screens were performed in 56 patients. The operational diagnostic cut off values were: C reactive protein greater than 8 mg/l, immature:total neutrophil ratio (I:T ratio) greater than 0.2, and band count greater than 5%. Compared with the sensitivity of C reactive protein (71%), I:T ratio (34%) was significantly different but band count (69%) was not. The specificity of C reactive protein (72%) was better than band count (39%) but no better than I:T ratio (73%). ROC curves were constructed for all possible diagnostic cut off values of the tests and superior performance was demonstrated for C reactive protein compared with band count and I:T ratio. We conclude that C reactive protein is a useful early indicator of infection in neonates and that ROC curves permit comprehensive and graphic comparison between tests and the calculation of optimal diagnostic cut off values.

Plasma hypoxanthine: a marker for hypoxic-ischaemic induced periventricular leucomalacia?

Cerebral ischaemia of the immature brain may result in cavitating periventricular leucomalacia (PVL), an important association of cerebral palsy. Hypoxanthine measured by high performance liquid chromatography was used as a marker of peripartum hypoxia and ischaemia in 116 infants at risk of PVL. PVL was detected by ultrasound. The 81 infants who were unaffected had median (range) gestation of 30 weeks (24-32), weight of 1336 g (724-3790), and a plasma hypoxanthine concentration of 7.8 mumol/l (2.4-48.9). The seven infants who had cavitating PVL had a median gestation of 28 weeks (26-30), weight of 1165 g (682-1860), and a hypoxanthine concentration of 31.9 mumol/l (7.1-149). Cavitating PVL was significantly dependent only on hypoxanthine when controlling for the effects of weight and gestation. This suggests that peripartum hypoxia-ischaemia may be one of the aetiological factors in cavitating PVL. Oxidation of hypoxanthine during reperfusion generates free radicals which may contribute to the tissue destruction of PVL. The association of hypoxia-ischaemia with PVL suggests that PVL may be modified by reducing free radical activity.

Squamous metaplasia in the penile urethra due to oestrogen therapy

Histological examination was performed on the anterior penile urethra from 21 asymptomatic trans-sexual patients taking oestrogens prior to surgery. Squamous metaplasia was present in 15 of these patients and in 1 man taking progesterones. Immunohistochemical staining for oestrogen receptors in the urethra was negative. Severe squamous metaplasia was associated with patchy chronic inflammatory cell infiltration but this was also present in normal controls. The lack of recognised complications of squamous metaplasia at this site suggests that it is an incidental observation in men taking oestrogens.

Patterns of ductal tissue in coarctation of the aorta in the first three months of life

A possible relationship between recurrence of coarctation and the presence of residual ductal tissue in the aorta was studied by defining the presence and pattern of ductal tissue in aortic segments from 23 patients less than 3 months of age who underwent resection of coarctation of the aorta. The surgical policy was to perform extensive excision of the coarctation, including a wide margin of descending aorta beyond the ductus arteriosus. Histologic examination showed that there was a circumferential sling of ductal tissue extending from the ductus arteriosus and surrounding the aorta at the level of the coarctation shelf in 22 specimens. In 15 of these specimens one or two tonguelike prolongations of ductal tissue extended distally from the circumferential sling and occupied constant positions in the aortic wall; one tonguelike prolongation extended distally below the insertion of the ductus and the other from the circumferential sling opposite the ductal insertion. Incomplete excision of ductal tissue was found in 11 specimens. In relation to the goal of avoiding recurrent coarctation after repair in the early months of life, the possible implications of these findings are discussed, and, in particular, a possible mechanism of recurrence after subclavian flap aortoplasty is proposed.

Autoimmune Addison's disease and thyrotoxic thyroiditis presenting as encephalopathy in twins

An 11 year old boy who presented with neuropsychiatric symptoms including delirium and pronounced agitation was found to have simultaneous onset of autoimmune adrenocortical insufficiency and hyperthyroidism. His identical twin also had hyperthyroidism and six months later developed symptoms of adrenocortical insufficiency. In children presenting with neuropsychiatric symptoms, adrenal (or pituitary) and other endocrine disorders should be considered.

Postmortem audit in a paediatric cardiology unit

Postmortem examinations performed on 76 children with a clinical diagnosis of congenital heart disease were reviewed retrospectively and compared with the findings before death. Both operated and unoperated cases were studied over a three year period. Despite intensive investigation during life, there was a high rate of unsuspected abnormalities at necropsy (80%): 29 cases had undiagnosed additional cardiac anomalies or surgical flaws, which contributed to death in 13 cases. Defects in surgery were uncommon but permitted modification in surgical technique to avoid recurrence. Myocardial necrosis and pulmonary foreign body embolism were common findings, the importance of which is uncertain and requires further study for their prevention. Even in the most thoroughly investigated cases postmortem examination has a high yield of clinically important pathology which is undetected during life.

Studies on adenosine triphosphate transphosphorylases. XVIII. Synthesis and preparation of peptides and peptide fragments of rabbit muscle ATP-AMP transphosphorylase (adenylate kinase) and their nucleotide-binding properties

Two peptide fragments, derived from the head and tail of rabbit muscle myokinase, were found to possess remarkable and specific ligand-binding properties (Hamada et al., 1979). By initiating systematic syntheses and measurements of equilibrium substrate-binding properties of these two sets of peptides, or portions thereof, which encompass the binding sites for (a) the magnesium complexes of the nucleotide substrates (MgATP2- and MgADP-) and (b) the uncomplexed nucleotide substrates (ADP3- and AMP2-) of rabbit muscle myokinase, some of the requirements for binding of the substrates to ATP-AMP transphosphorylase are being deduced and chemically outlined. One requirement for tight nucleotide binding appears to be a minimum peptide length of 15-25 residues. In addition, Lys-172 and/or Lys-194 may be involved in the binding of epsilon AMP. The syntheses are described as a set of peptides corresponding to residues 31-45, 20-45, 5-45, and 1-45, and a set of peptides corresponding to residues 178-192, 178-194, and 172-194 of rabbit muscle adenylate kinase. The ligand-binding properties of the first set of synthetic peptides to the fluorescent ligands: epsilon MgATP/epsilon ATP and epsilon MgADP/epsilon ADP are quantitatively presented in terms of their intrinsic dissociation constants (K'd) and values of N (maximal number of moles bound per mole of peptide); and compared with the peptide fragment MT-I (1-44) obtained from rabbit muscle myokinase (Kuby et al., 1984) and with the native enzyme (Hamada et al., 1979). In addition, the values of N and K'd are given for the second set of synthetic peptides to the fluorescent ligands epsilon AMP and epsilon ADP as well as for the peptide fragments MT-XII(172-194) and CB-VI(126-194) (Kuby et al., 1984) and, in turn, compared with the native enzyme. A few miscellaneous dissociation constants which had been derived kinetically are also given for comparison (e.g., the Ki for epsilon AMP and the value of KMg epsilon ATP obtained for the native enzyme) (Hamada and Kuby, 1978), and the K'd measured for Cr3+ ATP [corrected] and the synthetic peptide I1-45 (Fry et al., 1985b).

Flecainide toxicity

Flecainide toxicity occurred in an infant being treated for refractory atrioventricular re-entry tachycardia. Ventricular tachycardia developed when dextrose was substituted for milk feeds. We believe that milk was interfering with the absorption of flecainide, and so a high serum concentration developed when milk feeds were stopped.

Coexistent cardiac tumours and malformations of the heart

Cardiac tumours and anatomical malformations of the heart may produce similar clinical signs and symptoms. The coexistence of these two abnormalities complicates diagnosis and probably adversely affects prognosis. We present a review of four cases of this rare combination. In the first case, Ebstein's malformation was present in a child with tuberous sclerosis and cardiac rhabdomyomata. Right ventricular rhabdomyomata were associated with a hypoplastic tricuspid valve in the second case. In the third case, cardiac myxomas were detected in a child with a double-chambered right ventricle. The fourth case was a child with a fibroma of the right ventricle with pulmonary atresia. We propose that, in some circumstances, a space-occupying lesion may be associated with, or possibly induce, a malformation within the developing heart.

Aspergillus ball thrombus occluding a homograft conduit

Almost total occlusion of an aortic homograft conduit by a ball of Aspergillus terreus was found postmortem in a 6-month-old infant following repair of a type I truncus arteriosus. Signs of pulmonary hypertensive crisis, fever, anaemia, and thrombocytopenia were present. However, blood cultures were persistently negative. A 2-D echocardiogram failed to demonstrate any vegetation. The clinical, pathological, and postmortem findings are described and difficulties in the diagnosis of Aspergillus infection are discussed.

Post mortem radiology in children with congenital heart disease

Contrast radiology has valuable applications in routine necropsy practice. Contrast radiology was used to study the vascular anatomy in four normal fetuses, in five children with cardiovascular malformations, and in two hearts prepared by the perfusion fixation method. A contrast radiograph provides permanent documentation of anatomical associations before they are disrupted by dissection and permits a planned approach to the necropsy. While these injection studies are seldom undertaken by pathologists because they are felt to be too difficult and time-consuming, contrast studies should form part of the post mortem investigation of children with congenital heart disease, even when angiography has been performed in life.

Conducting system in foamy myocardial transformation of infancy

Images

Diminished pulse pressure under mental stress characterizes normotensive adolescents with parental high blood pressure

An exaggerated blood pressure response to mental stress is believed to characterize young adults with genetic risk of essential hypertension, suggesting that stress-induced changes might provide a useful index of pathogenetic processes. We explored this by studying pressor responsivity to competitive tasks in adolescents drawn from a large urban population. Individuals with systolic or diastolic pressures persistently between the 85th and 95th percentiles were evaluated on basal blood pressure, parental history of hypertension, and pressor and heart rate response to a challenging video game. Basal pressure was measured again at 6, 10, and 14 months. A persistently diminished pulse pressure was the cardiovascular characteristic that most reliably typified normotensive subjects with familial hypertension. Response to the video game was the best indicator of risk status. Contrary to expectations derived from research with convenience samples, epidemiologic investigation points to an increased peripheral resistance and lower cardiac output as the cardiovascular pattern more prominently associated with genetic risk in the normotensive adolescent.

The complete amino acid sequence of chicken skeletal-muscle enolase

The complete amino acid sequence of chicken skeletal-muscle enolase, comprising 433 residues, was determined. The sequence was deduced by automated sequencing of hydroxylamine-cleavage, CNBr-cleavage, o-iodosobenzoic acid-cleavage, clostripain-digest and staphylococcal-proteinase-digest fragments. The presence of several acid-labile peptide bonds and the tenacious aggregation of most CNBr-cleavage fragments meant that a commonly used sequencing strategy involving initial CNBr cleavage was unproductive. Cleavage at the single Asn-Gly peptide bond with hydroxylamine proved to be particularly useful. Comparison of the sequence of chicken enolase with the two yeast enolase isoenzyme sequences shows that the enzyme is strongly conserved, with 60% of the residues identical. The histidine and arginine residues implicated as being important for the activity of yeast enolase are conserved in the chicken enzyme. Secondary-structure predictions are analysed in an accompanying paper [Sawyer, Fothergill-Gilmore & Russell (1986) Biochem. J. 236, 127-130].

The predicted secondary structure of enolase

The results of several secondary-structure prediction programs were combined to produce an estimate of the regions of alpha-helix, beta-sheet and reverse turn for both chicken skeletal-muscle and yeast enolase sequences. The predicted secondary-structure content of the chicken enzyme is 27% alpha-helix and less than 10% beta-sheet, whereas in the yeast enolase a similar helix content but virtually no sheet are predicted. These results are in fair agreement with published experimental estimates of the amount of secondary structure in the yeast enzyme. The enzyme appears to be formed from three domains.

Approaches to the demonstration of congenital heart disease

Advances in antenatal screening techniques have increased the interest in obtaining a detailed pathological correlation with the ultrasonographic findings obtained before death. As a consequence, inadequacies in traditional methods used by pathologists to display congenital malformations have been brought to light. We describe a simple technique of inflation and wax impregnation for the permanent proof of congenital heart defects that can be used in routine perinatal necropsies.

Narcissism and the narcissistic personality disorder: a comparison of the theories of Kernberg and Kohut

Narcissism has been a perennial topic for psychoanalytic papers since Freud's 'On narcissism: An introduction' (1914). The understanding of this field has recently been greatly furthered by the analytical writings of Kernberg and Kohut despite, or perhaps because of, their glaring disagreements. Despite such theoretical advances, clinical theory has far outpaced clinical practice. This paper provides a clarification of the characteristics, diagnosis and development of the narcissistic personality disorder and draws out the differing treatment implications, at various levels of psychological intensity, of the two theories discussed.

Coronary sinus type atrial septal defect in a child with pulmonary atresia and Ebstein's anomaly

At birth an infant was found to have an unusual series of abnormalities with a coronary sinus type atrial septal defect complicating pulmonary atresia with an intact ventricular septum and Ebstein's anomaly. The functionally important anomalies were diagnosed by echocardiography and cardiac catheterisation. The coronary sinus defect and Ebstein's anomaly were detected only at necropsy. Although only a single case, the features of this heart favour Bull's revised classification of pulmonary atresia.

Electron Spin Resonance Spectroscopy: Application to Proof of Structure of Organic Ketones

Many ketones containing an alpha-methylene group can be converted to alpha-diketone radical anions in dimethyl sulfoxide solution. The resulting radical anions can usually be unambiguously identified by electron spin resonance spectroscopy, and the structure of the starting ketone may be deduced, often without reference to model compounds. The technique is also applicable to alpha-diketones, alpha-bromoketones, and alpha-hydroxyketones.