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1.
Reprod Biomed Online ; 49(3): 104076, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38959531

RESUMO

RESEARCH QUESTION: Is low serum 25-hydroxyvitamin D (25(OH)D) associated with an increased risk of miscarriage in women who presented with threatened miscarriage to the Early Pregnancy Assessment Clinic (EPAC)? DESIGN: This was a secondary retrospective analysis using archived serum samples from a randomized, double-blind, placebo-controlled trial. Stored serum samples from 371 women presenting to the EPAC with threatened miscarriage during the first trimester were assayed for 25(OH)D by liquid chromatography-mass spectrometry. RESULTS: The overall miscarriage rate was 45/371 (12.1%) in the whole cohort. After grouping vitamin D insufficiency and vitamin D sufficiency together into a 'non-deficient' group and excluding participants who underwent termination of pregnancy, there was no difference in the miscarriage rate between those who were vitamin D deficient compared with those who were not (25/205, 12.2% versus 20/157, 12.7%, P= 0.877, odds ratio 0.951, 95% CI 0.507-1.784). When analysed according to the number of gestational weeks, the miscarriage rate was significantly higher in the vitamin D non-deficient group than the vitamin D-deficient group in women who presented at 6 gestational weeks or earlier (13/33 [39.4%] versus 10/58 [17.2%], P= 0.019), but there were no statistically significant differences between the two groups presenting at later gestations. There was no difference in the vitamin D level in women who had a miscarriage compared with those who had a live birth (48 [37-57] versus 47 [37-58] nmol/l, P= 0.725 median [25th-75th percentile]). CONCLUSIONS: A low serum vitamin D concentration was not associated with an increased risk of miscarriage in women with threatened miscarriage presenting to the EPAC.

2.
Nat Neurosci ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956164

RESUMO

Here we conducted wireless electrophysiological recording of hippocampal neurons from Egyptian fruit bats in the presence of human experimenters. In flying bats, many neurons modulated their activity depending on the identity of the human at the landing target. In stationary bats, many neurons carried significant spatial information about the position and identity of humans traversing the environment. Our results reveal that hippocampal activity is robustly modulated by the presence, movement and identity of human experimenters.

3.
Am J Surg ; : 115834, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38991911

RESUMO

BACKGROUND: Across surgery, marginalized individuals experience worse postoperative outcomes. These disparities stem from the interplay between multiple factors. METHODS: We introduced a novel framework to assess the role of barriers to access and bias in surgical complications (the uChicago Health Inequity Classification System, CHI-CS) in the setting of morbidity and mortality conference and assessed impact through pre and post implementation surveys. RESULTS: Access and bias were related to surgical complications in 14 â€‹% of cases. 97 â€‹% reported enhanced M&M presentations with the grading system, and 47 â€‹% reported a change in decision-making or practice style. Although post-implementation response rate was low, there were improvements in self-reported confidence and comfort in recognizing and discussing these issues. CONCLUSIONS: Implementation of the CHI-CS framework to discuss bias and access to care positively impacted the way providers view, discuss, and process health inequities.

4.
Vaccine ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39019657

RESUMO

BACKGROUND: To overcome supply issues of COVID-19 vaccines, this partially single blind, multi-centric, vaccine trial aimed to evaluate humoral immunogenicity using lower vaccine doses, intradermal vaccination, and heterologous vaccine schedules. Also, the immunity after a booster vaccination was assessed. METHODOLOGY: 566 COVID-19-naïve healthy adults were randomized to 1 of 8 treatment arms consisting of combinations of BNT162b2, mRNA-1273, and ChAdOx1-S. Anti-Receptor-Binding Domain immunoglobulin G (RBD IgG) titers, neutralizing antibody titres, and avidity of the anti-RBD IgGs was assessed up to 1 year after study start. RESULTS: Prolonging the interval between vaccinations from 28 to 84 days and the use of a heterologous BNT162b2 + mRNA-1273 vaccination schedule led to a non-inferior immune response, compared to the reference schedule. A low dose of mRNA-1273 was sufficient to induce non-inferior immunity. Non-inferiority could not be demonstrated for intradermal vaccination. For all adapted vaccination schedules, anti-RBD IgG titres measured after a first booster vaccination were non-inferior to their reference schedule. CONCLUSION: This study suggests that reference vaccine schedules can be adapted without jeopardizing the development of an adequate immune response. Immunity after a booster vaccination did not depend on the dose or brand of the booster vaccine, which is relevant for future booster campaigns. The trial is registered in the European Union Clinical Trials Register (number 2021-001993-52) and on clinicaltrials.gov (NCT06189040).

5.
Artigo em Inglês | MEDLINE | ID: mdl-39017861

RESUMO

PURPOSE OF REVIEW: Hip injuries in elite athletes are an increasingly recognized problem and range from chronic overuse injuries, such as adductor strains and labral tears, to acute traumatic injuries such as hip dislocations. In this article, we review common hip pathology experienced by elite athletes and sideline management of emergent hip injuries. RECENT FINDINGS: Elite athletes are subject to unique physical and mental stresses and therefore must be evaluated and treated in a unique manner. Hip and groin injuries account for approximately 6% of sport injuries overall and 3-15% of all injuries in professional sports. Hip sideline emergencies were rare but can include hip dislocations, subluxations, and avulsion fractures. Hip and groin injuries represent an important subset of injuries which can greatly impact an athlete's ability to perform. Understanding the physiology and types of hip/groin injuries, which athletes are prone to injuries, the impact on recovery time, recurrence risk, and the potential need for surgery aid sports medicine physicians in decision-making.

6.
J Clin Med ; 13(13)2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38999464

RESUMO

Background: Fabry disease (FD) is a rare X-linked lysosomal storage disorder that commonly manifests cardiovascular complications. We aimed to assess the prevalence of FD in a Chinese population with left ventricular hypertrophy (LVH) whilst implementing a gender-specific screening approach. Methods: Patients with LVH, defined as a maximum thickness of the left ventricular septal/posterior wall ≥ 13 mm, were considered eligible. All patients with hypertrophic cardiomyopathy (HCM) were excluded. Plasma α-galactosidase (α-GLA) enzyme activity was assessed using a dried blood spot test. Males with low enzyme activity underwent genetic testing to confirm a diagnosis of FD whereas females were screened for both α-GLA and globotriaosylsphingosine concentration and underwent genetic analysis of the GLA gene only if testing positive for ≥1 parameter. Results: 426 unrelated patients (age = 64.6 ± 13.0 years; female: male = 113:313) were evaluated. FD was diagnosed in 3 unrelated patients (age = 69.0 ± 3.5 years, female: male = 1:2) and 1 related female subject (age = 43 years). Genetic analyses confirmed the late-onset cardiac variant GLA c.640-801G>A (n = 3) and the missense variant c.869T>C associated with classic FD (n = 1). Cardiac complications were the only significant findings associated with the late-onset c.640-801G>A mutation, manifesting as mild or severe concentric LVH. In contrast, the classic c.869T>C mutation FD exhibited multisystemic manifestations in addition to severe concentric LVH. Conclusions: The prevalence of FD is lower in Chinese patients with LVH when HCM is excluded. The pathological variant c.640-801G>A remains the most common cause of late-onset FD, while the detection of FD in females can be improved by utilizing a gender-specific screening method.

7.
Br J Cancer ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971950

RESUMO

BACKGROUND: Combining PARP inhibitors (PARPis) with immune checkpoint inhibitors may improve clinical outcomes in selected cancers. We evaluated rucaparib and atezolizumab in advanced gynaecological or triple-negative breast cancer (TNBC). METHODS: After identifying the recommended dose, patients with PARPi-naive BRCA-mutated or homologous recombination-deficient/loss-of-heterozygosity-high platinum-sensitive ovarian cancer or TNBC received rucaparib plus atezolizumab. Tumour biopsies were collected pre-treatment, during single-agent rucaparib run-in, and after starting combination therapy. RESULTS: The most common adverse events with rucaparib 600 mg twice daily and atezolizumab 1200 mg on Day 1 every 3 weeks were gastrointestinal effects, fatigue, liver enzyme elevations, and anaemia. Responding patients typically had BRCA-mutated tumours and higher pre-treatment tumour levels of PD-L1 and CD8 + T cells. Markers of DNA damage repair decreased during rucaparib run-in and combination treatment in responders, but typically increased in non-responders. Apoptosis signature expression showed the reverse. CD8 + T-cell activity and STING pathway activation increased during rucaparib run-in, increasing further with atezolizumab. CONCLUSIONS: In this small study, rucaparib plus atezolizumab demonstrated acceptable safety and activity in BRCA-mutated tumours. Increasing anti-tumour immunity and inflammation might be a key mechanism of action for clinical benefit from the combination, potentially guiding more targeted development of such regimens. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03101280).

9.
J Anim Sci ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028632

RESUMO

Our study objectives were to evaluate the effects of divergent rates of body weight (BW) gain during early gestation in beef heifers on F0 performance, metabolic and endocrine status, colostrum immunoglobulins, and subsequent F1 calf characteristics, growth performance, concentrations of hormones and metabolites, and response to vaccination. Angus-based heifers (n = 100; BW = 369 ± 2.5 kg) were adapted to individual feeding for 14 d and bred using artificial insemination with female-sexed semen. Heifers were ranked by BW assigned to either a basal diet targeting 0.28 kg/d gain (LG, n = 50) or the basal diet plus an energy/protein supplement targeting 0.79 kg/d gain (MG, n = 50) until d 84 of gestation. Dam BW and blood samples were collected at 6 time points during gestation; body composition was evaluated at d -10 and 84; and fetal measurements were taken on d 42, 63, and 84. At calving (LG, n = 23; MG, n = 23), dam and calf BW were recorded; and colostrum, calf body measurements, and blood samples were collected. Cow-calf pairs were managed on a common diet from calving to weaning, followed by a common postnatal development period for all F1 female offspring. Growth performance, hormone and metabolite profiles, feeding behavior, and reproductive performance were assessed from birth to pre-breeding in F1 heifers. Offspring were vaccinated against respiratory disease and bovine viral diarrhea pathogens on d 62.3 ± 4.13 and 220.3 ± 4.13 post-calving. By design, MG dams were heavier (P < 0.0001) than LG at d 84, and the BW advantage persisted until subsequent weaning of F1 calves. Concentrations of serum IGF-1 and glucose were increased throughout gestation (P < 0.001) for MG dams, whereas concentrations of NEFA were decreased (P < 0.001) in LG dams. Calves from MG dams were 2.14 kg heavier (P = 0.03) and had larger chest circumference (P = 0.04) at birth compared with LG cohorts. Heifers from MG dams continued to have greater (P ≤ 0.03) BW gain and feed efficiency during the development period, but no differences were observed (P ≥ 0.13) in body composition, concentrations of hormones and metabolites, feeding behavior, puberty attainment, and response to vaccination in F1 offspring. Hence, early gestation rate of gain impacted BW and concentrations of glucose and IGF-1 throughout gestation in the F0 dam, resulting in altered F1 calf BW and measurements at birth and increased gain and efficiency during the development period.

10.
J Orthop ; 57: 137-146, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39035782

RESUMO

Introduction: There is conflicting evidence in the literature regarding the clinical utility of tourniquets in total knee arthroplasty (TKA), specifically in regards to perioperative blood loss. In this meta-analysis and systematic review, we aim to evaluate the clinical advantages and disadvantages associated with tourniquet use in the setting of TKA. Methods: A systematic review was conducted through April 2017 using keywords: "tourniquet" and "total knee arthroplasty" or "total knee replacement". Perioperative variables including TXA use, blood loss, incidence of venous thromboembolism (VTE), and wound complications were either extracted from the studies or corresponding authors were contacted. A sub-analysis was conducted to evaluate the effects of TXA on intraoperative and total blood loss (TBL), and VTE incidence. Results: After review of 558 articles, 19 studies reporting outcomes in 1094 patients were analyzed. Intraoperative blood loss was significantly lower in the tourniquet cohorts compared to non-tourniquet (p < 0.01). TBL was reduced in tourniquet groups but not significantly (p = 0.08). In contrast, calculated blood loss was greater in tourniquet groups, but this difference was not significant (p = 0.43). There was a greater likelihood for wound complications and VTE among tourniquet assisted TKA, albeit only significant for the former (p = 0.01). TXA sub-analysis demonstrated intraoperative blood loss was significantly reduced with tourniquet use regardless of TXA implementation (p < 0.01). In studies without TXA, tourniquet patients were at greater risk of developing VTE (p = 0.08). These risks decreased with TXA administration. Conclusion: This meta-analysis demonstrates that tourniquets prevent intraoperative blood loss, yet within the postoperative period, there is no significant difference in TBL between tourniquet and non-tourniquet assisted TKA. Level of evidence: Level II; Systematic Review and Meta-Analysis.

11.
Commun Med (Lond) ; 4(1): 113, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867000

RESUMO

BACKGROUND: Optimizing resuscitation to reduce inflammation and organ dysfunction following human trauma-associated hemorrhagic shock is a major clinical hurdle. This is limited by the short duration of pre-clinical studies and the sparsity of early data in the clinical setting. METHODS: We sought to bridge this gap by linking preclinical data in a porcine model with clinical data from patients from the Prospective, Observational, Multicenter, Major Trauma Transfusion (PROMMTT) study via a three-compartment ordinary differential equation model of inflammation and coagulation. RESULTS: The mathematical model accurately predicts physiologic, inflammatory, and laboratory measures in both the porcine model and patients, as well as the outcome and time of death in the PROMMTT cohort. Model simulation suggests that resuscitation with plasma and red blood cells outperformed resuscitation with crystalloid or plasma alone, and that earlier plasma resuscitation reduced injury severity and increased survival time. CONCLUSIONS: This workflow may serve as a translational bridge from pre-clinical to clinical studies in trauma-associated hemorrhagic shock and other complex disease settings.


Research to improve survival in patients with severe bleeding after major trauma presents many challenges. Here, we created a computer model to simulate the effects of severe bleeding. We refined this model using data from existing animal studies to ensure our simulations were accurate. We also used patient data to further refine the simulations to accurately predict which patients would live and which would not. We studied the effects of different treatment protocols on these simulated patients and show that treatment with plasma (the fluid portion of blood that helps form blood clots) and red blood cells jointly, gave better results than treatment with intravenous fluid or plasma alone. Early treatment with plasma reduced injury severity and increased survival time. This modelling approach may improve our ability to evaluate new treatments for trauma-associated bleeding and other acute conditions.

12.
Mult Scler Relat Disord ; 88: 105715, 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38889558

RESUMO

BACKGROUND: The Multiple Sclerosis Walking Scale-12 (MSWS-12) has typically been delivered through paper-and-pencil or computer-based administration. PURPOSE: This study examined the validity of inferences from scores derived via a telephone administration of the MSWS-12 applied as part of screening of participants with walking dysfunction into a clinical trial of exercise training in MS. METHOD: The MSWS-12 was administered on two occasions separated by approximately 2 weeks through the telephone and then in-person (i.e., computer-based administration). Participants further completed the Patient Determined Disease Steps (PDDS) scale, timed 25-foot walk (T25FW), six-minute walk (6MW), Modified Fatigue Impact Scale (MFIS), and Multiple Sclerosis Impact Scale-29 (MSIS-29), and underwent a neurological exam for generating an expanded disability status scale (EDSS) score. The primary set of data (Full Sample) for analyses included all persons who passed the telephone screening for inclusion with MSWS-12 scores between 25 and 75 (N = 374). The secondary set of data (Truncated Sample) included only persons with MSWS-12 scores between 25 and 75 for both the telephone and computer administrations of the MSWS-12 (N = 248). RESULTS: The results in the Full Sample indicated a difference in overall and item levels scores between the telephone and computer data collections, and the computer version had higher internal consistency and stronger unidimensionality. Nevertheless, MSWS-12 scores from both modes of administration had comparable correlations with the T25FW, 6MW, EDSS, PDDS, MFIS, and MSIS-29, but the correlation between the two MSWS-12 administrations did not approach unity. There was a systematic difference in scores between telephone and computer administrations across levels of walking dysfunction based on a Bland-Altman plot, and the difference was predicted by MFIS physical, 6MW, and EDSS scores. The comparison of results between the Full and Truncated Samples suggested that the primary analysis might have been influenced by the larger range of scores on the computer than telephone administrations of the MSWS-12. CONCLUSION: The telephone administration of the MSWS-12 provides an efficient and cost-effective measure of walking dysfunction in persons with MS.

13.
Proc Natl Acad Sci U S A ; 121(27): e2320454121, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38923983

RESUMO

Biologically detailed models of brain circuitry are challenging to build and simulate due to the large number of neurons, their complex interactions, and the many unknown physiological parameters. Simplified mathematical models are more tractable, but harder to evaluate when too far removed from neuroanatomy/physiology. We propose that a multiscale model, coarse-grained (CG) while preserving local biological details, offers the best balance between biological realism and computability. This paper presents such a model. Generally, CG models focus on the interaction between groups of neurons-here termed "pixels"-rather than individual cells. In our case, dynamics are alternately updated at intra- and interpixel scales, with one informing the other, until convergence to equilibrium is achieved on both scales. An innovation is how we exploit the underlying biology: Taking advantage of the similarity in local anatomical structures across large regions of the cortex, we model intrapixel dynamics as a single dynamical system driven by "external" inputs. These inputs vary with events external to the pixel, but their ranges can be estimated a priori. Precomputing and tabulating all potential local responses speed up the updating procedure significantly compared to direct multiscale simulation. We illustrate our methodology using a model of the primate visual cortex. Except for local neuron-to-neuron variability (necessarily lost in any CG approximation) our model reproduces various features of large-scale network models at a tiny fraction of the computational cost. These include neuronal responses as a consequence of their orientation selectivity, a primary function of visual neurons.


Assuntos
Modelos Neurológicos , Neurônios , Córtex Visual , Animais , Neurônios/fisiologia , Córtex Visual/fisiologia , Humanos , Rede Nervosa/fisiologia , Córtex Cerebral/fisiologia , Simulação por Computador
14.
Int J Infect Dis ; : 107132, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38942168

RESUMO

OBJECTIVE: The 2022 mpox epidemic reached a peak in Belgium and the rest of Europe in July 2022, after which it unexpectedly subsided. This study investigates epidemiological, behavioral, and immunological factors behind the waning of the epidemic in Belgium. METHODS: We investigated temporal evolutions in the characteristics and behavior of mpox patients using national surveillance data and data from a prospective registry of mpox patients in the Institute of Tropical Medicine (Antwerp). We studied behavioral changes in the population at risk using a survey among HIV-pre-exposure prophylaxis (PrEP) users. We determined the seroprevalence of anti-orthopoxvirus antibodies among HIV-PrEP users across four time points in 2022. RESULTS: Mpox patients diagnosed at the end of the epidemic had less sexual risk behavior compared to those diagnosed earlier: they engaged less in sex at mass events, had fewer sexual partners and were less likely to belong to the sexual network's central group. Among HIV-PrEP users there were no notable changes in sexual behavior. Anti-orthopoxvirus seroprevalence did not notably increase before the start of national vaccination campaigns. CONCLUSION: The observed changes in group immunity and behavior in the population at greater risk of exposure to mpox seem unable to explain the waning of the mpox epidemic. A change in the profile of mpox patients might have contributed to the decline in cases.

15.
bioRxiv ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38915563

RESUMO

The amygdala responds to a large variety of socially and emotionally salient environmental and interoceptive stimuli. The context in which these stimuli occur determines their social and emotional significance. In canonical neurophysiological studies, the fast-paced succession of stimuli and events induce phasic changes in neural activity. During inter-trial intervals neural activity is expected to return to a stable and relatively featureless baseline. Context, such as the presence of a social partner, or the similarity of trials in a blocked design, induces brain states that can transcend the fast-paced succession of stimuli and can be recovered from the baseline firing rate of neurons. Indeed, the baseline firing rates of neurons in the amygdala change between blocks of trials of gentle grooming touch, delivered by a trusted social partner, and non-social airflow stimuli, delivered by a computer-controlled air valve. In this experimental paradigm, the presence of the groomer alone was sufficient to induce small but significant changes in baseline firing rates. Here, we examine local field potentials (LFP) recorded during these baseline periods to determine whether context was encoded by network dynamics that emerge in the local field potentials from the activity of large ensembles of neurons. We found that machine learning techniques can reliably decode social vs. non-social context from spectrograms of baseline local field potentials. Notably, decoding accuracy improved significantly with access to broad-band information. No significant differences were detected between the nuclei of the amygdala that receive direct or indirect inputs from areas of the prefrontal cortex known to coordinate flexible, context-dependent behaviors. The lack of nuclear specificity suggests that context-related synaptic inputs arise from a shared source, possibly interoceptive inputs that signal the sympathetic- vs. parasympathetic-dominated states characterizing non-social and social blocks, respectively.

16.
JAAD Int ; 16: 97-102, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38868400

RESUMO

Background: Chronic pruritus (CP) is a poorly characterized condition associated with intense pruritus without a primary skin eruption. This condition tends to emerge more commonly in older adults, and there is limited research on triggering factors. Objective: To explore the clinical characteristics and pathophysiology of CP following exposure to an immune stimulus. Methods: Clinical characteristics and plasma samples were collected from 15 patients who developed CP following an immune stimulus such as checkpoint inhibitors or vaccination. A multiplex panel was used to analyze plasma cytokine concentrations within these patients. Results: Most immunotherapy-treated patients experienced CP during treatment or after 21 to 60 days of receiving treatment, while vaccine-stimulated patients developed pruritus within a week of vaccination. Plasma cytokine analysis revealed elevated levels of 12 cytokines in patients with immune-stimulated CP compared to healthy controls. Notably, T helper 2 (Th2) related cytokines interleukin (IL)-5 (fold change 2.65; q < 0.25) and thymic stromal lymphopoietin (fold change 1.61 q < 0.25) were upregulated. Limitations: Limitations of this study include limited sample size, particularly in the plasma cytokine assay. Conclusions and Relevance: This study reveals triggers of CP development and describes alterations in blood Th2 markers in patients with CP, including IgE, increased blood eosinophils, and cytokines IL-5 and thymic stromal lymphopoietin.

17.
Biol Reprod ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857377

RESUMO

Over 35% of reproductive-age women in the US are obese, putting them at increased risk for numerous obstetric complications due to abnormal labor. While the association between maternal obesity and abnormal labor has been well documented, the mechanisms responsible for this remain understudied. The uterine smooth muscle, myometrium, has high energy needs in order to fuel regular uterine contractions during parturition. However, the precise mechanisms by which the myometrium meets its energy demands has not been defined. Here, our objective was to define the effects of obesity on energy utilization in the myometrium during labor. We generated a mouse model of maternal diet-induced obesity (DIO) and found that these mice had a higher rate of dystocia than control chow-fed (CON) mice. Moreover, compared to CON mice, DIO mice at term, both before and during labor had lower in vivo spontaneous uterine contractility. Untargeted transcriptomic and metabolomic analyses suggest that DIO is associated with elevated long-chain fatty acid uptake and utilization in the uterus, but also an accumulation of medium-chain fatty acids. DIO uteri also had an increase in the abundance of long chain-specific ß-oxidation enzymes, which may be responsible for the observed increase in long-chain fatty acid utilization. This altered energy substrate utilization may be a contributor to the observed contractile dysfunction.

18.
Nat Chem ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858518

RESUMO

Adding synthetic nucleotides to DNA increases the linear information density of DNA molecules. Here we report that it also can increase the diversity of their three-dimensional folds. Specifically, an additional nucleotide (dZ, with a 5-nitro-6-aminopyridone nucleobase), placed at twelve sites in a 23-nucleotides-long DNA strand, creates a fairly stable unimolecular structure (that is, the folded Z-motif, or fZ-motif) that melts at 66.5 °C at pH 8.5. Spectroscopic, gel and two-dimensional NMR analyses show that the folded Z-motif is held together by six reverse skinny dZ-:dZ base pairs, analogous to the crystal structure of the free heterocycle. Fluorescence tagging shows that the dZ-:dZ pairs join parallel strands in a four-stranded compact down-up-down-up fold. These have two possible structures: one with intercalated dZ-:dZ base pairs, the second without intercalation. The intercalated structure would resemble the i-motif formed by dC:dC+-reversed pairing at pH ≤ 6.5. This fZ-motif may therefore help DNA form compact structures needed for binding and catalysis.

19.
Virol J ; 21(1): 138, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872127

RESUMO

BACKGROUND: Infection with SARS-CoV-2 in high-risk groups such as kidney transplant and dialysis patients is shown to be associated with a more serious course of the disease. Four years after the start of the COVID-19 pandemic, crucial knowledge on the immune responses in these patient groups is still lacking. Therefore, this study aimed at investigating the humoral immune response after a SARS-CoV-2 infection compared to vaccination as well as the evolution of immunoglobulins over time. METHODS: Kidney transplant recipients, patients on haemodialysis or on peritoneal dialysis and healthy controls were included in this longitudinal multicenter study. SARS-CoV-2 anti-RBD, anti-NP and anti-S1S2 immunoglobulin G (IgG) and A (IgA) as well as the neutralizing antibody capacity were measured. RESULTS: Kidney transplant recipients had a significantly better humoral response to SARS-CoV-2 after infection (86.4%) than after a two-dose mRNA vaccination (55.8%) while seroconversion was comparable in patients on haemodialysis after infection (95.8%) versus vaccination (89.4%). In individuals without prior COVID-19, the IgG levels after vaccination were significantly lower in kidney transplant recipients when compared to all other groups. However, the IgA titres remained the highest in this patient group at each time point, both after infection and vaccination. A history COVID-19 was associated with higher antibody levels after double-dose vaccination in all patient categories and, while decreasing, titres remained high six months after double-dose vaccination. CONCLUSION: Kidney transplant recipients had a more robust humoral response to SARS-CoV-2 following infection compared to a two-dose mRNA vaccination, while patients on haemodialysis exhibited comparable seroconversion rates. Notably, individuals with prior COVID-19 exhibited higher IgG levels in response to vaccination. Hybrid immunity is thus the best possible defence against severe COVID-19 disease and seems also to hold up for these populations. Next, it is not clear whether the higher IgA levels in the kidney transplant recipients is beneficial for neutralizing SARS-CoV-2 or if it is a sign of disease severity.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , COVID-19 , Imunidade Humoral , Imunoglobulina A , Imunoglobulina G , Transplante de Rim , Diálise Renal , SARS-CoV-2 , Transplantados , Vacinação , Humanos , Transplante de Rim/efeitos adversos , COVID-19/imunologia , COVID-19/prevenção & controle , Imunoglobulina G/sangue , Masculino , Feminino , Imunoglobulina A/sangue , Pessoa de Meia-Idade , Anticorpos Antivirais/sangue , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Idoso , Adulto , Estudos Longitudinais , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Glicoproteína da Espícula de Coronavírus/imunologia
20.
Disabil Health J ; : 101643, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38853095

RESUMO

BACKGROUND: There is a high prevalance of hypertension in adults with with cerebral palsy (CP). However, less is known about blood pressure in children with CP. OBJECTIVE: The aim was to determine if blood pressure is elevated in children with CP and whether it is related to adiposity and physical activity. METHODS: Thirty children with spastic CP (5-11 y) and 30 age-, sex-, and race-matched typically developing control children were studied. Resting systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate were measured, and mean arterial pressure (MAP) was calculated. Visceral fat mass and total body fat mass index (FMI) were determined using dual-energy X-ray absorptiometry. Physical activity was assessed using accelerometer-based monitors. RESULTS: Children with CP had higher DBP and heart rate than controls (p < 0.05). DBP percentile and MAP were also higher in children with CP when BMI was statistically controlled. Children with CP and elevated blood pressure or hypertension (n = 8) had 56% more visceral fat mass than children with CP and normal blood pressure (n = 22; p < 0.05). In the groups combined, blood pressure was directly related to visceral fat mass and FMI, and inversely related to physical activity (p < 0.05). However, in children with CP alone, only visceral fat mass was related to blood pressure (p < 0.05). CONCLUSIONS: Children with CP have higher resting blood pressure than typically developing children. The higher blood pressure is related to higher visceral adiposity. Careful blood pressure screening should start during childhood in individuals with CP.

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