Adeno-associated virus serotype 2 capsid variants for improved liver-directed gene therapy.

BACKGROUND AND AIMS: Current liver-directed gene therapies look for adeno-associated virus (AAV) vectors with improved efficacy. With this background, capsid engineering is explored. Whereas shuffled capsid library screenings have resulted in potent liver targeting variants with one first vector in human clinical trials, modifying natural serotypes by peptide insertion has so far been less successful. Here, we now report on two capsid variants, MLIV.K and MLIV.A, both derived from a high-throughput in vivo AAV peptide display selection screen in mice. APPROACH AND RESULTS: The variants transduce primary murine and human hepatocytes at comparable efficiencies, a valuable feature in clinical development, and show significantly improved liver transduction efficacy, thereby allowing a dose reduction, and outperform parental AAV2 and AAV8 in targeting human hepatocytes in humanized mice. The natural heparan sulfate proteoglycan binding ability is markedly reduced, a feature that correlates with improved hepatocyte transduction. A further property that might contribute to the improved transduction efficacy is the lower capsid melting temperature. Peptide insertion also caused a moderate change in sensitivity to human sera containing anti-AAV2 neutralizing antibodies, revealing the impact of epitopes located at the basis of the AAV capsid protrusions. CONCLUSIONS: In conclusion, MLIV.K and MLIV.A are AAV peptide display variants selected in immunocompetent mice with improved hepatocyte tropism and transduction efficiency. Because these features are maintained across species, MLIV variants provide remarkable potential for translation of therapeutic approaches from mice to men.

Assessing the knowledge, attitude, and practice of frontline physicians in Egyptian university hospitals regarding pharyngitis and acute rheumatic fever: a cross-sectional study that calls for action.

BACKGROUND: Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) remain major public health issues. Although the primary and secondary prevention of RHD through appropriate management of bacterial pharyngitis and ARF are well-described in the literature, few studies address the knowledge, attitude, and practice (KAP) of developing countries. We aimed to evaluate the KAP of the frontline physicians in Egyptian university hospitals regarding pharyngitis and ARF. METHODS: We employed a cross-sectional design between September 1st, 2022, and January 31st, 2023 using a self-administered questionnaire in 21 Egyptian universities. The questionnaire was developed based on previous studies and recent guidelines and included four domains: sociodemographic data, knowledge, attitude, and practice regarding pharyngitis and ARF. We utilized both online (Google Forms) and paper surveys. Frontline physicians, including interns, residents, and assistant lecturers, were conveniently invited to participate. Furthermore, with the help of participating phycisians in recruiting their colleagues, we utilized the snowball method. Data were analyzed using IBM SPSS version 27 software. RESULTS: The final analysis included 629 participants, of whom 372 (59.1%) were males and 257 (40.9%) had direct contact with ARF patients. Most participants (61.5%) had a fair knowledge level while 69.5% had a fair level of practice regarding ARF and pharyngitis. Higher satisfactory knowledge levels were noted regarding pharyngitis (17.1% vs. 11.3%; p-value: 0.036) and ARF (26.8% vs. 18%; p-value: 0.008) among physicians dealing directly with ARF cases compared to physicians in departments not dealing directly with ARF cases. Physicians in Cairo region universities had significantly higher levels of satisfactory knowledge about ARF compared to Delta and Upper Egypt region universities (p = 0.014). Delta region universities showed significantly lower levels of practice compared to Cairo and Upper Egypt region universities (p = 0.027). The most frequently recognized barriers against health promotion were low socioeconomic status (90.3%) and lack of adequate public education (85.8%). CONCLUSIONS: Despite the fair knowledge and practice levels towards bacterial pharyngitis and ARF among participants, many gaps were still identified that might contribute to RHD prevalence. Educational interventions should be implemented by updating the local guidelines in Egypt for diagnosis and management based on the most recent guidelines.

Tomographic assessment of bone changes in atrophic maxilla treated by split-crest technique and dental implants with platelet-rich fibrin and NanoBone® versus platelet-rich fibrin alone: Randomized controlled trial.

BACKGROUND: This study evaluated the clinical benefits of adding NanoBone® with split-crest technique and simultaneous implant placement covered with platelet-rich fibrin membrane in horizontally deficient maxillary ridges in terms of crestal and horizontal bone changes and patient morbidity. METHODS: Forty patients indicated for maxillary ridge splitting and simultaneous implant placement were assigned randomly to the study groups: control group (Platelet Rich Fibrin membrane) and test group (Platelet Rich Fibrin membrane + Nanobone®). The Cone Beam Computed Tomography Fusion technique was utilized to assess crestal and horizontal bone changes after five months of the surgical procedure. Patient morbidity was recorded for one week post-surgical. RESULTS: Five months post-surgical, buccal crestal bone resorption was 1.26 ± 0.58 mm for the control group and 1.14 ± 0.63 mm for the test group. Lingual crestal bone resorption was 1.40 ± 0.66 mm for the control group and 1.47 ± 0.68 mm for the test group. Horizontal bone width gain was 1.46 ± 0.44 mm for the control group and 1.29 ± 0.73 mm for the test group. There was no significant statistical difference between study groups regarding crestal and horizontal bone changes and patient morbidity. CONCLUSIONS: The tomographic assessment of NanoBone® addition in this study resulted in no statistically significant difference between study groups regarding crestal and horizontal bone changes and patient morbidity. More randomized controlled clinical trials on gap fill comparing different bone grafting materials versus no grafting should be conducted. GOV REGISTRATION NUMBER: NCT02836678, 13th January 2017.

Cardiac MRI in patients with COVID-19 infection.

OBJECTIVE: COVID-19 infection is a systemic disease with various cardiovascular symptoms and complications. Cardiac MRI with late gadolinium enhancement is the modality of choice for the assessment of myocardial involvement. T1 and T2 mapping can increase diagnostic accuracy and improve further management. Our study aimed to evaluate the different aspects of myocardial damage in cases of COVID-19 infection using cardiac MRI. METHODS: This descriptive retrospective study included 86 cases, with a history of COVID-19 infection confirmed by positive RT-PCR, who met the inclusion criteria. Patients had progressive chest pain or dyspnoea with a suspected underlying cardiac cause, either by an abnormal electrocardiogram or elevated troponin levels. Cardiac MRI was performed with late contrast-enhanced (LGE) imaging, followed by T1 and T2 mapping. RESULTS: Twenty-four patients have elevated hsTnT with a median hsTnT value of 133 ng/L (IQR: 102 to 159 ng/L); normal value < 14 ng/L. Other sixty-two patients showed elevated hsTnI with a median hsTnI value of 1637 ng/L (IQR: 1340 to 2540 ng/L); normal value < 40 ng/L. CMR showed 52 patients with acute myocarditis, 23 with Takotsubo cardiomyopathy, and 11 with myocardial infarction. Invasive coronary angiography was performed only in selected patients. CONCLUSION: Different COVID-19-related cardiac injuries may cause similar clinical symptoms. Cardiac MRI is the modality of choice to differentiate between the different types of myocardial injury such as Takotsubo cardiomyopathy and infection-related cardiomyopathy or even acute coronary syndrome secondary to vasculitis or oxygen-demand mismatch. KEY POINTS: • It is essential to detect early COVID-related cardiac injury using different cardiac biomarkers and cardiac imaging, as it has a significant impact on patient management and outcome. • Cardiac MRI is the modality of choice to differentiate between the different aspects of COVID-related myocardial injury.

Bioactive compounds and biomedical applications of endophytic fungi: a recent review.

Human life has been significantly impacted by the creation and spread of novel species of antibiotic-resistant bacteria and virus strains that are difficult to manage. Scientists and researchers have recently been motivated to seek out alternatives and other sources of safe and ecologically friendly active chemicals that have a powerful and effective effect against a wide variety of pathogenic bacteria as a result of all these hazards and problems. In this review, endophytic fungi and their bioactive compounds and biomedical applications were discussed. Endophytes, a new category of microbial source that can produce a variety of biological components, have major values for study and broad prospects for development. Recently, endophytic fungi have received much attention as a source for new bioactive compounds. In addition, the variety of natural active compounds generated by endophytes is due to the close biological relationship between endophytes and their host plants. The bioactive compounds separated from endophytes are usually classified as steroids, xanthones, terpenoids, isocoumarins, phenols, tetralones, benzopyranones and enniatines. Moreover, this review discusses enhancement methods of secondary metabolites production by fungal endophytes which include optimization methods, co-culture method, chemical epigenetic modification and molecular-based approaches. Furthermore, this review deals with different medical applications of bioactive compounds such as antimicrobial, antiviral, antioxidant and anticancer activities in the last 3 years.

Sutureless versus conventional deep sclerectomy for management of open angle glaucoma.

INTRODUCTION: To compare sutureless deep sclerectomy to conventional deep sclerectomy regarding their lowering effect on intraocular pressure (IOP) in cases with open-angle glaucoma. METHODS: This is a prospective interventional randomized comparative study that included 60 eyes of 50 patients with open-angle glaucoma (OAG) who were indicated for surgical intervention. Patients were recruited from the glaucoma subspecialty clinic of the Cairo University teaching hospital and were divided into two groups: group A (underwent sutureless deep sclerectomy) and group B (underwent conventional deep sclerectomy). RESULTS: Both surgeries showed significant reduction of IOP all through the study period: in group A, mean reduction was 71.37%, 53.35%, 50.3%, and 44.33% at 1st day, 1 month, 3 months, and 6 months respectively, and in group B, mean reduction was 57.62%, 40.63%, 37.41%, and 31.68% at 1st day, 1 month, 3 months, and 6 months, respectively. Comparison between percentage of reduction in both groups showed no statistically significant difference. Also, use of anti-glaucoma medications dropped significantly at 6 months postoperatively in both groups with no significant difference between the 2 groups. Regarding reported complications, 12.9% in group A and 10.3% in group B presented with non-serious complications. One month postoperatively, UBM detected non-functioning blebs in 6.4% of group A and 3.4% in group B. Other cases with non-functioning blebs were detected at 3 and 6 months postoperatively, and all cases were managed. CONCLUSION: Sutureless deep sclerectomy seems to be a safe and effective modification, with significant IOP reduction in POAG.

Comparison of post-auricular and frontal bispectral index values obtained during renal surgeries.

BACKGROUND: The bispectral index (BIS) monitor is one of the EEG-derived monitoring techniques and well-established devices used to measure the depth of anesthesia. This study aimed to assess the agreement of BIS values based on the positions of either post-auricular or frontal sensors in individual patients undergoing renal surgeries while lateral positions at various stages of anesthesia. PATIENTS AND METHODS: 12 patients older than 18 years, ASA I-III patients scheduled for elective renal operations, two BIS were placed on each patient, one on each side of the post-auricular region and one across the forehead, and each sensor was connected to a different BIS monitor. We gathered three pieces of data at each of the six-time points: BIS score, signal quality index (SQI) score calculating the signal's strength and electromyography (EMG) score: before the onset of anesthesia (awake) when the eyelash reflex is lost (LOC), after intubation (intubation), following the initial surgical incision, each 30 min throughout the procedure (maintenance), and at the moment the patient's eyes open naturally after waking up from anesthesia (emergence). RESULTS: The overall BIS value at the frontal position was significantly higher than the post-auricular position (52.5 ± 22.2 and 52.1 ± 22.1, respectively, P = 0.010). On the other hand, the BIS value was comparable between the frontal and post-auricular positions at LOC, intubation, 60, 120, and 80 min and at emergence. A strong link between the two sensor positions, as indicated by the correlation coefficient (r = 0.607, P < 0.001), and the Bland-Altman analysis revealed a small mean difference (-1.8) and a low (9.0/- 12.5) limit of agreement, with just 4.3% of the readings falling outside of it during the anesthetic maintenance period. CONCLUSION: Acceptable variation in BIS data was observed when obtained from the two different sensor positions for clinical usage. The post-auricular BIS sensor system may be a suitable substitute for an impractical frontal setup. PROTOCOL REGISTRATION: The study was registered in clinicaltrials.gov on 11/07/2022 (trial registration number: NCT05451823).

miR-497 and 219 in blood aid meningioma classification.

INTRODUCTION: The current WHO classification and methylation status help predict meningioma recurrence and prognosis. However, up to date, there is no circulating biomarker showing clinical value in meningioma diagnosis or classification. Circulating miRNAs showed the potential to be used as cancer biomarkers in various tumours. This research evaluated specific miRNAs, miR-497 and miR-219, as convenient and efficient predictors of meningioma grades. METHODS: We studied serum and exosomal levels of miR-497 in 74 meningioma samples (WHO grade I = 25, WHO grade II = 25, and WHO grade III = 24) and 53 healthy controls. The serum level of miR-219 was studied in 56 meningioma samples WHO grade I = 22, WHO grade II = 14, and WHO grade III = 20). We used qPCR for miRNA quantification. We also tested two different normalisers, endogenous and external, and evaluated their impact on the diagnostic value of miR-497. RESULTS: The serum and exosomal levels of miR-497 distinguished meningioma from the control samples. Moreover, miR-497 was a suitable identifier for meningioma grade. When we combined miR-497 and miR-219, the efficacy of the combined biomarker was higher than miR-497 or miR-219 when used individually in meningioma classification. Both miR-497 and miR-219 showed a noticeable change with the methylation class of meningioma. CONCLUSION: This study shows that serum miR-497 is an effective and easy-to-measure biomarker for meningioma diagnosis and classification. Moreover, when we combined miR-497 and miR-219, the combined biomarker showed enhanced accuracy in meningioma classification. Furthermore, this is the first study to evaluate the correlation between serum circulating miRNA and the methylation status in meningioma.

Robot System Assistant (RoSA): Towards Intuitive Multi-Modal and Multi-Device Human-Robot Interaction.

This paper presents an implementation of RoSA, a Robot System Assistant, for safe and intuitive human-machine interaction. The interaction modalities were chosen and previously reviewed using a Wizard of Oz study emphasizing a strong propensity for speech and pointing gestures. Based on these findings, we design and implement a new multi-modal system for contactless human-machine interaction based on speech, facial, and gesture recognition. We evaluate our proposed system in an extensive study with multiple subjects to examine the user experience and interaction efficiency. It reports that our method achieves similar usability scores compared to the entirely human remote-controlled robot interaction in our Wizard of Oz study. Furthermore, our framework's implementation is based on the Robot Operating System (ROS), allowing modularity and extendability for our multi-device and multi-user method.

Ligand Nanocluster Array Enables Artificial-Intelligence-Based Detection of Hidden Features in T-Cell Architecture.

Protein patterning has emerged as a powerful means to interrogate adhering cells. However, the tools to apply a sub-micrometer periodic stimulus and the analysis of the response are still being standardized. We propose a technique combining electron beam lithography and surface functionalization to fabricate nanopatterns compatible with advanced imaging. The repetitive pattern enables a deep-learning algorithm to reveal that T cells organize their membrane and actin network differently depending upon whether the ligands are clustered or homogeneously distributed, an effect invisible to the unassisted human eye even after extensive image analysis. This fabrication and analysis toolbox should be useful, both together and separately, for exploring general correlation between a spatially structured subcellular stimulation and a subtle cellular response.

Interrater reliability and agreement of the liver imaging reporting and data system (LI-RADS) v2018 for the evaluation of hepatic lesions.

Purpose: The liver imaging reporting and data system (LI-RADS) is a structured reporting system that categorizes hepatic observations according to major imaging features and lesion size, with an optional ancillary features contribution. This study aimed to evaluate inter-reader agreement of dynamic magnetic resonance imaging (MRI) using LI-RADS v2018 lexicon. Material and methods: Forty-nine patients with 69 hepatic observations were included in our study. The major and ancillary features of each hepatic observation were evaluated by 2 radiologists using LI-RADS v2018, and the interreader agreement was allocated. Results: The inter-reader agreement of major LI-RADS features was substantial; κ of non-rim arterial hyperenhancement, non-peripheral washout appearance, and enhancing capsule was 0.796, 0.799, and 0.772 (p < 0.001), respectively. The agreement of the final LI-RADS category was substantial with κ = 0.651 (p < 0.001), and weighted κ = 0.786 (p < 0.001). The inter-reader agreement of the ancillary features was substantial to almost perfect (k range from 0.718 to 1; p < 0.001). An almost perfect correlation was noted for the hepatic lesion size measurement with ICC = 0.977 (p < 0.001). Conclusions: The major and ancillary features of the LI-RADS v2018, as well as the final category and lesions size, have substantial to almost perfect inter-reader agreement.

Corticosteroid nasal spray for recovery of smell sensation in COVID-19 patients: A randomized controlled trial.

OBJECTIVES: To evaluate the role of the topical corticosteroid, mometasone furoate, nasal spray in the treatment of post COVID-19 anosmia. METHODS: A prospective, randomized, controlled trial was conducted among patients with post COVID-19 anosmia. One hundred patients were randomly assigned to two groups; group I included 50 patients received mometasone furoate nasal spray in an appropriate dose of 2 puff (100 µg) once daily in each nostril for 3 weeks with olfactory training, group II included 50 patients were advised to keep on olfactory training only. The assessment of smell was done using (Visual Analog Scale from 0 to 10). All patients were initially evaluated after their recovery from COVID-19 and followed up for 3 weeks. The smell scores were recorded weekly and the duration of smell loss was recorded from the onset of anosmia till the full recovery. RESULTS: In both groups, the smell scores significantly improved by the end of the third week (P < 0.001). By comparing smell scores between both groups after 1 week, 2 weeks, and 3 weeks of treatment, there were no statistically significant differences between both groups. In group I, (62%) of patients completely recovered their sense of smell after 3 weeks of treatment, compared to (52%) of patients in group II (P = 0.31). CONCLUSION: The results suggested that using mometasone furoate nasal spray as a topical corticosteroid in the treatment of post COVID-19 anosmia offers no superiority benefits over the olfactory training, regarding smell scores, duration of anosmia, and recovery rates. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT04484493.

Optical coherence tomography angiography in juvenile open angle glaucoma: correlation between structure and perfusion.

PURPOSE: Juvenile open angle glaucoma (JOAG) is a type of glaucoma that occurs in patients younger than 40 years. Only a few studies have assessed vascular perfusion in JOAG and correlated it with structural damage. The aim of this study is to investigate vascular perfusion in JOAG by optical coherence tomography angiography (OCTA) and correlate it with structural damage, represented by retinal nerve fiber layer (RNFL) thinning. METHODS: This is a cross-sectional observational study of 25 eyes of patients with JOAG. All patients underwent full ocular examination and scanning by OCTA to measure parameters such as RNFL thickness, peripapillary and disk vascular density. RESULTS: Average superior and inferior RNFL thicknesses were 69.4 (± 22.1) and 70.4 (± 25.6) µm, whereas peripapillary and disk vascular densities were 38.2(± 10), and 39.1(± 12) % and superior and inferior vascular densities were 38.1(± 10.5) and 38.2(± 9.7) %. A strong positive correlation was found between the superior and inferior RNFL thickness and the vascular density of the peripapillary region, the disk and the superior and inferior vascular densities (p < 0.001 for all). CONCLUSION: OCTA parameters are strongly correlated with structural damage in JOAG patients. OCTA can serve as a helpful tool in the diagnosis and assessment of progression in JOAG and be utilized as a prognostic indicator, thus filling the defects and gaps present in other methods of assessment.

Montelukast combined with intranasal mometasone furoate versus intranasal mometasone furoate; a comparative study in treatment of adenoid hypertrophy.

OBJECTIVES: To evaluate the role of combined therapy using montelukast and intranasal mometasone furoate compared to intranasal mometasone furoate alone in treatment of adenoid hypertrophy regarding efficacy and recurrence rate. METHODS: The study included 100 children with adenoid hypertrophy, they were randomly assigned to two groups. Group I (50 patients) received combined therapy using montelukast and mometasone furoate nasal spray. Group II (50 patients) received only mometasone furoate nasal spray. Patients were treated for 3 months and observed for 3 months after stoppage of treatment. Patients were evaluated using symptoms scores, Adenoid/Nasopharyngeal ratio and endoscopic grading of adenoid hypertrophy. RESULTS: After 3 months of treatment, group I showed significant better scores of main symptoms than group II; (P = 0.001), (P = 0.019) and (P = 0.008) for rhinorrhea, mouth breathing and snoring respectively. The mean A/N ratio was 52.8 ± 11.3 in group I better than 62.88 ± 12.10 in group II (P < 0.001). Regarding the adenoid hypertrophy grading, significant reduction in size was found in group I in 34 (68%) patients better than in group II in 18 (36%) patients (P = 0.001). After further 3 months of follow up, the mean A/N ratio was 58.46 ± 10.05 in group I better than 66.36 ± 10.46 in group II (P < 0.001). Recurrence occurred in 8 (23.5%) cases out of 34 improved cases in group I better than 10 (55.5%) cases out of 18 cases in group II (P = 0.02). CONCLUSION: Combining oral montelukast with intranasal mometasone in treatment of adenoid hypertrophy provided better improvements and less recurrence in comparison with single therapy using intranasal mometasone alone.

Effect of filtering bleb dimensions on postoperative intraocular pressure in deep sclerectomy with collagen implant: a comparative study.

INTRODUCTION: The mechanisms of intraocular pressure (IOP) lowering in deep sclerectomy (DS) are multiple. Using collagen implants is one of the proposed mechanisms of DS success. It has been established to work via maintenance of subscleral decompression lake. However, the relation to conjunctival bleb formation is not fully established. METHOD: This study is a retrospective review of the records of 40 eyes of 30 patients with chronic open-angle glaucoma. Patients were divided into two groups; 20 eyes with DS using the Ologen implant (group A), and 20 eyes with DS without implant (group B). The records of UBM that was done for all patients 1 and 6 months after surgery were assessed for the extent, height of conjunctival bleb, depth of AC, the presence of intrascleral bleb and presence of collagen implant. RESULTS: Extent and height of conjunctival bleb by UBM in group A at 1 and 6 months were 3.46 ± 0.77 mm, 1.6 ± 0.38 and 3.71 ± 1.24 mm, 1.6 ± 0.64, respectively. In group B, they were 2.4 ± 1.12 mm, 0.99 ± 0.69 and 2.69 ± 1.77 mm, 0.81 ± 0.67 mm, respectively; the difference was statistically significant. Correlation using Pearson's correlation coefficient test showed significant negative correlation between extension of the bleb at 6 months and 3rd month postoperative IOP (r = - 0.447, P value 0.048) and significant negative correlation of the height at 6 months to 5th month IOP (r = - 0.491, P 0.028). CONCLUSION: Using collagen implant in DS significantly increases conjunctival bleb dimensions, which reflects on lower postoperative IOP.

Remote Welfare Monitoring of Rodents Using Thermal Imaging.

Animal research has always played a crucial role in various medical and scientific breakthroughs. They offer, inter alia, insights into diseases mechanisms, genetic predisposition to a disease, and drug therapy. However, the use of animals for medical research is a cause of major controversies and debates in modern science. To warrant high bioethical standards, new directives have been being adopted to replace animal research whenever possible, to reduce the number of animals, and to refine the procedures to minimize stress and pain. Here, we present two new approaches, based on thermal imaging (a remote and passive technology), to assess respiratory rate (RR) as well as exploratory behavior and general activity in rodents. In animal research, these parameters are gold standards for welfare assessment. The approaches were validated in a study conducted with both rats and mice. To test the feasibility of our algorithm to estimate RR, thermal videos from anesthetized rodents were acquired. The capability of the second approach to monitor activity was tested with videos of Open Field tests. Regarding RR, a high agreement between thermal imaging and gold standard (electrocardiography-derived RR) was achieved. The mean relative error averaged 0.50 ± 0.15 breaths/min and 4.55 ± 2.94 breaths/min for rats and mice, respectively. The second approach was capable of monitoring and tracking the activity of the rodents very well. This paper demonstrates that thermal imaging is a promising and relevant alternative for monitoring of RR and activity in rodents, thus contributing to the remote assessment of animal welfare.

The Ambivalent Function of YAP in Apoptosis and Cancer.

Yes-associated protein, a core regulator of the Hippo-YAP signaling pathway, plays a vital role in inhibiting apoptosis. Thus, several studies and reviews suggest that yes-associated protein is a good target for treating cancer. Unfortunately, more and more evidence demonstrates that this protein is also an essential contributor of p73-mediated apoptosis. This questions the concept that yes-associated protein is always a good target for developing novel anti-cancer drugs. Thus, the aim of this review was to evaluate the clinical relevance of yes-associated protein for cancer pathophysiology. This review also summarized the molecules, processes and drugs, which regulate Hippo-YAP signaling and discusses their effect on apoptosis. In addition, issues are defined, which should be addressed in the future in order to provide a solid basis for targeting the Hippo-YAP signaling pathway in clinical trials.

Effect of Two Remineralizing Agents on Initial Caries-like Lesions in Young Permanent Teeth: An in Vitro Study.

AIM: To compare the effect of nano-hydroxyapatite (9000 ppm F) and casein phosphopeptide-amorphous calcium phosphate fluoride (900 ppm F) pastes on initial enamel carious lesions of young permanent teeth. MATERIALS AND METHODS: Sixty extracted young premolars with a standardized window on enamel were immersed in a demineralizing solution for 48 hours to produce subsurface enamel lesions. They were divided into three groups according to remineralizing agents (n = 20) group I: nano-hydroxyapatite paste; group II: casein phosphopeptide-amorphous calcium phosphate fluoride paste; and group III: control (without an agent). The enamel surface microhardness (SMH) was measured at baseline, after the incipient enamel lesion, and after treatment. Additional twenty young premolars were selected and prepared as mentioned above for surface morphology evaluation by scanning electron microscope (SEM). RESULTS: No significant difference was found in mean surface microhardness in teeth treated with nano-hydroxyapatite paste and those treated with casein phosphopeptide-amorphous calcium phosphate fluoride p = 0.26. SEM showed improvement in surface defects of demineralized enamel in the two test groups. CONCLUSION: Nano-hydroxyapatite and casein phosphopeptide-amorphous calcium phosphate fluoride pastes were effec -tive in rehardening the initial enamel caries lesions in young permanent teeth. CLINICAL SIGNIFICANCE: The best strategy for caries management is to focus on the methods of improving the reminer-alization process with the aid of the remineralizing agents. The current study compared the remineralizing effect of two remineralizing agents. Within the limitations of the study, both remineralizing agents were effective for remineralization of early caries-like lesions.

CspE is Overproduced by Temperature Downshift in the Acinetobacter johnsonii DBP-3.

The denitrifying bacterium Acinetobacter johnsonii strain DBP-3 which was capable of removing phosphate, nitrate, and ammoniacal salt is psychrotolerant, whereas, the cold shock response mechanisms or the cold shock proteins (Csps) was unclear. In this article, the optimal growth temperature (25 °C) and cold shock temperature (7.5 °C) were determined firstly by an Arrhenius plot of the growth of the strain DBP-3. Then, among the seven cold shock-like protein genes which were cloned and identified referenced by A. johnsonii SH046 genome, qRT-PCR and shotgun-LTQ mass spectrometry showed that Csp3 and Csp4 were overexpressed under cold shock condition. Furthermore, Western blotting confirmed the result with the antibodies against Csp3 and Csp4 prepared by ourselves. Finally, the phylogenetic analysis showed that the similarity percent between Csp3 and Csp4 was 76.85 %, and Csp3 and Csp4 belonged to CspE family. The results indicated that CspE is overproduced by temperature downshift and may play an important role in the psychrotolerant process of strain DBP-3.