• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.469-477
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• 2018

We describe surgical sutures enabled with the local, sustained delivery of a TGF-${\beta}$ inhibitory drug, tranilast. To fabricate drug-delivery sutures, we separately prepared a tranilast-loaded strand using poly (lactic-co-glycolic acid), which was then physically braided with a surgical suture already in clinical use. By this method, the drug-delivery sutures maintained the mechanical strength and allowed the modulation of drug release profiles by simply altering the tranilast-loaded strand. The drug-delivery sutures herein released tranilast for up to 14 days. When applied to animal models, scarring was indeed reduced with diminished TGF-${\beta}$ expression and fibroblast numbers during the entire 21 day testing period.

• Polymer(Korea)
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• v.26 no.1
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• pp.128-138
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• 2002

1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU, Carmustine)-loaded poly(D, L-lactide-co-glycolide) (PLGA, lactide/glycolide mole ratio 75 : 25) microparticles were prepared and fabricated into wafers in an attempt to study the possibility for the treatment of malignant glioma by direct inserting the wafers to the tumor or the cavity remained after surgical resection of the tumor. SEM observation of the microparticles prepared by spray drying method revealed that the microparticles were spherical, i. e. microspheres. Significant reduction of the crystallinity of BCNU encapsulated in PLGA was confirmed by X-ray diffraction and differential scanning calorimetry analyses of the BCNU-loaded PLGA microparticles. Release pattern of BCNU was dependent on several preparation parameters, such as the molecular weight and concentration of PLGA, and initial BCNU loading amount, etc. In vitro release of BCNU was prolonged over 8 weeks with close to zero-order release pattern after initial burst effect. Observations of morphological change of wafers and pH change of release media during release test period confirmed that hydration and degradation of PLGA would be facilitated with an increase of BCNU-loading amount.

• Journal of the Korean Arthroscopy Society
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• v.16 no.2
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• pp.140-146
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• 2012

Purpose: The objective of this study was to assess the clinical outcome of arthroscopic release of the extensor carpi radialis brevis (ECRB) tendon in chronic recalcitrant lateral epicondylitis and tried to determine any prognostic factors. Materials and Methods: A retrospective review of 24 patients with lateral epicondylitis treated by arthroscopic ECRB release was performed. Outcome measures included a patient self rating and visual analog scale (VAS). Functional evaluation was made with Quick-disabilities of the arm, shoulder and hand (DASH) score system to identify preoperative factors that might be associated with the outcomes. Results: Twenty one (88%) elbows received benefit from the procedure. A mean preoperative VAS pain score and the mean Quick-DASH were significantly improved at final follow up. Age, sex, dominant arm and duration of symptom, presence of capsular tear or calcification did not correlate significantly with the clinical outcome. Three of four patients without T2-weighted high signal focus of the ECRB origin on preoperative magnetic resonance imaging (MRI) showed higher Quick-DASH score. Conclusion: Arthroscopic release of the ECRB is an effective option for chronic recalcitrant lateral epicondylitis. Lack of high signal focus on preoperative MRI is significantly associated with a poor surgical outcome and a considerable factor for the proper surgical indication.

• Journal of Pharmaceutical Investigation
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• v.29 no.1
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• pp.21-27
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• 1999

Semi-solid poly(ortho esters) (POE) were prepared to provide bioerodible carriers for sustained drug delivery systems of naloxone (NLX) in the treatment of narcotic addiction. As the POE have viscous behavior at room temperature, a significant advantage of this polymer is that it can be injected without any surgical intervention. The POE was synthesized by a transesterification reaction between 1,2,6-hexanetriol and trimethyl orthoacetate, and the structure of the polymer was confirmed by IR. The in vitro release of the drug from POE was studied. The release rate of NLX decreased with increasing intrinsic viscosities of the polymer. In vivo biocompatibility studies were carried out in rats with NLX loaded POE. Histopathological analysis showed that NLX implants are well-tolerated by rats when used subcutaneously. Pharmacokinetic studies of POE-NLX implants of two different viscosities were carried out in rabbits. In all cases, plasma concentrations of NLX were maintained over 1 ng/ml for at least 168 hours, but initial burst effect was observed. Mean residence time(MRT) was found to depend on the viscosity of the polymer.

• Journal of Pharmaceutical Investigation
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• v.29 no.2
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• pp.93-98
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• 1999

Semi-solid poly(ortho esters) (POE) were prepared to provide bioerodible carriers for sustained drug delivery systems of nifedipine in the treatment of cardiovascular disease. As the POE has viscous behavior at room temperature, a significant advantage of this polymer is that it can be injected without any surgical intervention. The POE was synthesized by a transesterification reaction between 1,2,6-hexanetriol and trimethyl orthoacetate and the nifedipine release from POE was studied in vitro. The release rate of nifedipine decreased with increasing the amount of nifedipine and the diethanolamine dispersed in the polymer. But the excess amounts, above 3%, of diethanolamine retarded the release of nifedipine. In vivo biocompatibility studies were carried out in rats with nifedipine loaded POE. Histopathological analysis showed that nifedipine loaded POE implants were well-tolerated by rats when used subcutaneously. In case of the rats implanted POE containing diethanolamine, tissue necrosis and inflammation were occured. Pharmacokinetic studies of nifedipine loaded POE implants were carried out in rabbits. In all cases, plasma concentrations of nifedipine were maintained over 15 ng/ml for at least 360 hours and biological half $life(t_{1/2})$ and mean residence time(MRT) were increased by addition of diethanolamine.

• Archives of Craniofacial Surgery
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• v.20 no.4
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• pp.255-259
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• 2019

Craniofacial cleft is a rare disease, and has multiple variations with a wide spectrum of severity. Among several classification systems of craniofacial clefts, the Tessier classification is the most widely used because of its simplicity and treatment-oriented approach. We report the case of a Tessier number 3 cleft with wide soft tissue and skeletal defect that resulted in direct communication among the orbital, maxillary sinus, nasal, and oral cavities. We performed soft tissue reconstruction using the straight-line advanced release technique that was devised for unilateral cleft lip repair. The extension of the lateral mucosal and medial mucosal flaps, the turn over flap from the outward turning lower eyelid, and wide dissection around the orbicularis oris muscle enabled successful soft tissue reconstruction without complications. Through this case, we have proved that the straight-line advanced release technique can be applied to severe craniofacial cleft repair as well as unilateral cleft lip repair.

• Journal of Korean Neurosurgical Society
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• v.65 no.2
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• pp.307-314
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• 2022

Objective : The percutaneous thread transection technique is a surgical dissecting method using a dissecting thread inserted through a needle under ultrasound guidance without skin incision. As the new dissecting threads were developed domestically, this cadaver study was conducted to compare the effectiveness and safety between the new threads (ultra V sswire and smartwire-01) and a pre-existing commercial dissecting thread (loop & shear) by demonstrating a modified looped thread cubital tunnel release. Methods : The percutaneous cubital tunnel release procedure was performed on 29 fresh cadaveric upper extremities. The pre-existing commercial thread was used in 5 upper extremities. The two newly developed threads were used in 24 upper extremities. Two practitioners performed the procedures separately. After the modified looped thread cubital release, anatomical and histological analyses were performed by a blinded anatomist. The presence of the dissected cubital tunnel and damaged adjacent soft tissue was assessed. Results : Out of the 29 cadaveric upper extremities, 27 specimens showed complete dissection of the Osborne ligament and the proximal fascia of the flexor carpi ulnaris muscle. One specimen was incompletely dissected in each of the ultra V sswire and smartwire-01 groups. There were no injuries of adjacent structures including the ulnar nerve, ulnar artery, medial antebrachial cutaneous nerve, or flexor tendon with either the commercial thread or the newly developed threads. The anatomical analysis revealed clear and sharp incisional margins of the cubital tunnel in the Smartwire-01 and loop & shear groups. All three kinds of threads maintained proper linear elasticity for easy handling during the procedure. The smartwire-01 provided higher visibility in ultrasound than the other threads. Conclusion : The newly developed threads were effective and safe for use in the thread cubital tunnel release procedure.

• Korean Journal of Bronchoesophagology
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• v.2 no.1
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• pp.125-128
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• 1996

Tongue tie is the congenital anomaly which is manifested by an abnormally short and thick lingual frenulum so that a condition outside of the range of normal anatomic or functional capability. In general, the surgical correction is the treatment of choice: release of tongue tie and closure. We compared the traditional frenotomy with laser frenotomy using Nd：YAG laser to treat 67 cases of tongue tie during a period of JAN. 1993 through Feb. 1996. The advantages of laser frenotomy were decreased blood loss and operation time. So we had a conclusion as the adequate use of laser frenotomy with suture was a good surgical procedure for correction of tongue tie.

• Archives of Plastic Surgery
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• v.39 no.4
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• pp.426-430
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• 2012

Dupuytren's contracture is a condition commonly encountered by hand surgeons, although it is rare in the Asian population. Various surgical procedures for Dupuytren's contracture have been reported, and the outcomes vary according to the treatment modalities. We report the treatment results of segmental fasciectomies with multiple transverse incisions for patients with Dupuytren's contracture. The cases of seven patients who underwent multiple segmental fasciectomies with multiple transverse incisions for Dupuytren's contracture from 2006 to 2011 were reviewed retrospectively. Multiple transverse incisions to the severe contracture sites were performed initially, and additional incisions to the metacarpophalangeal (MCP) joints, and the proximal interphalangeal (PIP) joints were performed if necessary. Segmental fasciectomies by removing the fibromatous nodules or cords between the incision lines were performed and the wound margins were approximated. The mean range of motion of the involved MCP joints and PIP joints was fully recovered. During the follow-up periods, there was no evidence of recurrence or progression of disease. Multiple transverse incisions for Dupuytren's contracture are technically challenging, and require a high skill level of hand surgeons. However, we achieved excellent correction of contractures with no associated complications. Therefore, segmental fasciectomies with multiple transverse incisions can be a good treatment option for Dupuytren's contracture.

• Journal of Korean Neurosurgical Society
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• v.63 no.1
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• pp.45-55
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• 2020

Objective : Fibrin sealants have been used for hemostasis, sealant for cerebrospinal fluid leakage, and adhesive barrier in neurosurgery. Further, as its clinical use and role of an effective drug delivery vehicle have been proposed. This study was performed to measure antibacterial activity and continuous local antibiotic release from different concentrations of vancomycin-impregnated fibrin sealant in vitro. Methods : Antibacterial activity was investigated by disk diffusion test by measuring the diameter of the growth inhibition zone of bacteria (methicillin-resistant Staphylococcus aureus, ATCC29213) from vancomycin-embedded fibrin sealant disc diluted at five different concentrations (C1-C5; 8.33, 4.167, 0.83, 0.083, and 0.0083 mg/disc, respectively). Continuous and conditioned release of vancomycin concentration (for 2 weeks and for 5 days, respectively) were also measured using high-performance liquid chromatography (HPLC) method. To mimic the physiologic wound conditions with in vitro, conditioned vancomycin release in phosphate buffer solution (PBS) was measured and replaced PBS for five consecutive days, half a day or completely daily. Results : In the disk diffusion test, the mean diameters of bacterial inhibition zone were 2.54±0.07 cm, 2.61±0.12 cm, and 2.13±0.15 cm (C1, C2, and C3 respectively) but 1.67±0.06 cm and 1.23±0.15 cm in C4 and C5, respectively. Continuous elution test elicited the peak release of vancomycin from the fibrin sealant at 48 hours, with continued release until 2 weeks. However, conditioned vancomycin release decreased to half or more on day 2, however, the sustainable release was measured over the therapeutic dose (10-20 ㎍/mL) for 5 days and 4 days in assays of half and total exchange of PBS. Conclusion : This study suggests that fibrin sealant can provide an efficient vehicle for antibiotic drug release in a wide range of neurosurgical procedures and the safe and effective therapeutic dose will be at the concentration embedded of 4.167 mg/disc or more of vancomycin.