Browsing by Autor "Jorge Soliz"

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Altered thermal and metabolic control in newborn rats at high altitude
(Wiley, 2008) Vincent Joseph; Jorge Soliz; Max Gassmann; Marcelino Gonzales Isidro; Enrique Vargas; Rudy Soria
In acute hypoxia, newborn reduce oxygen consumption (VO2) and rectal temperature (Tr), but it remains unclear if these responses are maintained in chronic hypoxia. We used rats living at high altitude (3600 m, La Paz Bolivia) at postnatal days 7–8 (P7, n=5, body weight 13±1 g) and 15–16 (P15, n=6, 21±1 g). Tr and VO2 were measured in 21%O2 (room air), 35%O2 (sea level PO2), and 10%O2 (hypoxia), during 20 minutes each. Ambient temperature (Ta) was 34°C at P7 and 30°C at P15. Tr‐Ta was used as an index of thermoregulatory control. At P7, Tr‐Ta was −0.1±0.2°C, suggesting that thermoregulatory control is not established. In 35%O2, Tr was 34.8±0.2°C, and 32.0±0.6°C in 10%O2. At P15, Tr‐Ta was 5.2±0.2°C in room air, Tr did not increased in 35%O2, and was 31.8±0.4°C in 10%O2. VO2 was high (P7=8.6±0.8; P15=9.4±0.4 ml/min/100g) compared to sea level rats (5 ml/min/100g in 20g P10 rats). In P7 and P15 rats, VO2 increased in 35%O2 and dropped in 10%O2. Our results suggest that chronic hypoxia delays the establishment of thermoregulation and increases metabolic rate in newborn rats. The drop of Tr and VO2 in 10%O2 were however well maintained. Founded by NSERC
Altitude-specific neurocritical care: A case study in the management of traumatic brain injury
(Elsevier BV, 2025) Fausto Maldonado-Coronel; Catty Castillo-Caicedo; Antonio Viruez‐Soto; Roger Huanca-Payehuanca; Amílcar Tinoco-Solórzano; Daniel Molano-Franco; Christian Arias‐Reyes; Jorge Soliz
This case illustrates a unique challenge in neurocritical care at high altitude, where sea-level ventilation protocols can be detrimental. It adds novel clinical evidence by showing the pathophysiological consequences and therapeutic reversal of hypercapnia-induced cerebral hyperemia in a high-altitude native with traumatic brain injury (TBI). A 25-year-old man, lifelong resident at 3600 m above sea level (m.a.s.l.), presented with moderate-to-severe TBI following a motor vehicle accident. He exhibited cerebral edema and hemorrhagic contusions on CT, with transcranial Doppler indicating cerebral hyperemia. Initial ventilation based on sea-level PaCO₂ norms led to iatrogenic hypercapnia and cerebral hyperemia. Upon adjusting the ventilatory targets to an altitude-appropriate PaCO₂ range (26–28 mmHg), cerebral blood flow normalized, as confirmed by Doppler. The patient rapidly recovered and was discharged neurologically intact. In high-altitude settings, standard ventilation protocols may provoke secondary cerebral complications. This case highlights the critical importance of individualized, altitude-specific neurocritical strategies, with transcranial Doppler serving as a valuable bedside guide to optimize outcomes in altitude-acclimatized TBI patients. • Sealevel TBI ventilation may cause hypercapnia and cerebral hyperemia in altitud-acclimatized patients. • Setting PaCO 2 to 26-28 mmHg restored cerebral perfusion and improved neurological recovery at altitude. • Highlights the need for altitude-specific neurocritical care to improve TBI outcomes in high-altitude settings.
Bolivian CanSat Contest: Promoting Space Science and Technology
(Springer International Publishing, 2023) Jorge Soliz; Rosalyn Puma-Guzman; César Andrés Cabrera Cesar
Complex II‐linked mitochondrial respiration is upregulated during postnatal development in high‐altitude grown mice
(Wiley, 2022) Christian Arias‐Reyes; Fernanda Aliaga‐Raduán; Oscar M. Rollano‐Peñaloza; Pablo Iturri; Jorge Soliz; Vincent Joseph
Recently, we have shown that chronic normobaric hypoxia (12% O 2 – 21 days) triggers mitochondrial and cell‐ metabolic plasticity in the retrosplenial cortex of male adult FVB mice but not in SD rats. In these animals we reported a transient upregulation of anaerobic metabolic pathways (glycolysis + lactate metabolism) followed by an attenuation in the mitochondrial respiration. These results pointed to an optimized use of oxygen at cellular level in an area of the brain responsible of processing visual information and spatial memory. Features of great importance in the biological fitness. In the current work we investigate how the residence in high altitude (La Paz – Bolivia, 3,600 m) affects the developmental profile of the mitochondrial respiratory efficiency in the retrosplenial cortex of mice and rats. We hypothesize that the mitochondrial plasticity observed in adult mice will have a process of maturation during postnatal development. This response shall be absent in rats. To do so, we measured the mitochondrial oxygen consumption rate (OCR) in saponin‐permeabilized brain samples from FVB mice and SD rats born and grown in La Paz. The animals were sacrificed at postnatal ages p7, p14, p21, and adulthood (P90), and the OCR linked to the use of NADH (N pathway), FADH 2 (S pathway), or both (NS pathway) was quantified by means of high‐resolution respirometry (OROBOROS). Our results show a pattern of maturation (increase) of the mitochondrial respiration in the retrosplenial cortex along with the postnatal development (21 days+) of mice and rats. However, an upregulation of the participation of the S pathway (complex II‐linked) in the mitochondrial respiration was observed during the first three weeks of age only in mice. This observation supports previous works suggesting a key role of the complex II and succinate (substrate of complex II) in the successful cellular and mitochondrial acclimatization to hypoxia. These findings contribute to further establish FVB mice and SD rats as a model to study divergent acclimatization to hypoxia.
Consumo de Alcohol durante el Embarazo: Múltiples Efectos Negativos en el Feto
(2009) Jorge Soliz; Orlando Vladimir Vidal Lia; José Marcos Fuentes Moya; Edgar Torres López
The effects of prenatal exposure to alcohol can be identified virtually the entire body, producing among other things: serious neurological abnormalities and growth, cognitive and academic deficits, psychological disorders, behavioral problems and difficulties for independent living, in addition to increasing the risk of miscarriage, premature birth and stillbirth. The term fetal alcohol spectrum disorder is assigned to a wide range of clinical presentations in the fetus are caused by alcohol consumption during pregnancy. Fetal alcohol syndrome is the most serious of these presentations, and a condition that is both mentally and physically disabled for life because even though the research on treatments currently no cure. Finally it is important to know that all the defects caused by prenatal exposure to alcohol is totally preventable.
Coping with hypoxemia: Could erythropoietin (EPO) be an adjuvant treatment of COVID-19?
(Elsevier BV, 2020) Jorge Soliz; Edith M. Schneider Gasser; Christian Arias‐Reyes; Fernanda Aliaga‐Raduán; Liliana Poma-Machicao; Gustavo Zubieta‐Calleja; Werner I. Furuya; Pedro Trevizan‐Baú; Rishi R. Dhingra; Mathias Dutschmann
COVID-19: Multiple Diseases Simulating Extreme High-Altitude Exposure? Oxygen Transport Physiology and Scarce Need of Ventilators; Andean Condor&rsquo;s-Eye-View
(2020) Gustavo Zubieta‐Calleja; Natalia Zubieta-DeUrioste; Thuppil Venkatesh; Kusal Das; Jorge Soliz
The critical hypoxia in COVID-19 patients during this pandemic, has taken away many lives all around the globe. The mechanism has been poorly understood and initially, word got around that it was a SARS (Severe Acute Respiratory Syndrome) pneumonia. The atypical images in lung computerized axial tomography (CAT) scans were alarming. This immediately alerted everyone including poor countries to purchase lacking sophisticated ventilator equipment. However, in some countries, even 88% of the patients on ventilators lost their lives. New observations and pathological findings are gradually clarifying the disease. What seems evident is that it is not only one disease but several, with different responses in different countries and different altitudes. The critical hypoxia and &laquo;gasping&raquo; present in some patients are not totally understood. It was mentioned that it could be like a High-Altitude Pulmonary Edema (HAPE). Hereby, as high-altitude medicine and hypoxia physiology specialists, we compare the pathophysiology with that of high-altitude exposure in order to understand the mechanisms involved. Some differences in lung radiological images along with transmission and viral attack mechanisms are discussed. The oxygen transport triad used at high-altitude can be applied on this pathology in order to propose even the use of erythropoietin (EPO) early in the treatment. The immune system is the most important long-term survival tool, so we suggest a short-term strategy: the use of special Earth open-circuit astronaut-resembling suits with effective outside air filtering re-breathing mechanisms in order to return to work and daily activities, without contamination risk. Thereby, the curve can be flattened without quarantine and the economy could recover.
Design, Manufacture and Implementation of an Educational Satellite for Training in Space Communications
(2024) Jorge Soliz; I.S. Fernandez; Andersson Zurita Romero; Noelia Ayllon; Massimo La Rosa
In this project, it was possible to design, manufacture and implement successfully an educational picosatellite, marking a significant advancement in space science initiatives. The satellite features a robust communication subsystem utilizing the CC1101 module, enabling reliable data transmission over a maximum range of 1.1 km. Extensive testing confirmed the satellite’s capability to transmit environmental data with a slight margin of error compared to a meteorological station, demonstrating consistent trends in temperature and humidity readings. This initiative not only provides hands-on experience in satellite design and operation but also enhances the educational framework for university students, fostering interdisciplinary collaboration and practical engineering skills in space technology.
Development of a picosatellite for academic purposes for emerging countries
(2025) Jorge Soliz; Alejandro Jaimes; Coral Ovando; Mishel Cuiza
In Bolivia, like in most Latin American countries space projects are increasing, and this phenomenon leads to the need to train new professionals in space issues. For this reason, universities and academic centres require specialised equipment in this area. Unfortunately, this equipment has high costs (equipment such as CubeSat kit, educational satellites, satellite kit, etc.). Due to this, the design and construction of an educational and low-cost picosatellite kit with its respective signal reception equipment were necessary. The kit consists of an educational picosatellite, with a ground station, that is intended to become the perfect tool for practical training in space engineering at different levels. Potential users range from primary schools, where STEM skills development is pursued, to university engineering courses and, even, engineering companies. Additionally, this real satellite simulator offers a wide variety of educational activities without compromising cost.
Developmental expression patterns of erythropoietin and its receptor in mouse brainstem respiratory regions
(Elsevier BV, 2019) Edith M. Schneider Gasser; Elizabeth Elliot‐Portal; Christian Arias‐Reyes; Karen Losantos-Ramos; Kasifa Khalid; Omolara O. Ogunshola; Jorge Soliz
Divergent Mitochondrial Antioxidant Activities and Lung Alveolar Architecture in the Lungs of Rats and Mice at High Altitude
(Frontiers Media, 2018) Alexandra Jochmans‐Lemoine; Susana Revollo; Gabriella Villalpando; I. Valverde; Marcelino Gonzales; Sofien Laouafa; Jorge Soliz; Vincent Joseph
Compared with mice, adult rats living at 3,600 m above sea level (SL-La Paz, Bolivia) have high hematocrit, signs of pulmonary hypertension, and low lung volume with reduced alveolar surface area. This phenotype is associated with chronic mountain sickness in humans living at high altitude (HA). We tested the hypothesis that this phenotype is associated with impaired gas exchange and oxidative stress in the lungs. We used rats and mice (3 months old) living at HA (La Paz) and SL (Quebec City, Canada) to measure arterial oxygen saturation under graded levels of hypoxia (by pulse oximetry), the alveolar surface area in lung slices and the activity of pro- (NADPH and xanthine oxidases-NOX and XO) and anti- (superoxide dismutase, and glutathione peroxidase-SOD and GPx) oxidant enzymes in cytosolic and mitochondrial lung protein extracts. HA rats have a lower arterial oxygen saturation and reduced alveolar surface area compared to HA mice and SL rats. Enzymatic activities (NOX, XO, SOD, and GPx) in the cytosol were similar between HA and SL animals, but SOD and GPx activities in the mitochondria were 2-3 times higher in HA vs. SL rats, and only marginally higher in HA mice vs. SL mice. Furthermore, the maximum activity of cytochrome oxidase-c (COX) measured in mitochondrial lung extracts was also 2 times higher in HA rats compared with SL rats, while there was only a small increase in HA mice vs. SL mice. Interestingly, compared with SL controls, alterations in lung morphology are not observed for young rats at HA (15 days after birth), and enzymatic activities are only slightly altered. These results suggest that rats living at HA have a gradual reduction of their alveolar surface area beyond the postnatal period. We can speculate that the elevation of SOD, GPx, and COX activities in the lung mitochondria are not sufficient to compensate for oxidative stress, leading to damage of the lung tissue in rats.
Does the pathogenesis of SARS-CoV-2 virus decrease at high-altitude?
(Elsevier BV, 2020) Christian Arias‐Reyes; Natalia Zubieta-DeUrioste; Liliana Poma-Machicao; Fernanda Aliaga‐Raduán; Favio Carvajal-Rodriguez; Mathias Dutschmann; Edith M. Schneider Gasser; Gustavo Zubieta‐Calleja; Jorge Soliz
Dopaminergic metabolism in carotid bodies and high-altitude acclimatization in female rats
(American Physiological Society, 2002) Vincent Joseph; Jorge Soliz; Ruddy Soria; Jacqueline Pequignot; R. Favier; Hilde Spielvogel; Jean Marc Pequignot
We tested the hypothesis that ovarian steroids stimulate breathing through a dopaminergic mechanism in the carotid bodies. In ovariectomized female rats raised at sea level, domperidone, a peripheral D2-receptor antagonist, increased ventilation in normoxia (minute ventilation = +55%) and acute hypoxia (+32%). This effect disappeared after 10 daily injections of ovarian steroids (progesterone + estradiol). At high altitude (3,600 m, Bolivian Institute for High-Altitude Biology-IBBA, La Paz, Bolivia), neutered females had higher carotid body tyrosine hydroxylase activity (the rate-limiting enzyme for catecholamine synthesis: +129%) and dopamine utilization (+150%), lower minute ventilation (-30%) and hypoxic ventilatory response (-57%), and higher hematocrit (+18%) and Hb concentration (+21%) than intact female rats. Consistent signs of arterial pulmonary hypertension (right ventricular hypertrophy) also appeared in ovariectomized females. None of these parameters was affected by gonadectomy in males. Our results show that ovarian steroids stimulate breathing by lowering a peripheral dopaminergic inhibitory drive. This process may partially explain the deacclimatization of postmenopausal women at high altitude.
Efficient breathing at neonatal ages: A sex and Epo-dependent issue
(Elsevier BV, 2016) Pablo Iturri; Aïda Bairam; Jorge Soliz
Elevating STEM Education: A Ground Station's Role in Encouraging Aerospace Science Learning
(2024) Jorge Soliz; Noelia Ayllon
Aerospace science in Bolivia faces educational chal-lenges due to economic constraints and a shortage of professionals. The Private Bolivian University has responded by establishing a specialized Ground Station (GS) for tracking and transmitting signals, with a strong emphasis on education. This GS serves as a pivotal educational hub, offering talks, workshops, and tours to both school and university students, actively promoting knowledge dissemination. Initiatives include interactive workshops and guided tours, providing students with hands-on experiences to profoundly expand their educational horizons. The GS emerges as a transformative educational resource, inspiring and actively engaging younger generations in space-related disciplines. Through a dedicated collaboration with schools, the university seeks to not only enhance educational experiences but also passionately train future professionals in the dynamic field of space science. Coordinated activities, led by GS staff, expose school students early on to exciting STEM (Science, Technology, Engineering, and Mathematics) careers, fostering the development of local talent.
Enhanced erythropoietin expression in the brainstem of newborn rats at high altitude
(Elsevier BV, 2011) Tommy Seaborn; Marcelino Gonzales; Gabriela Villalpando; Beat Grenacher; Ruddy Soria; Jorge Soliz
Erythropoietin and caffeine exert similar protective impact against neonatal intermittent hypoxia: Apnea of prematurity and sex dimorphism
(Elsevier BV, 2019) Sofien Laouafa; Pablo Iturri; Christian Arias‐Reyes; François Marcouiller; Marcelino Gonzales; Vincent Joseph; Aïda Bairam; Jorge Soliz
Estudio de Rodilla Flotante en pacientes del Hospital Clinico Viedma
(2011) Jorge Soliz; Omar Marcelo Vargas Fuentes; Omar Manuel Mustafá Millán
Se denomina “Rodilla Flotante” a la combinación de fractura de fémur y tibia ipsilaterales. La incidencia exacta se desconoce, pero tiene un abordaje terapéutico complejo, una alta tasa de complicaciones y una elevada mortalidad.El presente estudio busca determinar los aspectos relacionados con esta patología en nuestro medio y analizarlos de una manera integral, realizándose para esto un estudio descriptivo y longitudinal retrospectivo abarcando 18 meses (de julio 2008 a diciembre 2009) que incluye a 17 pacientes con diagnóstico de “Rodilla Flotante” ingresados en el Servicio de Ortopedia y Traumatología del Hospital Clínico Viedma. Los resultados mostraronque esta lesión equivale al 1,9 % de los casos atendidos por este servicio. Siendo el 82,35% hombres. La edad promedio fue de 34 años. El mecanismo de producción más frecuente: accidentes en motocicleta (41,2%), seguido de atropellados (29,4%). En cuanto a la clasificación la mayor parte fue tipo I de Fraser (68,8%). El tratamiento quirúrgico definitivo se aplicó entre el 5° y 14° día en el 73.3%, mayormente usando clavos centro medulares en fémur y tibia. Los resultados del tratamiento fueron: excelentes 40%, buenos 33.3%, regulares 20% y pobres en el 6,6% según la escala de Karlstrom y Olerud. Las lesiones asociadas: TEC (80%), fracturas de pelvis (60%), trauma abdominal cerrado (60%) y trauma de tórax (33,3%). Dentro de las complicaciones, un paciente falleció por fallamultiorgánica, otro concluyó en amputación, y cinco presentaron infección.Por lo que se concluye que en general los aspectos relacionados con esta patología, su presentación y tratamiento en nuestro medio, son similares a los que se encuentran descritos en la literatura médica.
Gender differentiation of the chemoreflex during growth at high altitude: functional and neurochemical studies
(American Physiological Society, 2000) Vincent Joseph; Jorge Soliz; J. M. Pequignot; B. Semporé; J. M. Cottet-Émard; Y. Dalmaz; R. Favier; Hilde Spielvogel; J. M. Pequignot
The effect of chronic hypoxia on gender differences in physiology and neurochemistry of chemosensory pathways was studied in prepubertal and adult rats living at sea level (SL; Lyon, France) or at high altitude (HA; La Paz, Bolivia, 3,600 m). HA adult rats had higher hematocrit (Ht%), Hb concentration, resting ventilatory rate (Ve(100)), and higher tyrosine hydroxylase (TH) activity in carotid bodies (CB) than SL animals. At HA and SL, adult females had lower Ht% (46.0 +/- 0.8 vs. 50.4 +/- 0.6% at HA, P < 0.05 and 43.8 +/- 0.9 vs. 47.1 +/- 0.8% at SL, P < 0.05) and Hb (16.1 +/- 0.3 vs. 17.7 +/- 0.2 g/dl at HA, P < 0.05 and 14.5 +/- 0.3 vs. 15.6 +/- 0.1 g/dl at SL, P < 0.05) than males. Females had higher Ve(100) [170 +/- 19 vs. 109 +/- 7 ml. min(-1). 100 g(-1) at HA, P < 0.05 and 50 +/- 3 vs. 40 +/- 2 ml. min(-1). 100 g(-1) at SL, not significant (NS)] and lower CB-TH activity (1.40 +/- 0.2 vs. 3.87 +/- 0.6 pmol/20 min at HA, P < 0.05 and 0.52 +/- 0.1 vs. 0.68 +/- 0.1 pmol/20 min at SL; NS) than males at HA only. The onset of hypoxic ventilatory response during development was delayed at HA. Prepubertal HA females had higher Ve(100) than males (2 wk old, +47%) and higher CB-TH activity (3 wk old, +51%). Medullary noradrenergic groups were sex dimorphic during development at SL. Rats raised at HA had a drop of TH activity between the second and the third postnatal week in all medullary groups. In conclusion, our data support the hypothesis that the CB is the major site for sexual differentiation of the ventilatory control. Ventilatory differences appeared before puberty, and the animals bred at HA had profound alterations in the developmental process of the chemoreflex and its neural pathways. Some of these alterations are under dependence of the sex of the animal, and there is an important interaction between gender and the hypoxic environmental condition during the developmental period.
High altitude induces a shift from complex I to complex II in the brain mitochondria of newborn and adult mice
(The Company of Biologists, 2025) Maud Demarest; Fernanda Aliaga‐Raduán; Christian Arias‐Reyes; Marcelino Gonzales; Edith M. Schneider Gasser; Jorge Soliz; Vincent Joseph
Species living at high altitude (HA) often exhibit optimized oxygen utilization at adulthood; however, the plasticity of metabolic pathways during postnatal development remains unclear. Because mice, but not rats, are commonly found at HA, we investigated mitochondrial oxygen consumption rates (OCR) in the cerebral cortex of both species across postnatal development and at adulthood at sea level (SL; Quebec, Canada) under normoxia or hypoxia (13.5% O2), and at HA (La Paz, Bolivia, 3600 m) after 50 generations of residency. At postnatal day (P)7, P14 and P21 and in adults (P60-90), fresh tissue samples were used to assess mitochondrial OCR under states of proton LEAK (OCRLEAK(N)) and oxidative phosphorylation (OXPHOS) using substrates for complex I (N pathway - OCRN), complex II (S pathway - OCRS) and complexes I+II (NS pathways - OCRNS). Our results showed: (1) at HA, rats exhibit higher OCR at P7, P14 and adulthood compared with their SL counterparts, and (2) HA residency induces a shift from the N pathway to the S pathway at all ages in mice. Finally, these responses were absent in SL animals exposed to postnatal hypoxia, highlighting the importance of studying HA-living species. These findings emphasize key metabolic shifts, with implications for understanding responses to hypoxia in species showing divergent success at HA.