Prevalence of post-traumatic neuropathic pain after digital nerve repair and finger amputation.

INTRODUCTION: Post-traumatic neuropathic pain is a major factor affecting the quality of life after finger trauma and is reported with considerable variance in the literature. This can partially be attributed to the different methods of determining neuropathic pain. The Douleur Neuropathique 4 (DN4) has been validated to be a reliable and non-invasive tool to assess the presence of neuropathic pain. This study investigated the prevalence of neuropathic pain after finger amputation or digital nerve repair using the DN4 questionnaire. METHODS: Patients with finger amputation or digital nerve repair were identified between 2011 and 2018 at our institution. After a minimal follow-up of 12 months, the short form DN4 (S-DN4) was used to assess neuropathic pain. RESULTS: A total of 120 patients were included: 50 patients with 91 digital amputations and 70 patients with 87 fingers with digital nerve repair. In the amputation group, 32% of the patients had pain, and 18% had neuropathic pain. In the digital nerve repair group, 38% of the patients had pain, and 14% had neuropathic pain. Secondly, of patient-, trauma-, and treatment-specific factors, only the time between trauma and surgery had a significant negative influence on the prevalence of neuropathic pain in patients with digital nerve repair. CONCLUSION: This study shows that persistent pain and neuropathic pain are common after finger trauma with nerve damage. One of the significant prognostic factors in developing neuropathic pain is treatment delay between trauma and time of digital nerve repair, which is of major clinical relevance for surgical planning of these injuries.

Prevention is better than cure: Surgical methods for neuropathic pain prevention following amputation - A systematic review.

BACKGROUND: Pain after amputation can be known as residual limb pain (RLP) or phantom limb pain (PLP); however, both can be disabling in daily life with reported incidences of 8% for finger amputations and up to 85% for major limb amputations. The current treatment is focused on reducing the pain after neuropathic pain occurs. However, surgical techniques to prevent neuropathic pain after amputation are available and effective, but they are underutilized. The purpose of the review is to investigate the effects of techniques during amputation to prevent neuropathic pain. METHODS: A systematic review was performed in multiple databases (Embase, Medline, Web of Science, Scopus, Cochrane, and Google Scholar) and following the PRISMA guidelines. Studies that reported surgical techniques to prevent neuropathic pain during limb amputation were included. RESULTS: Of the 6188 selected studies, 13 eligible articles were selected. Five articles reported techniques for finger amputation: neurovascular island flap, centro-central union (CCU), and epineural ligatures, and flaps. For finger amputations, the use of prevention techniques resulted in a decrease of incidences from 8% to 0-3% with CCU being the most beneficial. For major limb amputations, the incidences for RLP were decreased to 0 to 55% with TMR and RPNI and compared to 64-91% for the control group. Eight articles reported techniques for amputations on major limbs: targeted muscle reinnervation (TMR), targeted nerve implantation, concomitant nerve coaptation, and regenerative peripheral nerve interface (RPNI). CONCLUSIONS: Based on the current literature, we state that during finger and major limb amputation, the techniques to prevent neuropathic pain and PLP should be performed.

Development of a mental script for the mental practice of micro suturing: a methodological approach.

INTRODUCTION: Motor imagery and mental practice are important for the acquisition and mastery of surgical skills. The success of this technique relies on the use of a well-developed mental script. In this study, we shared how we developed a mental script for basic micro suturing training by using a low-fidelity rubber glove model. METHODS: This study applied the design and development research framework. Five expert surgeons developed a mental script by performing a cognitive walkthrough to repair a vertical opening in a rubber glove model, followed by hierarchical task analysis. A draft script was created, and its face and content validity assessed with a checking-back process. Twenty-eight surgeons used the Mental Imagery Questionnaire (MIQ) to assess the validity of the final script. RESULTS: The process of developing the mental script is detailed. The assessment by the expert panel showed the mental script had good face and content validity. The mean overall MIQ score was 5.2±1.1 (standard deviation), demonstrating the validity of generating mental imagery from the mental script developed in this study for micro suturing in the rubber glove model. CONCLUSION: The methodological approach described in this study is based on a design and development research framework to teach surgical skills. This model is inexpensive and easily accessible, addressing the challenges of reduced opportunities to practise surgical skills. However, although motor skills are important, the surgeon's other non-technical expertise is not addressed with this model. Thus, this model should act as one surgical training approach, but not replace it.

Integrating instructional design principles into surgical skills training models: an innovative approach.

OBJECTIVE: Surgical training programmes are evolving from time-based to competency-based schedules, which define expected learning outcomes in surgical knowledge, clinical and technical skills according to training levels. This article aims to review current models in surgical skills acquisition and to propose an integrative process-driven, outcomes-based model for surgical skills acquisition and mastery. DESIGN: A literature review was conducted on the theories of motor skills acquisition using PubMed, Web of Science and Google Scholar from 2010 to February 2020. The review was limited to theories and models on surgical skills acquisition and mastery. Four models of surgical skills acquisition were included: Fitts and Posner's three-stage model of motor skills acquisition, Bandura's social learning theory, Ericsson's deliberate practice model and Jeannerod's motor simulation theory. These models are deficient in that there is no universally accessible opportunity to practise the surgical procedure outside of the operating theatre and without access to physical simulators. RESULTS: We propose an innovative model that allows deliberate practice of the procedure without the need for expensive physical simulators, and provides an on-demand, self-directed practice by the trainees to achieve the level of mastery. This new model, which incorporates motor imagery and mental practice, augmented by deliberate practice, will provide an alternative training path for expert performance in surgical procedures. CONCLUSIONS: The innovative model provides a solution to the reduced opportunity for practice by surgical trainees to achieve mastery in surgical motor skills.

Towards gene therapy of postoperative adhesions: fiber and transcriptional modifications enhance adenovirus targeting towards human adhesion cells.

Postoperative abdominal/pelvic peritoneal adhesions are a major source of morbidity (bowel obstruction, infertility, ectopic gestation as well as chronic pelvic pain) in women. In this study, we screened various transduction and transcription modifications of adenovirus (Ad) to identify those that support maximal Ad-mediated gene delivery to human adhesion fibroblasts, which in turn would enhance the efficacy of this novel treatment/preventative strategy for postoperative adhesions. We transduced primary cultures of human peritoneal adhesion fibroblasts with fiber-modified Ad vectors Ad5-RGD-luc, Ad5-Sigma-luc, Ad5/3-luc and Ad5-CAV2-luc as well as transcriptional targeting viruses Ad5-survivin-luc, Ad5-heparanase-luc, Ad5-mesothelin (MSLN)-CRAd-luc and Ad5-secretory leukoprotease inhibitor (SLPI)-luc, and compared their activity to wild-type Ad5-luc. At 48 h, luciferase activity was measured and normalized to the total protein content in the cells. Among the fiber-modified Ad vectors, Ad5-Sigma-luc and among the transcriptional targeting modified Ad vectors, Ad5-MSLN-CRAd-luc showed significantly increased expression levels of luciferase activity at 5, 10 and 50 plaque forming units/cell in adhesion fibroblast cells compared with wild-type Ad5-luc (p < 0.05). Specific modifications of Ad improve their gene delivery efficiency towards human peritoneal adhesion fibroblasts. Developing a safe localized method to prevent/treat postoperative adhesion formation would have a major impact on women health.

Targeting adenoviral vectors for enhanced gene therapy of uterine leiomyomas.

STUDY QUESTION: Is targeted adenovirus vector, Ad-SSTR-RGD-TK (Adenovirus -human somatostatin receptor subtype 2- arginine, glycine and aspartate-thymidine kinase), given in combination with ganciclovir (GCV) against immortalized human leiomyoma cells (HuLM) a potential therapy for uterine fibroids? SUMMARY ANSWER: Ad-SSTR-RGD-TK/GCV, a targeted adenovirus, effectively reduces cell growth in HuLM cells and to a significantly greater extent than in human uterine smooth muscle cells (UtSM). WHAT IS KNOWN ALREADY: Uterine fibroids (leiomyomas), a major cause of morbidity and the most common indication for hysterectomy in premenopausal women, are well-defined tumors, making gene therapy a suitable and potentially effective non-surgical approach for treatment. Transduction of uterine fibroid cells with adenoviral vectors such as Ad-TK/GCV (herpes simplex virus thymidine kinase gene) decreases cell proliferation. STUDY DESIGN, SIZE, DURATION: An in vitro cell culture method was set up to compare and test the efficacy of a modified adenovirus vector with different multiplicities of infection in two human immortalized cell lines for 5 days. PARTICIPANTS/MATERIALS, SETTING, METHODS: Immortalized human leiomyoma cells and human uterine smooth muscle cells were infected with different multiplicities of infection (MOI) (5-100 plaque-forming units (pfu)/cell) of a modified Ad-SSTR-RGD-TK vector and subsequently treated with GCV. For comparison, HuLM and UtSM cells were transfected with Ad-TK/GCV and Ad-LacZ/GCV. Cell proliferation was measured using the CyQuant assay in both cell types. Additionally, western blotting was used to assess the expression of proteins responsible for regulating proliferation and apoptosis in the cells. MAIN RESULTS AND THE ROLE OF CHANCE: Transduction of HuLM cells with Ad-SSTR-RGD-TK/GCV at 5, 10, 50 and 100 pfu/cell decreased cell proliferation by 28, 33, 45, and 84%, respectively (P < 0.05) compared with untransfected cells, whereas cell proliferation in UtSM cells transfected with the same four MOIs of Ad-SSTR-RGD-TK/GCV compared with that of untransfected cells was decreased only by 8, 23, 25, and 28%, respectively (P < 0.01). Western blot analysis showed that, in comparison with the untargeted vector Ad-TK, Ad-SSTR-RGD-TK/GCV more effectively reduced expression of proteins that regulate the cell cycle (Cyclin D1) and proliferation (PCNA, Proliferating Cell Nuclear Antigen), and it induced expression of the apoptotic protein BAX, in HuLM cells. LIMITATIONS, REASONS FOR CAUTION: Results from this study need to be replicated in an appropriate animal model before testing this adenoviral vector in a human trial. WIDER IMPLICATIONS OF THE FINDINGS: Effective targeting of gene therapy to leiomyoma cells enhances its potential as a non-invasive treatment of uterine fibroids.

Interdisciplinary Global Health Forum: conference report.

In spring of 2012, students and staff at the First Faculty of Medicine at Charles University in Prague invited distinguished public health stakeholders and experts to engage in a Global Health Forum. The forum lasted an afternoon, was academically and clinically engaging and offered students and medical faculty a venue to discuss the most pressing global public health concerns. Main outcomes from the forum included describing outstanding public issues in public health policy and prevention, infectious disease and public health systems raised by the speakers, stakeholders and attendees. One major result of this forum is the establishment of the Prague Center for Global Health - an interdepartmental and interdisciplinary research collaborative to further the discussion and much needed field and academic research in global public health. The Prague Center for Global Health will include multiple international research centers and main function and results will include new courses at the university, publications based on best practices and research and a venue to learn, share and create in the academic space.

Digital video documentation as evidence of clinical skill acquisition.

Video recordings have become requirements for the assessment and recording of the consulting skills module of the MRCGP examination and surgical skill modules for the post FRCS hand diploma examination. Previous research has shown that the knowledge and judgement skills needed by trainees to achieve operative competence can be reliably assessed using structured checklists. However evaluation of surgical competency should also include technical skills, which have been difficult to document adequately and transparently. There is now evidence demonstrating that surgeons can discriminate between the video recordings of a competent and non-competent trainee. Like those of previous researchers our findings indicate that intra-operative video monitoring enables an objective and permanent recordable assessment of the a trainees skill level whilst completing the checklist after a particular procedure. Video evidence can also be distributed widely to assessors outside the trainee's locale.

The diagnostic accuracy of clinical examination in hand lacerations.

INTRODUCTION: Hand injuries account for a significant proportion of emergency department attendance. We investigated the diagnostic accuracy of clinical examination in patients with simple hand lacerations undergoing surgical exploration at our unit. METHODS: One hundred and sixty-five consecutive patients were identified as undergoing exploration of the hand. Case notes of these patients were reviewed. The clinical findings, made by emergency department doctors (ED) and hand surgeons (HS), were compared with the operative findings. RESULTS: A total of 101 patients were included following exclusion criteria. Both ED and HS correctly identified 68.2% of flexor tendon injuries. Overall, the ED diagnosed accurately significantly fewer extensor tendon injuries (ED 65.6% vs HS 75.0%, p<0.001). Similarly, HS diagnosed nerve injuries more accurately than ED (ED 54.5% vs HS 78.8%, p<0.005). DISCUSSION: Clinical examination forms an important part of the patient assessment, provides the surgeon with an idea of which structures are potentially injured, and its value should never be underestimated. Formal exploration, however, should be undertaken since both ED and HS missed about 30% injuries.

Surgical process re-engineering: carpal tunnel decompression--a model.

Surgical process re-engineering is a methodology where the entire surgical process is systematically analysed and re-designed. The process starts with mapping of the current process followed by in-depth analysis of the existing process. A new process is drafted with the aim of making the whole procedure more efficient. The new process is then discussed with all the staff involved in the operating room. Following implementation of the process, surgical process re-engineering should ideally be routinely carried out to continuously improve the procedure. We present an example of surgical process re-engineering which we carried out on the procedure of carpal tunnel release. We used carpal tunnel release as a model as it is a very common operation, with predictable intra-operative findings, and the patient is likely to benefit directly from procedure time reduction. A preliminary mapping of three procedures was done followed by a detailed timed mapping of five routine carpal tunnel decompression procedures. The mapped process was analysed in detail and a number of changes were made in the process. After implementing the new process, a further five procedures were mapped and timed again. In comparison to the original process, we achieved a reduction of 20% in the mean procedure time and a reduction of 42% in the number of steps from 66 to 37.

The effect of an angiostatic steroid on neovascularization in a rat model of retinopathy of prematurity.

PURPOSE: The inhibition of angiogenesis by angiostatic steroids has been demonstrated in a variety of systems, including rabbit and rat cornea. There is considerable interest in the therapeutic potential of this class of compounds for angiogenic ocular conditions such as diabetic retinopathy, macular degeneration, and retinopathy of prematurity (ROP). This study was designed to test the capacity of an angiostatic steroid, anecortave acetate, to inhibit retinal neovascularization using a rat model of ROP and to investigate the mechanism of the effect. METHODS: At birth, rats were placed in an atmosphere of varying oxygen that produces retinal neovascular changes that approximate human ROP. The rats then received intravitreal injections of either anecortave acetate or vehicle at varying times, and all were subsequently placed in room air. Retinas were assessed for plasminogen activator inhibitor (PAI)-1 mRNA level by RNase protection assay at 1, 2, and 3 days after injection and for normal and abnormal blood vessel growth 3 days later. RESULTS: A significant reduction in the severity of abnormal retinal neovascularization was observed in the steroid-treated eyes compared with vehicle-injected eyes in ROP rats, yet the extent of normal total retinal vascular area was not significantly different. The drug had no effect on either retinal vascular area or neovascularization when tested in room air-raised control rats. Drug-injected eyes demonstrated a six- to ninefold increase in PAI-1 mRNA at 1 to 3 days after injection. CONCLUSIONS: This study represents the first therapeutic effect of an angiostatic steroid in an animal model of neovascular retinopathy. Additionally, the induction of PAI-1 indicates a mechanism of action for this class of compounds, and this is a novel finding in vivo. Because anecortave acetate significantly inhibited pathologic retinal angiogenesis in this model, while not significantly affecting normal intraretinal vessels, it holds therapeutic potential for a number of human ocular conditions in which angiogenesis plays a critical pathologic role.

Evidence for upregulation and redistribution of vascular endothelial growth factor (VEGF) receptors flt-1 and flk-1 in the oxygen-injured rat retina.

There is considerable evidence that vascular endothelial growth factor (VEGF) is important in the pathogenesis of retinal neovascular diseases. The effects of this endothelial cell-specific mitogen are mediated by specific cell surface receptors. In this study we probed for the two VEGF receptors (VEGFRs) known to have highest affinity in the rat--flt-1 and flk-1. Using a well-characterized rat model of the neovascular disease retinopathy of prematurity (ROP), we performed immunohistochemical assays on methacrylate sections of eyes from normal and oxygen-injured animals at the time neovascularization is first observed (16 days of age) and at its peak (day 20). In day 16 room air retinas there was light, diffuse labeling of the inner nuclear layer and outer plexiform layer. In contrast, in 4 of 5 oxygen-injured eyes on day 16, there was specific labeling of small neovascular growths and normal retinal vessels, and the outermost (sclerad) limit of the label had shifted inward to the vitread border of the inner nuclear layer and the inner plexiform layer. Day 20 room air eyes showed a pattern similar to day 16, although with stronger labeling. However, in oxygen-injured eyes on day 20 the labeling pattern had shifted toward the vitreous, with extremely strong labeling of the preretinal neovascular growths. As on day 16 there was also labeling of the inner plexiform layer and the inner portion of the inner nuclear layer, but not the outer plexiform layer. Comparison of VEGF protein immunolabel with both of the VEGFR immunolabels revealed overlap and strong similarity on day 20 in the oxygen-injured eyes. This is the first report of VEGF receptor protein being concentrated in preretinal neovascular growths in a model of ROP. These results lend themselves to further investigation of the roles of VEGFRs in preretinal neovascularization in ROP and other retinal diseases and suggest avenues of research toward therapies using VEGFR antagonists.

Maternal diabetes induces upregulation of hepatic insulin-like growth factor binding protein-1 MRNA expression, growth retardation and developmental delay at the same stage of rat fetal development.

Since maternal diabetes is associated with fetal growth abnormalities in humans and rats, effects of maternal diabetes on fetal expression of genes regulating growth are of interest. Increased expression of Insulin-Like Growth Factor Binding Protein-I (IGFBP-1) is associated with several examples of growth retardation and is upregulated in response to diabetes. As we have shown previously, IGFBP-1 expression is upregulated in gestational day (GD) 14 rat fetuses in response to maternal diabetes. Here we analyze the effect of streptozotocin-induced maternal diabetes on IGFBP-1 mRNA expression during GD12-16 of rat fetal development, using in situ hybridization. IGFBP-1 mRNA was more abundant in GD12-14 fetal livers from diabetic dams than in livers of age-matched controls. This upregulation is not due to the approximately 1-day fetal developmental delay associated with maternal diabetes, as there is no gross difference in the level of IGFBP-1 mRNA in GD13 vs GD12 or GD14 vs GD13 control fetal livers. At GD15-16, however, we detected little difference in IGFBP-1 expression between experimental and control fetuses. This transient period of maternal diabetes-stimulated IGFBP-1 mRNA expression (GD12-14) is coincident with the sensitive period for maternal diabetes-induced defects in fetal growth and development, suggesting that IGFBP-1 is involved in the regulation of fetal growth and development in response to the maternal condition.

Isolation, characterization and complete nucleotide sequence of a Galleria mellonella cDNA coding for the follicle cell-specific yolk protein, YP4.

An ovariole-specific yolk polypeptide cDNA from Galleria mellonella was isolated from a cDNA library constructed using vitellogenic ovariole poly (A)+ RNA, by differential screening with the ovariole and day-0 male pupal poly (A)+ RNA. The Ov11 cDNA hybridized to a 1.1 kb message from the ovariole but not from male pharate adults, ovariectomized pharate adults or day-5 last instar larvae. Developmental Northern analysis showed that this message is expressed only during vitellogenic stages. In situ hybridization of digoxigenin-dUTP labeled Ov11 cDNA to the day-8 pharate adult ovariole showed that only follicle cells express the Ov11 gene. The 960 bp Ov11 cDNA is nearly full-length, containing a single open reading frame coding for a 286 amino acid polypeptide with a hydrophobic signal sequence and two potential N-glycosylation and tyrosine sulfation sites. The fact that Ov11 cDNA codes for the 37 kDa ovariole-specific yolk protein, YP4, was confirmed by the N-terminal amino acid sequence analysis of purified YP4. Genomic Southern analysis suggests that the yp4 gene is a single copy gene and PCR analysis using the 5' and 3' end primers of the cDNA indicates that the yp4 gene is intronless within the coding region.

Effects of maternal diabetes on fetal expression of insulin-like growth factor and insulin-like growth factor binding protein mRNAs in the rat.

Maternal diabetes is associated in humans and rats with an increased risk for fetal growth abnormalities and malformations. Therefore, the effect of maternal diabetes on expression of genes that regulate fetal growth and differentiation is of considerable interest. Developmental growth is regulated in part by the expression and availability of insulin-like growth factors (IGFs). Postnatal expression of a subset of the IGFs and IGF binding proteins (IGFBPs) has been demonstrated to be regulated in response to diabetes and other metabolic conditions. We used in situ hybridization to analyze the effect of maternal diabetes, induced by streptozotocin (STZ) prior to mating, upon prenatal rat IGF and IGFBP mRNA expression. At gestational day (GD) 14, the most striking effect of maternal diabetes on fetal IGF/IGFBP gene expression was a marked increase in the abundance of IGFBP-1 mRNA within the liver primordia of fetuses isolated from diabetic dams compared to age-matched controls. This upregulation cannot be entirely due to the approximately one-half-day delay in fetal development (based on limb bud staging) associated with maternal diabetes, as there was no gross difference in the level of IGFBP-1 mRNA between GD13 and GD14 control fetal livers. In contrast, the fetal mRNA expression patterns of IGF-I, IGF-II and IGFBP-2, -3, -4, -5 and -6 were not grossly altered by maternal diabetes. These data are consistent with the hypothesis that IGFBP-1 produced within the fetal liver and secreted into fetal circulation may play a role in regulating rat fetal growth.

Nucleotide sequence, structure and developmental regulation of LHP82, a juvenile hormone-suppressible hexamerin gene from the waxmoth, Galleria mellonella.

We cloned and sequenced a composite cDNA corresponding to the 2.6 kb last instar-specific, juvenile hormone-suppressible Lhp82 mRNA from Galleria mellonella. The identity of the cDNA was confirmed by N-terminal amino acid sequencing of the purified Lhp82 subunit. In addition, we sequenced all coding regions and most of the intronic DNA as well as 1300 nucleotides of 5' flanking DNA from the Lhp82 gene. The eight exons of the Lhp82 gene specify a pre-protein of 706 residues, including the signal peptide of 18 amino acids. The deduced amino acid sequence of Lhp82 contains four potential N-glycosylation sites, and the calculated isoelectric point and molecular weight of secreted Lhp82 are pI = 6.43 and 79.9 kDa, respectively. Inspection of the 5' flanking and intronic regions of Lhp82 DNA revealed a 301 nucleotide cassette in intron 6 that appears to be a recently inserted repetitive element. We also performed Northern blot and nuclear run-off transcription experiments in order to determine the basis for Lhp82 gene inactivity after day 2 of the pupal stage. The results of these studies indicate that Lhp82 transcription is permanently shut off by the ecdysteroid pulse which occurs in the absence of juvenile hormone beginning 24 h post-pupation.