Brown adipose tissue is involved in diet-induced thermogenesis and whole-body fat utilization in healthy humans.

BACKGROUND/OBJECTIVES: Brown adipose tissue (BAT) is a potential therapeutic target against obesity and diabetes through thermogenesis and substrate disposal with cold exposure. The role of BAT in energy metabolism under thermoneutral conditions, however, remains controversial. We assessed the contribution of BAT to energy expenditure (EE), particularly diet-induced thermogenesis (DIT), and substrate utilization in human adults. METHODS: In this cross-sectional study, BAT activity was evaluated in 21 men using 18F-fluoro-2-deoxy-D-glucose positron emission tomography combined with computed tomography (18F-FDG-PET/CT) after cold exposure (19 °C). The subjects were divided into BAT-positive (n=13) and BAT-negative (n=8) groups according to the 18F-FDG-PET/CT findings. Twenty-four hour EE, DIT and respiratory quotient were measured using a whole-room indirect calorimeter at 27 °C. RESULTS: Body composition, blood metabolites and 24-h EE did not differ between groups. DIT (%), calculated as DIT divided by total energy intake, however, was significantly higher in the BAT-positive group (BAT-positive: 9.7±2.5%, BAT-negative: 6.5±4.0%, P=0.03). The 24-h respiratory quotient was significantly lower (P=0.03) in the BAT-positive group (0.861±0.027) than in the BAT-negative group (0.889±0.024). CONCLUSION: DIT and fat utilization were higher in BAT-positive subjects compared to BAT-negative subjects, suggesting that BAT has a physiologic role in energy metabolism.

Cellular locations of proteinases and association with vesicles in Porphyromonas gingivalis.

We found that locations of arginine-specific gingipain (RGP) in the cellular fractions in the crude extract, envelope, vesicles, and culture supernatants were 48%, 16%, 17%, and 31%, respectively, and the corresponding values of lysine-specific gingipain (KGP) were 47%, 10%, 7%, and 36%, respectively. Although the molecular mass of RGP in the culture supernatant had been determined as 43 kDa, and that of KGP had been as 48 kDa, molecular masses of both proteinases solubilized from the vesicles were estimated to be over 1,500 kDa, since they eluted in the void volume of the column in the gel filtration on Sephacryl S-300. There was no reduction of molecular size by the following treatment with SDS, high-concentration NaCl, or urea. Interestingly, the occurrence of the macromolecular forms could not observed in other enzymes tested such as monopeptidyl, dipeptidyl, and tripeptidyl peptidases, as well as alkaline phosphatase. Therefore, occurrence of the macromolecular forms may be restricted to the proteinases. When the vesicle and culture supernatants containing free RGP and KGP were mixed and incubated, neither RGP nor KGP seemed to bind to vesicles. RGP bound to the vesicle was found to be more stable to heat treatment than the free form, suggesting that association of RGP with the vesicle caused heat stability of this enzyme.

Peripheral administration of κ-opioid receptor antagonist stimulates gonadotropin-releasing hormone pulse generator activity in ovariectomized, estrogen-treated female goats.

Pulsatile gonadotropin-releasing hormone (GnRH) secretion is indispensable for reproduction in mammals. Kisspeptin neurons in the hypothalamic arcuate nucleus (ARC), referred to as KNDy neurons because of the coexpression of neurokinin B and dynorphin A, are considered as components of the GnRH pulse generator that produces rhythmic GnRH secretion. The present study aimed to investigate if peripheral administration of PF-4455242, a κ-opioid receptor (KOR, a dynorphin A receptor) antagonist, facilitates pulsatile luteinizing hormone (LH) secretion and GnRH pulse generator activity in estrogen-treated ovariectomized Shiba goats to determine the possibility of using KOR antagonists to artificially control ovarian activities. PF-4455242 was intravenously infused for 4 h (1 or 10 µmol/kg body weight/4 h) or as a single subcutaneous injection (1 or 10 µmol/kg body weight). In a separate experiment, the same KOR antagonist (10 µmol/kg body weight/4 h) was intravenously infused during the recording of multiple unit activity (MUA) in the ARC that reflects the activity of the GnRH pulse generator to test the effects of KOR antagonist administration on GnRH pulse generator activity. Intravenous infusion and single subcutaneous injection of the KOR antagonist significantly increased the frequency of LH pulses compared with controls. Intravenous infusion of KOR antagonist also significantly increased the frequency of episodic bursts in the MUA. The present study demonstrates that peripherally administered KOR antagonist stimulates pulsatile LH secretion by acting on the GnRH pulse generator, and peripheral administration of PF-4455242 can be used to facilitate pulsatile LH secretion, which in turn facilitates ovarian activities in farm animals.

Evidence of involvement of neurone-glia/neurone-neurone communications via gap junctions in synchronised activity of KNDy neurones.

Pulsatile secretion of gonadotrophin-releasing hormone (GnRH)/luteinising hormone is indispensable for the onset of puberty and reproductive activities at adulthood in mammalian species. A cohort of neurones expressing three neuropeptides, namely kisspeptin, encoded by the Kiss1 gene, neurokinin B (NKB) and dynorphin A, localised in the hypothalamic arcuate nucleus (ARC), so-called KNDy neurones, comprises a putative intrinsic source of the GnRH pulse generator. Synchronous activity among KNDy neurones is considered to be required for pulsatile GnRH secretion. It has been reported that gap junctions play a key role in synchronising electrical activity in the central nervous system. Thus, we hypothesised that gap junctions are involved in the synchronised activities of KNDy neurones, which is induced by NKB-NK3R signalling. We determined the role of NKB-NK3R signalling in Ca2+ oscillation (an indicator of neuronal activities) of KNDy neurones and its synchronisation mechanism among KNDy neurones. Senktide, a selective agonist for NK3R, increased the frequency of Ca2+ oscillations in cultured Kiss1-GFP cells collected from the mediobasal hypothalamus of the foetal Kiss1-green fluorescent protein (GFP) mice. The senktide-induced Ca2+ oscillations were synchronised in the Kiss1-GFP and neighbouring glial cells. Confocal microscopy analysis of these cells, which have shown synchronised Ca2+ oscillations, revealed close contacts between Kiss1-GFP cells, as well as between Kiss1-GFP cells and glial cells. Dye coupling experiments suggest cell-to-cell communication through gap junctions between Kiss1-GFP cells and neighbouring glial cells. Connexin-26 and -37 mRNA were found in isolated ARC Kiss1 cells taken from adult female Kiss1-GFP transgenic mice. Furthermore, 18ß-glycyrrhetinic acids and mefloquine, which are gap junction inhibitors, attenuated senktide-induced Ca2+ oscillations in Kiss1-GFP cells. Taken together, these results suggest that NKB-NK3R signalling enhances synchronised activities among neighbouring KNDy neurones, and that both neurone-neurone and neurone-glia communications via gap junctions possibly contribute to synchronised activities among KNDy neurones.

Synpolydactyly of the hand: a radiographic classification.

UNLABELLED: Synpolydactyly is an uncommon congenital anomaly characterized by polydactyly with syndactyly in the central hand. The purpose of this investigation was to develop and assess the reliability of a radiographic classification system for synpolydactyly. We identified 56 hands with central synpolydactyly and developed a radiographic classification system that categorizes by the location within the hand, the bony level of polydactyly, and the presence of a delta phalanx. Four paediatric hand surgeons independently reviewed each radiograph to establish reliability. There was exact agreement among raters in 40 cases (71%). The inter-rater reliability was 0.97 and intra-rater reliability was at least 0.87. Seven of 16 bilateral cases had symmetric deformity classification. The most common presentations were types 1A and 2A. We present a new, reliable radiographic classification system for synpolydactyly that will allow improved communication between clinicians and serve as a foundation for future investigations. LEVEL OF EVIDENCE: 2.

Urinary normetanephrine and metanephrine measured by radioimmunoassay for the diagnosis of pheochromocytoma: utility of 24-hour and random 1-hour urine determinations.

To validate the clinical usefulness of recently developed normetanephrine (NM) and metanephrine (M) RIA for the diagnosis of pheochromocytoma, urinary excretion of catecholamines and these metabolites were determined in 30 normal subjects, 40 patients with essential hypertension, 30 patients who were suspected to have but ultimately proven not to have a pheochromocytoma (pheochromocytoma-suspect), and 31 patients with a surgically verified pheochromocytoma. Abnormally high catecholamine excretion (epinephrine plus norepinephrine) was found in patients with pheochromocytoma compared with that in the normal subjects and the essential hypertension group. However, 3 of 31 patients with pheochromocytoma had urinary catecholamine excretion that overlapped the values in the pheochromocytoma-suspect group. Both urinary NM and M excretion also were elevated in patients with pheochromocytoma, but in 4 of 31 patients with pheochromocytoma urinary M excretion was within the range found in 1 or more of the other groups. Total M (NM plus M) excretion of more than 5485 nmol/day (as NM) was found in all patients with pheochromocytoma, and all patients had values that were higher than the highest values in the normal subjects or the patients with no evidence of pheochromocytoma. To save time and simplify the diagnostic work-up of patients suspected of having a pheochromocytoma, we also determined the NM and M concentrations in randomly voided 1-h urine samples in 24 patients with pheochromocytomas, 31 patients with essential hypertension, and 16 normal subjects. Abnormally high total M excretion was found in all patients with pheochromocytomas, and there was no overlap with the values in the patients with essential hypertension or the normal subjects. We conclude that total M measurements in both 24-h and random 1-h urine samples are useful in diagnosing pheochromocytomas.

Comparison of labetalol versus enalapril as monotherapy in elderly patients with hypertension: results of 24-hour ambulatory blood pressure monitoring.

PURPOSE: This study compared the safety and efficacy of labetalol and enalapril as antihypertensive therapy for elderly patients. PATIENTS AND METHODS: A randomized, open-label, parallel controlled trial was conducted. After completing a 4-week placebo phase, 79 elderly (65 years or older) patients with an average standing diastolic blood pressure (BP) 95 mm Hg or above and 114 mm Hg or less were randomized to receive a 12-week course of either labetalol or enalapril in an open-label design. The patients' BP and heart rate were evaluated biweekly by trained observers unaware of the treatment status, and drug dosage was titrated (up to 400 mg twice a day of labetalol or 40 mg daily of enalapril) to achieve a standing diastolic BP of less than 90 mm Hg and a decrease of 10 mm Hg from baseline. Patients underwent 24-hour ambulatory BP monitoring (ABPM) at the end of the placebo phase and again after 8 weeks of active treatment. RESULTS: The treatment groups were comparable in their reduction of supine diastolic BP, with no significant differences between the two treatments. Labetalol demonstrated a significantly greater reduction (p less than 0.05) in standing diastolic BP at the end of the titration period compared to enalapril, but this difference was not significant by the end of the study period. Based on 24-hour ABPM readings, labetalol reduced mean 24-hour diastolic BP (p less than 0.05) and mean heart rate (p less than 0.05) more than enalapril. The labetalol-treated patients were significantly less often above their diastolic BP goal throughout the 24-hour ABPM period (p less than 0.01). The two treatments were equally well tolerated. CONCLUSIONS: The results indicate that labetalol and enalapril are equally effective in lowering supine diastolic BP in the elderly, but labetalol is more effective in lowering ambulatory BP and heart rate throughout the day.

Disposition of orally administered 2,2-Bis(4-hydroxyphenyl)propane (Bisphenol A) in pregnant rats and the placental transfer to fetuses.

We studied the disposition of bisphenol A (BPA) in pregnant female F344/DuCrj(Fischer) rats and its placental transfer to fetuses after a single oral administration of 1 g/kg BPA dissolved in propylene glycol. BPA in maternal blood, liver, and kidney reached maximal concentrations (14.7, 171, and 36 microg/g) 20 min after the administration and gradually decreased. The levels were 2-5% of the maximum 6 hr after the administration. The maximal concentration of BPA in fetuses (9 microg/g) was also attained 20 min after the administration. BPA levels then gradually reduced in a similar manner to maternal blood. These results suggest that the absorption and distribution of BPA in maternal organs and fetuses are extremely rapid and that the placenta does not act as a barrier to BPA.

Elevated immunoreactive endothelin levels in patients with pheochromocytoma.

Plasma immunoreactive endothelin-1 (ET-1) concentrations were measured in 44 patients with pheochromocytoma, 31 patients with essential hypertension, and 20 healthy control subjects. Plasma ET-1 concentrations in patients with pheochromocytoma were 18.2 +/- 3.2 fmol/mL (mean +/- SEM), which was significantly higher than those of essential hypertension and healthy control subjects (7.3 +/- 0.4, 7.1 +/- 0.4 fmol/mL, respectively, P < .01). Plasma ET-1 concentrations in patients with essential hypertension and control subjects were similar. In patients with pheochromocytoma, hypertensive group had higher ET-1 than normotensive group (23.0 +/- 5.5 v 12.4 +/- 2.2 fmol/mL), but the difference was not significant. In 17 patients with pheochromocytoma, the elevated plasma ET-1 concentrations (17.4 +/- 4.7 fmol/mL) returned to normal levels (7.9 +/- 0.6 fmol/mL, P < .05) after surgical resection of the tumor. ET-1 contents in the 26 tumor tissues (1.40 +/- 0.29 pmol/g) were higher than those in 7 normal adrenal medullas (0.44 +/- 0.12 pmol/g). Systolic, diastolic, and mean blood pressures were better correlated with plasma norepinephrine than ET-1 in patients with pheochromocytoma. These data indicate that pheochromocytoma might produce and secrete excessive amounts of ET-1. The hypertension in patients with pheochromocytoma is mainly catecholamine-dependent, but may be secondarily ET-1-dependent.

Altered sympathetic tone in hypertensives with angina and lowered threshold for pacing ischemia.

To determine the role of the sympathetic nervous system in myocardial ischemia with essential hypertension, plasma norepinephrine, heart rate (HR), blood pressure (BP), and the HR.BP double product at the time of silent ischemia during pacing and exercise treadmill test (ETT) were compared with basal values in 20 patients with sustained essential hypertension and stable angina, 3 to 60 days (12.6 +/- 11.6) after discontinuation of all antihypertensive and coronary vasodilator therapy. Group I (N = 6) had silent ischemia with a higher HR.BP product at ETT than at pacing (ratio = 157 +/- 10.4% [+/- SD] v a value in group II [N = 5] of 102 +/- 18.8 [P less than .01]. Group III (N = 9) had no silent ischemia at ETT or pacing. Group I v group II plasma norepinephrine levels at rest and with pacing silent ischemia were 76 +/- 37 v 138 +/- 36 pg/mL, P less than .02, and 101 +/- 50 v 230 +/- 43 pg/mL, P less than .01, respectively. In groups I and II plasma norepinephrine levels were significantly lower than those of group III. Eleven of 20 patients had ischemia on pacing or ETT. Left ventricular myocardial mass were greater (224 +/- 49 v 180 +/- 28 g, p less than .05), HR (67 +/- 13 v 76 +/- 11 beats/min, P = NS) and plasma norepinephrine levels at rest (104 +/- 47 v 241 +/- 99 pg/mL, P less than .01), pacing (160 +/- 81 v 338 +/- 94 pg/mL, P less than .01), and ETT (758 +/- 268 v 1203 +/- 611 pg/mL, P less than .05), were lower in patients with ischemia (N = 11, group II) than in patients without ischemia (N = 9, group III) on pacing or ETT. Eight patients were on reserpine prestudy; reserpine prestudy was associated with lower basal HR (63 +/- 9 v 76 +/- 12 beats/min, P less than .05) and plasma norepinephrine (106 +/- 48 v 169 +/- pg/mL, P less than .07) and greater ratio of HR.BP double product on ETT/pacing, (141 +/- 33 v 111 +/- 19, P less than .02). The sympathetic nervous tone of group I was low at baseline but there may have been raised alpha/beta-receptor responsiveness to laboratory stresses with concomitant micro/macrovascular constriction at higher oxygen demand.(ABSTRACT TRUNCATED AT 400 WORDS)

Random one-hour urine catecholamine and 4-hydroxy-3-methoxymandelic acid assays for diagnosis of pheochromocytoma.

Using randomly voided 1-h urine samples, levels of excretion of catecholamines (CA) and 4-hydroxy-3-methoxymandelic acid (vanillylmandelic acid; VMA) were determined in order to save time in and simplify the diagnostic work-up of pheochromocytoma, particularly in out-patient hypertension clinics. Twenty-nine patients with surgically verified pheochromocytoma (15 paroxysmal and 14 sustained type), 56 patients with essential hypertension (26 labile and 30 fixed type) and 14 normal volunteers were studied. Abnormally high excretion of CA and VMA was found in all patients with pheochromocytoma when compared to those with essential hypertension or to normal controls after duly considering the influence of external factors such as food and exercise. From these results, we concluded that assays of CA and VMA even in random 1-h urine samples are useful in separating patients with pheochromocytoma from those with other types of hypertension.

Toxins contained in Microcystis species of cyanobacteria (blue-green algae).

Cyclic peptide toxins were analyzed for three Microcystis species (M. aeruginosa, M. viridis and M. wesenbergii) using an ODS-silica gel cartridge and high performance liquid chromatography with ODS-silica gel. On strain of M. aeruginosa contained a high amount of microcystin (cyanoginosin) YR and a lesser amount of LR. Three toxins, microcystin-RR, -YR and -LR, were detected in two strains of M. aeruginosa and four of M. viridis. The main component of the toxins of these strains was microcystin-RR. M. wesenbergii showed no peak in the area where the three toxins were obtained in other Microcytisis species by HPLC analysis. LD50 values of the purified toxins of YR and LR were similar, while a lower toxicity was estimated for RR. This explains the relatively weak toxicity of M. viridis whose main component is microcystin-RR.

Isolation and characterization of the minor components associated with microcystins LR and RR in the cyanobacterium (blue-green algae).

Two structurally similar analogues of microcystins LR and RR, cyclic peptide hepatotoxins from Microcystis, were isolated by chromatographic methods. Although they have the same mol. wt and amino acid compositions as those of the parent toxins, they do not possess similar toxicities. Ultraviolet and 1H-NMR spectral data for both components demonstrate clear structural difference of these cyclic peptides from the parent toxins, which are probably responsible for the marked decreases in their observed toxicities.

Testicular atrophy induced by phthalic acid monoesters: effects of zinc and testosterone concentrations.

Induction of testicular atrophy by monoesters of phthalic acid were compared in male Wistar rats. Dietary administration of monobutyl (MBP), mono-iso-butyl (MIBP) and mono-2-ethylhexyl phthalate (MEHP) induced severe atrophy of the testes. Furthermore, high testosterone concentration in the testes was found in MBP- and MIBP-treated rats, whereas low zinc concentration was found in MBP-, MIBP- and MEHP-treated rats. On the other hand, in monooctyl phthalate (MOP)-treated rats, testosterone and zinc concentrations in the testes were not changed. These were similar to the results with their diesters.

Chronic toxicity studies of piperonyl butoxide in CD-1 mice: induction of hepatocellular carcinoma.

Male and female CD-1 mice (51-104 mice/group) were administered piperonyl butoxide (alpha-[2-(2-butoxyethoxy)ethoxy-4,5-methylenedioxy-2-propyltol uene) in the diet at levels of 0 (control), 0.6 and 1.2% for 52 weeks (1 year). Hepatocellular carcinomas were induced in treated groups in a dose-dependent manner. The incidences of hepatocellular carcinoma were 11.3 and 52.0% in male mice given 0.6 and 1.2% piperonyl butoxide, and 41.2% in female mice given 1.2%. Piperonyl butoxide is thus a hepatocarcinogen to mice as it is known to be to rats.

Sub-acute toxicity of piperonyl butoxide in F344 rats.

Piperonyl butoxide, alpha-[2-(2-Butoxyethoxy)ethoxy]-4,5-methylenedioxy- 2-propyltoluene, is a pesticide synergist. F344 rats of both sex were maintained on diets containing 0, 0.6, 1.2 or 2.4% of piperonyl butoxide for 13 weeks. At the end of experimental period, they were necropsied. Selected organs were weighted and serum was analyzed by clinical chemistry. In male and female rats of the 2.4%-group, body weight gains were depressed, macroscopically, hepatomegaly was marked and liver weights were significantly higher than those of the control group. In male and female rats of all treated groups, relative kidney weights were significantly increased in a dose-dependent manner. Rats of the 2.4%-group had increased levels of albumin, cholesterol, urea nitrogen and gamma-glutamyl transpeptidase. Examination of livers of the male 2.4%-group by light microscopy showed enlarged hepatocytes with glassy cytoplasm and fatty deposition. On occasion, there was coagulative necrosis of a few hepatocytes in the periportal area and oval cell proliferation. The kidney of treated rats showed atrophy of epithelium in the proximal convoluted tubules. These results indicated that toxicity of piperonyl butoxide in rats was directed primarily to the liver and kidney.

A sensitive radioimmunoassay of alpha human atrial natriuretic polypeptide using monoclonal antibody recognizing human form ring structure.

A monoclonal antibody (C351) against alpha human atrial natriuretic polypeptide (alpha hANP) recognizing human form ring structure was established and applied to a radioimmunoassay of plasma alpha hANP. The minimum detectable amount in terms of 10% radioligand displacement relative to zero dose were 0.28 fmol/tube, corresponding to 0.7 fmol/ml in plasma after extraction using Sep-Pak C18 cartridges. When the mean plasma levels at recumbent position in fasted morning were compared in 10 young (less than 30 years) and 10 elderly (greater than or equal to 50 years) healthy subjects taking normal sodium diet, it was slightly higher in the latter (3.2 +/- 0.4 vs 4.7 +/- 0.5 fmol/ml, mean +/- SE, p less than 0.05). After i.v. infusion of hypertonic saline (2.5% NaCl) at a rate of 0.24 ml/kg/min for 20 min in 6 normal subjects (26 to 35 years), it was increased from 4.1 +/- 0.4 to 5.9 +/- 0.7 fmol/ml (p less than 0.01). In 6 patients with essential hypertension (34 to 57 years), it was elevated with high salt intake, i.e. 3.3 +/- 0.3, 3.9 +/- 1.03 and 7.6 +/- 1.5 fmol/ml under 34, 170 and 340 mEq NaCl/day for 7 days, respectively. From these results, the radioimmunoassay of plasma IR-alpha hANP using MAb C351 seems to be quite suitable to detect rather small changes at low plasma concentrations and to investigate a physiological importance of alpha hANP in man.

The psychological trade-offs of goal investment.

The primary goal of this research was to investigate the possibility that being very invested in goals has psychological trade-offs. Self-report methods were used in a concurrent study with college students (Study 1) and a longitudinal study with elementary school children (Study 2). The results of both studies provided support for the hypothesis that high goal investment has psychological trade-offs. Such investment was associated with positive emotions as well as with worrying, both concurrently and longitudinally. In addition, evidence for mediational mechanisms was provided: Perceptions of accomplishment accounted for the relation between goal investment and positive emotions; the link between goal investment and worrying was mediated by predictions that failure would be upsetting. The implications of these findings for distinguishing between depressive and anxiety symptoms are discussed.

Cultural variation in the use of current life satisfaction to predict the future.

Three studies examined cultural and situational influences on the tendency for people to use their current life satisfaction to predict future life events. On the basis of the self-enhancement literature, it was predicted that either writing about a positive personal experience or reading about another's negative experience would lead European Americans to focus their attention on internal attributes and thus would lead them to use their current life satisfaction in predicting the future. Conversely, on the basis of the self-criticism literature, it was predicted that these same conditions would lead Asian Americans to focus their attention on external factors and, therefore, would decrease their likelihood of using their current life satisfaction to predict the future. Studies 1 and 2 supported these hypotheses. Study 3 showed that these patterns could be obtained by subliminally priming concepts associated with individualism and collectivism.

Complicated presentations of groin hernias.

Elective repair of simple (uncomplicated) inguinal and femoral hernias avoids incarceration and bowel obstruction (complicated presentations). To identify factors that perturb this strategy, we analyzed the records of 1,859 consecutive nonpediatric patients with groin hernias. Incarceration or bowel obstruction prompted operation in 22 of 77 (29%) women and in 15 of 34 (44%) patients with femoral hernia. Patients presenting with bowel obstruction were significantly older than those with incarceration only and/or uncomplicated presentation, and 13 of 25 (52%) required resection of necrotic bowel. Mortality was limited to five patients of advanced age with groin hernia and bowel obstruction. Four of the five patients had undergone resection of necrotic bowel. Complicated presentations of groin hernias are associated with a higher proportion of women and patients with femoral hernias. Gangrenous bowel was encountered only in those patients with groin hernia and bowel obstruction. Early diagnosis and elective repair of uncomplicated hernias should remain our strategy in patients of all ages.