Higher-order suppression in diffraction-grating monochromators using thin films

Although a continuously tuneable source of photons is a very desirable feature of synchrotron radiation it has one main drawback: the contamination of the photon beam by higher-order diffracted light. Several elements have absorption edges which lie between 10 and 200 eV, a range prone to high second- and third-order content in XUV monochromators. They can, therefore, be used as transmission filters to reduce this higher-order content. This paper describes the use of thin filters to reduce the higher-order content in diffraction-grating monochromators. Their suppression efficiency, transmission and ageing have been characterized using photoelectron spectroscopy and compared with calculated values. The effect of oxide contamination on their performance has been assessed. Filters are now installed on eight XUV beamlines and have been in routine use for several years.

Tolcapone in stable Parkinson's disease: efficacy and safety of long-term treatment. Tolcapone Stable Study Group

In this double-blind, placebo-controlled trial, we investigated the effect of the catechol-O-methyltransferase inhibitor tolcapone 100 or 200 mg three times daily on activities of daily living and motor function in 298 patients with parkinsonism receiving levodopa but without motor fluctuations. At 6 months, both dosages of tolcapone produced significant reductions in the Unified Parkinson's Disease Rating Scale scores for activities of daily living (Subscale II) and motor function (Subscale III) and in the total score for Subscales I to III. These improvements were maintained up to the 12-month assessment. At 6 months, both tolcapone groups had changes in levodopa dosage that were significantly different from placebo: the tolcapone groups had decreases in mean total daily dose of levodopa, whereas the placebo group had a mean increase. Tolcapone was well tolerated. The principal adverse events were levodopa-related, but these were generally mild or moderate. Diarrhea was the most frequent nondopaminergic adverse event. Tolcapone appears to be beneficial in the treatment of patients with parkinsonism who have not yet developed motor fluctuations.

Protocol for accurate assessment of ABPI in patients with leg ulcers

Ankle brachial pressure index (ABPI) calculations are performed by nurses in the assessment of patients with leg ulceration. The measurement of pressure in one arm alone can result in inaccuracy which may be clinically significant. Two vascular nurse technologists performed ABPI measurements on 250 patients with 487 lower limbs. Community nurses replicated the study on 71 patients, assessing 123 lower limbs. The study shows that 22% of patients in the vascular laboratory and 20% in the community had a difference in brachial pressures of > or = 15 mmHg, indicating the presence of arch vessel or upper limb arterial disease. Furthermore, 6% of patients in the laboratory and 2% in the community demonstrated that the difference in brachial pressures affected the ABPI calculation around the value of 0.8, thus potentially influencing their clinical management. ABPI measurements should be performed, taking both brachial pressures for optimum results.

The CDK7-cycH-p36 complex of transcription factor IIH phosphorylates p53, enhancing its sequence-specific DNA binding activity in vitro

Phosphorylation is believed to be one of the mechanisms by which p53 becomes activated or stabilized in response to cellular stress. Previously, p53 was shown to interact with three components of transcription factor IIH (TFIIH): excision repair cross-complementing types 2 and 3 (ERCC2 and ERCC3) and p62. This communication demonstrates that p53 is phosphorylated by the TFIIH-associated kinase in vitro. The phosphorylation was found to be catalyzed by the highly purified kinase components of TFIIH, the CDK7-cycH-p36 trimeric complex. The phosphorylation sites were mapped to the C-terminal amino acids located between residues 311 and 393. Serines 371, 376, 378, and 392 may be the potential sites for this kinase. Phosphorylation of p53 by this kinase complex enhanced the ability of p53 to bind to the sequence-specific p53-responsive DNA element as shown by gel mobility shift assays. These results suggest that the CDK7-cycH-p36 trimeric complex of TFIIH may play a role in regulating p53 functions in cells.

Tolcapone in stable Parkinson's disease: efficacy and safety of long-term treatment. The Tolcapone Stable Study Group

In this double-blind, placebo-controlled trial, we investigated the effect of the catechol-O-methyltransferase inhibitor tolcapone 100 or 200 mg three times daily on activities of daily living and motor function in 298 patients with parkinsonism receiving levodopa but without motor fluctuations. At 6 months, both dosages of tolcapone produced significant reductions in the Unified Parkinson's Disease Rating Scale scores for activities of daily living (Subscale II) and motor function (Subscale III) and in the total score for Subscales I to III. These improvements were maintained up to the 12-month assessment. At 6 months, both tolcapone groups had changes in levodopa dosage that were significantly different from placebo: the tolcapone groups had decreases in mean total daily dose of levodopa, whereas the placebo group had a mean increase. Tolcapone was well tolerated. The principal adverse events were levodopa-related, but these were generally mild or moderate. Diarrhea was the most frequent nondopaminergic adverse event. Tolcapone appears to be beneficial in the treatment of patients with parkinsonism who have not yet developed motor fluctuations.

HPA axis dysfunction in depression: correlation with monoamine system abnormalities

Abnormality of the hypothalamic-pituitary-adrenal (HPA) axis has been one of the most consistently demonstrated biological markers of depressive disorder. It has also been proposed that abnormality of monoamine function plays a role in the pathogenesis of the disorder. In order to examine the interrelationships of the HPA axis with the dopaminergic, noradrenergic, and serotoninergic systems, we studied, in 52 medication-free inpatients with DSM-IV nonpsychotic major depressive disorder, the relationship between dexamethasone suppression test (DST) status and a series of multihormonal responses to apomorphine (APO), clonidine (CLO), and D-fenfluramine (FEN) tests. DST nonsuppressors did not present any difference compared with suppressors in growth hormone (GH) and cortisol stimulation by APO suggesting that a chronic elevation of cortisol did not lead to an alteration of dopaminergic activity in this population of nonpsychotic depressed inpatients. Cortisol and prolactin responses to FEN were comparable in nonsuppressors and in suppressors. In contrast, GH response to CLO was lower in DST nonsuppressors than in suppressors (p < .03), suggesting that the HPA abnormality indicated by a positive DST may be related to alpha 2-adrenoreceptor dysfunction.

Transesophageal echocardiography: an objective tool in defining maximum ventricular response to intravenous fluid therapy

Ventricular preload is an important determinant of cardiac function, which is indirectly measured in the clinical setting by the pulmonary capillary wedge pressure (PCWP). Transesophageal echocardiography (TEE) is rapidly gaining acceptance as a monitor of cardiac function. Although it provides high-resolution images of cardiac structures, clinical assessment of ventricular preload using TEE has been subjective, since quantitative measurements have been difficult to perform in a timely fashion. Automated border detection (ABD) is a new technology used in conjunction with TEE that allows quantitative real-time, two-dimensional measurement of cavity areas. To determine whether enddiastolic area (EDA) measured by ABD can be used to determine an appropriate end point for intravenous fluid administration, nine mongrel dogs were studied. Anesthetized animals were hemorrhaged to achieve a central venous pressure of 0-5 mm Hg. Each animal was then given intravenous fluid (autologous blood followed by hetastarch) until a peak in thermodilution cardiac output (CO) was achieved. Measures of PCWP, EDA, CO, and left ventricular stroke work (LVSW) were obtained after each fluid bolus. Bivariate plots displaying administered volume versus CO, LVSW, and EDA revealed parallel curves for each of these variables with peaks evident at cumulative volumes of 50-55 mL/kg. Multiple regression with mixed model analysis of covariance was performed to determine the significance of EDA in relation to changes in CO and LVSW. Analysis was likewise performed comparing the relationship between PCWP and changes in CO or LVSW. A significant relationship was demonstrated when comparing EDA to changes in CO and LVSW (P = 0.03 and P < 0.0001, respectively). Similar analysis comparing PCWP to changes in CO and LVSW failed to demonstrate a significant relationship (P = 0.54 and P = 0.36, respectively). These data suggest that changes in EDA measured using TEE with ABD are related to trends in cardiac function and can suggest an appropriate end point for intravenous fluid administration as defined by maximum CO and LVSW. PCWP did not demonstrate a significant relationship to changes in CO and LVSW.

Thiazolidinediones produce a conformational change in peroxisomal proliferator-activated receptor-gamma: binding and activation correlate with antidiabetic actions in db/db mice

The thiazolidinediones are novel insulin sensitizers that serve as orally active antidiabetic agents, in rodents, nonhuman primates, and man. We have examined the effects of 4-week oral administration of three thiazolidinediones (AD-5075, BRL 49653, and CS-045) on plasma glucose and triglyceride concentrations in obese hyperglycemic db/db mice. All three agents lower plasma glucose and triglyceride concentrations. Normal levels of glucose are achieved after treatment with AD-5075 (> 1.7 mg/kg) or BRL 49653 (> or = 30 mg/kg), whereas CS-045 (100 or 300 mg/kg) produces only modest reductions in either parameter. Although the thiazolidinediones have demonstrated insulin-sensitizing activities both in vivo and in vitro, their primary molecular target has been unclear. We have compared the in vivo antidiabetic actions described above with the in vitro activities on peroxisomal proliferator-activated receptor-gamma (PPAR gamma). Hamster PPAR gamma 1 was transiently expressed in COS-1 cells to study the binding of [3H]AD-5075. The concentrations of compounds needed to displace radiolabeled AD-5075 from PPAR gamma correlate with their in vivo potency; the Ki values for displacement by cold AD-5075, BRL 49653, and CS-045 are 22, 68, and 1600 nM, respectively. To examine activation of the receptor, it was transiently cotransfected into COS-1 cells with a reporter plasmid containing two copies of a peroxisome proliferator response element. The EC50 values for activation are 2, 6, and 140 nM for AD-5075, BRL 49653, and CS-045, respectively. We have also analyzed limited proteolytic digests of in vitro translated hamster PPAR gamma. The thiazolidinediones produce a conformational change in PPAR gamma analogous to those produced by agonists of other nuclear hormone receptors. In the presence of saturating concentrations of either AD-5075 or BRL 49653, a receptor fragment of 27 kDa is protected from proteolysis by trypsin. These data support the conclusion that the antidiabetic actions of the thiazolidinediones are directly mediated through binding to PPAR gamma and the resulting active conformation of the receptor. Therefore, binding and transactivation assays using PPAR gamma should serve to identify other novel therapeutic agents with potential antidiabetic activities.

Effect of antidepressant medication on morning and evening thyroid function tests during a major depressive episode

BACKGROUND

This study sought to determine whether changes in thyroid function that may occur during antidepressant treatment are related to a direct effect of the drug on the thyroid axis or to a change in clinical state.

METHODS

Morning and evening thyroid function was evaluated in 30 euthyroid inpatients who met DSM-IV criteria for major depressive episode, by determination of free triiodothyronine, free thyroxine, and thyrotropin levels before and after 8 AM and 11 PM protirelin challenges (200 micrograms intravenously), on the same day. Results at baseline were compared with those after 1 month of antidepressant treatment with either amitriptyline hydrochloride, fluoxetine hydrochloride, or toloxatone.

RESULTS

Clinical efficacy and effects on thyroid function did not differ across the 3 antidepressant drugs. Compared with pretreatment values, significant reductions in basal serum 8 AM free thyroxine, 11 PM free thyroxine, and 8 AM free triiodothyronine levels and increases in 11 PM maximum increment in plasma thyrotropin level and the difference between 11 PM and 8 AM maximum increment in plasma thyrotropin values were observed in responders (n = 11) but not in partial responders (n = 6) or nonresponders (n = 13). Moreover, nonresponders exhibited lower pretreatment 11 PM thyrotropin values (basal and maximal increment above basal) than responders.

CONCLUSIONS

The results suggest that (1) changes in thyroid function are related to clinical recovery rather than to a direct effect of the antidepressant drug and (2) patients with the lowest pretreatment evening thyrotropin secretion have the lowest rate of antidepressant response, and this may contribute to treatment resistance.

Down-regulation of the expression of the obese gene by an antidiabetic thiazolidinedione in Zucker diabetic fatty rats and db/db mice

Obese (ob) is a recently identified gene involved in the regulation of energy balance in the mouse. We report here that AD-5075, a potent thiazolidinedione which lowered plasma glucose and triglyceride in Zucker diabetic fatty (ZDF) rats and db/db mice, decreased the expression of the ob gene in these animal models of obesity and non-insulin-dependent diabetes mellitus. The level of adipose ob mRNA in ZDF rats was 3-fold greater than that detected in the Zucker lean littermates. Chronic treatment with AD-5075 elicited a 67 and 70% reduction of ob mRNA in ZDF and control lean rats, respectively. Furthermore, the amount of adipose ob mRNA in db/db mice was 7 times higher than that detected in lean littermates. Treatment of db/db mice with AD-5075 resulted in a 78% reduction of the level of ob mRNA with parallel changes in circulating level of the ob gene product, leptin. The reduction of the ob mRNA in the Zucker lean rats was accompanied by significantly greater food intake and weight gain. However, in ZDF rats and db/db mice, there was profound increase in body weight without hyperphagia. The results demonstrate that the expression of the ob gene is up-regulated in these two rodent models of diabetes compared to their lean counterparts and that such overexpression is attenuated by treatment with an agent that improves insulin sensitivity and glucose homeostasis in vivo.

Influence of thyroid hormones on morning and evening TSH response to TRH in major depression

The serum levels of thyroid hormones and thyrotropin (TSH) were evaluated before and after 8 PM and 11 PM thyrotropin-releasing hormone (TRH) challenges, on the same day, in 41 drug-free DSM-III-R euthyroid major depressed inpatients and 16 hospitalized controls. Depressed patients exhibited elevated circulating concentrations of thyroid hormones, which were associated with and may have contributed to the blunted TSH response to TRH. This was confirmed by: (a) higher basal levels (albeit not always statistically significant) of free triiodothyronine (FT3B) and free thyroxine (FT4B) at 8 AM and 11 PM in the depressed patient population compared with the controls; (b) lower basal levels of TSH in the depressed subjects (even though this was only statistically significant at the 11 PM sampling) compared with the controls; (c) blunted TSH response to TRH (delta TSH) in the depressed group (although this was only statistically significant at 11 PM) and blunted delta delta TSH values (differences between 11 PM-delta TSH and 8 AM-delta TSH).

Negative symptoms in schizophrenia: considerations for clinical trials. Working group on negative symptoms in schizophrenia

There is little agreement about the methodology of clinical trials of antipsychotic drugs in patients with negative symptoms. A literature review revealed wide variation in experimental design, rating scales and study duration. This reflects differing views as to the definition and response to treatment of negative symptoms. Some degree of standardization would improve comparability of studies and aid the development of new compounds. Patients included in such studies should have displayed negative symptoms for at least 6 months. Depressive symptoms, positive schizophrenic symptoms and extrapyramidal signs may all influence or be confused with negative symptoms and may respond to treatment; they should be at a low level at baseline and should be measured during the study period. Studies should last at least 8 weeks. Several scales are available for measuring negative symptoms and are reviewed; a global impression score should be used additionally.

Neuroendocrine profile of SDZ HDC-912 and OPC-4392, two new atypical antipsychotic drugs, in schizophrenic patients

The aim of this study was to evaluate the effect on the activity of the hypothalamic-pituitary dopaminergic system of two new atypical antipsychotic drugs: the ergoline derivative SDZ HDC-912, which is a dopamine (DA) D2 receptor partial agonist; and the quinolinone derivative OPC-4392, which acts as an agonist at presynaptic DA autoreceptors and as an antagonist at post-synaptic D2 receptors. The effects of both compounds were compared to the effects of the benzamide derivative amisulpride. Prolactin (PRL) and growth hormone (GH) levels before and after challenge with apomorphine (Apo), a dopaminergic agonist, were determined after at least 2 weeks washout and again after 1 month of treatment in DSM-III-R schizophrenic inpatients. SDZ HDC-912 significantly decreased Apo-induced PRL inhibition, and tended to decrease PRL secretion and Apo-induced GH stimulation. OPC-4392 induced a significant decrease in baseline PRL and in Apo-induced PRL suppression, and a non-significant decrease in Apo-induced GH stimulation. The neuroendocrine profiles of these two compounds agree with their dopaminergic properties; however, the decrease in PRL basal level differentiates the two drugs from neuroleptic agents.

Estimating infant mortality rates prospectively in Honduras

In order to determine the validity of infant mortality estimates based on retrospective reporting, the Honduran Ministry of Health carried out a follow-up survey of women interviewed in a 1987 national survey. Women were interviewed approximately 14 months after the baseline survey and were asked about the outcomes of their pregnancies and the survival status of their young children. The overall infant mortality rate calculated from the follow-up survey was lower than that obtained from the baseline survey, due to the particularly low rate among the group of women who were pregnant at the time of the baseline survey. Possible explanations for this low rate are discussed.

Management and treatment of diarrhea in Honduran children: factors associated with mothers' health care behaviors

Data from the 1984 National Maternal-Child Health and Family Planning Survey in Honduras showed that one fifth (n = 711) of the children under five had experienced diarrhea on the day of the interview or the two days preceding the interview. The health care behaviors of the mothers of these children and the factors associated with these behaviors were the focus of this study. Only 22% of the mothers consulted medical personnel concerning the diarrhea episode; 74% treated their children with some type of medication while only 17% of the children received the recommended treatment, oral rehydration therapy. Most children were treated inappropriately, often receiving a combination of antibiotics, antidiarrheals and other drugs. Bivariate and multivariate analyses showed that the variables that most consistently predicted any and all three of the behaviors were the child's age and the severity of symptoms. Mothers of children two years and older were less likely to consult or use ORT than mothers of children 6-23 months of age. Mothers whose children's diarrhea had lasted three or more days or who were vomiting were usually twice as likely to consult, give any type of treatment, or give ORT than mothers whose children had diarrhea for fewer days or who were not vomiting.