Molecular phylogeny and forms of photosynthesis in tribe Salsoleae (Chenopodiaceae)

While many C4 lineages have Kranz anatomy around individual veins, Salsoleae have evolved the Salsoloid Kranz anatomy where a continuous dual layer of chlorenchyma cells encloses the vascular and water-storage tissue. With the aim of elucidating the evolution of C4 photosynthesis in Salsoleae, a broadly sampled molecular phylogeny and anatomical survey was conducted, together with biochemical, microscopic, and physiological analyses of selected photosynthetic types. From analyses of photosynthetic phenotypes, a model for evolution of this form of C4 was compared with models for evolution of Kranz anatomy around individual veins. A functionally C3 proto-Kranz phenotype (Proto-Kranz Sympegmoid) and intermediates with a photorespiratory pump (Kranz-like Sympegmoid and Kranz-like Salsoloid types) are considered crucial transitional steps towards C4 development. The molecular phylogeny provides evidence for C3 being the ancestral photosynthetic pathway but there is no phylogenetic evidence for the ancestry of C3-C4 intermediacy with respect to C4 in Salsoleae. Traits considered advantageous in arid conditions, such as annual life form, central sclerenchyma in leaves, and reduction of surface area, evolved repeatedly in Salsoleae. The recurrent evolution of a green stem cortex taking over photosynthesis in C4 clades of Salsoleae concurrent with leaf reduction was probably favoured by the higher productivity of the C4 cycle.

When do different C4 leaf anatomies indicate independent C4 origins? Parallel evolution of C4 leaf types in Camphorosmeae (Chenopodiaceae)

Broad-scale phylogenetic studies give first insights in numbers, relationships, and ages of C4 lineages. They are, however, generally limited to a model that treats the evolution of the complex C4 syndrome in different lineages as a directly comparable process. Here, we use a resolved and well-sampled phylogenetic tree of Camphorosmeae, based on three chloroplast and one nuclear marker and on leaf anatomical traits to infer a more detailed picture of C4 leaf-type evolution in this lineage. Our ancestral character state reconstructions allowed two scenarios: (i) Sedobassia is a derived C3/C4 intermediate, implying two independent gains of C4 in Bassia and Camphorosma; or (ii) Sedobassia is a plesiomorphic C3/C4 intermediate, representing a syndrome ancestral to the Bassia/Camphorosma/Sedobassia lineage. In Bassia, a kochioid leaf type (Bassia muricata and/or Bassia prostrata type) is ancestral. At least three independent losses of water-storage tissue occurred, resulting in parallel shifts towards an atriplicoid leaf type. These changes in leaf anatomy are adaptations to different survival strategies in steppic or semi-desert habitats with seasonal rainfall. In contrast, Camphorosma shows a fixed C4 anatomy differing from Bassia types in its continuous Kranz layer, which indeed points to an independent origin of the full C4 syndrome in Camphorosma, either from an independent C3 or from a common C3/C4 intermediate ancestor, perhaps similar to its C3/C4 intermediate sister genus Sedobassia. The enlarged bundle sheath cells of Sedobassia might represent an important early step in C4 evolution in Camphorosmeae.

Structural and orientation effects on electronic energy transfer between silicon quantum dots with dopants and with silver adsorbates

Starting from the atomic structure of silicon quantum dots (QDs), and utilizing ab initio electronic structure calculations within the Förster resonance energy transfer (FRET) treatment, a model has been developed to characterize electronic excitation energy transfer between QDs. Electronic energy transfer rates, KEET, between selected identical pairs of crystalline silicon quantum dots systems, either bare, doped with Al or P, or adsorbed with Ag and Ag3, have been calculated and analyzed to extend previous work on light absorption by QDs. The effects of their size and relative orientation on energy transfer rates for each system have also been considered. Using time-dependent density functional theory and the hybrid functional HSE06, the FRET treatment was employed to model electronic energy transfer rates within the dipole-dipole interaction approximation. Calculations with adsorbed Ag show that: (a) addition of Ag increases rates up to 100 times, (b) addition of Ag3 increases rates up to 1000 times, (c) collinear alignment of permanent dipoles increases transfer rates by an order of magnitude compared to parallel orientation, and (d) smaller QD-size increases transfer due to greater electronic orbitals overlap. Calculations with dopants show that: (a) p-type and n-type dopants enhance energy transfer up to two orders of magnitude, (b) surface-doping with P and center-doping with Al show the greatest rates, and (c) KEET is largest for collinear permanent dipoles when the dopant is on the outer surface and for parallel permanent dipoles when the dopant is inside the QD.

The Wada test in Austrian, Dutch, German, and Swiss epilepsy centers from 2000 to 2005: a review of 1421 procedures

Twenty-six Austrian, Dutch, German, and Swiss epilepsy centers were asked to report on use of the Wada test (intracarotid amobarbital procedure, IAP) from 2000 to 2005 and to give their opinion regarding its role in the presurgical diagnosis of epilepsy. Sixteen of the 23 centers providing information had performed 1421 Wada tests, predominantly the classic bilateral procedure (73%). A slight nonsignificant decrease over time in Wada test frequency, despite slightly increasing numbers of resective procedures, could be observed. Complication rates were relatively low (1.09%; 0.36% with permanent deficit). Test protocols were similar even though no universal standard protocol exists. Clinicians rated the Wada test as having good reliability and validity for language determination, whereas they questioned its reliability and validity for memory lateralization. Several noninvasive functional imaging techniques are already in use. However, clinicians currently do not want to rely solely on noninvasive functional imaging in all patients.

Structural, biochemical, and physiological characterization of C4 photosynthesis in species having two vastly different types of kranz anatomy in genus Suaeda (Chenopodiaceae)

C (4) species of family Chenopodiaceae, subfamily Suaedoideae have two types of Kranz anatomy in genus Suaeda, sections Salsina and Schoberia, both of which have an outer (palisade mesophyll) and an inner (Kranz) layer of chlorenchyma cells in usually semi-terete leaves. Features of Salsina (S. AEGYPTIACA, S. arcuata, S. taxifolia) and Schoberia type (S. acuminata, S. Eltonica, S. cochlearifoliA) were compared to C (3) type S. Heterophylla. In Salsina type, two layers of chlorenchyma at the leaf periphery surround water-storage tissue in which the vascular bundles are embedded. In leaves of the Schoberia type, enlarged water-storage hypodermal cells surround two layers of chlorenchyma tissue, with the latter surrounding the vascular bundles. The chloroplasts in Kranz cells are located in the centripetal position in Salsina type and in the centrifugal position in the Schoberia type. Western blots on C (4) acid decarboxylases show that both Kranz forms are NAD-malic enzyme (NAD-ME) type C (4) species. Transmission electron microscopy shows that mesophyll cells have chloroplasts with reduced grana, while Kranz cells have chloroplasts with well-developed grana and large, specialized mitochondria, characteristic of NAD-ME type C (4) chenopods. In both C (4) types, phosphoenolpyruvate carboxylase is localized in the palisade mesophyll, and Rubisco and mitochondrial NAD-ME are localized in Kranz cells, where starch is mainly stored. The C (3) species S. heterophylla has Brezia type isolateral leaf structure, with several layers of Rubisco-containing chlorenchyma. Photosynthetic response curves to varying CO (2) and light in the Schoberia Type and Salsina type species were similar, and typical of C (4) plants. The results indicate that two structural forms of Kranz anatomy evolved in parallel in species of subfamily Suaedoideae having NAD-ME type C (4) photosynthesis.

Language lateralization by Wada test and fMRI in 100 patients with epilepsy

Comparing the determination of language dominance using fMRI with results of the Wada test in 100 patients with different localization-related epilepsies, the authors found 91% concordance between both tests. The overall rate of false categorization by fMRI was 9%, ranging from 3% in left-sided temporal lobe epilepsy (TLE) to 25% in left-sided extratemporal epilepsy. Language fMRI might reduce the necessity of the Wada test for language lateralization, especially in TLE.

Auswahl einer HAWIK-III-Kurzform für Kinder und Jugendliche mit Epilepsie

Zusammenfassung: Die Studie untersuchte anhand von theoretischen, statistischen und empirischen Kriterien die Eignung verschiedener bisheriger Kurzformen für den HAWIK-III bei pädiatrischen Patienten mit Epilepsie. Es wurde geprüft, welche Untertests in dieser Klientel den Gesamtwert am besten vorhersagen und welche Untertests bei fokalen Epilepsien das Leistungsprofil am besten kennzeichnen. Ausgewählt wurde schließlich eine Kurzform mit den Untertests “Wortschatz”, “Mosaiktest”, “Bilderordnen”, “Zahlen-Symbol-Test” und “Allgemeines Wissen”, wie sie von Basler 1974 für den HAWIK-R vorgeschlagen wurde. Für diese Kurzform wird über multiple Regression eine Schätzformel aufgestellt und an einer zweiten Stichprobe kreuzvalidiert. Die Ergebnisse zeigen, dass in den meisten Fällen eine ausreichend exakte Schätzung des Gesamt-IQ durch die Kurzform möglich ist. Wichtige Fehlerquellen (Extremwerte, heterogene Testprofile) werden diskutiert.

Epilepsy surgery outcome in children with focal epilepsy due to tuberous sclerosis complex

Tuberous sclerosis complex (TSC) is frequently associated with focal epilepsy due to cerebral tubers. Seizures are the first symptoms in most patients with brain involvement. These epilepsies are frequently severe, drug-resistant and may have a negative impact on the child's global development. Although most epilepsies are multicentric, these patients may be candidates for epilepsy surgery, if it is possible to determine a leading epileptogenic tuber. Nine patients with TSC were examined with long-term video-EEG monitoring, different neuroimaging techniques and neuropsychological tests. A main epileptogenic tuber could be identified in all of our patients. We found good correlations between neuroimaging and EEG. Surgery was performed in eight patients. Seizure outcome was good in all. Two patients became seizure-free, one patient had a single prolonged seizure five days postoperatively, four patients had a significant seizure reduction of more than 75 % and one patient had a seizure reduction of more than 50 % after surgery without additional neurologic deficits. In conclusion, patients with TSC and drug-resistant epilepsy may benefit from epilepsy surgery with reduction in frequency and severity of seizures as well as improved mental and behavioural development leading to a better quality of life. In view of recent developments in functional and metabolic imaging, primary epileptogenic lesions will be more easily detectable in patients with diffuse brain involvement in TSC and surgical treatment may be more specifically applied at an earlier age to a selected subgroup of patients with this disorder.

Proof of C4 photosynthesis without Kranz anatomy in Bienertia cycloptera (Chenopodiaceae)

Kranz anatomy, with its separation of elements of the C4 pathway between two cells, has been an accepted criterion for function of C4 photosynthesis in terrestrial plants. However, Bienertia cycloptera (Chenopodiaceae), which grows in salty depressions of Central Asian semi-deserts, has unusual chlorenchyma, lacks Kranz anatomy, but has photosynthetic features of C4 plants. Its photosynthetic response to varying CO2 and O2 is typical of C4 plants having Kranz anatomy. Lack of night-time CO2 fixation indicates it is not acquiring carbon by Crassulacean acid metabolism. This species exhibits an independent, novel solution to function of the C4 mechanism through spatial compartmentation of dimorphic chloroplasts, other organelles and photosynthetic enzymes in distinct positions within a single chlorenchyma cell. The chlorenchyma cells have a large, spherical central cytoplasmic compartment interconnected by cytoplasmic channels through the vacuole to the peripheral cytoplasm. This compartment is filled with mitochondria and granal chloroplasts, while the peripheral cytoplasm apparently lacks mitochondria and has grana-deficient chloroplasts. Immunolocalization studies show enzymes compartmentalized selectively in the CC compartment, including Rubisco in chloroplasts, and NAD-malic enzyme and glycine decarboxylase in mitochondria, whereas pyruvate, Pi dikinase of the C4 cycle is localized selectively in peripheral chloroplasts. Phosphoenolpyruvate carboxylase, a cytosolic C4 cycle enzyme, is enriched in the peripheral cytoplasm. Our results show Bienertia utilizes strict compartmentation of organelles and enzymes within a single cell to effectively mimic the spatial separation of Kranz anatomy, allowing it to function as a C4 plant having suppressed photorespiration; this raises interesting questions about evolution of C4 mechanisms.

Kranz anatomy is not essential for terrestrial C4 plant photosynthesis

An important adaptation to CO2-limited photosynthesis in cyanobacteria, algae and some plants was development of CO2-concentrating mechanisms (CCM). Evolution of a CCM occurred many times in flowering plants, beginning at least 15-20 million years ago, in response to atmospheric CO2 reduction, climate change, geological trends, and evolutionary diversification of species. In plants, this is achieved through a biochemical inorganic carbon pump called C4 photosynthesis, discovered 35 years ago. C4 photosynthesis is advantageous when limitations on carbon acquisition are imposed by high temperature, drought and saline conditions. It has been thought that a specialized leaf anatomy, composed of two, distinctive photosynthetic cell types (Kranz anatomy), is required for C4 photosynthesis. We provide evidence that C4 photosynthesis can function within a single photosynthetic cell in terrestrial plants. Borszczowia aralocaspica (Chenopodiaceae) has the photosynthetic features of C4 plants, yet lacks Kranz anatomy. This species accomplishes C4 photosynthesis through spatial compartmentation of photosynthetic enzymes, and by separation of two types of chloroplasts and other organelles in distinct positions within the chlorenchyma cell cytoplasm.

Procalcitonin as a diagnostic marker in patients with aspiration after closed head injury

BACKGROUND

Aspiration of gastric content frequently induces early onset of pneumonia in patients with impaired consciousness after closed head injury and thus worsens the prognosis. Early detection of aspiration and appropriate therapy are essential. The purpose of the study was to assess the diagnostic value of procalcitonin (ProCT) in aspiration of gastric content and to evaluate its prognostic impact in patients with closed head injury.

METHODS

Twenty-three patients with isolated closed head injury (Glasgow Coma Scale [GCS] score < or = 8) were studied. Bronchoscopy was done on admission; chest radiographs and routine laboratory examination including C-reactive protein were performed daily. ProCT was analyzed 12, 24, 36 and 72 hours after trauma using an immunoluminometric assay.

RESULTS

ProCT was higher throughout the study period in 9 patients with persistent radiological signs suspect for aspiration of gastric content and there was evidence of aspiration of gastric content during bronchoscopy on admission. Median ProCT values of 1.397 ng/ml (range, 0.372 to 8.358 ng/ml) on admission increased to 2.144 ng/ml (range, 0.716 to 6.910 ng/ml) 24 hours after trauma, and then decreased to baseline values of 1.711 ng/ml (range, 0.611 to 6.639 ng/ml) as early as 36 hours after trauma. In patients without signs of aspiration of gastric content, ProCT values did not exceed 0.418 ng/ml. Non-survivors had higher serum levels of ProCT throughout the study period.

CONCLUSION

Our findings suggest that ProCT is a useful diagnostic marker for detecting aspiration of gastric content while the prognostic value of ProCT for predicting survival after isolated closed head injury was moderate.

New observations on the secondary chemistry of world Ephedra (Ephedraceae)

For several millennia, stem extracts of Ephedra (Ephedraceae, Gnetales) have been used as folk medicines in both the Old and New World. Some species were used in treatments of questionable efficacy for venereal disease in North America during the last century. Many Eurasian species produce phenylethylamine alkaloids, mostly ephedrine and pseudoephedrine, that interact with adrenergic receptors in the mammalian sympathetic nervous system. Asian Ephedra have been used recently in the clandestine manufacture of a street drug, methamphetamine. Although ephedrine alkaloids are not detectable in New World species of Ephedra, together with Asian species they contain other nitrogen-containing secondary metabolites with known neuropharmacological activity. Many mesic and particularly xeric species worldwide accumulate substantial amounts of quinoline-2-carboxylic acids, or kynurenates, in their aerial parts. Many species of Ephedra accumulate cyclopropyl amino acid analogues of glutamate and proline in their stems and roots, and particularly in the seed endosperm. Mesic species synthesize substantial amounts of three L-2-(carboxycyclopropyl)glycine stereomers rarely seen in nature. A cyclopropyl analogue of proline with known antimicrobial activity, cis-3,4-methanoproline, is found in large amounts in the stems and seeds of many Ephedra species. The ability to synthesize cyclopropyl amino acids may be an ancestral feature in the taxon. The natural function in the taxon of these three groups of secondary compounds remains to be established.

A prospective randomized trial comparing the cuffed oropharyngeal airway (COPA) with the laryngeal mask for elective minor surgery in female patients

OBJECTIVE

The cuffed oropharyngeal airway (COPA), a modified Guedel-type airway with a cuff at the distal end, has recently been introduced into anesthetic practice. The aim of this study was to compare the COPA with the well established laryngeal mask airway (LMA). Special consideration was granted to the difficult airway.

PATIENTS AND METHODS

Two hundred and fifty-two women of ASA class I or II undergoing elective gynecological or breast surgery under general anesthesia were randomly assigned to either cuffed oropharyngeal or laryngeal mask airway management. Insertion and removal of the device, airway maintenance throughout the procedure, and postoperative course and complications were assessed.

RESULTS

A patent airway was obtained with either device in all patients. Global first-time success rates for insertion were similar in the two study groups. Initial failure of correct placement occurred more frequently in the COPA as compared to the LMA group if the interincisor gap was < 5 cm and mandibular protrusion impossible (p < 0.01). Neither thyromental distance nor Mallampati scores nor body mass index (BMI) were of relevance for insertion success. The incidence of postoperative complaints and of mucosal injuries was significantly higher with the LMA.

CONCLUSION

On the whole, high overall success and low complication rates render COPA and LMA equally suitable for routine anesthetic airway management.

Ondansetron is no more effective than supplemental intraoperative oxygen for prevention of postoperative nausea and vomiting

Supplemental oxygen maintained during and for 2 h after colon resection halves the incidence of nausea and vomiting. Whether supplemental oxygen restricted to the intraoperative period is sufficient remains unknown. Similarly, the relative efficacy of supplemental oxygen and ondansetron is unknown. We tested the hypothesis that intraoperative supplemental oxygen reduces the incidence of postoperative nausea and vomiting. Patients (n = 240) undergoing gynecological laparoscopy were given a standardized isoflurane anesthetic. After induction, they were randomly assigned to the following three groups: routine oxygen administration with 30% oxygen, balance nitrogen (30% Oxygen group), supplemental oxygen administration with 80% oxygen, balance nitrogen (80% Oxygen group), and Ondansetron 8 mg (immediately after induction), combined with 30% oxygen, balance nitrogen (Ondansetron group). The overall incidence of nausea and/or vomiting during the initial 24 postoperative h was 44% in the patients assigned to 30% oxygen and 30% in the Ondansetron group, but only 22% in those given 80% oxygen. The incidence was thus halved by supplemental oxygen and was significantly less than with 30% oxygen. There were, however, no significant differences between the 30% oxygen and ondansetron groups, or between the ondansetron and 80% oxygen groups. We conclude that supplemental oxygen effectively prevents postoperative nausea and vomiting after gynecological laparoscopic surgery; furthermore, ondansetron is no more effective than supplemental oxygen.

IMPLICATIONS

Supplemental oxygen reduces the risk of postoperative nausea and vomiting (PONV) as well or better than 8 mg of ondansetron. Because oxygen is inexpensive and essentially risk-free, supplemental oxygen is a preferable method of reducing PONV.

S(+)-ketamine for rectal premedication in children

Our purpose for this prospective, randomized, and double-blinded study was to evaluate the anesthetic efficacy of S(+)-ketamine, an enantiomer of racemic ketamine, compared with a combination of S(+)-ketamine and midazolam, and plain midazolam for rectal premedication in pediatric anesthesia. Sixty-two children, ASA physical status I and II, scheduled for minor surgery, were randomly assigned to be given rectally one of the following: 1.5 mg/kg preservative-free S(+)-ketamine, a combination of 0.75 mg/kg preservative-free S(+)-ketamine and 0.75 mg/kg midazolam, or 0.75 mg/kg midazolam. Preoperative anesthetic efficacy was graded during a period of 20 min by using a five-point scale from 1 = awake to 5 = asleep. Tolerance during anesthesia induction via face mask was graded by using a four-point scale from 1 = very good to 4 = bad. A sufficient anesthetic level (> or = 3) after rectal premedication was reached in 86% in midazolam/S(+)-ketamine premedicated children, in 75% in midazolam premedicated children, but only in 30% in S(+)-ketamine premedicated children (P < 0.05 S(+)-ketamine versus midazolam/S(+)-ketamine and midazolam groups). The incidence of side effects after rectal premedication was rare. Whereas the mask acceptance score was comparable in the three study groups, a 25% rate of complications during anesthesia induction via face was observed in the S(+)-ketamine study group (P < 0.05 versus other study groups). Our conclusions are that S(+)-ketamine for rectal premedication in the dose we chose shows a poor anesthetic effect and a frequent incidence of side effects during induction of anesthesia via face mask compared with the combination of midazolam/S(+)-ketamine and plain midazolam. Dose-response studies of S(+)-ketamine for rectal premedication in pediatric anesthesia may be warranted.

Electrical stimulation of the vestibular system prevents postoperative nausea and vomiting

BACKGROUND

Electrical stimulation of the vestibular system may prevent nausea and vomiting. We studied the influence of transcutaneous impulse stimulation in prevention of postoperative nausea and vomiting (PONV) following gynaecological surgery.

METHODS

In this randomised study 70 women undergoing elective gynaecological surgery under general anaesthesia were assigned to receive either the activated (stimulation group) or the inactivated (non-stimulation group) impulse stimulator. The stimulator comprises the stimulator itself, two negative electrodes on a headset applied over both mastoid processes and a nuchal positive electrode. The device yielded a pulse frequency of 5 Hz direct current, individually adjustable between 0.5 and 4 mA. A trapezoid stimulation of 50 ms was applied. Nausea, vomiting, dizziness and the amount of antiemetic drugs used were assessed during the first 4 h postoperatively.

RESULTS

Lower postoperative nausea scores with a lower incidence of vomiting and postoperative dizziness were found in the stimulation group. A lower amount of antiemetic drugs was needed in the stimulation group when compared to the non-stimulation group (P<0.01 between groups).

CONCLUSION

This study suggests that electrical stimulation of the vestibular system may be useful in prevention of PONV.

Single-injection paravertebral block compared to general anaesthesia in breast surgery

BACKGROUND

Breast surgery is frequently associated with post-operative nausea, vomiting, pain and painful restricted movement. Paravertebral block may be an alternative to general anaesthesia for this type of surgery. We studied the single-injection paravertebral block at the level of T4 and report a comparison of single-injection paravertebral block to general anaesthesia for breast surgery.

METHODS

After written informed consent was obtained, 86 patients were enrolled in this prospective study. Forty-four women were randomly allocated to receive a single-injection paravertebral block at the level of T4, while 42 women received general anaesthesia. The surgical procedures varied from lumpectomy (wide local excision of a tumour) to modified radical mastectomy with axillary dissection. The block was performed according to the guidelines described by Eason and Wyatt using 0.3 ml x kg(-1) (maximum dose 150 mg) of bupivacaine 0.5%. The skin and the underlying tissues were infiltrated with local anaesthetic solution two fingers (about 3 cm) from the anatomical midline and level with the cephalad end of the vertebral spine.

RESULTS

Time for performance of blocks lasted from 4 to 9 min. Recovery from anaesthesia or sedation was shortened, while postoperative pain scores (VAS), the incidence of vomiting and the requirement for analgesics were lower in the paravertebral group. Less painful restricted movement was observed in the paravertebral block group. Paravertebral block was inadequate in 6.8% of patients. Epidural spread with paraparaesis and Horner triad was assumed in one patient.

CONCLUSION

Single-injection paravertebral block at the level of T4 represents a suitable alternative to general anaesthesia in women undergoing breast surgery.

[Correlation between prognostically predicted and actually attained refraction]

BACKGROUND

In cataract surgery high quality is demanded. That is why high precision in calculation of IOL power is necessary for predicting postoperative refraction.

MATERIALS AND METHODS

In a series of 103 patients the predicted refraction--calculated by the SRK II formula for only one type of IOL (A-constant 118.9)--was compared to the received early and late (3 month) postoperative refraction.

RESULTS

The accuracy of IOL calculations in 95% was acceptable--within a range of 2 diopters. The prediction errors of extended values were only shown in cases of axial length of more than 26 millimeters.

CONCLUSIONS

The results confirm the fact that by means of SRK II formula the accuracy of IOL calculation is satisfactory in respect of predicted refraction. In eyes of elongated axial length the accuracy is limited.

Carbohydrate-deficient transferrin as a screening marker for drinking in a general hospital population

We investigated the usefulness of the laboratory marker of alcohol consumption carbohydrate-deficient transferrin (CDT) in 101 consecutively admitted patients in a surgical and internal medical ward of a hospital in a rural wine-growing area. Four major aspects were considered: the influence of liver disease, the method of expression of CDT values (relative % vs absolute units/1), level and pattern of alcohol consumption and comparison with y-glutamyl transferase (GGT). The results show that %CDT is a more valuable discriminating marker of high alcohol consumption than absolute CDT values and its usefulness in this respect is independent of changes in serum total transferrin levels, as in liver disease. Sensitivity and specificity of % CDT were 70 and 98% respectively, compared with 65 and 83% respectively for GGT.

Development and characterization of a rapid assay for bedside determinations of cardiac troponin T

BACKGROUND

The appearance of cardiac proteins in blood is the most specific and sensitive indicator of acute myocardial cell necrosis. The measurement of cardiac markers, however, is time consuming and requires sophisticated equipment. To facilitate the biochemical detection for acute myocardial cell necrosis, a whole-blood rapid assay device for cardiac troponin T detection was developed that provides a test result within 20 minutes.

METHODS AND RESULTS

Monoclonal antibody M7 is labeled with gold particles, and antibody 1B10 is labeled with biotin. Both antibodies, as well as buffer substances and detergents, are adsorbed onto paper fleeces mounted below an application well. Heparinized blood (160 microL) applied to this well solubilizes the dry chemistry reagents. Blood cells are separated from plasma via a glass-fiber fleece. The immunocomplexes formed are concentrated within the reading zone by binding of the biotin-labeled antibody with streptavidine immobilized to the test device. Troponin T bound to the test device serves as a control. The detection limit of this assay is 0.18 microgram/L with a cross-reactivity with skeletal troponin T of 0.5%. In clinical analyses involving 25 healthy volunteers, 62 patients with chest pain but without myocardial ischemia, 35 patients with acute myocardial infarction, 24 patients with minor myocardial cell damage due to radiofrequency ablation, and 35 patients with unstable angina, the rapid assay was comparable to the troponin T enzyme immunoassay in regard to sensitivity and specificity.

CONCLUSIONS

This newly developed assay allows accurate, rapid, and convenient diagnosis of acute myocardial cell necrosis.

[Poly-, multiple trauma and intra-abdominal injuries]

The present work deals with the problem of abdominal injuries in polytraumatized patients. The results were obtained from a retrospective study of the records of 530 polytraumatized patients treated at the Central Hospital of the German Federal Armed Forces (Bundeswehr). In all, 193 of these patients had abdominal injuries. The overall mortality was 23.8% (n = 126): mortality among the patients with abdominal injuries was 26% (n = 50). Abdominal injuries alone led to death in 9.1% (n = 1), but mortality increased to 18.4% when at least one extra-abdominal injuries was also present. A combination of abdominal injuries and two or more extra-abdominal lesion led to a mortality rate of 27%. Mortality was found to be age- and sex-related: in young children and patients over 55 years (especially those around 70) mortality was 33.3%-72%. Among the cases with fatal outcome there was a female-to-male ratio of 3:2. The most common causes of death were: hemorrhage shock (62.3%), head injuries (37.7%), septicemia (8.1%), pneumonia, and ARDS (5.4% each). Within the last eight years we have used the following supplementary examination methods: computed tomography, peritoneal lavage, and ultrasonography. The retrospective study has shown that CT is not the examination of choice. The reliability with lavage and ultrasonography was approximately the same, but lavage was found to be more dangerous. Therefore, we abandoned lavage and used sonography only. However, we are of the opinion that any surgeon should use the examination method that has yielded the best results for him or her, to ensure the best possible outcome for the patient.

A water-soluble form of porin from the mitochondrial outer membrane of Neurospora crassa. Properties and relationship to the biosynthetic precursor form

Mitochondrial porin, the outer membrane pore-forming protein, was isolated in the presence of detergents and converted into a water-soluble form. This water-soluble porin existed under nondenaturing conditions as a mixture of dimers and oligomers. The proportion of dimers increased with decreasing porin concentration during conversion. Water-soluble porin inserted spontaneously into artificial bilayers as did detergent-solubilized porin. Whereas the latter form had no specific requirements for the lipid composition of the bilayer, water-soluble porin inserted only into membranes containing a sterol, and only in the presence of very low concentrations of Triton X-100 (0.001% w/v) in the solution bathing the bilayer. The channels formed by water-soluble porin were indistinguishable from those formed by detergent-purified porin with respect to specific conductance and voltage dependence of conductance. Water-soluble porin bound tightly in a saturable fashion to isolated mitochondria. The bound form was readily accessible to added protease, indicating its presence on the mitochondrial surface. The number of binding sites was in the range of 5-10 pmol/mg of mitochondrial protein. Water-soluble porin apparently binds to a site on the assembly pathway of the porin precursor, since mitochondria whose binding sites were saturated with the water-soluble form did not import porin precursor synthesized in a cell-free system.

Biosynthesis of mitochondrial porin and insertion into the outer mitochondrial membrane of Neurospora crassa

Mitochondrial porin, the major protein of the outer mitochondrial membrane is synthesized by free cytoplasmic polysomes. The apparent molecular weight of the porin synthesized in homologous or heterologous cell-free systems is the same as that of the mature porin. Transfer in vitro of mitochondrial porin from the cytosolic fraction into the outer membrane of mitochondria could be demonstrated. Before membrane insertion, mitochondrial porin is highly sensitive to added proteinase; afterwards it is strongly protected. Binding of the precursor form to mitochondria occurs at 4 degrees C and appears to precede insertion into the membrane. Unlike transfer of many precursor proteins into or across the inner mitochondrial membrane, assembly of the porin is not dependent on an electrical potential across the inner membrane.

Purification and characterisation of a pore protein of the outer mitochondrial membrane from Neurospora crassa

The major protein of the outer mitochondrial membrane of Neurospora was purified. On dodecylsulfate-containing gels it displayed a single band with an apparent molecular weight of 31 000. Reconstitution experiments with artificial lipid bilayers showed that this protein forms pores. Pore conductance was dependent on the voltage across the membrane. The protein inserted into the membrane in an oriented fashion, the membrane current being dependent on the sign of the voltage. Single pore conductance was 5nS, suggesting a diameter of 2 nm of the open pore. This mitochondrial protein shows a number of similarities to the outer membrane porins of gram-negative bacteria.

[Ultrasound misdiagnosis of gallbladder concrements in "phrygian cap" deformity (author's transl)]

Gallbladder septa, for example, in "phrygian cap" deformity, may in rare cases lead to a misdiagnosis of gallbladder stones when B-mode ultrasound with gray scale is used. Among 4,000 upper abdominal ultrasound examinations which included the gallbladder one such case was observed. In view of the frequency of septated gallbladders (about 15%) this, although very rare, cause of false-positive diagnosis of stone should be taken into consideration when interpreting ultrasound tracings.

Transport of phosphate analogues in rat-liver mitochondria

The swelling of rat liver mitochondria has been studied in isotonic ammonium salts of phosphate, thiophosphate, monofluorphosphate, difluorphosphate or in isotonic ammonium malate induced by low concentrations of the mentioned anions. The data lead to the following conclusions. 1. Phosphate, thiophosphate, and monofluorphosphate are taken up by the mitochondria, whereas difluorphosphate is not, indicating that the substrate of the transporter represents the divalent anion HPO24- and not H2PO4-. 2. Thiophosphate, monofluorphosphate and phosphate, but not difluorphosphate induce the swelling of mitochondria in isotonic ammonium malate, only after a lag phase. The length of the lag phase depends on the concentration of inducing anion and pH. This phenomena cannot be explained by the current concept of two independent phosphate-transporting systems in mitochondria.

[The problem of functional achlorhydria]

It was examined whether in anatomically intact specific adenic parenchyma of the gastric mucosa achlorhydria can persist after maximal stimulation or whether there is support to the conception of functional achlorhydria ("functional anacidity") furthermore. Relating to the anatomic structure of the gastric mucosa secretion of chloric acid was studied after submaximal and maximal stimulation in 101 cases. It was shown that there is no correlation between the morphology and the secretion of chloric acid in anatomically intact gastric mucosa after submaximal stimulation. In 18 cases out of 28 only the secretion of acid was in correspondence to the histological condition. In two cases out of 37 with atrophic gastric mucosa diverging results were found. After maximal stimulation with histamine chloride and pentagastrine one out of two cases with histologically intact mucosa showed normochlorhydria after seven days, whereas the second case remained achlorhydric. These results must be interpreted as functional achlorhydria. Submaximal stimulation of gastric secretion as it is practised today does not allow corresponding consequences concerning the morphological condition of the gastric mucosa. Discrepant results are found especially in histologically normal mucosa. There is more congruence in atrophic gastric mucosa.