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Biomedical subjects

F S Huang

Publications and source records attributed to F S Huang.

At least 19 recordsLinked to original sources

Serum from mice after small bowel resection enhances intestinal epithelial cell growth.

BACKGROUND/PURPOSE: The adaptive response of the intestine to massive small bowel resection (SBR) is remarkably complex. An in vitro model of adaptation may facilitate the elucidation of signaling pathways involved in this process. In an effort to establish such a model, the effects of serum from resected mice on cultured intestinal epithelial cells were studied. METHODS: Serum was collected and pooled from male ICR mice 3 days after either 50% SBR or sham operation. Rat intestinal epithelial cells (RIEC-6) were plated at equal density and grown in the presence of 1% fetal bovine serum (FBS), 10% FBS, 1% FBS plus 9% sham serum, or 1% FBS plus 9% SBR serum. Cell number, proliferation, and caspase-3 activity were determined. RESULTS: RIEC-6 cell growth was reduced significantly in 1% FBS or sham serum. SBR serum markedly accelerated cell growth and proliferation when compared with all other groups and significantly suppressed caspase-3 activity. CONCLUSIONS: Massive intestinal resection in mice results in a serum factor that induces intestinal cell growth in vitro. This in vitro model of trophic signaling will permit further detailed investigations into the mechanisms of intestinal adaptation.

Adaptation, Biological↗

cDNA microarray analysis of adapting bowel after intestinal resection.

BACKGROUND/PURPOSE: Studies of the genetic regulation of various physiologic processes have been hampered by methodologies that are limited to the analysis of individual genes. The advent of cDNA microarray technology has permitted the simultaneous screening of numerous genes for alterations in expression. In this study, cDNA microarrays were used to evaluate gene expression changes during the intestinal adaptive response to massive small bowel resection (SBR). METHODS: Male ICR mice (n = 20) underwent either a 50% SBR or sham operation and then were given either orogastric epidermal growth factor (EGF, 50 microg/kg/d) or saline. After 3 days, cDNA microarray analysis was performed on mRNA extracted from the remnant ileum. RESULTS: From over 8,700 different genes, the array identified 27 genes that were altered 2-fold or greater after SBR. Small proline-rich protein 2 (sprr2), the gene with the greatest expression change (4.9-fold), was further upregulated by EGF. This gene has never been characterized in the intestine or described in intestinal adaptation. CONCLUSIONS: cDNA microarray analysis showed enhanced expression of sprr2, a gene not previously known to be involved in the physiology of adaptation after SBR. This technology provides a more rapid and efficient means of dissecting the complex genetic regulation of gut adaptation.

Adaptation, Biological↗

Intestinal adaptation: structure, function, and regulation.

After massive small bowel resection (SBR), the remnant intestine undergoes an adaptive process characterized by increases in wet weight, protein and DNA content, villus height and crypt depth, and absorptive surface area. These changes are the result of a proliferative stimulus that increases crypt cell mitosis and augments cellular progression along the villus axis. Functionally, there is upregulation of the Na(+)/glucose cotransporter, Na(+)/H(+) exchanger, and other enzymes involved in intestinal digestion and absorption. These physiologic events are a compensatory response to the sudden loss of digestive and absorptive capacity by the remnant intestine. A major consequence of inadequate intestinal adaptation is lifelong dependence on parenteral nutrition, which results ultimately in cholestatic liver dysfunction. Furthermore, adaptation may be associated with changes in intestinal permeability and an increased risk of bacterial translocation and sepsis. Several mediators thought to be integral to the postresection adaptive response have been proposed, including luminal nutrients, gastrointestinal secretions, and humoral factors. A thorough understanding of intestinal adaptation will be essential in the rational development of new and innovative therapies that amplify this complex but important process.

Animals↗

Renal cell carcinoma as a secondary malignancy after treatment of acute promyelocytic leukemia.

Numerous children have been treated successfully for cancer and are surviving into adulthood. As this population has aged, an increasing number of secondary malignancies has emerged. Renal cell carcinoma (RCC) is a rare tumor in childhood and has not been documented previously to occur after treatment of acute promyelocytic leukemia (APL). This report describes the clinical course of APL treated in a child in whom RCC subsequently developed during adolescence approximately 5 years after therapy.

Antineoplastic Combined Chemotherapy Protocols↗

[Cloning and characterization of three novel genes encoding transmembrane proteins of Schistosoma japonicum].

OBJECTIVE: To clone and analyze novel antigen molecules of Schistosoma japonicum (Sj), and to provide effective vaccine candidate antigens against schistosomiasis japonica. METHODS: Sj adult cDNA library was screened using sera of mice infected with Trichinella spiralis (Ts) and the inserts of positive clones were specifically amplified by PCR. The positive clones were sequenced and the sequence data were analyzed using Nucleotide BLAST software of NCBI and Expert Protein Analysis System of Swiss Institute of Bioinformatics. RESULTS: Nine positive clones were obtained after three rounds of immunoscreening. The size of these inserts ranged from 0.6 kb to 2.1 kb. Among five novel genes, Sj-Ts1, Sj-Ts3 and Sj-Ts5 (GenBank accession number: AY005816, AF299080 and AY024352, respectively) encode trans-membrane proteins with 83, 83 and 233 amino acids, respectively. Sj-Ts1 protein predicted contains one possible trans-membrance helix, one N-myristoylation site, two phosphorylation sites for protein kinase C and one for tyrosine kinase, Sj-Ts3 protein contains two possible transmembrance helices and one casein kinase II phosphorylation site, whereas Sj-Ts5 protein has five possible transmembrance helices, one N-glycosylation site, one N-myristoylation site, two phosphorylation sites for cAMP- and cGMP-dependent protein kinase and four for protein kinase C and one for casein kinase II. CONCLUSION: Three novel genes encoding three transmembrane proteins might be developed as new vaccine candidates against Sj infection.

Amino Acid Sequence↗

A DPDPE-induced enhancement of inward rectifier potassium current via opioid receptor in neuroblastomaxglioma NG108-15 cells.

The effect of a delta-selective opioid agonist, DPDPE([D-Pen(2, 5)]-enkephalin), on the inward rectifier potassium current (I(KIR)) of NG108-15 cell was studied by whole cell voltage-clamp technique. It was found that microM DPDPE increased the amplitude and delayed the activation and inactivation of I(KIR) rapidly and reversibly. These effects could be reversed by naloxone, but were still obtained in pertussis toxin (PTX) preincubated cells or when using GDP-betas (guanosine 5'-o-[2-thio] diphoaphate) containing electrodes to block the G-protein coupled events. The above results suggest that DPDPE-induced change of I(KIR) is mediated by delta-opioid receptor but does not involve G-proteins.

Animals↗

Irreducible posterolateral dislocation of the knee.

Traumatic knee dislocations are relatively rare, often associated with neurovascular injury, and almost always amenable to closed reduction. However, over the years, several authors have recognized that the rare knee dislocation not reducible by closed manipulation usually involves posterolateral dislocation of the tibia and button-holing of the medial femoral condyle through the medial retinaculum. These cases present with a dimple sign, a characteristic invagination of tissues at the medial joint line. Open reduction entails extraction of the soft-tissue collar that becomes incarcerated in the trochlea and intercondylar notch. We present an interesting case of irreducible posterolateral knee dislocation and review many of the salient points associated with this entity. Additionally, we include intraoperative video footage available on the Journal Web site to promote a better appreciation of the dramatic visual presentation and physical examination of this unusual injury.

Follow-Up Studies↗

[Relationship between hemolymph phenol oxidase and melanization of oocysts of Plasmodium yoelii in Anopheles stephensi].

OBJECTIVE: To explore the relationship between the hemolymph phenol oxidase and melanization of oocysts. METHODS: Anopheles stephensi-Plasmodium yoelii system was used to determine the activity of monophenol oxidase (MPO) and o-diphenol oxidase (o-DPO) in the hemolymph collected from 4 groups of mosquitoes by polyacrylamide gel electrophoresis (PAGE) followed by density scanning. The 4 groups of mosquitoes were: non-blood-fed (N), normal-blood-fed (B), infected-blood-fed (I) and nitroquine-administrated (D), respectively. RESULTS: No significant difference was found in the activities of MPO and o-DPO between groups N and B. The activities of MPO and o-DPO were not obviously modified in group I, but were significantly increased on day 10 and decreased on day 15 after blood feeding in the group D as compared with those in the groups N and B. CONCLUSION: The alteration in the mosquito hemolymph PO activity coincided at each time point with the melanization of Plasmodium yoelii oocysts.

Animals↗

[Analysis of Pagumogonimus skrjabini antigen and its application in serodiagnosis].

OBJECTIVE: To analyse the soluble antigens of different developmental stages of Pagumogonimus skrjabini and develop a specific and sensitive serodiagnostic method for pagumogonimiasis. METHODS: The soluble antigens of P. skrjabini of various stages were separated by SDS-PAGE. The specific antigen of the adult fluke was recognized immunologically by immunoblot assay. The protein bands between 10-30 kDa purified by SDS-PAGE and electrophoretic elution were used in dot-ELISA. RESULTS: Using dot-ELISA, the soluble antigens of adult were recognized by sera infected with P. skrjabini. More reactive bands appeared at 10-30 kDa, but major protein bands were at 22, 24 and 26 kDa. However, using sera from patients infected with other trematodes including schistosome and Clonorchis, cross-reaction bands appeared within 60 to 90 kDa. When compared with ELISA of crude adult antigens for detecting 28 suspected patients, there was no significant difference between the two methods. The sera of 38 patients with other diseases were also detected by the two tests. No cross-reaction occurred with the purified adult antigen dot-ELISA while 13.2% (5/38) of the sera cross-reacted in ELISA of crude adult antigens. CONCLUSION: Dot-ELISA using 10-30 kDa antigen might be a specific and sensitive serodiagnostic method for diagnoing pagumogonimiasis.

Adolescent↗

[The inhibitory effects of artemisinin-derivatives on Na+ and K+ channels in comparison with those of procaine].

Some derivatives of artemisinin have been shown to have local anesthesia action. By using patch-clamp whole cell recording configuration, the effects of five artemisinin-derivatives on the voltage-gated INa and IK have been studied on differentiated NG108-15 cells with reference to procaine. The results showed that all the five artemisinin-derivatives clearly inhibited the voltage-gated sodium current (INa) of the cells in a dose-dependent manner and the effect was partially reversibly. Among the five artemisinin-derivatives, SM541 has been shown to be most potent, approaching that of procaine. However, 300 mumol/L procaine showed only a slight inhibition of IK, whereas all the five derivatives at the same concentration not only decreased IK clearly, but also accelerated its inactivation. Except for SM541, the inhibitory effects on IK decreased rapidly with perfusion of the rest 4 derivatives.

Anesthetics, Local↗

[Effect of alpha-difluoromethylornithine on sporogony of Plasmodium yoelii].

The effect of alpha-difluoromethylornithine (DFMO) on the sporogony of P yoelii was studied by electron microscopy. DFMO sugar solution was fed to female mosquitoes. Scanning electron microscopy (SEM) revealed that the oocysts were smaller and the surface of oocysts was uneven as compared with control. Transmission electron microscopy (TEM) showed that cytoplasm of the affected oocysts contained vacuoles and the multilamellate structures increased. The number of matrix cavitations and deformations of mitochondria increased. Nuclear membrane was damaged. The number of autophagocytic vacuoles increased. The membrane system was markedly affected.

Animals↗

[Effect of Poly I:C on the sporozoite invasion and the development of exoerythrocytic forms of Plasmodium yoelii yoelii in rats].

When Wistar rats were given intravenously with Poly I:C 5 mg/kg 18 h before sporozoite inoculation, the density of exoerythrocytic forms (EEF) in the rat liver 42 h after inoculation was markedly decreased, the sporozoite viability being only 5-12% of that of the controls. However, the size and maturation rate of EEF were all normal. When Poly I:C was given 2 h after sporozoite inoculation, the sporozoite viability and the size and the maturation rate of EEF were similar to those of the controls. When the sporozoites were inoculated with rat serum containing interferon for 40 min before inoculation, no detrimental effect on the sporozoite invasion and the development of EEF could be found. These findings suggested that the target of antimalarial action of interferon might not be the EEF itself. It is possible that interferon could minimize the sporozoite number by enhancing the phagocytosis and the biocidal activity of macrophages, especially the Kupffer cells.

Animals↗

[Analysis of amino acids in hemolymph and acid hydrolysates of midguts of Anopheles dirus infected with Plasmodium cynomolgi].

Quantitative determinations of free amino acids in hemolymph and acid hydrolysates of midguts of female Anopheles dirus infected with Plasmodium cynomolgi bastianellii were carried out and the results were compared with those of noninfected mosquitoes. On day 10 after infected blood meal, the contents of methionine, isoleucine, leucine, ornithine, lysine in the hemolymph of infected mosquitoes markedly decreased as compared with those in the controls. However, the quantitative analysis of the amino acids of the acid hydrolysates of the midguts from infected mosquitoes on day 9 after an infected blood meal showed that the content of their total amino acids was 70% more than that in the controls, with special reference to aspartic acid, glutamic acid, valine, methionine, isoleucine, leucine, phenylalanine, tryptophan.

Amino Acids↗