A case of a giant mucocoele of the appendiceal stump presented with a palpable mass in the right thigh: pre-operative diagnosis based on characteristic multidetector CT findings

The pre-operative diagnosis of a mucocoele of the appendiceal stump (MAS) may be difficult owing to rarity and non-specific clinical presentation. However, a pre-operative diagnosis of a MAS is important to prevent widespread dissemination by inadvertent spillage of mucous contents. We describe a case of a MAS presenting with a palpable mass in the right thigh in which a pre-operative diagnosis was made by characteristic multidetector CT (MDCT) findings.

Association of coronary artery calcification with obstructive sleep apnea and obesity in middle-aged men

BACKGROUND AND AIMS

Obstructive sleep apnea (OSA) and obesity are closely associated, and both have been reported to increase the risk of coronary heart disease. Although obesity is known to be associated with coronary artery calcification (CAC), there is limited information on whether OSA is associated with CAC independent of obesity.

METHODS AND RESULTS

A cross-sectional study examined the association between OSA and CAC among 258 healthy men, ages 40-49 years old, randomly selected from a population-based cohort. All individuals underwent overnight polysomnography and electron-beam computed tomography to measure their apnea-hypopnea index (AHI) and degree of CAC. A logistic regression model including potential cardiovascular risk factors excluding body mass index (BMI) showed that the presence of CAC was significantly greater in the fourth quartile versus the first quartile of AHI severity (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.01-4.86). A multivariate linear regression model excluding BMI also showed that AHI was significantly associated with CAC (P = 0.004). However, this association was no longer significant after adjusting for BMI.

CONCLUSIONS

In our cross-sectional study, even though both OSA and obesity were positively associated with the presence and extent of CAC, only obesity remained a significant independent contributor after an adjustment for potential cardiovascular risk factors, irrespective of OSA.

Strychnine poisoning: gone but not forgotten

Strychnine was used as a pesticide until 1968 and a rodenticide until 2006 when its sale was banned throughout the EU and all supplies recalled. A case of strychnine poisoning seen in a UK emergency department in 2009 is reported to remind clinicians of the features and management of this increasingly rare presentation. Prompt recognition and early intensive supportive therapy can result in a favourable outcome.

Management of anticoagulation following central nervous system hemorrhage in patients with high thromboembolic risk

SUMMARY BACKGROUND

Patients who present with central nervous system (CNS) hemorrhage while on anticoagulation (AC) for thromboembolic (TE) risk factors are a challenge to manage.

OBJECTIVE

We sought to inform decisions surrounding the timing and intensity of AC resumption by performing a systematic review.

METHODS

Three reviewers screened publications from Medline and EMBASE and extracted data. Hemorrhagic and TE adverse events that occurred subsequent to the index hemorrhage were recorded, as was their timing relative to presentation and covariates that might influence their occurrence.

RESULTS

Data were extracted from 63 publications detailing 492 patients; 7.7% of patients experienced hemorrhagic complications and 6.1% experienced TE complications. Hemorrhagic complications were more common within 72 h of presentation while TE complications were more common thereafter. Patients restarted on AC after 72 h were significantly more likely to have a TE complication (P = 0.006) and those restarted before 72 h were more likely to hemorrhage (P = 0.0727). Factors associated with re-hemorrhage included younger age, traumatic cause, subdural hematomas and failure to reverse AC. TE complications were more common in younger patients and those with spinal hemorrhage, multiple hemorrhages, and non-traumatic causes of the index hemorrhage. Re-initiation of AC at a lower intensity also significantly increased the risk of TE complications.

INTERPRETATION

Our results suggest that it may be prudent to re-initiate AC earlier than previously thought, with the timing and intensity modified based on predictors of TE and hemorrhagic complications. These findings must be explored in a prospective study because of limitations inherent to the analyzed studies.

The identification of prostaglandins E(2), F(2alpha) and A(2) from rabbit kidney medulla

Rabbit kidney medulla (10kg.) was homogenized in 5mm-disodium hydrogen phosphate and deproteinized with ethanol, and the concentrated supernatant solution was extracted at pH8 with light petroleum and at pH2 with chloroform. The acidic lipids present in the chloroform phase were separated on silicic acid columns into three biologically active fractions. The first fraction contained only vasodepressor activity; the second fraction contained both vasodepressor and non-vascular-smooth-muscle-stimulating activity; the third fraction contained both vasopressor and non-vascular-smooth-muscle-stimulating activity. Purification of each fraction by reversed-phase partition and thick-layer chromatography yielded three pure acids. Thin-layer chromatographic, spectroscopic and mass-spectral analysis of the acids and their methyl esters established their structures as prostaglandins E(2), F(2alpha) and A(2). Evidence is presented demonstrating that part or all of the prostaglandin A(2) is formed during the isolation procedures from endogenous prostaglandin E(2).

Pre-Measured Length Using Landmarks on Posteroanterior Chest Radiographs for Placement of the Tip of a Central Venous Catheter in the Superior Vena Cava

Central venous catheterization (CVC) is a common procedure but catheter misplacement is a frequent complication and can be lethal. Most CVCs are inserted at a recommended mean depth of 15 cm from the skin puncture site. Chest radiographs are used to confirm the positioning of CVCs, with the carina regarded as a reliable landmark for tip placement. The C-length, defined as the distance from the edge of the right transverse process of the first thoracic spine to the carina, can be measured on posteroanterior chest radiographs. To test the accuracy of C-length based CVC placement, 637 adult patients scheduled to undergo elective major abdominal procedures and neurological surgical procedures requiring CVC were randomized to undergo either the 15-cm guided method or the C-length guided method for placement of the CVC tip into the superior vena cava (SVC). All the CVC tips in the C-length group were successfully placed in the SVC. These findings indicate that the pre-measured C-length using two landmarks can be used to determine the insertion length and to place the CVC tip successfully into the SVC.

Dapsone hypersensitivity syndrome with circulating 190-kDa and 230-kDa autoantibodies

Dapsone has potent anti-inflammatory effects, and is used in the treatment of leprosy, cutaneous vasculitis, neutrophilic dermatoses, and dermatitis herpetiformis and other blistering disorders. However, it may cause severe adverse reactions such as hypersensitivity syndrome, which is characterized by fever, skin rash, hepatitis and lymphadenopathy. We report a 44-year-old female Korean patient with dapsone hypersensitivity syndrome (DHS) that presented as a bullous skin eruption. The patient had a 1-year history of urticarial vasculitis, treated with antihistamines, prednisolone and dapsone. Although the skin lesions improved, she reported fever, nausea, abdominal pain, jaundice, fatigue and skin rashes. On physical examination, there were generalized erythematous macules and purpura with facial oedema that developed into vesicles on the upper limbs. Histological examination of a skin biopsy of a vesicular lesion found subepidermal oedema with a mixed inflammatory cell infiltrate, including eosinophils in the dermis. Indirect immunofluorescence testing using normal foreskin as substrate revealed IgG deposits in the basement membrane zone. Circulating autoantibodies against antigens of 190 and 230 kDa were found by immunoblotting analysis using epidermal extracts. This case illustrates DHS with the formation of circulating autoantibodies.

Efficacy and safety of solifenacin succinate in Korean patients with overactive bladder: a randomised, prospective, double-blind, multicentre study

PURPOSE

We assessed the efficacy and safety of solifenacin compared with tolterodine for treatment of overactive bladder (OAB) in Korean patients.

MATERIALS AND METHODS

The study was randomised, double-blind, tolterodine-controlled trial in Korea. Patients had average frequency of >or= 8 voids per 24 h and episodes of urgency or urgency incontinence >or= 3 during 3-day voiding diary period. Patients were randomised to 12-week double-blind treatment with either tolterodine immediate release (IR) 2 mg twice daily (TOL4) or solifenacin 5 mg (SOL5) or 10 mg (SOL10) once daily. The outcome measure was mean change in daily micturition frequency, volume, daily frequency of urgency incontinence, urgency and nocturia from baseline to week 12. Quality of life was assessed using the King's Health Questionnaire.

RESULTS

A total of 357 were randomised and 329 were evaluated for efficacy. All voiding parameters recorded in micturition diary improved after treatment in all three groups. Mean changes in volume voided were 19.30 ml (26.69%) in TOL4, 30.37 ml (25.89%) in SOL5 and 37.12 ml (33.36%) in SOL10 group (p = 0.03). Speed of onset of SOL10 efficacy on urgency incontinence was faster than that of SOL5 and TOL4. Quality of life improved in all three groups. Dry mouth was the most common adverse event; its incidence was the lowest in SOL5 group (7.63%, compared with 19.49% and 18.64% in SOL10 and TOL4 groups respectively).

CONCLUSIONS

Solifenacin succinate 5 and 10 mg once daily improve OAB symptoms with acceptable tolerability levels compared with tolterodine IR 4 mg. Solifenacin 5 mg is a recommended starting dose in Korean patients with OAB.

Correlation between the in vitro ATP-based chemosensitivity assay and HER2/neu expression in women with breast cancer

Several in vitro chemosensitivity tests have been developed to predict the chemotherapeutic response of tumours prior to initiation of individualized treatment for breast cancer. This study investigated whether the in vitro chemosensitivity response of cell lines derived from breast cancer patients was affected by HER2/neu expression. We cultured breast cancer cell lines from 50 patients and the adenosine triphosphatebased chemotherapy response assay (ATPCRA) was performed with 5-fluorouracil, gemcitabine, docetaxel, doxorubicin, methotrexate, vinorelbine and paclitaxel. 5-fluorouracil combined a high median cell death rate (32.4%) with the narrowest range of cytotoxic effects (7.3-65.7%). In addition, gemcitabine showed significantly greater activity in HER2/neupositive patients. In contrast, docetaxel was significantly less effective in HER2/neu-positive patients. No significant correlation was found between the other agents and HER2/neu expression. The use of the ATP-CRA test for metastatic tissue from patients with recurrent disease might be a useful approach to determine the most effective chemotherapy regimen.

Osseointegration of anodized titanium implants under different current voltages: a rabbit study

The oxide layer that covers a titanium surface is extremely stable and appears to have excellent biocompatibility, which can result in successful osseointegration. The aim of this study was to analyse the characteristics of an oxide layer formed by anodic oxidation (anodization), and to evaluate the extent of bone healing around the anodized implant. The screw-type implants were made of commercially pure titanium (Grade 2). The Group 1 samples had a turned surface, and three other types of experimental specimens were anodized under constant voltages of 190 V (Group 2), 230 V (Group 3) and 270 V (Group 4). The surface characteristics of each sample type were inspected. Removal torque was measured after a 4-week healing period and the histomorphometric analysis was performed 6 weeks after implantation in rabbit tibiae. There was an increase in both the size and number of pores as the anodizing voltage increased. The Ra value of the Group 4 samples was higher than those in the Group 1 and 2 samples (P < 0.05). Group 3 showed a difference compared with Group 1 (P < 0.05). A thicker oxide layer, which contained crystalline (anatase) TiO(2) with the inclusion of some electrolytes (Ca, P), was formed at the higher anodizing voltage. Group 4 had higher removal torque values and percentages of bone-to-implant contact than the other groups (P < 0.05). The anodized titanium implants showed more intimate and stronger connections with peri-implant bone during early osseointegration than the turned titanium implants in this experimental model.

A giant malignant peripheral nerve sheath tumour of the breast: CT and pathological findings

Malignant peripheral nerve sheath tumour (MPNST) is a rare soft tissue sarcoma. In particular, primary MPNST of the breast is extremely rare. We report a case of a giant malignant peripheral nerve sheath tumour involving the entire right breast, which was not associated with neurofibromatosis type 1 (NF-1) or previous radiation therapy. A CT scan showed a huge heterogeneous soft tissue mass with well-enhanced nodules at its periphery and low-density internal necrosis, which was confirmed by modified radical mastectomy.

Photodetection of basal cell carcinoma using methyl 5-aminolaevulinate-induced protoporphyrin IX based on fluorescence image analysis

BACKGROUND

The preferential accumulation of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in neoplastic cells supports its potential use in the photodetection of porphyrin fluorescence in tumour cells. Hence, epithelial tumours, including basal cell carcinoma (BCC), might be visualized using the fluorescence of selectively accumulated ALA-induced PpIX.

AIM

In this study, we evaluated the clinical efficacy of PpIX fluorescence images using fluorescence image analysis (FIA) to define the lateral border between the tumour and tumour-free areas of facial BCC.

METHODS

FIA was used to define the lateral border between the tumour and tumour-free areas on red fluorescence images induced by the topical application of methyl 5-aminolaevulinate (MAL) ointment. According to the FIA results, 50 tissue samples, obtained from 10 patients with BCC, were divided into three categories: tumour area (n = 10), suspected tumour area (n = 20) and suspected tumour-free area (n = 20). These tissue samples were evaluated by histopathological examination. The FIA tool marked out the PpIX fluorescence image for defining the lateral border between the BCC tumour and tumour-free areas.

RESULTS

The rate of tumour detection from BCC lesions using PpIX fluorescence with the FIA tool showed a sensitivity of 94.1% and specificity of 82.6%.

CONCLUSION

These results suggest that MAL-induced PpIX fluorescence imaging using FIA is quite sensitive and specific for detecting tumour and occult tumour in facial BCC lesions. This method of presurgical in vivo imaging is therefore proposed as a useful tool for defining the lateral border between BCC tumour and tumour-free areas.

Paraneoplastic pemphigus without an underlying neoplasm

We describe a 52-year-old man with paraneoplastic pemphigus (PNP) without any evidence of an underlying neoplasm over an 8-year follow-up period. He had a chronic relapsing vesiculobullous eruption for approximately 7 years (from April 1998 to May 2005). Initially, scattered flaccid vesicles with crusts developed on the face and trunk, which waxed and waned several times. Our patient was diagnosed as having PNP based on immunopathological criteria for PNP, i.e. histopathological, immunoblotting and immunoprecipitation analyses. However, physical and laboratory examinations including serial blood tests with peripheral blood smear, whole-body positron emission tomography/computed tomography and abdominal ultrasound were unable to detect any underlying neoplasm over an 8-year follow-up period.

Biological responses of anodized titanium implants under different current voltages

The oxide layer of a titanium surface is very stable, and seems to result in excellent biocompatibility and successful osseointegration. The purpose of this study was to investigate the effects of high anodic oxidation voltages on the surface characteristics of titanium implants and the biologic response of rabbit tibiae. Bone tissue responses were evaluated by removal torque tests and histomorphometric analysis. Screw-shaped implants with microthreads were made of commercially pure titanium (Grade II). We prepared anodized implants under 300 V (group I), 400 V (group II), 500 V (group III) and 550 V (group IV). The surface characteristics of specimens were inspected according to three categories: surface morphology, surface roughness and oxide layer thickness. The screw-shaped implants were installed in rabbit tibiae. The removal torque values were measured and histomorphometric analysis was done after 1- and 3-month healing periods. Data indicate that as anodic oxidation voltage increased above 300 V, oxide layer thickness increased rapidly and pore size also increased. The roughness values of the implants increased with voltage up to 500 V, but decreased at 550 V. In the removal torque test, group III showed higher values than groups I and II at a statistically significant level (P < 0.05) after a 1-month healing period. In histomorphometric analysis, groups III and IV, after a 3-month healing period, showed greater bone to implant contact ratios for the total implant surface than did group I (P < 0.05).

Sera from patients with toxic epidermal necrolysis contain autoantibodies to periplakin

BACKGROUND

The pathophysiological mechanism of toxic epidermal necrolysis (TEN) with extensive bullae that is induced suddenly by drugs is not well understood. The individual patterns and distribution of the widespread mucocutaneous reactions of TEN often show striking similarities with those of paraneoplastic pemphigus (PNP), which is known to involve autoantibodies (aAbs) to members of the plakin family.

OBJECTIVES

To investigate the existence of circulating aAbs to periplakin in the sera of patients with TEN.

METHODS

The presence of circulating aAbs to periplakin was examined using immunoblotting, immunoabsorption and indirect immunofluorescence (IF) analyses. Recombinant protein expression was used to determine the interaction between periplakin and aAbs in the sera of patients with TEN.

RESULTS

Indirect IF studies revealed circulating aAbs in the intercellular area in the epidermis. Interestingly, on rat bladder the staining pattern of the IgG deposits was similar to that observed in patients with PNP. Immunoblotting analysis of the epidermal extracts was used to identify the aAbs in the sera of patients with TEN. These contained circulating aAbs to a 190-kDa protein corresponding to periplakin. Recombinant periplakin and domains of periplakin were prepared in order to confirm the existence of aAbs to periplakin. Immunoblotting with these proteins demonstrated that the sera from patients with TEN reacted with each domain as well as with the full-length periplakin.

CONCLUSIONS

We found that circulating aAbs in the sera of patients with TEN target periplakin. These aAbs might play a role in the pathogenesis of TEN as a humoral autoimmune mechanism.

Use of a forensic technique to identify blood contamination of emergency department and ambulance trauma equipment

Using a Kastle-Meyer (KM) technique, the following equipment from the emergency departments of six UK hospitals (four trusts) and three regional ambulance services was tested for blood contamination: extrication ("spinal") boards, cervical collars, straps, box splints, head blocks, and headboards. Only equipment ready for patient use was tested. Over half of trauma equipment (57%) tested positive for blood, including 15% of equipment that was visibly stained with blood. There have been no recorded cases of infection from contaminated trauma equipment but our study has identified the potential risk. Disposable covers for boards, disposable straps, and disposable radiolucent head blocks which are currently available provide a solution but have resource implications.

Detection of coins ingested by children using a handheld metal detector: a systematic review

To determine if the use of a handheld metal detector (HHMD) can safely reduce the number of radiographs requested in cases of coins ingested by children, a search was performed to identify prospective studies of the ability of an HHMD to identify the presence or absence of ingested coin in children (17 years or younger). Outcome measures were presence or absence of coin on metal detector screening, and accuracy of coin localisation. Inclusion and exclusion criteria were defined. Mantel-Haenszel (fixed effect model) pooling with 95% confidence intervals (CI) was used to calculate overall sensitivities and specificities. In total, 11 studies met the inclusion criteria. The overall sensitivity of the HHMD at detecting the presence of coins was 99.4% (95% CI 98.0 to 99.9%) and accuracy at localisation was 99.8% (98.5 to 100.0%). The overall specificity of the HHMD was 100% (76.8 to 100%). Use of the HHMD is an accurate, radiation free, and cost effective method of identifying and localising coins ingested by children. An algorithm for investigating children with coin ingestion is proposed.

Scoring and staging systems using cox linear regression modeling and recursive partitioning

OBJECTIVES

Scoring and staging systems are used to determine the order and class of data according to predictors. Systems used for medical data, such as the Child-Turcotte-Pugh scoring and staging systems for ordering and classifying patients with liver disease, are often derived strictly from physicians' experience and intuition. We construct objective and data-based scoring/staging systems using statistical methods.

METHODS

We consider Cox linear regression modeling and recursive partitioning techniques for censored survival data. In particular, to obtain a target number of stages we propose cross-validation and amalgamation algorithms. We also propose an algorithm for constructing scoring and staging systems by integrating local Cox linear regression models into recursive partitioning, so that we can retain the merits of both methods such as superior predictive accuracy, ease of use, and detection of interactions between predictors. The staging system construction algorithms are compared by cross-validation evaluation of real data.

RESULTS

The data-based cross-validation comparison shows that Cox linear regression modeling is somewhat better than recursive partitioning when there are only continuous predictors, while recursive partitioning is better when there are significant categorical predictors. The proposed local Cox linear recursive partitioning has better predictive accuracy than Cox linear modeling and simple recursive partitioning.

CONCLUSIONS

This study indicates that integrating local linear modeling into recursive partitioning can significantly improve prediction accuracy in constructing scoring and staging systems.

Conservative treatment for closed fifth (small finger) metacarpal neck fractures

BACKGROUND

Subcapital fractures of the fifth metacarpal bone, meaning fractures just below the knuckle of the little finger, account for approximately 20% of all hand fractures. Currently, there is no consensus concerning the optimal management of these fractures. Traditionally, treatment consists of closed reduction and external splinting in a neutral position using plaster of Paris (POP), involving the metacarpal joint, the proximal interphalangeal joint and the carpo-metacarpal joint. An alternative treatment strategy is functional treatment using taping or bracing that does not restrict movement.

OBJECTIVES

To compare functional treatment with immobilization, and to compare different periods and types of immobilization, for the treatment of closed fifth metacarpal neck fractures in adults.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialized Register (July 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 3, 2004), OVID OldMEDLINE (1951 to 1965), OVID MEDLINE (1966 to July 2004), OVID MEDLINE In-Process (July 2004), EMBASE (1988 to 2004, week 29), the Internet, and reference lists of articles. No language restrictions were applied.

SELECTION CRITERIA

All randomized and quasi-randomized controlled trials which compare functional treatment with immobilization or different types of immobilization for closed fifth metacarpal neck fractures.

DATA COLLECTION AND ANALYSIS

Two review authors assessed abstracts of all studies identified by the initial search, identified studies meeting the selection criteria, independently assessed the quality of the trial reports, and extracted and analysed the data.

MAIN RESULTS

Five studies met the inclusion criteria including a total of 252 participants. Most studies were of poor quality. The primary outcome measure, function of the hand, was not used in any studies. There was no evidence that any of the treatment modalities was statistically significantly superior.

AUTHORS' CONCLUSIONS

No included studies reported our primary outcome measure of interest, validated hand function. There was heterogeneity between the studies, which were of limited quality and size. No single non-operative treatment regimen for fracture of the neck of the fifth metacarpal can be recommended as superior to another in result. Further research is definitely warranted.

Head injuries in airbag-equipped motor vehicles with special emphasis on AIS 1 and 2 facial and loss of consciousness injuries

OBJECTIVES

Safety of the airbag supplemental restraint system (airbag) is a well-known concern. Although many lives are saved each year through airbag use, injuries continue to occur, especially to the head. Airbag safety research has focused primarily on severe injuries, while minor and moderate injuries have been largely ignored.

METHODS

In this study, 205,977 injury cases from the 1995 to 2001 National Automotive Sampling System (NASS)/ Crashworthiness Data System (CDS) were surveyed to determine the prevalence of AIS 1 and 2 facial and brain loss of consciousness (LOC) injuries and determine if these injuries are a concern. The query was focused on frontal impacts in vehicles equipped with airbags. Only occupants wearing appropriate seatbelts were included in this study so that the airbag would provide occupant protection under optimal conditions. Of the 205,977 injury cases studied, 2.4% met this criterion.

RESULTS

From the data gathered, the trends seem to indicate an increase in these specific injuries, both in terms of the total number and the proportion to all injury cases. In 1995, AIS 1 and 2 head injuries accounted for 96.5% of all head injuries caused by airbags. By 2001, the percentage had risen 3.0% to 99.5%. Injuries occurring in vehicles equipped with first-generation versus second generation airbags were compared, and data seem to suggest that there is a higher rate of minor and moderate head injuries when occupants are in second-generation airbag-equipped vehicles, even when appropriate lap and shoulder belts are used.

CONCLUSIONS

The short timeframe surveyed prevents drawing meaningful conclusions about statistical significance, but the graphical representations of the data in this study underscore an urgent need for further investigation based on current trends in order to understand the issue of minor and moderate head injury prevention in regard to airbags.

Strain-rate dependent material properties of the porcine and human kidney capsule

This study was performed to characterize the mechanical properties of the kidney capsular membrane at strain-rates associated with blunt abdominal trauma. Uniaxial quasi-static and dynamic tensile experiments were performed on fresh, unfrozen porcine and human renal capsules at deformation rates ranging from 0.0001 to 7 m/s (strain-rates of 0.005-250 s(-1)). Single stroke, dynamic tests were performed on samples of porcine renal capsule at strain-rates of 0.005 s(-1) (n = 33), 0.05 s(-1) (n = 17), 0.5 s(-1) (n = 38), 2 s(-1) (n = 10), 4 s(-1) (n = 10), 50 s(-1) (n = 21), 100 s(-1) (n = 18), 150 s(-1) (n = 17), 200 s(-1) (n = 10), and 250 s(-1) (n = 17). Due to limited availability of human tissues, only quasi-static tests were performed (0.005 s(-1), n = 25). Porcine renal capsule properties were found to match the material properties of human capsular tissue sufficiently well such that porcine tissue material can be used as a human test surrogate. The apparent elastic modulus and breaking stress of the porcine renal capsule were observed to increase significantly with increasing strain-rate (p < 0.01). Breaking strain was inversely related to strain-rate (p < 0.01). The effect of increasing strain-rate on material properties diminished appreciably at rates exceeding 150 s(-1). Empirically derived mathematical models of constitutive behavior were developed using a hyperelastic/viscoelastic Ogden formulation, as well as a Cowper-Symonds law material curve multiplication.

An abutment screw loosening study of a Diamond Like Carbon-coated CP titanium implant

The aim of this study was to quantify the extent of abutment screw loosening and thus understand the role of frictional and wear factors in abutment screw loosening by using a cyclic loading device to compare Diamond Like Carbon (DLC)-coated and non-coated implants. The properties of DLC films, including hardness, wear resistance, chemical stability, and biocompatibility, are similar to those of real diamond materials. In this study, a 1-mum thick DLC film served to protect and lubricate a layer of commercially-pure titanium affixed to the top of a dental implant (external hexagon-shaped implant). A cyclic loading force was then applied to the top of the prosthetic portion of the implants in order to determine the difference in looseness of the titanium abutment screw between ten DLC-coated implants and ten non-coated implants. The abutment screw loosening tests were performed with 100 N of force at a frequency of 20 Hz. Data indicate that implants with a DLC coating are more resistant to an applied force (P = 0.002) than are those without the coating. We hope these results will be useful for preventing implant abutment screw loosening.

Microencapsulated ascorbic acid for milk fortification

The present study was designed to develop a microencapsulated L-ascorbic acid and iron that could be used to fortify milk and to determine the sensory properties of milk fortified with microencapuslation. Coating material was medium-chain triacylglycerol (MCT), and selected core material was ferric ammonium sulfate and L-ascorbic acid. The highest efficiency of microencapsulation was 95.0% in the ratio of 15:1 as coating to core material. Ascorbic acid release was increased sharply up to 5 d storage as 6.5%. TBA value was the lowest when both capsulated iron and ascorbic acid were added during 12 d storage, compared with other treatments. In sensory analysis, most aspects were not significantly different between control and capsulated ascorbic acid fortified milk at 5 d storage. The present study indicated that the use of microencapsulated ascorbic acid with MCT is effective for fortifying milk. In addition, these results suggest that acceptable milk products can be prepared with microencapsulated ascorbic acid and iron.

Enhanced expression of transglutaminase 2 in anterior polar cataracts and its induction by TGF-beta in vitro

BACKGROUND/AIMS

Transglutaminase activity has long been implicated in the cataract formation. However, the precise mechanism of how it is produced and involved in this process remains unclear. Here the authors sought to examine whether transglutaminase 2 (TGase 2) is expressed in lens epithelial cells from patients with anterior polar cataracts, to determine whether TGase 2 expression is induced by transforming growth factor (TGF-beta) in cultured lens epithelial cells, and to determine whether TGase 2 participates in the crosslinking of fibronectin in lens epithelial cells in vitro.

METHODS

Lens epithelial cells from anterior polar cataracts, nuclear cataracts, and non-cataractous clear lenses were examined for the expression of TGase 2 using reverse transcription-polymerase chain reaction, western blot analysis, and immunohistochemical analysis. The modulation of extracellular TGase 2 activity by TGF-beta was measured by the formation of fibronectin polymers and the incorporation of fluorescein cadaverine into extracellular matrix proteins. The effect of TGase 2 overexpression was analysed by immunofluorescence staining and western blot analysis of human lens epithelial (HLE) B-3 cells transiently transfected with TGase 2 gene.

RESULTS

The expression of TGase 2 mRNA and its protein was markedly enhanced in lens epithelial cells from patients with anterior polar cataracts. Treatment of HLE B-3 cells with TGF-beta caused an increase in TGase 2 protein, its extracellular activity, and the crosslinking of fibronectin. Transient transfection of HLE B-3 cells with the TGase 2 gene led to the increased production of fibronectin monomers and polymers.

CONCLUSIONS

This study shows that TGase 2 is overexpressed in lens epithelial cells from anterior polar cataracts and that TGF-beta may be a causative factor in the induction of TGase 2. The enhanced expression of TGase 2 might cause the accumulation and crosslinking of the extracellular matrix proteins and might play a part in anterior polar cataract development.