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"Ramirez, Rocio"
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Variations in anxiety and emotional support among first-year college students across different learning modes (distance and face-to-face) during COVID-19
by
Sharma, Sonam
,
Ramírez-Martínez, Flor Rocío
,
Leiner, Marie
in
Anxiety
,
Anxiety Disorders
,
Biology and Life Sciences
2024
College students with more emotional support experience lower levels of anxiety and other psychosocial and behavioral problems. During the COVID-19 pandemic, the emotional well-being of college students was additionally challenged by an abrupt shift to distance learning followed by a return to face-to-face classes. In this exploratory study, we compared the levels of perceived emotional support and anxiety among incoming first-year undergraduate students, prior to starting classes, which included different learning modes in five semesters of instruction from 2021–2023 (three distance semesters and two face-to-face semesters). Data from 8659 undergraduate students were extracted from a Mexican state university database, corresponding to students’ responses collected during new student orientation week. Participants were students in the arts and humanities (9.7%), social and legal sciences (38%), life and health sciences (28.9%), and engineering and architecture (23.4%). Anxiety levels were measured with the GAD-7 scale, and emotional support was measured using a subscale of the PERACT-R (To go through with resilience) inventory. Comparisons of emotional support and anxiety scores among semesters revealed highly significant differences with small effect sizes. Anxiety levels increased significantly with mean average of 6.65 SD(5.52) during the baseline measure to the highest in 2022–2 to 7.53 SD(5.3) and Emotional Support decreased systematically each semester from baseline mean = 8.03 SD(2.0) to the lowest 7.52 SD(1.8) in 2022–2. The results show that a return to face-to-face classes was associated with increased anxiety levels, whereas levels of emotional support systematically decreased across the five semesters. MANOVA analysis revealed significant differences in anxiety and emotional support scores between semesters, with peaks during the learning mode semester that students returned to face-to-face classes after distance learning even after adjusting for gender. Given that the effect of emotional support on anxiety may be related to success in future educational and professional activities, it is important to develop interventions to restore and increase college students’ emotional support levels and develop anxiety management strategies.
Journal Article
Removal of hydrogen sulfide from biogas by adsorption and photocatalysis: a review
by
Fonseca-Bermúdez, Óscar Javier
,
Moreno-Piraján, Juan Carlos
,
Giraldo, Liliana
in
Adsorbents
,
Adsorption
,
Analytical Chemistry
2023
Biogas is a renewable fuel produced from modern biomass, yet biogas contains traces of hydrogen sulfide, a toxic compound, that must be removed before biogas usage. Here we review the removal of hydrogen sulfide by biological treatment, chemical treatment, porous solid treatment and photocatalysis. Adsorption and photocatalysis methods are compared by figures of merit calculations. Adsorption is used commercially but is limited by the lifespan of adsorbent materials. Photocatalysis appears as an affordable alternative, and the combination of adsorption and photocatalysis is promising. The figure of merit calculation appears as a good indicator of the performance of adsorbent materials and photocatalysts.
Journal Article
Tumor genetic alterations and features of the immune microenvironment drive myelodysplastic syndrome escape and progression
by
Campo, Laura N
,
Amanda Rocío González-Ramírez
,
Hernández, Francisca
in
Acute myeloid leukemia
,
CD34 antigen
,
CD4 antigen
2019
The transformation and progression of myelodysplastic syndromes (MDS) to secondary acute myeloid leukemia (sAML) involve genetic, epigenetic, and microenvironmental factors. Driver mutations have emerged as valuable markers for defining risk groups and as candidates for targeted treatment approaches in MDS. It is also evident that the risk of transformation to sAML is increased by evasion of adaptive immune surveillance. This study was designed to explore the immune microenvironment, immunogenic tumor-intrinsic mechanisms (HLA and PD-L1 expression), and tumor genetic features (somatic mutations and altered karyotypes) in MDS patients and to determine their influence on the progression of the disease. We detected major alterations of the immune microenvironment in MDS patients, with a reduced count of CD4+ T cells, a more frequent presence of markers related to T cell exhaustion, a more frequent presence of myeloid-derived suppressor cells (MDSCs), and changes in the functional phenotype of NK cells. HLA Class I (HLA-I) expression was normally expressed in CD34+ blasts and during myeloid differentiation. Only two out of thirty-six patients with homozygosity for HLA-C groups acquired complete copy-neutral loss of heterozygosity in the HLA region. PD-L1 expression on the leukemic clone was also increased in MDS patients. Finally, no interplay was observed between the anti-tumor immune microenvironment and mutational genomic features. In summary, extrinsic and intrinsic immunological factors might severely impair immune surveillance and contribute to clonal immune escape. Genomic alterations appear to make an independent contribution to the clonal evolution and progression of MDS.
Journal Article
Free Radical-Scavenging Capacities, Phenolics and Capsaicinoids in Wild Piquin Chili (Capsicum annuum var. Glabriusculum)
by
González-Hernández, Víctor Arturo
,
Martínez-Ávila, Guillermo C. G.
,
Torres-Castillo, Jorge Ariel
in
Capsaicin
,
capsaicinoids
,
Capsicum - chemistry
2018
The total phenolic compounds content, free radical-scavenging capacity and capsaicinoid content in populations of wild Piquin chili (C. annuum) were studied. Aqueous and hydroalcoholic extracts from nine ecotypes were evaluated. High contents of phenolic compounds and free radical-scavenging capacities were observed for both extracts; however, the values that were found for the hydroalcoholic phase were substantially higher. LC-MS analysis allowed for the detection of 32 compounds, where apigenin-8-C-glucoside followed by vanillic acid 1-O-β-o-glucopyranosylester (Isomer I or II) and 7-ethoxy-4-methylcoumarin were the most widely distributed; they were found in more than 89% of the ecotypes. The diversity of identified phenolic compounds was different among ecotypes, allowing them to be distinguished by chemical diversity, free radical-scavenging capacities and heat Scoville units. The total capsaicinoid content was higher in Population I (23.5 mg/g DW) than in Populations II and III, which had contents of 15.3 and 10.7 mg/g DW, respectively. This variability could lead to phytochemical exploitation and the conservation of the natural populations of wild chili.
Journal Article
Upper-Room Ultraviolet Light and Negative Air Ionization to Prevent Tuberculosis Transmission
by
Navincopa, Marcos
,
Evans, Carlton A
,
Friedland, Jon S
in
Acquired immune deficiency syndrome
,
AIDS
,
Air Ionization
2009
Background: Institutional tuberculosis (TB) transmission is an important public health problem highlighted by the HIV/AIDS pandemic and the emergence of multidrug- and extensively drug-resistant TB. Effective TB infection control measures are urgently needed. We evaluated the efficacy of upper-room ultraviolet (UV) lights and negative air ionization for preventing airborne TB transmission using a guinea pig air-sampling model to measure the TB infectiousness of ward air. Methods and Findings: For 535 consecutive days, exhaust air from an HIV-TB ward in Lima, Perú, was passed through three guinea pig air-sampling enclosures each housing approximately 150 guinea pigs, using a 2-d cycle. On UV-off days, ward air passed in parallel through a control animal enclosure and a similar enclosure containing negative ionizers. On UV-on days, UV lights and mixing fans were turned on in the ward, and a third animal enclosure alone received ward air. TB infection in guinea pigs was defined by monthly tuberculin skin tests. All guinea pigs underwent autopsy to test for TB disease, defined by characteristic autopsy changes or by the culture of Mycobacterium tuberculosis from organs. 35% (106/304) of guinea pigs in the control group developed TB infection, and this was reduced to 14% (43/303) by ionizers, and to 9.5% (29/307) by UV lights (both p < 0.0001 compared with the control group). TB disease was confirmed in 8.6% (26/304) of control group animals, and this was reduced to 4.3% (13/303) by ionizers, and to 3.6% (11/307) by UV lights (both p < 0.03 compared with the control group). Time-to-event analysis demonstrated that TB infection was prevented by ionizers (log-rank 27; p < 0.0001) and by UV lights (log-rank 46; p < 0.0001). Time-to-event analysis also demonstrated that TB disease was prevented by ionizers (log-rank 3.7; p = 0.055) and by UV lights (log-rank 5.4; p = 0.02). An alternative analysis using an airborne infection model demonstrated that ionizers prevented 60% of TB infection and 51% of TB disease, and that UV lights prevented 70% of TB infection and 54% of TB disease. In all analysis strategies, UV lights tended to be more protective than ionizers. Conclusions: Upper-room UV lights and negative air ionization each prevented most airborne TB transmission detectable by guinea pig air sampling. Provided there is adequate mixing of room air, upper-room UV light is an effective, low-cost intervention for use in TB infection control in high-risk clinical settings.
Journal Article
Drying Effects on Phenolics and Free Radical-Scavenging Capacity of Rhus pachyrrhachis and Rhus virens Used in Traditional Medicine
by
Juárez-Aragón, María Cruz
,
Guerra-Pérez, Antonio
,
Mora-Olivo, Arturo
in
Acids
,
Antioxidants
,
Desiccation
2019
Rhus pachyrrhachis and Rhus virens are medicinal plant species with important uses in northeastern Mexico. They belong to a complex of Rhus species called “lantriscos”, which are used for medicinal applications. The medicinal effects of these species are based on traditional use, however, they require phytochemical research to validate their medicinal properties, as well as structural characterization for their correct identification during the collecting practice and uses. The phytochemical potential of aqueous extracts from R. pachyrrhachis and R. virens was analyzed by the quantification of total phenolic content (TPC), free radical-scavenging potential, and total flavonoids, with a comparison of four drying methods, and some phenolic compounds were identified. Furthermore, the stems and leaves of both species were anatomically characterized to establish a differentiation. R. pachyrrhachis and R. virens showed similar values of phytochemical contents, although the TPC content (0.17 mg of gallic acid equivalent per gram of dry weight, GAE/g DW) was higher in R. virens. The drying method used affected the metabolite contents, and this behavior was related to the species. Regarding the phenolic compounds, shikimic acid, galloylquinic acid, and gallic acid were identified in both species, however, quinic acid was only found in Rhus pachyrrhachis, while vanillic acid O-hexoside was identified only in Rhus virens. At the anatomical level, the pubescence associated with trichomes on the leaves of Rhus pachyrrhachis was highlighted as the main differential characteristic.
Journal Article
Adsorption and Photocatalytic Study of Phenol Using Composites of Activated Carbon Prepared from Onion Leaves (Allium fistulosum) and Metallic Oxides (ZnO and TiO2)
by
Hernández-Barreto, Diego Felipe
,
Rodriguez-Estupiñán, Jenny Paola
,
Moreno-Piraján, Juan Carlos
in
Activated carbon
,
Adsorption
,
Catalysis
2020
The aim of this study was to evaluate and compare the adsorption and photocatalytic activity of activated carbon-based photocatalysts. Titanium dioxide (TiO2) and zinc oxide (ZnO) were chosen as semiconductors to prepare composites with activated carbon by the wet impregnation method. Activated carbon was prepared using as starting material onion leaves (Allium fistulosum) and as activating agent phosphoric acid (H3PO4). Photooxidation and batch adsorption of phenol was studied to compare the efficiency of the materials prepared. The results showed that the composite AC–TiO2 has a greater photocatalytic activity and a better adsorption capacity compared to AC–ZnO composite.
Journal Article
Emerging trends in invasive and noninvasive isolates of Streptococcus agalactiae in a Latin American hospital: a 17-year study
by
Crespo-Ortiz, Maria del Pilar
,
Recalde-Bolaños, Monica
,
Vélez-Londoño, Juan Diego
in
Adolescent
,
Adult
,
Aged
2014
Streptococcus agalactiae or group B Streptococcus (GBS) has been recognized as a lethal pathogen in neonates worldwide. S. agalactiae infections also severely affect pregnant women and immunosuppressed adults with substantial attributable morbidity and mortality. However, in Latin America, studies on the epidemiology and behaviour of S. agalactiae infections remain limited.
To better understand the behaviour of S. agalactiae infections in our region, we conducted a retrospective study to phenotypically describe S. agalactiae isolates collected in one of the largest hospitals in Colombia at two time periods: 1994-2001 and 2004-2012. The isolates were identified by biochemical analysis and tested for antimicrobial susceptibility.
In 1994-2001 a total of 201 S. agalactiae isolates were found in urine 38.3%, vaginal exudates 27.8%, soft tissue 12.9%, and blood 8.5%. Susceptibility to ampicillin or penicillin was 94% whereas resistance to erythromycin and clindamycin were 2.8% and 5.2% respectively. In total 46 culture-positive cases of invasive infections were reported, 11 (24%) in neonates and 35 (76%) in adults. In 2004-2012 a total of 671 isolates were found in urine 47.8%, vaginal exudates 32.6%, soft tissue 2.7% and blood 9%. Susceptibility rates to ampicillin and penicillin were 98% whereas resistance to erythromycin and clindamycin were 12.5% and 9.4%. A total of 95 severe infections were reported: 12 (12.6%) were in neonates, 5 (5.3%) in children and 78 (82.1%) in adults. Over the 17-year study period the averaged prevalence of invasive S. agalactiae isolates was 17.4%. The estimated incidence for neonatal infections was 1.34 per 1000 livebirths (0.99 × 1000 livebirths for early- onset disease and 0.35 × 1000 livebirths for late- onset disease) whereas for non-pregnant adults the estimated incidence was 0.75 × 1000 admissions.
A remarkable increase in bloodstream infections in immunosuppressed adults and a shift to early neonatal S. agalactiae infections were seen over time. We also found an increase in S. agalactiae resistance to erythromycin and clindamycin during the study period, and the emergence of penicillin-nonsusceptible isolates. Our findings are consistent with the global trends described elsewhere, reinforcing the need for S. agalactiae control measures in our region.
Journal Article
Human T-cell receptor triggering requires inactivation of Lim kinase-1 by Slingshot-1 phosphatase
by
Martín-Cófreces, Noa Beatriz
,
Aguilar-Sopeña, Óscar
,
Roda-Navarro, Pedro
in
13/1
,
13/109
,
13/31
2024
Actin dynamics control early T-cell receptor (TCR) signalling during T-cell activation. However, the precise regulation of initial actin rearrangements is not completely understood. Here, we have investigated the regulatory role of the phosphatase Slingshot-1 (SSH1) in this process. Our data show that SSH1 rapidly polarises to nascent cognate synaptic contacts and later relocalises to peripheral F-actin networks organised at the mature immunological synapse. Knockdown of SSH1 expression by CRISPR/Cas9-mediated genome editing or small interfering RNA reveal a regulatory role for SSH1 in CD3ε conformational change, allowing Nck binding and proper downstream signalling and immunological synapse organisation. TCR triggering induces SSH1-mediated activation of actin dynamics through a mechanism mediated by Limk-1 inactivation. These data suggest that during early TCR activation, SSH1 is required for rapid F-actin rearrangements that mediate initial conformational changes of the TCR, integrin organisation and proximal signalling events for proper synapse organisation. Therefore, the SSH1 and Limk-1 axis is a key regulatory element for full T cell activation.
This study identifies a role for the phosphatase Slingshot-1 in controlling LIMK1 and PAK1 signalling to achieve the cytoskeletal rearrangements that facilitate NCK recruitment to the T-cell receptor and downstream signaling.
Journal Article
Optimization of 2-Phenylethanol Production from Sweet Whey Fermentation Using Kluyveromyces marxianus
by
Ramírez-Vargas, María del Rocío
,
Gómez-Aldapa, Carlos A.
,
Cadena-Ramírez, Arturo
in
2-phenylethanol
,
Ammonium sulfate
,
Aroma
2022
The growing demand for natural products benefits the development of bioprocesses to obtain value-added compounds using residues such as sweet whey, which is rich in lactose. The yeast Kluyveromyces marxianus can ferment sweet whey to obtain 2-phenylethanol (2-PhEtOH), which is a superior alcohol with a rose aroma. Such fermentation only requires the addition of L-phenylalanine (precursor) and (NH4)2SO4 (salt). Therefore, it was sought to improve the fermentation conditions to produce 2-PhEtOH, which, in turn, would achieve the maximum decrease in the Chemical Oxygen Demand (COD) of the fermentation medium. With the use of the Response Surface Methodology and the application of a Central Composite Design for optimization, two parameters were evaluated as a function of time: salt concentration and precursor. The experimental data were adjusted to a second order polynomial, identifying that the precursor concentration presents a statistically significant effect. The best conditions were: 4.50 g/L of precursor and 0.76 g/L of salt, with a maximum production of 1.2 g/L (2-PhEtOH) at 48 h and achieving a maximum percentage of COD removal of 76% at 96 h. Finally, the optimal conditions were experimentally validated, recommending the use of the model.
Journal Article