Correlation between Ca Release and Osteoconduction by 3D-Printed Hydroxyapatite-Based Templates.

The application of hydroxyapatite (HA)-based templates is quite often seen in bone tissue engineering since that HA is an osteoconductive bioceramic material, which mimics the inorganic component of mineralized tissues. However, the reported osteoconductivity varies in vitro and in vivo, and the levels of calcium (Ca) release most favorable to osteoconduction have yet to be determined. In this study, HA-based templates were fabricated by melt-extrusion 3D-printing and characterized in order to determine a possible correlation between Ca release and osteoconduction. The HA-based templates were blended with poly(lactide-co-trimethylene carbonate) (PLATMC) at three different HA ratios: 10, 30, and 50%. The printability and physical properties of the HA templates were compared with those of pristine PLATMC. In vitro, osteoconductivity was assessed using seeded human bone marrow-derived mesenchymal stem cells. A mild rate of Ca release was observed for HA10 templates, which exhibited higher mineralized extracellular matrix (ECM) secretion than PLATMC at 14 and 21 days. In contrast, the high rate of Ca release exhibited by HA30 and HA50 templates was associated with reduced osteoconduction and impeded mineralized ECM secretion in vitro. Similar results were observed in vivo. In the calvarial defect model in rabbit, PLATMC and HA10 templates exhibited the highest amount of new bone formation, with obvious contact osteogenesis on their surfaces. In contrast, HA30 and HA50 exhibited distant osteogenesis and reduced amounts of new bone ingrowth. It is concluded that HA-based templates are osteoconductive only at low rates of Ca release.

Perception of consanguineous marriage among the qatari population.

Background: Hereditary blood diseases are widespread among the Arab population due to the high rates of consanguineous marriages; research regarding the perception of consanguineous marriage in some countries, such as Qatar, is extremely scarce. Therefore, this study aimed to investigate the prevalence of consanguineous marriage and assess the perception of consanguineous marriage among the Qatari population. Methods: A cross-sectional study used a self-administered questionnaire among 395 Qatari adults aged 18-35 who attended primary healthcare institutions in Qatar. A convenience sampling technique was used to select the study participants. An independent t-test was used to compare the significance of the mean between the two groups with positive and negative perceptions of consanguineous marriage. Categorical data were analyzed for association using the chi-square or Fisher's exact test. Finally, a multiple logistic regression analysis was conducted to determine the significant predictors of the positive perception of consanguineous marriage. A significant level was set at p < 0.05. Results: Approximately 45% of the participants had a positive perception toward consanguineous marriage, and the most common reason stated by those participants was "habit and traditions." The prevalence of consanguineous marriage among married couples was 62.6%, and among those with consanguineous marriage, most were married to first cousins (81.7%). Moreover, compared to the participants with negative perceptions of consanguineous marriage, those with positive ones were significantly older, married, with lower educational levels and higher monthly income levels, did not hear about glucose-6-phosphate dehydrogenase (G6PD) deficiency, did not know what kinds of diseases are being screened in the premarital test, and were married to a relative. Conclusion: The prevalence of consanguineous marriage is high among the Qatari population, and this requires an immediate need for community-based campaigns to raise public awareness about the problem and its potential impact.

Unique osteogenic profile of bone marrow stem cells stimulated in perfusion bioreactor is Rho-ROCK-mediated contractility dependent.

The fate determination of bone marrow mesenchymal stem/stromal cells (BMSC) is tightly regulated by mechanical cues, including fluid shear stress. Knowledge of mechanobiology in 2D culture has allowed researchers in bone tissue engineering to develop 3D dynamic culture systems with the potential for clinical translation in which the fate and growth of BMSC are mechanically controlled. However, due to the complexity of 3D dynamic cell culture compared to the 2D counterpart, the mechanisms of cell regulation in the dynamic environment remain relatively undescribed. In the present study, we analyzed the cytoskeletal modulation and osteogenic profiles of BMSC under fluid stimuli in a 3D culture condition using a perfusion bioreactor. BMSC subjected to fluid shear stress (mean 1.56 mPa) showed increased actomyosin contractility, accompanied by the upregulation of mechanoreceptors, focal adhesions, and Rho GTPase-mediated signaling molecules. Osteogenic gene expression profiling revealed that fluid shear stress promoted the expression of osteogenic markers differently from chemically induced osteogenesis. Osteogenic marker mRNA expression, type 1 collagen formation, ALP activity, and mineralization were promoted in the dynamic condition, even in the absence of chemical supplementation. The inhibition of cell contractility under flow by Rhosin chloride, Y27632, MLCK inhibitor peptide-18, or Blebbistatin revealed that actomyosin contractility was required for maintaining the proliferative status and mechanically induced osteogenic differentiation in the dynamic culture. The study highlights the cytoskeletal response and unique osteogenic profile of BMSC in this type of dynamic cell culture, stepping toward the clinical translation of mechanically stimulated BMCS for bone regeneration.

Hybrid material based on hyaluronan hydrogels and poly(l-lactide-co-1,3-trimethylene carbonate) scaffolds toward a cell-instructive microenvironment with long-term in vivo degradability.

Degradable polyester-based scaffolds are ideal for tissue engineering applications where long-term structural integrity and mechanical support are a requisite. However, their hydrophobic and unfunctionalized surfaces restrain their tissue-mimetic quality. Instead, hyaluronan (HA) hydrogels are able to act as cell-instructive materials with the ability to recapitulate native tissue, although HA is rapidly metabolized in vivo. Taking advantage of these distinctly diverse material properties, a degradable and concurrent hybrid hydrogel material was developed that combines the short-term tissue-relevant properties of bio-orthogonal crosslinked HA with the long-term structural and mechanical support of poly(l-lactide-co-trimethylene carbonate) (PLATMC) scaffolds. This method rendered the formulation of transparent, minimally swelling hydrogel compartments with a desirable cell-instructive "local" elastic modulus within the scaffold matrix without impeding key material properties of PLATMC. Long-term degradability over 180 days in vivo was realized by the integral PLATMC scaffold architecture obtained through either extrusion-based 3D printing or salt-particulate leaching. Intrinsic diffusion capacity within the hydrogel elicited unaffected degradation kinetics of PLATMC in vivo, despite its autocatalytic bulk degradation characteristics displayed when 3D-printed. The effect of the processing method on the material properties of PLATMC markedly extends to its in vivo degradation characteristics, and essential uniform degradation behavior can be advanced using salt-particulate leaching. Regardless of the scaffold fabrication method, the polymer exhibited a soft and flexible nature throughout the degradation period, governed by the rubbery state of the polymer. Our results demonstrate that the physicochemical properties of the hybrid hydrogel scaffold endow it with the potential to act as a cell instructive microenvironment while not affecting key material properties of PLATMC postprocessing. Importantly, the HA hydrogel does not adversely impact the degradation behavior of PLATMC, a vital aspect in the fabrication of tissue engineering constructs. The results presented herein open new avenues for the adoption of concurrent and well-defined tissue-relevant materials exhibiting the potential to recreate microenvironments for cell encapsulation and drug delivery in vivo while providing essential structural integrity and long-term degradability.

Enhancing Tuberculosis Case-Finding: A Case of Quality Improvement Initiative in Tanzania.

BACKGROUND: Tanzania is 1 of the 30 high TB burden countries and 1 of the 13 countries in which 75% of people with TB are unaccounted for and that is prioritized for the Global Fund Catalytic investment and Strategic Initiative support. Tanzania decided to strengthen its National TB Programme to find these people with TB who are unaccounted for by identifying evidence-driven innovations to deliver high-quality services and to improve the efficiency of TB case-finding. A quality improvement (QI) initiative was implemented by the National Tuberculosis and Leprosy Programme to enhance TB case-finding. The initiative involved identifying gaps in the quality of services, introducing new tools, improving the work capacity of health care workers through training and mentorship sessions, strengthening laboratory and referral services, and implementing mandatory TB screening of all patients attending health facilities. We aimed to assess the effectiveness of QI initiative to enhance TB case-findings at the health facility level. METHOD: A cross-sectional design, and intervention and control facilities randomly selected for an evaluation of the QI initiative were used. Twenty facilities from the Dodoma region across all health care system levels (dispensaries, health centres, and hospitals) were involved in this evaluation. The facilities were randomly divided into either the intervention or control groups at a 1:1 ratio (10 intervention and 10 control facilities). Data routinely collected from program registers from January 2016 to June 2017 were used. RESULT: The evaluation registered a 52% increase in TB case notification in Q1 of 2017 compared with in Q1 of 2016 and, similarly, a 52% increase in Q2 of 2017 compared with in Q2 of 2016, with 9 out of 10 intervention sites reporting increases in their quarterly TB case notifications. There were no positive changes in the 'control facilities' where routine services were provided, with half of the facilities showing a decrease in TB case notification from baseline. CONCLUSION: This QI initiative has the potential to support a long-term comprehensive approach to ending TB and to improve the quality of the foundations of the health care system. This initiative sets a reliable pace for health facilities to efficiently respond to and manage TB case-finding interventions put into action. Tanzania's experience with implementing QI interventions could serve as a model for improving TB case notifications in other settings.

Optimization and Validation of a Custom-Designed Perfusion Bioreactor for Bone Tissue Engineering: Flow Assessment and Optimal Culture Environmental Conditions.

Various perfusion bioreactor systems have been designed to improve cell culture with three-dimensional porous scaffolds, and there is some evidence that fluid force improves the osteogenic commitment of the progenitors. However, because of the unique design concept and operational configuration of each study, the experimental setups of perfusion bioreactor systems are not always compatible with other systems. To reconcile results from different systems, the thorough optimization and validation of experimental configuration are required in each system. In this study, optimal experimental conditions for a perfusion bioreactor were explored in three steps. First, an in silico modeling was performed using a scaffold geometry obtained by microCT and an expedient geometry parameterized with porosity and permeability to assess the accuracy of calculated fluid shear stress and computational time. Then, environmental factors for cell culture were optimized, including the volume of the medium, bubble suppression, and medium evaporation. Further, by combining the findings, it was possible to determine the optimal flow rate at which cell growth was supported while osteogenic differentiation was triggered. Here, we demonstrated that fluid shear stress up to 15 mPa was sufficient to induce osteogenesis, but cell growth was severely impacted by the volume of perfused medium, the presence of air bubbles, and medium evaporation, all of which are common concerns in perfusion bioreactor systems. This study emphasizes the necessity of optimization of experimental variables, which may often be underreported or overlooked, and indicates steps which can be taken to address issues common to perfusion bioreactors for bone tissue engineering.

Efficacy of treating segmental bone defects through endochondral ossification: 3D printed designs and bone metabolic activities.

Three-dimensional printing (3D printing) is a promising technique for producing scaffolds for bone tissue engineering applications. Porous scaffolds can be printed directly, and the design, shape and porosity can be controlled. 3D synthetic biodegradable polymeric scaffolds intended for in situ bone regeneration must meet stringent criteria, primarily appropriate mechanical properties, good 3D design, adequate biocompatibility and the ability to enhance bone formation. In this study, healing of critical-sized (5 â€‹mm) femur defects of rats was enhanced by implanting two different designs of 3D printed poly(l-lactide-co-ε-caprolactone) (poly(LA-co-CL)) scaffolds seeded with rat bone marrow mesenchymal stem cells (rBMSC), which had been pre-differentiated in vitro into cartilage-forming chondrocytes. Depending on the design, the scaffolds had an interconnected porous structure of 300-500 â€‹µm and porosity of 50-65%. According to a computational simulation, the internal force distribution was consistent with scaffold designs and comparable between the two designs. Moreover, the defects treated with 3D-printed scaffolds seeded with chondrocyte-like cells exhibited significantly increased bone formation up to 15 weeks compared with empty defects. In all experimental animals, bone metabolic activity was monitored by positron emission tomography 1, 3, 5, 7, 11 and 14 weeks after surgery. This demonstrated a time-dependent relationship between scaffold design and metabolic activity. This confirmed that successful regeneration was highly reproducible. The in vitro and in vivo data indicated that the experimental setups had promising outcomes and could facilitate new bone formation through endochondral ossification.

Surface activation with oxygen plasma promotes osteogenesis with enhanced extracellular matrix formation in three-dimensional microporous scaffolds.

Various types of synthetic polyesters have been developed as biomaterials for tissue engineering. These materials commonly possess biodegradability, biocompatibility, and formability, which are preferable properties for bone regeneration. The major challenge of using synthetic polyesters is the result of low cell affinity due to their hydrophobic nature, which hinders efficient cell seeding and active cell dynamics. To improve wettability, plasma treatment is widely used in industry. Here, we performed surface activation with oxygen plasma to hydrophobic copolymers, poly(l-lactide-co-trimethylene carbonate), which were shaped in 2D films and 3D microporous scaffolds, and then we evaluated the resulting surface properties and the cellular responses of rat bone marrow stem cells (rBMSC) to the material. Using scanning electron microscopy and Fourier-transform infrared spectroscopy, we demonstrated that short-term plasma treatment increased nanotopographical surface roughness and wettability with minimal change in surface chemistry. On treated surfaces, initial cell adhesion and elongation were significantly promoted, and seeding efficiency was improved. In an osteoinductive environment, rBMSC on plasma-treated scaffolds exhibited accelerated osteogenic differentiation with osteogenic markers including RUNX2, osterix, bone sialoprotein, and osteocalcin upregulated, and a greater amount of collagen matrix and mineral deposition were found. This study shows the utility of plasma surface activation for polymeric scaffolds in bone tissue engineering.

Comparison of bone regenerative capacity of donor-matched human adipose-derived and bone marrow mesenchymal stem cells.

Adipose-derived stem cells (ASC) have been used as an alternative to bone marrow mesenchymal stem cells (BMSC) for bone tissue engineering. However, the efficacy of ASC in bone regeneration in comparison with BMSC remains debatable, since inconsistent results have been reported. Comparing ASC with BMSC obtained from different individuals might contribute to this inconsistency in results. Therefore, this study aimed to compare the bone regenerative capacity of donor-matched human ASC and BMSC seeded onto poly(L-lactide-co-ε-caprolactone) scaffolds using calvarial bone defects in nude rats. First, donor-matched ASC and BMSC were seeded onto the co-polymer scaffolds to evaluate their in vitro osteogenic differentiation. Seeded scaffolds and scaffolds without cells (control) were then implanted in calvarial defects in nude rats. The expression of osteogenesis-related genes was examined after 4 weeks. Cellular activity was investigated after 4 and 12 weeks. Bone formation was evaluated radiographically and histologically after 4, 12, and 24 weeks. In vitro, ASC and BMSC demonstrated mineralization. However, BMSC showed higher alkaline phosphatase activity than ASC. In vivo, human osteogenesis-related genes Runx2 and collagen type I were expressed in defects with scaffold/cells. Defects with scaffold/BMSC had higher cellular activity than defects with scaffold/ASC. Moreover, bone formation in defects with scaffold/BMSC was greater than in defects with scaffold/ASC, especially at the early time-point. These results suggest that although ASC have the potential to regenerate bone, the rate of bone regeneration with ASC may be slower than with BMSC. Accordingly, BMSC are more suitable for bone regenerative applications.

Ramadan Fasting in a Patient with Chronic Myeloid Leukemia Receiving Nilotinib as Upfront.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm classically described as triphasic disease: chronic, accelerated, and blast crisis. There are many unmet needs and unanswered questions about CML. Intermittent fasting in patients with CML on tyrosine kinase inhibitors is among these unmet needs. Here we report the effect of intermittent fasting on response to nilotinib as upfront in a 49-year-old female Muslim who fasted during Ramadan and took her medication once instead of twice daily and remained in major molecular response.

Yield of household contact investigation of patients with pulmonary tuberculosis in southern Ethiopia.

BACKGROUND: Household Contacts (HHCs) of patients with pulmonary tuberculosis (PTB) have a higher risk of developing TB. Contact investigation is recommended to reach this group and identify undiagnosed cases. In this study, we have determined the yield of contact investigation among HHCs of patients with smear-positive PTB, and estimated TB burden. METHODS: We conducted retrospective record review for the occurrence of TB among HHCs of Index PTB+ cases treated between November 2010 and April 2013 in 12 public health facilities in Boricha district. HHCs were followed up monthly and revisited between March and June 2015. Information on additional TB cases diagnosed and treated among HHCs were documented. HHCs who were diagnosed as having TB after the index cases were diagnosed and treated were considered as 'incident cases'. Presumptive TB case was defined as those having cough for ≥2 weeks or enlarged lymph node. Diagnosis of TB among HHCs were made using smear-microscopy and/or X-rays, and clinically for Extra-pulmonary TB (EPTB). RESULTS: One thousand five hundred and seventeenth HHCs of 344 index cases were visited and screened for TB and followed up for a median of 37 months. 77 (5.1% - 72 with PTB and 5 with EPTB) HHCs developed TB during 4713 person-years of follow-up with an estimated incidence of 1634 (95% CI: 1370-2043) per 100,000 person-years follow-up which is much higher than the estimated TB incidence for the general population in Ethiopia of 210/100,000. Half (41/77) of incident TB cases were diagnosed within the first year of diagnosis of the index cases and 88% (68/77) were adults (Hazard Ratio: 4.03; 95% CI: 2.00-8.12). CONCLUSION: HHCs of index PTB+ cases have high risk of developing active TB. Long term follow-up of HHCs could help improve TB case finding depending on country contexts. Further studies on effectiveness and feasibility of the approach and integration in routine settings are needed.

Factors contributing to drug-resistant tuberculosis treatment outcome in five countries in the Eastern Europe and Central Asia region.

Drug-resistant tuberculosis (DR-TB) is a global challenge and a major contributor of death from anti-microbial resistance. With the main aim to determine factors contributing to treatment outcomes observed among DR-TB patients in the countries in Eastern Europe and Central Asia (EECA), a multi-method study was conducted in: Azerbaijan, Belarus, Romania, Tajikistan and Ukraine. Both quantitative and qualitative methodologies were used for data collection and analysis. The quantitative approaches included a desk review of documents related to the DR-TB responses and an analysis of clinical records of DR-TB patients in selected health facilities of the five countries. Qualitative methods included in-depth interviews with national TB programme (NTP) managers, other healthcare providers and non-governmental organizations (NGOs) workers, as well as interviews and Focus Group Discussions (FGDs) with DR-TB patients. The desk review of 38 reports identified as the main challenges to address DR-TB financial and/or management issues and adverse events of the medicines. The most common recommendations related to treatment outcome focussed on general programme management, treatment regimen composition, clinical management and social support for the patients. In all the five countries the NTPs still have a vertical structure. Some integration into the primary health care system (PHC) already exists but further involvement of PHC facilities is feasible and recommended. Interviews with stakeholders indicated that alcoholism and homelessness and a lack of appropriate response to these issues remain as major challenges for a sub-set of patients. Civil society groups, NGOs and communities are substantially engaged in providing different services to DR-TB patients, especially in Ukraine, Romania and Tajikistan. Data from clinical records of 212 patients revealed that independent risk factors for unfavourable treatment outcome (death, loss to follow-up, failure) were culture-positivity at two months of treatment, history of treatment with second-line drugs and homelessness. More powerful, less toxic and shorter oral treatment regimens as well as comprehensive patient support are needed to improve treatment outcome of patients with DR-TB.

Printability and Critical Insight into Polymer Properties during Direct-Extrusion Based 3D Printing of Medical Grade Polylactide and Copolyesters.

Various 3D printing techniques currently use degradable polymers such as aliphatic polyesters to create well-defined scaffolds. Even though degradable polymers are influenced by the printing process, and this subsequently affects the mechanical properties and degradation profile, degradation of the polymer during the process is not often considered. Degradable scaffolds are today printed and cell-material interactions evaluated without considering the fact that the polymer change while printing the scaffold. Our methodology herein was to vary the printing parameters such as temperature, pressure, and speed to define the relationship between printability, polymer microstructure, composition, degradation profile during the process, and rheological behavior. We used high molecular weight medical-grade (co)polymers, poly(l-lactide-co-ε-caprolactone) (PCLA), poly(l-lactide-co-glycolide) (PLGA), and poly(d,l-lactide-co-glycolide) (PDLGA), with l-lactide content ranging from 25 to 100 mol %, for printing in an extrusion-based printer (3D Bioplotter). Optical microscopy confirmed that the polymers were printable at high resolution and good speed, until a certain degree of degradation. The results show also that printability can not be claimed just by optimizing printing parameters and highlight the importance of a careful analysis of how the polymer's structure and properties vary during printing. The polymers thermally decomposed from the first processing minute and caused a decrease in the average block length of the lactide blocks in the copolymers and generated lower crystallinity. Poly(l-lactide) (PLLA) and PCLA are printable at a higher molecular weight, less degradation before printing was possible, compared to PLGA and PDLGA, a result explained by the higher complex viscosity and more elastic polymeric melt of the copolymer containing glycolide (GA) and lactide (LA). In more detail, copolymers comprised of LA and ε-caprolactone (CL) formed lower molecular weight compounds over the course of printing, while the PLGA copolymer was more susceptible to intermolecular transesterification reactions, which do not affect the overall molecular weight, but cause changes in the copolymer microstructure. This results in a longer printing time for PLGA than PLLA and PCLA.

Adenoviral mediated mono delivery of BMP2 is superior to the combined delivery of BMP2 and VEGFA in bone regeneration in a critical-sized rat calvarial bone defect.

Apart from osteogenesis, neovascularization of the defect area is an important determinant for successful bone healing. Accordingly, several studies have employed the combined delivery of VEGFA and BMP2 for bone regeneration. Nevertheless, the outcomes of these studies are highly variable. The aim of our study was to compare the effectiveness of adenoviral mediated delivery of BMP2 alone and in combination with VEGFA in rat bone marrow stromal cells (rBMSC) seeded on a poly(LLA-co-CL) scaffold in angiogenesis and osteogenesis using a critical-sized rat calvarial defect model. Both mono delivery of BMP2 and the combined delivery of a lower ratio of VEGFA and BMP2 (1:4) led to up-regulation of osteogenic genes (Alpl and Runx2) and increased calcium deposition in vitro, compared with the GFP control. Micro computed tomography (microCT) analysis of the rat calvarial defect at 8 weeks showed that the mono delivery of BMP2 (43.37 ±â€¯3.55% defect closure) was the most effective in healing the bone defect, followed by the combined delivery of BMP2 and VEGFA (27.86 ±â€¯2.89%) and other controls. Histological and molecular analyses supported the microCT findings. Analysis of the angiogenesis, however, showed that both mono delivery of BMP2 and combined delivery of BMP2 and VEGFA had similar angiogenic effect in the calvarial defects. Examination of the key genes related to host response against the adenoviral vectors showed that the current model system was not associated with adverse immune response. Overall, the results show that the mono delivery of BMP2 was superior to the combined delivery of BMP2 and VEGFA in healing the critical-sized rat calvarial bone defect. These findings underscore the importance of appropriate growth factor combination for the successful outcome in bone regeneration.

3D and Porous RGDC-Functionalized Polyester-Based Scaffolds as a Niche to Induce Osteogenic Differentiation of Human Bone Marrow Stem Cells.

Polyester-based scaffolds covalently functionalized with arginine-glycine-aspartic acid-cysteine (RGDC) peptide sequences support the proliferation and osteogenic differentiation of stem cells. The aim is to create an optimized 3D niche to sustain human bone marrow stem cell (hBMSC) viability and osteogenic commitment, without reliance on differentiation media. Scaffolds consisting of poly(lactide-co-trimethylene carbonate), poly(LA-co-TMC), and functionalized poly(lactide) copolymers with pendant thiol groups are prepared by salt-leaching technique. The availability of functional groups on scaffold surfaces allows for an easy and straightforward method to covalently attach RGDC peptide motifs without affecting the polymerization degree. The strategy enables the chemical binding of bioactive motifs on the surfaces of 3D scaffolds and avoids conventional methods that require harsh conditions. Gene and protein levels and mineral deposition indicate the osteogenic commitment of hBMSC cultured on the RGDC functionalized surfaces. The osteogenic commitment of hBMSC is enhanced on functionalized surfaces compared with nonfunctionalized surfaces and without supplementing media with osteogenic factors. Poly(LA-co-TMC) scaffolds have potential as scaffolds for osteoblast culture and bone grafts. Furthermore, these results contribute to the development of biomimetic materials and allow a deeper comprehension of the importance of RGD peptides on stem cell transition toward osteoblastic lineage.

Evaluation of Apical Dimension, Canal Taper and Maintenance of Root Canal Morphology Using XP-endo Shaper.

AIM: To evaluate the shaping ability of the XP-endo shaper file system in maxillary molars, representing root canals with variation in morphology. MATERIALS AND METHODS: Twenty maxillary molars were instrumented according to recommended protocols. Pre- and postoperative microcomputed tomography (CT) scans were performed and the root canals classified according to canal type and curvature. The volume change, number of strokes needed to prepare the canals and the size of the 0.04-tapered gutta-percha cone that was adapted in the canal were recorded. RESULTS: XP-endo shaper created a significant change in volume after instrumentation in all the canals, with the biggest change found in the DB canals, followed by the MB1 and the P canals, both at full length and in the apical 4 mm. The number of strokes needed to achieve working length and final shape did not differ between the various root canals. Although not significant, the number of strokes needed to prepare the root canal increased with severity of the curvature, but the severity of the curvature did not result in increased removal of dentin in the apical 4 mm. It was possible to achieve a final root canal size where a 0.04-tapered gutta-percha cone could be adapted. CONCLUSION: The XP-endo shaper was a safe and effective instrument to achieve a root canal preparation of at least size 30 and a 0.04 taper. CLINICAL SIGNIFICANCE: The clinical performance of XP-endo shaper was to some extent dependent on preoperative volume and curvature of the root canal.

Sub-national prevalence survey of tuberculosis in rural communities of Ethiopia.

BACKGROUND: Tuberculosis is a major public health problem with varying prevalence in different settings. National prevalence surveys provide evidence for planning and decision making. However, they lack the capacity to estimate subnational magnitude that affected the capacity to make selected intervention based on the prevalence. Ethiopia is among high TB burden countries with estimated prevalence of 108 per 100,000 population varying by regions. We aimed to study sub national prevalence of smear-positive TB in rural communities of southern Ethiopia. METHODS: This cross-sectional study, enrolled community members aged over 14 years who had cough of at least two weeks duration. Two sputum samples were collected and examined by using smear microscopy. RESULTS: 38,304 eligible people were enumerated (10,779 from Hadiya, 10,059 from Gurage and 17,466 from Sidama) and indentified 960 presumptive cases. 16, 14 and 14 smear-positive pulmonary TB cases were identified respectively. The point prevalence of smear-positive TB were 148 per 100,000 population (95% CI: 91-241) in Hadiya, 139 per 100,000 population (95% CI: 83-234) in Gurage and 80/100,000 population (95%CI: 48-135) in Sidama zone. Gurage zone had the highest prevalent to notified cases of seven to one. CONCLUSIONS: The prevalence of smear positive TB varies by districts and is high in rural southern Ethiopia compared to the estimated national prevalence. More TB patients remain missed and unreached, impacting negatively on health outcomes. TB case finding approaches should be revisited and innovative approaches and tools to identify missing people with TB should be scaled up.

Coating 3D Printed Polycaprolactone Scaffolds with Nanocellulose Promotes Growth and Differentiation of Mesenchymal Stem Cells.

3D printed polycaprolactone (PCL) has potential as a scaffold for bone tissue engineering, but the hydrophobic surface may hinder optimal cell responses. The surface properties can be improved by coating the scaffold with cellulose nanofibrils material (CNF), a multiscale hydrophilic biocompatible biomaterial derived from wood. In this study, human bone marrow-derived mesenchymal stem cells were cultured on tissue culture plates (TCP) and 3D printed PCL scaffolds coated with CNF. Cellular responses to the surfaces (viability, attachment, proliferation, and osteogenic differentiation) were documented. CNF significantly enhanced the hydrophilic properties of PCL scaffolds and promoted protein adsorption. Live/dead staining and lactate dehydrogenase release assays confirmed that CNF did not inhibit cellular viability. The CNF between the 3D printed PCL strands and pores acted as a hydrophilic barrier, enhancing cell seeding efficiency, and proliferation. CNF supported the formation of a well-organized actin cytoskeleton and cellular production of vinculin protein on the surfaces of TCP and PCL scaffolds. Moreover, CNF-coated surfaces enhanced not only alkaline phosphatase activity, but also collagen Type-I and mineral formation. It is concluded that CNF coating enhances cell attachment, proliferation, and osteogenic differentiation and has the potential to improve the performance of 3D printed PCL scaffolds for bone tissue engineering.

Delivery of VEGFA in bone marrow stromal cells seeded in copolymer scaffold enhances angiogenesis, but is inadequate for osteogenesis as compared with the dual delivery of VEGFA and BMP2 in a subcutaneous mouse model.

BACKGROUND: In bone tissue engineering (BTE), extensive research into vascular endothelial growth factor A (VEGFA)-mediated angiogenesis has yielded inconsistent results. The aim of this study was to investigate the influence on angio- and osteogenesis of adenoviral-mediated delivery of VEGFA alone or in combination with bone morphogenetic protein 2 (BMP2) in bone marrow stromal cells (BMSC) seeded onto a recently developed poly(LLA-co-CL) scaffold. METHODS: Human BMSC were engineered to express VEGFA alone or in combination with BMP2 and seeded onto poly(LLA-co-CL) scaffolds. Changes in angiogenic and osteogenic gene and protein levels were examined by quantitative reverse-transcription polymerase chain reaction (RT-PCR), PCR array, and alkaline phosphatase assay. An in vivo subcutaneous mouse model was used to investigate the effect on angio- and osteogenesis of VEGFA alone or in combination with BMP2, using microcomputed tomography (µCT), histology, immunohistochemistry, and immunofluorescence. RESULTS: Combined delivery of a lower ratio (1:3) of VEGFA and BMP2 (ad-BMP2 + VEGFA) led to upregulation of osteogenic and angiogenic genes in vitro at 3 and 14 days, compared with mono-delivery of VEGFA (ad-VEGFA) and other controls. In vivo, in a subcutaneous mouse model, both ad-VEGFA and ad-BMP2 + VEGFA scaffold explants exhibited increased angiogenesis at 2 weeks. Enhanced angiogenesis was largely related to the recruitment and differentiation of mouse progenitor cells to the endothelial lineage and, to a lesser extent, to endothelial differentiation of the implanted BMSC. µCT and histological analyses revealed enhanced de novo bone formation only in the ad-BMP2 + VEGFA group, corresponding at the molecular level to the upregulation of genes related to osteogenesis, such as ALPL, RUNX2, and SPP1. CONCLUSIONS: Although BMSC expressing VEGFA alone or in combination with BMP2 significantly induced angiogenesis, VEGFA alone failed to demonstrate osteogenic activity both in vitro and in vivo. These results not only call into question the use of VEGFA alone in bone regeneration, but also highlight the importance in BTE of appropriately formulated combined delivery of VEGFA and BMP2.

Health extension workers improve tuberculosis case finding and treatment outcome in Ethiopia: a large-scale implementation study.

BACKGROUND: Tuberculosis (TB) is a major cause of death in Ethiopia. One of the main barriers for TB control is the lack of access to health services. METHODS: We evaluated a diagnostic and treatment service for TB based on the health extension workers (HEW) of the Ethiopian Health Extension Programme in Sidama Zone, with 3.5 million population. We added the services to the HEW routines and evaluated their effect over 4.5 years. 1024 HEWs were trained to identify individuals with symptoms of TB, request sputum samples and prepare smears. Smears were transported to designated laboratories. Individuals with TB were offered treatment at home or the local health post. A second zone (Hadiya) with 1.2 million population was selected as control. We compared TB case notification rates (CNR) and treatment outcomes in the zones 3 years before and 4.5 years after intervention. RESULTS: HEWs identified 216 165 individuals with symptoms and 27 918 (12%) were diagnosed with TB. Smear-positive TB CNR increased from 64 (95% CI 62.5 to 65.8) to 127 (95% CI 123.8 to 131.2) and all forms of TB increased from 102 (95% CI 99.1 to 105.8) to 177 (95% CI 172.6 to 181.0) per 100 000 population in the first year of intervention. In subsequent years, the smear-positive CNR declined by 9% per year. There was no change in CNR in the control area. Treatment success increased from 76% before the intervention to 95% during the intervention. Patients lost to follow-up decreased from 21% to 3% (p<0.001). CONCLUSION: A community-based package significantly increased case finding and improved treatment outcome. Implementing this strategy could help meet the Ethiopian Sustainable Development Goal targets.