Diversity of Cl− Channels

Cl− channels are widely found anion pores that are regulated by a variety of signals and that play various roles. On the basis of molecular biologic findings, ligand-gated Cl− channels in synapses, cystic fibrosis transmembrane conductors (CFTRs) and ClC channel types have been established, followed by bestrophin and possibly by tweety, which encode Ca2+-activated Cl− channels. The ClC family has been shown to possess a variety of functions, including stabilization of membrane potential, excitation, cellvolume regulation, fluid transport, protein degradation in endosomal vesicles and possibly cell growth. The molecular structure of Cl− channel types varies from 1 to 12 transmembrane segments. By means of computer-based prediction, functional Cl− channels have been synthesized artificially, revealing that many possible ion pores are hidden in channel, transporter or unidentified hydrophobic membrane proteins. Thus, novel Cl−-conducting pores may be occasionally discovered, and evidence from molecular biologic studies will clarify their physiologic and pathophysiologic roles

Arztbegleiteter Patiententransport

Introduction. To relieve existing interhospital transfer systems, a novel transfer vehicle was introduced in Bavaria in 2009. Its aim was to transfer patients who need care by an emergency physician but are not considered intensive care patients. Method. Logistic data (time, duration, location, distance, hospital units) and relevant medical data (urgency, medication, ventilation, special monitoring) were documented. Simultaneously the transport volume of the existing systems were evaluated after the introduction of the novel vehicle. Results. A total of 1762 transfers were documented (on average 1.6/day): 84% took place weekdays and 85% during daytime. Intensive care procedures like invasive hemodynamic monitoring, ventilation, and continuous medication were performed in 51% of patients. In 20 %, discontinuous medication was needed. In 16%, an indication for monitoring by a physician existed. Due to an overall increasing transfer volume no relevant relief was seen for the existing systems. Discussion. There seems to be a need for physician-staffed interhospital transfers especially weekdays during the daytime. In half of the transfers, intensive care-related procedures were performed. Only one third of the patients fulfilled the criteria defined at introduction of the novel vehicle. Therefore a revision of the system seems necessary

Extrakorporale CO2-Elimination als Alternative zur Tracheotomie bei Weaningversagen

We report a patient with chest trauma who was admitted to the ICU after surgery. As he fulfilled protocol-based criteria, he was extubated 7 days after admission. However, despite intermittent non-invasive ventilation, the patient had to be re-intubated on day 10 owing to progressive hypercapnia. We decided to support the patient with a mid-flow veno-venous extracorporeal carbon dioxide removal (ECCO(2)aEuroR) system instead of a tracheotomy. Sufficient CO2 removal was established with a blood flow of 1.5 l/min and the patient was successfully extubated within a few hours. After 5 days of ECCO(2)aEuroR the patient could be weaned and transferred to a general ward in a stable condition

Diversity of the basic defect of homozygous CFTR mutation genotypes in humans

BACKGROUND: Knowledge of how CFTR mutations other than F508del translate into the basic defect in cystic fibrosis (CF) is scarce due to the low incidence of homozygous index cases. METHODS: 17 individuals who are homozygous for deletions, missense, stop or splice site mutations in the CFTR gene were investigated for clinical symptoms of CF and assessed in CFTR function by sweat test, nasal potential difference and intestinal current measurement. RESULTS: CFTR activity in sweat gland, upper airways and distal intestine was normal for homozygous carriers of G314E or L997F and in the range of F508del homozygotes for homozygous carriers of E92K, W1098L, R553X, R1162X, CFTRdele2(ins186) or CFTRdele2,3(21 kb). Homozygotes for M1101K, 1898+3 A-G or 3849+10 kb C-T were not consistent CF or non-CF in the three bioassays. 14 individuals exhibited some chloride conductance in the airways and/or in the intestine which was identified by the differential response to cAMP and DIDS as being caused by CFTR or at least two other chloride conductances. DISCUSSION: CFTR mutations may lead to unusual electrophysiological or clinical manifestations. In vivo and ex vivo functional assessment of CFTR function and in-depth clinical examination of the index cases are indicated to classify yet uncharacterised CFTR mutations as either disease-causing lesions, risk factors, modifiers or neutral variants