ABSTRACT
Eukaryotic cells use conserved quality control mechanisms to repair or degrade defective proteins, which are synthesized at a high rate during proteotoxic stress. Quality control mechanisms include molecular chaperones, the ubiquitin-proteasome system, and autophagic machinery. Recent research reveals that during autophagy, membrane-bound organelles are selectively sequestered and degraded. Selective autophagy is also critical for the clearance of excess or damaged protein complexes (e.g., proteasomes and ribosomes) and membrane-less compartments (e.g., protein aggregates and ribonucleoprotein granules). As sessile organisms, plants rely on quality control mechanisms for their adaptation to fluctuating environments. In this mini-review, we highlight recent work elucidating the roles of selective autophagy in the quality control of proteins and RNA in plant cells. Emphasis will be placed on selective degradation of membrane-less compartments and protein complexes in the cytoplasm. We also propose possible mechanisms by which defective proteins are selectively recognized by autophagic machinery.
Subject(s)
Plant Cells/physiology , Plant Proteins/standards , RNA, Plant/standards , Autophagy , Gene Expression Regulation, PlantABSTRACT
This retrospective clinical study was performed to evaluate whether a visual or quantitative method is more valuable for assessing painful temporomandibular disorder (TMD) using bone scintigraphy results.In total, 230 patients (172 women and 58 men) with TMD were enrolled. All patients were questioned about their temporomandibular joint (TMJ) pain. Bone scintigraphic data were acquired in all patients, and images were analyzed by visual and quantitative methods using the TMJ-to-skull uptake ratio. The diagnostic performances of both bone scintigraphic assessment methods for painful TMD were compared.In total, 241 of 460 TMJs (52.4%) were finally diagnosed with painful TMD. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the visual analysis for diagnosing painful TMD were 62.8%, 59.6%, 58.6%, 63.8%, and 61.1%, respectively. The quantitative assessment showed the ability to diagnose painful TMD with a sensitivity of 58.8% and specificity of 69.3%. The diagnostic ability of the visual analysis for diagnosing painful TMD was not significantly different from that of the quantitative analysis.Visual bone scintigraphic analysis showed a diagnostic utility similar to that of quantitative assessment for the diagnosis of painful TMD.
Subject(s)
Positron-Emission Tomography/methods , Temporomandibular Joint Disorders/diagnostic imaging , Temporomandibular Joint/physiopathology , Adolescent , Adult , Aged , Area Under Curve , Cohort Studies , Evaluation Studies as Topic , Female , Humans , Male , Middle Aged , Pain Measurement , Physical Examination/methods , ROC Curve , Retrospective Studies , Severity of Illness Index , Temporomandibular Joint Disorders/diagnosis , Young AdultABSTRACT
An 84-year-old female patient with known Sjögren syndrome underwent 18F-FDG PET/CT to detect recurrence of uterine cervix cancer. Sjögren syndrome is autoimmune disease that typically produces symptoms of dry mouth and eyes. We report a case of physiologic 18F-FDG uptake on facial muscles by chewing-like habitual movement, which was confused with salivary retention at first. The physiologic FDG uptake in oral cavity and facial muscles has to be reviewed carefully not to be confused with abnormal uptake.
Subject(s)
Facial Muscles/diagnostic imaging , Fluorodeoxyglucose F18 , Mastication , Positron-Emission Tomography , Radiopharmaceuticals , Sjogren's Syndrome/diagnostic imaging , Tomography, X-Ray Computed , Aged, 80 and over , Diagnosis, Differential , Female , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Multimodal Imaging , Neoplasm Recurrence, Local/complications , Neoplasm Recurrence, Local/diagnostic imaging , Radiopharmaceuticals/pharmacokinetics , Sjogren's Syndrome/complications , Uterine Neoplasms/complications , Uterine Neoplasms/diagnostic imagingABSTRACT
PURPOSE: We investigated whether (131)I whole-body scintigraphy could predict functional changes in salivary glands after radioiodine therapy. METHODS: We evaluated 90 patients who received initial high-dose (≥3.7 GBq) radioiodine therapy after total thyroidectomy. All patients underwent diagnostic (DWS) and post-ablation (TWS) (131)I whole-body scintigraphy. Visual assessment of salivary radioiodine retention on DWS and TWS was used to divide the patients into two types of groups: a DWS+ or DWS- group and a TWS+ or TWS- group. Salivary gland scintigraphy was also performed before DWS and at the first follow-up visit. Peak uptake and %washout were calculated in ROIs of each gland. Functional changes (Δuptake or Δwashout) of salivary glands after radioiodine therapy were compared between the two groups. RESULTS: Both peak uptake and the %washout of the parotid glands were significantly lower after radioiodine therapy (all p values <0.001), whereas only the %washout were significantly reduced in the submandibular glands (all p values <0.05). For the parotid glands, the TWS+ group showed larger Δuptake and Δwashout after radioiodine therapy than did the TWS- group (all p values <0.01). In contrast, the Δuptake and Δwashout of the submandibular glands did not significantly differ between the TWS+ and TWS- groups (all p values >0.05). Likewise, no differences in Δuptake or Δwashout were apparent between the DWS+ and DWS- groups in either the parotid or submandibular glands (all p values >0.05). CONCLUSION: Salivary gland radioiodine retention on post-ablation (131)I scintigraphy is a good predictor of functional impairment of the parotid glands after high-dose radioiodine therapy.
ABSTRACT
We present a novel approach for computing link-based similarities among objects accurately by utilizing the link information pertaining to the objects involved. We discuss the problems with previous link-based similarity measures and propose a novel approach for computing link based similarities that does not suffer from these problems. In the proposed approach each target object is represented by a vector. Each element of the vector corresponds to all the objects in the given data, and the value of each element denotes the weight for the corresponding object. As for this weight value, we propose to utilize the probability of reaching from the target object to the specific object, computed using the "Random Walk with Restart" strategy. Then, we define the similarity between two objects as the cosine similarity of the two vectors. In this paper, we provide examples to show that our approach does not suffer from the aforementioned problems. We also evaluate the performance of the proposed methods in comparison with existing link-based measures, qualitatively and quantitatively, with respect to two kinds of data sets, scientific papers and Web documents. Our experimental results indicate that the proposed methods significantly outperform the existing measures.
Subject(s)
Computer SimulationABSTRACT
We report a case of isolated splenic metastasis from ovarian cancer detected with 18F-FDG PET/CT. A 66-year-old woman with ovarian cancer was referred for 18F-FDG PET/CT to determine the cause of elevated serum CA-125 levels about 48 months after surgery. 18F-FDG PET/CT showed focal, intense uptake in the spleen, with no other abnormal findings. A splenectomy was performed, and the lesion was confirmed as metastasis from ovarian cancer pathologically.
Subject(s)
Fluorodeoxyglucose F18 , Multimodal Imaging , Ovarian Neoplasms/pathology , Positron-Emission Tomography , Splenic Neoplasms/diagnosis , Splenic Neoplasms/secondary , Tomography, X-Ray Computed , Aged , Female , Humans , Splenic Neoplasms/diagnostic imagingABSTRACT
Mediastinal inflammatory pseudotumor is a rare benign disease with its capability for local invasion and rapid growth. We present a case of middle-mediastinal inflammatory pseudotumor and report its contrast-enhanced chest computed tomography, (18)F-fluorodeoxyglucose positron emission tomography/computed tomography and pathologic findings.
Subject(s)
Fluorodeoxyglucose F18 , Granuloma, Plasma Cell/diagnosis , Mediastinal Diseases/diagnosis , Positron-Emission Tomography/methods , Radiopharmaceuticals , Tomography, X-Ray Computed/methods , Adult , Diagnosis, Differential , Humans , MaleABSTRACT
BACKGROUND: Intractable chronic scalp ulcers with cranial bone exposure can occur along the incision after cranioplasty, posing challenges for clinicians. They occur as a result of severe scarring, poor blood circulation of the scalp, and focal osteomyelitis. We successfully repaired these scalp ulcers using a vascularized bipedicled pericranial flap after complete debridement. METHODS: Six patients who underwent cranioplasty had chronic ulcers where the cranial bone, with or without the metal plate, was exposed along the incision line. After completely excising the ulcer and the adjacent scar tissue, subgaleal dissection was performed. We removed the osteomyelitic calvarial bone, the exposed metal plate, and granulation tissue. A bipedicled pericranial flap was elevated to cover the defect between the bone graft or prosthesis and the normal cranial bone. It was transposed to the defect site and fixed using an absorbable suture. Scalp flaps were bilaterally advanced after relaxation incisions on the galea, and were closed without tension. RESULTS: All the surgical wounds were completely healed with an improved aesthetic outcome, and there were no notable complications during a mean follow-up period of seven months. CONCLUSIONS: A bipedicled pericranial flap is vascularized, prompting wound healing without donor site morbidity. This may be an effective modality for treating chronic scalp ulcer accompanied by the exposure of the cranial bone after cranioplasty.
ABSTRACT
After total thyroidectomy for papillary thyroid carcinoma, a 37-year-old woman underwent a 2-mCi (131)I whole-body scan which demonstrated focal uptake in the anterior neck and in the oropharynx. Preoperative contrast-enhanced neck computed tomography demonstrated a small enhancing nodule typical for ectopic thyroid at the tongue base. She was then treated with 150 mCi (131)I. Small asymptomatic lingual thyroid remnants typically do not affect high-dose (131)I therapy.
Subject(s)
Lingual Thyroid/diagnosis , Lingual Thyroid/surgery , Oropharynx/metabolism , Thyroidectomy , Whole Body Imaging , Adult , Biological Transport , Female , Humans , Iodine Radioisotopes/metabolism , Lingual Thyroid/metabolismABSTRACT
OBJECTIVE: It is known that the poor image quality of (18)F-fluorodeoxyglucose ((18)F-FDG) PET scans leads to interpretation difficulty in patients with uncontrolled diabetes mellitus (DM). We usually delay (18)F-FDG PET examination when patients show high glucose levels. This study was performed to evaluate the usefulness and effects of ultrashort-acting insulin on (18)F-FDG PET/computed tomography (CT) imaging in DM patients. MATERIALS AND METHODS: A total of 105 DM patients (68 men and 37 women) were included. Ultrashort-acting insulin was intravenously injected when patients showed high glucose levels (>190 mg/dl). (18)F-FDG was injected 60 min after ultrashort-acting insulin injection, and PET/CT images were acquired. Image quality was graded by consensus using the following scale: 1, good; 2, moderate; and 3, poor. The mean standardized uptake value (SUV(mean)) of the liver, gluteal muscle, and brain was assessed to evaluate the effects of ultrashort-acting insulin. RESULTS: The group administered ultrashort-acting insulin (n=52, blood glucose level: 243.7 ± 46.2 mg/dl) showed a significantly higher glucose level compared with the group not administered ultrashort-acting insulin (n=53, 177.1 ± 5.2 mg/dl). Nevertheless, the image quality of the group with ultrashort-acting insulin was not significantly different from that of the group without ultrashort-acting insulin (χ(2) -test, P=0.47). No significant differences were seen in SUV(mean) in the liver (P=0.13), gluteal muscle (P=0.71), and brain (P=0.16) between groups. CONCLUSION: Ultrashort-acting insulin can be used to improve the image quality of F-FDG PET/CT in uncontrolled DM patients without significant differences in SUV.
Subject(s)
Diabetes Mellitus/diagnostic imaging , Fluorodeoxyglucose F18 , Insulin/pharmacology , Multimodal Imaging/methods , Positron-Emission Tomography , Tomography, X-Ray Computed , Aged , Aged, 80 and over , Diabetes Mellitus/metabolism , Diabetes Mellitus/therapy , Female , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Insulin/administration & dosage , Male , Middle Aged , Time Factors , Tissue Distribution/drug effects , Treatment FailureABSTRACT
OBJECTIVE: The aim of this study was to document the subjective and objective findings of symptomatic late-onset sialadenitis after radioiodine therapy in patients with differentiated thyroid cancer. METHODS: Subjective symptoms related to sialadenitis and Tc-99m pertechnetate salivary gland scintigram findings were assessed in 118 patients (26 males, 92 females) both before and during the late phase (mean 338 days) after the administration of radioiodine. RESULTS: Twelve of the 118 patients (10.2 %) complained of symptomatic sialadenitis in the late phase without symptoms during the early phase (within 7 days of radioiodine administration). Significant associations were found between subjective symptoms and visual scintigram findings during the late phase (p = 0.023). Furthermore, uptake and excretion by both parotid glands were significantly affected by radioiodine therapy. CONCLUSIONS: Symptomatic late-onset sialadenitis occurred at an incidence of 10.2 %, and salivary gland function was affected in both parotids in most patients.
Subject(s)
Iodine Radioisotopes/therapeutic use , Radiation Injuries/epidemiology , Sialadenitis/epidemiology , Thyroid Neoplasms/epidemiology , Thyroid Neoplasms/radiotherapy , Adult , Aged , Comorbidity , Female , Humans , Incidence , Male , Middle Aged , Republic of Korea/epidemiology , Risk FactorsABSTRACT
PURPOSE: Bone metastasis is an important factor for the treatment and prognosis of breast cancer patients. Whole-body bone scintigraphy (WBBS) can evaluate skeletal metastases, and (18)F-FDG PET/CT seems to exhibit high specificity and accuracy in detecting bone metastases. However, there is a limitation of (18)F-FDG PET in assessing sclerotic bone metastases because some lesions may be undetectable. Recent studies showed that (18)F-fluoride PET/CT is more sensitive than WBBS in detecting bone metastases. This study aims to evaluate the usefulness of (18)F-fluoride PET/CT by comparing it with WBBS and (18)F-FDG PET/CT in breast cancer patients with osteosclerotic skeletal metastases. MATERIALS AND METHODS: Nine breast cancer patients with suspected bone metastases (9 females; mean age ± SD, 55.6 ± 10.0 years) underwent (99m)Tc-MDP WBBS, (18)F-FDG PET/CT and (18)F-fluoride PET/CT. Lesion-based analysis of five regions of the skeletons (skull, vertebral column, thoracic cage, pelvic bones and long bones of extremities) and patient-based analysis were performed. RESULTS: (18)F-fluoride PET/CT, (18)F-FDG PET/CT and WBBS detected 49, 20 and 25 true metastases, respectively. Sensitivity, specificity, positive predictive value and negative predictive value of (18)F-fluoride PET/CT were 94.2 %, 46.3 %, 57.7 % and 91.2 %, respectively. Most true metastatic lesions on (18)F-fluoride PET/CT had osteosclerotic change (45/49, 91.8 %), and only four lesions showed osteolytic change. Most lesions on (18)F-FDG PET/CT also demonstrated osteosclerotic change (17/20, 85.0 %) with three osteolytic lesions. All true metastatic lesions detected on WBBS and (18)F-FDG PET/CT were identified on (18)F-fluoride PET/CT. CONCLUSION: (18)F-fluoride PET/CT is superior to WBBS or (18)F-FDG PET/CT in detecting osteosclerotic metastatic lesions. (18)F-fluoride PET/CT might be useful in evaluating osteosclerotic metastases in breast cancer patients.
ABSTRACT
Malignant fibrous histiocytoma (MFH) is the most common soft tissue tumor which often occurs in the extremities and the retroperitoneum. Primary mediastinal MFH is rare; thus, findings on (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) of mediastinal MFH have not been reported yet. We report herein the case of a 64-year-old man who was presented with a superior mediastinal mass. The mass showed intense (18)F-FDG uptake with central metabolic defect on PET/CT. The maximum standardized uptake value was 17.4. After tumor removal via median sternotomy, an MFH of the storiform-pleomorphic type was diagnosed on histopathologic examination. We present the first report of (18)F-FDG PET/CT imaging of MFH in the superior mediastinum.
ABSTRACT
We report a case of incidental multiple focal uptakes of Tc-99m MDP in both the lungs without lung parenchymal abnormality. A 15-year-old girl who had no symptoms or history of pulmonary disorder was referred for Tc-99m MDP bone scintigraphy to evaluate temporomandibular joint disorders. Bone scintigraphy showed multiple focal uptakes in the chest. Single photon emission computed tomography/computed tomography scan performed on the same day showed that abnormal uptakes were located in both the lungs and no abnormalities in the corresponding pulmonary parenchymal sites. Abnormal uptakes resolved on bone scintigraphy after 7 days.
Subject(s)
Incidental Findings , Lung/diagnostic imaging , Lung/pathology , Technetium Tc 99m Medronate , Adolescent , Bone and Bones/diagnostic imaging , Female , Humans , Radionuclide Imaging , Whole Body ImagingABSTRACT
PURPOSE: We investigated the clinical significance of diffuse uptake in remaining thyroid after unilateral lobectomy for thyroid cancer. METHODS: A total of 144 thyroid cancer patients who underwent (18)F-FDG PET/CT after lobectomy were enrolled in the present study. The PET/CT images were evaluated for the presence of diffuse (18)F-FDG uptake with maximum SUV (SUVmax) >2.0 in the residual thyroid and placed into one of two groups: with diffuse uptake and without diffuse uptake group. Clinical, laboratory, and PET/CT parameters in both groups were compared. Correlations between SUVmax of thyroid and available parameters were analyzed. RESULTS: Forty-two of 144 patients (29.2%) had diffuse thyroid uptake (mean SUVmax: 3.2 ± 1.1). All patients with diffuse uptake and 96 (94.1%) without diffuse uptake were receiving thyroxine therapy (P = 0.09). Thyroid function tests showed that most patients were euthyroid status (78.6 vs. 85.3%, P = 0.36). TgAb levels were significantly higher in patients with diffuse uptake (338.0 ± 664.6 vs. 57.3 ± 46.4, P < 0.0001). Mean attenuation values in the diffuse uptake group were significantly lower (72.2 ± 15. vs. 97.0 ± 16.0, P < 0.0001). An inverse correlation was found between SUVmax and mean attenuation values of residual thyroid in all patients (r = -0.57, P < 0.0001) and subgroup with diffuse uptake (r = -0.31, P < 0.05). CONCLUSION: In this study, diffuse (18)F-FDG uptake in the residual thyroid after unilateral lobectomy was a relatively frequent finding and may be associated with chronic thyroiditis. This uptake is not influenced by thyroid status or thyroxine therapy. The (18)F-FDG uptake is inversely correlated with mean attenuation value of thyroid.
ABSTRACT
Although the double-stapling technique has been used as a safe procedure in gastroduodenostomy, creating anastomosis with a circular stapler on the linear stapler line can be vulnerable for anastomotic leakage and ischemia. Therefore, we tried to modify the double-stapling technique to avoid stapling on the staple line.
Subject(s)
Anastomosis, Surgical/methods , Gastroenterostomy/methods , Surgical Stapling/methods , Humans , Stomach Neoplasms/surgeryABSTRACT
Multiwalled carbon nanotubes (MWCNTs) are considered to be ideal multifunctional materials for biorelated applications, but there is still some controversy regarding their toxicity. In addition, the poor dispersibility of MWCNTs in either water or organic solvents has limited their practical applications. Therefore, obtaining a good dispersion is one of the key issues in their applications. In this study, MWCNTs were dispersed in an aqueous solution using silk fibroin without chemical modification. An optical analyzer, Turbiscan, was used to confirm the stability of the MWCNT aqueous dispersion. Transmission electron microscopy showed individual MWCNTs coated with silk fibroin molecules. Silk fibroin in the sol state can interact with nanotubes through hydrophobic interactions. Therefore, silk fibroin molecules coat the nanotubes, which allow their dispersion in water. Under basic conditions (pH 12.0), an aqueous dispersion of MWCNTs with silk fibroin was stable without sedimentation or gelation. However, the MWCNT/silk fibroin dispersion was unstable under acidic conditions (pH 4.0). In addition, the MWCNT dispersion showed reversible changes with variations in pH. Under acidic conditions, the MWCNTs settled due to conformation changes in the silk fibroin. However, the stability of the MWCNTs had recovered fully under basic conditions. It is believed that silk fibroin has sol-like behavior under basic conditions and gel-like behavior under acidic conditions. Ultraviolet circular dichroism was used to determine the conformation of the silk fibroin molecules with pH. Overall, the pH-sensitive properties of the carbon nanotubes dispersed with silk fibroin can lead to a new class of novel biomaterials for cancer detection and treatment.
Subject(s)
Fibroins/chemistry , Nanotubes, Carbon/chemistry , Animals , Bombyx/chemistry , Hydrogen-Ion Concentration , Particle Size , Solutions , Surface PropertiesABSTRACT
Electrically conducting polymeric membranes were prepared by incorporating multiwalled carbon nanotubes (MWCNTs) into bacterial cellulose pellicles produced by Gluconacetobacter xylinum. The MWCNTs were dispersed in a surfactant (cationic cetyl trimethylammonium bromide) solution, and cellulose pellicles were dipped into the solution for 6, 12, and 24 h. The surfactants were then extracted in pure water and dried. Electron microscopy showed that the individual MWCNTs were strongly adhered to the surface and the inside of the cellulose pellicle. The conductivity of the MWCNTs-incorporated cellulose pellicle, as measured by a four-probe at room temperature, was 1.4 x 10(-1) S/cm, based on the total cross-sectional area (approximately 9.6 wt % of MWCNTs). This suggests that the MWCNTs were incorporated uniformly and densely into the pellicles.