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1.
Europace ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39397761

RESUMO

Carotid sinus massage (CSM) as integral part of cardiovascular autonomic testing, is indicated in all patients > 40 years with syncope of unknown origin and suspected reflex mechanism. However, large practice variation exists in performing CSM which inevitably affects the positivity rate of the test and may result in an inaccurate diagnosis in patients with unexplained syncope. Even though CSM was introduced into medical practice more than 100 years ago, the method of performing CSM is still largely operator- and centre-dependent, while in many places the test has been entirely abandoned. Here we describe a standardized protocol on how to perform CSM, which basic monitoring equipment is necessary and why CSM is a safe procedure to perform. Our aim is to create an uniform approach to perform CSM. The new proposed algorithm, the Six Step Method includes: 1) Check history for exclusion CSM; 2) Turn head slightly contralaterally and posterior (see also explanatory video and poster provided as supplementary material; 3) Palpation to identify carotid sinus location; 4) Massage for 10 seconds; 5) Monitoring of blood pressure and heart rate to assess of the hemodynamic response type, and 6) Include time intervals between subsequent massages. CSM should be performed on both the left and right and in the supine and upright position. The recommended equipment to perform CSM consists of: 1) a tilt table in order to perform CSM in supine and standing position, 2) a continuous blood pressure monitor or cardiac monitor and 3) at least two persons.

2.
J Clin Med ; 13(19)2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39407773

RESUMO

Background/Objectives: Vascular aging can be assessed by arterial stiffness measured through pulse wave velocity (PWV). Increased PWV predicts arterial hypertension, cardiovascular events and all-cause mortality. Detection of early signs of vascular aging remains an unmet problem. To search for the most sensitive markers for the early increase in vascular stiffness in a healthy population. Methods: One-hundred and twenty healthy subjects were divided in three equal age groups: <30 years, 30-45 years and >45 years. Head-up tilt test (HUTT) protocol was applied, providing a standardized hydrostatic column height. PWV at the brachial-ankle artery site (baPWV) was measured using a multichannel sphygmomanometer ABI System 100 PWV in three positions: in the baseline horizontal (supine) position-baPWVb; during the head tilt-up with an individual angle of inclination-baPWVt; and when returning to supine. Results: The most sensitive marker of early stiffness increase in a healthy population is the relative orthostatic increase in baPWV, ΔbaPWV/baPWVb, where ΔbaPWV = baPWVt - baPWVb. The significance of differences in this parameter between the young and elderly groups reached p = 0.000075 and p = 0.000006, respectively. Conclusions: The proposed index ΔbaPWV/baPWVb can be considered as a promising sensitive early biomarker of vascular aging and as a potential effective indicator in cardiovascular prevention. A longitudinal cohort study is needed to confirm this assumption.

3.
BMC Ophthalmol ; 24(1): 459, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39428465

RESUMO

PURPOSE: To compare long-term intraocular lens (IOL) decentration and tilt following femtosecond laser-assisted cataract surgery (FLACS) and conventional surgery using swept-source anterior segment ocular coherence tomography (SS-ASOCT). METHODS: In this retrospective cross-sectional study, all patients underwent FLACS or conventional cataract surgery. Those with a minimum of 12-months follow-up since surgery were included. Patients with surgical complications were excluded. Demographics, preoperative ocular measurements (axial length, anterior chamber depth), and postoperative measurements [corrected distance visual acuity (CDVA), autorefraction, keratometry, IOL type] were collected. Postoperative IOL tilt and decentration were compared using SS-ASOCT between patients with FLACS and conventional cataract surgery. Subgroup analysis was conducted to analyze tilt and decentration by haptic type (single-piece vs. three-piece). RESULTS: A total of 188 eyes were included [110 (58.5%) in the FLACS group and 78 (41.5%) in the conventional group]. No differences were observed between the FLACS and conventional groups regarding preoperative parameters. FLACS resulted in less IOL decentration compared to conventional cataract surgery (170 µm vs. 240 µm, p = 0.002). No statistically significant differences were observed between the FLACS and conventional groups in the magnitude and axis of IOL tilt. Both groups had a trend of IOL tilt toward the inferotemporal aspects. Moreover, no difference regarding postoperative CDVA, spherical equivalent, and keratometric astigmatism was observed. CONCLUSIONS: FLACS resulted in significantly better long-term IOL centration than conventional surgery with manual capsulotomy. No significant difference in IOL tilt or postoperative CDVA was observed between FLACS and conventional cataract surgery.


Assuntos
Migração do Implante de Lente Intraocular , Extração de Catarata , Terapia a Laser , Lentes Intraoculares , Acuidade Visual , Humanos , Estudos Retrospectivos , Feminino , Masculino , Idoso , Estudos Transversais , Acuidade Visual/fisiologia , Pessoa de Meia-Idade , Extração de Catarata/métodos , Migração do Implante de Lente Intraocular/fisiopatologia , Migração do Implante de Lente Intraocular/etiologia , Terapia a Laser/métodos , Tomografia de Coerência Óptica/métodos , Seguimentos , Implante de Lente Intraocular/métodos , Complicações Pós-Operatórias , Refração Ocular/fisiologia , Idoso de 80 Anos ou mais , Pseudofacia/fisiopatologia
4.
J Orthop Sci ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39366815

RESUMO

INTRODUCTION: Femoral neck fractures (FNFs) are common in elderly individuals. When minimally displaced, they are typically treated with internal fixation. Nonunion is a complication of internal fixation of FNF, that sometimes necessitates reoperation. Radiographic parameters, including the Pauwels angle and posterior tilt angle, are risk factors for nonunion. However, these parameters are assessed solely in a two-dimensional context. We developed a novel radiographic parameter named the "Kindex." This multicenter investigation aimed to identify risk factors for nonunion following FNF fixation and evaluate the validity of this index. METHODS: This retrospective multicenter study collected data from 939 FNF patients who underwent internal fixation between 2016 and 2020 at 11 facilities (TRON group). The following exclusion criteria were applied: age <65, insufficient data, and Garden Stage III or IV fracture. Patient data, including age, sex, BMI, ASA classification, alcohol and smoking history, and comorbidities, were recorded. Radiographic measurements of the Pauwels angle and posterior tilt angle at the time of injury were used to calculate the Kindex. Correlations between the Pauwels angle, posterior tilt angle, Kindex, and nonunion were evaluated. A multivariate logistic regression analysis was performed to investigate independent risk factors for nonunion. A receiver operating characteristic (ROC) analysis was performed to determine the cutoff value of the Kindex, and the area under the curve (AUC) was calculated. RESULTS: The study included 594 patients (males, n = 151; females, n = 443; average age, 80.9 years). Nonunion was observed in 13 cases (2.2 %). While the Pauwels angle and posterior tilt angle did not show significant correlations, the Kindex exhibited strong correlations with both parameters. In the multivariate analysis, the Kindex and renal impairment were independent risk factors for nonunion (Kindex: OR 1.06, p = 0.015; renal impairment: OR 1.48, p = 0.021). In the ROC analysis, a Kindex of 50 was identified as the optimal cutoff value (AUC 0.72). CONCLUSION: The nonunion rate after internal fixation of FNF was 2.2 %. Renal impairment and the Kindex were identified as independent risk factors. The Kindex at the time of injury may serve as a novel radiographic parameter to consider when evaluating the need for internal fixation in FNF cases.

5.
Prim Health Care Res Dev ; 25: e53, 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39434594

RESUMO

AIM: The goals of this investigation were to 1) identify and measure exposures inside homes of individuals with chemical intolerance (CI), 2) provide guidance for reducing these exposures, and 3) determine whether our environmental house calls (EHCs) intervention could reduce both symptoms and measured levels of indoor air contaminants. BACKGROUND: CI is an international public health and clinical concern, but few resources are available to address patients' often disabling symptoms. Numerous studies show that levels of indoor air pollutants can be two to five (or more) times higher than outdoor levels. Fragranced consumer products, including cleaning supplies, air fresheners, and personal care products, are symptom triggers commonly reported by susceptible individuals. METHODS: A team of professionals trained and led by a physician/industrial hygienist and a certified indoor air quality specialist conducted a series of 5 structured EHCs in 37 homes of patients reporting CI. RESULTS: We report three case studies demonstrating that an appropriately structured home intervention can teach occupants how to reduce indoor air exposures and associated symptoms. Symptom improvement, documented using the Quick Environmental Exposure and Sensitivity Inventory Symptom Star, corresponded with the reduction of indoor air volatile organic compounds, most notably fragrances. These results provide a deeper dive into 3 of the 37 cases described previously in Perales et al. (2022). DISCUSSION: We address the long-standing dilemma that worldwide reports of fragrance sensitivity have not previously been confirmed by human or animal challenge studies. Our ancient immune systems' 'first responders', mast cells, which evolved 500 million years ago, can be sensitized by synthetic organic chemicals whose production and use have grown exponentially since World War II. We propose that these chemicals, which include now-ubiquitous fragrances, trigger mast cell degranulation and inflammatory mediator release in the olfactory-limbic tract, thus altering cerebral blood flow and impairing mood, memory, and concentration (often referred to as 'brain fog'). The time has come to translate these research findings into clinical and public health practice.


Assuntos
Poluição do Ar em Ambientes Fechados , Sensibilidade Química Múltipla , Humanos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Feminino , Masculino , Pessoa de Meia-Idade , Exposição Ambiental/efeitos adversos , Exposição Ambiental/prevenção & controle , Adulto , Idoso
6.
Eur Spine J ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39443372

RESUMO

OBJECTIVE: To propose a novel classification system for stratifying coronal curve patterns in congenital cervicothoracic scoliosis with hemivertebrae (CTS-HV). METHODS: Type A: regional cervicothoracic deformity only disturbing the balance of head-neck-shoulder complex; Type B: cervicothoracic deformity with significant trunk tilt to the convex side; Type C: cervicothoracic deformity with a significant compensatory thoracic curve. The reliability and reproducibility were assessed via the Kappa test. The differences among different subtypes in deformity parameters and bony structures were compared to identify the causative factors predisposing to different subtypes. RESULTS: 98 patients were classified into Type A (47 cases), Type B (31 cases), and Type C (20 cases). The Kappa test showed excellent reliability (Kappa value = 0.847) and reproducibility (Kappa value = 0.881). The proportions of Klippel-Feil syndrome in Types B (71.0%) and C (85.0%) were significantly higher than in Type A (46.8%; all P < 0.05). Type A (66.0%) and Type B (71.0%) predominantly had their hemivertebra (HV) at T3 or T4, while Type C (75%) mostly had HV at T1 or T2. Type B exhibited the most severe trunk tilt, head shift, neck tilt, head tilt, and coronal balance distance (all P < 0.05). Type C had the lowest T1 tilt and first rib angle despite the greatest cervicothoracic Cobb angle (all P < 0.05). CONCLUSIONS: This novel reliable classification allows a better understanding of structural diversity and different coronal compensatory mechanisms for the natural progression of CTS-HV. It can contribute to determining the individualized treatment strategy and standardizing academic communication for this rare clinical entity.

7.
Exp Physiol ; 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39447579

RESUMO

Postural fluid shifts may directly affect respiratory control via a complex interaction of baro- and chemo-reflexes, and cerebral blood flow. Few data exist concerning the steady state ventilatory responses during head-down tilt. We examined the cardiorespiratory responses during acute 50° head-down tilt (HDT) in 18 healthy subjects (mean [SD] age 27 [10] years). Protocol 1 (n = 8, two female) was 50° HDT from 60° head-up posture sustained for 10 min, while exposed to normoxia, normoxic hypercapnia (5% CO2), hypoxia (12% inspired O2) or hyperoxic hypercapnia (95% O2, 5% CO2). Protocol 2 (n = 10, four female) was 50° HDT from supine, sustained for 10 min, while breathing either medical air or normoxic hypercapnic (5% CO2) gas. Ventilation ( V ̇ E ${{\dot{V}}_E}$ , pneumotachograph), end-tidal O2 and CO2 concentration and blood pressure (Finapres) were measured continuously throughout each protocol. Middle cerebral artery blood flow velocity (MCAv; transcranial Doppler) was also measured during protocol 2. Ventilation increased significantly (P < 0.05) compared to baseline during HDT in both hyperoxic hypercapnia (protocol 1 by mean [SD] 139 [26]%) and normoxic hypercapnia (protocol 1 by mean [SD] 131 [21]% and protocol 2 by 129 [23]%), despite no change in P ETC O 2 ${{P}_{{\mathrm{ETC}}{{{\mathrm{O}}}_2}}}$ or P ET O 2 ${{P}_{{\mathrm{ET}}{{{\mathrm{O}}}_2}}}$ from baseline. No change in V ̇ E ${{\dot{V}}_E}$ was observed during HDT with medical air or hypoxia, and there was no significant change in MCAv during HDT compared to baseline. The absence of change in cerebral blood flow leads us to postulate that the augmented ventilatory response during steep HDT may involve mechanisms related to cerebral venous pressure and venous outflow.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39450918

RESUMO

Bifacial perovskite solar cells (Bi-PSCs) have attracted substantial attention within the photovoltaic (PV) community due to their potential for enhanced power generation, suitability for integration into building structures and applicability in multijunction PV systems. This study presents the fabrication of efficient Bi-PSCs and investigates their unique properties using various characterization techniques, including Lambertian reflection effects through tilt angle arrangements and bottom albedo illuminations. The control device achieved a maximum power conversion efficiency (PCE) of 17.46% under front-side 1 Sun AM1.5G illumination. A significant influence of ground Lambertian reflection is observed with tilt angle variations, resulting in an increase in PCE from 17.46% → 18.82% as the tilt angle reached 20°. Additionally, enhancing the rear-side albedo to 0.5 Sun yielded a maximum PCE of 26% with a bifaciality factor of ∼90% at a tilt angle of 20°. Consequently, the synergistic effect of 0.5 Sun albedo and a 20° angular light inclination led to the development of Bi-PSCs with an efficiency of 26.46%. SCAPS-1D simulations are further employed to validate the experimental Lambertian reflection effects. Moreover, the Bi-PSCs exhibited intrinsic self-encapsulation and chemical robustness (T80 for 2000 h in the N2 atmosphere). This study anticipates that cost-effective and highly efficient Bi-PSCs will emerge as a leading PV technology in both single-junction and tandem PV configurations for electricity generation in the near future.

9.
Medicina (Kaunas) ; 60(10)2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39459396

RESUMO

Background and Objectives: Stroke patients often experience changes in their pelvic tilt, trunk impairments and decreased gait and balance. While various therapeutic interventions have been attempted to improve these symptoms, there is a need for interventions that are easy to apply and reduce the physical labor of physical and occupational therapists. We aimed to investigate the immediate effects of two different methods of trunk elastic taping on the pelvic inclination, trunk impairment, balance, and gait in chronic stroke patients. Materials and Methods: We performed a single-blind randomized controlled trial involving 45 patients with chronic stroke. Participants were randomly assigned to one of three groups: forward rotation with posterior pelvic tilt taping (FRPPT, n = 14), backward rotation with posterior pelvic tilt taping (BRPPT, n = 14), or placebo taping (PT = 14). This study was conducted from December 2023 to January 2024. All the measurements were performed twice: before the intervention and immediately after the intervention. The pelvic inclination was assessed using the anterior pelvic tilt angle. The trunk impairment scale (TIS) was used to measure the trunk impairment. The balance and gait were evaluated using a force plate and walkway system. Results: The pelvic inclination was significantly different in the FRPPT and BRPPT groups compared to the PT group (p < 0.05, p < 0.001). The TIS and gait were significantly increased in the FRPPT group compared to the PT group (p < 0.05). The balance significantly improved in the FRPPT and BRPPT within groups (p < 0.05). Conclusions: Two different methods of posterior pelvic tilt taping improved the anterior pelvic tilt in chronic hemiplegic stroke patients compared with PT, and the FRPPT method also improved the trunk impairment and gait. Therefore, posterior pelvic tilt taping can be used as an intervention with immediate effect.


Assuntos
Marcha , Equilíbrio Postural , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Método Simples-Cego , Equilíbrio Postural/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Marcha/fisiologia , Idoso , Reabilitação do Acidente Vascular Cerebral/métodos , Reabilitação do Acidente Vascular Cerebral/instrumentação , Tronco/fisiopatologia , Pelve/fisiopatologia , Fita Atlética , Adulto
10.
Materials (Basel) ; 17(20)2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39459672

RESUMO

This work reports the synthesis method and various properties of four rod-like antiferroelectric (R) laterally substituted enantiomers, with or without fluorine atoms used as substituents in the benzene ring. The influence of fluorine substitution on the mesophase temperature range was determined. The synthesized compounds are three-ring rod-like smectics with a chiral center based on (R)-(-)-2-octanol. Their chemical and optical purity was checked using high-performance liquid chromatography (HPLC). Two newly synthesized enantiomers and three previously reported (R) enantiomers were used to formulate two antiferroelectric mixtures. The mesomorphic behavior was characterized by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction (XRD). The helical pitch and tilt angle measurements were done using the selective light reflection phenomenon and the electro-optical method, respectively. All the enantiomers exhibit a wide temperature range of the antiferroelectric phase, with a high tilt angle. Furthermore, the enantiomer with lateral fluorine substitution in the ortho position has a very long helical pitch (more than 2.0 µm), relatively low enthalpy of melting point, and a tilt angle close to 45 degrees. The designed (R) enantiomers can be useful for formulating eutectic mixtures for further use in various devices, including photonics and optoelectronics.

11.
Sci Rep ; 14(1): 24840, 2024 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-39438760

RESUMO

This study investigated the relationship between sagittal spinal alignment and musculoskeletal health in older women, particularly those exhibiting diminished bone density without apparent symptoms. The study assessed the impact of global tilt (GT) and the presence of coronal malalignment on spinal health. The research involved 165 asymptomatic older women with an average age of 68.91 ± 7.25 years and average body mass index of 24.26 ± 3.66 kg/m². Comprehensive standing anteroposterior and lateral spine radiographs were used for assessment. Through multivariate linear regression analysis, the study identified significant correlations between increased GT angles and various factors, including coronal malalignment, the C7 slope, and pelvic incidence. This led to the formulation of a predictive GT model: GT = -9.79 + 0.06 × menopausal period + 0.19 × body mass index (BMI)- 0.81 × average T score - 0.11 × grip strength + 3.03 × (presence of coronal malalignment) + 0.08 × sagittal vertical axis (SVA) + 0.12 × C7 slope - 0.35 × upper lumbar lordosis (ULL) - 0.43 × lower lumbar lordosis (LLL) + 0.70 × pelvic incidence (PI), with an adjusted R² of 0.816. The study findings highlight the prevalence of coronal malalignment in this demographic and its significant associations with critical spinal parameters. The proposed GT predictive model may enable development of personalized treatment plans for older women with low bone mass.


Assuntos
Densidade Óssea , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Lordose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Índice de Massa Corporal , Idoso de 80 Anos ou mais , Radiografia/métodos
12.
Sports Health ; : 19417381241283814, 2024 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-39370659

RESUMO

BACKGROUND: Maximal sprinting speed (MSS) overexposure is associated with increased risk of injury. This study aimed to describe changes in sprint performance-related factors and hamstring strain injury (HSI) risk factors after a high-volume sprinting session in soccer players. HYPOTHESIS: A high-volume sprinting session can induce acute changes in several sprint performance-related factors (sprint time and mechanical properties) and HSI risk factors (posterior chain muscle strength, hamstring range of motion, and dynamic lumbo-pelvic control [LPC], measured as changes in anterior pelvic tilt [APT] during maximal speed sprinting). STUDY DESIGN: Prospective observational case series. LEVEL OF EVIDENCE: Level 4. METHODS: Fifteen active male amateur soccer players participated. Changes in sprint performance-related factors and HSI risk factors were examined for 72 hours after high-volume MSS efforts (H-VMSSE) using a soccer-contextualized multifactorial approach. Muscle damage proxy markers (hamstring perceived soreness and creatine kinase) were also examined. RESULTS: H-VMSSE induced decrements in sprint performance-related factors. Significant reductions in theoretical maximal horizontal velocity (P < 0.01; effect size [ES], -0.71) and performance (P = 0.02; ES, -0.59) were observed for 48 and 72 hours after H-VMSSE. Small but significant reductions in posterior chain muscle force-generating capacity were detected for 48 and 72 hours after H-VMSSE for the nondominant (P < 0.03; ES, -0.60) and dominant (P < 0.04; ES, -0.40) leg. Finally, players exhibited persistent small, albeit nonsignificant (P = 0.06; ES, 0.53), decreases in dynamic LPC (APT increases) for 72 hours after H-VMSSE. CONCLUSION: H-VMSSE induced declines in both sprint performance-related factors and HSI risk factors. Sprinting can alter a player's anatomic structure by increasing APT during the maximum speed phase of the sprint. CLINICAL RELEVANCE: A soccer-contextualized multifactorial approach might allow for the regulation of MSS dosage depending on individual HSI risk factor status, thereby serving as a tailored "vaccine" for sprinting needs.

13.
Global Spine J ; : 21925682241288202, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39312910

RESUMO

STUDY DESIGN: A retrospective study. OBJECTIVES: To explore the relationship between K-line tilt and short-term surgical outcomes following laminoplasty in patients with multilevel degenerative cervical myelopathy (DCM), and to evaluate the potential of K-line tilt as a reliable preoperative predictor. METHODS: A retrospective analysis was performed for 125 consecutive patients who underwent laminoplasty for multilevel DCM. The radiographic parameters utilized in this study encompassed T1 slope (T1S), C2-C7 lordosis (CL), C2-C7 sagittal vertical axis (cSVA), T1 slope minus C2-C7 lordosis (T1S-CL), C2-C7 range of motion (ROM), and K-line tilt. The neurological recovery was evaluated using the Japanese Orthopaedic Association (JOA) score. Pearson correlation coefficients were calculated to assess the relationship between K-line tilt and other classical cervical parameters. Logistic regression analysis was employed to examine the association between K-line tilt and surgical outcomes. RESULTS: Of the 125 patients, 89 were men. The mean age of the patients was 61.74 ± 11.31 years. The results indicated a correlation between the K-line tilt and the cSVA (r = 0.628, P < 0.001), T1S (r = 0.259, P = 0.004), and T1S-CL (r = 0.307, P < 0.001). The K-line tilt showed an association with the failure of the JOA recovery rate (RR) to reach the minimal clinically important difference (MCID) and the occurrence of postoperative kyphotic deformity. We identified cutoff values for the K-line tilt which predict the failure of the JOA RR to reach the MCID and postoperative kyphotic deformity as 10.13° and 9.93°, respectively. CONCLUSIONS: The K-line tilt is an independent preoperative risk factor associated with both the failure of the JOA RR to reach the MCID and the occurrence of postoperative kyphotic deformity in patients with multilevel DCM after laminoplasty.

14.
Diagnostics (Basel) ; 14(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39272703

RESUMO

BACKGROUND: Spaceflight-Associated Neuro-Ocular Syndrome (SANS) is a complex pathology threatening the health of astronauts, with incompletely understood causes and no current specific functional diagnostic or screening test. We investigated the use of the differential performance of the visual system (central vs. perimacular visual function) as a candidate marker of SANS-related pathology in a ground-based microgravity analogue. METHODS: We used a simple reaction time (SRT) task to visual stimuli, presented in the central and perimacular field of view, as a measure of the overall performance of the visual function, during acute settings (first 10 min) of vertical, bed rest (BR), -6°, and -15° head-down tilt (HDT) presentations in healthy participants (n = 8). We built dose-response models linking the gravitational component to SRT distribution parameters in the central vs. perimacular areas. RESULTS: Acute exposure to microgravity induces detectable changes between SRT distributions in the perimacular vs. central retina (increased mean, standard deviation, and tau component of the ex-Gaussian function) in HDT compared with vertical presentation. CONCLUSIONS: Functional testing of the perimacular retina might be beneficial for the earlier detection of SANS-related ailments in addition to regular testing of the central vision. Future diagnostic tests should consider the investigation of the extra-macular areas, particularly towards the optic disc.

15.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 80(Pt 5): 362-363, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39221975

RESUMO

It is pointed out that many authors are unaware that the particular choice of unit-cell origin determines the irreducible representations to which octahedral tilts in perovskites belong. Furthermore, a recommendation is made that the preferred option is with the origin at the B-cation site rather than that of the A site.

16.
Bull Exp Biol Med ; 177(4): 401-405, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39259468

RESUMO

The paper presents an analysis of the proteomic composition in relation to both the risk of thrombosis and changes in the state of cardiomyocytes associated with the risk of cardiac fibrosis and heart failure. We examined 12 practically healthy male volunteers exposed to head-down -6° tilt bed rest (HDBR) for 21 days. The revealed decrease in the level of stimulating growth factor 2 (ST2) on days 10 and 21 relative to the initial values (background; 5 days before HDBR) indicated a decrease in the myocardial load and cardiomyocyte extensibility. The level of N-terminal prohormone of brain natriuretic peptide (NT-proBNP) increased on day 2, decreased on days 10 and 21 of HDBR relative to the background levels, and returned to baseline values after the recovery period (5 days after HDBR). The revealed changes in the level of NT-proBNP reflected the increase in circulating blood volume corresponding to HDBR duration and the role of the gravity component in increasing the functional load on the myocardium. Unchanged blood level of D-dimer at all points of the study indicates that there is no risk of thrombosis under the conditions of this study.


Assuntos
Repouso em Cama , Biomarcadores , Produtos de Degradação da Fibrina e do Fibrinogênio , Decúbito Inclinado com Rebaixamento da Cabeça , Voluntários Saudáveis , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Humanos , Peptídeo Natriurético Encefálico/sangue , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Masculino , Fragmentos de Peptídeos/sangue , Adulto , Biomarcadores/sangue
17.
J Phys Ther Sci ; 36(9): 471-475, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39239403

RESUMO

[Purpose] This study aimed to investigate the influence of seat-forward tilt angles on improving upper limb dexterity in seated tasks and to contribute to the development of seating strategies. [Participants and Methods] Seventeen healthy men (age, 20.0 ± 0.5 years; height, 175.1 ± 4.9 cm; and body weight, 63.8 ± 6.7 kg) participated in this study. The forward tilt angles of the seat were set at 0°, 15°, and 30°, with knee pads used in all conditions. The Purdue Pegboard task was used to assess upper limb dexterity, with participants inserting pins into holes in the board for 60 s. Additionally, a visual analog scale was used to evaluate the perceived ease of the task. [Results] The Purdue Pegboard task scores were 30.0 ± 2.5, 30.6 ± 2.7, and 32.5 ± 2.9 for the 0°, 15°, and 30° conditions, respectively. The visual analog scale scores were 75.3 ± 9.8, 76.4 ± 14.6, and 84.1 ± 11.1 for the 0°, 15°, and 30° conditions, respectively. Both measurements showed significantly higher values under the 30° condition than under the other two conditions. [Conclusion] These results suggest that a tilt angle of 30° provides the most significant ease and upper limb dexterity.

18.
Int J Exerc Sci ; 17(2): 810-818, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39247059

RESUMO

Heart rate variability (HRV) is used as a measure of autonomic nervous system (ANS) function and is based on heart rate (HR) beat-to-beat time interval variance analysis. Various techniques are used for recording HR, however, few studies have compared Holter-type recordings vs HR monitors (HRM) during an orthostatic challenge. OBJECTIVES: Compare HRV measures from an electrocardiogram (ECG) Holter and a HRM as a tool for investigating ANS response for post-concussion rehabilitation follow-up. METHODS: Twenty-seven participants (n = 27; 15 females, 12 males), 18 to 35 years old, non-smoking, no history of cardiac illness and physically active (3 times per week, 60 mins, moderate intensity exercise) participated in the study. ECG signals and HRM were recorded beat-to-beat (R-R) simultaneously. A motorized tilt table was set at 0 degree for supine and 85 degrees for standing position. Participants were instructed to remain for 7 minutes in each position. R-R signals from both Holter and Polar HRM recording starting points were matched before further analysis. Bland-Altman plots were used to compare recordings from the Holter (gold standard) and the Polar HRM in both positions. Unpaired t-test was used to compare measurements obtained with both systems. Significance was set at p < 0.05. RESULTS: No significant differences were observed between R-R measurements taken with both systems under equal conditions (supine and standing). Same variables under similar conditions were significantly correlated (p = 0.0001). CONCLUSION: Both recording and analysis systems (Holter vs HRM) yielded comparable results. Thus, both systems appear valid and interchangeable for HRV analysis for measuring orthostatic challenge HRV responses.

19.
Cureus ; 16(8): e66995, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39280506

RESUMO

Introduction Lumbar disc prolapse mainly occurs in the regions involving the L4-L5 and L5-S1 vertebrae. In this context, the significance of spinopelvic parameters becomes notably prominent. Non-invasive management of lumbar disc prolapse encompasses medicinal therapy, physical therapy, exercise, and epidural injections. Because of its autologous blood origin, platelet-rich plasma (PRP) therapy has minimal risks associated with immunogenic reactions and side consequences. We evaluated the extent of pain reduction and improvement of functional outcomes in patients having discogenic low back pain with modified spinopelvic parameters before and after undergoing transforaminal autologous PRP injection interventions. Methodology An observational study was conducted between September 2022 and August 2023 on 100 patients with low back pain for six months. The study population comprised patients who did not respond to conservative treatment; they were recruited from the orthopaedic ward of the emergency medicine department and outpatient department at the RL Jalappa Hospital and Research Centre affiliated with Sri Devaraj Urs Medical College in Kolar, India. Every patient received a thorough evaluation that comprised an extensive medical history, a clinical examination, and imaging of the lumbosacral spine from both the front and side views. After obtaining the patient's consent and confirming their readiness for surgery, a PRP injection was administered. The injection technique followed the standardized protocol and was performed by an experienced spine surgeon in collaboration with orthopaedic residents. Pain evaluations utilizing the Visual Analog Scale (VAS) and assessment of functional outcomes using the Oswestry Disability Index (ODI) scale were conducted before and after PRP injections at the one- and six-month follow-ups. Results The average age of the study participants was 41.82 ± 5.0 years, with 55% of them being male. A total of 39% of study samples exhibited an increased angle in spinopelvic parameters. The independent t-test revealed a statistically significant difference in the mean score of back pain, limb pain, and ODI score between patients with increased and decreased angles of spinopelvic parameters before and after injection (p=0.0001). The severity of back pain, leg pain, and functional disability was significantly reduced in patients with increased angles of spinopelvic parameters following PRP injections at the one-month follow-up (p=0.0001). However, at the six-month follow-up, patients encountered recurring symptoms and worsening back pain, leg pain, and functional disability compared to the one-month follow-up. Conversely, the severity of back pain, leg pain, and functional disability has been markedly reduced in the patients with lower spinopelvic parameter angles following PRP injections at one month (p=0.0001) and six months (p=0.0001) compared to pre-injections. Conclusion During the long-term follow-up, subjects with elevated spinopelvic parameter angles reported a lower level of improvement in functional outcome, leg pain, and back pain. The impact of spinopelvic parameters on back pain severity and functional disability is substantial, significantly affecting the functional outcome of patients with lumbar disc prolapse.

20.
Artigo em Inglês | MEDLINE | ID: mdl-39287656

RESUMO

PURPOSE: The aim of this study was to develop a methodology, based on profilometer measurements to assess the optical behaviour of Intraocular Lenses (IOls). The "Modulation Transfer Function through-object" (MTF through-object) based on vergence object displacement was calculated for different pupil sizes and pseudophakic eyes. Tilt and decentration were also analysed in a realistic cornea eye model. METHODS: For comparison between the different IOLs, an optical quality criterion based on a minimum value the MTF through-object and the recognition of simulated vision optotypes was introduced. Five IOLs were used in this study: Tecnis Eyhance, Mini Well, Tecnis Symfony, Tecnis Synergy and RayOne EMV. RESULTS: The technique was validated with previous methodologies. A general narrowing of the through-object MTF curve compared to the through-focus MTF curve was shown, resulting in greater distances between near and intermediate points and less depth of field around the far peak. The comparison between the IOLs showed that variations in corneal aberrations, pupil size and decentration caused relevant changes in IOL performance. A decrease of the SA produced a hypermetropic shift of the far focus between + 0.3 D and + 0.4 D. Most of IOLs worsen the optical quality as pupil size increased, even the MTF through-object shape changed. Decentration was an important factor in IOL implantation, causing a significant change in MTF through-object shape in most of IOLs. CONCLUSIONS: This study highlights the need to evaluate pre-operative patients for corneal aberrations and pupillary size to have the best optical success after cataract surgery in multifocal or extended depth of focus IOLs. KEY MESSAGES: What is known MTF(Modulation Transfer Function) through-focus curves (calculated in image space by moving the detector plane) can be obtained from optical bench assembly or from commercial devices. Recently, some studies proposed to characterize the lens surface design based on the profilometric measurements What is new A novel methodology based on profilometer measurements to assess the optical behaviour of Intraocular Lenses (IOls) was shown. The "Modulation Transfer Function through-object" based on vergence object displacement was introduced in order to analyse five premium IOLs. MTF through-object curve is more appropriate for studying clinical behaviour, as it provides further near and intermediate points distances and lower depth of focus around far peak compare to MTF through-focus curves. The optical behaviour of the five IOLs can vary considerably depending on the eye model and pupil size. The effect of tilt and decentration on the MTF through-object the IOLs was analysed.

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