Proteomic profiling of TGFBI-null mouse corneas reveals only minor changes in matrix composition supportive of TGFBI knockdown as therapy against TGFBI-linked corneal dystrophies

TGFBIp is a constituent of the extracellular matrix in many human tissues including the cornea, where it is one of the most abundant proteins expressed. TGFBIp interacts with Type I, II, IV, VI, and XII collagens as well as several members of the integrin family, suggesting it plays an important role in maintaining structural integrity and possibly corneal transparency as well. Significantly, more than 60 point mutations within the TGFBI gene have been reported to result in aberrant TGFBIp folding and aggregation in the cornea, resulting in severe visual impairment and blindness. Several studies have focused on targeting TGFBIp in the cornea as a therapeutic approach to treat TGFBI-linked corneal dystrophies, but the effect of this approach on corneal homeostasis and matrix integrity remained unknown. In the current study, we evaluated the histological and proteomic profiles of corneas from TGFBI-deficient mice as well as potential redundant functions of the paralogous protein POSTN. The absence of TGFBIp in mouse corneas did not grossly affect the collagen scaffold, and POSTN is unable to compensate for loss of TGFBIp. Proteomic comparison of wild-type and TGFBI^-/- mice revealed 11 proteins were differentially regulated, including Type VI and XII collagens. However, as these alterations did not manifest at the macroscopic and behavioral levels, these data support partial or complete TGFBI knockdown as a potential therapy against TGFBI-linked corneal dystrophies. Lastly, in situ hybridization verified TGFBI mRNA in the epithelial cells but not in other cell types, supportive of a therapy directed specifically at this lineage.

First Measurement of Electron Neutrino Appearance in NOvA

We report results from the first search for ν_{μ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.99±0.11(syst) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of 1.07±0.14(syst). The 3.3σ excess of events observed in the primary analysis disfavors 0.1π<δ_{CP}<0.5π in the inverted mass hierarchy at the 90% C.L.

The phagocytic fitness of leucopatches may impact the healing of chronic wounds

Chronic non-healing wounds are significantly bothersome to patients and can result in severe complications. In addition, they are increasing in numbers, and a challenging problem to the health-care system. Handling of chronic, non-healing wounds can be discouraging due to lack of improvement, and a recent explanation can be the involvement of biofilm infections in the pathogenesis of non-healing wounds. Therefore, new treatment alternatives to improve outcome are continuously sought-after. Autologous leucopatches are such a new, adjunctive treatment option, showing promising clinical effects. However, the beneficial effect of the patches are not understood fully, although a major contribution is believed to be from the release of stimulating growth factors from activated thrombocytes within the leucopatch. Because the leucopatches also contain substantial numbers of leucocytes, the aim of the present study was to investigate the activity of the polymorphonuclear neutrophils (PMNs) within the leucopatch. By means of burst assay, phagocytosis assay, migration assay, biofilm killing assay and fluorescence in-situ hybridization (FISH) assay we showed significant respiratory burst in PMNs, active phagocytosis and killing of Pseudomonas aeruginosa by the leucopatch. In addition, bacterial-induced migration of PMNs from the leucopatch was shown, as well as uptake of P. aeruginosa by PMNs within the leucopatch. The present study substantiated that at least part of the beneficial clinical effect in chronic wounds by leucopatches is attributed to the activity of the PMNs in the leucopatch.

The Ultrastructures and Mechanical Properties of the Descement's Membrane in Fuchs Endothelial Corneal Dystrophy

Fuchs endothelial corneal dystrophy (FECD), is the most common corneal endothelial dystrophy, and contributes up to 50% of all corneal transplantations performed in developed countries. FECD develops in Descemet’s membrane (DM) and possibly alters the mechanical properties and internal structures in this basal lamina. In this work, the morphology and mechanical properties of FECD-DMs are studied by transmission electron microscopy (TEM) and quantitative dynamic atomic force microscopy (QD-AFM) at nano scale. Pathological wide-space collagens that are typical of FECD display different mechanical properties in that they are softer than the remaining tissue both for dehydrated- and fully hydrated samples. Additionally, the hydration level has major influence on the mechanical properties. These findings could help to further understand the structural changes in FECD, and possibly be useful for further characterization of the disease, the diagnosis and assessment or even pathologic analysis.

Low efficacy of tobramycin in experimental Staphylococcus aureus endocarditis

The empiric treatment of infective endocarditis (IE) varies widely and, in some places, a regimen of penicillin in combination with an aminoglycoside is administered. The increasing incidence of Staphylococcus aureus IE, poor tissue penetration by aminoglycosides and low frequency of penicillin-susceptible S. aureus may potentially lead to functional tobramycin monotherapy. Therefore, this study aimed to evaluate tobramycin monotherapy in an experimental S. aureus IE rat model. Catheter-induced IE at the aortic valves were established with S. aureus (NCTC 8325-4) and rats were randomised into untreated (n = 22) or tobramycin-treated (n = 13) groups. The treatment group received tobramycin once-daily. Animals were evaluated at 1 day post infection (DPI), 2 DPI or 3 DPI. Quantitative bacteriology and cytokine expression were measured for valves, myocardium and serum. A decrease of bacterial load was observed in valves and the spleens of the treated (n = 6) compared to the untreated group at 2 DPI (n = 8) (p ≤ 0.02 and p ≤ 0.01, respectively), but not at 3 DPI (n = 7). Quantitative bacteriology in the myocardium was not different between the groups. Keratinocyte-derived chemokine (KC) in the aortic valves was significantly reduced at 2 DPI in the tobramycin-treated group (p ≤ 0.03). However, the expression of interleukin (IL)-1b, IL-6 and granulocyte-colony stimulating factor (G-CSF) in the valves was not different between the two groups. In the myocardium, a significant reduction in IL-1b was observed at 2 DPI (p ≤ 0.001) but not at 3 DPI. Tobramycin as functional monotherapy only reduced bacterial load and inflammation transiently, and was insufficient in most cases of S. aureus IE.

Anti-Pseudomonas aeruginosa IgY Antibodies Induce Specific Bacterial Aggregation and Internalization in Human Polymorphonuclear Neutrophils

Polymorphonuclear neutrophils (PMNs) are essential cellular constituents in the innate host response, and their recruitment to the lungs and subsequent ubiquitous phagocytosis controls primary respiratory infection. Cystic fibrosis pulmonary disease is characterized by progressive pulmonary decline governed by a persistent, exaggerated inflammatory response dominated by PMNs. The principal contributor is chronic Pseudomonas aeruginosa biofilm infection, which attracts and activates PMNs and thereby is responsible for the continuing inflammation. Strategies to prevent initial airway colonization with P. aeruginosa by augmenting the phagocytic competence of PMNs may postpone the deteriorating chronic biofilm infection. Anti-P. aeruginosa IgY antibodies significantly increase the PMN-mediated respiratory burst and subsequent bacterial killing of P. aeruginosa in vitro. The mode of action is attributed to IgY-facilitated formation of immobilized bacteria in aggregates, as visualized by fluorescence microscopy and the induction of increased bacterial hydrophobicity. Thus, the present study demonstrates that avian egg yolk immunoglobulins (IgY) targeting P. aeruginosa modify bacterial fitness, which enhances bacterial killing by PMN-mediated phagocytosis and thereby may facilitate a rapid bacterial clearance in airways of people with cystic fibrosis.

Is calcaneal quantitative ultrasound useful as a prescreen stratification tool for osteoporosis?

Calcaneal quantitative ultrasound (QUS) is attractive as a prescreening tool for osteoporosis, alternative to dual-energy X-ray absorptiometry. We investigated the literature of the usability of calcaneal QUS. We found large heterogeneity between studies and uncertainty about cutoff, device, and measured variable. Despite osteoporosis-related fractures being a major health issue, osteoporosis remains underdiagnosed. Dual-energy X-ray absorptiometry (DXA) of the hip or spine is currently the preferred method for diagnosis of osteoporosis, but the method is limited by low accessibility. QUS is a method for assessing bone alternative to DXA. The aim of this systematic review was to explore the usability of QUS as a prescreen stratification tool for assessment of osteoporosis. Studies that evaluated calcaneal QUS with DXA of the hip or spine as the gold standard was included. We extracted data from included studies to calculate number of DXAs saved and misclassification rates at cutoffs equal to high sensitivity and/or specificity. The number of DXAs saved and percentage of persons misclassified were measures of usability. We included 31 studies. Studies were heterogeneous regarding study characteristics. Analyses showed a wide spectrum of percentage of DXAs saved (2.7-68.8%) and misclassification rates (0-12.4%) depending on prescreen strategy and study characteristics, device, measured variable, and cutoff. Calcaneal QUS is potentially useful as a prescreen tool for assessment of osteoporosis. However, there is no consensus of device, variable, and cutoff. Overall, there is no sufficient evidence to recommend a specific cutoff for calcaneal QUS that provides a certainty level high enough to rule in or out osteoporosis. Calcaneal QUS in a prescreen or stratification algorithm must be based on device-specific cutoffs that are validated in the populations for which they are intended to be used.

High stability and cooperative unfolding of α-synuclein oligomers

Many neurodegenerative diseases are linked with formation of amyloid aggregates. It is increasingly accepted that not the fibrils but rather oligomeric species are responsible for degeneration of neuronal cells. Strong evidence suggests that in Parkinson's disease (PD), cytotoxic α-synuclein (αSN) oligomers are key to pathogenicity. Nevertheless, insight into the oligomers' molecular properties remains scarce. Here we show that αSN oligomers, despite a large amount of disordered structure, are remarkably stable against extreme pH, temperature, and even molar amounts of chemical denaturants, though they undergo cooperative unfolding at higher denaturant concentrations. Mutants found in familial PD lead to slightly larger oligomers whose stabilities are very similar to that of wild-type αSN. Isolated oligomers do not revert to monomers but predominantly form larger aggregates consisting of stacked oligomers, suggesting that they are off-pathway relative to the process of fibril formation. We also demonstrate that 4-(dicyanovinyl)julolidine (DCVJ) can be used as a specific probe for detection of αSN oligomers. The high stability of the αSN oligomer indicates that therapeutic strategies should aim to prevent the formation of or passivate rather than dissociate this cytotoxic species.

Hydrated human corneal stroma revealed by quantitative dynamic atomic force microscopy at nanoscale

The structures and mechanical properties of human tissues are significantly influenced by water. The functionality of the human cornea can be linked to the hydrated collagen fibers. By applying quantitative dynamic atomic force microscopy to investigate morphological and mechanical property variations of corneal stroma under different hydration levels, we found that the collagen fibers in the stromal tissue show the specific periodicities and the stiffness of giga-Pa magnitude at 40% humidity. However, under increasing hydration, the collagen fibers clearly show nanoparticle structures along the fibers with the stiffness in mega-Pa magnitude. By increasing the hydration time, the stroma regains the fiber structure but with larger diameter. The age-dependency in stiffness was further investigated. The interplay of structures and nanomechanical mapping may be applied for the future diagnosis and assessment or even pathologic analysis.

A comparison between the chemical behaviour of lead-gold and lead-bismuth eutectics towards 316L stainless steel

Lead-gold eutectic (LGE) has been recently proposed as an alternative target material for high power spallation sources. In order to compare the corrosive properties of LGE to the better-studied eutectic of lead-bismuth (LBE), an isothermal twin-loop made of SS 316L was built and operated at the Institute of Physics of the University of Latvia. We have measured the concentration of steel alloying elements dissolved in both alloys at the end of two test campaigns via ICP-OES. In case of LGE, a pronounced concentration increase of Fe, Ni, Mn and Cr is found in the liquid metal, which is significantly higher compared to LBE. Similar results were obtained during complementary investigations on material samples exposed to both alloys in this twin-loop at 400 ◦C and 450 ◦C. These findings indicate that in contact with LGE, SS 316L steel suffers from substantial chemical attack. Detailed investigations using structure materials other than SS 316L have to be undertaken before qualifying LGE as a serious alternative to LBE.

Targeting of peptide conjugated magnetic nanoparticles to urokinase plasminogen activator receptor (uPAR) expressing cells

Ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles are currently being used as a magnetic resonance imaging (MRI) contrast agent in vivo, mainly by their passive accumulation in tissues of interest. However, a higher specificity can ideally be achieved when the nanoparticles are targeted towards cell specific receptors and this may also facilitate specific drug delivery by an enhanced target-mediated endocytosis. We report efficient peptide-mediated targeting of magnetic nanoparticles to cells expressing the urokinase plasminogen activator receptor (uPAR), a surface biomarker for poor patient prognosis shared by several cancers including breast, colorectal, and gastric cancers. Conjugation of a uPAR specific targeting peptide onto polyethylene glycol (PEG) coated USPIO nanoparticles by click chemistry resulted in a five times higher uptake in vitro in a uPAR positive cell line compared to nanoparticles carrying a non-binding control peptide. In accordance with specific receptor-mediated recognition, a low uptake was observed in the presence of an excess of ATF, a natural ligand for uPAR. The uPAR specific magnetic nanoparticles can potentially provide a useful supplement for tumor patient management when combined with MRI and drug delivery.

Bead-size directed distribution of Pseudomonas aeruginosa results in distinct inflammatory response in a mouse model of chronic lung infection

Chronic Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients is characterized by biofilms, tolerant to antibiotics and host responses. Instead, immune responses contribute to the tissue damage. However, this may depend on localization of infection in the upper conductive or in the peripheral respiratory zone. To study this we produced two distinct sizes of small alginate beads (SB) and large beads (LB) containing P. aeruginosa. In total, 175 BALB/c mice were infected with either SB or LB. At day 1 the quantitative bacteriology was higher in the SB group compared to the LB group (P < 0·003). For all time-points smaller biofilms were identified by Alcian blue staining in the SB group (P < 0·003). Similarly, the area of the airways in which biofilms were identified were smaller (P < 0·0001). A shift from exclusively endobronchial to both parenchymal and endobronchial localization of inflammation from day 1 to days 2/3 (P < 0·05), as well as a faster resolution of inflammation at days 5/6, was observed in the SB group (P < 0·03). Finally, both the polymorphonuclear neutrophil leucocyte (PMN) mobilizer granulocyte colony-stimulating factor (G-CSF) and chemoattractant macrophage inflammatory protein-2 (MIP-2) were increased at day 1 in the SB group (P < 0·0001). In conclusion, we have established a model enabling studies of host responses in different pulmonary zones. An effective recognition of and a more pronounced host response to infection in the peripheral zones, indicating that increased lung damage was demonstrated. Therefore, treatment of the chronic P. aeruginosa lung infection should be directed primarily at the peripheral lung zone by combined intravenous and inhalation antibiotic treatment.

Activity of the kinesin spindle protein inhibitor ispinesib (SB-715992) in models of breast cancer

PURPOSE

Ispinesib (SB-715992) is a potent inhibitor of kinesin spindle protein, a kinesin motor protein essential for the formation of a bipolar mitotic spindle and cell cycle progression through mitosis. Clinical studies of ispinesib have shown a 9% response rate in patients with locally advanced or metastatic breast cancer and a favorable safety profile without significant neurotoxicities, gastrointestinal toxicities, or hair loss. To better understand the potential of ispinesib in the treatment of breast cancer, we explored the activity of ispinesib alone and in combination with several therapies approved for the treatment of breast cancer.

EXPERIMENTAL DESIGN

We measured the ispinesib sensitivity and pharmacodynamic response of breast cancer cell lines representative of various subtypes in vitro and as xenografts in vivo and tested the ability of ispinesib to enhance the antitumor activity of approved therapies.

RESULTS

In vitro, ispinesib displayed broad antiproliferative activity against a panel of 53 breast cell lines. In vivo, ispinesib produced regressions in each of five breast cancer models and tumor-free survivors in three of these models. The effects of ispinesib treatment on pharmacodynamic markers of mitosis and apoptosis were examined in vitro and in vivo, revealing a greater increase in both mitotic and apoptotic markers in the MDA-MB-468 model than in the less sensitive BT-474 model. In vivo, ispinesib enhanced the antitumor activity of trastuzumab, lapatinib, doxorubicin, and capecitabine and exhibited activity comparable with paclitaxel and ixabepilone.

CONCLUSIONS

These findings support further clinical exploration of kinesin spindle protein inhibitors for the treatment of breast cancer.

Bone metabolism and bone status in osteoporotic patients

We have studied bone turnover and bone status in 29 patients with hip fractures and compared them with normal subjects and patients with arthritis of the hip. Markers for bone formation, bone Gla protein, alkaline phosphatase and whole body retention of 99mTc-diphosphonate, and fasting urinary hydroxyproline, a marker for bone resorption, were all significantly higher in the hip fracture group than in the control group. The serum concentrations of 1,25-dihydroxyvitamin D were similar in the three groups, whereas the serum 25-hydroxyvitamin D concentration in the control group was higher than in the patient groups. The bone mineral content (BMC) measured in the distal forearm and the spine was lower than normal in the hip fracture group. We conclude that patients with hip fractures have an increased bone turnover with no signs of bimodality and low BMC values at all locations.

Dietary calcium intake and blood pressure in normotensive subjects

Epidemiological and prospective studies in man and animals have indicated an inverse relationship between calcium intake and cardiovascular mortality and blood pressure (BP). We have therefore studied the effect of dietary calcium on blood pressure in two groups of women. In a cross-sectional study 103 early postmenopausal women were stratified into three groups according to daily calcium intake calculated from a questionnaire. Both diastolic and systolic blood pressures were identical in the three groups. We thereafter conducted a prospective placebo-controlled trial on the effect of calcium supplementation. Twenty-eight healthy women were randomized to placebo treatment (n = 14) or calcium supplementation 2,000 mg daily (n = 14) for one year. In both groups BP remained at initial levels throughout the study and was identical in the two groups at measurements every three months. We thus conclude that calcium supplementation has no effect on BP in normotensive subjects on a high calcium diet.

Ispinesib (SB-715992) a kinesin spindle protein (KSP) inhibitor has single agent activity and enhances the efficacy of standard-of-care therapies in pre-clinical models of breast cancer

Abstract #2122

Background: Ispinesib is a novel highly specific small molecule inhibitor of kinesin spindle protein (KSP), a motor protein that is essential for formation of a bipolar mitotic spindle and for cell cycle progression through mitosis. KSP is expressed only in proliferating cells and not in post-mitotic neurons. In preclinical models and clinical studies thus far, ispinesib exhibits a favorable safety profile compared with tubulin-targeted therapies. Ispinesib has demonstrated clinical activity in patients with locally advanced or metastatic breast cancer that failed to respond/relapsed after treatment with taxanes and anthracyclines, and is currently being evaluated in a Phase I/II trial as first-line treatment in chemotherapy-naïve patients with locally advanced (Stage IIIB) or metastatic (Stage IV) breast cancer. In the current study, we explored the anti-tumor activity of ispinesib as a single agent and in combination with approved therapies in preclinical models of breast cancer. Methods: We implanted cells representative of hormone receptor positive luminal tumors (MCF-7), tumors overexpressing Her-2 (KPL4, HCC1954, BT474) or triple-negative basal tumors (MDA-MB-468) in immunodeficient female Nude or SCID mice. We started dosing Ispinesib when tumor volume reached 100-150mm3 and monitored xenograft growth for 60 days post treatment. Results: Ispinesib administered i.p. as a single agent on a q4dx3 schedule at its MTD induced tumor regressions in all five models of human breast cancer. In particular, all treated MDA-MB-468 xenografts (7/7) were tumor free survivors at 90 days post dosing. In tumors collected at different times post-dosing, we observed a strong mitotic arrest, inhibition of proliferation, and increased apoptosis by western blotting and IHC analyses of PH3, Ki67 and cleaved PARP respectively. We also determined the efficacy of ispinesib in combination with standard-of-care therapies in breast cancer. In the Her2 overexpressing models, the combination of ispinesib and herceptin markedly improved response rate and efficacy over either single agent. Tumor Growth Inhibition (TGI) was 99% for the combined agents, 67% for herceptin and 78% for ispinesib in KPL4. A similar benefit was found by combining ispinesib with lapatinib in BT474. Finally, ispinesib enhanced the anti-tumor activity of doxorubicin, causing an increase in TGI in 2 separate models (in MCF7, TGI was 86% for the combined agents, 39% for doxorubicin and 67% for ispinesib). Additional combination studies with capecitabine are under investigation.Conclusions: In distinct models of human breast cancer, ispinesib exhibited significant anti-tumor activity as a single agent. When used in combination, ispinesib enhanced the activity of standard-of-care therapies herceptin, lapatinib and doxorubicin. These data suggest that ispinesib may offer clinical benefit in the treatment of breast cancer, and support clinical studies of ispinesib in combination with these therapies.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2122.

No evidence for presence of bacteria in modic type I changes

BACKGROUND

Recent studies suggest an association between sciatica and Propionibacterium acnes. "Modic type I changes" in the vertebrae are closely associated with sciatica and lower back pain, and recent studies have questioned the ability of conventional magnetic resonance imaging (MRI) to differentiate between degenerative Modic type I changes and vertebral abnormalities caused by infection.

PURPOSE

To test whether bacteria could be cultured from biopsies of Modic type I changes.

MATERIAL AND METHODS

Twenty-four consecutive patients with Modic type I changes in lumbar vertebrae had a biopsy taken from the affected vertebra by a strict aseptic procedure. The biopsy was split into two specimens, which were inoculated into thioglycolate agar tubes in the surgical theatre and transported to the microbiology laboratory. In the laboratory, one specimen was streaked onto plates and analyzed for anaerobic and aerobic culture. The other tube was left unopened and incubated directly. Plates and tubes were incubated for 2 weeks and observed for visible growth.

RESULTS

None of the biopsies yielded growth of anaerobic bacteria. In one patient, both biopsies yielded growth of Staphylococcus epidermidis, and in another patient coagulase-negative staphylococci were isolated from one biopsy. Both patients received oral antibiotics without convincing effect on symptoms.

CONCLUSION

Our results showed no evidence of bacteria in vertebrae with Modic type I changes. The isolation of staphylococci from two patients probably represented contamination.

Clinical and radiographic spectrum of pathologically confirmed tumefactive multiple sclerosis

Atypical imaging features of multiple sclerosis lesions include size >2 cm, mass effect, oedema and/or ring enhancement. This constellation is often referred to as ‘tumefactive multiple sclerosis’. Previous series emphasize their unifocal and clinically isolated nature, however, evolution of these lesions is not well defined. Biopsy may be required for diagnosis. We describe clinical and radiographic features in 168 patients with biopsy confirmed CNS inflammatory demyelinating disease (IDD). Lesions were analysed on pre- and post-biopsy magnetic resonance imaging (MRI) for location, size, mass effect/oedema, enhancement, multifocality and fulfilment of Barkhof criteria. Clinical data were correlated to MRI. Female to male ratio was 1.2 : 1, median age at onset, 37 years, duration between symptom onset and biopsy, 7.1 weeks and total disease duration, 3.9 years. Clinical course prior to biopsy was a first neurological event in 61%, relapsing–remitting in 29% and progressive in 4%. Presentations were typically polysymptomatic, with motor, cognitive and sensory symptoms predominating. Aphasia, agnosia, seizures and visual field defects were observed. At follow-up, 70% developed definite multiple sclerosis, and 14% had an isolated demyelinating syndrome. Median time to second attack was 4.8 years, and median EDSS at follow-up was 3.0. Multiple lesions were present in 70% on pre-biopsy MRI, and in 83% by last MRI, with Barkhof criteria fulfilled in 46% prior to biopsy and 55% by follow-up. Only 17% of cases remained unifocal. Median largest lesion size on T2-weighted images was 4 cm (range 0.5–12), with a discernible size of 2.1 cm (range 0.5–7.5). Biopsied lesions demonstrated mass effect in 45% and oedema in 77%. A strong association was found between lesion size, and presence of mass effect and/or oedema (P< 0.001). Ring enhancement was frequent. Most tumefactive features did not correlate with gender, course or diagnosis. Although lesion size >5 cm was associated with a slightly higher EDSS at last follow-up, long-term prognosis in patients with disease duration >10 years was better (EDSS 1.5) compared with a population-based multiple sclerosis cohort matched for disease duration (EDSS 3.5; P< 0.001). Given the retrospective nature of the study, the precise reason for biopsy could not always be determined. This study underscores the diagnostically challenging nature of CNS IDDs that present with atypical clinical or radiographic features. Most have multifocal disease at onset, and develop RRMS by follow-up. Although increased awareness of this broad spectrum may obviate need for biopsy in many circumstances, an important role for diagnostic brain biopsy may be required in some cases.

5jährige Erfahrungen mit adjuvanter Chemotherapie beim primären Mammakarzinom

In 515 patients with primary carcinoma of the breast T1a-3aN1a-bM0, the authors conducted simple mastectomy with radical lymphonodectomy of the axilla from 1976 onwards to the time of reporting. In 190 patients with affected lymph nodes, assisting chemotherapy was effected with a combination of three drugs, namely, trofosfamide, methotrexate and 5-fluoro-uracil for a period of 12 months postoperatively. Patients whose lymph nodes remained free were not subjected to follow-up treatment. For both groups of patients, the rates of relapses and survival times were established for an average follow-up time of 41 months (15-75). No significant differences in the rates of relapses and localisation were seen on comparing both groups (P = 0.27). In the patients with affected lymph nodes, local relapses were somewhat more frequent than with patients whose lymph nodes were not affected (11.1% vs. 9.8%); the same also applied to the occurrence of metastases distant from the primary tumour (12.1% vs. 7.4%). Significant differences in survival rates in patients with affected lymph nodes were seen only in the tumour stages T1/T2 (P = 0.001) and for the stages T2/T3 (P = 0.009). The menopausal status of the patients did not show any significant differences in respect of probability of survival for both groups (N-:P = 0.75; N+:P = 0.79).

Association of renal Na,K-ATPase alpha-subunit with the beta- and gamma-subunits based on cryoelectron microscopy

Na,K-ATPase transports Na(+) and K(+) across cell membranes and consists of alpha- and beta-subunits. Na,K-ATPase also associates with small FXYD proteins that regulate the activity of the pump. We have used cryoelectron microscopy of two-dimensional crystals including data to 8 A resolution to determine the three-dimensional (3-D) structure of renal Na,K-ATPase containing FXYD2, the gamma-subunit. A homology model for the alpha-subunit was calculated from a Ca(2+)-ATPase structure and used to locate the additional beta- and gamma-subunits present in the 3-D map of Na,K-ATPase. Based on the 3-D map, the beta-subunit is located close to transmembrane helices M8 and M10 and the gamma-subunit is adjacent to helices M2 and M9 of the alpha-subunit.

Club foot

The aetiology of congenital club foot is unclear. Although studies on populations, families and twins suggest a genetic component, the mode of inheritance does not comply with distinctive patterns.

The Odense-based Danish Twin Registry contains data on all 73 000 twin pairs born in Denmark over the last 130 years. In 2002 all 46 418 twins born between 1931 and 1982 received a 17-page questionnaire, one question of which was ‘Were you born with club foot?’ A total of 94 twins answered ‘Yes’, giving an overall self-reported prevalence of congenital club foot of 0.0027 (95% confidence interval (CI) 0.0022 to 0.0034). We identified 55 complete twin pairs, representing 12 monozygotic, 22 dizygotic same sex (DZss), 18 dizygotic other sex (DZos) and three unclassified. Two monozygotic and 2 DZss pairs were concordant. The pairwise concordance was 0.17 (95% CI 0.02 to 0.48) for monozygotic, 0.09 (95% CI 0.01 to 0.32) for DZss and 0.05 (95% CI 0.006 to 0.18) for all dizygotic (DZtot) twins.

We have found evidence of a genetic component in congenital club foot, although non-genetic factors must play a predominant role.

Methodological aspects of high-frequency ultrasound of skin in children

BACKGROUND

High-frequency ultrasound of the skin has recently been introduced for assessment of systemic effects in the cutis and subcutis of oral and inhaled glucocorticoids in children. However, the use of high-frequency skin ultrasound in clinical trials is invalidated because important methodological aspects have not been addressed. The aim of the present study was to evaluate inter- and intraobserver, day to day and diurnal variations of measurement of thickness of cutis and subcutis, and the fraction of low echogenic pixels (fLEP) in the cutis and, furthermore, to assess effects of exercise on the cutis and subcutis and variations in subcutaneous thickness between anatomical locations in children with a high-frequency B-mode ultrasound scanning device.

METHODS

Three studies were conducted, each including 10 healthy prepubertal children. High-frequency skin ultrasound was performed with the 20 MHz Dermascan C (Cortex Technology, Hadsund, Denmark). In study 1, the same observer performed five consecutive scannings to assess intraobserver variations. In study two different observers performed scannings at 2 h intervals between 08:00 and 20:00 h, whereby interobserver and diurnal variations were assessed. In study 3, the same observer performed scannings in different anatomical locations on five consecutive days, and on one of these days before and after exercise. Thus day-to-day variations and the effect of exercise were assessed.

RESULTS

Low inter- and intraobserver variations were found on assessment of the thickness of cutis and subcutis, whereas high variations were found on evaluation of the dermal water content. Diurnal variations were absent, and day-to-day variations were low. Exercise caused significant increases in the thickness of cutis and subcutis on the thigh.

CONCLUSION

Low inter- and intraobserver variations make high-frequency ultrasound a precise and reliable tool for assessment of the cutaneous and subcutaneous thickness in children. In future trials, repetitive scannings need not to be performed at the same time of the day, whereas strenuous physical activity should be avoided on days of examination.

Lower leg growth suppression caused by inhaled glucocorticoids is not accompanied by reduced thickness of the cutis or subcutis

BACKGROUND

Exogenous glucocorticoids suppress short-term lower leg growth in children as assessed by knemometry. The knemometric measurements, however, may be confounded by reductions in the thickness of the cutis and subcutis over the knee.

AIM

To assess whether inhaled glucocorticoid-induced suppression of short-term growth is accompanied by changes in the thickness of the cutis and subcutis.

METHODS

The study was a randomized, controlled, crossover trial with 1 wk treatment, run-in and washout periods. Active treatment was inhaled budesonide 200 microg twice daily. Short-term growth was assessed by knemometry, and the thickness of the cutis and subcutis over the knee, on the volar forearm and abdomen was measured by 20 MHz B-mode ultrasound.

MATERIAL

Nineteen children with asthma aged 7 to 13 y.

RESULTS

Lower leg growth was significantly reduced during budesonide treatment (0.27 mm/wk) compared to the treatment-free period (0.54 mm/wk) (p = 0.02, 95%: -0.50 to -0.05). Variations in the thickness of the cutis were seen during budesonide treatment (mean +/- SEM): -0.01 +/- 0.03 mm over the knee, -0.02 +/- 0.02 mm on the forearm and 0.01 +/- 0.02 mm on the abdomen. The variations in the total thickness of the cutis and subcutis were -0.05 +/- 0.12 mm, 0.06 +/- 0.12 mm and -0.06 +/- 0.10 mm during budesonide treatment. The variations in thickness of the cutis or subcutis were not statistically different during budesonide treatment and the treatment free period in any anatomical location.

CONCLUSIONS

Short-term lower leg growth suppression induced by inhaled glucocorticoids is not confounded by variations in thickness of cutis or subcutis. The present observations further establishes knemometry as a reliable tool for assessment of the risk of growth suppression of inhaled glucocorticoids in children with asthma.

Local sensory ganglion ischemia induced by endothelin vasoconstriction: vulnerability of diabetic neurons and microvessels

In some disorders of the peripheral nervous system, it is relevant to understand how sensory neurons respond to selective ganglion ischemia. Sensory dorsal root ganglia may be susceptible to ischemic damage and irretrievable neuron loss because of their metabolic requirements. In diabetes, heightened sensitivity to ischemia associated with elevated endothelin levels might render ganglia particularly vulnerable. In this work, we created a model of local sensory ganglion ischemia by generating intense local vasoconstriction from applied endothelin-1 (ET). In this model, we compared relative vulnerability of L5 ganglia microvessels and neurons to ET in streptozotocin-induced diabetic rats and nondiabetic controls. Diabetic ganglia had reductions in baseline core ganglion blood flow (GBF) measured using microelectrode hydrogen clearance polarography and ET induced particularly profound declines. Serial GBF measurements made using a laser Doppler flowmetry probe also indicated that diabetic ganglia exposed to ET had a marked prolongation in its action. Neuron perikarya and proximal axon segments were more vulnerable in diabetes. Neurons exhibited loss of neurofilament labeling, dissolution of the neurons, replacement of neurons with "nests of Nageotte," displacement of nuclei to the periphery of perikarya, and nuclear labeling with TUNEL. Both intraganglionic axons and downstream sural sensory axons developed evidence of axonal degeneration. Local endothelin-induced vasoconstriction of microvessels supplying dorsal root ganglia provides a selective model of ischemia. Diabetic vessels and neurons, exposed to a greater depth and duration of ischemia from endothelin, are especially vulnerable.

Renal Na,K-ATPase structure from cryo-electron microscopy of two-dimensional crystals

The molecular structure of Na,K-ATPase was determined by electron crystallography from two-dimensional crystals induced in purified membranes isolated from the outer medulla of pig kidney. The P2 type unit cell contains two protomers in the E(2) conformation, each of them with a size of 65 x 75 x 150 A(3). The alpha, beta, and gamma subunits in the membrane crystals were demonstrated in the crystals with Western blotting and related to distinct domains in the density map. The alpha subunit corresponds to most of the density in the transmembrane region as well as to the large hydrophilic headpiece on the cytoplasmic side of the membrane. The headpiece is divided into three separated domains. One of these gives rise to an elongated projection onto the membrane plane, while the putative nucleotide binding and phosphorylation domains form compact densities in the rest of the cytoplasmic part of the structure. Density on the extracellular face corresponds to the protein part of the beta subunit. Ten helices from the catalytic a subunit correspond to two groups of distinct densities in the transmembrane region. The structure of the lipid bilayer spanning part also suggests positions for the transmembrane helices from the beta and gamma subunits. The overall structure of the alpha subunit of Na,K-ATPase as determined here by cryo-electron microscopy is similar to the X-ray structure of Ca-ATPase. However, conformational changes between the E(1) and E(2) forms are suggested by different relative positions of cytoplasmic domains.

Effects of growth hormone on renal tubular handling of sodium in healthy humans

To investigate the mechanisms behind the water- and sodium-retaining effects of growth hormone (GH), we studied the effect of GH on 1) water and sodium homeostasis, 2) the renin-angiotensin-aldosterone system (RAAS), and 3) lithium clearance (C(Li)) with and without concomitant prostaglandin (PG) synthesis inhibition with ibuprofen. GH administration for 6 days induced a significant increase in plasma renin, which was abolished by coadministration of ibuprofen (mU x l(-1) x 24 h(-1): control: 22.4 +/- 4.3; GH: 37.7 +/- 8.8; ibuprofen: 15.2 +/- 3.0; GH + ibuprofen: 19.7 +/- 2.5; ANOVA: P < 0.01). Comparable increments in extracellular volume were seen after 6-day treatment with GH alone and in combination with ibuprofen [liters: control, 19.57 +/- 0.92; GH, 20.80 +/- 1.00 (ANOVA: P < 0.0005); ibuprofen, 19.38 +/- 0.90; GH + ibuprofen, 21.63 +/- 1.37 (ANOVA: P < 0.0005)]. Treatment with GH increased C(Li) and changed the tubular handling of sodium and water. The absolute distal sodium reabsorption was increased, and this was only partially counterbalanced by decreased reabsorption in the proximal tubules. The data demonstrate that GH-induced activation of the RAAS can be blocked by concomitant PG synthesis inhibition and that the tubular effects of GH include increased distal nephron sodium and water reabsorption.