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1.
PLoS One ; 18(3): e0281860, 2023.
Article de Anglais | MEDLINE | ID: mdl-36913325

RÉSUMÉ

Drug delivery via aerosolization for localized and systemic effect is a non-invasive approach to achieving pulmonary targeting. The aim of this study was to prepare spray-dried proliposome (SDP) powder formulations to produce carrier particles for superior aerosolization performance, assessed via a next generation impactor (NGI) in combination with a dry powder inhaler. SDP powder formulations (F1-F10) were prepared using a spray dryer, employing five different types of lactose carriers (Lactose monohydrate (LMH), lactose microfine (LMF), lactose 003, lactose 220 and lactose 300) and two different dispersion media. The first dispersion medium was comprised of water and ethanol (50:50% v/v ratio), and the second dispersion medium comprised wholly of ethanol (100%). In the first dispersion medium, the lipid phase (consisting of Soya phosphatidylcholine (SPC as phospholipid) and Beclomethasone dipropionate (BDP; model drug) were dissolved in ethanol and the lactose carrier in water, followed by spray drying. Whereas in second dispersion medium, the lipid phase and lactose carrier were dispersed in ethanol only, post spray drying. SDP powder formulations (F1-F5) possessed significantly smaller particles (2.89 ± 1.24-4.48 ± 1.20 µm), when compared to SDP F6-F10 formulations (10.63 ± 3.71-19.27 ± 4.98 µm), irrespective of lactose carrier type via SEM (scanning electron microscopy). Crystallinity of the F6-F10 and amorphicity of F1-F15 formulations were confirmed by XRD (X-ray diffraction). Differences in size and crystallinity were further reflected in production yield, where significantly higher production yield was obtained for F1-F5 (74.87 ± 4.28-87.32 ± 2.42%) then F6-F10 formulations (40.08 ± 5.714-54.98 ± 5.82%), irrespective of carrier type. Negligible differences were noted in terms of entrapment efficiency, when comparing F1-F5 SDP formulations (94.67 ± 8.41-96.35 ± 7.93) to F6-F10 formulations (78.16 ± 9.35-82.95 ± 9.62). Moreover, formulations F1-F5 demonstrated significantly higher fine particle fraction (FPF), fine particle dose (FPD) and respirable fraction (RF) (on average of 30.35%, 890.12 µg and 85.90%) when compared to counterpart SDP powder formulations (F6-F10). This study has demonstrated that when a combination of water and ethanol was employed as dispersion medium (formulations F1-F5), superior formulation properties for pulmonary drug delivery were observed, irrespective of carrier type employed.


Sujet(s)
Béclométasone , Lactose , Poudres , Taille de particule , Administration par inhalation , Inhalateurs à poudre sèche , Éthanol , Eau , Lipides , Aérosols , Vecteurs de médicaments
2.
Microsc Res Tech ; 85(4): 1410-1420, 2022 Apr.
Article de Anglais | MEDLINE | ID: mdl-34850481

RÉSUMÉ

Pollen micromorphology is not only used to check the functional and structural evolution in plants but also to solve the taxonomic problem related to the classification of plants. Therefore, keeping in view the significance of pollen traits, selected taxa of the subfamily Caesalpiniaceae was collected from different geographical regions of Pakistan. The species were then analyzed under both light microscopy and scanning electron microscopy techniques to investigate the importance of micromorphological characters of pollen in the identification and classification of species. Great variation was recorded in equatorial shape, surface ornamentation, tectum, polar diameter, equatorial diameter, and exine thickness. However, little variation was observed in pollen type, polar shape, and fertility of pollen. The equatorial shape of five types was observed: prolate, prolate-spheroidal, spheroidal-subprolate, subspheroidal-prolate, and subspheroidal. Four types of surface ornamentation, psilate, granulate, clavate, and perforate, were recorded. Tectum of five types, intactate, reticulate regulate, medium reticulate, tactate, and striate, was observed. Sexine was thicker than nexine in all studied species. The largest polar diameter was observed in Caesalpinia pulcherrima 64.1 µm while the smallest in Parkinsonia aculeata 26.1 µm. The largest equatorial diameter was found in C. pulcherrima of 70.25 µm whereas the smallest in P. aculeata 27.57 µm. All the pollens analyzed were tricolporate. All studied species have a fertility ratio of more than 90%. A taxonomic key was developed to show the variation in pollen features and delimit species for the correct identification. In conclusion, the pollen traits were found useful to define species boundaries at various taxonomic ranks and will strengthen the taxonomy of this subfamily. Besides, this study also explored the palynological traits and their implication in the taxonomy of the subfamily Caesalpiniaceae.


Sujet(s)
Caesalpinia , Pollen , Microscopie électronique à balayage , Pakistan , Pollen/anatomie et histologie
3.
Microsc Res Tech ; 82(7): 1073-1082, 2019 Jul.
Article de Anglais | MEDLINE | ID: mdl-30901145

RÉSUMÉ

Seed micromorphological and macromorphological characteristics of 12 taxa of Caesalpiniaceae from Pakistan have been studied, using light and scanning electron microscopy, to investigate the importance of seed coat features as a taxonomic tool. Great variations have been observed in color, shape, dimension, and seed surface pattern among the different genera of the family. A taxonomic key was prepared for the studied taxa. Six types of seed shapes were observed; circular, elliptical, irregular, oblong, oval, and ovoid. All examined seeds were hard except fragile seeds of Haematoxylom campechianum. Eight types of surface ornamentation have been noticed that include levigate, lugose, papillate, reticulate, reticulate irregular, reticulate regular, rhombus, and rogues. Majority of the taxa has been observed with thick ornamentation wall but thin ornamentation wall has also been recorded in few species. Fracture line of the various patterns was present in all taxa except genus Bauhinia. Three types of texture crudeness; coarse, medium, and fine have been recorded. Both micromorphological and macromorphological characters of seed are very fruitful in identification and classification of Caesalpiniaceae.


Sujet(s)
Caesalpinia/anatomie et histologie , Graines/anatomie et histologie , Graines/ultrastructure , Caesalpinia/classification , Microscopie , Microscopie électronique à balayage , Pakistan
4.
J Med Imaging Radiat Sci ; 50(1): 24-30, 2019 Mar.
Article de Anglais | MEDLINE | ID: mdl-30777244

RÉSUMÉ

BACKGROUND: The automatic detection of common subregions and registration in multimodal functional and structural images is challenging. This article gives an overview of multimodal image registration and the developments and technical issues with automatic detection and registration of subregions of interest in multimodal images. DISCUSSION: The available knowledge about subregion detection and registration in multimodal images are described in detail. Besides the provision of compact knowledge on subregion detection and registration, the challenges and proposed solutions are also discussed. CONCLUSION: This article provides research guidelines for the development of automatic detection and registration of subregions of interest in functional and structural images with high accuracy and efficiency.


Sujet(s)
Interprétation d'images assistée par ordinateur , Traitement d'image par ordinateur , Imagerie multimodale , Encéphale/imagerie diagnostique , Humains
5.
Microsc Res Tech ; 82(2): 75-84, 2019 Feb.
Article de Anglais | MEDLINE | ID: mdl-30351518

RÉSUMÉ

Seed shape, surface cells shape, arrangement, anticlinal wall pattern, and periclinal wall protuberances were recorded for nine species of Eucalyptus (Myrtaceae) using scanning electron microscopy to determine the importance of seed morphological characters as an additional tool for identification. Most of the seeds were found ovate and some seeds were elliptic and cuboid in shape. Almost reticulate regular seed surface patterns were observed. Four types of surface cells were examined; diamond, elliptic, oblong, and irregular. Majority of the seeds showed raised anticlinal wall level and diversity from wavy to puzzle in pattern. Periclinal wall may be glabrous or having protuberances that were rhombus and bullate in shape. Both macro- and micromorphological characters can provide basis for classification and delimitation of genus Eucalyptus. RESEARCH HIGHLIGHTS: Seeds quantitative characters of nine Eucalyptus species as seed length, width, and weight. Macromorphological characters of seeds including seed color, helium position, and seed shape. Micromorphological characters include seed surface, periclinal wall, and anticlinal wall investigation under scanning electron microscope. Ultra-seed sculpturing features as an additional tool in identification.


Sujet(s)
Eucalyptus/anatomie et histologie , Eucalyptus/ultrastructure , Graines/anatomie et histologie , Graines/ultrastructure , Microscopie électronique à balayage
6.
Microsc Res Tech ; 82(2): 114-121, 2019 Feb.
Article de Anglais | MEDLINE | ID: mdl-30575188

RÉSUMÉ

Current research carried out in Pakistan is the first report on spermoderm ornamentation of eight species of tribe Acacieae (Mimosoidae) by using scanning electron microscopic techniques representing two genera, Fedherbia and Acacia were examined. Different spermoderm ornamentation were observed, described and discussed for their taxonomic importance. Seeds surfaces of the studied tribe possess novel variations in macro and micro morphology. Great variations were observed in both qualitative and quantitative characters of seeds. Seeds shape was oblong, ovate to elliptical and spermoderm ornamentation was levigate, rugose, polygonal and discoid, colliculate, and papillose type. These variations in the spermoderm ornamentation can be used as an aid in identification and classification of the members of tribe Acacieae.


Sujet(s)
Acacia/anatomie et histologie , Acacia/ultrastructure , Variation intra-population , Graines/anatomie et histologie , Graines/ultrastructure , Acacia/classification , Microscopie électronique à balayage , Pakistan , Graines/classification
7.
J Med Imaging Radiat Sci ; 47(2): 178-193, 2016 Jun.
Article de Anglais | MEDLINE | ID: mdl-31047182

RÉSUMÉ

A lot of research has been done during the past 20 years in the area of medical image registration for obtaining detailed, important, and complementary information from two or more images and aligning them into a single, more informative image. Nature of the transformation and domain of the transformation are two important medical image registration techniques that deal with characters of objects (motions) in images. This article presents a detailed survey of the registration techniques that belong to both categories with detailed elaboration on their features, issues, and challenges. An investigation estimating similarity and dissimilarity measures and performance evaluation is the main objective of this work. This article also provides reference knowledge in a compact form for researchers and clinicians looking for the proper registration technique for a particular application.

8.
Environ Monit Assess ; 186(12): 8741-63, 2014 Dec.
Article de Anglais | MEDLINE | ID: mdl-25297711

RÉSUMÉ

Delineating areas susceptible to contamination from anthropogenic sources form an important component of sustainable management of groundwater resources. The present research aims at estimating vulnerability of groundwater by application of DRASTIC and Pesticide DRASTIC models in the southern part of the Gangetic plains in the state of Bihar. The DRASTIC and Pesticide DRASTIC models have considered seven parameters viz. depth to water level, net recharge, aquifer material, soil material, topography, impact of vadose zone and hydraulic conductivity. A third model, Pesticide DRASTIC LU has been adopted by adding land use as an additional parameter, to assess its impact on vulnerability zonation. The DRASTIC model indicated two vulnerable categories, moderate and high, while the Pesticide DRASTIC model revealed moderate, high and very high vulnerable categories. Out of the parameters used, depth to water level affected the vulnerability most. The parameter caused least impact was topography in DRASTIC, while in case of Pesticide DRASTIC and Pesticide DRASTIC LU models, the parameter was hydraulic conductivity. A linear regression between groundwater NO3 concentrations and the vulnerability zonation revealed better correlation for Pesticide DRASTIC model, emphasising the effectiveness of the model in assessing groundwater vulnerability in the study region. Considering all three models, the most vulnerable areas were found to be concentrated mainly in two zones, (i) in the south-western part along Ekangarsarai-Islampur patch and (ii) around Biharsharif-Nagarnausa area in the central part. Both zones were characterised by intensive vegetable cultivation with urban areas in between.


Sujet(s)
Agriculture , Surveillance de l'environnement/méthodes , Nappe phréatique/composition chimique , Modèles chimiques , Pesticides/analyse , Polluants chimiques de l'eau/analyse , Pollution de l'eau/statistiques et données numériques , Inde , Sol/composition chimique , Alimentation en eau/statistiques et données numériques
9.
Environ Monit Assess ; 184(4): 2321-36, 2012 Apr.
Article de Anglais | MEDLINE | ID: mdl-21611844

RÉSUMÉ

The present study has been carried out to assess groundwater quality in parts of Hindon-Yamuna interfluve region of western Uttar Pradesh. Fifty-five groundwater samples were collected from hand pumps in post-monsoon 2005 and pre-monsoon 2006 period, respectively, covering an area of about 1,345 km(2). Physical and chemical parameters of groundwater such as electrical conductivity, pH, total dissolved solid, Na, K, Ca, Mg, HCO(3), Cl, and SO(4) were determined. Concentration of the chemical constituents in groundwater of the study area varies spatially and temporarily. Interpretation of analytical data of major ion chemistry helps to identify three chemical types of groundwater i.e. 'mixed', 'mixed bicarbonate' and 'alkali bicarbonate' types. The species likely to occur in groundwater of the study area are Ca-HCO(3), Mg-HCO(3), Ca-SO(4), Na-Cl, Na-SO(4), Na-HCO(3), K-Cl, and some other possible species of K, depending on its abundance. The groundwater of the study area comes under the category of moderately hard to very hard, mildly acidic to slightly alkaline in nature. There is anomalously high concentration of major ions, particularly, Na, K, SO(4), and Cl. High SO(4) and K values may be related to anthropogenic influences, rather than through some natural process. Sodium along with Cl may be added to the system through sewage pollution and leachate percolation.


Sujet(s)
Nappe phréatique/composition chimique , Métaux lourds/analyse , Surveillance de l'environnement/méthodes , Inde
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