A feedback-driven IoT microfluidic, electrophysiology, and imaging platform for brain organoid studies.

The analysis of tissue cultures, particularly brain organoids, takes a high degree of coordination, measurement, and monitoring. We have developed an automated research platform enabling independent devices to achieve collaborative objectives for feedback-driven cell culture studies. Unified by an Internet of Things (IoT) architecture, our approach enables continuous, communicative interactions among various sensing and actuation devices, achieving precisely timed control of in vitro biological experiments. The framework integrates microfluidics, electrophysiology, and imaging devices to maintain cerebral cortex organoids and monitor their neuronal activity. The organoids are cultured in custom, 3D-printed chambers attached to commercial microelectrode arrays for electrophysiology monitoring. Periodic feeding is achieved using programmable microfluidic pumps. We developed computer vision fluid volume estimations of aspirated media, achieving high accuracy, and used feedback to rectify deviations in microfluidic perfusion during media feeding/aspiration cycles. We validated the system with a 7-day study of mouse cerebral cortex organoids, comparing manual and automated protocols. The automated experimental samples maintained robust neural activity throughout the experiment, comparable with the control samples. The automated system enabled hourly electrophysiology recordings that revealed dramatic temporal changes in neuron firing rates not observed in once-a-day recordings.

Modulation of neuronal activity in cortical organoids with bioelectronic delivery of ions and neurotransmitters.

Precise modulation of brain activity is fundamental for the proper establishment and maturation of the cerebral cortex. To this end, cortical organoids are promising tools to study circuit formation and the underpinnings of neurodevelopmental disease. However, the ability to manipulate neuronal activity with high temporal resolution in brain organoids remains limited. To overcome this challenge, we introduce a bioelectronic approach to control cortical organoid activity with the selective delivery of ions and neurotransmitters. Using this approach, we sequentially increased and decreased neuronal activity in brain organoids with the bioelectronic delivery of potassium ions (K+) and γ-aminobutyric acid (GABA), respectively, while simultaneously monitoring network activity. This works highlights bioelectronic ion pumps as tools for high-resolution temporal control of brain organoid activity toward precise pharmacological studies that can improve our understanding of neuronal function.

Fabrication and Characterization of a Flexible Thin-Film-Based Array of Microelectrodes for Corneal Electrical Stimulation.

The electric stimulation (ES) of the cornea is a novel therapeutic approach to the treatment of degenerative visual diseases. Currently, ES is delivered by placing a mono-element electrode on the surface of the cornea that uniformly stimulates the eye along the electrode site. It has been reported that a certain degree of correlation exists between the location of the stimulated retinal area and the position of the electrode. Therefore, in this study, we present the development of a sectioned surface electrode for selective electric stimulation of the human cornea. The proposed device consists of 16 independent microelectrodes, a reference electrode, and 18 contact pads. The microelectrodes have a size of 200 µm × 200 µm, are arranged in a 4 × 4 matrix, and cover a total stimulation area of 16 mm2. The proposed fabrication process, based on surface micromachining technology and flexible electronics, uses only three materials: polyimide, aluminum, and titanium, which allow us to obtain a simplified, ergonomic, and reproducible fabrication process. The fabricated prototype was validated to laboratory level by electrical and electrochemical tests, showing a relatively high electrical conductivity and average impedance from 712 kΩ to 1.4 MΩ at the clinically relevant frequency range (from 11 Hz to 30 Hz). Additionally, the biocompatibility of the electrode prototype was demonstrated by performing in vivo tests and by analyzing the polyimide films using Fourier transform infrared spectroscopy (FTIR). The resulting electrode prototype is robust, mechanically flexible, and biocompatible, with a high potential to be used for selective ES of the cornea.

Internet-Connected Cortical Organoids for Project-Based Stem Cell and Neuroscience Education.

The introduction of Internet-connected technologies to the classroom has the potential to revolutionize STEM education by allowing students to perform experiments in complex models that are unattainable in traditional teaching laboratories. By connecting laboratory equipment to the cloud, we introduce students to experimentation in pluripotent stem cell (PSC)-derived cortical organoids in two different settings: using microscopy to monitor organoid growth in an introductory tissue culture course and using high-density (HD) multielectrode arrays (MEAs) to perform neuronal stimulation and recording in an advanced neuroscience mathematics course. We demonstrate that this approach develops interest in stem cell and neuroscience in the students of both courses. All together, we propose cloud technologies as an effective and scalable approach for complex project-based university training.

Internet-connected cortical organoids for project-based stem cell and neuroscience education.

The introduction of internet-connected technologies to the classroom has the potential to revolutionize STEM education by allowing students to perform experiments in complex models that are unattainable in traditional teaching laboratories. By connecting laboratory equipment to the cloud, we introduce students to experimentation in pluripotent stem cell-derived cortical organoids in two different settings: Using microscopy to monitor organoid growth in an introductory tissue culture course, and using high density multielectrode arrays to perform neuronal stimulation and recording in an advanced neuroscience mathematics course. We demonstrate that this approach develops interest in stem cell and neuroscience in the students of both courses. All together, we propose cloud technologies as an effective and scalable approach for complex project-based university training.

Modulation of neuronal activity in cortical organoids with bioelectronic delivery of ions and neurotransmitters.

Precise modulation of brain activity is fundamental for the proper establishment and maturation of the cerebral cortex. To this end, cortical organoids are promising tools to study circuit formation and the underpinnings of neurodevelopmental disease. However, the ability to manipulate neuronal activity with high temporal resolution in brain organoids remains limited. To overcome this challenge, we introduce a bioelectronic approach to control cortical organoid activity with the selective delivery of ions and neurotransmitters. Using this approach, we sequentially increased and decreased neuronal activity in brain organoids with the bioelectronic delivery of potassium ions (K+) and γ-aminobutyric acid (GABA), respectively, while simultaneously monitoring network activity. This works highlights bioelectronic ion pumps as tools for high-resolution temporal control of brain organoid activity toward precise pharmacological studies that can improve our understanding of neuronal function.

Open-loop lab-on-a-chip technology enables remote computer science training in Latinx life sciences students.

Despite many interventions, science education remains highly inequitable throughout the world. Among all life sciences fields, Bioinformatics and Computational Biology suffer from the strongest underrepresentation of racial and gender minorities. Internet-enabled project-based learning (PBL) has the potential to reach underserved communities and increase the diversity of the scientific workforce. Here, we demonstrate the use of lab-on-a-chip (LoC) technologies to train Latinx life science undergraduate students in concepts of computer programming by taking advantage of open-loop cloud-integrated LoCs. We developed a context-aware curriculum to train students at over 8,000 km from the experimental site. We showed that this approach was sufficient to develop programming skills and increase the interest of students in continuing careers in Bioinformatics. Altogether, we conclude that LoC-based Internet-enabled PBL can become a powerful tool to train Latinx students and increase the diversity in STEM.

Identification of peptide epitopes of the gp120 protein of HIV-1 capable of inducing cellular and humoral immunity.

The Human Immunodeficiency Virus (HIV-1) causes Acquired Immunodeficiency Syndrome (AIDS) and a high percentage of deaths. Therefore, it is necessary to design vaccines against HIV-1 for the prevention of AIDS. Bioinformatic tools and theoretical algorisms allow us to understand the structural proteins of viruses to develop vaccines based on immunogenic peptides (epitopes). In this work, we identified the epitopes: P1, P2, P10, P27 and P30 from the gp120 protein of HIV-1. These peptides were administered intranasally alone or with cholera toxin (CT) to BALB/c mice. The population of CD4+, CD8+ T lymphocytes and B cells (CD19/CD138+, IgA+ and IgG+) from nasal-associated lymphoid tissue, nasal passages, cervical and inguinal nodes was determined by flow cytometry. In addition, anti-peptides IgG and IgA from serum, nasal and vaginal washings were measured by ELISA. The results show that peptides administered by i.n. can modulate the immune response of T and B lymphocyte populations, as well as IgA and IgG antibodies secretion in the different sites analyzed. In conclusion, bioinformatics tools help us to select peptides with physicochemical properties that allow the induction of the humoral and cellular responses that depend on the peptide sequence.

Patient-related effects of primary nursing : Protocol of a pilot randomized controlled trial.

BACKGROUND: Since January 2022, a primary nursing system called process-responsible nursing (PP) has substituted the standard room care system in an intensive care unit (ICU) at our institution. The process of the development and implementation of PP is already being evaluated in a separate study as an actual analysis prior to implementation, as well as after 6 and 12 months. AIM: This pilot randomized controlled trial (RCT) aims to test the feasibility of an RCT. For this purpose, the duration of delirium, among other things, will be compared in the project ICU with the results of standard care in another ICU at the university hospital. As secondary aims, the incidence of delirium, anxiety, the satisfaction of relatives, and the effects of PP on nurses will be assessed. METHODS: It is planned to recruit about 400-500 patients over a period of one year. They will be allocated to PP or standard care. Delirium will be assessed using the Confusion Assessment Method for Intensive Care Units by specifically trained nurses three times a day. Anxiety in patients, the satisfaction of relatives, and the effects of PP on nurses will be evaluated using the numeric rating scale, a standardized questionnaire, and a focus group interview, respectively. EXPECTED RESULTS: The primary hypothesis is that compared to usual care PP reduces the duration of delirium by at least 8 h. Additional hypotheses are that PP reduces anxiety in patients and increases the satisfaction of relatives.

From rivers to ocean basins: The role of ocean barriers and philopatry in the genetic structuring of a cosmopolitan coastal predator.

The Bull Shark (Carcharhinus leucas) faces varying levels of exploitation around the world due to its coastal distribution. Information regarding population connectivity is crucial to evaluate its conservation status and local fishing impacts. In this study, we sampled 922 putative Bull Sharks from 19 locations in the first global assessment of population structure of this cosmopolitan species. Using a recently developed DNA-capture approach (DArTcap), samples were genotyped for 3400 nuclear markers. Additionally, full mitochondrial genomes of 384 Indo-Pacific samples were sequenced. Reproductive isolation was found between and across ocean basins (eastern Pacific, western Atlantic, eastern Atlantic, Indo-West Pacific) with distinct island populations in Japan and Fiji. Bull Sharks appear to maintain gene flow using shallow coastal waters as dispersal corridors, whereas large oceanic distances and historical land-bridges act as barriers. Females tend to return to the same area for reproduction, making them more susceptible to local threats and an important focus for management actions. Given these behaviors, the exploitation of Bull Sharks from insular populations, such as Japan and Fiji, may instigate local decline that cannot readily be replenished by immigration, which can in turn affect ecosystem dynamics and functions. These data also supported the development of a genetic panel to ascertain the population of origin, which will be useful in monitoring the trade of fisheries products and assessing population-level impacts of this harvest.

A new parasitic copepod species of Tautochondria (Siphonostomatoida: Hyponeoidae), found in the narrowmouthed catshark Schroederichthys bivius from the Strait of Magellan.

Hyponeoidae is a copepod family that is rare around the world, with only three species described until now. Recently, a hyponeoid copepod was found in the narrowmouthed catshark, Schroederichthys bivius, from Chile, which has not been formally described. The objective of this study is to describe morphologically a new species of Hyponeoidae, from samples of the Strait of Magellan, Southern Chile. Also, a genetic analysis, based on the COI gene, was used to determine the relatedness of the new hyponeoid species to other copepods from Siphonostomatoida, which were available in the GenBank platform. The new species belongs to the genus Tautochondria and is here described as T. magellanica n. sp. This species differs from T. dolichoura mainly in the presence of long process at each side of the buccal cone, the absence of lobes on the head and short processes on the genital complex. According to the genetic sequences, T. magellanica n. sp. was not closely related to any other species. Therefore, this result confirms that Hyponeoidae is a separate family. However, the relatedness to other genera in Siphonostomatoida is still unknown.

Population structure and genetic connectivity of the scalloped hammerhead shark (Sphyrna lewini) across nursery grounds from the Eastern Tropical Pacific: Implications for management and conservation.

Defining demographically independent units and understanding patterns of gene flow between them is essential for managing and conserving exploited populations. The critically endangered scalloped hammerhead shark, Sphyrna lewini, is a coastal semi-oceanic species found worldwide in tropical and subtropical waters. Pregnant females give birth in shallow coastal estuarine habitats that serve as nursery grounds for neonates and small juveniles, whereas adults move offshore and become highly migratory. We evaluated the population structure and connectivity of S. lewini in coastal areas and one oceanic island (Cocos Island) across the Eastern Tropical Pacific (ETP) using both sequences of the mitochondrial DNA control region (mtCR) and 9 nuclear-encoded microsatellite loci. The mtCR defined two genetically discrete groups: one in the Mexican Pacific and another one in the central-southern Eastern Tropical Pacific (Guatemala, Costa Rica, Panama, and Colombia). Overall, the mtCR data showed low levels of haplotype diversity ranging from 0.000 to 0.608, while nucleotide diversity ranged from 0.000 to 0.0015. More fine-grade population structure was detected using microsatellite loci where Guatemala, Costa Rica, and Panama differed significantly. Relatedness analysis revealed that individuals within nursery areas were more closely related than expected by chance, suggesting that S. lewini may exhibit reproductive philopatric behaviour within the ETP. Findings of at least two different management units, and evidence of philopatric behaviour call for intensive conservation actions for this highly threatened species in the ETP.

A priority nursery area for the conservation of the scalloped hammerhead shark Sphyrna lewini in Mexico.

This study describes the genetic diversity and level of genetic differentiation of the scalloped hammerhead shark Sphyrna lewini from eight putative nursery areas in the Mexican Pacific Ocean, using the mtDNA control region. Genetic analyses revealed a particular spatial divergence between La Reforma and all the remaining sites, with five exclusive haplotypes and the highest genetic diversity. This pattern may be interpreted as the signature of regional female philopatry, relatively to a particular female-mediated gene flow for La Reforma, which shows a strong subdivision in the Gulf of California.

Novel Sandwich-Structured Hollow Fiber Membrane for High-Efficiency Membrane Distillation and Scale-Up for Pilot Validation.

Hollow fiber membranes were produced from a commercial polyvinylidene fluoride (PVDF) polymer, Kynar HSV 900, with a unique sandwich structure consisting of two sponge-like layers connected to the outer and inner skin layers while the middle layer comprises macrovoids. The sponge-like layer allows the membrane to have good mechanical strength even at low skin thickness and favors water vapor transportation during vacuum membrane distillation (VMD). The middle layer with macrovoids helps to significantly reduce the trans-membrane resistance during water vapor transportation from the feed side to the permeate side. Together, these novel structural characteristics are expected to render the PVDF hollow fiber membranes more efficient in terms of vapor flux as well as mechanical integrity. Using the chemistry and process conditions adopted from previous work, we were able to scale up the membrane fabrication from a laboratory scale of 1.5 kg to a manufacturing scale of 50 kg with consistent membrane performance. The produced PVDF membrane, with a liquid entry pressure (LEPw) of >3 bar and a pure water flux of >30 L/m2·hr (LMH) under VMD conditions at 70−80 °C, is perfectly suitable for next-generation high-efficiency membranes for desalination and industrial wastewater applications. The technology translation efforts, including membrane and module scale-up as well as the preliminary pilot-scale validation study, are discussed in detail in this paper.

Phylogenetic relationships, origin and historical biogeography of the genus Sprattus (Clupeiformes: Clupeidae).

The genus Sprattus comprises five species of marine pelagic fishes distributed worldwide in antitropical, temperate waters. Their distribution suggests an ancient origin during a cold period of the earth's history. In this study, we evaluated this hypothesis and corroborated the non-monophyly of the genus Sprattus, using a phylogenetic approach based on DNA sequences of five mitochondrial genome regions. Sprattus sprattus is more closely related to members of the genus Clupea than to other Sprattus species. We also investigated the historical biogeography of the genus, with the phylogenetic tree showing two well-supported clades corresponding to the species distribution in each hemisphere. Time-calibrated phylogenetic analyses showed that an ancient divergence between Northern and Southern Hemispheres occurred at 55.8 MYBP, followed by a diversification in the Oligocene epoch in the Northern Hemisphere clade (33.8 MYBP) and a more recent diversification in the Southern Hemisphere clade (34.2 MYBP). Historical biogeography analyses indicated that the most recent common ancestor (MRCA) likely inhabited the Atlantic Ocean in the Southern Hemisphere. These results suggest that the ancestral population of the MRCA diverged in two populations, one was dispersed to the Northern Hemisphere and the other across the Southern Hemisphere. Given that the Eocene was the warmest epoch since the Paleogene, the ancestral populations would have crossed the tropics through deeper cooler waters, as proposed by the isothermal submergence hypothesis. The non-monophyly confirmed for the genus Sprattus indicates that its systematics should be re-evaluated.

The impact of COVID-19 on Venezuelan migrants' access to health: A qualitative study in Colombian and Peruvian cities.

This research seeks to understand how COVID-19 has affected access to healthcare among migrants in Latin American cities. Using ethnographic research methods, we engaged with Venezuelans living in conditions of informality in four Colombian cities-Barranquilla, Cucuta, Riohacha, and Soacha-and three Peruvian cities-Lima, Trujillo, and Tumbes. We conducted 130 interviews of both Venezuelan migrants and state and non-governmental actors within the healthcare ecosystems of these cities. We found that forced migrants from Venezuela in both Colombia and Peru face common obstacles along their access trajectories to healthcare, which we summarize as legal, financial, and relating to discrimination and information asymmetry. By limiting effective access to care during the pandemic, these obstacles have also affected migrants' ability to cover the costs of basic needs, particularly food and housing. Our study also found a prevalent reliance on alternative forms of care, such as telemedicine, easy-to-access pharmacies, and extralegal care networks. We conclude that COVID-19 has exacerbated preexisting conditions of informality and health inequities affecting Venezuelan migrants in Colombia and Peru.

[Defensive medicine in hospital emergency services.] / Medicina defensiva en los Servicios de Urgencias Hospitalarias.

OBJECTIVE: Hospital emergency services have specific care characteristics that make them more vulnerable to the risk of legal claims. The fact of suffering a legal claim for professional practice is a very traumatic event. The objective of this study was to find out the opinion of the professionals of the hospital emergency services in Spain on the importance of practices associated with defensive medicine. METHODS: Survey of 1,449 professionals from public and private hospital emergency services throughout the national territory was made, in the period between March 13th and April 3rd, 2017. A univariate analysis was performed to identify variables in relation to the practice of defensive medicine, and the determination of the groups of greater association (chi2 test) to evaluate these variables. RESULTS: 96.1% expressed the need to strengthen their medical-legal training. 91.3% of the cases felt more legal pressure and 88.7% declared that they act conditioned by the threat of judicial claim. Regarding patient treatments, 89.8% stated that they perform diagnostic tests that may not be necessary and 63% of professionals stated that they extend the stay of patients in the emergency department. As for the healthcare organization, 88% declared that they do not feel protected by the structure and 79.1% do not felt support from the center's management. CONCLUSIONS: Practices associated with defensive medicine are frequent in our country, with a high proportion of criminal proceedings, and the two main causes are dispensable diagnostic tests and unnecessary prolongation of length of stay.

OBJETIVO: Los Servicios de Urgencias Hospitalarias presentan características asistenciales específicas que los hacen más vulnerables al riesgo de reclamaciones legales. El hecho de sufrir una reclamación judicial por la praxis profesional es un evento muy traumático. El objetivo de este estudio fue conocer la opinión de los profesionales de los Servicios de Urgencias Hospitalarias en España sobre la importancia de las prácticas asociadas a la medicina defensiva. METODOS: Se realizó un estudio mediante encuesta a 1.449 profesionales de Servicios de Urgencias Hospitalarias públicas y privadas de todo el territorio nacional, en el periodo comprendido entre el 13 de marzo y el 3 de abril de 2017. Se realizó un análisis univariante para la identificación de variables en relación con la práctica de la medicina defensiva, así como la determinación de los grupos de mayor asociación (test χ2) para evaluar estas variables. RESULTADOS: Un 96,1% expresaron la necesidad de fortalecer su formación médico-legal. Un 91,3% de los casos sintió mayor presión legal y un 88,7% declaró actuar condicionado por la amenaza de reclamación judicial. En lo referente a los tratamientos a los pacientes, un 89,8% afirmó realizar pruebas diagnósticas que podrían no ser necesarias y un 63% de los profesionales declaró alargar la estancia de los pacientes en las Urgencias. En cuanto a la organización sanitaria, un 88% manifestó no sentirse protegido por la estructuray un 79,1% no sintió el respaldo de la dirección del centro. CONCLUSIONES: Las prácticas asociadas a la medicina defensiva son frecuentes en nuestro país, con una alta proporción de procedimientos penales, y las dos causas principales son las pruebas diagnósticas prescindibles y la prolongación innecesaria de los tiempos de estancia.

Neumonía por Pneumocystis Jirovecii en paciente adolescente inmunosuprimido no VIH positivo: Un reporte de caso / Pneumocystis Jirovecii pneumonia in a non-HIV immunosuppressed adolescent patient: A case report

Resumen La neumonía en el paciente inmunocomprometido es un reto diagnóstico al cual el clínico se enfrenta cada vez con más frecuencia , al momento de hablar de infiltrados en vidrio esmerilado es menester tener siempre en cuenta la posibilidad de neumonía por Pneumocystis Jirovecii, que por mucho tiempo se pensó como una enfermedad propia del huésped inmunosuprimido con VIH, a través del tiempo se ha manifestado en pacientes con trasplantes de órgano sólido y de precursores hematopoyéticos, asociado a autoinmunidad, al uso crónico de corticoesteroides y más recientemente al uso de terapia biológicas. La descripción de esta enfermedad y sus métodos diagnósticos en huéspedes inmunosuprimidos no VIH no es del todo claro, sabemos que el tratamiento de elección en estos casos es el trimetropin-sulfametoxazol (TMP-SMX) el cual no cuenta con evidencia de alta calidad al momento de plantear una dosis ni un tiempo de duración establecidos. Presentamos el caso de un paciente con diagnóstico de glomerulonefritis por enfermedad de cambios mínimos corticodependiente y quien desarrolló neumonía por Pneumocystis Jirovecii confirmada por histopatología quien recibió tratamiento y tuvo un desenlace positivo.

Abstract The pneumonia in the immunocompromised patient is a diagnostic challenge that the clinician faces more and more frequently, every time we talk about ground glass infiltrates it is necessary to always take into account the possibility of pneumonia due to Neumocystis Jirovecii, which for a long time was thought as a disease of the immunosuppressed host with HIV, but that across the time it has manifested itself in patients with solid organ transplants and hematopoietic precursors, associated with autoimmunity, the chronic use of corticosteroids and more recently the use of biological therapy. The description of this disease and the diagnostic methods in non-HIV immunosuppressed hosts is not entirely clear, we know that the treatment of choice in these cases is trimethropin-sulfamethoxazole (TMP-SMX), which does not have high-quality evidence at the time of a dose or a time of established duration. We present the case of a patient diagnosed with glomerulonephritis due to corticodependent minimal change disease and who suffers from pneumocystis Jirovecii pneumonia confirmed by histopathology, which received treatment and had a positive outcome