3D-exoscopic microlaryngoscopy in phonosurgery for glottic insufficiency

PURPOSE

We hypothesized that using a 3D-exoscope (3Dex) in microlaryngoscopic phonosurgery is non-inferior to using a standard operating microscope (OM). To compare the above, we utilized a 3Dex and an OM for microlaryngoscopic vocal fold augmentation with autologous fat in patients with glottic insufficiency and compared the procedure itself and the long-term impact of vocal fold augmentation on subjective and objective voice parameters in both groups.

METHODS

36 patients with glottic insufficiency received microlaryngoscopic laryngeal augmentation with autologous fat. A 3Dex was utilized in 24 cases for visualization and compared to twelve cases in which an OM was used. Voice parameters were evaluated over a period of twelve months.

RESULTS

Comparison of operation time and voice parameters between the 3Dex and OM groups did not reveal significant differences. Significant improvement of mean voice quality in all parameters excluding roughness was observed at 3 and 6 months followed then by a slight decrease of voice quality parameters between the 6 and 12 months interval in both groups.

CONCLUSION

Our findings indicate no difference concerning operation time and outcome between the use of a 3Dex and an OM in phonosurgery. Our results highlight a significant voice improvement after vocal fold augmentation with autologous fat in glottic insufficiency mediated dysphonia. The smaller viewing system, better ergonomics for the primary surgeon and the assistant and a direct view for the entire surgical team make a 3Dex an interesting alternative for visualization in microlaryngoscopic phonosurgery.

Pre-stroke socioeconomic status predicts upper limb motor recovery after inpatient neurorehabilitation

BACKGROUND

Lower socioeconomic status (SES) is associated with higher mortality rates and the likelihood of receiving less evidence-based treatment after stroke. In contrast, little is known about the impact of SES on recovery after discharge from inpatient rehabilitation. The aim of this study was to investigate the influence of SES on long-term recovery after stroke.

PATIENTS AND METHODS

In a prospective, observational, multicentre study, inpatients were recruited towards the end of rehabilitation. The 12-month follow-up focussed on upper limb motor recovery, measured by the Fugl-Meyer score. A clinically relevant improvement of ≥5.25 points was considered recovery. Patient-centric measures such as the Patient-reported Outcomes Measurement Information System-Physical Health (PROMIS-10 PH) provided secondary outcomes. Information on schooling, vocational training, income and occupational status pre-stroke entered a multidimensional SES index. Multivariate logistic regression models calculating odds ratios (ORs) and corresponding confidence intervals (CIs) were applied. SES was added to an initial model including age, sex and baseline neurological deficit. Additional exploratory analyses examined the association between SES and outpatient treatment.

RESULTS

One hundred and seventy-six patients were enrolled of whom 98 had SES and long-term recovery data. Model comparisons showed the SES-model superior to the initial model (Akaike information criterion (AIC): 123 vs. 120, Pseudo R²: 0.09 vs. 0.13). The likelihood of motor recovery (OR = 17.12, 95%CI = 1.31; 224.18) and PROMIS-10 PH improvement (OR = 20.76, 95%CI = 1.28; 337.11) were significantly increased with higher SES, along with more frequent use of outpatient therapy (p = .02).

CONCLUSIONS

Higher pre-stroke SES is associated with better long-term recovery after discharge from rehabilitation. Understanding these factors can improve outpatient long-term stroke care and lead to better recovery.KEY MESSAGEHigher pre-stroke socioeconomic status (SES) is associated with better long-term recovery after discharge from rehabilitation both in terms of motor function and self-reported health status.Higher SES is associated with significantly higher utilization of outpatient therapies.Discharge management of rehabilitation clinics should identify and address socioeconomic factors in order to detect individual needs and to improve outpatient recovery. Article registration: clinicaltrials.gov NCT04119479.

[Is Flying or Diving risky after cochlear implantation? Examination in a pressure chamber]

OBJECTIVE

 Complications after cochlear implantation are relatively rare but patients are asked to follow certain behavioral rules. Until now there is no evidence if pressure changes that occur during flying and diving are safe for patients after cochlear implantation. For example, no recommendation exists for SCUBA- diving activities.

MATERIALS AND METHODS

 In a hypo-/hyperbaric pressure chamber patients after cochlear implantation were exposed to a standardized profile of decompression and compression simulating a flight in a common airplane and a dive. Pre and after the exposure in the pressure chamber, ENT examination and a control of impedances of the cochlear implant were performed. Additionally, patients filled in a questionnaire about complaints they had experienced in the pressure chamber or after.

RESULTS

 A total of 11 subjects (17 ears with CI) were examined in the pressure chamber. 2/3 of the subjects stated that they had slight complaints during the examination. Only in one patient the measurement needed to be stopped due to pain. Seven patients showed a vascular injection of the malleus in ear microscopy. In none of the patients there was a subjective change in hearing after the examination. Objective measurements of the impedance did not show relevant changes.

CONCLUSION

 The exposure of cochlear implanted patients to overpressure and underpressure in a pressure chamber did not result in any significant deviation of the impedances, so that no further adjustment was necessary. Since there are no certified in vivo studies on pressure changes while diving and flying with a cochlear implant, further studies are required in order to be able to adequately advise CI patients about diving and flying.

Frequency-specific Animal Sound Test (FAST) 4: A valid method for hearing screening

OBJECTIVES

It is essential to monitor hearing status in children not only as a mandatory requirement during universal newborn hearing screening (UNHS), but also later during preschool and school-age development. The present study considers the appropriateness of the Frequency-specific Animal Sound Test (FAST4) for use in children between the ages of 2.5 and 10 years; the comparability of hearing thresholds determined using FAST4 and those measured by pure tone audiometry (PTA); and the clinical and diagnostic utility of FAST4 in a variety of pediatric settings.

METHODS

322 children aged 2.6-14.1 years and 41 adults were tested with FAST4. Four animal sounds were presented via headphones and a hearing threshold was determined for the high and low frequency range. In addition, the hearing threshold of each child was measured by PTA.

RESULTS

Results were analyzed from 156 normal-hearing and hearing-impaired children, mostly above the age of 4 years. In general, FAST4 yielded hearing levels comparable with those from PTA in children and in adults. FAST4 frequently had to be halted prematurely in children under 4 years old.

CONCLUSIONS

FAST4 is a strong candidate for use as an instrument for preschool hearing screening and offers several advantages over other hearing tests. FAST4 permits simple, swift and efficient determination of the hearing threshold and the test can be administered by staff without specialist training. A number of improvements have already been integrated into the successor model known as mFAST.

[Subcutaneous Taenia crassiceps-cysticercosis in a dog with Cushing's syndrome]

A male, 12-year-old Cairn terrier suffering from Cushing's syndrome with two therapy-resistant inflammatory subcutaneous lesions was examined pathomorphologically and parasitologically. Within the subcutaneous tissue, there was a suppurative to necrotizing and histiocytic inflammation present with the formation of caverns. Intralesional whitish-grey cysts with a diameter of 1-4 mm were detected. Molecular investigations of the cysts confirmed the preliminary morphological identification as Cysticercus longicollis. The adenohypophysis showed an infiltrative growing carcinoma. Cysticercus longicollis is the metacestode of Taenia (T.) crassiceps, a tapeworm of foxes and coyotes. Small rodents are typical intermediate hosts, in which the metacestode develops within the body cavities as well as in the subcutis. Subcutaneous cysticercosis after infection with eggs of T. crassiceps is also described in different domestic animal species and in humans, who represent aberrant intermediate hosts. Immunosuppression due to Cushing's syndrome, probably caused by the tumor of the adenohypophysis, may have played a role in the pathogenesis of the present case.

Transfection of short-interfering RNA silences adhesion molecule expression on cardiac microvascular cells

BACKGROUND

Acute rejection reactions and the development of graft arterial disease are serious limitations after transplantation. Both are connected to the expression of adhesion molecules on the activated microvascular endothelium of the allograft.

METHODS

siRNA-mediated silencing of ESELE, ICAM-1, and VCAM-1 on human cardiac microvascular cells (HCMEC) was investigated in order to inhibit leukocyte-endothelial interactions. HCMEC were investigated for the time-dependent expression of ESELE, ICAM-1, and VCAM-1 after TNF-α stimulation and for siRNA mediated suppression using a nonviral transfecting approach. Furthermore, the effects of siRNA transfection on leukocyte binding to the endothelium were analyzed.

RESULTS

Transfection with siRNA induced a significant suppression of adhesion molecule expression, regardless of whether there had been a prior single or cocktail transfection of the sequences ( P < 0.05). The quantity of attaching leukocytes was significantly reduced after an equal silencing of adhesion molecules ( P < 0.05).

CONCLUSIONS

This investigation demonstrates that liposomal transfection of HCMEC with specific siRNA sequences is capable of both repressing adhesion molecule expression and of reducing subsequent leukocyte-endothelial actions.

Veins are no arteries: even moderate arterial pressure induces significant adhesion molecule expression of vein grafts in an ex vivo circulation model

AIM

Coronary artery bypass grafting (CABG) is a standard procedure for treatment of coronary heart disease. Eighty percent of all CABGs are performed with venous grafts which then get exposed to an arterial pressure after surgery. This widely used procedure, however, is complicated by the development of alterations in the vein graft wall, leading to a decreased patency rate and graft failure. This study enlightens the influence of an even moderate arterial pressure on the gene expression of adhesion molecules in venous grafts which play a decisive role for the early induction of atherogenesis.

METHODS

Segments of porcine vena jugularis and arteria carotis were mounted in a simulated bypass circuit and subjected to pulsatile flow. Vessel segments were examined for adhesion molecule expression with quantitative real-time - polymerase chain reaction (qRT-PCR) and adherence of leukocytes was observed by confocal laser scanning microscopy and scanning electron microscopy.

RESULTS

Veins grafts subjected to an even moderate arterial pressure showed a 14-fold increase of ICAM-1 expression already after 4 hours. An arterial pressure of around 100/80 mmHg was enough to stimulate the adhesion molecule expression Furthermore it led to a 9-fold increase of leukocyte adhesion to the venous endothelium, but, in contrast this was not the case in arteries.

CONCLUSION

This study showed, that already 100 mmHg upregulates the expression of several adhesion molecules in pig veins followed by increased adhesion of leukocytes. Therefore, our data demonstrate the advantage of arteries for CABG, and that new therapeutic strategies are urgently necessary to protect vein grafts either physically or pharmacologically if arteries are not available for CABG.

Mothers’ experiences of labour in a tertiary care hospital

The purpose of the study was to explore and describe experiences of mothers during childbirth in a tertiary hospital in the Limpopo Province. This was achieved through a qualitative research study which was exploratory, descriptive, contextual and inductive in nature. A sample of 24 mothers participated in this study. Data obtained from unstructured in-depth interviews were analysed according to the protocol by Tesch (1990, cited in Cresswell, 1994:155). Five themes were identified, namely mutual participation and responsibility sharing, dependency and decision-making; information sharing and empowering autonomy and informed choices; open communication and listening; accommodative/non-accommodative midwifery actions; and maximising human and material infrastructure. The themes indicated experiences that foster or promote dependency on midwifery care. Guidelines on how to transform this dependency into a mother-centered care approach during childbirth are provided. Opsomming Die doel van die studie was om moeders se belewenis van kindergeboorte in ’n tersiêre hospitaal in die Limpopo Provinsie te verken en te beskryf. Dit is gedoen deur middel van kwalitatiewe navorsing wat verkennend, beskrywend, en kontekstueel was. ‘n Steekproef van 24 moeders het aan die studie deelgeneem. Inligting is verkry deur middel van ongestruktureerde in-diepte onderhoude. Hierdie inligting is geanaliseer aan die hand van Tesch (1990: aangehaal in Creswell, 1994:155) se protokol. Die volgende kategorieë is geïdentifiseer, wedersydse deelname en gedeelde verantwoordelik- hede, afhanklikheid en besluitneming, deel van inligting, bemagtiging tot outonomie en ingeligte keuse, oop kommunikasie en luister, akkommoderende/nie-akkommoderende vroedvrou-aksies en bevordering van menslike en materiële infrastrukture. Die resultate van die onderhoude het belewenisse blootgelê wat dui op die bevordering van afhanklikheid in vroedvrouversorging. Riglyne om hierdie afhanklikheid te verander in ‘n moedergesentreerde benadering word verskaf.

Functional magnetic resonance imaging of human olfaction

Olfaction is our basic sense phylogenetically and embryologically. Little is known, however, about how the human brain encodes the quality of odors, odor-associated memories, and emotions. Olfactory information is projected from the olfactory bulb to the primary olfactory cortex, which is composed of the anterior olfactory nucleus, the olfactory tubercle, the piriform cortex, the amygdala, the periamygdaloid region, and the entorhinal cortex. From there, the primary olfactory cortex projects to secondary olfactory regions including the hippocampus, ventral striatum and pallidum, hypothalamus, thalamus, orbitofrontal cortex, agranular insular cortex, and cingulate gyrus. Functional MR studies using olfactory stimuli as paradigms show activation of many of these areas and can advance our understanding of odor perception in humans.

Simultaneous immunomagnetic CD34+ cell selection and B-cell depletion in peripheral blood progenitor cell samples of patients suffering from B-cell non-Hodgkin's lymphoma

The reduction of residual tumor cells is one of the main targets of leukapheresis product (LP) processing. Immunomagnetic enrichment/selection of CD34+ progenitor cells (Baxter Isolex 300i) can achieve a reduction of contaminating B-cells of approximately 2-3 logs in B-cell non-Hodgkin's lymphoma patients. Specific release of the enriched CD34+ cells (stem cell releasing agent PR34+; Baxter) and the use of antibody-coated immunobeads targeted against B-cell markers (CD10, CD19, CD20, CD22, CD23, and CD37) during this procedure allows the GMP-like simultaneous capture of residual B cells within a closed system. This combination of two purging techniques enhances the B-cell depletion capacity up to 4.5 logs. By performing 10 clinical-scale purging procedures, we could show that the simultaneous immunomagnetic purging method is easy to perform and highly efficient. We evaluated B-cell log depletion by flow cytometry for cases with marker-positive cells detectable before and after the purging procedure. The mean reduction of B-cells in these cases was 3.5 logs; the mean CD34+ cell yield and purity were 47 and 92%. Using three LPs, we tested the procedure on a modified Baxter Isolex 300i device with software adaptations for this procedure (software version 2.0) in direct comparison with CD34+ cell selection only, using the former version (version 1.12). The CD34+ cell yield was 49% (40-54%) for the CD34+ cell selection and 51% (19-72%) for simultaneous double selection. The mean purity was 96% for CD34+ cell selection and 98% for simultaneous double selection. B-cell depletion was 1.9 logs for CD34+ cell selection, and after simultaneous double selection, the B-cell content was decreased by 3.7 log steps (P = 0.0495). Clinical application of double-purged cells has not prolonged the hematopoietic recovery times after high-dose therapy as compared with nonpurged peripheral blood progenitor cell autotransplants. In conclusion, we could show that the simultaneous double selection protocol developed leads to a highly increased B-cell purging efficacy when compared with CD34+ cell selection without any negative effects regarding CD34+ cell yield and engraftment times after high-dose therapy.

Phylogeography of the bullhead Cottus gobio (Pisces: Teleostei: Cottidae) suggests a pre-pleistocene origin of the major central European populations

The bullhead Cottus gobio is a small, bottom-dwelling fish consisting of populations that have not been subject to transplantations or artificial stocking. It is therefore an ideal model species for studying the colonization history of central European freshwater systems, in particular with respect to the possible influences of the Pleistocene glaciation cycles. We sampled Cottus populations across most of its distribution range, with a special emphasis on southern Germany where the major European drainage systems are in closest contact. Mitochondrial D-loop sequencing of more than 400 specimens and phylogenetic network analysis allowed us to draw a detailed picture of the colonization of Europe by C. gobio. Moreover, the molecular distances between the haplotypes enabled us to infer an approximate time frame for the origin of the various populations. The founder population of C. gobio stems apparently from the Paratethys and invaded Europe in the Pliocene. From there, the first colonization into central Europe occurred via the ancient lower Danube, with a separate colonization of the eastern European territories. During the late Pliocene, one of the central European populations must have reached the North Sea in a second step after which it then started to colonize the Atlantic drainages via coastal lines. Accordingly, we found very distinct populations in the upper and lower Rhine, which can be explained by the fact that the lower Rhine was disconnected from the upper Rhine until approximately 1 million years ago (Ma). More closely related, but still distinct, populations were found in the Elbe, the Main and the upper Danube, all presumably of Pleistocene origin. Intriguingly, they have largely maintained their population identity, despite the strong disturbance caused by the glaciation cycles in these areas. On the other hand, a mixing of populations during postglacial recolonization could be detected in the lower Rhine and its tributaries. However, the general pattern that emerges from our analysis suggests that the glaciation cycles did not have a major impact on the general population structure of C. gobio in central Europe.

Reconstitution of the cellular immune response after autologous peripheral blood stem cell transplantation in patients with non-Hodgkin's lymphoma

Peripheral blood stem cell (PBSC) transplants may be depleted of lymphoid progenitors, thereby disabling the cellular immune response against viral pathogens after autologous PBSC transplantation (PBSCT). To monitor the cellular immune reconstitution after autologous PBSCT, we investigated the cytolytic activity (CLA) of peripheral blood T lymphocytes against Epstein-Barr virus (EBV) in 13 patients with non-Hodgkin's lymphoma or multiple myeloma. The individual EBV-directed CLA (EBV-CLA) was determined by calculating the number of cytolytic effector cells in 106 T cells needed to lyse 25% of autologous EBV-transformed B-lymphoblastoid cells, expressed as lytic units (LU25). During the first 6 months after PBSCT, the EBV-CLA was only 14.6% of the response of healthy controls (median 4. 8 vs. 32.9 LU25). Thereafter, the EBV-CLA increased to 28.15 LU25 (median) or 86% of healthy controls. Monthly follow-up analyses in five selected patients showed that the EBV-CLA was barely detectable at 4 weeks and recovered at 8-12 weeks after PBSCT in four out of five patients. Effector cells consisted mostly of CD8-positive T lymphocytes, with small CD4- and CD3/CD56-positive lymphocyte fractions. These results suggest that the reconstitution of the cellular immune response against EBV takes 8-12 weeks after autologous PBSCT.

Smooth pursuit performance in families with multiple occurrence of schizophrenia and nonpsychotic families

BACKGROUND

Eye tracking dysfunction (ETD) has been put forward as a trait marker for biological susceptibility to schizophrenia with the hope of identifying a link to specific cerebral lesions.

METHODS

Eye movements were recorded using infrared oculography in 8 families (67 members) showing multiple occurrence of schizophrenia and in 9 nonpsychotic families (80 members). Triangle wave stimuli at 15 degrees/s and 30 degrees/s were used and gains (eye velocity/target velocity), rates and amplitudes of different saccade categories (catch-up, back-up, anticipatory saccades, and squarewave-jerks) were determined.

RESULTS

In the relatives, the same deficit in maintenance of smooth pursuit performance was found as was seen in the schizophrenic patients. This deficit, which was not observed in the nonpsychotic families, consisted of lower gains for leftward as compared to rightward pursuit. This was emphasized most clearly at 30 degrees/s and was associated with an excess of catch-up saccades in the schizophrenic patients, whereas in the relatives a tendency to exhibit more and larger anticipatory saccades was observed.

CONCLUSIONS

The results confirm the hypothesis that eye-tracking dysfunction is a phenotypic marker for genetic liability to schizophrenia. Neurophysiologically, a cerebral dysfunction which includes one or more of the oculomotor centers can be assumed in subjects who carry a genetic susceptibility to schizophrenia.

CD40-activated B-cell chronic lymphocytic leukemia cells for tumor immunotherapy: stimulation of allogeneic versus autologous T cells generates different types of effector cells

Although spontaneous remissions may rarely occur in B-cell chronic lymphocytic leukemia (B-CLL), T cells do generally not develop a clinically significant response against B-CLL cells. Because this T-cell anergy against B-CLL cells may be caused by the inability of B-CLL cells to present tumor-antigens efficiently, we examined the possibility of upregulating critical costimulatory (B7-1 and B7-2) and adhesion molecules (ICAM-1 and LFA-3) on B-CLL cells to improve antigen presentation. The stimulation of B-CLL cells via CD40 by culture on CD40L expressing feeder cells induced a strong upregulation of costimulatory and adhesion molecules and turned the B-CLL cells into efficient antigen-presenting cells (APCs). CD40-activated B-CLL (CD40-CLL) cells stimulated the proliferation of both CD4(+) and CD8(+) T cells. Interestingly, stimulation of allogeneic versus autologous T cells resulted in the expansion of different effector populations. Allogeneic CD40-CLL cells allowed for the expansion of specific CD8(+) cytolytic T cells (CTL). In marked contrast, autologous CD40-CLL cells did not induce a relevant CTL response, but rather stimulated a CD4(+), Th1-like T-cell population that expressed high levels of CD40L and released interferon-gamma in response to stimulation by CD40-CLL cells. Together, these results support the view that CD40 activation of B-CLL cells might reverse T-cell anergy against the neoplastic cell clone, although the character of the immune response depends on the major histocompatibility complex (MHC) background on which the CLL or tumor antigens are presented. These findings may have important implications for the design of cellular immunotherapies for B-CLL.

Unexpected metal ion requirements specific for catalysis of the branching reaction in a group II intron

The splicing process catalyzed by group II intron ribozymes follows the same two-step pathway as nuclear pre-mRNA splicing. In vivo, the first splicing step of wild-type introns is a transesterification reaction giving rise to a branched lariat intron-3'-exon intermediate characteristic of this splicing mode. In the wild-type introns, the ribozyme core and the substrate intron-exon junctions are carried by the same precursor molecule, making it difficult to distinguish between RNA folding and catalysis under normal splicing reactions. To characterize the catalytic step of the first transesterification reaction, we studied the reversal of this reaction, reverse branching. In this reverse reaction, the excised lariat intron and the substrate 5'-exon can be preincubated and folded separately, allowing the measure of the catalytic rate of the reaction. To measure the catalytic rate of the second splicing step, purified lariat intron-3'-exon intermediate molecules were preincubated and folded prior to the addition of 5'-exon. Conditions could be found where chemistry appeared rate limiting for both catalytic steps. Study of the metal ion requirements under these conditions resulted in the unexpected finding that, for the intron studied, substitution of magnesium ions by manganese ions enhanced the rate of the first transesterification reaction by two orders of magnitude but had virtually no effect on the second transesterification reaction or the 5' splice site cleavage by hydrolysis. Finally, the catalytic rates measured under optimal conditions for both splicing steps were faster by three orders of magnitude in the branching pathway than in the hydrolytic pathway.

Traditional birth attendants in South Africa: professional midwives' beliefs and myths

It is necessary to establish in a scientific way what the knowledge of midwives regarding TBAs are, because misconceptions can very often lead to a negative attitude. The objective of the research was to determine what the practices of traditional birth attendants are regarding antenatal, intrapartum, and postnatal care according to professional midwives. An exploratory research design was used, where qualitative research methods were used to explore the above-mentioned aspects about the traditional birth attendant in certain communities in South Africa. Open-ended questionnaires were used to determine how midwives see the role of the TBA. Content analysis has been used to analyse the responses of the professional midwives. The role of the TBA according to the midwives can be summarised as follows, she is a middle aged or elderly lady with no formal training, who acquired her skills through experience. She attends to women during pregnancy, labour and the postnatal period in different ways that have been used by the TBA are mainly herbs that facilitate a quick delivery, or others that cause bleeding of the uterus postnatally. Other TBAs use no medicine. All the functions identified by the midwives were compared with literature about the role of TBAs in Africa. The majority of functions identified by midwives were found in the literature. The majority of professional midwives thought it a good idea to have TBAs who have undergone some form of training in order to improve their standard of practice and to teach them the early symptoms of complications. Implications for future practice will therefore be, amongst others, to start with training programmes for TBAs. An assessment in each community of the best way to do so, should first be done.

Crystal structure of domain E of Thermus flavus 5S rRNA: a helical RNA structure including a hairpin loop

The synthetic RNA fragment 5'-CUGGGCGG(GCGA)CCGCCUGG (nucleotides in parentheses indicate the loop region) corresponds to the natural sequence of domain E from nucleotides 79-97 of the Thermus flavus 5S rRNA including a hairpin loop. The RNA structure determined at 3.0 A and refined to an R-value of 24.1% also represents the first X-ray structure GNRA tetraloop. The loop is in distinctly different conformation from other GNRA tetraloops analyzed by NMR. The conformation of the two molecules in the asymmetric unit is influenced and stabilized by specific intermolecular contacts. The structural features presented here give evidence for the ability of RNA molecules to adapt to specific environments.

Influence of substrate structure on in vitro ribozyme activity of a group II intron

Substrate sequences surrounding catalytic RNAs but not involved in specific, conserved interactions can severely interfere with in vitro ribozyme activity. Using model group II intron precursor transcripts with truncated or randomized exon sequences, we show that unspecific sequences within the 5' exon are particularly prone to inhibit both the forward and the reverse first splicing step (branching). Using in vitro selection, we selected efficient 5' exons for the reverse branching reaction. Precursor RNAs carrying these selected 5' exons reacted more homogeneously and faster than usual model precursor transcripts. This suggests that unfavorable structures induced by the 5' exon can introduce a folding step that limits the rate of in vitro self-splicing. These results stress how critical is the choice of the sequences retained or discarded when isolating folding domains from their natural sequence environments. Moreover, they suggest that exon sequences not involved in specific interactions are more evolutionarily constrained with respect to splicing than previously envisioned.

Assessment and characterization of the cytolytic T lymphocyte response against Epstein-Barr virus in patients with non-Hodgkin's lymphoma after autologous peripheral blood stem cell transplantation

The cytolytic T lymphocyte (CTL) response has often been used to assess the reconstitution of T cell function after allogeneic or autologous bone marrow transplantation (BMT). Less is known, however, about the reconstitution of the CTL response after peripheral blood stem cell transplantation (PBSCT). Therefore, we investigated the CTL response against Epstein-Barr virus (EBV) of patients undergoing autologous PBSCT. CTLs of six patients with relapsed non-Hodgkin's lymphoma and multiple myeloma were established before and at different times after PBSCT by in vitro stimulation of peripheral blood lymphocytes with autologous EBV-transformed lymphoblastoid cell lines (LCLs). The efficiency of T cell priming by LCLs was assessed at the time of initiation of CTL lines; the proliferative response was strongly reduced during the first 4 months and increased 5 months or more following PBSCT. Cytolytic activity was measured after three or four restimulations of CTLs. All patients investigated had a detectable EBV-specific CTL response which was poor during the first weeks after transplantation, accompanied by a strong non-MHC-restricted cytotoxic activity and a high proportion of CD56-positive T cells. Five or more months after PBSCT, a specific CTL response against EBV was seen which was similar to the situation prior to PBSCT, while the unspecific cytotoxic response decreased. Blocking experiments with monoclonal anti-CD3, anti-CD8 or anti-MHC I antibodies resulted in substantial inhibition of autologous LCL lysis, whereas anti-CD4 or anti-MHC II antibodies had no effect. Finally, autologous PHA blasts of a patient with the HLA haplotype A1/9+, B5/8+, Cw4/7+, were loaded with various EBNA-derived nonapeptides known to be presented by HLA B8 or A11, and exposed to autologous, EBV-directed CTLs. Specific lysis by CTLs only occurred with HLA B8-, but not with HLA A11-restricted nonapeptides. This demonstrated the existence of an MHC I-restricted anti-EBV CTL response after PBSCT. Taken together, the results show that the anlaysis of the EBV-directed CTL activity may serve as a surrogate marker to assess the reconstitution of the cellular immune response in patients undergoing autologous PBSCT.

Multiple regions on the Escherichia coli heat shock transcription factor sigma32 determine core RNA polymerase binding specificity

We have analyzed the core RNA polymerase (RNAP) binding activity of the purified products of nine defective alleles of the rpoH gene, which encodes sigma32 in Escherichia coli. All mutations studied here lie outside of the putative core RNAP binding regions 2.1 and 2.2. Based on the estimated K(s)s for the mutant sigma and core RNAP interaction determined by in vitro transcription and by glycerol gradient sedimentation, we have divided the mutants into three classes. The class III mutants showed greatly decreased affinity for core RNAP, whereas the class II mutants' effect on core RNAP interaction was only clearly seen in the presence of sigma70 competitor. The class I mutant behaved nearly identically to the wild type in core RNAP binding. Two point mutations in class III altered residues that were distant from one another. One was found in conserved region 4.2, and the other was in a region conserved only among heat shock sigma factors. These data suggest that there is more than one core RNAP binding region in sigma32 and that differences in contact sites probably exist among sigma factors.

Gene transfer of the costimulatory molecules B7-1 and B7-2 into human multiple myeloma cells by recombinant adeno-associated virus enhances the cytolytic T cell response

Gene transfer of the costimulatory molecules B7-1 and B7-2 induces a potent antitumor immune response in a variety of tumor models. B cell neoplasms including multiple myeloma (MM) often show little or no expression of B7 antigens; they are therefore a potential target for this approach. To increase the expression of human B7 genes in MM cells, both genes and the neomycin phosphotransferase gene were packaged into recombinant adeno-associated virus vectors (rAAV). The resulting recombinant viruses rAAV/B7-1, rAAV/B7-2 and rAAV/Neo were used to transduce the MM cell lines LP-1 and RPMI 8226. This allowed the transduction of up to 80% of LP-1 cells 4 days after infection with purified rAAV particles. The response of human allogeneic T cells to rAAV/B7-1 and rAAV/B7-2 transduced, gamma-irradiated LP-1 cells was assessed by [3H]thymidine incorporation, by RT-PCR-based detection of immunostimulatory cytokine transcripts and by ELISA quantification of cytokines in the supernatant. Stimulation of T cells with rAAV/B7-1 or rAAV/B7-2 transduced LP-1 cells resulted in an up to 10-fold increase of T cell proliferation when compared with LP-1 cells transduced with rAAV/Neo. Similar results were obtained with RPMI 8226 cells. Both rAAV/B7-1 and rAAV/B7-2 transduced LP-1 cells stimulated the T cell secretion of IL-2 and IFN-gamma. Furthermore, [51Cr] release assays showed that rAAV/B7-1 or rAAV/B7-2 transduced LP-1 cells induced a cytolytic T cell (CTL) response, in contrast to LP-1 cells transduced with rAAV/Neo. In all assays, the effects of rAAV/B7-1 and rAAV/B7-2 were similar. Taken together, the results show that rAAV-mediated transfer of B7 genes into MM cell lines is able to enhance the antitumor T cell response and to elicit a cytolytic T cell response.

[Torus mandibularis]

Solitary or bilateral, symptomless exostoses on the lingual surface of the mandibule are called mandibular torus. It is mainly seen in young males and has a benign clinical course. The etiopathology is not known. Both genetic and environmental factors such as the anatomy of the lower jaw are considered. Syndromes associated with facial exostoses such as Proteus syndrome or Gardner's syndrome should be clinically excluded. A 40-year-old man with exostoses of the jaw is reported. With this case report we would like to draw attention to a disease which has rarely been described in the German dermatological literature.

Production of interferon-gamma in families with multiple occurrence of schizophrenia

Dysfunction of T-cell mediated immunity, which is indicated by deficient production of interleukin-2 (IL-2) and elevated levels of the soluble interleukin-2 receptor (sIL-2R), has been consistently demonstrated in schizophrenia. Recent studies on interferon-gamma (IFN-gamma), a cytokine which is also produced by T-helper cells, have indicated a lowered production in acute schizophrenia. It is not known whether this deficit is restricted to cases of acute schizophrenia or whether it is also present in residual schizophrenia and in first degree relatives, and therefore might be associated with genetic liability to the disease. We investigated 27 individuals (schizophrenics and first degree relatives) of 6 families with multiple occurrence of schizophrenia and 27 age- and sex-matched healthy controls. The production of IFN-gamma was lowered only in the acutely ill schizophrenic individuals, when compared to both controls and first degree relatives. In the context of current knowledge, this result indicates that the production of IFN-gamma can be discussed as a marker of acute exacerbation of schizophrenia, but it is not likely to represent a phenotypic marker of a genetic trait associated with the disease.

Eye tracking dysfunction is a putative phenotypic susceptibility marker of schizophrenia and maps to a locus on chromosome 6p in families with multiple occurrence of the disease

The difficulties in defining the borders of the schizophrenia spectrum is one major source of variance in linkage studies of schizophrenia. The employment of biological markers may prove advantageous. Due to empirical evidence, eye tracking dysfunction (ETD) has been discussed to be the most promising marker for genetic liability to schizophrenia. With respect to the recent progress in genomic scans, which have pointed to the short arm of chromosome 6, we carried out a scan of the 6p21-23 region with 16 microsatellite markers to test for linkage between chromosomal markers and ETD as well as schizophrenia. We tested 5 models of inheritance of ETD and found maximum two-point lod scores of 3.51 for D6S271 and 3.44 for D6S282. By including these markers in a multipoint analysis, a lod score of 4.02 was obtained. In the case of schizophrenia, 7 models were tested; however, with non-significant results. Our findings, together with another recent linkage report, point to the possibility of a second susceptibility locus for schizophrenia which may be located centromeric to the HLA region. Also, the evidence of ETD being a susceptibility marker for schizophrenia receives further support.

Inhibition of anaphylatoxin C3a- and C5a- but not nerve stimulation- or Noradrenaline-dependent increase in glucose output and reduction of flow in Kupffer cell-depleted perfused rat livers

In isolated in situ perfused rat livers, infusion of anaphylatoxins C3a and C5a, activation peptides of the complement system, as well as stimulation of sympathetic hepatic nerves have been shown to increase hepatic glucose output and to reduce hepatic flow. These effects were mediated via an at least partially prostanoid-dependent intercellular signalling chain between nonparenchymal cells and hepatocytes. Kupffer cells have been implicated as the source of prostanoids in the anaphylatoxin-dependent signalling chain and Ito cells in the nerve stimulation-dependent signalling chain, because anaphylatoxins and noradrenaline increased prostanoid synthesis in isolated Kupffer and Ito cells, respectively. To further corroborate this hypothesis, anaphylatoxins were infused and hepatic nerves were stimulated in perfused rat livers in which Kupffer cells had been largely depleted by treatment of the animals with gadolinium chloride. Native human anaphylatoxin C3a (nhC3a) and recombinant rat anaphylatoxin C5a (rrC5a) increased prostanoid formation as well as glucose output and reduced flow in perfused rat liver. In Kupffer cell-depleted rat livers, the nhC3a- and rrC5a-mediated prostanoid formation was nearly abolished, and the increase in glucose output and the reduction of flow were reduced to between 30% and 50% (area under the curve [AUC]) of control livers. In contrast, stimulation of hepatic nerves increased glucose output and reduced flow to a similar extent in Kupffer cell-depleted livers as in control livers. These results indicate that Kupffer cells were not involved in the prostanoid-mediated nerve stimulation-dependent increase in glucose output and reduction of flow. Kupffer cells seemed, however, to be at least one major source of the anaphylatoxin-mediated prostanoid formation and, consequently, stimulation of glucose release and flow reduction in perfused liver. Because the metabolic and hemodynamic anaphylatoxin effects were not completely blocked in livers of gadolinium-treated animals, either Kupffer cells may not have been entirely eliminated, or yet another nonparenchymal cell type and mediator might be involved in the anaphylatoxin-elicited intercellular communication between nonparenchymal cells and hepatocytes.

Mirror-image RNA that binds D-adenosine

A 58-mer L-RNA ligand that binds to naturally occurring D-adenosine with a dissociation constant of 1.7 microM in solution was identified from a combinatorial library employing mirror-design. The corresponding D-RNA ligand shows identical binding affinity to L-adenosine. Reciprocal chiral specificity was also evident from ligand discrimination; the binding affinity of the L-RNA ligand for D-adenosine was 9000-fold greater than its affinity for L-adenosine and vice versa. While the D-RNA ligand was rapidly degraded in human serum, the L-RNA ligand displayed an extraordinary stability. This indicates the potential application of specifically designed L-RNA ligands as stable monoclonal antibody analogues and the development of highly stable L-ribozymes.

Mirror-design of L-oligonucleotide ligands binding to L-arginine

The high affinity and selectivity of nucleic acid ligands have clearly demonstrated that RNA can be targeted to a variety of molecules. In practice, however, the use of unmodified aptamers is impeded by the low stability of RNA in biological fluids. Here we describe the mirror-design of a stable 38-mer L-oligoribonucleotide ligand that binds to L-arginine. This L-RNA ligand was also able to bind to a short peptide containing the basic region of the human immunodeficiency virus type-1 Tat-protein. The L-RNA ligand displayed the expected stability in human serum. These findings may contribute to the identification of novel diagnostics and pharmaceuticals.

[Nurses' and patients' experience of combined health service delivery to all population groups in a hospital]

In a community hospital in Gauteng, the hospital management had, on short notice, to provide combined health services to all population groups. In the past different health services were delivered to each population group. The integration of health service delivery was a sudden change. Based on this, research questions arose, namely: how do nurses and patients experience this change, and how could they be assisted to adjust to the change. The research objectives were twofold, namely: to explore and describe nurses and patients' experience of combined health delivery to all population groups and based on the results to make recommendations to assist them with adjustment to a combined health delivery system. An exploratory, descriptive and contextual research design was followed. Trustworthiness was ensured by applying Guba's approach. Phenomenological and individual focus interviews were conducted with forty nurses and patients who were selected purposively. Field notes were written after completion of each interview. The transcribed data was analysed by using Giorgi's and Kerlinger's methods combined. Results were discussed and a literature control completed. The most important conclusions reached were: there was an insufficient administrative structure in the hospital as a result of insufficient preparation for the combined health service delivery for all population groups; the whites' perception of different populations groups is based on an ethnocentric Western approach. This led to their experience of culture shock that resulted in feelings of anger/frustration, fear and sadness; the willingness of other populations groups to adjust to combined health service delivery led to their experience of happiness; there exists communication problems between population groups because of their not being able to communicate in their own language and the difference in communication styles; the verbalised Christian viewpoint and values of whites nurses and patients are not congruent with their prejudiced perception of people of other population groups and cultures, and the different population groups do not know each other's lifeworlds and that leads to prejudices that block open communication. Several recommendations were made based on these conclusions.

Eye tracking dysfunction in families with multiple cases of schizophrenia

There is increasing evidence that the genetic predisposition for schizophrenia in families affects more individuals than those fulfilling the criteria for schizophrenia. This finding is supposed to be one of the major problems in molecular genetic schizophrenia research, especially when linkage studies are employed. Eye-tracking dysfunction (ETD), which is conceived as a possible phenotypic marker for genetic liability to schizophrenia, may offer considerable advantages. However, there is only little information from families with multiple occurrence of schizophrenia. It is still unclear whether in these families ETD aggregates with diagnoses from the schizophrenia spectrum. This first report from an ongoing study presents the results of 48 individuals from 6 multiplex families. Smooth-pursuit eye movements were recorded by infrared reflectometry and assessed by quantitative measurement techniques. Along with the high degree of psychiatric morbidity in these families, in 56.3% of the individuals ETD was assessed. Reduced mean pursuit gain was present in 39.6%. The distribution of eye-tracking dysfunction resembles the distribution of schizophrenia-related psychiatry morbidity.

Crystallization and preliminary diffraction studies of the structural domain E of Thermus flavus 5S rRNA

The ribosomal 5S RNA is an essential constituent of the large ribosomal subunit. To overcome the difficulties of crystallizing large RNA molecules such as 5S rRNAs, we decided to divide the 5S rRNA in five domains A through E to determine their structure. Recently we determined the crystal structural of the helical domain A. Here we report the crystallization of the chemically synthesized domain E of the Thermus flavus 5S rRNA. The crystal form is trigonal with unit cell dimensions: a = b = 42.80 A and c = 162.20 A. Diffraction-data to 2.8 A have been recorded and the structure solution is currently underway by means of MIR and MAD techniques.

Differences between the practice of nurses and midwives

It is often claimed by midwives that they have an unique role which is complementary to but different from the roles of other health care professionals. Most of the studies done in midwifery so far lack clarity of definition and distinction with regard to process as well as contents. It is important to describe the functions of a midwife clearly, because the absence of a clearly defined sphere of practice creates problems in the development of an appropriate curriculum. The aim of this study is to describe the unique functional activities of midwives and compare it with those of the nurse.

[The dilemma of the midwife--Part 2]

The author outlines the similarities and dissimilarities between nursing and midwifery and comes to the conclusion that the method of training midwives as part of the general nursing curriculum has advantages and disadvantages; advantages such as time, cost and manpower savings; disadvantages such as integrated course content, and lack of sufficient practical experience before graduating. Simulations can help with the latter, but do not provide sufficient skills to handle real situations. The author proposes post-basic midwifery internship; improved training; and broadening the functions of the midwife to include training and supervision of voluntary community workers and traditional birth attendants.

Short- and long-term effects of neonatal diazepam exposure on local cerebral glucose utilization in the rat

The short- and long-term consequences of a neonatal exposure to diazepam (DZP) on the postnatal changes in local cerebral metabolic rates for glucose (LCMRglcs) were studied by the quantitative autoradiographic [14C]2-deoxyglucose method in a total number of 66 brain structures of freely moving rats. Rat pups received a daily subcutaneous injection of 10 mg/kg DZP, of the dissolution vehicle or of saline from postnatal day 2 (P2) to 21 (P21). The animals were studied at 4 ages, P10, P14, P21 and P60. DZP induced a decrease in LCMRglcs which was restricted to 13 areas at P10, mainly sensory and limbic regions. At P14, the treatment had significant metabolic effects on 48 structures belonging to all functional systems. By P21, 23 brain areas were still affected by the treatment, mainly sensory, limbic and motor areas. At P60, i.e. at about 40 days after the end of drug exposure, LCMRglcs still decreased in 14 brain regions which were mainly sensory and limbic structures. The structures most sensitive to both short- and long-term consequences of the anticonvulsant treatment are mammillary body, limbic cortices and sensory regions. The dissolution vehicle increased LCMRglcs in a few brain regions at P14 and P60, whereas it decreased metabolic levels in 5 brain regions at P21. The results of the present study show that the brain appears to be particularly vulnerable to the treatment at P14, period of active brain growth, whereas by P21, the drug is actively metabolized and a tolerance to the treatment may occur. The long-term effects of the treatment are in good accordance with the well-known effects of DZP on anxiety, sedation and memory. The structures most sensitive to early neonatal DZP exposure are the mammillary body, limbic cortices and sensory regions that all contain a high density of benzodiazepine binding sites.

[The midwife in South Africa. Part I--The practice of the midwife]

Part 1, of a two part series on the dilemma of the midwife in South Africa, deals with the practice of the midwife. It is difficult to estimate the number of practicing midwives, as they form part of the general nursing register. Also midwifery is part of the basic nurse training and is not taught as a separate entity. The midwife in South Africa practices in the areas of primary health care, hospitals, clinics, mobile clinics, homes and MOU's. The governments commitment to PHC will likely result in most midwives practicing in this area. Problems are high maternal deaths, shortages and maldistribution of midwives in an urban/rural context and the fragmentation and poor coordination of the health services. The safe motherhood initiative of the WHO has been adopted, there are recommendations that midwifery education be separated from general nurse education, and that clinical skills be strengthened. Midwifery services in South Africa do not fulfill the basic criteria for a PHC service.

Interleukin-1 beta (IL-1 beta) binds to intact porcine thyroid follicles, decreases iodide uptake but has no effect on cAMP formation or proliferation

Interleukin-1 beta (IL-1 beta) is known to be involved in autoimmune thyroiditis. Since the results of different in vitro-studies on the effect of IL-1 on thyrocytes are controversial, our aim was to investigate the existence of specific binding sites for IL-1 beta and its influence on specific functions and growth of isolated porcine thyroid follicles ex vivo with a preserved iodide metabolism. For binding studies isolated thyroid follicles were incubated with 125I-IL-1 beta (213.5 nCi/ml) and with increasing concentrations of unlabelled IL-1 beta (0.06-11.5 nmol/l) for 24 h at 4 degrees C. The dissociation constant Kd was 0.85 x 10(-10) mol/l and about 800 binding sites per cell were calculated. IL-1 beta (10 U/ml) decreased basal and TSH-stimulated iodide uptake and organification after an incubation time of 45 min to 6 h without any influence on cAMP-formation. In addition, after 40 h of incubation IL-1 beta dose-dependently increased T3-secretion, followed by a decrease during simultaneous TSH-stimulation, whereas there was no effect on T4-secretion. In contrast to these functional effects IL-1 beta showed no influence on the growth of thyroid follicles, so that the cytokine cannot be made responsible for goiter growth in thyroid diseases by directly influencing thyroxytes.

Human neutrophil elastase increases permeability of cultured pulmonary endothelial cell monolayers

Polymorphonuclear leukocytes (PMN) contribute to increased pulmonary vascular permeability in inflammatory lung injury, but the mechanism of their action is complex. In the present study we examined possible effects of PMN-derived proteases on the permeability of pulmonary endothelial cell monolayers grown on polycarbonate filter membranes and exposed continuously to a hydrostatic pressure of 10 cm H2O. Cell- and serum free PMN-supernatants (human PMN, stimulated with 30 ng/ml phorbol-myristate acetate for 30 min, presence of catalase, were centrifuged, the supernatants were passed through a 0.45 micron filter) dose-dependently (calculated PMN: endothelial cell ratio of 2:1 and more) increased hydraulic conductivity of endothelial cell monolayers ten- to twentyfold within 20-70 min. At the same time the dextran reflection coefficient decreased from 0.8 to 0.1. Phase contrast and scanning electronmicroscopy showed a widening of intercellular gaps. The effects of the postsecretory PMN-supernatant were blocked dose-dependently by inhibitors of human neutrophil elastase (HNE) but not of cathepsin G. On quantitative grounds highly purified HNE was similarly active as postsecretory PMN supernatant. The effects of HNE were inhibited by pretreatment with eglin-c or heat, but not with heparin. The data suggest that HNE is an effective and sufficient neutrophil-derived mediator to increase endothelial permeability. HNE appears to act primarily enzymatically and not as a cationic protein.