Chemically or surgically induced thyroid dysfunction altered gut microbiota in rat models.

Thyroid hormones are essential for the regulation of energy homeostasis and metabolic processes. However, the relationship between thyroid function and host gut microbial communities is not properly understood. To determine whether and how gut microbiota is associated with thyroid function, metagenomics analysis of the bacterial population in fecal samples of rat models of hyperthyroidism (induced by levothyroxine) and hypothyroidism (induced by propylthiouracil or thyroidectomy) was conducted through 16S rRNA gene sequencing. Our results revealed that all thyroid dysfunction models were definitely established and gut microbial composition varied according to different thyroid functional status. The relative abundance of Ruminococcus was significantly higher in the hyperthyroidism group (HE) vs both the normal and hypothyroidism groups (HO) while S24-7 was significantly higher in the HO group. The population of Prevotellaceae and Prevotella were significantly lower in the HO group vs the normal. Firmicutes and Oscillospira were significantly higher in the SHO (surgery-induced hypothyroidism) group, while Prevotellaceae and Prevotella showed lower abundance in the SHO group than the SHAM group. Present results suggest that thyroid functions may have the potential to influence the profile of gut microbiota and could be used as foundation to investigate interaction mechanism between thyroid and gut microbiome.

Ultrasonographic findings relating to lymph node metastasis in single micropapillary thyroid cancer.

BACKGROUND: In thyroid cancer, preoperative ultrasonography (US) is performed to detect the primary tumor and lymph node metastasis (LNM), which are related to prognosis. This study examined the relationships between specific US findings and LNM in micropapillary thyroid cancer (MPTC). METHODS: Data on 220 patients with solitary MPTC who underwent total thyroidectomy and neck dissection between 2008 and 2009 were evaluated retrospectively. We classified the US findings according to the nature, shape, echogenicity, extent, margin, and calcification of the primary tumor and evaluated the correlations between these findings and those of LNM. RESULTS: Hypoechogenicity (odds ratio = 2.331, P = 0.025) and marked hypoechogenicity (OR = 4.032, P = 0.016) of MPTC were risk factors for central LNM. All of the patients with lateral cervical LNM showed hypoechogenicity or marked hypoechogenicity. Hypoechogenicity (odds ratio = 5.349, P = 0.047) and other types of calcification (odds ratio = 2.495, P = 0.010) were significant risk factors for lateral cervical LNM. CONCLUSIONS: Specific sonographic findings (hypoechogenicity or marked hypoechogenicity, and calcification) suggest LNM.

Parathyroid-on-a-chip simulating parathyroid hormone secretion in response to calcium concentration.

The parathyroid gland is an endocrine organ that plays a crucial role in regulating calcium levels in blood serum through the secretion of parathyroid hormone (PTH). Hypoparathyroidism is a chronic disease that can occur due to parathyroid defects, but due to the difficulty of creating animal models of this disease or obtaining human normal parathyroid cells, the evaluation of parathyroid functionality for drug development is limited. Although parathyroid-like cells that secrete PTH have recently been reported, their functionality may be overestimated using traditional culture methods that lack in vivo similarities, particularly vascularization. To overcome these limitations, we obtained parathyroid organoids from tonsil-derived mesenchymal stem cells (TMSCs) and fabricated a parathyroid-on-a-chip, capable of simulating PTH secretion based on calcium concentration. This chip exhibited differences in PTH secretion according to calcium concentration and secreted PTH within the range of normal serum levels. In addition, branches of organoids, which are difficult to observe in animal models, were observed in this chip. This could serve as a guideline for successful engraftment in implantation therapies in the future.

Isolation of mesenchymal stromal cells (MSCs) from human adenoid tissue.

BACKGROUND: Mesenchymal stromal cells (MSCs) are multipotent progenitor cells that originally derived from bone marrow. Clinical use of bone marrow-derived MSC is difficult due to morbidity and low MSC abundance and isolation efficiency. Recently, MSCs have been isolated from various adult tissues. Here we report the isolation of adenoid tissue-derived MSCs (A-MSCs) and their characteristics. METHODS: We compared the surface markers, morphologies, and differentiation and proliferation capacities of previously established tonsil-derived MSCs (T-MSCs) and bone marrow-derived MSCs (BM-MSCs) with cells isolated from adenoid tissue. The immunophenotype of A-MSCs was investigated upon interferon (IFN)-γ stimulation. RESULTS: A-MSCs, T-MSCs, and BM-MSCs showed negative CD45, CD31 HLA-DR, CD34, CD14, CD19 and positive CD 90, CD44, CD73, CD105 expression. A-MSCs were fibroblast-like, spindle-shaped non-adherent cells, similar to T-MSCs and BM-MSCs. Adipogenesis was observed in A-MSCs by the formation of lipid droplets after Oil Red O staining. Osteogenesis was observed by the formation of the matrix mineralization in Alizarin Red staining. Chondrogenesis was observed by the accumulation of sulfated glycosaminoglycan-rich matrix in collagen type II staining. These data were similar to those of T-MSCs and BM-MSCs. Expression of marker genes (i.e., adipogenesis; lipoprotein lipase, proliferator-activator receptor-gamma, osteogenesis; osteocalcin, alkaline phasphatase, chondrogenesis; aggrecan, collagen type II α1) in A-MSCs were not different from those in T-MSCs and BM-MSCs. CONCLUSIONS: A-MSCs possess the characteristics of MSCs in terms of morphology, multipotent differentiation capacity, cell surface markers, and immunogeneity. Therefore, A-MSCs fulfill the definition of MSCs and represent an alternate source of MSCs.

Nodal status of central lymph nodes as a negative prognostic factor for papillary thyroid carcinoma.

BACKGROUND: The status of metastatic lymph nodes, including the size and extracapsular spread (ECS), in papillary thyroid cancer (PTC) has not been well established. This study evaluated the correlation between the specific status of central lymph node metastases (CLNM) and negative prognostic factors. METHODS: We reviewed 243 patients who underwent total thyroidectomy and neck dissection. The CLNM slides were reviewed and the relationship between the CLNM status and risk factors was analyzed. RESULTS: CLNM were found in 111 patients. ECS (+) was related to a large tumor, high number of CLNM, and large node (P < 0.05). Tumor size and number of CLNM were related to the ECS rate (OR = 3.861 and 2.491, respectively; P < 0.01) in a multivariate analysis. Large nodes (≥ 6 mm) were related to large tumor size, extrathyroidal extension, number of CLNM, and lateral cervical lymph node metastasis (LNM). Tumor size and LNM (OR = 4.519 and 7.811, respectively; P < 0.05) were related to large nodes in a multivariate analysis. CONCLUSIONS: ECS was related to node size, tumor size, and number of CLNM. Node size was related to tumor size and LNM. Thus, specific nodal status is a possible prognostic factor for PTC.

A Rat Model for Oral Mucositis Induced by a Single Administration of 5-Fluorouracil.

BACKGROUND/AIM: This study aimed to develop a reliable chemotherapy-induced oral mucositis (CIOM) rat model by intraperitoneally administering a single dosage of 5-fluorouracil (5-FU) combined with a chemical stimulus. MATERIALS AND METHODS: The 5-FU dosage for CIOM development was determined by the survival rate of rats administrated 160 mg/kg, 200 mg/kg, and 240 mg/kg of 5-FU. Thirty rats were assigned to normal control (NC) and three experimental groups: i) ulcer formation without 5-FU administration (PBS/U+), ii) 5-FU administration without ulcer formation (5-FU/U-), and iii) ulcer formation after 5-FU administration (5-FU/U+). White blood cell count and weight were measured at the day of 5-FU administration (D0), ulcer formation (D2), and two days after ulcer formation (D4). The oral mucosa for histologic evaluations was obtained two (D4) and five days (D7) after ulcer formation. RESULTS: The 5-FU dosage for CIOM development was 200 mg/kg. White blood cell count (WBC) counts and weight of rats were significantly lower in 5-FU/U- (WBC, p<0.001; weight, p=0.002) and 5-FU/U+ (WBC, p<0.001; weight, p<0.001) groups compared to those in the NC group at D4. The number of Ki-67 positive cells in the oral epithelium was lower in 5-FU/U+ group compared to that in NC (p<0.001) and PBS/U+ (p=0.047) groups at D7. CONCLUSION: Single administration of 200 mg/kg of 5-FU combined with a chemical stimulus can lead to an immune-suppressive status, failure of weight gain, and impairment of epithelium regeneration as observed in a CIOM rat model.

Restoration of Homeostasis in the Tracheal Mucosa After Thyroid Surgery in a Rat Model.

BACKGROUND/AIM: This study aimed to investigate the process of homeostatic restoration in the tracheal mucosa (TM) after thyroid surgery. MATERIALS AND METHODS: Fifty-four rats were divided into normal controls (NC) and three experimental groups: (i) flap elevation (FE), (ii) thyroid exposure (TE), and (iii) thyroid isthmusectomy (TI). Expression of mRNA and proteins of key factors regulating homeostasis were evaluated in the TM obtained 3, 7, and 21 days after thyroid surgery. RESULTS: Increased mRNA expression of transforming growth factor-ß1 (TGF-ß1), hypoxia-inducible factor-1α (HIF-1α), and matrix metalloproteinase-9 (MMP-9) were observed 21 days after thyroid surgery in all experimental groups compared to that of NC group. CONCLUSION: Thyroid surgery leads to an actual increase of TGF-ß1, HIF-1α, and MMP-9 expression in the TM. This increased expression of key regulators of homeostatic restoration in the TM lasts for a considerable period of time after surgery, especially if the extent of surgery increased.

Changes in the Laryngeal Mucosa After Thyroid Surgery: A Rat Model.

BACKGROUND/AIM: Thyroidectomy can cause various airway symptoms affecting the quality of life. We investigated the changes in extracellular matrix (ECM) composition and markers for inflammation and microcirculation of laryngeal mucosa. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were categorized into control and three surgical groups based on the extent of surgeries, 1) flap elevation (FE) group, 2) thyroid and trachea exposure (TE) group, and 3) thyroid isthmectomy (TI) group. We analyzed the expression of TGF-ß1, VEGFR-3, CD31, and MMP- 9 in relation to the inflammatory and microcirculatory changes in the lamina propria on postoperative days (PODs) 3, 7, and 21. ECM composition of hyaluronic acid (HA) and collagen in the subglottic area (SA) was also evaluated. RESULTS: All parameters increased in surgical groups at each postoperative phase except collagen deposition. On POD 3, TGF-ß1 expression and SA increased in relation to the surgical extent and decreased over time, but more than the control in all surgical groups on POD 21. Surgical groups had more HA and less collagen composition, causing a higher HA to collagen ratio in relation to the surgical extent. VEGFR-3 and CD31 expression increased with time at all postoperative phases according to the surgical extent. Expression of MMP-9 increased in TI groups compared to TE and FE groups on POD 7 and POD 21. CONCLUSION: This study demonstrated that thyroid surgery exposing the thyroid and trachea induces an increase in the SA with a higher HA and lesser collagen composition. Furthermore, the markers for acute inflammation and microcirculation with tissue remodeling increased in the laryngeal mucosa.

Clinical implications of bilateral lateral cervical lymph node metastasis in papillary thyroid cancer: a risk factor for lung metastasis.

BACKGROUND: Distant metastasis to the lung in papillary thyroid cancer (PTC) is rarely detected, but it is known to be an important prognostic factor associated with survival. We investigated risk factors for lung metastasis in PTC. MATERIALS AND METHODS: We performed a retrospective review of patients with PTC (n=977) who were treated from January 2006 to August 2009. Enrolled patients received radioablation therapy followed by a radioiodine whole body scan. Lung metastasis was screened out with whole body scan or positron emission tomography/computed tomography (PET/CT) and confirmed with chest CT. Age, gender, extrathyroidal extension, central lymph node metastasis, lateral lymph node metastasis, and bilateral lateral cervical lymph node metastasis (BLNM) were investigated to analyze the relationship with lung metastasis. RESULTS: In total, 949 patients were enrolled. The median age was 49 years (±13 years) with 829 women. Lung metastasis was found in 20 patients (2.1%). Patients were divided into three groups by tumor size (≤1 cm, 1-2 cm, >2 cm); the groups comprised 47.3%, 28.5%, and 24.1% of the patients, respectively. BLNM was identified in 4.4% (n=43). In a univariate analysis, male gender, old age, large tumor, extrathyroidal extension, lymph node metastasis, lateral lymph node metastasis, and BLNM were significantly related to lung metastasis (P<0.05). In a multivariate analysis, BLNM appeared to be the only significant risk factor for lung metastasis (P=0.026; odds ratio=10.219). CONCLUSIONS: BLNM may be a risk factor for lung metastasis. This indicates that careful examinations, including chest CT and positron emission tomography (PET), are recommended during the follow-up period when BLNM is suspected.

Effects of allergic rhinitis on the progression and recovery of acute otitis media in a mouse model.

OBJECTIVES: The objective of this study was to evaluate the effects of allergic rhinitis (AR) on the development, progression, and recovery of acute otitis media (OM) in an animal model and investigate the secondary effects of bacterial infection. METHODS: BALB/c mice were divided into four groups: AR + OM, AR, OM, and control groups. AR + OM and AR groups were sensitized with ovalbumin (OVA) and alum and then challenged intranasally with OVA. Phosphate-buffered saline (PBS) was administered to the OM and control groups the same number of times. After AR induction, OM was induced by surgical inoculation of non-typeable Haemophilus influenza (NTHi) into the middle ear (ME) cavity of the mice in the AR + OM and OM groups. PBS was injected into the bulla in the AR and control groups. Each group was subdivided into sets of six mice, one for each of the four time points (0, 2, 7, and 10 days post-bacterial inoculation), at which point the mice were euthanized and ME and nasal cavity mucosa were obtained and evaluated. The occurrence of OM and the ME mucosa thickness were evaluated and compared among the four groups. Tissue expression of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) in infected ME mucosa was assessed by immunohistochemical staining. We also investigated IgE, IL-4, and IL-5 in the nasal mucosa. RESULTS: Most of the ears showed OM on post-inoculation day 2 in both AR + OM and OM groups. In the AR + OM group, 58.3% of ears still had OM on post-inoculation day 10, while only 16.7% of the OM group had OM. The ME mucosa of all groups increased, and the AR + OM group exhibited the thickest mucosa. The OM group showed peak thickness on post-inoculation day 2 and then decreased, whereas the ME mucosa thickness of the AR + OM group continued to increase to day 7. In the OM group, the expression of IL-1ß, IL-6, and TNF-α in the ME also increased significantly, peaking on post-inoculation day 2, and then gradually decreased. In the AR + OM group, the expression of these proteins increased until day 7 and then decreased. The IgE and Th2 response (IL-4 and IL-5) cytokines were expressed at higher levels in the AR + OM and AR groups than in the OM and control groups. CONCLUSION: The inflammatory reaction to NTHi was more intense and lasted longer in the allergic group, which indicates that AR affects the progression and subsequent recovery of acute bacterial OM.

Ultrasound Echogenicity of Papillary Thyroid Cancer Is Affected by Tumor Growth Patterns and Tumor Fibrosis.

BACKGROUND/AIM: The association between preoperative ultrasound (US) echogenicity and histopathological characteristics of papillary thyroid cancer (PTC) has been rarely investigated is not well characterized. This study evaluated a relationship between the clinical characteristics of PTC, histopathological phenomena including tumor growth patterns (TGPs) and tumor fibrosis (TF), and US echogenicity. PATIENTS AND METHODS: In total, 170 patients with PTC (<2 cm) underwent total thyroidectomy with central neck dissection. Demographics, US echogenicity, tumor size, extra-thyroidal extension (ETE), lymph node metastasis (LNM) within the central and lateral neck, TGPs, and TF percentage were reviewed. RESULTS: Patients with TGP II (encapsulated growth with partial pericapsular extension) and III (infiltrative growth) were more frequently burdened by ETE and lateral neck LNM compared to patients with TGP I (encapsulated growth with a well-defined cystic or solid characteristic). Older age was significantly deterministic of TGP III, and male gender and higher TF percentage were independent risk factors for lateral neck LNM. TGP III and TF were independent determining factors for marked hypoechogenicity on US. CONCLUSION: PTC with TGP II and III and higher tumor fibrosis exhibited more aggressive clinicopathologic behaviors. TGP III and TF were determinants for marked hypoechogenicity.

Clinical implication of the number of central lymph node metastasis in papillary thyroid carcinoma: preliminary report.

BACKGROUND: Papillary thyroid cancer (PTC) metastasizes to central lymph node (CLN). CLN metastasis is associated with high risk of locoregional recurrence and distant metastasis. The significance of the number of metastatic CLN has not been addressed. This study was designed to evaluate the clinical implication of the number of metastatic CLN in PTC. METHODS: We reviewed the patients who underwent total thyroidectomy and CLN dissection with or without lateral neck dissection due to PTC, from March 2008 to June 2009. The relationships between the number of CLN and risk factors, including age, gender, tumor size, extrathyroidal extension, and lateral lymph node metastasis, were assessed. Patients were divided into three groups according to the number of CLN: group A = 0; group B = 1-2; and group C = ≥3. RESULTS: Of 258 patients enrolled in this study, 113 were in group A, 73 in group B, and 72 in group C. Extrathyroidal extension and lateral neck lymph node metastasis were related to increased rate of CLN metastasis (P < 0.05). Tumor size increased as the number of CLN increased; group C had the largest tumor size (P < 0.05). When evaluating the distribution of patients with extrathyroidal extension, group C had a significant odds ratio (4.213, P < 0.05). When evaluating the distribution of lateral neck lymph node metastasis, groups B and C had significant odds ratio (14.353, 75.403, respectively, P < 0.05). CONCLUSIONS: The number of CLN metastasis correlated with the negative prognostic factors, including tumor size, extrathyroidal extension, and lateral neck lymph node metastasis. This suggests that the number of CLN has prognostic implication.

Changes in Tracheal Respiratory Mucosa After Thyroidectomy: A Rat Model.

BACKGROUND/AIM: This study aimed to investigate changes in the tracheal mucosa after thyroidectomy, that can be a cause of post-thyroidectomy discomfort. MATERIALS AND METHODS: Forty rats were divided into normal controls and 3 surgical groups: (i) thyroid isthmectomy with cauterization, (ii) isthmectomy by a cold instrument without hemostasis, and (iii) sham (exposure of the trachea and thyroid gland without thyroidectomy by dissection through pretracheal fascia). Animals were euthanized at 1 and 4 weeks. Mucosal edema and glandular hyperplasia were measured. Mucin production and basal cell activities were evaluated by mucin 5AC (MUC5AC) and keratin 5 (KRT5) using immunofluorescence staining. RESULTS: Larger mucosal areas were observed in all surgical groups at 1 and 4 weeks. More submucosal glandular hyperplasia was noted in the group with isthmectomy without hemostasis. MUC5AC and KRT5 expressions were significantly higher in the surgical groups. CONCLUSION: The tracheal mucosa may change after surgery, which could explain postoperative discomfort after thyroidectomy.

Prediction of anterior commissure exposure of vocal folds prior to laryngeal microscopic surgery: Parameters reflecting occipito-atlanto-axial complex extension capacity.

OBJECTIVE: The purpose of this prospective study was to identify preoperative predictors of unstable exposure of vocal folds with focus on the anterior commissure (AC) prior to Laryngeal Microscopic Surgery. METHODS AND MATERIALS: Patients were classified into four groups based on the degree of AC exposure during Laryngeal Microscopic Surgery, and for the analysis, these groups were subdivided into unstable exposure and stable exposure subgroups depending on whether external manipulation was required to achieve AC exposure. Correlation of the degree of AC exposure with demographics, physical measurements, and anatomical measurements taken using landmarks in simple radiograph were evaluated. Receiver operating characteristic curve analysis was used to determine optimal cutoff values to predict unstable AC exposure. RESULTS: Fifty-nine patients were included in the analyses. Thyroid-mandible angle (TMA) in the extended position, thyroid-mental distance (TMD) ratio, and TMA difference in the neutral and extended positions were significantly correlated with the degree of AC exposure. However, only a TMD ratio of <1.25 reliably predicted unstable AC exposure. CONCLUSIONS: TMD ratio of <1.25 reliably predicted unstable AC exposure. If there is no increase of the distance between the thyroid notch and the mental prominence (TMD) more than 25% on neck extension, the probability of getting stable exposure of the anterior commissure is low.

The Clinical Manifestations and Chest Computed Tomography Findings of Coronavirus Disease 2019 (COVID-19) Patients in China: A Proportion Meta-Analysis.

OBJECTIVES: The objectives of this study were to identify the clinical features and chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) patients and to compare the characteristics of patients diagnosed in Wuhan and in other areas of China by integrating the findings reported in previous studies. METHODS: We conducted a proportion meta-analysis to integrate the results of previous studies identified in online databases, and subsequently compared the overlapping of 95% confidence intervals (CIs) between locations of diagnosis. The heterogeneity of the results of the included studies was also demonstrated. RESULTS: Nine studies with level IV evidence were considered to be eligible for the meta-analysis, and a comparative analysis was only possible between patients diagnosed in Wuhan and outside of Wuhan in China. Fever (84.8%; 95% CI, 78.5% to 90.1%) was identified as the most common clinical manifestation in all COVID-19 patients, and signs of respiratory infection were also frequently present in these patients. When comparing the clinical features according to the location of diagnosis, fever and dyspnea were less frequent in patients diagnosed outside of Wuhan (fever: 78.1%; 95% CI, 73.2% to 82.7%; dyspnea: 3.80%; 95% CI, 0.13% to 12.22%) than in patients diagnosed in Wuhan (fever: 91.7%; 95% CI, 88.0% to 94.8%; dyspnea: 21.1%; 95% CI, 13.2% to 30.3%). The chest CT findings exhibited no significant differences between the groups. CONCLUSION: Fever was found to be the most common symptom in COVID-19, and respiratory infection signs were also commonly present. Fever and dyspnea were less frequently observed in the patients diagnosed outside of Wuhan, which should be considered in COVID-19 screening programs. These results may be attributable to the earlier diagnosis of the disease and the younger age of patients outside of Wuhan although further analysis is needed. The role of chest CT in COVID-19 diagnosis is inconclusive based on this study.

Effects of Amniotic Membrane Extract on the Hyperplastic Response of the Middle Ear Mucosa in a Bacterially-Induced Otitis Media Rat Model: A Preliminary Study.

OBJECTIVES: Human amniotic membrane extract (AME) is known to contain numerous bioactive factors and anti-inflammatory substances. However, the anti-inflammatory effects of AME on the middle ear (ME) mucosa are unclear. This study assessed the effects of AME on the growth of the ME mucosa in response to bacterially-induced otitis media (OM). METHODS: OM was induced by inoculating nontypeable Haemophilus influenzae (NTHi) into the ME cavity of rats. ME mucosal explants were cultured in AME concentrations of 0, 5, 10, or 50 µg/mL. The area of explant outgrowth was measured in culture and analyzed at 1, 3, 5, and 7 days after explantation. The expression of Ki-67, mucin 5AC (MUC5AC), tumor necrosis factor-α (TNF-α), and interleukin-10 (IL-10) in the explants was also evaluated using quantitative polymerase chain reaction (PCR) and immunocytochemistry (ICC). RESULTS: The NTHi-induced ME mucosa growth increased gradually over the 7-day culture period in all explants at different AME concentrations. There was a trend for mucosal growth inhibition at higher concentrations of AME, although the growth was not significantly different among the groups until day 5. The ME mucosal explants treated with the 50 µg/mL concentration of AME showed significantly suppressed growth on postexplantation day 7 compared with other explants on the same day. PCR and ICC staining revealed that the expression of Ki-67, MUC5AC, TNF-α, and IL-10 further decreased in the explants with higher concentrations of AME than in those with lower concentrations of AME. CONCLUSION: Our results showed that higher concentrations of AME reduced the mucosal proliferative response in bacterial OM in rats. These findings provide evidence that AME has an influence on the inflammatory and proliferative responses to NTHi infection in ME mucosa.

A New Therapeutic Approach Using a Calcilytic (AXT914) for Postsurgical Hypoparathyroidism in Female Rats.

Postsurgical hypoparathyroidism is the most common complication of thyroid surgery. Conventional therapy with high-dose calcium and vitamin D can correct hypocalcemia but can increase the risk of hypercalciuria, renal stones, or ectopic calcification. The aim of the present study was to investigate the efficacy of a calcium-sensing receptor antagonist, also called a calcilytic (AXT914), in rat models of postsurgical hypoparathyroidism. Two postsurgical hypoparathyroidism rat models were made by hemi-parathyroidectomy or total parathyroidectomy with autotransplantation in 10-week-old female Wistar rats. AXT914 or vehicle was administered orally for 2 to 3 weeks. Serum PTH, calcium, and phosphorus levels, and the urinary excretion of calcium were measured. Autotransplanted parathyroid tissues were collected and examined histologically. In the hemi-parathyroidectomy model, the oral administration of the calcilytic AXT914 (5 and 10 mg/kg) for 2 weeks increased serum PTH and calcium levels and decreased serum phosphorus levels and urinary calcium excretion. In the total parathyroidectomy with autotransplantation model, the oral administration of AXT914 (10 mg/kg) for 3 weeks increased serum PTH and calcium levels and decreased serum phosphorus levels. The serum PTH and calcium levels increased by AXT914 were maintained for 1 week, even after discontinuation of the drug. In conclusion, AXT914 increased PTH secretion in rat models of postsurgical hypoparathyroidism, thereby correcting abnormal calcium and phosphorus homeostasis. Furthermore, AXT914 improved the functional recovery of autotransplanted parathyroid tissues.

A comparison of single-dose and multiple divided daily-dose oral steroids for sudden sensorineural hearing loss.

INTRODUCTION: Glucocorticoids are considered the first-line therapy for sudden sensorineural hearing loss. But there is currently no consensus on administering them as a single dose versus multiple divided daily doses. OBJECTIVE: We aim to evaluate the treatment outcome of sudden sensorineural hearing loss between a single-dose and multiple divided daily doses of steroid treatment. METHODS: A total of 94 patients who were diagnosed and treated for sudden sensorineural hearing loss and followed up for more than three months were reviewed retrospectively. Patients were divided into single-dose and multiple divided-dose groups, based on their medication regimens. Hearing thresholds were repeatedly measured: on the initial visit and 1 week, 1 month, and 3 months after the initial treatment. Treatment outcomes were analyzed by comparing hearing recovery rates and post-treatment audiometric changes. RESULTS: The hearing threshold was significantly reduced at three months post-treatment in both groups. The hearing recovery rate of the single-dose group was significantly higher than that of the multiple divided-dose groups. Audiometric changes showed no statistical difference either in pure tone threshold or speech discrimination. CONCLUSION: When oral steroids are indicated for sudden sensorineural hearing loss, both a single dose and multiple divided doses can be effective for treatment and have comparable results. However, the single-dose regimen seems to be more efficacious than the divided-dose regimen.

Expression of surfactant Protein-A in the Haemophilus influenzae-induced otitis media in a rat model.

The objective of this study was to investigate the expression and the role of surfactant protein A (SP-A) in the middle ear (ME) mucosa in response to bacterial infection in a rat model. Otitis media (OM) was induced by surgical inoculation of non-typeable Haemophilus influenza (NTHi) into the ME cavity of Sprague-Dawley rats. The rats were divided into an NTHi-induced OM group and a phosphate-buffered saline-injected control group. The NTHi-induced OM and control groups were subdivided into sets of 6 rats, one for each of the 6 time points (0, 1, 2, 4, 7, and 14 days post-inoculation), at which point the rats were euthanized after inoculation. The concentrations of SP-A in the ME effusion were determined by an enzyme-linked immunosorbent assay (ELISA). Tissue expression of SP-A, interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in infected ME mucosa was assessed by immunohistochemical staining. For mRNA expression quantification, RNA was extracted from the ME mucosa and SP-A expression was monitored and compared between the control and OM groups using quantitative polymerase chain reaction (PCR). Expression of IL-1ß, IL-6, and TNF-α in the ME mucosa was also evaluated. SP-A expression was evaluated in the effusion of pediatric OM patients (70 ears) who received ventilation-tube insertion by ELISA. SP-A was detected in normal rat ME mucosa before bacterial inoculation. SP-A expression was up-regulated in the NTHi-induced OM group (p = 0.046). Immunohistochemical staining revealed increased SP-A expression on post-inoculation day 1, 2, and 4 in the OM group. Expression of proinflammatory cytokines (IL-1ß, IL-6, and TNF-α) in the ME also increased significantly on post-inoculation day 1, 2, and 4 in the OM group. It correlated with changes in SP-A expression. Expression of SP-A was also identified in the ME effusion of humans. SP-A exists in the ME of the rat and was up-regulated in the ME of NTHi-induced OM. Expression of IL-1ß, IL-6, and TNF-α was increased in the ME of the bacteria-induced OM in the rat model. The results suggest that SP-A may play a significant role in the early phase of OM induction and subsequent recovery from it.

Effects of excessive fibrin deposit and polylactide adhesion barrier on wound healing in thyroidectomy murine wound model.

BACKGROUND: We hypothesize that excessive fibrin formation and inflammation induced by antiadhesive material, SurgiWrap (SW), would have an adverse effect on wound healing. It was evaluated by a thyroidectomy murine wound model. METHODS: Excessive fibrin formation was induced by isthmectomy without hemostasis. Rats were allocated into isthmectomy with SurgiWrap (I+SW+), I+SW-, I-SW+, I-SW-, and isthmectomy after electrocautery for hemostasis (I+C+SW-). The SWs were placed on the superficial and visceral layers for gross and microscopic evaluation. RESULTS: Microscopic examination showed collagen deposition occurred in the I-SW- sham group and at a higher level in I+C+SW-. The collagen deposition decreased in groups without SW with time but increased in groups with SW. Use of SW produced more inflammation and more collagen deposition. The I+SW + group developed the largest area of collagen deposition at 4 weeks and more collagen deposition than the I-SW + group. CONCLUSION: The SW induced more collagen deposition increasing with time. The collagen deposition produced by SW was worsened by excessive fibrin formation and inflammation.