Long-term cytological and histological outcomes in women managed with loop excision treatment under local anaesthetic for high-grade cervical intraepithelial neoplasia

OBJECTIVE

This study examines the impact of excision margin status after large loop excision of the transformation zone (LLETZ) under local anaesthetic for high-grade cervical intraepithelial neoplasia (HG-CIN) on the cytological and histological outcomes up to 5 years after treatment.

METHODS

  Prospective cytological and histological data were obtained by examination of the colposcopy database at Addenbrooke's Hospital, Cambridge, UK. All women aged between 19 and 50 years who underwent treatment for HG-CIN by LLETZ under local anaesthetic were included in the study. Patients without follow-up data were excluded from the study. The excision margin status was correlated with the subsequent cytological and histological outcomes.

RESULTS

A series of 967 women with CIN2 and CIN3 underwent LLETZ excision under local anaesthetic. Overall, 42% of women had disease present at the excision margin following LLETZ. Women with CIN3 were more likely than those with CIN2 to have an involved excision margin (P<0.0001). Cytological recurrence was highest at 12 months (16%) and did not correlate with the CIN grade or excision margin status. Histological recurrence/persistence was also highest at 12 months follow-up (15%) and this correlated with grade of CIN and margin status (P<0.0001).

CONCLUSIONS

Histological recurrence/persistence correlates with grade of CIN and excision margin status. Management of HG-CIN in an outpatient setting under local anaesthetic is safe, cost effective and yields a favourable long-term outcome.

Design of an Actuated Volume Compensating SLS Prosthetic Socket

Studies have shown residual limb volume can vary −11% to 7% in a single day due to changing activity level or weight. However, volume changes of only 3% to 5% can cause users to have difficulty putting on their prosthetic socket. Many existing volume compensation methods are cumbersome, rely on the amputee to maintain the appropriate pressure level, or allow only for a decrease in limb volume. Automatic compensation for volume gain and loss is therefore needed; however, the complexity of designing such sockets renders a traditional fabrication methods cost prohibitive or technically infeasible. Selective Laser Sintering (SLS), a rapid manufacturing (RM) technology, addresses both of these concerns. SLS is a layer-based RM technology that relies on a high power laser to fuse powder particles into a solid object. Minute detail, directly from a 3D CAD model, is possible and a technique has been established for manufacturing prosthetic sockets with passive compliant regions using SLS. Based on this SLS RM technique, steps toward developing a transtibial Nylon prosthetic socket that automatically adapts to volumetric changes in a residual limb will be described. A design methodology was developed to use RM including concept generation, refinement, and final verification. In concept generation, analogies, such as “Chinese Fingertraps” and balloons, were coupled with a review of socket designs in literature and industry and interviews with prosthetists. Inflation of a bladder integrated into the wall of a SLS socket is one of the promising design concepts generated, but the concept needs further refinement. In order to confidently design an inflatable SLS prosthetic, it is critical to understand the relationship between applied pressure and deflection. A testing specimen—5.08 cm diameter thinwalled membrane—was designed to simulate a bladder integrated into the wall of a SLS socket. Several thicknesses were also used to investigate the effects of this parameter on inflation. Preliminary tests were conducted using compressed air for quantifying pressure vs. displacement. During the tests, leakage through open porosity (due to low density) was detected. Density is strongly related to energy transmitted to the part during sintering. The energy concentration is quantified as the Andrew's Number (AN), the inverse relationship of laser power (LP) to laser scanning speed (SSP) and scan spacing (SS). Therefore, to determine the optimal AN—and therefore increase density—an experiment varying LP and SS (SSP is a manufacturer setting) to determine their effects on apparent density and tensile strength was completed. The optimal AN, 1.63 J/cm2 for Nylon 12 powder, was based on highest apparent density and tensile strength. Using this AN, additional deflection samples were tested. Initial results showed a maximum deflection of 2.1 mm at .145 MPa for a 1.3 mm thick membrane. In comparison, changing the volume of a 3D scan of a patient's residual limb by 6% in a 10.9 cm diameter region on the posterior distal tibia socket end, as recommended by a prosthetist, requires a 5.8 mm displacement. Therefore, early results suggest that a single bladder will not meet deflection requirements, influencing the design of multiple larger regions and use of a more flexible material. Results from these experiments will help eliminate concepts which cannot deflect the necessary amount for the volume change, further refining the concepts towards a solution.

Characterising the local immune responses in cervical intraepithelial neoplasia: a cross-sectional and longitudinal analysis

INTRODUCTION

Immunological competence influences the progression of cervical intraepithelial neoplasia (CIN) to invasive cancer. Information on the local immunological changes during the natural course of CIN is central for the development of new therapies.

OBJECTIVE

This study defines the populations of tissue-infiltrating immune cells in a cross-sectional cohort of different grades of CIN and also in a longitudinal cohort of regressing, persistent and progressing low-grade (LG)-CIN.

DESIGN

A cohort of 125 women with LG cytological atypia was recruited, of which 64/125 (51%) women with LG-CIN were followed prospectively for 1 year. Paraffin-embedded entry and exit cervical biopsies were used for immunohistochemistry analysis (CD4, CD8, CD56, FOXP3, CD1a and granzyme B).

RESULTS

At recruitment, 74/125 (59%), 39/125 (31%) and 12/125 (10%) women referred with LG smears had histologically proven LG-CIN, high-grade (HG) and normal biopsies, respectively. Seventeen of 64 (24.6%) women with LG-CIN progressed to HG-CIN within 1 year. In both LG-CIN and HG-CIN, the predominant intraepithelial cell population were cytotoxic T cells, while CD4+ and FOXP3+ T cells predominated the stromal compartment. Women with LG-CIN who later on regressed displayed a significantly higher number of cytotoxic (granzyme B+) cells in their entry samples. In addition, the ratio between CD8+ cells and granzyme B+ cells was close to 1, suggesting that all infiltrating CD8+ T cells were highly active. In contrast, this ratio was three-fold lower in women, in whom the lesions persisted or progressed.

CONCLUSIONS

This study suggests that the early infiltration of lesions by highly cytotoxic effector cells protects against progression.

Microbiology of infected arthroplasty: implications for empiric peri-operative antibiotics

PURPOSE

To classify the spectrum and antibiotic susceptibility of bacteria isolated from infected hip and knee arthroplasty specimens, and to recommend appropriate empiric peri-operative antibiotics.

METHODS

From January 1999 to August 2006, specimens from revision hip and knee arthroplasties (with or without suspected infection) were routinely collected for identifying possible organisms and their susceptibility patterns. During the period, 147 patients had positive specimens yielding 248 micro-organisms (from 195 tissue specimens, 43 fluid specimens, and 10 swabs). 140 isolates were from hips and 108 from knees.

RESULTS

Most isolates were Gram-positive; their distribution was similar in hip and knee specimens. Of the 248 micro-organisms isolated, Staphylococcus was the most common genus encountered (131, 53%), followed by Gram-negative isolates (24%). 88% of Gram-negative organisms were detected within 48 hours of inoculation and 94% of Gram-positive organisms within 96 hours. Overall, 46% of isolates were susceptible to cephalothin. Only 35% of coagulase-negative staphylococci were sensitive to cephalothin. No Gram-positive vancomycin resistance was encountered.

CONCLUSION

Empiric prophylactic antibiotics for revision hip and knee arthroplasties should include vancomycin to cover Gram-positive organisms and gentamicin for most Gram-negative bacteria.

In vitro reversal of the load-bearing properties of lipid-depleted articular cartilage following exposure to phospholipid surfactant solutions

BACKGROUND

A microscopic layer of surface active phospholipids overlays the articular cartilage of the knee. Its depletion in osteoarthritic joints results in loss of lubrication and load-bearing efficiency. We hypothesize that exposure of articular cartilage to the dominant unsaturated phospholipid component of knee surfactant can regenerate the load-bearing properties of the tissue. This was evaluated by studying the stress-strain and stiffness characteristics of normal intact and lipid-depleted cartilage exposed to lipid-based surfactants for known durations.

METHODS

Normal intact, lipid-depleted and surfactant-treated bovine articular cartilage specimens were compressed at 0.5mm/min to a maximum strain of 40% and their stress-strain and stiffness data were compared.

FINDINGS

The stiffness of lipid-depleted samples increased by 40% on average relative to the normal; after exposure of the same samples to saturated surfactant for one and 24h, the average stiffness decreased by 25% and 62%, respectively from this high value. On the other hand, exposure of delipidized specimens to a mixture of selected unsaturated surfactant species for one and 24h resulted in a reduction of 85% and 90% in the stiffness of the depilidized samples respectively, largely reversing the effect of lipid removal to a level much closer to that of the normal intact cartilage and therefore better than that obtained with incubation in the saturated surfactant.

INTERPRETATION

Lipid loss in articular cartilage results in a consistent increase in stiffness relative to normal tissue stiffness. This consequence of lipid loss can be partially reversed by the reintroduction of surface active phospholipids. The results of this study show that the lipid components of cartilage play an important role in determining the compliance of the loaded tissue.

Concurrent weekly cisplatin chemotherapy and radiotherapy in a haemodialysis patient with locally advanced cervix cancer

AIMS

Concurrent cisplatin chemo-radiotherapy improves outcome in cervical carcinoma. In haemodialysis patients, cisplatin is potentially hazardous. We report the treatment of a haemodialysis patient with cervix cancer using cisplatin-based chemo-radiation. Mathematical modelling using toxicity data from a range of cisplatin dosages and schedules reported in published studies was undertaken.

MATERIALS AND METHODS

The patient was treated using weekly cisplatin chemotherapy 25mg/m(2). The serum platinum levels were measured. Correlations between reported toxicity and platinum levels for a variety of cisplatin schedules in published studies were evaluated.

RESULTS

Treatment was completed with no interruptions and minimum acute toxicity. The platinum levels rose progressively. The elimination half-life was prolonged at 6.6-7.5 days. The percentage extraction varied between 7.7 and 41.0%. The cumulative cisplatin dose correlated with neurotoxicity (P=0.002). Myelotoxicity correlated with the peak cisplatin level in the first 15 days of treatment (P=0.01). With an elimination half-life of 7.5 days, 35 mg/m(2) weekly is predicted to have the same risk of myelotoxicity and neurotoxicity as 40 mg/m(2) weekly in a patient with normal renal function.

CONCLUSIONS

Weekly cisplatin chemotherapy 25mg/m(2) can be delivered safely in a haemodialysis patient. Dialysis is effective in eliminating platinum even if carried out more than 3h after infusion, but it should commence as soon as possible after cisplatin infusion, as the incidence of myelotoxicity is related to the peak platinum level.

Phosphorylation of vascular endothelial cadherin controls lymphocyte emigration

Lymphocytes emigrate from the circulation to target tissues through the microvascular endothelial cell (EC) barrier. During paracellular transmigration cell-cell junctions have been proposed to disengage and provide homophilic and heterophilic interaction surfaces in a zip-like process. However, it is not known whether ECs modulate junction proteins during this process. Here we show that tyrosine phosphorylation of adherens junction vascular endothelial cadherin (VEC) is required for successful transendothelial lymphocyte migration. We found that adhesion of lymphocytes or activation of the endothelial intercellular adhesion molecule 1 (ICAM1) led to tyrosine phosphorylation of VEC. Substitution of tyrosine for phenylalanine in VEC at positions 645, 731 or 733 produced ECs that were significantly less permissive to lymphocyte migration. We also found that these same tyrosine residues are involved in ICAM1-dependent changes of VEC phosphorylation. ICAM1 activation enhanced transendothelial permeability, suggesting the occurrence of junction disassembly. In agreement, the expression of VEC mutated at Y645F, Y731F or Y733F predominantly affected lymphocyte transmigration in paracellular areas. Taken together, these results demonstrate that phosphorylation of adherens junctions constitutes a molecular endpoint of lymphocyte-induced vascular EC signaling and may be exploited as a new target of anti-inflammatory therapies.

The influence of lipid-extraction method on the stiffness of articular cartilage

BACKGROUND

One of the known characteristics of osteoarthritis is the loss of articular cartilage lipids. Therefore, it is important to study how lipids influence the functions of the tissue. This can only be done successfully by indirect analysis involving the extraction of lipids and subsequent assessment of the delipidized matrix. Therefore, for accuracy, the procedure for lipid extraction must not induce any other modification in the samples to be assessed. Hence, we compare three rinsing agents and methods in this study.

METHODS

Normal and delipidized articular cartilage samples were tested under compressive loading at 4 loading velocities to obtain and compare their stiffness values.

FINDINGS

Chloroform rinsing resulted in a 45% decrease in the stiffness of cartilage at low strain-rates (10(-2)/s and 10(-1)/s) on average with a corresponding increase of 55% at higher strain-rate of 10/s relative to the normal. Ethanol rinsed cartilage exhibited a corresponding decrease of 40% at the low strain-rates while exhibiting an increase of about 20% at the highest loading rates. Propylene glycol rinsing resulted in a decrease of approximately 20% in stiffness, while an increase of up to 5% at high rates of loading.

INTERPRETATION

The loss of lipids modifies the stiffness of articular cartilage at all loading rates. The relatively larger deviation of the stiffness of chloroform-rinsed samples relative to the normal is probably a consequence of the drying process involved in rinsing protocol. It is probable that the results of milder rinsing agents, used without vacuum drying, are more reflective of physiological delipidization effects on the tissue. Consequently, we recommend propylene glycol and its associated protocol for extracting lipids from articular cartilage.

Genomic deletion marking an emerging subclone of Francisella tularensis subsp. holarctica in France and the Iberian Peninsula

Francisella tularensis subsp. holarctica is widely disseminated in North America and the boreal and temperate regions of the Eurasian continent. Comparative genomic analyses identified a 1.59-kb genomic deletion specific to F. tularensis subsp. holarctica isolates from Spain and France. Phylogenetic analysis of strains carrying this deletion by multiple-locus variable-number tandem repeat analysis showed that the strains comprise a highly related set of genotypes, implying that these strains were recently introduced or recently emerged by clonal expansion in France and the Iberian Peninsula.

Thermomechanical investigation of the cortical bone analogue in third-generation Sawbones femurs

The mechanical properties of the short glass fibre reinforced (SGFR) epoxy resin used as the cortical bone analogue in the third-generation Sawbones femurs were investigated for use within orthopaedic benchtop tests. Tensile and four-point bending tests were used to assess the material properties of the SGFR epoxy at both room (22 'C) and body temperatures (37 degrees C). The 20 standardized specimens used for the materials testing were machined from third-generation Sawbones femurs. The flexural properties of the specimens were determined using ASTM D6272-02 and the tensile properties were obtained using ASTM D638-02. The mean (and standard deviation, or SD) values of the modulus of elasticity in four-point bending for room and body temperature specimens of 7.8 (0.64) GPa and 2.8 (0.66) GPa respectively were significantly different (P < 0.001). The mean (and SD) values of the modulus of elasticity in tension for the room and body temperature specimens of 9.4 (0.8) GPa and 5.4 (1.3) GPa respectively were also significantly different (P = 0.02). The modulus of elasticity of SGFR epoxy is highly temperature dependent. A reduction in the modulus of elasticity of up to 63 per cent was observed when increasing the temperature of the specimens from room to body temperature. SGFR epoxy Sawbones do not accurately represent the material properties of bone at body temperature.

Description and validation of a rapid (1 h) flow cytometry test for enumerating thermophilic bacteria in milk powders

AIMS

The aim of this study was to develop a rapid assay for enumerating thermophilic bacteria in milk powder.

METHODS AND RESULTS

The BactiFlow flow cytometer was used to count bacteria based on esterase activity in viable bacterial cells. A protocol for total viable bacteria was modified by heat-treating the sample to selectively label thermophilic bacteria. Samples of milk powder dissolved in 0.1% peptone were treated with 0.8% ethylenediaminetetraacetic acid to reduce background interference because of denatured milk proteins. Either thermophilic bacteria were added to the dissolved milk powder or milk powder solutions were incubated at 55 degrees C for 2-3 h to enrich the natural thermophile population for testing. Results from the BactiFlow were compared with traditional plate count results.

CONCLUSIONS

Thermophilic bacteria in milk powder can be enumerated within 1 h using the BactiFlow flow cytometer.

SIGNIFICANCE AND IMPACT OF THE STUDY

Microbiological test results obtained within 1 h can potentially be used to monitor manufacturing processes, effectively trace problems and provide confidence in the manufacture of product.

The use of dynamic Lycra orthosis in the treatment of scoliosis: a case study

Treatment of scoliosis has been under discussion in relation to surgical intervention since the Boston brace was presented by Hall in 1976 (Hall et al. 1976; Watts et al. 1977). The effects of rigid bracing on thoracic skeletal integrity and the possible deformation of ribs due to the high localized pressure due to prolonged wear (Biorthex 1999; Coillard et al. 1999) have been highlighted. The lack of compliance (Houghton et al. 1987) has encouraged clinicians to investigate other options for non-surgical treatment. The Spinecor and Triac bracing systems have been developed as a result of this research; however, both of these orthoses had been designed with idiopathic scoliosis in mind. Little research has been done into the effects of bracing on the neuropathic curve. The use of dynamic Lycra garments in the treatment of neurological scoliosis offers the advantage of deformity correction without the bulk and discomfort of rigid braces. Recent clinical experience has shown that the Lycra suits have a positive effect in the treatment of scoliosis. This study discusses the treatment of a child presenting with a spinal tumour and although not truly of neurological presentation indicates that the garment can be used for the different scoliotic presentations.