A tissue-bioengineering strategy for modeling rare human kidney diseases in vivo

The lack of animal models for some human diseases precludes our understanding of disease mechanisms and our ability to test prospective therapies in vivo. Generation of kidney organoids from Tuberous Sclerosis Complex (TSC) patient-derived-hiPSCs allows us to recapitulate a rare kidney tumor called angiomyolipoma (AML). Organoids derived from TSC2-/- hiPSCs but not from isogenic TSC2+/- or TSC2+/+ hiPSCs share a common transcriptional signature and a myomelanocytic cell phenotype with kidney AMLs, and develop epithelial cysts, replicating two major TSC-associated kidney lesions driven by genetic mechanisms that cannot be consistently recapitulated with transgenic mice. Transplantation of multiple TSC2-/- renal organoids into the kidneys of immunodeficient rats allows us to model AML in vivo for the study of tumor mechanisms, and to test the efficacy of rapamycin-loaded nanoparticles as an approach to rapidly ablate AMLs. Collectively, our experimental approaches represent an innovative and scalable tissue-bioengineering strategy for modeling rare kidney disease in vivo.

Time-resolved molecular dynamics of single and double hydrogen migration in ethanol

Being the lightest, most mobile atom that exists, hydrogen plays an important role in the chemistry of hydrocarbons, proteins and peptides and most biomolecules. Hydrogen can undergo transfer, exchange and migration processes, having considerable impact on the chemical behavior of these molecules. Although much has been learned about reaction dynamics involving one hydrogen atom, less is known about those processes where two or more hydrogen atoms participate. Here we show that single and double hydrogen migrations occurring in ethanol cations and dications take place within a few hundred fs to ps, using a 3D imaging and laser pump-probe technique. For double hydrogen migration, the hydrogens are not correlated, with the second hydrogen migration promoting the breakup of the C-O bond. The probability of double hydrogen migration is quite significant, suggesting that double hydrogen migration plays a more important role than generally assumed. The conclusions are supported by state-of-the-art molecular dynamics calculations.

Variations in pain and function before and after total knee arthroplasty: a comparison between Swedish and Australian cohorts

OBJECTIVE

Preoperative pain and function is viewed as an important predictor of total knee arthroplasty (TKA) outcomes. We examined whether variations in pain and function outcomes existed at 12 months between two centres in Sweden and Australia, and whether this was explained by variations in patient presentation for TKA.

METHODS

This was a retrospective analysis of prospectively collected data. Patients from one centre in Australia (St. Vincent's Hospital (SVH), N = 516) and in Sweden (Trelleborg (TBG), N = 899) who underwent primary TKA between 2012 and 2013. The Western Ontario and McMaster Universities Arthritis Index (WOMAC) was analysed pre- and 12 months' post TKA from which non-response to surgery was determined using the OMERACT-OARSI criteria. Multiple linear regression analysis was used to examine the relationship between change in pain and function and surgery centre, adjusting for preoperative patient characteristics and surgical technique.

RESULTS

Despite worse preoperative outcomes in all subscales of the WOMAC for the SVH cohort, there were no clinically meaningful differences in 12-month WOMAC subscales nor change in WOMAC subscales between SVH and TBG. Almost identical proportions of patients were considered OMERACT-OARSI responders, 85.7% (SVH) and 85.9% (TBG), however for the SVH cohort 25 (4.9%) were moderate and 417 (80.8%) were high responders, compared to the TBG cohort of which 225 (25%) were moderate and 547 (60.9%) were high responders.

CONCLUSION

Despite differences in preoperative presentation between 2 countries, improvements in pain and function and the proportion of individual who responded to TKA surgery at 1 year were similar. Factors related to poor response to TKA surgery require further elucidation.

An examination of the effect of different methods of scoring pain after a total knee replacement on the number of patients who report unchanged or worse pain

We identified a group of patients from the Swedish Arthroplasty Register who reported no relief of pain or worse pain one year after a total knee replacement (TKR). A total of two different patient-reported pain scores were used during this process. We then evaluated how the instruments used to measure pain affected the number of patients who reported no relief of pain or worse pain, and the relative effect of potential risk factors. Between 2008 and 2010, 2883 TKRs were performed for osteoarthritis in two Swedish arthroplasty units. After applying exclusion criteria, 2123 primary TKRs (2123 patients) were included in the study. The Knee injury and Osteoarthritis Outcome Score (KOOS) and a Visual Analogue Scale (VAS) for knee pain were used to assess patients pre-operatively and one year post-operatively. Only 50 of the 220 patients (23%) who reported no pain relief on either the KOOS pain subscale or the VAS for knee pain did so with both of these instruments. Patients who reported no pain relief on either measure tended to have less pain pre-operatively but a higher degree of anxiety. Charnley category C was a predictor for not gaining pain relief as measured on a VAS for knee pain. The number of patients who are not relieved of pain after a TKR differs considerably depending on the instrument used to measure pain.

The Swedish Knee Arthroplasty Register: a review

We are entering a new era with governmental bodies taking an increasingly guiding role, gaining control of registries, demanding direct access with release of open public information for quality comparisons between hospitals. This review is written by physicians and scientists who have worked with the Swedish Knee Arthroplasty Register (SKAR) periodically since it began. It reviews the history of the register and describes the methods used and lessons learned. Cite this article: Bone Joint Res 2014;3:217-22.

Markers of pluripotency and differentiation in human neural precursor cells derived from embryonic stem cells and CNS tissue

Cell transplantation therapies for central nervous system (CNS) deficits such as spinal cord injury (SCI) have been shown to be effective in several animal models. One cell type that has been transplanted is neural precursor cells (NPCs), for which there are several possible sources. We have studied NPCs derived from human embryonic stem cells (hESCs) and human fetal CNS tissue (hfNPCs), cultured as neurospheres, and the expression of pluripotency and neural genes during neural induction and in vitro differentiation. mRNA for the pluripotency markers Nanog, Oct-4, Gdf3, and DNMT3b were downregulated during neural differentiation of hESCs. mRNA for these markers was found in nonpluripotent hfNPC at higher levels compared to hESC-NPCs. However, Oct-4 protein was found in hESC-NPCs after 8 weeks of culture, but not in hfNPCs. Similarly, SSEA-4 and CD326 were only found in hESC-NPCs. NPCs from both sources differentiated as expected to cells with typical features of neurons and astrocytes. The expressions of neuronal markers in hESC-NPCs were affected by the composition of cell culture medium, while this did not affect hfNPCs. Transplantation of hESC-NPC or hfNPC neurospheres into immunodeficient mouse testis or subcutaneous tissue did not result in tumor formation. In contrast, typical teratomas appeared in all animals after transplantation of hESC-NPCs to injured or noninjured spinal cords of immunodeficient rats. Our data show that transplantation to the subcutaneous tissue or the testes of immunodeficient mice is not a reliable method for evaluation of the tumor risk of remaining pluripotent cells in grafts.

Molecular and immunological characterization of Can f 4: a dog dander allergen cross-reactive with a 23 kDa odorant-binding protein in cow dander

BACKGROUND

Dog dander is an important cause of respiratory allergy but its content of allergenic components is still incompletely known. While Can f 1, 2, 3 and 5 have been studied in detail, only fragmentary information is available on the lipocalin Can f 4.

OBJECTIVE

To purify, clone and characterize dog dander allergen Can f 4.

METHODS

Can f 4 was purified from dog dander extract by size exclusion, ion exchange and reverse phase chromatography. A cDNA encoding Can f 4 was cloned and used to produce recombinant Can f 4 in Escherichia coli. A 23 kDa protein from cow dander, displaying cross-reactivity with Can f 4, was purified and identified by amino acid sequencing and mass spectrometry. IgE antibody binding to dog and cow dander extract and to individual dog allergens among 37 dog allergic subjects and 44 pollen allergic controls was studied using ImmunoCAP.

RESULTS

A dog genome segment containing the Can f 4 gene was bioinformatically identified and enabled the cloning of Can f 4 cDNA. Recombinant Can f 4 displayed close immunological and biochemical similarity to purified natural Can f 4 and bound IgE antibodies from 13/37 (35%) sera of dog allergic subjects. Can f 4 reactive sera showed IgE binding to a 23 kDa protein present in cow dander extract, related to a family of odorant-binding proteins. The dog and cow proteins shared 37% sequence identity and their cross-reactivity was demonstrated by IgE inhibition experiments.

CONCLUSION

Recombinant Can f 4 brings the panel of available dog allergens closer to completion and will be important in component-resolved diagnostics in allergy to animal epithelial allergens.

Movement patterns of the C-stem femoral component

We used roentgen stereophotogrammetric analysis to follow 33 C-stem femoral components for two years after primary total hip arthroplasty. All components migrated distally and posteriorly within the cement mantle. The mean distal migration was 1.35 mm (sd 0.62) at two years and the mean posterior migration was 1.35 mm (sd 0.69) at two years. All the femoral components rotated into retroversion with a mean rotation at two years of 1.9° (sd 1.1). For all other directions, the prosthesis was stable up to two years. Compared with other tapered prostheses, the distal migration of the C-stem is the same, but posterior rotation and posterior migration are greater.

Diffuse reflectance spectroscopy of the human tympanic membrane in otitis media

We have investigated if features in the diffuse reflectance spectra from in vivo spectroscopic measurements of the tympanic membrane could aid the diagnosis of otitis media in children. Diffuse reflectance spectroscopy, in the visible wavelength range, was used in 15 ears from children with otitis media with effusion before and after myringotomy and in 15 healthy ears as a reference. Two previously published erythema detection algorithms yielded numerical quantities of haemoglobin content. With a combination of the algorithms, induced erythema (after myringotomy) was distinguished from healthy ears using Student's t-test (p < 0.01). Otitis media with mucous effusion was distinguished from (1) otitis media with serous effusion, (2) induced erythema and (3) healthy ears, (p < 0.05) using Student's t-test for independent groups and the paired t-test for dependent groups. Our results imply that reflectance spectroscopy is a promising technique to be used for the diagnosis of otitis media.

Structure of a high-pressure phase of vanadium pentoxide, β-V2O5

A high-pressure phase of vanadium pentoxide, denoted β-V2O5, has been prepared at P = 6.0 GPa and T = 1073 K. The crystal structure of β-V2O5 has been studied by X-ray and neutron powder diffraction, and high-resolution transmission electron microscopy. The V atoms are six-coordinated within distorted VO6 octahedra. The structure is built up of quadruple units of edge-sharing VO6 octahedra linked by sharing edges along [010] and mutually connected by sharing corners along [001]. This arrangement forms layers of V4O10 composition in planes parallel to (100). The layers are mutually held together by weak forces. β-V2O5 is metastable and transforms to α-V2O5 at 643–653 K under ambient pressure. Structural relationships between β- and α-V2O5, and between β-V2O5 and B-Ta2O5-type structures are discussed. The high-pressure β-V2O5 layer structure can be considered as the parent of a new series of vanadium oxide bronzes with cations intercalated between the layers.

Fibre-optic array for curvature assessment: application in otitis diagnosis

A contact-free sensor consisting of two parallel optical-fibre arrays was designed to assess surface shapes of diffusely scattering media. By sequentially illuminating objects using one fibre array and detecting the diffusely back-scattered photons by the other, a source-detector intensity matrix was formed, where the matrix element (i, j) was the intensity at detector j when light source i was excited. Experimental data from convex and concave polyacetal plastic surfaces were recorded. A mathematical model was used for simulating source-detector intensity matrices for the surfaces analysed in the experiments. Experimental results from the system were compared with the theoretically expected results provided by the mathematical model. The shape and relative amplitude showed similar behaviour in the experiments and simulations. A convex/concave discriminator index D, representing the detected intensity difference between two source-detector separations, was defined. The relative dynamic range of D, defined as the difference between the maximum and the minimum divided by the mean of the index, was 1.37 for convex surfaces and 0.68 for concave surfaces, at a measuring distance of 4.5 mm. The index D was positive for convex surfaces and negative for concave surfaces, which showed that the system could distinguish between convex and concave surfaces, an important result for the diagnosis of otitis media.

Pubertal bone growth in the femoral neck is predominantly characterized by increased bone size and not by increased bone density--a 4-year longitudinal study

Fragility fractures are correlated to reduced bone size and/or reduced volumetric bone density (vBMD). These region-specific deficits may originate from reduced mineral accrual and/or reduced skeletal growth during the first 2 decades of life. Before pathological development can be defined, normal skeletal growth must be described. To evaluate growth of bone size, accrual of bone mineral content (BMC), areal bone mineral density (aBMD) and vBMD in a population-based cohort, 44 boys and 42 girls were followed by annual measurements from the age of 12 to 16 (attendance rates 90-100%). Segmental bone length, bone width, BMC, aBMD and vBMD were measured by dual-energy X-ray absorptiometry (DXA). Data were compared with predicted adult peak, as determined in 36 men aged 27.7+/-4.6 years and 44 women aged 26.8+/-4.9 years. Growth in width of the femoral neck precedes accrual of BMC in the femoral neck in both genders up to age 15. The girls were at all ages closer to their predicted adult peak in both bone width and BMC compared with the boys except in the femoral neck. As femoral neck vBMD had reached its predicted adult peak already at 12 years in both genders, the increase in femoral neck BMC and femoral neck aBMD from age 12 to 16 was most likely to be explained by the increase in bone size. In boys the peak velocity growth was recorded at ~14 years for BMC, height, width and lean mass. Growth from the age of 12 to 16 seems to build a bigger but not a denser skeleton in the femoral neck.

Physical activity increases bone size in prepubertal boys and bone mass in prepubertal girls: a combined cross-sectional and 3-year longitudinal study

This study evaluates the effect on the skeleton of physical activity from age 9 to 16. In 42 girls and 44 boys, bone mass and bone size were evaluated longitudinally by dual-energy X-ray absorptiometry (DXA) from ages 13 to 16. Physical activity from ages 9 to 13 was cross-sectionally evaluated at baseline (age 13). Girls with high physical activity from ages 9 to 13 at baseline had higher femoral neck bone mineral content (FN BMC; g) (P = 0.07), higher FN areal bone mineral density (FN aBMD; g/cm2), and higher FN volumetric BMD (FN vBMD; g/cm3) (both P < 0.05) compared with girls of low activity. FN width (cm) and head aBMD (an unloaded region) showed no differences when comparing the two groups. Three years of further high and low activity (from ages 13 to 16) did not yield any increased differences between the two groups. Boys with high physical activity from ages 9 to 13, had at baseline higher FN BMC, FN aBMD, and FN width (all P < 0.05) compared with boys with low activity. FN vBMD and head aBMD showed no differences when comparing the two groups. Three years of further high and low activity did not yield any increased differences between the two groups. We conclude that exercise may yield skeletal benefits before age 13, and that 3 years of continued high or low level activity up to age 16 did not yield any increased differences in bone size or bone mass in either girls or boys.

Results of hip revision using the Exeter stem, impacted allograft bone, and cement

The Exeter stem and impacted, morselized allograft bone and cement were used in the revisions of 18 consecutive femoral components (17 patients). The primary arthroplasty had been done because of osteoarthritis. All of the femoral components were revised for the first time because of aseptic loosening. The migration pattern of the Exeter stem after revision was studied using roentgen stereophotogrammetric analysis. At 2 years after surgery, all 18 femoral stems had migrated in the distal direction (average, 2.5 mm). In addition, seven of the stems had migrated in the medial direction (average, 1.3 mm), and two stems had migrated in the lateral direction (0.5 mm and 1 mm, respectively). Sixteen of the femoral stems also had migrated in the posterior direction (average, 2.9 mm), but none migrated in the anterior direction. The migration rate decreased gradually with time during the followup. Six femoral stems continued to migrate between 1.5 and 2 years after surgery. In patients with major femoral bone deficiency at the time of hip revision, the use of impacted morselized allograft bone and cement yielded an initial fixation similar to that obtained in conventionally cemented revisions. Pain had improved in all patients at the 2-year followup.

Peripubertal moderate exercise increases bone mass in boys but not in girls: a population-based intervention study

On the basis of cross-sectional studies in elite athletes and longitudinal studies, physical activity in growing children has been suggested to enhance bone mineral acquisition and prevent osteoporosis later in life. The level of exercise in most of these studies is not applicable in a population on a day-to-day basis. The aim of this study was to determine whether moderate increased exercise within the school curriculum from age 12 to 16 years would have anabolic bone effects. In a population-based setting of 40 boys and 40 girls the school curriculum was enhanced to physical education 4 times per week for 3-4 years. Controls were 82 boys and 66 girls who had had physical education twice a week over a corresponding period. Both cases and controls were measured at age 16 years. Bone mineral content (BMC), areal bone mineral density (aBMD), bone size (femoral neck width) and volumetric BMD (vBMD) were measured in total body, spine and femoral neck (FN) by dual-energy X-ray absorptiometry. Data are presented as mean +/- SD. BMC (8 +/- 15%, p = 0.04), aBMD (9 +/- 13%, p = 0.002) and vBMD (9 +/- 15%, p = 0.001) were all higher in FN in the male intervention group compared with controls. FN bone size was no higher in the intervention group than in the controls. In girls, no differences were found when comparing the intervention group with controls. The results remained after adjusting for confounding factors such as weight, height, milk intake and activity after school. In summary, we report that increased bone mass can be achieved in a population-based cohort of boys (but not in girls) by moderate increased physical activity within the school curriculum from age 12 to 16 years. We speculate that the same results can be seen in girls if intervention starts at an earlier age. We conclude that increasing the physical education content of the Swedish school curriculum may improve bone mass in at least peripubertal boys.

Structures and phase transitions of B-Ta2O5 and Z-Ta2O5: two high-pressure forms of Ta2O5

A sample of Ta2O5, ditantalum pentaoxide, heat-treated in a "toroid"-type high-pressure chamber at P = 8 GPa and T = 1470 K, was studied by X-ray powder diffraction and high-resolution transmission electron microscopy (HRTEM). Two high-pressure modifications of Ta2O5, isostructural with B-Nb2O5 and Z-Nb2O5, were identified from the X-ray powder pattern. Both structures were refined by the Rietveld method from the X-ray diffraction data: B-Ta2O5, a = 12.7853 (4), b = 4.8537 (1), c = 5.5276 (2) A, beta = 104.264 (2)degrees, V = 332.45 A3, Z = 4, space group C2/c; Z-Ta2O5, a = 5.2252 (1), b = 4.6991 (1), c = 5.8534 (1) A, beta = 108.200 (2)degrees, V = 136.53 A3, Z = 2, space group C2. The Z-Ta2O5 modification is new. The Ta atoms are six-coordinated in B-Ta2O5 and seven-coordinated in Z-Ta2O5. The two structures are closely related, which makes an intergrowth and a transformation between them possible. An idealized model of the intergrowth structure has been given. The HRTEM study showed defect-rich B-Ta2O5 crystals, which could be interpreted as an intergrowth between the B-Ta2O5 and Z-Ta2O5 phases.

Radiostereometric analysis in hip revision surgery--optimal time for index examination: 6 patients revised with impacted allografts and cement followed weekly for 6 weeks

We revised the hip (6 stems and 5 sockets) with impacted morselized allografts and cement in 6 patients. We followed prosthetic migration by roentgen radiostereometric analysis (RSA) every 7th day for 6 weeks after the first (index) examination performed on the first postoperative day before mobilization. Most of the migration occurred during the first 2 weeks. In most cases more than half of the distal stem migration was seen between the 1st and 14th days. In all cases, the stem and socket migrations slowed down gradually and several prosthetic components had become stable after 5 weeks. We conclude that it is essential to perform the index RSA examination on the 1st or 2nd day after surgery and to state when and how weight bearing should be permitted. Otherwise it will be difficult to compare prosthetic migration in various studies and define normative values for migration predicting survival.

Migration of the acetabular component after revision with impacted morselized allografts: a radiostereometric 2-year follow-up analysis of 21 cases

In a consecutive series of hip revisions due to mechanical loosening, using impacted morselized allografts and cement, we followed 21 acetabular components by radiostereometric analysis (RSA) during 2 years. All but 1 acetabular component migrated in the proximal direction (median 2.1 (0.5-6.4) mm). 6 components migrated in the medial direction (median 0.8 (0.4-1.2) mm) and 6 in the lateral (median 0.8 (0.4-2.0) mm). 14 components migrated in the posterior direction (median 0.8 (0.3-2.3) mm) and 1 in the anterior 0.6 mm. The migration rate gradually decreased in all directions, but 7 acetabular components still migrated in at least 1 direction (median 0.3-0.6 mm) between 1.5 and 2 years postoperatively.

Anthraquinone-induced cell injury: acute toxicity of carminomycin, epirubicin, idarubicin and mitoxantrone in isolated cardiomyocytes

Acute toxic effects of the antineoplastic anthraquinones carminomycin, epirubicin, idarubicin and mitoxantrone were studied in primary cultures of cardiomyocytes, which were isolated from adult rats. Both time- and concentration-dependent changes of cell structure and viability (trypan blue exclusion) following incubation of myocytes with subclinical, clinical and toxic concentrations of the anthraquinones were examined by light microscopy. The area under the decay curve of viable and rod-shaped myocytes was used to express cytotoxicity of the drugs. Mitoxantrone was found to reduce cell viability and number of rod-shaped cells to the greatest extent, followed by carminomycin, idarubicin and epirubicin. A significantly lower accumulation in cardiomyocytes was obtained with epirubicin and idarubicin compared with carminomycin. An inhibitory effect on oxygen consumption by the cells occurred already at 0.1 microM with epirubicin, whereas inhibition caused by other anthraquinones was less pronounced. Our data indicate a weak association of net accumulation and the toxicity parameter IC50 for carminomycin and idarubicin. In contrast to these results, a more significant correlation of cytotoxicity and anthraquinone lipophilicity was found, which suggests that the lipophilic character of a particular anthraquinone may be an important factor in drug-induced acute cardiotoxicity.

β-Al4.5FeSi: A Combined Synchrotron Powder Diffraction, Electron Diffraction, High-Resolution Electron Microscopy and Single-Crystal X-ray Diffraction Study of a Faulted Structure

A previous single-crystal X-ray and electron diffraction structure study [Rømming et al. (1994). Acta Cryst. B50, 307–312] of the heavily faulted alloy phase β-Al4.5FeSi has been extended by synchrotron powder data and further electron microscopy and diffraction observations. Reflections that were omitted in the single-crystal work could be included in the powder refinement, which resulted in some adjustment of cell parameters and atom coordinates. The double c axis reported by some authors is explained by periodic faults in the structure, which is described in terms of a tetragonal sub-unit. Apparent discrepancies between refinement from single-crystal and powder data are discussed briefly.

Comparison of quantitative ultrasound measurements in calcaneus with DXA and SXA at other skeletal sites: a population-based study on 280 children aged 11-16 years

We performed ultrasound measurements (QUS) of the calcaneus in a population-based setting on 280 healthy children, aged 11-16 years, from a small urban area in southern Sweden. The results are compared with dual-energy X-ray absorptiometry (DXA) measurements in the total body, the lumbar spine and the hip, as well as single-energy X-ray absorptiometry (SXA) of the forearm. Normative data and correlations between the three different techniques were determined. We found significant correlations between QUS and age (r = 0.34-0.54), height (r = 0.13-0.56) and weight (r = 0.30-0.60), and between QUS and bone mineral density (BMD) measurements (r = 0.44-0.70). Boys increased all their bone mineral variables with age, whereas girls showed a decreasing trend from age 15 years. QUS had a significantly higher increase in standardized value with age than Ward's triangle BMD, but a significantly lower increase in standardized value with age than distal radius (cortical site) BMD. At other BMD sites we did not find any significant differences compared with QUS regarding changes with age. The measurements obtained by QUS, DXA and SXA, respectively, were divided into, quartiles. Of all subjects in the lowest quartile for QUS measurements, only 34-50% were also in the lowest quartiles for DXA and SXA measurements. In conclusion, QUS measurements of the calcaneus in children show similar results as for adult regarding the correlation with DXA and SXA; they also have a significant correlation with anthropometric data. QUS did not identify the same individuals with low bone mass as the X-ray techniques.

Bone mineral density in adolescents. Higher values in a rural area--a population-based study of 246 subjects in southern Sweden

We performed, in a cross-sectional study, dual energy X-ray absorptiometry (DXA) among 15-16-year-old boys (n 58) and girls (n 44) living in an urban area and among boys (n 82) and girls (n 66) of the same age from a rural area. We measured bone mineral density (BMD) of the total body, the lumbar spine and the hip. In the rural population, we found significantly higher BMD levels in the lumbar spine (14% for the boys and 12% for the girls) and the total body (6.9% for the boys and 3.4% for the girls). We detected no significant differences in the hip BMD. Adolescents in rural areas seem to develop a higher peak bone mass and thereby presumably have a lower risk of developing fragility fractures.

Periprosthetic low-grade hip infections. Erythrocyte sedimentation rate and C-reactive protein in 23 cases

We followed 23 patients from the primary total hip arthroplasty to revision for a bacteriologically proven deep infection with a low virulent organism. The median time to revision was 14 (4-65) months. During this period, the maximum ESR value was median 50 (22-110) mm and the maximum CRP value was 35 (9-95) mg/L. 25 of the 98 CRP values recorded were normal (< 9 mg/L) and 22/89 ESR values were below 30 mm/h. In 6 patients, all CRP values were below 20 mg/L, but 5 of these patients had an ESR > 30 mm. Before the revision, normal values for both tests were found in only 1 patient. Both normal values and slight-to-moderate increases in ESR and/or CRP are consistent with a low-grade periprosthetic hip infection. We recommend that ESR should be determined preoperatively in all patients scheduled for total hip replacement to establish a baseline.

Regional differences in the incidence of insulin-dependent diabetes mellitus among children in Finland from 1987 to 1991. Childhood Diabetes in Finland (DiMe) Study Group

The regional pattern of insulin-dependent diabetes mellitus (IDDM) incidence among children in Finland was analysed applying several methods attempting to describe the geographical variation in occurrence of IDDM. From 1987 to 1991 the number of newly diagnosed cases aged 14 years or less at diagnosis was 1728. The incidence, the incidence rate ratio and the Bayes relative risk (RR) for IDDM were calculated by municipality, by functional area (an urban centre with a subordinated surrounding area) and by area with a population of equal size at risk employing the Geographical Information Systems. The association of IDDM incidence with the degree of urbanization was assessed using the population density as a criterion for the degree of urbanization. The overall mean of the IDDM incidence was 35 per 100000 persons per year. Between municipalities the incidence varied from 4 to 245 per 100000 persons per year, whereas a clear regional pattern was seen among the functional areas and the incidence varied from 26 to 43 per 100000 persons per year. The RR for IDDM among the municipalities ranged from 0.82 to 1.34 and from 0.73 to 1.27 among the functional areas. The incidence determined in four zones with the same size of population was the highest in the middle part of the country. There was a strong inverse correlation between population density and the incidence of IDDM and this also applied to the relationship between child population density and incidence.

Organogenesis of Fascicled ear mutant inflorescences in maize (Poaceae)

The ontogeny of staminate tassels and pistillate ears in the maize mutant Fascicled ear was examined using scanning electron microscopy. The normal pattern of inflorescence development is perturbed by the Fascicled ear mutation at the transition stage. The Fascicled ear mutation promotes the development of an abnormal transition stage axis that is both shorter and broader than the wild type. The inflorescence apical meristem then undergoes a bifurcation, and two inflorescence axes arise in place of a single axis. Each derived inflorescence apical meristem may undergo a similar perturbation sequence. This expression of the Fascicled ear mutation may be repeated one to several times, which leads to the development of a fascicled pistillate inflorescence and a fascicled central spike in the staminate inflorescence. The apical meristems of some tassel branches are also bifurcated. Subsequent organogenesis during paired-spikelet and floral development in Fascicled ear plants follows the pattern of normal maize. However, triplet spikelets are occasionally observed. The organogenic disruption by the Fascicled ear mutation that we describe will aid genetic and molecular analysis on the regulation of inflorescence development in maize and other members of the genus Zea.

`Inverted Twinning' in Intergrowth Tungsten Bronzes

A new type of twinning occurring in intergrowth tungsten bronzes (ITB) is described, revealed by high-resolution electron microscopy. Across the twin boundary the two structure elements of hexagonal tungsten bronze- and tetragonally distorted ReO3-types are interchanged and grow in strict geometrical relationship to each other. The structure is thus `inverted' and in the general case the two `twin' parts represent different members of the structure family. Some members remain invariant upon inversion, however. This defect is most often seen as ribbons in an ITB matrix in Mo-doped samples Cs x Mo y Wl−y O3, which require a lower synthesis temperature than pure tungsten bronzes. They may be frozen-in stages of a slow ordering process. A similar type of twinning might be found in other intergrowth structures.

Structure of UMoO5 studied by single-crystal X-ray diffraction and high-resolution transmission electron microscopy

A combination of X-ray diffraction and high-resolution transmission electron microscopy (HRTEM) has been used to study the crystal structure of molybdenum uranium pentoxide, UMoO5, obtained by hydrothermal and ceramic methods. Crystal data: Mr = 414.0, orthorhombic, Pbaa (number 54), a = 12.746 (1), b = 7.3494 (7), c = 4.1252 (2) Å, V = 386.4 (1) Å3, Z = 4, Dx = 7.116 Mg m−3, R = 0.037 for 723 reflections. The structure of UMoO5 is related to that of UVO5. Both are built up by slabs of pentagonal UO7 bipyramids with slabs of MO6 octahedra in-between. They differ in symmetry due to different types of displacement of the M atoms from the ab plane. The HRTEM study revealed a few defect regions in the UMoO5 crystals prepared by ceramic methods. Energy-dispersive spectroscopy (EDS) analyses indicate a slight excess of uranium in such crystals. Hypothetical models of defect regions are given.

Doxorubicin- and daunorubicin-induced energy deprivation and nucleotide degradation in isolated cardiomyocytes

Cytotoxic mechanisms of the antitumor agents daunorubicin and doxorubicin were elucidated in isolated cardiomyocytes from adult rats. Incubation with daunorubicin resulted in a concentration-dependent loss of cell viability and changes of the cell structure. Only the highest concentration of doxorubicin (1 mM) caused similar effects. Doxorubicin was found to stimulate oxygen consumption by cardiomyocytes (about 20%), while the opposite effect was observed after daunorubicin treatment. A rapid decrease of the mitochondrial ATP content (more than 40%) and elevation of the cytosolic ADP level (doxorubicin 2-fold and daunorubicin 6-fold) was followed by increased release of adenosine and inosine to the surrounding medium. When myocytes were exposed to an anthracycline concentration lower than plasma levels measured clinically (0.15 microM), doxorubicin and daunorubicin significantly decreased the intracellular ADP and NAD levels. Isolated cardiomyocytes were found to be able to form daunorubicinol from daunorubicin. In contrast, no conversion of doxorubicin was detected in our experiments. In conclusion, our data demonstrate that decreased ATP production and increased nucleoside formation are major events in the toxicity induced by daunorubicin and doxorubicin in isolated cardiomyocytes. The results also suggest that the toxic effects may be caused by separate mechanisms.

Hydroperoxide-induced nucleotide degradation and adenosine formation in isolated rat cardiomyocytes

The effect of tert-butyl hydroperoxide (tBH) on the nucleotide level in isolated cardiomyocytes from adult rats was examined. Incubation of myocytes with the hydroperoxide resulted in loss of both ATP and NAD from mitochondria and cytosol. In contrast, only the cytosolic level of NADP was increased. The effect on myocyte content of ADP and AMP was less pronounced. A significant increase in formation and release of adenosine also occurred in tBH-exposed cells. Treatment of cardiomyocytes with tBH resulted in a progressive decline of rod-shaped and viable cells, which was accompanied by an increase in numbers of hypercontracted and round myocytes in the incubation mixture. Electron microscopic examination showed an intense contraction of the cells. In summary our results demonstrate that plasma membrane damage and hypercontraction are early manifestations of tBH-induced injury to isolated cardiomyocytes. The depletion of ATP and formation of adenosine also suggest that degradation of adenine nucleotides may contribute to the cytotoxicity caused by tBH. Possible mechanisms involved in the ATP depletion are discussed.

Effect of moderate ethanol intake on the heart: biochemical and morphological studies with isolated cardiomyocytes from rats fed a low-protein diet

OBJECTIVE

It has been shown that chronic consumption of ethanol can impair myocardial function and result in morphological changes of the heart. The purpose of this work was to evaluate relations between changes in energy metabolism and changes of cell morphology.

METHOD

Long-term effects of moderate ethanol consumption on the heart were examined in isolated cardiomyocytes from rats fed a pellet with low-protein content for 6 months. Digitonin treatment of the cardiomyocytes was used to separate mitochondrial and cytosolic fractions.

RESULTS

A greater fraction of contracted myocytes was isolated from ethanol- and glucose-treated rats, than from rats fed only glucose and/or water as liquid supplement. There were changes of the ultrastructure of myocytes from ethanol and glucose-treated rats, which included mitochondrial degeneration, accumulation of fat droplets and depletion of the glycogen content. An elevated cytosolic level of nucleotides (ATP, ADP and NAD) and disappearance of magnesium from the mitochondrial fraction were observed in myocytes from rats fed ethanol and glucose. The release of adenosine was also found to be inhibited in these cells.

CONCLUSIONS

Our results show that moderate ethanol consumption by rats during protein-restricted conditions produces subclinical changes of cardiomyocyte ultrastructure and alteration of cell morphology. Furthermore, the results indicate that changes of the energy homeostasis in myocytes and inhibition of sarcolemmal adenosine transport are early events that appear to precede the histological alterations.

Immunofluorescence demonstration of digoxin in human myocardial tissue and isolated rat cardiac myocytes with monoclonal antibodies

The aim of the present investigation was to identify the morphological correlates of digoxin binding sites in human heart muscle tissue and isolated viable rat heart myocytes. Cardiac glycoside linked to myocardial cells was demonstrated by monoclonal digoxin specific antibody and by FITC-conjugated anti-mouse immunoglobin serum. This versatile immunofluorescence method can be used in diagnostic and experimental studies of cardiac glycoside binding.

Interferon treatment in patients with malignant carcinoids

Thirteen patients with ileal carcinoids complicated by liver metastases were treated with human leukocyte interferon (IFN) subcutaneously (s.c.) at doses of 3-6 x 10(6) IU/day 5 days weekly during 12 months. Objective tumour response was obtained in 2 patients, based on reduction in tumour size in one patient and on reduction in tumour markers in the other. Stable disease was noted during the 12-month treatment period in 10 patients. Progressive disease was seen in one patient. This patient exhibited tumour growth, new metastases and increases in tumour markers. Among patients with daily flushing prior to treatment, 50% were free of flush after 12 months of IFN. Adverse effects, including a mild influenza-like syndrome, joint and muscle pains, tiredness and reduction of blood cells were observed but did not necessitate long-term dose reductions. Thus, IFN therapy to midgut carcinoid patients resulted in tumour response or stable disease in 12 out of 13 patients without causing severe side effects.

Crystallography of supragingival and subgingival human dental calculus

Selected area electron diffraction of sections and individual crystal fragments of human dental calculus has demonstrated that octacalcium phosphate, hydroxyapatite and whitlockite form the inorganic part of both supragingival and subgingival dental calculus. However, the major constituents in supragingival calculus are platelet-shaped crystals of octacalcium phosphate and needle-shaped crystals of hydroxyapatite, while bulk crystals of whitlockite is the predominant component in subgingival calculus. The subgingival samples seemed to be better crystallized than the supragingival ones. The results obtained by the electron optical and X-ray powder investigations are in good agreement.