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Bedlow AJ, Davies EG, Moss AL, Rebuck N, Finn A, Marsden RA. Pyoderma gangrenosum in a child with congenital partial deficiency of leucocyte adherence glycoproteins. Br J Dermatol 1998; 139:1064-7. [PMID: 9990374 DOI: 10.1046/j.1365-2133.1998.02567.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Congenital deficiency of beta 2 integrin leucocyte adhesion molecules is a rare immunodeficiency and is often fatal. Neutrophils are unable to bind to ligands on the endothelium, and so cannot leave the circulation during inflammation or infection. When leucocyte adhesion deficiency (LAD) is caused by abnormally low expression of beta 2 integrins, it is termed LAD type 1. We describe a 5-year-old girl with a history of recurrent bacterial infections since early childhood who developed necrotic skin ulcers resembling pyoderma gangrenosum and a persistent circulating neutrophilia. Histologically, the lesions showed deep ulceration with a diffuse lymphohistiocytic infiltrate, but with a relative sparsity of neutrophils. Subsequent investigation revealed a complete absence of CD11a/CD18 beta 2 integrins on the surface of the patient's neutrophils, confirming the diagnosis of LAD type 1. The ulcers responded to treatment with oral prednisolone and colchicine.
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Richardson MP, Ayliffe MJ, Helbert M, Davies EG. A simple flow cytometry assay using dihydrorhodamine for the measurement of the neutrophil respiratory burst in whole blood: comparison with the quantitative nitrobluetetrazolium test. J Immunol Methods 1998; 219:187-93. [PMID: 9831400 DOI: 10.1016/s0022-1759(98)00136-7] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The neutrophil respiratory burst is essential for the host's ability to kill ingested microorganisms. Several flow cytometric assays have recently been developed to measure this process. These assays are largely unvalidated. In this study a whole blood flow cytometry assay using dihydrorhodamine 123 (DHR) as a substrate was compared with the quantitative nitrobluetetrazolium (NBT) test, an accepted measure of the earliest events in the respiratory burst. Because whole blood is used, the new assay is quicker and simpler than existing flow cytometry assays. Specimens as small as 0.1 ml can be used which makes the assay ideal for use in neonates and young children. There was a high degree of correlation between the DHR assay and the quantitative NBT test (r(s) = 0.76, P < 0.01). It is concluded that the whole blood DHR assay is an accurate and sensitive measure of the respiratory burst.
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Armour DJ, Cairns CJ, Costello I, Riley SJ, Davies EG. The economics of a pharmacy-based central intravenous additive service for paediatric patients. PHARMACOECONOMICS 1996; 10:386-394. [PMID: 10163580 DOI: 10.2165/00019053-199610040-00007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This study was designed to compare the costs of a pharmacy-based Central Intravenous Additive Service (CIVAS) with those of traditional ward-based preparation of intravenous doses for a paediatric population. Labour costs were derived from timings of preparation of individual doses in both the pharmacy and ward by an independent observer. The use of disposables and diluents was recorded and their acquisition costs apportioned to the cost of each dose prepared. Data were collected from 20 CIVAS sessions (501 doses) and 26 ward-based sessions (30 doses). In addition, the costs avoided by the use of part vials in CIVAS was calculated. This was derived from a total of 50 CIVAS sessions. Labour, disposable and diluent costs were significantly lower for CIVAS compared with ward-based preparation (p < 0.001). The ratio of costs per dose [in 1994 pounds sterling] between ward and pharmacy was 2.35:1 (2.51 pounds:1.07 pounds). Sensitivity analysis of the best and worst staff mixes in both locations ranged from 2.3:1 to 4.0:1, always in favour of CIVAS. There were considerable costs avoided in CIVAS from the multiple use of vials; the estimated annual sum derived from the study was 44,000 pounds. In addition, CIVAS was less vulnerable to unanticipated interruptions in work flow than ward-based preparation. CIVAS for children was more economical than traditional ward-based preparation, because of a cost-minimisation effect. Sensitivity analysis showed that these advantages were maintained over a full range of skill mixes. Additionally, significant savings accrued from the multiple use of vials in CIVAS.
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Sharland M, Hodgson J, Davies EG, Booth J, Jeffery S. Enteroviral pharyngitis diagnosed by reverse transcriptase-polymerase chain reaction. Arch Dis Child 1996; 74:462-3. [PMID: 8669969 PMCID: PMC1511539 DOI: 10.1136/adc.74.5.462] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The role of enteroviruses in childhood pharyngitis was investigated using enteroviral specific reverse transcriptase-polymerase chain reaction (RT-PCR). Viral/bacterial throat swabs were taken from 50 children with acute pharyngitis and 26 controls. A positive culture was identified in only 26% of children with pharyngitis (adenovirus 10%, group A streptococci 2%), and none of the controls. Enteroviral RT-PCR was positive in 8% of the pharyngitis group and none of the controls. Enteroviruses are an important cause of pharyngitis in childhood.
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Hamblin M, Marsh JC, Lawler M, McCann SR, Wickham N, Dunlop L, Ball S, Davies EG, Hale G, Waldmann H, Gordon-Smith EC. Campath-1G in vivo confers a low incidence of graft-versus-host disease associated with a high incidence of mixed chimaerism after bone marrow transplantation for severe aplastic anaemia using HLA-identical sibling donors. Bone Marrow Transplant 1996; 17:819-24. [PMID: 8733704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have evaluated the effect of in vivo Campath-1G on engraftment and GVHD in 23 patients with severe aplastic anaemia transplanted from HLA-identical sibling donors. In 14 patients Campath 1g was given pre-transplant for up to 9 days in an attempt to overcome graft rejection (group 1). In nine patients Campath-1G was given pre-transplant, but also continued post-transplant until day +5 to reduce GVHD (group 2). There were three patients with late graft failure in group I following initial neutrophil engraftment, and four cases of grade II+ GVHD. In group II, two patients had early graft failure (no take), and there were no cases of acute GVHD out of seven evaluable patients. One patient in group I developed chronic GVHD of the liver, and two patients (one in each group) had transient localised chronic GVHD. PCR of short tandem repeats was used to evaluate chimaeric status in 13 patients. Of 11 patients with initial neutrophil engraftment, only one had 100% donor haemopoiesis at all times. The remaining patients had either transient mixed chimaerism or persistence of recipient (< 20%) cells. We conclude that in vivo Campath-1G is associated with a high incidence of mixed chimaerism which tips the balance away from GVHD but towards graft rejection.
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Kelly AJ, Bailey R, Davies EG, Pearcy R, Winson IG. An audit of early wound infection after elective orthopaedic surgery. JOURNAL OF THE ROYAL COLLEGE OF SURGEONS OF EDINBURGH 1996; 41:129-31. [PMID: 8632389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The incidence of early post-operative wound infection was studied prospectively in 1053 patients undergoing elective orthopaedic procedures over a 3-month period. The study was repeated in 1131 patients a year later, 6 months after the hospital had moved to new premises. A clinical definition of wound infection identified disturbingly high sepsis rates. A total of 44% of all infections occurred after discharge from hospital. Despite the large sample, there was no significant difference in the rate of early wound infection between the two periods (7.85 and 6.82%). There was no significant difference in infection rates between theatres with and without laminar air flow. In the majority (35 out of 53) of minor infections, bacteriological confirmation was not available because no microbiological specimens were received. Conversely, there were five negative swabs out of 16 wounds defined clinically as major infections. We conclude that, where the rate of bacteriological confirmation of wound infection is low, the use of a clinical definition gives higher audited sepsis rates. Large audit samples are required to demonstrate differences as a result of a changed practice.
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Booth MJ, Boriskin YS, Booth JC, Carrington D, Sharland M, Davies EG. Evaluation of a capillary polymerase chain reaction procedure for the rapid detection of HIV-1 DNA in blood. AIDS 1996; 10:230-1. [PMID: 8838714 DOI: 10.1097/00002030-199602000-00016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Biswas S, Friedland JS, Remick DG, Davies EG, Sharland M. Elevated plasma interleukin 8 in respiratory syncytial virus bronchiolitis. Pediatr Infect Dis J 1995; 14:919. [PMID: 8584330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Bedford Russell AR, Davies EG, Gibson FM, Gordon-Smith EC. The in vitro effects of granulocyte and granulocyte-macrophage colony-stimulating factor on interleukin-3-dependent proliferation of human neonatal circulating progenitor cells. Pediatr Res 1995; 37:630-3. [PMID: 7541523 DOI: 10.1203/00006450-199505000-00013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Recombinant human granulocyte (rhG) colony-stimulating factor (CSF) and recombinant human granulocyte-macrophage (rhGM) CSF have been used to enhance neonatal neutrophil host defense. We aimed to determine the comparative efficacy of rhG-CSF and rhGM-CSF in increasing numbers of granulocyte colony-forming unit (CFU-G) and granulocyte-macrophage colony-forming unit (CFU-GM) in recombinant human (rh) IL-3-dependent cultures of human neonatal circulating hematopoietic progenitor cells, including cells from infants born to hypertensive mothers. We also investigated the relationship between fractional increase in CFU-G and endogenous plasma concentration of G-CSF. Circulating mononuclear cells were harvested from 25 neonates, and standard short-term assays in semisolid agar were established in the presence of rhIL-3 alone, rhIL-3 with rhG-CSF and rhGM-CSF, and both rhG-CSF and rhGM-CSF. CFU-G and CFU-GM were counted on d 14. Total colony number and CFU-G were significantly greater in cultures supplemented with rhG-CSF, with or without rhGM-CSF (p < 0.001 and p < 0.0005 for total colony number and CFU-G, respectively), when compared with cultures with rhIL-3 alone. Progenitor cells from three infants born to hypertensive mothers responded similarly. Total colony numbers and CFU-G were not increased by rhGM-CSF alone or by addition of rhGM-CSF to rhG-CSF; however, the proportions of CFU-GM were (p < 0.05 and p < 0.001, respectively, compared with rhIL-3 alone).(ABSTRACT TRUNCATED AT 250 WORDS)
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Levin M, Newport MJ, D'Souza S, Kalabalikis P, Brown IN, Lenicker HM, Agius PV, Davies EG, Thrasher A, Klein N. Familial disseminated atypical mycobacterial infection in childhood: a human mycobacterial susceptibility gene? Lancet 1995; 345:79-83. [PMID: 7815885 DOI: 10.1016/s0140-6736(95)90059-4] [Citation(s) in RCA: 171] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Inherited defects in specific components of the immune system have provided many clues to the immunological mechanisms underlying resistance to microbial infection. We report a familial immune defect predisposing to disseminated atypical mycobacterial infection in childhood. 6 children with disseminated atypical mycobacterial infection and no recognised form of immunodeficency were identified. Four, including two brothers, come from a village in Malta, and two are brothers of Greek Cypriot origin. They presented with fever, weight loss, lymphadenopathy, and hepatosplenomegaly. They had anaemia and an acute phase response. A range of different mycobacteria (Mycobacterium fortuitum, M chelonei, and four strains of M avium intracellulare complex) were isolated. Treatment with multiple antibiotics failed to eradicate the infection, although treatment with gamma interferon was associated with improvement. Three have died and the surviving children have chronic infection. Tumour necrosis factor-alpha production in response to endotoxin and gamma-interferon was found to be defective in affected patients and their parents. T-cell proliferative responses to mycobacterial and recall antigens were reduced in parents of affected children and gamma-interferon production was diminished in the affected patients and their parents. Clinical and immunological features suggest that these patients are phenotypically similar to Lsh/Ity/Bcg susceptible mice. Understanding of this defect may provide insights into the mechanisms responsible for susceptibility to mycobacteria.
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Russell AR, Davies EG, Ball SE, Gordon-Smith E. Granulocyte colony stimulating factor treatment for neonatal neutropenia. Arch Dis Child Fetal Neonatal Ed 1995; 72:F53-4. [PMID: 7538031 PMCID: PMC2528420 DOI: 10.1136/fn.72.1.f53] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
In a pilot study recombinant human granulocyte colony-stimulating factor (rhG-CSF) was administered to 12 neutropenic preterm infants to determine if neonatal neutropenia is secondary to decreased endogenous G-CSF production. Respiratory variables were monitored because of the possible link between inflammatory cells and hyaline membrane disease. All infants showed increased neutrophil counts. The only possible side effect observed was an exacerbation of thrombocytopenia.
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Abstract
Brachyolmia is a form of spondylodysplasia that has not to the authors' knowledge been described in the UK. It may be a cause of short stature that is currently unrecognised. A case of an 11 year old boy with clinical, radiographic, and eye findings consistent with Toledo type brachyolmia is reported.
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Martin K, Davies EG, Axford JS. Fever of unknown origin in childhood: difficulties in diagnosis. Ann Rheum Dis 1994; 53:429-33. [PMID: 7944613 PMCID: PMC1005364 DOI: 10.1136/ard.53.7.429] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
We have described a child with systemic onset juvenile chronic arthritis who presented initially with fever of unknown origin. Treatment of a presumed infection led to a severe allergic response with Stevens-Johnson syndrome, renal failure and DIC. This reaction obscured the features of the underlying disease and delayed the diagnosis.
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Abstract
A 4 year old girl treated with a standard chemotherapy protocol for acute lymphoblastic leukaemia developed hepatic candidosis during the consolidation phase. This relapsed after a prolonged course of amphotericin B and flucytosine. An eight week course of liposomal amphotericin produced a marked clinical improvement which was sustained for one year. A subsequent relapse was associated with transformation to myelodysplastic leukaemia.
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Russell AR, Davies EG, McGuigan S, Scopes GJ, Daly S, Gordon-Smith EC. Plasma granulocyte-colony stimulating factor concentrations ([G-CSF]) in the early neonatal period. Br J Haematol 1994; 86:642-4. [PMID: 7519038 DOI: 10.1111/j.1365-2141.1994.tb04798.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We studied G-CSF concentrations ([G-CSF]) at birth and their relationship with neutrophil count, incidence of infection, gestational age, labour, and the presence of maternal pregnancy-induced hypertension. Plasma [G-CSF] were significantly elevated in babies with suspected infection and in those of hypertensive mothers, compared to healthy babies delivered by elective caesarian section (median [range] = 3101 [75- > 5000] pg/ml and 153 [45-857] pg/ml versus 32 [11-266] pg/ml; P < 0.0001); and were unrelated to neutrophil count and gestational age. Initial high concentrations (> 100 pg/ml) declined by 7 d (P < 0.0001).
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Martin K, Sharland M, Davies EG. Encephalopathy associated with Salmonella enteritidis infection. SCANDINAVIAN JOURNAL OF INFECTIOUS DISEASES 1994; 26:486-8. [PMID: 7984983 DOI: 10.3109/00365549409008624] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A 15-year-old boy who presented with a short history of a diarrhoeal illness associated with encephalopathic features is described. Salmonella enteritidis phage type 4 was cultured from his stool. Although encephalopathy in the absence of CNS infection or electrolyte disturbance is well described in enteric fever, it is very rare in infections with non-typhoidal Salmonella serotypes and has not previously been described in association with S. enteritidis infection.
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Connolly AA, Rowe-Jones J, Leighton SE, Ball SE, Davies EG, Moore-Gillon V. Pseudomonal supraglottitis occurring in a patient with profound neutropenia secondary to virus-associated haemophagocytic syndrome. J Laryngol Otol 1992; 106:739-40. [PMID: 1328436 DOI: 10.1017/s0022215100120742] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We present a case of virus-associated haemophagocytic syndrome following Epstein-Barr virus infection in which a fulminant pseudomonal supraglottitis developed. Increasingly, unusual pathogens have been found in immunocompromised patients. This is the first reported case of pseudomonal supraglottitis.
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Davies EG, Sullivan PM, Fitzpatrick M, Kohner EM. Validation and reproducibility of bidirectional laser Doppler velocimetry for the measurement of retinal blood flow. Curr Eye Res 1992; 11:633-40. [PMID: 1521464 DOI: 10.3109/02713689209000736] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Bidirectional laser Doppler velocimetry (BLDV) for the measurement of retinal blood flow was validated in six anaesthetised minipigs, by comparing BLDV derived results with those obtained using radioactively labelled microspheres (RLM). The mean velocity of blood (Vmean) was calculated from the maximum red blood cell velocity measured by BLDV. Volumetric flow rate was determined from Vmean and vessel diameter, measure from monochromatic fundus photographs. Total retinal blood flow (TRBF) was calculated by summating flow values obtained for each retinal vein draining into the optic disc. A significant correlation was found between the TRBF results obtained by the two techniques (r = 0.99, p less than 0.001). The BLDV results were between 3-35 microliters/min lower than the corresponding RLM results (p = 0.05). Values of 57 +/- 24 microliters/min and 76 +/- 34 microliters/min were obtained for TRBF using the BLDV and RLM techniques respectively. Reproducibility studies with BLDV were also performed in six anaesthetised pigs over three hours and in six normal human volunteers over two hours and two weeks. No significant difference between measurements was found with time. Ninety five percent confidence limits of +/- 9.8% for the six pigs and +/- 8.9% for the six human volunteers were found for measurements on the same day and at two weeks. We conclude that with a sample size of six, changes in flow of approximately 20% can be detected using BLDV and monochromatic fundus photography.
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Davies EG, Moxon ER, Candy DC, Levin M, Levinsky RJ. Training in infectious diseases. JOURNAL OF THE ROYAL COLLEGE OF PHYSICIANS OF LONDON 1991; 25:181. [PMID: 2066932 PMCID: PMC5377218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Caldwell G, Davies EG, Sullivan PM, Morris AH, Kohner EM. A laser Doppler velocimetry study of the effect of hypoglycaemia on retinal blood flow in the minipig. Diabetologia 1990; 33:262-5. [PMID: 2198185 DOI: 10.1007/bf00403318] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effect of acute hypoglycaemia (plasma glucose less than 2.2 mmol/l) on retinal venous blood flow in the minipig has been determined using bidirectional laser Doppler velocimetry and red free retinal photography. In six pigs the mean flow in a retinal vein increased from 19.3 (+/- 2.8 SEM) microliters/min to 29.7 (+/- 7.5) microliters/min during hypoglycaemia (p less than 0.05) with a return to 18.6 (+/- 3.6) microliters/min when euglycaemia was restored. Retinal blood flow is affected by hypoglycaemia or its haemodynamic consequences.
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Mok Q, Curley R, Tolmie JL, Marsden RA, Patton MA, Davies EG. Restrictive dermopathy: a report of three cases. J Med Genet 1990; 27:315-9. [PMID: 2352259 PMCID: PMC1017083 DOI: 10.1136/jmg.27.5.315] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We report three infants with a rare syndrome of restrictive dermopathy, in which rigidity of the skin at birth is associated with characteristic facial anomalies, generalised arthrogryposis, bony abnormalities, and lung hypoplasia. The skin has a distinctive pathology with compaction of the dermal collagen and fibrosis of the subcutaneous tissue. The inheritance is likely to be autosomal recessive and the condition appears to be fatal in the early neonatal period.
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Davies EG, Hyer SL, Kohner EM. Macular blood flow response to acute reduction of plasma glucose in diabetic patients measured by the blue light entoptic technique. Ophthalmology 1990; 97:160-4. [PMID: 2326003 DOI: 10.1016/s0161-6420(90)32610-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The response of retinal blood flow to acute reduction in plasma glucose levels was studied in 20 poorly controlled type I diabetic patients. Perifoveal flow velocity was determined, using the blue-light entoptoscope, and arterial calibers measured, using a computer-aided digitizing system. Mean plasma glucose level was lowered from 17.7 +/- 4 to 7.0 +/- 1 mmol/l after a subcutaneous insulin infusion and measurements taken at both glucose levels. The autoregulatory change induced by breathing 60% oxygen at the two plasma glucose levels also was compared. Mean flow velocities were 0.54 +/- 0.28 mm/sec at a high plasma glucose level compared with 0.55 +/- 0.32 mm/sec at a low plasma glucose level, whereas hyperoxia reduced these by 16.58 and 16.71%, respectively. No significant difference in the responses of arterial diameters to hyperoxia between the two glucose levels was found. The authors conclude that acute reduction in plasma glucose level in this group of patients is not associated with significant changes in macular blood flow or in alteration in autoregulation.
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