Modulation of basal cell fate during productive and transforming HPV-16 infection is mediated by progressive E6-driven depletion of Notch.

In stratified epithelia such as the epidermis, homeostasis is maintained by the proliferation of cells in the lower epithelial layers and the concomitant loss of differentiated cells from the epithelial surface. These differentiating keratinocytes progressively stratify and form a self-regenerating multi-layered barrier that protects the underlying dermis. In such tissue, the continual loss and replacement of differentiated cells also limits the accumulation of oncogenic mutations within the tissue. Inactivating mutations in key driver genes, such as TP53 and NOTCH1, reduce the proportion of differentiating cells allowing for the long-term persistence of expanding mutant clones in the tissue. Here we show that through the expression of E6, HPV-16 prevents the early fate commitment of human keratinocytes towards differentiation and confers a strong growth advantage to human keratinocytes. When E6 is expressed either alone or with E7, it promotes keratinocyte proliferation at high cell densities, through the combined inactivation of p53 and Notch1. In organotypic raft culture, the activity of E6 is restricted to the basal layer of the epithelium and is enhanced during the progression from productive to abortive or transforming HPV-16 infection. Consistent with this, the expression of p53 and cleaved Notch1 becomes progressively more disrupted, and is associated with increased basal cell density and reduced commitment to differentiation. The expression of cleaved Notch1 is similarly disrupted also in HPV-16-positive cervical lesions, depending on neoplastic grade. When taken together, these data depict an important role of high-risk E6 in promoting the persistence of infected keratinocytes in the basal and parabasal layers through the inactivation of gene products that are commonly mutated in non-HPV-associated neoplastic squamous epithelia. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Death and Cardiac Arrest in U.S. Triathlon Participants, 1985 to 2016: A Case Series.

BACKGROUND: Reports of race-related triathlon fatalities have raised questions regarding athlete safety. OBJECTIVE: To describe death and cardiac arrest among triathlon participants. DESIGN: Case series. SETTING: United States. PARTICIPANTS: Participants in U.S. triathlon races from 1985 to 2016. MEASUREMENTS: Data on deaths and cardiac arrests were assembled from such sources as the U.S. National Registry of Sudden Death in Athletes (which uses news media, Internet searches, LexisNexis archival databases, and news clipping services) and USA Triathlon (USAT) records. Incidence of death or cardiac arrest in USAT-sanctioned races from 2006 to 2016 was calculated. RESULTS: A total of 135 sudden deaths, resuscitated cardiac arrests, and trauma-related deaths were compiled; mean (±SE) age of victims was 46.7 ± 12.4 years, and 85% were male. Most sudden deaths and cardiac arrests occurred in the swim segment (n = 90); the others occurred during bicycling (n = 7), running (n = 15), and postrace recovery (n = 8). Fifteen trauma-related deaths occurred during the bike segment. Incidence of death or cardiac arrest among USAT participants (n = 4 776 443) was 1.74 per 100 000 (2.40 in men and 0.74 in women per 100 000; P < 0.001). In men, risk increased substantially with age and was much greater for those aged 60 years and older (18.6 per 100 000 participants). Death or cardiac arrest risk was similar for short, intermediate, and long races (1.61 vs. 1.41 vs. 1.92 per 100 000 participants). At autopsy, 27 of 61 decedents (44%) had clinically relevant cardiovascular abnormalities, most frequently atherosclerotic coronary disease or cardiomyopathy. LIMITATIONS: Case identification may be incomplete and may underestimate events, particularly in the early study period. In addition, prerace medical history is unknown in most cases. CONCLUSION: Deaths and cardiac arrests during the triathlon are not rare; most have occurred in middle-aged and older men. Most sudden deaths in triathletes happened during the swim segment, and clinically silent cardiovascular disease was present in an unexpected proportion of decedents. PRIMARY FUNDING SOURCE: Minneapolis Heart Institute Foundation.

Hyperbaric oxygen treatment outcome for different indications from a single center.

BACKGROUND: Hyperbaric oxygen (HBO) is used as an adjunctive therapy for a variety of indications. However, there is a lack of high-quality research evaluating HBO treatment outcomes for different indications available in the current literature. METHODS: We retrospectively reviewed all patients who underwent HBO therapy at a single hyperbaric center from January 2010 to December 2013 using predetermined criteria to analyze successful, improved, or failed treatment outcomes for the following indications: chronic refractory osteomyelitis, diabetic foot ulcer, failed flap or skin graft, osteoradionecrosis, soft tissue radiation necrosis, and multiple coexisting indications. RESULTS: Among the included 181 patients treated with adjunctive HBO at our center, 81.8% had either successful or improved treatment outcomes. A successful or improved outcome was observed in 82.6% of patients treated for chronic refractory osteomyelitis (n = 23), 74.1% for diabetic foot ulcer (n = 27), 75.7% for failed flap or skin graft (n = 33), 95.7% for osteoradionecrosis (n = 23), 88.1% for soft tissue radiation necrosis (n = 42), and 72.4% for multiple coexisting indications (n = 29). Among 4 patients treated for other indications, 100% of the cases were either successful or improved. CONCLUSIONS: This study has provided a comprehensive outcome survey of using HBO for the previously mentioned indications at our center. It supplements the literature with more evidence to support the consideration of HBO in different indications.

Heavy Menstrual Bleeding in Adolescents with Joint Hypermobility Syndrome/Hypermobile-Type Ehlers-Danlos: A Review.

Heavy menstrual bleeding has a high prevalence and is well documented in adult patients with hypermobile-type Ehlers-Danlos syndrome, but there is limited research surrounding work-up and treatment for the adolescent population. Excessive menstrual blood loss can significantly interfere with emotional and physical quality of life. A provider should acquire a comprehensive medical and menstrual history and focused physical examination, as well as baseline laboratory studies, to determine the presence of anemia or underlying bleeding disorder. Use of a pictorial blood assessment chart may be considered to help quantify the amount of bleeding. Treatment to reduce heavy menstrual flow and referral to specialty care should be initiated swiftly to improve quality of life for this population. [Pediatr Ann. 2024;53(3):e104-e108.].

Phosphorylation of the human papillomavirus type 16 E1--E4 protein at T57 by ERK triggers a structural change that enhances keratin binding and protein stability.

The E1--E4 protein of human papillomavirus type 16 (HPV16) causes cytokeratin reorganization in the middle and upper epithelial layers and is thought to contribute to multiple facets of the virus life cycle. Although little is known as to how HPV16 E1--E4 (16E1--E4) functions are controlled following the first expression of this protein, the finding that low-risk E1--E4 proteins can be phosphorylated in vivo suggests an important role for kinases. Here, we show that 16E1--E4 is phosphorylated by cyclin-dependent kinase 1 (CDK1) and CDK2, extracellular signal-regulated kinase (ERK), protein kinase A (PKA), and PKC alpha, with CDK1/2 serine 32 and ERK threonine 57 phosphorylations representing the two primary events seen in cells in cycle. Interestingly, T57 phosphorylation was found to trigger a structural change in the 16E1--E4 protein that compacts the central fold region, leading to an increase in 16E1--E4 stability and overall abundance in the cell. When compared to wild-type 16E1--E4, a T57D phosphomimic was found to have greatly enhanced keratin-binding ability and an ability to modulate the binding of the unphosphorylated form, with keratin binding protecting the T57-phosphorylated form of 16E1--E4 from proteasomal degradation. In HPV16 genome-containing organotypic rafts, the T57-phosphorylated form was specifically detected in the intermediate cell layers, where productive infection occurs, suggesting that T57 phosphorylation may have a functional role at this stage of the viral life cycle. Interestingly, coexpression with 16E5 and ERK activation enhanced T57 phosphorylation, suggesting that E1--E4 and E5 may work together in vivo. Our data suggest a model in which the expression of 16E5 from the major E1--E4-E5 mRNA promotes T57 phosphorylation of E1--E4 and keratin binding, with dephosphorylation occurring following the switch to late poly(A) usage. Other forms of E1--E4, with alternative functional roles, may then increase in prevalence in the upper layers of the epithelium.

Mitral Valve Surgery in Neonates, Infants, and Children: Surgical Approach, Outcomes, and Predictors.

The surgical treatment of mitral disease in pediatrics is challenging. Managing diversity in patient anatomy, growth, and the need for long-term anticoagulation requires trade-offs between imperfect solutions. We sought to assess our approach to pediatric mitral valve surgery and identify predictors associated with mortality and recurrent mitral disease. The medical records, echocardiograms, and operative reports of all patients who underwent surgical intervention on the mitral valve from January 2000 to April 2016 were reviewed. A total of 143 patients underwent mitral valve surgery, 64 of which were neonates or infants (ages 10-355 days) and 79 of which were children (ages 1-17.8 years). Neonates and infants had a higher preoperative New York Heart Association heart failure classification in comparison to children (P < 0.001) with a less severe degree of mitral valve insufficiency (P = 0.007). Postoperative outcomes for primary repair patients (n = 133) demonstrated significant differences in recurrence of mitral valve disease, with 38% of neonates/infants and 21% of children affected (P = 0.028). Five-year rates of mortality or transplant were 22% (8%, 33%) in neonates and infants compared to 4% (0%, 10%) in children, P = 0.013. Mitral valve surgery in neonates and infants is particularly high risk and is associated with higher rate of recurrence and reintervention early. However, if successful early, mitral valve repair in neonates and infants can result in a durable freedom from reintervention that parallels freedom from reintervention in older children undergoing repair. Further understanding of mechanisms of failure and better matching of anatomic substrate to strategy is needed.

Structural analysis reveals an amyloid form of the human papillomavirus type 16 E1--E4 protein and provides a molecular basis for its accumulation.

The abundant human papillomavirus (HPV) type 16 E4 protein exists as two distinct structural forms in differentiating epithelial cells. Monomeric full-length 16E1--E4 contains a limited tertiary fold constrained by the N and C termini. N-terminal deletions facilitate the assembly of E1--E4 into amyloid-like fibrils, which bind to thioflavin T. The C-terminal region is highly amyloidogenic, and its deletion abolishes amyloid staining and prevents E1--E4 accumulation. Amyloid-imaging probes can detect 16E1--E4 in biopsy material, as well as 18E1--E4 and 33E1--E4 in monolayer cells, indicating structural conservation. Our results suggest a role for fibril formation in facilitating the accumulation of E1--E4 during HPV infection.

Femoral fracture in pregnancy: a case series and review of clinical management.

Femoral fractures in pregnancy are a rare complication, with an incidence of approximately 1%. Case reports and small trials leave perioperative obstetric management and route of delivery largely unclear. Three cases of femoral fracture are presented that occurred at 24, 30, and 31 weeks of gestation. The causes of femoral fracture were gunshot, motor vehicle collision, and fragility fracture. All fractures were surgically repaired, 1 utilizing neuraxial anesthesia and the others with general anesthesia. A 30-day postoperative course of low-molecular-weight heparin was prescribed, and all patients subsequently had vaginal deliveries. Femoral fractures in the viable pregnancy confer high maternal and fetal morbidity and mortality. Intraoperative fetal monitoring and postoperative anticoagulation should be considered, and vaginal delivery should not be contraindicated.

Evidence of human herpesvirus 6 infection in 4 immunocompetent patients with encephalitis.

We describe 4 patients with encephalitis due to possible reactivation of human herpesvirus 6 (HHV-6) infection who were enrolled in the California Encephalitis Project. All were immunocompetent and had HHV-6 loads determined in cerebrospinal fluid specimens. Tests for detection of HHV-6 should be considered for individuals with encephalitis.

SARS and common viral infections.

In California, molecular testing was useful in decreasing suspicion for severe acute respiratory syndrome (SARS), by detecting common respiratory pathogens (influenza A/B, human metapneumovirus, picornavirus, Mycoplasma pneumoniae, Chlamydia spp., parainfluenza virus, respiratory syncytial virus, and adenovirus) in 23 (45%) of 51 patients with suspected SARS and 9 (47%) of 19 patients with probable SARS.