Biomedical subjects

Huiwen Zhang

Publications and source records attributed to Huiwen Zhang.

11 recordsLinked to original sources

PubMed2024

Delayed diagnosis of mild mucopolysaccharidosis type IVA.

BACKGROUND: Mucopolysaccharidosis IVA (MPS IVA) is a lysosomal storage disease caused by biallelic variants in the N-acetylgalactosamine-6-sulfatase (GALNS) gene and is characterized by progressive and multi-system involvements, dominantly with skeletal deformities. A mild form of MPS IVA often presents with atypical symptoms and can go unrecognized for years. METHODS: The diagnosis of MPS IVA was confirmed via GALNS enzyme activity testing in leukocytes. Clinical features were collected. Molecular analysis was performed by next generation sequence and Sanger sequencing of the GALNS gene. The pathogenicity of the deep intron variant was verified by mRNA analyses. RESULTS: Thirteen patients with mild MPS IVA from six families were included. All probands first visit pediatric orthopedists and it took 5.6 years to be diagnosed after the disease onset. The most common symptoms in our series were waddling gait (85%), short neck (69%) and flat feet (62%). Radiologic findings indicated skeletal abnormalities in all patients, especially modification of the vertebral bodies (100%) and acetabular and femoral head dysplasia (100%). Five novel GALNS variants, including c.121-2_121-1insTTTGCTGGCATATGCA, E2 deletion, c.569 A > G, c.898 + 2 T > A, and c.1139 + 2 T > C, were identified. The most common variant, a deep intron variant NM_000512.5: c.121-210 C > T (NM_001323544.2: c.129 C > T, p.G43G), was revealed to result in an 11 bp deletion (c.128_138delGCGATGCTGAG, p.Gly43Aspfs*5) on GALNS mRNA in the GALNS transcript of NM_001323544.2. CONCLUSIONS: This study provides significant insights into the clinical features and molecular characteristics that contribute to the early diagnosis of mild MPS IVA. On the basis of our cohort, orthopedists need to be able to recognize signs and symptoms of mild MPS IVA as well as the molecular and biochemical diagnosis so that an early diagnosis and treatment can be instituted.

Humans↗

PubMed2007

Lysosomal membranes from beige mice contain higher than normal levels of endoplasmic reticulum proteins.

Chediak-Higashi syndrome is characterized by dysfunctional giant organelles of common origin, that is, lysosomes, melanosomes, and platelet dense bodies. Its defective gene LYST encodes a large molecular weight protein whose function is unknown. The Beige mouse also defective in Lyst is a good model of the human disease. Purified lysosomes from Beige and normal black mouse livers were used to carry out a proteomics study. Two-dimensional gel electrophoretic separation of soluble lysosomal proteins of Beige and normal mice revealed no major differences. The cleavable isotope-coded affinity tag (cICAT) technique was used to compare the composition of Beige and normal lysosomal membrane proteins. While the levels of common proteins, that is, Lamp1, Lamp2, and Niemann-Pick type C1, were decreased in Beige mice, there was an increase in the levels of endoplasmic reticulum (ER) resident proteins, for example, cytochrome P450, NADPH-cytochrome P450 oxidoreductase, and flavin-containing monooxygenase. Confocal microscopy confirmed that another ER protein, calnexin, colocalizes with Lamp1 on membranes of giant lysosomes from fibroblasts of Chediak-Higashi syndrome patient. Our results suggest that LYST may play a role in either preventing inappropriate incorporation of proteins into the lysosomal membrane or in membrane recycling/maturation.

Animals↗

PubMed2006

Identification of the gene encoding the enzyme deficient in mucopolysaccharidosis IIIC (Sanfilippo disease type C).

Mucopolysaccharidosis IIIC (MPS IIIC), or Sanfilippo C, represents the only MPS disorder in which the responsible gene has not been identified; however, the gene has been localized to the pericentromeric region of chromosome 8. In an ongoing proteomics study of mouse lysosomal membrane proteins, we identified an unknown protein whose human homolog, TMEM76, was encoded by a gene that maps to 8p11.1. A full-length mouse expressed sequence tag was expressed in human MPS IIIC fibroblasts, and its protein product localized to the lysosome and corrected the enzymatic defect. The mouse sequence was used to identify the full-length human homolog (HGSNAT), which encodes a protein with no homology to other proteins of known function but is highly conserved among plants and bacteria. Mutational analyses of two MPS IIIC cell lines identified a splice-junction mutation that accounted for three mutant alleles, and a single base-pair insertion accounted for the fourth.

3' Untranslated Regions↗

PubMed2006

[Soil microbial ecological process and microbial functional gene diversity].

Soil microbes in terrestrial ecosystem carry out a series of important ecological functions, such as geo-chemical cycling of elements, degradation of pollutants, and buffering to the acute changes of environment, etc. Soil microbial ecological function has a close relation with soil function, and the changes in the structure and composition of soil microbial populations can directly affect the realization of soil function. Through their produced enzymes, soil microbes take part in a series of metabolic activities, and the functional genes of coded enzymes are the functional markers of microbes. In recent ten years, molecular ecology focusing on the functional gene diversity has been developed rapidly, which gives us a new cut-in point to understand soil microbial ecological function from the point of functional gene. This paper reviewed the research advances in the functional gene diversity correlated to soil microbial ecological function, with the perspectives in this field discussed.

Bacteria↗

PubMed2006

[Genetic diversity of arbuscular mycorrhizal fungi associated with four Alnus species in Changbai Mountains: a nested PCR-rFLP analysis].

In this paper, the colonization of arbuscular mycorrhizal fungi (AMF) on the root samples of 4 Alnus species in Changbai Mountains was investigated by using nested PCR-RFLP technique, and the PCR results were tested by restriction endonuclease analysis method. The results revealed that the uncultured AMF had a high genetic diversity, and the colonization had a trend from promiscuity to specialization. The AMF from Alnus mandshuica showed the greatest specialization to the host, and Glomus was the dominant colonizer of A. mandshuica. The AMF from A. sibirica var. hirsuta, A. sibirica, and A. tinctoria showed promiscuity, and host had more significant effects on the colonization of AMF than altitude.

Alnus↗

PubMed2005

Impacts of methamidophos, copper, and their combinations on bacterial community structure and function in black soil.

The potential ecotoxicologial risks of methamidophos, copper, and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rDNA-PCR-DGGE analysis approach, and functional characteristics at community levels by using BIOLOG(GN) system analysis method as well as two conventional methods (DHA and SIR). All results of DGGE banding fingerprint patterns (amplified by bacterial specific 16S rDNA V3 high variable region universal primer) indicated that the species richness of bacterial community in tested soil was significantly decreased to different extents by using different concentrations of single methamidophos, copper, especially some of their combinations had worse effects than their corresponding single factors. In addition, the structures of soil bacterial community had been disturbed under all stresses applied in this study because of the enrichment of some species and the disappearance of other species from the bacterial community. The effects of the single factors with lower concentrations on the community structure were weaker than those with higher concentrations. Moreover, the bacterial community structures under the combined stresses of methamidophos and copper were significantly different from those of control and their corresponding single factors. The change of DHA and carbon source substrate utilizing fingerprint patterns based on BIOLOG(GN) system were two relatively sensitive directors corresponding to the stress presented in this study. Between methamodophos and copper, there happened the significant joint-toxic actions when they were used in combination on DHA and carbon source substrate utilizing fingerprint patterns of soil bacterial communities. The DHA of soil under the combined stresses was lower than that of the control and that under the single factors, and the BIOLOG(GN) substrate utilizing patterns of soil treated by combinations were distinctively differentiated from the control and their corresponding single factors. From all of above, the methamidophos, copper, especially their combinations had the clearly potential ecotoxicological risks to influence the natural soil microbial ecological system by changing the structure, richness, and the functional characteristics of microbial community.

Bacteria↗

PubMed2005

A study of gene expression profiles of cultured embryonic rat neurons induced by phenylalanine.

To have more insight into the mechanism of neuronal injury in phenylketonuria (PKU) patients, gene expression profiles were studied in cell culture of embryonic rat cortical neurons induced by phenylalanine. Randomly chose cortical cultured for 3 days were treated by 0.9-mM phenylalanine for 12 h. Control group of the same batch was treated with the same volume of medium. Total RNA was extracted and hybridized with the Affymetrix gene chip U34 according to the protocol provided by the Affymetrix Company. Real-time PCR was used to further confirm the result. We found that the hybridization signals of 167 genes were increased among the total 1323 probes plotted on the chip. The 167 increased genes could be functionally categorized into signal transduction, neuron related, cytoskeleton, metabolism, ion channels, transcription factors, cytokines, and apoptosis related. Signals of seven probes were decreased, which accounted to 0.5% of the total number. A series of genes that were not reported previously were upregulated by phenylalanine, including Ca2+/calmodulin-dependent protein kinase, Brain type II (CaMK II), ras, P38, L-voltage dependent calcium channel, some genes related to vesicle formation and transmitter release, some glutamate receptor subunits and glutamate transporters. According to the gene expression profiles, it is likely that multiprocesses are involved in the neuronal injury induced by phenylalanine, such as the activation on of the NMDR-Ca2+-CaMK II-Ras-P38 axis, the abnormality in neurotransmitter release. Our study also suggests that the excitatory neurotransmitter glutamate may play a role in the neural pathology of PKU.

Animals↗

PubMed2005

[SO2-caused oxidative stress and modulation of some signal molecules in wheat].

By adding different concentration SO2 to culture boxes, this paper studied the responses of wheat seedling's superoxide anion radical O2*- and antioxidant enzymes to SO2. The results showed that when the concentration of SO2 was 10 and 40 microl x L(-1), the O2*- content and peroxidase (POD) and catalase(CAT) activities of wheat leaf were increased, while the activity of superoxide dismutase(SOD) was reduced. When the SO2 concentration was 50 microl x L(-1), the activities of POD and CAT were decreased, with the top end leaves appeared necrosis, and more fungi multiplied on green leaves. Presoaking wheat seeds with 1 mmol x L(-1) salicylic acid (SA) for 6 h or with 10 mmol x L(-1) H2O2 for 12 h could efficiently alleviate the oxidative stress caused by SO2, with the O2*- content decreased and the activities of test antioxidant enzymes increased. Under SO2 fumigation, ethylene significantly inhibited the activities of test enzymes, and promoted the O2*- production rate. When applying SA and ethylene at the same time, SA could almost completely eliminate the influences of ethylene on O2*- production and test enzyme activities.

Catalase↗

PubMed2005

[Effects of acetochlor and methamidophos on culturable fungal population and community structure in black soil].

By the methods of CFU and rDNA-PCR-DGGE, this paper studied the dynamic changes of culturable fungal populations, community structure, and population richness in black soil under stress of acetochlor and methamidophos. The results showed that the growth of fungi was promoted under lower concentration acetochlor (50 mg x kg(-1)), but long-standing inhibited under its higher concentration (250 mg x kg(-1)). 250 mg kg(-1) methamidophos promoted the growth of culturable fungi intensively during 8-week period, resulting in 10 times increase in CFU of fungi than the control, while low concentration methamidophos (50 mg x kg(-1)) had no evident effect. The richness of culturable fungi in soil treated by medium and high concentration acetochlor was decreased irreversibly. Cluster analysis of fungal rDNA-PCR-DGGE fingerprints profile showed that acetochlor and methamidophos could change the culturable fungal community structure diversely, and the effect of methomidophos was more obvious.

Fungi↗

PubMed2004

[Research advances in soil fungal diversity and molecular ecology].

Fungi are a kind of important soil microorganisms that participate in the decomposition of organic materials and supply nutrients to the plant through symbiosis. But, they can also reduce the output of food due to the existence of pathogenic fungi. Soil fungal diversity plays a fundamentally unique role in maintaining the balance of ecosystem and in supplying large amount of undeveloped resources for the people. In this paper, soil fungal diversity was expatiated from the viewpoints of species diversity, habitant diversity and functional diversity, and furthermore, the research advances in the molecular ecology of soil fungal diversity were reviewed from the aspects of the fungal diversity of farmland, woodland, pasture, extreme environment, and other complex environments. The affecting factors of soil fungal diversity were discussed, and the development trend of the study on soil fungal diversity was also approached.

Basidiomycota↗

PubMed2003

[Introduction and progress of molecular microbial ecology].

Molecular microbial ecology is an interdisciplinary field of molecular biological techniques and microbial ecology, which deals with microbial population, diversity, function, and relationships between microorganisms and biotic and abotic environments in microbial ecosystem. All the progress in molecular microbial ecology, especially in microbial diversity, phylogeny and communities of some microoganisms, indicate the renovation in traditional microbial ecology by the introduction of molecular techniques and strategies. This article reviewed the ideation, development, key domains, main methods and the future hot fields in molecular microbial ecology.

Ecology↗