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Rationale: The utility of fractional exhaled nitric oxide (FENO) suppression (FeNOSuppT) to identify non-adherence to inhaled corticosteroid (ICS) treatment has previously been reported, but whether it can predict clinical outcome remains unclear. Objectives: We examined the utility of FeNOSuppT in prediction of progression to biologic agents or discharge from specialist care. Methods: FeNOSuppT was measured at home using remote monitoring technology of inhaler use alongside daily FENO measurement over 7 days. Long-term clinical outcomes in terms of progression to biologic agent or discharge from specialist care were compared for non-suppressors and suppressors. Measurements and main results: Of the 162 subjects, 135 successfully completed the test with 81 (60%) positive FENO suppression tests. Subjects with a negative FeNOSuppT were more likely to proceed to biologic therapy (39 of 54 patients, 72%) compared to those with a positive FeNOSuppT (35 of 81 patients, 43%, p=0.001). In subjects with a positive FeNOSuppT, predictors of progression to biologic therapy included higher dose of maintenance steroid at initial assessment and prior intensive care unit admission. These subjects had a significant rise in FENO between post-suppression test and follow-up (median, 33 (IQR 25–55) versus 71 (IQR 24–114); p=0.009), which was not explained by altered corticosteroid dose. Conclusions: A negative FeNOSuppT correlates with progression to biologic therapy. A positive FeNOSuppT, with subsequent maintenance of “optimised” FENO, predicts a subgroup of patients in whom asthma control is preserved with adherence to high-dose ICS/long-acting β2 agonist and who can be discharged from specialist care., A positive FENO suppression test can identify non-adherence. Maintenance of “optimised” FENO by sustained adherence to inhaled therapy predicts patients who are likely to maintain control with high-dose inhaled therapy without the need for biologics. https://bit.ly/3cRpQ5B

The purpose of the study is to evaluate the positive predictive value of the combined pituitary dynamic enhanced MRI (dMRI) and high-dose dexamethasone suppression tests (HDDST) in the diagnosis of Cushing’s disease (CD) bypassing bilateral inferior petrosal sinus sampling (BIPSS). A total of 118 patients with Cushing’s syndrome (CS), who underwent pituitary dMRI, HDDST and BIPSS were included. Positive predictive value of pituitary dMRI, HDDST, BIPSS and the combined test were calculated and tumor lateralization accuracy was further analyzed. The positive predictive value of the combined pituitary dMRI and HDDST was 98.6%, higher than that of BIPSS. There were 96.8% of patients, who had either negative findings in pituitary dMRI or HDDST, showing centralizing BIPSS results. For tumor lateralization, the accuracy by pituitary dMRI was 88.6%, whereas BIPSS was 57.5%. Therefore, CS patients with both positive findings in pituitary dMRI and HDDST need no further invasive evaluation to establish the definite diagnosis of CD. BIPSS will improve the diagnostic accuracy when negative findings were found in either pituitary dMRI or HDDST.

A case of a 50-year-old woman who was referred for the evaluation of possible ACTH-dependent Cushing’s syndrome (CS) is described. The localisation of ACTH-dependent CS remains difficult despite many advances in diagnostic approaches. No single test can accurately determine the location of ACTH excess and therefore a combination of non-invasive imaging, stimulation and suppression tests are advised. The recent advances, current utility and pitfalls of each of these tests are reviewed. If non-invasive tests fail to confidently localise the source of ACTH excess, inferior petrosal sinus sampling (IPSS) should follow. Recent advances improving the diagnostic accuracy of IPSS, such as DDAVP stimulation and simultaneous sampling for prolactin is discussed. Where ectopic ACTH production is suspected, newer nuclear medicine techniques, such as somatostatin receptor imaging that recently became available in South Africa, can be utilised. The role of nuclear medicine imaging in identifying ectopic ACTH production is discussed briefly.Keywords: ACTH, cushing’s disease, pituitary

Dust explosions continue to pose a serious threat to the process industries handling combustible powders. According to a review carried out by the Chemical Safety Board (CSB) in 2006, 281 dust explosions were reported between 1980 and 2005 in the USA, killing 119 workers and injuring 718. Metal dusts were involved in 20% of these incidents. Metal dust deflagrations have also been regularly reported in Europe, China and Japan. The term “metal dusts” encompasses a large family of materials with diverse ignitability and explosibility properties. Compared to organic fuels, metal dusts such as aluminum or magnesium exhibit higher flame temperature (T f ), maximum explosion pressure (P max ), deflagration index (K St ), and flame speed (S f ), making mitigation more challenging. However, technological advances have increased the efficiency of active explosion protection systems drastically, so the mitigation of metal dust deflagrations has now become possible. This paper provides an overview of metal dust deflagration suppression tests. Recent experiments performed in a 4.4 m 3 vessel have shown that aluminum dust deflagrations can be effectively suppressed at a large scale. It further demonstrates that metal dust deflagrations can be managed safely if the hazard is well understood.

In spite of the presence of definitive diagnostic criteria to diagnose Cushing syndrome diagnosis may become challenging. We report a young female with mild clinical features of Cushing syndrome, who had nonsuppressible oral dexamethasone suppression tests; also she had a suspicious pituitary lesion. She underwent pituitary surgery and a pituitary microadenoma (non-ACTH staining) was removed. Now she had come to us with similar complaints to those before. Again she had nonsuppressible oral dexamethasone suppression tests. As the diurnal variation of serum and salivary cortisol was maintained and urinary free cortisol was normal, further evaluation with IV dexamethasone suppression test was performed which clearly ruled out Cushing syndrome. The patient was not on any medicines known to alter dexamethasone metabolism. Fat malabsorption was also ruled out using appropriate tests. The reason for this discrepancy is thought to be altered (increased) metabolism of dexamethasone in this patient as it is widely variable in the general population.

Amaç: Bu çalışmanın amacı duyusal modülasyon bozukluğuna yol açan migren hastalığı olan kişilerde işitme sistemi reşeksi ölçümünde kullanılan bir test olan kontralateral otoakustik süpresyon testinin sonuçlarının değerlendirilmesidir.Yöntem: Çalışmaya nöroloji polikliniğine başvuran, Uluslararası Başağrısı Derneği’nin 2004 yılı kriterlerine göre migren tanısı alan ve vestibüler şikayeti olmayan gönüllü migren hastaları ve sağlıklı gönüllüler dahil edildi. Bütün gönüllülere tam otolojik muayene, saf ses odyometri testi yapıldı. Bilateral otoakustik emisyon yanıtı alınan 30 gönüllü migren hastası ve karşılaştırma için yaş ve cinsiyet özellikleri gönüllü hasta grubuna benzeyen 30 sağlıklı gönüllü çalışmaya dahil edildi. Çalışmaya dahil edilen gönüllülere kontralateral 50 dB SPL geniş bant gürültü ile maske yapılarak 65 dB click uyaran ile maskeli ve maskesiz otoakustik emisyon ölçümleri yapıldı. Her iki gruptan elde edilen veriler karşılaştırıldı.Bulgular: Sağlıklı gönüllülerin değerlendirilen 60 kulağının 40’ında (%67) süpresyon testi pozitif olarak tespit edilirken migren hastalarının değerlendirilen 60 kulağından 30’unda (%50) süpresyon testi pozitif olarak tespit edildi. Fakat süpresyon pozitişiği oranlarında ve süpresyon emisyon değerlerinde istatistiksel olarak anlamlı bir fark izlenmedi. İki grup arasında istatistiksel olarak anlamlı bir fark olmasa da migrenli grupta kontralateral supresyon cevaplarında azalma izlendi.Sonuç: Vestibüler şikayeti olmayan migren hastalarında normal kişilerle karşılaştırıldığında istatistiksel olarak anlamlı olmasa da kontralateral süpresyon cevaplarında bir azalma izlenmektedir. Daha büyük seri içeren yeni çalışmalar ile kontralateral otoakustik emisyon testi vestibüler şikayeti olmayan migren hastalarında odyovestibüler şikayetlerin erken tanısında kullanabileceği kanaatindeyiz.Anahtar sözcükler: Kontralateral süpresyon testi, MOC reşeksi, non-vestibüler migren, otoakustik emisyon., Objective: Our aim was to investigate contralateral suppression ofotoacoustic emission for the evaluation of auditory reflex in patientswith migraine which is a disease that may cause dysfunction of sensorial modulation.Methods: Voluntary migraine patients without vestibular symptomswho consulted to Neurology Clinic, and diagnosed according to theIHS 2004 criteria, and healthy volunteers were included in the study.All volunteers underwent complete otorhinolaryngologic and puretone audiometric examinations. Thirty voluntary migraine patients withbilateral otoacoustic emission measurements, and 30 healthy volunteersmatched in terms of age and sex were included in the study. Otoacousticemission measurements were obtained with 65 dB SPL click stimuluswith and without mask by masking with contralateral 50 dB SPL broadband noise. Responses were compared between two groups.Results: Positive result was obtained in suppression tests in 40 of 60(67%) ears of healthy volunteers and in 30 of 60 (50%) ears ofmigraine patients. However, there was no statistically significant difference between groups regarding positive suppression frequency andsuppression values. Even though a statistically significant differencebetween migraine patients without vestibular involvement and control group was not seen, there was a decrease in contralateral suppression responses in the migraine group.Conclusion: Although it is statistically insignificant, we have demonstrated that migraine patients without vestibular symptoms showed a decreasein the suppression values compared to the healthy volunteers. We believethat in new studies with larger series, contralateral otoacoustic emissionsuppression test can be used as an early tool to diagnose audiovestibularsymptoms in migraine patients without any vestibular involvement.

This study deals with the fire suppression capability and cooling characteristics required to prevent spontaneous re-ignition in a power transformer room. A water mist system was considered as a possible alternative to a gaseous suppression system. High- and lowpressure water mist systems were examined. The power transformer examined in this study occupied about 7% of a 10 m × 10 m × 10 m test room. Full-scale suppression tests were performed for six different fire scenarios: two spray fires, three pool fires, and one cascade fire. Three reduced-scale models were used to estimate the cooling characteristics required for the power transformer and to calculate the necessary discharge time for the water mist to prevent spontaneous re-ignition. The fire suppression test results demonstrated that the high-pressure system was superior to the low-pressure system, especially considering oxygen depletion and the ambient temperature distribution. In the cooling tests, the discharge time required to prevent spontaneous reignition was estimated to be about 12 h for both the high- and low-pressure systems.

According to the diagnostic criteria for adrenal preclinical Cushing's syndrome (PreCS) established by a group headed by the Ministry of Health, Labor and Welfare (MHLW), low- and high-dose dexamethasone suppression tests (DSTs) must be performed to prove autonomous cortisol secretion, i.e., > or =3 microg/dL serum cortisol following 1-mg DST administration, and > or =1 microg/dL serum cortisol following 8-mg DST administration. However, discrepancies have been documented in the results of low-and high-dose DSTs. We therefore investigated the validity of the DST for diagnosing PreCS by performing 1-mg and 8-mg DSTs in 39 patients with adrenal incidentaloma, but no characteristic Cushingoid symptoms. In about half of these patients (20/39, 51.3%), high-dose DST was positive but low-dose was negative, and one or more of the other abnormalities of hypothalamus-pituitary-adrenal axis dysfunction was seen in 75% of these patients. Furthermore, no significant difference in incidence of glucose intolerance and hypertension was noted in patients with positive high-dose DST and negative low-dose DST compared with patients with positive low- and high-dose DST. Under the current MHLW diagnostic criteria, patients with positive high-dose DST and negative low-dose DST are not diagnosed with PreCS, but some of these patients should be. Discrepancies in the results of low- and high-dose DSTs appear attributable to the current cutoff values, and further investigations are necessary to resolve these discrepancies.

The aim of this study is to review the experience of the clonidine suppression test in a regional endocrine centre and to compare the diagnostic sensitivity and specificity using various previous published criteria. The design used is retrospective study. The subjects include 56 patients in whom clonidine suppression tests had been performed from 1995 to 2000: 15 with phaeochromocytoma and 41 patients in whom the diagnosis was excluded using a combination of biochemical testing, abdominal computed tomography scanning and clinical follow-up. Plasma catecholamines were measured by high pressure liquid chromatography on basal samples and at hourly intervals for 3 h after the administration of clonidine 300 μg orally and the following diagnostic criteria were applied: plasma noradrenaline+adrenaline2.96 nmol l(-1) at 3 h post-clonidine or a baseline plasma adrenaline plus noradrenaline11.82 nmol l(-1); plasma noradrenaline2.96 nmol l(-1) at 3 h post-clonidine and plasma noradrenaline2.96 nmol l(-1) and50% fall in noradrenaline at 3 h post-clonidine. The results obtained is that mean plasma noradrenaline plus adrenaline fell across the test in 40/41 patients in the non-phaeochromocytoma patients and was lowest at 3 h (basal 2.28 ± 0.14 vs 1.36 ± 0.11 nmol l(-1), P0.001). In the phaeochromocytoma group, clonidine had a variable effect on adrenaline plus noradrenaline levels with increases in 7/15. Using an abnormal result as a 3 h level of noradrenaline plus adrenaline2.96 mmol l(-1) gave a sensitivity of 93% and specificity of 95%. When a 3 h noradrenaline2.96 mmol l(-1) was used, sensitivity was 87% and specificity 95%. Using the former criteria, noradrenaline plus adrenaline2.96 mmol l(-1), 1/15 in the phaeochromocytoma group had a normal result after clonidine suppression testing. Two of 41 in the non-phaeochromocytoma group had a false-positive result. Under carefully controlled conditions, the clonidine suppression test is well tolerated, safe and accurate for use in the investigation of patients with suspected phaeochromocytoma.

Water mist suppression tests for glass-reinforced polyester (GRP) panels were conducted in ISO 9705 Room. GRP panels covered part of the room and a wood crib fire was used as fire source to ignite GRP fire. A four-nozzle water mist suppression equipment was used inside test room on the time of flashover. Heat release rate of the combustion inside the room, room temperature, surface temperature of GRP panels, total heat flux to wall, ceiling and floor in specific positions were measured. Gas concentration of O2, CO, and CO2 was also measured in the corner of the room at two different levels. A thermal image video was used to record the suppression procedure inside room. Test results show that the water mist system is efficient in suppressing the flashover of GRP fire and cooling the room within short time.

Several N-substituted C-normorphinans (VIII and IX) were synthesized and tested for their analgetic and narcotic antagonist activities and physical dependence capacity. Treatment of N-formyl- octahydro-2-pyrindine (IIIc) with polyphosphoric acid readily gave N-formyl-C-normorphinan (IV). The N-nor bases (V and VII) obtained from IV were converted to VIII and IX. The N-methyl derivative (I), which was previously reported to be inactive by Haffner's method, exhibited potent analgetic activity by the hot plate method and the AcOH-induced writhing test. Compounds VIII and IX showed pharmacological properties similar to those of N-substituted morphinans and exhibited agonist (analgetic) and/or narcotic antagonist activities. The C-nor analogue (IXa) of cyclorphan (IIc) exhibited potent analgetic and antagonist activities with no physical dependence capacity in the single-dose suppression tests both in rats and monkeys.

Accurate localization of the source of androgen hypersecretion is critical to the appropriate surgical or medical management of women with virilization. Seven patients with virilization and hyperandrogenism of various causes were evaluated with the use of sequential studies: (1) testosterone stimulation and suppression tests; (2) computerized tomography (CT); (3) selective venous catheterization; and (4) 131 I-iodomethyl-norcholesterol (NP-59) scintigraphy. Comparison of the diagnostic accuracies of these localization studies with the ultimate diagnoses in this group of virilized women showed that: (1) endocrinologic suppression/stimulation studies are of limited value in tumor localization and helpful only in patients with steroidogenic enzyme deficiencies; (2) both selective catheterization and CT scanning may provide spurious localization data; and (3) NP-59 scintigraphy, by depicting both the anatomic localization and functional androgen hypersecretion, may provide the most significant localization data in the evaluation of patients with virilizing syndromes.

This is a report of ectopic thyroid tissue in the neck, associated with a nodular colloid goiter, which recurred at least three times, beginning at age 24 years, in a woman in 12 years. The ectopic tissue appeared histologically benign and was identical to that found in the thyroid gland. Scintiscans of the neck and thyroid suppression tests showed that the tissue was initially unsuppressible and presumably autonomous in its function. Our conclusion is that the most reasonable explanation for this phenomenon is the intraoperative transmission of thyroid cells, probably benign and autonomous in function, to other sites in the neck.

A T4 suppression test involving 24-h thyroidal 131I uptake was carried out on patients with Graves' disease during therapy with an antithyroid drug. Thirty-three patients received propylthiouracil (PTU) for at least 1 year. Each patient was given 75 micrograms L-T3 daily for 8 days in conjunction with PTU (50 mg/day) at the time of the experiment and then the 24-h thyroidal 131I uptake (post T3 uptake was measured). Twenty-two patients had normal levels of serum T3 and T4-I before L-T3 administration and were divided into 2 groups, positive T3 suppression (post T3 uptake less than or equal to 35%, group I) and negative T3 suppression (post T3 uptake greater than 35%, group II). Eleven patients showed elevated serum T3 or T4-I concentrations before L-T3 administration (group III). The T4 suppression test was then performed on the same patients. Each patient was given 300 micrograms L-T4 daily for 8 days in conjunction with PTU and the 24-h thyroidal 131I uptake (post T4 uptake) was measured. Some patients receiving PTU (50 mg/day) were switched to MMI (5 mg/day) and the T4 suppression test was done one month later. A significant correlation between the two suppression tests during PTU therapy was observed (r = 0.961, p less than 0.01). None of the patients complained of side effects during the T4 suppression test. The mean post T4 uptake in group I was 18.8 +/- 3.3% during PTU therapy and 5.4 +/- 1.3% during MMI therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

TRH and T3 suppression tests were performed on patients (124 cases) with Graves' disease who underwent radiation therapy. TRH test was performed at 4-6 months (Group I), 6-12 months (Group II), 12-24 months (Group III) and 24-50 months (Group IV) after final radiation therapy, and T3 suppression test was performed just after each TRH test. The response to TRH test was defined as positive when the basal TSH value was less than 2.0 muU/ml and the peak value was more than 6.2 muU/ml following TRH (500 mug) injection. T3 suppression test was performed by measuring the 24-hr thyroidal uptake of radioiodine after daily administration of 75 mug of T3 for 8 days. The response was defined as positive when the value for 24-hr uptake after T3 administration was less than half of the control value. The results were as follows; 1) Among 124 patients in Group I to IV who were clinically euthyroid and whose T3-RU and T4 values were normal, compared with other groups, Group IV (2-4.2Y) showed a significantly higher percentage of positive responses to both TRH and T3 suppression tests. However, among 49 of 124 patients whose T3 was also normal, there were no significant differences between the groups. 2) The value of triiodothyronine was above the normal range in many cases up to 2 years after radiation therapy (in Group I, II, III). 3) There were no significant differences in the percentage of hyperresponses between any of the four groups. Half of the patients who showed positive responses to TRH test showed exaggerated responses. 4) In all cases when the responses to TRH and T3 suppression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 supression tests changed from negative to positive, thyroxine and triiodothyronine concentrations must be within the normal range. In particular, the major determinant seems to be the value of triiodothyronine. 5) As in more than 30% of cases TRH and T3 suppression tests remained negative even though their T3-RU, T4, T3, values became normal after radiation therapy, the regulation of hypothalamo-hypophyseal thyroid axis do not always return to normal even though circulating thyroidal hormone level return to an euthyroid state.

Because unexplained megaloblastic erythroid maturation occurs in patients with primary refractory sideroblastic anemia (PRSA), deoxyuridine (dU) suppression tests using125 I-UdR were performed on bone marrow from five patients with PRSA. All patients had megaloblastic alterations in the marrow erythroid precursors (with normal serum folate and B12 levels) and numerous ringed sideroblasts, and most had marrow iron overload. Results of the dU suppression tests were normal in all five, both with and without incubation with pharmacologic amounts of folate, B12, and pyridoxal phosphate with or without 1-serine. Despite occasional hematologic improvement subsequent to folate, pyridoxine, or pyridoxal phosphate (PLP) administration in some patients with PRSA, normal dU suppression implies that in our group the availability of B12 and folate (and possibly PLP) was not limiting in the utilization of folate for DNA-thymine synthesis. The marrow erythroid maturation defect remains unexplained.

Deoxyuridine (dU) suppression tests have been performed on virtually all marrow samples aspirated at this hospital over the past 12 months. Of the 110 samples studied 26 gave abnormal results, and these 26 samples came from patients deficient in either vitamin B(12) or folate. The dU suppression test was found to be of particular value in the diagnosis of vitamin B(12) or folate deficiency in non-anaemic patients with macrocytosis and equivocal changes in marrow morphology and in patients in whom the serum vitamin B(12) or red cell folate levels were within the normal range.

In order to examine the dexamethasone suppressibility of plasma pregnenolone, 9 a.m. and overnight suppression tests were performed in normal adult subjects and plasma pregnenolone levels were radioimmunoassayed. The results were as follows: 1) In the 9 a.m. test, plasma pregnenolone was suppressed to the lowest level at the time between 30 min and 2 hr after dexamethasone; 2) there was no significant difference in dexamethasone suppressibility of plasma pregnenolone between the 9 a.m. test and overnight test; 3) there was no significant difference from each other among the plasma pregnenolone levels after dexamethasone administration (0.5 mg to 3 mg) in both tests; 4) after dexamethasone administration, plasma pregnenolone was not suppressed below 40% of the basal level in both tests; 5) discussions were made about the results, comparing with those of the suppressibility of cortisol which were previously reported from this laboratory.

A thyroid suppression test is suggested which relies on the change in concentration of serum thyroxine as the index of thyroid response to the administration of triiodothyronine. The test has been carried out in 16 healthy volunteers and in 27 patients referred for routine suppression tests. This index appears to be sensitive and safe and results in a reduction in the required dosage of triiodothyronine. The test can be carried out in fewer patient-visits than the commonly used suppression test; moreover, in remote areas the patient need not attend the specialist centre because the course of triiodothyronine can be given (and the serum samples obtained) locally, the samples then being sent to the appropriate laboratory for assay.

Two cases of parathyroid tumours occurring in unusual situations are described. Such cases may cause difficulty in both the diagnosis and the surgical treatment of hyperparathyroidism. The cases described illustrate the importance of a definitive aetiological diagnosis in hypercalcaemia, if appropriate surgery is to be performed. The value of discriminant function analysis and hydrocortisone suppression tests are discussed.