Cold-driven strategies as pre-fermentative techniques on winemaking: A review.

As a pre-fermentative practice, cold may facilitate the extraction of grape compounds, resulting in differentiated wines. To explore the potential of these practices, extensive research has been conducted on scientific publications since 2004. There are four main ways to apply cold in pre-fermentative practices: ice wine production, berry freezing, cold maceration of grape must, and cryoconcentration of grape must. Scientific studies investigating these techniques report that certain compounds, especially phenolic compounds, can be elevated in the must, resulting in wines with increased levels of compounds crucial for wine quality. However, the outcomes reported in the literature are often controversial. Various factors influence the results of these practices, such as the mechanical properties of the grape skins, the duration of the processes, and the temperature conditions. Despite these variations, the potential benefits of cold application in winemaking continue to be a significant area of interest for producing high-quality, distinctive wines.

IF1 is a cold-regulated switch of ATP synthase hydrolytic activity to support thermogenesis in brown fat.

While mechanisms controlling uncoupling protein-1 (UCP1) in thermogenic adipocytes play a pivotal role in non-shivering thermogenesis, it remains unclear whether F1Fo-ATP synthase function is also regulated in brown adipose tissue (BAT). Here, we show that inhibitory factor 1 (IF1, encoded by Atp5if1), an inhibitor of ATP synthase hydrolytic activity, is a critical negative regulator of brown adipocyte energy metabolism. In vivo, IF1 levels are diminished in BAT of cold-adapted mice compared to controls. Additionally, the capacity of ATP synthase to generate mitochondrial membrane potential (MMP) through ATP hydrolysis (the so-called "reverse mode" of ATP synthase) is increased in brown fat. In cultured brown adipocytes, IF1 overexpression results in an inability of mitochondria to sustain the MMP upon adrenergic stimulation, leading to a quiescent-like phenotype in brown adipocytes. In mice, adeno-associated virus-mediated IF1 overexpression in BAT suppresses adrenergic-stimulated thermogenesis and decreases mitochondrial respiration in BAT. Taken together, our work identifies downregulation of IF1 upon cold as a critical event for the facilitation of the reverse mode of ATP synthase as well as to enable energetic adaptation of BAT to effectively support non-shivering thermogenesis.

Exploring the efficacy of in-vitro low-temperature plasma treatment on single and multispecies dental cariogenic biofilms.

The primary aim of this study was to investigate the impact of treatment with low-temperature plasma (LTP) for varying exposure durations on a multispecies cariogenic biofilm comprising C. albicans, L. casei, and S. mutans, as well as on single-species biofilms of L. casei and C. albicans, cultured on hydroxyapatite discs. Biofilms were treated with LTP-argon at a 10 mm distance for 30 s, 60 s, and 120 s. Chlorhexidine solution (0.12%) and NaCl (0.89%) were used as positive (PC) and negative controls (NC), respectively. Argon flow only was also used as gas flow control (F). Colony-forming units (CFU) recovery and confocal laser scanning microscopy (CLSM) were used to analyze biofilm viability. LTP starting at 30 s of application significantly reduced the viability of multispecies biofilms by more than 2 log10 in all treated samples (p < 0.0001). For single-species biofilms, L. casei showed a significant reduction compared to PC and NC of over 1 log10 at all exposure times (p < 0.0001). In the case of C. albicans biofilms, LTP treatment compared to PC and NC resulted in a significant decrease in bacterial counts when applied for 60 and 120 s (1.55 and 1.90 log10 CFU/mL, respectively) (p < 0.0001). A significant effect (p ≤ 0.05) of LTP in single-species biofilms was observed to start at 60 s of LTP application compared to F, suggesting a time-dependent effect of LTP for the single-species biofilms of C. albicans and L. casei. LTP is a potential mechanism in treating dental caries by being an effective anti-biofilm therapy of both single and multispecies cariogenic biofilms.

Impact of increased pre-start diet density on broiler chick behavior, corticosterone levels, and performance responses under cold stress during early life.

This study assessed the effects of increased pre-start diet density on the metabolism, crop filling, and overall performance of broilers under cold stress during their initial 14 days of life. Using 576 one-day-old Cobb500 male chicks from 27-week-old breeders, the experiment employed a 2 × 2 arrangement, varying thermal conditions (thermoneutrality or cold stress at 18 °C for 8 h) and pre-start diet composition (21.5% crude protein, 2970 kcal/kg or 22.5%, 3050 kcal/kg). The cold stress group exhibited lower cloacal temperature and decreased crop filling rate during the first two days (P < 0.05). Chick behavior was significantly affected at 1 and 5 days (P < 0.05), and corticosterone levels in serum were higher for the cold stress group at 7 days (P < 0.05). Feed intake at 7 days was lower in the high-density feed group (P < 0.05). No significant interactions were observed for feed intake, body weight gain, or feed conversion ratio at 7 and 35 days (P > 0.05). Cold stress resulted in performance losses, impacting feed conversion and the Productive Efficiency Index. The dense diet influenced performance only within the first week, with subsequent diets showing no effect, suggesting dietary manipulation alone was insufficient to mitigate cold stress-induced losses.

Extraction and Physicochemical Characterization of Hydroxyapatites From Horse Humerus Bones of Different Ages (1, 3, 6, and 8 Years old) Calcined at Low Temperature.

The aim of this work is to investigate the changes in the physicochemical properties of hydroxyapatite (HAp) extracted from horse humerus bones of different ages (1, 3, 6, and 8 years) subjected to low temperature calcination (600°C). Thermal analysis revealed significant mass loss due to water, collagen, organic compounds, carbonates, and age-related magnesium out-diffusion. Higher fat content in older bones contributed to increased mass loss. Phosphorus content remained constant across age groups, while calcium and sodium showed age-related fluctuations. Magnesium levels decreased with age, emphasizing its importance for early bone development. The Ca/P ratio deviated from the stoichiometric values due to additional ions from biogenic sources. Infrared spectroscopy identified functional groups in carbonated HAp, with changes observed before and after calcination. The full width at half maximum (FWHM) of the 961 cm-1 band decreased with age, indicating improved crystalline quality. The molar absorption coefficients provided information on the changes in molecular concentration and emphasized the differences between the age groups. X-ray analysis revealed nanocrystalline HAp in all samples, with crystallite size increasing with age. Rietveld analysis showed that the lattice parameters were affected by the presence of organic material, but the lattice constants remained stable, confirming high crystallinity independent of age. TEM analysis confirmed nanocrystalline structures, with crystallite size increasing with age. SEM images showed the characteristic porosity of calcined HAp, with particle size correlating positively with age. Calcination at 600°C preserved the nanoscale properties and microcrystal formation. Raman spectroscopy confirmed the identity of HAp, with FWHM variations indicating age-related changes in crystalline quality. EHAp1 showed increased FWHM, indicating lower crystalline quality and increased trace element content.

Adaptation strategies of giant viruses to low-temperature marine ecosystems.

Microbes in marine ecosystems have evolved their gene content to thrive successfully in the cold. Although this process has been reasonably well studied in bacteria and selected eukaryotes, less is known about the impact of cold environments on the genomes of viruses that infect eukaryotes. Here, we analyzed cold adaptations in giant viruses (Nucleocytoviricota and Mirusviricota) from austral marine environments and compared them with their Arctic and temperate counterparts. We recovered giant virus metagenome-assembled genomes (98 Nucleocytoviricota and 12 Mirusviricota MAGs) from 61 newly sequenced metagenomes and metaviromes from sub-Antarctic Patagonian fjords and Antarctic seawater samples. When analyzing our data set alongside Antarctic and Arctic giant viruses MAGs already deposited in the Global Ocean Eukaryotic Viral database, we found that Antarctic and Arctic giant viruses predominantly inhabit sub-10°C environments, featuring a high proportion of unique phylotypes in each ecosystem. In contrast, giant viruses in Patagonian fjords were subject to broader temperature ranges and showed a lower degree of endemicity. However, despite differences in their distribution, giant viruses inhabiting low-temperature marine ecosystems evolved genomic cold-adaptation strategies that led to changes in genetic functions and amino acid frequencies that ultimately affect both gene content and protein structure. Such changes seem to be absent in their mesophilic counterparts. The uniqueness of these cold-adapted marine giant viruses may now be threatened by climate change, leading to a potential reduction in their biodiversity.

Mortality risk and burden of aortic aneurysm and dissection attributable to low temperatures: A nationwide case-crossover analysis in Brazil, a predominantly tropical country.

BACKGROUND: Low temperatures are adverse contributors to cardiovascular diseases, but the associations between short-term exposure to cold and the risk of death from aortic dissection and aneurysm remain unclear, particularly in tropical regions. OBJECTIVE: This study was conducted based on 123,951 records of deaths caused by aortic dissection and aneurysms extracted from the national Mortality Information System in Brazil between 2000 and 2019. METHODS: Relative risks and 95 % confidence intervals (CI) for the aortic-related deaths associated with low ambient temperatures were estimated using the conditional logistic model combined with the distributed lag nonlinear model. Subgroup analyses were performed by age group, sex, race, education level, and residential region. Furthermore, this study calculated the number and fraction of aortic-related deaths attributed to temperatures below the temperature threshold to quantify the cold-related mortality burden of aortic diseases. RESULTS: During the study period, aortic-related deaths and mortality rates in Brazil exhibited a steady increase, rising from 4419 (2.66/100,000) in 2000 to 8152 (3.88/100,000) in 2019. Under the identified temperature threshold (26 °C), per 1 °C decrease in daily mean temperature was associated with a 4.77 % (95 % CI: 4.35, 5.19) increase in mortality risk of aortic-related diseases over lag 0-3 days. Females, individuals aged 50 years or older, Asian and Black race, and northern residents were more susceptible to low temperatures. Low temperatures were responsible for 19.10 % (95 % CI: 17.71, 20.45) of aortic-related deaths in Brazil. CONCLUSION: This study highlights that low temperatures were associated with an increased risk of aortic-related deaths, with a remarkable burden even in this predominantly tropical country.

Macauba (Acrocomia aculeata) pulp oil reduces fat accumulation and enhances the lifespan of Caenorhabditis elegans at low temperatures via fat-1- and fat-7-dependent pathway.

Macauba (Acrocomia aculeata) is a Brazilian palm tree whose oil in the pulp is rich in oleic acid and carotenoids. However, its physiological function remains unknown. This study aimed to investigate the effects of macauba pulp oil (MPO) on the metabolic link between lipid metabolism and lifespan using Caenorhabditis elegans (C. elegans). C. elegans were treated with 5.0 mg/mL of MPO for analyzing triglyceride and glycerol accumulation, fatty acid profile, gene expression of lipid and oxidative metabolism proteins under cold (4°C) stress conditions, and lifespan analysis under stress conditions such as cold (4°C), heat (37°C), and oxidative (paraquat) stress. MPO significantly suppressed fat accumulation and increased glycerol (a lipolysis index) and the lifespan of C. elegans at low temperature (4°C). This was accompanied by decreased mRNA levels of the genes involved in lipogenesis (spb-1 and pod-2) and increased levels of the genes involved in fatty acid ß-oxidation (acs-2 and nhr-49) and fat mobilization genes (hosl-1 and aak-2). Additionally, MPO treatment modulated fatty acid pools in C. elegans at low temperatures in that MPO treatment decreased saturated fatty acid levels and shifted the fatty acid profile to long-chain fatty acids. Moreover, the effect of MPO on fat accumulation at low temperatures was abolished in fat-7 mutants, whereas both fat-1 and fat-7 contribute, at least in part, to MPO-elevated survival of C. elegans under cold conditions. PRACTICAL APPLICATION: The results obtained in the present study may contribute to the understanding of the health benefits of consuming macauba pulp oil and consequently stimulate economic growth and the industrial application of this new type of oil, which may result in the creation of new jobs and increased value of small producers.

Quantification of cresols in liquid smoke samples employing liquid-liquid extraction with low-temperature purification and analysis by gas chromatography-mass spectrometry.

Liquid smoke is a food additive and cresols are among its chemical constituents, potentially toxic to human health. Thus, the objective of this study was to develop a method to quantify cresols in liquid smoke. First, the liquid-liquid extraction with low temperature purification (LLE-LTP) was validated for cresols in water, as there are no cresol-free liquid smoke samples. Analyzes were performed by gas chromatography coupled to mass spectrometry in full scan mode. LLE-LTP was subsequently applied in five commercial samples of liquid smoke. Validation results showed that the proposed extraction method was selective for cresols, linear in the range of 0.5 to 35 mg L-1, limit of quantification of 0.5 mg L-1, recovery rate between 90% and 104% and relative standard deviation lower than 10%. The quantification of cresols in liquid smoke samples ranged from 3.0 to 38.3 mg L-1 and the concentration of these chemical contaminants in liquid smoke remained constant for at least 21 days at 25 °C.

Kinin B1 receptor deficiency promotes enhanced adipose tissue thermogenic response to ß3-adrenergic stimulation.

OBJECTIVE AND DESIGN: Kinin B1 receptor (B1R) has a key role in adipocytes to protect against obesity and glycemic metabolism, thus becoming a potential target for regulation of energy metabolism and adipose tissue thermogenesis. MATERIAL OR SUBJECTS: Kinin B1 knockout mice (B1KO) were subjected to acute induction with CL 316,243 and chronic cold exposure. METHODS: Metabolic and histological analyses, gene and protein expression and RNA-seq were performed on interscapular brown adipose tissue (iBAT) and inguinal white adipose tissue (iWAT) of mice. RESULTS: B1KO mice, under acute effect of CL 316,243, exhibited increased energy expenditure and upregulated thermogenic genes in iWAT. They were also protected from chronic cold, showing enhanced non-shivering thermogenesis with increased iBAT mass (~ 90%) and recruitment of beige adipocytes in iWAT (~ 50%). Positive modulation of thermogenic and electron transport chain genes, reaching a 14.5-fold increase for Ucp1 in iWAT. RNA-seq revealed activation of the insulin signaling pathways for iBAT and oxidative phosphorylation, tricarboxylic acid cycle, and browning pathways for iWAT. CONCLUSION: B1R deficiency induced metabolic and gene expression alterations in adipose tissue, activating thermogenic pathways and increasing energy metabolism. B1R antagonists emerge as promising therapeutic targets for regulating obesity and associated metabolic disorders, such as inflammation and diabetes.

Copper resistance in the cold: Genome analysis and characterisation of a PIB-1 ATPase in Bizionia argentinensis.

Copper homeostasis is a fundamental process in organisms, characterised by unique pathways that have evolved to meet specific needs while preserving core resistance mechanisms. While these systems are well-documented in model bacteria, information on copper resistance in species adapted to cold environments is scarce. This study investigates the potential genes related to copper homeostasis in the genome of Bizionia argentinensis (JUB59-T), a psychrotolerant bacterium isolated from Antarctic seawater. We identified several genes encoding proteins analogous to those crucial for copper homeostasis, including three sequences of copper-transport P1B-type ATPases. One of these, referred to as BaCopA1, was chosen for cloning and expression in Saccharomyces cerevisiae. BaCopA1 was successfully integrated into yeast membranes and subsequently extracted with detergent. The purified BaCopA1 demonstrated the ability to catalyse ATP hydrolysis at low temperatures. Structural models of various BaCopA1 conformations were generated and compared with mesophilic and thermophilic homologous structures. The significant conservation of critical residues and structural similarity among these proteins suggest a shared reaction mechanism for copper transport. This study is the first to report a psychrotolerant P1B-ATPase that has been expressed and purified in a functional form.

Genetic diversity analysis and core germplasm bank construction in cold resistant germplasm of rubber trees (Hevea brasiliensis).

The rubber tree, Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell. Arg., is the sole plant worldwide utilized for the commercial production of natural rubber. Following years of breeding, there exists a wide array of germplasm differentiation in rubber trees. The exploration of diversity and population structure within rubber tree germplasm resources, alongside the establishment of core germplasm resources, is instrumental in elucidating the genetic background and facilitating the effective utilization and management of these resources. By employing SNP molecular marker technology, 195 rubber tree resources were amplified, their genetic diversity analyzed, and a fingerprint map was subsequently constructed. Through this process, the cold-resistant core germplasm of rubber trees was identified. The results revealed that the PIC, He, and pi values ranged from 0.0905 to 0.3750, 0.095 to 0.5000, and 0.0953 to 0.5013, respectively. Both group structure analysis and cluster analysis delineated the accessions into two groups, signifying a simple group structure. A core germplasm bank was established with a sampling ratio of 10%, comprising 21 accessions divided into two populations. Population G1 consists of 20 accessions, while population G2 comprises 1 accession. The research findings have led to the creation of a molecular database that is anticipated to contribute to the management and subsequent breeding applications of rubber tree accessions.

Somatosensory alterations after single-unit dental implant immediate loading: A 1-year follow-up study.

OBJECTIVE: This cohort study aimed to assess the incidence of somatosensory alterations after implant surgery using standardized quantitative and qualitative sensory testing. METHODS: 33 participants with single-tooth loss, undergoing immediate implant loading were included. Quantitative Sensory Testing (QST) and Qualitative Sensory Testing (QualST) were conducted at eight time points over a year (baseline to 1 year). Two-Way Repeated Measures ANOVA and post hoc Tukey test were used on QST values and Cochran Q test on QualST. RESULTS: The study revealed significant increase in thermal thresholds overtime. At the operated side, overall Cold Pain Threshold (extraoral: p = 0.030; intraoral: p < 0.001), and Cold Detection Threshold (intraoral: p < 0.001) increased overtime. In contralateral region, maxilla Cold Detection Threshold (extraoral: p = 0.024; intraoral: p = 0.031), Warm Detection Threshold (extraoral: p = 0.026; intraoral: p = 0.047) and overall Cold Pain Threshold (extraoral and intraoral: p < 0.001) also increased. QualST showed extraoral pinprick (p = 0.032) and intraoral pinprick (p = 0.000), cold (p = 0.000) and touch (p = 0.002) stimuli abnormalities overtime. CONCLUSIONS: Somatosensory alterations after implant surgery were detected in both quantitative and qualitative sensory assessments, but rapidly decreased during the first follow-ups, and then continuously until 1-year. CLINICAL SIGNIFICANCE: This study provides clinical and controlled evidence on the real effect of the somatosensory alterations overtime, leading to a better understanding of neurosensory behaviour after single-tooth dental implant rehabilitation.

Effective brain connectivity related to non-painful thermal stimuli using EEG.

Understanding the brain response to thermal stimuli is crucial in the sensory experience. This study focuses on non-painful thermal stimuli, which are sensations induced by temperature changes without causing discomfort. These stimuli are transmitted to the central nervous system through specific nerve fibers and are processed in various regions of the brain, including the insular cortex, the prefrontal cortex, and anterior cingulate cortex. Despite the prevalence of studies on painful stimuli, non-painful thermal stimuli have been less explored. This research aims to bridge this gap by investigating brain functional connectivity during the perception of non-painful warm and cold stimuli using electroencephalography (EEG) and the partial directed coherence technique (PDC). Our results demonstrate a clear contrast in the direction of information flow between warm and cold stimuli, particularly in the theta and alpha frequency bands, mainly in frontal and temporal regions. The use of PDC highlights the complexity of brain connectivity during these stimuli and reinforces the existence of different pathways in the brain to process different types of non-painful warm and cold stimuli.

Hepatic noradrenergic innervation acts via CREB/CRTC2 to activate gluconeogenesis during cold.

BACKGROUND AND AIM: Although it is well established that hormones like glucagon stimulates gluconeogenesis via the PKA-mediated phosphorylation of CREB and dephosphorylation of the cAMP-regulated CREB coactivators CRTC2, the role of neural signals in the regulation of gluconeogenesis remains uncertain. METHODS AND RESULTS: Here, we characterize the noradrenergic bundle architecture in mouse liver; we show that the sympathoexcitation induced by acute cold exposure promotes hyperglycemia and upregulation of gluconeogenesis via triggering of the CREB/CRTC2 pathway. Following its induction by dephosphorylation, CRTC2 translocates to the nucleus and drives the transcription of key gluconeogenic genes. Rodents submitted to different models of sympathectomy or knockout of CRTC2 do not activate gluconeogenesis in response to cold. Norepinephrine directly acts in hepatocytes mainly through a Ca2+-dependent pathway that stimulates CREB/CRTC2, leading to activation of the gluconeogenic program. CONCLUSION: Our data demonstrate the importance of the CREB/CRTC2 pathway in mediating effects of hepatic sympathetic inputs on glucose homeostasis, providing new insights into the role of norepinephrine in health and disease.

Frost fighters: unveiling the potential of microbial antifreeze proteins in biotech innovation.

Polar environments pose extreme challenges for life due to low temperatures, limited water, high radiation, and frozen landscapes. Despite these harsh conditions, numerous macro and microorganisms have developed adaptive strategies to reduce the detrimental effects of extreme cold. A primary survival tactic involves avoiding or tolerating intra and extracellular freezing. Many organisms achieve this by maintaining a supercooled state by producing small organic compounds like sugars, glycerol, and amino acids, or through increasing solute concentration. Another approach is the synthesis of ice-binding proteins, specifically antifreeze proteins (AFPs), which hinder ice crystal growth below the melting point. This adaptation is crucial for preventing intracellular ice formation, which could be lethal, and ensuring the presence of liquid water around cells. AFPs have independently evolved in different species, exhibiting distinct thermal hysteresis and ice structuring properties. Beyond their ecological role, AFPs have garnered significant attention in biotechnology for potential applications in the food, agriculture, and pharmaceutical industries. This review aims to offer a thorough insight into the activity and impacts of AFPs on water, examining their significance in cold-adapted organisms, and exploring the diversity of microbial AFPs. Using a meta-analysis from cultivation-based and cultivation-independent data, we evaluate the correlation between AFP-producing microorganisms and cold environments. We also explore small and large-scale biotechnological applications of AFPs, providing a perspective for future research.

Cold extraction process for producing a low-alcohol beer, International Pale Lager style: Evaluation and description of flavors using electronic tongue.

Grains germinate, dry, and then undergo crushing before being combined with hot water to yield a sweet and viscous liquid known as wort. To enhance flavor and aroma compounds while maintaining a lower alcohol content, cold water is utilized during wort production without increasing its density. Recent years have witnessed a surge in demand for beverages with reduced alcohol content, reflecting shifting consumer preferences towards healthier lifestyles. Notably, consumers of low-alcohol beers seek products that closely mimic traditional beers. In response, batches of low-alcohol beer were meticulously crafted using a cold extraction method with room temperature water, resulting in a beer with 1.11% alcohol by volume (ABV). Sensory evaluations yielded a favorable score of 27 out of 50, indicating adherence to style standards and absence of major technical flaws. Furthermore, electronic taste profiling revealed a striking similarity between the low-alcohol beer and the benchmark International Pale Lager style, exemplified by commercial beers (5 and 0.03% ABV). Notably, the reduced-alcohol variant boasted lower caloric content compared to both standard and non-alcoholic counterparts. Consequently, the cold extraction approach emerges as a promising technique for producing low-alcohol beers within the International Pale Lager style, catering to evolving consumer preferences and health-conscious trends.

Effect of Swimming at Low Temperature on Uncoupling Protein Gene Expression in Skeletal Muscle of Wistar Rats / Efecto de la Natación a Baja Temperatura sobre la Expresión del Gen de la Proteína de Desacoplamiento en el Músculo Esquelético de Ratas Wistar

SUMMARY: As the economy develops and living standards improve, overweight and obesity are increasingly prevalent. Currently, weight-loss medications are primarily administered orally or intravenously, which can result in poor targeting, low bioavailability, frequent administration, and high toxicity and side effects. The study aimed to address these challenges by preparing polylactic acid- polyethylene glycol staple fibers that carry the browning drug pioglitazone hydrochloride using electrostatic spinning and freeze-cutting techniques. Animal experiments were conducted to test the effectiveness of these fibers. Additionally, the study investigated the expression of uncoupling protein genes in rats exposed to different water temperatures by measuring changes in serum urea nitrogen and mRNA expression levels of skeletal muscle uncoupling protein genes. The physiological and genetic effects of low-temperature swimming exercise on changes in energy metabolism in rats were also analyzed at both the individual and molecular levels. The results revealed that serum urea nitrogen remained more stable in hypothermic swimming rats compared to rats in the swimming group. Furthermore, the study observed an induced up-regulation of uncoupling proteins in the skeletal muscle of Wistar rats in response to external temperature stimulation, and the expression of mRNA for skeletal muscle uncoupling proteins significantly increased as the temperature decreased. And the prepared short nanofibers also had a significant promotive effect on uncoupling protein gene, COX7A1, while suppressing the expression of lipogenic gene.

A medida que la economía se desarrolla y los niveles de vida mejoran, el sobrepeso y la obesidad son cada vez más frecuentes. Actualmente, los medicamentos para bajar de peso se administran principalmente por vía oral o intravenosa, lo que puede resultar en una mala focalización, baja biodisponibilidad, administración frecuente y alta toxicidad y efectos secundarios. El estudio tuvo como objetivo abordar estos desafíos mediante la preparación de fibras cortadas de ácido poliláctico y polietilenglicol que transportan el fármaco pardo clorhidrato de pioglitazona mediante técnicas de hilado electrostático y liofilización. Se realizaron experimentos con animales para probar la eficacia de estas fibras. Además, el estudio investigó la expresión de genes de proteínas desacopladoras en ratas expuestas a diferentes temperaturas del agua midiendo los cambios en el nitrógeno ureico sérico y los niveles de expresión de ARNm de genes de proteínas desacopladoras del músculo esquelético. También se analizaron los efectos fisiológicos y genéticos del ejercicio de natación a baja temperatura sobre los cambios en el metabolismo energético en ratas, tanto a nivel individual como molecular. Los resultados revelaron que el nitrógeno ureico sérico permaneció más estable en ratas nadadoras hipotérmicas en comparación con las ratas del grupo de natación. Además, el estudio observó una regulación positiva inducida de las proteínas desacopladoras en el músculo esquelético de ratas Wistar en respuesta a la estimulación de la temperatura externa, y la expresión de ARNm para las proteínas desacopladoras del músculo esquelético aumentó significativamente a medida que disminuía la temperatura. Además, las nanofibras cortas preparadas también tuvieron un efecto promotor significativo sobre el gen de la proteína de desacoplamiento, COX7A1, al tiempo que suprimieron la expresión del gen lipogénico.

Referred pain is associated with greater odontogenic spontaneous pain and a heightened pain sensitivity in patients with symptomatic irreversible pulpitis.

BACKGROUND: Symptomatic irreversible pulpitis often results in heightened reactions to thermal stimuli such as pain evoked by a cold stimulus, and spontaneous odontogenic pain (unprovoked pain). OBJECTIVE: This study primarily compared the clinical manifestations of odontogenic spontaneous pain and pain provoked by cold stimulus specifically focusing on their sensory discriminative characteristics (intensity, duration and quality) between symptomatic irreversible pulpitis patients with and without referred pain. METHODS: Twenty-three patients with symptomatic irreversible pulpitis with referred pain and 12 patients without referred pain were included in this cross-sectional study. The following outcomes were assessed: odontogenic spontaneous pain and its descriptors; pain evoked by cold stimulus and qualitative sensory testing before and after local anaesthesia; referred pain location; use of analgesic medication; complementary anaesthesia efficacy. T-test, chi-squared and McNemar tests were applied to the data (p < .50). RESULTS: Patients with referred pain presented a greater odontogenic pain intensity (p < .05) when considered the average of the last 24 h. These patients also showed higher pain rating and pain descriptors (p < .05). Intensity and duration of the pain evoked by cold stimulus in the non-affected contralateral tooth at baseline were higher for patients with referred pain (p < .05). CONCLUSION: Symptomatic irreversible pulpitis patients with referred pain present greater odontogenic spontaneous pain and a heightened pain sensitivity. Therefore, patients with referred pain seem more complex from a pain severity perspective, supporting the clinical utility of discriminating symptomatic irreversible pulpitis with and without referred pain.

Effect of pre-cooling on the shelf-life and quality of formosa papaya.

Papaya is a climacteric fruit, rapidly ripening after harvesting due to ethylene production and increased respiratory rate. This swift ripening results in softening of fruit tissues, shortening the fruit shelf life. Pre-cooling serves as an alternative to minimize fruit ripening and post-harvest losses by reducing metabolism. This study aimed to evaluate the effect of pre-cooling on the quality and conservation of Formosa 'Tainung I' papaya. Papayas at maturation stage II were obtained from a commercial orchard with conventional production. The experimental design was a completely randomized 4×6 split-plot scheme, with pre-cooling treatments (Control, without pre-cooling treatment; pre-cooling at 15 °C in a cold chamber; pre-cooling at 7 °C in a cold chamber; and forced-air cooling at 7 °C) in the plot, and days of storage (0, 7, 14, 21, 28, and 35 days) in the subplot. Pre-cooling effectively delayed the ripening and senescence of Formosa papaya, reducing the loss of green color and firmness. Regardless of the treatment used, chilling injury and incidence of fungi from the genus Fusarium and Alternaria limited the shelf life of Formosa 'Tainung I' papaya up to 21 days of storage. Additionally, the appearance of hardened regions in the pulp compromised the sensory quality of the fruits, necessitating further investigation into the causes of this disorder.