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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.

Peatland fires remain a major contributor of environmental problems in Indonesia. Several studies on peat fire suppression have been conducted with multiple methods, such as quarrying, water spray, artificial rain, and foam spray. This research is focused on laboratory scaled experiments of Indonesian peat smoldering fire behaviour and suppression by a water mist system. The peat used in this work was obtained from two different locations, namely Papua and South Sumatra, Indonesia. During the suppression tests, the intensity of the water mist spray was varied by changing the distance between the nozzle and the peat surface. Meanwhile, the time periods of spray were 15 min (short period of suppression) and approximately 2 h for full suppression until the peat fire was extinguished. The peat temperature and the total mass lost during the smoldering reaction were recorded to get the burning rate ratio for each sample. The spread rate of the smoldering process was identified by the changes in the local temperatures of the peat bed. The results show that the spread rate of the smoldering combustion front was affected by particle size and permeability of peat material. The short duration of water suppression failed to extinguish the peat fires. A re-ignition phenomenon was identified due to the persistence of stored heat in the core of the peat. In addition, the total water required to fully suppress both peat fires is about 6 L/kg peat.

An experimental study was conducted to demonstrate the concept of a new sprinkler protection system using Simultaneous Monitoring, Assessment and Response Technology (SMART). Part I of this study focuses on the system design and function evaluation at the component level. The present work is Part II of the study, focusing on full-scale suppression tests to evaluate the performance of SMART sprinkler technology in protecting rack storage fires. The selected fuel was cartoned unexpanded plastic (CUP) commodity representing an intermediate level of fire hazard. The storage height increased from 3 tiers (9.1 m) to 5 tiers (10.7 m) to 7 tiers (12.2 m) in the three tests. The sprinkler activation was initiated by a smoke detector and a ceiling temperature rise threshold. The fire location was calculated as the thermal centroid based on ceiling temperatures. A group of six sprinklers, closest to the calculated fire location, was activated simultaneously. Subsequent fire development was monitored through visual observation as well as ceiling temperature data. Test results show that the SMART sprinklers can provide adequate protection for the CUP commodities stored up to 7-tiers (12.2-m) high within a rack storage under the tested conditions. The water densities used in these tests were approximately 50% of those in existing protection recommendation. These results lay the foundation for exploring potential applications of the SMART sprinklers to Highly Challenging Fires.

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.

Sodium has unusual fire hazards, including autoignition when heated in air or exposed to liquid water. Owing to limitations of existing suppression agents for sodium pool fires, suppression using liquid nitrogen (LN 2 ) is examined here. Sodium pools of 5–80 g were heated in stainless steel beakers. At about 290 °C, pool surface autoignition occurred and caused a rapid pool temperature increase. Vapor phase combustion occurred when the pools reached 320–450 °C, ultimately leading to pool temperatures up to 700 °C. For suppression tests, LN 2 delivery (at 2.7 g/s) began when the fires became fully-developed, near a pool temperature of 600 °C. Liquid nitrogen was found to be an effective suppression agent. The minimum amount of LN 2 required to suppress a fully-developed sodium pool fire was found to be about three times the initial sodium pool mass.

Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism and account for less than 2% of all pituitary adenomas. In the last years, the diagnosis has been facilitated by the routine use of ultra-sensitive TSH immunometric assays. Failure to recognise the presence of a TSHoma may result in dramatic consequences, such as improper thyroid ablation that may cause the pituitary tumour volume to further expand. The diagnosis mainly rests on dynamic testing, such as T3 suppression tests and TRH, which are useful in differentiating TSHomas from the syndromes of thyroid hormone resistance. The first therapeutical approach to TSHomas is the pituitary neurosurgery. The medical treatment of TSHomas mainly rests on the administration of somatostatin analogues, such as octreotide and lanreotide, which are effective in reducing TSH secretion in more than 90% of patients with consequent normalisation of FT4 and FT3 levels and restoration of the euthyroid state.

Quantitatively-measuring of coal dust wettability is essential for the R/D of chemical coal dust suppressants in the field of dust control with wetting-agent-added water. Analysed the causes which in present lab testing of coal dust wettability cause out-comes’ low repeat rate and poor consistency with coal dust suppression practices in fields, and investigated the influence of different briquetting pressure (from 0 to 6.5×108 Pa) on the wet behavior of coal dust as a new way to evaluate quantitatively coal dust wettability. The study shows that there is a fairly high coincidence between the coal dust wettability data measured by briquetting technique and the results gained from the lab dust suppression tests using an apparatus MCYZ.

To reevaluate the responses of thyrotropin-releasing hormone (TRH) stimulation test in baseline condition as well as after the administration of graded supraphysiological doses of liothyronine (L-T(3)) in normal subjects.To assess various parameters related to the hypothalamic-pituitary axis and peripheral tissue responses to L-T(3) in 22 normal individuals (median age: 30.5 years). Subjects were submitted to an intravenous TRH test at baseline condition and also to the oral administration of sequential and graded doses of L-T(3) (50, 100, and 200 microg/day), each given over 3 days, at an outpatient clinic. Blood samples were obtained for thyrotropin (TSH) and prolactin (PRL) at basal and then 15, 30, and 60 minutes after the TRH injection. Effects of L-T(3) administration on cholesterol, creatine kinase, retinol, ferritin, and sex hormone-binding globulin (SHBG) were also measured at basal and after the oral administration of L-T(3).TRH administration resulted in an increase of 4- to 14-fold rise in serum TSH (8.3 +/- 2.5-fold), and in a slight rise in serum PRL concentrations (3.8 +/- 1.5-fold). Administration of graded doses of triiodothyronine (T(3)) resulted in a dose-dependent suppression of TSH and PRL. Basal thyroxine-binding globulin (TBG) and cholesterol levels decreased, and ferritin and SHBG increased after L-T(3) administration, while creatine kinase and retinol did not change throughout the study. There was a positive correlation between basal TSH and TSH peak response to TRH at basal condition and after each sequential L-T(3) doses. On the other hand, TSH peak response to the TRH test did not predict cholesterol, TBG, ferritin, or SHBG values.Using the current methods on hormone and biochemical analysis, we standardized the response of many parameters to TRH stimulation test after sequential and graded T(3) suppression test in normal subjects. Our data suggest that the evaluation of the responses of the hypothalamus-pituitary axis to TRH test as well as the impact of L-T(3) on peripheral tissues were not modified by the current methods.

The clinical and endocrinological features in 106 patients (40 men, 66 women, mean age 48 +/- 14.3 years) treated between 1973 and 1993 for proven catecholamine-secreting tumours (phaeochromocytoma: n = 88, paraganglioma: n = 10, adrenal medullary hyperplasia: n = 8) were analysed. The most frequent symptoms were palpitations (68%), severe sweating (53%) and headache (42%). 10% of patients were symptom-free. 58% of patients had consistently raised blood pressure, and 20% of patients suffered paroxysmal blood pressure crises. However, 22% of patients did not have hypertension. Raised urinary catecholamines were found in more than 95% of cases; MIBG (metaiodobenzylguanidine) scintigrams were abnormal in more than 85% of cases. Patients with catecholamine-secreting tumours do not always have "classical" features. The high sensitivity of properly performed catecholamine measurement on plasma and urine has made dangerous stimulation and suppression tests obsolete.

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.

As renin and aldosterone levels vary during the menstrual cycle, and are critical criteria for interpretation of aldosterone suppression tests to confirm or exclude primary aldosteronism, outcome of testing may vary depending on the menstrual cycle phase. We assessed the effect of timing within the menstrual cycle on levels of renin, aldosterone and female sex steroids during fludrocortisone suppression testing (FST).In 22 women undergoing FST who experienced regular menstrual cycles, renin (measured as both plasma renin activity and direct renin concentration), aldosterone (mass spectrometry) and cortisol, progesterone, oestradiol, LH and FSH (immunoassay) levels were compared, relative to phase of cycle. Aldosterone levels were compared to those in age-matched males undergoing FST.Progesterone (P0·0001) and aldosterone (P = 0·006) levels were higher in nine women (after one of 10 was excluded with anovulatory cycle) studied during the luteal phase than in the 12 studied during the follicular phase. All studied during the luteal phase had positive FST, and all three with negative FST were studied during the follicular phase. There were no significant differences in other parameters measured except FSH, which was higher (P = 0·02) during the follicular phase. Aldosterone was higher (P = 0·01) in women studied in the luteal (but not follicular) phase compared to men.The menstrual cycle may affect the outcome of FST and other suppression testing used to diagnose primary aldosteronism. Larger patient numbers and preferably restudy of the same patient in both phases should clarify this and determine the optimum time in the cycle for testing.

Full-scale suppression tests and Computational Fluid Dynamics (CFD) simulations were carried out to investigate the effect of Water-based Fixed Fire Fighting Systems (WFFFS) on the effectiveness of longitudinal ventilation systems in resisting smoke backlayering in tunnels. Test results show that WFFFS enables longitudinal ventilation systems to resist smoke backlayering with a lower velocity than the critical velocity for the same size of tunnel fire. Based on data obtained from the test program and the simulation program, a design method is proposed to estimate the velocity required to resist smoke backlayering in tunnels when WFFFS is active.

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.

Background The diagnosis of disorders of growth hormone (GH) secretion is based on the measurement of GH before and after dynamic stimulation or suppression tests. Over the years, specific cut-off values have been proposed without taking account of the considerable variation in results obtained using different methods for analysing GH. Recent publications have recommended the standardization of GH assays using IS 98/574, which is calibrated in mass and units (U). The IMMULITE range of GH assays have been recalibrated using this standard. Methods We analysed 745 samples using the current and the restandardized GH assay kits. This series of samples contained 90 stimulation tests and seven suppression tests. Results The data comparing the current and restandardized assays show a similar relationship for both basal and stimulated GH values for all IMMULITE platforms. There is a negative bias by the restandardized assay above approximately 20 μg/L. A conversion can be derived from this study which would mean that patient GH results expressed in milliunits per litre of IMMULITE in-house derived standard will be approximately three-fold of that expressed in micrograms per litre of IS 98/574. Conclusion Use of IS 98/574 offers standardized reporting in microgram per litre IS 98/574. This will permit compliance with the consensus recommendations and the development of a firm evidence base for defining decision-making GH values.

The authors of this article analyze the reasons which cause outcomes' low repeat rate in ordinary lab testing of coal dust wettability. To eliminate interfering factors in evaluating coal dust wettability measurements such as the air diaphragm, the filling density of the dust in the tube and the hydrophilic property of the glass tube, the authors develop LM-3 device for briquette making of coal dust, composing the equipment of coal dust sample making together with DQ-2.5 digital stress testing machine. The relation between the wettability behavior of the coal dust briquette sample and the sample's briquetting pressure P is studied at 0~6.5t/cm2 pressure. The cold briquetting technique improves coal dust wettability measurements, its effect is validated in the lab dust suppression tests using an apparatus MCYZ.

Endocrinology studies the elaboration, secretion, transportation, and action of hormones at the clinical, cellular, and molecular levels. Hormones regulate bodily functions over relatively large distances using the bloodstream or over short distances on a cell-to-cell basis. The clinical effects of hormonal dysfunction can be classified broadly into hormonal excess or deficiency. Endocrine testing utilizes the principle that suppression tests test for hormone excess, whereas stimulation tests identify hormone deficiency. These tests are conducted on the background of varying factors that modulate hormonal secretion, so results need to be cautiously interpreted. Probability theory is helpful in this situation by increasing or decreasing the likelihood of disease presence.

The necessity of visual preschool screening for reducing the prevalence of amblyopia is widely accepted. The beneficial results of large-scale screening programs conducted in Scandinavia are reported. Screening monocular visual acuity at 3.5 to 4 years of age appears to be an excellent basis for detecting and treating amblyopia and an acceptable compromise between the pitfalls encountered in screening younger children and the cost-to-benefit ratio. In this respect, several preschoolers' visual acuity charts have been evaluated. New recently developed small-target random stereotests and binocular suppression tests have also been developed with the aim of correcting the many false negatives (anisometropic amblyopia or bilateral high ametropia) induced by the usual stereotests. Longitudinal studies demonstrate that correction of high refractive errors decreases the risk of amblyopia and does not impede emmetropization. The validity of various photoscreening and videoscreening procedures for detecting refractive errors in infants prior to the onset of strabismus or amblyopia, as well as alternatives to conventional occlusion therapy, is discussed.

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.

Numerous tests are used in clinical practice to assess the integrity of different parts of the endocrine and neuroendocrine systems. In these procedures the relationship between the inhibitory or activating effect of the diagnostic agent and the plasma concentration of the responding hormone are most often considered, without any regard to temporal aspects. As will be shown in this review, however, the time of testing represents a variable of great importance in the interpretation of the data. Furthermore, the time-related differences in the effects of the drugs used as diagnostic but also as therapeutic agents may be critical in the interpretation of both stimulation and suppression tests of endocrine and neuroendocrine functions (Touitou 1989).

This paper provides information on Chlorine Mitigation Tests, conducted at the Department of Energy, Nevada Test Site in June 1990, by Dow Chemical USA. Typical audiences include Producers and Distributors of Chlorine, and Emergency Response Personnel. A twelve minute video has been made to assist in emergency response training. Copies are available from The Chlorine Institute, Washington DC.

The capacity to produce physical dependence is an important factor in the abuse liability of the opioids, contributing both to their reinforcing efficacy and to the negative public health consequences of abuse. Validated methods for measuring the physical dependence capacity of opioids in humans are the Direct Addiction and Substitution/Suppression tests; however, both methods require that subjects be made physically dependent on morphine or on high doses of investigational drugs. New methods need to be developed. Possibilities include assessment of acute physical dependence and the modification of existing substitution test methods for use with subjects already dependent on therapeutic agents.

With the use of a 75 g oral glucose tolerance test, both insulin release (IRG) and the degree of peripheral sensitivity (SI) were evaluated simultaneously in groups with normal (NGT) and impaired (IGT) glucose tolerance as well as NIDDM. IRG was expressed as the ratio of the area under the insulin curve to that of the glucose curve above fasting levels. The peripheral glucose uptake rate (M) during the OGTT was measured as the difference between the glucose load and the increase in the amount of glucose in the glucose space during the oral glucose tolerance test (OGTT). SI was expressed as the ratio of the metabolic clearance rate (M/mean blood glucose) to log mean serum insulin. In the non-obese groups, both mean IRG and mean SI values were decreased with an increasing degree of hyperglycemia from NGT to NIDDM. Decreased mean SI values were also found in obese subjects. IGT-subjects given 3 months of diet and exercise achieved improved SI values. A non-obese NIDDM-group had higher mean IRG and mean SI values after 6 months of treatment with glipizide. The results were comparable to data obtained with more complicated techniques, such as the insulin clamp and suppression tests, and should be easy to apply on a large scale in epidemiological studies.

We attempted to adapt an RIA method for cortisol in plasma to the analysis of “free cortisol” in urine. 3H-cortisol could be effectively extracted from urine with methylene chloride, but this solvent also extracted substances other than cortisol which were measured as “cortisol” by RIA. Urine samples which had normal cortisol measured with a competitive protein-binding assay had raised values by RIA. In an attempt to obtain the “correct” urine cortisol values for the samples, we analysed the urines using 5 commerical kits. Inspection of these results confirmed that the in-house RIA method was giving falsely high results for normal subjects, but it also showed that one kit, which was available in Canada until recently, gave spuriously high results with some urines due to interference by dexamethasone which the patients had received as part of a suppression test. We suggest that kit manufacturers should thoroughly evaluate their products prior to release, and that the evaluation should include measurements on a reasonably large and varied patient population to determine appropriate reference ranges and the response to stimulation or suppression tests.

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.

Deflagration suppression is one of several means of explosion protection for process volumes. This paper presents a discussion of some of the variables which influence the final pressure obtained upon suppression of a process deflagration. In particular the discussion focuses on suppression of the deflagrations of fast burning dusts, i.e. dusts with high Kst values. The discussion is amplified using recently obtained data from deflagration and suppression tests on three flammable dusts representing the St-2 and St-3 deflagration classes. It is shown that the relationship between post-suppression pressure and Kst value is not always as expected. The underlying reason for this result relates to differences in the burning characteristics of the subject dusts in the relevant stages of the deflagration.

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.

Summary. A group of 39 Nigerian infants and pre-school children with protein-energy malnutrition (PEM) have been studied. Red cell folate levels were within the range observed in 19 age-matched healthy Nigerian children. Serum vitamin B12 levels were either normal or raised. Deoxyuridine (dU) suppression tests were performed on the bone marrow cells of 30 of the patients and were abnormal in 13. It is proposed that the abnormal dU-suppressed values were not caused by vitamin B12 or folate deficiency and were probably a consequence of the protein deficiency. A few megaloblasts and several giant metamyelocytes were found in four of the cases of PEM; the remaining 35 cases had normoblastic erythropoiesis, sometimes with small to moderate numbers of giant metamyelocytes. All four marrow samples containing megaloblasts gave abnormal dU-suppressed values. However, in the marrows showing normoblastic erythropoiesis there was no correlation between the presence or absence of giant metamyelocytes and the dU-suppressed value.

A study of antithyroid drug (ATD) therapy with a mean follow-up period of 10 years (range 2-25) in 434 patients with Graves' disease has been made by linking hospital records with those of a central follow-up register. The majority (89%) were treated with carbimazole and 87% received combined therapy with triiodothyronine (T3) (73%) or thyroxine (T4) (14%). Sixty-one per cent were assessed for T3 suppression tests on completion of treatment, of whom 61% (95% CL, 55-67%) suppressed. The overall 5-year cumulative proportion developing recurrent hyperthyroidism was 54-62% with rates of 26-44% in suppressed patients and 65-79% in those not suppressed. In unsuppressed patients, most (72%) of the recurrences occurred within 1 year with only an additional 10% predicted up to 10 years. In suppressed patients 30% of recurrences occurred in the first year, 60% between 1 and 5 years and a further 10% between 5 and 10 years. Suppression with T3 is probably the best and cheapest predictor of outcome but has an accuracy of only 70% for both positive and negative tests which limits its usefulness in planning long-term follow-up and surveillance. A standard format should be adopted for the analysis and reporting of follow-up studies, based on actuarial methods of estimating the cumulative proportion with recurrences or other events, to facilitate comparisons between different centres.

Patients with endocrine orbitopathy (Graves' disease) are often euthyroid when seen, up to half may have normal Werner suppression tests, and frequently have no known history of thyroid disease. Ultrasonography. especially using quantitative A-scan techniques. provides the simplest and most reliable means of diagnosing endocrine orbitopathy. Accurate and reproducible measurements can be made of rectus muscle thicknesses, as well as of the size of the subdural perineural space about the optic nerve. One hundred consecutive patients in whom the diagnosis of endocrine orbitopathy was made by diagnostic ophthalmic ultrasonography are herein considered.While the clinical presentation may be unilateral, ultrasonography will demonstrate bilateral abnormalities (and, in fact. this is a necessary condition for making the diagnosis). These may occasionally be extremely subtle. perhaps consisting of no more than an otherwise inexplicable increase in the subdural perineural space about the retrobulbar optic nerves; w...

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.

SummaryA total of 132 triiodothyronine suppression tests were performed using 100 μg of T3 for 7 days. Radioiodine uptake at four hours, serum thyroxine [T4(D)], T3 binding coefficient [RT3U ratio] and free thyroxine index [T4-RT3 index] were estimated before and after a course of triiodothyronine.T4(D) decreased significantly in only 38.4% of T3 suppression tests assessed as positive by the decrease in radioiodine uptake; it did not change or increased significantly in 84.7% of tests negative by radioiodine uptake.RT3U ratio showed little change in all groups. The changes in T4-RT3 index were similar to those of T4(D).The correlation of changes in T4(D) with 4 hour radioiodine uptake is poor (r = 0.34).Agreement between changes in radioiodine uptake and T4(D) was observed only in 54% of tests; between changes in uptake and T4-RT3 index in 69.4%.Estimation of serum thyroxine or free thyroxine index in the T3 suppression test cannot substitute for the radioiodine uptake for reasons which are discussed.

The diagnostic radioactive iodine and T.I.T. suppression tests as practised in this department are described. The T.I.T. suppression test has proved of value in cases which give anomalous results in the routine radioactive iodine studies. The results of this test in such cases are given. Some possible causes of anomalous results are briefly discussed.

Triiodothyronine suppression tests with estimation of 131I uptake 20 min after i.v. injection were performed at 6-monthly intervals on 69 thyrotoxic patients treated with Carbimazol and L-triiodothyronine for 18 months. 29 patients relapsed while 40 remained euthyroid. The prognostical value of the suppression test was evaluated statistically. Uptakes under 8 per cent after 6 months' treatment suggest the patient will not relapse (prognostic sensitivity 0.8). Uptakes over 8 per cent do not select patients who relapse (prognostic specificity 0.4–0.5).

A patient with the testicular feminization syndrome underwent adrenal stimulation and suppression tests, as well as stimulation with purified human FSH prior to gonadectomy. Estrogen excretion was depressed by dexamethasone and clevated by ACTH. Purified FSH had no effect on estrogen excretion levels. After gonadectomy, preoperative urinary estrogen excretion levels were found, although the subject was not treated with exogenous steroids. Breast size, vaginal cornification, voice, and hair distribution did not change. Stimulation postoperatively with chorionic gonadotropin did not alter estrogen excretion. These data indicate that the estrogens formed in this patient are at least partly of adrenal origin.

SUMMARY Adrenocortical suppression tests, based on the fall in urinary 17-hydroxy-corticosteroid excretion during the oral administration of dexamethasone, were found to be of value in the diagnosis of Cushing's syndrome, but less useful in differentiating bilateral adrenal hyperplasia from adrenal tumour. Such tests have the disadvantage of requiring accurate urine collections and of taking several days to perform. A test is described, based on the decrease in plasma cortisol concentration during i.v. infusion of dexamethasone at a rate of 1 mg./hr. The results obtained in 12 patients with Cushing's syndrome and bilateral adrenal hyperplasia differed from those found in control subjects in that there was a delay between the start of the infusion and the fall of plasma cortisol, and the rate of fall was less rapid. The values found after 180 min., expressed either as μg./100 ml. or as a percentage of the resting level, differed significantly (P < 0·001) in the two groups. The test proved valuable as an aid to the diagnosis of Cushing's syndrome, was easy to perform, and could be completed in 3 hr. In some patients with Cushing's syndrome, the administration of synthetic glucocorticoids appeared to result in an increased urinary steroid excretion. A transient increase in plasma cortisol levels was also observed in some of these patients during the early period of dexamethasone infusion. It is thought that this finding reflects an alteration in steroid metabolism induced by dexamethasone and fluorocortisol.

Fourteen patients with Cushing's syndrome and 10 patients with a predominantly virilizing syndrome were studied and compared to a series of healthy subjects. Measurements ofurinary corticosteroids, 17-ketosteroids and aldosterone and of plasma corticosteroids were carried out while the patients were untreated, while they were receiving intramuscularinjections of ACTH over a 48-hour period, and following the withdrawal of ACTH. The results indicate that, after ACTH stimulation, the return of adrenocortical function to prestimulation levels is often delayed in patients with adrenocortical hyperfunction due to hyperplasia, as compared to normal subjects. This effect is best demonstrated by the 48-hourvalue of the plasma corticosteroids. Five-day suppression tests with 9α-fluorohydrocortisone were carried out in 10 patients. A rough correlation was observed between the responsiveness of a patient to this drug and the responsiveness of the same patient to ACTH. Initial observations with oxylone in 2 p...

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.