Perturbations in mitochondrial metabolism associated with defective cardiolipin biosynthesis: An in-organello real-time NMR study.

Mitochondria are central to cellular metabolism; hence, their dysfunction contributes to a wide array of human diseases including cancer, cardiopathy, neurodegeneration, and heritable pathologies such as Barth syndrome. Cardiolipin, the signature phospholipid of the mitochondrion promotes proper cristae morphology, bioenergetic functions, and directly affects metabolic reactions carried out in mitochondrial membranes. To match tissue-specific metabolic demands, cardiolipin typically undergoes an acyl tail remodeling process with the final step carried out by the phospholipid-lysophospholipid transacylase tafazzin. Mutations in the tafazzin gene are the primary cause of Barth syndrome. Here, we investigated how defects in cardiolipin biosynthesis and remodeling impact metabolic flux through the tricarboxylic acid cycle and associated pathways in yeast. Nuclear magnetic resonance was used to monitor in real-time the metabolic fate of 13 C 3 -pyruvate in isolated mitochondria from three isogenic yeast strains. We compared mitochondria from a wild-type strain to mitochondria from a Δ taz1 strain that lacks tafazzin and contains lower amounts of unremodeled cardiolipin, and mitochondria from a Δ crd1 strain that lacks cardiolipin synthase and cannot synthesize cardiolipin. We found that the 13 C-label from the pyruvate substrate was distributed through about twelve metabolites. Several of the identified metabolites were specific to yeast pathways, including branched chain amino acids and fusel alcohol synthesis. Most metabolites showed similar kinetics amongst the different strains but mevalonate and α-ketoglutarate, as well as the NAD+/NADH couple measured in separate nuclear magnetic resonance experiments, showed pronounced differences. Taken together, the results show that cardiolipin remodeling influences pyruvate metabolism, tricarboxylic acid cycle flux, and the levels of mitochondrial nucleotides.

Formerly degenerate seventh zinc finger domain from transcription factor ZNF711 rehabilitated by experimental NMR structure.

Domain Z7 of nuclear transcription factor ZNF711 has the consensus last metal-ligand H23 found in odd-numbered zinc-fingers of this protein replaced by a phenylalanine. Ever since the discovery of ZNF711 it has been thought that Z7 is probably non-functional because of the H23F substitution. The presence of H26 three positions downstream prompted us to examine if this histidine could substitute as the last metal ligand. The Z7 domain adopts a stable tertiary structure upon metal binding. The NMR structure of Zn2+-bound Z7 shows the classical ßßα-fold of CCHH zinc fingers. Mutagenesis and pH titration experiments indicate that H26 is not involved in metal binding and that Z7 has a tridentate metal-binding site comprised of only residues C3, C6, and H19. By contrast, an F23H mutation that introduces a histidine in the consensus position forms a tetradentate ligand. The structure of the WT Z7 is stable causing restricted ring-flipping of phenyalanines 10 and 23. Dynamics are increased with either the H26A or F23H substitutions and aromatic ring rotation is no longer hindered in the two mutants. The mutations have only small effects on the Kd values for Zn2+ and Co2+ and retain the high thermal stability of the WT domain above 80 °C. Like two previously reported designed zinc fingers with the last ligand replaced by water, the WT Z7 domain is catalytically active, hydrolyzing 4-nitophenyl acetate. We discuss the implications of naturally occurring tridentate zinc fingers for cancer mutations and drug targeting of notoriously undruggable transcription factors. Our findings that Z7 can fold with only a subset of three metal ligands suggests the recent view that most everything about protein structure can be predicted through homology modeling might be premature for at least the resilient and versatile zinc-finger motif.

NMR structure verifies the eponymous zinc finger domain of transcription factor ZNF750.

ZNF750 is a nuclear transcription factor that activates skin differentiation and has tumor suppressor roles in several cancers. Unusually, ZNF750 has only a single zinc-finger (ZNF) domain, Z*, with an amino acid sequence that differs markedly from the CCHH family consensus. Because of its sequence differences Z* is classified as degenerate, presumed to have lost the ability to bind the zinc ion required for folding. AlphaFold predicts an irregular structure for Z* with low confidence. Low confidence predictions are often inferred to be intrinsically disordered regions of proteins, which would be the case if Z* did not bind Zn2+. We use NMR and CD spectroscopy to show that a 25-51 segment of ZNF750 corresponding to the Z* domain folds into a well-defined antiparallel ßßα tertiary structure with a pM dissociation constant for Zn2+ and a thermal stability >80 °C. Of three alternative Zn2+ ligand sets, Z* uses a CCHC rather than the expected CCHH ligating motif. The switch in the last ligand maintains the folding topology and hydrophobic core of the classical ZNF motif. CCHC ZNFs are typically associated with protein-protein interactions, raising the possibility that ZNF750 interacts with DNA through other proteins rather than directly. The structure of Z* provides context for understanding the function of the domain and its cancer-associated mutations. We expect other ZNFs currently classified as degenerate could be CCHC-type structures like Z*.

Changing face of socio-economic vulnerability and COVID-19: An analysis of country wealth during the first two years of the pandemic.

There are numerous academic studies on the relationship between population wealth and the incidence of COVID-19. However, research developed shows contradictory results on their relationship. In accordance with this question, this work pursues two objectives: on the one hand, to check whether wealth and disease incidence have a unidirectional and stable relationship. And on the other hand, to find out if the country's statistical production capacity is masking the real incidence of the COVID-19 pandemic. In order to achieve this objective, an ecological study has been designed at international level with the countries established as study units. The analytical strategy utilized involves the consecutive application of cross-sectional analysis, specifically employing multivariate linear regression daily throughout the first two years of the pandemic (from 03/14/2020 to 03/28/2022). The application of multiple cross-sectional analysis has shown that country wealth has a dynamic relationship with the incidence of COVID-19. Initially, it appears as a risk factor and, in the long term, as a protective element. In turn, statistical capacity appears as an explanatory variable for the number of published COVID-19 cases and deaths. Therefore, the inadequate statistical production capacity of low income countries may be masking the real incidence of the disease.

WITHDRAWN: NMR structure verifies the eponymous zinc finger domain of transcription factor ZNF750.

This article was initially published in the Journal of Structural Biology, instead of the Journal of Structural Biology: X, due to a publisher error. We regret the inconvenience. The link to the article published in Journal of Structural Biology: X is presented below: https://www.sciencedirect.com/science/article/pii/S2590152423000090. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal.

Business cycle clocks: Time to get circular.

Assessing the momentum of the business cycle is of utmost importance for policymakers and private agents. In this respect, the use of business cycle clocks has gained prominence among national and international institutions to depict the current stage of the business cycle. Drawing on circular statistics, we propose a novel approach to business cycle clocks in a data-rich environment. The method is applied to the main euro area countries resorting to a large data set covering the last three decades. We document the usefulness of the circular business cycle clock to capture the business cycle stage, including peaks and troughs, with the findings being supported by the cross-country evidence.

Multivariate Analysis of Risk Factors of the COVID-19 Pandemic in the Community of Madrid, Spain.

It has been more than one year since Chinese authorities identified a deadly new strain of coronavirus, SARS-CoV-2. Since then, the scientific work regarding the transmission risk factors of COVID-19 has been intense. The relationship between COVID-19 and environmental conditions is becoming an increasingly popular research topic. Based on the findings of the early research, we focused on the community of Madrid, Spain, which is one of the world's most significant pandemic hotspots. We employed different multivariate statistical analyses, including principal component analysis, analysis of variance, clustering, and linear regression models. Principal component analysis was employed in order to reduce the number of risk factors down to three new components that explained 71% of the original variance. Cluster analysis was used to delimit the territory of Madrid according to these new risk components. An ANOVA test revealed different incidence rates between the territories delimited by the previously identified components. Finally, a set of linear models was applied to demonstrate how environmental factors present a greater influence on COVID-19 infections than socioeconomic dimensions. This type of local research provides valuable information that could help societies become more resilient in the face of future pandemics.

The Daily Economic Indicator: tracking economic activity daily during the lockdown.

The SARS-CoV-2 outbreak made clear the urgent need to depart from traditional statistics, typically released with a lag and available at a relatively low frequency. This led to unparalleled efforts to put forward high-frequency indicators to track economic developments timely. By resorting to non-traditional data sources, we propose a novel daily economic indicator to track economic activity in Portugal. It corresponds to the latent variable of a set of daily series within a factor model framework. We find a sudden and sharp drop in economic activity in mid-March 2020, when the lockdown of several activities was declared due to the COVID-19 pandemic. Since in this approach we address the complexities of high-frequency data without further smoothing, we are able to identify sudden changes of economic activity in a timely and daily manner in contrast with other approaches.

Diferencias de género en el consumo diario de tabaco e intensivo de alcohol en adolescentes latinoamericanos en tres áreas españolas (Andalucía, Madrid y País Vasco) / Gender differences to daily smoking and binge drinking in the Latinoamerican Adolescents in three Spanish areas

El consumo diario de tabaco e intensivo de alcohol en la adolescencia puede configurarse como hábitos persistentes para la vida adulta. En este trabajo se pretende explorar las diferencias entre chicos y chicas adolescentes de origen latino con consumos intensivos de tabaco y alcohol, dado que son escasos los trabajos en España que introducen la variable cultural o étnica. Se trata de un estudio trasversal mediante encuesta escolar, a 1126 adolescentes de origen latino, escolarizados en la Educación Secundaria en tres zonas españolas, de 12 a 19 años. Entre los resultados destacamos que el 9,4% de los chicos y el 5,6% de las chicas latinas fumaban diariamente y el 24,2% de los chicos y el 19% de las chicas bebió cinco o más bebidas alcohólicas en el último evento. Fumar diariamente se asoció con ser chico, fumar el padre, fumar la pareja, actuando como factor de protección hacer deporte. Ser chico, emborracharse y haber ido de botellón aumenta la probabilidad de consumir alcohol de forma intensiva. Para concluir destacamos que existen diferencias de género en los consumos de tabaco y alcohol en el tipo de consumo intensivo pero no se aprecia cuando se trata del uso de estas sustancias. Se plantea la necesidad de tener en cuenta la variable de origen cultural en las intervenciones educativas sociosanitarias (AU)

The daily smoking and binge drinking in adolescence may produce persistent habit for adulthood. The objective of this research is to explore the differences between Latinoamerican girls and boys adolescents in the tobacco and alcohol consumes. The researches with cultural variable are scant in Spain. This study is transversal via a school survey comprising 1126 Latinoamerican adolescents, in Secondary Education in three areas and ranging from 12 to 19 years of age. The results are the 9,4% of the boys and the 5,6% of the girls smoke daily, and the 24,2% of the boys and the 19% of the girls for binge drinking the last event. The probability of daily smoking was associated to be a boy, to have a smoking father, to have a smoking couple and as protection factor was to do sport. So, to be a boy, to get drunk and have gone to Botellon increase the probability to binge drinking. The most important conclusion is that there were differences of gender in tobacco and alcohol abuse but not in the use. It is necessary to introduce the cultural variable in educative, health and social prevention (AU)

Evaluation of lateral spinal hemisection as a preclinical model of spinal cord injury pain.

Operant escape from nociceptive thermal stimulation of 13 Long-Evans rats was compared before and after lateral spinal hemisection, to determine whether this lesion configuration provides an appropriate preclinical model of the hyperalgesia that can be associated with human spinal cord injury. Escape from 44 °C and from 47 °C stimulation was not affected following sham spinal surgery but was significantly reduced over 20 weeks of postoperative testing following lateral spinal hemisection. This result is opposite to previous reports of enhanced reflex withdrawal in response to thermal stimulation of rats following lateral spinal hemisection. In addition, the latency of reflexive lick/guard responses to 44 °C was increased and the duration of lick/guard responding was decreased in the present study (hyporeflexia). Thus, previous assessments of simple withdrawal reflexes have described a hyperreflexia following lateral spinal hemisection that was not replicated by lick/guard testing, and postoperative escape responding revealed hypoalgesia rather than the increased pain sensitivity expected in a model of chronic pain.

Sex differences in effects of excitotoxic spinal injury on below-level pain sensitivity.

Effects of excitotoxic injury to the thoracic gray matter on sensitivity to below-level nociceptive stimulation were evaluated for female and male Long-Evans rats. Operant escape and lick/guard (L/G) reflex responses to thermal stimulation were evaluated before and for 13-15 weeks after: 1) injections of quisqualic acid (QUIS) into the thoracic gray matter (T8-9), 2) laminectomy and spinal exposure and penetration without injection (sham) or 3) no surgical procedure (control). L/G responding to heat stimulation (44 °C) was unaffected for females and males following thoracic QUIS injections. Similarly, male escape performance was not significantly altered for 44 °C or 10 °C stimulation after QUIS injections or sham surgery. However, escape testing following QUIS and sham injections revealed increased heat sensitivity (44 °C) and decreased cold sensitivity (10 °C) for females. This selective effect is indicative of altered sympathetic activation by the thoracic injections. The effect of sham surgery suggests that female rats are vulnerable to ischemic injury during exposure and manipulation of the spinal cord. Escape from nociceptive heat and cold sensitivity of control males and females was unchanged over 13-15 weeks of testing.

Sex differences in thermal pain sensitivity and sympathetic reactivity for two strains of rat.

UNLABELLED: Human females are more sensitive than males to brief nociceptive stimuli such as heat and cold. However, a more pronounced peripheral vasoconstriction by females than by males during prolonged nociceptive stimulation predicts that females would be more sensitive to prolonged cold but not heat stimulation. We tested this possibility with reflex (lick/guard) and operant escape and preference tests of sensitivity to prolonged stimulation of Long-Evans and Sprague-Dawley rats. Escape responses to cold stimulation revealed a greater sensitivity of females. In contrast, males were more sensitive to nociceptive heat stimulation. An operant preference test of relative sensitivity to cold or heat stimulation confirmed these results. Cold was more aversive than heat for females, but heat was more aversive than cold for males. Recordings of skin temperature during nociceptive heat stimulation were consistent with the results of operant testing. A reduction in skin temperature (peripheral vasoconstriction) during nociceptive stimulation should increase cold sensitivity as observed for females relative to males. Lick/guard testing did not confirm the results of operant testing. Lick/guard (L/G) responding to nociceptive heat stimulation was greater for females than for males. Female escape responses to heat were more variable than males, but L/G responding of males to the same stimulus was more variable than for females. PERSPECTIVE: A variety of chronic pain conditions are more prevalent for females, and psychological stress (with attendant sympathetic activation) is implicated in development and maintenance of these conditions. Therefore, understanding relationships between gender differences in pain sensitivity and sympathetic activation could shed light on mechanisms for some varieties of chronic pain.

Treatment of subacute low back pain with a novel device for continuous passive motion of the spine: a report of three cases.

Patients experiencing subacute low back pain (LBP) represent a challenge for the physical therapist. There have been few studies on the use of continuous passive motion of the lumbar spine for the treatment of LBP. Three patients with symptoms of subacute LBP without radiculopathy were treated using a novel device for continuous passive motion of the lumbar spine. The protocol consisted of 12 sessions of lumbar continuous passive motion at 30 minutes per session two to three times per week for 4 to 5 weeks. Outcomes were assessed at baseline and after 12 sessions at 4 to 5 weeks by Oswestry score and active range of motion measurements by a blinded investigator. Clinically significant improvements in Oswestry score and consistent improvements in range were observed. A supervised protocol using a commercial device can benefit some patients with subacute LBP if supervised by a knowledgeable practitioner.

Bilateral chronic constriction of the sciatic nerve: a model of long-term cold hyperalgesia.

UNLABELLED: Effects of chronic constriction injury (CCI) and sham surgery of both sciatic nerves were evaluated for reflex lick/guard (L/G) and operant escape responses to thermal stimulation of rats. Experiment 1 compared L/G and escape responses to 0.3 degrees C, 43 degrees C, and 47 degrees C stimulation during a period of 60 days after CCI. Experiment 2 evaluated escape from 44 degrees C, 47 degrees C, and 10 degrees C for 100 days after CCI. The rats escaped from heat or cold stimulation of the paws in a dark compartment by climbing on a thermally neutral platform in a brightly lit compartment. For reflex testing, a single compartment provided no escape option. There was no significant effect of bilateral CCI on reflex or escape responses to nociceptive heat. However, there were long-term increases in the duration of L/G responding during trials of 0.3 degrees C stimulation and in the duration of escape responding to 10 degrees C. Hyperalgesia for cold was confirmed by a preference test, with a 2-compartment shuttle box with one floor heated (45 degrees C) and the other floor cooled (10 degrees C). Occupancy of the heated compartment was significantly increased by CCI (indicating a relative aversion for cold). PERSPECTIVE: For preclinical testing of treatments for allodynia/hyperalgesia after nerve injury, it is crucial to use methods of testing that are sensitive to effects on nociception throughout the neuraxis. Operant escape testing satisfies this criterion and is sensitive to bilateral CCI of rats, which avoids asymmetric postural/motor influences of unilateral CCI.

Low dose systemic morphine attenuates operant escape but facilitates innate reflex responses to thermal stimulation.

Effects of systemic morphine on operant escape responses of rats to thermal stimulation were compared directly with effects on innate licking and guarding responses. For these independent tests, thermal stimulation was delivered via the floor of testing chambers with or without platforms that provided an escape option. The principal findings were (1) administration of 0.5 to 1.5 mg/kg morphine attenuated escape from nociceptive heat and (2) in distinct contrast, licking and guarding responses to heat were enhanced by these doses. When escape responding was calculated as time on the heated plate without licking or guarding, sensitivity to morphine was greater for 44 degrees C than for 47 degrees C or 50 degrees C. Also, escape responses to cold (0 degrees C or 10 degrees C) were unaffected by 1.5 mg/kg morphine. The preferential reduction of heat nociception by morphine was demonstrated also by an operant preference task that gave the animals the option of standing on a cold (10 degrees C) or a hot (45 degrees C) surface. Administration of 0.5 mg/kg morphine increased occupancy of the hot surface. Platform time during operant tests was low and variable for warm stimulation (36 degrees C) and was significantly increased by each level of heat, showing that platform occupancy represented escape from nociception rather than avoidance responses. A lack of significant effects of 1.5 mg/kg morphine on operant performance during cold or warm stimulation controls for effects of systemic morphine other than antinociception.