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1.
BMC Neurol ; 24(1): 250, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039441

RESUMO

BACKGROUND: Diagnosis of primary diffuse large B-cell lymphoma of the central nervous system (PCNSL) is challenging and often delayed. MRI imaging, CSF cytology and flow cytometry have a low sensitivity and even brain biopsies can be misleading. We report three cases of PCNSL with various clinical presentation and radiological findings where the diagnosis was suggested by novel CSF biomarkers and subsequently confirmed by brain biopsy or autopsy. CASE PRESENTATIONS: The first case is a 79-year-old man with severe neurocognitive dysfunction and static ataxia evolving over 5 months. Brain MRI revealed a nodular ventriculitis. An open brain biopsy was inconclusive. The second case is a 60-year-old woman with progressive sensory symptoms in all four limbs, evolving over 1 year. Brain and spinal MRI revealed asymmetric T2 hyperintensities of the corpus callosum, corona radiata and corticospinal tracts. The third case is a 72-year-old man recently diagnosed with primary vitreoretinal lymphoma of the right eye. A follow-up brain MRI performed 4 months after symptom onset revealed a T2 hyperintense fronto-sagittal lesion, with gadolinium uptake and perilesional edema. In all three cases, CSF flow cytometry and cytology were negative. Mutation analysis on the CSF (either by digital PCR or by next generation sequencing) identified the MYD88 L265P hotspot mutation in all three cases. A B-cell clonality study, performed in case 1 and 2, identified a monoclonal rearrangement of the immunoglobulin light chain lambda (IGL) and kappa (IGK) gene. CSF CXCL-13 and IL-10 levels were high in all three cases, and IL-10/IL-6 ratio was high in two. Diagnosis of PCNSL was later confirmed by autopsy in case 1, and by brain biopsy in case 2 and 3. CONCLUSIONS: Taken together, 5 CSF biomarkers (IL-10, IL-10/IL-6 ratio, CXCL13, MYD88 mutation and monoclonal IG gene rearrangements) were strongly indicative of a PCNSL. Using innovative CSF biomarkers can be sensitive and complementary to traditional CSF analysis and brain biopsy in the diagnosis of PCNSL, potentially allowing for earlier diagnosis and treatment.


Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Masculino , Idoso , Linfoma Difuso de Grandes Células B/líquido cefalorraquidiano , Linfoma Difuso de Grandes Células B/diagnóstico , Pessoa de Meia-Idade , Feminino , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/diagnóstico por imagem , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/patologia , Biomarcadores Tumorais/líquido cefalorraquidiano , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética
2.
Antimicrob Resist Infect Control ; 13(1): 73, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38971822

RESUMO

The implementation of isolation precautions for patients with suspected Coronavirus Disease 2019 (COVID-19) and pending test results is resource intensive. Due to the limited availability of single-bed rooms at our institution, we isolated patients with suspected COVID-19 together with patients without suspected COVID-19 on-site in multiple-bed rooms until SARS-CoV-2-test results were available. We evaluated the likelihood of SARS-CoV-2 transmission to individuals sharing the room with patients isolated on-site. This observational study was performed at the University Hospital Basel, Switzerland, from 03/20 - 11/20. Secondary attack rates were compared between patients hospitalized in multiple-bed rooms and exposed to individuals subjected to on-site isolation precautions (on-site isolation group), and patients exposed to individuals initially not identified as having COVID-19, and not placed under isolation precautions until the diagnosis was suspected (control group). Transmission events were confirmed by whole-genome sequencing. Among 1,218 patients with suspected COVID-19, 67 (5.5%) tested positive for SARS-CoV-2. Of these, 21 were isolated on-site potentially exposing 27 patients sharing the same room. Median contact time was 12 h (interquartile range 7-18 h). SARS-CoV-2 transmission was identified in none of the patients in the on-site isolation group vs. 10/63 (15.9%) in the control group (p = 0.03). Isolation on-site of suspected COVID-19-patients in multiple-bed rooms avoided single-room occupancy and subsequent in-hospital relocation for many patients without confirmed SARS-CoV-2-infection. The absence of secondary transmission among the exposed patients in the on-site isolation group allows for assessment of the risk/benefit ratio of this strategy given the limitation of a small sample size.


Assuntos
COVID-19 , Isolamento de Pacientes , Quartos de Pacientes , SARS-CoV-2 , Humanos , COVID-19/transmissão , COVID-19/epidemiologia , COVID-19/diagnóstico , Feminino , Masculino , Suíça/epidemiologia , Pessoa de Meia-Idade , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação , Idoso , Adulto , Idoso de 80 Anos ou mais , Hospitais Universitários
3.
Clin Ophthalmol ; 18: 1921-1932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978835

RESUMO

Purpose: Any new intraocular lens (IOL) on the market claims to outperform competitors. We aimed to estimate the modulation transfer function (MTF) for different defocus of a novel refractive enhanced depth of focus (EDoF) IOL and the simulated visual acuity over this range of vision. Further, we analyzed the wavefront pattern produced by this IOL to reveal the function of the IOL's optics. Methods: For the novel TECNIS® PureSee® (ZEN00V) IOL, through frequency and through focus MTF were recorded on the optical bench (ISO-2 Cornea 0.28 µm, 546 nm). MTFa and the simulated visual acuity were calculated for different defocus. Apertures of 3 mm and 4.5 mm were applied. Higher order aberrations of the IOLs' optics were recorded and analyzed. Results: PureSee® IOL demonstrated a considerable depth of focus of about 1.7 D at the spectacle plane and a continuous simulated visual acuity over this range of defocus. For the 4.5 mm aperture, near focus depth was reduced, yet far distance MTF was even better. Higher order aberrations revealed increased primary and secondary spherical aberrations. Conclusion: Optical bench results suggest that the new ZEN00V matches the clinical criteria of an EDoF IOL by an increased range of vision and is far distance dominant for an enlarged pupil. This behaviour seems to be due to subtle power changes in the central optics that produce a complex modification of wavefront.

4.
J Avian Med Surg ; 38(2): 98-107, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38980819

RESUMO

The objective of this study was to establish the pharmacokinetics of a single oral dose of trazodone in the Hispaniolan Amazon parrot (Amazona ventralis). Trazodone is a selective serotonin antagonist and reuptake inhibitor used commonly in both human and veterinary medicine as an antidepressant behavioral modification medicine. A single oral dose of compounded trazodone hydrochloride solution (20 mg/mL) at 50 mg/kg was administered to a total of 7 healthy adult Hispaniolan Amazon parrots. The 7 healthy adult parrots ranged in age from 10 to 15 years and weighed 228 to 323g. Blood was collected at baseline (2 weeks before study) and at 1, 2, 4, 6, 10, and 14 hours post-drug administration. Plasma concentrations of both trazodone and its active metabolite m-chlorophenylpiperazine (mCPP) were measured via liquid chromatography tandem mass spectrometry. Noncompartmental pharmacokinetic analysis was completed. The half-life (t1/2) ± SD of trazodone for the Hispaniolan parrots was 1.89 ± 0.49 hours, and the t1/2 ± SD of mCPP metabolite was 1.9 ± 0.55 hours. Maximum serum drug concentrations, or Cmax (ng/mL), were 738.3 ± 285.3 for trazodone. Times to achieve Cmax (hours) for trazadone and the mCPP metabolite were 1 hour and 2 hours postdosing, respectively. While this study did not establish the behavioral effects of trazodone, no adverse side effects were observed throughout the 48-hour period following drug administration and blood collection. Our results indicate that the oral administration of a 50-mg/kg single dose of trazodone to Hispaniolan parrots may be considered a safe dose. Plasma concentrations are comparable to previously published values in humans, dogs, horses, and pigeons (Columba livia domestica) for up to 14 hours following dosing. This study indicates that further studies are needed to establish the pharmacodynamics and the efficacy of trazodone in the medical management of behavioral problems in psittacine species.


Assuntos
Amazona , Trazodona , Animais , Trazodona/farmacocinética , Trazodona/administração & dosagem , Trazodona/sangue , Amazona/sangue , Meia-Vida , Masculino , Área Sob a Curva , Inibidores Seletivos de Recaptação de Serotonina/farmacocinética , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/sangue , Feminino , Administração Oral
5.
Geroscience ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38992336

RESUMO

Early nutrition has significant effects on physiological outcomes during adult life. We have analysed the effect of maternal α-casein (CSN1S1) deficiency on the physiological fate of dams and their offspring. α-casein deficiency reduces maternal milk protein concentration by more than 50% and attenuates the growth of pups to 27% (p < 0.001) of controls at the point of weaning. This is associated with a permanent reduction in adult body weight (- 31% at 25 weeks). Offspring nursed by α-casein deficient dams showed a significantly increased lifespan (+ 20%, χ2: 10.6; p = 0.001). Liver transcriptome analysis of offspring nursed by α-casein deficient dams at weaning revealed gene expression patterns similar to those found in dwarf mice (reduced expression of somatotropic axis signalling genes, increased expression of xenobiotic metabolism genes). In adult mice, the expression of somatotropic axis genes returned to control levels. This demonstrates that, in contrast to dwarf mice, attenuation of the GH-IGF signalling axis in offspring nursed by α-casein deficient dams is transient, while the changes in body size and lifespan are permanent. Offspring nursed by α-casein deficient dams showed permanent changes in body composition. Absolute and relative adipose tissue weights (p < 0.05), the percentage of body fat (p < 0.001) as well as adipocyte size in epididymal white adipose tissue are all reduced. Serum leptin levels were 25% of those found in control mice (p < 0.001). Liver lipid content and lipid composition were significantly altered in response to postnatal nutrition. This demonstrates the nutrition in early life programmes adult lipid metabolism, body composition and lifespan.

6.
Angew Chem Int Ed Engl ; : e202409781, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38979659

RESUMO

Most metathesis polymers based on norbornene derivatives carry a vinyl end group. Here we show that these vinyl end groups readily undergo a degenerative exchange of the terminal methylene unit in the presence of sub-stoichiometric amounts of a propagating metathesis polymer carrying a Grubbs ruthenium complex. We show that this degenerative exchange can be exploited in synthesizing ROMP polymers in a catalytic living fashion. Chain transfer agents based on styrene, or monosubstituted conjugated 1,3 diene derivatives are used as initiating sites for the catalytic living polymerization. Suitable derivatives of these chain transfer agents not only allow the linear living growth of polymers but also the synthesis of block copolymers from macro-initiators or star polymers from multi-functional chain transfer agents. This reversible exchange mechanism offers a cheaper, greener, and more sustainable alternative for the synthesis of living ROMP polymers compared to the classical synthetic route.

7.
Lasers Med Sci ; 39(1): 167, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954050

RESUMO

Nowadays, lasers are used in various medical fields. Ophthalmology was the first medical specialty to utilize lasers in patient treatment and still remains the leading medical field that uses laser energy for both therapeutic and diagnostic purposes. The neodymium: yttrium-aluminum-garnet (Nd: YAG) laser is one of the most common lasers used in ophthalmology. It is a solid-state laser with a wavelength of 1064 nm that works on the principle of photodisruption. Since its introduction in ophthalmology over 40 years ago, it has found various applications, mainly for procedures where cutting or disruption of ocular tissue is required. Compared to surgical alternatives, the use of Nd: YAG lasers on ocular tissue is minimally invasive. In this review, we focus on the two most common ophthalmic applications of Nd: YAG laser - laser peripheral iridotomy and posterior capsulotomy. The history of the techniques, current trends, potential complications, and the prognosis for future use is discussed.


Assuntos
Lasers de Estado Sólido , Humanos , Lasers de Estado Sólido/uso terapêutico , Terapia a Laser/métodos , Terapia a Laser/instrumentação , Capsulotomia Posterior/métodos , Iridectomia/métodos , Oftalmologia , Iris/cirurgia
8.
Seizure ; 120: 1-4, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38875892

RESUMO

PURPOSE: Status epilepticus (SE) represents a neurological emergency with significant morbidity and mortality. SE in patients with primary brain tumors received only limited attention to date; detailed analysis of treatment flow is lacking, especially as compared to other SE causes. This study aims to describe the frequency and treatment flow of tumor-related SE and compare it to other SE etiologies. METHODS: Retrospective cohort study based on an institutional SE registry (SERCH) comprising adult SE (excluding post-anoxic causes), treated between January 2013 and December 2022, comparing SE management, frequency of refractory SE, and clinical outcome, among four patients' groups stratified by SE etiology: Non-neoplastic, Gliomas, Brain metastases, Other brain tumors. RESULTS: We analyzed 961 episodes in 831 patients (Non-neoplastic: 649, Gliomas: 85, Metastases: 77, Other brain tumors: 20). Although tumor-patients presented more often with focal episodes and less consciousness impairment than non-neoplastic patients, administration of benzodiazepines as first-line treatment (>75% across all groups), and utilization of second-line ASM were similar across groups. Treatment adequacy was marginally higher in glioma patients compared to the non-neoplastic population (p: 0.049), while refractory SE was comparable in all groups (p: 0.269). No significant differences in clinical outcomes were observed (mortality: non-neoplastic (89/649, 13.7%), glioma (8/85, 9.4%), metastases (14/77, 18.2%), other tumors (5/20, 25.0%), p: 0.198; non-neoplastic vs. glioma, p: 0.271) CONCLUSION: Tumor-associated SE represents 1/5 of all SE episodes, and is managed similarly to other SE causes. Treatment responsiveness and short-term clinical outcomes also exhibit comparable results.

10.
J Long Term Eff Med Implants ; 34(4): 71-81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38842235

RESUMO

A thorough literature search was done in PubMed and Google Scholar as well as in physical books in libraries to summarize the literature on the history and evolution of medicine and orthopedics. The philosophical ideas that emerged in ancient Greece served as a foundation for the development of medicine. In the 5th century BC, the schools of Knidos and Kos emerged as influential centers for the development of medical thinking. The field of orthopedics can be traced back to early human civilizations. Ancient Egyptians perpetuated the tradition of employing splinting techniques. Hippocrates provided insights for the diagnosis, correction and treatment of many musculoskeletal entities. The field of medicine experienced a period of limited advancement during the Middle Ages. The Renaissance provided for the foundation of modern orthopedics and important contributions to the understanding and implementation of antisepsis. The discovery of x-ray and advancements in infection control and anesthesia have shown substantial progress in the domain of orthopedics and have contributed to the development of orthopedic subspecialization. Orthopedic surgery holds a historical lineage deeply entrenched in ancient practices and early human civilizations. Physicians specializing in orthopedics should be aware of the historical origins of their discipline and continue to evolve through further subspecialization and enhanced research.


Assuntos
Ortopedia , História Antiga , Humanos , História do Século XVI , História Medieval , Ortopedia/história , História do Século XVII , História do Século XX , História do Século XV , História do Século XIX , História do Século XVIII , História do Século XXI
11.
Artigo em Inglês | MEDLINE | ID: mdl-38836904

RESUMO

PURPOSE: Immune checkpoint inhibitors (ICIs) have improved the prognosis of patients with cancer, such as melanoma, renal cell carcinoma, head and neck cancer, non-small cell lung cancer (NSCLC), and urothelial carcinoma. The extension of life expectancy has led to an increased incidence of bone metastases (BM) among patients with cancer. BM result in skeletal-related events, including severe pain, pathological fractures, and nerve palsy. Surgery is typically required for the treatment of BM in patients with an impending fracture; however, it may be avoided in those who respond to ICIs. We systematically reviewed studies analyzing BM responses to treatment with ICIs. METHODS: This study was conducted in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses 2020 statement and registered in the UMIN Clinical Trials Registry (ID: UMIN000053707). Studies reporting response rates based on the Response Evaluation Criteria in Solid Tumors (RECIST) or the MD Anderson Cancer Center (MDA) criteria specific for BM in patients treated with ICIs were included; reports of fewer than five cases and review articles were excluded. Studies involving humans, published in English and Japanese, were searched. The PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched. Ultimately, nine studies were analyzed. The Risk of Bias Assessment tool for Non-randomized Studies was used to assess the quality of studies. RESULTS: Based on the MDA criteria, complete response (CR) or partial response (PR) was observed in 44-78% and 62% patients treated with ICIs plus denosumab for NSCLC and melanoma, respectively. According to the RECIST, CR or PR was recorded in 5% and 7-28% of patients treated with ICIs for renal cell carcinoma and urothelial carcinoma, respectively. CONCLUSION: Although response rates to ICIs for BM are poor, patients treated with ICI plus denosumab for bone metastases with impending fractures from NSCLC and melanoma are likely to avoid surgery to prevent fractures.

12.
SICOT J ; 10: 24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38847648

RESUMO

BACKGROUND: Periprosthetic joint infection (PJI) remains a major complication following total joint arthroplasties (TJA), significantly affecting patient outcomes and healthcare costs. Despite advances in diagnostic techniques, challenges persist in accurately diagnosing PJI, underscoring the need for effective point-of-care testing (POCT). METHODS: This review examines the current literature and latest developments in POCT for diagnosing PJI, focusing on biomarkers such as alpha-defensin, leukocyte esterase, calprotectin, and C-reactive protein (CRP). Criteria from various societies like the Musculoskeletal Infection Society, Infectious Diseases Society of America, and the International Consensus Meeting were compared to evaluate the effectiveness of these biomarkers in a point-of-care setting. RESULTS: POCT provides rapid results essential for the timely management of PJI, with alpha-defensin and leukocyte esterase showing high specificity and sensitivity. Recent advancements have introduced novel biomarkers like calprotectin, which demonstrate high diagnostic accuracy. However, challenges such as the variability in test performance and the need for validation under different clinical scenarios remain. DISCUSSION: While POCT for PJI shows promising results, their integration into clinical practice requires standardized protocols and further validation. The evolution of these diagnostic tools offers a potential shift toward more personalized and immediate care, potentially improving outcomes for patients undergoing TJA.

13.
JAMA ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884982

RESUMO

Importance: Preoperative skin antisepsis is an established procedure to prevent surgical site infections (SSIs). The choice of antiseptic agent, povidone iodine or chlorhexidine gluconate, remains debated. Objective: To determine whether povidone iodine in alcohol is noninferior to chlorhexidine gluconate in alcohol to prevent SSIs after cardiac or abdominal surgery. Design, Setting, and Participants: Multicenter, cluster-randomized, investigator-masked, crossover, noninferiority trial; 4403 patients undergoing cardiac or abdominal surgery in 3 tertiary care hospitals in Switzerland between September 2018 and March 2020 were assessed and 3360 patients were enrolled (cardiac, n = 2187 [65%]; abdominal, n = 1173 [35%]). The last follow-up was on July 1, 2020. Interventions: Over 18 consecutive months, study sites were randomly assigned each month to either use povidone iodine or chlorhexidine gluconate, each formulated in alcohol. Disinfectants and skin application processes were standardized and followed published protocols. Main Outcomes and Measures: Primary outcome was SSI within 30 days after abdominal surgery and within 1 year after cardiac surgery, using definitions from the US Centers for Disease Control and Prevention's National Healthcare Safety Network. A noninferiority margin of 2.5% was used. Secondary outcomes included SSIs stratified by depth of infection and type of surgery. Results: A total of 1598 patients (26 cluster periods) were randomly assigned to receive povidone iodine vs 1762 patients (26 cluster periods) to chlorhexidine gluconate. Mean (SD) age of patients was 65.0 years (39.0-79.0) in the povidone iodine group and 65.0 years (41.0-78.0) in the chlorhexidine gluconate group. Patients were 32.7% and 33.9% female in the povidone iodine and chlorhexidine gluconate groups, respectively. SSIs were identified in 80 patients (5.1%) in the povidone iodine group vs 97 (5.5%) in the chlorhexidine gluconate group, a difference of 0.4% (95% CI, -1.1% to 2.0%) with the lower limit of the CI not exceeding the predefined noninferiority margin of -2.5%; results were similar when corrected for clustering. The unadjusted relative risk for povidone iodine vs chlorhexidine gluconate was 0.92 (95% CI, 0.69-1.23). Nonsignificant differences were observed following stratification by type of surgical procedure. In cardiac surgery, SSIs were present in 4.2% of patients with povidone iodine vs 3.3% with chlorhexidine gluconate (relative risk, 1.26 [95% CI, 0.82-1.94]); in abdominal surgery, SSIs were present in 6.8% with povidone iodine vs 9.9% with chlorhexidine gluconate (relative risk, 0.69 [95% CI, 0.46-1.02]). Conclusions and Relevance: Povidone iodine in alcohol as preoperative skin antisepsis was noninferior to chlorhexidine gluconate in alcohol in preventing SSIs after cardiac or abdominal surgery. Trial Registration: ClinicalTrials.gov Identifier: NCT03685604.

14.
Int J Mol Sci ; 25(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38928106

RESUMO

Lifestyle interventions can prevent type 2 diabetes (T2DM). However, some individuals do not experience anticipated improvements despite weight loss. Biomarkers to identify such individuals at early stages are lacking. Insulin-like growth factor 1 (IGF- 1) and Insulin-like growth factor binding protein 1(IGFBP-1) were shown to predict T2DM onset in prediabetes. We assessed whether these markers also predict the success of lifestyle interventions, thereby possibly guiding personalized strategies. We analyzed the fasting serum levels of IGF-1, IGFBP-1, and Insulin-like growth factor binding protein 2 (IGFBP-2) in relation to changes in metabolic and anthropometric parameters, including intrahepatic lipids (IHLs) and visceral adipose tissue (VAT) volume, measured by magnetic resonance imaging (MRI), in 345 participants with a high risk for prediabetes (54% female; aged 36-80 years). Participants were enrolled in three randomized dietary intervention trials and assessed both at baseline and one year post-intervention. Statistical analyses were performed using IBM SPSS Statistics (version 28), and significance was set at p < 0.05. Within the 1-year intervention, overall significant improvements were observed. Stratifying individuals by baseline IGF-1 and IGFBP-1 percentiles revealed significant differences: higher IGF-1 levels were associated with more favorable changes compared to lower levels, especially in VAT and IHL. Lower baseline IGFBP-1 levels were associated with greater improvements, especially in IHL and 2 h glucose. Higher bioactive IGF-1 levels might predict better metabolic outcomes following lifestyle interventions in prediabetes, potentially serving as biomarkers for personalized interventions.


Assuntos
Biomarcadores , Diabetes Mellitus Tipo 2 , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Fator de Crescimento Insulin-Like I , Estilo de Vida , Humanos , Feminino , Masculino , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Pessoa de Meia-Idade , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/análise , Idoso , Adulto , Diabetes Mellitus Tipo 2/sangue , Biomarcadores/sangue , Idoso de 80 Anos ou mais , Estado Pré-Diabético/sangue , Estado Pré-Diabético/terapia , Gordura Intra-Abdominal/metabolismo , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue
16.
Comput Methods Programs Biomed ; 254: 108269, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38861877

RESUMO

BACKGROUND AND OBJECTIVE: Degenerative meniscus tissue has been associated with a lower elastic modulus and can lead to the development of arthrosis. Safe intraoperative measurement of in vivo elastic modulus of the human meniscus could contribute to a better understanding of meniscus health, and for developing surgical simulators where novice surgeons can learn to distinguish healthy from degenerative meniscus tissue. Such measurement can also support intraoperative decision-making by providing a quantitative measure of the meniscus health condition. The objective of this study is to demonstrate a method for intraoperative identification of meniscus elastic modulus during arthroscopic probing using an adaptive observer method. METHODS: Ex vivo arthroscopic examinations were performed on five cadaveric knees to estimate the elastic modulus of the anterior, mid-body, and posterior regions of lateral and medial menisci. Real-time intraoperative force-displacement data was obtained and utilized for modulus estimation through an adaptive observer method. For the validation of arthroscopic elastic moduli, an inverse parameter identification approach using optimization, based on biomechanical indentation tests and finite element analyses, was employed. Experimental force-displacement data in various anatomical locations were measured through indentation. An iterative optimization algorithm was employed to optimize elastic moduli and Poisson's ratios by comparing experimental force values at maximum displacement with the corresponding force values from linear elastic region-specific finite element models. Finally, the estimated elastic modulus values obtained from ex vivo arthroscopy were compared against optimized values using a paired t-test. RESULTS: The elastic moduli obtained from ex vivo arthroscopy and optimization showcased subject specificity in material properties. Additionally, the results emphasized anatomical and regional specificity within the menisci. The anterior region of the medial menisci exhibited the highest elastic modulus among the anatomical locations studied (9.97±3.20MPa from arthroscopy and 5.05±1.97MPa from finite element-based inverse parameter identification). The paired t-test results indicated no statistically significant difference between the elastic moduli obtained from arthroscopy and inverse parameter identification, suggesting the feasibility of stiffness estimation using arthroscopic examination. CONCLUSIONS: This study has demonstrated the feasibility of intraoperative identification of patient-specific elastic modulus for meniscus tissue during arthroscopy.


Assuntos
Artroscopia , Módulo de Elasticidade , Menisco , Humanos , Menisco/cirurgia , Análise de Elementos Finitos , Fenômenos Biomecânicos , Meniscos Tibiais/cirurgia , Meniscos Tibiais/diagnóstico por imagem , Algoritmos , Cadáver , Masculino
17.
Ophthalmic Res ; 67(1): 292-300, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718759

RESUMO

INTRODUCTION: Cataract extraction is the most frequently performed ophthalmological procedure worldwide. Posterior capsule opacification remains the most common consequence after cataract surgery and can lead to deterioration of the visual performance with cloudy, blurred vision and halo, glare effects. Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy is the gold standard treatment and a very effective, safe and fast procedure in removing the cloudy posterior capsule. Damaging the intraocular lens (IOL) during the treatment may occur due to wrong focus of the laser beam. These YAG-pits may lead to a permanent impairment of the visual quality. METHODS: In an experimental study, we intentionally induced YAG pits in hydrophilic and hydrophobic acrylic IOLs using a photodisruption laser with 2.6 mJ. This experimental study established a novel 3D imaging method using correlative X-ray and scanning electron microscopy (SEM) to characterize these damages. By integrating the information obtained from both X-ray microscopy and SEM, a comprehensive picture of the materials structure and performance could be established. RESULTS: It could be revealed that although the exact same energies were used to all samples, the observed defects in the tested lenses showed severe differences in shape and depth. While YAG pits in hydrophilic samples range from 100 to 180 µm depth with a round shape tip, very sharp tipped defects up to 250 µm in depth were found in hydrophobic samples. In all samples, particles/fragments of the IOL material were found on the surface that were blasted out as a result of the laser shelling. CONCLUSION: Defects in hydrophilic and hydrophobic acrylic materials differ. Material particles can detach from the IOL and were found on the surface of the samples. The results of the laboratory study illustrate the importance of a precise and careful approach to Nd:YAG capsulotomy in order to avoid permanent damage to the IOL. The use of an appropriate contact glass and posterior offset setting to increase safety should be carried out routinely.


Assuntos
Lasers de Estado Sólido , Lentes Intraoculares , Lasers de Estado Sólido/uso terapêutico , Imageamento Tridimensional , Microscopia Eletrônica de Varredura/métodos , Humanos
18.
J Trace Elem Med Biol ; 84: 127462, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38701651

RESUMO

Aging is associated with a decline in physiological functions and an increased risk of age-related diseases, emphasizing the importance of identifying dietary strategies for healthy aging. Minerals play a crucial role in maintaining optimal health during aging, making them relevant targets for investigation. Therefore, we aimed to analyze the effect of different dietary pattern on mineral status in the elderly. We included 502 individuals aged 50-80 years in a 36-month randomized controlled trial (RCT) (NutriAct study). This article focuses on the results within the two-year intervention period. NutriAct is not a mineral-modulating-targeted intervention study, rather examining nutrition in the context of healthy aging in general. However, mineral status might be affected in an incidental manner. Participants were assigned to either NutriAct dietary pattern (proportionate intake of total energy consumption (%E) of 35-45 %E carbohydrates, 35-40 %E fats, and 15-25 %E protein) or the German Nutrition Society (DGE) dietary pattern (proportionate intake of total energy consumption (%E) of 55 %E carbohydrates, 30 %E fats, and 15 %E protein), differing in the composition of macronutrients. Data from 368 participants regarding dietary intake (energy, calcium, magnesium, iron, and zinc) and serum mineral concentrations of calcium, magnesium, iron, copper, zinc, selenium, iodine, and manganese, free zinc, and selenoprotein P were analyzed at baseline, as well as after 12 and 24 months to gain comprehensive insight into the characteristics of the mineral status. Additionally, inflammatory status - sensitive to changes in mineral status - was assessed by measurement of C-reactive protein and interleukin-6. At baseline, inadequate dietary mineral intake and low serum concentrations of zinc and selenium were observed in both dietary patterns. Throughout two years, serum zinc concentrations decreased, while an increase of serum selenium, manganese and magnesium concentrations was observable, likely influenced by both dietary interventions. No significant changes were observed for serum calcium, iron, copper, or iodine concentrations. In conclusion, long-term dietary interventions can influence serum mineral concentrations in a middle-aged population. Our findings provide valuable insights into the associations between dietary habits, mineral status, and disease, contributing to dietary strategies for healthy aging.


Assuntos
Dieta , Envelhecimento Saudável , Minerais , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alemanha , Envelhecimento Saudável/sangue , Minerais/sangue , Estado Nutricional
19.
Cancers (Basel) ; 16(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38730736

RESUMO

BACKGROUND: Awake craniotomy (AC) is recommended for the resection of tumors in eloquent areas. It is traditionally performed under monitored anesthesia care (MAC), which relies on hypnotics and opioids. Hypnosis-assisted AC (HAAC) is an emerging technique that aims to provide psychological support while reducing the need for pharmacological sedation and analgesia. We aimed to compare the characteristics and outcomes of patients who underwent AC under HAAC or MAC. METHODS: We retrospectively analyzed the clinical, anesthetic, surgical, and neuropsychological data of patients who underwent awake surgical resection of eloquent brain tumors under HAAC or MAC. We used Mann-Whitney U tests, Wilcoxon signed-rank tests, and repeated-measures analyses of variance to identify statistically significant differences at the 0.05 level. RESULTS: A total of 22 patients were analyzed, 14 in the HAAC group and 8 in the MAC group. Demographic, radiological, and surgical characteristics as well as postoperative outcomes were similar. Patients in the HAAC group received less remifentanil (p = 0.047) and propofol (p = 0.002), but more dexmedetomidine (p = 0.025). None of them received ketamine as a rescue analgesic. Although patients in the HAAC group experienced higher levels of perioperative pain (p < 0.05), they reported decreasing stress levels (p = 0.04) and greater levels of satisfaction (p = 0.02). CONCLUSION: HAAC is a safe alternative to MAC as it reduces perioperative stress and increases overall satisfaction. Further research is necessary to assess whether hypnosis is clinically beneficial.

20.
SICOT J ; 10: 19, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38819289

RESUMO

BACKGROUND: Peri-megaprosthetic joint infections (PJI) in tumor surgery are complex and challenging complications that significantly impact the outcomes of the patients. The occurrence of PJI poses a substantial threat to the success of these operations. This review aims to identify and summarize the risk factors associated with PJI in tumor surgery with megaprosthetic reconstruction as well as to determine the overall risk of PJI in limb salvage surgery. METHODS: A thorough examination of published literature, scrutinizing the incidence of PJI in tumor prostheses after limb salvage surgery was done. Research studies that documented the incidence of PJI in tumor patients who underwent limb salvage surgery, and explored the risk factors associated with the occurrence of PJI were deemed eligible. RESULTS: A total of 15 studies were included in the analysis and underwent comprehensive examination. After the exploration of key parameters, several significant risk factors for PJI concerning the type of implant coating, surgical site characteristics, patient demographics, and procedural factors were recorded. DISCUSSION: The findings underscore the need for a nuanced approach in managing tumor patients undergoing limb salvage surgery and megaprosthetic reconstruction, with emphasis on individualized risk assessments and individualized preventive strategies.

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