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Biomedical subjects

J H Lu

Publications and source records attributed to J H Lu.

62 records · Page 4Linked to original sources
PubMedDate not supplied

Monozygotic twins with chromosome 22q11 microdeletion and discordant phenotypes in cardiovascular patterning.

Monozygotic twins with chromosome 22q11 microdeletions offer an ideal situation to observe the association of microdeletion and disrupted cardiovascular patterning. We report monozygotic twins concordant for 22q11.2 microdeletion but discordant for cardiovascular patterning. Both twins showed identical intracardiac defects including tetralogy of Fallot with pulmonary atresia. Nevertheless, their great vessel patternings were variable. These twins show that the mispatterning of the great vessels may not correlate with intracardiac morphogenesis. The discordant development of the great vessels, especially in the pulmonary vascular system, has clinical significance for prognosis. The phenotypic variability of cardiovascular anomalies seen in 22q11 microdeletion cannot be explained on the basis of genotypic difference.

Abnormalities, Multiple↗
PubMedDate not supplied

Molecular characterization of tetralogy of fallot within Digeorge critical region of the chromosome 22.

The purpose of this study was to determine whether the levels of heterozygosity and microdeletion of specific loci within the DiGeorge critical region (del22q11) are associated with different phenotypes of tetralogy of Fallot (TF). Examinations were conducted on 84 sporadic TF patients and their unaffected parents for del22q11, using the following 9 simple tandem repeat polymorphic microsatellite markers: D22S420, D22S427, D22S941, D22S944, D22S264, D22S311, D22S425, D22S303, D22S257. The microdeletions were confirmed using quantitative PCR with markers TUPLE1, exon 2 of the UFD1L gene, and D22S264; the boundaries of these microdeletions were estimated using genotypic analyses of the unaffected family members. The del22q11 was identified in 14 patients (16.6%). The boundary of the shortest region of deletion overlap (SRO) in these 14 TF patients was identified, proximally using D22S427 and distally using the TUPLE 1 gene. The deletion of exon 2 of the UFD1L gene and TUPLE1 gene was identified in 13 patients (13/14 cases; 93%). The SRO in TF patients with del22q11 was at or close to the ADU breakpoint and centromeric to the UFD1L gene. The level of heterozygosity for the marker D22S944 in TF patients without del22q11 (n = 70) was found to be significantly lower than expected. Overall, this study demonstrated the significantly low level of heterozygosity within DiGeorge critical region in TF patients with or without del22q11. Our results suggest that the genetic factors leading to DiGeorge/velocardiofacial syndrome might also be partly responsible for TF phenotypes.

Adolescent↗
PubMedDate not supplied

[Differential diagnosis of periventricular pseudocysts in the neonatal period].

Periventricular pseudocysts are important sequelae of different noxious insults in the developing brain. Accurate diagnosis of those pathologic entities during early life has therefore become of direct concern to the clinician. When present at birth, they suggest an intrauterine pathology. It has only been with the advent of real-time cranial ultrasonography that subependymal cystic lesions can be detected antemortem. 25 infants were postnatal diagnosed in ultrasound as having periventricular cystic lesions. They belonged to different pathological entities: focal paraventricular pseudocysts (5 cases), periventricular leukomalasia (6 cases), polycystic encephalomalacia (1 case), subependymal pseudocyst (9 cases), connatal viral infection (3 cases), and chromosomal abnormality (1 case). Sequelae of noxious insults in fetal life appear clearly different to those after perinatal injury. Ultrasound findings should be interpreted in combination with obstetric history. Some obstetric complications during 2. trimester can cause paraventrikular cystic formation in fetus. Neurotrophic viral infection and chromosomal abnormalities have also been implicated to produce cystic lesions in this region. This work implies that a wide variety of intracranial pathology is found in newborns with periventricular cystic lesion. Those lesions are not a terminal event in infant, but may be a condition of major clinical importance for further neurologic development.

Cerebral Hemorrhage↗
PubMedDate not supplied

[Schizencephaly].

Schizencephaly is a developmental disorder of the human brain caused by a defect of neuronal migration. We observed a 7 month old african boy suffering from nystagmus and hemiparesis. The neuroimaging reveals a large cleft in cortical and subcortical structures and typical changes of polymicrogyria. In the differential-diagnosis encephaloclastic porencephaly should be considered.

Agenesis of Corpus Callosum↗
PubMedDate not supplied

Data quality of a computerized medical birth registry.

Processed by a computerized medical birth registry system, the birth records of 20,103 deliveries, from February 1992 to February 1993, were digitized with medium registry. From 1 January to 28 February 1993, the original records (n = 2840 cases) of all 10 collaborative hospitals were requested for assessment of data quality. Thirty-six items were scored, data of poor quality was found in eight; acceptable quality in four; and good quality in 28. The feasibility of data transfer by floppy disc and per modem was evaluated. This registry system had effectively shortened data processing time and improved mutual feedback between the data centre and the delivery units. Errors resulting from technical faults originating in the preparation of data for computerization at hospital level could be effectively reduced. The validity of diagnosis remained as the major source of errors.

Birth Certificates↗
PubMedDate not supplied

Detachment of balloon in an infant: a rare complication of balloon pulmonary valvuloplasty.

A 3-month-old infant with severe tetralogy of Fallot underwent percutaneous balloon valvuloplasty. After the successful dilatation, the balloon could not be deflated completely and the partial deflated balloon was totally peeled off from the catheter at the junction of inferior vena cava and right common iliac vein when we attempted to move it out. The skin of the balloon was successfully retrieved with a snared guidewire without sequel.

Catheterization↗
PubMedDate not supplied

DiGeorge syndrome with microdeletion of chromosome 22q11.2: report of one case.

DiGeorge syndrome (DGS) is a congenital anomaly involving developmental defects of the third and fourth pharyngeal pouches. Thymic aplasia or hypoplasia, parathyroid aplasia or hypoplasia, cardiac malformations, and dysmorphic facies are characteristics features. We present a case which had thymic aplasia, hypocalcemia, facial dysmorphism (hypertelorism, low set ears, cleft of soft palate, fish-like mouth and micrognathia) and congenital heart disease (ventricular septal defect, perimembranous type). The T-cell immunologic functions as a percentage of T-cell and phytohemagglutinin stimulation test were within normal range matched with age. Molecular study showed microdeletion of chromosome 22q11.2 by genotype analysis, but chromosome study of high-resolution cytogenetic analysis by G-banding technique was normal. To our knowledge, about 90% of DiGeorge syndrome patients show chromosome abnormalities, most involving chromosome 22 (monosomy of 22q11.2). In the past, most cases were proven by high-resolution cytogenetic analysis or fluorescence in situ hybridization(FISH). We report a case of DGS in Taiwan with microdeletion of chromosome 22q11.2 detected by genotype analysis.

Chromosome Deletion↗