Heteroplasmic pathogenic m.12315G>A variant in MT-TL2 presenting with MELAS syndrome and depletion of nitric oxide donors.

The MT-TL2 m.12315G>A pathogenic variant has previously been reported in five individuals with mild clinical phenotypes. Herein we report the case of a 5-year-old child with heteroplasmy for this variant who developed neurological regression and stroke-like episodes similar to those observed in mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS). Biochemical evaluation revealed depletion of arginine on plasma amino acid analysis and low z-scores for citrulline on untargeted plasma metabolomics analysis. These findings suggested that decreased availability of nitric oxide may have contributed to the stroke-like episodes. The use of intravenous arginine during stroke-like episodes and daily enteral L-citrulline supplementation normalized her biochemical values of arginine and citrulline. Untargeted plasma metabolomics showed the absence of nicotinamide and 1-methylnicotinamide, and plasma total glutathione levels were low; thus, nicotinamide riboside and N-acetylcysteine therapies were initiated. This report expands the phenotype associated with the rare mitochondrial variant MT-TL2 m.12315G>A to include neurological regression and a MELAS-like phenotype. Individuals with this variant should undergo in-depth biochemical analysis to include untargeted plasma metabolomics, plasma amino acids, and glutathione levels to help guide a targeted approach to treatment.

Risk Stratification and Pain Outcomes Following Revision Total Hip Arthroplasty for Adverse Local Tissue Reactions.

BACKGROUND: Revision total hip arthroplasty (THA) for adverse local tissue reactions (ALTRs) secondary to head-neck taper corrosion is associated with a high complication rate. Diagnosis of ALTR is based on risk stratification using the patient's history and examination, implant risk, serum metal ion levels, and imaging. The purpose of this study was to determine if stratification using similar risk factors is predictive of outcomes following revision THA for metal-on-polyethylene (MoP) ALTR. METHODS: We performed a retrospective review on 141 patients revised for ALTR due to head-neck taper corrosion. Pain outcomes following surgery were analyzed using a generalized linear mixed model. Complications were defined as instability/dislocation, infection, fracture, nerve palsy, leg-length discrepancy, or reoperation. RESULTS: The overall complication rate was 17.7%. The odds of having pain decreased by 44% after revision surgery (Odds Ratio = 0.56, 95% Confidence Interval: 0.324 to 0.952). There was no significant difference in instability/dislocation based on either increased or decreased head-neck offset (P = .67) or magnetic resonance imaging findings of abductor loss, effusion size, and degree of ALTR (P = .73). Increased serum cobalt (P = .31) and chromium (P = .08) levels did not predict complications; however, a decreased cobalt-chromium ratio was associated with postoperative complications (2.8 versus 3.5; P = .002). CONCLUSION: These findings are the first to suggest that patients who have ALTR after MoP THA undergoing revision surgery demonstrated major pain relief. Increasing femoral head offset did not change rates of instability/dislocation. In clinical scenarios where preoperative cobalt-chromium femoral head offsets were greater than available ceramic head offsets, a mandatory decrease in femoral head offset did not increase rates of instability/dislocation.

Evaluating Initial Empiric Therapy for Neutropenic Fever in Vancomycin-Resistant Enterococcus-Colonized Patients.

OBJECTIVES: Vancomycin-resistant enterococcus infections impact mortality in oncology patients. Given the low rate of vancomycin-resistant enterococcus bacteremia, low virulence of vancomycin-resistant enterococcus, and advent of rapid diagnostic systems, vancomycin-resistant enterococcus-directed empiric therapy in vancomycin-resistant enterococcus-colonized patients with neutropenic fever may be unnecessary, promoting increased antimicrobial resistance, drug-related toxicity, and cost. METHODS: Vancomycin-resistant enterococcus-colonized adults admitted for hematopoietic stem cell transplantation or induction therapy for acute leukemia/myeloid sarcoma with neutropenic fever were stratified by vancomycin-resistant enterococcus bacteremia development and empiric vancomycin-resistant enterococcus-directed antimicrobial strategy for first neutropenic fever (Empiric Therapy vs. non-Empiric Therapy). Primary endpoints included vancomycin-resistant enterococcus-related, in-hospital, and 100-day mortality rates. Secondary outcomes included vancomycin-resistant enterococcus bacteremia incidence for first neutropenic fever and the entire hospitalization, length of stay, Clostridioides difficile infection rate, and duration and cost of vancomycin-resistant enterococcus-directed therapy. RESULTS: During first neutropenic fever, 3 of 70 eligible patients (4%) developed vancomycin-resistant enterococcus bacteremia. Although all 3 (100%) were non-Empiric Therapy, no mortality (0%) occurred. Of 67 patients not developing vancomycin-resistant enterococcus bacteremia, 42 (63%) received Empiric Therapy and 25 (37%) non-Empiric Therapy. Empiric Therapy had significantly greater median duration (3 days vs. 0 days; P<.001) and cost ($1604 vs. $0; P<.001) of vancomycin-resistant enterococcus-directed therapy but demonstrated no significant differences in clinical outcomes. CONCLUSION: Available data suggest Empiric Therapy may offer no clinical benefit to this population, regardless of whether vancomycin-resistant enterococcus is identified in blood culture or no pathogen is found. Such an approach may only expose the majority of patients to unnecessary vancomycin-resistant enterococcus-directed therapy and drug-related toxicities while increasing institutional drug and monitoring costs. Even in the few patients developing vancomycin-resistant enterococcus bacteremia, waiting until the organism is identified in culture to start directed therapy likely makes no difference in mortality. This lack of benefit warrants consideration to potentially omit empiric vancomycin-resistant enterococcus-directed therapy in first neutropenic fever in many of these patients.

Integrative Medicine: Manual Therapy.

Manual therapy, or manipulative therapy, is performed primarily by osteopathic physicians, chiropractors, and physical therapists to relieve pain and improve function. As safe prescribing of opioids has become a concern and nondrug therapies for pain management are used more widely, manual therapy has become an attractive treatment option for many patients. A variety of techniques are used, including myofascial release, strain-counterstrain, muscle energy, high velocity/low amplitude, Still, and others. The most common conditions for which patients seek manual therapies are back pain, neck pain, and extremity problems. These therapies also are used to manage many other conditions. Studies show that, in general, manual therapies may improve pain and function in the short and moderate term in patients with acute and chronic back pain, neck pain, rotator cuff conditions, and temporomandibular joint disorders. These therapies also are used in patients with sciatica, migraine, carpal tunnel syndrome, pregnancy-related pelvic girdle pain, and infantile colic. Manual therapies may result in improvements in these conditions, but there is no high-quality research to confirm their benefits. Many studies show benefits that are similar to those of other commonly used therapies, or that are not superior to the benefits shown with sham manipulation.

Integrative Medicine: Cannabis and Cannabis-Related Drugs.

Cannabis is a genus of flowering herbs in the Cannabaceae family. Federal law defines dried plant material preparations of the subspecies Cannabis sativa as marijuana. The term cannabis refers to all products derived from Cannabis plants. The active compounds in cannabis are cannabinoids, which include delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC is the psychoactive component, whereas CBD has no psychoactive effects. There are three Food and Drug Administration (FDA)-approved cannabis-related drugs. Dronabinol and nabilone (Cesamet) are approved for chemotherapy-induced nausea and vomiting; cannabidiol (Epidiolex) is approved for two pediatric epilepsy syndromes. FDA-approved cannabis-related drugs, marijuana, and cannabis formulations have been studied for the management of other conditions and symptoms (eg, cachexia, chemotherapy-induced nausea and vomiting, chronic pain, muscle spasticity) and have shown varying effectiveness. CBD formulations have been shown to be effective for certain forms of epilepsy. However, marijuana, cannabis-containing products, and cannabis-derived products in general are not approved by the FDA for any indication. Adverse effects include impaired executive function, cognition, and driving. Physicians can recommend use of marijuana under medical marijuana laws but cannot prescribe it, as it is classified as a Schedule I controlled substance. Laws regulating use of marijuana and cannabis products vary among states.

Postdischarge thromboembolic outcomes and mortality of hospitalized patients with COVID-19: the CORE-19 registry.

Thromboembolic events, including venous thromboembolism (VTE) and arterial thromboembolism (ATE), and mortality from subclinical thrombotic events occur frequently in coronavirus disease 2019 (COVID-19) inpatients. Whether the risk extends postdischarge has been controversial. Our prospective registry included consecutive patients with COVID-19 hospitalized within our multihospital system from 1 March to 31 May 2020. We captured demographics, comorbidities, laboratory parameters, medications, postdischarge thromboprophylaxis, and 90-day outcomes. Data from electronic health records, health informatics exchange, radiology database, and telephonic follow-up were merged. Primary outcome was a composite of adjudicated VTE, ATE, and all-cause mortality (ACM). Principal safety outcome was major bleeding (MB). Among 4906 patients (53.7% male), mean age was 61.7 years. Comorbidities included hypertension (38.6%), diabetes (25.1%), obesity (18.9%), and cancer history (13.1%). Postdischarge thromboprophylaxis was prescribed in 13.2%. VTE rate was 1.55%; ATE, 1.71%; ΑCM, 4.83%; and MB, 1.73%. Composite primary outcome rate was 7.13% and significantly associated with advanced age (odds ratio [OR], 3.66; 95% CI, 2.84-4.71), prior VTE (OR, 2.99; 95% CI, 2.00-4.47), intensive care unit (ICU) stay (OR, 2.22; 95% CI, 1.78-2.93), chronic kidney disease (CKD; OR, 2.10; 95% CI, 1.47-3.0), peripheral arterial disease (OR, 2.04; 95% CI, 1.10-3.80), carotid occlusive disease (OR, 2.02; 95% CI, 1.30-3.14), IMPROVE-DD VTE score ≥4 (OR, 1.51; 95% CI, 1.06-2.14), and coronary artery disease (OR, 1.50; 95% CI, 1.04-2.17). Postdischarge anticoagulation was significantly associated with reduction in primary outcome (OR, 0.54; 95% CI, 0.47-0.81). Postdischarge VTE, ATE, and ACM occurred frequently after COVID-19 hospitalization. Advanced age, cardiovascular risk factors, CKD, IMPROVE-DD VTE score ≥4, and ICU stay increased risk. Postdischarge anticoagulation reduced risk by 46%.

Dural Convexity Chondroma Mimicking Meningioma in a Young Female.

Intracranial meningeal convexity chondroma is a rare benign lesion hypothesized to stem from remnant chondrocyte precursors of embryonic origin. This lesion often masquerades as meningioma given the similar dural-based attachment and pattern of calcification. We describe the case of a 26-year-old female with incidentally discovered convexity meningeal chondroma, originally presumed to be a meningioma. In this case, we share our diagnostic and operative intervention and outcome and discuss the unique pathologic findings in this lesion that differentiate it from similar appearing lesions. To the authors' knowledge, there are fewer than 20 cases of convexity meningeal chondroma in the literature; thus, we also provide a brief review of the literature regarding this rare pathology.

Comparison of Asymptomatic and Symptomatic Adverse Local Tissue Reaction in Patients With Head-Neck Taper Corrosion.

BACKGROUND: Diagnosis of adverse local tissue reaction (ALTR) in metal-on-polyethylene (MoP) total hip arthroplasty (THA) secondary to head-neck taper corrosion is challenging. The purpose of this study is to compare differences between asymptomatic and symptomatic ALTR in an observational cohort, including presentation, metal ion differences, and metal artifact reduction sequence (MARS) magnetic resonance imaging (MRI) findings. METHODS: We performed a retrospective review of an observational cohort of 492 MoP THA patients at increased risk of developing ALTR. Ninety-four patients underwent revision arthroplasty for ALTR. Patients were stratified into symptomatic and asymptomatic ALTR groups. Presentation, metal ion levels, and imaging findings were compared. RESULTS: For patients with confirmed ALTR, 41% were asymptomatic. There was a statistically significant difference in the serum chromium levels between symptomatic and asymptomatic ALTR patients (2.2 µg/L vs 3.1 µg/L, P = .05). There was no statistically significant difference between the serum cobalt levels or MRI findings in these 2 groups. We observed that extracapsular disease associated with ALTR could be misinterpreted as trochanteric bursitis. CONCLUSION: Almost half of the MoP THA ALTR cases identified were asymptomatic. Cobalt levels could not differentiate between symptomatic and asymptomatic pseudotumor formation. Symptomatic and asymptomatic MoP ALTRs have similar MARS MRI characteristics. Our findings suggest that it is essential to risk stratify patients who could potentially have ALTR based on implant type, symptoms, ion levels, and MARS MRI.

New insights into structural features and optimal detection of circulating tumor DNA determined by single-strand DNA analysis.

Circulating cell-free DNA (cfDNA) has received increasing interest as an apparent breakthrough approach in diagnostics, personalized medicine, and tumor biology. However, the structural features of cfDNA are poorly characterized. Specifically, the literature has discrepancies with regards to cfDNA size profile. We performed a blinded study of the distribution of cfDNA fragment sizes in cancer patient plasma (n = 11), by various ultra-deep-sequencing approaches and quantitative PCR (Q-PCR). Whole-genome sequencing of single-stranded DNA library preparation (SSP-S) revealed that nearly half of the total cfDNA fragment number are below 120 nucleotides, which are not readily detectable by standard double-stranded DNA library preparation (DSP) protocols. Fractional size distribution of cancer patient circulating DNA was very similar using both SSP-S-based or Q-PCR-based methods also revealing that high molecular weight (over 350 bp) cfDNA is a minor component (~2%). These extra small detected cfDNA fragments may mostly result from nicks occurring in blood circulation in one or both DNA strands, which are subsequently revealed through the denaturation step of the SSP and Q-PCR procedures. Detailed analysis of the data suggested that most of the detectable cfDNA in blood has a nucleosome footprint (∼10-bp periodicity repeats). The nucleosome is thus the most stabilizing structure of DNA in the circulation. cfDNA molecules, which are initially packed in chromatin, are released from cells and are then dynamically degraded in blood both within and between nucleosomes or transcription factor-associated subcomplexes. While this study provides new insights into cfDNA size profiles harmonizing sequencing and Q-PCR findings, our data validate the use of a specific Q-PCR method and SSP-S for obtaining an optimal qualitative and quantitative analytical signal.

Impact of Primary Tumor Location on First-line Bevacizumab or Cetuximab in Metastatic Colorectal Cancer.

BACKGROUND: Colorectal cancer is one of the most common malignancies in the United States, with a large proportion of patients presenting with metastatic disease or developing a recurrence. Systemic chemotherapy is the mainstay of therapy in this setting. There is a clear benefit in the addition of bevacizumab or cetuximab (for rat sarcoma [RAS] wild type tumors) to oxaliplatin- and irinotecan-based regimens which can be considered for first-line therapy. However, many significant questions remain as to which agent reflects best practice. OBJECTIVE: Our review aimed to elucidate the benefit of adding bevacizumab and cetuximab to initial therapy for metastatic colorectal cancer based on primary tumor location and a variety of other disease- and patient-related factors, addressing the paucity of evidence that currently exists in this area and contributing to current literature and clinical practices. METHODS: The primary endpoints of the study were first Progression-Free Survival (PFS) and Overall Survival (OS). Secondary endpoints included best response to first- and second-line therapies, Treatment- Related Adverse Events (TRAEs), second PFS, cost of therapy, and an assessment of other patient- and disease-related factors affecting PFS and OS. RESULTS: While there were trends towards improved OS in patients with left-sided primary tumors (n=57) compared to those with right-sided disease (n=23), there were no significant differences between the two groups in either primary endpoint. While no differences were found for patients with left- or right- sided tumors stratified by add-on agent, these analyses were limited by the small number of patients receiving cetuximab with first-line therapy (n=4). However, the bevacizumab cohort (n=76) was sizable enough to provide ample data and produce clinically relevant results. Add-on therapy with bevacizumab in our study achieved impressive survival outcomes in both left-sided (median first PFS = 13 months, 95% CI 11-15 months; median OS = 37 months, 95% CI 21-53 months) and right-sided (median first PFS = 13 months, 95% CI 9-17 months; median OS = 37 months, 95% CI 22-52 months) disease. CONCLUSION: These results raised questions regarding the true significance of primary tumor location when selecting bevacizumab or cetuximab for first-line therapy, particularly the current thought of using cetuximab for left-sided tumors. While the superiority of bevacizumab over cetuximab in rightsided disease remained evident upon comparison of our analysis with historical controls, survival outcomes with the agent in our analysis appeared to be similar to that of cetuximab in CRYSTAL, FIRE- 3, and CALGB/SWOG 80405 in left-sided disease. Further study is required to determine if bevacizumab truly does produce similar outcomes to cetuximab in left-sided primary tumors.

Early Antimicrobial De-escalation and Stewardship in Adult Hematopoietic Stem Cell Transplantation Recipients: Retrospective Review.

BACKGROUND: Antimicrobial stewardship in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients remains underutilized in North America. European guidelines advise de-escalation of broad-spectrum therapy after 72 hours in select patients with neutropenic fever of unknown origin. This is not commonplace in the United States, as current guidelines recommend broad-spectrum therapy until neutrophil engraftment. If de-escalating after at least 5 days of broad-spectrum therapy and defervescence in neutropenic allo-HSCT recipients does not predispose them to recurrent fever or infection, the practice could afford several benefits. METHODS: The primary end point was rate of recurrent fever. Secondary outcomes included Clostridium difficile-associated infections, length of stay, intensive care unit (ICU) admission incidence, in-hospital mortality rate, need for re-escalation of therapy, rate of positive blood cultures for patients who had recurrent fevers, overall antimicrobial utilization from neutropenic fever onset, and pharmacoeconomic impact. RESULTS: A total of 120 patients were assessed in 2 groups as cohort 1 (n = 46), which received early de-escalation, and cohort 2 (n = 74), which did not. The primary end point met criteria for noninferiority, as 7 patients (15%) in cohort 1 had recurrent fever within the specified time frame compared with 14 (19%) in cohort 2 (90% CI, -0.0878 to 0.1629, P = .026). Patients in cohort 1 received significantly less gram-positive broad-spectrum antimicrobials, with trends toward lower use of broad-spectrum gram-negative agents and lower associated costs and no differences in length of stay, ICU admission incidence, need for re-escalation of therapy, rate of culture-positive bacteremia after de-escalation or discontinuation of broad-spectrum therapy, or in-hospital mortality rate. CONCLUSIONS: De-escalating after at least 5 days of broad-spectrum therapy and defervescence did not appear to affect the rate of recurrent fever. This allowed for significant reductions in gram-positive broad-spectrum antimicrobial utilization, with trends toward lower use of broad-spectrum gram-negative agents and associated costs and no difference in clinical outcomes compared with those continuing such therapy until neutrophil engraftment.

Serotonin Syndrome Complicating Treatment of Ifosfamide Neurotoxicity With Methylene Blue.

Methylene blue is a widely used treatment for ifosfamide neurotoxicity. We present a case of severe encephalopathy complicating ifosfamide-based therapy for recurrent retroperitoneal leiomyosarcoma. After treatment with methylene blue, the patient experienced clinical decompensation and was diagnosed with serotonin syndrome based on a constellation of clinical findings. Withdrawal of methylene blue and other serotonergic medications led to clinical stabilization and ultimately neurological recovery. Our case highlights the challenge of diagnosing serotonin syndrome in the face of preexisting ifosfamide neurotoxicity, as there is significant clinical overlap between these 2 syndromes. Practitioners must remain vigilant of this potential life-threatening complication in this vulnerable population.

Successful management of Mycobacterium haemophilum lower extremity cutaneous infection in a matched-unrelated donor stem cell transplant recipient.

Nontuberculous mycobacterial infections can often occur in individuals with adequate immune function. Such infections typically have cutaneous involvement and are caused by rapidly growing mycobacterium. Other nontuberculous mycobacteria species, like Mycobacterium haemophilum, almost always present as opportunistic infections occurring in severely immunocompromised hosts. Here, we present a complicated and protracted course of diagnosing M. haemophilum lower extremity cutaneous infection in a matched-unrelated donor stem cell transplant recipient.

Pharmacy Report: Megestrol Acetate-Induced Adrenal Insufficiency.

A man aged 65 years with metastatic renal cell carcinoma presented for evaluation after a recent fall. A thorough workup of the case was performed and secondary adrenal insufficiency induced by the administration of megestrol acetate was determined to be the cause. Adrenal insufficiency is a serious disorder that is a potential adverse event of megestrol acetate, a medication used to help patients with cancer cachexia increase their appetite and gain weight. This association is not well recognized in clinical practice, so this case highlights the importance of distinguishing possible endocrine complications induced by the long-term administration or sudden discontinuation of megestrol acetate.

Impact of intravenous magnesium infusion rate during ambulatory replacements on serum magnesium concentrations after allogeneic stem cell transplant.

PURPOSE: For an outpatient cancer center to operate efficiently, optimizing the use of chair time is essential. Allogeneic hematopoietic cell transplant (allo-HCT) recipients are seen frequently in this setting after hospital discharge and regularly for several months thereafter. Aggressive electrolyte replacement is commonly required in these patients, primarily due to renal wasting with calcineurin inhibitor use. Frequent intravenous (IV) magnesium repletion, requiring several hours of infusion time, is often needed in these patients to adequately manage their magnesium deficiencies. The purpose of this study is to explore the impact of extending the infusion rate of intravenous magnesium sulfate on the frequency and degree of IV magnesium replacements required in allo-HCT recipients. METHODS: We conducted a retrospective study to compare two cohorts of patients administered IV magnesium sulfate at a rate of 4 g/1 h versus 4 g/2 h. RESULTS: A total of 103 continuous patients were assessed in two groups as cohort 1 at the 4 g/1 h rate and cohort 2 at the 4 g/2 h rate. Cohort 1 required less IV magnesium per outpatient visit (median 2.2 vs. 2.9 g/visit, P = 0.0211) and less total IV magnesium replacement through day +100 (median 68 vs. 85 g, P = 0.0479) than cohort 2. CONCLUSION: These data suggest that there is no apparent benefit of prolonging magnesium infusion from 1 to 2 h in our outpatient allo-HCT population.

Cell-free DNA Comprises an In Vivo Nucleosome Footprint that Informs Its Tissues-Of-Origin.

Nucleosome positioning varies between cell types. By deep sequencing cell-free DNA (cfDNA), isolated from circulating blood plasma, we generated maps of genome-wide in vivo nucleosome occupancy and found that short cfDNA fragments harbor footprints of transcription factors. The cfDNA nucleosome occupancies correlate well with the nuclear architecture, gene structure, and expression observed in cells, suggesting that they could inform the cell type of origin. Nucleosome spacing inferred from cfDNA in healthy individuals correlates most strongly with epigenetic features of lymphoid and myeloid cells, consistent with hematopoietic cell death as the normal source of cfDNA. We build on this observation to show how nucleosome footprints can be used to infer cell types contributing to cfDNA in pathological states such as cancer. Since this strategy does not rely on genetic differences to distinguish between contributing tissues, it may enable the noninvasive monitoring of a much broader set of clinical conditions than currently possible.

Predicted structure and domain organization of rotavirus capping enzyme and innate immune antagonist VP3.

UNLABELLED: Rotaviruses and orbiviruses are nonturreted Reoviridae members. The rotavirus VP3 protein is a multifunctional capping enzyme and antagonist of the interferon-induced cellular oligoadenylate synthetase-RNase L pathway. Despite mediating important processes, VP3 is the sole protein component of the rotavirus virion whose structure remains unknown. In the current study, we used sequence alignment and homology modeling to identify features common to nonturreted Reoviridae capping enzymes and to predict the domain organization, structure, and active sites of rotavirus VP3. Our results suggest that orbivirus and rotavirus capping enzymes share a domain arrangement similar to that of the bluetongue virus capping enzyme. Sequence alignments revealed conserved motifs and suggested that rotavirus and orbivirus capping enzymes contain a variable N-terminal domain, a central guanine-N7-methyltransferase domain that contains an additional inserted domain, and a C-terminal guanylyltransferase and RNA 5'-triphosphatase domain. Sequence conservation and homology modeling suggested that the insertion in the guanine-N7-methyltransferase domain is a ribose-2'-O-methyltransferase domain for most rotavirus species. Our analyses permitted putative identification of rotavirus VP3 active-site residues, including those that form the ribose-2'-O-methyltransferase catalytic tetrad, interact with S-adenosyl-l-methionine, and contribute to autoguanylation. Previous reports have indicated that group A rotavirus VP3 contains a C-terminal 2H-phosphodiesterase domain that can cleave 2'-5' oligoadenylates, thereby preventing RNase L activation. Our results suggest that a C-terminal phosphodiesterase domain is present in the capping enzymes from two additional rotavirus species. Together, these findings provide insight into a poorly understood area of rotavirus biology and are a springboard for future biochemical and structural studies of VP3. IMPORTANCE: Rotaviruses are an important cause of severe diarrheal disease. The rotavirus VP3 protein caps viral mRNAs and helps combat cellular innate antiviral defenses, but little is known about its structure or enzymatic mechanisms. In this study, we used sequence- and structure-based alignments with related proteins to predict the structure of VP3 and identify enzymatic domains and active sites therein. This work provides insight into the mechanisms of rotavirus transcription and evasion of host innate immune defenses. An improved understanding of these processes may aid our ability to develop rotavirus vaccines and therapeutics.

PT-ACRAMTU, a platinum-acridine anticancer agent, lengthens and aggregates, but does not stiffen or soften DNA.

We used atomic force microscopy (AFM) to study the dose-dependent change in conformational and mechanical properties of DNA treated with PT-ACRAMTU ([PtCl(en)(ACRAMTU-S)](NO3)2, (en = ethane-1,2-diamine, ACRAMTU = 1-[2-(acridin-9-ylamino)ethyl]-1,3-dimethylthiourea. PT-ACRAMTU is the parent drug of a family of non-classical platinum-based agents that show potent activity in non-small cell lung cancer in vitro and in vivo. Its acridine moiety intercalates between DNA bases, while the platinum group forms mono-adducts with DNA bases. AFM images show that PT-ACRAMTU causes some DNA looping and aggregation at drug-to-base pair ratio (r b) of 0.1 and higher. Very significant lengthening of the DNA was observed with increasing doses of PT-ACRAMTU, and reached saturation at an r b of 0.15. At r b of 0.1, lengthening was 0.6 nm per drug molecule, which is more than one fully stretched base pair stack can accommodate, indicating that ACRAMTU also disturbs the stacking of neighboring base pair stacks. Analysis of the AFM images based on the worm-like chain (WLC) model showed that PT-ACRAMTU did not change the flexibility of (non-aggregated) DNA, despite the extreme lengthening. The persistence length of untreated DNA and DNA treated with PT-ACRAMTU was in the range of 49-65 nm. Potential consequences of the perturbations caused by this agent for the recognition and processing of the DNA adducts it forms are discussed.

Malignant struma ovarii: a blinded study of 86 cases assessing which histologic features correlate with aggressive clinical behavior.

CONTEXT: Struma ovarii exhibiting malignant histology are uncommon, and an aggressive clinical course in the form of initial extraovarian spread or recurrence is even more exceptional for these tumors. OBJECTIVE: To determine whether specific histologic features have predictive value in distinguishing clinically benign from clinically malignant struma ovarii. DESIGN: Blinded analysis of 19 histologic characteristics of thyroid tumors was performed in 60 clinically benign and 26 clinically malignant struma ovarii cases, with long-term follow-up. RESULTS: Except for lack of fibrosis and macrofollicular pattern, which were more common in biologically malignant tumors (P  =  .04 and P  =  .008, respectively), and trabecular pattern, which was associated with a benign clinical course (P  =  .03), none of the other histologic features was found to be correlated with clinical behavior. The presence of the following features was similar in the biologically benign and malignant tumors: papillae, pseudo-papillae, psammoma bodies, nuclear grooves, nuclear overlap, "orphan Annie" nuclei, nuclear pseudo-inclusions, prominent nucleoli, hypercellularity, colloid scalloping, eosinophilic cytoplasm, mitoses, vascular invasion, cytologic atypia, nuclear pleomorphism, and cell size and type. Trabecular pattern and absence of fibrosis were uncommon, and there was considerable overlap of macrofollicular pattern ratio between benign and malignant cases. Thus, their practical usefulness is uncertain. CONCLUSIONS: The clinical outcome of struma ovarii cannot be predicted based on the microscopic diagnosis of the thyroid tissue or on specific histologic features. The lack of correlation between morphology and outcome in proliferative and histologically malignant struma ovarii is striking, making the behavior of these tumors particularly unpredictable.

Malignant struma ovarii: an analysis of 88 cases, including 27 with extraovarian spread.

Struma ovarii that display extraovarian spread or later recurrence is exceedingly rare. Among 88 patients with "malignant" struma ovarii followed for prolonged periods, several features helped to predict the adverse clinical course. Adhesions (graded 2 to 4+), peritoneal fluid (> or =1 L) or ovarian serosal rent were worrisome features, occurring in 74% of 27 biologically malignant tumors but only 10% of 61 clinically benign tumors. The size of the strumal component rather than the overall size of the ovarian teratoma also had some predictive value. Tumors with a strumal component < or =6 cm recurred rarely (7%), whereas 33% of the consult and 88% of the literature cases > or =12 cm were clinically malignant. Except for a papillary pattern or poorly differentiated cancer, no microscopic feature reliably predicted the clinical outcome, including those typically associated with malignancy in primary thyroid tumors. Among the consult cases, 7% with histologic follicular adenomas and 29% with papillary carcinomas were clinically malignant. Unequivocal vascular invasion was rare, precluding assessment of its effect. Optically clear nuclei, when extensive, were useful to diagnose papillary carcinoma, but were present nevertheless in smaller numbers in both macrofollicular and microfollicular adenomas. Eight tumors confined initially to the ovary (stage 1) recurred. Papillary carcinomas recurred earlier (average 4 y) than follicular adenomatous neoplasms (average 11 y, range: 1-29 y). Overall, the survival rate for all patients was 89% at 10 years and 84% at 25 years, indicating the need for routine long-term follow-up.