Gliotoxin induces apoptosis in mouse L929 fibroblast cells

The effect of the fungal toxin gliotoxin on the adherence and viability of mouse L929 cultured cells was examined. Gliotoxin at concentrations below 2 microM had no effect on cell function. The initial effect of exposure (6 h) resulted in the loss of cell adherence, with the non-adhered cells retaining viability. However, prolonged exposure (24 h) did not significantly enhance gliotoxin's effect on cell adherence, though the majority of non-adhered cells were found to have died by apoptosis, as confirmed from (i) electron microscopic examination and (ii) agarose gel electrophoresis of isolated DNA. The addition of foetal bovine serum to the culture medium had no effect on gliotoxin's activity. Ethanol (gliotoxin's solvent) had no effect on the assayed cell functions suggesting that the observed effects are due to gliotoxin alone. These results demonstrate for the first time that gliotoxin can cause apoptosis in cells of non-haematopoietic origins.     

Noonan syndrome and its related disorders

The diagnosis of Noonan syndrome still rests on its clinical features. There are several syndromes to consider in the diagnosis of Noonan syndrome. These include cardio-facial-cutaneous syndrome, LEOPARD syndrome, neurofibromatosis-Noonan syndrome and Costello syndrome. The facial appearance and part of the clinical features of these syndromes are very similar to Noonan syndrome. Molecular research likely will elucidate whether these syndromes are variations of Noonan syndrome or etiologically different disorders.     

Obstructive sleep apnea and related disorders

OSAS, a common cause of disrupted sleep and EDS, result from repetitive closure of the upper airway during sleep. It probably represents the most severe syndrome related to obstruction of the upper airway; less severe forms include UARS, a syndrome characterized by the need for increased effort to breath but no prominent apneas or hypopneas, and primary snoring. Initial clues to the presence of OSAS and related disorders are derived from the history and include loud snoring, EDS or insomnia, and witnessed apneas. Some patients, especially women, may complain mostly of tiredness or fatigue, and children may present with behavioral abnormalities. Obesity, a large neck circumference, and a crowded oropharynx are common on physical examination. Nonobese patients, in particular, often have retrognathia, a high-arched narrow palate, macroglossia, enlarged tonsils, temporomandibular joint abnormalities, or chronic nasal obstruction. The clinical suspicion of obstructed nocturnal breathing is confirmed by overnight polysomnography, and an MSLT may be used to assess sleepiness. Esophageal manometry during polysomnography facilitates diagnosis of UARS. Treatment most commonly consists of nasal CPAP or BPAP, although problems with compliance make surgical treatment preferable in some cases. Although UPPP eliminates sleep apnea only in a minority of patients, combining UPPP with maxillofacial procedures appears to improve outcomes. Other treatments such as the use of dental appliances or medications, weight loss, and positional therapy may be useful as adjunctive therapy for moderate to severe OSAS or as primary treatments for UARS or mild OSAS.     

Causal inference and related statistical methods

Statistical approaches for evaluating causal effects and for discovering causal networks are discussed in this paper.A causal relation between two variables is different from an association or correlation between them.An association measurement between two variables and may be changed dramatically from positive to negative by omitting a third variable,which is called Yule-Simpson paradox.We shall discuss how to evaluate the causal effect of a treatment or exposure on an outcome to avoid the phenomena of Yule-Simpson paradox. Surrogates and intermediate variables are often used to reduce measurement costs or duration when measurement of endpoint variables is expensive,inconvenient,infeasible or unobservable in practice.There have been many criteria for surrogates.However,it is possible that for a surrogate satisfying these criteria,a treatment has a positive effect on the surrogate,which in turn has a positive effect on the outcome,but the treatment has a negative effect on the outcome,which is called the surrogate paradox.We shall discuss criteria for surrogates to avoid the phenomena of the surrogate paradox. Causal networks which describe the causal relationships among a large number of variables have been applied to many research fields.It is important to discover structures of causal networks from observed data.We propose a recursive approach for discovering a causal network in which a structural learning of a large network is decomposed recursively into learning of small networks.Further to discover causal relationships,we present an active learning approach in terms of external interventions on some variables.When we focus on the causes of an interest outcome, instead of discovering a whole network,we propose a local learning approach to discover these causes that affect the outcome.     

Minocycline related lupus

The determination of a factor triggering lupus-like symptoms could yield new insights into the management of rheumatic disease. We describe a case of minocycline related lupus in a young patient positive for HLA-DR2 who was prescribed minocycline 4 times for mild acne and developed rheumatic symptoms each time. We review 8 other cases.     

Vicarious trial and error and related behavior.

Empirical material relating to "vicarious trial-and-error" (VTE) is summarized and evaluated critically in terms of criteria for VTE, of antecedents to and response correlates of VTE, and of VTE and learning efficiency. It is proposed that the criterion for scoring VTE behavior should be the AB unit [S's "… looking at or facing one side or card and then turning toward and looking at (or facing) the other side or card before making a choice… "]. Doubts are raised concerning the Muenzinger and Tolman VTE and learning efficiency hypothesis and an alternative explanation is advanced, "… based on an analysis of the role of position preferences supplemented by principles of conflict… ." 63 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Piezoelectric and related properties of hydrated collagen

Two piezoelectric constants (polarization per unit stress, d=d'-id', and polarization per unit strain, e=e'-ie'), the elastic constant, and dielectric constant are determined for oriented collagen at different hydration levels at 10 Hz from -150 to 50 degrees C. With no hydration (approximately 0% H2O), d' increases slightly with higher temperatures, while e' decreases slightly. Near 11 wt% H2O, both d' and e' increase then decrease around 0 degrees C, and is probably caused by an increase of the dielectric constant and the ionic conductivity in the nonpiezoelectric phase. Hydration greater than 25 wt%, d' and e' decrease above -50 degrees C which is considered to be due to a greater ionic conductivity surrounding the piezoelectric phase.     

Cardiovascular system related peptides and hypothalamic neurons

The hypothalamus is known to be an integrative site of cardiovascular, endocrine and autonomic functions. Our previous studies, using extracellular, intracellular and/or whole cell patch-clamp recordings in rat hypothalamic slice preparations, revealed that cardiovascular related peptides such as atrial natriuretic polypeptides (ANP), B-type polypeptides (BNP), endothelin (ET), angiotensin II (AII) and interleukin-1 beta (IL-1 beta) influence the hypothalamic neurons. ANP modulated the firing rates in the supraoptic nucleus (SON). BNP inhibited the SON neurons and these effects were mediated through cGMP and cGMP-dependent protein kinase. ET also inhibited approximately 60% of SON neurons. By using slice patch-clamp techniques, AII inhibited the transient outward potassium current in the SON neurons. IL-1 beta increased the firing rate and depolarized the membrane of the most SON neurons. A new type of transmitter, nitric oxide (NO), identified as an endothelial-derived relaxing factor (EDRF), modulated the glutaminergic inputs of the SON neurons. The results suggest that cardiovascular related peptides and NO modulate the neuronal activity of neurosecretory cells in the SON.     

Nature of non-ulcer dyspepsia and related conditions

To date, the precise role of Helicobacter pylori in the pathogenesis of NUD remains uncertain. There is some evidence to suggest that the organism is implicated in specific subgroups (mostly the ulcer-like form), but it is not enough for any firm conclusions to be drawn as to the importance of the bacterium as a cause of dyspeptic symptoms or as to the efficacy of anti-infective regimens in the treatment of NUD. Large, well-designed prospective studies with a long-term follow-up are needed to establish which subgroups of dyspeptic patients may benefit most from eradication of H. pylori.     

Retention of related and unrelated sentences.

Memory for meaningful information was studied in 5 experiments investigating the effect on retention exerted by one sentence upon another when learned together as part of a set. Each experiment used 10th or 11th graders ( N = 404) from a different school. Effects were hypothesized to result from semantic linking by common concepts or by linking that reflected semantic ordering. Linking of sentences improved retention in 2 of the 1st 3 experiments; in the other, where overt answers to questions about the sentences were not required at the time of learning, retention was not enhanced. The last 2 experiments indicated that semantic ordering of sentences increased the number of sentences retained and that this effect was greater than could be accounted for by common linking concepts. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)