Self-Assembly and Host-Guest Interactions of Pd3L2 Metallo-cryptophanes with Photoisomerizable Ligands.

New photoswitchable pyridyl-azo-phenyl-decorated tripodal host ligands (Laz) that belong to the cyclotriveratrylene family have been synthesized, and their photoswitching behavior and crystal structures determined. The latter includes a remarkable 7-fold Borromean-weave entanglement of π-π stacked layers. Trigonal bipyramidal {[Pd(en)]3(Laz)2}6+ metallo-cryptophanes (en = ethylenediamine) were formed from these and a previously known pyridyl-azo-phenyl-decorated tripodal host ligand. These coordination cages dissociate at low concentrations and are less robust to photoswitching of the Laz ligands than were previously reported Ir(III)-linked metallo-cryptophanes with similar ligands, reflecting the greater lability of the Pd-N bonds. The {[Pd(en)]3(Laz)2}6+ cages all act as hosts, binding octyl sulfate anions, or N-[2-(dimethylamino)ethyl]-1,8-naphthalimide in a dimethyl sulfoxide solution.

Hereditary haemochromatosis, haemophagocytic lymphohistiocytosis and COVID-19.

BACKGROUND: Syndromes of iron overload have been shown to increase the risk of severe clinical disease in viral infections. Immune dysfunction is similarly described in hereditary haemochromatosis (HH). We present here the case of a 51-year-old man who developed severe coronavirus disease 2019 (COVID-19) complicated by suspected haemophagocytic lymphohistiocytosis (HLH). He was found to have HH post-mortem and we propose a link between his iron overload and the development of severe COVID-19. CASE REPORT: The initial clinical presentation consisted of cough, shortness of breath and fever. Pancytopenia, markedly elevated ferritin and d-dimer were present. Computed tomography (CT) showed bilateral ground glass changes consistent with COVID-19, widespread lymphadenopathy and splenomegaly. A subsequent combined nose and throat swab was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). HLH was suspected based upon the H-score and Anakinra, an IL-1 receptor antagonist, was commenced. Liver function acutely worsened and magnetic resonance cholangiopancreatography (MRCP) revealed hepatic haemosiderosis. Intense splenic and cervical lymph node uptake were seen on a positron emission tomography (PET) scan and high doses of intravenous steroids were administered due to concerns over haematological malignancy. RESULTS: Day fourteen of admission heralded the start of progressive clinical deterioration with rapid increase in oxygen demands. Continuous positive airway pressure (CPAP) was trialled without success and the patient unfortunately died seventeen days into admission. Results returned after his death showed homozygous C282Y mutation of the HFE gene consistent with a diagnosis of HH. Post-mortem examination revealed widespread haemosiderin deposition in the liver along with lung pathology in keeping with severe COVID-19 and widespread splenic infarctions. CONCLUSION: An association between HH and COVID-19 is not currently described in the literature. What does exist, however, is an evidence base for the detrimental impacts iron overload has on viral infections in general and the negative effects of HH on the immune system. We therefore postulate that the underlying metabolic and immune disturbances seen in HH should be considered a potential risk factor for the development of severe COVID-19. This case also adds to the evidence that hyperinflammation appears to be a unique and interesting characteristic of this novel viral disease.

Repurposing of KLF5 activates a cell cycle signature during the progression from a precursor state to oesophageal adenocarcinoma.

Oesophageal adenocarcinoma (OAC) is one of the most common causes of cancer deaths. Barrett's oesophagus (BO) is the only known precancerous precursor to OAC, but our understanding about the molecular events leading to OAC development is limited. Here, we have integrated gene expression and chromatin accessibility profiles of human biopsies and identified a strong cell cycle gene expression signature in OAC compared to BO. Through analysing associated chromatin accessibility changes, we have implicated the transcription factor KLF5 in the transition from BO to OAC. Importantly, we show that KLF5 expression is unchanged during this transition, but instead, KLF5 is redistributed across chromatin to directly regulate cell cycle genes specifically in OAC cells. This new KLF5 target gene programme has potential prognostic significance as high levels correlate with poorer patient survival. Thus, the repurposing of KLF5 for novel regulatory activity in OAC provides new insights into the mechanisms behind disease progression.

Acid fluids present in the gut can sometimes 'go up' and damage the oesophagus, the pipe that connects the mouth and the stomach. As a result, a small number of individuals can develop Barrett's oesophagus, a condition where cells in the lining of the lower oesophagus show abnormal shapes. In certain patients, these cells then become cancerous, but exactly how this happens is unknown. This lack of understanding contributes to late diagnoses, limited treatment and low survival rates. Many cancers feature 'signature' mutations in a set of genes that controls how a cell can multiply. Yet, in the case of cancers of the lower oesophagus, known genetic changes have had a limited impact on our understanding of the emergence of the disease. Here, Rogerson et al. focused instead on non-genetic changes and studied transcription factors, the proteins that bind to regulatory regions of the DNA to switch genes on and off. A close inspection of cancer cells in the lower oesophagus revealed that, in that state, a transcription factor called KLF5 controls the abnormal activation of genes involved in cell growth. This is linked to the transcription factor adopting a different pattern of binding onto regulatory regions in diseased cells. Crucially, when the cell growth genes regulated by KLF5 are activated, patients have lower survival rates. Further work is now required to examine whether this finding could help to identify patients who are most at risk from developing cancer. More broadly, the results from the work by Rogerson et al. demonstrate how transcription factors can be repurposed in a disease context.

Cyclotriveratrylene-tethered trinuclear palladium(ii)-NHC complexes; reversal of site selectivity in Suzuki-Miyaura reactions.

The trinuclear complexes [{PdI2(pyCl)}3(L1)] C1 and [{PdI2(pyCl)}3(L2)] C2, where pyCl = 3-chloropyridine, L1 = methyl(cyclotriguaiacylenyl)methylbenzimidazol-2-ylidene and L2 = benzyl(cyclotriguaiacylenyl)methylbenzimidazol-2-ylidene, each feature three palladium N-heterocyclic carbene (NHC) centres tethered onto a host-type cyclotriguaiacylene scaffold. Crystal structures of different solvates of complex C1 reveal different host-guest motifs including intra-cavity binding of dioxane guests concomitant with intramolecular halogen bonding interactions of C1. Mononuclear NHC analogues of C1 and C2, namely [PdI2(pyCl)(L3)] C3 and [PdI2(pyCl)(L4)] C4, where L3 = (3-chloropyridyl)-1-(2-methoxyphenyoxy)methyl-3-methylbenzimidazol-2-ylidene and L4 = (3-chloropyridyl)-1-(2-methoxyphenyoxy)methyl-3-benzylbenzimidazol-2-ylidene, were also synthesised and their crystal structures determined. Complexes C1-C4 are competent catalysts for Suzuki Miyaura cross-coupling, and interestingly exhibit a switch in the normal regioselectivity observed for reactions of 2,4-dibromopyridine with aryl boronic acids, usually C2-selective, yielding C4-arylated product preferentially over C2-arylated product.

Identification of a primitive intestinal transcription factor network shared between esophageal adenocarcinoma and its precancerous precursor state.

Esophageal adenocarcinoma (EAC) is one of the most frequent causes of cancer death, and yet compared to other common cancers, we know relatively little about the molecular composition of this tumor type. To further our understanding of this cancer, we have used open chromatin profiling to decipher the transcriptional regulatory networks that are operational in EAC. We have uncovered a transcription factor network that is usually found in primitive intestinal cells during embryonic development, centered on HNF4A and GATA6. These transcription factors work together to control the EAC transcriptome. We show that this network is activated in Barrett's esophagus, the putative precursor state to EAC, thereby providing novel molecular evidence in support of stepwise malignant transition. Furthermore, we show that HNF4A alone is sufficient to drive chromatin opening and activation of a Barrett's-like chromatin signature when expressed in normal human epithelial cells. Collectively, these data provide a new way to categorize EAC at a genome scale and implicate HNF4A activation as a potential pivotal event in its malignant transition from healthy cells.

Author Correction: Authentication and characterisation of a new oesophageal adenocarcinoma cell line: MFD-1.

A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Open chromatin profiling identifies AP1 as a transcriptional regulator in oesophageal adenocarcinoma.

Oesophageal adenocarcinoma (OAC) is one of the ten most prevalent forms of cancer and is showing a rapid increase in incidence and yet exhibits poor survival rates. Compared to many other common cancers, the molecular changes that occur in this disease are relatively poorly understood. However, genes encoding chromatin remodeling enzymes are frequently mutated in OAC. This is consistent with the emerging concept that cancer cells exhibit reprogramming of their chromatin environment which leads to subsequent changes in their transcriptional profile. Here, we have used ATAC-seq to interrogate the chromatin changes that occur in OAC using both cell lines and patient-derived material. We demonstrate that there are substantial changes in the regulatory chromatin environment in the cancer cells and using this data we have uncovered an important role for ETS and AP1 transcription factors in driving the changes in gene expression found in OAC cells.

Combined All-Inside Anterior Cruciate Ligament Reconstruction and Minimally Invasive Posterolateral Corner Reconstruction Using Ipsilateral Semitendinosus and Gracilis Autograft.

The anterior cruciate ligament (ACL) is the most commonly injured knee ligament, particularly among adolescents and young adults. Unrecognized posterolateral laxity is understood as a major cause of ACL reconstruction failure, and concomitant injury to the posterolateral corner (PLC) is prevalent and underdetected. We advocate screening all ACL-deficient knees for PLC injury and present a technique combining minimally invasive PLC reconstruction with anatomic all-inside ACL reconstruction. The combined procedure uses only the ipsilateral hamstring tendons representing a major surgical advantage over traditional management approaches. The semitendinosus is quadrupled and attached to 2 adjustable suspensory cortical fixation devices to form the ACL graft. The gracilis tendon is looped through the fibula head and secured in a single femoral tunnel for the PLC reconstruction via 2 minimally invasive incisions. The use of a single femoral PLC tunnel combined with a single femoral ACL socket minimizes the risk of tunnel convergence.

Transmedial All-inside TriLink Posterior Cruciate Ligament Reconstruction.

Posterior cruciate ligament (PCL) injuries usually constitute part of a multiligament injury. Isolated PCL injuries account for only approximately 3% of all ligament injuries. No consensus on optimal surgical reconstruction exists. The PCL is a double-bundle structure that functions in an anisometric manner. Biomechanical studies have shown that re-creating the PCL femoral double-bundle configuration provides greater stability. We present a 3-socket approach for an anatomic "all-inside" double-bundle PCL reconstruction using our preferred option of a FiberTape (Arthrex, Naples, FL)-reinforced peroneus longus allograft fashioned to create a trifurcate graft: the TriLink technique. Cortical suspensory fixation devices are used, allowing differential tensioning of the anterolateral and posteromedial bundles. This enables more accurate replication of the native PCL and its biomechanical properties.

A prospective case series for a minimally invasive internal fixation device for anterior pelvic ring fractures.

BACKGROUND: External fixation is commonly used as a means of definitive fixation of pelvic fractures. Pin site infection is common, with some cases of osteomyelitis and inpatient nursing can be challenging. The aim of this study is to report the outcomes and complications of an alternative minimally invasive technique, known as INFIX, utilising spinal pedicle screws inserted into the supra-acetabular bone and connected by a subcutaneous rod. METHODS: A single-centre prospective case series was performed. The primary outcome measures were fracture stability and displacement at time of implant removal and intra- and post-operative complications. RESULTS: Twenty-one patients were recruited, with 85.7 % of fractures being lateral compression type. Mean follow-up was 342 days. Mean application time was 51 min (range 44-65). Nineteen were removed electively, with mean time to removal 109 days. All cases were stable with no displacement. Two cases were removed emergently, one due to wound infection and the other due to lateral femoral cutaneous nerve neuropathic pain. Twelve patients sustained a lateral femoral cutaneous nerve palsy, with 20/42 nerves being affected. Improvement in all lateral femoral cutaneous nerve symptoms were reported with removal. Nine patients developed asymptomatic heterotopic ossification, and there were three deep infections and one symptomatic due to the bar. CONCLUSIONS: Minimally invasive internal fixation with the INFIX for anterior pelvic ring fractures is an alternative to anterior external fixation. However, a higher rate of lateral femoral cutaneous nerve palsy is noted, and the implant is not well tolerated by all patients. Further studies are required to define fracture types and patients best suited to the technique and how LFCN complications may be minimised. TRIAL REGISTRATION: ACTRN12616001421426 . Registered 12 October 2016. Retrospectively registered.

Authentication and characterisation of a new oesophageal adenocarcinoma cell line: MFD-1.

New biological tools are required to understand the functional significance of genetic events revealed by whole genome sequencing (WGS) studies in oesophageal adenocarcinoma (OAC). The MFD-1 cell line was isolated from a 55-year-old male with OAC without recombinant-DNA transformation. Somatic genetic variations from MFD-1, tumour, normal oesophagus, and leucocytes were analysed with SNP6. WGS was performed in tumour and leucocytes. RNAseq was performed in MFD-1, and two classic OAC cell lines FLO1 and OE33. Transposase-accessible chromatin sequencing (ATAC-seq) was performed in MFD-1, OE33, and non-neoplastic HET1A cells. Functional studies were performed. MFD-1 had a high SNP genotype concordance with matched germline/tumour. Parental tumour and MFD-1 carried four somatically acquired mutations in three recurrent mutated genes in OAC: TP53, ABCB1 and SEMA5A, not present in FLO-1 or OE33. MFD-1 displayed high expression of epithelial and glandular markers and a unique fingerprint of open chromatin. MFD-1 was tumorigenic in SCID mouse and proliferative and invasive in 3D cultures. The clinical utility of whole genome sequencing projects will be delivered using accurate model systems to develop molecular-phenotype therapeutics. We have described the first such system to arise from the oesophageal International Cancer Genome Consortium project.

Paediatric ACL repair reinforced with temporary internal bracing.

PURPOSE: Instability following non-operative treatment of anterior cruciate ligament (ACL) rupture in young children frequently results in secondary chondral and/or meniscal injuries. Therefore, many contemporary surgeons advocate ACL reconstruction in these patients, despite the challenges posed by peri-articular physes and the high early failure rate. We report a novel management approach, comprising direct ACL repair reinforced by a temporary internal brace in three children. METHODS: Two patients (aged 5 and 6 years) with complete proximal ACL ruptures and a third (aged seven) with an associated tibial spine avulsion underwent direct surgical repair, supplemented with an internal brace that was removed after 3 months. RESULTS: Second-look arthroscopy, examination and imaging at 3 months confirmed knee stability and complete ACL healing in all cases. Normal activities were resumed at 4 months, and excellent objective measures of function, without limb growth disturbance, were noted beyond 2 years. CONCLUSION: ACL repair in young children using this technique negates the requirement and potential morbidity of graft harvest and demonstrates the potential for excellent outcome as an attractive alternative to ACL reconstruction, where an adequate ACL remnant permits direct repair. LEVEL OF EVIDENCE: IV.

The new neck of femur fracture target: experience in a district general hospital.

PURPOSE: The hip fracture "best practice tariff" (BPT) came into effect in April 2010. It advocated two key improvements: surgery within 36 hrs of arrival in the emergency department; and multi-disciplinary care directed by ortho-geriatrician from admission to discharge. The aim of this paper is to look at the 36 hours to operation target and its implications for orthopaedic department trauma service staff in a busy district general hospital, and to evaluate the measures implemented to meet the target. DESIGN/METHODOLOGY/APPROACH: Trauma-list data, collected from a theatre management system, was compared with trauma patients placed on elective and emergency lists, before and after designated daily trauma lists were implemented. FINDINGS: After a designated daily trauma list was introduced, a significant rise (from 56 per cent to 85 per cent) became evident in the proportion of patients operated on within 36 hrs, between November 2010 to February 2011, while hip fracture cases managed on the elective list fell from 24 per cent to 17 per cent. PRACTICAL IMPLICATIONS: Despite adding a half-day trauma list, the trauma service has insufficient capacity to achieve the new BPT for all hip fracture patients in the hospital. Therefore, there is a significant knock-on effect for managing patient overspill on elective services. Will the significant changes in service provision designed to achieve this BPT be cost effective? ORIGINALITY/VALUE: This paper aims to answer how busy department staff address an issue that professionals in every English hospital are facing.

Ageing and the gut.

The goal of this brief review is to address the role of the ageing gut in the genesis of malnutrition in the elderly. We assess the burden of malnutrition in the elderly, exploring the role of comorbid conditions and neurohumoral changes that take place to contribute towards the process of anorexia associated with ageing. Following this, the review assesses physiological changes that occur in each part of the gastrointestinal (GI) tract and what implication they may have in clinical practice. In the oropharynx and the oesophagus, changes in swallowing and oesophageal motility associated with ageing can be demonstrated using physiological testing. However, in the absence of comorbid disease, they often have little, if any, clinical significance. In the stomach, reduced fundal compliance may contribute to early satiety; however, the primary change is hypochlorhydria, which may predispose to malabsorption or bacterial overgrowth further along the GI tract. Almost uniquely, the small bowel, particularly its absorptive function, is unaffected by age and we review the literature demonstrating this. In the colon, there is evidence of a prolonged transit time related to a reduction in both neurotransmitters and receptors. Although this may cause symptoms, this aspect is unlikely to contribute to malnutrition. In addition, we assess the potential changes in the gut microbiome and how this may interact with the immune system in the process of 'inflamm-ageing'. We conclude by summarising the main changes and their impact for the clinician along with recommendations for future areas of research.

Direct bony invasion of malignant melanoma.

Malignant melanoma is known to spread by local extention, by the lymphatics by the blood stream. Direct invasion of the bone from a cutaneous melanoma is unknown. Hence, this case is presented in view of its rarity. A 75-year-old Caucasian lady presented with a small papillary lesion in the region of a recurrent chronic cellulitis on the lower third of the lateral aspect of the right leg. Histopathology diagnosed the lesion as locally advanced malignant melanoma. Radiological investigations by X-ray and magnetic resonance imaging revealed malignant infiltration of the tibia in its mid and lower third with two soft tissue metastatic masses adjacent. Histology following amputation confirmed malignant melanoma with cranial resection margin involvement. She underwent a further above-knee amputation followed by chemotherapy. The patient recovered from the amputation but subsequently died 6 months later due to bronchopneumonia from lung metastasis.

Orthopaedic procedure coding. Does accuracy matter?

PURPOSE: Coding clinical work should allow accurate and precise methods of assessing individual or department activity. The NHS financial reforms have increased correct diagnostic coding importance by introducing "payment by results" so that funding is directly linked to patient activity. The aim of this study is to assess the accuracy of procedure codes (OPCS 4.4), and its effect on Healthcare Resource Group tariff codes that directly affect revenue. DESIGN/METHODOLOGY/APPROACH: A total of ten procedures from ten consultants were randomly selected over one month. Each consultant coded his or her own procedures. From these codes, Healthcare Resource Group tariff codes were assigned to each patient. These were compared with procedure and Healthcare Resource Group tariff codes generated by coding department staff. FINDINGS: Of 100 procedures, four were un-coded by coding department staff. There was concordance in 35 per cent of cases. Coders only gave one code for each procedure, whereas 35 per cent of procedures coded by consultants were assigned multiple codes. This resulted in 27 per cent of cases generating a different Healthcare Resource Group tariff code. Of the cases, five resulted in a difference of pound 4,000 or more; however, the overall difference was a pound 3,367 revenue loss if coder's codes were used. RESEARCH LIMITATIONS/IMPLICATIONS: Study numbers were limited to 100 with five cases showing excessive financial gain or loss significantly influencing the overall result. PRACTICAL IMPLICATIONS: Present procedure coding practice is inaccurate and results in Healthcare Resource Group tariff codes that do not accurately represent clinical activity and productivity. Under payment by results, this can result in a significant revenue loss and possibly ultimately future referrals. Therefore, coding practice needs to be improved as a matter of urgency. Arguably, this could be achieved by closer communication between coders and clinicians. ORIGINALITY/VALUE: The paper identifies a flaw in the way clinical activity and productivity is assessed at present. This is fundamental to the process on which "payment by results" is based, and therefore must be addressed if trusts are to be financially successful.