Down-regulation of the Notch pathway mediated by a gamma-secretase inhibitor induces anti-tumour effects in mouse models of T-cell leukaemia

BACKGROUND AND PURPOSE

gamma-Secretase inhibitors (GSIs) block NOTCH receptor cleavage and pathway activation and have been under clinical evaluation for the treatment of malignancies such as T-cell acute lymphoblastic leukaemia (T-ALL). The ability of GSIs to decrease T-ALL cell viability in vitro is a slow process requiring >8 days, however, such treatment durations are not well tolerated in vivo. Here we study GSI's effect on tumour and normal cellular processes to optimize dosing regimens for anti-tumour efficacy.

EXPERIMENTAL APPROACH

Inhibition of the Notch pathway in mouse intestinal epithelium was used to evaluate the effect of GSIs and guide the design of dosing regimens for xenograft models. Serum Abeta(40) and Notch target gene modulation in tumours were used to evaluate the degree and duration of target inhibition. Pharmacokinetic and pharmacodynamic correlations with biochemical, immunohistochemical and profiling data were used to demonstrate GSI mechanism of action in xenograft tumours.

KEY RESULTS

Three days of >70% Notch pathway inhibition was sufficient to provide an anti-tumour effect and was well tolerated. GSI-induced conversion of mouse epithelial cells to a secretory lineage was time- and dose-dependent. Anti-tumour efficacy was associated with cell cycle arrest and apoptosis that was in part due to Notch-dependent regulation of mitochondrial homeostasis.

CONCLUSIONS AND IMPLICATIONS

Intermittent but potent inhibition of Notch signalling is sufficient for anti-tumour efficacy in these T-ALL models. These findings provide support for the use of GSI in Notch-dependent malignancies and that clinical benefits may be derived from transient but potent inhibition of Notch.

[Value of galvanotherapy for localised prostate cancer]

In recent years electrotherapy has become an accepted treatment option in several medical subfields such as defibrillation during cardiopulmonary resuscitation, electroconvulsive shock treatment (ECT) in conjunction with antidepressant therapy, pain management and physical therapy [transcutaneous electrical nerve stimulation (TENS), diathermia, Stanger bath therapy, etc.]. In recent years several groups, especially from Asia, have investigated the therapeutic effect of electricity in the treatment of malignant tumours. They determined basic principles of electrotherapy and developed different theories of tumour destruction. They postulated a multifactorial tissue effect of continuous current based on tumour cell necrosis due to pH shifting and alteration of membrane potential. In clinical trials similar oncological results of electrotherapy in several malignant tumours compared to established therapeutic methods were observed, whereas clinical trial designs to some extent were not consistent with internationally accepted scientific standards. Regarding electrotherapy of localised prostate cancer only limited data with a few cases and controversial study designs were published. According to EAU guidelines electrotherapy of localised prostate cancer as an alternative treatment option is not recommended and is still an experimental method. For this procedure well-designed clinical trials and a longer follow-up are mandatory to assess the true role of electrotherapy in the management of prostate cancer.

Retrospective cohort study of diagnosis-delivery interval with umbilical cord prolapse: the effect of team training

OBJECTIVE

To determine whether the introduction of multi-professional simulation training was associated with improvements in the management of cord prolapse, in particular, the diagnosis-delivery interval (DDI).

DESIGN

Retrospective cohort study.

SETTING

Large tertiary maternity unit within a University Hospital in the United Kingdom.

SAMPLE

All cases of cord prolapse with informative case record: 34 pre-training, 28 post-training.

METHODS

Review of hospital notes and software system entries; comparison of quality of management for umbilical cord prolapse pre-training (1993-99) and post-training (2001-07).

MAIN OUTCOME MEASURES

Diagnosis-delivery interval; proportion of caesarean section (CS) in whom actions were taken to reduce cord compression; type of anaesthesia for CS births; rate of low (<7) 5-minute Apgar scores; rate of admission to neonatal intensive care unit (NICU) (if birthweight >2500 g).

RESULTS

After training, there was a statistically significant reduction in median DDI from 25 to 14.5 minutes (P < 0.001). Post-training, there was also a statistically significant increase in the proportion of CS where recommended actions had been performed (from 34.78 to 82.35%, P = 0.003). There was a nonsignificant increase in the use of spinal anaesthesia for CS, from 8.70 to 17.65%, and a nonsignificant reduction in the rate of low Apgar scores from 6.45 to 0% and in the rate of admission to NICU from 38.46 to 22.22%.

CONCLUSIONS

The introduction of annual training, in accordance with national recommendations, was associated with improved management of cord prolapse. Future studies could assess whether this improved management translates into better outcomes for babies and their mothers.

The active components of effective training in obstetric emergencies

Confidential enquiries into poor perinatal outcomes have identified deficiencies in team working as a common factor and have recommended team training in the management of obstetric emergencies. Isolated aviation-based team training programmes have not been associated with improved perinatal outcomes when applied to labour ward settings, whereas obstetric-specific training interventions with integrated teamwork have been associated with clinical improvements. This commentary reviews obstetric emergency training programmes from hospitals that have demonstrated improved outcomes to determine the active components of effective training. The common features identified were: institution-level incentives to train; multi-professional training of all staff in their units; teamwork training integrated with clinical teaching and use of high fidelity simulation models. Local training also appeared to facilitate self-directed infrastructural change.

Comparative analysis of the sialic acid binding activity and the tropism for the respiratory epithelium of four different strains of avian infectious bronchitis virus

Avian infectious bronchitis virus (IBV) is a major pathogen in commercial poultry flocks. We recently demonstrated that sialic acid serves as a receptor determinant for IBV on the tracheal epithelium. Here we compared the IBV strains Beaudette, 4/91, Italy02, and QX for their sialic acid-binding properties. We demonstrate that sialic acid binding is important for the infection of primary chicken kidney cells and the tracheal epithelium by all four strains. There were only slight differences between the four strains, indicating the universal usage of sialic acids as receptor determinants by IBV. In addition, we analysed the primary target cells in the respiratory epithelium of the four different strains and found that all of them infected ciliated cells and goblet cells.

Change in knowledge of midwives and obstetricians following obstetric emergency training: a randomised controlled trial of local hospital, simulation centre and teamwork training

OBJECTIVES

To explore the effect of obstetric emergency training on knowledge. Furthermore, to assess if acquisition of knowledge is influenced by the training setting or teamwork training.

DESIGN

A prospective randomised controlled trial.

SETTING

Training was completed in six hospitals in the South West of England, UK and at the Bristol Medical Simulation Centre, UK.

POPULATION

Midwives and obstetric doctors working for the participating hospitals were eligible for inclusion in the study. A total of 140 participants (22 junior and 23 senior doctors, 47 junior and 48 senior midwives) were studied.

METHODS

Participants were randomised to one of four obstetric emergency training interventions: (1) 1-day course at local hospital, (2) 1-day course at simulation centre, (3) 2-day course with teamwork training at local hospital and (4) 2-day course with teamwork training at simulation centre.

MAIN OUTCOME MEASURES

Change in knowledge was assessed by a 185 question Multiple-Choice Questionnaire (MCQ) completed up to 3 weeks before and 3 weeks after the training intervention.

RESULTS

There was a significant increase in knowledge following training; mean MCQ score increased by 20.6 points (95% CI 18.1-23.1, P < 0.001). Overall, 123/133 (92.5%) participants increased their MCQ score. There was no significant effect on the MCQ score of either the location of training (two-way analysis of variants P = 0.785) or the inclusion of teamwork training (P = 0.965).

CONCLUSIONS

Practical, multiprofessional, obstetric emergency training increased midwives' and doctors' knowledge of obstetric emergency management. Furthermore, neither the location of training, in a simulation centre or in local hospitals, nor the inclusion of teamwork training made any significant difference to the acquisition of knowledge in obstetric emergencies.

Prevalence and functional consequence of PHOX2B mutations in neuroblastoma

PHOX2B is a homeodomain-containing protein that is involved in the development of the peripheral nervous system and is the major disease gene for the rare congenital breathing disorder congenital central hypoventilation syndrome (CCHS). Germline PHOX2B alterations were also recently discovered in neuroblastoma cases with CCHS and/or Hirschsprung disease, but a comprehensive survey for mutational frequency and functional consequence has not been performed. We therefore studied a large panel of hereditary neuroblastomas to understand the frequency and functional effects of PHOX2B mutations. Three of 47 individuals with presumed genetic predisposition to neuroblastoma showed a germline PHOX2B mutation (6.4%). Mutations were also discovered in 2 of 30 human neuroblastoma-derived cell lines, but none of 86 primary tumors from patients with sporadically occurring neuroblastoma. The vast majority of primary tumors showed abundant PHOX2B mRNA expression relative to the remainder of the transcriptome. Consistent with its role as an important neurodevelopmental gene, forced overexpression of wild-type PHOX2B in neuroblastoma cell lines suppressed cell proliferation and synergized with all-trans retinoic acid to promote differentiation. Patient-derived mutant PHOX2B constructs retained the ability to suppress cellular proliferation, but were not able to promote differentiation or activate expression of a known PHOX2B target gene in vitro. These findings show that PHOX2B alterations are a rare cause of hereditary neuroblastoma, but disruption of this neurodevelopmental pathway can interfere with transcription-dependent terminal differentiation. These data also suggest that the genetics of neuroblastoma initiation are complex, and highlight genes involved in normal noradrenergic development as candidate predisposition genes.

Variations in policies for management of the third stage of labour and the immediate management of postpartum haemorrhage in Europe

BACKGROUND

The EUropean Project on obstetric Haemorrhage Reduction: Attitudes, Trial, and Early warning System (EUPHRATES) is a set of five linked projects, the first component of which was a survey of policies for management of the third stage of labour and immediate management of postpartum haemorrhage following vaginal birth in Europe.

OBJECTIVES

The objectives were to ascertain and compare policies for management of the third stage of labour and immediate management of postpartum haemorrhage in maternity units in Europe following vaginal birth.

DESIGN

Survey of policies.

SETTING

The project was a European collaboration, with participants in 14 European countries.

SAMPLE

All maternity units in 12 countries and in selected regions of two countries in Europe.

METHODS

A postal questionnaire was sent to all or a defined sample of maternity units in each participating country.

MAIN OUTCOME MEASURES

Stated policies for management of the third stage of labour and the immediate management of postpartum haemorrhage.

RESULTS

Policies of using uterotonics for the management of the third stage were widespread, but policies about agents, timing, clamping and cutting the umbilical cord and the use of controlled cord traction differed widely. For immediate management of postpartum haemorrhage, policies of massaging the uterus were widespread. Policies of catheterising the bladder, bimanual compression and in the choice of drugs administered were much more variable.

CONCLUSIONS

Considerable variations were observed between and within countries in policies for management of the third stage of labour. Variations were observed, but to a lesser extent, in policies for the immediate management of postpartum haemorrhage after vaginal birth. In both cases, policies about the pharmacological agents to be used varied widely.

Significant increase of hantavirus infections in Germany since the beginning of 2007

Hantaviruses (family Bunyaviridae) are rodent-borne pathogens and occur worldwide. Hantavirus infections in Europe and Asia can result in a hemorrhagic fever with renal syndrome (HFRS) of different severity.

Evaluation of cyclophotocoagulation effects with 1310-nm contact optical coherence tomography

PURPOSE

The aim of this pilot study was to evaluate whether contact optical coherence tomography (OCT) allows visualization of the effects of cyclophotocoagulation.

METHODS

In this pilot study, transscleral contact OCT images (1310-nm wavelength) were generated prior to and immediately after conventional transscleral diode laser cyclophotocoagulation in three eyes of three patients who were suffering from uncontrolled glaucoma.

RESULTS

In the region of the ciliary body, transscleral contact OCT revealed two layers: (i) a superficial thick hyperreflective complex representing conjunctiva, the Tenon capsule, episclera, and sclera; and (ii) a thinner hyporeflective layer representing the ciliary body. The ciliary body could be differentiated from the overlying sclera by its marked drop in reflectivity. After cyclophotocoagulation, a marked increase of reflectivity in the treated area of the ciliary body was identifiable. After treatment, the distinct border between the hyperreflective scleral complex disappeared, and the region of the ciliary body appeared hyperreflective. The optical properties of the overlying sclera remained unchanged. On corresponding averaged A-scan images, scleral thickness appeared to be slightly increased, whereas ciliary body thickness remained unchanged.

CONCLUSIONS

This pilot study demonstrates the capability of contact OCT for allowing visualization of changes in the ciliary body after transscleral cyclophotocoagulation (TSCPC). Further investigations are planned to clarify the complete significance of these data.

Real-time imaging of transscleral diode laser cyclophotocoagulation by optical coherence tomography

PURPOSE

To present optical coherence tomography (OCT) for real-time imaging of cyclophotocoagulation effects.

METHODS

In a pilot study, real-time transscleral OCT images were generated during diode laser cyclophotocoagulation in four eyes of four patients suffering from uncontrolled glaucoma using a specially designed contact applicator containing the OCT fiber, a focussing fiber optic and the fiber of the diode laser.

RESULTS

When the contact system was used, two layers could be differentiated: a superficial thick hyperreflective complex representing conjunctiva, Tenon's capsule, episclera and sclera, and a thinner hyporeflective layer representing the ciliary body. During cyclophotocoagulation, real-time OCT showed a clear and sudden thickening of the ciliary body in the treated area.

CONCLUSION

This new OCT device represents a first step towards visual, real-time imaging of cyclophotocoagulation. After further adaptation of the delivery system, further trials are needed to correlate OCT findings with aqueous production and intraocular pressure.

The connecting tubule is the main site of the furosemide-induced urinary acidification by the vacuolar H+-ATPase

Final urinary acidification is achieved by electrogenic vacuolar H(+)-ATPases expressed in acid-secretory intercalated cells (ICs) in the connecting tubule (CNT) and the cortical (CCD) and initial medullary collecting duct (MCD), respectively. Electrogenic Na(+) reabsorption via epithelial Na(+) channels (ENaCs) in the apical membrane of the segment-specific CNT and collecting duct cells may promote H(+)-ATPases-mediated proton secretion by creating a more lumen-negative voltage. The exact localization where this supposed functional interaction takes place is unknown. We used several mouse models performing renal clearance experiments and assessed the furosemide-induced urinary acidification. Increasing Na(+) delivery to the CNT and CCD by blocking Na(+) reabsorption in the thick ascending limb with furosemide enhanced urinary acidification and net acid excretion. This effect of furosemide was abolished with amiloride or benzamil blocking ENaC action. In mice deficient for the IC-specific B1 subunit of the vacuolar H(+)-ATPase, furosemide led to only a small urinary acidification. In contrast, in mice with a kidney-specific inactivation of the alpha subunit of ENaC in the CCD and MCD, but not in the CNT, furosemide alone and in combination with hydrochlorothiazide induced normal urinary acidification. These results suggest that the B1 vacuolar H(+)-ATPase subunit is necessary for the furosemide-induced acute urinary acidification. Loss of ENaC channels in the CCD and MCD does not affect this acidification. Thus, functional expression of ENaC channels in the CNT is sufficient for furosemide-stimulated urinary acidification and identifies the CNT as a major segment in electrogenic urinary acidification.

A randomised controlled trial of a new handheld vacuum extraction device

OBJECTIVE

To evaluate the effectiveness of a new handheld vacuum delivery device.

DESIGN

Randomised controlled trial.

SETTING

Southmead Hospital, Bristol, UK.

POPULATION

One hundred and ninety-four women requiring delivery with vacuum extraction.

METHODS

Women were recruited into the study while still in early labour. If during delivery, vacuum extraction was indicated they were then randomly allocated to either a new handheld vacuum device, the Kiwi Omnicup, or to a 'standard' vacuum cup selected by the obstetrician. The 'standard group' consisted of the silastic (66/98, 67%) or the metal cups (32/98, 33%). Study data were recorded at completion of the delivery and at 24-48 hours. An additional brief symptom questionnaire was completed by the mother at 10 days postnatally. Statistical analyses were done on an 'intention-to-treat' basis.

MAIN OUTCOME MEASURES

The primary outcome was the successful completion of delivery with the allocated instrument. Secondary outcomes were substantial fetal scalp trauma and substantial maternal trauma.

RESULTS

The Omnicup was associated with a significantly higher failure rate than the standard cup [34%vs 21%, odds ratio (OR) = 1.9 (1.01-3.6)]. This difference persisted after adjusting for confounding factors [adjusted OR = 2.25 (1.01-5.0)] and resulted in significantly more forceps deliveries in the Kiwi Omnicup group [22%vs 10%, unadjusted OR = 2.5 (1.1-5.5)]. The caesarean section rates were similar in both groups [9.4%vs 8.2%, OR = 1.2 (0.4-3.2)]. Rates of substantial scalp trauma and maternal trauma were similar in both groups. However, there were more cases of jaundice in the standard cup group [2.3%vs 12.0%, unadjusted OR = 0.18 (0.04-0.82) and adjusted OR = 0.10 (0.01-0.88)].

CONCLUSIONS

The Omnicup is not as successful at achieving a vaginal delivery as the combination of the currently used vacuum cups.

Identification of Biotic and Abiotic Particles by Using a Combination of Optical Tweezers and In Situ Raman Spectroscopy

A highly versatile setup, which introduces an optical gradient trap into a Raman spectrometer, is presented. The particular configuration, which consists of two lasers, makes trapping independent from the Raman excitation laser and allows a separate adjustment of the trapping and excitation wavelengths. Thus, the excitation wavelength can be chosen according to the needs of the application. We describe the successful application of an optical gradient trap on transparent as well as on reflective, metal-coated microparticles. Raman spectra were recorded from optically trapped polystyrene beads and from single biological cells (e.g., erythrocytes, yeast cells). Also, metal-coated microparticles were trapped and used as surface enhanced Raman spectroscopy (SERS) substrates for tests on yeast cells. Furthermore, the optical gradient trap was combined with a SERS fiber probe. Raman spectra were recorded from trapped red blood cells using the SERS fiber probe for excitation.

Changes in function and morphology of normal human skin: evaluation using optical coherence tomography

BACKGROUND

Optical coherence tomography (OCT) is a noninvasive morphological method for investigating human skin. It allows high-resolution in vivo imaging of inflammatory skin diseases and tumours. Because it is a newly developed method, systematic studies on standardization and on evaluation of factors influencing the representation of the skin have not yet been performed.

OBJECTIVES

In this study, normal human skin was treated with various external stimuli which induce changes of function and morphology. Changes in stratum corneum thickness as well as changes induced by pigmentation, oedema and erythema were investigated using OCT.

METHODS

Healthy skin of human volunteers was treated with tape stripping, ultraviolet A irradiation, water, histamine, nicotinic acid and various ointments.

RESULTS

In the tape stripping experiment, the thickness of the horny layer was quantified and monitored. Pigmentation increased the light attenuation of the tissue, whereas hydration and erythema led to a slight decrease of scattering. Topical treatment of the skin gave a nonspecific increase of penetration depth of the light due to the lower reflectivity of the surface.

CONCLUSIONS

There are various physiological conditions which influence optical properties of the skin. These parameters should be considered when performing standardized OCT studies.

Impact of Insertions in the HIV-1 P6 Ptapp Region on the Virological Response to Amprenavir

We evaluated the impact of genetic changes within p6Gag gene on the virological response (VR, mean decrease in plasma viral load at week 12) to unboosted amprenavir (APV). Gag-protease fragments, including gag p2, p7, p1, p6 regions and whole protease (PR) were sequenced from baseline plasma specimens of 84 highly pre-treated but APV-naive patients included in the NARVAL (ANRS 088) trial. The correlation between baseline p6Gag polymorphism, PR mutations, baseline characteristics and VR to APV was analysed in univariate analysis. Insertions (P459Ins) within p6 protein, leading to partial or complete duplication of the PTAPP motif, were significantly associated with a decreased VR (P459Ins versus wild-type; –0.3 ±0.8 vs –1.1 ±1.2 log copies/ml, P=0.007) and were more frequent when the V82A/F/T/S PR mutation was present ( P=0.020). In multivariate analysis, after adjustment on the predictive factors of the VR in the NARVAL trial and on the PR mutations linked with response, there was a strong trend to an association ( P=0.058) between the presence of P459Ins and an altered VR. In conclusion, these results suggest that insertions in the p6 region of HIV-1 gag gene may affect the VR, in highly pre-treated patients receiving an unboosted APV-containing regimen.

Prevalence of respiratory symptoms in sheep breeders

BACKGROUND

The European Farmers' Study has indicated that sheep farmers might be at risk for the development of respiratory symptoms.

AIMS

To assess the prevalence of respiratory symptoms in sheep breeders and potential work related risk factors.

METHODS

All sheep breeders listed in two regions of South Germany were asked to answer a mailed questionnaire on respiratory symptoms, work related respiratory symptoms (WRS), and details of farming. Overall, 325 sheep breeders keeping at least 10 sheep could be included in the survey (response rate 81.9%). The prevalences were compared to the results of the European Farmers' Study.

RESULTS

Sheep breeders showed a significantly higher prevalence of asthma related symptoms (prevalence odds ratio (POR) 2.1, 95% CI 1.5 to 3.0), chronic phlegm (POR 4.0, 95% CI 2.8 to 5.9), and WRS (POR 1.7, 95% CI 1.3 to 2.2) after adjusting for age, gender, smoking habits, full time farming, and study centre. In the multiple logistic regression model the risk for asthma related symptoms was doubled in full time farmers (POR 2.3, 95% CI 1.2 to 4.3). The major predictor of WRS was full time farming (POR 1.6, 95% CI 0.93 to 2.7) and the use of chemical footbaths (POR 2.1, 95% CI 1.2 to 3.7).

CONCLUSIONS

Sheep breeders might be at high risk for the development of respiratory symptoms. These symptoms may be associated with work intensity and chemical exposure during work. Studies including objective measurements should be performed.

Potential dangers of the Valsalva maneuver and adenosine in paroxysmal supraventricular tachycardia--beware preexcitation

Paroxysmal supraventricular tachycardia (PSVT) is a common clinical problem. Valsalva maneuver and adenosine are effective therapies for many patients with PSVT, although any conversion to an irregular or wide complex tachycardia should prompt consideration of a preexcitation syndrome. We report a case where the Valsalva maneuver and adenosine, in a patient with PSVT and previously undiagnosed Wolff-Parkinson-White syndrome, caused atrial fibrillation and led to a haemodynamically unstable wide complex tachycardia and ventricular fibrillation. In PSVT, where preexcitation has not been excluded, the Valsalva maneuver and adenosine can be potentially dangerous.

The neuron-specific Ca2+-binding protein caldendrin: gene structure, splice isoforms, and expression in the rat central nervous system

Caldendrin is the founder member of a recently discovered family of calmodulin-like proteins, which are highly abundant in brain. In this study we examined the organization of the murine and human caldendrin gene as well as the expression pattern of transcripts for caldendrin and two novel splice variants. In addition the distribution of caldendrin in rat brain has been assessed by immunohistochemistry. Caldendrin is localized to the somatodendritic compartment of a subpopulation of mainly principal neurons in brain regions with a laminar organization and is present only at a subset of mature excitatory synapses. Caldendrin immunoreactivity (IR) is tightly associated with the cortical cytoskeleton, enriched in the postsynaptic density (PSD) fraction, and associates late during development with the synaptic cytomatrix. The expression is highly heterogenous within cortex, with highest levels of caldendrin IR in layer III of the piriform and layer II/III of the somatosensory cortex. The segregated cortical distribution to areas, which represent the most important primary sensory systems of the rodent brain, may reflect different requirements for dendritic Ca2+-signaling in these neurons. The presence of caldendrin in the PSD of distinct synapses may have important implications for Ca2+-modulated processes of synaptic plasticity.

[Combination of endovascular procedures with open vascular surgery]

The combination of open surgery with endoluminal catheter techniques offers new chances in the treatment of multi-staged arterial occlusive disease. We report our experiences in 205 patients. In n = 125 patients TEA or bypass were undertaken in the groin with simultaneous catheter intervention proximally or distally. In 31 patients the operation was carried out above knee and in 49 cases below knee. 94 patients with an open operation in the groin and simultaneous iliac catheter interventions are in the follow up. For these interventions the combined secondary patency rate was 77 % after three years.

Fatal form of phaeochromocytoma presenting as acute pyelonephritis

We report the case of a young man who presented with a clinical picture of acute pyelonephritis. Within 3 h of admission, the patient developed acute respiratory distress associated with tachycardia and shock, and he was transferred to the intensive care unit. Mechanical ventilation of the lungs and symptomatic treatment were started immediately. Abdominal ultrasound revealed the presence of an adrenal tumour with central necrosis indicating a probable phaeochromocytoma. There was no sign of pyelonephritis. Ventricular fibrillation followed by asystole occurred soon after admission. The suddenness of the patient's death did not allow time for further investigation and therapy. The severity of the clinical signs was probably related to a massive release of catecholamines because of necrosis of the tumour, which may have been worsened by the diagnostic procedures performed to investigate the clinical symptoms and signs of acute pyelonephritis.

Effects of dexamethasone on proliferation, chemotaxis, collagen I, and fibronectin-metabolism of human fetal lung fibroblasts

Premature infants at risk for bronchopulmonary dysplasia (BPD) are often treated with dexamethasone (Dex), which has been shown to suppress inflammatory processes in the lung. To elucidate a possible direct influence on the fibroproliferative component of the disease, we studied the effects of Dex in therapeutic and supratherapeutic dosages (5-50 nmol/L) on proliferation, chemotaxis, procollagen I, and fibronectin metabolism of human fetal lung fibroblasts in vitro. Proliferation was inhibited by Dex in a dose-dependent manner. Chemotactic activity in response to conditioned medium of human fetal fibroblasts also showed a dose-dependent inhibition after pretreatment with Dex. The amount of procollagen I C-terminal propeptide and fibronectin per cell in the cell culture supernatant was increased in the presence of Dex. Our results show that Dex does not uniformly suppress the fibroproliferative activity of human fetal lung fibroblasts, which may explain in part the unsatisfactory long-term effects of Dex treatment in BPD.

[The phantom and stump phenomena interview (PSPI)]

RESEARCH QUESTION

A structured German-language interview was developed for the assessment of painful and non-painful phantom and stump phenomena after amputation. The aim was a thorough assessment of the quality, quantity and time course of these phenomena, which is of scientific as well as therapeutic relevance.

METHODS

Each phenomenon was assessed using visual analogue scales as well as qualitative descriptors adapted from the McGill Pain Inventory and from literature reports. The factor structure and psychometric properties of the interview were evaluated in a sample of 139 upper and lower limb amputees. Test-retest coefficients were obtained in a subset of 20 amputees.

RESULTS

As expected, all pain-related scales showed a two-dimensional internal structure with the factors "affective pain" and "sensory pain". For the non-painful phantom sensations, three factors "general/kinesthetic phantom sensations", "phantom movements" and "paresthesias" were obtained, while for non-painful stump sensations only one general factor emerged. The internal consistency was high with respect to the pain-related scales and was still satisfying for the scales that cover nonpainful phantom and stump phenomena. All scales have sufficient validity. Test-retest coefficients suggest a satisfactory stability of all scales that assess present phenomena, while the stability of the retrospective scales is markedly lower and in some cases insufficient.

CONCLUSIONS

The phantom and stump phenomena interview is a highly reliable and valid instrument to assess present perceptual phenomena after amputation. Only the included retrospective scales apparently show low stability scores over time. This raises the more general question of the validity of retrospective pain reports.

The relationship of perceptual phenomena and cortical reorganization in upper extremity amputees

In this study 16 unilateral upper extremity amputees participated in a comprehensive psychophysiological examination that included the assessment of painful and non-painful phantom and stump sensations, thermal and electric perception as well as two-point discrimination thresholds, the detailed analysis of referred sensation and the measurement of reorganizational changes in primary somatosensory cortex using neuroelectric source imaging. Reorganization of the primary somatosensory cortex was associated with increased habitual phantom limb pain, telescoping, non-painful stump sensations and painful referred sensation induced by painful stimulation. It was unrelated to non-painful phantom sensations, non-painful referred sensation elicited by painful or non-painful stimulation, painful referred sensation elicited by non-painful stimulation, perception thresholds and stump pain. These data substantiate the hypothesis that painful and non-painful phantom phenomena are mediated by different neural substrates.

Perceptual phenomena after unilateral arm amputation: a pre-post-surgical comparison

Painful and non-painful phantom phenomena occur frequently after amputations but are rarely investigated in the perioperative stage. The goal of the present study was the assessment of phantom phenomena, pain and changes in primary somatosensory cortex prior to and after upper limb amputation. Two patients who suffered from metastatic carcinoma were examined 2 days prior to and 7 days after the amputation of an arm using comprehensive psychometric assessments and neuroelectric source imaging. Both patients reported phantom limb pain that was similar to their pre-amputation pain. In one patient, reorganization of the mouth area into the deafferented hand area took place immediately after the amputation. In the other patient reorganization had occurred prior to the amputation possibly related to non-use of the arm several years prior to the amputation.

The circadian clock of fruit flies is blind after elimination of all known photoreceptors

Circadian rhythms are entrained by light to follow the daily solar cycle. We show that Drosophila uses at least three light input pathways for this entrainment: (1) cryptochrome, acting in the pacemaker cells themselves, (2) the compound eyes, and (3) extraocular photoreception, possibly involving an internal structure known as the Hofbauer-Buchner eyelet, which is located underneath the compound eye and projects to the pacemaker center in the brain. Although influencing the circadian system in different ways, each input pathway appears capable of entraining circadian rhythms at the molecular and behavioral level. This entrainment is completely abolished in glass(60j) cry(b) double mutants, which lack all known external and internal eye structures in addition to being devoid of cryptochrome.

Terminal-restriction fragment length polymorphism (T-RFLP) screening of a marine archaeal clone library to determine the different phylotypes

T-RFLP clone characterization (screening) was optimized for a fast and basepair-accurate characterization of clones from marine Archaea collected from the Eastern Mediterranean Sea. Because of the high sensitivity of T-RFLP fingerprinting, a protocol was developed where 10 initial PCR cycles gave detectable terminal fragments from clones. Additionally, forward and reverse primers for PCR were individually labeled and detected simultaneously to assess the suitability of the forward and reverse fragments for T-RFLP screening. Based on independent restriction digests with the tetrameric restriction enzymes HhaI, RsaI and HaeIII to characterize the 49 archaeal clones in our library, the clones were grouped into 13 T-RFLP operational taxonomic units (OTUs). Reverse fragments generally gave less heterogeneous fragments in size. The accuracy of T-RFLP screening was evaluated by sequencing representative clones. Closely related clones ( approximately 97% similarity) could only be resolved with multiple restriction digests where forward and reverse fragments were included in the analysis. All fragments from the clone library were detected in the T-RFLP fingerprint from the complex archaeal community. We found representatives of marine group I, II and III Archaea. Thus, the recently discovered low abundant marine group III Archaea could be clearly differentiated from the other clones in our library and comprised a considerable fraction of the clone library ( approximately 12%). Therefore, our T-RFLP screening approach proved successful in characterizing novel archaeal sequences from the marine environment.