Introduction of continuous glucose monitoring (CGM) is a key factor in decreasing HbA1c in war refugee children with type 1 diabetes

AIMS

Our aim was to describe the changes in therapy and diabetes control in Ukrainian war refugee children with diabetes (CwD) during the first year of their stay in Czechia.

METHODS

A total of 124 CwD (62 male, 62 female) were enrolled into this observational study. Anthropometric, laboratory and diabetes management data were acquired at baseline and at 3 months intervals for 12 months. All CwD were offered a CGM device during their first visit. Generalized Estimating Equation models were fitted in order to estimate the dynamics of studied characteristics.

RESULTS

Median baseline HbA1c was 58 mmol/mol (IQR [48; 73]mmol/mol) (7.5 %, IQR[6.5;8.8]%). The HbA1c decreased significantly throughout the course of the study at a pace of - 2.2 mmol/mol (-0.2 %pt.) per visit (P = 0.01, CI[-3.2;-1.1]). The pace of the decrease in the average HbA1c was significantly higher in the group of CwD who received CGM in Czechia than in those who already had it from Ukraine by 2.9 mmol/mol (0.27 %pt.) per visit (P < 0.001, CI [-4.4; -1.3]).

CONCLUSIONS

The steepest decrease in HbA1c was observed in CwD with newly initiated CGM underlining its vital role in improving the glucose control of CwD regardless of their background.

Phosphatidylinositol 4-kinase IIIβ mediates contraction-induced GLUT4 translocation and shows its anti-diabetic action in cardiomyocytes

In the diabetic heart, long-chain fatty acid (LCFA) uptake is increased at the expense of glucose uptake. This metabolic shift ultimately leads to insulin resistance and a reduced cardiac function. Therefore, signaling kinases that mediate glucose uptake without simultaneously stimulating LCFA uptake could be considered attractive anti-diabetic targets. Phosphatidylinositol-4-kinase-IIIβ (PI4KIIIβ) is a lipid kinase downstream of protein kinase D1 (PKD1) that mediates Golgi-to-plasma membrane vesicular trafficking in HeLa-cells. In this study, we evaluated whether PI4KIIIβ is involved in myocellular GLUT4 translocation induced by contraction or oligomycin (an F₁F₀-ATP synthase inhibitor that activates contraction-like signaling). Pharmacological targeting, with compound MI14, or genetic silencing of PI4KIIIβ inhibited contraction/oligomycin-stimulated GLUT4 translocation and glucose uptake in cardiomyocytes but did not affect CD36 translocation nor LCFA uptake. Addition of the PI4KIIIβ enzymatic reaction product phosphatidylinositol-4-phosphate restored oligomycin-stimulated glucose uptake in the presence of MI14. PI4KIIIβ activation by PKD1 involves Ser294 phosphorylation and altered its localization with unchanged enzymatic activity. Adenoviral PI4KIIIβ overexpression stimulated glucose uptake, but did not activate hypertrophic signaling, indicating that unlike PKD1, PI4KIIIβ is selectively involved in GLUT4 translocation. Finally, PI4KIIIβ overexpression prevented insulin resistance and contractile dysfunction in lipid-overexposed cardiomyocytes. Together, our studies identify PI4KIIIβ as positive and selective regulator of GLUT4 translocation in response to contraction-like signaling, suggesting PI4KIIIβ as a promising target to rescue defective glucose uptake in diabetics.

Early disease course is unaltered in mucopolysaccharidosis type IIIA (MPS IIIA) mice lacking α-synuclein

BACKGROUND

Sanfilippo syndrome (mucopolysaccharidosis type IIIA; MPS IIIA) is an inherited paediatric-onset neurodegenerative disorder caused by the lysosomal deficiency of sulphamidase with subsequent accumulation of heparan sulphate. The pathological mechanisms responsible for clinical disease are unknown; however, intraneuronal accumulation of aggregation-prone proteins such as α-synuclein, phosphorylated tau and amyloid precursor protein suggests inefficient intracellular trafficking and lysosomal degradation.

AIM

To investigate the contribution the accumulating α-synuclein plays in early symptom emergence that is, impaired cognition, reduced anxiety and motor deficits, first detectable between 3-5 months of age.

METHODS

We have crossed congenic MPS IIIA mice with α-synuclein-deficient (Snca^tm1Rosl /J) mice and evaluated phenotype and brain disease lesions.

RESULTS

In a battery of behavioural tests performed on mice aged 12-22 weeks, we were unable to differentiate α-synuclein-deficient MPS IIIA mice from those with one or both copies of the α-synuclein gene; all three affected genotypes were significantly impaired in test performance when compared to wild-type littermates. Histological studies revealed that the rate, location and nature of deposition of other proteinaceous lesions, the disruption to endolysosomal protein expression and the inflammatory response seen in the brain of α-synuclein-deficient MPS IIIA mice reflected that seen in MPS IIIA mice homo- or heterozygous for α-synuclein.

CONCLUSION

Deletion and/or deficiency of α-synuclein does not influence clinical and neuropathological disease progression in murine MPS IIIA, demonstrating that in and of itself, this protein does not initiate the cognitive and motor symptoms that occur in the first 5 months of life in MPS IIIA mice.

Semen collection and artificial insemination in cockatiels (Nymphicus hollandicus) – A potential model for psittacines

Study: Since many psittacine species are endangered and also rare in captivity, the number of offspring produced from breeding is crucial. Many potential breeding birds in species conservation programs are force-paired, and the eggs of many clutches are frequently infertile. Furthermore, male infertility is a common problem. The use of artificial insemination may increase the number of fertile eggs. Material and methods: In this study, 32 cockatiels (Nymphicus hollandicus) were divided into two groups. In one group, the males were endoscopically sterilised. The males of the other group were used as semen donors. After collection using a novel massage technique, semen samples were examined microscopically to assess contamination and quality. Samples with medium to high sperm concentrations, medium to high motility and no contaminants were used for intracloacal artificial insemination of hens in the group with sterile males. Results: In total, 74.2% of all attempts to collect semen were successful. Insemination resulted in fertilisation of 17 of 23 eggs (73.9%), which was slightly lower than the natural fertilisation rate (88.4%). No negative effects were observed on the oviposition interval of the inseminated hens throughout the entire study. Clinical relevance: Easily applicable in veterinary practice, this study demonstrates that the use of artificial insemination may be a valuable tool to address reproductive failure of psittacines in breeding projects.

Salarin C inhibits the maintenance of chronic myeloid leukemia progenitor cells

We previously showed that incubation of chronic myeloid leukemia (CML) cells in very low oxygen selects a cell subset where the oncogenetic BCR/Abl protein is suppressed and which is thereby refractory to tyrosine kinase inhibitors used for CML therapy. In this study, salarin C, an anticancer macrolide extracted from the Fascaplysinopsis sponge, was tested as for its activity on CML cells, especially after their incubation in atmosphere at 0.1% oxygen. Salarin C induced mitotic cycle arrest, apoptosis and DNA damage. Salarin C also concentration-dependently inhibited the maintenance of stem cell potential in cultures in low oxygen of either CML cell lines or primary cells. Surprisingly, the drug also concentration-dependently enforced the maintenance of BCR/Abl signaling in low oxygen, an effect which was paralleled by the rescue of sensitivity of stem cell potential to IM. These results suggest a potential use of salarin C for the suppression of CML cells refractory to tyrosine kinase inhibitors.

Semen collection and artificial inseminationin cockatiels (Nymphicus hollandicus)--a potential model for psittacines

STUDY

Since many psittacine species are endangered and also rare in captivity, the number of offspring produced from breeding is crucial. Many potential breeding birds in species conservation programs are force-paired, and the eggs of many clutches are frequently infertile. Furthermore, male infertility is a common problem. The use of artificial insemination may increase the number of fertile eggs.

MATERIAL AND METHODS

In this study, 32 cockatiels (Nymphicus hollandicus) were divided into two groups. In one group, the males were endoscopically sterilised. The males of the other group were used as semen donors. After collection using a novel massage technique, semen samples were examined microscopically to assess contamination and quality. Samples with medium to high sperm concentrations, medium to high motility and no contaminants were used for intracloacal artificial insemination of hens in the group with sterile males.

RESULTS

In total, 74.2% of all attempts to collect semen were successful. Insemination resulted in fertilisation of 17 of 23 eggs (73.9%), which was slightly lower than the natural fertilisation rate (88.4%). No negative effects were observed on the oviposition interval of the inseminated hens throughout the entire study.

CLINICAL RELEVANCE

Easily applicable in veterinary practice, this study demonstrates that the use of artificial insemination may be a valuable tool to address reproductive failure of psittacines in breeding projects.

Finite dose skin mass balance including the lateral part: comparison between experiment, pharmacokinetic modeling and diffusion models

This work investigates in vitro finite dose skin absorption of the model compounds flufenamic acid and caffeine experimentally and mathematically. The mass balance in different skin compartments (donor, stratum corneum (SC), deeper skin layers (DSL), lateral skin parts and acceptor) is analyzed as a function of time. For both substances high amounts were found in the lateral skin compartment after 6h of incubation, which emphasizes not to elide these parts in the modeling. Here, three different mathematical models were investigated and tested with the experimental data: a pharmacokinetic model (PK), a detailed microscopic two-dimensional diffusion model (MICRO) and a macroscopic homogenized diffusion model (MACRO). While the PK model was fitted to the experimental data, the MICRO and the MACRO models employed input parameters derived from infinite dose studies to predict the underlying diffusion process. All models could satisfyingly predict or describe the experimental data. The PK model and MACRO model also feature the lateral parts.

Erythropoietin-driven signalling and cell migration mediated by polyADP-ribosylation

Background:

Recombinant human erythropoietin (EPO) is the leading biotechnology engineered hormone for treatment of anaemia associated with chronic conditions including kidney failure and cancer. The finding of EPO receptors on cancer cells has raised the concern that in addition to its action in erythropoiesis, EPO may promote tumour cell growth. We questioned whether EPO-induced signalling and consequent malignant cell manifestation is mediated by polyADP-ribosylation.

Methods:

Erythropoietin-mediated PARP (polyADP-ribose polymerase-1) activation, gene expression and core histone H4 acetylation were examined in UT7 cells, using western blot analysis, RT–PCR and immunofluorescence. Erythropoietin-driven migration of the human breast epithelial cell line MDA-MB-435 was determined by the scratch assay and in migration chambers.

Results:

We have found that EPO treatment induced PARP activation. Moreover, EPO-driven c-fos and Egr-1 gene expression as well as histone H4 acetylation were mediated via polyADP-ribosylation. Erythropoietin-induced cell migration was blocked by the PARP inhibitor, ABT-888, indicating an essential role for polyADP-ribosylation in this process.

Conclusions:

We have identified a novel pathway by which EPO-induced gene expression and breast cancer cell migration are regulated by polyADP-ribosylation. This study introduces new possibilities regarding EPO treatment for cancer-associated anaemia where combining systemic EPO treatment with targeted administration of PARP inhibitors to the tumour may allow safe treatment with EPO, minimising its possible undesirable proliferative effects on the tumour.

[Urinary bladder perforation caused by a loosened acetabular reinforcement ring]

Reinforcement cages are widely used for the treatment of large acetabular bone defects. We report the case of a loosened Burch-Schneider reinforcement ring causing a recurrent macrohaematuria due to a perforation of the urinary bladder. After performing several diagnostic procedures, the patient underwent interdisciplinary revision surgery. Due to the severe destruction of the acetabular bone stock and an infection of the total hip prosthesis as confirmed by fresh frozen section, the hip prosthesis was explanted. At the last follow-up the patient was free of infect-related symptoms and was able to walk with one crutch.

[Incidence of anterior intertrochanteric ossifications after total hip arthroplasty--a retrospective long-term follow-up study]

AIM

This retrospective study investigates the incidence of anterior intertrochanteric ossifications (AIO), especially in comparison with heterotopic ossifications classified according to Brooker. A classification system of AIO regarding short-term results (< 1 year after surgery) was introduced in 2003: AIO occurred solely in 13 % of all cases (ossifications according to Brooker grade 0) and would have been "overlooked" without a lateral X-ray. The incidence of AIO combined with ossifications according to Brooker > 0 was 48.8 % of all cases. Our study reports long-term results, furthermore correlations between ossifications and clinical outcome, rated by the Harris hip score (HHS) and range of motion (ROM), are evaluated.

MATERIAL AND METHODS

149 cementless total hip arthroplasties (Hofer-Imhof threaded cup, straight stem), implanted into 140 patients from November 1991 to December 1994 underwent complete clinical and radiological follow-up from December 2005 to October 2006. The average age of the 81 female and 59 male patients at the time of implantation was 64 years. Without exception, a conventional, transgluteal approach (Bauer) was performed. All patients received indomethacin prophylaxis for 8 consecutive days after surgery. Current X-rays (a.-p. and lateral view) were evaluated in comparison with the former X-rays.

RESULTS

AIO were found in 77 cases (51.7 %), heterotopic ossifications corresponding to Brooker in 93 cases (62.4 %), a combination of AIO and Brooker in 58 cases (38.9 %) and solitary AIO in 19 cases (12.8 %). HHS and ROM were not significantly altered by ossifications.

CONCLUSION

Our long-term findings compare with the short-term results (indicating lack of new bone formation [heterotopic ossification] after more than one year after surgery, as previously described in the literature concerning ossifications according to Brooker) and verify the incidence rate of solitary AIO. Despite a minor correlation with clinical outcome, AIO could be considered as a possible indicator for predilection of heterotopic bone formation, especially if revision arthroplasty or THA of the contralateral side is needed.

[Congenital pseudoarthrosis of the clavicle in a boy with Prader-Willi's syndrome]

The authors present the case of a boy with congenital pseudoarthrosis of the right clavicle who met all clinical and auxologic criteria of Prader-Willi's syndrome. Poor cooperation due to mental retardation was the reason for the primary conservative treatment. During this, deformity of the middle clavicle progressed, but without development of subjective complaints and functional deficit. At his 16 years, this cosmetic defect became unacceptable for his parents and, later than it is usually recommended, resection of pseudoarthrosis with plate osteosynthesis and autologous spongioplasty was indicated. The sufficient skeletal maturation and size of both fragments allowed us to perform stable osteosynthesis with the use of a contoured reconstruction plate, without the risk of insufficient osteosynthesis or clavicle fracture after the removal of osteosynthetic material.

Overexpression of amyloid precursor protein reduces epsilon protein kinase C levels

Alzheimer's disease (AD) is characterized by extracellular deposits of amyloid beta peptide (Abeta), a peptide that is generated upon proteolytic cleavage of amyloid precursor protein (APP). The events leading to the development of AD and their sequence are not yet fully understood. Protein kinase C (PKC) has been suggested to have a significant role in controlling neuronal degeneration and in the aberrant signal transduction taking place in AD. Several studies document a deficit in PKC levels and activity in brains of AD patients when compared with those of normal controls. Such a decrease in PKC could have serious implications since certain PKC isozymes were shown to drive the APP proteolytic cleavage into a non-amyloidogenic pathway. Reduced levels of distinct PKC isozymes could thus contribute to driving APP processing toward an amyloidogenic pathway. The direct cause for the down-regulation of PKC in AD brains is still unknown. In that respect, we tested in this study whether APP may play a role in PKC reduction. We show in three different cell lines (CHO, COS and BOSC) that overexpression of APP leads to decreased PKC levels. This decrease was found to be specific for the epsilon PKC isozyme whereas the levels of delta, alpha and conventional PKC remained unchanged. Furthermore, we observed this decrease for both active, membrane-associated and inactive, cytosolic epsilon PKC. APP-driven decrease in epsilon PKC is most likely mediated by a factor in the culture medium, since transfer of medium from cultured cells overexpressing APP to naïve, non-overexpressing cells, has also led to the selective decrease in epsilon PKC levels. Taken together, our results suggest that APP expression levels may play a role in the decrease of epsilon PKC levels in AD brains and could thus affect the responsiveness of AD brain tissues to growth factors and neurotransmitters.

Development of a fluorescence-based assay for screening of modulators of human organic anion transporter 1B3 (OATP1B3)

The organic anion transporting protein 1B3 (OATP1B3), formerly termed OATP8, is responsible for uptake and subsequent elimination of multiple amphipathic drugs by the liver. In silico methods for the prediction of transport rates for drugs and drug-like molecules might provide an important tool in drug development. Most prediction methods however require a large training set of in vitro experimental data in order to yield reliable results. To obtain these data, we have developed a fluorescence-based assay that allows screening a relatively high number of substances for their transporter affinity. HEK293 cells overexpressing OATP1B3 (HEK-OATP8) [Y. Cui, J. Konig, D. Keppler, Vectorial transport by double-transfected cells expressing the human uptake transporter SLC21A8 and the apical export pump ABCC2, Mol. Pharmacol. 60 (2001) 934-943.] were tested for transport of Fluo-3. Fluo-3 uptake could be seen in a concentration-dependent manner. Uptake can be inhibited completely by the addition of the known OATP1B3-inhibitor rifampicin proving that Fluo-3 is transported by OATP1B3. To verify the suitability of the system to identify modulators of OATP1B3, we tested known substrates for competitively inhibiting the Fluo-3 transport by giving them simultaneously with a 2muM Fluo-3-solution to the cells. The transport of Fluo-3 was decreased by all test substrates in a concentration dependent manner.

PET Detection of Solitary Distant Skeletal Muscle Metastasis of Esophageal Adenocarcinoma

A 67-year-old man with progressive dysphagia was recently diagnosed with a gastroesophageal junction adenocarcinoma. Contrast-enhanced CT scans of the abdomen and pelvis reported a large GE junction tumor without evidence of metastatic disease. FDG positron emission tomography revealed intense tracer accumulation in the soft tissue mass at the GE junction consistent with the primary neoplasm. In addition, PET scan also identified a solitary focus of intense FDG accumulation at the musculotendinous junction of the right gluteus minimus muscle. Subsequent MRI demonstrated mild enhancement and could not differentiate between tumor versus inflammation. Needle biopsy was performed and confirmed metastatic esophageal adenocarcinoma. A case of skeletal muscle metastases from late-stage (IV) gastroesophageal adenocarcinoma was previously reported. However, a solitary metastasis to a distant skeletal muscle without evidence of other lymphatic and hematogenous metastasis is quite unusual. The case supports the previous report that PET is superior in detecting distant metastases for initial staging of esophageal carcinoma over CT.

Subcutaneous tumor of the lower eyelid: a potential manifestation of a Dirofilaria repens infection

PURPOSE

To report a case of Dirofilaria repens presenting as a subcutaneous tumor of the lower eyelid.

METHODS

Interventional case report.

RESULTS

A 29-year-old man of Greek origin without systemic symptoms presented with a 3-week history of a small painless mass localized in the medial part of the lower eyelid. There was no history of a preceding trauma, injury, or visual impairment; however, the patient had recently been on a holiday in Italy. The lesion persisted after systemic antibiotic treatment. Routine blood tests were normal and the efferent tear ducts were patent. Upon surgical intervention a yellowish, pea-sized cyst-like structure was found beneath the orbicularis muscle and removed in toto. Histologic examination revealed the presence of a wormlike structure with the characteristic features of a single adult Dirofilaria repens nematode.

CONCLUSIONS

Infection with the nematode Dirofilaria repens has to be considered in the differential diagnosis of malignant and benign tumors of subcutaneous periocular tissues in patients who traveled to endemic areas.

[Examination of gastric emptying rate by means of 13C-octanoic acid breath test. Methods of the test for adults and results of the investigation of healthy volunteers]

BACKGROUND

13C-octanoic acid breath test (13C-OABT) is a simple, safe and non-invasive technique for measuring gastric emptying. However, the method has not been standardized yet. Aim of the study was to work up, introduce and evaluate our own method of the 13C-OABT for adults.

METHODS AND RESULTS

Ten healthy volunteers entered the study (5 men, 5 women, mean age 32 years, 50 % Helicobacter pylori positive). Standard test meals (with 100 mg 13C-sodium octanoate) were used three times within 3 weeks. The same solid meal (1,178 kJ) for Tests 1 and 2 contained scrambled egg (+ 3 g oil), white bread (40 g), butter (10 g) and distilled water (200 ml). Semi-solid meal (1,020 kJ) for Test 3 contained milk pudding (200 g) and distilled water (200 ml). Duplicate breath samples were obtained before and every 15 minutes after eating the test meal during 255 minutes. Altogether 1,080 breath samples were analysed twice (isotope ratio mass spectrometry, AP2003 Analytical Precision, UK). To assess the half-life of elimination (t1/2 E), we modelled the process of elimination with the incomplete gamma-function, which has a convenient form for the empiric plotting of breath test data. Mean t1/2E was 136+/-10 minutes (Test 1), 134+/-14 (Test 2) and 123+/-16 minutes (Test 3). Clinical reproducibility of 13C-OABT in particular persons was 98.2% (18 breath samples series), 90.8 % (15 samples) and 87.1% (9 breath samples series). There was a significant correlation between Test 1 and Test 2 results (r=0.887, p<0.0001). Mean difference of duplicate breath sample analysis was 1.460 % (in 540 pairs), mean baseline one-day analysis difference was 0.0982 (99.9274% accuracy). In healthy volunteers, normal range of t1/2E is 110-160 minutes for solids and 91-155 minutes for semisolid test meal. Using our own computed mean time of intermediate metabolism of 13C-octanoic acid (76.5+/-7.5 minutes), gastric emptying half-time is 33.5-83.5 minutes for solids and 14.5-78.5 minutes for semisolid test meal in healthy volunteers.

CONCLUSIONS

The 13C-OABT is accurate non-invasive method for gastric emptying measurement.

[Diabetes and celiac disease]

Celiac sprue is permanent lifelong intolerance of gluten which in some sensitive individuals leads to an inflammation of various grades followed by atrophy of jejunum mucosa. Diagnosis of celiac sprue is based on proof of histopathological changes in jejunum mucosa as a result of presence of gluten in food. In recent years, serum endogenous myosin and tissue transglutaminase antibodies were used in a diagnostic algorithm. We distinguish active, silent, latent, and potential celiac sprue. Simultaneous incidence of type I diabetes mellitus and celiac sprue has been documented in a range of studies. Both diseases have common immunology and genetic characters. Prevalence of celiac sprue in patients with type I diabetes is several times higher compared to prevalence of this disease in the population. There is the prevalence of celiac sprue 3.6-5.1% in children with type I diabetes mellitus in the Czech Republic, silent form of the disease is the most frequent one. An effect of a strict gluten free diet on a metabolic control of diabetes has not been proved. It is necessary to assess (at least once per two years) actively and on regular basis endogenous myosin and/or tissue transglutaminase antibodies in patients with type I diabetes.

ARX mutations in X-linked lissencephaly with abnormal genitalia

X-linked lissencephaly with abnormal genitalia (XLAG) is a distinct form of lissencephaly associated with absent corpus callosum. Recently, forms of syndromic and nonspecific X-linked mental retardation have been found to be associated with mutations in the Aristaless-related homeobox gene ARX. The authors assessed ARX as a candidate gene for XLAG in a genetic analysis of neuronal migration disorders and found two different point mutations in two XLAG pedigrees affecting the homeodomain of the protein, confirming that ARX is a causative gene for XLAG.

[Polyethylene liner dislocation in Harris Galante acetabular components]

AIM

Dislocation and subsequent dissociation of the polyethylene liner as a result of failure of the acetabular locking mechanism is a potential source of failure in the Harris-Galante acetabular component. The purposes of this study are to present seven cases with a liner dislocation due to failure of the liner locking mechanism.

METHOD

Between March 1997 and December 2001, seven patients who had had a total hip arthroplasty presented with clinical and radiologic signs of liner dislocation and signs of polyethylene wear of the liner from a Harris Galante acetabular shell. In all cases the intraoperative findings showed evidence of failure of the liner locking mechanism and subsequent dislocation. The medical records, radiographs, operative notes and explanted retrieved components were reviewed.

RESULTS

The components had been in situ for an average of 5.3 years (range 1-9 years). Two components were first generation, five were second generation. The symptoms developed spontaneously in five patients, the other two patients described a minor trauma. Radiographs showed eccentric position of the head in all cases. All acetabular components showed an excellent stability intraoperatively, nevertheless we had to remove the well fixed acetabular shell due to complete destruction of the liner locking mechanism in two cases. Treatment consisted of revision of the shell in two patients and exchange of the liner in five patients. All retrieved liners showed severe deformation and/or fracture of the rim.

CONCLUSION

Harris Galante modular acetabular components have been used widely for primary and revision arthroplasty. The survival of this implant has been well documented in the literature. Failure of the liner locking mechanism and following dislocation or fracture of the polyethylene liner is a potential cause of failure which may possibly occur more often than the literature to date has documented. We report seven cases of liner dislocation, in which two acetabular components had to be removed completely due to destruction of the liner locking mechanism. In the other five cases exchange of the liner was possible thanks to well timed revision. We believe that, as the liner wears and becomes loose due to an inefficient locking mechanism, the load increases on the polyethylene rim until it deforms or fractures. As a consequence of the prosthetic design at that stage nothing can prevent the liner from rotating out of the shell.

[Anterior intertrochanteric ossification after total hip arthroplasty]

AIM

Heterotopic paraarticular ossifications are usually identified by an anterior-posterior radiograph of the corresponding hip and are consecutively classified by the well accepted methods of Brooker, Arcq or deLee. In these methods ossifications are solely evaluated by the means of a single a-p radiograph, hence a major part of ossifications located in the anterior intertrochanteric region cannot be evaluated. Our study deals with the incidence of ossifications exclusively verifiable by an axial radiograph.

METHOD

In the present study 209 patients' axial radiographs were retrospectively analysed by using our simple method of classification. In the axial projection these ossifications are situated anterior of the intertrochanteric region, therefore we created the term "anterior intertrochanteric ossification (AIO)". After developing a simple topographic scheme we classified these appearances by localisation and size.

RESULTS

After total hip arthroplasty by using the transgluteal approach ossifications situated in the anterior intertrochanteric region can develop. These ossifications appear as bone islands, shield or clip like (without fixed connection to the femoral cortical bone) or as solid exostoses. Due to their strict anterior localisation these formations are often solely verifiable by the means of an axial (Lauenstein) radiograph. We were able to identify anterior intertrochanteric ossifications (AIO) in 97 out of 209 patients (48.4 %), 27 patients (13 %) developing an anterior intertrochanteric ossification were classified grade 0 according to the methods of Brooker, Arcq and deLee.

CONCLUSION

According to the widely accepted methods of classification of paraarticular ossifications depending on a single a-p radiograph of the corresponding hip, 13 % of paraarticular ossifications would remain undocumented because of their strict anterior intertrochanteric position.

A molecular approach to the concerted action of kinases involved in energy homoeostasis

One of the most important duties of a cell is energy homoeostasis. Several kinases, including AMP-activated protein kinase (AMPK), creatine kinase and adenylate kinase, are involved in the immediate response to stress, resulting in energy depletion. Here, we present our view of events preceding the downstream processes mediated by AMPK and leading to reduced energy expenditure and increased energy production. Unfortunately, AMPK is very poorly defined at the molecular level. Thus a procedure for production of AMPK in milligram amounts is presented which will greatly facilitate the functional and structural characterization of this protein kinase.