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Adenylosuccinate lyase deficiency in a Malaysian patient, with novel adenylosuccinate lyase gene mutations

Chen BC, McGown IN, Thong MK, Pitt J, Yunus ZM, Khoo TB, et al.

J Inherit Metab Dis, 2010 Dec;33 Suppl 3:S159-62.
PMID: 20177786 DOI: 10.1007/s10545-010-9056-z

Most cases of adenylosuccinate lyase (ADSL OMIM 103050) deficiency reported to date are confined to the various European ethnic groups. We report on the first Malaysian case of ADSL deficiency, which appears also to be the first reported Asian case. The case was diagnosed among a cohort of 450 patients with clinical features of psychomotor retardation, global developmental delay, seizures, microcephaly and/or autistic behaviour. The patient presented with frequent convulsions and severe myoclonic jerk within the first few days of life and severe psychomotor retardation. The high performance liquid chromatography (HPLC) profile of the urine revealed the characteristic biochemical markers of succinyladenosine (S-Ado) and succinyl-aminoimidazole carboximide riboside (SAICAr). The urinary S-Ado/SAICAr ratio was found to be 1.02 (type I ADSL deficiency). The patient was compound heterozygous for two novel mutations, c.445C > G (p.R149G) and c.774_778insG (p.A260GfsX24).

Matched MeSH terms: Adenosine Monophosphate/deficiency; Adenylosuccinate Lyase/deficiency*
Epstein-Barr virus latent membrane protein-1 oncogene deletions: correlations with malignancy in Epstein-Barr virus--associated lymphoproliferative disorders and malignant lymphomas

Kingma DW, Weiss WB, Jaffe ES, Kumar S, Frekko K, Raffeld M

Blood, 1996 Jul 01;88(1):242-51.
PMID: 8704180

LMP-1, an Epstein-Barr viral (EBV) latency protein, is considered a viral oncogene because of its ability to transform rodent fibroblasts in vivo and render them tumorigenic in nude mice. In human B cells, EBV LMP-1 induces DNA synthesis and abrogates apoptosis. LMP-1 is expressed in EBV-transformed lymphoblastoid cell lines, nasopharyngeal carcinoma (NPC), a subset of Hodgkin's disease (HD), and in EBV-associated lymphoproliferative disorders (EBV-LPDs). Recently, focused deletions near the 3' end of the LMP-1 gene (del-LMP-1, amino acids 346-355), in a region functionally related to the half-life to the LMP-1 protein, have been reported frequently in human immunodeficiency virus (HIV)-associated HD (100%) and EBV+ Malaysian and Danish peripheral T-cell lymphomas (100%, 61% respectively), but less frequently in cases of HD not associated with HIV (28%, 33%) and infectious mononucleosis (33%). To further investigate the potential relationship of del-LMP-1 to EBV-LPDs associated with immunosuppression or immunodeficiency, we studied 39 EBV-associated lymphoproliferations (10 benign, 29 malignant) from four distinct clinical settings: posttransplant (4 malignant, 1 reactive); HIV+ (18 malignant, 2 reactive); nonimmunodeficiency malignant lymphoma (ML) (7 cases); and sporadic EBV infection with lymphoid hyperplasia (7 cases). The presence of EBV within lymphoid cells was confirmed by EBV EBER1 RNA in situ hybridization or by polymerase chain reaction (PCR) analysis. EBV strain type and LMP-1 deletion status were determined by PCR. EBV strain types segregated into two distinct distributions: HIV+ (9 A; 11 B) and non-HIV (19 A, 0 B), consistent with previous reports. Overall, del-LMP-1 were found in 1 of 5 (20%) Burkitt lymphomas (BL); 17 of 24 (71%) aggressive non-Hodgkin's lymphoma (agg-NHL), and 2 of 10 (20%) reactive lymphoid proliferations. Of the agg-NHLs, del-LMP-1 were present in 4 of 4 PT-ML (100%); 10 of 15 HIV+ ML (67%); and 3 of 5 nonimmunodeficiency malignant lymphoma (ML, 60%). A total of 2 of 7 (28%) sporadic EBV-associated lymphoid hyperplasias contained a del-LMP-1. All del-LMP-1 were identical by DNA sequence analysis. No correlation was identified between the presence of del-LMP-1 and the EBV strain type observed. The high incidence of del-LMP-1 observed in agg-NHLs (71%), in contrast to the relatively low incidence observed in reactive lymphoid proliferations (28%), suggests that the deleted form may be preferentially selected in lymphomatous processes. All posttransplant agg-NHLs contained a del-LMP-1, and a similar frequency of del-LMP-1 was observed in both HIV-associated ML (66%) and nonimmunodeficiency ML (60%), suggesting that impairment of immune function alone is not a requirement for the expansion of malignant cells infected by EBV stains containing the deleted LMP-1 gene.

Matched MeSH terms: Viral Matrix Proteins/deficiency*
Fulltext The extended clinical phenotype of 64 patients with dedicator of cytokinesis 8 deficiency

Engelhardt KR, Gertz ME, Keles S, Schäffer AA, Sigmund EC, Glocker C, et al.

J Allergy Clin Immunol, 2015 Aug;136(2):402-12.
PMID: 25724123 DOI: 10.1016/j.jaci.2014.12.1945

BACKGROUND: Mutations in dedicator of cytokinesis 8 (DOCK8) cause a combined immunodeficiency (CID) also classified as autosomal recessive (AR) hyper-IgE syndrome (HIES). Recognizing patients with CID/HIES is of clinical importance because of the difference in prognosis and management.
OBJECTIVES: We sought to define the clinical features that distinguish DOCK8 deficiency from other forms of HIES and CIDs, study the mutational spectrum of DOCK8 deficiency, and report on the frequency of specific clinical findings.
METHODS: Eighty-two patients from 60 families with CID and the phenotype of AR-HIES with (64 patients) and without (18 patients) DOCK8 mutations were studied. Support vector machines were used to compare clinical data from 35 patients with DOCK8 deficiency with those from 10 patients with AR-HIES without a DOCK8 mutation and 64 patients with signal transducer and activator of transcription 3 (STAT3) mutations.
RESULTS: DOCK8-deficient patients had median IgE levels of 5201 IU, high eosinophil levels of usually at least 800/μL (92% of patients), and low IgM levels (62%). About 20% of patients were lymphopenic, mainly because of low CD4(+) and CD8(+) T-cell counts. Fewer than half of the patients tested produced normal specific antibody responses to recall antigens. Bacterial (84%), viral (78%), and fungal (70%) infections were frequently observed. Skin abscesses (60%) and allergies (73%) were common clinical problems. In contrast to STAT3 deficiency, there were few pneumatoceles, bone fractures, and teething problems. Mortality was high (34%). A combination of 5 clinical features was helpful in distinguishing patients with DOCK8 mutations from those with STAT3 mutations.
CONCLUSIONS: DOCK8 deficiency is likely in patients with severe viral infections, allergies, and/or low IgM levels who have a diagnosis of HIES plus hypereosinophilia and upper respiratory tract infections in the absence of parenchymal lung abnormalities, retained primary teeth, and minimal trauma fractures.

Matched MeSH terms: Guanine Nucleotide Exchange Factors/deficiency*
The artificial loss of Runx1 reduces the expression of quiescence-associated transcription factors in CD4(+) T lymphocytes

Wong WF, Kohu K, Nagashima T, Funayama R, Matsumoto M, Movahed E, et al.

Mol Immunol, 2015 Dec;68(2 Pt A):223-33.
PMID: 26350416 DOI: 10.1016/j.molimm.2015.08.012

The Runx1 transcription factor cooperates with or antagonizes other transcription factors and plays essential roles in the differentiation and function of T lymphocytes. Previous works showed that Runx1 is expressed in peripheral CD4(+) T cells which level declines after T cell receptor (TCR) activation, and artificial deletion of Runx1 causes autoimmune lung disease in mice. The present study addresses the mechanisms by which Runx1 contributes to the maintenance of peripheral CD4(+) T cell quiescence. Microarray and quantitative RT-PCR analyses were employed to compare the transcriptome of Runx1 -/- CD4(+) T cells to those of unstimulated and TCR-stimulated Runx1 +/- cells. The results identified genes whose expression was modulated similarly by Runx1 deletion and TCR activation. Among them, genes encoding cytokines, chemokines, and Jak/STAT signaling molecules were substantially induced. In Runx1-deleted T cells, simultaneous increases in Il-17A and Rorγc, a known master gene in TH17 differentiation, were observed. In addition, we observed that the loss of Runx1 reduced the transcription of genes encoding quiescence-associated transcription factors, including Foxp1, Foxo1, and Klf2. Interestingly, we identified consensus Runx1 binding sites at the promoter regions of Foxp1, Foxo1, and Klf2 genes, which can be enriched by chromatin immunoprecipitation assay with an anti-Runx1 antibody. Therefore, we suggest that Runx1 may activate, directly or indirectly, the expression of quiescence-associated molecules and thereby contribute to the maintenance of quiescence in CD4(+) T cells.

Matched MeSH terms: Core Binding Factor Alpha 2 Subunit/deficiency
Current trends in morbidity and mortality of children in Malaysia

Lin, Hai Peng, Mohd Sham Kasim

Malaysian Journal of Child Health, 1997;9(2):104-132.
MyJurnal

Malaysia is a rapidly developing country with a very young population, about 36% of which are below the age of 15 years. The standard of child health has improved greatly. However, there are great changes in the morbidity and mortality patterns of childhood diseases relating mainly to an improved standard of living; availability of safe water supply and adequate sanitary latrines; a higher literacy rate; rapid industrialisation and urban migration. The infant mortality rate has droppedfrom 50.1 per 1,000 livebirths in 1986 to 10.4 in 1995, and similar trends apply also to neonatal, perinatal and toddler mortality rates. Nevertheless, current major child health problems are those relating to events in the perinatal period and to infections. Despite improvements in the standard of neonatal care with the use ofhigh technology, the commonest cause of certified deaths still occur in the neonatal period. A rapid and inexpensive screening test for G6PD deficiency, a disease present in 2-3% of the population, is now widely available and, together with the use of phototherapy is largely responsible for the declining incidence of kernicterus in the country. Infections remain an important cause of morbidity and mortality although their patterns have changed. The very high (>95%) WHO-EPI-vaccines coverage rate is linked to the great reduction in the incidence of diphtheria, pertussis, tetanus, poliomyelitis and measles. Childhood tuberculosis is less common now, with about 250 - 300 reported cases per year and TB meningitis is rare with about 30-40 reported cases/year. The hepatitis B carrier rate is high (5%) and the introduction of routine newborn hepatitis B vaccination in 1989 is expected to have a positive impact as is the immunisation of young girls against rubella introduced in 1985 in reducing the incidence of congenital rubella syndrome. The incidence of malaria has declined but remains prevalent in the interiors of PeninsularMalaysia and in Sabah and Sarawak. Filariasis is largely under control. Unfortunately, despite great efforts at mosquito control, dengue virus infection remains a major problem with thousands of cases reported every year. Children are most susceptible to dengue haemorrhagic fever with many dying from the shock syndrome. The incidence of acute gastroenteritis has also dropped with most cases being due to a viral aetiology. Acute respiratory infections, mostly viral in origin, account for most attendances at paediatric outpatient services. Although staphylococcal and streptococcal impetigo and pneumonia are common, the incidence of streptococcal related diseases like rheumatic fever and acute glomendonephritis is rapidly declining. The nutritional status of children has improved in tandem with the rise in the standard of living, but subclinical malnutrition is prevalent, particularly among urban squatters and the rural poor. There is a disturbing decline in breastfeeding among urban working mothers. Poor weaning practices and food habits are responsible for the common occurrence of nutritional anaemia (5%) among infants and young children. Greater prosperity, rapid industrialisation and urbanisation have resulted in changes in the childhood disease pattern where non-communicable diseases assume greater importance as the problems of malnutrition and infection are gradually overcome. Road traffic accidents are a major killer and home accidents, largely preventable, are an important cause of morbidity and mortality. Childhood cancer, with about 550 new cases a year, is an important cause of death beyond infancy. Major congenital malformations, with a 1% prevalence rate, cause much ill-health. Thalassaemia is a particularly common genetic disease with fl thalassaemia gene frequency of about 5%. The prevalence of asthma is increasing, with a rate of 13.9% in the Kiang Valley but the prevalence of asthma-related symptoms is much higher. Physical, sexual child abuse and neglect, abandoned babies, substance abuse are but signs of stress of modern city living and peoples inability to cope with it. Although the general standard of child health has greatly improved, there are several states where it is still not satisfactory. In Sabah where there is a large illegal immigrant population, the infant mortality and infection rates are relatively high. In Kelantan and Trengganu, it is common for parents to refuse permission for a lumbar puncture required to treat meningitis. Other still deeply entrenched, culturally-related adverse health practices include : a fatalistic attitude to illness; a preference for traditional practitioners of medicine resulting in late treatment; and 'doctor-hopping' with unrealistic expectations of 'instant cure'. Childhood illnesses that are uncommon in Malaysia include: cystic fibrosis, coeliac disease, ulcerative colitis, Crohns disease, Sudden Infant Death Syndrome, Encopresis, enuresis and epiglottitis due to Haemophilus Influen:ae.

Matched MeSH terms: Glucosephosphate Dehydrogenase Deficiency