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El presente trabajo es el producto de la participación de docentes y estudiantes de pre y post-grado de la Facultad de Enfermería de la Universidad Nacional de Bogotá, en el desarrollo del programa de hipertensión arterial en el hasta hace algunos días llamado Hospital El Carmen, hoy Cami II El Carmen Sur, de Santafé de Bogotá, durante más de 14 años.

The Aedes aegypti mosquito utilizes olfaction during the search for humans to bite. The attraction to human body odor is an innate behavior for this disease-vector mosquito. Many well-studied model species have olfactory systems that conform to a particular organization that is sometimes referred to as the 'one-receptor-to-one-neuron' organization because each sensory neuron expresses only a single type of olfactory receptor that imparts the neuron's chemical selectivity. This sensory architecture has become the canon in the field. This review will focus on the recent finding that the olfactory system of Ae. aegypti has a different organization, with multiple olfactory receptors co-expressed in many of its olfactory sensory neurons. We will discuss the canonical organization and how this differs from the non-canonical organization, examine examples of non-canonical olfactory systems in other species, and discuss the possible roles of receptor co-expression in odor coding in the mosquito and other organisms., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The eLife Early-Career Advisory Group discusses eLife's new peer review and publishing model, and how the whole process of scientific communication could be improved for the benefit of early-career researchers and the entire scientific community., Competing Interests: LU, MD, FF, HE, LH, DM, RM, DM, EO, CP, FR, LS, AT, AV, LY No competing interests declared, (© 2022, Urban et al.)

An essential requirement of every laboratory procedure is to have all materials ready when they are needed, so that the experimental flow is not disrupted. This is particularly true for patch clamping; therefore, effort must be devoted in advance to produce materials such as patch pipettes. This can be a fiddly business; hence, this protocol provides step-by-step advice on how to pull and polish patch-clamp pipettes. It also includes a brief description on how to prepare homemade filling devices to deliver saline efficiently and inexpensively into the pipettes. The protocol ends with guidelines on how to change the filament of a Sutter horizontal puller, a dreaded yet necessary activity that should be learned by anyone who wishes to become an expert patch clamper., (© 2022 Cold Spring Harbor Laboratory Press.)

The brain of adult flies ( Drosophila melanogaster ) has been studied in detail from several perspectives, including the anatomical and molecular characterization of hundreds of neuronal types. However, information regarding the electrophysiological properties of most neuronal types is lacking. This protocol provides detailed information on how to dissect the brain of adult flies to produce an ex vivo preparation in which central neurons can be patch-clamped. Immobilizing fresh and tiny tissues, such as fly brains, to perform successful patch-clamp recordings is a critical step; here, we explain how this can be achieved using cyanoacrylate glue., (© 2022 Cold Spring Harbor Laboratory Press.)

Drosophila melanogaster is widely used as a model organism in all fields of biomedical research. In neuroscience, vast amounts of information have been gained using this little fly including the identification of neuronal circuits that regulate behaviors, the unraveling of their genetic underpinnings, and the molecular mechanisms involved. With plenty of genetic tools available to manipulate and infer neuronal activity, the direct measurement of electrical properties of fly neurons has lagged behind. This is due to the intricacies of performing electrical recordings in small cells such as fly central neurons. The patch-clamp technique offers the unique possibility of directly measuring the electrical properties of Drosophila neurons. This step-by-step protocol provides detailed advice for mastering this technique., (© 2022 Cold Spring Harbor Laboratory Press.)

The membrane potential of excitable cells, such as neurons and muscle cells, experiences a rich repertoire of dynamic changes mediated by an array of ligand- and voltage-gated ion channels. Central neurons, in particular, are fantastic computators of information, sensing, and integrating multiple subthreshold currents mediated by synaptic inputs and translating them into action potential patterns. Electrophysiology comprises a group of techniques that allow the direct measurement of electrical signals. There are many different electrophysiological approaches, but, because Drosophila neurons are small, the whole-cell patch-clamp technique is the only applicable method for recording electrical signals from individual central neurons. Here, we provide background on patch-clamp electrophysiology in Drosophila and introduce protocols for dissecting larval and adult brains, as well as for achieving whole-cell patch-clamp recordings of identified neuronal types. Patch clamping is a labor-intensive technique that requires a great deal of practice to become an expert; therefore, a steep learning curve should be anticipated. However, the instant gratification of neuronal spiking is an experience that we wish to share and disseminate, as many more Drosophila patch clampers are needed to study the electrical features of so many fly neuronal types unknown to date., (© 2022 Cold Spring Harbor Laboratory Press.)

An enormous amount of neuroscientific knowledge has been gained from studying the larval stage of Drosophila From an electrophysiological point of view, the larval neuromuscular junction has played an important role in this quest for knowledge, as it presents practical advantages such as accessibility and a stereotypic pattern. The physiological properties of larval central neurons have been less explored, with information regarding mainly a few identified motoneurons available to date. This protocol describes a quick and easy dissection of the brain of wandering third-instar Drosophila larvae to produce an ex vivo preparation in which central neurons can be patch-clamped. Immobilizing fresh and tiny tissues, such as larval brains, to perform successful patch-clamp recordings is a crucial step; here we explain in detail how this can be achieved using cyanoacrylate glue., (© 2022 Cold Spring Harbor Laboratory Press.)

Early career researchers (ECRs) are important stakeholders leading efforts to catalyze systemic change in research culture and practice. Here, we summarize the outputs from a virtual unconventional conference (unconference), which brought together 54 invited experts from 20 countries with extensive experience in ECR initiatives designed to improve the culture and practice of science. Together, we drafted 2 sets of recommendations for (1) ECRs directly involved in initiatives or activities to change research culture and practice; and (2) stakeholders who wish to support ECRs in these efforts. Importantly, these points apply to ECRs working to promote change on a systemic level, not only those improving aspects of their own work. In both sets of recommendations, we underline the importance of incentivizing and providing time and resources for systems-level science improvement activities, including ECRs in organizational decision-making processes, and working to dismantle structural barriers to participation for marginalized groups. We further highlight obstacles that ECRs face when working to promote reform, as well as proposed solutions and examples of current best practices. The abstract and recommendations for stakeholders are available in Dutch, German, Greek (abstract only), Italian, Japanese, Polish, Portuguese, Spanish, and Serbian., Competing Interests: The authors have declared that no competing interests exist.

Circadian rhythms have been extensively studied in Drosophila ; however, still little is known about how the electrical properties of clock neurons are specified. We have performed a behavioral genetic screen through the downregulation of candidate ion channels in the lateral ventral neurons (LNvs) and show that the hyperpolarization-activated cation current I h is important for the behaviors that the LNvs influence: temporal organization of locomotor activity, analyzed in males, and sleep, analyzed in females. Using whole-cell patch clamp electrophysiology we demonstrate that small LNvs (sLNvs) are bursting neurons, and that I h is necessary to achieve the high-frequency bursting firing pattern characteristic of both types of LNvs in females. Since firing in bursts has been associated to neuropeptide release, we hypothesized that I h would be important for LNvs communication. Indeed, herein we demonstrate that I h is fundamental for the recruitment of pigment dispersing factor (PDF) filled dense core vesicles (DCVs) to the terminals at the dorsal protocerebrum and for their timed release, and hence for the temporal coordination of circadian behaviors. SIGNIFICANCE STATEMENT Ion channels are transmembrane proteins with selective permeability to specific charged particles. The rich repertoire of parameters that may gate their opening state, such as voltage-sensitivity, modulation by second messengers and specific kinetics, make this protein family a determinant of neuronal identity. Ion channel structure is evolutionary conserved between vertebrates and invertebrates, making any discovery easily translatable. Through a screen to uncover ion channels with roles in circadian rhythms, we have identified the I h channel as an important player in a subset of clock neurons of the fruit fly. We show that lateral ventral neurons (LNvs) need I h to fire action potentials in a high-frequency bursting mode and that this is important for peptide transport and the control of behavior., (Copyright © 2021 the authors.)

Dopamine is a wake-promoting neuromodulator in mammals and fruit flies. In Drosophila melanogaster , the network of clock neurons that drives sleep/activity cycles comprises both wake-promoting and sleep-promoting cell types. The large ventrolateral neurons (l-LN v s) and small ventrolateral neurons (s-LN v s) have been identified as wake-promoting neurons within the clock neuron network. The l-LN v s are innervated by dopaminergic neurons, and earlier work proposed that dopamine signaling raises cAMP levels in the l-LN v s and thus induces excitatory electrical activity (action potential firing), which results in wakefulness and inhibits sleep. Here, we test this hypothesis by combining cAMP imaging and patch-clamp recordings in isolated brains. We find that dopamine application indeed increases cAMP levels and depolarizes the l-LN v s, but, surprisingly, it does not result in increased firing rates. Downregulation of the excitatory D 1 -like dopamine receptor (Dop1R1) in the l-LN v s and s-LN v s, but not of Dop1R2, abolished the depolarization of l-LN v s in response to dopamine. This indicates that dopamine signals via Dop1R1 to the l-LN v s. Downregulation of Dop1R1 or Dop1R2 in the l-LN v s and s-LN v s does not affect sleep in males. Unexpectedly, we find a moderate decrease of daytime sleep with downregulation of Dop1R1 and of nighttime sleep with downregulation of Dop1R2. Since the l-LN v s do not use Dop1R2 receptors and the s-LN v s also respond to dopamine, we conclude that the s-LN v s are responsible for the observed decrease in nighttime sleep. In summary, dopamine signaling in the wake-promoting LN v s is not required for daytime arousal, but likely promotes nighttime sleep via the s-LN v s. SIGNIFICANCE STATEMENT In insect and mammalian brains, sleep-promoting networks are intimately linked to the circadian clock, and the mechanisms underlying sleep and circadian timekeeping are evolutionarily ancient and highly conserved. Here we show that dopamine, one important sleep modulator in flies and mammals, plays surprisingly complex roles in the regulation of sleep by clock-containing neurons. Dopamine inhibits neurons in a central brain sleep center to promote sleep and excites wake-promoting circadian clock neurons. It is therefore predicted to promote wakefulness through both of these networks. Nevertheless, our results reveal that dopamine acting on wake-promoting clock neurons promotes sleep, revealing a previously unappreciated complexity in the dopaminergic control of sleep., (Copyright © 2020 the authors.)

The need to protect public health during the current COVID-19 pandemic has necessitated conference cancellations on an unprecedented scale. As the scientific community adapts to new working conditions, it is important to recognize that some of our actions may disproportionately affect early-career researchers and scientists from countries with limited research funding. We encourage all conference organizers, funders and institutions who are able to do so to consider how they can mitigate the unintended consequences of conference and travel cancellations and we provide seven recommendations for how this could be achieved. The proposed solutions may also offer long-term benefits for those who normally cannot attend conferences, and thus lead to a more equitable future for generations of researchers., Competing Interests: TW, YB, Cd, HE, FF, VI, DM, CP, JR, SS, SS, AT No competing interests declared, (© 2020, Weissgerber et al.)

We describe a case of Wilson's disease (WD) diagnosed at 5 years after routine biochemical test showed increased aminotransferases. Mutation analysis of the ATP7B gene revealed a 3039-bp deletion in the homozygous state spanning from the terminal part of intron 1 to nt position 368 of exon 2. This deletion results in the activation of 3 cryptic splice sites: an AG acceptor splice site in nt positions 578-579 producing a different breakpoint and removing the first 577 nts of exon 2, an acceptor and a donor splice site in nt positions 20363-4 and 20456-7, respectively, in intron 1, resulting in the activation of a 94-bp cryptic Alu exon being incorporated into the mature transcript. The resulting alternative transcript contains a TAG stop codon in the first amino acid position of the cryptic exon, likely producing a truncated, non-functional protein. This study shows that intron exonization can also occur in humans through naturally occurring gross deletions. The results suggest that the combination of DNA and RNA analyses can be used for molecular characterization of gross ATP7B deletions, thus improving genetic counseling and diagnosis of WD. Moreover these studies help to better establish new molecular mechanisms producing Wilson's disease., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Crisponi syndrome (CS) and cold-induced sweating syndrome type 1 (CISS1) share clinical characteristics, such as dysmorphic features, muscle contractions, scoliosis, and cold-induced sweating, with CS patients showing a severe clinical course in infancy involving hyperthermia associated with death in most cases in the first years of life. To date, 24 distinct CRLF1 mutations have been found either in homozygosity or in compound heterozygosity in CS/CISS1 patients, with the highest prevalence in Sardinia, Turkey, and Spain. By reporting 11 novel CRLF1 mutations, here we expand the mutational spectrum of CRLF1 in the CS/CISS1 syndrome to a total of 35 variants and present an overview of the different molecular and clinical features of all of them. To catalog all the 35 mutations, we created a CRLF1 mutations database, based on the Leiden Open (source) Variation Database (LOVD) system (https://grenada.lumc.nl/LOVD2/mendelian_genes/variants). Overall, the available functional and clinical data support the fact that both syndromes actually represent manifestations of the same autosomal-recessive disorder caused by mutations in the CRLF1 gene. Therefore, we propose to rename the two overlapping entities with the broader term of Crisponi/CISS1 syndrome., (© 2014 WILEY PERIODICALS, INC.)

Summary: Crisponi syndrome (CS) is a rare, autosomal recessive disorder, characterized by hyperthermia, extensive muscular contractions in the face after even minimal stimuli or crying, hypertonia, opisthotonus, camptodactyly, and typical facial features. Recently, it has been demonstrated that CRLF1 (cytokine receptor-like factor 1) gene mutation is associated with CS. Here we report a case of CS with a new mutation in the CRLF1 gene associated with moderate clinical phenotype.

Crisponi syndrome (CS) and cold-induced sweating syndrome type 1 (CISS1) are disorders caused by mutations in CRLF1. The two syndromes share clinical characteristics, such as dysmorphic features, muscle contractions, scoliosis and cold-induced sweating, with CS patients showing a severe clinical course in infancy involving hyperthermia, associated with death in most cases in the first years of life. To evaluate a potential genotype/phenotype correlation and whether CS and CISS1 represent two allelic diseases or manifestations at different ages of the same disorder, we carried out a detailed clinical analysis of 19 patients carrying mutations in CRLF1. We studied the functional significance of the mutations found in CRLF1, providing evidence that phenotypic severity of the two disorders mainly depends on altered kinetics of secretion of the mutated CRLF1 protein. On the basis of these findings, we believe that the two syndromes, CS and CISS1, represent manifestations of the same disorder, with different degrees of severity. We suggest renaming the two genetic entities CS and CISS1 with the broader term of Sohar-Crisponi syndrome.

Congenital portosystemic shunts (PSS) are rare vascular anomalies with different gross anatomy. Persistent patent ductus venosus (PDV) represents an uncommon cause of intrahepatic PSS. The diagnosis of this condition may not be obvious because of its wide spectrum of clinical manifestations, ranging from asymptomatic to life-threatening disease. We report the case of three boys with neuropsychological symptoms associated with mild fasting hyperammonemia. An oral protein load allowed the detection of a detoxication defect due to PSS related to PDV. This simple procedure can be worthwhile of attention in patients with mental retardation, behavior disturbances, and learning difficulties after exclusion of common causes of inherited hyperammonemia, namely, urea cycle disorders, organic acidemias, and fatty acid oxidation defects.

Crisponi syndrome is a severe autosomal recessive condition that is phenotypically characterized by abnormal, paroxysmal muscular contractions resembling neonatal tetanus, large face, broad nose, anteverted nares, camptodactyly, hyperthermia, and sudden death in most cases. We performed homozygosity mapping in five Sardinian and three Turkish families with Crisponi syndrome, using high-density single-nucleotide polymorphism arrays, and identified a critical region on chromosome 19p12-13.1. The most prominent candidate gene was CRLF1, recently found to be involved in the pathogenesis of cold-induced sweating syndrome type 1 (CISS1). CISS1 belongs to a group of conditions with overlapping phenotypes, also including cold-induced sweating syndrome type 2 and Stuve-Wiedemann syndrome. All these syndromes are caused by mutations of genes of the ciliary neurotrophic factor (CNTF)-receptor pathway. Here, we describe the identification of four different CRLF1 mutations in eight different Crisponi-affected families, including a missense mutation, a single-nucleotide insertion, and a nonsense and an insertion/deletion (indel) mutation, all segregating with the disease trait in the families. Comparison of the mutation spectra of Crisponi syndrome and CISS1 suggests that neither the type nor the location of the CRLF1 mutations points to a phenotype/genotype correlation that would account for the most severe phenotype in Crisponi syndrome. Other, still-unknown molecular factors may be responsible for the variable phenotypic expression of the CRLF1 mutations. We suggest that the syndromes can comprise a family of "CNTF-receptor-related disorders," of which Crisponi syndrome would be the newest member and allelic to CISS1.

Blepharophimosis-ptosis-epicanthus inversus syndrome (OMIM #U10100) is a rare autosomal-dominant disorder in which an eyelid malformation is associated (type I) or not (type H) with premature ovarian failure in the affected female. It is invariably characterized by 4 major features: (1) bilaterally shortened horizontal palpebral fissure (blepharophimosis); (2) severe impairment of the superior palpebral levator (ptosis); (3) a vertical skin fold arising from the lower eyelid, which inserts medially in the upper lid (epicanthus inversus) and (4) an increased inner can-thal distance with a normal outer canthal distance (telecanthus). The mutations causing this disorder are found in the FOXL2 gene, a forkhead transcription factor, located in 3q23. Although many patients with blepharophimosis-ptosis-epicanthus inversus syndrome have an affected parent, a conspicuous number of sporadic cases also have been reported. We describe here a sporadic case with a mutation in the FOXL2 gene that was well characterized both clinically and molecularly.

A translocation breakpoint 171 kb 5' of the transcription start of FOXL2 causes blepharophimosis/ptosis/epicanthus inversus syndrome (BPES) and associated premature ovarian failure. The breakpoint falls within another gene, MRPS22, that has been sequenced in 500 kb of continuous DNA. MRPS22 encodes 20 exons and a number of alternative transcripts. Three CpG islands (>91% identical) are followed by noncoding exons 4-12 and coding exons 13-20. The 3'UTR extends into the 3'UTR of COPB2. Based on the sequence, three reported translocations that cause BPES all fall within intron 6 of MRPS22. Comparisons reveal conserved segments in introns 6, 11, and 12 of human and mouse. Notably intron 11 sequence is also deleted in goat PIS syndrome (which combines craniofacial defects, female infertility, and XX sex reversal). The conserved sequences are candidates for models in which they are distant enhancers or otherwise affect higher order chromatin structure to impose long-range cis regulation of FOXL2 expression.

The specific aim of the study was to assess the safety and efficacy of recombinant human erythropoietin (rHuEpo) in reducing the need for blood transfusions in preterm infants after the 15th day of life. Between 1 October 1994 and 1 October 1995, 107 preterm infants, gestational age < or = 34 weeks, were admitted to the Neonatal Intensive Care Unit and received rHuEpo subcutaneously, 900 U/kg week-1, 3 times weekly, supplemented with iron and vitamin E. Treatment was started at 8 days of life and lasted from a minimum of 6 weeks to a maximum of 3 months. A total of 116 preterm infants of the same gestational age, admitted to the Neonatal Intensive Care Unit from 1 January 1992 to 31 December 1992, served as controls. Entry criteria were gestational age < or = 34 weeks and no major congenital malformation. There were no differences in routine care between the two groups. Hematological measurements and transfusion requirements were followed during therapy. The infants were divided into two groups according to birth weight (< 1500 g and > or = 1500 g), and for each group the number of patients who received blood transfusions and when blood transfusions occurred, before or after the 15th day of life, was recorded. There was a statistically significant difference only for transfusions carried out after the 15th day of life (p < 0.002). No adverse effects attributable to rHuEpo during the treatment were noted. The results indicate that early rHuEpo treatment, in combination with iron supplements, is effective in reducing the need for blood transfusions in preterm infants after the 15th day of life.

The Italian Multicenter Study on Very Low Birth Weight babies (IMS-VLBW) is the first collaborative investigation performed in Italy on the health status of newborns weighing less than 1500 g at birth. Eight Neonatal Intensive Care Units (NICUs) participated in the study: Cagliari, Napoli, Padova, Palermo, Roma, Sassari, Trieste, Udine. Data were analyzed in the Laboratorio di Epidemiologia e Biostatistica of the Istituto Superiore di Sanità. The objectives of the study were established in the following: a) to collect accurate descriptive data on neonatal morbidity, mortality and long term outcome of VLBW babies admitted to NICUs; b) to analyze the risk factors of unfavourable outcome (death or handicap) and to analyze, with respect to outcome, the relationships between risk factors, neonatal diseases and therapeutical procedures; c) to test the feasibility of a multicenter follow-up programme based on the use in all participating Centers of the same diagnostic criteria (the results of follow-up will be presented in a forthcoming paper). In the years 1987 and 1988, 634 newborns weighing 500-1499 g at birth were enrolled in the study. In-hospital mortality for the whole group was 33.1% (65.1% in the 500-999 g birth weight class and 19.2% in the 1000-1499 g class). Mortality was not different for inborn vs outborn babies. A high incidence of unfavourable perinatal conditions was observed in these babies, namely birth asphyxia, sub-optimal care during transport, poor clinical conditions on arrival to the NICU. Neonatal diseases, like respiratory distress syndrome and peri-intra ventricular hemorrhage were also frequent and severe. A logistic regression analysis of pre-admission risk factors of in-hospital death identified eight statistically significant variables: birth weight; gestational age; sex; antenatal steroid stimulation of lung maturity; first minute Apgar score; absence of spontaneous respiration, body temperature and pH on arrival to the NICU. Using the equation derived from the logistic regression analysis a theoretical mortality rate, predicted on the basis of the local incidence of pre-admission risk factors, was calculated for each Center. In no case the predicted mortality was statistically different from the observed one, suggesting that in our study differences in observed mortality rates from one Center to another are largely influenced by pre-admission risk factors.