Acquisition and retention of military surgical competencies: a survey of surgeons' experiences in the UK Defence Medical Services.

INTRODUCTION: The acquisition and retention of militarily relevant surgical knowledge and skills are vital to enable expert management of combat casualties on operations. Opportunities for skill sustainment have reduced due to the cessation of combat operations in Iraq and Afghanistan and lack of military-relevant trauma in UK civilian practice. METHODS: A voluntary, anonymous online survey study was sent to all UK Defence Medical Services (DMS) surgical consultants and higher surgical trainees in Trauma and Orthopaedics, Plastic and Reconstructive, and General and Vascular surgical specialties (three largest surgical specialties in the DMS in terms of numbers). The online questionnaire tool included 20 questions using multiple choice and free text to assess respondents' subjective feelings of preparedness for deployment as surgeons for trauma patients. RESULTS: There were 71 of 108 (66%) responses. Sixty-four (90%) respondents were regular armed forces, and 46 (65%) worked in a Major Trauma Centre (MTC). Thirty-three (47%) had never deployed on operations in a surgical role. Nineteen (27%) felt they had sufficient exposure to penetrating trauma. When asked 'How well do you feel your training and clinical practice prepares you for a surgical deployment?' on a scale of 1-10, trainees scored significantly lower than consultants (6 (IQR 4-7) vs 8 (IQR 7-9), respectively; p<0.001). There was no significant difference in scores between regular and reservists, or between those working at an MTC versus non-MTC. Respondents suggested high-volume trauma training and overseas trauma centre fellowships, simulation, cadaveric and live-tissue training would help their preparedness. CONCLUSIONS: There was a feeling among a sample of UK DMS consultants and trainees that better preparedness is required for them to deploy confidently as a surgeon for combat casualties. The responses suggest that UK DMS surgical training requires urgent attention if current surgeons are to be ready for their role on deployed operations.

Secure app-based secondary healthcare clinical decision support to deployed forces in the UK Defence Medical Services.

BACKGROUND: Modern instant messaging systems facilitate reach-back medical support for Defence Medical Services (DMS) by connecting deployed clinicians to remote specialists. The mobile app Pando (Forward Clinical, UK) has been used for this purpose by the DMS via the 'Ask Advice' function. We aimed to investigate the usage statistics for this technology in its first 1000 days to better understand its role in the DMS. METHODS: An observational study was undertaken using metadata extracted from the prospective database within the application server for clinical queries between June 2019 and February 2022. These data included details regarding number and name of specialties, timings, active users per day and the number of conversations. RESULTS: There were 29 specialties, with 298 specialist users and 553 requests for advice. The highest volume of requests were for trauma and orthopaedics (n=116; 21.0%), ear, nose and throat (n=67; 12.1%) and dermatology (n=50; 9.0%). There was a median of 164 (IQR 82-257) users logged in per day (range 2-697). The number of requests during each day correlated with the number of users on that day (r=0.221 (95% CI 0.159 to 0.281); p<0.001). There were more daily users on weekdays than weekends (215 (IQR 123-277) vs 88 (IQR 58-121), respectively; p<0.001). For the top 10 specialties, the median first response time was 9 (IQR 3-42) min and the median time to resolution was 105 (IQR 21-1086) min. CONCLUSION: In the first 1000 days of secure app-based reach-back by the DMS there have been over 500 conversations, responded to within minutes by multiple specialists. This represents a maturing reach-back capability that may enhance the force multiplying effect of defence healthcare while minimising the deployed 'medical footprint'. Further discussions should address how this technology can be used to provide appropriately responsive clinical advice within DMS consultant job-planned time.

A retrospective study into the levels of evidence presented at the Combined Services Orthopaedic Society annual meeting.

OBJECTIVES: The role of Evidence Based Medicine in clinical care is to provide a framework for the integration of expertise, current evidence and the needs of the individual patient. Research presented at scientific meetings is an important source of such evidence, informing clinical decision making both on military operations and in home nation health care systems. The aim of this study is to review the levels of evidence presented at the Combined Services Orthopaedic Society (CSOS) and two other related scientific meetings. METHODS: Retrospective review of abstracts presented at the annual scientific meetings of the CSOS, Society of Military Orthopaedic Surgeons (SOMOS) and the British Trauma Society (BTS). Basic science studies, animal studies, cadaveric studies, surveys and guest lectures were excluded. Research abstracts were categorised according to the Centre for Evidence-Based Medicine's (CEBM) hierarchy of evidence. Statistical comparison was performed to investigate differences in evidence levels presented at each scientific meeting and between each year of the CSOS meeting. RESULTS: 596 abstracts met the inclusion criteria for this study (179 CSOS, 173 SOMOS, 244 BTS). Level IV evidence accounted for the majority of presented abstracts at each meeting (72.6% CSOS, 69.4% SOMOS, 68.9% BTS). Level I evidence was uncommon at each meeting (6.1% CSOS, 5.2% SOMOS, 2.9% BTS). There was no statistical difference in the evidence levels presented at the three scientific meetings. CONCLUSIONS: The proportion of comparative clinical studies (Levels I-III) presented at military or trauma societies' scientific meetings reflects the difficulty of performing research in emergency surgery. This is further exacerbated in the military environment where operational commitments and delivery of care take priority. However, the future value of comparative clinical research in battlefield healthcare could have an enduring legacy that shapes trauma care for many decades.

Improvised skeletal traction in the management of ballistic femoral fractures.

Penetrating limb injuries are common during conflict, and in many there will be an associated fracture. Treatment of ballistic femoral fractures would usually be with by intramedullary nail; however, within the resource-constrained environment during conflict this is rarely possible. This report illustrates what can be achieved at a Role 2 facility to provide skeletal traction with the equipment and skills available. We discuss the history of skeletal traction and its use in ballistic femoral fractures, and believe that skeletal traction is still a valuable technique that we shouldn't ignore. Military surgeons should be able to use skeletal traction to manage ballistic femoral fractures in the spartan environment of a deployed forward hospital.

Outcomes following limb salvage after combat hindfoot injury are inferior to delayed amputation at five years.

OBJECTIVES: The surgical challenge with severe hindfoot injuries is one of technical feasibility, and whether the limb can be salvaged. There is an additional question of whether these injuries should be managed with limb salvage, or whether patients would achieve a greater quality of life with a transtibial amputation. This study aims to measure functional outcomes in military patients sustaining hindfoot fractures, and identify injury features associated with poor function. METHODS: Follow-up was attempted in all United Kingdom military casualties sustaining hindfoot fractures. All respondents underwent short-form (SF)-12 scoring; those retaining their limb also completed the American Academy of Orthopaedic Surgeons Foot and Ankle (AAOS F&A) outcomes questionnaire. A multivariate regression analysis identified injury features associated with poor functional recovery. RESULTS: In 12 years of conflict, 114 patients sustained 134 fractures. Follow-up consisted of 90 fractures (90/134, 67%), at a median of five years (interquartile range (IQR) 52 to 80 months).The median Short-Form 12 physical component score (PCS) of 62 individuals retaining their limb was 45 (IQR 36 to 53), significantly lower than the median of 51 (IQR 46 to 54) in patients who underwent delayed amputation after attempted reconstruction (p = 0.0351).Regression analysis identified three variables associated with a poor F&A score: negative Bohler's angle on initial radiograph; coexisting talus and calcaneus fracture; and tibial plafond fracture in addition to a hindfoot fracture. The presence of two out of three variables was associated with a significantly lower PCS compared with amputees (medians 29, IQR 27 to 43 vs 51, IQR 46 to 54; p < 0.0001). CONCLUSIONS: At five years, patients with reconstructed hindfoot fractures have inferior outcomes to those who have delayed amputation. It is possible to identify injuries which will go on to have particularly poor outcomes.Cite this article: P. M. Bennett, T. Stevenson, I. D. Sargeant, A. Mountain, J. G. Penn-Barwell. Outcomes following limb salvage after combat hindfoot injury are inferior to delayed amputation at five years. Bone Joint Res 2018;7:131-138. DOI: 10.1302/2046-3758.72.BJR-2017-0217.R2.

Efficient nonviral transfection of dendritic cells and their use for in vivo immunization.

Immunization with dendritic cells (DCs) transfected with genes encoding tumor-associated antigens (TAAs) is a highly promising approach to cancer immunotherapy. We have developed a system, using complexes of plasmid DNA expression constructs with the cationic peptide CL22, that transfects human monocyte-derived DCs much more efficiently than alternative nonviral agents. After CL22 transfection, DCs expressing antigens stimulated autologous T cells in vitro and elicited primary immune responses in syngeneic mice, in an antigen-specific manner. Injection of CL22-transfected DCs expressing a TAA, but not DCs pulsed with a TAA-derived peptide, protected mice from lethal challenge with tumor cells in an aggressive model of melanoma. The CL22 system is a fast and efficient alternative to viral vectors for engineering DCs for use in immunotherapy and research.

Gene therapy: the first decade.

Gene therapy promises to revolutionize medicine by treating the causes of disease rather than the symptoms. We are nearing the end of the first decade of gene therapy, and this article summarizes the approaches taken, results achieved, lessons learned and important recent developments. The early results on the clinical efficacy of gene therapies were disappointing, largely because the available gene-transfer vectors proved to be inadequate. Recently, however, clinical benefit has been clearly demonstrated and great progress made in selecting and improving vectors. There is now every prospect that the second decade will see gene therapy live up to its enormous potential.

Sequence analysis of the Bacillus subtilis argC promoter region.

A previously characterised promoter region upstream from the Bacillus subtilis argC gene was sequenced. The in vivo position of transcription start point (+1), was determined by mung-bean-nuclease mapping. The nucleotide (nt) sequences in the '-10' (TATAAT) and '-35' (TTGAAT) regions closely resemble consensus promoter sequences recognised by B. subtilis sigma 43 and Escherichia coli sigma 70 RNA polymerases. Between +9 and -64 are three imperfect inverted repeats with high homology to the E. coli arginine biosynthetic gene putative operator sequences (ARG boxes) [Cunin et al., Nucl. Acids Res. II (1985) 5007-5019] and which contain variable intra-repeat distances. Upstream from the '-35' region, extending as far as -71, is a 97% AT-rich sequence. The argC mRNA has a short leader region containing a B. subtilis ribosome-binding site 8 nt upstream from a TTG start codon for an open reading frame (ORF). The deduced amino acid sequence for this ORF contains regions of homology to that for the E. coli argC N-terminal region.

Co-expression of human protein disulphide isomerase (PDI) can increase the yield of an antibody Fab' fragment expressed in Escherichia coli.

Secretion to the periplasm of Escherichia coli enables production of many eukaryotic extracellular proteins in a soluble form. The complex disulphide bond arrangement of such proteins is probably a major factor in determining the low yield of correctly folded product observed in many cases. Here we show that co-expression of human protein disulphide isomerase increased the yield of a monoclonal antibody Fab' fragment in the periplasm of E. coli.

Expression of Escherichia coli B nitroreductase in established human tumor xenografts in mice results in potent antitumoral and bystander effects upon systemic administration of the prodrug CB1954.

Expression of the Escherichia coli enzyme nitroreductase (NTR) in mammalian cells enables them to activate the prodrug 5-(aziridin-1-yl)-2,4-dinitrobenzamide (CB1954), leading to interstrand DNA cross-linking and apoptosis in both proliferating and quiescent cells. In the work reported here, we used human hepatocellular carcinoma and squamous carcinoma cell lines constitutively expressing NTR to demonstrate that the ntr/CB1954 system results in potent, long-lasting antitumoral effects in mice. We also demonstrate that this enzyme/prodrug combination results in antitumoral effects in vivo when only a minority of tumor cells express the enzyme, using either cells constitutively expressing NTR or ntr gene delivery in situ.

Conversion of highly malignant colon cancer from an aggressive to a controlled disease by oral administration of a metalloproteinase inhibitor.

In this study, we describe the activity of CT1746, an orally-active synthetic MMP inhibitor that has a greater specificity for gelatinase A, gelatinase B and stromelysin than for interstitial collagenase and matrilysin, in a nude mouse model that better mimics the clinical development of human colon cancer. The model is constructed by surgical orthotopic implantation (SOI) of histologically-intact tissue of the metastatic human colon tumor cell line Co-3. Animals were gavaged with CT1746 twice a day at 100 mg/kg for 5 days after the SOI of Co-3 for 43 days. In this model CT1746 significantly prolonged the median survival time of the tumor-bearing animals from 51 to 78 days. Significant efficacy of CT1746 was observed on primary tumor growth (32% reduction in mean tumor area at day 36), total spread and metastasis (6/20 treated animals had no detectable spread and metastasis at autopsy compared to 100% incidence of secondaries in control groups). Efficacy of CT1746 could also be seen on reducing tumor spread and metastasis to individual organ sites such as the abdominal wall, cecum and lymph nodes compared to vehicle and untreated controls. We conclude that chronic administration of a peptidomimetic MMP inhibitor via the oral route is feasible and results in inhibition of solid tumor growth, spread and metastasis with increase in survival in this model of human cancer, thus converting aggressive cancer to a more controlled indolent disease.

Humanization of an anti-mucin antibody for breast and ovarian cancer therapy.

Antibody-drug conjugates utilize the targetting potential of antibodies to improve the potential of cytostatic or cytocidal drugs. One such murine monoclonal antibody, CTM01 (mCTM01), which recognizes an epitope on breast epithelial mucin, has potential for the treatment of breast and ovarian cancers. We examine in this paper the comparative properties of mCTM01 against a number of other anti-mucin antibodies. We then describe the humanization and high level re-expression of humanized CTM01 (hCTM01), a process designed to avoid the immune response to administered murine antibodies in human patients and to produce sufficient material for clinical studies. We show that the humanized form has properties superior to mCTM01 in terms of binding affinity to antigen presented on tumour cells.

Engineering antibodies for therapy.

For most MAb-based therapies single doses of MAbs or MAb conjugates will not be curative. Rodent MAbs are highly immonogenic in almost all patients. The HAMA response abrogates efficacy and can cause toxicity in organs of clearance, especially for MAb-cytotoxic agent conjugates. Humanization is the most promising generally applicable approach to overcoming the immunogenicity of rodent MAbs. Chimerization reduces immunogenicity in patients significantly, but not completely. Full humanization of rodent antibodies with retention of most of their antigen binding activity is now a routine procedure. The studies with 4D5 (Kelley et al., 1992), however, illustrate that even when antigen binding activity is retained, humanization may affect the overall conformation of the antibody in ways which influence its interaction with cells (for example when the antigen is internalized or involved in signal transduction) and hence its in vivo properties. As yet there are not sufficient data to judge whether full humanization will (in practical terms) completely overcome the immunogenicity problem in patients, but these data will be available within a year. Antibody fragments are the most promising general approach to manipulating the pharmacokinetics and biodistribution of therapeutic MAbs. Such fragments are clearly superior to whole IgGs for tumour detection and will very likely prove superior for tumour therapy also. MAb targeting of highly potent cytotoxic agents to tumours represents a much-needed approach to improving therapeutic ratios in cancer treatment. Radioisotopes and highly potent low molecular weight drugs are the most promising cell-killing agents for MAb targeting, and conjugation technology suitable for clinical use of some of the best of these agents has now been developed. Very encouraging data have already been obtained in clinical studies of haematopoietic malignancies with MAb-isotope conjugates. Tumour loading data from clinical studies suggest that killing of solid tumours in patients will be achievable in the near future with repeated administration of humanized antibody fragments carrying the superior isotopes or highly potent drugs which are now available.

Management of a complex hind foot war injury with negative pressure wound therapy: a case study.

We report the use of Negative Pressure Wound Therapy (NPWT) in a 39 year old patient with a complex open hind foot injury. The patient sustained an open calcaneal fracture with extensive soft tissue damage following the detonation of an explosively formed penetrating round in a confined space. A remarkable recovery was made following surgical debridement, internal fixation of the fracture and use of NPWT over the soft tissue injury. The patient returned to his normal level of function, without complications within a few months.

Bacillus subtilis 168 mutants resistant to arginine hydroxamate in the presence of ornithine or citrulline.

Mutations in Bacillus subtilis 168 have been isolated that confer resistance to arginine hydroxamate in the presence, but not absence, of ornithine. Seven such Ahor mutants have been studied in detail. In common with certain classes of Ahr mutant (resistant to arginine hydroxamate in the absence of arginine precursors) described previously, these Ahor mutants showed little or no inducibility of enzymes of arginine catabolism. Mutants that showed no inducibility were unable to utilize arginine or ornithine as sole nitrogen source. The only biosynthetic enzyme to show any consistent differences in activity from the parent was ornithine carbamoyltransferase, whose level was slightly elevated in cells grown in the presence of ornithine or citrulline. PBS1 transduction crosses showed that two of the ahor mutations map at the ahrA locus, while a third (unique in its resistance to arginine hydroxamate in the presence of citrulline) mapped at a hitherto undescribed locus closely linked to metC, designated ahrD.