The extracellular matrix (ECM) is a meshwork of proteins and carbohydrates that supports many biological structures and processes, from tissue development and elasticity to preserve the structures of entire organs. In each organ, the composition of the ECM is distinct. It is a remarkably active three-dimensional structure that is continuously undergoing remodeling to regulate tissue homeostasis. This review aims to explain the role of ECM proteins in the remodeling process in different types of disease. The hardening of the ECM (desmoplasia), as well as its manipulation, induction, and impairment in regulation of its composition can play a role in several diseases, examples of which are chronic obstructive pulmonary disease, pancreatic ductal adenocarcinoma, spinal cord injury, progression and metastasis of breast cancer, and neurodegenerative condition in the brain such as Alzheimer's disease. Remodeling is also associated with diet-induced insulin resistance in many metabolic tissues. A greater comprehension of the way in which the ECM regulates organ structure and function and of how ECM remodeling affects the development of diseases may lead to the improvement and discovery of new treatments.

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Recently, mobile phones have become a potent vector for the transmission of pathogens. In hospitals, the use of the mobile phones by healthcare workers in an unhygienic manner accelerates the spread of nosocomial infection. We aimed to investigate the prevalence of microbiological contamination of mobile phones belonging to clinicians in Bangladesh hospitals. From 100 samples, we identified 69 isolates of bacteria including 22 Staphylococcus aureus; 11 Pseudomonas aeruginosa; 14 Escherichia coli; 6 Salmonella typhi 6 and 16 Staphylococcus epidermidis. On the basis of antibiotic susceptibility test using 11 antibiotics, it has been observed that most of the isolated bacteria became resistant to antibiotics and compared to other isolates, isolates of S. epidermidis and S. typhi were more resistant and sensitive, respectively. About 68.8% isolates showed that their resistance capacities against ampicillin but in contrast, 56.6% isolated were susceptible to imipenem. Azithromycin and imipenem against S. aureus, gentamicin against P. aeruginosa, tetracycline and imipenem against E. coli, tetracycline against S. typhi, and S. epidermidis revealed significant antimicrobial affectivity. We found that mobile phones are potential vectors to spread antibiotic-resistant nosocomial pathogens. Based on the study, an effective disinfection practice for cellular phones used in hospitals should be introduced to prevent the potential of cross-contamination.

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Introduction: Enamel is one of the most important structures of the tooth, both functionally and aesthetically. Because of the highly mineralized nature of enamel, its structure is difficult to study under routine light microscopy. Since scanning electron microscopy (SEM) offers the possibility of studying structures under very high magnification without altering the gross specimen, it is one of the best methods to study the enamel surface. Aims and Objectives: To study and compare the surface morphology and morphometry of enamel on various surfaces of permanent dentition. Materials and Methods: A total of 20 permanent teeth were analyzed under the SEM. In both anterior and posterior teeth, four surfaces – mesial, distal, labial, and lingual – in three thirds – cervical, middle, and incisal – were studied. In addition, the occlusal surface was also studied for the posterior teeth. The different prism morphology and prism dimensions were recorded. Results: Based on our observations, we could definitely identify striae of retzius, debris, and cracks under ×50 magnification. Three morphological patterns of prism arrangement were identified: Type 1 - shallow prisms, Type 2 - well-defined prisms, Type 3 - microporosities, on analyzing the mesial, distal, labial, lingual, and occlusal surfaces of the permanent teeth, at ×3000 magnification. The prisms were measured under ×6000 magnification and the results showed larger prisms in posterior than in anterior teeth. Conclusion: The study aided us in categorizing the enamel prism structure based on morphology and morphometry in anterior and posterior teeth of the permanent dentition.

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Introduction: Toxoplasma gondii, a common parasitic infection, has a special affinity to the brain. It has a lifelong existence without an apparent clinical disease. While the etiology of bipolar disorder (BD) remains unclear, epidemiological studies suggest a role for infections. Central nervous system is particularly susceptible to oxidative stress (OS) because of its high metabolic rate and its low levels of antioxidant defenses. OS is a contributor to the initiation and progression of many neurological illnesses. OS injury is a constantly and compelling finding associated with BD and toxoplasmosis. Aim: This cross-sectional study has investigated a possible role of toxoplasma-induced OS in the development of BD. Methods: Healthy controls and BD patients were examined for anti-Toxoplasma immunoglobulin-G (IgG) and two protein (3-nitrotyrosine) and DNA (8-hydroxy-2' deoxyguanosine [8-OHdG]) OS markers. Results: Toxoplasma positivity was higher (40%) among BD patients compared to controls (12%). Significantly higher levels of anti-Toxoplasma IgG were detected in BD patients compared to controls. Nitrotyrosine (796.7 ± 106.28) and especially 8-OHdG (20.31 ± 8.38) were significantly higher among toxo-positive BD compared to toxo-negative BD (675.97 ± 144.19 and 7.44 ± 2.86) and healthy controls (464.02 ± 134.6 and 4.17 ± 1.43). Conclusion: These findings might indicate a role for Toxoplasma infection in the development of BD, possibly through creating a highly oxidative brain environment.

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Ajwa dates (Phoenix dactylifera), cultivated particularly in Al-Madina Al-Monawarh in Saudi Arabia, and considered as a rich source of natural antioxidants such as anthocyanins, carotenoids and phenolics. It is believed that Ajwa dates have a wide range of protective effects. For this reason, this work aimed to investigate the ameliorative effect of Ajwa dates aqueous extract against ochratoxin A (OTA)-induced testicular lesions in rats. Rats were divided into four groups and treated for 28 days. Group I served as normal control, group II (OTA exposed) treated orally with 289 μg/kg/day. Group III (Ajwa dates aqueous extract) treated orally with 1 g/kg/day. The last group served as the protective group (pretreated with Ajwa dates extract, then OTA). Histological studies revealed that OTA induced lesions in the testicular structure included proliferation of sertoli cells, impairment of some spermatogenesis stages and accumulation of premeiotic germinal cells. However, pretreatment with Ajwa dates extract prevented all the testicular damage and improved spermatogenesis, as well as remarkably enhanced the testicular structure. In conclusion, Ajwa dates aqueous extract has a powerful protective effect and ameliorative influence against OTA- induced testicular damage and may be used to treat sexual impairment and male infertility.

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Background: Salivary sheaths, also known as stylet sheaths or stylet tracks, are essential features of the piercing-sucking feeding mechanism of plant-feeding hemipteran insects, many of which are vectors of economically important plant viral and bacterial pathogens. Although knowledge of their structure and function is incomplete, these salivary sheaths are frequently used by researchers to study hemipteran's feeding behavior, host preference, or host resistance, because these sheaths remain in the plant tissues after the insect withdraws its stylets following its feeding or probing on these tissues. However, in most cases, it is not known how long these salivary sheaths may last in plant tissues after their deposition by the feeding insects. An earlier report suggested that the salivary sheaths of the Asian citrus psyllid, Diaphorina citri (Hemiptera, Liviidae), vector of the devastating huanglongbing (citrus greening) disease bacterium, start to dissipate 1 week after their deposition in citrus leaves. Methods and Results: Here, using epifluorescence microscopy of cross sections in citron leaves, we found that D. citri salivary sheaths show signs of degradation in 3–4 weeks and become mostly degraded by 5–6 weeks, following their deposition by the psyllids into citrus tissues. Degradation of the salivary sheath starts at or near the “flange” area close to the leaf surface and continues gradually inward through the intercellular part of the sheath, within the mesophyll tissue, but apparently does not extend to the deeper or intracellular parts of the sheath in or near the phloem. Staining citron leaf sections with the fluorescent stain calcofluor white, which stains fungi, or propidium iodide (DNA/RNA stain) suggested that the degraded parts of the older salivary sheaths are not associated with fungi or bacterial accumulations. Conclusion: We speculate that degradation of the salivary sheaths may be due to enzymatic activities in the host plant, especially in the extracellular matrix of the mesophyll tissue.

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Background: Document examiners are frequently asked to determine whether or not a printout has originated from a particular laser printer. The printer can rarely be identified unless some unique defects or irregularities of the printer are present on the printout. Aim/Objective: The project aimed at obtaining the individual identification of printing and copying devices. Material and Methods: This paper presents an overview of a systematic approach to characterizing and discriminating the toner of different laser printer cartridges using scanning electron microscopy. A total of 21 collected printouts were printed on 21 different Lexmark printing machine models. Sixteen printouts were obtained using printers with original toner cartridges, while fi ve printouts were obtained using printers with replacements. Clear criteria were established for individual assessment. Results: Based on the SEM images and established criteria, the details of topography of the toner structure were revealed. Based on this study, the differences or similarities of toners on tested printouts were determined. Conclusion: The SEM technique can be successfully, simply, and rapidly applied to the analysis of toners on paper documents.

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