Migration of Penrose Drain Following Anterior Cervical Spinal Surgery / 대한정형외과학회잡지

A retained surgical drain in the operation site is a rare complication that may cause clinical problems and result in medical disputes.The discovery of a retained drain is most often reported after abdominal and pelvis surgery but drain migration in the prevertebral space after anterior cervical spine surgery has not been reported. This paper reports a case of drain retained and migrated into the thorax level following anterior cervical spine surgery with a review of the relevant literature.

Helical Blade Locking Sleeve Disassembly Following Failed Femur Intertrochanter Fracture

A helical blade type of hip screw is used widely for the operative management of femoral trochanteric fractures. A 73-year-old female patient was admitted for femoral trochanteric fracture AO/OTA type 31A2.2. A helical blade locking sleeve dissembled 18 weeks after surgery did not achieve accurate reduction. The patient underwent bipolar hip hemiarthroplasty because the fracture reduction was lost, and it was impossible to remove the remaining helical blade without bone loss. The authors report this case of a rare complication of helical blade.

Injury of the Ascending Branch of the Lateral Femoral Circumflex Artery Caused by a Spike of the Displaced Lesser Trochanter in an Intertrochanteric Femoral Fracture - A Case Report -

Although vascular injuries associated with femoral intertrochanteric fractures have been reported infrequently, bleeding due to vascular injury can lead to severe complications that can be potentially life and limb-threatening. The authors report a case of an injury of the ascending branch of the lateral femoral convolutional artery in a patient who underwent surgical treatment for a femoral intertrochanteric fracture. Vascular injury occurred due to the sharp margin of displaced lesser trochanter five weeks after surgery. Percutaneous transcatheter embolization was done and improved without additional complications. Therefore, the surgeons need to be aware of possible associated vascular injuries caused by displaced lesser trochanter fragments in femoral intertrochanteric fractures.

Helical Blade Locking Sleeve Disassembly Following Failed Femur Intertrochanter Fracture

A helical blade type of hip screw is used widely for the operative management of femoral trochanteric fractures. A 73-year-old female patient was admitted for femoral trochanteric fracture AO/OTA type 31A2.2. A helical blade locking sleeve dissembled 18 weeks after surgery did not achieve accurate reduction. The patient underwent bipolar hip hemiarthroplasty because the fracture reduction was lost, and it was impossible to remove the remaining helical blade without bone loss. The authors report this case of a rare complication of helical blade.

Injury of the Ascending Branch of the Lateral Femoral Circumflex Artery Caused by a Spike of the Displaced Lesser Trochanter in an Intertrochanteric Femoral Fracture - A Case Report -

Although vascular injuries associated with femoral intertrochanteric fractures have been reported infrequently, bleeding due to vascular injury can lead to severe complications that can be potentially life and limb-threatening. The authors report a case of an injury of the ascending branch of the lateral femoral convolutional artery in a patient who underwent surgical treatment for a femoral intertrochanteric fracture. Vascular injury occurred due to the sharp margin of displaced lesser trochanter five weeks after surgery. Percutaneous transcatheter embolization was done and improved without additional complications. Therefore, the surgeons need to be aware of possible associated vascular injuries caused by displaced lesser trochanter fragments in femoral intertrochanteric fractures.

Arthroscopic Iliopsoas Tenotomy of Iliopsoas Impingement after Total Hip Arthroplasty / 대한정형외과학회잡지

Purpose@#The clinical outcomes were investigated to determine if arthroscopic management is a useful method for 19 hips with iliopsoas tendon impingement (IPI) after total hip arthroplasty (THA). @*Materials and Methods@#Eighteen patients (19 hips), who complained of groin pain and flexion pain that persisted after THA from September 2013 to December 2019, were the subjects of this investigation. The mean time to manifestation after THA was four months (range, 1–9 months) in patients of an average age of 60 years (range, 50–69 years). Thirteen out of 18 patients underwent THA using the direct anterior approach and five by the lateral approach. IPI was diagnosed by the medical history, physical examination, blood test, radiographic examination using X-ray and computed tomography, and topical injection therapy. All patients underwent arthroscopic treatment and a dynamic arthroscopic physical examination after exposure to the iliopsoas tendon revealed impingement. Tenotomy was then performed on the muscle portion through the total tendon portion. Symptoms and pain levels of preoperative, postoperative and follow-up period were investigated and compared. @*Results@#The Western Ontario and McMaster Universities Osteoarthritis Index score decreased from an average of 58.4 (range, 40–88) before surgery to an average of 35.0 (range, 15–76) after surgery. Similarly, the visual analogue scale decreased from an average of 4.0 (range, 2–6) before surgery to an average of 1.4 (range, 0–4) after surgery. Sixteen patients (88.9%) showed pain relief and improvement in the straight leg raise test, and two patients showed postoperative muscle weakness and sustained pain. In the follow-up period, muscle weakness improved. One patient underwent arthroscopic iliopsoas tenotomy at the lesser trochanteric level but the symptoms persisted.The clinical symptoms were improved after one more tenotomy at the joint level. @*Conclusion@#Arthroscopic iliopsoas tenotomy performed in patients with IPI after THA showed good clinical results.

Survival Analysis of Patients with Alzheimer’s Disease: A Study Based on Data from the Korean National Health Insurance Services’ Senior Cohort Database / 가정의학회지

Background@#Korea’s rapidly aging population has experienced a sharp rise in the prevalence of dementia. Patients with Alzheimer’s disease (AD), which is estimated to be about three-quarters of all patients with dementia, tend to have higher mortality rates compared with patients without Alzheimer’s disease. In this study, a survival analysis of patients with AD was conducted in order to provide knowledge to those who provide medical care to these patients. @*Methods@#Data on individuals over 65 years old in 2004 were extracted from the Korean National Health Insurance Services’ Senior Cohort database (2002–2013). The subjects were 209,254 patients, including 2,695 who were first diagnosed with AD (the AD group) and 206,559 that had not been diagnosed with the disease (non-AD group). To investigate the independent effect of AD on survival, the Cox proportional-hazards model, hazard ratios (confidence interval of 95%), and the Kaplan-Meier method were used. @*Results@#Mean survival time in the AD group was 5.3±3.3 years, which was about 2.5 years shorter than that in the non-AD group (7.8±2.4 years). The mortality rate in the AD group (66.3%) was higher than that in the non-AD group (26.3%). The adjusted hazard ratio in the AD group was 2.5 and, therefore, it was found that the AD group had a 2.5-fold higher risk of death than the non-AD group. @*Conclusion@#Overall, AD has a large, independent impact on survival. Survival time was shorter, and the mortality rate and risk were generally higher in the AD group, compared with the non-AD group.

Development and implementation of standardized method for detecting immunogenicity of acellular pertussis vaccines in Korea

PURPOSE: There is no standard method for confirming the immunogenicity of acellular pertussis vaccines. We tried to develop a local standard method for evaluating the immunogenicity of the three-component of acellular pertussis vaccines which was developed by a Korean local company. MATERIALS AND METHODS: The developed pertussis antigens (pertussis toxin, filamentous hemagglutinin, pertactin) were evaluated by in-house enzyme-linked immunosorbent assay (ELISA) using 189 negative sera, 25 positive sera, and 73 paired sera (pre- and post-Tdap [tetanus, diphtheria, and acellular pertussis] vaccinated sera). ELISA units were calculated by the reference line method, compared with World Health Organization reference sera, and the cut-off value was calculated using negative sera. RESULTS: When compared to National Institute for Biological Standards and Control control antigen (NIBSC) control antigens, the developed pertussis toxin (PT) and filamentous haemagglutinin (FHA) antigens were 203.48 and 61.60 IU/µg, respectively. Each in-house ELISA was established by validating the coefficients of variation % (PT, 11.53%; FHA, 8.60%; pertactin [PRN], 9.86%) obtained from the results of inter- and intra-assay variation. Also, the cut-off values of PT, FHA, and PRN were 11.65, 38.95, and 5.66 EU/mL, respectively. The distributions of antibody levels in paired showed that 93.15% (68/73) in anti-PT IgG, 97.26% (72/73) in anti-FHA IgG, and 100% in anti-PRN IgG were higher than a 100% increase after vaccination. Additionally, the values of 89.04% (65/73) in anti-PT IgG, 97.26% (72/73) in anti-FHA IgG, and 100% in anti-PRN IgG were below each cut-off point. CONCLUSION: We established an in-house ELISA method using self-developed antigens, and these immunoassays have provided a way to standardize measuring the immunogenicity of newly developed vaccines, through single- and dual-serology.

Enzyme-linked immunosorbent assay for detecting anti-pertussis toxin antibody in mouse

PURPOSE: Although the DTaP and Tdap vaccines used to prevent pertussis have been used for a long time, there is no standard method for measuring pertussis antigens. Therefore, this preliminary study was conducted to develop an enzyme-linked immunosorbent assay method using an animal model for measuring antibodies against pertussis toxin, the most important pertussis pathogenic antigen, in the sera of vaccinated mice. MATERIALS AND METHODS: Bordetella pertussis Tohama phase I was cultured for 24–30 hours, and then pertussis toxin was purified from the culture medium by chromatography. Purified pertussis toxin was diluted in phosphate-buffered saline-coating buffer, and 100 µL of diluted pertussis toxin was added to each well and reacted at room temperature for 4 hours. Positive serum was diluted to 1/1,250–1/80,000 and negative serum was diluted to 1/50 to determine the coating concentration with the optimal signal/noise ratio. Optimal test conditions were confirmed from the dilution factors of the secondary antibody and streptavidin horseradish peroxidase (SA-HRP). RESULTS: Optimal conditions were as follows: 4 µg/mL for coating antigen; 1/40,000 for secondary antibody; and 1/1,000 for the SA-HRP dilution factor. Comparison of the sera obtained from mice treated with a developing vaccine and commercial vaccine with National Institute for Biological Standard and Control standard serum under the established conditions showed the following results: 1,300.62, 534.94, and 34.85, respectively. CONCLUSION: The method developed in this study is suitable for measuring anti-pertussis toxin antibodies and may be applicable for clinical sample analysis or indirect diagnosis of pertussis.

Hemarthrosis Occurred after Arthroscopic Rotator Cuff Repair in a Chronic Renal Failure Patient with a Stenosis in an Ipsilateral Arteriovenous Fistula / 대한정형외과학회잡지

Hemarthrosis occurring after arthroscopic surgery for lesions of the shoulder joint is a very rare complication that can develop due to an injury to the blood vessels when an anterior portal is formed. This is a complication that rarely develops in patients who are taking antithrombotic drugs or who do not have associated diseases, such as thrombocytopenia. We report a case of hemarthrosis that occurred after performing arthroscopic surgery to repair a rotator cuff tear in a patient with a stenosis in an arteriovenous fistula for hemodialysis in the ipsilateral upper arm.

Delayed Rupture of the Extensor Pollicis Longus Tendon Following Intramedullary Nailing of Radial Shaft Fracture / 대한정형외과학회잡지

Delayed rupture of the extensor pollicis longus tendon mostly occur after plate fixation of distal radius fracture. However, delayed rupture of the extensor pollcis longus tendon following intramedullary nailing of radial shaft fracture is very rare. We report one case of delayed rupture of the extensor pollicis longus tendon following intramedullary nailing, presenting abnormal signs from adhesion of the extensor pollicis longus with extensor indicis at the nail insertion site.

Arthroscopic Reduction and Transportal Screw Fixation of Acetabular Posterior Wall Fracture: Technical Note / 대한고관절학회지

Acetabular fractures can be treated with variable method. In this study, acetabular posterior wall fracture was treated with arthroscopic reduction and fixation using cannulated screw. The patient recovered immediately and had a satisfactory outcome. In some case of acetabular fracture could be good indication with additional advantages of joint debridement and loose body removal. So, we report our case with technical note.

Preliminary study on the immunogenicity of a newly developed GCC Tdap vaccine and its protection efficacy against Bordetella pertussis in a murine intranasal challenge model

PURPOSE: Active reduced dose tetanus-diphtheria-acellular pertussis (Tdap) vaccination for adolescents and adults is necessary because waning immunity after primary diphtheria-tetanus-pertussis vaccination is related to the recent emergence of pertussis. This study was conducted to compare the immunogenicity and protection efficacy against Bordetella pertussis between a new GCC Tdap vaccine and a commercially available Tdap vaccine in a murine model. MATERIALS AND METHODS: BALB/c mice were immunized with two doses of diphtheria-tetanus-acellular pertussis (DTaP) vaccine for priming and a subsequent Tdap booster vaccination. According to the type of booster vaccine, mice were divided into four groups: commercially available Tdap vaccine in group 1 and GCC Tdap vaccines of different combinations of pertussis antigens in groups 2 to 4. Humoral and cell-mediated immune responses and protection efficacy using a murine intranasal challenge model after booster vaccination were compared among the four groups. RESULTS: Every group showed significant increases in antibody titers against pertussis antigens such as pertussis toxin, filamentous hemagglutinin, and pertactin after booster vaccination. Spleen cells showed both Th1 and Th2 cell-mediated immune responses stimulated by pertussis antigens in all groups without any significant difference. In the intranasal B. pertussis infection model, bacteria were eradicated in all groups five days after challenge infection. CONCLUSION: This preliminary study did not show significantly different immunogenicity or protection efficacy of the new GCC Tdap vaccines compared to the commercially available Tdap vaccine, although a more extensive study is necessary to assess the differing efficacies of the new GCC Tdap vaccines.

Survey of the Application of the Korean Clinical Practice Recommendations on Breast Cancer Treatment: The Utility of the Korean Breast Cancer Society Guidelines / 한국유방암학회지

This survey was performed to analyze the usability of the third edition of the Korean breast cancer clinical practice guidelines (KBCCPG) in clinical practice. We made a questionnaire composed of 18 general and 82 specific questions regarding benign breast disease (B; 1 question); non-invasive disease (N; 12 questions); early-stage disease (E; 26 questions); advanced disease (A; 24 questions); and metastatic (M) breast cancer-related problems (19 questions). A total of 100 questionnaires, with a link to an online survey, were delivered via e-mail to over 700 members of the Korean Breast Cancer Society (KBCS), and associated academy members, over 20 days between 26th February and 16th May 2010. Out of 270 respondents who read the e-mail, 96 answered the questionnaire. Participants included 87 surgical oncologists, 5 radiation oncologists, 2 oncoplastic surgeons, 1 pathologist, and 1 medical oncologist. The third KBCCPG were perceived as differing from the second guidelines in terms of the level of clinical evidence required before choosing a recommendation. For the progress of the KBCCPG, the guideline committee should try to reinforce all courses of guideline development with several elements including data from clinical trials of Korean breast cancer patients, securing a multidisciplinary approach, developing consistent and reasonable processes for each step of the revision of the guidelines, induction of liberal scientific and ethical discussion about all issues with all KBCS members. The cost-effectiveness of healthcare and the logical development of the KBCCPG would also be ensured. Timely updates of the clinical guidelines for breast cancer treatment are essential to facilitate optimal decision-making in daily practice, and to ensure adequate patient feedback.

Development and Validation of a Korean Version of the Premature Ejaculation Diagnostic Tool (PEDT) / 대한남성과학회지

PROPOSE: Premature ejaculation (PE) is the most prevalent male ejaculation disorder. The premature ejaculation diagnostic tool (PEDT) was developed to systematically apply the DSM-IV-TR criteria in diagnostic PE. This study was designed to assess the validity of the Korean version of the PEDT as a diagnostic tool for PE. MATERIALS AND METHODS: The Korean version development of the PDET involved two stages: (1) Development of the initial language version through two independent forward translations and one backward translation. Discrepancies between the original English form and the first draft Korean translation were reviewed by the panel. Discrepancies between the original English form and the Korean translation were reviewed by the panel. (2) For psychometric validation and scoring system development, data was collected from men with and without PE based on clinician diagnosis, using DSM-IV-TR criteria. A total of 98 patients with a DSM-IV-TR defined PE and 100 men without PE were enrolled into the study and requested to complete the PEDT, which was translated into Korean. The PE patients were also requested to measure intravaginal ejaculatory latency time (IELT). The 50 men of no-PE group and all PE group were requested to come for a second visit to assess the PEDT's retest reliability. The results were analyzed statistically by SPSS version 12. RESULT: The mean age of the no-PE group and PE group were 43.4+/-9.2 and 51.6+/-9.0, respectively. The geometric mean IELT of the PE group was 115.37+/-78.14s. The number of men reporting IELTs of 2min were 28 (28.6%), 29 (29.6%) and 41 (41.8%), respectively. The Cronbach's alpha score of the Korean version of PEDT was calculated as 0.93, showing adequate internal consistency. The test-retest correlation coefficients of each item were higher than 0.72 and the correlation coefficients of the total score was 0.88. (P or =11 PE. CONCLUSIONS: The Korean version of PEDT was highly effective in detecting the presence of PE. The result of our study supports its validity as a diagnostic instrument in the clinical setting.

Endoscopic Spinal Surgery for Herniated Lumbar Discs

OBJECTIVE: So called "minimally invasive procedures" have evolved from chemonucleolysis, automated percutaneous discectomy, arthroscopic microdiscectomy that are mainly working within the confines of intradiscal space to transforaminal endoscopic technique to remove herniated epidural disc materials directly. The purpose of this study is to assess the result of endoscopic spinal surgery and favorable indications in the thoracolumbar spine. METHODS: The records of 71 patients, 73 endoscopic procedures, were retrospectively analysed. Yeung Endoscopic Spine Surgery system with 7 mm working sleeve and 25degrees viewing angle was used. The mean follow up period was 6 months (range,3-9). RESULTS: Operated levels were from T12-L1 disc down to L5-L6 or S1 disc. Of 71 cases, 2 patients underwent transforaminal endoscopic surgery twice due to recurrence after initial operation. MacNab's criteria was used to assess the outcome. Favorable outcome, excellent or good, was seen in 78% (57 procedures) of the patients. Among 11 fair outcomes, only 1 procedure was followed by secondary open procedure, laminectomy with discectomy. Two of 5 poor outcomes were operated again by same procedure which resulted in fair outcomes. One patient with aggravated cauda equina syndrome remained poor and a lumbar fusion procedure was performed in other patient with poor outcome. There were 2 postoperative discitis that were treated with conservative care in one and anterior lumbar interbody fusion in the other. CONCLUSION: Evolving technology of mechanical, visual instrument enables minimal invasive procedure possible and effective. The transforaminal endoscopic spinal surgery can reach as high as T12-L1 disc level. The rate of favorable outcome is mid-range among reported endoscopic lumbar surgery series. Authors believe that the outcome will be better as cases accumulate and will be able to reach the rate of standard open microsurgery.

Clinical and Functional Assessment after Anticoagulant Therapy of Acute Deep Vein Thrombosis Involving the Lower Limb

We assessed the clinical status after anticoagulant therapy in acute deep vein thrombosis (DVT) involving the lower limbs. Between 1994 and 2001, 139 patients suffering from acute DVT were treated with heparin therapy followed by oral anticoagulant therapy. The coagulation factor assay was done prior to any anticoagulation therapy. The duplex scan was checked serially. The mean follow-up periods was 32 ± 19 months. There were 32 (23.0%) cases of protein C deficiency, 12 (8.6%) cases of protein S deficiency, 13 (9.4%) cases of AT-III deficiency and 11 (7.9%) cases of abnormal plasminogen level. Fourteen cases had coagulation factor abnormalities within the family. The initial lung scan showed 29 (20.9%) cases with high, 13 (9.4%) cases with intermediate and 70 (50.4%) cases with a low probability of pulmonary embolism (PE) developing. During the follow-up periods, there were 3 cases of non-fatal PE documented with chest CT scan. The patients were divided according to the extent of the thrombus; Group I (38 cases) was limited to the infrainguinal deep vein, Group II (70 cases) extended to the iliac vein and Group III (9 cases) extended to the vena cava. Partial lysis occurred in 20/35/3 (52.6/50.0/33.3%) cases and no change in 10/24/6 (26.3/ 34.3/ 66.7%) cases in Groups I/ II/ III, respectively. Deep vein valvular reflux occurred in 15/25/5 (39.5/35.7/55.6%) cases in Groups I/ II/ III, respectively. With anticoagulation therapy, most of the thrombi remained in unresolved states and there was a high rate of deep vein valvular reflux. However, there was no serious complications which affected the patients' quality of life.

Clinical Experiences of Lower Limb Amputation in Ischemic Arterial Disease

PURPOSE: Despite the decrease in the number of lower limb amputation in ischemic limb patients as a result of advances in vascular reconstruction surgery, amputation still plays an important role in the management of end-stage peripheral vascular disease. Owing to the importance of the amputation level in postoperative rehabilitation and prevention of reamputation, there have been many reports defining theses level. Clinical characteristics were determined by retrospectively reviewing medical records of patients who underwent lower limb amputation for peripheral vascular disease. METHOD: Between June 1997 and September 2002, lower limb amputation was performed in 73 patients with peripheral vascular disease. RESULT: Mean follow-up period was 15 months; male to female ratio was 7.1 to 1; and mean age was 62.6 years. Associated diseases included DM (39 patients), hypertension (15 patients), ischemic heart disease (13 patients), and cerebrovascular disease (6 patients). Etiologies were atherosclerosis in 47.9%, Buerger's disease in 15.1%, DM foot in 13.7%, acute arterial embolization in 2.7%, ruptured abdominal aortic aneurysm in 1.4%, and combined atherosclerosis with DM foot in 19.2%. Bypass surgery was performed in 24 cases and only 4 cases underwent radiologic vascular intervention. The frequency of amputation was one surgery in 50 cases and more than two surgeries in 23 cases. Amputation level was digit amputation in 49 cases (67.1%), transmetatarsal in 10 cases (13.7%), below-knee in 11 cases (15.1%) and above-knee in 3 cases (4.1%). In 73 cases, reamputation was performed in 19 cases (26%) for poor stump wound healing. The cause of reamputation was atherosclerosis in 17.1%, Buerger's disease in 27.3%, DM foot in 60.0% and combined atherosclerosis with DM foot in 28.6%; the reamputation rate was the highest in DM foot patients. Bypass surgery for improved blood flow in the stump was performed in 24 cases, among these cases, reamputation was performed in 2 cases (8.3%). CONCLUSION: Amputation in ischemic limb patients was most commonly performed in artherosclerosis patients and the most common amputation level was digit. The reamputation rate was the highest in DM foot patients; a more careful selection of the amputation level in DM foot patients may be needed.

Implication of Lymphatic or Blood Vessel Invasion in Early Gastric Cancer

PURPOSE: Various types of minimally invasive therapy have been attempted for early gastric cancer (EGC) patients. However, minimally invasive therapy can not fully evaluate the nodal status which has been suggested as an important prognostic factor for EGC patients. This study was conducted to evaluate the clinical implications and prognostic impact of lymphatic or blood vessel invasion (LBVI) in EGC patients in the era of minimally invasive therapy. METHODS: A total of 566 EGC patients who had undergone gastrectomy with D2 or more extended lymphadenectomy between July 1993 and December 1997 were retrospectively reviewed. The risk factors that determine LBVI and the clinicopathological features, recurrence rates, and prognoses according to LBVI were investigated by univariate and multivariate analyses. RESULTS: Lymphatic vessel invasion was noted in 59 patients (10.4%); blood vessel invasion in 13 patients (2.3%); LBVI in 61 patients (10.8%). LBVI was associated with submucosal invasion, larger tumor size, and elevated macroscopic type (P<0.05). LBVI and lymph node metastasis were found to be significantly correlated. LBVI was an independent risk factor for lymph node metastasis (relative risk 26.56, 95% confidence interval 12.77-55.23). Patients with LBVI had a recurrence rate of 15.3% while patients without LBVI had a 3.7% recurrence rate (P<0.01). The overall and disease-specific 5-year survival rates were 79.9 and 85.9% for patients with LBVI whereas they were 93.4 and 97.5% for patients without LBVI (P<0.01, respectively). On multivariate analysis, LBVI was an independent risk factor for poor prognosis (relative risk 2.38, 95% confidence interval 1.15-4.93). CONCLUSION: Lymphatic or blood vessel invasion is an adverse prognostic indicator for EGC patients. Considering the low rate of lymph node metastasis and recurrence in patients with LBVI negative EGC, minimally invasive therapy can be regarded as curative when LBVI is negative.

Surgical Experience of Carotid Pseudoaneurysm

An extracranial carotid artery pseudoaneurysm is a rare condition that is caused by various types of arteritis, trauma and infectious causes. Generally, a pseudoaneurysm may be difficult to treat surgically when dissecting the paraaeurysmal fibrotic dense inflammatory tissues. The surgical management of a peudoaneurysm of the carotid artery involves a risk of nerve and arterial injury. This paper reports the repair of a carotid artery pseudoaneurysm after the proximal and distal control of the internal carotid artery using a Pruitt-Inahara shunt (P-I shunt) and the distal control of the external carotid artery using a small sized occlusion balloon catheter.