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1.
Heliyon ; 10(9): e30338, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38720712

RESUMEN

This study developed and evaluated camel bone gelatin films (CBGFs) with glycerol or sorbitol as plasticizers. Gelatin extracted from the bones of camels (Camelus dromedarius) at ages ranging from 2.5 to 7 years was used. A comprehensive analysis was conducted, evaluating a range of properties including thickness, moisture sorption capacity, water vapor permeability (WVP), infrared spectral characteristics, light absorption behavior, solubility, as well as mechanical and thermal attributes. This thorough examination allowed for a nuanced understanding of the diverse characteristics exhibited by the camel gelatin samples across different age groups. The results indicated that camel age, glycerol, and sorbitol had a significant impact on the properties of the film (P < 0.05). Tensile strength ranged from 0.32 MPa to 3.99 MPa, while the percentage of elongation at break varied from 89.42 % to 2.68 %. Film color (lightness, L) ranged from 21.39 to 41.33. Glycerol and sorbitol plasticized films were 100 % water soluble. Moisture sorption increased with temperature (25 °C, 35 °C, and 45 °C), with sorbitol films retaining less water. WVP was low in films from old camel bones and high in glycerol-plasticized CBGF-2.5Y and CBGF-4.5Y. Thermal analysis showed a melting temperature between 158.60 °C and 174.10 °C, depending on bone age and plasticizer. These films demonstrate promise for use in food packaging, coatings, and pharmaceutical applications.

2.
Food Sci Nutr ; 10(2): 597-608, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35154695

RESUMEN

A novel intelligent pH-sensing indicator based on gelatin film and anthocyanin extracted from dragon fruit skin (Hylocereus polyrhizus) (DFSE) as a natural dye was developed to monitor food freshness by the casting method. Anthocyanin content of DFSE was 15.66 ± 1.59 mg/L. Dragon fruit bovine gelatin films were characterized by Fourier transform infrared spectroscopy (FTIR) and observed by a scanning electron microscope (SEM). Moisture content, mechanical properties, water solubility, water vapor permeability (WVP), light transmittance, color, and pH-sensing evaluations were evaluated for potential application. FTIR spectroscopy revealed that the extracted anthocyanin could interact with the other film components through hydrogen bonds. When the extract was added, films showed a smooth and clear surface as observed by SEM. The addition of anthocyanin increased the moisture content, thickness, and water solubility of the films, but decreased the WVP and light transmittance of films. Also, the incorporation of 15% v/v DFSE decreased the tensile strength from 17.04 to 12.91 MPa, increasing the elongation at break from 91.19% to 107.86%. The films showed higher ΔE with increasing DFSE content, which indicated that the film had good color variability. A significant difference in the color of the films was observed with exposure to different pH buffer solutions. The findings demonstrated that gelatin film incorporated with DFSE could be used as a visual indicator of pH variations to monitor the freshness of foods during storage time.

3.
Carbohydr Polym ; 277: 118876, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34893279

RESUMEN

Current environmental concerns fostered a strong interest in extracting polymers from renewable feedstocks. Chitosan, a second most abundant polysaccharide after cellulose, may prove to be a promising green material owing to its renewability, inherent biodegradablity, natural availability, non-toxicity, and ease of modification. This review is intended to comprehensively overview the recent developments on the isolation of chitosan from chitin, its modification and applications as a reinforcing candidate for food packaging materials, emphasizing the scientific underpinnings arising from its physicochemical properties, antimicrobial, antioxidant, and antifungal activities. We review various chitosan-reinforced composites reported in the literature and comprehensively present intriguing mechanical and other functional properties. We highlight the contribution of these mechanically robust and responsive materials to extend the shelf-life and maintain the qualities of a wide range of food commodities. Finally, we assess critical challenges and highlight future opportunities towards understanding the versatile applications of chitosan nanocomposites.

4.
Int J Biol Macromol ; 164: 4603-4612, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32941902

RESUMEN

The development of intelligent packaging based on natural and biodegradable resources is getting more attention by researchers in recent years. The aim of this study was to develop and characterize a pH-sensitive films based on sago starch and incorporated with anthocyanin from torch ginger. The pH-sensitive films were fabricated by casting method with incorporation of different torch ginger extract (TGE) concentration. The surface morphology, physicochemical, barrier, and mechanical properties as well as the pH-sensitivity of films were investigated. The film with the highest concentration of TGE showed the lowest tensile strength (4.26 N/m2), toughness (2.54 MJ/m3), Young's modulus (73.96 MPa) and water vapour permeability (2.6 × 10-4 g·m/day·kPa·m2). However, its elongation at break (85.14%), moisture content (0.27%) and water solubility (37.92%) were the highest compared to other films. pH sensitivity analysis showed that the films containing TGE extract, changes in colour by changing the pH. The colour of films changed from pink to slightly green as the pH increased from pH 4 to 9. Thus, the developed pH-sensitive film with torch ginger extract has potential as intelligent packaging for detection of food freshness or spoilage to ensure their quality and safe consumption.


Asunto(s)
Antocianinas/química , Materiales Manufacturados , Extractos Vegetales/química , Almidón/química , Zingiberaceae/química , Antocianinas/análisis , Colorimetría , Concentración de Iones de Hidrógeno , Inflorescencia/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Permeabilidad , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Agua
5.
Rural Remote Health ; 7(4): 765, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18067403

RESUMEN

BACKGROUND: The determination of cutoff points for healthy waist circumference (WC) is of paramount importance for prevention, optimum management, and prognostication of obesity, the metabolic syndrome (MetS), type 2 diabetes mellitus, and coronary heart disease. The aim of this project was to establish the cutoff level for WC in rural Basrah in Iraq, one of the eastern Mediterranean and Middle East (Arab) populations. METHODS: This was a community-based, cross-sectional survey for establishing the normal value for WC among a rural district population in Basrah (Abu-Al-khasib), Iraq. A stratified sampling procedure was used for sample selection. RESULTS: The cutoff level yielding maximum sensitivity and specificity for predicting the presence of multiple risk factors was 97 cm in men and 99 cm in women. Sensitivity and specificity using these cutoff values were 70% and 50%, respectively, in men and 70% and 45%, respectively, in women. CONCLUSION: We propose the optimal cutoff point for WC for the diagnosis of MetS in the Iraqi adult rural population as 99 cm in women and 97 cm in men.


Asunto(s)
Síndrome Metabólico/diagnóstico , Obesidad/diagnóstico , Salud Rural , Relación Cintura-Cadera , Grasa Abdominal , Adolescente , Adulto , Anciano , Antropometría , Tamaño Corporal , Estudios Transversales , Femenino , Humanos , Irak , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Curva ROC , Valores de Referencia , Factores de Riesgo
6.
J Neurol Neurosurg Psychiatry ; 68(1): 29-35, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10601397

RESUMEN

OBJECTIVES: Outcome of surgical treatment of cerebral aneurysms may be severely compromised by local cerebral ischaemia or infarction resulting from the inadvertent occlusion of an adjacent vessel by the aneurysm clip, or by incomplete aneurysm closure. It is therefore mandatory to optimise clip placement in situ to reduce the complication rate. The present study was performed to investigate the reliability of intraoperative microvascular Doppler ultrasonography (MDU) in cerebral aneurysm surgery, and to assess the impact of this method on the surgical procedure itself. METHODS: Seventy five patients (19 men, 56 women, mean age 54.8 years, range 22-84 years) with 90 saccular cerebral aneurysms were evaluated. Blood flow velocities in the aneurysmal sac and in the adjacent vessels were determined by MDU before and after aneurysm clipping. The findings of MDU were analysed and compared with those of visual inspection of the surgical site and of postoperative angiography. Analysis was also made of the cases in which the clip was repositioned due to MDU findings. RESULTS: A relevant stenosis of an adjacent vessel induced by clip positioning that had escaped detection by visual inspection was identified by Doppler ultrasonography in 17 out of 90 (18.9%) aneurysms. In addition, Doppler ultrasound demonstrated a primarily unoccluded aneurysm in 11 out of 90 (12.2%) patients. The aneurysm clip was repositioned on the basis of the MDU findings in 26 out of 90 (28.8%) cases. In middle cerebral artery (MCA) aneurysms, the MDU results were relevant to the surgical procedure in 17 out of 44 (38.6%) cases. Whereas with aneurysms of the anterior cerebral artery significant findings occurred in only five of 32 cases (15.6%; p<0.05). The clip was repositioned on the basis of the MDU results in 18 out of 50 (36%) aneurysms in patients with subarachnoid haemorrhage (SAH) grade I-V compared with only eight out of 40 (20%) aneurysms in patients without SAH (p<0.05). CONCLUSIONS: MDU should be used routinely in cerebral aneurysm surgery, especially in cases of MCA aneurysms and after SAH. Present data show that a postoperative angiography becomes superfluous whenever there is good visualisation of the "working site" and MDU findings are clear.


Asunto(s)
Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Microcirculación/diagnóstico por imagen , Microcirculación/cirugía , Persona de Mediana Edad , Ultrasonografía Doppler
7.
Acta Neurochir (Wien) ; 140(9): 925-31; discussion 930-1, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9842430

RESUMEN

Large multicenter studies have recently provided long-term results substantiating the superiority of surgical as compared to conservative treatment for symptomatic and asymptomatic extracranial internal carotid stenoses of more than 70%. These results led to an increase in the frequency of thrombo-endarteriectomies. However, indications are limited by the peri-operative complication rate. This explains the need for intra-operative quality control. The present study compares the standard method of intra-operative quality control in carotid surgery, i.e., intra-operative angiography (IOA), with direct intra-operative Doppler ultrasonography (IDU). Thirty-four patients who underwent carotid thrombo-endarteriectomy (carotid TEA) for a symptomatic (n = 15) or asymptomatic (n = 19) carotid stenosis of more than 70% were submitted to both intra-operative IOA and IDU. The sensitivity and specificity of the two techniques were compared in the light of the intra-operative findings. IDU seems to be superior to IOA in the detection of vasospasm. IOA has a higher sensitivity in demonstrating minisaccules, which, however, are not therapeutically relevant. The other findings obtained with both methods were considered to be of equal value. There were no false negative results by IDU regarding therapeutically relevant findings. We therefore consider it advisable to apply IDU in every case of carotid TEA. IOA should be performed in patients with vessel changes detected by IDU.


Asunto(s)
Estenosis Carotídea/cirugía , Endarterectomía Carotidea/instrumentación , Monitoreo Intraoperatorio/instrumentación , Ultrasonografía Doppler Transcraneal/instrumentación , Anciano , Anciano de 80 o más Años , Velocidad del Flujo Sanguíneo/fisiología , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/cirugía , Estenosis Carotídea/diagnóstico por imagen , Angiografía Cerebral , Diseño de Equipo , Femenino , Humanos , Complicaciones Intraoperatorias/diagnóstico por imagen , Complicaciones Intraoperatorias/cirugía , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/cirugía , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Ultrasonografía Doppler en Color/instrumentación
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