Deaths of U.S. Citizens Undergoing Cosmetic Surgery - Dominican Republic, 2009-2022.

Although infections resulting from cosmetic surgery performed outside the United States have been regularly reported, deaths have rarely been identified. During 2009-2022, 93 U.S. citizens died after receiving cosmetic surgery in the Dominican Republic. The number of deaths increased from a mean of 4.1 per year during 2009-2018 to a mean of 13.0 during 2019-2022 with a peak in of 17 in 2020. A subset of post-cosmetic surgery deaths occurring during peak years was investigated, and most deaths were found to be the result of embolic events (fat emboli or venous thromboembolism) for which a high proportion of the patients who died had risk factors, including obesity and having multiple procedures performed during the same operation. These risk factors might have been mitigated or prevented with improved surgical protocols and postoperative medical care, including prophylactic measures against venous thromboembolism. U.S. citizens interested in receiving elective cosmetic surgery outside the United States should consult with their health care professionals regarding their risk for adverse outcomes. Public health authorities can support provider education on the importance of preoperative patient evaluation and the potential danger of performing multiple cosmetic procedures in one operation.

Nonlinear Charge Transport and Excitable Phenomena in Semiconductor Superlattices.

Semiconductor superlattices are periodic nanostructures consisting of epitaxially grown quantum wells and barriers. For thick barriers, the quantum wells are weakly coupled and the main transport mechanism is a sequential resonant tunneling of electrons between wells. We review quantum transport in these materials, and the rate equations for electron densities, currents, and the self-consistent electric potential or field. Depending on superlattice configuration, doping density, temperature, voltage bias, and other parameters, superlattices behave as excitable systems, and can respond to abrupt dc bias changes by large transients involving charge density waves before arriving at a stable stationary state. For other parameters, the superlattices may have self-sustained oscillations of the current through them. These oscillations are due to repeated triggering and recycling of charge density waves, and can be periodic in time, quasiperiodic, and chaotic. Modifying the superlattice configuration, it is possible to attain robust chaos due to wave dynamics. External noise of appropriate strength can generate time-periodic current oscillations when the superlattice is in a stable stationary state without noise, which is called the coherence resonance. In turn, these oscillations can resonate with a periodic signal in the presence of sufficient noise, thereby displaying a stochastic resonance. These properties can be exploited to design and build many devices. Here, we describe detectors of weak signals by using coherence and stochastic resonance and fast generators of true random sequences useful for safe communications and storage.

Scale-Free Chaos in the 2D Harmonically Confined Vicsek Model.

Animal motion and flocking are ubiquitous nonequilibrium phenomena that are often studied within active matter. In examples such as insect swarms, macroscopic quantities exhibit power laws with measurable critical exponents and ideas from phase transitions and statistical mechanics have been explored to explain them. The widely used Vicsek model with periodic boundary conditions has an ordering phase transition but the corresponding homogeneous ordered or disordered phases are different from observations of natural swarms. If a harmonic potential (instead of a periodic box) is used to confine particles, then the numerical simulations of the Vicsek model display periodic, quasiperiodic, and chaotic attractors. The latter are scale-free on critical curves that produce power laws and critical exponents. Here, we investigate the scale-free chaos phase transition in two space dimensions. We show that the shape of the chaotic swarm on the critical curve reflects the split between the core and the vapor of insects observed in midge swarms and that the dynamic correlation function collapses only for a finite interval of small scaled times. We explain the algorithms used to calculate the largest Lyapunov exponents, the static and dynamic critical exponents, and compare them to those of the three-dimensional model.

Lessons Learned from Programmatic Gains in HIV Service Delivery During the COVID-19 Pandemic - 41 PEPFAR-Supported Countries, 2020.

The U.S. President's Emergency Plan for AIDS Relief (PEPFAR) supports country programs in identifying persons living with HIV infection (PLHIV), providing life-saving treatment, and reducing the spread of HIV in countries around the world (1,2). CDC used Monitoring, Evaluation, and Reporting (MER) data* to assess the extent to which COVID-19 mitigation strategies affected HIV service delivery across the HIV care continuum† globally during the first year of the COVID-19 pandemic. Indicators included the number of reported HIV-positive test results, the number of PLHIV who were receiving antiretroviral therapy (ART), and the rates of HIV viral load suppression. Percent change in performance was assessed between countries during the first 3 months of 2020, before COVID-19 mitigation efforts began (January-March 2020), and the last 3 months of the calendar year (October-December 2020). Data were reviewed for all 41 countries to assess total and country-level percent change for each indicator. Then, qualitative data were reviewed among countries in the upper quartile to assess specific strategies that contributed to programmatic gains. Overall, positive percent change was observed in PEPFAR-supported countries in HIV treatment (5%) and viral load suppression (2%) during 2020. Countries reporting the highest gains across the HIV care continuum during 2020 attributed successes to reducing or streamlining facility attendance through strategies such as enhancing index testing (offering of testing to the biologic children and partners of PLHIV)§ and community- and home-based testing; treatment delivery approaches; and improvements in data use through monitoring activities, systems, and data quality checks. Countries that reported program improvements during the first year of the COVID-19 pandemic offer important information about how lifesaving HIV treatment might be provided during a global public health crisis.

Hospital Arrival and Functional Outcome after Intracerebral Hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is associated with an ominous outcome influenced by the time to hospital presentation. OBJECTIVE: This study aims to identify the factors that influence an early hospital arrival after ICH and the relationship with outcome. METHODS: In this multicenter registry, patients with confirmed ICH on CT scan and well-known time of symptoms onset were studied. Clinical data, arrival conditions, and prognostic scores were analyzed. Multivariate models were built to find independent predictors of < 6 h arrival (logistic regression) and in-hospital death (Cox proportional-hazards model). RESULTS: Among the 473 patients analyzed (51% women, median age 63 years), the median delay since onset to admission was 6.25 h (interquartile range: 2.5-24 h); 7.8% arrived in < 1 h, 26.3% in < 3 h, 45.3% in < 6 h, and 62.3% in < 12 h. The in-hospital, 30-day and 90-day case fatality rates were 28.8%, 30.0%, and 32.6%, respectively. Predictors of arrival in < 6 h were hypertension treatment (odds ratios [OR]: 1.675, 95% confidence intervals [CI]: 1.030-2.724), ≥ 3 years of schooling (OR: 1.804, 95% CI: 1.055-3.084), and seizures at ICH onset (OR: 2.416, 95% CI: 1.068-5.465). Predictors of death (56.9% neurological) were systolic blood pressure > 180 mmHg (hazards ratios [HR]: 1.839, 95% CI: 1.031-3.281), ICH score ≥ 3 (HR: 2.302, 95% CI: 1.300-4.074), and admission Glasgow Coma Scale < 8 (HR: 4.497, 95% CI: 2.466-8.199). Early arrival was not associated with outcome at discharge, 30 or 90 days. CONCLUSIONS: In this study, less than half of patients with ICH arrived to the hospital in < 6 h. However, early arrival was not associated with the short-term outcome in this data set.

Hyperchaos, Intermittency, Noise and Disorder in Modified Semiconductor Superlattices.

Weakly coupled semiconductor superlattices under DC voltage bias are nonlinear systems with many degrees of freedom whose nonlinearity is due to sequential tunneling of electrons. They may exhibit spontaneous chaos at room temperature and act as fast physical random number generator devices. Here we present a general sequential transport model with different voltage drops at quantum wells and barriers that includes noise and fluctuations due to the superlattice epitaxial growth. Excitability and oscillations of the current in superlattices with identical periods are due to nucleation and motion of charge dipole waves that form at the emitter contact when the current drops below a critical value. Insertion of wider wells increases superlattice excitability by allowing wave nucleation at the modified wells and more complex dynamics. Then hyperchaos and different types of intermittent chaos are possible on extended DC voltage ranges. Intrinsic shot and thermal noises and external noises produce minor effects on chaotic attractors. However, random disorder due to growth fluctuations may suppress any regular or chaotic current oscillations. Numerical simulations show that more than 70% of samples remain chaotic when the standard deviation of their fluctuations due to epitaxial growth is below 0.024 nm (10% of a single monolayer) whereas for 0.015 nm disorder suppresses chaos.

Phosphorylation-dependent control of an RNA granule-localized protein that fine-tunes defence gene expression at a post-transcriptional level.

Mitogen-activated protein kinase (MAPK) cascades are key signalling modules of plant defence responses to pathogen-associated molecular patterns [PAMPs; e.g. the bacterial peptide flagellin (flg22)]. Tandem zinc finger protein 9 (TZF9) is a RNA-binding protein that is phosphorylated by two PAMP-responsive MAPKs, MPK3 and MPK6. We mapped the major phosphosites in TZF9 and showed their importance for controlling in vitro RNA-binding activity, in vivo flg22-induced rapid disappearance of TZF9-labelled processing body-like structures and TZF9 protein turnover. Microarray analysis showed a strong discordance between transcriptome (total mRNA) and translatome (polysome-associated mRNA) in the tzf9 mutant, with more mRNAs associated with ribosomes in the absence of TZF9. This suggests that TZF9 may sequester and inhibit the translation of subsets of mRNAs. Fittingly, TZF9 physically interacts with poly(A)-binding protein 2 (PAB2), a hallmark constituent of stress granules - sites for stress-induced translational stalling/arrest. TZF9 even promotes the assembly of stress granules in the absence of stress. Hence, MAPKs may control defence gene expression post-transcriptionally through release from translation arrest within TZF9-PAB2-containing RNA granules or by perturbing the function of PAB2 in translation control (e.g. in the mRNA closed-loop model of translation).

Kovacs Memory Effect with an Optically Levitated Nanoparticle.

The understanding of the dynamics of nonequilibrium cooling and heating processes at the nanoscale is still an open problem. These processes can follow surprising relaxation paths due to, e.g., memory effects, which significantly alter the expected equilibration routes. The Kovacs effect can take place when a thermalization process is suddenly interrupted by a change of the bath temperature, leading to a nonmonotonic evolution of the energy of the system. Here, we demonstrate that the Kovacs effect can be observed in the thermalization of the center of mass motion of a levitated nanoparticle. The temperature is controlled during the experiment through an external source of white Gaussian noise that mimics an effective thermal bath at a temperature that can be changed faster than any relaxation time of the system. We describe our experiments in terms of the dynamics of a Brownian particle in a harmonic trap without any fitting parameter, suggesting that the Kovacs effect can appear in a large variety of systems.

Tracking collective cell motion by topological data analysis.

By modifying and calibrating an active vertex model to experiments, we have simulated numerically a confluent cellular monolayer spreading on an empty space and the collision of two monolayers of different cells in an antagonistic migration assay. Cells are subject to inertial forces and to active forces that try to align their velocities with those of neighboring ones. In agreement with experiments in the literature, the spreading test exhibits formation of fingers in the moving interfaces, there appear swirls in the velocity field, and the polar order parameter and the correlation and swirl lengths increase with time. Numerical simulations show that cells inside the tissue have smaller area than those at the interface, which has been observed in recent experiments. In the antagonistic migration assay, a population of fluidlike Ras cells invades a population of wild type solidlike cells having shape parameters above and below the geometric critical value, respectively. Cell mixing or segregation depends on the junction tensions between different cells. We reproduce the experimentally observed antagonistic migration assays by assuming that a fraction of cells favor mixing, the others segregation, and that these cells are randomly distributed in space. To characterize and compare the structure of interfaces between cell types or of interfaces of spreading cellular monolayers in an automatic manner, we apply topological data analysis to experimental data and to results of our numerical simulations. We use time series of data generated by numerical simulations to automatically group, track and classify the advancing interfaces of cellular aggregates by means of bottleneck or Wasserstein distances of persistent homologies. These techniques of topological data analysis are scalable and could be used in studies involving large amounts of data. Besides applications to wound healing and metastatic cancer, these studies are relevant for tissue engineering, biological effects of materials, tissue and organ regeneration.

Notch signaling and taxis mechanisms regulate early stage angiogenesis: A mathematical and computational model.

During angiogenesis, new blood vessels sprout and grow from existing ones. This process plays a crucial role in organ development and repair, in wound healing and in numerous pathological processes such as cancer progression or diabetes. Here, we present a mathematical model of early stage angiogenesis that permits exploration of the relative importance of mechanical, chemical and cellular cues. Endothelial cells proliferate and move over an extracellular matrix by following external gradients of Vessel Endothelial Growth Factor, adhesion and stiffness, which are incorporated to a Cellular Potts model with a finite element description of elasticity. The dynamics of Notch signaling involving Delta-4 and Jagged-1 ligands determines tip cell selection and vessel branching. Through their production rates, competing Jagged-Notch and Delta-Notch dynamics determine the influence of lateral inhibition and lateral induction on the selection of cellular phenotypes, branching of blood vessels, anastomosis (fusion of blood vessels) and angiogenesis velocity. Anastomosis may be favored or impeded depending on the mechanical configuration of strain vectors in the ECM near tip cells. Numerical simulations demonstrate that increasing Jagged production results in pathological vasculatures with thinner and more abundant vessels, which can be compensated by augmenting the production of Delta ligands.

Fingering instability in spreading epithelial monolayers: roles of cell polarisation, substrate friction and contractile stresses.

Collective cell migration plays a crucial role in many developmental processes that underlie morphogenesis, wound healing, or cancer progression. In such coordinated behaviours, cells are organised in coherent structures and actively migrate to serve different biological purposes. In some contexts, namely during epithelial wound healing, it is well known that a migrating free-edge monolayer develops finger-like instabilities, yet the onset is still under debate. Here, by means of theory and numerical simulations, we shed light on the main mechanisms driving the instability process, analysing the linear and nonlinear dynamics of a continuum compressible polar fluid. In particular, we assess the role of cell polarisation, substrate friction, and contractile stresses. Linear theory shows that it is crucial to analyse the perturbation transient dynamics, since we unravel a plethora of crossovers between different exponential growth rates during the linear regime. Numerical simulations suggest that cell-substrate friction could be the mechanism responsible for the formation of complex finger-like structures at the edge, since it triggers secondary fingering instabilities and tip-splitting phenomena. Finally, we obtain a critical contractile stress that depends on cell-substrate friction and the initial-to-nematic length ratio, characterising an active wetting-dewetting transition. In the dewetting scenario, the monolayer retracts and becomes stable without developing finger-like structures.

Outbreak of Severe Histoplasmosis Among Tunnel Workers-Dominican Republic, 2015.

Background: Histoplasmosis is a fungal infection associated with exposure to bat guano. An outbreak of an unknown severe febrile illness occurred among tunnel workers in the Dominican Republic, and resulted in several deaths. We conducted an investigation to confirm etiology and recommend control measures. Methods: A case was defined as fever and ≥2 symptoms consistent with histoplasmosis in a tunnel worker, July-September 2015. We interviewed workers and family members, reviewed medical records, tested serum and urine for Histoplasma antigen/antibody, and conducted a cohort study to identify risk factors for histoplasmosis and severe infection (intensive care). Results: A crew of 36 male workers removed large amounts of bat guano from tunnels without respiratory protection for a median of 24 days per worker (range, 1-25 days). Median age was 32 years (range, 18-62 years); none were immunocompromised. Thirty (83%) workers had illness that met the case definition, of whom 28 (93%) were hospitalized, 9 (30%) required intensive care, 6 (20%) required intubation, and 3 (10%) died. The median time from symptom onset to antifungal treatment was 6 days (range, 1-11 days). Twenty-two of 34 (65%) workers had laboratory evidence of infection. Conclusions: Severe illnesses and death likely resulted from exposure to large inocula of Histoplasma capsulatum spores in an enclosed space, lack of respiratory protection, and delay in recognition and treatment. Clinician education about histoplasmosis, improved laboratory capacity to diagnose fungal infections, and occupational health guidance to protect workers against endemic fungi are recommended in the Dominican Republic.

Coherence Resonance and Stochastic Resonance in an Excitable Semiconductor Superlattice.

Collective electron transport causes a weakly coupled semiconductor superlattice under dc voltage bias to be an excitable system with 2N+2 degrees of freedom: electron densities and fields at N superlattice periods plus the total current and the field at the injector. External noise of sufficient amplitude induces regular current self-oscillations (coherence resonance) in states that are stationary in the absence of noise. Numerical simulations show that these oscillations are due to the repeated nucleation and motion of charge dipole waves that form at the emitter when the current falls below a critical value. At the critical current, the well-to-well tunneling current intersects the contact load line. We have determined the device-dependent critical current for the coherence resonance from experiments and numerical simulations. We have also described through numerical simulations how a coherence resonance triggers a stochastic resonance when its oscillation mode becomes locked to a weak ac external voltage signal. Our results agree with the experimental observations.

Fast Detection of a Weak Signal by a Stochastic Resonance Induced by a Coherence Resonance in an Excitable GaAs/Al_{0.45}Ga_{0.55}As Superlattice.

The effect of a coherence resonance is observed experimentally in a GaAs/Al_{0.45}Ga_{0.55}As superlattice under dc bias at room temperature, which is driven by noise. For an applied voltage, for which no current self-oscillations are observed, regular current self-oscillations with a frequency of about 82 MHz are induced by exceeding a certain noise amplitude. In addition, a novel kind of a stochastic resonance is identified, which is triggered by the coherence resonance. This stochastic resonance appears when the device is driven by an external ac signal with a frequency, which is relatively close to that of the regular current self-oscillations at the coherence resonance. The intrinsic oscillation mode in the coherence resonance is found to be phase locked by an extremely weak ac signal. It is demonstrated that an excitable superlattice device can be used for the fast detection of weak signals submerged in noise. These results are very well reproduced by results using numerical simulations based on a sequential resonant tunneling model of nonlinear electron transport in semiconductor superlattices.

Parameter dependence of high-frequency nonlinear oscillations and intrinsic chaos in short GaAs/(Al, Ga)As superlattices.

We explore the design parameter space of short (5-25 period), n-doped, Ga/(Al,Ga)As semiconductor superlattices (SSLs) in the sequential resonant tunneling regime. We consider SSLs at cool (77 K) and warm (295 K) temperatures, simulating the electronic response to variations in (a) the number of SSL periods, (b) the contact conductivity, and (c) the strength of disorder (aperiodicities). Our analysis shows that the chaotic dynamical phases exist on a number of sub-manifolds of codimension zero within the design parameter space. This result provides an encouraging guide towards the experimental observation of high-frequency intrinsic dynamical chaos in shorter SSLs.

Public and Private Hospital Care Disparities of Ischemic Stroke in Mexico: Results from the Primer Registro Mexicano de Isquemia Cerebral (PREMIER) Study.

BACKGROUND AND AIMS: Mortality and bad outcome by stroke are higher in developing countries than in industrialized countries. Health-care system efficiency could explain these disparities. Our objective was to identify the impact on short- and middle-term outcomes of patients with acute ischemic stroke (AIS) among public and private Mexican medical care. METHODS: We analyzed data from patients with AIS included in the Primer Registro Mexicano de Isquemia Cerebral (PREMIER) study. Transient ischemic attacks (TIAs) and ambulatory patients were excluded. Mortality and good outcome were assessed by the modified Rankin Scale (mRS) and analyzed at 1, 3, and 12 months of follow-up. RESULTS: From 1246 patients with AIS included in the registry, 1123 were hospitalized, either in public (n = 881) or in private (n = 242) hospitals. There were no significant differences regarding age and gender. In private settings, patients had a higher educational level, a major frequency of dyslipidemia, a previous stroke and TIA, less overweight and obesity, a sedentary lifestyle, and diabetes; stroke severity, the rate of systemic complications, the length of stay, and in-hospital mortality were also lower; a major frequency of thrombolysis was observed when compared with public hospitals. Our study showed a better outcome (mRS score ≤2) in private scenarios and a higher mortality in patients treated in public hospitals at short- and middle-term follow-ups. CONCLUSIONS: A polarized medical practice was observed in the AIS care in this large multicenter cohort of Mexico. There is evidence of an advantage for private scenarios, possibly related with an optimal infrastructure or with a strong patient's economic status.

Associations of HIV Testing, Sexual Risk and Access to Prevention Among Female Sex Workers in the Dominican Republic.

The Caribbean region has one of the highest proportions of HIV in the general female population attributable to sex work. In 2008 (n = 1256) and 2012 (n = 1525) in the Dominican Republic, HIV biological and behavioral surveys were conducted among female sex workers (FSW) in four provinces using respondent driven sampling. Participants were ≥15 years who engaged in intercourse in exchange for money in the past 6 months and living/working in the study province. There were no statistically significant changes in HIV and other infections prevalence from 2008 to 2012, despite ongoing risky sexual practices. HIV testing and receiving results was low in all provinces. FSW in 2012 were more likely to receive HIV testing and results if they participated in HIV related information and education and had regular checkups at health centers. Further investigation is needed to understand barriers to HIV testing and access to prevention services.

Demographic and clinical characteristics of deaths associated with influenza A(H1N1) pdm09 in Central America and Dominican Republic 2009-2010.

BACKGROUND: The demographic characteristics of pandemic influenza decedents among middle and low-income tropical countries are poorly understood. We explored the demographics of persons who died with influenza A (H1N1)pdm09 infection during 2009-2010, in seven countries in the American tropics. METHODS: We used hospital-based surveillance to identify laboratory-confirmed influenza deaths in Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama and Dominican Republic. An influenza death was defined as a person who died within two weeks of a severe acute respiratory infection (SARI) defined as sudden onset of fever >38 °C, cough or sore-throat, and shortness of breath, or difficulty breathing requiring hospitalization, and who tested positive for influenza A (H1N1)pdm09 virus by real time polymerase chain reaction. We abstracted the demographic and clinical characteristics of the deceased from their medical records. RESULTS: During May 2009-June 2010, we identified 183 influenza deaths. Their median age was 32 years (IQR 18-46 years). One-hundred and one (55 %) were female of which 20 (20 %) were pregnant and 7 (7 %) were in postpartum. One-hundred and twelve decedents (61 %) had pre-existing medical conditions, (15 % had obesity, 13 % diabetes, 11 % asthma, 8 % metabolic disorders, 5 % chronic obstructive pulmonary disease, and 10 % neurological disorders). 65 % received oseltamivir but only 5 % received it within 48 h of symptoms onset. CONCLUSIONS: The pandemic killed young adults, pregnant women and those with pre-existing medical conditions. Most sought care too late to fully benefit from oseltamivir. We recommend countries review antiviral treatment policies for people at high risk of developing complications.

The Arabidopsis tandem zinc finger 9 protein binds RNA and mediates pathogen-associated molecular pattern-triggered immune responses.

Recognition of pathogen-associated molecular patterns (PAMPs) induces multiple defense mechanisms to limit pathogen growth. Here, we show that the Arabidopsis thaliana tandem zinc finger protein 9 (TZF9) is phosphorylated by PAMP-responsive mitogen-activated protein kinases (MAPKs) and is required to trigger a full PAMP-triggered immune response. Analysis of a tzf9 mutant revealed attenuation in specific PAMP-triggered reactions such as reactive oxygen species accumulation, MAPK activation and, partially, the expression of several PAMP-responsive genes. In accordance with these weaker PAMP-triggered responses, tzf9 mutant plants exhibit enhanced susceptibility to virulent Pseudomonas syringae pv. tomato DC3000. Visualization of TZF9 localization by fusion to green fluorescent protein revealed cytoplasmic foci that co-localize with marker proteins of processing bodies (P-bodies). This localization pattern is affected by inhibitor treatments that limit mRNA availability (such as cycloheximide or actinomycin D) or block nuclear export (leptomycin B). Coupled with its ability to bind the ribohomopolymers poly(rU) and poly(rG), these results suggest involvement of TZF9 in post-transcriptional regulation, such as mRNA processing or storage pathways, to regulate plant innate immunity.

The complete mitochondrial genome of the banana pathogen Fusarium oxysporum f. sp. cubense M5.

We report the complete mitochondrial genome of a causal agent of banana fusarium wilt isolated in Mexico. The whole set of genes encoding proteins related to respiration and ATP synthesis, rRNAs, tRNAs are enlisted. Two open reading frames of unknown function conserved in Fusarium oxysporum were also identified.