Search results for “Microscopy

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21 articles

Diagnostic Performance of Smear Microscopy and Xpert MTB/RIF Versus MGIT Culture in Republic of Congo

Nov 2025 DOI 10.14302/issn.2690-4721.ijcm-25-5786
Ornelle Elion Assiana DarrelCorresponding author

In the Republic of the Congo, tuberculosis (TB) remains a major public health concern. Although the GeneXpert MTB/RIF assay is the WHO-recommended first-line diagnostic test, smear microscopy is still used for treatment monitoring and in facilities where molecular testing is limited. Evaluating the diagnostic accuracy of smear microscopy compared to GeneXpert and MGIT culture is essential to guide diagnostic strategies and strengthen TB control in the country. A cross-sectional study was conducted among 92 presumptive pulmonary TB patients at Makelekele Hospital. Sputum samples were analyzed by smear microscopy, GeneXpert MTB/RIF, and MGIT culture. Sensitivity, specificity, positive and negative predictive value were calculated for smear microscopy and GeneXpert, using culture as the reference standard. Culture detected more Mycobacterium tuberculosis than microscopy (49% vs. 32%, P<0.001). Smear microscopy showed a sensitivity of 58% (95% CI: 43–71%) and specificity of 92% (95% CI: 80–97%). GeneXpert detected more MTB (62% vs. 49%, P<0.001) with a sensitivity of 98% (95% CI: 89–100%) and specificity of 72% (95% CI: 58–83%). GeneXpert showed superior sensitivity for TB detection, while microscopy remained specific. Expanding GeneXpert testing across the Republic of the Congo will improve TB management.

Bone Tissue Repair During Implantation of Titanium Nickelide Mesh: Scanning Electron Microscopy and X-Ray Electron Probe Microanalysis Observation

Aug 2018 DOI 10.14302/issn.2640-6403.jtrr-18-2158
Irianov Yu.M.Corresponding author Russian Ilizarov Scientific Center for Restorative Traumatology and Orthopedic, Russia

Purpose of Study: To study reparative osteogenesis and tissue integration characteristics for implanting three-dimensional mesh structures of titanium nickelide into a bone cavitary defect. Material and Methods: The authors modeled cavitary defects of femoral metaphysis experimentally in Wistar rats divided into an experimental group and control one. The study duration was 60 days in total. The methods of radiography, those of light and electron microscopy, X-ray electron probe microanalysis used. Results: Under implantation the defect was filled with cancellous bone the volumetric density of which more than 1,5-fold exceeded control values (р < 0.001). The implant had biocompatibility, osteoconductive and osteoinductive properties, it stopped inflammatory processes. The membrane protective barrier which prevented connective tissue sprouting was formed on the implant surface in the defect periosteal zone. The osteointegrative junction was formed being persisted up to the end of the experiment. Reparative osteogenesis was performed by direct intramembranous and apposition type. Conclusion: The implant of three-dimensional mesh titanium-nickelide structures has marked osteoplastic properties, and it can be successfully used in orthopedic surgery.

Comprehensive Study of Structural, Optical and EPR Properties of Mn2+ Doped CdSe Nanocrystals

Aug 2023 DOI 10.14302/issn.2377-2549.jndc-23-4461
Kripal RamCorresponding author

The synthesis of II-VI semiconductor nanocrystals doped with transition metal ions is particularly difficult. In the case of manganese doped CdSe nanocrystals produced via chemical route it is necessary to achieve small incorporation of manganese ions. The incorporation of manganese ions in CdSe nanocrystals has been confirmed by the study of Energy Dispersive Spectroscopy, Photoluminescence and Electron Paramagnetic Resonance spectra. The CdSe nanocrystals have cubic structure, the average crystallite size lies between 3-6 nm and increases with the variation of doping concentration of Mn2+ ions as characterized by X-ray diffraction. The structural properties of CdSe semiconductor nanocrystals are also studied by High Resolution Transmission Electron Microscopy, Scanning Electron Microscopy and UV- Visible Absorption Spectroscopy. The energy band gaps have been determined by UV/V is absorption study with the help of Tauc plot and are 2.54 eV, 2.27 eV and 2.24 eV as concentration of Mn2+ions in CdSe semiconductor nanocrystals increases from 0% to 0.75%. The crystallite size is also obtained from the UV-Visible absorption study; this varies from 1.69 to 1.78 nm with increase of Mn2+ concentration from 0% to 0.75% which is in agreement with X-ray diffraction result. Further, the magnetic and electronic properties of Mn2+ doped CdSe nanocrystals are studied using EPR spectra and the values of g factor, second-rank axial zero-field splitting parameter D and hyperfine parameter A are calculated. EPR measurements reveal that the dopant ions are incorporated in CdSe semiconductor nanocrystals.

Research Gaps In Contaminants Of Emerging Concern (CECs): Routes To The Standardization Of Chemical Test Methods By GC/LC-Mass Spectrometry: A Review

Jun 2023 DOI 10.14302/issn.2377-2549.jndc-23-4615
Manickum ThavrinCorresponding author

A literature review was undertaken with a focus on 1) identifying the research gaps regarding CECs, 2) identifying the most common ones, and 3) identifying the typical analytical methods/technologies employed, for their analysis. A total of 214 papers were noted, with a total of 21 review articles (9.8%). Of this total, a surprisingly high number were from South Africa alone: 117 (54.7%), of which 44 (20.6%) reports were associated with South Africa’s Water Research Commission (WRC). The top three CECs research gaps were (decreasing rank: Number of “gaps”, %): 1) Toxicity/Risk/Impact (260, 21.5%), 2) Analysis/Tests/Methods (118, 9.8%) and 2) Future research/studies (118, 9.8%), and 3) Monitoring (89, 7.4%). The common classes of CECs that were reported on, were : (i) Chemical: pharmaceuticals, personal care products, steroids, chlorinated and brominated contaminants, PAHs, PCBs, phthalates, alkyl phenols, herbicides, organochlorine pesticides, engineered nanomaterials and (ii) “Microbiological”: antibiotic resistance genes, human enteric bacteria and viruses, microbial pathogens (e.g., E Coli, rotavirus, Crypto, etc.), infectious biological water contaminants (e.g., E Coli isolates), cyanobacterial blooms (Microcystis). Common test methods used for analysis of the chemical contaminants were found to be chromatography (gas, liquid)-mass spectrometry; for the microbial contaminants, they were culture-based methods, ELISA, fluorescence microscopy, qPCR, RT-qPCR, gel electrophoresis, Raman spectroscopy, and also chromatography (largely liquid)-mass spectrometry, were also used. Some proposals were additionally made to address the very common, significant research gaps noted in CECs research, especially the standardization of analytical chemical test methods, based on chromatography-mass spectrometry, for quantification.

Production of biodegradable polymer via graft copolymerization of gum Arabic and polyethylene glycol

Jun 2023
Rifkatu Kambel DogaraCorresponding author

The increasing demand for environmentally-friendly materials has led to a surge in research on the production of biodegradable polymers. In this study, we investigate the synthesis of a biodegradable polymer by graft copolymerization of gum Arabic (GA) and polyethylene glycol (PEG). GA, a natural polysaccharide and PEG, a synthetic water-soluble polymer, were used as the backbone and graft monomer, respectively. The graft copolymerization was carried out using benzoyl peroxide as an initiator and performed under nitrogen atmosphere. The resulting polymer was characterized by Fourier transform infrared (FTIR) spectroscopy, Xray diffraction (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The FTIR spectra confirmed the formation of the graft copolymer, and TGA analysis showed that the copolymer had higher thermal stability than GA. The DTA thermograms indicated two thermal events. The evaporation of water and organic polyethylene glycol components was measured, and the first mass loss was due to the loss of adsorbed and structural water in the gum Arabic, which occurred between 31.87 and 180°C, while the second, corresponding to the pyrolysis of polyethylene glycol functional groups and polysaccharide decomposition, resulted in a 70% mass loss. SEM morphological analysis of gum Arabic showed aggregates of high irregularity in particle shape. The cracks and holes obtained in the Gum Arabic micrograph disappeared from the new gum Arabic-graft-polyethylene glycol, leaving a smooth surface with scattered particles in the image, which was due to the grafting copolymer. From the XRD patterns, the percentages of the amorphous and crystalline phases were determined. The results show that gum Arabic has a 78% degree of crystallinity, whereas gum Arabic-graft-polyethylene glycol has the lowest value of 51%. Biodegradation activity was observed using the fungus Aspergillus flavus on different days on gum Arabic-g-polyethylene glycol. The results clearly showed inhibition zones with a change in the state of the copolymer from solid to liquid from days 8 to 14. These results indicate that the GA-PEG copolymer has potential as a biodegradable material for use in various applications, such as packaging, agriculture, and medical industries.

Thin Film Deposition and Characterization Techniques

Apr 2022 DOI 10.14302/issn.2831-8846.j3dpa-22-4066
Geremew TemesgenCorresponding author Debark University, Department of physics, Debark, Ethiopia

Thin films are everywhere in the modern world, with many of the technologies we depend upon in daily life being, in turn, dependent upon thin film technology. Chemical bath deposition includes principles of chemical bath deposition (CBD) and concept of solubility product, nucleation and film growth, thin film deposition mechanism in chemical bath deposition. The non-metallic ion source (anions) and metal ion source (cations) then react to form the compound. The nucleation process plays an important role in determining the crystallinity and microstructure of the resultant film. From the discussion of deposition techniques which are physical and chemical deposition methods. Physical deposition techniques contains sputtering deposition, electron beam evaporation and physical vapour deposition (PVD) process have been known for over 100 years and also fabrication films on the substrate, as well as the increasement of the pressure in the chamber due to operation of the sources indicates directly that gases or vapors are desorbed. Chemical deposition process is economically effective and has been industrially exploited to large scale. It can be summarized that thin film characterization techniques include X-ray diffraction (XRD), UV-Vis spectrophotometer, scanning electron microscopy, energy dispersive x-ray diffraction, transmission electron microscopy (TEM). X-rays diffraction (XRD) is a rapid and a powerful technique used to study the phase of a crystalline material, information on unit cell lattice parameters, crystal structure, crystal orientation and crystalline size.

Evolution of the Solid Human Tumor Cells Properties in Various Experimental Systems in Vitro

Jan 2022 DOI 10.14302/issn.2372-6601.jhor-22-4061
B. Danilova AnnaCorresponding author N.N. Petrov National Medicine Research Center of Oncology, Department of Oncoimmunology, 197758, Leningradskaya str., 68, Pesochny, Saint-Petersburg, Russian Federation

Background Human malignant cell models which reflect the structural and physiological complexity of tumor tissue are of great importance for preclinical research in oncology. Spheroids/tumoroids derived from solid tumors are of great interest as cellular models mimicking the first vascular-free growth phase of a tumor node. The fact of the identity between artificially created tumor multicellular aggregates and the real tumor tissue, however, needs to be specified, described and validated in order to see how closely the spheroids are biologically similar to the malignized tissues in vivo compared to the monolayer cell cultures traditionally used. We present here a comparison study of the characteristics of solid tumor cells of different histogenesis (melanomas, soft tissue sarcomas and bone sarcomas, epithelial tumors) cultured in two dimensions (monolayer culture) and three dimensional space (spheroid), namely: spatial organization, multiplication, metabolic activity. Patients and Methods For the creation of 2 D and 3D cell models the cells isolated from the patient's solid tumor fragments obtained intraoperatively were used. 15 samples of skin melanoma, 20 samples of soft tissue and osteogenic sarcomas (STBS), and 9 samples of epithelial tumors (ET). The tumor cells were all cultivated for at least 10 passages. We used phase contrast, confocal microscopy, and immunohistochemistry to investigate spheroids and monolayer cultures. The supernatants of tumor cells grown in 2D and 3D cultures were studied using ELISA and multiplex analysis for the production of a spectrum of chemokines and cytokines supporting the immunosuppression, invasion and metastasis processes. Results Tumor specimens received were predominantly of metastatic origin (75%). In 100% of cases 2D cultures were received, in 88.6% of cases (39 out of 44) we succeeded in obtaining spheroids. There was no direct correlation between the efficiency of tumoroid formation and the tumor's histogenetic origin and the stage of the cancer process (primary tumor, recurrence, metastasis). The median size of spheroids by 4-5 days of cultivation with a starting concentration of 10000 cells per well was 657.14 μm for melanoma (min 400 - max 1000 μm), 571.42 μm (min 400 - max 700 μm), 507.14 μm (min 300 - max 600 μm) for soft tissue sarcomas, 650.0 μm (min 400 - max 900 μm) for osteogenic sarcomas. Immunochemical analysis of Ki-67, GLUT1, and Ecadherin markers was carried out for tumor tissue samples, single-layer tumor cultures, and tumoroids of every patient. The distribution of the stained groups in the spheroids was distinct from the monolayer cultures and more in accordance with the distribution of such in the tissue tumor, the number of Ki-67+ cells was increasing in the spheroids. We detected no dependence of Ki-67+ and GLUT1+ cell localization grade on spheroid size. We identified E-cadherin in tumor tissue and tumoroids of breast carcinoma and one melanoma culture. Monolayer cultures did not express it. The increase in secretory cell activity of the solid tumor cells from 2D to 3D system was observed when CCL2, CCL3, CXCL1, CXCL16, MIF, IL10, MICA (p<0.01) were investigated. Conclusion The presence of patient-specific cells of solid tumors in a 3D environment causes activation of the proliferative and metabolic processes as compared to monolayer cultures, which makes these models approximate the real world clinical picture. The production of chemokines that can attract to the tumor various types of immune system cells, to include their immature versions, as well as production of cytokines and Immunosuppression factors that, when present in the tumor microenvironment in the high concentrations, contribute to the formation of immune cells having suppressive capacities occurs in the 3D cell system. Three-dimensional model of the initial tumor nodule formation stage thus demonstrates the forming process of tumor cells favorable for them microenvironment. Construction of three-dimensional models - spheroids of tumor cells of differing histogenesis demands individual approach and more thorough investigation.

Communicating Branch of the Mental Nerve and Facial Nerve

Mar 2021 DOI 10.14302/issn.2577-2279.ijha-21-3769
Hirouchi HidetomoCorresponding author Department of Anatomy, Tokyo Dental College, 2-9-18 Kandamisaki-cho. Chiyoda-ku, Tokyo, Japan.

As peripheral branches of the mandibular nerve, the mental nerve and facial nerve communicate with each other. However, investigations have not always been described in the classic anatomical texts. It remains unknown how nerve fibers of this communicating branch converge at the micro level. Thus, the objective of the present study was to observe in detail the macro and micro levels of the communicating branch of mental and facial nerves. We used five cadavers (10 samples) to conduct experiments in anatomical practice at Tokyo Dental College. A macroscopic observation was made, and the communicating branch of the mental and facial nerves was removed as a single mass. We created serial sections of this branch using the standard method and observed communicating branches of these two nerves under microscopy. As a result, the communicating branch of the mental and facial nerves was completely fused at the perineurium level. It has been reported that the mental nerve includes a small amount of autonomic nerve fiber. As for these findings, similar findings were observed for all 5 bodies and 10 sides. Thus, we believe that autonomic nerve fibers derived from the facial nerve converge with the mental nerve via this communicating branch.

Preparation of Microwave Multi-Adsorbent Nanocomposites Based on Copper, Iron Carbonyl, Carbon Nanofiber, Graphite Nanoflake and Polypyrrole

Nov 2020 DOI 10.14302/issn.2689-2855.jan-20-3616
Hossien Hosseini SeyedCorresponding author Department of Chemistry, Faculty of Science, Islamshahr Branch, Islamic Azad University, Tehran, Iran, Nika Pooyesh Strategic Sciences Research Institute, NBP Economic Group, Tehran-Iran

The composites of Cu, Carbonyl iron (CI), carbon nanofiber (CNF), graphite nanoflake (GNF)/polypyrrole (PPy) and [(Cu-CI-CNF-GNF) 0.5-PAA]-PPy0.5 were synthesized via different methods by in-situ polymerization on the surface of nanoparticles (NPs) with core-shell structure. This paper describes a method for polyacrylic acid (PAA) coating of NPs in aqueous solution. Then PPy coating was performed by template polymerization on NPs-PAA. Morphology, magnetic and conductivity properties were observed via scanning electron microscopy (SEM), vibrating sample magnetometer (VSM) and four probe method, respectively. The microwave characterization of nanocomposite was evaluated through arch test based on a network analyzer. The PPy nanocomposites possessed the excellent microwave multi absorbers properties in 2-18 GHz. It was also found that nanocomposites with 50% w/w and light weight exhibit good microwave absorbing properties in 2-3 GHz and 5-14 GHz frequency, so can be used to cellphone, radio frequency and radar shielding.

Study of the Nanocomposite cBN/TiC-SWCNTs by Field Actived Sparck Plasma Sintering Process

Mar 2020 DOI 10.14302/issn.2689-2855.jan-20-3243
Bendjemil BadisCorresponding author DGM, FST, University of 8 Mai 1945 of Guelma, 24000 Guelma, Algeria

Cubic boron nitrid (cBN) bonded TiC and alloyed with single walled carbon nanotubes (SWCNTs or NC) ceramics matrix nanocomposites (CMNCs) tools were manufacturated by a field actived sparck plasma sintering processus (FASPS). The effects of cBN-TiC ratio, carbon nanotubes and optimisation of the sintering process on the microstructure, densification in addition mechanical and vibronic properties of NC-cBN-TiC nanocomposites were studied. The results showed that for the nanocomposite cBN-TiC vol. ratio of 8:2 with 0.1 wt% NC, it was found that microhardness incresses significantly with addition of carbon nanotubes exhibited the highest microhardness and fracture toughness. After sintering of the samples at 1800 °C, 10 mn, 75 MPa of cBN–TiC1-x, x=0.8 with and without addition of 0.1 wt% NC were characterized using field emission scanning electron microscopy (FESEM) and X-ray diffraction. The samples exhibited a dense polycrystalline structure. From the resonant Raman scattering we can locate the vibration frequency of the transformation cBN to hexagonal boron nitrid (hBN) and formation of secondary hard phase TiB2to consolid the (CMNCs) tools. The final product is hBN-TiC-TiB2-NC.The best product contained cBNx-TiC1-x (x=0.8)-0.1 wt % NC which was sintered at 1800 °C, 75 MPa for 10 mn. The Vickers hardness of cBN-TiC1-x (x=0.8) incresses with NC incorporation in the matrix The indentation fracture toughness was calculated to be 12.30 MPa m1/2 for cBNx-TiC1-x (x=0.8 -0.1 wt % NC ceramics matrix nanocomposite (CMNCs) tools with excellent wear resistant will be confirmed. The wear of cBN-TiC of the composites tools have shown that this is predominantly a chemical process involving the interaction of the tool with its environment and is restricted by the formation of protective layers on the exposed faces of the tool by the addition of carbon nanotubes (NC). The wear features of tools used in fine cutting tests under identical conditions will be compared and the results will be interpreted in terms of the existing models for the wear of cBN -based nanomaterials by the effects of the additives in the modified tools

Parasite Research Open Access

Malaria and Typhoid Fever Coinfection in the Hospital University of Bobo-Dioulasso, Burkina Faso

Dec 2019 DOI 10.14302/issn.2690-6759.jpar-19-3081
Ibrahim SangaréCorresponding author Institut Supérieur des Sciences de la Santé, Université Nazi BONI, Bobo-Dioulasso, Burkina Faso

Malaria and typhoid fever are two endemic infectious diseases in developing tropical countries including Burkina Faso. There are two distinct infectious diseases with many similar clinical signs. In each sanitary area, it is important to describe the "typhomalaria" epidemiology to elaborate adequate diagnosis algorithm and efficient treatment protocol. A cross-sectional study was carried out from July to October 2014 in the lab department of University Hospital Souro SANOU, Bobo-Dioulasso. All microscopy positive malaria during the study period was included. Serodiagnosis of Widal and Felix was performed systematically in all Plasmodium spmalaria cases. Titers of antibodies anti-agglutinin O equal or higher than 1/400 and/or 1/800 for anti-agglutinin H antibodies were considered positive for Salmonella sp. A total of 283 malaria cases were included in this study, majority falciparum malaria. In this malaria cases, 91 patients were seropositive for Salmonella sp. "Typhomalaria" co-infection prevalence was 34.3% (CI 95% (28.8%; 40.1%)). The patient with the normal hemoglobin rate had the highest prevalence of co-infection (46.7% versus 30.9; p=0.02). Malaria and typhoid fever co-infection was high (approximately 1/3 of malaria cases) in University hospital of Bobo-Dioulasso. This study revealed the need to explore typhoid fever in malaria confirmed cases, especially in persistent fevers and non-anemic situation despite adapting antimalarial treatment.

Chondroplasty Efficacy of Bone Matrix

Dec 2019 DOI 10.14302/issn.2577-2279.ijha-19-3110
N.A. KiryanovCorresponding author Izhevsk State Medical Academy, Izhevsk, Russia

Aim To study the chondroplasty efficacy of the bone matrix obtained using an original technology in restoring cartilage defect of the knee joint. Material and Methods Marginal defects were modeled on the surface of the distal end of the femur in 40 adult male Wistar rats. The bone matrix obtained using an original technology was implanted in the damaged area in animals of the experimental group. Material was investigated by means of light microscopy, transmission and scanning electron microscopy, and electron probe X-ray microanalysis. Results It was found that the bone matrix implanted did not cause an immune rejection reaction, activated reparative chondrogenesis for a prolonged period. In the area of articular cartilage lesion, the regenerate acquiring cellular and histochemical characteristics of the hyaline cartilage tissue was formed. The chondroinductive properties for the bone matrix were ensured by localized growth factors and morphogenetic proteins released during osteoclastic resorption. Conclusion The application of the bone matrix as a stimulator of chondrogenesis is theoretically reasonable and has a good perspective in treatment of damages and diseases of the articular cartilage.

Haematuria in the Elderly: a Review

Jun 2019 DOI 10.14302/issn.2474-7785.jarh-19-2932
Dabota Buowari YvonneCorresponding author New Jerusalem Road, Bonny, Rivers State, Nigeria

Haematuria is a common compliant in the elderly. Microscopic haematuria is first suspected after a dipstick in urine and confirmed with urine microscopy. The causes of haematuria in the elderly may be renal or extra-renal including clotting disorders. This article is a review on haematuria in the elderly.

Morpho-Anatomical and Physicochemical Standardization of Diospyros malabarica (Desr.) Kostel Stem Bark

Jul 2018 DOI 10.14302/issn.2638-4469.japb-18-2166
Chandra Gupta PrakashCorresponding author University Institute of Pharmacy, Chhatrapati shahu Ji Maharaj University, Kanpur-208024, Uttar Pradesh India

Diospyros malabarica (Desr.) Kostel synonym Diospyros peregrina Gurke (Family: Ebenaceae) is a medium sized evergreen tree commonly known as Kendu in Assamese. The plant has ethnomedicinal significance and used by various ethnic communities of North-East India to treat various disorders like dysentery, diabetes, diarrhea malaria, ulcer and wounds. However, detailed scientific information is not available to identify the plant material, in order to ascertain its quality and purity. Therefore, the present work was carried out to perform morpho-anatomical and physicochemical analysis of D. malabarica stem bark. The bark is externally dark brown to black in color and rough having characteristics odor and astringent taste. The microscopy of bark reveals the presence of polygonal thick walled cork, 3-4 layered phellogen, 7-8 layered phelloderm, stone cells, phloem fibers and medullary rays. Stem bark powder showed thick walled cork cells, thick walled elongated phloem fibers, lignified stone cells and rhomboidal crystals of calcium oxalate. Further, physicochemical analysis of the bark power showed loss on drying, total ash, water soluble ash, and acid insoluble ash as 6.2, 5.6, 1.1, 2.45, and 5.7% w/w respectively. The alcohol and water soluble extractives values of the stem bark were 10.6 and 16.8% w/w respectively. The result of preliminary phytochemical screening indicates presence of triterpenoids, saponins, tannins, flavonoids and sterols. The findings of this study will facilitate pharmacognostic standardization of the plant material and aid in the preparation of an herbal monograph for the species.

Prospect of Graphene Interface Control for Tougher Ceramic Composites

Jun 2018
Kendall KevinCorresponding author University of Birmingham, B15 2TT, UK

Graphene-Ceramic Composites (GCCs) have been little studied compared to graphene-polymer composites 1. Recent reviews 23 indicate that both mechanical and electrical property ceramic improvements can be obtained by mixing small quantities, typically 1 to 15% of graphene material with a ceramic precursor, then compacting and sintering. The greatest effect is on the electrical properties. The electrical conductivity of a material was first shown to rise by several orders of magnitude for only a 1% volume addition of graphene as in polymer composites 4 but the stiffness, strength and toughness only increased by 20-160% or so at 5% addition, a rather minor improvement compared to significant increases caused by slight ceramic process changes. Some crack bridging and pull-out mechanism was observed by electron microscopy in graphene-alumina composites, though the effects were modest. Surface friction and wear improvements of around 100% were also notable. This paper seeks to show that much higher toughness increases might be produced using the method pioneered by Clegg et al 5, where the graphite interlayers are replaced with graphene to produce improved ordered interfaces with reliable coverage and consistent interface fracture energy, enabling an increase in the fracture resistance of the ceramic by two orders of magnitude.

The Effect of Laser Irradiation on Reparative Osteogenesis

Apr 2018 DOI 10.14302/issn.2577-2279.ijha-18-2030
A. Kiryanov N.Corresponding author Izhevsk State Medical Academy, Russia.

Introduction: The use of non-medicinal facilities for correcting processes in various pathological conditions is one of the most urgent problems of modern medicine. Purpose of the Work: To study the effect of low-intensity infrared laser radiation on reparative bone formation and angiogenesis in bone regeneration which is formed in treatment of fractures under conditions of transosseous osteosynthesis. Material and Methods: A tibia fracture was modeled experimentally in rats in the control and experimental groups. Reposition and fixation of fragments were performed. The fracture zone in the experimental group animals was exposed to the impact of pulsed infrared laser irradiation of low intensity. Animals from the control group underwent the impact simulation. The operated bones were investigated using the methods of X-ray, light and electron microscopy, X-ray electron probe microanalysis. Results: It was established that laser radiation exposure sessions activated fibrillogenesis and angiogenesis, accelerated compacting of newly formed bone tissue and increased its maturity while primary fracture healing occurred. Prolonged capillary dilatation and endothelium-dependent vasodilation, intensive capillarogenesis were noted after sessions of laser therapy in bone regeneration. Endothelial outgrowth was formed in the lumen of the vessels forming capillary buds that propagate along the “mother” vessels (endovascular capillarogenesis). Conclusion: The data obtained revealed a possible mechanism of laser radiation exposure at the level of a whole organism and proved the effectiveness of its application in clinical practice at the early stages of patient rehabilitation under conditions of transosseous osteosynthesis.

Experimental-Morphological Study of Reparative Bone Formation with The Replacement of The Cavity Defect of The Bone with A Mesh of Titanium Nickelide

Feb 2018 DOI 10.14302/issn.2577-2279.ijha-18-1918
Kiryanov N.A.Corresponding author Izhevsk State Medical Academy, Russia

Purpose of Study To study reparative osteogenesis and tissue integration characteristics for implanting three-dimensional mesh structures of titanium nickelide into a bone cavitary defect. Material and Methods The authors modeled cavitary defects of femoral metaphysis experimentally in Wistar rats divided into an experimental group and control one. The study duration was 60 days in total. The methods of radiography, those of light and electron microscopy, X-ray electron probe microanalysis used. Results Under implantation the defect was filled with cancellous bone the volumetric density of which more than 1,5-fold exceeded control values (р < 0.001). The implant had biocompatibility, osteoconductive and osteoinductive properties, it stopped inflammatory processes. The membrane protective barrier which prevented connective tissue sprouting was formed on the implant surface in the defect periosteal zone. The osteointegrative junction was formed being persisted up to the end of the experiment. Reparative osteogenesis was performed by direct intramembranous and apposition type. Conclusion The implant of three-dimensional mesh titaium-nickelide structures has marked osteoplastic properties, and it can be successfully used in orthopedic surgery.

Lysozyme-Induced Degradation of Chitosan: The Characterisation of Degraded Chitosan Scaffolds

Dec 2017 DOI 10.14302/issn.2640-6403.jtrr-17-1840
Rogina AnamarijaCorresponding author Faculty of Chemical Engineering and Technology, University of Zagreb

Up till now, chitosan has confirmed its versatile application in skin, cartilage and bone tissue engineering, as well as in drug delivery applications. This study is focused on enzymatic degradation of porous chitosan structures usually designed for mentioned purposes. In vitro degradation was monitored during four weeks of incubation at physiological temperature and in two different media, phosphate buffer saline solution and water. The scaffolds were characterised before and after enzymatic degradation using scanning electron microscopy and infrared spectroscopy with Fourier transformations (FTIR). According to the gravimetric analysis, higher weight loss of chitosan scaffolds was observed in buffered medium with respect to the water. The results implied that the total weight loss obtained in buffer involves physical dissolution of chitosan and lysozyme cleavage of glycoside bond. Importantly, FTIR identification of chitosan scaffolds after enzymatic degradation indicated the absence of lysozyme activity in water, indicating that weight loss is a result of the chitosan dissolution. This finding greatly impacts design of degradation experiments and characterisation of degradation behaviour of chitosan-based materials utilised as implants or drug delivery systems.

Performance Assessment of Some Operational Aspects of Revised National Tuberculosis Control Programme in Tuberculosis Unit, Nagpur, India

Feb 2017 DOI 10.14302/issn.2474-3585.jpmc-16-1103
M. Chaudhary SanjeevCorresponding author Associate Professor, Government Medical College,Gondia

Background : DOTS is the current international strategy for tuberculosis control endorsed by the World Health Organization and the International Union against Tuberculosis and Lung Diseases. Maharashtra achieved full coverage under RNTCP in October 2003. The programme was launched in Nagpur in the last quarter of 2002. Three years after its launch, it is the ideal time to assess the performance of programme to identify the operational challenges. Methods: This is a cross sectional study carried out in 'Sadar Tuberculosis Unit' of Nagpur Municipal Corporation with the objective to study performance of some aspects of RNTCP. Programme performance was explored through laboratory records review and non participant observations of all four designated microscopy centres. DOT centres were observed for accessibility, identifiability and the facilities provided to patients visiting for treatment. Performance of some operational aspects of RNTCP was assessed using standards, norms, procedures etc described in programme guidelines. Results: It was observed that the TB unit was manned with RNTCP- trained supervisory team. Three of four microscopy centres were established in multispecialty health facilities. Adequate space for sputum microscopy was available at two centres. Laboratory technician was available at three centres. Separate tables for smearing and staining were available at three centres. Sink, staining racks, spirit lamp, binocular microscope and drugs in patient - wise boxes were available in all four centres. Laboratory registers were completely and correctly filled in all centres. No false positive or false negative error was found in rereading of AFB smears. Conclusions: It is concluded that the performance of the programme at the unit is satisfactory. Still some aspects of the programme components need to be strengthened at microscopy centres for better performance of RNTCP.

Preparation and Application for Separation of Small Molecules of a New Poly(OVS-co-EDMA) Hybrid Monolithic Column

May 2016 DOI 10.14302/issn.2377-2549.jndc-15-923
Wang FengqingCorresponding author Key Laboratory of Pharmaceutical, College of Pharmaceutical Sciences, Hebei University, Baoding, 071000, P. R. China.

A hybrid monolithic column was prepared using octavinyloctasilasesquioxane (OVS) as a monomer, benzoyl peroxide/dimethylacetamide (BPO/DMA) as initiator, ethylene glycol dimethacrylate (EDMA) as cross-linker, 1-dodecanol as porogenic agent and dimethylbenzene as cosolvent. A tidy skeleton, much bigger specific surface area (22.4 m2/g) and lower swelling property of the monolithic column with OVS added than the one without OVS added were determined with Scanning Electron Microscopy (SEM), Nitrogen adsorption/desorption measurements (BET) and swelling test with elute of different concentration of acetonitrile in water. Fourier-transform infrared spectra (FTIR) was taken to characterize the composition of groups. Moreover, a better separation performance for benzene series compounds under reversed phase liquid chromatography (RPLC) mode was obtained using the monolithic columns with OVS added than those without.

Diagnostics of Progressive Multifocal Leukoencephalopathy in a Patient with Concomitant Lymphoma Infiltration of Central Nervous System During R-CHOP Chemotherapy- A Case Presentation and Review of the Literature.

Jun 2014 DOI 10.14302/issn.2372-6601.jhor-14-378
Kulma-Kreft MonikaCorresponding author Department of Radiotherapy and Medical Oncology, Gdynia Cancer Center, Gdynia

Progressive multifocal leukoencephalopathy (PML) is a rare complication associated, inter alia, with rituximab-based lymphoma treatment. PML diagnosis is made easier with the criteria recently published by the American Academy of Neurology. Unambiguous diagnosis of PML can be achieved by demonstration of the histopathological triad comprising:(1) demyelination, (2) bizarre astrocytes and (3) enlarged oligodendroglial nuclei together with detection of viral particles by electron microscopy. However, symptoms of PML may be similar to those observed during lymphoma progression into the central nervous system (CNS). Here we report the case of a patient with diffuse large B-cell lymphoma (DLBCL) treated with R-CHOP who developed clinical signs indicating PML. Intravital diagnostic methods failed to yield an unequivocal diagnosis of PML or lymphoma progression in the CNS. However, a post-mortem examination of brain biopsy specimens performed by electron microscopy demonstrated lesions typical for PML and the presence of viral particles. In addition, immunohistochemical assays identified a massive infiltration of lymphoma cells. The case thus suggests either the extremely rare coexistence of two complications: lymphoma CNS infiltration and PML or induction structural CNS lesions by lymphoma infiltration indistinguishable from PML. The presented findings thus highlight the need for a further review of the current diagnostic criteria for PML.

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