A Case of Insulinoma with Hyperprocalcitoninemia and Hypercalcitoninemia Showing Coexpression of Insulin and Calcitonin in Its Tumor Cells

Neuroendocrine neoplasms can produce multiple hormones that are released into the bloodstream, causing symptoms that vary depending on the type and quantity of hormones involved. We herein report a 63-year-old asymptomatic patient with pancreatic insulinoma who showed marked elevations in circulating calcitonin and procalcitonin levels that returned to normal following surgery. Immunohistochemical analyses confirmed the co-staining of calcitonin and insulin immunoreactivity in the tumor cells, suggesting a calcitonin-producing insulinoma. This insulinoma released calcitonin and a considerable amount of its precursor peptide, procalcitonin, resulting in both hyperprocalcitoninemia and hypercalcitoninemia.

Glucose control in the early phase of hospitalization is associated with severe prognosis in coronavirus disease 2019 (COVID-19) patients with diabetes in Japan

We investigated the association of glycemic control in the early phase of hospitalization with the prognosis of COVID-19 in patients with diabetes. We analyzed the relationship between various clinical indices, including preprandial blood glucose levels measured by self-monitoring devices in the early phase after admission, and severe prognosis in 189 patients with complicated diabetes who were admitted to our hospital between February 22, 2020 and June 20, 2021. Enrolled patients had a median age of 72 years, median body mass index of 24.7, median HbA1c of 7.1%, and median mean preprandial capillary glucose (PPCG) of 179.1 mg/dL. Sixty-six patients progressed to severe disease, and the mean PPCG in severe cases was significantly higher than that in non-severe cases, 195.2 vs 167.8 mg/dL (p = 0.005). Analysis of the receiver operating characteristic curve showed that 179 mg/dL was the cut-off value, and the risk of severity was significantly higher in patients with a mean PPCG of 180 mg/dL or higher (odds ratio (OR) 3.210, p = 0.017) in multiple regression analysis. In this study, we found that the risk of severe COVID-19 increased in patients with a high mean PPCG in the early phase of hospitalization, suggesting that good glucose control in the early phase of COVID-19 with diabetes may be effective in preventing disease severity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-023-00656-8.

A case of IgG4-related hypophysitis maintained remission of diabetes insipidus for over 3 months after completion of steroid treatment

Summary

IgG4-related disease is a multiorgan disorder in which nodules and hypertrophic lesions are observed simultaneously, or separately, in areas including the pancreas, liver, lungs, salivary glands, thyroid glands, and pituitary glands. IgG4-related hypophysis is one of several IgG4-related diseases and is characterized by pituitary gland and pituitary stalk thickening, various degrees of hypopituitarism, and increased serum IgG4 levels. Steroid therapy is effective for patients with IgG4-related hypophysis, but the reported effectiveness of steroid therapy for restoring pituitary function differs between studies. Following an episode of autoimmune pancreatitis 10 years prior, enlargement of the pituitary gland and stalk along with panhypopituitarism and polyuria developed in a 73-year-old male. A high serum IgG4 level and biopsy of the submandibular gland showing infiltration of IgG4-positive plasma cells led to a clinical diagnosis of IgG4-related hypophysitis. Prednisolone treatment reduced the swelling of the pituitary gland and stalk and improved anterior pituitary function. Although arginine vasopressin secretion remained insufficient, polyuria was relieved and kept in remission even after prednisolone treatment was completed. This is the first reported case in which prednisolone was able to maintain both normal anterior pituitary function and remission of polyuria caused by IgG4-related hypophysitis. IgG4-related hypophysitis has previously been associated with a relapse of symptoms during treatment. However, the patient reported in this case study remained in remission for over 3 months after completion of steroid treatment and should be monitored closely for changes in pituitary function.

Learning points

Steroid therapy is the first-line therapy for pituitary dysfunction and pituitary stalk swelling in IgG4-related hypophysitis. In this case, although posterior pituitary function remained insufficient, polyuria was relieved and kept in remission for over 3 months even after prednisolone treatment was completed. IgG4-related hypophysitis has been associated with the relapse of symptoms during steroid tapering, and changes in pituitary function and symptoms should be monitored closely. When we encounter cases of adrenal insufficiency and polyuria during observation of autoimmune pancreatitis or other IgG4-related disease, we should consider the possibility of IgG4-related hypophysitis in mind.

Gastrointestinal symptoms in 609 Japanese patients with COVID-19: a single-center retrospective study

BACKGROUND

GI symptoms are common in acute COVID-19 patients. This study aimed to characterize the GI symptoms occurring in Japanese COVID-19 patients.

METHODS

This retrospective single-center cohort study included 751 hospitalized acute COVID-19 patients. The primary outcomes were the frequency and severity of GI symptoms. The secondary outcomes included the association between COVID-19 severity and GI symptoms and the timing of GI symptom onset.

RESULTS

After exclusion, the data of 609 patients were analyzed. The median age was 62 years, and 55% were male. The median time from initial symptom onset to admission was five days. On admission, 92% of the patients had fever, 35.1% had fatigue, 75% had respiratory symptoms, and 75% had pneumonia. The sample included patients with mild (19%), moderate (59%), and severe COVID-19 (22%). A total of 218 patients (36%) had GI symptoms, of which 93% were classified as grade 1/2; 170 patients had both respiratory and GI symptoms. Diarrhea was the most frequent GI symptom, occurring in 170 patients, followed by anorexia in 73 patients and nausea/vomiting in 36 patients, and abdominal pain in 8 patients. There was no significant relationship between COVID-19 severity and GI symptoms. Among COVID-19 patients with both GI and respiratory symptoms, 48% had respiratory symptoms preceding GI symptoms, 25% had GI symptoms preceding respiratory symptoms and 27% had a simultaneous onset of respiratory and GI symptoms.

CONCLUSION

Thirty-six percent of the Japanese COVID-19 patients had GI symptoms; diarrhea was the most frequent GI symptom but did not predict severe COVID-19.

Obesity, glucose intolerance, advanced age, and lymphocytopenia are independent risk factors for oxygen requirement in Japanese patients with Coronavirus disease 2019 (COVID-19)

At the current time of rising demand for hospital beds, it is important to triage COVID-19 patients according to the treatment needed during hospitalization. The need for oxygen therapy is an important factor determining hospital admission of these patients. Our retrospective study was designed to identify risk factors associated with the progression to oxygen requirement in COVID-19 patients. A total of 133 patients with laboratory-confirmed COVID-19 were admitted to our hospital from February 22, 2020, to August 23. After excluding asymptomatic, non-Japanese, pediatric, pregnant patients and also those who needed oxygen immediately at admission, data of the remaining 84 patients were analyzed. The patients were separated into those who required oxygen after admission and those who did not, and their characteristics were compared. Age, body mass index (BMI), lymphocyte count, C-reactive protein (CRP), lactate dehydrogenase, estimated glomerular filtration rate, glucose intolerance, hypertension, and dyslipidemia were significantly different between the two groups. Multivariate analysis identified four significant and independent risk factors of oxygen requirement, including advanced age, obesity, glucose intolerance and lymphocytopenia. Dividing the patients into subgroups according to the number of these risk factors found in each patient indicated that the need for oxygen increased with higher number of these risk factors in the same individual. Our results suggest that the presence of higher number of these risk factors in COVID-19 patients is associated with future oxygen requirement and that this index can be potentially useful in triaging COVID-19 patients staying home in the context of need for hospitalization.

Seroprevalence of SARS-CoV-2 antibodies among 925 staff members in an urban hospital accepting COVID-19 patients in Osaka prefecture, Japan: A cross-sectional study

The subclinical severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rate in hospitals during the pandemic remains unclear. To evaluate the effectiveness of our hospital's current nosocomial infection control measures, we conducted a serological survey of anti-SARS-CoV-2 antibodies (immunoglobulin [Ig] G) among the staff of our hospital, which is treating coronavirus disease 2019 (COVID-19) patients.The study design was cross-sectional. We measured anti-SARS-CoV-2 IgG in the participants using a laboratory-based quantitative test (Abbott immunoassay), which has a sensitivity and specificity of 100% and 99.6%, respectively. To investigate the factors associated with seropositivity, we also obtained some information from the participants with an anonymous questionnaire. We invited 1133 staff members in our hospital, and 925 (82%) participated. The mean age of the participants was 40.0 ± 11.8 years, and most were women (80.0%). According to job title, there were 149 medical doctors or dentists (16.0%), 489 nurses (52.9%), 140 medical technologists (14.2%), 49 healthcare providers (5.3%), and 98 administrative staff (10.5%). The overall prevalence of seropositivity for anti-SARS-CoV-2 IgG was 0.43% (4/925), which was similar to the control seroprevalence of 0.54% (16/2970) in the general population in Osaka during the same period according to a government survey conducted with the same assay. Seropositive rates did not significantly differ according to job title, exposure to suspected or confirmed COVID-19 patients, or any other investigated factors.The subclinical SARS-CoV-2 infection rate in our hospital was not higher than that in the general population under our nosocomial infection control measures.

Prader-Willi Syndrome with Slowly Progressive Insulin-dependent Diabetes Mellitus

We report the case of a 52-year-old woman with Prader-Willi syndrome (PWS) and diabetes. Her diabetes was managed with sulfonylurea followed by premixed insulin; however, her glycemic control gradually worsened and became unstable. Her urine and blood C-peptide levels were undetectable. She tested positive for anti-GAD antibodies, and had a high-risk genotype - DRB1*09:01-DQB1*03:03 - for slowly progressive insulin-dependent diabetes mellitus (SPIDDM) in the HLA-DR/DQ region, confirming the diagnosis of SPIDDM. Dysglycemia in PWS is thought to be attributable to hyperphagia and obesity. However, the possibility of SPIDDM might be considered if the insulin secretory capacity is almost lost in patients with PWS.

Early clinical factors predicting the development of critical disease in Japanese patients with COVID-19: A single-center, retrospective, observational study

The factors predicting the progression of coronavirus disease‐2019 (COVID‐19) from mild to moderate to critical are unclear. We retrospectively evaluated risk factors for disease progression in Japanese patients with COVID‐19. Seventy‐four patients with laboratory‐confirmed COVID‐19 were hospitalized in our hospital between February 20, 2020, and June 10, 2020. We excluded asymptomatic, non‐Japanese, and pediatric patients. We divided patients into the stable group and the progression group (PG; requiring mechanical ventilation). We compared the clinical factors. We established the cutoff values (COVs) for significantly different factors via receiver operating characteristic curve analysis and identified risk factors by univariate regression. We enrolled 57 patients with COVID‐19 (median age 52 years, 56.1% male). The median time from symptom onset to admission was 8 days. Seven patients developed critical disease (PG: 12.2%), two (3.5%) of whom died; 50 had stable disease. Univariate logistic analysis identified an elevated lactate dehydrogenase (LDH) level (COV: 309 U/l), a decreased estimated glomerular filtration rate (eGFR; COV: 68 ml/min), lymphocytopenia (COV: 980/μl), and statin use as significantly associated with disease progression. However, in the Cox proportional hazards analysis, lymphocytopenia at admission was not significant. We identified three candidate risk factors for progression to critical COVID‐19 in adult Japanese patients: statin use, elevated LDH level, and decreased eGFR.

To evaluate risk factors for disease progression in Japanese patients with COVID‐19, we examined seventy‐four patients with laboratory‐confirmed COVID‐19.

Seven patients (12.2%) developed critical disease requiring mechanical ventilation, two (3.5%) of whom died.

We identified three candidate risk factors for progression to critical COVID‐19 in adult Japanese patients: statin use elevated LDH level and decreased eGFR.

Decreased Serum Adiponectin Level during Catecholamine Crisis in an Obese Patient with Pheochromocytoma

We herein report the case of a 37-year-old man with both pheochromocytoma and visceral fat accumulation and describe the sequential changes in his adiponectin levels throughout the clinical course from catecholamine crisis until the follow-up for adrenalectomy. His adiponectin level decreased during catecholamine crisis and increased after adrenalectomy. However, his adiponectin level decreased again at two years postoperatively when his visceral fat area greatly increased. This case suggests that catecholamines and visceral fat volume may affect adiponectin metabolism in subjects with pheochromocytoma, which may precipitate cardiovascular complications in this endocrine disease.

High glycated albumin (GA) levels and the GA/HbA1c ratio in patients with insulin autoimmune syndrome

Insulin autoimmune syndrome (IAS) involves not only fasting hypoglycemia, but also postprandial hyperglycemia. In the present study, we hypothesized that glycated albumin (GA) levels and the GA/HbA1c ratio, which reflect fluctuations in plasma glucose levels, are elevated in IAS patients. Four IAS patients were enrolled in the present study. Thirty-two non-diabetic subjects matched for gender, age, and BMI were used as the control group. The fasting plasma glucose levels in the IAS patients were significantly lower than in the control group. However, the oral glucose tolerance test (OGTT) revealed impaired glucose tolerance or diabetes mellitus in all the IAS patients, and thus the OGTT 2-h plasma glucose levels were significantly higher than in the control group. The GA levels and the GA/HbA1c ratio in the IAS patients were significantly higher than in the control group, despite no significant difference in the HbA1c levels between the two groups. In one case in which IAS spontaneously went into remission, there was a significant correlation between anti-insulin antibodies and GA, but not HbA1c. Improvement in glucose fluctuations was observed by continuous glucose monitoring in another patient along with improvement in the clinical symptoms. Furthermore, anti-insulin antibodies, GA, and the GA/HbA1c ratio decreased, but HbA1c did not change significantly in three IAS patients along with the improvement in clinical symptoms. These results suggest that GA and the GA/HbA1c ratio are useful indicators for determining the level of disease activity in IAS patients.

Extent of weight reduction necessary for minimization of diabetes risk in Japanese men with visceral fat accumulation and glycated hemoglobin of 5.6-6.4

Aims/Introduction

Weight reduction improves glycemic control in obese men with glycated hemoglobin (HbA1c) of 5.6–6.4%, suggesting that it can prevent the development of diabetes in these patients. The aim of the present study was to quantify the amount of weight reduction necessary for minimization of diabetes risk in Japanese men with visceral fat accumulation.

Materials and Methods

The study participants were 482 men with an estimated visceral fat area of ≥100 cm², HbA1c of 5.6–6.4%, fasting plasma glucose (FPG) of <126 mg/dL or casual plasma glucose <200 mg/dL. They were divided into two groups based on weight change at the end of the 3-year follow-up period (weight gain and weight loss groups). The weight loss group was classified into quartile subgroups (lowest group, 0 to <1.2%: second lowest group, ≥1.2 to <2.5%: second highest group, ≥2.5 to <4.3%: highest group, ≥4.3% weight loss). The development of diabetes at the end-point represented a rise in HbA1c to ≥6.5% or FPG ≥126 mg/dL, or casual plasma glucose ≥200 mg/dL.

Results

The cumulative incidence of diabetes at the end of the 3-year follow-up period was 16.2% in the weight gain group and 10.1% in the weight loss group (P not significant). The incidence of diabetes was significantly lower in the highest weight loss group (3.1%), but not in the second highest, the second lowest and the lowest weight loss groups (9.7, 10.1 and 18.3%), compared with the weight gain group.

Conclusions

Minimization of the risk of diabetes in Japanese men with visceral fat accumulation requires a minimum of 4–5% weight loss in those with HbA1c of 5.6–6.4%.

Differences in emotional distress among inpatients with type 1, obese type 2, and non-obese type 2 diabetes mellitus

Objective The purpose of this study was to determine the differences in emotional distress among three groups of inpatients with type 1, obese type 2, and non-obese type 2 diabetes during hospitalization. Methods The 42 participating inpatients were divided into three groups: type 1 diabetes (n=11), obese type 2 diabetes [body mass index (BMI) ≥25 kg/m(2); n=24], and non-obese type 2 diabetes (BMI <25 kg/m(2); n=7). The Problem Areas in Diabetes (PAID) scale, which is a self-administered questionnaire to assess emotional distress in the patients with diabetes, was performed at admission and discharge. Results The total PAID score was similar and tended to improve during hospitalization in all three groups, although there were differences among the groups in the scores of particular questions. At admission, the score of the question "worrying about low blood sugar reactions?" was significantly different among the three groups and highest in the patients with type 1 diabetes. At discharge, the score of "not accepting diabetes?" was significantly different among the three groups and highest in the patients with non-obese type 2 diabetes, while that of "feeling unsatisfied with your diabetes physician?" was significantly different among the three groups and highest in the patients with obese type 2 diabetes. The score of "feelings of deprivation regarding food and meals?" significantly worsened in the patients with obese type 2 diabetes during hospitalization compared with the patients in with non-obese type 2 diabetes. Conclusion The characteristics of emotional distress during hospitalization varied among the patients with the three types of diabetes, thus emphasizing the importance of tailoring support according to the type of diabetes.

Liraglutide is effective in type 2 diabetic patients with sustained endogenous insulin-secreting capacity

Aims/Introduction:  Recently, glucagon-like peptide-1 (GLP-1) receptor agonists of liraglutide have become available in Japan. It has not yet been clarified what clinical parameters could discriminate liraglutide-effective patients from liraglutide-ineffective patients.

MATERIALS AND METHODS

  We reviewed 23 consecutive patients with type 2 diabetes admitted to Osaka University Hospital for glycemic control. All of the patients were treated with diet plus insulin (or plus oral antidiabetic drugs) to improve fasting plasma glucose (FPG) and postprandial glucose below 150 and 200 mg/dL, respectively. After insulin secretion and insulin resistance were evaluated, insulin was replaced by liraglutide. The efficacy of liraglutide was determined according to whether glycemic control was maintained at the target levels.

RESULTS

  Liraglutide was effective in 13 of 23 patients. There were significant differences in the parameters of insulin secretion, including fasting C-peptide (F-CPR), C-peptide index (CPI), insulinogenic index (I.I.) and urine C-peptide (U-CPR), between liraglutide-effective and -ineffective patients. The duration of diabetes was significantly shorter in liraglutide-effective patients than in liraglutide-ineffective patients. In receiver operating characteristic analyses, the cut-off value for predicting the efficacy of liraglutide was 0.14 for I.I., 1.1 for CPI, 1.5 ng/mL for F-CPR, 33.3 μg/day for U-CPR and 19.5 years for duration of type 2 diabetes.

CONCLUSIONS

  Insulin secretion evaluated by F-CPR, CPI, I.I., U-CPR and the duration of type 2 diabetes were useful parameters for predicting the efficacy of liraglutide in patients with type 2 diabetes. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00168.x, 2011).

Predictors of deterioration of glucose tolerance and effects of lifestyle intervention aimed at reducing visceral fat in normal glucose tolerance subjects with abdominal obesity

Aims/Introduction:  The aim of the present study was to determine the predictors of deterioration of glucose tolerance in individuals with normal glucose tolerance (NGT) and abdominal obesity, and whether a lifestyle intervention to reduce visceral fat is effective in these individuals.

Materials and Methods:  The study subjects were 251 individuals who had abdominal obesity with certain risk factors (hypertension, high fasting plasma glucose (FPG), elevated hemoglobin A_1c (HbA_1c), dyslipidemia and hyperuricemia) and underwent oral glucose tolerance test (OGTT) in 2004 and 2005.

Results:  Using the area under the receiver operating characteristic curve, we found that PG at 0 min, 60 min, and area under the curve (AUC) of glucose from 0 to 120 min (AUC [glucose_0–120]) in OGTT were significant predictors of deterioration of glucose tolerance, with optimal cut‐off values of 95 mg/dL, 158 mg/dL and 271 mg h/dL, respectively. Although the rate of deterioration of glucose tolerance didn’t decrease with reductions in visceral fat area (VFA) over the 1‐year period in subjects with NGT, the rate tended to decrease with reductions in VFA in high‐risk NGT subjects (PG at 0 min > 95 or at 60 min > 158, or AUC [glucose_0–120] > 271).

Conclusions:  These results suggest that reduction of visceral fat over 1 year might not be beneficial in all subjects with NGT, but is beneficial in high‐risk NGT. We propose that individuals with values of the aforementioned predictors higher than the cut‐off levels, even those with NGT, should receive a lifestyle intervention program aimed at reducing visceral fat to prevent deterioration of glucose tolerance. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00080.x, 2011)

Usefulness of the insulin tolerance test in patients with type 2 diabetes receiving insulin therapy

Aims/Introduction

To establish the validity of the plasma glucose disappearance rate (KITT), derived from an insulin‐tolerance test (ITT), for evaluating the insulin sensitivity of patients with type 2 diabetes after insulin therapy.

Materials and Methods

In the first arm of the study, 19 patients with poorly controlled diabetes were treated with insulin and underwent an ITT and a euglycemic clamp test (clamp‐IR). The relationship between the insulin resistance index, as assessed by both the clamp‐IR and KITT tests, was examined. In the second arm of the study, the relationships between KITT values and various clinical parameters were investigated in 135 patients with poorly controlled diabetes, after achieving glycemic control with insulin.

Results

In study 1, a close correlation between KITT and the average glucose infusion rate during the last 30 min of the standard clamp‐IR test (M‐value) was noted (P < 0.001). In study 2, body mass index (P = 0.0011), waist circumference (P = 0.0004), visceral fat area (P = 0.0011) and the log‐transformed homeostasis model assessment of insulin resistance value (P = 0.0003) were negatively correlated with the log‐transformed KITT. High‐density lipoprotein cholesterol (P = 0.0183), low‐density lipoprotein cholesterol (P = 0.0121) and adiponectin (P = 0.0384) levels were positively correlated with the log‐transformed KITT.

Conclusions

The ITT is a valid and useful test for evaluating the insulin sensitivity of patients with diabetes, even after treatment with insulin.

Weight reduction is associated with improvement of glycemic control in Japanese men, whose hemoglobin A1C is 5.6-6.4%, with visceral fat accumulation, but not without visceral fat accumulation

Aims/Introduction

The aim of the present study was to determine whether weight reduction is associated with improvement of glycemic control in non‐obese and obese subjects with or without visceral fat accumulation, whose hemoglobin A1c (A1C) is 5.6–6.4%.

Materials and Methods

A total of 798 male subjects whose A1C levels were between 5.6% and 6.4% were divided into subgroups based on body mass index (BMI) and/or estimated visceral fat area (eVFA), and were analyzed with respect to the relationships between 1‐year changes in BMI (ΔBMI) and A1C (ΔA1C).

Results

In both the BMI ≥25 and BMI <25 groups, ΔA1C correlated positively with ΔBMI (BMI ≥25 (n = 321): r = 0.236, P < 0.0001; BMI <25 (n = 477): r = 0.095, P = 0.0387) although the r‐value was very small for the latter group. In addition, for the group with eVFA ≥100 cm² (n = 436), ΔA1C correlated positively with ΔeVFA (r = 0.150, P = 0.0017), but this correlation was not found for the eVFA <100 cm² group (n = 339, P = 0.3505). Furthermore, ΔA1C positively correlated with ΔBMI for the groups in BMI ≥25 with eVFA >100 cm² (n = 293, r = 0.256, P < 0.0001) and BMI <25 with eVFA ≥100 cm² (n = 145, r = 0.250, P = 0.0024), but not for the groups in BMI ≥25 with eVFA <100 cm² (n = 28, P = 0.6401) nor BMI <25 with eVFA <100 cm² (n = 332, P = 0.6605).

Conclusions

These results suggest that the assessment of visceral fat, rather than BMI, might be more important in identifying subjects in whom lifestyle intervention aiming at weight reduction could be effective to prevent diabetes. This trial was registered with University Hospital Medical Information Network Clinical Trials Registry (no. UMIN 000002391).

Homeostasis model assessment of insulin resistance for evaluating insulin sensitivity in patients with type 2 diabetes on insulin therapy

Homeostasis model assessment of insulin resistance (HOMA-IR) is a simple and useful method for evaluating insulin sensitivity. But it is difficult to apply to type2 diabetes patients treated with insulin. We have devised a method for measuring HOMA-IR and investigated the validity of HOMA-IR for evaluating insulin sensitivity in patients with type 2 diabetes on insulin therapy. In the first arm of the study, 19 poorly controlled diabetic subjects were treated with insulin and underwent euglycemic clamp study. Then the relationship between insulin resistance index assessed by the clamp test (clamp-IR) and HOMA-IR was investigated in these subjects. Log transformed HOMA-IR correlated with log transformed M/I values derived from the standard euglycemic clamp (r=-0.753, p=0.002). In the second arm of the study, we investigated the relationship between HOMA-IR and various clinical parameters in 156 patients with poorly controlled diabetes after glycemic control. Log transformed HOMA-IR correlated negatively with age (r=-0.292, p=0.0002), HDL-C (r=-0.342, p<0.0001), log transformed serum adiponectin (r=-0.309, p=0.0006) and log transformed KITT (r=-0.264, p=0.0009), and positively with body mass index (r=0.499, p<0.0001), waist circumstance (r=0.461, p<0.0001), visceral fat area (r=0.401, p<0.0001), diastolic blood pressure (r=0.223, p=0.0054), log transformed triglyceride (r=0.497, p<0.0001), urinary CPR (r=0.216, p=0.0099), ΔCPR of glucagon stimulation test (r=0.496, p<0.0001) and log transformed insulinogenic index (r=0.325, p=0.0002). These results suggest that HOMA-IR is a useful test for the evaluation of insulin sensitivity even in patients with type 2 diabetes treated with insulin.

Insulin autoimmune syndrome in a health supplement user: the effectiveness of cornstarch therapy for treating hypoglycemia

A 70-year-old woman with no history of diabetes was admitted to the hospital for the management of hypoglycemia. Her fasting plasma glucose level was 54 mg/dL with an extremely high serum immunoreactive insulin level (1210 μU/mL). She had high titers of anti-insulin antibodies and exhibited the DRB1*0406 genotype for HLA-DR4, leading to a diagnosis of insulin autoimmune syndrome. She had been taking several health preparations for approximately 10 years; however, all were thiol group-free. Due to frequent episodes of nocturnal hypoglycemia, the health preparations were discontinued and the patient was treated with cornstarch. This protocol successfully ameliorated the hypoglycemic episodes and normalized the patient's laboratory and serological test results.

Insulin-secretion capacity in normal glucose tolerance, impaired glucose tolerance, and diabetes in obese and non-obese Japanese patients

Aims/Introduction:  Pronounced reduction of insulin secretion in response to a rise in glucose level has been reported in Japanese patients compared with Caucasian patients, but the mean body mass index (BMI) is also lower in Japanese patients. As BMI is a determinant of insulin secretion, we examined insulin-secretion capacity in obese and non-obese Japanese patients.

MATERIALS AND METHODS

  Using the oral glucose tolerance test (OGTT), we estimated the insulin-secreting capacity in obese (BMI ≥ 25) and non-obese (BMI < 25) Japanese patients, including 1848 patients with normal glucose tolerance (NGT), 321 patients with impaired glucose tolerance (IGT) and 69 diabetes (DM) patients.

RESULTS

  The insulinogenic index (I.I.), calculated by dividing the increment in serum insulin by the increment in plasma glucose from 0 to 30 min during OGTT, decreased from NGT to IGT and to DM in patients with and without obesity. In patients with NGT, IGT and DM, the I.I. values of obese patients were higher than those of the non-obese patients. The peak of insulin concentration in OGTT appeared at 60 min in NGT and at 120 min in IGT in both obese and non-obese patients, but in DM it was observed at 120 min in obese patients and at 60 min in non-obese patients.

CONCLUSIONS

  These results show that early-phase insulin secretion in obese Japanese patients is higher than in non-obese patients in all stages of glucose tolerance, and delayed insulin-secretion capacity is also conserved in obese Japanese patients, even in IGT and DM, which is similar to Caucasian patients. (J Diabetes Invest, doi:10.1111/j.2040-1124.2011.00180.x, 2011).

Carotid intima-media thickness, but not visceral fat area or adiponectin, correlates with intracoronary stenosis detected by multislice computed tomography in people with type 2 diabetes and hypertension

We investigated the relationship between intracoronary stenosis detected by multislice computed tomography and various clinical parameters in type 2 diabetic patients with hypertension treated with candesartan (n=42). The results showed that carotid intima-media thickness, but not visceral fat area or adiponectin, correlated significantly with intracoronary stenosis (p<0.05).

Preoperative insulin secretion ability and pancreatic parenchymal thickness as useful parameters for predicting postoperative insulin secretion in patients undergoing pancreaticoduodenectomy

Periampullary malignant neoplasms have been increasing in Japan, mainly in response to an increase in the incidences of pancreatic cancer, and glucose intolerance due to deterioration of insulin secretion is an important problem. We investigated preoperative parameters to predict postoperative insulin secretion and the need for insulin therapy in patients undergoing pancreaticoduodenectomy (PD). Thirty-six patients with malignant neoplasms of periampullary lesions were enrolled. Preoperative pancreatic parenchymal thickness was evaluated by computed tomography. Insulin secretion and glucose tolerance were evaluated by a 75-g oral glucose tolerance test and an intravenous glucagon loading test. The relationships between postoperative insulin secretion and preoperative parameters and the cut-off values for predicting the need for postoperative insulin therapy for glycemic control were investigated. Pancreatic parenchymal thickness and other preoperative parameters, including the increment of serum C-peptide (Δ C-peptide), fasting plasma C-peptide (F-CPR), insulinogenic index (I.I.) and fasting plasma glucose (FPG), were significantly associated with postoperative insulin secretion. Multiple regression analyses revealed that preoperative Δ C-peptide or F-CPR was the most significant determinant of postoperative insulin secretion, followed by pancreatic parenchymal thickness. In the receiver operating characteristic curve, the best preoperative cut-off values for predicting the need for postoperative insulin therapy were a Δ C-peptide of 0.65 ng/mL, a F-CPR of 0.85 ng/mL and a pancreatic parenchymal thickness of 6.0 mm. Both preoperative insulin secretion and pancreatic parenchymal thickness effectively predict postoperative insulin secretion and identify subjects who need postoperative insulin therapy for glycemic control.

Cross-sectional and longitudinal study of association between circulating thiobarbituric acid-reacting substance levels and clinicobiochemical parameters in 1,178 middle-aged Japanese men - the Amagasaki Visceral Fat Study

Background

Circulating thiobarbituric acid-reacting substance (TBARS) levels, a marker of systemic oxidative stress, are predictive of cardiovascular events. However, they has not been evaluated in Japanese, especially with regard to the factors that contribute to the changes in circulating TBARS levels. We investigated the cross-sectional and longitudinal relationships between circulating TBARS levels and various clinicobiochemical parameters in middle-aged men.

Methods

In this population-based study (The Amagasaki Visceral Fat Study), 1,178 Japanese male urban workers who had undergone health check-ups in 2006, 2007 and 2008 and were not on medications for metabolic disorders during the follow-up period, were enrolled. Serum TBARS levels were measured by the method of Yagi. The estimated visceral fat area (eVFA) by bioelectrical impedance was measured annually. After health check-ups, subjects received health education with lifestyle modification by medical personnel.

Results

The number of cardiovascular risk factors (hypertension, hyperglycemia, low HDL-C, hypertriglyceridemia, hyperuricemia, hyper-LDL-C and impaired renal function) augmented with the increases in log-eVFA (p < 0.0001) and log-TBARS (p < 0.0001). The combination of TBARS and eVFA had a multiplicative effect on risk factor accumulation (F value = 79.1, p = 0.0065). Stepwise multiple regression analysis identified log-eVFA, as well as age, log-body mass index (BMI), LDL-C, log-adiponectin, γ-glutamyl transpeptidase (γ-GTP) and uric acid as significant determinants of log-TBARS. Stepwise multiple regression analysis identified one-year changes in eVFA as well as BMI, γ-GTP and estimated glomerular filtration rate (eGFR) as significant determinants of one-year change in TBARS, and biennial changes in eVFA as well as BMI and γ-GTP, eGFR as significant determinants of biennial change in TBARS.

Conclusions

The present study showed a significant cross-sectional and longitudinal correlation between TBARS and eVFA, as well as BMI and γ- GTP, eGFR. Visceral fat reduction may independently associate with the improvement in systemic ROS in middle-aged Japanese men.

Trial Registration

The Amagasaki Visceral Fat Study UMIN000002391.

Health education "Hokenshido" program reduced metabolic syndrome in the Amagasaki visceral fat study. Three-year follow-up study of 3,174 Japanese employees

OBJECTIVE

The aim of this study was to evaluate the effects of health checkup and the health education "Hokenshido" program based on the concept that visceral fat accumulation causes metabolic syndrome (MetS), leading to cardiovascular disease (CVD).

METHODS AND SUBJECTS

Based on the Japanese definition of metabolic syndrome, in the annual health checkup for general subjects, the measurement of waist circumference and use of "Where am I?" chart on the way to develop atherosclerosis were introduced. The study group comprised 3,174 Japanese employees [2,440 males (46±11 years, mean ± SD), 734 females (43±10 years)], who underwent annual health checkup in 2003, 2004, and 2005. The medical staff provided "Hokenshido" for subjects assessed as having MetS and/or at high risk for CVD.

RESULTS

The prevalence of the MetS in 2003, 2004 and 2005 decreased in males (20.8%, 17.2%, 14.4%, p<0.001) and females (3.0%, 2.2%, 1.9%, p=0.359), respectively. Among subjects with MetS at baseline, the number of subjects with MetS significantly decreased in males (508, 287, 247, p<0.0001) and females (22, 8, 6, p<0.0001), respectively. Mean waist loss was 1.6 cm in males (<0.0001) and 1.5 cm in females (<0.001). Among subjects with metabolic syndrome at baseline, the mean waist loss was 2.5 cm in males (<0.0001) and 3.9 cm in females (<0.05). Fatal atherosclerotic vascular events were not recorded in this study period.

CONCLUSION

Health check-up and the "Hokenshido" program reduced the prevalence of the MetS, which might lead to prevention of CVD.

Insulin tolerance test predicts the effectiveness of insulin sensitizers in japanese type 2 diabetic patients

INTRODUCTION

The purpose of this study was to assess the efficacy of the insulin tolerance test (ITT) in predicting the effectiveness of insulin sensitizers in type 2 diabetic patients.

METHODS

We retrospectively reviewed 360 consecutive patients with type 2 diabetes admitted to Osaka University Hospital, Japan. In 163 of these hospitalized patients, insulin resistance was evaluated by the ITT after their blood glucose level was ameliorated. We then analyzed the association between their clinical characteristics and their glycemic control 6 months after discharge.

RESULTS

The rate constant for plasma glucose disappearance, K (ITT), was negatively correlated with body mass index (BMI), waist circumference (WC), and visceral fat area (VFA). The median value of K (ITT) was 1.56 (%/min). In the K (ITT) > 1.56 group (n=81), hemoglobin A(1c) (HbA(1c)) significantly increased in both patients treated with insulin sensitizers (n=10) and patients not treated with insulin sensitizers (n=71). In the K (ITT) ≤1.56 group (n=82), HbA(1c) significantly increased in patients not treated with insulin sensitizers (n=60); however, it was maintained well in the patients treated with insulin sensitizers (n=22). When the patients were divided and analyzed according to the median values of BMI, WC, or VFA, the glycemic control change was not different between the two groups with insulin sensitizers for each parameter.

CONCLUSION

Insulin sensitizers were effective in type 2 diabetic patients with high insulin resistance estimated by the ITT. The ITT could be useful to predict the effectiveness of insulin sensitizers.

Absolute value of bioelectrical impedance analysis-measured visceral fat area with obesity-related cardiovascular risk factors in Japanese workers

AIM

The accumulation of Visceral fat is known to precede metabolic disorders and atherosclerosis. This study aimed to determine the relationships between body mass index (BMI), waist circumference (WC), estimated visceral fat area (eVFA) measured by bioelectrical impedance analysis (BIA), and obesity-related cardiovascular risk factors.

METHODS

The study population was 2,870 middle-aged Japanese employees (males/females=2,322/ 548), who had undergone a health check-up.

RESULTS

In the receiver operating characteristic (ROC) curve, the cutoff levels yielding maximal sensitivity plus specificity for predicting the prevalence of ≥ 2 risks were, 24.5 kg/m(2) for BMI, 84.6 cm for WC, and 111 cm(2) for eVFA in males, and 23.6 kg/m(2), 81.5 cm, and 67 cm(2) in females. The average number of risk factors was over 1.0 in those with a BMI ≥ 25 kg/m(2) and with a WC ≥ 85 cm for males, ≥ 28 kg/m(2) and ≥ 95 cm respectively for females, and those with an eVFA ≥ 100 cm(2) for both males and females. In males, it was around 1.0 with cutoff levels of BMI, WC, and eVFA from the ROC curve. However, in females, it was around 0.6, because the prevalence of subjects with obesity and multiple risks was very low.

CONCLUSIONS

These results suggested that the cutoff level for visceral fat reduction should be set based on an absolute value of risk factors, rather than a calculated value. In regular health check-up, it may be useful to set an absolute cutoff value for eVFA at 100 cm(2) as criteria to screen for multiple obesity-related cardiovascular risk factors.

Relationship between visceral fat accumulation and urinary albumin-creatinine ratio in middle-aged Japanese men

OBJECTIVE

Chronic kidney disease including microalbuminuria relates to cardiovascular disease (CVD). Microalbuminuria is also known to be a marker of generalized endothelial dysfunction. The metabolic syndrome which encompasses visceral fat accumulation and various metabolic disorders, has also an increase in albuminuria and relates to CVD. However, the relationship between visceral fat accumulation and albuminuria remains to be defined. The present study investigated the relationship between visceral fat accumulation and urinary albumin-creatinine ratio (UACR) in Japanese men.

METHODS

This study group comprised 1990 Japanese male subjects, who were employees of a city office, had undergone annual health check-up. Urinary albumin was collected from a single spot urine specimen collected anytime between morning and afternoon. Visceral fat area was estimated (eVFA) by the bioelectrical impedance analysis method.

RESULTS

Log-UACR correlated with age, log-body mass index (BMI), log-waist circumference (WC), log-eVFA, log-adiponectin, blood pressure, serum lipids and hemoglobin A1c (HbA1c). Stepwise multiple regression analysis identified log-eVFA, as well as HbA1c, blood pressure, log-TG, and age, as a significant determinant of log-UACR. Moreover, subjects with eVFA > or = 100 cm(2) had significantly higher UACR than those with eVFA <100 cm(2), irrespective of BMI. UACR was significantly worse in subjects with high numbers of metabolic risk factors, and moreover in subjects with eVFA > or = 100 cm(2) than in those with eVFA <100 cm(2).

CONCLUSION

These results suggested that visceral fat accumulation is associated with an increase in UACR. Evaluation of both visceral fat accumulation and urinary albumin may be important for preventing atherosclerotic diseases.

Glucagonoma diagnosed by arterial stimulation and venous sampling (ASVS)

To identify the location of pancreatic endocrine tumors, arterial stimulation and venous sampling (ASVS) is known to be useful for insulinoma and gastrinoma, but its usefulness for glucagonoma has not been verified to date. Here we report a case of glucagonoma that was diagnosed by ASVS with calcium loading, in which an approximately 6-fold increase of glucagon was observed in the splenic artery territory. MEN1 gene analysis verified the presence of a mutation and the glucagonoma was confirmed after operation. In conclusion, ASVS could be useful for the diagnosis of glucagonoma.

PGC-1alpha Gly482Ser polymorphism is associated with the plasma adiponectin level in type 2 diabetic men

Peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1alpha) is a multifunctional transcriptional regulator for the pathways controlling mitochondrial biogenesis, oxidative metabolism, and glucose homeostasis. Genetic studies have suggested that Gly482Ser polymorphism of the PGC-1alpha gene is associated with a higher risk of type 2 diabetes, obesity, and hypertension. Adiponectin is an antidiabetic and antiatherogenic adipocytokine that is specifically produced by adipose tissue, and the transcription of the adiponectin gene is regulated by PPARgamma. In this study, we examined the effect of Gly482Ser polymorphism on the plasma adiponectin level in Japanese type 2 diabetics. The Gly482Ser genotype was associated with a lower plasma adiponectin level in type 2 diabetic men, but not in type 2 diabetic women. The impact of this variation on the adiponectin promoter was also assessed by a reporter gene assay, but there was no significant difference between activation by the wild type and Gly482Ser- PGC-1alpha proteins, indicating that this variation itself has no functional effect. Evaluation of the pattern of linkage disequilibrium revealed that the Gly482Ser polymorphism is located in the largest linkage disequilibrium block of the PGC-1alpha gene. Therefore the observed gender-specific association between PGC-1alpha and the plasma adiponectin level may reflect linkage disequilibrium of Gly482Ser polymorphism with other causative variations.

Impaired early insulin secretion in Japanese type 2 diabetes with metabolic syndrome

Although it is widely believed that type 2 diabetics with metabolic syndrome (MS) have insulin resistance, the beta-cell function of these patients is largely unknown. We evaluated the characteristics of insulin secretion in Japanese type 2 diabetics with MS after minimizing the influence of glucotoxity. A 75-g OGTT was performed in 192 diabetic subjects and 275 subjects with normal glucose tolerance (NGT). Although there was no significant difference of the AUC (insulin(0-120)) between the MS group and the NGT group, the insulinogenic index (I.I.) was significantly lower in MS patients compared with NGT subjects. The BMI, maximum BMI, waist circumference, and VFA were all positively correlated with I.I. in the MS group (r=0.298-0.376). By stepwise multiple regression analysis, the BMI was shown to be an independent determinant of I.I. in the MS group (standardized regression coefficient: 0.376, p=0.0004), and it accounted for 13% of the variance in I.I. The impaired I.I. was also found in the MS group with untreated type 2 diabetes. These results indicate that early insulin secretion is impaired in type 2 diabetics with MS. The positive association between BMI and I.I. in diabetics with MS may be explained by beta-cell compensation for reduced insulin sensitivity.

The -1535 promoter variant of the visfatin gene is associated with serum triglyceride and HDL-cholesterol levels in Japanese subjects

Visfatin is a novel adipocytokine that is expressed by the visceral fat cells. We investigated the role of genetic variation in the visfatin gene in the pathophysiology of type 2 diabetes and clinical variables in Japanese subjects. The 11 exons, and the promoter region of the visfatin gene were screened for single nucleotide polymorphisms (SNPs) by PCR-direct sequencing. We found SNPs in the promoter region (SNP - 1535T>C), exon 2 (SNP + 131C>G, Thr44Arg), and exon 7 (SNP + 903G>A). The allele and genotype frequencies of these SNPs showed no significant differences between 200-448 diabetic and 200-333 control subjects. However, the -1535T/T genotype was associated with lower serum triglyceride levels (T/T vs. T/C + C/C (p = 0.015) and T/T vs. C/C (p = 0.043)) and higher HDL-cholesterol levels (T/T vs. C/C, p = 0.0496) in the nondiabetic subjects. Reporter gene assay of 3T3-L1 adipocytes revealed that the promoter activity of -1535T and -1535C was similar, suggesting that the observed association may reflect linkage disequilibrium between -1535T>C and causative variations of the visfatin gene.

Relationship between the serum uric acid level, visceral fat accumulation and serum adiponectin concentration in Japanese men

OBJECTIVE

Visceral fat accumulation is an underlying component of the metabolic syndrome (MetS). Hypoadiponectinemia is one of the key molecules of the MetS. In the present study, we investigated the relationship between the serum uric acid level, visceral fat accumulation and serum adiponectin concentration in Japanese men.

PATIENTS AND METHODS

The study group comprised 1,520 Japanese employed men (mean age: 45.6+/-10.4 years, +/- SD), who had undergone an annual health check-up both in 2004 and 2005. In addition to parameters measured in the annual health check-up, visceral fat area (VFA) and serum adiponectin concentration were measured by the bioelectrical impedance analysis method and a sandwich enzyme-linked immunosorbent assay (ELISA) system, respectively.

RESULTS

Visceral fat accumulation was identified in 56.1% of the subjects with hyperuricemia. There was significant positive correlation between visceral fat area and serum uric acid levels (r=0.223, p<0.0001), and negative correlation between serum adiponectin concentration and serum uric acid levels (r=-0.198, p<0.0001). The one-year change in VFA was associated with the one-year change in serum uric acid levels. Stepwise multiple regression analysis showed that VFA and the serum adiponectin concentration were significant explanatory variables for serum uric acid levels.

CONCLUSION

Hyperuricemia is significantly associated with visceral fat accumulation and hypoadiponectinemia in Japanese men.

Aneurysm of the gastroduodenal artery

We report a case of gastroduodenal arterial aneurysm incidentally discovered by abdominal ultrasonogram, in which three-dimensional computed tomography (3D-CT) was useful for diagnosis. An 85-year-old man was hospitalized because of fever and liver dysfunction. Carcinoma of the papilla of Vater was diagnosed by endoscopic retrograde cholangio-pancreatography, while abdominal ultrasonogram and CT scan revealed a round mass measuring 6.2x4.1 cm on the ventral side of the pancreatic head. Three-dimensional CT demonstrated that the mass arose from a branch of the common hepatic artery and projected downward, indicating a gastroduodenal arterial aneurysm. During pancreatoduodenectomy and aneurysmectomy, it was confirmed that this aneurysm arose from the gastroduodenal artery.

Identification of a single cytosine base insertion mutation at Arg-597 of the beta subunit of the human epithelial sodium channel in a family with Liddle's disease

We describe a family with Liddle's disease caused by a novel mutation of the beta subunit of the human epithelial sodium channel (ENaC). A 15-year-old Japanese female was referred to our outclinic because of hypertension. The physical examination showed no abnormal findings except mild hypertension, but the laboratory data revealed low levels of plasma renin activity, plasma aldosterone and serum potassium. A comprehensive analysis of steroid hormones showed only high levels of urinary free cortisol and 17-hydroxycorticosteroids. During loading tests, blood pressure and serum potassium responded well to triamterene and slightly to spironolactone, but did not respond to dexamethasone. In addition, the normal ratio of tetrahydrocortisol plus 5alpha-tetrahydrocortisol to tetrahydrocortisone in a 24 h urinary excretion test strongly suggested a diagnosis of Liddle's disease rather than apparent mineralocorticoid excess syndrome. DNA sequence analysis of members of this family revealed a single cytosine base insertion at Arg-597 of the beta human ENaC in the proband and her mother, leading to a loss of the last 34 amino acids from the normally encoded protein as the result of a frameshift. We conclude that a de novo cytosine insertion into the final exon of the C-terminus of the beta human ENaC is responsible for Liddle's disease in this Japanese family.

Hypogenesis of right hepatic lobe accompanied by portal hypertension: case report and review of 31 Japanese cases

We report a rare case of hypogenesis of the right lobe of the liver with portal hypertension and a review of 31 cases of agenesis or hypogenesis of the right hepatic lobe reported in Japan. A 74-year-old man consulted our hospital for further examination after a mass screening for gastric cancer. On physical examination liver enlargement was palpable, but liver function tests were normal. Abdominal ultrasonography, computed tomography, technetium-99m liver scintigraphy, and endoscopic retrograde cholangiopancreatography revealed a small right hepatic lobe and moderate splenomegaly, in contrast to a hypertrophic lateral segment of the left hepatic lobe, as well as ectopic dislocation of the gallbladder. Endoscopic examination revealed esophageal varices, indicating portal hypertension. Abdominal angiography demonstrated mild shunt flow between the hepatic artery feeding from the gastroduodenal artery and the portal vein. A biopsy specimen taken from both lobes of the liver showed normal liver tissue histologically. Based on these findings, we made a definite diagnosis of hypogenesis of the right lobe of the liver with portal hypertension. The present case appears to be the first such case accompanied by portal hypertension reported in Japan.

An adult case of Cockayne syndrome without sclerotic angiopathy

We report an autopsy case of Cockayne syndrome (CS). A 40-year-old Japanese woman was admitted to our hospital for cachexia. She had displayed the striking features of CS, including dwarfism, mental retardation, neural deafness, ataxia, intracranial calcifications, and progeria since her childhood. Endocrinological examinations suggested normal pituitary function and a disorder of the hypothalamus or the cerebrum. She died of acute pneumonia at the age of 42. Autopsy findings showed typical abnormalities in the central nervous system compatible with CS; however, no atherosclerotic change was observed in the systemic arteries.

Effects of thyroidectomy on thyrotropin-releasing hormone (TRH) and somatotropin release-inhibiting factor (SRIF) patterns in intrahypophysial microdialysates in rats

The effects of thyroidectomy on patterns of TRH and somatotropin release-inhibiting factor (SRIF) release from the hypothalamus were investigated by using a microdialysis technique. Thyroidectomized and sham-operated rats underwent placement of a guide cannula into the anterior pituitary gland to obtain dialysates, or implantation of an intravenous cannula into the right atrium for blood sampling. Seven days postoperatively dialysates were collected at a flow rate of 2 microliters/min every 1 h. TRH concentrations in dialysates from thyroidectomized rats (0.43 +/- 0.2 pg/h) were significantly higher than those from control rats (0.17 +/- 0.02 pg/h). In contrast, SRIF concentrations in dialysates from thyroidectomized rats (2.45 +/- 0.05 pg/h) were significantly lower than those from control rats (3.80 +/- 0.22 pg/h). In addition, plasma TSH concentrations in thyroidectomized rats (24.8 +/- 0.5 ng/ml) were increased compared with those in control rats (2.5 +/- 0.1 ng/ml), and plasma GH concentrations were decreased from 68.6 +/- 6.4 ng/ml in control rats to 21.2 +/- 0.6 ng/ml in thyroidectomized rats. These findings indicate that TRH and SRIF releases from the hypothalamus are detectable by microdialysis method, and directly show the increase in TRH secretion and the decrease in SRIF secretion from hypothalamus in the hypothyroid state.

Thyrotropin-releasing hormone release in normal and hyperthyroid rats as measured by microdialysis

To measure the thyrotropin-releasing hormone (TRH) release from the hypothalamus in euthyroid and hyperthyroid states, we investigated the changes in TRH levels in the anterior pituitary of conscious male rats using an in vivo microdialysis technique. In the euthyroid rats (n = 18), TRH levels in the extracellular dialysates of the anterior pituitary varied from 1.0 to 101.0 pg/ml in a pulsatile fashion: 15.9 +/- 13.9 (mean +/- SD) pg/ml with 5.8 +/- 1.5 pulses/24 h. In the hyperthyroid rats (n = 5) who received L-thyroxine at 10 micrograms/100 g body weight for 7 days, TRH levels in the dialysates during 6 h was 3.6 +/- 1.7 pg/ml, and significantly lower (P < 0.05) than those of the control rats (15.5 +/- 14.1 pg/ml); the pulse frequency was unchanged. These findings demonstrated for the first time the existence of pulsatile TRH release from the hypothalamus, and showed that thyroid hormone inhibits TRH release by the reduction of pulse amplitude, but not of pulse frequency.

[Preoperative diagnosis of unroofed coronary sinus: a case report]

A 54-year-old man was admitted to our hospital because of exertional dyspnea. A second heart sound with fixed splitting and a systolic ejection murmur along the left sternal border was audible. The chest roentgenogram showed increased pulmonary vascularity, and the electrocardiogram showed incomplete right bundle branch block. Two-dimensional echocardiography in the parasternal view demonstrated a partition defect between the left atrium and the coronary sinus. Furthermore, transesophageal echocardiography revealed a left-to-right shunt flow into the coronary sinus through the defect. At these points, the patient was diagnosed as having a partially unroofed mid-portion of the coronary sinus. Unroofed coronary sinus is a cardiac anomaly rarely diagnosed prior to surgical operation. Two-dimensional echocardiography, especially transesophageal echocardiography, is useful for the preoperative diagnosis of unroofed coronary sinus.