•Seasonal influenza viruses typically circulate in South America from April-November.•Among those vaccinated in 2022, the odds of influenza hospitalization were 1/3 lower.•Vaccine effectiveness was ...higher in the early season than in the late season.•Health officials should encourage communities to seek influenza vaccination.
This study estimated the 2022 end-of-season influenza vaccine effectiveness (VE) against severe acute respiratory illness (SARI) hospitalization in Chile, Paraguay, and Uruguay.
We pooled surveillance data from SARI cases in 18 sentinel surveillance hospitals in Chile (n = 9), Paraguay (n = 2), and Uruguay (n = 7) from March 16-November 30, 2022. VE was estimated using a test-negative design and logistic regression models adjusted for country, age, sex, presence of ≥1 comorbidity, and week of illness onset. VE estimates were stratified by influenza virus type and subtype (when available) and influenza vaccine target population, categorized as children, individuals with comorbidities, and older adults, defined per countries’ national immunization policies.
Among the 3147 SARI cases, there were 382 (12.1%) influenza test-positive case patients; 328 (85.9%) influenza case patients were in Chile, 33 (8.6%) were in Paraguay, and 21 (5.5%) were in Uruguay. In all countries, the predominant subtype was influenza A(H3N2) (92.6% of influenza cases). Adjusted VE against any influenza-associated SARI hospitalization was 33.8% (95% confidence interval: 15.3%, 48.2%); VE against influenza A(H3N2)-associated SARI hospitalization was 30.4% (95% confidence interval: 10.1%, 46.0%). VE estimates were similar across target populations.
During the 2022 influenza season, influenza vaccination reduced the odds of hospitalization among those vaccinated by one-third. Health officials should encourage influenza vaccination in accordance with national recommendations.
Many forms of blindness result from the dysfunction or loss of retinal photoreceptors. Induced pluripotent stem cells (iPSCs) hold great potential for the modelling of these diseases or as potential ...therapeutic agents. However, to fulfill this promise, a remaining challenge is to induce human iPSC to recreate in vitro key structural and functional features of the native retina, in particular the presence of photoreceptors with outer-segment discs and light sensitivity. Here we report that hiPSC can, in a highly autonomous manner, recapitulate spatiotemporally each of the main steps of retinal development observed in vivo and form three-dimensional retinal cups that contain all major retinal cell types arranged in their proper layers. Moreover, the photoreceptors in our hiPSC-derived retinal tissue achieve advanced maturation, showing the beginning of outer-segment disc formation and photosensitivity. This success brings us one step closer to the anticipated use of hiPSC for disease modelling and open possibilities for future therapies.
Lens regeneration in adult newts is a classic example of how cells can faithfully regenerate a complete organ through the process of transdifferentiation. After lens removal, the pigment epithelial ...cells of the dorsal, but not the ventral, iris dedifferentiate and then differentiate to form a new lens. Understanding how this process is regulated might provide clues about why lens regeneration does not occur in higher vertebrates. The genes six-3 and pax-6 are known to induce ectopic lenses during embryogenesis. Here we tested these genes, as well as members of the bone morphogenetic protein (BMP) pathway that regulate establishment of the dorsal-ventral axis in embryos, for their ability to induce lens regeneration. We show that the lens can be regenerated from the ventral iris when the BMP pathway is inhibited and when the iris is transfected with six-3 and treated with retinoic acid. In intact irises, six-3 is expressed at higher levels in the ventral than in the dorsal iris. During regeneration, however, only expression in the dorsal iris is significantly increased. Such an increase is seen in ventral irises only when they are induced to transdifferentiate by six-3 and retinoic acid or by BMP inhibitors. These data suggest that lens regeneration can be achieved in noncompetent adult tissues and that this regeneration occurs through a gene regulatory mechanism that is more complex than the dorsal expression of lens regeneration-specific genes.
Retinal disease represents a growing global problem, both in terms of quality of life and economic impact, yet new therapies are not being developed at a sufficient rate to meet this mounting need. ...In this context, retinal organoids derived from human induced pluripotent stem cells hold significant promise for improving upon the current drug development process, increasing the speed and efficiency of moving potential therapeutic agents from bench to bedside. These organoid systems display the cell-cell and cell-matrix interactions, cellular heterogeneity, and physiological responses reflective of human biology and, thus, have the ability to replicate retinal disease pathology in a way that 2-dimensional cell cultures and animal models have been heretofore unable to achieve. However, organoid technology is not yet mature enough to meet the high-throughput demands of the first stages of drug screening. Hence, the augmentation of the existing drug development pipeline with retinal organoids, rather than the replacement of existing pathway components, may provide a way to harness the benefits of this improved pathological modeling. In this study, we outline the possible benefits of such a symbiosis, discuss other potential uses, and highlight barriers that remain to be overcome.
The ability to generate human retinas in vitro from pluripotent stem cells opened unprecedented opportunities for basic science and for the development of therapeutic approaches for retinal ...degenerative diseases. Retinal organoid models not only mimic the histoarchitecture and cellular composition of the native retina, but they can achieve a remarkable level of maturation that allows them to respond to light stimulation. However, studies evaluating the nature, magnitude, and properties of light-evoked responsivity from each cell type, in each retinal organoid layer, have been sparse. In this review we discuss the current understanding of retinal organoid function, the technologies used for functional assessment in human retinal organoids, and the challenges and opportunities that lie ahead.
Stem cells offer unprecedented opportunities for the development of strategies geared toward the treatment of retinal degenerative diseases. A variety of cellular sources have been investigated for ...various potential clinical applications, including tissue regeneration, disease modeling, and screening for non-cell-based therapeutic agents. As the field transitions from more than a decade of preclinical research to the first phase I/II clinical trials, we provide a concise overview of the stem cell sources most commonly used, weighing their therapeutic potential on the basis of their technical strengths/limitations, their ethical implications, and the extent of the progress achieved to date. This article serves as a framework for further in-depth analyses presented in the following chapters of this Special Issue.
Resumen: La respuesta inflamatoria, frecuentemente asociada al parto prematuro extremo, tiene un rol relevante en el pronóstico, ya que la inmadurez propia del sistema inmune en estas condiciones ...impide la apropiada modulación de estos procesos, promoviendo una inflamación persistente en el tiempo con los consiguientes daños en el corto, mediano y largo plazo. Objetivo: revisar los mecanismos inmunológicos en el prematuro extremo, los efectos en los sistemas de mayor relevancia y nuevas perspectivas terapéuticas. Summary: Inflammatory response, frequently associated with extreme preterm birth, has a relevant role in outcome, since immaturity of immune system, in such conditions, does not allow an appropriate modulation of these processes leading to sustained inflammation, to secondary damage and thus promoting short-medium- and long-term sequelae. Objective: to review immunological mechanisms involved in extreme prematurity, their effects on the most relevant systems and new therapeutical approaches.
is an intracellular bacterium and the cause of the zoonotic infection, Q fever. National surveillance data on
seroprevalence is currently not available for any South American country, making efforts ...of public health to implement strategies to mitigate infections in different at-risk groups within the population extremely challenging. In the current study, we used two commercial anti-
immunoassays to screen sera collected from a sample of the Chilean population as part of a 2016-2017 national health survey (
= 5166), nationwide and age-standardized. The seroprevalence for
for persons ≥ 15 years was estimated to be 3.0% (95% CI 2.2-4.0), a level similar to national surveys from The Netherlands (2.4%) and USA (3.1%), but lower than Australia (5.6%). A linear increase of
seropositivity was associated with an individual's age, with the peak seroprevalence 5.6% (95% CI 3.6-8.6) observed in the ≥65 years' group.
seropositivity was significantly higher in the southern macro-zone 6.0% (95% CI 3.3-10.6) compared to metropolitan region 1.8% (95% CI 0.9-3.3), the former region being home to significant livestock industries, particularly dairy farming. These data will be useful to inform targeted strategies for the prevention of Q fever in at-risk populations in Chile.
Lens regeneration: a historical perspective Vergara, M Natalia; Tsissios, George; Del Rio-Tsonis, Katia
The International journal of developmental biology,
2018, Volume:
62, Issue:
6-7-8
Journal Article
Peer reviewed
Open access
The idea of regenerating injured body parts has captivated human imagination for centuries, and the topic still remains an area of extensive scientific research. This review focuses on the process of ...lens regeneration: its history, our current knowledge, and the questions that remain unanswered. By highlighting some of the milestones that have shaped our understanding of this phenomenon and the contributions of scientists who have dedicated their lives to investigating these questions, we explore how regeneration enquiry evolved into the science it is today, and how technological advances accelerated our understanding of these remarkable processes.
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