Assessment of the safety of nivolumab in people living with HIV with advanced cancer on antiretroviral therapy: the AIDS Malignancy Consortium 095 Study.

BACKGROUND: Although immunotherapy has emerged as a therapeutic strategy for many cancers, there are limited studies establishing the safety and efficacy in people living with HIV (PLWH) and cancer. METHODS: PLWH and solid tumors or Kaposi sarcoma (KS) receiving antiretroviral therapy and a suppressed HIV viral load received nivolumab at 3 mg/kg every 2 weeks, in two dose deescalation cohorts stratified by CD4 count (stratum 1: CD4 count > 200/µL and stratum 2: CD4 count 100-199/µL). An expansion cohort of 24 participants with a CD4 count > 200/µL was then enrolled. RESULTS: A total of 36 PLWH received nivolumab, including 15 with KS and 21 with a variety of other solid tumors. None of the first 12 participants had dose-limiting toxicity in both CD4 strata, and five patients (14%) overall had grade 3 or higher immune related adverse events. Objective partial response occurred in nine PLWH and cancer (25%), including in six of 15 with KS (40%; 95% CI, 16.3-64.7). The median duration of response was 9.0 months overall and 12.5 months in KS. Responses were observed regardless of PDL1 expression. There were no significant changes in CD4 count or HIV viral load. CONCLUSIONS: Nivolumab has a safety profile in PLWH similar to HIV-negative subjects with cancer, and also efficacy in KS. Plasma HIV remained suppressed and CD4 counts remained stable during treatment and antiretroviral therapy, indicating no adverse impact on immune function. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02408861.

Serum free light chains among twin siblings: is the kappa/lambda ratio genetically determined?

BACKGROUND: Serum kappa, lambda, the K/λ light chain concentrations are used for screening, diagnosis, and monitoring of patients with multiple myeloma and other plasma cell disorders. Biological variation studies conducted on healthy subjects showed that free light chains have a low within and high between-individual variation. We determined if this variation were genetically linked. METHODS: We obtained a single serum sample from 16 pairs of identical twins, 8 neonate twins, and 19 presumed directly-related siblings children, measured Κ and λ light chains and computed the Κ/λ ratio. RESULTS: As expected, Κ/λ results from each twin neonate were near identical (reflecting maternal/placental transfer). For older children and adult twins, the Κ/λ ratio form a cluster of results that were a subset of the reference range. There was one outlier, a female with a high, different from her twin sister. She likely had a monoclonal gammopathy (no followup was possible). Excluding this pair, results from neonate twins (14.4% ±10.3%) and non-neonate twins (18.0 ± 15.3%) were not significantly different. Results between non-twin siblings were more scattered (53.2%±53.4%) and different from neonate and non-neonate twin adult and children. CONCLUSION: We suggest that the Κ/λ free light chains may be genetically linked.

Frequency of high-grade squamous cervical lesions among women over age 65 years living with HIV.

BACKGROUND: Current US cervical cancer screening guidelines recommend screening cessation at the age of 65 years provided women have adequate previous screening and no history of precancer. Women living with HIV are at higher risk of cervical cancer than women living without HIV. Furthermore, limited data exists to quantify the risk of cervical cancer among women who otherwise would qualify for screening cessation. OBJECTIVE: This study aimed to determine whether guidelines recommending women to discontinue cervical cancer screening at the age of 65 years are appropriate for women living with HIV. STUDY DESIGN: Semiannual Papanicolaou testing was performed as part of surveillance visits in the Women's Interagency HIV Study. Launched in October 1994, the Women's Interagency HIV Study is a federally funded US multisite cohort study that has enrolled 3678 women living with HIV and 1304 women living without HIV; we included data throughout September 2019 onward. Conventional Papanicolaou tests were collected at scheduled 6-month visits and read centrally according to the 1991 Bethesda System criteria. Results were analyzed among women at least 65 years of age. The primary endpoint was high-grade cytology, including high-grade squamous intraepithelial lesions; atypical glandular cells; atypical squamous cells, cannot exclude high-grade lesions; and malignant cytology. Wilcoxon rank-sum tests were used to compare the continuous variables, and Chi-square tests or the Fisher exact tests were used to compare the categorical variables. The Kaplan-Meier method was used to calculate the cumulative incidence. Poisson regression was used to compare 2 incidence rates. RESULTS: Of 169 eligible women (121 women living with HIV and 48 women living without HIV) who contributed 678.4 person-years of observation after reaching the age of 65 years, 2.2% had high-grade cytologic abnormalities. However, no cancer was found. Furthermore, 20 women had previous precancer results, and 74 women had abnormal Papanicolaou test results in the previous decade. Among 50 women (38 women living with HIV and 12 women living without HIV) with a previous hysterectomy and no history of cervical precancer, the cumulative incidence rates of high-grade squamous intraepithelial lesions were 0.6 (95% confidence interval, 0.0-3.2) per 100 person-years for women living with HIV and 0.0 (95% confidence interval, 0.0-8.1) per 100 person-years for women living without HIV (P=.61). Only 48 women (27 women living with HIV and 21 women living without HIV) had cervices and met the current guidelines to discontinue screening; their risk of experiencing high-grade squamous intraepithelial lesions was 2.2 (95% confidence interval, 0.6-5.5) per 100 person-years overall and did not vary by HIV status (2.3 [95% confidence interval, 0.5-6.8] per 100 person-years for women living with HIV and 1.8 [95% confidence interval, 0.0-9.8] per 100 person-years for women living without HIV; P=.81). CONCLUSION: Most women living with HIV do not meet the criteria for cervical cancer screening cessation and will need to continue screening over the age of 65 years; however, women who meet the criteria for screening cessation have risks of high-grade squamous lesions similar to women living without HIV and may choose to discontinue.

Increased prevalence of inattention-related symptoms in a large cohort of patients with congenital heart disease.

The objective of this study is to assess the prevalence and risk factors for attention-deficit hyperactivity disorder (ADHD) in a large cohort of patients with congenital heart disease (CHD). Patients (n = 695) with CHD who were aged 6-15 years and visited the outpatient clinics in our hospital from June 2015 to May 2017 were enrolled. Their medical records were collected, and the Chinese version of the Swanson, Nolan, and Pelham rating scale (SNAP-IVc) and a questionnaire about neuropsychiatric care-seeking behavior were completed by parents and counselors. Of the 695 patients, the overall prevalence of ADHD was 12.4%, including 3.2% for the combined subtype, 6.8% for the inattentive-predominant subtype, and 2.4% for the hyperactivity/impulsive-predominant subtype. Only the inattention-predominant subtype was significantly more prevalent than in the general population. The prevalence of the inattention-predominant subtype was highest in the patients with cyanotic CHD, high severity index, and in those who had received surgery or cardiopulmonary bypass. Multivariate regression analysis indicated that the risk factors for inattention-related symptoms included postoperative seizure and previous cardiopulmonary bypass (odds ratio: 3.22 and 3.82; P = 0.027 and < 0.001, respectively). Only 58.7% of the patients with probable ADHD ever sought neuropsychiatric care, and only 27% regularly attended neuropsychiatric clinics. The inattention-predominant subtype of ADHD was more prevalent in our CHD patients, especially in those with cyanotic CHD, higher disease severity index, and in those who had undergone a surgical intervention. The percentage of patients receiving regular neuropsychiatric clinic follow-up was low.

Age Differences in the Mediating Effects of Parenting Stress on the Relationship Between Cyanotic Congenital Heart Disease and Externalizing Problems in Children and Adolescents.

BACKGROUND: Cyanotic congenital heart disease (CHD) has detrimental effects on behavioral function in children and adolescents. However, few study authors have examined the underlying mechanisms of these effects. OBJECTIVE: The aims of this study were to investigate the mediating effects of parenting stress in the association between cyanotic CHD and externalizing problems and to explore whether age moderated these mediating effects. METHODS: A total of 697 children and adolescents (aged 2-17 years) with CHD (252 with cyanotic CHD and 445 with acyanotic CHD) in Taiwan were enrolled. The Child Behavior Checklist and the Parenting Stress Index were used to assess externalizing problems and parenting stress, respectively. Mediation analysis was performed to determine the mediating effects of parenting stress in the association between cyanotic CHD and externalizing problems. A moderated mediation model was used to investigate the moderating effect of age on the observed mediating effects. RESULTS: Parenting stress significantly mediated the relationship between cyanotic CHD and externalizing problems (unstandardized coefficient B = 0.98; 95% bootstrap confidence interval, 0.23-1.78). Children's age further moderated the mediating effects, with greater effects in older children. Age also moderated the association between cyanotic CHD and parenting stress, such that the effects were only significant in children older than 5.7 years. CONCLUSIONS: Our study revealed that age affected the mediating effects of parenting stress in the relationship between cyanotic CHD and externalizing problems. Efforts to reduce externalizing problems in children and adolescents with cyanotic CHD by targeting parenting stress may be more effective when age differences are considered.

Factors Impacting Differential Outcomes in the Definitive Radiation Treatment of Anal Cancer Between HIV-Positive and HIV-Negative Patients.

BACKGROUND: Anal squamous cell carcinoma (ASCC) is uncommon, yet seen more frequently in the setting of the human immunodeficiency virus (HIV). Chemoradiotherapy is the definitive modality of treatment for patients with ASCC; this study examines factors impacting clinical outcomes in a large cohort of HIV-positive and HIV-negative patients. METHODS: A retrospective review was conducted of patients treated for nonmetastatic ASCC at a single institution between 2005 and 2018. Freedom from local recurrence (FFLR), freedom from distant metastasis, and overall survival (OS) were calculated using the Kaplan-Meier method, and univariate and multivariate analysis were performed using the Cox proportional hazards model. RESULTS: During the study period, 111 patients initiated definitive treatment for ASCC. Median age of the entire cohort was 56.7 years (interquartile range, 51.5-63.5), with 52 patients (46.8%) being HIV-positive. At median follow-up of 28.0 months, the 2- and 5-year FFLR were 78.2% (95% confidence interval [CI], 70.4-87.0) and 74.6% (95% CI, 65.8-84.5), respectively. Multivariate analysis revealed time from diagnosis to treatment initiation (median, 8 weeks; hazard ratio, 1.06; 95% CI, 1.03-1.10) to be significantly associated with worse FFLR and OS. HIV-positive patients had a trend toward worse FFLR (log-ranked p = .06). For HIV-positive patients with post-treatment CD4 less than 150 cells per mm3 , there was significantly worse OS (log-ranked p = .015). CONCLUSION: A trend toward worse FFLR was seen in HIV-positive patients, despite similar baseline disease characteristics as HIV-negative patients. Worse FFLR and OS was significantly associated with increased time from diagnosis to treatment initiation. Poorer OS was seen in HIV-positive patients with a post-treatment CD4 count less than 150 cells per mm3 . IMPLICATIONS FOR PRACTICE: Human immunodeficiency virus (HIV)-positive patients with anal squamous cell carcinoma can represent a difficult clinical scenario. Definitive radiation with concurrent chemotherapy is highly effective but can result in significant toxicity and a decrease in CD4 count that could predispose to HIV-related complications. As HIV-positive patients have largely been excluded from prospective clinical trials, this study seeks to provide greater understanding of their outcomes with radiation therapy, potential predictors of worse local control and overall survival, and those most at risk after completion of treatment.

AIDS-Related Kaposi Sarcoma, Version 2.2019, NCCN Clinical Practice Guidelines in Oncology.

As treatment of HIV has improved, people living with HIV (PLWH) have experienced a decreased risk of AIDS and AIDS-defining cancers (non-Hodgkin's lymphoma, Kaposi sarcoma, and cervical cancer), but the risk of Kaposi sarcoma in PLWH is still elevated about 500-fold compared with the general population in the United States. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for AIDS-Related Kaposi Sarcoma provide diagnosis, treatment, and surveillance recommendations for PLWH who develop limited cutaneous Kaposi sarcoma and for those with advanced cutaneous, oral, visceral, or nodal disease.

HPV-Associated Anal Cancer in the HIV/AIDS Patient.

The prevalence of anal human papillomavirus (HPV) infection and anal high-grade squamous intraepithelial lesion (HSIL) remain high among HIV-infected individuals on effective antiretroviral therapy (ART). The incidence of HPV-related anal cancers has continued to increase since the introduction of ART. Therefore, ART may confer only limited benefit with respect to reducing the risk of anal HSIL and cancer. Efforts are in progress to define the efficacy of secondary prevention programs for prevention of anal cancer. In the modern ART era, anal cancer recurrence and survival outcomes are similar in HIV-infected and HIV-uninfected patients, but HIV-infected patients may experience more toxicities. This article reviews the current literature on HPV-associated anal cancer in the HIV-infected population, including epidemiology, screening, clinical characteristics, and treatment outcomes.

Cancer in People Living With HIV, Version 1.2018, NCCN Clinical Practice Guidelines in Oncology.

People living with HIV (PLWH) are diagnosed with cancer at an increased rate over the general population and generally have a higher mortality due to delayed diagnoses, advanced cancer stage, comorbidities, immunosuppression, and cancer treatment disparities. Lack of guidelines and provider education has led to substandard cancer care being offered to PLWH. To fill that gap, the NCCN Guidelines for Cancer in PLWH were developed; they provide treatment recommendations for PLWH who develop non-small cell lung cancer, anal cancer, Hodgkin lymphoma, and cervical cancer. In addition, the NCCN Guidelines outline advice regarding HIV management during cancer therapy; drug-drug interactions between antiretroviral treatments and cancer therapies; and workup, radiation therapy, surgical management, and supportive care in PLWH who have cancer.

Progress in central nervous system lymphomas.

Until recently, primary central nervous system lymphoma (PCNSL) was associated with a uniformly dismal prognosis. It is now reasonable to anticipate long-term survival and possibly cure for a significant proportion of patients diagnosed with PCNSL. Accumulated data generated over the past 10 years has provided evidence that long-term progression-free survival (PFS) can reproducibly be attained in a significant fraction of PCNSL patients that receive dose-intensive chemotherapy consolidation, without whole brain radiotherapy. One consolidative regimen that has reproducibly demonstrated promise is the combination of infusional etoposide plus high-dose cytarabine (EA), administered in first complete remission after methotrexate, temozolomide and rituximab-based induction. Given evolving principles of management and the mounting evidence for reproducible improvements in survival rates in prospective clinical series, our goal in this review is to highlight and update principles in diagnosis, staging and management as well as to review data regarding the pathogenesis of central nervous system lymphomas, information that is likely to constitute a basis for the implementation of novel therapies that are requisite for further progress in this unique phenotype of non-Hodgkin lymphoma.

Prevalence of Anal Human Papillomavirus Infection and Anal High-Grade Squamous Intraepithelial Lesions Among Men Who Have Sex With Men 50 Years and Older Living With or Without HIV.

BACKGROUND: Anal cancer is caused by human papillomavirus (HPV), particularly HPV-16, and is preceded by anal high-grade squamous intraepithelial lesions (HSILs). The incidence of anal cancer is highest among men who have sex with men (MSM) living with HIV (MSMLWH) and increases with age. However, most previous studies of anal HPV infection and anal HSIL were performed on men under 50 years old, and relatively little is known about HSIL among older MSMLWH or MSM not living with HIV (MSM-Not-LWH). SETTING: We enrolled MSM who were aged 50+ during 2018-2022 in San Francisco, CA. METHODS: One hundred twenty-nine MSMLWH and 109 MSM-not-LWH participated. All participants had anal HPV DNA testing (Atila Biosystems) and high-resolution anoscopy with a biopsy of visible lesions. RESULTS: Among MSMLWH, 47% had anal HSIL, 19% had HPV-16, and 51% had other oncogenic anal HPV types (excluding HPV-16). Among MSM-not-LWH, 37% had anal HSIL, 22% had HPV-16, and 34% had other oncogenic anal HPV types. Increasing age was not statistically associated with prevalent HSIL, HPV-16, or other oncogenic HPV infections in MSMLWH or MSM-not-LWH. HPV-16 (odds ratio: 45.1, 95% confidence interval: 15.8-129); other oncogenic HPV types (odds ratio: 5.95, 95% confidence interval: 2.74-12.9) were associated with increased odds of anal HSIL, adjusted for age, income, education, and HIV status. CONCLUSION: The prevalence of oncogenic anal HPV, anal HPV-16, and anal HSIL remains very high in older MSMLWH and MSM-not-LWH. With recent evidence showing that treating anal HSIL prevents anal cancer, MSM aged 50+ should be considered for anal cancer screening.

Isolated Pulmonary Arteriovenous Fistula in a Patient with Recurrent Stroke.

UNLABELLED: Paradoxical embolism is a risk factor for cryptogenic stroke in young adults, and can be primarily attributed to the presence of patent foramen ovale (PFO). Although contrast echocardiography may facilitate diagnosis, it would be difficult to distinguish a PFO from a pulmonary arteriovenous fistula (PAVF), which could also result in paradoxical embolism. We report a 46-year-old woman with recurrent ischemic stroke, who was scheduled for PFO closure because of a right-to-left shunt detected by contrast echocardiography. The diagnosis turned out to be a PAVF confirmed by angiography. Thereafter, coil embolization of this PAVF was performed successfully. KEY WORDS: Embolic stroke; Patent foramen ovale; Pulmonary arteriovenous fistula; Right-to-left shunt.

The changing face of HIV in pregnancy in Rhode Island 2004-2009.

Meeting the needs of HIV-infected pregnant women requires understanding their backgrounds and potential barriers to care and safe pregnancy. Foreign-born women are more likely to have language, educational, and economic barriers to care, but may be even more likely to choose to keep a pregnancy. Data from HIV-infected pregnant women and their children in Rhode Island were analyzed to identify trends in demographics, viral control, terminations, miscarriages, timing of diagnosis, and adherence to followup. Between January 2004 and December 2009, 76 HIV-infected women became pregnant, with a total of 95 pregnancies. Seventy-nine percent of the women knew their HIV status prior to becoming pregnant. Fifty-four percent of the women were foreign-born and 38 percent of the 16 women who chose to terminate their pregnancies were foreign-born. While the number of HIV-infected women becoming pregnant has increased only slightly, the proportion that are foreign-born has been rising, from 41 percent between 2004 and 2005 to 57.5 percent between 2006 and 2009. A growing number of women are having multiple pregnancies after their HIV diagnosis, due to the strength of their desire for childbearing and the perception that HIV is a controllable illness that does not preclude the creation of a family.

Adequate Antibody Response to COVID-19 Vaccine in Patients with Monoclonal Gammopathies and Light Chain Amyloidosis.

OBJECTIVE: Determine the COVID-19 seroconversion rate for patients with multiple myeloma receiving a COVID-19 vaccine. MATERIALS AND METHODS: After 45 patients received their second COVID-19 vaccine dose, their serum IgG antibodies were measured: 22 with monoclonal gammopathy (MG) of unknown significance, 3 with smoldering myeloma, 2 with light chain amyloidosis, and 18 with MG (9 in remission, 6 out of remission, and 3 with free light-chain gammopathy alone). A second serum specimen was retained for 16 patients with MG. Their antibody levels were compared to those of 78 uninfected healthy vaccinated control patients. RESULTS: Three patients with MG had low antibody levels on blood collected 98, 100, and 113 days after the initial vaccine dose (2 with MG of unknown significance and 1 with hypogammaglobulemia). The other 40 patients with MG (seroconversion rate 93%) and both patients with amyloidosis produced antibodies. Relative to days after vaccination, patients with MG had lower antibody levels than control patients. CONCLUSION: After receiving a COVID-19 vaccine, most patients with MG produce anti-SARS-CoV-2 antibodies comparable to levels in uninfected vaccinated healthy control patients.

Patterns and Correlates of Changes in Emotional and Behavioral Problems Among Children with Congenital Heart Disease.

OBJECTIVE: The objective of this study was to examine patterns of changes in emotional and behavioral problems among children with congenital heart disease (CHD) and investigate associated factors in different domains. METHOD: The study sample comprised 327 pairs of children with CHD (aged 1.5-12 yrs) and their parents who participated in 2 waves of a survey in Taiwan from 2017 to 2019. The Child Behavior Checklist was used to evaluate the children's emotional and behavioral problems during both waves. The scores were later used to determine the patterns of changes in emotional and behavioral problems. Multinomial logistic regression was then applied to examine factors associated with varied patterns of changes in emotional and behavioral problems. RESULTS: Five patterns of changes in emotional and behavioral problems were identified: "persistent normal," "initial problematic," "worsening," "persistent problematic," and "subclinical." Among the factors examined, parenting stress was consistently associated with different patterns of change in emotional and behavioral problems. Specifically, children with parents who had higher levels of parenting stress were more likely to belong to the "initial problematic," "persistent problematic," or "subclinical" groups than to the "persistent normal" group. Other significant factors included sex, number of surgeries, and perceived health of parents. CONCLUSION: This study highlights the potential role of parenting stress in changes in emotional and behavioral problems. Accordingly, intervention programs aimed at relieving parenting stress may help reduce the development and worsening of emotional and behavioral problems among children with CHD.

Molecular profiling of breast and lung cancer in women with HIV reveals high tumor mutational burden.

OBJECTIVE: This study compared the mutation profile and tumor mutational burden (TMB) in women with HIV (WWH) diagnosed with lung adenocarcinoma (n = 8) or breast ductal neoplasm (n = 13) who were enrolled into the Women's Interagency HIV Study (WIHS). DESIGN: Previous studies tended to focus on single institutions based on sample availability. This study is based on a representative, multicenter cohort that represents the racial and ethnic composition of women with HIV in the United States. METHODS: The study sequenced the complete human exome of n = 26 cancer samples from HIV-positive women, using Ion torrent next-generation sequencing. The study cohort was compared with a HIV-negative cohort obtained from the Genomic Data Commons Data Portal of the NCI. RESULTS: There were no differences in known cancer mutations between breast cancer and lung cancer that developed in WWH and those that developed in HIV-negative (HIV-) women; however, WWH presented a significantly higher TMB in comparison to HIV- patients. Seventy-five percent of lung cancers and 61% of breast cancers were defined as TMB-high (more than 10 mutation/mb of DNA). CONCLUSION: This study affirms the recommendation that WWH be included in clinical trials of novel treatments for these cancers. Although these data are preliminary, the high TMB in WLHV suggests, paradoxically, that this immune challenged population may benefit greatly from immune checkpoint inhibitor therapies.

Exposure to polystyrene microplastics impairs hippocampus-dependent learning and memory in mice.

Microplastics (MPs) pollution has become a serious environmental issue worldwide, but its potential effects on health remain unknown. The administration of polystyrene MPs (PS-MPs) to mice for eight weeks impaired learning and memory behavior. PS-MPs were detected in the brain especially in the hippocampus of these mice. Concurrently, the hippocampus had decreased levels of immediate-early genes, aberrantly enhanced synaptic glutamate AMPA receptors, and elevated neuroinflammation, all of which are critical for synaptic plasticity and memory. Interestingly, ablation of the vagus nerve, a modulator of the gut-brain axis, improved the memory function of PS-MPs mice. These results indicate that exposure to PS-MPs in mice alters the expression of neuronal activity-dependent genes and synaptic proteins, and increases neuroinflammation in the hippocampus, subsequently causing behavioral changes through the vagus nerve-dependent pathway. Our findings shed light on the adverse impacts of PS-MPs on the brain and hippocampal learning and memory.

Pembrolizumab induces HIV latency reversal in people living with HIV and cancer on antiretroviral therapy.

In people living with HIV (PLWH) on antiretroviral therapy (ART), virus persists in a latent form where there is minimal transcription or protein expression. Latently infected cells are a major barrier to curing HIV. Increasing HIV transcription and viral production in latently infected cells could facilitate immune recognition and reduce the pool of infected cells that persist on ART. Given that programmed cell death protein 1 (PD-1) expressing CD4+ T cells are preferentially infected with HIV in PLWH on ART, we aimed to determine whether administration of antibodies targeting PD-1 would reverse HIV latency in vivo. We therefore evaluated the impact of intravenous administration of pembrolizumab every 3 weeks on HIV latency in 32 PLWH and cancer on ART. After the first infusion of anti-PD-1, we observed a median 1.32-fold increase in unspliced HIV RNA and 1.61-fold increase in unspliced RNA:DNA ratio in sorted blood CD4+ T cells compared to baseline. We also observed a 1.65-fold increase in plasma HIV RNA. The frequency of CD4+ T cells with inducible virus evaluated using the tat/rev limiting dilution assay was higher after 6 cycles compared to baseline. Phylogenetic analyses of HIV env sequences in a participant who developed low concentrations of HIV viremia after 6 cycles of pembrolizumab did not demonstrate clonal expansion of HIV-infected cells. These data are consistent with anti-PD-1 being able to reverse HIV latency in vivo and support the rationale for combining anti-PD-1 with other interventions to reduce the HIV reservoir.

Density functional theory study of the oxidation of ammonia on the IrO2(110) surface.

In this study, we employed density functional theory (DFT) to investigate the oxidation of ammonia (NH(3)) on the IrO(2)(110) surface. We characterized the possible reaction pathways for the dehydrogenation of NH(x) species (x = 1-3) and for the formation of the oxidation products N(2), N(2)O, NO, NO(2), and H(2)O. The presence of oxygen atoms on coordinatively unsaturated sites (O(cus)) of the oxygen-rich IrO(2)(110) surface promotes the oxidation of NH(3) on the surface. In contrast, NH(3) molecules prefer undergoing desorption over oxidation on the stoichiometric IrO(2)(110) surface. Moreover, the O(cus) atoms are also the major oxidants leading to the formation of oxidation products; none of the oxidations mediated by the bridge oxygen atoms were favorable reactions. The energy barrier for formation of H(2)O as a gaseous oxidation product on the IrO(2)(110) surface is high (from 1.83 to 2.29 eV), potentially leading to the formation of nitrogen-atom-containing products at high temperature. In addition, the selectivity toward the nitrogen-atom-containing products is dominated by the coverage of O(cus) atoms on the surface; for example, a higher coverage of O(cus) atoms results in greater production of nitrogen oxides (NO, NO(2)).

Use of advanced PET-volume metrics predicts risk of local recurrence and overall survival in anal cancer.

OBJECTIVE: Anal cancer is an uncommon malignancy with the primary treatment for localized disease being concurrent radiation and chemotherapy. Pre-treatment PET/CT is useful for target delineation, with minimal exploration of its use in prognostication. In the post-treatment setting there is growing evidence for advanced PET metrics in assessment of treatment response, and early identification of recurrence essential for successful salvage, however this data is limited to small series. METHODS: Patient with non-metastatic anal cancer from a single institution were retrospectively reviewed for receipt of pre- and post-treatment PET/CTs. PET data was co-registered with radiation therapy planning CT scans for precise longitudinal assessment of advanced PET metrics including SUVmax, metabolic tumor volume (MTV), and total lesion glycolysis (TLG), for assessment with treatment outcomes. Treatment outcomes included local recurrence (LR), progression free survival (PFS), and overall survival (OS), as defined from the completed radiation therapy to the time of the event. Cox proportional hazard modeling with inverse probability weighting (IPW) using the propensity score based on age, BMI, T-stage, and radiation therapy dose were utilized for assessment of these metrics. RESULTS: From 2008 to 2017 there were 72 patients who had pre-treatment PET/CT, 61 (85%) had a single follow up PET/CT, and 35 (49%) had two follow up PET/CTs. The median clinical follow-up time was 25 months (IQR: 13-52) with a median imaging follow up time of 16 months (IQR: 7-29). On pre-treatment PET/CT higher MTV2.5 and TLG were significantly associated with higher risk of local recurrence (HR 1.11, 95% CI: 1.06-1.16, p<0.001; and HR 1.12, 95% CI: 1.05-1.19, p<0.001), and worse PFS (HR 1.09, 95% CI: 1.04-1.13, p<0.001; and HR 1.09, 95% CI: 1.03-1.12, p = 0.003) and OS (HR 1.09, 95% CI: 1.04-1.16, p = 0.001; and HR 1.11, 95% CI: 1.04-1.20, p = 0.004). IPW-adjusted pre-treatment PET/CT showed higher MTV2.5 (HR 1.09, 95% CI: 1.02-1.17, p = 0.012) and TLG (HR 1.10, 95% CI: 1.00-1.20, p = 0.048) were significantly associated with worse PFS, and post-treatment MTV2.5 was borderline significant (HR 1.16, 95% CI: 1.00-1.35, p = 0.052). CONCLUSION: Advanced PET metrics, including higher MTV2.5 and TLG, in the pre-treatment and post-treatment setting are significantly associated with elevated rates of local recurrence, and worse PFS and OS. This adds to the growing body of literature that PET/CT for patient with ASCC should be considered for prognostication, and additionally is a useful tool for consideration of early salvage or clinical trial of adjuvant therapies.