Biomedical subjects

Yan Wang

Publications and source records attributed to Yan Wang.

At least 361 records · Page 20Linked to original sources

PubMed2004

Resistance index in differential diagnosis of liver lesions by color doppler ultrasonography.

AIM: To investigate the specific value of resistance index (RI) in color Doppler ultrasonography in the diagnosis of focal hepatic lesions. METHODS: Eight hundred patients with 893 hepatic solid lesions were studied with color Doppler flow imaging (CDFI) and pulsed Doppler, including 644 malignant cases (596 primary malignant liver tumors, and 48 metastatic liver tumors), 156 benign cases. All were confirmed by operation and pathology. RESULTS: The detection rate of arterial flow in malignant tumors was 92%, and 52% in benign lesions. Doppler spectrum analysis showed that the resistance index in primary malignant tumors was 0.75+/-0.12, 0.73+/-0.09 in metastatic tumors, and was below 0.6 in benign lesions. The difference was significant (P<0.001). This difference was related with its histopathologic structure. CONCLUSION: The arterial flow with RI > or =0.6 identified by CDFI within the liver lesion can be regarded as a criterion of malignant tumors, RI<0.6 can be regarded as benign disorders. RI is useful in differential diagnosis of liver neoplasms.

Adolescent↗

PubMed2004

[Long-term follow-up on disc renarrowing after anterior lumbar interbody fusion with autogenous tricortical iliac crest graft].

OBJECTIVE: To have a retrospective review of the patients undergoing anterior lumbar interbody fusion (ALIF) with clinical and radiological assessment, and observe changing of graft after procedure and assess correlation between graft collapse and recurrence of radiculopathy. METHODS: Sixty-seven consecutive patients undergoing ALIF only at L(4 - 5) with autologous iliac crest graft for intervertebral disc prolapse were followed-up for an average of 14 (2.5 - 32) years. The effect of the fusion was examined by the existence of radiolucent lines and bony continuity on plain radiographs and tomographs, or mobility on flexion-extension radiographs. The disc height was also measured. Lower limb radiculopathy was assessed based on the symptom and examination. Paired samples t-test was used for statistical analysis. RESULTS: Sixty-four patients with successful fusion were analyzed (fusion rate: 96%). All measurements in this study were completed by the same author, and the measurement error of more than 2 mm was statistically significant. According to this, graft collapse occurred in 55 patients (86%) and 9 patients (14%) had no graft collapse. In these 55 cases, the original disc height was (12.1 +/- 2.9) mm, increased immediately after the surgery to (16.2 +/- 1.9) mm, however re-narrowed to (12.9 +/- 2.7) mm at the first observation of solid fusion (a mean of 9 months, ranging from 5 to 14 months), which was not significant different compared to the original. There was no significant change in disc height after solid fusion and the disc space at the final follow-up was (12.6 +/- 2.3) mm. There was no radiculopathy observed in 52 cases (95%) during the follow-up. CONCLUSION: Disc space re-narrowing was observed in most cases after single level ALIF of L(4 - 5), however it was rarely less than the initial and unlikely to result in recurrence of radiculopathy.

Adult↗

PubMed2004

Dipeptidyl aspartyl fluoromethylketones as potent caspase-3 inhibitors: SAR of the P2 amino acid.

This article describes the synthesis and biological evaluation of a series of dipeptidyl aspartyl fluoromethylketones as caspase-3 inhibitors. Structure-activity relationship (SAR) studies showed that for caspase-3 inhibition, Val is the best P(2) amino acid. The SAR studies also showed that the Asp free carboxylic acid in P(1) is important for caspase inhibiting activities, as well as for selectivity over other proteases.

Aspartic Acid↗

PubMed2004

[Characteristics of cardiac arrhythmia in patients with hypertrophic cardiomyopathy].

OBJECTIVE: To investigate the patterns of arrhythmias in patients with hypertrophic cardiomyopathy (HCM) and its relation with the pathology of heart. METHODS: The clinical data, electrical cardiogram (ECG), Holter ECG recordings, and echocardiograms of 85 patients with HCM were collected and analyzed. RESULTS: Seventy four (87%) of the 85 patients with HCM had various forms of arrhythmia, including tachycardia in 30 patients with a prevalence of 35.3%, and bradycardia in 21 patients with a prevalence of 24.7%. The incidence rates of intraventricular conduction block and tachycardiac arrhythmia of the 24 HCM patients with syncope history were 45.8% and 50.0% respectively, both significantly higher than those of the 61 HCM patients without syncope history (21.3% and 26.2% respectively, both P > 0.05). The incidence rate of bradycardiac arrhythmia of the 24 HCM patients with syncope history was 50.0%, significantly higher than that of the 61 patients without syncope history (14.8%, P < 0.001). Arrhythmia, especially bradycardia, was more frequent in the patients with hypertrophy in mid-low part of interventricular septum and cardiac apex. CONCLUSION: Most patients with HCM have various cardiac arrhythmias, and occurrence of syncope and cardiac sudden death in the patients may be caused not only by tachycardia but also by bradycardia. Bradycardia is more frequent in the patients with hypertrophy in mid-low part of interventricular and cardiac apex.

Adolescent↗

PubMed2004

[Clinical observation and following up of two administration methods of arsenic trioxide in treatment of acute promyelocytic leukemia].

OBJECTIVE: To assess the effectiveness and security of two arsenic trioxide (As(2)O(3)) administration methods in treatment of acute promyelocytic leukemia (APL). METHODS: Forty-eight APL cases were treated with As(2)O(3) with the total daily dosage of 0.16 mg/kg that was divided into two equal doses diluted in 250 ml of 5% glucose given twice in the morning and evening respectively by intravenous infusion' at a speed of 8 drops/min with an interval of 2-3 hours. Forty-eight sex- and age-matched APL cases were treated with As(2)O(3) with the same total daily dosage of 0.16 mg/kg given according to the routine method: infused intravenously once a day with a duration of at most 2 hours. Serum was collected at different time points to examine the arsenic concentration. The remission rate and side effects were observed. RESULTS: The remission rate was 93.8% in the patients treated by the new method, and was 83.3% in the patients treated by the routine method 28 days after the treatment. The lasting duration of effective arsenic level was at least 18.4 +/- 3.3 hours in the new method group, and was 9.4 +/- 1.6 hours in the routine method group. The average time from the initiation of treatment to complete remission (CR) in the new method group was 26.4 +/- 2.4 days, and was 35.7 +/- 4.8 days in the routine method group. No late liver functional lesion and bone marrow depression was found in the two groups during the 6 months followed up. CONCLUSION: The 'multi-times and slowing intravenous infusion' method relieves the side effects of As(2)O(3) treatment, increases the CR rate in treatment of APL.

Adolescent↗

PubMed2004

[Relationship between the Demodex and bacteria infection in human rosacea].

OBJECTIVE: To understand the relationship between Demodex and bacteria infection in rosacea (brandy nose), and to find effective means for the treatment. METHODS: Cellophane tape was used to detect Demodex on the nasolabial grooves and the face; sebum and tissue on face was scraped and cultured to examine bacteria under microscope. The hospital-made anti-rosacea lotion was used on the affected part two times a day for 7 days. RESULTS: It was found that 193 (74.2%) of 260 cases with rosacea were infected by Demodex and 209 (80.4%) of the patients were infected by bacteria. The overall effective rate of the treatment for rosacea was 73.5%. CONCLUSION: Bacteria infection in rosacea is an important factor inducing rosacea. The curative effect of the anti-rosacea lotion is good.

Adolescent↗

PubMed2004

[Experimental study of bone morphogenetic protein-2 in noncemented fixation of prosthesis].

OBJECTIVE: To study on the method of combining rhBMP(2) with porous-coated implants, and compared the histological and biomechanical results of 4 types of implants by being inserted into the femur of canine. METHODS: 4 types of implants which are porous-coated implants (PCA), PCA implants combined with BMP, PCA implants coated with hydroxyapatite and HA coated cylindrical implants had been inserted into the femur of 16 canines. After 4, 8, 12 and 24 weeks the femur of the canines with the implants were retrieved. Bone ingrowth and shear strength of the interface was studied and analysed by the means of X-ray, soft X-ray, fluorescence tag, non-decalcification bone ground section, computer-aided image analysis procedure and biomechanical test. RESULTS: X-ray, soft X-ray, fluorescence tag, non-decalcification bone ground section and computer-aided image analysis procedure was used in histological study, and it showed that bony ingrowth into interface more than the other groups, even the maturation of newly formed bone. Non-decalcification bone ground section observation and computer aided image analysis showed the results: the new bone formation ratio of BMP group was 26.58% +/- 4.56% at 4 weeks post-implantation, which was much higher than the other groups, and there was significant difference between BMP group and each of the other group statistically (P < 0.05). Results of biomechanical study using push-out test showed that shear strength of each group appeared to rise with time. Shear strength of BMP group reached a high level at 4 weeks which was 18.94 +/- 5.11Mpa and almost twice of the other group, and there was also statistical difference between BMP group and each of the other group (P < 0.05). And the new bone formation ratio and shear strength of BMP group at 8, 12, 24 weeks post-implantation was still higher than the other group, but there was no statistically difference. CONCLUSIONS: Porous-coated implants combined with rhBMP can enhance bone ingrowth at bone-implant interface especially at the early period post-implantation. Porous-coated implants combined with rhBMP(2) can not only shorten the time of new bone formation and bone ingrowth but also enhance shear strength of bone-implant interface.

Animal Experimentation↗

PubMed2004

A novel strategy to engineer DNA polymerases for enhanced processivity and improved performance in vitro.

Mechanisms that allow replicative DNA polymerases to attain high processivity are often specific to a given polymerase and cannot be generalized to others. Here we report a protein engineering-based approach to significantly improve the processivity of DNA polymerases by covalently linking the polymerase domain to a sequence non-specific dsDNA binding protein. Using Sso7d from Sulfolobus solfataricus as the DNA binding protein, we demonstrate that the processivity of both family A and family B polymerases can be significantly enhanced. By introducing point mutations in Sso7d, we show that the dsDNA binding property of Sso7d is essential for the enhancement. We present evidence supporting two novel conclusions. First, the fusion of a heterologous dsDNA binding protein to a polymerase can increase processivity without compromising catalytic activity and enzyme stability. Second, polymerase processivity is limiting for the efficiency of PCR, such that the fusion enzymes exhibit profound advantages over unmodified enzymes in PCR applications. This technology has the potential to broadly improve the performance of nucleic acid modifying enzymes.

Amino Acid Sequence↗

PubMed2004

Discovery, characterization and SAR of gambogic acid as a potent apoptosis inducer by a HTS assay.

Gambogic acid (2), a natural product isolated from the resin of Garcinia hurburyi tree, was discovered to be a potent apoptosis inducer using our cell- and caspase-based high-throughput screening assays. Gambogic acid was found to have an EC(50) of 0.78 microM in the caspase activation assay in T47D breast cancer cells. The apoptosis-inducing activity of gambogic acid was further characterized by a nuclear fragmentation assay and flow cytometry analysis in human breast tumor cells T47D. Gambogic acid was found to induce apoptosis independent of cell cycle, which is different from paclitaxel that arrests cells in the G2/M phase. To understand the structure-activity relationship (SAR) of gambogic acid, derivatives of 2 with modifications to different function groups were prepared. SAR studies of gambogic acid, as measured by the caspase activation assay, showed that the 9,10 carbon-carbon double bond of the alpha,beta-unsaturated ketone is important for biological activity, while the 6-hydroxy and 30-carboxy group can tolerate a variety of modifications. The importance of the 9,10 carbon-carbon double bond was confirmed by the traditional growth inhibition assay. The high potency of 2 as an inducer of apoptosis, its novel mechanism of action, easy isolation and abundant supply, as well as the fact that it is amenable to chemical modification, makes gambogic acid an attractive molecule for the development of anticancer agents.

Antineoplastic Agents↗

PubMed2004

Solid-phase microextraction combined with surface-enhanced laser desorption/ionization introduction for ion mobility spectrometry and mass spectrometry using polypyrrole coatings.

The successful application of polypyrrole (PPY) solid-phase microextraction (SPME) coatings as both an extraction phase and a surface to enhance laser desorption/ionization (SELDI) of analytes is reported. This SPME/SELDI fiber integrates sample preparation and sample introduction on the tip of a coated optical fiber, as well as acting as the transmission medium for the UV laser light. Using ion mobility spectrometry (IMS) detection, the signal intensity was examined as a function of extraction surface area and concentration of analyte. The linear relationship between concentration and signal intensity shows potential applicability of this detection method for quantitative analysis. Extraction time profiles for the fiber, using tetraoctylammonium bromide as test analyte, illustrated that equilibrium can be reached in less than one minute. To investigate the performance of the PPY coating, the laser desorption profile was studied. The fiber was also tested using a quadrupole time-of-flight (Q-TOF) mass spectrometer with leucine enkephalin as test analyte. Since no matrix was used, mass spectra free from matrix background were obtained. This novel SPME/SELDI fiber is easy to manufacture, and is suitable for studying low-mass analytes because of the intrinsic low background. These findings suggest that other types of conductive polymers could also be used as an extraction phase and surface to enhance laser desorption/ionization in mass spectrometry.

Journal Article↗

PubMed2004

Role of VLDL receptor in the process of foam cell formation.

The role of very low density lipoprotein receptor (LVLDR) in the process of foam cell formation was investigated. After the primary cultured mouse peritoneal macrophages were incubated with VLDL, beta-VLDL or low density lipoprotein (LDL), respectively for 24 h and 48 h, foam cells formation was identified by oil red O staining and cellular contents of triglyceride (TG) and total cholesterol (TC) were determined. The mRNA levels of LDLR, LDLR related protein (ILRP) and VLDLR were detected by semi-quantitative RT-PCR. The results demonstrated that VLDL, beta-VLDL and LDL could increase the contents of TG and TC in macrophages. Cells treated with VLDL or beta-VLDL showed markedly increased expression of VLDLR and decreased expression of LDLR, whereas LRP was up-regulated slightly. For identifying the effect of VLDL receptor on cellular lipid accumulation, ldl-A7-VR cells, which expresses VLDLR and trace amount of LRP without functional LDLR, was used to incubate with lipoproteins for further examination. The results elucidated that the uptake of triglyceride-rich lipoprotein mediated by VLDLR plays an important role in accumulation of lipid and the formation of foam cells.

Animals↗

PubMed2004

Beta-VLDL induced VLDL-R's up-regulation via PKC-ERK1/2 signal pathway.

To explore the intracellular signal pathways for beta-VLDL induced very low density lipoprotein receptor (VLDL-R) transcription up-regulation and their effects on lipid accumulation in macrophages, Western Blot was used to examine phosphorylated ERK1/2 protein and regulated effects by different singal kinase inhibitants. It was found that beta-VLDL induced an increase in ERK1/2 activity in a protein kinase C (PKC)-dependent manner in murine RAW264.7 macrophages. By using different protein kinases inhibitors or activators, it was observed that the effect of beta-VLDL induced VLDL receptor transcription, which was monitored by RT-PCR analysis of VLDL receptor mRNA, was not affected by the inhibitor of p38 kinase and cAMP analog, but extremely abolished by pretreating cells with PD98059, an inhibitor of ERK and GF 109203X, an inhibitor of PKC. These results demonstrated that the PKC-ERK1/2 cascade is the essential signaling pathway by which beta-VLDL activated VLDL-R mRNA expression. Inhibition of the ERK1/2 signaling cascade resulted in suppression of the cellular lipid accumulation induced by beta-VLDL in macrophages.

Cells, Cultured↗

PubMed2004

Cloning and characterization of antikeratin human antibodies using a semisynthetic phage antibody library.

Antikeratin autoantibodies (AK auto Abs) are very important elements of the human immune system. To improve the outcome of studies on AK auto Abs, it is necessary to generate antikeratin human monoclonal antibodies. The purpose of present study was to isolate antikeratin human monoclonal antibodies by panning a phage antibody library. A semisynthetic phage antibody library with capacity of 4.0x10(8) members was previously constructed. Panning of the library was performed against human epidermal keratin extracted from psoriatic scales. At the last round of the panning, individual colonies were grown in culture for expression of phage antibodies. Their binding activities and specificities to keratin were determined by ELISA, and positive clones were analyzed by DNA fingerprinting. The selected clones were induced with IPTG to express soluble Fab fragments, which were further characterized by ELISA, immunohistochemistry and Western blotting. Finally, DNA sequencing of the variable regions was performed. A human antibody clone which was able to express soluble Fab fragments and recognize Mr 46,000 keratin (K17) was isolated. DNA sequencing demonstrated that the VH and VL of the antibody came from the human VH1 and Vkappa2 families, respectively. We conclude that phage antibody library technology is a powerful way to generate human monoclonal antibodies. The antikeratin antibody we isolated in the present study would be useful in the research on AK auto Abs.

Amino Acid Sequence↗

PubMed2004

Microarray analysis of proliferative and hypertrophic growth plate zones identifies differentiation markers and signal pathways.

Longitudinal bone growth results from coordination of proliferation and hypertrophy of chondrocytes, calcification of the matrix, vascular invasion, and completion of endochondral bone formation in the growth plate. Although proliferative and hypertrophic chondrocytes are well characterized histomorphologically, the understanding of factors governing this transition is not fully explained. Our hypothesis was that significant differential gene expression exists between proliferative and hypertrophic chondrocytes that may provide clues to the regulation of this transition at the transcriptional level. Normal Sprague-Dawley rat growth plate chondrocytes from the proliferative zone (PZ) and hypertrophic zone (HZ) were isolated by laser capture microdissection and then subjected to microarray analysis. Confirmation of the differential expression of selected genes was done by in situ hybridization and quantitative reverse transcription (RT) polymerase chain reaction (PCR). A total of 40 transcripts showed at least twofold greater expression in the PZ compared to HZ at both 6 and 7 weeks of age, while 52 transcripts showed twofold greater expression in the HZ compared to PZ at these time points. Many of the differentially expressed genes in each zone had very high levels of expression and thus were classified as "enriched transcripts" for that zone. The PZ-enriched transcripts included fibromodulin, proline arginine-rich end leucine-rich repeat protein, lactate dehydrogenase, and enolase 1 alpha. In contrast, HZ-enriched transcripts included collagen I, protein kinase (lysine deficient 4), proteasome (prosome, macropain) activator subunit 4, prostaglandin I2 synthase, and integrin-binding sialoprotein, matrix metalloproteinase 13 (MMP13), and collagen X. Other genes were highly expressed in cells from both zones, including collagen II, aggrecan, cartilage oligomeric protein, cartilage link protein, laminin receptor, and eukaryotic translocation elongation factor. Functional classification of the PZ-enriched transcripts showed an increased percentage of genes expressed in nuclear cell cycle and transcription functions. In contrast, the HZ-enriched transcripts were more involved in extracellular structure and membrane receptor and transporter functions. Pathway analysis indicated that transforming growth factor beta and parathyroid hormone-related protein (PTHrP) pathways were important in both zones, and bone morphogenic protein pathway played a role in the HZ. It is likely that these differentially expressed genes are involved in regulation of the transition from proliferation to differentiation functions in the growth plate.

Animals↗

PubMed2004

Immunohistochemical and ultrastructural markers suggest different origins for cuboidal and polygonal cells in pulmonary sclerosing hemangioma.

We report the morphological characteristics of 30 cases of sclerosing hemangioma (SH) of the lung and explore the histological origin of the major cells in these tumors. In addition to routine light and electron microscopy, immunohistochemistry was performed by using 12 monoclonal primary and 5 polyclonal primary antibodies. These included surfactant protein B (SP-B), thyroid transcription factor-1 (TTF-1), mast cell trypsin, CD68, epithelial antigen markers (high molecular weight cytokeratin, low molecular weight cytokeratin [CK-L], epithelial membrane antigen [EMA], cancer embryonic antigen), mesothelial antigen, neuroendocrine markers (neuron-specific enolase [NSE], chromogranin A, synaptophysin, calcitonin, adrenocorticotropic hormone, human growth hormone [hHG]), vimentin, and CD34. Surface cuboidal cells have short microvilli and have lamellar bodies in their cytoplasm. They can sometimes merge into multinuclear giant cells. Immunohistochemical results showed that these cells are strongly positive for SP-B, TTF-1, CK-L, EMA, and cancer embryonic antigen, whereas polygonal cells, previously also described as round or pale cells, were strongly positive for vimentin and TTF-1, and positive or weakly positive for 2 to 3 kinds of neuroendocrine markers. Sparse neuroendocrine granules and abundant microfilaments were observed in their cytoplasm. Some cell clusters in the solid regions were positive for SP-B and EMA. Mast cells existed sparsely in almost every field. Both cuboidal and polygonal cells were negative to CD34 and mesothelial antigen staining. We conclude that cuboidal cells of SH originate from reactive proliferating type II pneumocytes, which can fuse into multinuclear giant cells. Polygonal cells, as true tumor cells, likely originate from multipotential primitive respiratory epithelium and possess the capability for multipotential differentiation. The antibodies of SP-B, TTF-1, vimentin, and CK-L are very helpful to diagnosis and differential diagnosis of SH.

Adult↗

PubMed2004

Ac-SAA-1, an immunodominant 16 kDa surface-associated antigen of infective larvae and adults of Ancylostoma caninum.

A cDNA encoding a surface-associated antigen was cloned from an Ancylostoma caninum infective larvae (L(3)) cDNA library by immunoscreening with pooled human immune sera. The sera were obtained from individuals living in an Ancylostoma duodenale hookworm-endemic region of China, who had light intensity infections and high antibody titers against A. caninum L(3). Ancylostoma caninum surface-associated antigen-1 is encoded by an 843 bp mRNA with a predicted open reading frame of 162 amino acids. Recombinant Ancylostoma caninum surface-associated antigen-1 was expressed in Escherichia coli and used to prepare a specific antiserum. A Western blot with anti-Ancylostoma caninum surface-associated antigen-1 specific antiserum showed that native Ancylostoma caninum surface-associated antigen-1 protein is expressed by both L(3) and adult hookworms; RT-PCR confirmed that the mRNA is transcribed in both stages. In adult hookworms, the protein localised to the basal layer of the cuticle and hypodermis of adult worms. Serological analysis determined that recombinant Ancylostoma caninum surface-associated antigen-1 protein is recognised by 61% of human sera from a Necator americanus hookworm endemic area in China, indicating the antigen is immunodominant. Anti-Ancylostoma caninum surface-associated antigen-1 antiserum partially inhibited (46.7%) invasion of hookworm L(3) into dog skin in vitro. Together these results suggest that Ancylostoma caninum surface-associated antigen-1 offers promise as a protective vaccine antigen.

Amino Acid Sequence↗

PubMed2004

Effect of pramlintide on symptom, catecholamine, and glucagon responses to hypoglycemia in healthy subjects.

Pramlintide is an analog of the human glucoregulatory hormone amylin. Previous studies have shown no clear evidence that pramlintide modifies the response to insulin-induced hypoglycemia; however, a detailed assessment of responses at hypoglycemic thresholds has not been conducted. To further test the effect of pramlintide on symptom, catecholamine, and glucagon responses, a 3-step hypoglycemic clamp was investigated in healthy volunteers. In a randomized, double-blind, placebo-controlled, crossover study, 18 healthy subjects without diabetes received subcutaneous premeal injections of either placebo or 60 microg pramlintide 3 times daily for 5 consecutive days. On day 6, subjects received study drug with breakfast and, after a 7-hour fast, were connected to a Biostator for a 3-step, 3-hour clamp experiment (insulin infusion rate: 1.0 mU/kg/min; blood glucose targets: 70, 55, and 45 mg/dL). An intravenous (IV) infusion of pramlintide (16 microg/h) or placebo was initiated at t = 60 minutes. At the end of each 60-minute clamp step, autonomic (sweating, palpitations, hunger, etc) and neuroglycopenic (confusion, headache, odd behavior, etc) symptoms were assessed using a validated visual analog scale questionnaire. Blood samples were collected at 30-minute intervals for measurement of plasma glucose, insulin, pramlintide, catecholamine, and glucagon concentrations. Intraindividual and group mean responses showed that autonomic symptoms and plasma catecholamine and glucagon concentrations increased progressively during the clamp, with no discernible differences between pramlintide and placebo treatments. Group means for catecholamines at 60 minutes were: epinephrine 233 +/- 42, 892 +/- 85, 2,340 +/- 302 and 202 +/- 25, 774 +/- 114, 2,751 +/- 404 pg/mL and norepinephrine 1,138 +/- 86, 1,236 +/- 77, 1,721 +/- 158 and 1,278 +/- 108, 1,259 +/- 109, 1,580 +/-136 pg/mL (+/- SEM) for placebo- and pramlintide-treated groups at 70, 55, and 45 mg/dL glucose, respectively. Group means for glucagon were 72 +/- 6.3, 98 +/- 11.1, 130 +/- 14.7 and 63 +/- 3.6, 92 +/- 9.4, 120 +/- 16.0 pmol/L (+/- SEM) for placebo- and pramlintide-treated groups at 70, 55, and 45 mg/dL glucose, respectively. These results showed that pramlintide did not impair the symptom, catecholamine, and glucagon responses to insulin-induced hypoglycemia in healthy subjects.

Adolescent↗

PubMed2004

Synthesis of a novel host molecule of cross-linking-polymeric-beta-cyclodextrin-o-vanillin furfuralhydrazone and spectrofluorimetric analysis of its identifying cadmium.

A novel host inclusion complex of cross-linking-polymeric-beta-cyclodextrin-o-vanillin furfuralhydrazone (beta-CDP-OVFH) was synthesized and characterized with IR and 1H NMR spectra to confirm its structure. The coordination reaction of the host reagent with Cd(2+) was studied and the optimum reacting conditions were observed carefully. A highly selective and sensitive spectrofluorimetric determination of trace amount of cadmium was proposed based on the reaction of Cd(2+) with beta-CDP-OVFH in ammonia water-ammonium acetate buffer medium of pH = 11.0. The molar ratio of beta-CDP-OVFH to Cd(2+) was 1:1. The maximum excitation and emission wavelengths were 393 and 494 nm, respectively. The linear range of this method was from 3.0 to 500 microg l(-1) with a detection limit of 0.80 microg l(-1). The effect of interferences in the determination of cadmium was investigated and the results showed that the host reagent had quite high capacity of identifying Cd(2+). The proposed method was successfully applied to the determination of trace amount of Cd(2+) in mussel and tea samples.

Benzaldehydes↗