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91.
OBJECTIVE: Vasopressin (AVP) is reported to be an important factor for regulating cortisol secretion in patients with Cushing's syndrome due to ACTH-independent macronodular adrenocortical hyperplasia (AIMAH). Recently, there have been several case reports of subclinical Cushing's syndrome due to AIMAH, in which the pathophysiological role of AVP has been unknown. The aim was to conduct an extensive investigation of AVP in the autonomous secretion of cortisol in subclinical Cushing's syndrome due to AIMAH. PATIENTS AND MEASUREMENTS: Five cases of AIMAH with subclinical Cushing's syndrome underwent prospective study including physical examination, imaging (MRI, CT and 131I-adosterol scintigraphy) and endocrinological evaluation that comprised basal plasma cortisol levels and urinary excretions of steroid metabolites, a dexamethasone suppression test and an AVP stimulation test. In case 1, left adrenalectomy was performed and the pathological diagnosis of AIMAH was established. An in vitro experiment using the cultured AIMAH adrenal cells was conducted to investigate cortisol secretion and expression of the V1-AVP receptor, mRNA by RT-PCR. RESULTS: All five cases were discovered incidentally to have bilateral adrenal nodules. Imaging by MRI and CT revealed large multinodular lesions in both adrenal glands, which showed positive uptake on 131I-adosterol scintigraphy. Although the basal values of plasma cortisol and urinary excretions of steroid metabolites were within normal limits, autonomous secretion of cortisol was assumed to occur because of lack of suppression during dexamethasone suppression. The five patients had no overt signs of Cushing's syndrome, and they were therefore diagnosed with subclinical Cushing's syndrome due to AIMAH. In all five patients, AVP stimulated cortisol secretion in vivo, whereas desmopressin acetate failed to affect cortisol secretion. In case 1, AVP stimulated cortisol secretion from cultured AIMAH adrenal cells, but this secretion had no relationship with cAMP production. In addition, over-expression of V1-AVP receptor mRNA in AIMAH tissue was determined by RT-PCR. CONCLUSION: Patients with subclinical Cushing's syndrome due to AIMAH commonly exhibit cortisol responsiveness to AVP, and this is probably mediated through activation of overexpressed V1-AVP receptors.  相似文献   
92.

Objective

This study aimed to examine the association between lifestyle-related disorders and visceral fat mass, and to estimate an appropriate cutoff value for visceral fat mass that correlated with body mass index (BMI) and waist circumference (WC).

Methods

This cross-sectional study was conducted between July 2012 and August 2013 at Bange Kosei General Hospital, in Fukushima, Japan. All study participants were adult males who had completed voluntary medical check-ups that included estimation of visceral fat mass by bioelectrical impedance analysis (BIA). Participants were without past histories of atherosclerotic complications or were not currently taking medications for lifestyle-related disorders. Multivariate analysis was performed to estimate the association between lifestyle-related disorders and quartiles of visceral fat mass.

Results

Of 536 total respondents, 442 were included in the analysis. Mean participant age was 56 years, and mean values of BMI, WC, and visceral fat mass were 24.1 kg/m2, 85.9 cm, and 2.1 kg, respectively. Visceral fat mass ≥1.8 kg was positively associated with an increased prevalence of dyslipidemia, elevated blood pressure, and impaired glucose tolerance. Cutoff values that correlated with visceral fat mass (≥1.8 kg) were 85.3 cm for WC and 23.25 kg/m2 for BMI.

Conclusion

Visceral fat mass ≥1.8 kg was positively associated with lifestyle-related disorders and closely related to WC and BMI cutoff values used to diagnose obesity. BIA may be a useful method for assessing visceral fat mass, and these findings provide important evidence for the use of BIA in the early detection of central obesity for preventing lifestyle-related disorders.  相似文献   
93.
94.

Background

l-glutamate is a major excitatory neurotransmitter in the mammalian brain. Glutamate receptors have been reported in the rat adrenal cortex and in human aldosterone-producing adenomas (APA). However, details regarding the expression levels and functions of these receptors in human adrenocortical tissues remain unknown.

Methods

The mRNA levels of glutamate receptors were evaluated by qPCR in: 12 normal adrenal cortex (NAC), 11 APA, and 12 cortisol-producing adenoma (CPA) tissues. Protein localization was evaluated by immunohistochemistry for 15 NAC, 5 idiopathic hyperaldosteronism cases, 15 APA and 15 CPA. H295R cells were treated with angiotensin-II or forskolin alone or combined with the GRM2/3 agonist LY354740.

Results

The level of GRM3 mRNA was higher in APA than in CPA (P = 0.0086) or NAC (P = 0.0022). GRM1, IGLUR2, and IGLUR3 were also detected in adrenocortical tissues. When added to angiotensin-II/forskolin treatments, LY354740 decreased aldosterone and cortisol production in H295R cells.

Conclusions

GRM3 is considered to regulate steroidogenesis in adrenocortical tissues.  相似文献   
95.
Objectives

This study aimed to determine the factors associated with long-term quality of life of oral cancer survivors.

Materials and methods

A total of 508 survivors were assessed using the performance status scale for head and neck (PSS-HN), which comprises Eating in Public (E-Public), Normalcy of Diet (N-Diet), and Understandability of Speech (U-Speech). Stepwise multiple linear regression analysis was performed.

Results

The median time between the end of treatment and participating in the survey was 38 months (range, 6–250). Overall, 57–60% of survivors achieved full performance (100 score) of each PSS-HN score, whereas 15% had moderate or severe impairment (≤ 50 score) in E-Public and N-Diet, and 4% had impairment in U-Speech. These three scores deteriorated with increasing T-stage. Age, soft tissue reconstruction, trismus, and missing occlusal contacts on the contralateral side were significantly associated with E-Public and N-Diet. Neck dissection, hard tissue reconstruction, and missing occlusal contacts bilaterally were associated with U-Speech score.

Conclusion

Older age, T4 tumor, and soft tissue reconstruction were predictors of low E-Public and N-Diet performance scores. Increasing mouth opening and maintaining optimal occlusal contacts on the contralateral side may be effective ways to improve N-Diet and E-Public performance. Maintaining optimal occlusal contacts bilaterally may be effective for improving speech performance.

Clinical relevance

Oral health care to increase optimal occlusal contacts and rehabilitation of trismus may be promising factors to improve the functional performance of oral cancer survivors.

  相似文献   
96.
Bone scintigraphy (BS) of disseminated skeletal metastasis is sometimes misinterpreted as normal. The use of computer-assisted diagnosis (CAD) may resolve this problem. We investigated the performance of a CAD system, BONENAVI, in the diagnosis of disseminated skeletal metastasis. Cases of disseminated skeletal metastasis were selected from a BS log. These patients’ BSs were analyzed by BONENAVI to obtain an artificial neural network (ANN) and bone scan index (BSI). Clinical features (type of primary cancer, CT type, and BS type) were compared with the BONENAVI (ANN and BSI) results. The BS findings (diffuse increased axial skeleton uptake, inhomogeneity of uptake, proximal extremity contrast, and degree of renal uptake) and ANN or BSI were evaluated. Then, negative ANN patients were presented. Fifty-four patients were diagnosed as having disseminated skeletal metastasis. Regarding the primary cancers, 12 had prostate cancer, 16 gastric cancers, 16 breast cancers, and 10 miscellaneous cancers. Total sensitivity of ANN (≥ 0.5) was 76% (41/54). ANN values correlated with the BS type among clinical features. Diffuse increased axial skeleton uptake was mostly correlated with ANN of the BS findings. The BONENAVI CAD system was partially helpful in diagnosing disseminated skeletal metastasis, but the sensitivity of BONENAVI was not sufficient and underestimated the disseminated skeletal metastasis. Further improvement of this CAD system is necessary to improve the detectability of disseminated skeletal metastasis.  相似文献   
97.
98.
The purpose of this study was to report the outcomes of high-dose-rate (HDR) brachytherapy and hypofractionated external beam radiotherapy (EBRT) combined with long-term androgen deprivation therapy (ADT) for National Comprehensive Cancer Network (NCCN) criteria-defined high-risk (HR) and very high-risk (VHR) prostate cancer. Data from 178 HR (n = 96, 54%) and VHR (n = 82, 46%) prostate cancer patients who underwent 192Ir-HDR brachytherapy and hypofractionated EBRT with long-term ADT between 2003 and 2008 were retrospectively analyzed. The mean dose to 90% of the planning target volume was 6.3 Gy/fraction of HDR brachytherapy. After five fractions of HDR treatment, EBRT with 10 fractions of 3 Gy was administered. All patients initially underwent ≥6 months of neoadjuvant ADT, and adjuvant ADT was continued for 36 months after EBRT. The median follow-up was 61 months (range, 25–94 months) from the start of radiotherapy. The 5-year biochemical non-evidence of disease, freedom from clinical failure and overall survival rates were 90.6% (HR, 97.8%; VHR, 81.9%), 95.2% (HR, 97.7%; VHR, 92.1%), and 96.9% (HR, 100%; VHR, 93.3%), respectively. The highest Radiation Therapy Oncology Group-defined late genitourinary toxicities were Grade 2 in 7.3% of patients and Grade 3 in 9.6%. The highest late gastrointestinal toxicities were Grade 2 in 2.8% of patients and Grade 3 in 0%. Although the 5-year outcome of this tri-modality approach seems favorable, further follow-up is necessary to validate clinical and survival advantages of this intensive approach compared with the standard EBRT approach.  相似文献   
99.
The field of polymer-based membrane engineering has expanded since we first demonstrated the reaction of N-hydroxysuccinimide ester-terminated polymers with cells and tissues almost two decades ago. One remaining obstacle, especially for conjugation of polymers to cells, has been that exquisite control over polymer structure and functionality has not been used to influence the behavior of cells. Herein, we describe a multifunctional atom transfer radical polymerization initiator and its use to synthesize water-soluble polymers that are modified with bisphosphonate side chains and then covalently bound to the surface of live cells. The polymers contained between 1.7 and 3.1 bisphosphonates per chain and were shown to bind to hydroxyapatite crystals with kinetics similar to free bisphosphonate binding. We engineered the membranes of both HL-60 cells and mesenchymal stem cells in order to impart polymer-guided bone adhesion properties on the cells. Covalent coupling of the polymer to the non-adherent HL-60 cell line or mesenchymal stem cells was non-toxic by proliferation assays and enhanced the binding of these cells to bone.  相似文献   
100.
Although most fish have no enamel layer in their teeth, those belonging to Lepisosteus (gars), an extant actinopterygian fish genus, do and so can be used to study amelogenesis. In order to examine the collar enamel matrix in gar teeth, we subjected gar teeth to light and electron microscopic immunohistochemical examinations using an antibody against bovine amelogenin (27?kDa) and antiserum against porcine amelogenin (25?kDa), as well as region-specific antibodies and antiserum against the C-terminus and middle region, and N-terminus of porcine amelogenin, respectively. The enamel matrix exhibited intense immunoreactivity to the anti-bovine amelogenin antibody and the anti-porcine amelogenin antiserum in addition to the C-terminal and middle region-specific antibodies, but not to the N-terminal-specific antiserum. These results suggest that the collar enamel matrix of gar teeth contains amelogenin-like proteins and that these proteins possess domains that closely resemble the C-terminal and middle regions of porcine amelogenin. Western blot analyses of the tooth germs of Lepisosteus were also performed. As a result, protein bands with molecular weights of 78?kDa and 65?kDa were clearly stained by the anti-bovine amelogenin antibody as well as the antiserum against porcine amelogenin and the middle-region-specific antibody. It is likely that the amelogenin-like proteins present in Lepisosteus do not correspond to the amelogenins found in mammals, although they do possess domains that are shared with mammalian amelogenins.  相似文献   
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