Status cataplecticus induced by abrupt withdrawal of clomipramine

Introduction: Cataplexy is one of the main narcoleptic symptoms and is characterized by sudden loss of muscle tone triggered by emotional stimuli while consciousness is mantained. Clomipramine is an effective treatment of cataplexy. Cataplexy that occurs repeatedly for hours or days is referred to as status cataplecticus.Patients: We report three adults with narcolepsy in whom cataplexy was chronically and effectively treated with clomipramine (75-150 mg/day). For diverse reasons, these three patients had an abrupt withdrawal of clomipramine, and after 2-9 days patients showed an invalidant status cataplecticus characterized by a marked increase of the frequency, duration and severity of their cataplectic attacks that were now elicited by mild emotional stimuli. After introduction of anticataplectic agents (clomipramine in two patients and fluoxetine in one patient), status cataplecticus was resolved in less than a week.Conclusion: In patients with narcolepsy, abrupt withdrawal of chronic treatment with clomipramine may be associated with status cataplecticus. This condition may be resolved with the reintroduction of anticataplectic agents.     

Implicit and explicit alcohol-related cognitions

This article presents the proceedings of a symposium at the 2001 RSA Meeting in Montreal, Canada organized by Reinout W. Wiers and Alan W. Stacy. The purpose of the symposium was to present recent applications of implicit cognitive processing theory to alcohol research. Basic cognitive research has demonstrated that implicit cognition influences memory and behavior without explicit recall or introspection. The presentations from this symposium show that implicit cognition approaches yield new insights into understanding drinking motivation. The presentations were: (1) An introduction by Alan W. Stacy; (2) Implicit cognition and alcohol use. Involvement of other variables? (Susan L. Ames); (3) Alcohol expectancies and the art of implicit priming (Jane A. Noll); (4) Parental alcoholism and the effects of alcohol on semantic priming (Michael A. Sayette); (5) Implicit arousal and explicit liking of alcohol in heavy drinkers (Reinout W. Wiers); and (6) Negative affective cues and associative cognition in problem drinkers (Martin Zack). Comments were provided by the discussant Marvin Krank. The presented studies demonstrated that: (1) implicit memories of alcohol associations are powerful predictors and cross‐sectional correlates of alcohol use; (2) implicit retrieval processes influence alcohol outcome expectancies and alcohol consumption; (3) alcohol consumption influences implicit memory processing; (4) heavy drinkers reveal different affective responses in implicit and explicit tasks; and (5) negative affect exerts an implicit priming effect for alcohol associations in problem drinkers. These findings illustrate the importance of implicit cognition in understanding alcohol abuse and demonstrate the potential of the theoretical framework for more widespread application across a variety of areas of alcohol research, including diagnostics for the risk of alcohol abuse, treatment, and prevention.     

A biomechanical study of two postoperative prostheses for transtibial amputees: a custom-molded and a prefabricated adjustable pneumatic prosthesis

We evaluated an adjustable pneumatic prefabricated prosthesis and a rigid custom-molded prosthesis for immediate postoperative use. Twelve transtibial amputations were performed on cadaver limbs. Differential variable reluctance transducers were placed subcutaneously across the wound edge medially and laterally. The limbs were then placed in either the pneumatic prosthesis (five limbs) or the rigid prosthesis (seven limbs). The specimens underwent static and cyclic loading to simulate weight bearing. The strain readings for static and cyclic loading were greater in the rigid prosthetic group. Only the mean medial strain measurement after cyclic loading was statistically significant. The results demonstrate that the pneumatic prosthesis places less strain across the wound than a rigid prosthesis.     

阿德福韦双酯治疗拉米夫定耐药的慢性乙肝患者时出现的耐药问题

背景:阿德福韦双酯(ADV) 是一种有效治疗野生型和耐拉米夫定乙肝病毒(HBV)的核苷酸类药物。在使用核苷酸类药物治疗慢性乙肝时,当治疗时间为 48、96、144周时,耐ADV变异体出现的累积发生率分别为0、 0．8-3％和0-5．9％。目的:研究67例对拉米夫定耐药且接受ADV治疗的慢性乙肝患者耐ADV病毒变异体的表型和基因型特点。方法:HBV DNA含量采用实时定量PCR技术。ADV变异体检测采用基质辅助激光解吸电离／飞行时间质谱为基础的基因分型     

Anterior cingulate and the monitoriing of response conflict: evidence from an fMRI study of overt verb generation

Studies of a range of higher cognitive functions consistently activate a region of anterior cingulate cortex (ACC), typically posterior to the genu and superior to the corpus collosum. In particular, this ACC region appears to be active in task situations where there is a need to override a prepotent response tendency, when responding is underdetermined, and when errors are made. We have hypothesized that the function of this ACC region is to monitor for the presence of "crosstalk" or competition between incompatible responses. In prior work, we provided initial support for this hypothesis, demonstrating ACC activity in the same region both during error trials and during correct trials in task conditions designed to elicit greater response competition. In the present study, we extend our testing of this hypothesis to task situations involving underdetermined responding. Specifically, 14 healthy control subjects performed a verb-generation task during event-related functional magnetic resonance imaging (fMRI), with the on-line acquisition of overt verbal responses. The results demonstrated that the ACC, and only the ACC, was more active in a series of task conditions that elicited competition among alternative responses. These conditions included a greater ACC response to: (1) Nouns categorized as low vs. high constraint (i.e., during a norming study, multiple verbs were produced with equal frequency vs. a single verb that produced much more frequently than any other); (2) the production of verbs that were weak associates, rather than, strong associates of particular nouns; and (3) the production of verbs that were weak associates for nouns categorized as high constraint. We discuss the implication of these results for understanding the role that the ACC plays in human cognition.     

Resistance of Copenhagen rats to chemical induction of glutathione S- transferase 7-7-positive liver foci

Copenhagen (Cop) rats are completely resistant to the chemical induction of mammary adenocarcinomas, but their susceptibility to hepatocarcinogenesis is virtually unknown. Rat liver is a well- characterized and easily manipulated tissue in which to study carcinogenesis. Therefore, if Cop rats are resistant to hepatocarcinogenesis, studies into resistance mechanisms may be feasible. Male Cop and F344 rats, 7-8 weeks old, were initiated using either N-nitrosodiethylamine (DEN) (200 mg/kg, i.p.) or a two-thirds partial hepatectomy (PH) followed by N-methyl-N-nitrosourea (MNU) (60 mg/kg, i.p.). The rats were then promoted using a modified resistant hepatocyte (RH) protocol (a combination of four doses of 2- acetylaminofluorene (2-AAF) and a single dose of CCl4 that provides a selective mitotic stimulus for initiated cells). Six weeks after initiation the rats were killed and liver sections were stained for glutathione S-transferase 7-7 (GST 7-7), a marker for putative preneoplastic hepatocytes. Cop rats were found to be highly resistant, having a approximately 9- and approximately 27-fold smaller percentage of liver area occupied by GST 7-7-positive foci than susceptible F344 rats following initiation by DEN and MNU respectively. Furthermore, gross liver nodules did not form in any of the Cop rats, whereas all F344 rat livers contained nodules. Hepatic necrosis caused by DEN during initiation, and CCl4 during promotion is necessary to stimulate compensatory hepatocyte division. We demonstrated that these agents do indeed increase serum transaminase levels and produce histologic evidence of necrosis in Cop rats. In order for liver foci to grow rapidly in the RH protocol, the surrounding normal hepatocytes must be mito-inhibited by 2-AAF. We found that the degree of mito-inhibition of normal hepatocytes by 2-AAF is the same in Cop and F344 rats. These results show that the Cop rat is highly resistant to the chemical induction of putative preneoplastic liver foci and nodules.      

Nasal inflammation and chronic ear disease in Australian Aboriginal children

Objective : Chronic middle ear disease is common in Aboriginal children, and may be linked to nasal inflammation and Eustachian tube dysfunction. The pattern of nasal inflammation is unknown. The study reported here was performed to define the role of allergy and infection in causing nasal inflammation in Aboriginal children with chronic middle ear disease.
Methodology : Thirty-one Aboriginal children aged between 3 and 7 years underwent clinical assessment, audiometry and allergy skin tests. Nasal swabs for bacterial culture and cytology were performed during the winter and again in spring to identify any seasonal variation. A randomized trial of nasal beclomethasone for 8 weeks was conducted in children with abnormal tympanometry to identify the effect of therapy upon nasal cytology.
Results : Twenty-six of the 31 children had abnormal tympanograms. Average hearing levels were reduced in nine children. Pathogenic organisms were isolated from most children: Streptococcus pneumoniae (82%), Haemophilus influenzae (79%), Moraxella catarrhalis (39%) and Staphylococcus aureus (29%). Eight of the 31 children (26%) were atopic. Nasal cytology disclosed a marked neutrophil infiltrate (80% of cells) during the winter, which fell significantly in spring to 52% of cells. Only two subjects had nasal eosinophilia of >10%. There was no effect of beclomethasone on nasal cytology.
Conclusions : Chronic ear disease in Aboriginal children is associated with nasal inflammation, neutrophil infiltration and the presence of bacteria. These features suggest respiratory infection as the main cause of chronic nasal inflammation in Aboriginal children with middle ear disease. There is a seasonal variation in the severity of the nasal infiltrate, consistent with increased infections during winter. Despite a high prevalence of atopy, allergic nasal disease was uncommon.     

Histidinaemia: a benign metabolic disorder

Histidinaemia is a relatively common inherited metabolic disorder with an incidence similar to phenylketonuria. This paper reports the long term outcome of patients diagnosed by newborn screening in the north west of England. Between 1966 and 1990, 108 infants were diagnosed as having histidinaemia by a regional neonatal screening programme (incidence 1:11,083). A further five children were detected following diagnosis in a sibling. Of the 113, nine were lost to follow up. Infants diagnosed before 1981 (n = 47) were placed on a low histidine diet (225 mg/kg/d) for an average period of 21 months (SD 4.5). All patients were reviewed regularly, Griffiths developmental quotients (DQ) were assessed at 2 and 4 years, and WISC-R intelligence quotients (IQ) at 8, 12, and 18 years. IQ data were converted to standard deviation scores (IQ SDS) to account for increasing IQ norms with time. Neither DQ nor IQ correlated with plasma histidine at diagnosis or with the mean plasma histidine throughout life. Growth was normal in all patients. There was no apparent benefit from a low histidine diet in early childhood. In contrast to other studies, there was no excess of clinical symptoms. On the basis of these findings, histidinaemia is a benign metabolic disorder that does not require treatment.     

Pericardial effusion complicating a percutaneous central venous line in a neonate

A premature infant developed pericardial effusion four days after the insertion of a 25-gauge silastic percutaneous central venous catheter. The effusion contained parenteral nutrition fluid and resolved rapidly after withdrawal of the catheter. Pericardial effusion is a potential complication of percutaneous, as well as surgically placed, central venous catheters.