Multimodal decoding of human liver regeneration

The liver has a unique ability to regenerate1,2; however, in the setting of acute liver failure (ALF), this regenerative capacity is often overwhelmed, leaving emergency liver transplantation as the only curative option3-5. Here, to advance understanding of human liver regeneration, we use paired single-nucleus RNA sequencing combined with spatial profiling of healthy and ALF explant human livers to generate a single-cell, pan-lineage atlas of human liver regeneration. We uncover a novel ANXA2+ migratory hepatocyte subpopulation, which emerges during human liver regeneration, and a corollary subpopulation in a mouse model of acetaminophen (APAP)-induced liver regeneration. Interrogation of necrotic wound closure and hepatocyte proliferation across multiple timepoints following APAP-induced liver injury in mice demonstrates that wound closure precedes hepatocyte proliferation. Four-dimensional intravital imaging of APAP-induced mouse liver injury identifies motile hepatocytes at the edge of the necrotic area, enabling collective migration of the hepatocyte sheet to effect wound closure. Depletion of hepatocyte ANXA2 reduces hepatocyte growth factor-induced human and mouse hepatocyte migration in vitro, and abrogates necrotic wound closure following APAP-induced mouse liver injury. Together, our work dissects unanticipated aspects of liver regeneration, demonstrating an uncoupling of wound closure and hepatocyte proliferation and uncovering a novel migratory hepatocyte subpopulation that mediates wound closure following liver injury. Therapies designed to promote rapid reconstitution of normal hepatic microarchitecture and reparation of the gut-liver barrier may advance new areas of therapeutic discovery in regenerative medicine.

Microsurgery in the Sickle Cell Trait Population: Can it Be Safely and Successfully Performed?

Free-tissue transfer reconstruction in patients with sickle cell anemia risks failure due to polymerization of sickle hemoglobin within the flap microcirculation. However, outcomes vary, as the amount of polymerization is dependent on factors such as disease phenotype/diagnosis, degree of hypoxia, and intracellular dehydration. Most of the literature focuses on patients with sickle cell disease, which produces higher concentrations of sickle hemoglobin and, therefore, is a contraindication to microvascular reconstruction. Fewer reports describe microsurgery in patients with sickle cell trait (SCT) who carry the heterozygous phenotype. Here, we present a case in which a patient with SCT underwent microsurgical breast reconstruction with deep inferior epigastric perforator free-tissue transfer. The 52-year-old woman had previously experienced a failed alloplastic-based reconstruction after radiation therapy for breast cancer. In our case, clinical and Doppler examinations demonstrated that arterial and venous anastomoses had remained patent; so the patient was discharged on postoperative day 4. Blistering developed on postoperative day 8, and by day 15 there was partial necrosis of the inferior-lateral aspect of the deep inferior epigastric perforator flap. Debridement and closure resolved the issue, and at 5 months postprocedure, the flap remained well-perfused and well-incorporated. This case, presented here with patient consent, reports a successful outcome of microsurgical reconstruction in a patient with SCT. It expands the limited evidence to support the safety and feasibility of autologous surgical interventions for patients with the heterozygous phenotype of sickle cell anemia.

Delayed Thoracodorsal Artery Perforator Free Flap for Calcaneal Degloving Injury Reconstruction

The thoracodorsal artery perforator (TDAP) flap has a long vascular pedicle that is ideal for lower extremity reconstruction, but it generally relies on the presence of a dominant septocutaneous perforator vessel. Surgical delay optimizes flap survival by creating relative ischemia to augment perforator vessels. In this report, we describe the use of a delayed free TDAP flap in the setting of an absent dominant perforator vessel for the reconstruction of a calcaneal degloving injury. A 22-year-old actively smoking patient with a body mass index of 33.5 presented with a nonhealing left heel wound with overlying necrotic changes after traumatic degloving injury. The entire weight-bearing portion of the calcaneal fat pad and the flanking regions were debrided. The TDAP flap was elevated, revealing three small thoracodorsal artery perforators. Given that a dominant perforator was absent, the flap was surgically delayed. Free-tissue transfer occurred 8 days later. This operation was conducted entirely in left lateral decubitus with simultaneous wound preparation and flap harvest. The flap was elevated on two perforators to elongate the pedicle's length and inset to cover exposed calcaneus and pad the heel. Six months postoperatively, the patient is doing well without flap compromise or ulceration. The TDAP flap is a versatile microsurgical tool, and surgical delay extends the utility of this flap when a dominant septocutaneous perforator is unavailable. Recipient site debridement may occur simultaneously with the TDAP delay procedure. Importantly, only one position is required for flap elevation, microsurgical anastomosis, and insetting, thus obviating intraoperative repositioning.

Abdominal Wall Reconstruction After Extirpation of a 140-Pound Primary Ovarian Mucinous Adenocarcinoma

Ovarian cancer is a feared diagnosis for women and clinicians alike. Ovarian mucinous adenocarcinoma is a unique subset of ovarian cancer. As a primary tumor, massive ovarian masses, and more specifically mucinous adenocarcinomas, have been infrequently reported in the medical literature. Team approaches to massive tumor extirpations are essential, as patients often require the expertise of various subspecialists including, but not limited to, gynecologic-oncologists, general surgeons, and plastic and reconstructive surgeons. Here we present a case of a 71-year-old woman with a massive, incapacitating pelvic mass, later found to be a primary ovarian mucinous adenocarcinoma. Once medically optimized, a multi-service team approach was utilized for tumor extirpation and abdominal wall reconstruction. Involved surgical services included Gynecologic-Oncology, General Surgery, and Plastic and Reconstructive Surgery. Exploratory laparotomy for tumor extirpation, hysterectomy, bilateral salpingo-oophorectomy, omentectomy, peritoneal stripping, bilateral inguinal lymphadenectomy, and appendectomy was performed. Extensively thin, devascularized, and attenuated abdominal wall fascia that was adherent to the tumor was removed. The abdominal wall defect was reconstructed and reinforced with inlay and overlays of biologic monofilament mesh. Inverted-T of the vertical and horizontal skin components was performed in a tailor-tacking fashion, assuring the maintenance and protection of the abdominal skin flap vascularity through utilizing the Huger Zones of perfusion. Pathology revealed a stage IA grade 2 mucinous adenocarcinoma of the ovary without evidence of metastasis. No adjuvant therapies were required. The tumor's weight was 140 pounds, and its dimensions were 63 x 41 x 40 cm. It is our hope that presenting this experience will raise awareness of this spectrum of diseases and allow for earlier diagnoses and treatments, as well as exemplify the virtues of a team-based approach in the successful extirpation and subsequent reconstruction of the abdominal wall and skin.

Primary Cutaneous Secretory Carcinoma: A Case Report and Literature Review

Cutaneous secretory carcinomas (CSCs) are primary neoplasms of the skin that have been just recently described in the literature through case reports and series. In this case, a cutaneous lesion was found on the left temporal region of an 83-year-old male. He was referred to plastic surgery for complete excision, with negative margins confirmed by pathology. Histology, immunostaining, and genetic testing showed characteristics confirming the diagnosis of CSC and were supported by the information present in the current literature. Our patient showed no evidence of nodal disease or recurrence during regular follow-ups. Given the rarity of CSCs, we aim to present our experience regarding the diagnosis, pathological analysis, and management of our patient as well as summarize the present literature to further open avenues of research.

Structural and functional spatial dynamics of microbial communities in aerated and non-aerated horizontal flow treatment wetlands

A multiphasic study using structural and functional analyses was employed to investigate the spatial dynamics of the microbial community within five horizontal subsurface flow treatment wetlands (TWs) of differing designs in Germany. The TWs differed in terms of the depth of media saturation, presence of plants (Phragmites australis), and aeration. In addition to influent and effluent water samples, internal samples were taken at different locations (12.5 %, 25 %, 50 %, and 75 % of the fractional distance along the flow path) within each system. 16S rRNA sequencing was used for the investigation of microbial community structure and was compared to microbial community function and enumeration data. The microbial community structure in the unaerated systems was similar, but different from the aerated TW profiles. Spatial positioning along the flow path explained the majority of microbial community dynamics/differences within this study. This was mainly attributed to the availability of nutrients closer to the inlet which also regulated the fixed biofilm/biomass densities. As the amount of fixed biofilm decreased from the inlet to the TW outlets, structural diversity increased, suggesting different microbial communities were present to handle the more easily utilized/degraded pollutants near the inlet vs. the more difficult to degrade and recalcitrant pollutants closer to the outlets. This study also confirmed that effluent water samples do not accurately describe the microbial communities responsible for water treatment inside a TW, highlighting the importance of using internal samples for investigating microbial communities in TWs. The results of this study reinforce an existing knowledge gap regarding the potential for TW design modifications which incorporate microbial community spatial dynamics (heterogeneity). It is suggested that utilizing step-feeding could allow for improved water treatment within the same areal footprint, and modifications enhancing co-metabolic processes could assist in improving the treatment of more difficult to degrade or recalcitrant compounds such as micropollutants.

Exploring dimensions of quality-of-life in survivors of stroke with communication disabilities - a brief report

BACKGROUND

People with communication disabilities post-stroke have poor quality-of-life.

OBJECTIVES

We aimed to explore the association of self-reported communication disabilities with different dimensions of quality-of-life between 90 and 180 days post-stroke.

METHODS

Cross-sectional survey data were obtained between 90 and 180 days post-stroke from registrants in the Australian Stroke Clinical Registry recruited from three hospitals in Queensland. The usual follow-up survey included the EQ5D-3L. Responses to the Hospital Anxiety and Depression Scale, and extra questions (e.g. communication disabilities) were also collected. We used χ² statistics to determine differences.

RESULTS

Overall, 244/647 survivors completed the survey. Respondents with communication disabilities (n = 72) more often reported moderate to extreme problems in all EQ5D-3L dimensions, than those without communication disabilities (n = 172): anxiety or depression (74% vs 40%, p < .001), pain or discomfort (58% vs 39%, p = .006), self-care (46% vs 18%, p < .001), usual activities (77% vs 49%, p < .001), and mobility (68% vs 35%, p < .001). Respondents with communication disabilities reported less fatigue (66% vs 89%, p < .001), poorer cognitive skills (thinking) (16% vs 1%, p < .001) and lower social participation (31% vs 6%, p < .001) than those without communication disabilities.

CONCLUSIONS

Survivors of stroke with communication disabilities are more negatively impacted across different dimensions of quality-of-life (as reported between 90 and 180 days post-stroke) compared to those without communication disabilities. This highlights the need for timely and on-going comprehensive multidisciplinary person-centered support.

Lower Extremity Soft Tissue Reconstruction Review Article

Reconstruction plays a valuable role in the management of lower extremity wounds for limb salvage. The goals of reconstruction are to improve function and quality of life, return to work, and pain reduction while providing a long-lasting durable reconstruction. The plastics and reconstructive surgical approach in conjunction with the orthopedic or trauma team, referred often as the "orthoplastic" approach, can yield the best outcomes for patients. The following sections discuss reconstruction principles and techniques that can be applied broadly for lower extremity wounds secondary to trauma, infection, and tumor resection.

Non-surgical Management of Complex Refractory Pyoderma Gangrenosum With Negative Pressure Wound Therapy With Instillation

Pyoderma gangrenosum (PG) is a rare skin disorder primarily treated with immunosuppression medication. We report a case of a large, chronic PG wound treated with adjunct negative pressure wound therapy with instillation and dwell time (NPWTi-d) using nonadherent dressing (Mepitel) and reticular open-cell foam with through holes (ROCF-CC) with positive outcomes. The patient was a 62-year-old female with rheumatoid arthritis, Hashimoto’s thyroiditis, lymphedema, and morbid obesity who presented with a 19.5 cm x 13.2 cm x 2.1 cm wound of three years duration on the right posterolateral lower extremity that successfully responded to a multimodality approach of immunosuppression and wound vac therapy. We conclude in our case that NPWTi-d with Mepitel and ROCF-CC enhanced the wound healing process, and we discuss NPWTi-d’s potential role and benefit as an adjunctive therapy option for chronic and poorly controlled PG on patients taking concurrent immunosuppression.

Isolated Scaphoid Dislocation From Low-Energy Wrist Trauma

Isolated scaphoid dislocation is an extremely rare injury typically caused by high-energy trauma. We present the first observed case of isolated scaphoid dislocation resulting from a non-traumatic injury of the wrist in power-grip tension in a patient with a questionable history of Marfan Syndrome. A 20-year-old right-hand dominant man presented to the emergency department with right wrist pain and deformation after carrying a table. The patient reported a possible history of Marfan Syndrome, but it had never been definitively diagnosed. Imaging revealed radial dislocation of the scaphoid. Bedside closed reduction was performed followed by outpatient ligament reconstruction with return to normal activities at 6 months. Early diagnosis and management lead to an improved prognosis for isolated scaphoid dislocation. Regardless of patient history or mechanism of injury, treatment options include closed reduction, percutaneous fixation, and/or open reduction with internal fixation and ligamentous reconstruction.

Use of Botulinum Toxin A to Treat Chemotherapy-Induced Raynaud's Phenomenon

Raynaud’s phenomenon (RP) is a vasospastic disorder of the digital blood vessels leading to pain, paresthesias, and pallor in response to cold or stress. RP can develop secondary to a number of pathologies or factors, including the use of chemotherapy agents. Typical first-line therapies for secondary RP may be contraindicated in patients with certain comorbidities. Here, we discuss a case in which botulinum toxin A (BTX-A) was used to treat chemotherapy-induced RP in a patient with non-small cell lung cancer (NSCLC). We provide a review of the existing literature on the clinical course and treatment modalities, including the use of BTX-A, for patients with secondary RP.

A 56-year-old female with NSCLC received treatment with bevacizumab and pemetrexed. Her initial symptoms included progressive discoloration and pain in her fingertips, which hastily progressed to ischemia and subsequent dry gangrene. She was diagnosed with chemotherapy-induced RP, but traditional management options were complicated by acute congestive heart failure. BTX-A injections were administered at key locations on the wrist and hand, significantly improving her symptoms and slowing the progression of the gangrenous changes.

RP can develop as sequelae of chemotherapy regimens. Clinical management may be complicated by underlying pathology and/or patient symptoms. BTX-A injections are an excellent non-operative therapeutic option for patients with secondary RP in cases where mainstay therapies may be contraindicated, thus decreasing pain, improving patient quality of life, and slowing the progression of gangrenous changes.

Pyoderma Gangrenosum after Fat Grafting in Alloplastic Breast Reconstruction: An Unusual Outcome

Pyoderma gangrenosum (PG) is a rare and painful inflammatory skin disorder that has been recently associated with breast surgery. It is commonly mistaken for postoperative ischemia or wound infection and does not show response to antibiotics or debridement. We describe the first case of post-surgical PG (PSPG) after alloplastic breast reconstruction involving fat grafting. A 47-year-old woman underwent bilateral mastectomy and 2-stage alloplastic breast reconstruction, with fat grafting from the abdomen. Two days post-surgery, she developed bilateral erythema with tender grouped pustules that progressed rapidly into necrotic ulcerations. She did not respond to antibiotics and serial debridement. Subsequent biopsy confirmed a diagnosis of PG. She was started on steroid therapy and responded well. She was discharged on a steroid regimen, local wound care, and eventually a T-cell inhibitor. Over the next 12 months, her wounds healed without surgical intervention. PSPG has been observed in a variety of reconstructive breast surgeries, but never reported in the setting of fat grafting. As PG involves subcutaneous fat, fat grafting may accelerate and exacerbate the course of disease. Treatment for PSPG includes systemic steroid therapy or other immunomodulatory agents (or both). Surgical management remains controversial, as serial debridement and reconstruction have shown to exacerbate and stimulate disease progression. A long-term follow-up is recommended to monitor for wound healing. Delayed diagnosis of PG in breast reconstruction patients can lead to severe morbidity and disfigurement. This is first case of PSPG following fat grafting in the literature.

Polycyclic aromatic compounds (PACs) in the Canadian environment: The challenges of ecological risk assessments

Ecological risk assessments (ERAs) of polycyclic aromatic compounds (PACs), as single congeners or in mixtures, present technical challenges that raise concerns about their accuracy and validity for Canadian environments. Of more than 100,000 possible PAC structures, the toxicity of fewer than 1% have been tested as individual compounds, limiting the assessment of complex mixtures. Because of the diversity in modes of PAC action, the additivity of mixtures cannot be assumed, and mixture compositions change rapidly with weathering. In vertebrates, PACs are rapidly oxygenated by cytochrome P450 enzymes, often to metabolites that are more toxic than the parent compound. The ability to predict the ecological fate, distribution and effects of PACs is limited by toxicity data derived from tests of a few responses with a limited array of test species, under optimal laboratory conditions. Although several models are available to predict PAC toxicity and rank species sensitivity, they were developed with data biased by test methods, and the reported toxicities of many PACs exceed their solubility limits. As a result, Canadian Environmental Quality Guidelines for a few individual PACs provide little support for ERAs of complex mixtures in emissions and at contaminated sites. These issues are illustrated by reviews of three case studies of PAC-contaminated sites relevant to Canadian ecosystems. Interactions among ecosystem characteristics, the behaviour, fate and distribution of PACs, and non-chemical stresses on PAC-exposed species prevented clear associations between cause and effect. The uncertainties of ERAs can only be reduced by estimating the toxicity of a wider array of PACs to species typical of Canada's diverse geography and environmental conditions. Improvements are needed to models that predict toxicity, and more field studies of contaminated sites in Canada are needed to understand the ecological effects of PAC mixtures.

Polycyclic aromatic compounds (PACs) in the Canadian environment: Exposure and effects on wildlife

Polycyclic aromatic compounds (PACs) are ubiquitous in the environment. Wildlife (including fish) are chronically exposed to PACs through air, water, sediment, soil, and/or dietary routes. Exposures are highest near industrial or urban sites, such as aluminum smelters and oil sands mines, or near natural sources such as forest fires. This review assesses the exposure and toxicity of PACs to wildlife, with a focus on the Canadian environment. Most published field studies measured PAC concentrations in tissues of invertebrates, fish, and birds, with fewer studies of amphibians and mammals. In general, PAC concentrations measured in Canadian wildlife tissues were under the benzo[a]pyrene (BaP) guideline for human consumption. Health effects of PAC exposure include embryotoxicity, deformities, cardiotoxicity, DNA damage, changes to DNA methylation, oxidative stress, endocrine disruption, and impaired reproduction. Much of the toxicity of PACs can be attributed to their bioavailability, and the extent to which certain PACs are transformed into more toxic metabolites by cytochrome P450 enzymes. As most mechanistic studies are limited to individual polycyclic aromatic hydrocarbons (PAHs), particularly BaP, research on other PACs and PAC-containing complex mixtures is required to understand the environmental significance of PAC exposure and toxicity. Additional work on responses to PACs in amphibians, reptiles, and semi-aquatic mammals, and development of molecular markers for early detection of biological responses to PACs would provide a stronger biological and ecological justification for regulating PAC emissions to protect Canadian wildlife.

Simultaneous Bilateral Patellar Tendon Rupture in a Young Adult Male: A Case Report and Review of the Literature

A bilateral patellar tendon rupture is extremely rare and has only been documented in case reports. Although the etiology remains unknown, predisposing factors include steroid usage, systemic diseases, and tendinopathies. In the present case, a healthy 33-year-old male with a prior history of bilateral patellar tendonitis and a diagnosis of Osgood-Schlatter disease during adolescence experienced simultaneous bilateral patellar tendon rupture after playing volleyball. He underwent bilateral patellar repair without complications. In the absence of trauma, spontaneous bilateral patellar tendon ruptures are associated with several predisposing factors, including systemic diseases, prior corticosteroid or fluoroquinolone usage, and history of tendinopathy. Injuries can be classified based on the location of the rupture. Bilateral patellar tendon ruptures can be misdiagnosed due to the rarity of cases and the lack of a normal comparative knee. Radiographic techniques can aid in the diagnosis, leading to early surgical treatment and improved outcomes. Early diagnosis and prompt surgical repair contribute to good functional outcomes in this potentially debilitating injury pattern.

Cutaneous Carcinosarcoma: A Small Case Series and Review of the Literature of a Rare Skin Tumor

Carcinosarcomas are composed of epithelial and mesenchymal elements and primarily present within visceral organs. Despite being potentially aggressive, they are a rare diagnosis in the skin, and few manifestations have been reported to date. In this report, we describe two separate cases of carcinosarcoma presenting as nonhealing scalp wounds. Patient A: a 57-year-old male with a nonhealing skin lesion of ten years successfully treated with wide-local excision and local ortichochea flap reconstruction. Patient B: a 75-year-old female that presented with a painless, slow-growing hemorrhagic mass of 7 years invading the skull and dura ultimately requiring craniectomy and free-tissue transfer with anterolateral thigh flap. Cutaneous carcinosarcomas have more favorable outcomes due to low metastatic rates likely due to earlier detection, but delayed presentation can be fatal. Histopathological analysis is critical for determining diagnosis and prognosis. Adequate reconstruction after wide base excision varies and follows the reconstructive ladder/elevator ranging from primary closure up through free-tissue transfer. With cutaneous manifestations of carcinosarcoma seldom reported in the literature, it is our hope that reporting unusual instances such as this will raise awareness and allow for earlier diagnoses, treatments, and reconstructions.

Sub-lethal effects of calcium dinonylnaphthalenesulfonate on Western clawed frog embryos

Naphthalene sulfonic acids (NSAs) are used as additives in lubricants, dyes, and greases and commonly act as surfactants in many industrial processes. The calcium salt of dinonyl NSA (calcium dinonylnaphthalenesulfonate; CaDNS) is listed among thousands of chemicals identified as priorities for assessment by the Government of Canada's Chemical Management Plan due to the limited toxicity data. The purpose of this study was two-fold: 1) to establish the toxicity of CaDNS to Western clawed frog (Silurana tropicalis) embryos and 2) to assess the sub-lethal effects and mechanisms of toxicity of CaDNS in amphibians through targeted gene expression and metabolite analyses. Frog embryos were exposed to water overlying sand spiked with a range of concentrations of CaDNS (17-1393 μg/g) over a 72-h period. Results indicated significantly higher mortality and presence of malformations in frog larvae exposed to over 672 μg/g CaDNS in the sand (14 ng/mL CaDNS in the water) compared to control treatments. An overall decrease in the glutathione redox cycle was observed, including decreases in relative mRNA levels of enzymes (glutathione S-transferase (gst), glutathione reductase (gsr), glutathione peroxidase (gpx)) and decreases in the glutathione (GSH) and glutathione disulfide (GSSG) metabolite concentrations. In addition, transcript levels of genes involved in antioxidant capacity and essential amino acid metabolites decreased significantly in embryos exposed to low levels of CaDNS. This is the first study to assess the toxicity of NSAs in amphibians, contributing important data to aid in the assessment of NSAs.

Hepatitis E: a largely underestimated, emerging threat

Hepatitis E virus has two distinct clinical and epidemiological patterns based on the varying genotypes. Genotypes 3 and 4 cause widespread, sporadic infection in high-income countries and are emerging as the most common type of viral hepatitis in much of Europe. These infections carry significant morbidity and mortality in the growing numbers of immunosuppressed patients or in patients with established liver disease. Furthermore the growing extra-hepatic associations of the virus, including neurological and kidney injury, suggest that it may have been misnamed as a 'hepatitis' virus. This review explores current understanding of the epidemiology, virology and clinical presentations of hepatitis E infection and identifies vulnerable patient groups, who are at serious risk from infection. Guidance is offered regarding the diagnosis, treatment and prevention of this growing public health hazard.

Airborne polycyclic aromatic compounds contribute to the induction of the tumour-suppressing P53 pathway in wild double-crested cormorants

Polycyclic aromatic compounds (PACs), including polycyclic aromatic hydrocarbons (PAHs) and PAH-like compounds are known or probable environmental carcinogens released into the environment as a by-product of incomplete combustion of fossil fuels and other organic materials. Studies have shown that exposure to PACs in the environment can induce both genotoxicity and epigenetic toxicity, but few studies have related PAC exposure to molecular changes in free ranging wildlife. Previous work has suggested that double-crested cormorants (Phalacrocorax auritus; DCCO) exhibited a higher incidence of genetic mutations when their breeding sites were located in heavily industrialized areas (e.g., Hamilton Harbour, Hamilton, ON, Canada) as compared to sites located in more pristine environments, such as in Lake Erie. The aim of this study was to determine if airborne PACs from Hamilton Harbour alter the tumour-suppressing P53 pathway and/or global DNA methylation in DCCOs. Airborne PACs were measured using passive air samplers in the Hamilton Harbour area and low-resolution mass spectrometry analysis detected PACs in livers of DCCOs living in Hamilton Harbour. Further hepatic and lung transcriptional analysis demonstrated that the expression of the genes involved in the DNA repair and cellular apoptosis pathway were up-regulated in both tissues of DCCOs exposed to PACs, while genes involved in p53 regulation were down-regulated. However, global methylation levels did not differ between reference- and PAC-exposed DCCOs. Altogether, data suggest that PACs activate the P53 pathway in free-ranging DCCOs living nearby PAC-contaminated areas.

A phylogenetic test of sympatric speciation in the Hydrobatinae (Aves: Procellariiformes)

Phylogenetic relationships among species can provide insight into how new species arise. For example, careful consideration of both the phylogenetic and geographic distributions of species in a group can reveal the geographic models of speciation within the group. One such model, sympatric speciation, may be more common than previously thought. The Hydrobatinae (Aves: Procellariformes) is a diverse subfamily of Northern Hemisphere storm-petrels for which the taxonomy is unclear. Previous studies showed that Hydrobates (formally Oceanodroma) castro breeding in the Azores during the cool season is sister species to H. monteiroi, a hot season breeder at the same locations, which suggests sympatric speciation by allochrony. To test whether other species within the subfamily arose via sympatric speciation by allochrony, we sequenced the cytochrome b gene and five nuclear introns to estimate a phylogenetic tree using multispecies coalescent methods, and to test whether species breeding in the same geographic area are monophyletic. We found that speciation within the Hydrobatinae appears to have followed several geographic modes of divergence. Sympatric seasonal species in Japan likely did not arise through sympatric speciation, but allochrony may have played a role in the divergence of H. matsudairae, a cool season breeder, and H. monorhis, a hot season breeder. No other potential cases of sympatric speciation were discovered within the subfamily. Despite breeding in the same geographic area, hydrobatine storm-petrels breeding in Baja California (H. microsoma and H. melania) are each sister to a species breeding off the coast of Peru (H. tethys and H. markhami, respectively). In fact, antitropical sister species appear to have diverged at multiple times, suggesting allochronic divergence might be common. In addition, allopatry has likely played a role in divergence of H. furcata, a north Pacific breeder, and H. pelagius, a north Atlantic breeder. This study demonstrates that a variety of mechanisms of divergence have played a role in generating the diversity of the Hydrobatinae and supports the current taxonomy of the subfamily.

Injury Risk Estimation Expertise: Assessing the ACL Injury Risk Estimation Quiz

BACKGROUND

Available methods for screening anterior cruciate ligament (ACL) injury risk are effective but limited in application as they generally rely on expensive and time-consuming biomechanical movement analysis. A potentially efficient alternative to biomechanical screening is skilled movement analysis via visual inspection (ie, having experts estimate injury risk factors based on observations of athletes' movements).

PURPOSE

To develop a brief, valid psychometric assessment of ACL injury risk factor estimation skill: the ACL Injury Risk Estimation Quiz (ACL-IQ).

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

A total of 660 individuals participated in various stages of the study, including athletes, physicians, physical therapists, athletic trainers, exercise science researchers/students, and members of the general public in the United States. The ACL-IQ was fully computerized and made available online (www.ACL-IQ.org). Item sampling/reduction, reliability analysis, cross-validation, and convergent/discriminant validity analyses were conducted to refine the efficiency and validity of the assessment.

RESULTS

Psychometric optimization techniques identified a short (mean time, 2 min 24 s), robust, 5-item assessment with high reliability (test-retest: r = 0.90) and high test sensitivity (average difference of exercise science professionals vs general population: Cohen d = 2). Exercise science professionals and individuals from the general population scored 74% and 53% correct, respectively. Convergent and discriminant validity was demonstrated. Scores on the ACL-IQ were best predicted by ACL knowledge and specific judgment strategies (ie, cue use) and were largely unrelated to domain-general spatial/decision-making ability, personality, or other demographic variables. Overall, 23% of the total sample (40% of exercise science professionals; 6% of general population) performed better than or equal to the ACL nomogram.

CONCLUSION

This study presents the results of a systematic approach to assess individual differences in ACL injury risk factor estimation skill; the assessment approach is efficient (ie, it can be completed in <3 min) and psychometrically robust. The results provide evidence that some individuals have the ability to visually estimate ACL injury risk factors more accurately than other instrument-based ACL risk estimation methods (ie, ACL nomogram). The ACL-IQ provides the foundation for assessing the efficacy of observational ACL injury risk factor assessment (ie, does simple skilled visual inspection reduce ACL injuries?). The ACL-IQ can also be used to increase our understanding of the perceptual-cognitive mechanisms underlying injury risk assessment expertise, which can be leveraged to accelerate learning and improve performance.

Elevated CDCP1 predicts poor patient outcome and mediates ovarian clear cell carcinoma by promoting tumor spheroid formation, cell migration and chemoresistance

Hematogenous metastases are rarely present at diagnosis of ovarian clear cell carcinoma (OCC). Instead dissemination of these tumors is characteristically via direct extension of the primary tumor into nearby organs and the spread of exfoliated tumor cells throughout the peritoneum, initially via the peritoneal fluid, and later via ascites that accumulates as a result of disruption of the lymphatic system. The molecular mechanisms orchestrating these processes are uncertain. In particular, the signaling pathways used by malignant cells to survive the stresses of anchorage-free growth in peritoneal fluid and ascites, and to colonize remote sites, are poorly defined. We demonstrate that the transmembrane glycoprotein CUB-domain-containing protein 1 (CDCP1) has important and inhibitable roles in these processes. In vitro assays indicate that CDCP1 mediates formation and survival of OCC spheroids, as well as cell migration and chemoresistance. Disruption of CDCP1 via silencing and antibody-mediated inhibition markedly reduce the ability of TOV21G OCC cells to form intraperitoneal tumors and induce accumulation of ascites in mice. Mechanistically our data suggest that CDCP1 effects are mediated via a novel mechanism of protein kinase B (Akt) activation. Immunohistochemical analysis also suggested that CDCP1 is functionally important in OCC, with its expression elevated in 90% of 198 OCC tumors and increased CDCP1 expression correlating with poor patient disease-free and overall survival. This analysis also showed that CDCP1 is largely restricted to the surface of malignant cells where it is accessible to therapeutic antibodies. Importantly, antibody-mediated blockade of CDCP1 in vivo significantly increased the anti-tumor efficacy of carboplatin, the chemotherapy most commonly used to treat OCC. In summary, our data indicate that CDCP1 is important in the progression of OCC and that targeting pathways mediated by this protein may be useful for the management of OCC, potentially in combination with chemotherapies and agents targeting the Akt pathway.

EGF inhibits constitutive internalization and palmitoylation-dependent degradation of membrane-spanning procancer CDCP1 promoting its availability on the cell surface

Many cancers are dependent on inappropriate activation of epidermal growth factor receptor (EGFR), and drugs targeting this receptor can improve patient survival, although benefits are generally short-lived. We reveal a novel mechanism linking EGFR and the membrane-spanning, cancer-promoting protein CDCP1 (CUB domain-containing protein 1). Under basal conditions, cell surface CDCP1 constitutively internalizes and undergoes palmitoylation-dependent degradation by a mechanism in which it is palmitoylated in at least one of its four cytoplasmic cysteines. This mechanism is functional in vivo as CDCP1 is elevated and palmitoylated in high-grade serous ovarian tumors. Interestingly, activation of the EGFR system with EGF inhibits proteasome-mediated, palmitoylation-dependent degradation of CDCP1, promoting recycling of CDCP1 to the cell surface where it is available to mediate its procancer effects. We also show that mechanisms inducing relocalization of CDCP1 to the cell surface, including disruption of its palmitoylation and EGF treatment, promote cell migration. Our data provide the first evidence that the EGFR system can function to increase the lifespan of a protein and also promote its recycling to the cell surface. This information may be useful for understanding mechanisms of resistance to EGFR therapies and assist in the design of treatments for EGFR-dependent cancers.

Implementation of the Connective Tissue Screening Questionnaire in northeast Pennsylvania to identify comorbidities of connective tissue diseases in subjects with systemic lupus erythematosus

Previous studies have described an increased risk of developing an additional connective tissue disease (CTD) when one such ailment is present. We examine here the likelihood that individuals with systemic lupus erythematosus (SLE) screen positive for one or more of the following five autoimmune CTDs: Sjögren's syndrome, scleroderma, rheumatoid arthritis, dermatomyositis/polymyositis, and mixed connective tissue disorder. Five hundred SLE-diagnosed subjects were asked to complete a CTD screening questionnaire (CSQ). The results were analyzed according to the set of diagnostic criteria given by the American College of Rheumatology to identify probable cases of each CTD. Significant standardized prevalence ratios and comorbidities indicate an increased risk for the other autoimmune CTDs. In all, 96% of the subjects screened positive for at least one additional CTD, and 13% screened positive for at least two additional CTDs. We see that the SLE-diagnosed population may benefit from further attention regarding the presence of additional CTDs, which may further inform treatment strategies. We also see the application of the CSQ as a potentially important tool for clinical practice, and we describe the present study's limitations along with possible ways that these can be addressed.

Newer antiepileptic drugs: advantages and disadvantages

The choice of an antiepileptic drug depends firstly on its efficacy in specific seizure types and epilepsies. However, it is imperative to consider whether possible adverse events will outweigh any benefits. The advantages and disadvantages of vigabatrin, lamotrigine, gabapentin, topiramate, tiagabine and felbamate are considered in some detail, and oxcarbazepine, stiripentol, remacemide, zonisamide and levetiracetam more briefly. Vigabatrin is effective for partial seizures and infantile spasms, but visual field defects are limiting its use. Lamotrigine has a wide spectrum, needs to be prescribed with care. Gabapentin is unlikely to cause adverse effects, but has relatively poor efficacy. Topiramate is widely effective, but can be poorly tolerated. Tiagabine is relatively untried in childhood epilepsies. The use of felbamate is restricted to severe refractory epilepsies. Stiripentol can be effective in severe myoclonic epilepsy in infancy. Zonisamide has a special place in the progressive myoclonus epilepsies. Levetiracetam, remacemide and oxcarbazepine have been used mainly for partial seizures: further studies of their roles in other circumstances are required.

Influence of supplementary fibrolytic enzymes on the fermentation of corn and grass silages by mixed ruminal microorganisms in vitro

This study was done to determine the effectiveness of supplementary enzymes at increasing the fiber digestion by ruminal microorganisms and to assess whether enzyme activity limits the rate of fiber digestion in ruminal digesta. In vitro comparisons of enzyme activities in two feed enzyme preparations (A and B) with enzyme activities extracted from ruminal fluid indicated that the addition of fibrolytic enzymes at the application rates recommended by the manufacturers would not be expected to increase significantly glycanase and polysaccharidase activities in ruminal fluid. Preparations A and B both increased (P < 0.001) the rate of gas production from freeze-dried corn and grass silages in in vitro incubations with ruminal fluid, but only at concentrations much higher than recommended application rates. Autoclaved controls had little or no effect. Ultrafiltration of enzyme B indicated that most stimulation was due to components >100 kDa, which is consistent with the cause of the stimulation being enzyme activity. Fibrolytic enzymes from other sources were also able to stimulate gas production: increased rates of gas production were observed in seven out of eight combinations of "cellulase" and corn or grass silage (P < 0.05). The comparison of glycanase and polysaccharidase activities with gas-stimulatory activity in the different enzyme preparations indicated that the highest correlation was between increased gas production and enzyme activity against microgranular cellulose (P < 0.05). In a wider range of fibrolytic enzyme preparations, those with endo-(beta-1,4)- or exo-(beta-1,4)-xylanase activity equal to that of preparation A did not produce similar increased rates of fermentation of corn silage when glucanase activity was low (P > 0.05). In contrast, preparations with glucanase activity similar to enzyme A gave at least as great (P < 0.05) an improvement in gas production than enzyme A, irrespective of xylanase activity. It was concluded that enzyme activity, probably a type of endo-(beta-1,4)-glucanase activity, limits the rate of fermentation of corn and grass silage in the rumen. Enzyme supplements of the type used in these experiments are unlikely to possess sufficient activity to overcome this limitation by direct application to ruminal digesta, implying that treatment of the ration prefeeding will be key to harnessing the potential of exogenous fibrolytic enzymes in ruminant nutrition.

Proteolytic activity of ruminal digesta during the feeding cycle in sheep receiving grass hay/concentrate or maize silage/concentrate diets

Proteolytic activity was measured by the digestion of 14C-labelled casein in digesta removed from the rumen of four sheep receiving a grass hay/concentrate diet and four sheep receiving a maize silage/concentrate diet. Samples were removed immediately before feeding and at 2-h intervals after feeding up to 12 h. Animals on both diets produced similar proteolytic activities (1.83 (S.D. 0.41) and 2.14 (S.D. 0.61) mg 14C-casein hydrolysed (ml ruminal fluid)-1 h-1 with the maize silage- and grass hay-based diets, respectively). Time after feeding had no effect on proteolytic activity, but between-animal variation was consistent and highly significant, with the highest-activity animals having activities 64 and 74% higher than the lowest-activity animals on the two diets, respectively.

Epilepsy--a guide to medical treatment. 2: Non-drug aspects

Approximately 30-40% of people with epilepsy continue to have seizures despite drug treatment. Factors related to cognitive abilities, physical handicap, psychiatric illness and social circumstances are of great importance in the overall management.

Epilepsy--a guide to medical treatment. 1: Antiepileptic drugs

The epilepsies are the commonest of serious disorders of brain function. Medical, psychological, social and financial implications can adversely affect quality of life in both patient and family. Accurate categorization of seizure type and epilepsy syndrome, with appropriate choice of drug and other management, can minimize the burden of a seizure disorder.

Myoclonus and epilepsy in childhood: a review of treatment with valproate, ethosuximide, lamotrigine and zonisamide

Based on small numbers of patients, it is possible to make the following suggestions rather than categorical statements. For myoclonic seizures and epilepsies which are not otherwise specified, valproate seems of proven efficacy. Ethosuximide may be a useful adjunct. The exact place of lamotrigine, which controls some myoclonia and makes them worse in other patients, requires further study. The findings are clearer when specific syndromes are considered. Valproate is the treatment of first choice for benign myoclonic epilepsy in infants, myoclonic astatic epilepsy, epilepsy with myoclonic absences, eyelid myoclonia with absences, juvenile myoclonic epilepsy and progressive myoclonus epilepsy. The addition of ethosuximide to valproate can be helpful to those with myoclonic absences, where this combination appears more beneficial than either valproate or ethosuximide alone and in eyelid myoclonia with absences. Lamotrigine can be effective therapy for juvenile myoclonic epilepsy and eyelid myoclonia with absences when used alone and, in conjunction with other antiepileptic drugs (AED) (usually valproate) for early myoclonic encephalopathy, myoclonic-astatic epilepsy and particularly, epilepsy with myoclonic absences. The myoclonia of infantile neuronal ceroid lipofuscinosis respond to lamotrigine. Severe myoclonic epilepsy of infants usually worsens with lamotrigine, but occasionally, children improve. Zonisamide added to clonazepam and valproate or a barbiturate, can reduce the cascade of myoclonia in progressive myoclonus epilepsies for at least 2 years, but relapse may occur thereafter.

A survey of lamotrigine and vigabatrin treatment in children with severe epilepsy

A retrospective survey was carried out of add-on treatment with lamotrigine (LTG) and vigabatrin (GVG) in 109 children with severe epilepsy, treated between 1987 and 1994, identified from a total population of 300 patients seen annually, in a tertiary referral outpatient clinic in Cardiff, Wales. Of 79 patient treatments with LTG and 86 with GVG, 42 patients were treated with add-on LTG, 52 with add-on GVG and 20 with both drugs simultaneously. A Kaplan-Meier curve, applied to each of the two index drugs, indicated that 71 and 62% of patients would be expected to continue taking LTG or GVG, respectively after 40 months. Improved seizure control (> or = 50%) at the time of audit was seen in 65% of LTG and 58% of GVG patient treatments for all epilepsy syndromes, but there was a higher proportion of patients with generalized epilepsy improved by LTG (28/41, 68%) than that improved by GVG (8/20, 40%), and only those with generalized epilepsy treated with LTG became seizure free (8/38, 21%). Similar proportions of patients discontinued LTG (16%) and GVG (15%) due to an adverse experience, but a higher proportion discontinued GVG (18%) compared with LTG (6%) because of lack of efficacy. This study supports the relative clinical effectiveness of LTG and GVG in the real world, where children with severe epilepsy are treated in clinical practice and serves to generate hypotheses to enable design of prospectively controlled trials, which should enable more rational use of these two drugs in the paediatric population with epilepsy.

A comparative review of the adverse effects of anticonvulsants in children with epilepsy

Phenobarbital (phenobarbitone) and phenytoin are the most useful anticonvulsants in neonates because adverse effects are most readily reversed when these drugs are used. Most anticonvulsants are very rarely associated with haematological adverse effects. Platelet function is particularly vulnerable to valproic acid (sodium valproate) therapy. Barbiturates and phenytoin can precipitate metabolic bone disease. Although very infrequent, lymphadenopathy is most common with phenytoin, and lupus-like illnesses with ethosuximide. Valproic acid may precipitate underlying metabolic disorders. Nephrolithiasis can occur with topiramate. Liver disease is most likely with felbamate or valproic acid, but can occur with other anticonvulsants. Valproic acid and ethosuximide are the main precipitants of gastrointestinal symptomatology; while valproic acid and vigabatrin are frequently associated with excessive bodyweight gain. Rash is most likely to occur with barbiturates, but there is a high risk of this adverse effect if large doses of lamotrigine are given with valproic acid. Adverse cosmetic effects are most likely with phenytoin, but valproic acid may cause alopecia. All anticonvulsants may cause unwanted neurological effects: when they occur, diplopia is usually precipitated by carbamazepine; tremor by valproic acid; and other motor disturbances are probably most common with phenytoin. Most anticonvulsants can cause drowsiness. Phenobarbital leads anticonvulsants as a cause of behavioural difficulties. Effects of anticonvulsants on cognitive function are difficult to assess, but subtle changes have been reported for all anticonvulsants in use up to the 1980s. Compared with other anticonvulsant drugs, phenytoin and felbamate are more often discontinued as a result of unwanted effects.

Lamotrigine for the treatment of epilepsy in childhood

OBJECTIVE

In this multicenter study, the efficacy and tolerability of lamotrigine were assessed in 285 children less than 13 years of age, recruited from 37 centers in 11 countries.

METHODS

Pooled data from five open add-on studies have been analyzed. All the children had treatment-resistant epilepsy and most had two or more seizure types. Seizure frequency and global evaluation were assessed at the end of four successive 12-week periods of therapy.

RESULTS

Seizure frequency was reduced by 50% or more in one third of the patients. Lamotrigine was effective in all seizure types examined, particularly for typical and atypical absence seizures. Atonic seizures also responded well. Improvement was well maintained during the treatment period. The maintenance dose had to be adjusted according to concomitant medication; dose ranges were 1 to 5 mg/kg per day for children taking valproate and 5 to 15 mg/kg per day for those not taking valproate. The commonest reported adverse experiences were somnolence, rash, vomiting, and seizure exacerbations. Adverse experiences led to withdrawal of treatment from 36 patients (12.6%).

CONCLUSIONS

These results indicate that lamotrigine is well tolerated and is effective for a broad range of seizure types, especially absence seizures and atonic seizures.

Intracranial tumours during the first two years of life: presenting features

Between 1979 and 1994, 21 children (nine females, 12 males) with intracranial tumours diagnosed before the age of 2 years (range 2-23 months) were treated at the University Hospital of Wales. The commonest presenting symptoms were vomiting (n = 9) and unsteadiness (n = 8); the commonest presenting sign was enlarged occipitofrontal circumference (> 97th centile in 16 and > 90th centile in a further two). In five cases with signs of raised intracranial pressure, meningitis was the clinical diagnosis, and a lumbar puncture was performed. For cases with long delays in diagnosis, multiple other disorders had been considered and the significance of head enlargement had not been recognised. In very early childhood, intracranial tumours are uncommon and can mimic other disorders, especially meningitis. Early neuroimaging is advised when a child presents with recent onset of neurological symptoms and a disproportionately large head.

Management issues in severe childhood epilepsies

The severe epilepsies of childhood are described briefly and information available on the efficacy of newly developed antiepileptic drugs (AEDs) in their control is reviewed. Therapeutic advances are awaited for early infantile epileptic encephalopathy, early myoclonic encephalopathy, progressive myoclonus epilepsies and Kojewnikow syndrome. West syndrome may respond to vigabatrin, and less predictably to lamotrigine. Lamotrigine can be helpful for severe myoclonic epilepsy and myoclonic absences. Astatic seizures may be dramatically controlled by lamotrigine, whereas vigabatrin may worsen myoclonic attacks. In the Lennox-Gastaut syndrome, the efficacy of felbamate has been demonstrated by a controlled trial; vigabatrin and lamotrigine can also be helpful. Non-idiopathic partial and secondary generalized epilepsies are responsive to vigabatrin in a useful percentage of cases, and some children improve with felbamate, lamotrigine or striripentol. A trial which compares the efficacies of the newer AEDs against each other could provide very useful information for the clinician.

Convulsive status epilepticus in children treated for epilepsy: an assessment of management

The acute care and further management plans accorded to eight children, all already on treatment for epilepsy, admitted to hospital with a total of 17 episodes of convulsive status epilepticus were examined. Emergency treatment was appropriate, but longer-term management tended to be less than adequate. The causes of status epilepticus were not considered before discharge on 10 occasions. Advice on simple preventative measures was rarely given to the parents. Junior staff require further training in these areas.

Lamotrigine--a clinical overview

Data from five almost identical protocols have been pooled to give the results of treatment with lamotrigine in 285 children with refractory epilepsy. All the children received lamotrigine as open, add-on therapy and efficacy was assessed after the first 12 weeks of maintenance dosage. More than 50% reduction in seizures was achieved for over 30% of patients with complex partial, secondary generalized tonic-clonic, myoclonic, primary generalized tonic-clonic and atonic seizures; and, more than 50% of those with typical or atypical absences. In children treated for more than a year, there was no evidence of development of tolerance. Evaluations by investigators and parents found lamotrigine to improve the child globally in 74% of cases. Lamotrigine was well tolerated. Dizziness, unsteadiness and other non-specific side-effects that have been noted in a small minority of adults were rarely complained of by children. Rash was the most frequently reported side effect, leading to withdrawal of the drug in 7.4% of patients. However, the rate was lower when lamotrigine dosage was increased slowly as recommended. Data from other, smaller trials have also been reviewed and it is concluded that lamotrigine is a very well tolerated drug with a broad spectrum of efficacy.

Practical problems of epilepsy management in children

The problems associated with the investigation, diagnosis and treatment of epilepsy in children are considered in this paper, together with aspects of intellectual development. In addition, the difficulties encountered in family and school environments are reviewed. The problems which arise when medication is discontinued, and the possible importance of the loss, as well as the acquisition, of a condition, are also discussed.