A resonant sextuplet of sub-Neptunes transiting the bright star HD 110067.

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

A candidate super-Earth planet orbiting near the snow line of Barnard's star.

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

Reliable and specific detection of Acanthamoeba spp. in dishcloths using quantitative real-time PCR assay.

Acanthamoeba spp., are ubiquitous protist which belongs to Free-Living Amoeba (FLA) group, is considered as causal agent of side-threatening keratitis or fatal encephalitis among other human infections. Besides, this parasite has been reported as host for other microorganisms important to human health such as Campylobacter spp. or Vibrio spp. among others. This role of Acanthamoeba as pathogen and environmental phagocyte has increased the reports confirming its presence in human related environments, acting as a water quality indicator. Considering the tide relationship between water and kitchen environments, and the high prevalence of Acanthamoeba in water sources, the present study aims to establish a quick and accurate protocol based on DNA extraction and a real time qPCR assay to detect Acanthamoeba spp. in dishcloths. The procedure has been validated by processing 17 used dishcloths. Our findings demonstrated the high sensitivity of the qPCR assay used which was capable of detecting up to one Acanthamoeba from an in vitro contaminated dishcloth. The protocol accurately detected 64.7% of positive samples for Acanthamoeba spp, (in 4 samples DNA concentrations corresponded to 1-102 amoebae). Our findings demonstrate the importance of FLA surveillance by efficient and sensitive methods since one amoeba is capable of colonizing human related food environments such as kitchens sinks and could be a potential source of infection.

Seasonal and altitudinal variation in dorsal skin reflectance and thermic rates in a high-altitude montane lizard.

Temperature is one of the most important factors in the life histories of ectotherms, as body temperature has an undeniable effect on growth, activity, and reproduction. Lizards have a wide variety of strategies to acquire and maintain body temperature in an optimal range. The "Thermal Melanism Hypothesis" proposes that individuals with lower skin reflectance can heat up faster as a result of absorbing more solar radiation compared to lighter conspecifics. Therefore, having a darker coloration might be advantageous in cold habitats. Dorsal skin reflectance has been found to change rapidly with body temperature in several lizard species, and it can also vary over longer, seasonal time scales. These variations may be important in thermoregulation, especially in lizards that inhabit areas with a large temperature variation during the year. Here, we study how dorsal reflectance fluctuates with body temperature and varies among seasons. We compared dorsal skin reflectance at three body temperature treatments, and measured thermal rates (i.e., heat and cool rate, thermic lapse, and net heat gain) by elevation (2500-4100 m) and seasons (spring, summer, and autumn) in the mesquite lizard, Sceloporus grammicus. Our results show that lizards were darker at high elevations and during the months with the lowest environmental temperatures. The rate of obtaining and retaining heat also varied during the year and was highest during the reproductive season. Our results indicate that the variation of dorsal skin reflectance and thermal rates follows a complex pattern in lizard populations and is affected by both elevation and season.

Acoustofluidic interferometric device for rapid single-cell physical phenotyping.

High-throughput single-cell analysis based on physical properties (such as morphology or mechanics) is emerging as a powerful tool to inform clinical research, with a great potential for translation towards diagnosis. Here we present a novel microfluidic approach adopting acoustic waves to manipulate and mechanically stimulate single cells, and interferometry to track changes in the morphology and measure size, deformability, and refractive index of non-adherent cells. The method is based on the integration within the acoustofluidic channel of a low-finesse Fabry-Perot resonator, providing very high sensitivity and a speed potentially suitable to obtain the high-throughput necessary to handle the variability stemming from the biological diversity of single cells. The proposed approach is applied to a set of different samples: reference polystyrene beads, algae and yeast. The results demonstrate the capability of the acoustofluidic interferometric device to detect and quantify optomechanical properties of single cells with a throughput suitable to address label-free single-cell clinical analysis.

Phenological variation in parasite load and inflammatory response in a lizard with an asynchronous reproductive cycle.

We present the first study that compares phenological variation in parasite load and inflammatory response in a lizard with asynchronous male and female gonadal cycles. Other studies have used many species with seasonal and synchronous reproductive cycles, in which it is difficult to decouple the effects of internal and external factors that can affect parasite abundance in each sex. Species with asynchronous reproductive cycles provide the opportunity to study the effects of seasonality and reproductive condition separately, but few studies have documented variation in parasite abundance in these species. We made an extensive comparison of parasite load and inflammatory response of the lizard Sceloporus torquatus, a species with asynchronous reproductive cycles, throughout its active period. We hypothesized that the parasite load would be higher in the period of maximum gonadal activity for each sex, negatively related to body condition and inflammatory response. Our results partially support the hypothesis; males had more parasites in summer than in spring and autumn, while females had more parasites in spring and summer than in autumn; however, we do not find a relationship between parasite load, body condition and inflammatory response. Our results indicated that host-parasite interactions are complex and depend upon both environmental and internal factors. Therefore, longer-term studies may provide a more comprehensive picture of host-parasite dynamics in populations of wild lizards.

Uricaemia and associated health determinants in a paediatric population in Mexico.

BACKGROUND AND AIM: Uric acid (UA) is a product of the catabolism of purines, and its increase in blood may be related to the development of cardiometabolic diseases. Whether UA is the result or causal determinant of the appearance of risk factors for cardiometabolic disease is not yet known. UA levels among the young student population in San Luis Potosi have increased in recent years, which may be indicative of a serious future public health concern. Therefore, the objective of this study was to evaluate the association of sociodemographic, lifestyle and cardiometabolic determinants with UA levels in children and adolescents in San Luis Potosí. METHODS AND RESULTS: A total of 730 students (54.1% female and 45.9% male, 6-19 years old) participated in the study. The subjects attended one of five public schools located in San Luis Potosí. Venous blood samples were collected, blood serum was separated by centrifugation, and UA concentrations were measured with an automated analytical platform. UA was associated with most of the independent variables studied. It presented a positive correlation with body mass index (r = 0.363, p < 0.01). Male sex, socioeconomic status, total screen time, exercise, adequate sleep, systolic blood pressure, total cholesterol, and high-density lipoprotein cholesterol explained 23%-39% (p < 0.001) of the variability of plasma concentrations of UA in children and adolescents. CONCLUSION: Early detection of these determinants will prevent future diseases. Moreover, it will help with the implementation of preventive strategies that could improve the health of this population.

In vitro ovicidal activity of Brongniartia montalvoana against small ruminant gastrointestinal nematodes.

Several plants of the Fabaceae family have been assessed regarding their high nutritional value and anthelmintic properties. The ovicidal effect of the hydroalcoholic extract (Bm-HAE) and subfractions from the aerial parts of Brongniartia montalvoana (Fabaceae) against a mixed strain of gastrointestinal nematodes (GIN) (Haemonchus spp., Trichostrongylus spp. and Oesophagostomum spp.) resistant to albendazole sulfoxide, ivermectin and levamisole was evaluated by the egg hatch test (EHT). The Bm-HAE was subjected to liquid-liquid chemical separation with ethyl acetate giving two fractions, an aqueous (Bm-Aq) and an organic (Bm-EtOAct). The purification of the bioactive fraction (Bm-EtOAct) through chromatographic separation resulted in four bioactive subfractions (BmR6, BmR7, BmR8 and BmR10). The treatments were designed as follows: Bm-HAE at 800, 1,500, 3,000 and 6,000 µg/mL, and Bm-Aq, Bm-EtOAct and subfractions (BmR6, BmR7, BmR8 and BmR10) at 100, 200, 400 and 800 µg/mL. Two properly negative controls (distilled water and 2% methanol) and thiabendazole (100 µg/mL) as a positive control were used for each bioassay. The chemical identification of the extract, fractions and subfractions was performed through chromatographic processes like open column chromatography, thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC-PDA). Additionally, the GIN eggs exposed to the bioactive compounds were observed through confocal laser scanning microscopy (CLSM). The Bm-HAE showed 99.5% egg hatching inhibition (EHI) at 6,000 µg/mL with a lethal concentration (LC50) of 1110 µg/mL. The Bm-EtOAc fraction displayed 99.1% EHI at 800 µg/mL with LC50 = 180 µg/mL. The ovicidal activity of the four subfractions was similar at 800 µg/mL: BmR6 (92% EHI); BmR7 (100% EHI); BmR8 (97.8%); and BmR10 (99.1%). The HPLC-PDA analysis of the bioactive subfractions allowed identification of p-coumaric acid, ferulic acid and coumarin derivatives as major compounds. The CLSM analysis allowed observation of morphological alterations in unhatched larvae caused by bioactive compounds present in the Bm-EtOAc and BmR10. In addition, the flavonoids eriodyctiol, luteolin and cynaroside were described for the first time for B. montalvoana.

Differences in moral reasoning among medical graduates, graduates with other degrees, and nonprofessional adults.

BACKGROUND: Reasoning and moral action are necessary to resolve day-to-day moral conflicts, and there are certain professions where a greater moral character is expected, e.g., medicine. Thus, it is desirable that medical students develop skills in this field. Some studies have evaluated the level of moral reasoning among medical students; however, there are no comparative studies involving other types of populations. Therefore, the objective of this study was to compare the moral reasoning among medical graduates with that of a group of young graduates with other degrees and of a group of nonprofessional adults. METHODS: An exploratory cross-sectional study was conducted. Pediatric residents and pediatric subspecialty residents at a pediatric hospital were invited to participate, forming the group of "medical graduates". A group of young people from a social program and students with a master's degree in a science from the same pediatric hospital were also invited to participate, comprising the group of "graduates with other degrees". Finally, a group of beneficiaries of a family clinic was invited to participate, which we categorized as "nonprofessionals". To evaluate the differences in moral reasoning between these 3 groups, we applied the Defining Issues Test (DIT), a moral reasoning questionnaire designed by James Rest using Kohlberg's theory of moral development. RESULTS: The moral reasoning of 237 subjects-88 from the "medical graduates" group, 82 from the "graduates with other degrees" group and 67 from the "nonprofessionals" group- was evaluated. We found differences in the profiles of moral development of the groups. The profile of the "nonprofessionals" showed a very high predominance of subjects at the preconventional level, 70%, but only 4.5% at the postconventional level. Among the "medical graduates", we observed 37.5% at the preconventional level and 34% at the postconventional level (X2 p < 0.001); this group had the highest percentage in this category. This large difference could be because the differences in the ages and socioeducational levels of nonprofessionals are much wider than those among medical graduates. However, significant differences were also found when the profiles of medical graduates were compared with those of graduates with other degrees, since the latter demonstrated 56% at the preconventional level and 18% at the postconventional level (X2 test, p = 0.02). CONCLUSIONS: Significant differences were found in moral reasoning among the groups that we evaluated. Among the group of medical graduates, there was a higher percentage of subjects at the postconventional level than among the group of graduates with other degrees and a much higher percentage than among the group of nonprofessionals. Our conclusions give the first evidence that studying medicine seems to influence the development of moral reasoning in its students. Therefore, we consider it relevant to develop educational strategies where the student is involved in simulated but realistic decision-making situations, where there are moral dilemmas to resolve from their early years of training.

Cyclosporine A plus low-dose steroid treatment in COVID-19 improves clinical outcomes in patients with moderate to severe disease: A pilot study.

BACKGROUND: COVID-19 pandemic causes high global morbidity and mortality and better medical treatments to reduce mortality are needed. OBJECTIVE: To determine the added benefit of cyclosporine A (CsA), to low-dose steroid treatment, in patients with COVID-19. METHODS: Open-label, non randomized pilot study of patients with confirmed infection of SARS-CoV-2 hospitalized from April to May 2020 at a single centre in Puebla, Mexico. Patients were assigned to receive either steroids or CsA plus steroids. Pneumonia severity was assessed by clinical, laboratory, and lung tomography. The death rate was evaluated at 28 days. RESULTS: A total of 209 adult patients were studied, 105 received CsA plus steroids (age 55.3 ± 13.3; 69% men), and 104 steroids alone (age 54.06 ± 13.8; 61% men). All patients received clarithromycin, enoxaparin and methylprednisolone or prednisone up to 10 days. Patient's death was associated with hypertension (RR = 3.5) and diabetes (RR = 2.3). Mortality was 22 and 35% for CsA and control groups (P = 0.02), respectively, for all patients, and 24 and 48.5% for patients with moderate to severe disease (P = 0.001). Higher cumulative clinical improvement was seen for the CsA group (Nelson Aalen curve, P = 0.001, log-rank test) in moderate to severe patients. The Cox proportional hazard analysis showed the highest HR improvement value of 2.15 (1.39-3.34, 95%CI, P = 0.0005) for CsA treatment in moderate to severe patients, and HR = 1.95 (1.35-2.83, 95%CI, P = 0.0003) for all patients. CONCLUSION: CsA used as an adjuvant to steroid treatment for COVID-19 patients showed to improve outcomes and reduce mortality, mainly in those with moderate to severe disease. Further investigation through controlled clinical trials is warranted.

Earthquakes and entropy: Characterization of occurrence of earthquakes in southern Spain and Alboran Sea.

We propose the use of entropy, H, as an indicator of the equilibrium state of a seismically active region (seismic system). The relationship between an increase in H and the occurrence of a great earthquake in a study area can be predicted by acknowledging the irreversible transition of a system. From this point of view, the seismic system evolves from an unstable initial state (due to external stresses) to another, where the stresses have dropped after the earthquake occurred. It is an irreversible transition that entails an increase in entropy. Five seismic episodes were analyzed in the south of the Iberian Peninsula, the Alboran Sea (Mediterranean Sea), and the North of Morocco: two of them of moderate-high magnitude (Al Hoceima, 2004 and 2016) and three of them of moderate-low magnitude (Adra, 1993-1994; Moron, 2007; and Torreperogil, 2012-2013). The results are remarkably in line with the theoretical forecasts; in other words: an earthquake, understood as an irreversible transition, must suppose an increase in entropy.

A Transcriptome Community-and-Module Approach of the Human Mesoconnectome.

Graph analysis allows exploring transcriptome compartments such as communities and modules for brain mesostructures. In this work, we proposed a bottom-up model of a gene regulatory network to brain-wise connectome workflow. We estimated the gene communities across all brain regions from the Allen Brain Atlas transcriptome database. We selected the communities method to yield the highest number of functional mesostructures in the network hierarchy organization, which allowed us to identify specific brain cell functions (e.g., neuroplasticity, axonogenesis and dendritogenesis communities). With these communities, we built brain-wise region modules that represent the connectome. Our findings match with previously described anatomical and functional brain circuits, such the default mode network and the default visual network, supporting the notion that the brain dynamics that carry out low- and higher-order functions originate from the modular composition of a GRN complex network.

A comparative study between real-time PCR and loop-mediated isothermal amplification to detect carbapenemase and/or ESBL genes in Enterobacteriaceae directly from bronchoalveolar lavage fluid samples.

OBJECTIVES: To evaluate and compare the efficacy of real-time PCR (Xpert Carba-R) and loop-mediated isothermal amplification (Eazyplex® SuperBug CRE) for detecting carbapenemase carriage in Enterobacteriaceae directly from bronchoalveolar lavage (BAL). METHODS: Negative BAL samples were spiked with 21 well-characterized carbapenemase-producing Enterobacteriaceae strains to a final concentration of 102-104 cfu/mL. Xpert Carba-R (Cepheid, Sunnyvale, CA, USA), which detects five targets (blaKPC, blaNDM, blaVIM, blaOXA-48 and blaIMP-1), and the Eazyplex® SuperBug CRE system (Amplex-Diagnostics GmbH, Germany), which detects seven genes (blaKPC, blaNDM, blaVIM, blaOXA-48, blaOXA-181, blaCTXM-1 and blaCTXM-9), were evaluated for the detection of these genes directly from BAL samples. RESULTS: Xpert Carba-R showed 100% agreement with carbapenemase characterization by PCR and sequencing for all final bacteria concentrations. Eazyplex® SuperBug CRE showed 100%, 80% and 27% agreement with PCR and sequencing when testing 104, 103 and 102 cfu/mL, respectively. False negative results for Eazyplex® SuperBug CRE matched the highest cycle threshold values for Xpert Carba-R. Hands-on time for both assays was about 15 min, but Eazyplex® SuperBug CRE results were available within 30 min, whereas Xpert Carba-R took around 50 min. CONCLUSIONS: We here describe the successful use of two commercial diagnostic tests, Xpert Carba-R and Eazyplex® SuperBug CRE, to detect bacterial carbapenem resistance genes directly in lower respiratory tract samples. Our results could be used as proof-of-concept data for validation of these tests for this indication.

Effect of cadmium on the viability on monolayer cultures of synoviocytes, chondrocytes, and Hoffa: A preliminary study.

Osteoarthritis (OA) is the gradual loss of articular cartilage and involves several tissues, such as the synovial membrane, meniscus, ligaments, and adipose tissue known as Hoffa fat pad. There are largely unexplored factors that lead to OA development, such as the impact of exposure to heavy metals like cadmium (Cd) on the viability of cells in the knee joint tissue. The objective of this report was to identify the cell type with the highest susceptibility to Cd toxicity with respect to cell viability and death. Our findings showed that a concentration as low as 3 µM cadmium chloride for 12 h affects the viability of synovial cells, and a concentration of 10 µM affects Hoffa cells. Our results suggest that Cd can affect the viability of synovial and chondral cells primarily. In contrast, Hoffa cells were less susceptible, likely because Cd favors the production of pro-inflammatory cytokines before triggering their death as part of its damage mechanism at the articular level.

In vitro ovicidal activity of Baccharis conferta Kunth against Haemonchus contortus.

The indiscriminate use of chemical drugs to deworm livestock tends to trigger an anthelmintic resistance problem. In this context, the use of plant extracts rich in secondary metabolites could be an alternative method for the control of gastrointestinal nematodes. Baccharis conferta Kunth is a native plant species from Mexico that is widely used by several ethnic groups as forage for farm animals and medicinally to treat gastrointestinal diseases such as acute stomach ache, dysentery, diarrhoea, vomiting, indigestion, colic, intestinal spasms, urinary problems, and cramps. The aim of the present study was to isolate and characterise the ovicidal constituents of B. conferta and to determine a possible mode of action against Haemonchus contortus. The ovicidal activity was determined using the egg hatching inhibition test (EHI) to assess the methanol extract obtained from B. conferta foliage. The dry extract was partitioned (water/ethyl acetate) to obtain an ethyl acetate (BcEtOAc-F) and aqueous fraction. BcEtOAc-F showed an ovicidal activity of 72.32% EHI at 1 mg/mL. The chromatographic fractionation of BcEtOAc-F resulted in three active sub-fractions with higher ovicidal activity: BcC1R4 (99.15% EHI at 1.0 mg/mL); BcC1R5 (92.51% EHI at 0.75 mg/mL); and BcC1R8 (96.8% EHI at 3.0 mg/mL). Chemical analysis of the BcC1R4 fraction allowed the identification of the major active compound, isokaempferide (1, 98.06% EHI at 1 mg/mL). While, 4,5-di-O-acid caffeoylquinic (3; 96.8% EHI at 3 mg/mL) and an inactive flavone (vicenin-2, 2) were identified as the main compounds in BcC1R8. Chemical characterisation of the isolated compounds was performed via spectroscopic (NMR) and spectrometric (UPLC-MS) analyses. Additionally, the environmental and confocal scanning microscopy analyses revealed that isokaempferide was able to cross the eggshell layer without breaking it and attach itself to the embryo, causing its death. The flavonol, isokaempferide, and the hydroxycinamic acid, 4,5-di-O-caffeoylquinic, displayed powerful ovicidal effects, proving to be a potential alternative for the development of a phytodrug for the control of haemonchosis.

Deterioration of nutritional status of patients with locally advanced cervical cancer during treatment with concomitant chemoradiotherapy.

BACKGROUND: In Mexico, 80% women with cervical cancer are diagnosed at locally advanced stages and are treated with concomitant chemoradiotherapy. The treatment modality and catabolic state confer a nutritional risk. The present study aimed to thoroughly evaluate the nutritional status and change in body composition of locally advanced cervical cancer (LACC) patients throughout treatment. METHODS: An observational prospective study, carried out at the Mexican National Cancer Institute, included 55 LACC patients. Nutritional status was evaluated before, during and after treatment, using anthropometric, dietary and biochemical measurements. Body composition was analysed using computed tomography images obtained at the time of diagnosis and approximately 4 months after treatment completion. Clinical outcomes were associated with changes in body composition. RESULTS: At the time of diagnosis, no patients were clinically malnourished, although 33.3% presented sarcopenia and most were overweight; by the end of treatment, 69% became clinically malnourished and 58% were sarcopenic. Average weight loss was 7.4 kg (P = 0.001). Adequacy of energy intake was reduced to 54%, obtained predominantly from carbohydrates. By the week 9, 62.8% patients became anemic and 34.5% had low albumin levels. Body composition analysis revealed that patients lost both, muscle and adipose tissues, although 27% patients were muscle depleted by the end of treatment. Patients who lost ≥10% skeletal muscle presented a higher tumour recurrence (hazard ratio = 2.957, P = 0.006) and a tendency towards diminished overall survival (hazard ratio = 2.572, not significant). CONCLUSIONS: The nutritional status of cervical cancer patients deteriorates during treatment with concomitant chemoradiotherapy and, most importantly, muscle loss impacts the clinical outcome of patients.

Experimental Fock-State Superradiance.

Superradiance in an ensemble of atoms leads to the collective enhancement of radiation in a particular mode shared by the atoms in their spontaneous decay from an excited state. The quantum aspects of this phenomenon are highlighted when such collective enhancement is observed in the emission of a single quantum of light. Here we report a further step in exploring experimentally the nonclassical features of superradiance by implementing the process not only with single excitations, but also in a two-excitation state. Particularly, we measure and theoretically model the wave packets corresponding to superradiance in both the single-photon and two-photon regimes. Such progress opens the way to the study and future control of the interaction of nonclassical light modes with collective quantum memories at higher photon numbers.

Expression of proteoglycans in two types of ameloblastoma: novel Immunohistochemical findings.

Alterations in cellular and extracellular matrix components play an important role during tumorigenesis; proteoglycans are included among these components. Ameloblastomas are odontogenic tumors distinguished as invasive and infiltrative neoplasms and are divided into different histological types, the most common of which are the unicystic ameloblastoma and the conventional ameloblastoma. The aim of this study was to identify the presence of two proteoglycans, perlecan and biglycan, in different types of ameloblastoma. Using immunohistochemistry, we determined the presence of both proteins in 28 unicystic ameloblastomas and 23 conventional ameloblastomas. We identified the cytoplasmic and nuclear presence of perlecan and the cytoplasmic presence of biglycan in both types of ameloblastoma. The mean values of immunoexpression were higher in the conventional type compared to the unicystic type. Neither the presence of biglycan in ameloblastomas nor the nuclear presence of perlecan in any odontogenic tumor has previously been reported. The differential immunoexpression of perlecan and biglycan in these types of ameloblastomas suggests their participation in the developmental process of these tumors.

Amino acid profiles of young adults differ by sex, body mass index and insulin resistance.

BACKGROUND AND AIMS: An increase in plasma branched-chain amino acids is associated with a higher risk of developing type 2 diabetes and cardiovascular diseases. However, little is known about the basal plasma amino acid concentrations in young adults. Our aim was to determine the plasma amino acid profiles of young adults and to evaluate how these profiles were modified by sex, body mass index (BMI) and insulin resistance (IR). METHODS AND RESULTS: We performed a transversal study with 608 Mexican young adults aged 19.9 ± 2.4 years who were applicants to the Universidad Autónoma de San Luis Potosí. The subjects underwent a physical examination and provided a clinical history and a blood sample for biochemical, hormonal and amino acid analyses. The women had higher levels of arginine, aspartate and serine and lower levels of α-aminoadipic acid, cysteine, isoleucine, leucine, methionine, proline, tryptophan, tyrosine, urea and valine than the men. The obese subjects had higher levels of alanine, aspartate, cysteine, ornithine, phenylalanine, proline and tyrosine and lower levels of glycine, ornithine and serine than the normal weight subjects. Subjects with IR (defined as HOMA > 2.5) had higher levels of arginine, alanine, aspartate, isoleucine, leucine, phenylalanine, proline, tyrosine, taurine and valine than the subjects without IR. Furthermore, we identified two main groups in the subjects with obesity and/or IR; one group was composed of amino acids that positively correlated with the clinical, biochemical and hormonal parameters, whereas the second group exhibited negative correlations. CONCLUSION: This study demonstrates that young adults with obesity or IR have altered amino acid profiles characterized by an increase in alanine, aspartate, proline and tyrosine and a decrease in glycine.