Test-retest reliability of the P50 mid-latency auditory evoked response.

Attenuation in mid-latency auditory evoked responses (MLAERs) can be used to study sensory gating. If paired-click stimuli (S1 and S2) are used, lower amplitude in response to S2 vs. S1 (attenuation) is considered evidence for intact sensory gating. However, the need for reliable measurements of MLAER amplitude and attenuation is a recognized problem. Ten normal volunteers were studied six times each. An S1 amplitude test-retest reliability coefficient (r) of 0.585 was obtained when means of two recordings were used vs. reliability coefficients as high as 0.809 for means of six recordings. Averaging a higher number of runs (120 vs. 60) resulted in a reliability coefficient of 0.677/recording. Similar values were obtained for S1 and S2 latencies. Reliability coefficients for S2 attenuation (S2/S1) were not nearly as high (a value of 0.138 when means of all six recordings were used). The S1 amplitude as measured in this study (with 120 averages) appears to be a reliable psychophysiologic measurement, but the S2/S1 attenuation measure is more variable, perhaps reflecting a greater sensitivity of the S2/S1 to uncontrolled variables in this study. Further research to identify such variables is necessary.     

Plasma HIV-1 RNA decline within the first two weeks of treatment is comparable for nevirapine, efavirenz, or both drugs combined and is not predictive of long-term virologic efficacy: A 2NN substudy

BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.     

Electromyographic and affective responses of episodic tension-type headache patients and headache-free controls during stressful task performance

Thirty-four subjects meeting diagnostic criteria for episodic tension-type headache and 42 who rarely experienced headaches participated in two laboratory sessions in which cephalic electromyographic (EMG) activity, electrodermal activity, heart rate, and finger temperature were recorded. Subjects performed relaxation, choice reaction time, psychomotor tracking, voluntary muscle contraction, and cold pressor tasks. Headache subjects showed significantly greater EMG activity than controls during baseline and stressful task performance. During relaxation, both groups reduced EMG activity from baseline levels, and there was no significant difference in EMG level between the groups during relaxation. Headache subjects reported higher levels of subjective anxiety, depression, anger, and stress than controls. Headache subjects also reported higher levels of pain than controls, and headache subjects reported greater pain during stressful task performance relative to baseline and recovery periods.This research was supported by NIH Grant R01-NS-25114.     

Acute airway obstruction following placement of a subclavian Hickman catheter

The purpose of this case report is to describe the events, intervention, and aetiology which led to acute airway obstruction in an adult patient after the placement of a Hickman catheter. Airway obstruction secondary to superior vena cava obstruction occurred after placement of a subclavian vein Hickman catheter. This was felt to occur, in part, to a narrowed superior vena cava as evident by subclavian venography. It resulted in emergency oral tracheal intubation to relieve airway obstruction. Shortly after removal of the Hickman catheter, the signs of superior vena cava obstruction syndrome resolved and the patient was extubated without incidence. It is concluded that, although rare, the serious complication of acute airway obstruction can occur after placement of a Hickman catheter.     

Altered NMDA glutamate receptor antagonist response in recovering ethanol-dependent patients.

Ethanol is an antagonist of the N-methyl-D-aspartate (NMDA) glutamate receptor. Ethanol dependence upregulates NMDA receptors and contributes to crosstolerance with selective NMDA receptor antagonists in animals. This study evaluated whether recovering ethanol-dependent patients show evidence of a reduced level of response to the effects of the NMDA receptor antagonist, ketamine. In this double-blind study, 34 recently detoxified alcohol-dependent patients and 26 healthy comparison subjects completed 3 test days involving a 40-min infusion of saline, ketamine 0.1 mg/kg, or ketamine 0.5 mg/kg in a randomized order. Recovering ethanol-dependent patients showed reduced perceptual alterations, dysphoric mood, and impairments in executive cognitive functions during ketamine infusion relative to the healthy comparison group. No attenuation of ketamine-induced amnestic effects, euphoria, or activation was observed. The alterations in NMDA receptor function observed in recovering ethanol-dependent patients may have important implications for ethanol tolerance, ethanol dependence, and the treatment of alcoholism.     

Audit of a children's epilepsy clinic

A newly established tertiary epilepsy clinic at Guy's Hospital, London was evaluated using a structured questionnaire. Fifty parents of children with epilepsy completed this questionnaire, with some contribution from the children. While a high degree of satisfaction was obtained by the parents and where appropriate the children, specific questions about additional resources implied a large number of unmet needs. This raises methodological issues about the value of open-ended questions in audit questionnaires. In addition, concerns were expressed about many areas, some of which had direct medical implications that were not always raised with the doctors. It is concluded that the service has benefited from both clinical and neuropsychological support. The audit has prompted a number of improvements, including establishing a discussion group for adolescents.     

Factors Affecting Utilization of Family Planning Services in a Post-Conflict Setting,South Sudan: A Qualitative Study

This study aims to explore and examine the conjectures surrounding the utilization of family planning services among currently married couples of childbearing age in Renk County.This study has adopted a qualitative method to collect data on factors affecting the utilization of family planning services through focus group discussions and in-depth interviews, in rural and urban areas of Renk County. It targeted married women, men as well as unmarried men and women. The researchers conducted nine focus group discussions and nine interviews at both Jelhak (rural setting) and Renk (urban setting). The results suggested that the people of Renk County prefer to have large families and therefore choose not to use family planning methods. The data collected was analyzed by means of thematic analysis. This included the construction of a thematic framework, coding, editing and categorization of available data as well as the creation of sub-themes.The result also suggested that perception is a main factor that affects utilization of family planning services with a majority of the people in Renk and Jelhak preferring to have many children in order to increase the family size for some reasons. These are linked to religion, social stigma and taboo that are attached to childless people or users of family planning methods for birth control purposes.The responses revealed some variation in perception between rural (Jelhak) and urban (Renk) areas. Respondents from Renk area reported that some people use family planning services for economic reasons that involve alleviation of financial difficulties and provision of better education when the family size is small. On the other hand, rural people from Jelhak perceive family planning to be socially un-acceptable. Furthermore, men and women of Jelhak reported that after each birth of a child, married couples avoid sexual relationship for a period of two years as means of family planning. Women of both Urban and Rural settings reported intentions to use conventional methods of family planning without the knowledge of their spouses.     

Phenotypical heterogeneity in RAG-deficient patients from a highly consanguineous population

Mutations affecting recombination activation genes RAG1 and RAG2 are associated with variable phenotypes, depending on the residual recombinase activity. The aim of this study is to describe a variety of clinical phenotypes in RAG-deficient patients from the highly consanguineous Egyptian population. Thirty-one patients with RAG mutations (from 28 families) were included from 2013 to 2017. On the basis of clinical, immunological and genetic data, patients were subdivided into three groups; classical T^–B^– severe combined immunodeficiency (SCID), Omenn syndrome (OS) and atypical SCID. Nineteen patients presented with typical T^–B^–SCID; among these, five patients carried a homozygous RAG2 mutation G35V and five others carried two homozygous RAG2 mutations (T215I and R229Q) that were detected together. Four novel mutations were reported in the T^–B^–SCID group; three in RAG1 (A565P, N591Pfs*14 and K621E) and one in RAG2 (F29S). Seven patients presented with OS and a novel RAG2 mutation (C419W) was documented in one patient. The atypical SCID group comprised five patients. Two had normal B cell counts; one had a previously undescribed RAG2 mutation (V327D). The other three patients presented with autoimmune cytopaenias and features of combined immunodeficiency and were diagnosed at a relatively late age and with a substantial diagnostic delay; one patient had a novel RAG1 mutation (C335R). PID disorders are frequent among Egyptian children because of the high consanguinity. RAG mutations stand behind several variable phenotypes, including classical SCID, OS, atypical SCID with autoimmunity and T^–B⁺ CID.     

Adolescent Intermittent Ethanol Exposure Is Associated with Increased Risky Choice and Decreased Dopaminergic and Cholinergic Neuron Markers in Adult Rats

Background:

Binge drinking is prevalent during adolescence and may have effects on the adult brain and behavior. The present study investigated whether adolescent intermittent ethanol exposure alters adult risky choice and prefrontal dopaminergic and forebrain cholinergic neuronal marker levels in male Wistar rats.

Methods:

Adolescent (postnatal day 28–53) rats were administered 5g/kg of 25% (vol/vol) ethanol 3 times/d in a 2-days–on/2-days–off exposure pattern. In adulthood, risky choice was assessed in the probability discounting task with descending and ascending series of large reward probabilities and after acute ethanol challenge. Immunohistochemical analyses assessed tyrosine hydroxylase, a marker of dopamine and norepinephrine in the prelimbic and infralimbic cortices, and choline acetyltransferase, a marker of cholinergic neurons, in the basal forebrain.

Results:

All of the rats preferred the large reward when it was delivered with high probability. When the large reward became unlikely, control rats preferred the smaller, safe reward, whereas adolescent intermittent ethanol-exposed rats continued to prefer the risky alternative. Acute ethanol had no effect on risky choice in either group of rats. Tyrosine hydroxylase (prelimbic cortex only) and choline acetyltransferase immunoreactivity levels were decreased in adolescent intermittent ethanol-exposed rats compared with controls. Risky choice was negatively correlated with choline acetyltransferase, implicating decreased forebrain cholinergic activity in risky choice.

Conclusions:

The decreases in tyrosine hydroxylase and choline acetyltransferase immunoreactivity suggest that adolescent intermittent ethanol exposure has enduring neural effects that may lead to altered adult behaviors, such as increased risky decision making. In humans, increased risky decision making could lead to maladaptive, potentially harmful consequences.