ARTÍCULOS CIENTÍFICOS DE DOCENTES INVESTIGADORES

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Aquatic macroinvertebrate trophic guilds, functional feeding groups, and water quality of an andean urban river
(Universidad Nacional de San Cristóbal de Huamanga, 2022) Carrasco Badajoz, Carlos Emilio
In the Anthropocene, man has imposed his activities above the natural processes of ecosystems. Rivers have undergone major changes associated with urban centers, so monitoring them is important to determine their status and suitability to provide environmental services. Studies applying the community ecology approach, such as energy ?ow in aquatic macroinvertebrate assemblages, may be appropriate to determine their status and functioning. This study characterized an Andean river that runs across the city of Ayacucho (Peru). Water physicochemical parameters and biotic quality indices were used and compared with the abundance of trophic guild components and functional feeding groups to demonstrate that the latter are at least equally suitable to estimate water quality. The river section studied ranged from 2640 to 2900 m a.s.l. and was monitored in the wet and dry seasons. Six monitoring stations were established according to the extent of the in?uence of the urban center. Water physicochemical variables and macroinvertebrate abundances were determined. A Surber net was used for multihabitat sampling; macroinvertebrates were identi?ed to genus level (in most cases) and counted to estimate relative abundances. Trophic guilds (detritivore, predator, herbivore) were formed using the genus data from identi?cation according to the information available in Argentina, Colombia, Ecuador, Bolivia, and Peru. Functional feeding groups were set based on the classi?cation of families. The sensitivity of trophic metrics was assessed by relating them to environmental variables and the Andean Biotic Index (ABI), the Biological Monitoring Working Party adapted for Colombia (BMWP/Col.), and the Ephemeroptera, Plecoptera, Trichoptera (EPT) indices. Environmental variables and biotic indices increased signi?cantly in the most impacted stations, where the abundance of most taxa decreased. The components of trophic guilds and functional groups varied, and those feeding on ?ne particles increased in sites with a higher urban impact. The metrics based on trophic characteristics were highly correlated with the BMWP/Col and ABI indices. Therefore, these indices can be used to estimate river water quality and provide information on its functioning.
Detection of Epileptic Seizures Based-on Channel Fusion and Transformer Network in EEG Recordings
(Universidad Nacional de San Cristóbal de Huamanga, 2023) Lagos Barzola, Manuel Avelino
According to the World Health Organization, epilepsy affects more than 50 million people in the world, and specifically, 80% of them live in developing countries. Therefore, epilepsy has become among the major public issue for many governments and deserves to be engaged. Epilepsy is characterized by uncontrollable seizures in the subject due to a sudden abnormal functionality of the brain. Recurrence of epilepsy attacks change people’s lives and interferes with their daily activities. Although epilepsy has no cure, it could be mitigated with an appropriated diagnosis and medication. Usually, epilepsy diagnosis is based on the analysis of an electroencephalogram (EEG) of the patient. However, the process of searching for seizure patterns in a multichannel EEG recording is a visual demanding and time consuming task, even for experienced neurologists. Despite the recent progress in automatic recognition of epilepsy, the multichannel nature of EEG recordings still challenges current methods. In this work, a new method to detect epilepsy in multichannel EEG recordings is proposed. First, the method uses convolutions to perform channel fusion, and next, a self-attention network extracts temporal features to classify between interictal and ictal epilepsy states. The method was validated in the public CHB-MIT dataset using the k-fold cross-validation and achieved 99.74% of specificity and 99.15% of sensitivity, surpassing current approaches.
Dodonaea viscosa Jacq. Induces cytotoxicity, antiproliferative activity, and cell death in colorectal cancer cells via regulation of caspase 3 and p53
(Universidad Nacional de San Cristóbal de Huamanga, 2023) Peña Rojas, Gilmar; Andía Ayme, Vidalina
Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide and is the second leading cause of cancer-related death due to an insuf?ciency prognosis and is generally diagnosed in the last step of development. The Peruvian ?ora has a wide variety of medicinal plants with therapeutic potential in several diseases. Dodonaea viscosa Jacq. is a plant used to treat in?ammatoryprocessaswellas gastrointestinal diseases. The aim of this study was to examine the cytotoxic, antiproliferative, and cell death-inducing effects of D. viscosa on colorectal cancer cells (SW480 and SW620). The hydroethanolic extract was obtained by maceration at 70% ethanol, the phytochemical constituents were identi?ed by LC-ESI-MS.D. viscosa revealed 57 compounds some of them are: isorhamnetin, kaempferol, quercetin, methyl dodovisate B, hardwickiic acid, viscosol, and dodonic acid. Regarding the antitumoral activity, D. viscosa induced cytotoxic and antiproliferative activity in both SW480 and SW620 cancer cells, accompanied with, important changes in mitochondrial membrane potential, formation of the Sub G0/G1 population and increasing levels of apoptotic biomarkers (caspase 3 and the tumor suppressor protein p53) in the metastatic derivative cell line (SW620), suggesting an intrinsic apoptotic process after the treatment with the hydroethanolic extract of D. viscosa.
Efecto de la suplementación con bacterias ácido-lácticas sobre los parámetros productivos en cuyes (Cavia porcellus) de engorde, Ayacucho - Perú
(Universidad Nacional de San Cristóbal de Huamanga, 2023) Quijano Pacheco, Wilber Samuel; Andía Ayme, Vidalina; Peña Rojas, Gilmar
Con el objetivo de evaluar la suplementación con bacterias ácido-lácticas en las raciones de cuyes (Cavia porcellus) de engorde sobre los parámetros productivos, se planteó la experiencia bajo el diseño estadístico completo al azar con arreglo factorial (3T x 3D): tratamientos: T1 (Lactobacillus casei), T2 (L. acidophilus) y T3 (mezcla de L. casei y L. acidophilus) y, tres dosis: 0, 50 y 100 ml (10? UFC ml??) que se ofreció mezclando al alimento. En todos los casos con tres repeticiones y 3 cuyes como unidad experimental, para la comparación de medias se utilizó la prueba de contraste de Tukey, se experimentó con 108 cuyes machos con dos semanas de nacidos. El tiempo de evaluación fue 54 días. Los resultados para consumo de alimento e índice de conversión alimenticia fueron no significativos (p<0,05). Sin embargo, para el peso vivo y ganancia de peso estadísticamente fueron significativos y con la prueba de Tukey la mejor dosis fue de 50 ml, así como para el porcentaje de carcasa. Para la retribución económica el costo de alimento fue similar para todos los tratamientos y dosis. No obstante, numéricamente el uso de los microorganismos favorece para la obtención de cuyes con mejores pesos comerciales para la venta.
Effect of Naphthaleneacetic Acid (NAA) and 6-Benzylamino Purine (BAP) on In-Vitro Propagation of "Mashua" (Tropaeolum tuberosum Ruíz & Pavón) Morphotypes from Peru
(Universidad Nacional de San Cristóbal de Huamanga, 2023) Andía Ayme, Vidalina; Peña Rojas, Gilmar; Pereda Medina, Alex
Background: Tropaeolum tuberosum Ru?z & Pavón “mashua” is a native species of the central Andes and different propagation methods in vitro have been evaluated. However, this research has studied the in vitro propagation of 15 mashua (Tropaeolum tuberosum Ruíz & Pavón) morphotypes from the Ayacucho and Apurímac regions (Peru) Objective: To evaluate the effect of the additives naphthaleneacetic acid (NAA) and 6-benzylamino purine (BAP) on the micro-propagation rate of T. tuberosum. Material and Methods: For in vitro establishment, seedlings were used after disinfection with sodium hypochlorite, propagated in Murashige and Skoog (MS) medium. For the evaluation of the effect of NAA and BAP additives, nodes were isolated from in vitro seedlings after 30 days of cultivation and transferred to MS medium supplemented with 3% sucrose, pH 5.6 and 7 g/L of agar according to T1 (MS + NAA 1ppm) and T2 (MS + BAP 1ppm) treatments. The samples were cultivated for 28 days at 19 °C ± 2 °C with photoperiods of 16 h/light and 8 h/darkness. Results: After evaluating 20 repetitions for each of the three treatments, the addition of NAA or BAP does not improve the micropropagation rate of practically all the morphotypes studied. Furthermore, BAP behaved as an inhibitor of the development of mashua seedlings. Conclusion: The best micropropagation medium of Tropaeolum tuberosum Ruíz & Pavón (mashua) is the basic Murashige and Skoog (MS) medium without the NAA or BAP additives.
Foliar transcriptomes reveal candidate genes for late blight resistance in cultivars of diploid potato Solanum tuberosum L. Andigenum Group
(Universidad Nacional de San Cristóbal de Huamanga, 2023) De La Cruz Lapa, Germán Fernando
Characterization of major resistance (R) genes to late blight (LB) - caused by the oomycete Phytophthora infestans - is very important for potato breeding. The objective of this study was to identify novel genes for resistance to LB from diploid Solanum tuberosum L. Andigenum Group (StAG) cultivar accessions. Using comparative analysis with a edgeR bioconductor package for differential expression analysis of transcriptomes, two of these accessions with contrasting levels of resistance to LB were analyzed using digital gene expression data. As a result, various differentially expressed genes (P ? 0.0001, Log? FC ? 2, FDR < 0.001) were noted. The combination of transcriptomic analysis provided 303 candidate genes that are overexpressed and underexpressed, thereby giving high resistance to LB. The functional analysis showed differential expression of R genes and their corresponding proteins related to disease resistance, NBS-LRR domain proteins, and speci?c disease resistance proteins. Comparative analysis of speci?c tissue transcriptomes in resistant and susceptible genotypes can be used for rapidly identifying candidate R genes, thus adding novel genes from diploid StAG cultivar accessions for host plant resistance to P. infestans in potato.
Improved Production of Mashua (Tropaeolum tuberosum) Microtubers MAC-3 Morphotype in Liquid Medium Using Temporary Immersion System (TIS-RITA®)
(Universidad Nacional de San Cristóbal de Huamanga, 2022) Peña Rojas, Gilmar; Andía Ayme, Vidalina; Carhuaz Condori, Roxana
Essential molecules are embedded within the millenary crop Tropaeolum tuberosum (mashua); these compounds are critical for the Andean people’s traditional diet and extensively utilized by the pharmaceutical industry in Peru. In the Andean region, conventional cropping techniques generate microtubers susceptible to a viral infection, which substantially endangers mashua’s production. Therefore, we developed an innovative in vitro technique condition for enhancing the agriculture process for micro tubers production. The temporary immersion system (TIS) permits the production of high-quality microtubers in a reduced space, a lower amount of time, and in large quantities compared with tubers grown under traditional conditions. To obtain T. tuberosum’s microtubers via TIS, we propagated seedlings, utilizing TIS-RITA® vessels. A set of immersion frequency times were evaluated. Interestingly, results showed that immersion at 2 min every 3 h was more bene?cial compared with 2 min every 5 h based on microtubers produced after 10 weeks from the treatments, revealing an ef?cient frequency setting which outputted improved microtubers quality and production.
In silico evaluation of Dodonic Acid from Dodonaea viscosa Jacq on target Proteins from Staphylococcus aureus
(Universidad Nacional de San Cristóbal de Huamanga, 2022) Andía Ayme, Vidalina; Peña Rojas, Gilmar
Dodonaea viscosa Jacq is known as “chamana” in the popular flora of Peru. the traditional medicine uses its leaves as ingredient in fermented beverages from Zea mays and also in external uses for antiinflammatory diseases. The aim was to study the role of dodonic acid against several protein targets of S. aureus. this study was focused on to analyse the role of dodonic acid against S. aureus target proteins such as on sortase-A, DNA gyrase, dihydrofolate reductase (DhFR), clumping factor, dehydrosqualene synthase, and undecaprenyl di-phosphate synthase as a promising candidate molecule. the docking analysis of dodonic acid showed the best docking score energy on S. aureus undecaprenyl diphosphate synthase with -11.2 kcal/mol and demonstrated to be a very stable molecule at physiological conditions during the molecular dynamic for 50 ns. As conclusion, the extract demonstrated to be active against S. aureus and dodonic acid might be a promising molecule acting on the S. aureus undecaprenyl diphosphate synthase.
Microrganismos acido lácticos y levaduras como suplemento en las raciones para el engorde de cuyes (Cavia porcellus) Ayacucho, Perú
(Universidad Nacional de San Cristóbal de Huamanga, 2022) Quijano Pacheco, Wilber Samuel; Andía Ayme, Vidalina; Peña Rojas, Gilmar
Los microorganismos ácido lácticos poseen un efecto benéfico en el engorde de los cuyes, al mejorar la degradación de la materia orgánica y prevenir la salmonelosis. El objetivo fue evaluar los microrganismos acido lácticos y levaduras como suplemento en las raciones para el engorde de cuyes (Cavia porcellus) en Ayacucho. Se activaron las bacterias en caldo lactosado a 37°C por 48 horas en anaerobiosis, a través de diluciones consecutivas se sembró en agar Rogosa sharpe incubándose a 37°C por 24 a 48 horas para recuento del número de células vivas/ml. Se utilizaron 20 gazapos machos destetados con tamaño y peso homogéneos. Se tuvo 5 tratamientos suplementando con bacterias ácido lácticas al alimento balanceado: T1 (Lactobacillus acidophilus), T2 (Lactobacillus casei), T3 (Lactobacillus acidophilus y Lactobacillus casei) y T5 (testigo), brindándose a libre discreción y alfalfa al 10% de su peso vivo más agua. Como unidad experimental se planteó bajo el diseño completamente randomizado con 5 tratamientos, 2 repeticiones y 2 cuyes. Los resultados mostraron que para el peso vivo y la ganancia de peso resultaron no significativos (p<0.05) y para el consumo de alimento y la conversión alimenticia fueron significativas. Por la prueba de Tukey resultó que los tratamientos con la combinación T3 Lactobacillus acidophilus + Lactobacillus casei y T2 Lactobacillus casei fueron mejores lográndose peso comercial para el mercado en ocho semanas de tratamiento, además mejores rendimientos de carcasa. Con ello se puede intuir que los microorganismos influyen positivamente en el desarrollo de los cuyes.
Preliminary Assessment of Tara Gum as a Wall Material: Physicochemical, Structural, Thermal, and Rheological Analyses of Different Drying Methods
(Universidad Nacional de San Cristóbal de Huamanga, 2024) De La Cruz Lapa, Germán Fernando
Tara gum, a natural biopolymer extracted from Caesalpinia spinosa seeds, was investigated in this study. Wall materials were produced using spray drying, forced convection, and vacuum oven drying. In addition, a commercial sample obtained through mechanical methods and direct milling was used as a reference. The gums exhibited low moisture content (8.63% to 12.55%), water activity (0.37 to 0.41), bulk density (0.43 to 0.76 g/mL), and hygroscopicity (10.51% to 11.42%). This allows adequate physical and microbiological stability during storage. Polydisperse particles were obtained, ranging in size from 3.46 µm to 139.60 µm. Fourier transform infrared spectroscopy characterisation confirmed the polysaccharide nature of tara gum, primarily composed of galactomannans. Among the drying methods, spray drying produced the gum with the best physicochemical characteristics, including higher lightness, moderate stability, smaller particle size, and high glass transition temperature (141.69 ?C). Regarding rheological properties, it demonstrated a non-Newtonian pseudoplastic behaviour that the power law could accurately describe. The apparent viscosity of the aqueous dispersions of the gum decreased with increasing temperature. In summary, the results establish the potential of tara gum as a wall material applicable in the food and pharmaceutical industries.
The Antioxidant Activity of Atomized Extracts of the Leaves and Stems of Cnidoscolus diacanthus (Pax& K. Hoffm.) J.F. Macbr. from Peru and Their Effect on Sex Hormone Levels in Rats
(Universidad Nacional de San Cristóbal de Huamanga, 2024) Tinco Jayo, Johnny Aldo; Enciso Roca, Edwin Carlos
In this research, we aimed to determine the antioxidant activity of an atomized extract of Cnidoscolus diacanthus (Pax & K. Hoffm.) J.F. Macbr., known in Peru as “huanarpo hembra”, and its effect on sex hormone levels. Its phytochemical profile was determined using liquid chromatography–mass spectrometry (LC–MS), while its total phenol content (TPC) and total flavonoids (TFs) were determined using the Folin-Ciocalteu method and the aluminum chloride method. Its antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), the radical 2,2-azino-bis-3-ethylbenzthiazolin-6 sulfonic acid (ABTS), and ferric-reducing antioxidant power (FRAP). The biological activity of C. diacanthus and its effect on sexual hormones were determined in Holtzman rats of both sexes. Phytochemical analysis revealed the presence of flavonoids and phenolic compounds in its leaves and stems, mainly rutin, quercetin, chlorogenic acid, and genistein. However, the stem extract contained higher total phenol (464.38± 4.40 GAE/g) and flavonoid (369.17± 3.16 mg QE/g of extract) contents than the leaf extract (212.38± 3.19 mg GAE/g and 121.49± 2.69 mg QE/g). For DPPH, ABTS, and FRAP, the Trolox-equivalent antioxidant capacity (TEAC) was 597.20 ± 5.40 µmol/g, 452.67 ± 5.76 µmol/g, and 535.91 ± 1.56 µmol/g, respectively, for the stems, while for the leaves, it was 462.39± 3.99 µmol/g, 202.32± 5.20 µmol/g, and 198.13± 1.44 µmol/g, respectively. In terms of the values for hormonal levels, at a dose of 100 mg/kg of the extract, testosterone levels of 1.430 ng/mL (with the leaf extract) and 1.433 ng/mL (with the stem extract), respectively, were found in the male rats. Regarding estradiol levels, in the female rats, these were 10.425 ng/mL (leaf extract) and 8.775 ng/mL (stem extract), while their levels of luteinizing hormone were 0.320 mIU/mL (leaf extract) and 0.273 mIU/mL (stem extract). For the follicle-stimulating hormone, levels of 0.858 mIU/mL (leaf extract) and 0.840 mIU/mL (stem extract) were found in the female rats, and levels of 0.220 mIU/mL (leaf extract) and 0.200 mIU/mL (stem extract) were found in the male rats. It is concluded that the C. diacanthus stem extract had a greater antioxidant capacity than the leaf extract, while both extracts had a superior effect on the sex hormone levels in the female rats compared to the male rats.

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