Muonic atom spectroscopy with microgram target material

Muonic atom spectroscopy-the measurement of the x rays emitted during the formation process of a muonic atom-has a long standing history in probing the shape and size of nuclei. In fact, almost all stable elements have been subject to muonic atom spectroscopy measurements and the absolute charge radii extracted from these measurements typically offer the highest accuracy available. However, so far only targets of at least a few hundred milligram could be used as it required to stop a muon beam directly in the target to form the muonic atom. We have developed a new method relying on repeated transfer reactions taking place inside a 100 bar hydrogen gas cell with an admixture of 0.25% deuterium that allows us to drastically reduce the amount of target material needed while still offering an adequate efficiency. Detailed simulations of the transfer reactions match the measured data, suggesting good understanding of the processes taking place inside the gas mixture. As a proof of principle we demonstrate the method with a measurement of the 2p-1s muonic x rays from a 5  μ g gold target.

β-Nuclear-Recoil Correlation from ^{6}He Decay in a Laser Trap

We report the first precise measurement of a β-recoil correlation from a radioactive noble gas (^{6}He) confined via a magneto-optical trap. The measurement is motivated by the search for exotic tensor-type contributions to the charged weak current. Interpreted as tensor currents with right-handed neutrinos, the measurements yield |C_{T}/C_{A}|^{2}≤0.022 (90% confidence limit, C.L.). On the other hand, for left-handed neutrinos the limits are 0.007<C_{T}/C_{A}<0.111 (90% C.L.). The sensitivity of the present measurement is mainly limited by experimental uncertainties in determining the time response properties and the distance between the atom cloud and the microchannel plate used for recoil ion detection.

Demonstration of Muon-Beam Transverse Phase-Space Compression

We demonstrate efficient transverse compression of a 12.5  MeV/c muon beam stopped in a helium gas target featuring a vertical density gradient and crossed electric and magnetic fields. The muon stop distribution extending vertically over 14 mm was reduced to a 0.25 mm size (rms) within 3.5  μs. The simulation including cross sections for low-energy μ^{+}-He elastic and charge exchange (μ^{+}↔ muonium) collisions describes the measurements well. By combining the transverse compression stage with a previously demonstrated longitudinal compression stage, we can improve the phase space density of a μ^{+} beam by a factor of 10^{10} with 10^{-3} efficiency.

Measurement of the Permanent Electric Dipole Moment of the Neutron

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26}  e.cm.

Final results for the neutron -asymmetry parameter A0 from the UCNA experiment

The UCNA experiment was designed to measure the neutron β-asymmetry parameter A0 using polarized ultracold neutrons (UCN). UCN produced via downscattering in solid deuterium were polarized via transport through a 7 T magnetic field, and then directed to a 1 T solenoidal electron spectrometer, where the decay electrons were detected in electron detector packages located on the two ends of the spectrometer. A value for A0 was then extracted from the asymmetry in the numbers of counts in the two detector packages. We summarize all of the results from the UCNA experiment, obtained during run periods in 2007, 2008–2009, 2010, and 2011–2013, which ultimately culminated in a 0.67% precision result for A0.

Nuclear structure with radioactive muonic atoms

Muonic atoms have been used to extract the most accurate nuclear charge radii based on the detection of X-rays from the muonic cascades. Most stable and a few unstable isotopes have been investigated with muonic atom spectroscopy techniques. A new research project recently started at the Paul Scherrer Institut aims to extend the highresolution muonic atom spectroscopy for the precise determination of nuclear charge radii and other nuclear structure properties of radioactive isotopes. The challenge to combine the high-energy muon beam with small quantity of stopping mass is being addressed by developing the concept of stopping the muon in a high-density, a high-pressure hydrogen cell and subsequent transfer of the muon to the element of interest. Status and perspectives of the project will be presented.

Search for Neutrinoless Double-β Decay in ^{76}Ge with the Majorana Demonstrator

The Majorana Collaboration is operating an array of high purity Ge detectors to search for neutrinoless double-β decay in ^{76}Ge. The Majorana Demonstrator comprises 44.1 kg of Ge detectors (29.7 kg enriched in ^{76}Ge) split between two modules contained in a low background shield at the Sanford Underground Research Facility in Lead, South Dakota. Here we present results from data taken during construction, commissioning, and the start of full operations. We achieve unprecedented energy resolution of 2.5 keV FWHM at Q_{ββ} and a very low background with no observed candidate events in 9.95 kg yr of enriched Ge exposure, resulting in a lower limit on the half-life of 1.9×10^{25}  yr (90% C.L.). This result constrains the effective Majorana neutrino mass to below 240-520 meV, depending on the matrix elements used. In our experimental configuration with the lowest background, the background is 4.0_{-2.5}^{+3.1}  counts/(FWHM t yr).

The protective effects of social bonding on behavioral and pituitary-adrenal axis reactivity to chronic mild stress in prairie voles

Positive social interactions may protect against stress. This study investigated the beneficial effects of pairing with a social partner on behaviors and neuroendocrine function in response to chronic mild stress (CMS) in 13 prairie vole pairs. Following 5 days of social bonding, male and female prairie voles were exposed to 10 days of CMS (mild, unpredictable stressors of varying durations, for instance, strobe light, white noise, and damp bedding), housed with either the social partner (paired group) or individually (isolated group). Active and passive behavioral responses to the forced swim test (FST) and tail-suspension test (TST), and plasma concentrations of adrenocorticotropic hormone (ACTH) and corticosterone, were measured in all prairie voles following the CMS period. Both female and male prairie voles housed with a social partner displayed lower durations of passive behavioral responses (immobility, a maladaptive behavioral response) in the FST (mean ± SEM; females: 17.3 ± 5.4 s; males: 9.3 ± 4.6 s) and TST (females: 56.8 ± 16.4 s; males: 40.2 ± 11.3 s), versus both sexes housed individually (females, FST: 98.6 ± 12.9 s; females, TST: 155.1 ± 19.3 s; males, FST: 92.4 ± 14.1 s; males, TST: 158.9 ± 22.0 s). Female (but not male) prairie voles displayed attenuated plasma stress hormones when housed with a male partner (ACTH: 945 ± 24.7 pg/ml; corticosterone: 624 ± 139.5 ng/ml), versus females housed individually (ACTH: 1100 ± 23.2 pg/ml; corticosterone: 1064 ± 121.7 ng/ml). These results may inform understanding of the benefits of social interactions on stress resilience. Lay Summary: Social stress can lead to depression. The study of social bonding and stress using an animal model will inform understanding of the protective effects of social bonds. This study showed that social bonding in a rodent model can protect against behavioral responses to stress, and may also be protective against the elevation of stress hormones. This study provides evidence that bonding and social support are valuable for protecting against stress in humans.

White matter integrity, hippocampal volume, and cognitive performance of a world-famous nonagenarian track-and-field athlete

Physical activity (PA) and cardiorespiratory fitness (CRF) are associated with successful brain and cognitive aging. However, little is known about the effects of PA, CRF, and exercise on the brain in the oldest-old. Here we examined white matter (WM) integrity, measured as fractional anisotropy (FA) and WM hyperintensity (WMH) burden, and hippocampal (HIPP) volume of Olga Kotelko (1919-2014). Olga began training for competitions at age of 77 and as of June 2014 held over 30 world records in her age category in track-and-field. We found that Olga's WMH burden was larger and the HIPP was smaller than in the reference sample (58 healthy low-active women 60-78 years old), and her FA was consistently lower in the regions overlapping with WMH. Olga's FA in many normal-appearing WM regions, however, did not differ or was greater than in the reference sample. In particular, FA in her genu corpus callosum was higher than any FA value observed in the reference sample. We speculate that her relatively high FA may be related to both successful aging and the beneficial effects of exercise in old age. In addition, Olga had lower scores on memory, reasoning and speed tasks than the younger reference sample, but outperformed typical adults of age 90-95 on speed and memory. Together, our findings open the possibility of old-age benefits of increasing PA on WM microstructure and cognition despite age-related increase in WMH burden and HIPP shrinkage, and add to the still scarce neuroimaging data of the healthy oldest-old (>90 years) adults.

Mycobacterium chelonae peritonitis in peritoneal dialysis. Literature review

Non-tuberculous mycobacteria are a rare but serious cause of peritoneal dialysis-related peritonitis. There are no clear guidelines for treating non-tuberculous mycobacteria peritoneal dialysis-associated infections. It has been recommended that at least two antibiotics be given for a prolonged period and peritoneal catheter should be removed. This paper describes the clinical course and treatment of a patient with M. chelonae peritoneal dialysis-related peritonitis and reviews the previously published cases.

Combinatory effects of citrinin and ochratoxin A in immortalized human proximal tubule cells

Ochratoxin A (OTA) and citrinin (CIT) are two mycotoxins often occurring together in grains and cereals. Although both are nephrotoxic and can induce apoptosis, combination effects have not been examined up to now. Therefore, the aim of this study was to take a close look at the interactions of citrinin and OTA in cultured human proximal tubule-derived cells (IHKE cells). The cytotoxicity of both mycotoxins was studied, measuring the metabolic activity and the cell number. Furthermore, caspase 3-activation as a marker for apoptosis was examined for both mycotoxin alone and in combination. The results show that citrinin had an antagonistic effect on ochratoxin A induced caspase 3-activation in concentrations of 2.5 and 5 μmol/l. Higher concentrations (7.5 and 15 μmol/l) lead to additive effects, lower citrinin concentrations (0.25 and 1 μmol/l) did not show any effect at all. The observed decrease in caspase 3-activity was specific for the combination with OTA, since the combination of citrinin with cisplatin did not show any effect. Citrinin did not influence of the OTA-induced apoptosis when added two hours after applying ochratoxin A. Also the combination of both toxins decreased the uptake of OTA into the cells which might be an explanation for the antagonistic effect of citrinin in certain concentrations. However, the transport into cells can not be the only explanation. so further examinations are necessary.

Precision measurement of the 6He half-life and the weak axial current in nuclei

Studies of 6He beta decay along with tritium can play an important role in testing ab initio nuclear wave-function calculations and may allow for fixing low-energy constants in effective-field theories. Here, we present an improved determination of the 6He half-life to a relative precision of 3×10(-4). Our value of 806.89±0.11(stat)(-0.19syst)(+0.23)  ms resolves a major discrepancy between previous measurements. Calculating the statistical rate function we determined the ft value to be 803.04(-0.23)(+0.26)  s. The extracted Gamow-Teller matrix element agrees within a few percent with ab initio calculations.

Arrival time and magnitude of airborne fission products from the Fukushima, Japan, reactor incident as measured in Seattle, WA, USA

We report results of air monitoring started due to the recent natural catastrophe on 11 March 2011 in Japan and the severe ensuing damage to the Fukushima Dai-ichi nuclear reactor complex. On 17-18 March 2011, we registered the first arrival of the airborne fission products (131)I, (132)I, (132)Te, (134)Cs, and (137)Cs in Seattle, WA, USA, by identifying their characteristic gamma rays using a germanium detector. We measured the evolution of the activities over a period of 23 days at the end of which the activities had mostly fallen below our detection limit. The highest detected activity from radionuclides attached to particulate matter amounted to 4.4 ± 1.3 mBq m(-3) of (131)I on 19-20 March.

Search for an annual modulation in a p-type Point Contact germanium dark matter detector

Fifteen months of cumulative CoGeNT data are examined for indications of an annual modulation, a predicted signature of weakly interacting massive particle (WIMP) interactions. Presently available data support the presence of a modulated component of unknown origin, with parameters prima facie compatible with a galactic halo composed of light-mass WIMPs. Unoptimized estimators yield a statistical significance for a modulation of ∼2.8σ, limited by the short exposure.

Test of Lorentz invariance with spin precession of ultracold neutrons

A clock comparison experiment, analyzing the ratio of spin precession frequencies of stored ultracold neutrons and 199Hg atoms, is reported. No daily variation of this ratio could be found, from which is set an upper limit on the Lorentz invariance violating cosmic anisotropy field b perpendicular < 2 x 10(-20) eV (95% C.L.). This is the first limit for the free neutron. This result is also interpreted as a direct limit on the gravitational dipole moment of the neutron |gn| < 0.3 eV/c2 m from a spin-dependent interaction with the Sun. Analyzing the gravitational interaction with the Earth, based on previous data, yields a more stringent limit |gn| < 3 x 10(-4) eV/c2 m.

Birmingham Hip Resurfacing arthroplasty: short-term clinical and radiographic outcome

BACKGROUND

Aim of our study was to evaluate the clinical and radiographic outcome of the first 300 consecutively implanted Birmingham Hip Resurfacing arthroplasties (BHR) in our department.

METHODS

300 BHR arthroplasties were performed in 263 patients until May 2003. Primary clinical endpoints of the investigation were the implant survival and the total Harris hip score, assessed at the last examination.

RESULTS

At a median follow-up time of 24 months the Kaplan/Meier survivor estimate was 98%. 6 implant revisions were performed due to infection (2), malposition (1), femoral neck fracture (1), primary unstable cup (1) and chronic pain (1), respectively. The median Harris hip score improved from 51 points to 96 points at last follow-up. No hip showed radiographic signs of aseptic implant loosening.

CONCLUSIONS

The preliminary experience with the BHR for the younger adult requiring hip arthroplasty is encouraging, but has to be reproduced in the long-term.

Direct experimental verification of neutron acceleration by the material optical potential of solid 2H2

We have measured the acceleration of neutrons by the material optical potential of solid 2H2. Using a gravitational spectrometer, we find a minimal kinetic energy Ec = (99+/-7) neV of neutrons from a superthermal ultracold neutron (UCN) source with solid 2H2 as an UCN converter. The result is in excellent agreement with theoretical predictions, Ec = 106 neV.

Cold neutron energy dependent production of ultracold neutrons in solid deuterium

A measurement of the production of ultracold neutrons from velocity-selected cold neutrons on gaseous and solid deuterium targets is reported. The expected energy dependence for two-particle collisions with well defined neutron and Maxwell-Boltzmann distributed molecular velocities is found for the gas target. The solid target data agree in shape with the phonon density-of-states curve and provide strong evidence for the phonon model including multiphonon excitations.

Direct experimental limit on neutron-mirror-neutron oscillations

In case a mirror world with a copy of our ordinary particle spectrum would exist, the neutron n and its degenerate partner, the mirror neutron n', could potentially mix and undergo nn' oscillations. The interaction of an ordinary magnetic field with the ordinary neutron would lift the degeneracy between the mirror partners, diminish the n' amplitude in the n wave function and, thus, suppress its observability. We report an experimental comparison of ultracold neutron storage in a trap with and without superimposed magnetic field. No influence of the magnetic field is found and, assuming negligible mirror magnetic fields, a limit on the oscillation time taunn' > 103 s (95% C.L.) is derived.

Oberfl�chenersatz am H�ftgelenk

Currently, an increase in resurfacing arthroplasty in the treatment of hip osteoarthritis--especially in young adults--can be observed. New bearing technologies (mainly metal-on-metal surfaces) show better tribologic results than historical designs (e.g. the Wagner cup). At present, it is unclear whether these modifications and a definitively low dislocation rate--due to the large head diameter--can be supported by further good clinical results. The quantity as well as the quality of the available investigations prevents a definite opinion at the moment. Appropriate clinical studies with documented radiographic follow-up are necessary to compare the outcome of these new implants with standard techniques.

H�ftgelenk-Oberfl�chenersatzendoprothesen

In comparison to stemmed total hip replacements, hip resurfacing offers advantages especially in joint stability and amount of femoral bone resection. After the poor results achieved with this concept that were mainly caused by failure of the materials used, reintroduction of the metal-on-metal bearing initiated a renaissance. This bearing, the cementless cup, and the improved surgical technique led to better short- to medium-term results. Revision and complication rates are now comparable to conventional total hip replacements. The functional capacity of the method is higher. Because long-term results are not available, however, questions remain, for instance, the consequences of the higher metal ion serum concentrations or the impossibility of changing the inlay when femoral revision becomes necessary.

Funktionelle Behandlungsergebnisse nach Oberflächenersatz am Hüftgelenk: Vergleich zwischen Dysplasie- und idiopathischer Koxarthrosen

AIM

To determine if there are differences in function after resurfacing arthroplasty of the hip in patients with primary osteoarthritis compared to patients with secondary osteoarthritis due to developmental dysplasia of the hip.

METHOD

In a controlled prospective study of Birmingham Hip Resurfacing (BHR) we included all patients with primary osteoarthritis (n = 54, average age 48.4 years) and osteoarthritis due to high grade dysplasia (Eftekhar B, n = 34, average age 55.8 years). Standardized clinical (Harris hip score) and radiographic examinations were performed 6 weeks, 3 months and 6 months and then every year after the operation.

RESULTS

All patients could be followed up to 1.5 years (1-4 years) after surgery. The average Harris hip score improved to 82-95 points in both groups 3 months postoperatively. Statistically significant differences could be found in the subscales "function" and "limp", where patients with dysplastic hips showed somewhat lower results after 6 (function) to 12 weeks (limp) postoperatively. This is probably attributable to extended non-weight-bearing after acetabular reconstruction in these cases, as the difference disappeared with full weight-bearing. Radiographically determined neck-shaft angles are slightly higher in dysplastic hips (142 degrees versus 135 degrees ), but we did not recognize any significant differences in implant positioning.

CONCLUSION

The short- to mid-term results showed no clinically relevant functional differences after surface replacement in patients with primary osteoarthritis of the hip and patients with secondary osteoarthritis due to higher grade dysplasia. Long-term observation is necessary, however, to determine if these positive functional results are reflected by appropriate radiographic survival.

Secondary prevention with antioxidants of cardiovascular disease in endstage renal disease (SPACE): randomised placebo-controlled trial

BACKGROUND

Excess cardiovascular mortality has been documented in chronic haemodialysis patients. Oxidative stress is greater in haemodialysis patients with prevalent cardiovascular disease than in those without, suggesting a role for oxidative stress in excess cardiovascular disease in haemodialysis. We investigated the effect of high-dose vitamin E supplementation on cardiovascular disease outcomes in haemodialysis patients with pre-existing cardiovascular disease.

METHODS

Haemodialysis patients with pre-existing cardiovascular disease (n=196) aged 40-75 years at baseline from six dialysis centres were enrolled and randomised to receive 800 IU/day vitamin E or matching placebo. Patients were followed for a median 519 days. The primary endpoint was a composite variable consisting of: myocardial infarction (fatal and non-fatal), ischaemic stroke, peripheral vascular disease (excluding the arteriovenous fistula), and unstable angina. Secondary outcomes included each of the component outcomes, total mortality, and cardiovascular-disease mortality.

FINDINGS

A total of 15 (16%) of the 97 patients assigned to vitamin E and 33 (33%) of the 99 patients assigned to placebo had a primary endpoint (relative risk 0.46 [95% CI 0.27-0.78], p=0.014). Five (5.1%) patients assigned to vitamin E and 17 (17.2%) patients assigned to placebo had myocardial infarction (0.3 [0.11-0.78], p=0.016). No significant differences in other secondary endpoints, cardiovascular disease, or total mortality were detected.

INTERPRETATION

In haemodialysis patients with prevalent cardiovascular disease, supplementation with 800 IU/day vitamin E reduces composite cardiovascular disease endpoints and myocardial infarction.

Successful treatment of secondary hyperparathyroidism in hemodialysis patients with oral pulse 1-alpha-hydroxy-cholecalciferol therapy

We have used high-dose oral pulse therapy with 1 alpha-hydroxycholecalciferol (1 alpha-OH-D3) to treat 40 hemodialysis patients suffering form secondary hyperparathyroidism. Forty patients with intact parathyroid hormone (PTH) levels of > 150 pg/ml were treated with 4 micrograms oral 1 alpha-OH-D3 twice weekly for 1 year. The mean PTH level was 515 +/- 50 pg/ml prior to treatment, which fell to 191 +/- 42 pg/ml after 6 months of treatment (p < 0.00001), and to 164 +/- 39 pg/ml after 12 months of treatment. Patients with very high PTH levels (> 800 pg/ml) suppressed less well than patients with lower levels (150-300 pg/ml). The therapeutic end point of PTH < 100 pg/ml was achieved in 23 patients (58%). The main side effect of the treatment was hypercalcemia, but this was symptomatic in only 3 patients, all above the age of 70 years. In summary, oral high-dose pulse therapy with 1 alpha-OH-D3 was highly effective in suppressing PTH levels in hyperparathyroid hemodialysis patients, and side effects were relatively few.

Glycerol induced ARF in rats is mediated by tumor necrosis factor-alpha

Glycerol-induced acute renal failure (ARF) in rats is a model of acute trauma in which intra-muscular injection of 50% glycerol causes rapid myoglobinuria, oliguria, and a rapid reduction in glomerular filtration rate. We found that plasma tumor necrosis factor-alpha (TNF-alpha) is rapidly induced in glycerol injected rats. It can be detected in some animals as early as 30 minutes post-injection, peaks at one hour (range: 4 to 32 U/ml) with no significant difference between blood from renal vein and vena cava, and decreases by three hours. None was detected in control saline injected rats (P < 0.001). Four out of five rats infused with neutralizing anti-TNF-alpha antiserum (200 microliters/300 g body wt) immediately prior to glycerol injection had significantly protected kidney function (P = 0.001). In these rats, plasma urea (104.8 +/- 58.9 mg%) and creatinine (1.16 +/- 0.38 mg%) were lower and creatinine clearance higher (0.34 +/- 011 ml/min) than in glycerol injected animals pretreated with normal serum (291.8 +/- 41.8 mg%, 3.15 +/- 0.74 mg%, and 0.03 +/- 0.03 ml/min, respectively) or animals injected with glycerol alone (302.6 +/- 76.8 mg%, 3.45 +/- 0.97 mg%, and 0.03 +/- 0.03 ml/min, respectively). These results imply a direct role for TNF-alpha in pathogenesis of glycerol induced ARF in rats.

Inhalation therapy: alternative systems--an overview

Three possibilities exist, in principle, to apply medication by inhalation: (1) Inhalation from Pressurized Metered Dose Inhalers (2) Direct Inhalation of Dry Powder (3) Inhalation of Nebulized Aqueous Solutions. Chlorofluorocarbons that are necessary for pressurized metered dose inhalers have unwanted environmental properties. Therefore, alternative gases are being developed (HFA-134a and HFA 227) on the premise that pressurized metered dose aerosols in airways therapy have distinct advantages which are reflected in the high acceptance and application of these MDIs worldwide. Dry powder inhalation requires sophisticated devices to provide for exact dosing. For nebulizers the major problem was their size and consequently their restricted use. Multi-dose pocket-size systems are on the market for (1) and (2). For nebulization such a system is currently being introduced. A critical comparison of benefits and disadvantages of the existing drug delivery systems to the airways leads to the conclusion that all three modes will remain essential to cover the therapeutic needs for a wide variety of drugs and patient populations.

Fibroblasts of rabbit kidney in culture. I. Characterization and identification of cell-specific markers

There is currently no information available as to whether different renal fibroblast subpopulation can be identified and whether they show differences in functional properties. We therefore compared the growth characteristics of interstitial fibroblasts derived from the rabbit renal cortex and inner medulla (papilla) and sought cell-specific markers for the two populations of cells. Analyses of the population dynamics revealed that the mitotic lifespan of papillary fibroblasts (PF) is approximately 50% longer than that of cortical fibroblasts (CF), with the former going through 20 cumulative population doublings (CPD) before transition into terminally differentiated postmitotic cells compared with 9 CPD in CF. PF and CF populations contained three types of mitotically active cells (MFI, MFII, MFIII) and three types of postmitotic cells (PMFIV, PMFV, PMFVI) differentiating along a terminal cell lineage from MFI through PMFVI. In both PF and CF cultures the percent of MF-type cells decreased and the percent of postmitotic cells increased with successive doublings. Two-dimensional polyacrylamide gel electrophoresis of uniform clonal populations of MFIII-type cells revealed two specific proteins for PF-MFIII-type cells, pf1 and pf2, and three specific proteins for CF-MFIII-type cells, cf1, cf2, and cf3. Additionally, a monoclonal antibody was raised that does not recognize CF in culture, but reacts strongly with PF. These studies demonstrate that rabbit renal PF have a pattern of growth in vitro that is distinct from that of CF and that they can be positively identified by specific immunological and protein markers in vitro.

Fibroblasts of rabbit kidney in culture. II. Paracrine stimulation of papillary fibroblasts by PDGF

To examine the role of tubulointerstitial cell interaction in the regulation of fibroblast growth, fibroblasts from the rabbit renal cortex (CF) and papilla (PF) were cocultured with epithelial cells from the same tissue location. Inner medullary collecting duct epithelial cells (IMCDE) or IMCDE-conditioned medium stimulated DNA synthesis in PF, whereas proximal tubule epithelium (PTE) had no effect on the proliferation of CF. PF and CF showed a similar mitogenic response to exogenous epidermal growth factor and insulin-like growth factor 1 (IGF-I). Transforming growth factor-beta 1 inhibited growth of both cell types, and basic fibroblast growth factor (bFGF) had no effect on proliferation of either cell type. In contrast, platelet-derived growth factor (PDGF) was a potent mitogen for PF but was only weakly mitogenic for CF. Both CF and PF expressed a similar number of a single-affinity class of PDGF receptors (Kd, 2-4 x 10(-10) M). Assay for growth factor activity in conditioned medium from IMCDE and PTE showed that only IMCDE produced detectable PDGF. IMCDE-stimulated proliferation of PF was partially blocked by an antibody to PDGF, whereas antibodies to IGF-I had no neutralizing effect. The data suggest a role for PDGF in the regulation of interstitial fibroblast proliferation by IMCDE in the renal papilla. This paracrine system may be important in the pathogenesis of some forms of interstitial fibrosis of the kidney.

Levels and correlates of blood pressure in recent and earlier Ethiopian immigrants to Israel

Blood pressure (BP) and anthropometric data were collected on 483 recent immigrants from Ethiopia to Israel, and on 171 adults and 100 adolescent boarding school students who had immigrated two to three years earlier. Comparison of samples within the Ethiopian groups, and between new and early Ethiopian immigrants with Israel and resident Israelis revealed the following: Systolic and diastolic BP were considerably lower in recent immigrants of both sexes than among counterparts residing in Israel for two to three years. The latter group significantly approached, but did not reach, the BP levels of veteran Israelis. A similar comparison of 100 immigrant Ethiopian boarding school children with an Israeli high school population revealed apparently larger differences among the boys than the girls, whose BP was 'adapted' to a greater degree. Differences in relative weight paralleled those identified for BP, with the Quetelet index (QI) progressively higher when comparing new immigrants with earlier ones, and with persons who have lived in Israel for a longer period. Whether the weight differences provide a complete explanation for BP changes cannot be definitely stated, pending prospective data on weight and BP changes. Correlations of BP with anthropometric parameters and pulse rate indicated that weight rather than QI was the stronger correlate of BP in adults, whereas weight and height, but not QI, correlated with BP in adolescent boys. QI correlated with BP in adolescent, apparently sexually mature girls, but not in boys.

Blood pressure in Ethiopian immigrants in Israel: comparison with resident Israelis

Blood pressure was examined in 483 Ethiopian immigrants a few weeks after their arrival in Israel. The results were compared with those from a group of 171 Ethiopian immigrants who came to Israel 2-3 years earlier. Mean blood pressure was significantly higher in the veteran immigrants, whose weight was also greater. Both groups had lower blood pressure than the resident Israeli population.

Castleman's disease. An uncommon computed tomographic feature

A case of localized intrathoracic Castleman tumor demonstrated, on CT scan, calcifications in a circumferential distribution. The prevalence of calcifications in Castleman's disease and the differential diagnosis of the above unusual CT findings are discussed.

Uncommon presentation of pheochromocytoma: case studies

Twelve patients with pheochromocytoma have shown unusual clinical and laboratory presentation. These include three patients with cardiac manifestations (sick sinus syndrome, obstructive cardiomyopathy and ischemic ECG changes). Two patients with gastrointestinal problems (acute abdomen due to ischemic bowel and constipation). One child with sudden blindness and one, non diabetic patient with polyuria. Laboratory findings included four patients with diabetes mellitus, four patients with hypercalcemia two of them with concomitant hyperreninemia and one patient with hypokalemia. Awareness of the illness leads to the discovery of unusual cases and even a most severely sick patient can make a complete recovery.

Enalapril in the treatment of renovascular hypertension

Enalapril, an angiotensin converting enzyme (ACE) inhibitor, was given to 12 patients with renovascular hypertension: To five of them as a single drug after discontinuing other medications, and to seven patients as a substitute for one of their previous medications. The drug proved effective in controlling hypertension in all patients. Flushing and palpitations occurred in two of them, one of whom also showed a rise in creatinine and mild hyperkalemia. Two patients who had developed side effects while on captopril (renal deterioration in one, and severe rash in the other) tolerated enalapril well. Enalapril effectively reduced the blood pressure in the one patient with bilateral renal artery stenosis without causing renal failure.

Clinical use of captopril in Takayasu's disease

Three patients with Takayasu's disease (TD), initially observed with hypertension and/or congestive heart failure, were treated with captopril, an orally active inhibitor of converting enzyme. As arteritis in this disease is diffuse and extensive, surgical correction of renovascular hypertension is often delayed or impossible. Our experience enables us to recommend captopril for conservative treatment in TD.

Computerized tomography in the diagnosis of congenital hepatic fibrosis

A case of congenital hepatic fibrosis (CHF), a relatively rare disease, was diagnosed preoperatively on the basis of clinical and radiological findings. The diagnosis was confirmed by computerized tomography and later proven by a liver biopsy performed during cholecystectomy. Increased awareness of this entity may reveal heretofore unidentified cases of CHF.

Use of oral converting enzyme inhibitor, captopril for lateralizing renal venous renin activity

Captopril was administered prior to renal vein renin sampling in an attempt to select patients amenable to surgical treatment for renin dependent hypertension. Renal venous blood for plasma renin activity was taken only after captopril stimulation. Sampling from the antecubital vein before and after this provocation showed a marked rise in renin, thereby confirming the efficacy of the test. Elimination of the initial selective renal vein sampling shortens the catheterization period without affecting the accuracy and dependability of the procedure.

Captopril, an orally active angiotensin I converting enzyme inhibitor in the treatment of renovascular and essential hypertension

The hypotensive response to captopril is described for 12 hypertensive patients, 7 of whom had renovascular hypertension. The drug was effective in lowering blood pressure. The few reversible adverse reactions that occurred included loss of the sense of taste in one patient and rash and fever in another. Three patients with renal failure showed deterioration of renal function during treatment, suggesting the advisability of treating such cases with lower dosages.

Comparison of radioimmunoassay and counterimmunoelectrophoresis for the detection of hepatitis B surface antigen carriers in a high-prevalence region

Solid-phase radioimmunoassay (RIA) and counterimmunoelectrophoresis (CIE) were compared for the detection of hepatitis B surface antigen (HBsAg) carriers among blood donors in Jerusalem, which is in a region characterized by a high prevalence of HBsAg and a predominance of the ayw subtype. RIA detected 84% more HBsAg carriers than CIE, with the resultant exclusion of 1.8 times as many potentially infective donors. The results provide additional information concerning the specific increases in donor-carrier detection that are associated with the introduction of highly sensitive HBsAg tests in different geographic and epidemiologic circumstances.