No statistically significant kinematic difference found between a cruciate-retaining and posterior-stabilised Triathlon knee arthroplasty: a laboratory study involving eight cadavers examining soft-tissue laxity.

The aim of this study was to compare the maximum laxity conferred by the cruciate-retaining (CR) and posterior-stabilised (PS) Triathlon single-radius total knee arthroplasty (TKA) for anterior drawer, varus-valgus opening and rotation in eight cadaver knees through a defined arc of flexion (0º to 110º). The null hypothesis was that the limits of laxity of CR- and PS-TKAs are not significantly different. The investigation was undertaken in eight loaded cadaver knees undergoing subjective stress testing using a measurement rig. Firstly the native knee was tested prior to preparation for CR-TKA and subsequently for PS-TKA implantation. Surgical navigation was used to track maximal displacements/rotations at 0º, 30º, 60º, 90º and 110° of flexion. Mixed-effects modelling was used to define the behaviour of the TKAs. The laxity measured for the CR- and PS-TKAs revealed no statistically significant differences over the studied flexion arc for the two versions of TKA. Compared with the native knee both TKAs exhibited slightly increased anterior drawer and decreased varus-valgus and internal-external roational laxities. We believe further study is required to define the clinical states for which the additional constraint offered by a PS-TKA implant may be beneficial.

Clinical and post mortem analysis of combat neck injury used to inform a novel coverage of armour tool.

INTRODUCTION: There is a requirement in the Ministry of Defence for an objective method of comparing the area of coverage of different body armour designs for future applications. Existing comparisons derived from surface wound mapping are limited in that they can only demonstrate the skin entry wound location. The Coverage of Armour Tool (COAT) is a novel three-dimensional model capable of comparing the coverage provided by body armour designs, but limited information exists as to which anatomical structures require inclusion. The aim of this study was to assess the utility of COAT, in the assessment of neck protection, using clinically relevant injury data. METHOD: Hospital notes and post mortem records of all UK soldiers injured by an explosive fragment to the neck between 01 Jan 2006 and 31 December 2012 from Iraq and Afghanistan were analysed to determine which anatomical structures were responsible for death or functional disability at one year post injury. Using COAT a comparison of three ballistic neck collar designs was undertaken with reference to the percentage of these anatomical structures left exposed. RESULTS: 13/81 (16%) survivors demonstrated complications at one year, most commonly upper limb weakness from brachial plexus injury or a weak voice from laryngeal trauma. In 14/94 (15%) soldiers the neck wound was believed to have been the sole cause of death, primarily from carotid artery damage, spinal cord transection or rupture of the larynx. COAT objectively demonstrated that despite the larger OSPREY collar having almost double the surface area than the two-piece prototype collar, the percentage area of vulnerable cervical structures left exposed only reduced from 16.3% to 14.4%. DISCUSSION: COAT demonstrated its ability to objectively quantify the potential effectiveness of different body armour designs in providing coverage of vulnerable anatomical structures from different shot line orientations. To improve its utility, it is recommended that COAT be further developed to enable weapon and tissue specific information to be modelled, and that clinically significant injuries to other body regions are also incorporated.

Using computerised surface wound mapping to compare the potential medical effectiveness of Enhanced Protection Under Body Armour Combat Shirt collar designs.

INTRODUCTION: Protecting the neck from explosively propelled fragments has traditionally been achieved through a collar attached to the ballistic vest. An Enhanced Protection Under Body Armour Combat Shirt (EP-UBACS) collar has been identified as an additional method of providing neck protection but limited evidence as to its potential medical effectiveness exists to justify its procurement. METHOD: Entry wound locations and resultant medical outcomes were determined using Abbreviated Injury Scale (AIS) for all fragmentation neck wounds sustained by UK soldiers between 01 January 2010 and 31 December 2011. Data were prospectively entered into a novel computerised tool base and comparisons made between three EP-UBACS neck collar designs in terms of predicted reduction in AIS scores. RESULTS: All collars reduced AIS scores, with the greatest reduction provided by designs incorporating increased standoff from the neck and an additional semi-circle of ballistic material underneath the collar at the front and back. DISCUSSION: This technique confirms that reinforcing the neck collar of an EP-UBACS would be expected to reduce injury severity from neck wounds. However, without knowledge of entry wound locations for injuries to other body areas as well as the use of AIS scores without clinical or pathological verification its further use in the future may be limited. The ability to overlay any armour design onto a standardised human was potentially the most useful part of this tool and we would recommend developing this technique using underlying anatomical structures and not just the skin surface.

Clozapine--a dangerous drug in a clozapine-naïve subject.

Clozapine is a uniquely effective antipsychotic, but is very toxic in clozapine-naïve subjects. A 34-year-old male patient in a mental health facility, who was not prescribed clozapine, took 350 mg clozapine obtained from another patient at night. He was found dead the next morning. The presence of cardiomegaly related to obesity may have increased the risk of suffering an acute cardiac event after ingestion of clozapine. The medication prescribed to the patient was not thought to have contributed to the fatal outcome. Post mortem femoral blood clozapine and norclozapine concentrations were 0.48 and 0.20mg/L, respectively. By way of comparison, audit of 104,127 plasma samples (26,796 patients) assayed for therapeutic drug monitoring purposes 1993-2007, showed plasma clozapine 0.35 mg/L or more in 57.5% samples (8.4% 1mg/L or more). Those involved in the investigation of clozapine-associated deaths need to be aware that that death in an adult may occur after a single 'therapeutic' dose. A diagnosis of fatal clozapine poisoning cannot be made solely on the basis of a post mortem blood clozapine measurement.

Surface wound mapping of battlefield occulo-facial injury.

INTRODUCTION: Accurately determining the entry location of penetrating eye and face wounds and relating that to mortality and long-term morbidity is of vital importance in the design of future personal protective equipment. METHOD: Hospital and post mortem records for all UK servicemen sustaining penetrating battle injuries to the face or eye during the period 01 January 2005 to 31 December 2009 were analysed. RESULTS: Face and eye injuries were found in 391/1187 (33%) and 113/1187 (10%) of all battle-injured servicemen respectively. 27% of eye wounds from explosions resulted in blindness and a further 17% in significant permanently reduced visual acuity (<6/12). Those servicemen that chose not to wear Combat Eye Protection (CEP) were 36 times more likely to sustain an eye injury from explosive fragmentation than those that did. However only 36% of servicemen chose to wear CEP. 7 deaths could potentially have been prevented had the serviceman chosen to wear their CEP. The lower third of the face was most commonly injured (60%) followed by the upper third (24%). CEP reduced facial injuries as a whole (bone and soft tissue) by 15% (p<0.01). Potentially changing the existing material used for chinstrap and helmet covers to that with ballistic protection would further reduce this incidence by up to 9%. CONCLUSIONS: Although the lower third of the face remains poorly protected, the incidence of lower facial wounds could be further reduced by the use of ballistic visors by servicemen in exposed positions in vehicles (which represented 16% of facial injuries). Such a visor could potentially have prevented 17 deaths. A rigid attachment to the front of a ballistic helmet would allow either a visor, a high visibility LED lamp or a night vision goggle to clip in and we believe this capability should be investigated through future human factor trials.

Mandibular fractures in British military personnel secondary to blast trauma sustained in Iraq and Afghanistan.

Blast trauma is the primary cause of maxillofacial injury sustained by British service personnel on deployment, and the mandible is the maxillofacial structure most likely to be injured in combat, but there are few reports about the effect of blast trauma on it. The Joint Theatre Trauma Registry identified all mandibular fractures sustained by British servicemen secondary to blast injury between 1 January 2004 and 30 September 2009. These were matched to corresponding hospital notes from the Royal Centre for Defence Medicine (RCDM) for those evacuated servicemen and autopsy records for those who died of wounds. Seventy-four mandibular fractures were identified in 60 servicemen. Twenty-two soldiers were evacuated to the RCDM and the remaining 38 died from wounds. Fractures of the symphysis (39/106, 37%) and body (31/106, 29%) were more common than those of the angle (26/106, 25%) and condyle (10/106, 9%). This pattern of injury differs from that of civilian blunt trauma where the condyle is the site that is injured most often. Those fractures thought to result from the blast wave itself usually caused simple localised fractures, whereas those fractures thought to result from fragments of the blast caused comminution that affected several areas of the mandible. The pattern of fractures in personnel injured while they were inside a vehicle resembled that traditionally seen in blunt trauma, which supports the requirement for mandatory wearing of seat-belts in the rear of vehicles whenever tactically viable. All mandibular fractures in servicemen injured while in the turret of a vehicle had evidence of foreign bodies or radio-opaque fragments as a result of their exposed position. Many of these injuries could therefore be potentially prevented by the adoption of facial protection.

Encapsulation of fibroblasts causes accelerated alginate hydrogel degradation.

Calcium-alginate hydrogel has been widely studied as a material for cell encapsulation for tissue engineering. At present, the effect that cells have on the degradation of alginate hydrogel is largely unknown. We have shown that fibroblasts encapsulated at a density of 7.5 x 10(5) cells ml(-1) in both 2% and 5% w/v alginate remain viable for at least 60 days. Rheological analysis was used to study how the mechanical properties exhibited by alginate hydrogel changed during 28 days in vitro culture. Alginate degradation was shown to occur throughout the study but was greatest within the first 7 days of culture for all samples, which correlated with a sharp release of calcium ions from the construct. Fibroblasts were shown to increase the rate of degradation during the first 7 days when compared with acellular samples in both 2% and 5% w/v gels, but after 28 days both acellular and cell-encapsulating samples retained disc-shaped morphologies and gel-like spectra. The results demonstrate that although at an early stage cells influence the mechanical properties of encapsulating alginate, over a longer period of culture, the hydrogels retain sufficient mechanical integrity to exhibit gel-like properties. This allows sustained immobilization of the cells at the desired location in vivo where they can produce extracellular matrix and growth factors to expedite the healing process.

Subcellular localisation of cyclin B, Cdc2 and p21(WAF1/CIP1) in breast cancer. association with prognosis.

The heterodimeric cyclin B/Cdc2 protein kinase governs entry into mitosis, and can be negatively regulated through p53-mediated transcriptional induction of the cyclin-dependent kinase inhibitor p21(WAF1/CIP1). Ectopic expression of p21(WAF1/CIP1) in cultured cells has been shown previously to influence the subcellular distribution of the cyclin-dependent kinases (CDKs) including Cdc2. In this study, we have examined the subcellular localisation of Cdc2, cyclin B and p21(WAF1/CIP1) by immunohistochemistry in a well characterised series of primary breast cancers. Surprisingly, p21(WAF1/CIP1) was predominantly cytoplasmic in many of the tumours, where it was associated with high p53 levels; cytoplasmic p21(WAF1/CIP1) and high cyclin B levels were also significant predictors of poor prognosis. We conclude that breast tumorigenesis may be characterised by abnormalities in pathways determining not only levels of expression of key regulatory molecules, but also their subcellular localisation. Investigation of the subcellular distribution of cell cycle regulatory proteins, particularly p21(WAF1/CIP1), could provide valuable prognostic markers in breast cancer.

Cellular mechanisms of bone resorption in breast carcinoma.

The cellular mechanisms that account for the increase in osteoclast numbers and bone resorption in skeletal breast cancer metastasis are unclear. Osteoclasts are marrow-derived cells which form by fusion of mononuclear phagocyte precursors that circulate in the monocyte fraction. In this study we have determined whether circulating osteoclast precursors are increased in number or have an increased sensitivity to humoral factors for osteoclastogenesis in breast cancer patients with skeletal metastases (+/- hypercalcaemia) compared to patients with primary breast cancer and age-matched normal controls. Monocytes were isolated and cocultured with UMR 106 osteoblastic cells in the presence of 1,25 dihydroxyvitamin D3[1,25(OH)2D3] and human macrophage colony stimulating factor (M-CSF) on coverslips and dentine slices. Limiting dilution experiments showed that there was no increase in the number of circulating osteoclast precursors in breast cancer patients with skeletal metastases (+/- hypercalcaemia) compared to controls. Osteoclast precursors in these patients also did not exhibit increased sensitivity to 1,25(OH)2D3or M-CSF in terms of osteoclast formation. The addition of parathyroid hormone-related protein and interleukin-6 did not increase osteoclast formation. The addition of the supernatant of cultured breast cancer cell lines (MCF-7 and MDA-MB-435), however, significantly increased monocyte-osteoclast formation in a dose-dependent fashion. These results indicate that the increase in osteoclast formation in breast cancer is not due to an increase in the number/nature of circulating osteoclast precursors. They also suggest that tumour cells promote osteoclast formation in the bone microenvironment by secreting soluble osteoclastogenic factor(s).

New case of Beemer-Langer syndrome.

We present the case of a male infant born at 37 weeks gestation with multiple congenital anomalies, including hydrops fetalis, facial and visceral abnormalities, short ribs, and short limbs without polydactyly. We believe that this represents a further case of the Beemer-Langer syndrome, a relatively recently described form of lethal osteochondrodysplasia with an autosomal recessive mode of inheritance. This case also showed some less frequently described anomalies, including arachnoid cysts of the brain and short intestines.

Macrophage infiltration is associated with VEGF and EGFR expression in breast cancer.

Angiogenesis is esential for tumour growth and metastasis. Vascular endothelial growth factor (VEGF) is a potent endothelial cell mitogen and is an important component of the angiogenic stimulus in a range of human neoplasias. In addition to its mitogenic activities, VEGF has also been found to stimulate migration in macrophages via the flt-1 VEGF receptor. It has previously been shown that increased focal tumour macrophage infiltration is associated with increased angiogenesis and worsened relapse-free and overall survival in breast cancer. Macrophages are able to stimulate angiogenesis by their production of a range of factors including VEGF, tumour necrosis factor-alpha (TNF-alpha), and thymidine phosphorylase (TP). Thus, in breast cancer, VEGF could have a dual role in the regulation of angiogenesis, by direct mitogenic stimulation of endothelial cells, and also indirectly by attracting macrophages into avascular tumours. The purpose of this study was to localize VEGF protein in a series of 96 consecutive primary breast carcinomas and to determine its relationship to focal macrophage infiltration (macrophage index). These two variables were also compared with the pathological features of the tumours, as well as oestrogen receptor (ER), epidermal growth factor receptor (EGFR), microvessel density, macrophage index, and survival. An inverse relationship (p=0.0006) was noted between VEGF and EGFR, with high VEGF expression correlating with low EGFR levels. In the EGFR-negative group of cases (n=56), positive associations were observed between VEGF expression and macrophage index (p=0.005), ER (p=0.05), p53 (p=0. 006), tumour grade (p=0.02), and tumour necrosis (p=0.03). Macrophage counts were higher in EGFR-positive tumours (p=0.0006) and no associations were found between VEGF expression and increased microvessel density. These results show that in breast cancers there are two types of macrophage infiltrates, one associated with the presence of EGFR and low VEGF expression in tumours and the other with high VEGF expression in EGFR-negative tumours. VEGF expression may be an important factor in the recruitment of tumour-associated macrophages into breast carcinomas and may thus have an additional, indirect, pathway of angiogenic stimulation in this type of tumour.

Heat shock cognate 70 mutations in sporadic breast carcinoma.

Heat Shock Cognate 70 (HSC70) is a constitutively expressed molecular chaperone, functions of which regulate the structure, subcellular localization, and turnover of cell proteins. It is also a component of the centrosome facilitating rearrangements during mitotic/meiotic spindle formation and cytoplasmic microtubule organization. We localized HSC70 to 11q23.3, a region deleted in 40% of sporadic breast and other cancers. Sequencing demonstrated mutation in the NH2-terminal ATPase domain of HSC70 in 2 of 15 sporadic breast carcinomas examined. In both cases, mutation was coincident with allelic imbalance, suggesting that HSC70 is a target of somatic mutation and deletion in a fraction of breast carcinomas.

11q23.1 and 11q25-qter YACs suppress tumour growth in vivo.

Frequent allelic deletion at chromosome 11q22-q23.1 has been described in breast cancer and a number of other malignancies, suggesting putative tumour suppressor gene(s) within the approximately 8 Mb deleted region. In addition, we recently described another locus, at the 11q25-qter region, frequently deleted in breast cancer, suggesting additional tumour suppressor gene(s) in this approximately 2 Mb deleted region. An 11q YAC contig was accessed and three YACs, one containing the candidate gene ATM at 11q23.1, and two contiguous YACs (overlapping for approximately 400-600 kb) overlying most of the 11q25 deleted region, were retrofitted with a G418 resistance marker and transfected into murine A9 fibrosarcoma cells. Selected A9 transfectant clones (and control untransfected and 'irrelevant' alphoid YAC transfectant A9 clones) were assayed for in vivo tumorigenicity in athymic female Balb c-nu/nu mice. All the 11q YAC transfectant clones demonstrated significant tumour suppression compared to the control untransfected and 'irrelevant' YAC transfected A9 cells. These results define two discrete tumour suppressor loci on chromosome 11q by functional complementation, one to a approximately 1.2 Mb region on 11q23.1 (containing the ATM locus) and another to a approximately 400-600 kb subterminal region on 11q25-qter.

Fibrochondrogenesis in a 17-week fetus: a case expanding the phenotype.

Fibrochondrogenesis is a very rare form of lethal short-limb dwarfism, with 8 cases described since it was first reported in 1978. It is becoming clear that this condition has certain radiological and histological characteristics that distinguish it from other skeletal dysplasias. We herein present a further case of fibrochondrogenesis diagnosed in a fetus of 17 weeks, which is the youngest patient reported so far. In addition, the fetus showed severe micrognathia and a bifid tongue. These are not previously described manifestations, which extend the phenotype of this rare condition.

Loss of E-cadherin expression associated with lymph node metastases in small breast carcinomas.

The National Breast Screening Programme affords the opportunity to study breast carcinomas at an early stage in their development. E-cadherin is a calcium-dependent, intercellular adhesion molecule whose loss of expression may facilitate the processes of invasion and metastasis of some human tumours. From a group of screen-detected ductal carcinomas less than or equal to 10 mm in diameter, 16 with lymph node metastasis were identified and matched for grade, size and patient age with node negative tumours. The level of expression of E-cadherin (detected by immunocytochemistry) was compared in the matched pairs using a simple semi-quantitative intensity distribution scoring system. The results showed a significant (P = 0.05 Wilcoxon paired rank test) reduction of E-cadherin expression in tumours with lymph node metastases compared to those without. In the context of the small size of these tumours it is proposed that these results support the hypothesis that reduction in E-cadherin expression is an early event in the development of metastases.

The still video camera: a suitable and convenient method of demonstrating post mortem findings.

The post mortem demonstration continues to play an important role in medical education at both undergraduate and postgraduate levels. However, for a variety of reasons its format needs to be adaptable in order to maximize the educational benefit and increasingly to comply with legislation. We have developed a method of demonstration based upon a still video camera system which we have found is acceptable to our students and overcomes some of the problems associated with other formats. In this paper we describe the system itself, compare it with other systems, discuss its potential applications and present the results of a questionnaire-based survey of the first groups of medical students to be taught in this way. These results confirm that the technique is popular with students and that it appears to be a useful teaching modality worthy of further development.

High temperature antigen retrieval and loss of nuclear morphology: a comparison of microwave and autoclave techniques.

The use of high temperature antigen retrieval methods has been of major importance in increasing the diagnostic utility of immunocytochemistry. However, these techniques are not without their problems and in this report attention is drawn to a loss of nuclear morphological detail, including mitotic figures, following microwave antigen retrieval. This was not seen with an equivalent autoclave technique. This phenomenon was quantified using image analysis in a group of B cell lymphomas stained with the antibody L26. Loss of nuclear morphological detail may lead to difficulty in identifying cells accurately, which is important in the diagnostic setting-for example, when trying to distinguish a malignant lymphoid infiltrate within a mixed cell population. In such cases it would clearly be wise to consider the use of alternative high temperature retrieval methods and accept their slightly lower staining enhancement capability compared with the microwave technique.

Apoptotic bodies in a murine model of alcoholic liver disease: reversibility of ethanol-induced changes.

The aim of this study was to investigate the effects of ethanol exposure on the location and number of apoptotic bodies in murine liver. Livers from 21 control mice were compared with those of 41 animals exposed to ethanol vapour by inhalation for up to 23 days. In the control livers, apoptotic bodies were identified in association with 36 per cent of the terminal hepatic venules examined and 88 per cent of these bodies were located in the first two rows of perivenular hepatocytes. By comparison, in the ethanol-exposed group, apoptotic bodies were observed in association with 72 per cent of the terminal hepatic venules examined and more were found further from them. This increase in the number of apoptotic bodies was shown to depend on the duration of ethanol exposure and, furthermore, the effects of ethanol were shown to be completely reversed by a period of abstinence. These results indicate that ethanol exposure has time-dependent, reversible effects on both the location and the number of apoptotic bodies in murine liver. This extends knowledge gained from previous work on rat livers.

Nitric oxide production by monocytes in alcoholic liver disease.

Nitric oxide, initially described as an endothelial-derived relaxing factor, has recently been recognised as a mediator of macrophage function. We have studied the production of nitric oxide by peripheral blood monocytes from both normal volunteers and alcoholics. This was measured indirectly by assessing nitrite formation. Normal monocytes were found to produce a basal level of nitrite, which could be stimulated more than 6-fold using endotoxin. This effect was abrogated by the addition of nitric oxide synthesis inhibitor, L-n-monomethyl-arginine. A striking difference was observed in the monocytes obtained from alcoholics with and without evidence of alcoholic hepatitis. Whereas the latter behaved in a similar manner to the controls, the former had markedly increased basal levels. In the hepatitis group there was also substantial inhibition of production by L-n-monomethyl-arginine. We believe that these results indicate that nitric oxide derived from monocytes may play a role in the pathogenesis of alcoholic liver disease, especially alcoholic hepatitis.