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M X Wang

Publications and source records attributed to M X Wang.

At least 37 records · Page 2Linked to original sources
PubMed1998

Mutation hot spots in 5q31-linked corneal dystrophies.

Mutations in the BIGH3 gene on chromosome 5q31 cause four distinct autosomal dominant diseases of the human cornea: granular (Groenouw type I), Reis-Bücklers, lattice type I, and Avellino corneal dystrophies. All four diseases are characterized by both progressive accumulation of corneal deposits and eventual loss of vision. We have identified a specific recurrent missense mutation for each type of dystrophy, in 10 independently ascertained families. Genotype analysis with microsatellite markers surrounding the BIGH3 locus was performed in these 10 families and in 5 families reported previously. The affected haplotype could be determined in 10 of the 15 families and was different in each family. These data indicate that R555W, R124C, and R124H mutations occurred independently in several ethnic groups and that these mutations do not reflect a putative founder effect. Furthermore, this study confirms the specific importance of the R124 and R555 amino acids in the pathogenesis of autosomal dominant corneal dystrophies linked to 5q.

Chromosome Mapping↗
PubMed1997

[Clinical study on jianfei pill in preventing and treating recurrence of infantile asthma].

OBJECTIVE: Further explore on preventing and treating recurrence of infantile asthma with TCM method and its mechanism. METHODS: Using Jianfei Pill (JFP) which was prepared according to the therapeutic principle of strengthening the body resistance to consolidate the constitution and promoting blood circulation to remove obstruction in the channels in treating 56 patients suffering from asthma. Their pulmonary functions were observed. RESULTS: A total effective rate of 91.1% was shown in JFP group, which was higher than that of the control group (60%), P < 0.01. In comparison with the control group, the level of serum IgA, IgG and E-rosette ascend significantly (P < 0.01). The wave amplitude of pulmonary impedance rheogram and right heart index (HI) also increased significantly (P < 0.01), while pulmonary arterial pressure (PPA) and pulmonary vascular resistance (PVR) dropped markedly (P < 0.01). CONCLUSION: JFP might work by means of enhancing the immune function and improving the pulmonary microcirculation to control chronic bronchial inflammation and reduce its reactivity to prevent the relapse of asthma.

Anti-Asthmatic Agents↗
PubMed1996

Familial uveal melanoma, III. Is the occurrence of familial uveal melanoma coincidental?.

OBJECTIVE: To ascertain whether the familial occurrence of uveal melanoma was coincidental in kindreds in which 1 first-degree relative of the proband had also been affected with primary uveal melanoma. PATIENTS: In a series of 4500 patients with primary uveal melanoma, 17 kindreds were identified in which a first-degree relative of the proband had also been affected with primary uveal melanoma. DESIGN: In the 17 families in which a first-degree relative of the proband had been affected, primary uveal melanoma was classified as familial. In the remaining 4483 families, primary uveal melanoma was classified as sporadic. The expected number of affected first-degree relatives of probands for a family was estimated, assuming an incidence rate of 6 cases per million population per year in each type of family. RESULTS: The expected number of affected first-degree relatives was calculated to be 0.81, with an SE of 0.08, compared with 17 observed affected first-degree relatives (P < .001). CONCLUSION: Our study provides strong statistical evidence that occurrence of familial uveal melanoma is not coincidental.

Adolescent↗
PubMed1996

Genetic aspects of uveal melanoma: a brief review.

Uveal melanoma usually occurs sporadically in the absence of obvious genetic predisposing factors. However, in rare patients, there is a suggestion that there may be genetic predisposition. Rare occurrences of familial uveal melanoma are believed to be inherited in an autosomal dominant mode. There are a few clinical conditions that can predispose to or be associated with uveal melanoma, including ocular melanocytosis, neurofibromatosis type I, and familial atypical mole and melanoma syndrome. Nonrandom cytogenetic changes in uveal melanoma are characterized by monosomy 3, trisomy 8, and structural or numerical abnormalities of chromosome 6. Alterations of chromosome 9p are less frequently observed. CDKN2 gene, a cutaneous melanoma predisposition gene, is probably not a uveal melanoma predisposition gene as evidenced by the lack of somatic mutations involving this gene in uveal melanoma samples and the absence of germline mutations in familial uveal melanoma patients. Transgenic mouse models developed using a tyrosinase promoter tagged with a mutated ras gene or SV40-Tag oncoprotein develop retinal pigment epithelium tumors that resemble uveal melanoma. We propose that uveal melanoma cases be categorized on genetic basis according to a new classification system. This classification scheme will help to identify and uniformly categorize uveal melanoma patients with genetic predisposition. Such patients offer unique opportunities for studying the genetic aspects of uveal melanoma and, therefore, appropriate tissue samples should be obtained from them for molecular genetic studies. Further studies are needed to fully understand the genetic aspects of uveal melanoma.

Animals↗
PubMed1995

Epitope specificity of monoclonal anti-beta 2-glycoprotein I antibodies derived from patients with the antiphospholipid syndrome.

beta 2-Glycoprotein I (beta 2GPI) has been identified as a cofactor in the recognition of the phospholipid Ag cardiolipin (CL) by anticardiolipin Ab (aCL) purified from patients with autoimmune diseases. However, there is considerable controversy as to the exact nature of the epitopes to which these Abs are directed. mAb derived from patients with the antiphospholipid syndrome bound to CL only in the presence of beta 2GPI. Synthetic peptides that span the fifth C-terminal domain of beta 2GPI supported the binding of one of the mAbs to CL in a beta 2GPI-free system. These peptides possessed the phospholipid binding sequence Cys281-Lys-Asn-Lys-Glu-Lys-Lys-Cys288. Three of the mAbs bound to beta 2GPI that had been adsorbed on gamma-irradiated microtiter plates. Binding to beta 2GPI was inhibited in a dose-dependent manner by the peptides from the carboxyl-terminal end of beta 2GPI and soluble beta 2GPI, indicating that the mAb bound to peptides and beta 2GPI in free solution. Thus, mAbs derived from patients with the antiphospholipid syndrome have specificity for epitopes on the fifth domain of beta 2GPI. Our results support the idea that beta 2GPI acts as a primary Ag for these Abs.

Adult↗
PubMed1995

Immunization of a rabbit with beta 2-glycoprotein I induces charge-dependent crossreactive antibodies that bind anionic phospholipids and have similar reactivity as autoimmune anti-phospholipid antibodies.

A rabbit immunized with beta 2-glycoprotein I (beta 2-GPI) produced Abs that bind to negatively charged phospholipids and to beta 2-GPI. After affinity purification of the Abs to beta 2-GPI, the dual reactivity could still be detected. Adsorption studies with a phosphatidylserine affinity column depleted phospholipid-reactive Abs, but beta 2-GPI reactivity was retained. The same pattern of reactivity was found with culture supernatants from rabbit anti-beta 2-GPI splenocytes fused with an immortalized rabbit cell line. The reactivity to negatively charged phospholipids is likely to involve ionic interactions, as high ionic strength buffers eliminated binding to anionic phospholipids, but not to beta 2-GPI. Affinity-purified anti-phospholipid (aPL) Abs from four of seven autoimmune patients bound anionic phospholipids in the absence of beta 2-GPI. However, in high ionic strength buffer, this binding was abolished in three patients and significantly reduced in the fourth. In contrast, affinity-purified aPL Abs from seven autoimmune patients bound to beta 2-GPI-coated plates, and binding in high ionic strength buffer was reduced only moderately in three patients. Therefore, autoimmune-type aPL Abs display anti-beta 2-GPI reactivity and charge-dependent binding to anionic phospholipids similar to affinity-purified rabbit anti-beta 2-GPI Abs.

Animals↗
PubMed1995

Recent advances in the molecular genetics of retinitis pigmentosa.

In recent years a rapid development in gene cloning techniques has been seen which has, in part, been responsible for the elucidation of the molecular mechanisms involved in many hereditary diseases. Most noteworthy is the rapid detection of mutations in various genes Most noteworthy is the rapid detection of mutations in various genes associated with various retinal degenerations and disorders. There is an increasing need for ophthalmologists to keep abreast with these new developments to better understand disease processes and recognize new opportunities for the diagnosis and treatment of these conditions. In addition, more recent discoveries in molecular genetics have revealed previously unrecognized associations between different clinical entities that share common gene mutations (gene sharing), as well as distinctly different molecular alterations within the spectrum of what traditionally was believed to be the same disease (locus heterogeneity). These findings will most likely, in the future, invoke the need to redefine disease categories at the molecular level. This article reviews basic molecular genetics useful to ophthalmologists and examines in detail these concepts with regard to one representative hereditary retinal disease--retinitis pigmentosa.

Amino Acid Sequence↗
PubMed1994

Albumin excretory rate in normal and hypertensive pregnancy.

1. The purpose of this study was to determine whether the 24 h urinary albumin excretory rate was increased in the third trimester of normal pregnancy or in pregnant women with hypertension who had 24 h urinary total protein excretion within the normal range. 2. Twenty-four hour urinary creatinine and albumin excretions were determined prospectively in 26 non-pregnant and 115 pregnant women in their third trimester (40 in normal pregnancy, 38 with mild pre-eclampsia, 20 with severe pre-eclampsia, 17 with essential hypertension) in whom urinary total protein excretion was normal. Both the urinary albumin excretion rate and the urinary albumin/creatinine ratio were compared among the groups. The clearance of albumin relative to that of creatinine was also calculated in the hypertensive women and in 14 of the non-pregnant women and nine of the normal pregnant women. 3. The twenty-four hour urinary albumin excretion rate was similar in non-pregnant [8(5-10) mg/day; median (interquartile range)] and normal pregnant [7(6-10) mg/day] women. Women with essential hypertension [6(4-16) mg/day] and mild pre-eclampsia [7(4-10) mg/day] had a urinary albumin excretion rate similar to that of normal pregnant women. Women with severe pre-eclampsia had an urinary albumin excretion rate increased [13(7-32) mg/day] compared with other groups (P < 0.05). The clearance of albumin relative to that of creatinine was elevated significantly only in women with severe pre-eclampsia compared with normal pregnant women (0.00054 versus 0.00012; P < 0.05). Blood pressures were similar among all hypertensive groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Effects of dietary magnesium on blood pressure and vascular lesions in hypertensive rats.

The present study examines the effects of dietary magnesium on the development of hypertension and hypertensive vascular lesions in deoxycorticosterone acetate and salt induced (DOCA-salt) and 2 kidney one clip (2K1C) hypertensive as well as normotensive control rats. Animals received a regular (0.12% Mg), high (0.4% Mg) or low (0.03% Mg) magnesium diet for 6 wks. Dietary magnesium did not alter the growth or blood pressure in control, DOCA-salt and 2K1C rats even though the plasma magnesium concentration was significantly altered by the diets (ANOVA, p < 0.05 in control, DOCA-salt and 2K1C, respectively). Dietary magnesium did not alter the urinary potassium excretion, plasma sodium, potassium, total calcium concentration and plasma renin activity in any group, while the high magnesium diet significantly increased the urinary sodium excretion in DOCA-salt (p < 0.05) but not in control and 2K1C rats when compared with the regular magnesium diet. In histological studies, dietary magnesium did not alter the percentage media area of intramyocardial arteries, or glomerular and renal arterial and arteriolar lesions in DOCA-salt and 2K1C rats. This study suggests that moderate alterations of dietary magnesium do not modify blood pressure in normotensive control, DOCA-salt and 2K1C hypertensive rats, nor do they modify vascular disease in these 2 hypertensive models.

Animals↗
PubMed1994

Endothelin excretion in hypertensive pregnancy. Relationship to glomerular filtration rate, blood pressure, and sodium excretion.

The objective of this study was to determine whether urinary endothelin (ET) excretion is altered in pregnant women with preeclampsia or essential hypertension compared with normal pregnant and nonpregnant women, and whether urinary ET excretion is significantly related to glomerular filtration rate (GFR), blood pressure, or sodium excretion in hypertensive pregnant women. Subjects included 85 hypertensive women in their third trimester (32 with severe preeclampsia, 37 with mild preeclampsia [some of whom may be classified as having "transient (gestational) hypertension" by other classifications], and 16 with essential hypertension), 42 normal third-trimester pregnant women, and 26 normal nonpregnant women. Twenty-four-hour urine ET and creatinine excretion were measured in all women. ET was extracted from urine and measured by radioimmunoassay. Plasma creatinine, serum uric acid and albumin concentrations, and urine protein and sodium excretion were also measured. Twenty-four-hour ET excretion was significantly higher (P < .01) in normal pregnant women (14.7 [9.1 to 20.1] pmol/day; median [interquartile range]) than in nonpregnant women (8.4 [6.4 to 15.2] pmol/day) and was reduced significantly (P < .01) in hypertensive pregnant women (severe preeclampsia: 9.0 [5.5 to 12.4] pmol/day; mild preeclampsia: 7.2 [5.7 to 9.9] pmol/day; essential hypertension: 7.5 [6.4 to 9.4] pmol/day) compared to values for normal pregnant women. Twenty-four-hour urine ET excretion in hypertensive pregnant women was correlated positively but weakly with both creatinine clearance (r = 0.31, P < .01) and urine sodium excretion (r = 0.34, P < .01). Urinary ET excretion is increased in normal pregnancy and reduced from these values in pregnancies complicated with preeclampsia or essential hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed1994

The effects of dietary potassium on vascular and glomerular lesions in hypertensive rats.

The present study examines the effects of dietary potassium (K) on hypertensive glomerular and vascular lesions in deoxycorticosterone acetate and salt induced (DOCA-salt) and two kidney one clip (2K1C) hypertensive as well as normotensive control rats. Animals received a regular (0.28% K), high (1.1% K) or low (0.07% K) potassium diet for 6 weeks. In control rats, low K diet significantly increased systolic blood pressure (SBP) (p < 0.05). In DOCA-salt rats, high K diet did not modify SBP or glomerular and vascular lesions while low K diet significantly increased premature death in these rats. In 2K1C rats, dietary K did not alter the blood pressure, but percentage media area (% media) of intramyocardial arteries, percentage of glomerular lesions, and renal arterial and arteriolar lesion scores were lower in high K diet rats than regular and low K diet rats (p < 0.05). This study is the first demonstration that high K diet can protect against vascular and glomerular lesions in a non salt-loaded hypertensive model. The beneficial effects of dietary K on vascular lesions are at least in part independent of changes in blood pressure, and may be renin related.

Animals↗
PubMed1994

[Efficacy of Phyllanthus spp. in treating patients with chronic hepatitis B].

The efficacy of Phyllanthus amarus produced in india, P. niruri gathered from hainan province and P. urinaria from henan province was assessed in a total of 88 cases of chronic hepatitis B with 11.42 and 35 each. It was shown that P. urinaria had the effect of seroconversion on HBeAg from positive to negative as well as on HBeAb from negative to positive, while the other two herbs had not. In addition none of these three herbs had similar effect on HBsAg.

Adult↗
PubMed1994

[Nucleic acid hybridization technique detection of enterovirus RNA in myocarditis].

Forty five specimens from human myocarditic or myopathic tissues were examined for enteroviruses by in situ hybridization with 2 biotin labelled generic enterovirus probes pCBIII/35 and pCBIII/51. Positive hybridization signals were obtained in 12 samples (26.6%). Enterovirus RNA were obtained in 5 out of these 12 samples (41.7%) by the presence of positive hybridization signals with a coxsackie B3 virus type-specific probe pCBIII/29. The positive hybridization signals were primarily localized within the cytoplasm of single or several myocytes and the myocardial interstitial tissues, and were also occasionally seen within the cytoplasm of endotheliocytes of blood vessels in the myocardium.

Cardiomyopathy, Dilated↗
PubMed1993

Pseudo low penetrance in retinoblastoma. Fortuitous familial aggregation of sporadic cases caused by independently derived mutations in two large pedigrees.

OBJECTIVE: The disparate occurrence of few cases of retinoblastoma in the same extended pedigree confronts us with the unsolved problem of a low-penetrant autosomal-dominant trait vs fortuitous familial aggregation of sporadic cases. Determination as to whether the disease arises from a common inherited mutation or sporadic mutations has important implications for genetic counseling. This is illustrated in this report of two presumed low-penetrant retinoblastoma pedigrees characterized by two distantly affected relatives connected through apparently healthy carriers. DESIGN: We mathematically modeled the inheritance patterns and calculated the a priori relative probabilities of heredity with low penetrance vs chance occurrence of independent mutations for each pedigree. The derived odds clearly show that the disease, which occurred twice in each family, most likely resulted from unrelated mutations. To prove this, extensive DNA testing was conducted, including determination of intragenic RB1 DNA sequence polymorphisms and screening for mutation using the polymerase chain reaction coupled with single-strand conformation polymorphism analysis. PATIENTS: All living key members from both pedigrees were included. RESULTS: Consistent with our initial expectation, there was no common intragenic haplotype or common germ-line mutation that segregated with the disease phenotype in either of these two families. CONCLUSIONS: We therefore conclude that collateral incidence of retinoblastoma in these two pedigrees occurred by chance and not according to autosomal-dominant inheritance with low penetrance. Furthermore, our data provide the first evidence, to our knowledge, that related individuals may have independent mutations involving an identical gene locus, giving rise to an artefactual inheritance pattern.

Child, Preschool↗
PubMed1993

Clinicopathologic associations of anti-endothelial cell antibodies in immunoglobulin A nephropathy and lupus nephritis.

Sera from 45 patients with lupus nephritis (LN), 63 patients with immunoglobulin A nephropathy (IgA N), and 71 glomerulonephritic controls (including 44 mesangial proliferative glomerulonephritis cases, 14 membranous glomerulonephritis cases, and 13 focal segmental glomerular sclerosis cases), and from 33 normal control subjects were tested by a cellular enzyme-linked immunoabsorbent assay for their anti-endothelial cell antibody (AECA) activity. Compared with normal controls, AECAs of the IgG subtype (AECA-IgG) were detected in LN (P < 0.001) and AECAs of the IgA subtype (AECA-IgA) were detected in both IgA N and LN (P = 0.018 and P < 0.001, respectively). Binding activity of AECA to endothelial cells was inhibited by endothelial cell lysate and fibroblast lysate but not by lymphocyte lysate, double stranded-DNA, or bovine serum albumin. Anti-endothelial cell antibody-positive sera also reacted with fibroblasts. In IgA N, associations were found between the presence of AECA and younger age (P = 0.036), proportion of crescents greater than 10% (P = 0.016), fibrin crescents (P = 0.016), and focal and segmental necrotizing lesions (P = 0.047). In LN, inverse associations were found between the presence of AECA and the duration of disease (P = 0.021), elevated serum creatinine levels (P = 0.020), decreased creatinine clearance (P = 0.043), and frequency of chronic renal failure (P = 0.036). Positive associations were observed between the presence of AECA and active lupus (P = 0.017), anti-nuclear antibodies (P = 0.015), and anti-DNA antibodies (P = 0.041). Our results suggest that AECA may be linked with the pathogenesis of LN and IgA N.

Adult↗