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1.
Australas J Dermatol ; 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39101303

ABSTRACT

Children and adolescents suffering from moderate-to-severe atopic dermatitis (AD) face a significant disease burden that greatly impacts their quality of life. Treatment options for AD are currently limited. To assess the safety and efficacy of biologic drugs, dupilumab, lebrikizumab, or tralokinumab, in improving outcomes in patients with moderate to severe inadequately controlled AD. We searched PubMed, Embase and Cochrane databases for randomized controlled trials (RCTs) comparing dupilumab, lebrikizumab or tralokinumab to placebo in patients with AD. We computed odds ratios (ORs) for binary endpoints, with 95% confidence intervals (CIs), random effects model was used and a p-value <0.05 was considered as statistically significant. We analysed data into Review Manager 5.4. A total of five RCTs and 973 patients were included, of whom 592 were prescribed a biologic drug. Compared with placebo, patients receiving a biologic drug had a greater improvement, achieved an Investigator Global Assessment (IGA) score of 0 or 1 (OR 5.05; 95% CI 3.08-8.29), Eczema Area and Severity Index (EASI) 75 (OR 6.87; 95% CI 4.71-10.02), EASI 50 (OR 8.89; 95% CI 6.18-12.78) and EASI 90 (8.30; 95% CI 4.81-14.31). The proportion of patients with 3 points or more (OR 6.56; 95% CI 4.34-9.90) or 4 points or more (OR 8.09; 95% CI 5.19-12.59) improvement from baseline in peak pruritus NRS was significantly higher with biologic drugs than placebo. There were no significant differences between groups regarding adverse events (OR 0.79; 95% CI 0.58-1.07), and conjunctivitis (OR 2.08; 95% CI 1.00-4.33). In this meta-analysis, dupilumab, lebrikizumab, and tralokinumab have shown significant improvements in signs, symptoms and quality of life in children or adolescents with moderate to severe AD. Larger studies may be needed to continue evaluating the safety and efficacy of these biologic drugs in this patient population.

2.
Nurs Inq ; : e12665, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39138913

ABSTRACT

The purpose of this study is to understand institutional violence (IV) in the relationships between health professionals, hospitalized children, and family members. This is a qualitative study developed at the pediatric inpatient unit of a university hospital in the city of Salvador, Bahia, Brazil. The research participants consisted of 39 health professionals who specialized in pediatrics and 10 family members of hospitalized children. Semi-structured interviews were the method used for data collection. Using discourse analysis as a basis and taking a Foucauldian perspective, the researchers observed that the expressions of IV could be traced to abusive power relations within the system. We found four discursive forms within the data set: communication problems as IV, violence through inattention and neglect, violence as an action and consequent materialization on the body, and psychological violence as a submission mechanism. Based on these findings, we argue that professionals, managers, the scientific community, and users might be able to better guarantee the safety of children by recognizing IV and effectively intervening in it.

3.
Cureus ; 16(7): e64231, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39130944

ABSTRACT

Spontaneous remission of Cushing's disease (CD) is uncommon and often attributed to pituitary tumor apoplexy. We present a case involving a 14-year-old female who exhibited clinical features of Cushing's syndrome. Initial diagnostic tests indicated CD: elevated 24h urinary cortisol (235 µg/24h, n < 90 µg/24h), abnormal 1 mg dexamethasone overnight test (cortisol after 1 mg dex 3.4 µg/dL, n < 1.8 µg/dL), and elevated adrenocorticotropic hormone concentrations (83.5 pg/mL, n 10-60 pg/mL). A pituitary adenoma was suspected, so a nuclear MRI was performed, with findings suggestive of a pituitary microadenoma. The patient was referred for a transsphenoidal resection of the microadenoma. While waiting for surgery, the patient presented to the emergency department with a headache and clinical signs of meningism. A computed axial tomography of the central nervous system was performed, and no structural alterations were found. The symptoms subsided with analgesia. One month later, she presented again to the emergency department with clinical findings of acute adrenal insufficiency (cortisol level of 4.06 µg/dL), and she was noted to have spontaneous biochemical remission associated with the resolution of her symptoms of hypercortisolism. For that reason, spontaneous CD remission induced by pituitary apoplexy (PA) was diagnosed. The patient has been managed conservatively since the diagnosis and remains in clinical and biochemical remission until the present time, after 10 months of follow-up. There are three unique aspects of our case: the early age of onset of symptoms, the spontaneous remission of CD due to PA, which has been rarely reported in the medical literature, and the fact that the patient presented a microadenoma because there are fewer than 10 clinical case reports of PA associated with microadenoma.

4.
Article in English | MEDLINE | ID: mdl-39126576

ABSTRACT

Nanoparticulate drug delivery systems (NDDS) based nanoformulations have emerged as promising drug delivery systems. Various NDDS-based formulations have been reported such as polymeric nanoparticles (NPs), nanoliposomes, solid lipid NPs, nanocapsules, liposomes, self-nano emulsifying drug delivery systems, pro liposomes, nanospheres, microemulsion, nanoemulsion, gold NPs, silver NPs and nanostructured lipid carrier. They have shown numerous advantages such as enhanced bioavailability, aqueous solubility, permeability, controlled release profile, and blood-brain barrier (BBB) permeability. This advantage of NDDS can help to deliver pure drugs to the target site. However, the formulation of nanoparticles is a complex process that requires optimization to ensure product quality and efficacy. Quality by Design (QbD) is a systemic approach that has been implemented in the pharmaceutical industry to improve the quality and reliability of drug products. QbD involves the optimization of different parameters like zeta potential (ZP), particle size (PS), entrapment efficiency (EE), polydispersity index (PDI), and drug release using statistical experimental design. The present article discussed the detailed role of QbD in optimizing nanoformulations and their advantages, advancement, and applications from the industrial perspective. Various case studies of QbD in the optimization of nanoformulations are also discussed.

5.
Fitoterapia ; : 106183, 2024 Aug 12.
Article in English | MEDLINE | ID: mdl-39142528

ABSTRACT

Two new heptapeptides, [1-7-NαC]-crocaorbs A1 (1) and A2 (2), were isolated from the latex of Croton campanulatus. Their structures were determined using NMR spectroscopic techniques, ESI-HRMS data, Marfey's method, and further refined using molecular dynamics with simulated annealing (MD/SA). Molecular dynamics calculations of peptides 1 and 2 demonstrated greater stability in simulations using a biological solvent compared to those using DMSO. Compound 1, the most abundant peptide in latex, was assessed for NO production, antiplasmodial and cytotoxicity activities. The peptide significantly increased nitric oxide (NO) production at concentrations of 40, 20 or 10 µM (17.932 ±â€¯1.1, 18.270 ±â€¯0.9, 18.499 ±â€¯0.7, respectively). Its antiplasmodial activity exhibited limited efficacy, with only 5% inhibition of Plasmodium falciparum 3D7 growth at a concentration of 50 µM. Also, it exhibited no cytotoxic effects in the J774A.1 murine macrophages cell line. This study represents the first report of a phytochemical investigation of the species C. campanulatus, which showed orbitides with distinctive sequences in contrast to other peptides described for the genus Croton and contributes to the study of structural diversity within this particular class of compounds.

6.
Rev Bras Epidemiol ; 27: e240041, 2024.
Article in English, Portuguese | MEDLINE | ID: mdl-39140578

ABSTRACT

OBJECTIVE: To analyze the association of food insecurity (FI) with chronic noncommunicable diseases (NCDs) in the Brazilian context. METHODS: The review protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO). The searches were conducted in LILACS and PubMed databases (September/2022). Observational studies carried out in the Brazilian population published since 2003 were included, in which: (1) the association of FI with NCDs was analyzed; and (2) the Brazilian Food Insecurity Scale was used. Studies on pregnant women and those that associated FI with cancer, sexually transmitted infections, and musculoskeletal and respiratory diseases were excluded. The studies were subjected to methodological quality assessment. RESULTS: A total of 27 cross-sectional studies were included; nine used secondary data from national surveys, and the others used primary data. An association between FI and overweight and obesity in different age groups was verified in the studies. CONCLUSION: The included articles did not produce evidence on other NCDs of interest to health in Brazil such as diabetes and high blood pressure. However, they corroborate the already-known relationship between obesity and FI. Studies on the topic, with a longitudinal design, should be encouraged.


Subject(s)
Food Insecurity , Noncommunicable Diseases , Humans , Brazil/epidemiology , Noncommunicable Diseases/epidemiology , Chronic Disease/epidemiology , Obesity/epidemiology , Female , Cross-Sectional Studies , Risk Factors , Male
7.
Lasers Med Sci ; 39(1): 211, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39115705

ABSTRACT

PURPOSE: To evaluate the effect of post-surgical photobiomodulation therapy in dogs. METHODS: Twenty dogs were selected for elective gastropexy and randomly divided into a control (CG, n = 10) and a PBMT group (PBMTG, n = 10). Pre­medication consisted of medetomidine and butorphanol. Meloxicam was administered before the procedure. Induction was performed with propofol and maintained with sevoflurane. Local blocks with lidocaine were used. Incisional gastropexy was performed in all animals. PBMTG received PBMT immediately after surgery. The need for postoperative rescue analgesia, if the animal had eaten by the evaluation momen, and pain scores were collected using the Glasgow Composite Measure Pain Scale - Short Form (CMPS­SF) at 1, 2, 4, 6, 8, 12, 16, 20, and 24 h post­endotracheal extubation. CMPS­SF scores were compared with the Mann-Whitney Test and proportions of animals that required rescue analgesia and had eaten with a χ2 test. P was set at < 0.05. RESULTS: No rescue analgesia was needed for any animal. Still, significant differences were observed in CMPS-SF scores between CG and PBMTG between 1 and 4 h post-extubation. PBMTG had a significantly higher proportion of animals eating up to the 8 h post-extubation evaluation moment. CONCLUSION: Adding post-surgical photobiomodulation to a standard anesthesia and analgesia protocol reduced CMPS-SF scores and increased the proportion of animals that resumed eating compared to the standard protocol alone.


Subject(s)
Gastric Dilatation , Gastropexy , Low-Level Light Therapy , Stomach Volvulus , Low-Level Light Therapy/veterinary , Gastropexy/veterinary , Animals , Dogs , Gastric Dilatation/surgery , Stomach Volvulus/surgery , Medetomidine/administration & dosage , Meloxicam/administration & dosage , Butorphanol/administration & dosage , Propofol/administration & dosage , Sevoflurane/administration & dosage , Treatment Outcome , Anesthesia , Analgesia , Pain Measurement/veterinary , Analgesics/administration & dosage
9.
Cureus ; 16(7): e63735, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39099974

ABSTRACT

Pituitary carcinoma is a condition defined by metastasis of a pituitary tumor to a distant location, and it is a very rare type of adenohypophyseal tumor. We present a case of a 29-year-old female who was followed up in our Endocrinology Department. Past medical history included the diagnosis of Cushing disease and transsphenoidal tumor resection at 12 years of age, followed by transcranial resection two years later because of persistently elevated adrenocorticotropic hormone (ACTH). Despite the surgical management, the patient persisted with increased ACTH and hypercortisolism, and, thus, bilateral adrenalectomy was performed a year later. Two years after the procedure, the patient presented with a newly diagnosed pituitary macroadenoma, and the diagnosis of Nelson syndrome was made. Linear accelerator radiotherapy was given, which reduced the size of the tumor. Later, several imaging studies showed multiple lesions on the falx cerebri, posterior clinoid process, retroclival region, cerebellopontine angle, pterygopalatine fossa, infratentorial region, and posterior ethmoidal cells. Biopsy and immunohistochemistry of the falx cerebri lesions described ACTH-producing pituitary adenocarcinoma. Treatment was given with intramuscular octreotide, dabrafenib, and trametinib. Despite persistently elevated ACTH levels, the patient has since remained clinically stable, without new development or worsening of symptoms. There are three unique aspects of our case. First, we reported an unusual presentation of this disease, since the patient in our case was a female with an early age of onset. Second, this is the first reported case demonstrating pituitary carcinoma in the falx cerebri. Third, the prognosis of pituitary carcinoma is usually very poor, and mortality is extremely high; however, the patient in our case has been followed up for seven years since the diagnosis of the metastatic lesions and has remained clinically stable.

10.
Nature ; 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39146975

ABSTRACT

T cells in jawed vertebrates comprise two lineages, αß T-cells and γδ T-cells, defined by the antigen receptors they express, i.e., αß and γδ T-cell receptors (TCRs), respectively. The two lineages have different immunological roles, requiring γδ TCRs to recognize more structurally-diverse ligands1. Nevertheless, the receptors use shared CD3 subunits to initiate signaling. Whereas the structural organization of αß TCRs is understood2,3, the architecture of γδ TCRs is unknown. Here, we used cryogenic electron microscopy to determine the structure of a fully-assembled, MR1-reactive human Vδ3Vγ8 TCR/CD3δγε2ζ2 complex bound by anti-CD3ε antibody Fab fragments4,5. The arrangement of CD3 subunits in γδ and αß TCRs is conserved and, although the transmembrane α-helices of the TCR-γδ and -αß subunits differ markedly in sequence, the packing of the eight transmembrane-helix bundles is similar6. However, in contrast to the apparently rigid αß TCR2,3,6, the γδ TCR exhibits considerable conformational heterogeneity, owing to the ligand-binding TCR-γδ subunits being tethered to the CD3 subunits by their transmembrane regions only. Reducing this conformational heterogeneity by transferring the Vδ3Vγ8 TCR variable domains to an αß TCR enhanced receptor signaling, suggesting that γδ TCR organization reflects a compromise between efficient signaling and the ability to engage structurally-diverse ligands. Our findings reveal the remarkable structural plasticity of the TCR on evolutionary timescales, and recast it as a highly versatile receptor capable of initiating signaling as either a rigid or flexible structure.

11.
Life Sci ; : 122978, 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39147317

ABSTRACT

The cancer cell metabolism, notably characterized by the Warburg effect, has been the focus of intense investigation regarding the mechanisms of the uptake of glucose analogs, opening up perspectives for diagnosis and treatment of cancer disease. In this review, we delve into the ever-evolving landscape of cancer research, centering on fluorescent probes based on glucose analogs. These analogs, resulting from modifications in the carbohydrate structure with functional groups, have stood out as versatile molecules in applications ranging from disease comprehension to therapeutic innovation, especially when combined with fluorescent compounds. Fluorescence-based assays have provided valuable contributions to the revelation of complex biological mechanisms in life sciences. This review presents selected studies from about the past six years up to 2024 related to the use of glucose-based fluorescent probes for the investigation of their uptake profile as well as for therapeutic purposes. We believe that these investigations offer insights into the intricate interaction between glucose analogs and cancer cell metabolism, guiding future research and clinical applications in this field.

12.
BMJ Open Respir Res ; 11(1)2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39147399

ABSTRACT

OBJECTIVES: To investigate the associations of physical activity (PA) and sedentary behaviour in early childhood with asthma and reduced lung function in later childhood within a large collaborative study. DESIGN: Pooling of longitudinal data from collaborating birth cohorts using meta-analysis of separate cohort-specific estimates and analysis of individual participant data of all cohorts combined. SETTING: Children aged 0-18 years from 26 European birth cohorts. PARTICIPANTS: 136 071 individual children from 26 cohorts, with information on PA and/or sedentary behaviour in early childhood and asthma assessment in later childhood. MAIN OUTCOME MEASURE: Questionnaire-based current asthma and lung function measured by spirometry (forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity) at age 6-18 years. RESULTS: Questionnaire-based and accelerometry-based PA and sedentary behaviour at age 3-5 years was not associated with asthma at age 6-18 years (PA in hours/day adjusted OR 1.01, 95% CI 0.98 to 1.04; sedentary behaviour in hours/day adjusted OR 1.03, 95% CI 0.99 to 1.07). PA was not associated with lung function at any age. Analyses of sedentary behaviour and lung function showed inconsistent results. CONCLUSIONS: Reduced PA and increased sedentary behaviour before 6 years of age were not associated with the presence of asthma later in childhood.


Subject(s)
Asthma , Exercise , Sedentary Behavior , Humans , Child , Asthma/epidemiology , Asthma/physiopathology , Adolescent , Male , Child, Preschool , Europe/epidemiology , Female , Infant , Accelerometry , Longitudinal Studies , Surveys and Questionnaires , Forced Expiratory Volume , Spirometry , Infant, Newborn , Vital Capacity , Birth Cohort
13.
Braz Oral Res ; 38: e070, 2024.
Article in English | MEDLINE | ID: mdl-39109767

ABSTRACT

This study aimed to assess whether dentists correctly understand the benefit of a dental treatment when it is presented using absolute numbers or relative risk reduction (RRR). This parallel-group randomized controlled trial recruited dentists from 3 postgraduate courses in Rio de Janeiro, Brazil. Participants received, in sequentially numbered sealed opaque envelopes, the description of a hypothetical scenario of the benefit (avoidance of multiple tooth loss) of nonsurgical periodontal treatment without or with antibiotics. Treatment benefit was presented in 2 different formats: absolute numbers or RRR. Dentists were given 10 minutes to read the treatment scenario and answer 5 questions. The final sample for analysis included 101 dentists. When asked to estimate the number of patients out of 100 who would avoid multiple tooth loss without antibiotics, 17 dentists (33%) in the absolute numbers group and 12 (25%) in the RRR group provided the correct response (p = 0.39). Regarding treatment with antibiotics, 26 dentists (50%) in the absolute numbers group and 14 (29%) in the RRR group provided the correct response (p = 0.04). Only 16 dentists (31%) in the absolute numbers group and 12 (25%) in the RRR group gave correct answers for both questions (p = 0.51). Most dentists did not correctly understand the benefit of the treatment, irrespective of the format it was presented. Slightly more dentists correctly understood the benefit of the treatment when it was presented as absolute numbers than as RRR.


Subject(s)
Anti-Bacterial Agents , Dentists , Humans , Dentists/statistics & numerical data , Dentists/psychology , Female , Male , Anti-Bacterial Agents/therapeutic use , Brazil , Adult , Statistics, Nonparametric , Risk Reduction Behavior , Risk Assessment , Middle Aged , Periodontal Diseases/therapy , Periodontal Diseases/prevention & control , Tooth Loss/prevention & control , Health Knowledge, Attitudes, Practice , Clinical Competence/statistics & numerical data
14.
Front Immunol ; 15: 1423689, 2024.
Article in English | MEDLINE | ID: mdl-39040115

ABSTRACT

Purpose: Natural killer (NK) cells are traditionally identified by flow cytometry using a combination of markers (CD16/CD56/CD3), because a specific NK-cell marker is still missing. Here we investigated the utility of CD314, CD335 and NKp80, compared to CD16/CD56/CD3, for more robust identification of NK-cells in human blood, for diagnostic purposes. Methods: A total of 156 peripheral blood (PB) samples collected from healthy donors (HD) and patients with diseases frequently associated with loss/downregulation of classical NK-cell markers were immunophenotyped following EuroFlow protocols, aimed at comparing the staining profile of total blood NK-cells for CD314, CD335 and NKp80, and the performance of distinct marker combinations for their accurate identification. Results: NKp80 showed a superior performance (vs. CD314 and CD335) for the identification of NK-cells in HD blood. Besides, NKp80 improved the conventional CD16/CD56/CD3-based strategy to identify PB NK-cells in HD and reactive processes, particularly when combined with CD16 for further accurate NK-cell-subsetting. Although NKp80+CD16 improved the identification of clonal/tumor NK-cells, particularly among CD56- cases (53%), aberrant downregulation of NKp80 was observed in 25% of patients, in whom CD56 was useful as a complementary NK-cell marker. As NKp80 is also expressed on T-cells, we noted increased numbers of NKp80+ cytotoxic T-cells at the more advanced maturation stages, mostly in adults. Conclusion: Here we propose a new robust approach for the identification of PB NK-cells, based on the combination of NKp80 plus CD16. However, in chronic lymphoproliferative disorders of NK-cells, addition of CD56 is recommended to identify clonal NK-cells, due to their frequent aberrant NKp80- phenotype.


Subject(s)
Immunophenotyping , Killer Cells, Natural , Humans , Killer Cells, Natural/immunology , Male , Adult , Female , Middle Aged , Neoplasms/immunology , Neoplasms/diagnosis , Flow Cytometry/methods , Young Adult , Aged , Biomarkers , Adolescent , GPI-Linked Proteins/blood , Lectins, C-Type , Receptors, Natural Killer Cell , B7 Antigens
16.
Front Public Health ; 12: 1389641, 2024.
Article in English | MEDLINE | ID: mdl-38952731

ABSTRACT

Aims: To assess the impact of the COVID-19 pandemic on the health condition of people ≥75 years of age and on their family caregivers in Spain. Design: Multicentric, mixed method concurrent study. Methods: This work, which will be conducted within the primary care setting in 11 administrative regions of Spain, will include three coordinated studies with different methodologies. The first is a population-based cohort study that will use real-life data to analyze the rates and evolution of health needs, care provision, and services utilization before, during, and after the pandemic. The second is a prospective cohort study with 18 months of follow-up that will evaluate the impact of COVID-19 disease on mortality, frailty, functional and cognitive capacity, and quality of life of the participants. Finally, the third will be a qualitative study with a critical social approach to understand and interpret the social, political, and economic dimensions associated with the use of health services during the pandemic. We have followed the SPIRIT Checklist to address trial protocol and related documents. This research is being funded by the Instituto de Salud Carlos III since 2021 and was approved by its ethics committee (June 2022). Discussion: The study findings will reveal the long-term impact of the COVID-19 pandemic on the older adults and their caregivers. This information will serve policymakers to adapt health policies to the needs of this population in situations of maximum stress, such as that produced by the COVID-19 pandemic. Trial Registration: Identifier: NCT05249868 [ClinicalTrials.gov].


Subject(s)
COVID-19 , Self Care , Humans , COVID-19/epidemiology , Spain/epidemiology , Aged , Prospective Studies , Caregivers/statistics & numerical data , Caregivers/psychology , Female , Aged, 80 and over , Quality of Life , Male , Health Status , SARS-CoV-2 , Pandemics , Primary Health Care/statistics & numerical data
17.
Polymers (Basel) ; 16(13)2024 Jul 02.
Article in English | MEDLINE | ID: mdl-39000753

ABSTRACT

Simvastatin (SIM) is widely prescribed to treat hyperlipidemia, despite its limitations, such as a short half-life and low oral bioavailability. To overcome these drawbacks, the development of a controlled-release formulation is desirable. This study aims to develop a microparticulate system based on cellulose acetate (ACT) obtained from Agave sisalana Perrine to promote a controlled SIM release. SIM-loaded microparticles (SMP) were prepared using the solvent emulsification-evaporation method. Several parameters were evaluated, including particle size, surface charge, morphology, encapsulation efficiency, thermochemical characteristics, crystallinity, and in vitro release profile. ACT exhibited favorable flow properties after acetylation, with a degree of substitution values superior to 2.5, as confirmed by both the chemical route and H-NMR, indicating the formation of cellulose triacetate. The obtained SMP were spherical with an average size ranging from 1842 to 1857 nm, a zeta potential of -4.45 mV, and a high SIM incorporation efficiency (98%). Thermal and XRD analyses revealed that SIM was homogeneously dispersed into the polymeric matrix in its amorphous state. In vitro studies using dialysis bags revealed that the controlled SIM release from microparticles was higher under simulated intestinal conditions and followed the Higuchi kinetic model. Our results suggest that ACT-based microparticles are a promising system for SIM delivery, which can improve its bioavailability, and result in better patient compliance.

18.
Biology (Basel) ; 13(7)2024 Jun 26.
Article in English | MEDLINE | ID: mdl-39056666

ABSTRACT

This study evaluated the bone incorporation process of a screw-shaped internal fixation device made of poly (L-lactide-co-D, L-lactide) (PLDLLA). Thirty-two male Wistar rats received 32 fixation devices (2 mm × 6 mm) randomly assigned to either the right or left tibia and one implant in each animal. After 7, 14, 28, and 42 days, the rats were euthanized and the specimens were subjected to microtomographic computed tomography (microCT) and histomorphometric analyses to evaluate bone interface contact (BIC%) and new bone formation (NBF%) in cortical and cancellous bone areas. The animals euthanized on days 28 and 42 were treated with calcein and alizarin red, and confocal LASER microscopy was performed to determine the mineral apposition rate (MAR). Micro-CT revealed a higher percentage of bone volume (p < 0.006), trabecular separation (p < 0.001), and BIC in the cortical (p < 0.001) and cancellous (p = 0.003) areas at 28 and 42 days than at 7 and 14 days. The cortical NBF at 42 days was greater than that at 7 and 14 days (p = 0.022). No statistically significant differences were observed in cancellous NBF or MAR at 28 and 42 days. Based on these results, it can be seen that the PLDLLA internal fixation device is biocompatible and allows new bone formation around the screw thread.

19.
Biology (Basel) ; 13(7)2024 Jul 17.
Article in English | MEDLINE | ID: mdl-39056725

ABSTRACT

(1) Objective: The aim of this study was to assess the biological behavior of bone tissue on a machined surface (MS) and modifications made by a laser beam (LS) and by a laser beam incorporated with hydroxyapatite (HA) using a biomimetic method without thermic treatment (LHS). (2) Methods: Scanning electron microscopy coupled with energy-dispersive X-ray spectrometry (SEM/EDX) was performed before and after installation in the rabbit tibiae. A total of 20 Albinus rabbits randomly received 30 implants of 3.75 × 10 mm in the right and left tibias, with two implants on each surface in each tibia. In the animals belonging to the 4-week euthanasia period group, intramuscular application of the fluorochromes calcein and alizarin was performed. In implants placed mesially in the tibiofemoral joint, biomechanical analysis was performed by means of a removal torque (N/cm). The tibias with the implants located distally to the joint were submitted for analysis by confocal laser microscopy (mineral apposition rate) and for histometric analysis by bone contact implant (%BIC) and newly formed bone area (%NBA). (3) Results: The SEM showed differences between the surfaces. The biomechanical analysis revealed significant differences in removal torque values between the MSs and LHSs over a 2-week period. Over a 4-week period, both the LSs and LHSs demonstrated removal torque values statistically higher than the MSs. BIC of the LHS implants were statistically superior to MS at the 2-week period and LHS and LS surfaces were statistically superior to MS at the 4-week period. Statistical analysis of the NBA of the implants showed difference between the LHS and MS in the period of 2 weeks. (4) Conclusions: The modifications of the LSs and LHSs provided important physicochemical modifications that favored the deposition of bone tissue on the surface of the implants.

20.
Article in English | MEDLINE | ID: mdl-39063448

ABSTRACT

This study was carried out in the district of Taquaral de Minas, in the municipality of Itinga, located in Jequitinhonha Valley, state of Minas Gerais, which is considered one of the largest yolk-producing regions in Brazil. Miners in gem extraction areas are prone to severe oxidative damage due to their increased exposure to toxic metals, as well as chemical, physical, and biological agents, resulting in diseases such as silicosis. Thus, this work aimed to evaluate occupational exposure in prospectors through biomonitoring techniques using a variety of biomarkers for oxidative stress, genotoxicity, and mutagenicity. Twenty-two miners and seventeen workers who were not occupationally exposed were recruited, totaling thirty-nine participants. The study was approved by the Research Ethics Committee of the Federal University of the Jequitinhonha and Mucuri Valleys. In this study, the levels of total peroxides, catalase activity, and microelements in plasma were evaluated. Additionally, environmental analysis was carried out through the Ames and Allium cepa tests. The results of the lipoperoxidation assessment were significant, with increased frequencies in exposed individuals compared to controls (p < 0.05), as determined by the Mann-Whitney test. Micronutrients in the blood showed lower concentrations in the group exposed to Fe and Se than in individuals not exposed to these elements. The results of the Ames test and Allium cepa test were statistically significant compared to the controls (p < 0.05), as determined by the Mann-Whitney test for genotoxicity and cytotoxicity. Thus, the results of the present study indicate possible environmental contamination and a potential risk to the health of miners, which suggests that further studies are important in the region.


Subject(s)
Biomarkers , Mining , Occupational Exposure , Oxidative Stress , Humans , Brazil , Occupational Exposure/analysis , Occupational Exposure/adverse effects , Adult , Biomarkers/blood , Male , Middle Aged , Biological Monitoring , Bertholletia/chemistry , Mutagenicity Tests , DNA Damage
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