GelMA/TCP nanocomposite scaffold for vital pulp therapy

Pulp capping is a necessary procedure for preserving the vitality and health of the dental pulp, playing a crucial role in preventing the need for root canal treatment or tooth extraction. Here, we developed an electrospun gelatin methacryloyl (GelMA) fibrous scaffold incorporating beta-tricalcium phosphate (TCP) particles for pulp capping. A comprehensive morphological, physical-chemical, and mechanical characterization of the engineered fibrous scaffolds was performed. In vitro bioactivity, cell compatibility, and odontogenic differentiation potential of the scaffolds in dental pulp stem cells (DPSCs) were also evaluated. A pre-clinical in vivo model was used to determine the therapeutic role of the GelMA/TCP scaffolds in promoting hard tissue formation. Morphological, chemical, and thermal analyses confirmed effective TCP incorporation in the GelMA nanofibers. The GelMA+20%TCP nanofibrous scaffold exhibited bead-free morphology and suitable mechanical and degradation properties. In vitro, GelMA+20%TCP scaffolds supported apatite-like formation, improved cell spreading, and increased deposition of mineralization nodules. Gene expression analysis revealed upregulation of ALPL, RUNX2, COL1A1, and DMP1 in the presence of TCP-laden scaffolds. In vivo, analyses showed mild inflammatory reaction upon scaffolds' contact while supporting mineralized tissue formation. Although the levels of Nestin and DMP1 proteins did not exceed those associated with the clinical reference treatment (i.e., mineral trioxide aggregate), the GelMA+20%TCP scaffold exhibited comparable levels, thus suggesting the emergence of differentiated odontoblast-like cells capable of dentin matrix secretion. Our innovative GelMA/TCP scaffold represents a simplified and efficient alternative to conventional pulp-capping biomaterials. STATEMENT OF SIGNIFICANCE: Vital pulp therapy (VPT) aims to preserve dental pulp vitality and avoid root canal treatment. Biomaterials that bolster mineralized tissue regeneration with ease of use are still lacking. We successfully engineered gelatin methacryloyl (GelMA) electrospun scaffolds incorporated with beta-tricalcium phosphate (TCP) for VPT. Notably, electrospun GelMA-based scaffolds containing 20% (w/v) of TCP exhibited favorable mechanical properties and degradation, cytocompatibility, and mineralization potential indicated by apatite-like structures in vitro and mineralized tissue deposition in vivo, although not surpassing those associated with the standard of care. Collectively, our innovative GelMA/TCP scaffold represents a simplified alternative to conventional pulp capping materials such as MTA and Biodentine™ since it is a ready-to-use biomaterial, requires no setting time, and is therapeutically effective.

Nanoscale β-TCP-Laden GelMA/PCL Composite Membrane for Guided Bone Regeneration

Major advances in the field of periodontal tissue engineering have favored the fabrication of biodegradable membranes with tunable physical and biological properties for guided bone regeneration (GBR). Herein, we engineered innovative nanoscale beta-tricalcium phosphate (β-TCP)-laden gelatin methacryloyl/polycaprolactone (GelMA/PCL-TCP) photocrosslinkable composite fibrous membranes via electrospinning. Chemo-morphological findings showed that the composite microfibers had a uniform porous network and β-TCP particles successfully integrated within the fibers. Compared with pure PCL and GelMA/PCL, GelMA/PCL-TCP membranes led to increased cell attachment, proliferation, mineralization, and osteogenic gene expression in alveolar bone-derived mesenchymal stem cells (aBMSCs). Moreover, our GelMA/PCL-TCP membrane was able to promote robust bone regeneration in rat calvarial critical-size defects, showing remarkable osteogenesis compared to PCL and GelMA/PCL groups. Altogether, the GelMA/PCL-TCP composite fibrous membrane promoted osteogenic differentiation of aBMSCs in vitro and pronounced bone formation in vivo. Our data confirmed that the electrospun GelMA/PCL-TCP composite has a strong potential as a promising membrane for guided bone regeneration.

Multifunctional and biodegradable methacrylated gelatin/Aloe vera nanofibers for endodontic disinfection and immunomodulation

Currently employed approaches and materials used for vital pulp therapies (VPTs) and regenerative endodontic procedures (REPs) lack the efficacy to predictably achieve successful outcomes due to their inability to achieve adequate disinfection and/or lack of desired immune modulatory effects. Natural polymers and medicinal herbs are biocompatible, biodegradable, and present several therapeutic benefits and immune-modulatory properties; thus, standing out as a clinically viable approach capable of establishing a conducive environment devoid of bacteria and inflammation to support continued root development, dentinal bridge formation, and dental pulp tissue regeneration. However, the low stability and poor mechanical properties of the natural compounds have limited their application as potential biomaterials for endodontic procedures. In this study, Aloe vera (AV), as a natural antimicrobial and anti-inflammatory agent, was incorporated into photocrosslinkable Gelatin methacrylate (GelMA) nanofibers with the purpose of developing a highly biocompatible biomaterial capable of eradicating endodontic infection and modulating inflammation. Stable GelMA/AV nanofibers with optimal properties were obtained at the ratio of (70:30) by electrospinning. In addition to the pronounced antibacterial effect against Enterococcus faecalis, the GelMA/AV (70:30) nanofibers also exhibited a sustained antibacterial activity over 14 days and significant biofilm reduction with minimal cytotoxicity, as well as anti-inflammatory properties and immunomodulatory effects favoring healing. Our results indicate that the novel GelMA/AV (70:30) nanofibers hold great potential as a biomaterial strategy for endodontic infection eradication and enhanced healing.

Calcium Trimetaphosphate-Loaded Electrospun Poly(Ester Urea) Nanofibers for Periodontal Tissue Engineering

The objective of this research was to create and appraise biodegradable polymer-based nanofibers containing distinct concentrations of calcium trimetaphosphate (Ca-TMP) for periodontal tissue engineering. Poly(ester urea) (PEU) (5% w/v) solutions containing Ca-TMP (15%, 30%, 45% w/w) were electrospun into fibrous scaffolds. The fibers were evaluated using SEM, EDS, TGA, FTIR, XRD, and mechanical tests. Degradation rate, swelling ratio, and calcium release were also evaluated. Cell/Ca-TMP and cell/scaffold interaction were assessed using stem cells from human exfoliated deciduous teeth (SHEDs) for cell viability, adhesion, and alkaline phosphatase (ALP) activity. Analysis of variance (ANOVA) and post-hoc tests were used (α = 0.05). The PEU and PEU/Ca-TMP-based membranes presented fiber diameters at 469 nm and 414-672 nm, respectively. Chemical characterization attested to the Ca-TMP incorporation into the fibers. Adding Ca-TMP led to higher degradation stability and lower dimensional variation than the pure PEU fibers; however, similar mechanical characteristics were observed. Minimal calcium was released after 21 days of incubation in a lipase-enriched solution. Ca-TMP extracts enhanced cell viability and ALP activity, although no differences were found between the scaffold groups. Overall, Ca-TMP was effectively incorporated into the PEU fibers without compromising the morphological properties but did not promote significant cell function.

The role of selenium and zinc oxide nanoparticles on mitigating side effects of obesity in rats

Obesity and related diseases represent greatest threats to human health. Nanoparticles (NPs) serve to reduce toxicity; reinforce bioactivity and improve targeting. This study was intended to investigate the antiobesity and antioxidant activities of selenium and zinc oxide nanoparticles.

METHODS

Twenty four adult male rats were divided into four groups, group1 control rats fed normal diet and the other three groups were fed high fat diet (HFD) for 10 weeks to induce obesity and injected intraperitoneally with saline, SeNPs (30μg/kg b.wt) and ZnONPs (5mg/kg b.wt) respectively on the last two weeks of feeding (9th and 10th).

RESULTS

HFD increased body weight, oxidative stress as indicated by elevated lipid peroxidation and decreased glutathione and catalase levels, increased significantly serum lipid fractions, leptin, liver enzymes, creatinine and uric acid. While causing a substantial decrease in HDL-C and thyroid hormone T4 levels. The results confirmed that treatment with SeNPs and ZnONPs significantly reduced body weight, MDA and improved liver and kidney functions, ameliorated serum lipid fractions level and significantly increased glutathione, catalase, HDL-C and thyroid hormone.

CONCLUSION

SeNPs and ZnONPs significantly mitigate hyperlipidemia and oxidative stress. So, they might be potential candidate for obesity amelioration.

Food handlers: an important reservoir of protozoans and helminth parasites of public health importance

Food handlers plays a primary role in the transmission of pathogenically important protozoans and helminth parasites. This study was aimed to evaluate the prevalence of intestinal pathogenic protozoans and helminth parasites among food handlers in and around University of Malakand, Lower Dir, Pakistan. Stool samples were collected from 642 food handlers (all of male) in a cross-sectional study from January to November, 2017. Wet Mount Techniques and concentration methods by using salt and formol-ether solutions. Three hundred and eighty four cases (59.8%) were found infected with one more parasites. Most of the individuals were found infected with helminth (47.6%) as compared to intestinal protozoans (0.93%). Seventy two cases (11.2%) of the cases presented mixed infection with both intestinal protozoan and helminth parasites. The order of prevalence for intestinal helminth was Ancylostoma duodenale (n = 258, 40.1%), followed by Taeniasa ginata (n=96, 14.9%) Ascaris lumbricoides (n = 54, 8.40%) and Trichuris trichura (n=30, 4.60%). For intestinal protozoa, Entamoeba histolytica/dispar (n = 36, 5.64%) was the only protozoan detected. Mono-parasitism was higher than poly-parasitism. Family size income and education level were the factors significantly (P<0.05) associated in the parasites prevalence. Current research showed that IPIs are primarily the foodborne pathogens still an important public health problem in Pakistan. Effective control programs on parasitic diseases transfer and their associated factors are recommended.

Evaluation of vegetables grown in dry mountainous regions for soil transmitted helminths contamination

Infection caused by geo-helminth parasites are called geohelminthiasis are one of the global health problems. Vegetables eaten raw is the principal source of transmission of geo-helminth parasites. Pakistani people believe that eating raw vegetables are a significant source to get important vitamins and minerals. Based on the high incidence of pathogenic parasites and cultivating different vegetable types in the study areas, we conducted this study to evaluate the geo-helminth contamination of raw vegetables in northwest Khyber Pakhtunkhwa, Pakistan. This is a descriptive study comprised, 1942 samples of 25 various types of vegetables. The samples were examined in physiological saline solution using sedimentation and centrifugation methods. The findings were analyzed by Graph-Pad version 5. P value less than 0.05 (95% CI) was considered significant. Results showed that 16.5% (n=322) of all vegetables were contaminated with one or more type of geo-helminth parasites. Garlic was the highest (35%) and cauliflower the lowest (4%) contaminated samples respectively. Ascaris lumbricoides was the most common geo-helminth found followed by hook worm species while Trichuris trichura was the least in all the vegetable samples. Leafy vegetables were highly contaminated 25.3% than vegetables with root parts 21.2% and fruity 9.09%. More than half of the contaminated vegetables were contaminated with single species of geo-helminth (P<0.05) while less than half with multiple types of geo-helminth contamination. Ninety two vegetables samples were contaminated with 2 species of parasites (P<0.05) and 45 with 3 (P>0.05) species of geo-helminth parasites. Education level of vendors and means of display were not significantly associated while types of vegetable used were significantly associated with the prevalence of parasites. The findings of this study provide evidence that consumption of raw vegetable has a high risk of acquiring geo-helminth infections. The authors believe that preventing the human to enter to the vegetable farmland for defecation, avoiding the irrigation of agricultural fields via night soil, and educating the people on proper washing and cooking of vegetables may be useful in reducing parasitic infections.

Evaluation of sulfadimidine, amprolium and triquen to treat coccidiosis in wild pigeons

Coccidiosis remains one of the major problems in poultry all over the world. Very limited data on anticoccidial drugs in wild pigeons is available. The current study was aimed to understand the comparative efficacy of sulfadimidine, amprolium and triquen in wild pigeons of Dir district, Pakistan suffering from coccidiosis. The faecal matter of wild pigeons were purchased from the local market for coccidian infection. Results revealed that 88.8% (16/18) were found infected with Eimeria spp. Three positive groups were treated with sulfadimidine (0.2mg/L), amprolium (25mg/L) and triquen. Sulfadimidine was most effective (45%) followed by amprolium (44.6%) while triquen (24.0%) showed less effectiveness against coccidiosis in pigeons. Number of oocysts were 79, 81 and 80 before treatment and 60, 44 and 44 after treatment with sulfadimidine, amprolium and triquen respectively. This study showed that sulphadimidine, amprolium and triquen could not significantly reduce the coccidiosis in pigeons. Further studies are required to clear the mechanism of anti-coccidial drugs in wild pigeons.

Free radical scavengers in susceptible/resistant Biomphalaria alexandrina snails before and after infection

The activities of catalase (Cat), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), glutathione transferase (GST), glucose-6-phosphate dehydrogenase (G6PD) and glyceraldehyde3-phosphate dehydrogenase (G3PD) were studied in tissue and hemolymph of susceptible (S) (EgBS(2)) and resistant (R) (EgBR(2)) Biomphalaria alexandrina snails. The results showed that CAT and GST were higher in the hemolymph of snails susceptible to Schistosoma mansoni than in that of snails resistant to infestation, while SOD and G3PD were lower in the susceptible snails. The role of these enzymes as free radical scavengers was traced 1 and 24 h after infection of the two snail lines with S. mansoni. Moreover, the activities of SOD and G3PD were also measured 2 and 4 weeks post infection. The results revealed that the overall enzymatic activities were higher in susceptible than in resistant snail tissues. After 1 h of infection, all enzymes were increased in R and S snails except GST and G6PD which decreased in S snails. After 24 h of infection, GST increased in S snails and G3PD decreased in both S and R snails while other enzymes reached normal levels.

Factors affecting the fate of prolonged forgotten 'J' stents

PURPOSE

To compare the effects of age and presence or absence of renal impairment at the time of 'J' stent insertion on the subsequent fate of prolonged forgotten stents.

PATIENTS AND METHODS

A patient was described as having a prolonged forgotten 'J' stent, if the patient's 'J' stent was removed more than 12 months after it had been inserted. We compared the effect of age at insertion and presence or absence of renal impairment on the complications encountered in such patients. We describe briefly the management of the complications. We defined a patient as having moderate renal impairment if the patient has serum creatinine >200 < 500 micromol/l and is not on dialysis.

RESULTS

We treated 17 patients with forgotten 'J' stents between 1994 and 2000. Fifteen were adults, mean age 25 (range 18-72) years, and 2 were children 9 and 10 years respectively at the time the stents were inserted. The mean duration of stent retention was 24.30 (range 12-60) months. In 12 patients the stents were forgotten for between 12 and 18 months. In these, the stents had varying degrees of calcification but were easily removed intact endoscopically in 11 out of 12 cases. One 10-year-old boy in this group required open surgical removal of the stent. In one 35-year-old patient, the stent was forgotten for 36 months. It had fractured spontaneously in 7 places and required endoscopic and open removal of stent fragments. In 2 cases, a growing 9-year-old boy, and a 30-year-old man the stents were forgotten for 46 and 48 months respectively. After 46 months of retaining the stent, the stent spontaneously fractured in 11 places in the growing child, while in the adult it became heavily calcified and fractured during attempts to remove it endoscopically. Two adult patients with moderate renal failure at the time of stent insertion retained the stents for 40 and 60 months respectively. One of these 2 stents had a minor calcification at the tip of the stent in the renal pelvis. Both stents were removed intact endoscopically and showed no sign of fracture or calcification.

CONCLUSION

In a growing child a prolonged forgotten 'J' stent is very likely to undergo spontaneous fracture due to the stress exerted on it as a result of cranio-caudal growth of the child. In adults, prolonged forgotten stents become calcified, brittle and lose tensile strength after more than one year of placement and may fracture either spontaneously or during attempts to remove them endoscopically. In patients producing hypotonic urine such as patients with moderate renal failure, a prolonged forgotten stent may remain little affected by the passage of time.

Silent obstruction after extracorporeal piezoelectric lithotripsy

Extracorporeal piezoelectric lithotripsy (EPL) is frequently used to treat renal calculi. We are presenting a case that developed silent ureteric obstruction following three sessions of EPL of 4,000 shocks each. The obstruction was silent and asymptomatic, and was detected 6 weeks later on a routine follow-up renogram. The obstruction was due to an impacted stone fragment in the lower ureter. After release of the obstruction, the kidney function did not return to pre-therapy levels due to irreversible damage. This case demonstrates the importance of doing renograms before and within a few days after shock therapy for renal stones.

Evaluation of renal functional changes after extracorporeal piezoelectric lithotripsy (EPL) by radionuclide studies

Extracorporeal piezoelectric lithotripsy (EPL) has been recently introduced as a non-invasive method for treatment of renal and gall bladder stones. Thirty seven patients treated with EPL for renal calculi were the subjects of radionuclide renal studies. The aim was to evaluate the effects of EPL as a new technology by radionuclide renography. 99Tcm-DTPA and 99Tcm-DMSA studies were performed pre-EPL and one day and one week post-EPL. Various parameters of the sequential radionuclide studies were evaluated. One day post-EPL, changes in parenchymal transit time index, relative uptake function, glomerular filtration rate, time-activity curves and kidney dimensions were observed. At one week post-EPL, different parameters returned to baseline status in the majority of cases. The study indicates that EPL has a variety of effects on the kidney that could be demonstrated and followed by sequential radionuclide renal studies. Furthermore the study suggests spacing of EPL sessions by approximately one week.

Echinococcosis in Egypt: IV. Serology on patients with chest problems

Patients complaining of chest disorders were clinically and serologically examined for evidence of echinococcal infection. Serologically, the patients were screened by the indirect haemagglutination test and reactors were confirmed by the bentonite flocculation and/or latex-agglutination tests. Of 755 patients 6.2 percent had echinococcal antibodies in their sera. Of 393 patients given a chest radiography one patient (0.25%) had distinct pulmonary hydatid cysts. The bentonite flocculation technique picked more of the positives (91.5%) than did the latex-agglutination (14.9%) technique. Females were more exposed to echinococcal infection (8.4%) than males (2.3%). Among positives, 71-75 per cent were below thirty years old. Prevalence of infection was higher among individuals having direct contact with dogs (4.6%) than among individuals with no direct contact with dogs (3.2%). Evidently cross-reactions between the echinococcal antigen and antibodies of some bacterial and parasitic infections including schistosomiasis interfere with the haemagglutination test results.