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1.
Med Mycol J ; 65(3): 75-82, 2024.
Artículo en Japonés | MEDLINE | ID: mdl-39218650

RESUMEN

The hyphal surface of cells of filamentous fungi is covered with cell wall, which is mainly composed of polysaccharides. Since the cell wall is the first structure to come in contact with the infection host, the environment, and the fungus itself, the elucidation of the cell wall structure and biogenesis is essential for understanding fungal ecology. Among filamentous fungi, the genus Aspergillus is an important group in the industrial, food, and medical fields. It is known that Aspergillus species form hyphal pellets in shake liquid culture. The authors previously found the role of α-1,3-glucan in hyphal aggregation in Aspergillus species. In addition, extracellular polysaccharide galactosaminogalactan contributed to hyphal aggregation as well, and dual disruption of biosynthesis genes of α-1,3-glucan and galactosaminogalactan resulted in complete hyphal dispersion in shake liquid culture. The characteristic of mycelia to form pellets under liquid culture conditions was the main reason why the growth measurement methods used for unicellular organisms could not be applied. We reported that hyphal growth of the dual disruption mutant could be measured by optical density. A real-time plate reader could be used to determine the growth curve of the mycelial growth of the dual disruption mutant. This measurement approach not only provides basic microbiological insights in filamentous fungi, but also has the potential to be applied to high-throughput screening of anti-Aspergillus drugs.


Asunto(s)
Aspergillus , Pared Celular , Hifa , Hifa/crecimiento & desarrollo , Aspergillus/genética , Glucanos/metabolismo , Microbiología Industrial/métodos
2.
Ophthalmol Ther ; 13(10): 2599-2614, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39110318

RESUMEN

INTRODUCTION: Objective markers describing corneal optical density (COD), thinnest corneal thickness (TCT), and anterior (ARC) and posterior (PRC) surface radii over the 3 mm thinnest region of the cornea were investigated to provide a model for estimating corrected distance visual acuity (CDVA) after corneal cross-linking (CXL) in keratoconus. METHODS: CDVA, COD, TCT, ARC, and PRC were monitored (using Pentacam™) over 1 year in patients with (1) keratoconus treated with routine CXL (2) relatively stable untreated keratoconus, and (3) age/gender-matched controls. RESULTS: In group 1 (n = 77), the median logMAR CDVA (mode, interquartile range) improved significantly (p < 0.01) from 0.26 (0.22, 0.12-0.65) to 0.07 (0.00, 0.02-0.21). The mean (± standard deviation, 95% confidence interval) COD (in 0-100 grey scale units) in the 0-2 mm central anterior corneal region (0-2 ant), TCT (µm), ARC (mm), and PRC (mm) changed significantly (p < 0.01), from 21.2 (± 3.70, 20.4-22.0), 454 (± 40.0, 446-462), 6.49 (± 0.71, 6.33-6.65), and 4.81 (± 0.65, 4.66-4.96) to 31.5 (± 9.19, 29.5-33.6), 423 (± 49.3, 412-434), 6.78 (± 0.80, 6.60-6.98), and 4.74 (± 0.64, 4.59-4.88), respectively, but remained stable in groups 2 (n = 23) and 3 (n = 24). Significant relationships (p < 0.01) were uncovered between postop CDVA and preop values of COD, TCT, ARC, and PRC. Multilinear regression revealed significant correlations between CDVA at 1 year and preop COD, TCT, ARC, and PRC (r2 = 0.533, r20-2ant = 0.126, r2TCT = 0.321, r2ARC = 0.506, r2PRC = 0.467). Including preop CDVA further enhanced this correlation (r2 = 0.637, r2LogMAR CDVApreop = 0.566). CONCLUSION: CXL improved CDVA, increased COD and ARC, and reduced TCT and PRC. The chance of correctly estimating the CDVA at 1 year after CXL using preoperative markers of COD, TCT, ARC, and PRC is 53%, improving to 64% with the inclusion of preoperative CDVA. Objective measurements taken at the preoperative screening stage may be useful to estimate the likely postoperative CDVA when preoperative CDVA measures are unreliable or unobtainable. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT06522789.

3.
Reprod Domest Anim ; 59(8): e14710, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39169649

RESUMEN

The reproductive efficiency in buffalo is highly influenced by seasonal variability. Angiogenesis in the reproductive cycle is important for optimal physiological functioning of uterus. Estrogen receptor-α (ERα), vascular endothelial growth factor (VEGF) and reduced nicotinamide adenine dinucleotide phosphatase diaphorase (NADPH-d) are vital indicators for the uterine angiogenic process. This study was conducted to see the effect of season on the expression of different uterine angiogenic factors. Season wise (winter and summer) and phase wise (follicular and luteal), immune staining intensity of buffalo uterus was measured by calculating the optical density value (OD) for ERα and VEGF. Percentage of immuno-positive cell count for ERα was done. Histoenzymic NADPH-d expression was analysed. Expression of all these factors increased during follicular phase of oestrous cycle in order to support the angiogenesis; however, the expression was significantly lower (p ≤ 0.05) in term of OD value as well as percentage count of immuno-positive cells during summer season indicating lower angiogenic activity that subsequently affected reproduction in buffalo.


Asunto(s)
Búfalos , Ciclo Estral , Estaciones del Año , Útero , Factor A de Crecimiento Endotelial Vascular , Animales , Búfalos/metabolismo , Femenino , Útero/metabolismo , Ciclo Estral/metabolismo , Ciclo Estral/fisiología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/genética , Neovascularización Fisiológica/fisiología
4.
Stomatologiia (Mosk) ; 103(4): 33-36, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-39171341

RESUMEN

THE AIM OF THE STUDY: Was to investigate the dynamics of mandibular density in cancer patients during therapy with zolendronic acid. MATERIALS AND METHODS: The study comprised 14 patients who received zolendronic acid at a dosage of 4 mg once every 28 days for bone metastases. In all 14 patients, measurements of mandibular density values on CT scans were performed over time. RESULTS: Using multiple linear regression analysis, a model was developed to predict the effect of the number of zolendronic acid injections «X1¼ on the dynamics of mandibular density «Y¼. The resulting formula for predicting mandibular density is Y = 5.9 X1 + 49 HU. CONCLUSION: The model has limitations due to the study design but still can be used by oncologists and dentists to assess mandibular density in patients taking zolendronic acid.


Asunto(s)
Conservadores de la Densidad Ósea , Difosfonatos , Imidazoles , Mandíbula , Ácido Zoledrónico , Humanos , Femenino , Mandíbula/efectos de los fármacos , Mandíbula/diagnóstico por imagen , Ácido Zoledrónico/administración & dosificación , Ácido Zoledrónico/farmacología , Masculino , Imidazoles/administración & dosificación , Imidazoles/farmacología , Persona de Mediana Edad , Difosfonatos/administración & dosificación , Difosfonatos/farmacología , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/secundario , Densidad Ósea/efectos de los fármacos , Anciano , Tomografía Computarizada por Rayos X , Adulto
5.
Curr Eye Res ; : 1-9, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105271

RESUMEN

PURPOSE: The objective of this study was to observe the macular pigment optical density (MPOD) and the relationship between MPOD and retinal thickness in Chinese primary angle-closure glaucoma (PACG) patients by the one-wavelength reflectometry method. METHODS: This study was a prospective comparative observational study, including 39 eyes from 39 PACG patients (15 men and 24 women, mean age 61.89 ± 12.30) and 41 eyes from 41 controls (20 men and 21 women, mean age 63.24 ± 14.02). We measured the MPOD 7-degree area by the one-wavelength reflectometry method and analyzed both the max and mean optical density (OD). The central retinal thickness (CRT) and the total thickness of the macular ganglion cell layer (GCL), and inner plexiform layer (IPL)were measured by spectral-domain-optical coherence tomography (SD-OCT). Statistical methods such as Shapiro-Wilk test, Fisher's exact test, chi-square test, two independent samples test and Spearman's correlation coefficient were used to observe the differences in the MPOD between normal subjects and PACG patients and the correlation between the MPOD and retinal thickness. RESULTS: The max optical density (Max OD) (PACG group: 0.302 ± 0.067d.u, control group: 0.372 ± 0.059d.u., p < .001) and mean optical density (Mean OD) (PACG group: 0.124 ± 0.035d.u., control group: 0.141 ± 0.028d.u., p < 0.05) were significantly reduced in PACG patients compared with control subjects. Significant decreases in GCL + IPL thickness (PACG group: 74.71 ± 39.56 µm, control group:113.61 ± 8.14 µm, p < 0.001) and CRT (PACG group: 254.49 ± 41.47 µm, control group:329.10 ± 18.57 µm, p < 0.001) were also observed in PACG eyes. There was no statistically significant correlation between the MPOD and GCL + IPL thickness (p = .639, p = .828). CONCLUSIONS: MPOD was significantly lower in Chinese PACG patients than in the control group, potentially due to thinning of the GCL + IPL thickness. This study provides insights for the pathophysiology, assessment of PACG and potential guidance for lifestyle modifications.


In this study, we measured the MPOD values of Chinese PACG patients for the first time using the one-wavelength reflectance method and clarified that the MPOD of PACG patients was significantly lower than that of the normal group. This study provides insights for the pathophysiology, assessment of PACG and potential guidance for lifestyle modifications.

6.
Med Phys ; 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39186784

RESUMEN

BACKGROUND: Radiochromic film (RCF) dosimeters with their high spatial resolution and tissue equivalent properties are conveniently used for two-dimensional and small-field dosimetry. OC-1 is a new model of RCF dosimeter that was commercially introduced recently. Due to its novelty there is a need to characterize its response in various radiation beam types. PURPOSE: To study the response of OC-1 RCFs to megavoltage clinical x-ray, electron, and proton beams, as well as kilovoltage x-ray beams used in a small animal research irradiator. MATERIALS AND METHODS: OC-1 RCFs were cut into ∼4 × 4 cm2 pieces. RCF samples were irradiated at various dose levels in the range 0.5-120 Gy using different modalities; a small animal radiation research platform (SARRP) (220 kVp), a medical linear accelerator (6 MV, 10 MV, 15 MV, 6 MV FFF, 10 MV FFF photon beams, as well as 6 and 20 MeV electron beams), and a gantry-mounted proton therapy synchrocyclotron. In order to study any dependency on the fractionation scheme, same dose was delivered at several fractions to a set of films. Different dose rates in the range 200-600 MU/min were delivered to a set of films to investigate any dose rate dependency. The films were scanned pre-irradiation and at 48 h post-irradiation using a flatbed scanner. The net optical density (OD) was measured for red, green, and blue color channel for each film. The orientation dependency was studied by scanning the films at eight different orientations. In order to study the temporal evolution of the response of the films, film samples were irradiated at 10 and 50 Gy using 6 MV photon beams and were scanned upon irradiation at certain time intervals up to 3 months. The spectral response of the films were studied over the visible range using a spectrometer. RESULTS: For megavoltage photon, electron, and plateau region of the proton beams, we did not observe a significant dependency on the beam quality, dose rate, and fractionation scheme. At the kV beam, an unusual over-response was observed in the films' net OD. An orientation dependency in the response of the films with a sinusoidal trend was observed. The response of the films increased with time following a double or triple exponential trend. The spectral absorption peaks were blue-shifted with dose. CONCLUSION: OC-1 RCFs were found to be reliable dosimeters with no significant energy dependency in MV range for photon and electron beams including the FFF beams. They over-respond when irradiated by kV x-ray beams compared to MV x-ray beams. Caution must be exercised to maintain the orientation of the films when scanning. Due to the temporal growth in the net OD of the films, same post-irradiation time interval must be used for scanning the calibration and test films.

7.
Eur J Ophthalmol ; : 11206721241272254, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39161229

RESUMEN

Purpose: The objective of the present study was to investigate the relationship between macular pigment optical density (MPOD) and plasma carotenoids [(L) and (Z)] and serum lipids in South Indian young healthy volunteers and patients with early age-related macular degeneration (AMD). Methods: Two hundred and fourteen (N = 214) study participants (Healthy control group (N) = 178; Early AMD group (N) = 36) were enrolled after getting their written informed consent. The MPOD of the study participants was assessed using MPS II (Electron Technology, UK) after completing their routine ocular examination. Serum lipids were measured by the standard technique. Plasma levels of L, Z, lycopene and beta-carotene were estimated by high performance liquid chromatography with photo diode array detector. Statistical analysis used: Correlations among variables in serum, plasma and the MPOD were established using Spearman's rho correlation coefficient. Results: The overall mean MPOD in healthy control group and early AMD group were found to be 0.47 ± 0.16 (N = 178; 317 eyes) and 0.35 ± 0.22 (N = 36; 38 eyes) at 1° eccentricity respectively and were found to be statistically significant (p < 0.001). A strong positive association was found between plasma L, Z and L + Z and MPOD. Serum HDL showed a strong negative association with MPOD and other lipids showed a very weak association. MPOD was unaffected by body mass index. Conclusions: MPOD is positively associated with plasma L,Z and L + Z, adding further evidence that additional intake of L/Z may be beneficial in delaying the risk of AMD in our population.

8.
Diagnostics (Basel) ; 14(14)2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39061693

RESUMEN

The study aimed to investigate the extended effects and interrelations of corneal biomechanics, corneal optical density (COD), corneal thickness (CT), and intraocular pressure (IOP) following cataract surgery. Sixteen eyes were analyzed prospectively. The Corneal Visualization Scheimpflug Technology (Corvis ST) device assessed corneal biomechanics, while the Pentacam AxL® (Pentacam) measured COD and CT. Postoperative data were collected around six months after surgery, with a subgroup analysis of data at nine months. The Pearson correlation was used to examine the relationship between surgical-induced changes in corneal biomechanics and COD. At six months, significant postoperative differences were observed in various biomechanical indices, including uncorrected IOP (IOPuct) and biomechanics-corrected IOP (bIOP). However, many indices lost statistical significance by the nine-month mark, suggesting the reversibility of postoperative corneal changes. Postoperative COD increased at the anterior layer of the 2-6 mm annulus and incision site. The changes in COD correlated with certain biomechanical indices, including maximal (Max) deformative amplitude (DA) and stiffness parameter (SP). In conclusion, despite significant immediate postoperative changes, corneal biomechanics, COD, and IOP experienced a gradual recovery process following cataract surgery. Clinicians should maintain vigilance for any unusual changes during the short-term observation period to detect abnormalities early.

9.
J Comp Neurol ; 532(7): e25649, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967410

RESUMEN

The physiological aging process is well known for functional decline in visual abilities. Among the components of the visual system, the dorsal lateral geniculate nucleus (DLG) and superior colliculus (SC) provide a good model for aging investigations, as these structures constitute the main visual pathways for retinal inputs reaching the visual cortex. However, there are limited data available on quantitative morphological and neurochemical aspects in DLG and SC across lifespan. Here, we used optical density to determine immunoexpression of glial fibrillary acidic protein (GFAP) and design-based stereological probes to estimate the neuronal number, total volume, and layer volume of the DLG and SC in marmosets (Callithrix jacchus), ranging from 36 to 143 months of age. Our results revealed an age-related increase in total volume and layer volume of the DLG, with an overall stability in SC volume. Furthermore, a stable neuronal number was demonstrated in DLG and superficial layers of SC (SCv). A decrease in GFAP immunoexpression was observed in both visual centers. The results indicate region-specific variability in volumetric parameter, possibly attributed to structural plastic events in response to inflammation and compensatory mechanisms at the cellular and subcellular level. Additionally, the DLG and SCv seem to be less vulnerable to aging effects in terms of neuronal number. The neuropeptidergic data suggest that reduced GFAP expression may reflect morphological atrophy in the astroglial cells. This study contributes to updating the current understanding of aging effects in the visual system and stablishes a crucial foundation for future research on visual perception throughout the aging process.


Asunto(s)
Envejecimiento , Callithrix , Cuerpos Geniculados , Proteína Ácida Fibrilar de la Glía , Neuronas , Animales , Envejecimiento/fisiología , Envejecimiento/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Proteína Ácida Fibrilar de la Glía/biosíntesis , Neuronas/metabolismo , Masculino , Cuerpos Geniculados/metabolismo , Femenino , Colículos Superiores/metabolismo , Vías Visuales/metabolismo
10.
Front Neurol ; 15: 1414898, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39036639

RESUMEN

Background: The density of contrast medium in digital subtraction angiography (DSA) have been used to evaluate the cerebral circulation function. Our aim was to study the effect of difference in arteriovenous peak optical density (POD) after thrombectomy on functional outcomes. Methods: Consecutive patients with acute ischemic stroke due to large vessel occlusion who underwent thrombectomy were reviewed. We processed DSA images with ImageJ software to measure the POD of internal carotid artery (ICA) and cortical veins. The average POD of cortical veins (PODVA) and the POD difference between ICA and cortical veins (PODICA-CV) were calculated. Primary outcome was good functional outcome (modified Rankin scale score of 0-2 at 90 days). Results: One hundred sixty-six patients were finally included in the study. Patients with good functional outcome had lower ipsilateral PODVA (median [interquartile range (IQR)], 257.198 [216.623-296.631] vs. 290.944 [248.647-338.819], p < 0.001) and lower ipsilateral PODICA-CV (median [IQR], 128.463 [110.233-153.624] vs. 182.01 [146.621-211.331], p < 0.001). Multivariable logistic regression analyses showed that ipsilateral PODVA (odds ratio [OR] 0.991, 95% confidence interval [CI] 0.984-0.999, p = 0.019) and ipsilateral PODICA-CV (OR 0.975, 95% CI 0.963-0.986, p < 0.001) were associated with good functional outcome. The predictive ability was significantly enhanced in the model including ipsilateral PODICA-CV (0.893 vs. 0.842, p = 0.027). No correlation was found between ipsilateral PODICA-CV and expanded Thrombolysis in Cerebral Infarction grades (r = -0.133, p = 0.099). Conclusion: Ipsilateral PODICA-CV is an additional indicator of cerebral reperfusion status and predicts functional outcomes after thrombectomy.

11.
Conserv Physiol ; 12(1): coae035, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38840751

RESUMEN

Animals face several challenges in their natural environment, and to cope with such conditions, they may exhibit contrasting physiological responses that directly affect their overall well-being and survival. In this study, we assessed physiological responses via faecal glucocorticoid metabolite (fGCM) measurements in free-ranging mugger crocodiles inhabiting diverse habitats in Gujarat, India. We sampled muggers within Charotar, a rural area (Zone A) with local people having high tolerance towards the presence of muggers, and Vadodara, a region having both urban (Zone B) and rural (Zone C) areas with high levels of human-mugger conflict (HMC). Further, muggers in Vadodara live in water bodies that are mostly polluted due to sewage disposal from adjoining chemical industries. To measure fGCM (mean ± SEM, ng/g dry faeces) levels in muggers, scats were collected during both breeding (N = 107 scats) and non-breeding (N = 22 scats) seasons from all three zones. We used captive muggers (a focal enclosure) to biologically validate (via capture and restraint) the selected fGCM assay (11-oxoetiocholanolone assay). We showed a significant (P < 0.05) 11-fold increase in fGCM levels between pre-capture (540.9 ± 149.2, N = 11) and post-capture (6259.7 ± 1150.5, N = 11) samples. The validated assay was applied to free-ranging muggers during the breeding season, and Zone A showed significantly (P < 0.05) lower fGCM levels (542.03 ± 71.3) compared to muggers of Zone B (1699.9 ± 180.8) and Zone C (1806.4 ± 243.2), both zones having high levels of HMC with polluted water bodies. A similar contrast in fGCM levels was also observed during the non-breeding season. Overall, the study demonstrated that fGCM levels in muggers varied across habitats, and such variation could be due to a multitude of ecological factors that the species experience in their immediate local environment. Moreover, high fGCM levels in muggers of Vadodara during both breeding and non-breeding seasons may indicate a condition of chronic stress, which could be maladaptive for the species.

12.
Stomatologiia (Mosk) ; 103(3): 21-25, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38904555

RESUMEN

THE AIM THE STUDY: To analyze the density of the mandible in cancer patients during treatment with zoledronic acid. MATERIALS AND METHODS: A retrospective cohort study included 45 patients with cancer aged 26-81 years (average age 55±12.88 years), of whom 14 patients had bone metastases (n=14) and took 4 mg of zolendronic acid once every 28 days. The patients underwent standard PET-CT examinations in the «whole body¼ mode, and the density of the mandible was examined on CT. Radiation therapy was performed by intracavitary administration of strontium 89 chloride; remote radiation therapy with cisplatin radiomodification. In the presence of bone metastases, patients received complex supportive therapy with zolendronic acid. The effect of zolendronic acid on the density of the mandible in the frontal and lateral sections was studied by multidimensional dispersion analysis. RESULTS: Statistically significant differences (p=0.002) were revealed for density indicators according to CT scans of the mandible in the frontal region against the background of zolendronic acid therapy. We attribute the absence of statistically significant differences for the density of the mandible in the lateral sections (p=0.101 and p=0.082) against the background of zolendronic acid therapy to a measurement bias. We attribute the absence of statistically significant differences in density indices against the background of hormonal, radiation, targeted and chemotherapy to the design of the study. CONCLUSION: Density measurement based on CT examination data can be recommended for use as an additional tool in assessing the effect of zolendronic acid on the density of the mandible. However, the method of measuring the density of the mandible in the lateral sections requires improvement to prevent measurement bias.


Asunto(s)
Conservadores de la Densidad Ósea , Densidad Ósea , Mandíbula , Ácido Zoledrónico , Humanos , Persona de Mediana Edad , Anciano , Ácido Zoledrónico/uso terapéutico , Ácido Zoledrónico/administración & dosificación , Ácido Zoledrónico/farmacología , Estudios Retrospectivos , Mandíbula/diagnóstico por imagen , Mandíbula/efectos de los fármacos , Masculino , Adulto , Femenino , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Densidad Ósea/efectos de los fármacos , Neoplasias Óseas/secundario , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/radioterapia , Neoplasias Óseas/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Difosfonatos/farmacología
13.
Microorganisms ; 12(6)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38930433

RESUMEN

Chlorella vulgaris is of great importance in numerous exploratory or industrial applications (e.g., medicals, food, and feed additives). Rapid quantification of algal biomass is crucial in photobioreactors for the optimization of nutrient management and the estimation of production. The main goal of this study is to provide a simple, rapid, and not-resource-intensive estimation method for determining the algal density of C. vulgaris according to the measured parameters using UV-Vis spectrophotometry. Comparative assessment measurements were conducted with seven different methods (e.g., filtration, evaporation, chlorophyll a extraction, and detection of optical density and fluorescence) to determine algal biomass. By analyzing the entire spectra of diluted algae samples, optimal wavelengths were determined through a stepwise series of linear regression analyses by a novel correlation scanning method, facilitating accurate parameter estimation. Nonlinear formulas for spectrometry-based estimation processes were derived for each parameter. As a result, a general formula for biomass concentration estimation was developed, with recommendations for suitable measuring devices based on algae concentration levels. New values for magnesium content and the average single-cell weight of C. vulgaris were established, in addition to the development of a rapid, semiautomated cell counting method, improving efficiency and accuracy in algae quantification for cultivation and biotechnology applications.

14.
Semin Ophthalmol ; : 1-9, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717910

RESUMEN

PURPOSE: This systematic review studies the relationship between Macular Pigment Optical Density (MPOD) values and cognitive and visual function in childhood. METHODS: It included cross-sectional, observational studies or controlled clinical trials in humans between 0 and 18 years of age, analyzing MPOD values in 3 main databases: PubMed, Scopus and Web of Science. The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement recommendations. RESULTS: Thirteen studies were included in this systematic review. The relationship of cognitive function, visual function and diverse variables with MPOD was analyzed in 4, 4 and 5 studies, respectively. The age of the participants ranged between premature infants to 12 years. Most of the studies used Heterochromatic Flicker Photometry (HFP) with macular densitometer to obtain MPOD values. MPOD values ranged between 0 (undetectable) to 0.66 ± 0.03 d.u. Only 4 articles studied the relationship between MPOD values and dietary intake of lutein and zeaxanthin using questionnaires about diet. CONCLUSIONS: Lutein and zeaxanthin accumulation plays an important role during the maturational stage and childhood development. Although cognitive function is more strongly correlated with MPOD values, the relationship with visual function remains unclear, and further studies are required to support this relationship.

15.
Ophthalmic Physiol Opt ; 44(5): 917-924, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38572814

RESUMEN

PURPOSE: The Beer-Lambert law suggests that visual pigment optical density (OD) should be linearly related to the length of photoreceptor outer segments (POSs). Mammalian studies indicate that visual pigment concentration increases with POS length, but the nature of this relationship may vary due to factors such as visual pigment packing density or retinal eccentricity, and may not necessarily be linearly related. The purpose of this study was to establish the relationship between OD and POS length in humans. METHODS: Spectral domain optical coherence tomography (OCT) was used to image POS, and imaging retinal densitometry (IRD) was used to measure OD at corresponding locations in 19 healthy participants (age range 25-82 years). POS length and OD measurements were extracted from OCT and IRD images at 23 discrete locations spanning the central 9° of the retina. The averaged data from all participants were fitted with models based on the Beer-Lambert law to establish the relationship between OD and POS length. RESULTS: Visual pigment OD increased monotonically with POS length, but the relationship was non-linear, and a straight-line fit, based on a simple interpretation of the Beer-Lambert law, provided a poor description. A model allowing for different rod and cone visual pigment concentrations provided a superior fit. Specifically, the data were well described by a model where the molar concentration of visual pigment in cones and rods were 3.8 × 10-3 mol/L and 1.8 × 10-3mol/L, respectively. CONCLUSIONS: In accordance with the Beer-Lambert law, the results indicate that OD increases monotonically with POS length in humans, but the precise relationship is dependent on photoreceptor type. These results suggest that visual pigment concentration in rods is only about 48% of that found in cones. This may be due to the ubiquitous nature of artificial light that works to reduce the concentration of rhodopsin in rod photoreceptors.


Asunto(s)
Segmento Externo de las Células Fotorreceptoras Retinianas , Pigmentos Retinianos , Tomografía de Coherencia Óptica , Humanos , Anciano , Tomografía de Coherencia Óptica/métodos , Persona de Mediana Edad , Adulto , Masculino , Femenino , Anciano de 80 o más Años , Segmento Externo de las Células Fotorreceptoras Retinianas/metabolismo , Pigmentos Retinianos/análisis , Pigmentos Retinianos/metabolismo , Retina/diagnóstico por imagen , Retina/metabolismo
16.
Adv Nutr ; 15(5): 100216, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38582248

RESUMEN

Antioxidants are bioactive molecules that function to scavenge free radicals and balance oxidative stress. Although all antioxidants can act as reactive oxygen species scavengers, their efficacy on eye health may vary. Moreover, the comparative effectiveness and potential additive effect between groups of antioxidants, hitherto, have not been systematically studied. A systematic review and network meta-analysis were conducted to investigate the comparative or additive effect of dietary antioxidant supplements on eye health. Four databases (PubMed, Embase, CINAHL, and Cochrane) were searched, and relevant randomized controlled trials were identified. Out of 60 articles selected for systematic review, 38 were included in the network meta-analysis, categorized into 8 distinct antioxidant-supplemented groups and placebo. All groups significantly increased macular pigment optical density and contrast sensitivity at low spatial frequency, whereas only the antioxidant mixture + lutein (L) + fatty acid combination exhibited significant improvements in visual acuity (hazard ratio = -0.15; 95% confidence interval: -0.28, -0.02) and L + zeaxanthin combination for photostress recovery time (hazard ratio = -5.75; 95% confidence interval: -8.80, -1.70). Especially, the L + zeaxanthin + fatty acid combination was ranked best for macular pigment optical density (surface under the cumulative ranking: 99.3%) and second best for contrast sensitivity at low spatial frequency (67.7%). However, these findings should be interpreted with caution due to low quality of evidence, primarily influenced by indirectness and potential publication bias. Overall, antioxidant supplementation was estimated to improve eye health parameters, whereas different combinations of antioxidants may also have varying effects on improving visual health from multiple perspectives. This study was registered at PROSPERO as CRD42022369250.


Asunto(s)
Antioxidantes , Suplementos Dietéticos , Luteína , Pigmento Macular , Ensayos Clínicos Controlados Aleatorios como Asunto , Agudeza Visual , Humanos , Antioxidantes/administración & dosificación , Antioxidantes/farmacología , Luteína/farmacología , Luteína/administración & dosificación , Agudeza Visual/efectos de los fármacos , Zeaxantinas/farmacología , Zeaxantinas/administración & dosificación , Metaanálisis en Red , Sensibilidad de Contraste/efectos de los fármacos
17.
J Fluoresc ; 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38334915

RESUMEN

In this article, Fluorescence spectroscopy has been employed for the identification of Pseudomonas aeruginosa (PA) and Escherichia coli (E. coli) in water suspension. Emission spectra of PA and E. coli suspensions have been acquired by using excitation wavelengths from 270 to 420 nm with steps of 10 nm to explore their spectral features. It has been found that the emission spectra of tryptophan, tyrosine, NADH and FAD, being the intracellular biomolecules present in both bacteria, can be used as fingerprints for their identification, differentiation and quantification. Both bacterial strains can clearly be differentiated from water and from each other by using λex 270-290 nm through spectral analysis and from λex: 300-500 nm by applying statistical analysis. Furthermore, calibration curves for different bacterial loads of PA and E. coli suspensions have been produced between colonies forming units per ml (CFUs/ml) the integrated intensities of their emission spectra. CFUs/ml of both bacterial suspensions have been determined through plate count method which was used as cross-reference for the analysis of emission spectra of both bacterial suspensions. These curves may be used to estimate CFU/ml of both PA and E. coli in unknown water suspensions by determining the integrating intensity of their emission spectra.

18.
Appl Microbiol Biotechnol ; 108(1): 76, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38194144

RESUMEN

Bacillus anthracis is an etiological agent of anthrax, a severe zoonotic disease that can be transmitted to people and cause high mortalities. Bacteriophages and their lytic enzymes, endolysins, have potential therapeutic value in treating infections caused by this bacterium as alternatives or complements to antibiotic therapy. They can also be used to identify and detect B. anthracis. Endolysins of two B. anthracis Wbetavirus phages, J5a and F16Ba which were described by us recently, differ significantly from the best-known B. anthracis phage endolysin PlyG from Wbetavirus genus bacteriophage Gamma and a few other Wbetavirus genus phages. They are larger than PlyG (351 vs. 233 amino acid residues), contain a signal peptide at their N-termini, and, by prediction, have a different fold of cell binding domain suggesting different structural basis of cell epitope recognition. We purified in a soluble form the modified versions of these endolysins, designated by us LysJ and LysF, respectively, and depleted of signal peptides. Both modified endolysins could lyse the B. anthracis cell wall in zymogram assays. Their activity against the living cells of B. anthracis and other species of Bacillus genus was tested by spotting on the layers of bacteria in soft agar and by assessing the reduction of optical density of bacterial suspensions. Both methods proved the effectiveness of LysJ and LysF in killing the anthrax bacilli, although the results obtained by each method differed. Additionally, the lytic efficiency of both proteins was different, which apparently correlates with differences in their amino acid sequence. KEY POINTS: • LysJ and LysF are B. anthracis-targeting lysins differing from lysins studied so far • LysJ and LysF could be overproduced in E. coli in soluble and active forms • LysJ and LysF are active in killing cells of B. anthracis virulent strains.


Asunto(s)
Carbunco , Bacillus anthracis , Bacillus , Bacteriófagos , Humanos , Escherichia coli
19.
Heliyon ; 10(1): e23361, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38163108

RESUMEN

Background: Macular pigment in retina is formed by lutein and zeaxanthin. These carotenoids must be ingested. Fruit, vegetables, and eggs are rich in lutein and zeaxanthin. In adults, there are many factors that increase macular pigment values, although not enough studies have been performed in children. Objective: The main aim of this study was to analyze macular pigment in children considering healthy habits and exposure to LEDs screens. Methods: A cross-sectional, observational study was conducted, recruiting 27 children aged 7-13 years. Healthy habits, demographic data and exposure to LEDs were analyzed using a questionnaire. To study adherence to the Mediterranean diet, the validated KIDMED questionnaire was used. Macular pigment optical density was measured using Heterochromatic Flicker Photometry, and weight and height were also recorded and expressed by body mass index. Results: The mean MPOD value was 0.45 ± 0.14. BMI percentile was studied in the children, with most of them presenting normal weight (55.55 %). Regarding the KIDMED questionnaire, ingesting a fruit or fruit juice every day increases macular pigment optical density (0.47 ± 0.13 vs 0.24 ± 0.07, p = 0.034). No correlation was found for the KIDMED questionnaire score, BMI or age with MPOD value. Conclusion: Lutein and zeaxanthin intake, as well as healthy habits, increase MPOD value. However, no relation was found for several of the factors evaluated with MPOD value.

20.
Jpn J Ophthalmol ; 68(1): 19-25, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37966565

RESUMEN

PURPOSE: To develop a method to measure the macular pigment optical density (MPOD) using scanning laser ophthalmoscopic images in young adults and children. STUDY DESIGN: Cross-sectional study. METHODS: Blue light reflectance fundus images of 32 healthy subjects were used. A profile of the linear reflectance changes across the center of the fovea on a grayscale fundus image was generated. The ratio of the macula-to-periphery reflection was designated as the peak value of the MPOD (MPOD[FR]) based on established fundamentals. In the MPOD profile, the basal width of the pixels at MPOD < 0 (wMP) and width at one-half value of the MPOD[FR] (wMP0.5) were determined. The MOPD at eccentricity of 0.5° was measured by heterochromatic flicker photometry (MPOD[HFP]), and the correlation between the MPOD[FR] and MPOD[HFP] was evaluated. RESULTS: The MPOD[FR] ranged from 0.17 to 0.73 with a mean of 0.40 ± 0.13. The wMP ranged from 88 to 173 pixels with a mean of 121.7 ± 24.2 pixels, and the wMP0.5 ranged from 38 to 83 pixels with a mean of 54.1 ± 10.3 pixels. A significant correlation was found between the MPOD[FR] and MPOD[HFP] (r = 0.41, P = 0.02). CONCLUSIONS: This simplified method can provide accurate and reliable values of the MPOD comparable to heterochromatic flicker photometry. Obtaining the fundus images in this fast and easy way should be suitable for children thus enabling clinicians to determine the MPODs for children.


Asunto(s)
Mácula Lútea , Pigmento Macular , Adulto Joven , Niño , Humanos , Estudios Transversales , Fotometría , Rayos Láser
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