Chloral Hydrate

Precise cellular localization of the GUS stain is notoriously difficult inArabidopsis seeds. Here we report an improved protocol for the clearing of seeds after GUS staining. Incubation in ethanol-acetic acid (EtAc) and Hoyer’s medium allows reliable cellular localization of the GUS, even in seeds from late developmental stages. This method also leads to the staining of nucleoli in the endosperm and embryo, facilitating nuclear counts in endosperm development.

Increased attendance at swimming pools is correlated with higher input of organic and minerals pollutants introduced by swimmers in the swimming pool water. In most swimming pools, microbiological control is performed by disinfection with the addition of chlorine. Chlorine is now well-known to lead to the formation of many disinfection by-products (DBPs) including trihalomethanes and chloramines. The hypothesis of a link between the presence of eye and skin irritation syndromes in swimmers and contact with swimming pool water treated with chlorine was initially proposed by Mood (1953). During recent decades many epidemiological studies have described the importance of DBPs generated with natural or imported organic matter present in water. Many of these DBPs are suspected to be toxic or even carcinogenic.
Trihalomethanes and haloacetic acid families are the most studied but others DBPs, like chloral hydrate, haloacetonitriles, N-nitrosodimethylamine and the bromate ion, are emerging compounds of interest. Epidemiological data about the risk of cancer are still controversial. However, numerous publications highlight a toxic risk especially the risk of allergy and respiratory symptoms for babies and elite swimmers. The few publications dedicated to risk assessment do not suggest increased risk, other than for elite swimmers. These publications are likely to underestimate the risk associated with DBPs because of the lack of data in the literature precludes the calculation of risk associated with certain compounds or certain pathways. Thus for regulations, the need to take into account the risks associated with disinfection by-products is now important without forgetting the need of the control of microbiological hazards in swimming pools.

The purpose of this study was to determine how responses in the normal human electroretinogram (ERG) change with subject age. We studied 62 children, 10 days to 15 years old, and 30 subjects 15-37 years old, using the standard protocol established by the International Society for Clinical Electrophysiology of Vision, with Burian-Allen bipolar contact-lens electrodes. We measured rod response, maximal response, oscillatory potentials (OPs), cone response, flicker response, and b-wave amplitude/log intensity (V/log I) curve. A logistic growth curve was used to describe the developmental changes. Dark- and light-adapted ERG a- and b-wave amplitudes reached adult levels by three to five years of age. although b-wave amplitudes of scotopic rod-mediated responses were slower to reach maturity than mixed rod-cone mediated responses. In early infancy OPs were the most immature of the ERG responses, although the rate of development thereafter exceeded that of the other responses such that OP...

Rhythmic movement disorder is a parasomnia that is difficult to treat. In our study, 3 weeks of controlled sleep restriction with hypnotic administration in the first week resulted in almost complete resolution of the movements in 6 children. This therapeutic success suggests that rhythmic movement disorder results from a voluntary self-soothing behavior.

Besides trihalomethanes (THMs) and haloacetic acids (HAAs), chloral hydrate (CH) is the next most prevalent disinfection by-product (DBP) in drinking water, formed as a result of the reaction between chlorine and natural organic matter (NOM). Chloral hydrate (trichloroacetaldehyde) should be limited in drinking water because of its adverse health effect. The controversies concerning the appearance of CH in disinfected water

A double-blind study consisting of 339 randomly selected children investigated the effects of several premedicants on the preoperative and postoperative behaviour of children who underwent day-stay surgery. Patients were allocated into two groups. Group 1 consisted of 165 children aged between 6 and 47 months. Group 2 consisted of 174 children aged four years and older to a body weight of 50 kg. Each child received one premedicant. Both groups included alprazolam 0.005 mg/kg, midazolam 0.3 mg/kg and placebo. In addition Group 1 included chloral hydrate 40 mg/kg and Group 2 diazepam 0.25 mg/kg. Chloral hydrate produced superior conditions (more patients calm or asleep) at induction of anaesthesia. Postoperative behaviour and incidence of vomiting were similar for all drugs. No premedicant reduced anxiety in the older group. The time to awaken postoperatively with diazepam was longer than with placebo. Alprazolam and midazolam were unpalatable for children over four years and conferre...

To report the largest study on the safety and effectiveness of sedation in paediatric ophthalmology in a nurse-led outpatient sedation unit. Retrospective cohort study reviewing all children who underwent sedation from January 2006 to December 2010. Patients were sedated with 80 mg/kg of chloral hydrate (CH) given orally with top up dose given at half dose as required. All demographic data, sedation and procedure duration, sedation success and adverse events were recorded. Univariate and multiple regression analyses were performed to assess factors associated with success and complications. Data was collected for 1509 sedation episodes. More boys were sedated compared with girls (56.3% vs 43.7% p=0.0003) with an average age of 23.86 months and weight of 11.76 kg. A higher proportion of patients had an American Society of Anaesthesiologists status of II than I (58.5%:41.5%, p=0.0001). Successful sedation was obtained in 96.69% of children with 4.77% requiring a top up dose to achieve this. The average sedation duration was 53.4 min (SD=21.5) with an average of 1.7 procedures performed; the most common being a detailed examination (93.5%) and electroretinogram (45.1%). Adverse events included paradoxical reaction (1.33%), oxygen desaturation (0.99%) and vomiting (0.53%). There were no serious complications or hospital admission. Multiple logistic regression analysis found weight greater than 15 kg and needing a top up dose to be significant risk factors for Failure (OR=2.49 and 8.69, respectively) and Adverse events (OR=2.1 and 3.97, respectively). Sex and American Society of Anesthesiologists Physical Status score did not significantly affect outcomes. CH sedation allows detailed examination and investigations in the majority of children with few side effects. Patients over 15 kg and need for a top up dose are risk factors for failure and adverse events. This is the largest study in the current literature looking at the use of CH sedation in ophthalmology and confirms its safety and effectiveness.

Nine male and eight female healthy volunteers were exposed to 50 or 100 ppm trichloroethylene vapors for 4 h. Blood, urine, and exhaled breath samples were collected for development of a physiologically based pharmacokinetic (PBPK) model for trichloroethylene and its two major P450-mediated metabolites, trichloroacetic acid and free trichloroethanol. Blood and urine were analyzed for trichloroethylene, chloral hydrate, free trichloroethanol and trichloroethanol glucuronide, and trichloroacetic acid. Plasma was analyzed for dichloroacetic acid. Trichloroethylene was also measured in exhaled breath samples. Trichloroethylene, free trichloroethanol, and trichloroacetic acid were found in blood samples of all volunteers and only trace amounts of dichloroacetic acid (4-12 ppb) were found in plasma samples from a few volunteers. Trichloroethanol glucuronide and trichloroacetic acid were found in urine of all volunteers. No chloral hydrate was detected in the volunteers. Gender-specific PB...