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1.
Sci Rep ; 14(1): 11314, 2024 05 17.
Article in English | MEDLINE | ID: mdl-38760507

ABSTRACT

This paper focuses on the maximum speed at which biological evolution can occur. I derive inequalities that limit the rate of evolutionary processes driven by natural selection, mutations, or genetic drift. These rate limits link the variability in a population to evolutionary rates. In particular, high variances in the fitness of a population and of a quantitative trait allow for fast changes in the trait's average. In contrast, low variability makes a trait less susceptible to random changes due to genetic drift. The results in this article generalize Fisher's fundamental theorem of natural selection to dynamics that allow for mutations and genetic drift, via trade-off relations that constrain the evolutionary rates of arbitrary traits. The rate limits can be used to probe questions in various evolutionary biology and ecology settings. They apply, for instance, to trait dynamics within or across species or to the evolution of bacteria strains. They apply to any quantitative trait, e.g., from species' weights to the lengths of DNA strands.


Subject(s)
Biological Evolution , Genetic Drift , Selection, Genetic , Mutation , Models, Genetic , Phenotype , Quantitative Trait, Heritable , Evolution, Molecular
2.
Curr Issues Mol Biol ; 45(11): 8716-8732, 2023 Oct 30.
Article in English | MEDLINE | ID: mdl-37998725

ABSTRACT

Type 2 diabetes (T2D) is a chronic systemic disease with a complex etiology, characterized by insulin resistance and mitochondrial dysfunction in various cell tissues. To explore this relationship, we conducted a secondary analysis of complete mtDNA sequences from 1261 T2D patients and 1105 control individuals. Our findings revealed significant associations between certain single-nucleotide polymorphisms (SNPs) and T2D. Notably, the variants m.1438A>G (rs2001030) (controls: 32 [27.6%], T2D: 84 [72.4%]; OR: 2.46; 95%CI: 1.64-3.78; p < 0.001), m.14766C>T (rs193302980) (controls: 498 [36.9%], T2D: 853 [63.1%]; OR: 2.57, 95%CI: 2.18-3.04, p < 0.001), and m.16519T>C (rs3937033) (controls: 363 [43.4%], T2D: 474 [56.6%]; OR: 1.24, 95%CI: 1.05-1.47, p = 0.012) were significantly associated with the likelihood of developing diabetes. The variant m.16189T>C (rs28693675), which has been previously documented in several studies across diverse populations, showed no association with T2D in our analysis (controls: 148 [13.39] T2D: 171 [13.56%]; OR: 1.03; 95%CI: 0.815-1.31; p = 0.83). These results provide evidence suggesting a link between specific mtDNA polymorphisms and T2D, possibly related to association rules, topological patterns, and three-dimensional conformations associated with regions where changes occur, rather than specific point mutations in the sequence.

6.
Phys Rev Lett ; 130(14): 140601, 2023 Apr 07.
Article in English | MEDLINE | ID: mdl-37084448

ABSTRACT

The adiabatic theorem provides sufficient conditions for the time needed to prepare a target ground state. While it is possible to prepare a target state much faster with more general quantum annealing protocols, rigorous results beyond the adiabatic regime are rare. Here, we provide such a result, deriving lower bounds on the time needed to successfully perform quantum annealing. The bounds are asymptotically saturated by three toy models where fast annealing schedules are known: the Roland and Cerf unstructured search model, the Hamming spike problem, and the ferromagnetic p-spin model. Our bounds demonstrate that these schedules have optimal scaling. Our results also show that rapid annealing requires coherent superpositions of energy eigenstates, singling out quantum coherence as a computational resource.

7.
Genes (Basel) ; 13(11)2022 10 27.
Article in English | MEDLINE | ID: mdl-36360199

ABSTRACT

Breast cancer has an important incidence in the worldwide female population. Although alterations in the mitochondrial genome probably play an important role in carcinogenesis, the actual evidence is ambiguous and inconclusive. Our purpose was to explore differences in mitochondrial sequences of cases with breast cancer compared with control samples from different origins. We identified 124 mtDNA sequences associated with breast cancer cases, of which 86 were complete and 38 were partial sequences. Of these 86 complete sequences, 52 belonged to patients with a confirmed diagnosis of breast cancer, and 34 sequences were obtained from healthy mammary tissue of the same patients used as controls. From the mtDNA analysis, two polymorphisms with significant statistical differences were found: m.310del (rs869289246) in 34.6% (27/78) of breast cancer cases and 61.7% (21/34) in the controls; and m.315dup (rs369786048) in 60.2% (47/78) of breast cancer cases and 38.2% (13/34) in the controls. In addition, the variant m.16519T>C (rs3937033) was found in 59% of the control sequences and 52% of the breast cancer sequences with a significant statistical difference. Polymorphic changes are evolutionarily related to the haplogroup H of Indo-European and Euro-Asiatic origins; however, they were found in all non-European breast cancers.


Subject(s)
Breast Neoplasms , Humans , Female , Breast Neoplasms/genetics , DNA, Mitochondrial/genetics , Mitochondria/genetics , Polymorphism, Genetic
8.
Crit Care Res Pract ; 2021: 5866468, 2021.
Article in English | MEDLINE | ID: mdl-34956677

ABSTRACT

INTRODUCTION: Nutritional risk is highly prevalent in patients with COVID-19. Relevant data on nutritional assessment in the critically ill population are scarce. This study was conducted to evaluate the modified Nutrition Risk in the Critically Ill (mNUTRIC)-Score as a mortality risk factor in mechanically ventilated patients with COVID-19. METHODS: We conducted this retrospective observational study in critically ill patients with COVID-19. Patients' characteristics and clinical information were obtained from electronic medical records. The nutritional risk for each patient was assessed at the time of mechanical ventilation using the mNUTRIC-Score. The major outcome was 28-day mortality. RESULTS: Ninety-eight patients were analyzed (mean age, 57.22 ± 13.66 years, 68.4% male); 46.9% of critically ill COVID-19 patients were categorized as being at high nutrition risk (mNUTRIC-Score of ≥5). A multivariate logistic regression model indicated that high nutritional risk has higher 28-day hospital mortality (OR = 4.206, 95% CI: 1.147-15.425, p=0.030). A multivariate Cox regression analysis showed that high-risk mNUTRIC-Score had a significantly increased full-length mortality risk during hospitalization (OR = 1.991, 95% CI: 1.219-3.252, p=0.006). CONCLUSION: The mNUTRIC-Score is an independent mortality risk factor during hospitalization in critically ill COVID-19 patients.

9.
Entropy (Basel) ; 23(11)2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34828225

ABSTRACT

We formulate limits to perception under continuous quantum measurements by comparing the quantum states assigned by agents that have partial access to measurement outcomes. To this end, we provide bounds on the trace distance and the relative entropy between the assigned state and the actual state of the system. These bounds are expressed solely in terms of the purity and von Neumann entropy of the state assigned by the agent, and are shown to characterize how an agent's perception of the system is altered by access to additional information. We apply our results to Gaussian states and to the dynamics of a system embedded in an environment illustrated on a quantum Ising chain.

10.
Phys Rev Lett ; 127(2): 028902, 2021 Jul 09.
Article in English | MEDLINE | ID: mdl-34296920

ABSTRACT

We acknowledge that a derivation reported in Phys. Rev. Lett. 125, 040601 (2020)PRLTAO0031-900710.1103/PhysRevLett.125.040601 is incorrect as pointed out by Cusumano and Rudnicki. We respond by giving a correct proof of the claim "fluctuations in the free energy operator upper bound the charging power of a quantum battery" that we made in the Letter.

11.
Rev. Soc. Odontol. La Plata ; 31(60): 23-26, jul. 2021. ilus
Article in Spanish | LILACS | ID: biblio-1284468

ABSTRACT

Las neoplasias malignas de la cavidad oral en gran medida (90%) consisten en carcinoma de células escamosas que surgen de la mucosa de revestimiento. El 10% restantes de neoplasias malignas orales de un grupo heterogéneo de tumores de diferente etiología. Presentamos dos casos de patología oncohematológica: Mieloma Múltiple (AU)


Malignant neoplasms of the oral cavity largely (90%) consist of squamous cell carcinoma arising from the lining mucosa. e remaining 10% of oral malignancies from a heterogeneous group of tumors of different etiology. We present two cases of oncohematological pathology: Multiple Myeloma (AU)


Subject(s)
Humans , Male , Middle Aged , Plasmacytoma/diagnosis , Plasmacytoma/pathology , Plasmacytoma/diagnostic imaging , Mouth Neoplasms/diagnosis , Radiotherapy , Biopsy/methods , Tomography, X-Ray Computed , Oral Surgical Procedures/methods , Diphosphonates/therapeutic use , Maxillary Sinus/surgery , Multiple Myeloma
12.
Phys Rev Lett ; 125(4): 040601, 2020 Jul 24.
Article in English | MEDLINE | ID: mdl-32794781

ABSTRACT

We study the connection between the charging power of quantum batteries and the fluctuations of the extractable work. We prove that in order to have a nonzero rate of change of the extractable work, the state ρ_{W} of the battery cannot be an eigenstate of a "free energy operator," defined by F≡H_{W}+ß^{-1}log(ρ_{W}), where H_{W} is the Hamiltonian of the battery and ß is the inverse temperature of a reference thermal bath with respect to which the extractable work is calculated. We do so by proving that fluctuations in the free energy operator upper bound the charging power of a quantum battery. Our findings also suggest that quantum coherence in the battery enhances the charging process, which we illustrate on a toy model of a heat engine.

14.
Phys Rev Lett ; 124(11): 110605, 2020 Mar 20.
Article in English | MEDLINE | ID: mdl-32242711

ABSTRACT

We give rigorous analytical results on the temporal behavior of two-point correlation functions-also known as dynamical response functions or Green's functions-in closed many-body quantum systems. We show that in a large class of translation-invariant models the correlation functions factorize at late times ⟨A(t)B⟩_{ß}→⟨A⟩_{ß}⟨B⟩_{ß}, thus proving that dissipation emerges out of the unitary dynamics of the system. We also show that for systems with a generic spectrum the fluctuations around this late-time value are bounded by the purity of the thermal ensemble, which generally decays exponentially with system size. For autocorrelation functions we provide an upper bound on the timescale at which they reach the factorized late time value. Remarkably, this bound is only a function of local expectation values and does not increase with system size. We give numerical examples that show that this bound is a good estimate in nonintegrable models, and argue that the timescale that appears can be understood in terms of an emergent fluctuation-dissipation theorem. Our study extends to further classes of two point functions such as the symmetrized ones and the Kubo function that appears in linear response theory, for which we give analogous results.

15.
Oxid Med Cell Longev ; 2020: 3096470, 2020.
Article in English | MEDLINE | ID: mdl-32256949

ABSTRACT

Diabetes mellitus (DM) is a progressive disease induced by a sustained state of chronic hyperglycemia that can lead to several complications targeting highly metabolic cells. Diabetic retinopathy (DR) is a multifactorial microvascular complication of DM, with high prevalence, which can ultimately lead to visual impairment. The genesis of DR involves a complex variety of pathways such as oxidative stress, inflammation, apoptosis, neurodegeneration, angiogenesis, lipid peroxidation, and endoplasmic reticulum (ER) stress, each possessing potential therapeutic biomarkers. A specific treatment has yet to be developed for early stages of DR since no management is given other than glycemic control until the proliferative stage develops, offering a poor visual prognosis to the patient. In this narrative review article, we evaluate different dietary regimens, such as the Mediterranean diet, Dietary Pattern to Stop Hypertension (DASH) and their functional foods, and low-calorie diets (LCDs). Nutraceuticals have also been assessed in DR on account of their antioxidant, anti-inflammatory, and antiangiogenic properties, which may have an important impact on the physiopathology of DR. These nutraceuticals have shown to lower reactive oxygen species (ROS), important inflammatory factors, cytokines, and endothelial damage biomarkers either as monotherapies or combined therapies or concomitantly with established diabetes management or nonconventional adjuvant drugs like topical nonsteroidal anti-inflammatory drugs (NSAIDs).


Subject(s)
Chemotherapy, Adjuvant/methods , Diabetic Retinopathy/diet therapy , Inflammation/metabolism , Oxidative Stress/physiology , Disease Progression , Humans
16.
Phys Rev Lett ; 123(9): 090403, 2019 Aug 30.
Article in English | MEDLINE | ID: mdl-31524475

ABSTRACT

Spontaneous symmetry breaking (SSB) is responsible for structure formation in scenarios ranging from condensed matter to cosmology. SSB is broadly understood in terms of perturbations to the Hamiltonian governing the dynamics or to the state of the system. We study SSB due to quantum monitoring of a system via continuous quantum measurements. The acquisition of information during the measurement process induces a measurement backaction that seeds SSB. In this setting, by monitoring different observables, an observer can tailor the topology of the vacuum manifold, the pattern of symmetry breaking, and the nature of the resulting domains and topological defects.

17.
Phys Rev Lett ; 122(1): 014103, 2019 Jan 11.
Article in English | MEDLINE | ID: mdl-31012673

ABSTRACT

We study the ultimate limits to the decoherence rate associated with dephasing processes. Fluctuating chaotic quantum systems are shown to exhibit extreme decoherence, with a rate that scales exponentially with the particle number, thus exceeding the polynomial dependence of systems with fluctuating k-body interactions. Our findings suggest the use of quantum chaotic systems as a natural test bed for spontaneous wave function collapse models. We further discuss the implications on the decoherence of AdS/CFT black holes resulting from the unitarity loss associated with energy dephasing.

18.
J Circ Biomark ; 7: 1849454418804099, 2018.
Article in English | MEDLINE | ID: mdl-30302131

ABSTRACT

Oxidative stress induces nerve damage in type 2 diabetes mellitus and leads to diabetic polyneuropathy (DPN) and can affect the DNA and antioxidant status. Statins have pleiotropic, protective effects on the peripheral nerves of patients with diabetes. The aim of this study was to determine the effects of ezetimibe/simvastatin and rosuvastatin on DNA damage in patients with DPN. This randomized, double-blind, placebo-controlled, clinical trial comprised outpatients from Guadalajara, Mexico. The inclusion criteria were either gender, age 35-80 years, type 2 diabetes, glycated hemoglobin ≤10%, diabetic polyneuropathy stage 1/2, and signed informed consent. Patients who were taking antioxidant therapy or statins, had hypersensitivity to drugs, experienced organ failure, were pregnant or breastfeeding, or had other types of neuropathy were excluded. We assigned patients to placebo, ezetimibe/simvastatin 10/20 mg, or rosuvastatin 20 mg, and the primary outcomes were 8-hydroxy-2'-deoxyguanosine (8-OHdG) for DNA damage, 8-oxoguanine-DNA-N-glycosilase (hOGG1) for DNA repair, and superoxide dismutase (SOD). Seventy-four patients were recruited. Nine patients were included as negative controls. There were no differences in 8-OHdG between the healthy subjects (4.68 [3.53-6.38] ng/mL) and the DPN patients (4.51 [1.22-9.84] ng/mL), whereas the hOGG1 level was 0.39 (0.37-0.42) ng/mL in the healthy subjects and 0.41 (0.38-0.54) ng/mL in patients with DPN at baseline (p = 0.01). SOD decreased significantly in patients with DPN (5.35 [0.01-17.90] U/mL) compared with the healthy subjects (9.81 [8.66-12.61] U/mL) at baseline (p < 0.001). No significant changes in DNA biomarkers were observed in any group between baseline and final levels. We noted a rise in hOGG1 in patients with DPN, without modifications after treatment. There was a slight, albeit insignificant, increase in SOD in patients who were on statins.

19.
Food Funct ; 7(9): 3686-93, 2016 Sep 14.
Article in English | MEDLINE | ID: mdl-27491778

ABSTRACT

In heart failure patients the consumption of (-)-epicatechin ((-)-Epi)-rich cocoa can restore skeletal muscle (SkM) mitochondrial structure and decrease biomarkers of oxidative stress. However, nothing is known about its effects on exercise capacity and underlying mechanisms in normal, sedentary subjects. Twenty normal, sedentary subjects (∼50 years old) were randomized to placebo or dark chocolate (DC) groups and consumed 20 g of the products for 3 months. Subjects underwent before and after treatment, bicycle ergometry to assess VO2 max and work, SkM biopsy to assess changes in mitochondrial density, function and oxidative stress and blood sampling to assess metabolic endpoints. Seventeen subjects completed the trial. In the DC group (n = 9), VO2 max increased (17% increase, p = 0.056) as well as maximum work (watts) achieved (p = 0.026) with no changes with placebo (n = 8). The DC group evidenced increases in HDL levels (p = 0.005) and decreased triglycerides (p = 0.07). With DC, SkM evidenced significant increases in protein levels for LKB1, AMPK and PGC1α and in their active forms (phosphorylated AMPK and LKB1) as well as in citrate synthase activity while no changes were observed in mitochondrial density. With DC, significant increases in SkM reduced glutathione levels and decreases in protein carbonylation were observed. Improvements in maximum work achieved and VO2 max may be due to DC activation of upstream control systems and enhancement of SkM mitochondria efficiency. Larger clinical studies are warranted to confirm these observations.


Subject(s)
Cacao/metabolism , Chocolate/analysis , Exercise , Muscle, Skeletal/metabolism , Adult , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Sedentary Behavior , Triglycerides/metabolism
20.
J Diabetes Res ; 2016: 3425617, 2016.
Article in English | MEDLINE | ID: mdl-28058263

ABSTRACT

Diabetic polyneuropathy (DPN) is defined as peripheral nerve dysfunction. There are three main alterations involved in the pathologic changes of DPN: inflammation, oxidative stress, and mitochondrial dysfunction. Inflammation induces activation of nuclear factor kappa B, activator protein 1, and mitogen-activated protein kinases. Oxidative stress induced by hyperglycemia is mediated by several identified pathways: polyol, hexosamine, protein kinase C, advanced glycosylation end-products, and glycolysis. In addition, mitochondrial dysfunction accounts for most of the production of reactive oxygen and nitrosative species. These free radicals cause lipid peroxidation, protein modification, and nucleic acid damage, to finally induce axonal degeneration and segmental demyelination. The prevalence of DPN ranges from 2.4% to 78.8% worldwide, depending on the diagnostic method and the population assessed (hospital-based or outpatients). Risk factors include age, male gender, duration of diabetes, uncontrolled glycaemia, height, overweight and obesity, and insulin treatment. Several diagnostic methods have been developed, and composite scores combined with nerve conduction studies are the most reliable to identify early DPN. Treatment should be directed to improve etiologic factors besides reducing symptoms; several approaches have been evaluated to reduce neuropathic impairments and improve nerve conduction, such as oral antidiabetics, statins, and antioxidants (alpha-lipoic acid, ubiquinone, and flavonoids).


Subject(s)
Diabetes Mellitus, Type 2/metabolism , Diabetic Neuropathies/metabolism , Mitochondria/metabolism , Oxidative Stress/drug effects , Animals , Antioxidants/metabolism , Diabetes Mellitus, Type 2/epidemiology , Diabetic Neuropathies/epidemiology , Female , Free Radicals/metabolism , Humans , Inflammation , Insulin/metabolism , Lipid Peroxidation , Male , Prevalence , Reactive Oxygen Species/metabolism , Risk Factors , Treatment Outcome
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