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Ye Huang

Publications and source records attributed to Ye Huang.

6 recordsLinked to original sources
PubMed2006

Label-free and reagentless aptamer-based sensors for small molecules.

A label free, reagentless aptasensor for adenosine is developed on an ISFET device. The separation of an aptamer/nucleic acid duplex by adenosine leads to the aptamer/adenosine complex that alters the gate potential of the ISFET. The sensitivity limit of the device is 5 x 10-5 M. Also, the immobilization of the aptamer/nucleic acid duplex on an Au-electrode and the separation of the duplex by adenosine mono-phosphate (AMP) enable the electrochemical detection of adenosine by faradaic impedance spectroscopy. The separation of the aptamer/nucleic acid duplex by adenosine and the formation of the aptamer/adenosine complex results in a decrease in the interfacial electron-transfer resistance in the presence of [Fe(CN)6]3-/4- as redox active substrate.

Adenosine Monophosphate↗
PubMed2005

[Acetabular retroversion in hip dysplasia].

OBJECTIVE: To study the occurrence and radiograph features of the acetabular retroversion in hip dysplasia, and to evaluate the effects on the retroversion by the traditional maneuvers in the periacetabular osteotomy. METHODS: Bernese periacetabular osteotomy was performed to 45 continuous dysplastic hips (43 patients) from December 2001 to November 2003. There were 37 female (39 hips) and 6 male (6 hips), average age was 28.9 (range, 15-45). The diagnosis of acetabular retroversion was based on the "cross-over" and "posterior wall" signs on the standard radiographs of the patients pre- or postoperatively. RESULTS: Among total 45 hips, the "cross-over" sign was positive in 8 hips, whereas including the "posterior wall" sign positive in 5 hips. The occurrence of retroversion was 17.8%. And the cross-over points were located within the superior 1/3 of the acetabulums in all cases. After the osteotomy, all the cross-over points moved to the inferior 1/3 of the acetabulums, and the "posterior wall" sign was seen in all 8 cases. CONCLUSIONS: Approximately one sixth of the patients with acetabular dysplasia have retroversion in which the superior 1/3 of the acetabulum faces posterolaterally. The retroversion can be identified with the standard AP pelvic radiographs. With the traditional maneuvers in periacetabular osteotomy, the retroversion will be aggravated in these patients.

Acetabulum↗
PubMed2005

Acetabular medial wall displacement osteotomy in total hip arthroplasty: a technique to optimize the acetabular reconstruction in acetabular dysplasia.

Twenty-six patients (30 hips) who had acetabular dysplasia were operated on by circumferential acetabular medial wall displacement osteotomy to reconstruct the acetabulum during total hip arthroplasty. All patients had cementless acetabular components implanted. The average acetabular component size was 50 mm (range, 44-56 mm). Only 2 hips needed structural bone graft. The mean follow-up period was 22 months (range, 6-32 months). Harris hip score had changed from 47.31 (range, 19-69 points) to 94.69 (range, 85-100 points) postoperatively (P < .01). Using the Ranawat acetabular triangle to determine the optimal hip center of rotation, the postoperative hip biomechanical environment had been improved. Our short-term follow-up suggests this technique is reliable and reproducible and generally avoids the use of bone graft and graft site morbidity. In addition, it allows the use of standard modular cementless components in patients with acetabular dysplasia.

Acetabulum↗
PubMed2003

Effects of manufacturing process variables on in vitro dissolution characteristics of extended-release tablets formulated with hydroxypropyl methylcellulose.

The purpose of this study was to investigate the effect of three process variables: distribution of hydroxypropyl methylcellulose (HPMC) within the tablet matrix, amount of water for granulation, and tablet hardness on drug release from the hydrophilic matrix tablets. Tablets were made both by direct compression as well as wet granulation method. Three formulations were made by wet granulation, all three having the exact same composition but differing in intragranular:intergranular HPMC distribution in the matrix. Further, each formulation was made using two different amounts of water for granulation. All tablets were then compressed at two hardness levels. Dissolution studies were performed on all tablets using USP dissolution apparatus I (basket). The dissolution parameters obtained were statistically analyzed using a multilevel factorial-design approach to study the influence of the various process variables on drug release from the tablets. Results indicated that a change in the manufacturing process could yield significantly dissimilar dissolution profiles for the same formulation, especially at low-hardness level. Overgranulation could lead to tablets showing hardness-dependent drug-release characteristics. Studies showed that intergranular addition of a partial amount of HPMC (i.e., HPMC addition outside of granules) provided a significant advantage in making the formulation more robust over intragranular addition (i.e., that in which the entire amount of HPMC was added to the granules). Dissolution profiles obtained for these tablets were relatively less dependent on tablet hardness irrespective of the amount of water added during granulation.

Chemistry, Pharmaceutical↗
PubMed2002

Influence of hydroxypropyl methylcellulose mixture, apparent viscosity, and tablet hardness on drug release using a 2(3) full factorial design.

This study investigates the effects of three factors: (1) use of a mixture of two different grades of hydroxypropyl methylcellulose (HPMC), (2) apparent viscosity, and (3) tablet hardness on drug release profiles of extended-release matrix tablets. The lot-to-lot apparent viscosity difference of HPMC K15M on in vitro dissolution was also investigated. Four test formulations were made, each containing 10% of a very water-soluble active pharmaceutical ingredient (API), 32% HPMC K15M, or a mixture of HPMC K100LV and HPMC K100M, 56% diluents, and 2% lubricants. Each formulation was made at two hardness levels. A 2(3) full factorial design was used to study various combinations of the three factors using eight experiments conducted in a randomized order. Dissolution studies were performed in USP apparatus I. The values of t50% (time in which 50% drug is released) and tlag (lag time, the time taken by the matrix tablet edges to get hydrated and achieve a state of quasi-equilibrium before erosion and the advance of solvent front through the matrix occur) were calculated from each dissolution profile. The similarity factor (f2) was also calculated for each dissolution profile against the target dissolution profile. A simple Higuchi-type equation was used to analyze the drug release profiles. Statistical analysis using analysis of variance (ANOVA) and similarity factor (f2) values calculated from the data indicated no significant difference among the t50% values and dissolution profiles respectively for all formulations. Within the 3.3-6 kp hardness range investigated, dissolution rates were found to be independent of tablet hardness for all the formulations. Although significantly shorter lag times were observed for the tablets formulated with low- and high-viscosity HPMC mixtures in comparison to those containing a single grade of HPMC, this change had no significant impact on the overall dissolution profiles indicated by the similarity factor f2 values. From this study it can be concluded that lot-to-lot variability in apparent viscosity of HPMC should not be a concern in achieving similar dissolution profiles. Also, results indicated that within the viscosity range studied (12,000-19,500 cps) an HPMC mixture of two viscosity grades can be substituted for another HPMC grade if the apparent viscosity is comparable. Also, the drug release is diffusion-controlled and depends mostly on the viscosity of the gel layer formed.

Analysis of Variance↗