Neural mechanisms of context-dependent processing of CO2 avoidance behavior in fruit flies.

The fruit fly, Drosophila melanogaster, innately avoids even low levels of CO2. CO2 is part of the so-called Drosophila stress odor produced by stressed flies, but also a byproduct of fermenting fruit, a main food source, making the strong avoidance behavior somewhat surprising. Therefore, we addressed whether feeding states might influence the fly's behavior and processing of CO2. In a recent report, we showed that this innate behavior is differentially processed and modified according to the feeding state of the fly. Interestingly, we found that hungry flies require the function of the mushroom body, a higher brain center required for olfactory learning and memory, but thought to be dispensable for innate olfactory behaviors. In addition, we anatomically and functionally characterized a novel bilateral projection neuron connecting the CO2 sensory input to the mushroom body. This neuron was essential for processing of CO2 in the starved fly but not in the fed fly. In this Extra View article, we provide evidence for the potential involvement of the neuromodulator dopamine in state-dependent CO2 avoidance behavior. Taken together, our work demonstrates that CO2 avoidance behavior is mediated by alternative neural pathways in a context-dependent manner. Furthermore, it shows that the mushroom body is not only involved in processing of learned olfactory behavior, as previously suggested, but also in context-dependent innate olfaction.

[Variety of symptoms after drug use of gamma-hydroxybutyric acid (GHB)]. / Symptomvielfalt nach Konsum der Droge Gamma-Hydroxybuttersäure (GHB).

Gamma-hydroxybutyric acid (GHB, "liquid ecstasy") and its legal prodrugs gamma-butyrolactone and 1,4-butanediol are gaining importance as recreational drugs in Germany. Because of the wide availability of GHB and its prodrugs physicians are increasingly being confronted with cases of intoxication. The effect of GHB intoxication is comparable with those of alcohol and/or benzodiazepines. Likewise, symptoms of withdrawal may occur. In this review, we summarise current data regarding the history, pharmacodynamics and pharmacokinetics of the drug as well as the relevant symptoms of intoxication or withdrawal as they pertain to neurology and psychiatry.

General non-specific morbidity is reduced after vaccination within the third month of life--the Greifswald study.

OBJECTIVES: The incidence of many serious infectious diseases fundamentally decline as a success of consequent vaccination regimens. However, it is a matter of discussion if vaccination might cause unspecific negative side effects on the immune system. To answer this, we performed a clinical study on children with the question as to whether there is an enhanced frequency of infection diseases after vaccination or not. METHODS: The study population (n=496) was randomized to a group of vaccinated children (first vaccination on the 60th day of life, n=201) and a group of unvaccinated children (first vaccination on the 90th day of life, n=295). Frequencies of unspecific, morbidity-related signs were recorded by the mothers with a diary card. These data were taken for further statistical analysis to determine if the factor "vaccination" does have a significant effect on the variable "morbidity". RESULTS: Various infectious disease-associated symptoms (vomiting, coughing, signs of rhinitis, restlessness, rash and pain) were significantly less often seen in vaccinated than in non-vaccinated children. CONCLUSIONS: Our study revealed that children who received vaccination against diphtheria, pertussis, tetanus, HiB and poliomyelitis simultaneously within the third month of life do not exhibit enhanced frequencies of infectious disease-associated symptoms. In contrary, the frequencies of infection-associated symptoms were found to be significantly reduced. This might be caused by a vaccination-associated unspecific enhancement of immunological activity (e.g. mediated by interleukin 2) or by other presently still unknown factors.

[Hepatitis B screening in pregnant patients and their children. A Greifswald perinatology-pediatric study. II. Pediatric findings]. / Hepatitis B-Screening bei Schwangeren und ihren Kindern. Eine Greifswalder perinatologisch-pädiatrische Studie. II. Kindliche Befunde.

Hepatitis B virus carriers were identified by a systematic screening of women during the last trimester of pregnancy. With 0.5% the HBV carrier incidence was found to be constant over years. 25 children of HBsAg positive women were followed after 2-4 years in order to define the risk of vertical transmission. One infant died due to the sequelae of a congenital malformation. In 12 of the remaining infants HBV markers were found after different intervals, in 10 of them also clinical and paraclinical symptoms of HBV infection could be diagnosed. The results are discussed in relation to the maternal serologic status and with regard to different preventive measures. Summarizing our results the following recommendations can be given: A mass screening for HBV during pregnancy is the only safe method of diagnosing HBsAg positive carriers. All newborns of HBsAg positive pregnants should be vaccinated immediately after birth, both actively and passively.