Subacute Angle-Closure Glaucoma as a Cause of Headache in the Presence of a White Eye

Three patients, initially diagnosed with headache syndromes, were subsequently found to have subacute angle-closure glaucoma. In each case, the eye appeared grossly normal and there were no visual symptoms. A comprehensive ophthalmologic examination, including gonioscopy, confirmed the diagnosis. Laser iridotomy was curative with complete resolution of head and face pain. Subacute angle-closure glaucoma is an exception to the maxim that a white eye is not the cause of a painful eye.

Expression patterns of Notch1, Serrate1, Serrate2 and Delta1 in tissues of the developing chick limb

Signalling via the receptor Notch, delivered by the ligands Delta and Serrate, plays a key role in many cell fate decisions in both Drosophila and vertebrate development (for review seeArtavanis-Tsakonas, S., Matsuno, K. and Fortini, M.E., 1995. Notch signalling. Science 268, 225-232; Lewis, J., 1996. Neurogenic genes and vertebrate neurogenesis. Curr. Opin. Neurobiol. 6, 3-10; Blair, S.S., 1997. Limb development: marginal fringe benefits. Curr Biol. 7, 686-690; Irvine, K.D. and Vogt, T.F., 1997. Dorsal-ventral signaling in limb development. Curr. Opin. Cell Biol. 9, 867-876). Recently vertebrate homologues of Notch (Notch1; Myat, A., Henrique, D., Ish-Horowicz, D. and Lewis, J., 1996. A chick homologue of Serrate and its relationship with Notch and Delta homologues during central neurogeneis. Dev. Biol. 174, 233-247) and Serrate (Serrate1 and 2; Myat, A., Henrique, D., Ish-Horowicz, D. and Lewis, J., 1996. A chick homologue of Serrate and its relationship with Notch and Delta homologues during central neurogeneis. Dev. Biol. 174, 233-247; Hayashi, H., Mochii, M., Kodama, R., Hamada, Y., Mizuno, N., Eguchi, G. and Tachi, C., 1996. Isolation of a novel chick homolog of Serrate and its coexpression with Notch-1 in chick development. Int. J. Dev. Biol. 40, 1089-96; Laufer, E., Dahn, R., Orozco, O.E., Yeo, C.Y., Pisenti, J., Henrique, D., Abbott, U., Fallon, J.F. and Tabin, C., 1996. Expression of Radical fringe in limb-bud ectoderm regulates apical ectodermal ridge formation. Nature 386, 366-373; Rodriguez-Esteban, C., Schwabe, J.W., De La Pena, J., Foys, B., Eshelman, B. and Izpisua-Belmonte, J.C., 1997. Radical fringe positions the apical ectodermal ridge at the dorsoventral boundary of the vertebrate limb. Nature 386, 360-366) were shown to be expressed in early chick limb mesenchyme and apical ridge. However, later expression patterns of these genes and of Delta 1 (Henrique, D. , Adam, J., Myat, A., Chitnis, A., Lewis, J. and Ish-Horowicz, D., 1995. Expression of a Delta homologue in prospective neurons in the chick. Nature 375, 787-790) in vertebrate limbs have not been documented. We have used whole mount in-situ hybridization to document expression patterns of Notch1, Serrate1, Serrate2 and Delta1 within the mesenchyme of the developing chick limb up to stage 31 of development. We show these genes are expressed, in different combinations, in the vasculature, the musculature and the tissues of the handplate.

Peter B. Samuels Award. Restenosis after percutaneous transluminal angioplasty

BACKGROUND

Determine the feasibility of studying the natural history of the atherosclerotic plaque following percutaneous transluminal angioplasty (PTA), using duplex scanning.

METHODS

Twenty-three patients with 40 stenoses (>70% and <5 cm in length) in the iliac and femoro-popliteal segments were studied by duplex scanning before PTA, on day 1, weekly for 8 weeks, and at 3 months, 6 months, and 1 year. The following measurements were made: thickness of the plaque, minimal lumen diameter (MLD), and peak systolic velocity ratio (PSVR). A PSVR >2.0 was used to indicate >50% lumen diameter reduction.

RESULTS

Thirty stenoses were available for measurement and analysis. Mean reduction in plaque thickness after angioplasty was greater in echolucent plaques (2.33 +/- 0.9 mm) than echogenic plaques (0.83 +/- 0.6 mm; P < 0.0001). Successful angioplasty (PSVR <2.0) and increase in MLD in echolucent plaques was the result of plaque compression; in echogenic plaques, of wall dilatation. The incidence of restenosis (PSVR >2.0) at 6 months was 12 of 30 (40%) remaining unchanged at 1 year; of the lesions that restenosed, 33% recurred before week 8 and the remainder between weeks 8 and 24, suggesting different mechanisms. During follow-up, all plaques showed "growth"; <2 mm in 17 (57%; group A) and >2 mm in the remaining 13 (43%; group B). The incidence of restenosis (PSVR >2.0) was 4 of 17 (23%) in group A and 8 of 13 (61%) in group B (P <0.05).

CONCLUSION

Duplex scanning provides valuable information on both luminal diameter and plaque thickness; it may be used to study the natural history of plaques following angioplasty and also the effects of therapeutic agents aimed at reducing restenosis.

Effect of cane use on tibial strain and strain rates

The effect of cane ambulation on hip biomechanics has been well studied, but its effect on tibial strains and strain rates is not known. To test the hypothesis that cane use may lower tibial strain and strain rates during walking, percutaneous axial extensometers were mounted on the right medial cortex of the midtibial diaphysis in seven male volunteers. In vivo peak-to-peak axial tibial strains and strain rates were measured for ipsilateral and contralateral cane usage and compared with a no cane control. Cane-assisted ambulation was not found to significantly lower strain magnitudes; however, tibial strain rates were significantly lowered by both ipsilateral and contralateral cane usage. We conclude that either ipsilateral or contralateral cane usage may be beneficial when lowering tibial strain rate is desired, such as in the treatment of tibia stress fracture or osteoarthrosis of the knee.

Responding to health changes: a case study of dental health conditions and systems in Japan and Australia

This paper presents an analysis of the main policy and organisational issues confronting dental health systems in Japan and Australia. Using the changes in the epidemiology of dental disease (the oral disease which still affects much of public dental health planning) as evidence of fundamental differences in the dental health systems of the two countries, the analysis seeks to illuminate, first, the structures and processes in both nations to review and implement changes to educational practices and workforce planning and, second, the constraints on each nation's capability to respond quickly and appropriately to the changing dental health needs. It is argued that Japan's ability to rapidly change its oral health outcomes, its dental educational system and its traditional workforce structure and service-mix, is more constrained than appears to be the case in the Australian dental system. The major barriers to Japan's ability to change appear to lie in both its traditional cultural decision-making processes and in a series of specific health and educational structures which place high reliance on a private educational system for health providers, a national insurance system which rewards treatment under a fee-for-service reimbursement scheme and the lack of a formal, transparent, infra-structure for planning health priorities. Barriers to Australia achieving culturally appropriate oral health outcomes for the next century appear more related to whether national unity in goal setting and implementation strategies can be achieved. The constraints in Australia are related to its federal system and to the low priority given to financing public dental services.

Analysis of complement receptor type 1 (CR1) expression on erythrocytes and of CR1 allelic markers in Caucasian and African American populations

CR1 expression on erythrocytes (E) is regulated by an element that is tightly linked in Caucasians to the site of an RFLP of the CR1 gene. Genomic HindIII fragments of 7.4 and 6.9 kb identify alleles that are expressed in high (H allele) or low (L allele) amounts, respectively. When age-fractionated E of donors heterozygous for both the H and L alleles and for CR1 allotypes of differing molecular weights were analyzed in Western blots, the product of the L allele appeared to have an increased rate of loss during cell aging. A coding sequence polymorphism of CR1 predicted to cause a Pro-->Arg substitution in its proximal extramembranous region was tightly linked in Caucasians to the site of the HindIII RFLP. However, neither this polymorphism nor the HindIII RFLP correlated with CR1 expression among African Americans. Relative instability of CR1 encoded by the L allele thus may derive from another coding sequence polymorphism, or may require both the Pro-->Arg substitution and epistatic effects of another polymorphic gene.

A common human beta globin splicing mutation modeled in mice

The betaIVS-2-654 C-->T mutation accounts for approximately 20% of beta thalassemia mutations in southern China; it causes aberrant RNA splicing and leads to beta0 thalassemia. To provide an animal model for testing therapies for correcting splicing defects, we have used the "plug and socket" method of gene targeting in murine embryonic stem cells to replace the two (cis) murine adult beta globin genes with a single copy of the human betaIVS-2-654 gene. No homozygous mice survive postnatally. Heterozygous mice carrying this mutant gene produce reduced amounts of the mouse beta globin chains and no human beta globin, and have a moderate form of beta thalassemia. The heterozygotes show the same aberrant splicing as their human counterparts and provide an animal model for testing therapies to correct splicing defects at either the RNA or DNA level.

Echocardiographic quantitation of mitral regurgitation: a new Doppler technique

Our objective is to develop a new transthoracic Doppler echocardiographic technique to determine mitral regurgitant fraction. The standard color Doppler method for assessment of mitral regurgitation is semiquantitative and dependent on instrument gain. By using the mitral and aortic valve continuous wave Doppler velocities, one can determine regurgitant fraction. This technique takes into account the flow dependence of the mitral valve area. Two constants, A and B, which represent the flow dependence of the mitral valve area and the ratio of the mitral valve area to aortic valve area at zero flow, respectively, were determined by regression in 36 patients without valvular disease (r = .89). Thirty patients with isolated mitral regurgitation were then studied. The mitral regurgitant fraction was calculated from the following: Regurgitant fraction = 1 - TVIav/Bf[Vmv/(1 - AVmv)]dt, where TVIav is the time velocity integral across the aortic valve, Vmv is the continuous wave velocity across the mitral valve, and A and B are constants. The regurgitant fraction was then compared with color Doppler assessment of mitral regurgitation assessed by independent observers. In patients with mitral regurgitation, there was a strong correlation between standard visual assessment and our new Doppler method (Kendall's tau b rank correlation = 0.65; p < .001). The new Doppler method was able to correctly categorize 90% of patients with mild mitral regurgitation and 88% of patients with severe mitral regurgitation; however, there was poorer agreement with the color Doppler assessment of moderate mitral regurgitation. Mitral regurgitant fraction can be calculated with our new Doppler method. This method is quantitative, objective, nongain dependent, and separates mild from severe mitral regurgitation well.

Rapid genotyping of mice with hemoglobinopathies and globin transgenes

The hematology of the laboratory mouse has been well characterized. Normal genetic differences at the alpha- and beta-globin gene loci serve as useful markers for a wide variety of types of experimental studies. There are a number of naturally occurring or induced mutations that disrupt globin expression and produce thalassemic phenotypes. In addition, much has been learned of the workings of the globin locus control region from studies of transgenic mice, including those with mutations induced by targeted site-specific modifications. After a new mutation or transgene has been created, it must be maintained in living mice, and the genotypes of the offspring must be ascertained. While it is possible to determine genotypes by DNA analyses, such assays are time consuming and relatively expensive. An osmotic challenge test--originally developed for the genotyping of large-deletion alpha-thalassemia mutations in mice--has proven useful in detecting both severe and milder alpha- and beta-thalassemias, as well as some transgenic genotypes in mice carrying human globin genes. Reliable genotyping can, in some cases, be completed within a few minutes with minimal expense. Quantification of red cell fragility for a variety of thalassemic and transgenic mice is described here, along with a simplified test suitable for rapid, routine genotyping. The osmotic challenge test is perfectly reliable for distinguishing genotypes that cause significantly decreased release of hemoglobin from the red cells, but it is also useful for some of the conditions in which overall erythrocyte osmotic fragility is essentially normal.

Multiple delta genes and lateral inhibition in zebrafish primary neurogenesis

In Drosophila, cells are thought to be singled out for a neural fate through a competitive mechanism based on lateral inhibition mediated by Delta-Notch signalling. In tetrapod vertebrates, nascent neurons express the Delta1 gene and thereby deliver lateral inhibition to their neighbours, but it is not clear how these cells are singled out within the neurectoderm in the first place. We have found four Delta homologues in the zebrafish--twice as many as reported in any tetrapod vertebrate. Three of these--deltaA, deltaB and deltaD--are involved in primary neurogenesis, while two--deltaC and deltaD--appear to be involved in somite development. In the neural plate, deltaA and deltaD, unlike Delta1 in tetrapods, are expressed in large patches of contiguous cells, within which scattered individuals expressing deltaB become singled out as primary neurons. By gene misexpression experiments, we show: (1) that the singling-out of primary neurons, including the unique Mauthner cell on each side of the hindbrain, depends on Delta-Notch-mediated lateral inhibition, (2) that deltaA, deltaB and deltaD all have products that can deliver lateral inhibition and (3) that all three of these genes are themselves subject to negative regulation by lateral inhibition. These properties imply that competitive lateral inhibition, mediated by coordinated activities of deltaA, deltaB and deltaD, is sufficient to explain how primary neurons emerge from proneural clusters of neuroepithelial cells in the zebrafish.

Clean-catch versus urine collection pads: a prospective trial

Two methods for collecting urine samples from very young children were compared in a paediatric ward of a busy district general hospital. Samples collected using urine collection pads were compared to the standard clean-catch method using sterile foil bowls. No significant differences were observed in the outcome of tests from samples collected by the two methods over the course of a short nurse-led trial, and the hospital has adopted the urine collection pad for routine paediatric UTI sampling.

Positive regulatory gamma delta T cells in contact sensitivity: augmented responses by in vivo treatment with anti-gamma delta monoclonal antibody, or anti-V gamma 5 or V delta 4

Contact sensitivity (CS) responses, induced by skin painting with reactive haptens like picryl chloride or oxazolone, are classical examples of in vivo immunity mediated by alpha beta T cells. Our previous studies showed that gamma delta T cells were required to assist the alpha beta CS-effector T cells in the successful adoptive cell transfer of CS responses. These spleen and lymph node-derived gamma delta+ CS-assisting regulatory cells were CD3+, CD4-CD8+, non-antigen-specific, and non-MHC-restricted, and preferentially expressed V gamma 5 and V delta 4 variable regions. In the current study we show that systemic treatment of mice in vivo with anti-gamma delta mAb, produced a similar positive influence on CS responses in two different systems: i.e. active sensitization, or adoptive cell transfer. In addition to augmented CS responses produced by treatment with pan anti-gamma delta TCR mAb, anti-gamma delta-V region mAb were examined, and augmentation of CS also was produced by anti-V gamma 5 and anti-V delta 4 mAb, the V regions determined previously to be preferentially expressed on gamma delta CS-assisting cells. We speculate that the positive influence of anti-gamma delta mAb was not caused by quantitative changes in gamma delta T cells, because FACS studies demonstrated a lack of in vivo depletion of peripheral blood and lymphoid gamma delta T cells, and also no depletion of epidermal dendritic gamma delta T cells (DETC), in mice treated with anti-gamma delta TCR mAb. Instead, our data favor the hypothesis that CS-assisting gamma delta T cells can be activated in vivo by anti-gamma delta TCR mAb interacting with their gamma delta TCR, at least with the short term protocols we employed, resulting in augmentation of CS responses perhaps by releasing positively-acting factors, such as certain cytokines.

The issue of never-married motherhood in Britain, 1920-70

This article examines shifts in attitudes and changes in provision with regard to never-married mothers within three broad chronological periods. The first section considers attitudes towards these mothers in the period 1918-45, when the issue was conceptualized as one of public health and moral welfare. Second, the article examines the period between 1945 and 1970, when the dominant professional view of never-married mothers focused on identifying individual pathology, but when significant continuities in treatment can nevertheless be found. Third, the article looks briefly at the substantial change in policy and provision for what were then called 'one-parent families' during the 1970s. In conclusion it argues that while there were substantial changes in terms of the way in which unmarried motherhood was defined, from the point of view of the unmarried mothers themselves the continuities have been more striking. Unmarried mothers have been persistently singled out and labelled a social problem and, in all but a brief period during the late 1960s and 1970s, also as a moral problem.

Umbilical cord blood interleukin-6 levels and neonatal morbidity

OBJECTIVE

To study umbilical cord interleukin-6 levels and the occurrence of neonatal sepsis, congenital pneumonia, necrotizing enterocolitis, and grade II-IV intraventricular hemorrhage.

METHODS

Umbilical cord blood was collected from 133 preterm newborns. The study population was divided according to the presence or absence of neonatal complications. Interleukin-6 levels and clinical characteristics were compared by univariate and multivariate analyses.

RESULTS

Sixteen neonates had adverse outcomes, and 117 were unaffected. The median interleukin-6 level was significantly higher in affected than in unaffected infants (145 pg/mL versus 0 pg/mL, P = .002). Elevated interleukin-6 levels were associated independently with neonatal morbidity in multiple logistic regression modeling that included gestational age, birth weight, and antenatal steroid exposure.

CONCLUSION

Umbilical cord blood interleukin-6 levels are elevated in neonates who subsequently develop sepsis, congenital pneumonia, necrotizing enterocolitis, or grade II-IV intraventricular hemorrhage.

Maintenance of neuroepithelial progenitor cells by Delta-Notch signalling in the embryonic chick retina

BACKGROUND

Neurons of the vertebrate central nervous system (CNS) are generated sequentially over a prolonged period from dividing neuroepithelial progenitor cells. Some cells in the progenitor cell population continue to proliferate while others stop dividing and differentiate as neurons. The mechanism that maintains the balance between these two behaviours is not known, although previous work has implicated Delta-Notch signalling in the process.

RESULTS

In normal development, the proliferative layer of the neuroepithelium includes both nascent neurons that transiently express Delta-1 (Dl1), and progenitor cells that do not. Using retrovirus-mediated gene misexpression in the embryonic chick retina, we show that where progenitor cells are exposed to Dl1 signalling, they are prevented from embarking on neuronal differentiation. A converse effect is seen in cells expressing a dominant-negative form of Dl1, Dl1(dn), which we show renders expressing cells deaf to inhibitory signals from their neighbours. In a multicellular patch of neuroepithelium expressing Dl1(dn), essentially all progenitors stop dividing and differentiate prematurely as neurons, which can be of diverse types. Thus, Delta-Notch signalling controls a cell's choice between remaining as a progenitor and differentiating as a neuron.

CONCLUSIONS

Nascent retinal neurons, by expressing Dl1, deliver lateral inhibition to neighbouring progenitors; this signal is essential to prevent progenitors from entering the neuronal differentiation pathway. Lateral inhibition serves the key function of maintaining a balanced mixture of dividing progenitors and differentiating progeny. We propose that the same mechanism operates throughout the vertebrate CNS, enabling large numbers of neurons to be produced sequentially and adopt different characters in response to a variety of signals. A similar mechanism of lateral inhibition, mediated by Delta and Notch proteins, may regulate stem-cell function in other tissues.

Alterations of the endogenous surfactant system in septic adult rats

Sepsis is the most common factor leading to the acute respiratory distress syndrome (ARDS) and is associated with the highest mortality rate. It has been suggested that the pulmonary surfactant system is altered and contributes to the lung dysfunction associated with ARDS. The objective of this study was to characterize the lung injury, specifically the endogenous surfactant system in septic adult rats. Sepsis was induced in male Sprague-Dawley rats by cecal ligation and perforation and resulted in significant increases in heart rates, respiratory rates, and lactate levels along with positive blood cultures in septic animals compared with a sham control group. Two distinct septic groups were developed, a septic group and a sepsis with lung injury (septic+LI) group. The septic group had no significant differences in oxygenation compared with the sham group, whereas the septic+LI group had significantly lower PaO2 and higher A-a gradient values compared to both the sham and septic groups. The total surfactant pool size was significantly lower in the septic+LI group compared with the sham group. The small surfactant aggregate to large surfactant aggregate ratio was significantly lower in the septic group and was further reduced in the septic+LI group. There were also significantly higher levels of surfactant protein A (SP-A) in both septic and septic+LI groups compared to the sham group. These results demonstrated that the endogenous surfactant system was altered in systemic sepsis without lung dysfunction and is further altered when a lung injury is present.

UKCCSG study of accelerated radiotherapy for pediatric brain stem gliomas. United Kingdom Childhood Cancer Study Group

PURPOSE

Between 1991 and 1994, the United Kingdom Childhood Cancer Study Group (UKCCSG) conducted a multicenter study to assess the efficiency and tolerability of accelerated radiotherapy in children with a diagnosis of poor-prognosis brain stem glioma.

METHODS AND MATERIALS

Patients eligible for study were those aged 3-16 years with tumors arising in the pons, medulla, or midbrain, not previously treated with radiotherapy or chemotherapy. Histologic confirmation was not mandatory, but computed tomography or magnetic resonance imaging and clinical findings had to be typical, and patients were selected with short prediagnosis symptom history (<3 months), cranial nerve palsies or long tract signs, and intrinsic diffuse lesions on scanning. The treatment dose was 48.6 Gy in 27 fractions, increased to 50.4 Gy in 28 fractions in January 1992, delivered twice daily (except weekends) with an interfraction interval of at least 8 h. Between January 1991 and July 1994, 28 available patients were recruited: 15 boys and 13 girls with ages ranging between 3 and 13 years (median 6).

RESULTS

After treatment, neurologic improvement sustained for a period of at least 6 weeks without steroids was reported in 13 children (46%). On central review of postradiotherapy imaging, 50% of children showed evidence of partial response, but none exhibited a complete response. A further six patients (22%) had stable disease. The median survival time was 37 weeks (8.5 months); 1-year survival was 32%, and 2-year survival 11%. The pattern of relapse was local in all 26 patients who died of their disease; 1 patient had evidence of leptomeningeal seeding. Acute radiation morbidity was minimal, with only three patients (11%) exhibiting mild toxicity. No evidence of radiation-induced necrosis was found radiologically or histologically at postmortem. Ability to withdraw steroids following radiotherapy was the single most important prognostic variable in our study.

CONCLUSION

The results of this study are comparable to previous outcomes of studies with conventional and hyperfractionated radiotherapy in poor-prognosis brain stem glioma. The fractionation regimen was shown to be tolerable with an acceptable morbidity profile. However, further research is required to improve the poor prognosis of these unfortunate children.

Organization and development of facial motor neurons in the kreisler mutant mouse

The adult facial nerve contains the axons from two populations of efferent neurons. First, the branchiomotor efferent neurons that innervate the muscles of the second arch. These neurons project out of the hindbrain in the motor root and form the facial motor nuclei. Second, the preganglionic efferent neurons that innervate the submandibular and pterygopalatine ganglia. These neurons project from the hindbrain via the intermediate nerve and form the superior salivatory nucleus. The motor neurons of the facial nerve are known to originate within rhombomeres 4 and 5. In the kreisler mouse mutant there is a specific disruption of the hindbrain rhombomeres 5 and 6 appear to be absent. To investigate changes in the organization of the facial motor neurons in this mutant, we have used lipophilic dyes to trace the facial motor components both retrogradely and anterogradely. As expected, facial motor neurons are missing from rhombomere 5 in this mutant. In addition, the loss of these neurons correlates with the specific loss of the superior salivatory nucleus. In contrast, the branchiomeric neurons, that originate in rhombomere 4, appear to develop normally. This includes the caudal migration of their cell bodies forming the genu of the facial nerve. Our studies confirm that rhombomeres are critical to hindbrain development and that they are the fundamental unit at which motor neurons are specified.