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1.
Aging Cell ; 21(12): e13733, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36281624

ABSTRACT

There is growing interest in the use of metformin to extend lifespan and prevent the onset of age-related disorders in non-diabetic individuals. The impact of metformin on lifespan and aging has been studied in several model organisms, with varying effects. We conducted a systematic review of studies that performed laboratory experiments investigating the effect of metformin on overall lifespan in healthy Mus musculus mice and in Caenorhabditis elegans nematodes. Lifespan results for mice and nematodes were analyzed in separate meta-analyses, and there was a significant amount of heterogeneity across experiments within each species. We found that metformin was not significantly associated with an overall lifespan-prolonging effect in either mice or nematodes. For nematodes, however, there was a lifespan-prolonging effect in experiments using live OP50 Escherichia coli as a food source, an effect that was larger when metformin was started earlier in life. Our work highlights the importance of testing compounds in a diversity of model organisms. Moreover, in all species, including humans, it may be necessary to study the effect of metformin on aging in both younger and older cohorts.


Subject(s)
Caenorhabditis elegans Proteins , Metformin , Humans , Mice , Animals , Caenorhabditis elegans , Metformin/pharmacology , Longevity , Aging
2.
J Clin Epidemiol ; 150: 106-115, 2022 10.
Article in English | MEDLINE | ID: mdl-35777712

ABSTRACT

OBJECTIVES: To assess the patterns and time trends in overall survival and progression-free survival treatment effects across randomized controlled trials (RCTs) in oncology. STUDY DESIGN AND SETTING: A PubMed search for oncology network meta-analyses (NMAs) was carried (to September 30, 2021). Relevant hazard ratios were extracted for systemic treatments from RCTs in the NMAs. After removing duplicate results, relationships between treatment effects, year of publication, trial design, and other features were explored. RESULTS: From 241 oncology NMAs, 2,109 unique eligible RCTs provided analyzable data. On average, there was a 12%-14% reduction in hazard for overall survival and 27%-30% reduction for progression-free survival, with substantial heterogeneity across different malignancies. Correlation between overall survival and progression-free survival treatment effects was modest (r = 0.60, 95% confidence interval, 0.56-0.64). Over time, there was a suggestive trend of increased progression-free survival treatment effect, although overall survival treatment effects remained steady. Only one in five trials met criteria for clinically meaningful improvements in overall survival. Among 300 randomly selected trials, mean absolute improvement was 1.6 months for median progression-free survival and 1.4 months for median overall survival. CONCLUSION: Broad patterns across the past 50 years of oncology research suggest continuous progress has been made, but few results meet clinically meaningful thresholds for overall survival improvement.


Subject(s)
Neoplasms , Randomized Controlled Trials as Topic , Humans , Disease-Free Survival , Neoplasms/therapy , Network Meta-Analysis , Progression-Free Survival
4.
J Clin Epidemiol ; 145: 101-111, 2022 05.
Article in English | MEDLINE | ID: mdl-35091046

ABSTRACT

OBJECTIVE: To analyze distribution of "dramatic", large treatment effects. STUDY DESIGN & SETTING: Pareto distribution modeling of previously reported cohorts of 3,486 randomized trials (RCTs) that enrolled 1,532,459 patients and 730 non-randomized studies (NRS) enrolling 1,650,658 patients. RESULTS: We calculated the Pareto α parameter, which determines the tail of the distribution for various starting points of distribution [odds ratiomin (ORmin)]. In default analysis using all data at ORmin ≥1, Pareto distribution fit well to the treatment effects of RCTs favoring the new treatments (P = 0.21, Kolmogorov-Smirnov test) with best α = 2.32. For NRS, Pareto fit for ORmin ≥2 with best α = 1.91. For RCTs, theoretical 99th percentile OR was 32.7. The actual 99th percentile OR was 25; which converted into relative risk (RR) = 7.1. The maximum observed effect size was OR = 121 (RR = 11.45). For NRS, theoretical 99th percentile was OR = 315. The actual 99th percentile OR was 294 (RR = 13). The maximum observed effect size was OR = 1473 (RR = 66). CONCLUSIONS: The effects sizes observed in RCTs and NRS considerably overlap. Large effects are rare and there is no clear threshold for dramatic effects that would obviate future RCTs.


Subject(s)
Randomized Controlled Trials as Topic , Humans , Odds Ratio
5.
Sex Transm Dis ; 48(12): e192-e201, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34433796

ABSTRACT

BACKGROUND: Bacterial vaginosis (BV) has been associated with an increased risk for acquisition of human immunodeficiency virus and sexually transmitted infections. We evaluated the association between BV and incident Trichomonas vaginalis (TV) infection in women. METHODS: MEDLINE and ClinicalTrials.gov were searched for articles published between January 1, 1980, and May 7, 2021. Observational studies in women that evaluated the relationship between having/not having BV and the risk for acquiring TV were included. RESULTS: Fourteen studies were included in the systematic review; 12 studies were included in meta-analyses involving 18,424 participants. Most studies used Nugent scoring to diagnose BV. For TV diagnosis, 12 studies used wet mount microscopy or culture, and 2 used nucleic acid amplification tests. There was diversity in the measures of association used, so an overall effect size could not be calculated. The majority of studies reported odds ratios, which showed an increased risk of incident TV among women with BV versus without BV (adjusted odds ratio, 1.87; 95% confidence interval, 1.45-2.40; P = 0.007). However, there were heterogeneity and potential confounding factors (eg, age, sexual partners) reported among studies. CONCLUSIONS: This systematic review and meta-analysis provide evidence for a nearly 2-fold higher risk for acquiring TV among women with BV compared with women without BV.


Subject(s)
Trichomonas Infections , Trichomonas Vaginitis , Trichomonas vaginalis , Vaginosis, Bacterial , Female , Humans , Trichomonas Infections/epidemiology , Trichomonas Vaginitis/complications , Trichomonas Vaginitis/epidemiology , Vagina , Vaginosis, Bacterial/epidemiology
6.
Life (Basel) ; 11(8)2021 Jul 22.
Article in English | MEDLINE | ID: mdl-34440474

ABSTRACT

Identifying prognostic biomarkers and risk stratification for COVID-19 patients is a challenging necessity. One of the core survival factors is patient age. However, chronological age is often severely biased due to dormant conditions and existing comorbidities. In this retrospective cohort study, we analyzed the data from 5315 COVID-19 patients (1689 lethal cases) admitted to 11 public hospitals in New York City from 1 March 2020 to 1 December. We calculated patients' pace of aging with BloodAge-a deep learning aging clock trained on clinical blood tests. We further constructed survival models to explore the prognostic value of biological age compared to that of chronological age. A COVID-19 score was developed to support a practical patient stratification in a clinical setting. Lethal COVID-19 cases had higher predicted age, compared to non-lethal cases (Δ = 0.8-1.6 years). Increased pace of aging was a significant risk factor of COVID-related mortality (hazard ratio = 1.026 per year, 95% CI = 1.001-1.052). According to our logistic regression model, the pace of aging had a greater impact (adjusted odds ratio = 1.09 ± 0.00, per year) than chronological age (1.04 ± 0.00, per year) on the lethal infection outcome. Our results show that a biological age measure, derived from routine clinical blood tests, adds predictive power to COVID-19 survival models.

7.
Acad Emerg Med ; 28(12): 1379-1388, 2021 12.
Article in English | MEDLINE | ID: mdl-34133813

ABSTRACT

OBJECTIVES: The objective of this study was to conduct an umbrella review of therapeutic studies relevant to emergency medicine, analyzing patterns in effect size, power, and signals of potential bias across an entire field of clinical research. METHODS: We combined topic- and journal-driven searches of PubMed and Google Scholar for published articles of systematic reviews and meta-analyses (SRMA) relevant to emergency medicine (last search in November 2020). Data were screened and extracted by six investigators. Redundant meta-analyses were removed. Whenever possible for each comparison we extracted one meta-analysis on mortality with the most events and one meta-analysis on a nonmortality outcome with the most studies. From each meta-analysis we extracted all individual study effects; outcomes were converted to odds ratios (ORs) and placed on a common scale where an OR < 1.0 represents a reduction in a harmful outcome with an experimental treatment versus control. Outcomes were analyzed at the level of individual studies and at the level of summary effects across meta-analyses. RESULTS: A total of 332 articles contained 431 eligible meta-analyses with a total of 3,129 individual study outcomes; of these, 2,593 (83%) were from randomized controlled trials. The median OR across all studies was 0.70. Within each meta-analysis, the earliest study effect on average demonstrated larger benefit compared to the overall summary effect. Only 57 of 431 meta-analyses (13%) both favored the experimental intervention and did not show any signal of small study effects or excess significance, and of those only 12 had at least one study with 80% or higher power to detect an OR of 0.70. Of these, no interventions significantly decreased mortality in well-powered trials. Although the power of studies increased somewhat over time, the majority of studies were underpowered. CONCLUSIONS: Few interventions studied within SRMAs relevant to emergency medicine seem to have strong and unbiased evidence for improving outcomes. The field would benefit from more optimally powered trials.


Subject(s)
Emergency Medicine , Humans , Odds Ratio , Randomized Controlled Trials as Topic , Systematic Reviews as Topic
8.
Crit Care Explor ; 3(6): e0452, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34151281

ABSTRACT

OBJECTIVES: There has been controversy about the timing and indications for intubation and mechanical ventilation in novel coronavirus disease 2019. This study assessed the effect of early intubation and mechanical ventilation on all-cause, inhospital mortality for coronavirus disease 2019 patients. DESIGN: Multicenter retrospective cohort study. SETTING: Eleven municipal hospitals in New York City from March 1, 2020, to December 1, 2020. PATIENTS: Adult patients who tested positive for coronavirus disease 2019 in the emergency department were subsequently admitted. Patients with do-not-intubate orders at admission were excluded. INTERVENTIONS: Intubation within 48 hours of triage and intubation at any point during hospital stay. MEASUREMENTS AND MAIN RESULTS: Data from 7,597 coronavirus disease 2019 patients were included; of these, 1,628 (21%) were intubated overall and 807 (11%) were intubated within 48 hours of triage. After controlling for available confounders, intubation rates for coronavirus disease 2019 patients varied significantly across hospitals and decreased steadily as the pandemic progressed. After nearest neighbor propensity score matching, intubation within 48 hours of triage was associated with higher all-cause mortality (hazard ratio, 1.30 [1.15-1.48]; p < 0.0001), as was intubation at any time point (hazard ratio, 1.62 [1.45-1.80]; p < 0.0001). Among intubated patients, intubation within 48 hours of triage was not significantly associated with differences in mortality (hazard ratio, 1.09 [0.94-1.26]; p = 0.26). These results remained robust to multiple sensitivity analyses. CONCLUSIONS: Intubation within 48 hours of triage, as well as at any time point in the hospital course, was associated with increased mortality in coronavirus disease 2019 patients in this observational study.

9.
Front Pediatr ; 8: 384, 2020.
Article in English | MEDLINE | ID: mdl-32766186

ABSTRACT

Objective: To characterize the clinical presentation and outcomes of Kawasaki disease (KD) in infants <6 months of age as compared to those ≥6 months in Latin America. Methods: We evaluated 36 infants <6 months old and 940 infants ≥6 months old diagnosed with KD in Latin America. We compared differences in laboratory data, clinical presentation, treatment response, and coronary artery outcomes between the two cohorts. Results: The majority (78.1%) of infants and children ≥6 months of age were initially diagnosed with KD, as compared to only 38.2% of infants <6 months. Clinical features of KD were more commonly observed in the older cohort: oral changes (92 vs. 75%, P = 0.0023), extremity changes (74.6 vs. 57.1%, P = 0.029), and cervical lymphadenopathy (67.6 vs. 37.1%, P = 0.0004). Whether treated in the first 10 days of illness or after the 10th day, infants <6 months were at greater risk of developing a coronary artery aneurysm compared to KD patients ≥6 months treated at the same point in the course of illness [ ≤ 10 days (53.8 vs. 9.4%, P = 0.00012); >10 days (50 vs. 7.4%, P = 0.043)]. Conclusion: Our data show that despite treatment in the first 10 days of illness, infants <6 months of age in Latin America have a higher risk of developing a coronary artery aneurysm. Delay in the diagnosis leads to larger coronary artery aneurysms disproportionately in these infants. Thus, suspicion for KD should be high in this vulnerable population.

10.
Cancer ; 124(20): 4080-4089, 2018 10 15.
Article in English | MEDLINE | ID: mdl-30204251

ABSTRACT

BACKGROUND: Advances in deep sequencing technology have uncovered a widespread, protumorigenic role of guanine nucleotide-binding (G protein) α (GNA) subunits, particularly GNA subunits Gs (GNAS), Gq (GNAQ), and G11 (GNA11) (GNA*), in a diverse collection of malignancies. The objectives of the current study were: 1) to determine GNA* aberration status in a cohort of 1348 patients with cancer and 2) to examine tumor mutational burden, overall survival rates, and treatment outcomes in patients with GNA*-positive tumors versus those with tumors that had wild-type GNA*. METHODS: For each patient, clinical and genomic data were collected from medical records. Next-generation sequencing was performed for each patient (range, 182-236 genes). RESULTS: Aberrations of GNA* genes were identified in a subset of patients who had 8 of the 12 cancer types examined, and a significant association was observed for appendiceal cancer and ocular melanoma (P < .0001 for both; multivariate analysis). Overall, 4.1% of the cancer population was affected. GNA* abnormalities were associated with higher numbers of co-alterations in univariate (but not multivariate) analysis and were most commonly accompanied by Aurora kinase A (AURKA), Cbl proto-oncogene (CBL), and LYN proto-oncogene (LYN) co-alterations (all P < .0001; multivariate analysis). GNA* alterations were correlated with a trend toward lower median overall survival (P = .085). The median tumor mutational burden was 4 mutations per megabase in both GNA*-altered and GNA* wild-type tumors. For this limited sample of GNA*-positive patients, longer survival was not correlated with any specific treatment regimens. CONCLUSIONS: In the current sample, the genes GNAS, GNAQ, and GNA11 were widely altered across cancer types, and these alterations often were accompanied by specific genomic abnormalities in AURKA, CBL, and LYN. Therefore, targeting GNA* alterations may require drugs that address the GNA* signal and important co-alterations. Cancer 2018;00:000-000. © 2018 American Cancer Society.


Subject(s)
Chromogranins/genetics , GTP-Binding Protein alpha Subunits, Gq-G11/genetics , GTP-Binding Protein alpha Subunits, Gs/genetics , GTP-Binding Protein alpha Subunits/genetics , Neoplasms/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cohort Studies , DNA Mutational Analysis/methods , Female , Genetic Association Studies , Genetic Predisposition to Disease , High-Throughput Nucleotide Sequencing , Humans , Infant , Male , Middle Aged , Mutation , Neoplasms/classification , Neoplasms/mortality , Proto-Oncogene Mas , Retrospective Studies , Young Adult
11.
PLoS One ; 13(1): e0189742, 2018.
Article in English | MEDLINE | ID: mdl-29320509

ABSTRACT

We aimed to assess which factors correlate with collaborative behavior and whether such behavior associates with scientific impact (citations and becoming a principal investigator). We used the R index which is defined for each author as log(Np)/log(I1), where I1 is the number of co-authors who appear in at least I1 papers written by that author and Np are his/her total papers. Higher R means lower collaborative behavior, i.e. not working much with others, or not collaborating repeatedly with the same co-authors. Across 249,054 researchers who had published ≥30 papers in 2000-2015 but had not published anything before 2000, R varied across scientific fields. Lower values of R (more collaboration) were seen in physics, medicine, infectious disease and brain sciences and higher values of R were seen for social science, computer science and engineering. Among the 9,314 most productive researchers already reaching Np ≥ 30 and I1 ≥ 4 by the end of 2006, R mostly remained stable for most fields from 2006 to 2015 with small increases seen in physics, chemistry, and medicine. Both US-based authorship and male gender were associated with higher values of R (lower collaboration), although the effect was small. Lower values of R (more collaboration) were associated with higher citation impact (h-index), and the effect was stronger in certain fields (physics, medicine, engineering, health sciences) than in others (brain sciences, computer science, infectious disease, chemistry). Finally, for a subset of 400 U.S. researchers in medicine, infectious disease and brain sciences, higher R (lower collaboration) was associated with a higher chance of being a principal investigator by 2016. Our analysis maps the patterns and evolution of collaborative behavior across scientific disciplines.


Subject(s)
Authorship , Efficiency , Research
12.
Bioconjug Chem ; 21(3): 476-82, 2010 Mar 17.
Article in English | MEDLINE | ID: mdl-20146456

ABSTRACT

Eu(III) complexes of DNA containing a non-nucleosidic linker, a derivative of 1,10-phenanthroline-2,6-dicarboxamide (Q), are studied with the goal of forming novel lanthanide ion binding sites that are incorporated in the backbone of DNA. One oligonucleotide is short and unstructured (TTTQTTT (QT6)) and the other (5'-AGCTCGGTCAQCGAGAGTGCA-3' (SQ)) is studied both in single-stranded form and in the presence of a partially complementary DNA strand. Luminescence spectroscopy studies show that Eu(III) binds to SQ, QT6, AQB, or QB 1100-, 56-, 23-, or 27-fold more tightly, respectively, than to a simple 1,10-phenanthroline-2,6-dicarboxamide ligand (Q1). Direct excitation and phenanthroline sensitized luminescence spectroscopy supports binding of Eu(III) to the phenanthroline linker in QT6 and in double-stranded DNA formed from SQ and partially complementary sequences that place Q in a bulge-like position. Eu(III) hydration numbers range from 3 to 5 when bound to the phenanthroline moiety in modified DNA, consistent with binding to the tetradentate linker and, in some cases, coordination to other groups in the DNA. Thermal melting experiments show that Q in a bulge-like structure stabilizes double-stranded DNA and that Eu(III) binding does not markedly affect the stability of the duplex.


Subject(s)
DNA/chemistry , Europium/chemistry , Organometallic Compounds/chemistry , Phenanthrolines/chemistry , Binding Sites , Molecular Conformation , Organometallic Compounds/chemical synthesis
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