Incorporation of Protecting Groups in Organic Chemistry: A Mini-Review.

The approach of utilizing protecting groups (PGs) in organic chemistry has led to the successful syntheses of an array of useful organic compounds. This strategy has also addressed some of the complexities associated with many organic reactions. These PGs find useful applications in simple and complex reactions that involve the synthesis of large organic compounds such as peptides, and oligosaccharides. The fundamental role of PGs is to prevent undesired reactions that could hinder the progress or completion of such reactions. Ideal PGs must be utilized in this regard to achieve the desired objectives. This review describes the diverse protecting groups found in the literatures, the functional moieties for the protection, deprotection strategies, and their relevant applications in organic synthesis.

Assessment of Microgap and Microbial Leakage of Two Different Implant-abutment Interfaces: An In Vitro Study.

AIM: The purpose of the current study was to evaluate Titanium and Bioneck TRI implant-abutment interfaces for microgaps and microbiological leakage. MATERIALS AND METHODS: In this in vitro experiment, 40 dental implants were split into two groups, each of which had 20 samples. Group I: Titanium dental implant, group II: Bioneck TRI. E. coli strain was cultivated in MacConkey media for 24 hours at 37°C. To achieve a bacterial concentration of 1 × 108 colony-forming units per mL at 0.5 scale of MacFarland, the brain-heart infusion (BHI) broth was injected. The CFU count was done to evaluate the microbial leakage. The parts were first submerged, carefully cleaned in an ultrasonic bath, and then installed using a digital torque meter with a 20 N/cm preload. These were attached to a stub of approximately 13 mm using carbon tape, and the microgap evaluation was performed using a scanning electron microscope at a magnification of x1000. Unpaired t-test was used for the calculated data's statistical analysis. The p-value less than 0.05 was considered as statistically significant. RESULTS: The maximum microbial leakage was in Bioneck TRI implants (10000 ± 0.01) followed by Titanium dental implants (8.60 ± 3.16). The mean difference was 9991.40 and there was a statistically significant difference found between the two different groups. The maximum microgap was found in the Bioneck TRI implants (9.72 ± 0.96), followed by Titanium dental implant (6.82 ± 1.10) and there was a statistically significant difference was found between the groups (p < 0.001). CONCLUSION: The present study concluded that the microorganisms can infiltrate the microgap between the implant and abutment interface. When compared with Titanium dental implants, Bioneck TRI implants showed significantly higher levels of microbial leakage. CLINICAL SIGNIFICANCE: A microgap between the implant and abutment connection might operate as a bacterial source, may produce inflammation, even osseointegration in danger, and subsequently alter clinical and histological parameters. Therefore, having an understanding of the compatible components aids in overcoming treatment planning challenges.

Effect of Fluoridated Mouthwashes on Corrosion Property of Orthodontic Appliances: A Narrative Review.

OBJECTIVE: To analyze the effects of various fluoride agents on metallic orthodontic materials. DESIGN: PubMed, Google Scholar, and Embase were searched using keyword combinations such as fluoride mouthwash and orthodontic appliance and corrosion, fluoride and fixed appliance, and metal degradation. RESULTS: Of 315 articles, 20 were selected for inclusion in the review. All types of fluoride agents, especially the acidulated form of fluoride, seemed to influence the corrosion of orthodontic metallic appliances. CONCLUSION: Since most of the studies reported suggest that fluoride ions are capable of causing corrosion of metallic orthodontic appliances, attention should be paid while prescribing fluoride agents for orthodontic patients. The degree of corrosion seems to be directly correlated with the acidity of the medium and the concentration of fluoride ions. Co-Cr brackets are resistant to corrosion by fluoride while stainless steel and Ti brackets are susceptible. CLINICAL SIGNIFICANCE: It allows making the right choice while choosing the orthodontic brackets in relation to their susceptibility to corrosion by fluoride ions.

A Possible Novel Protective Effect of Piceatannol against Isoproterenol (ISO)-Induced Histopathological, Histochemical, and Immunohistochemical Changes in Male Wistar Rats.

Dry mouth is characterized by lower saliva production and changes in saliva composition. In patients with some salivary gland function remaining, pharmaceutical treatments are not recommended; therefore, new, more effective methods of promoting saliva production are needed. Hence, this study aimed to provide an overview of the histological changes in the salivary gland in the model of isoproterenol (ISO)-induced degenerative changes in male Wistar rats and to evaluate the protective effect of piceatannol. Thirty-two male Wistar rats were randomly divided into four groups: the control group, the ISO group, and the piceatannol (PIC)-1, and -2 groups. After the third day of the experiment, Iso (0.8 mg/100 g) was injected intraperitoneally (IP) twice daily into the animals. PIC was given IP in different daily doses (20 and 40 mg/kg) for three days before ISO and seven days with ISO injection. The salivary glands were rapidly dissected and processed for histological, histochemical, immunohistochemical (Ki-67), and morphometric analysis. Upon seven days of treatment with ISO, marked hypertrophy was observed, along with an increased number of positive Ki-67 cells. Proliferation was increased in some endothelial cells as well as in ducts themselves. Despite the significant decrease in proliferation activity, the control group did not return to the usual activity level after treatment with low-dose PIC. Treatment with a high dose of PIC reduced proliferative activity to the point where it was substantially identical to the results seen in the control group. An ISO-driven xerostomia model showed a novel protective effect of piceatannol. A new era of regenerative medicine is dawning around PIC's promising role.

Entrectinib: A New Selective Tyrosine Kinase Inhibitor Approved for the Treatment of Pediatric and Adult Patients with NTRK Fusionpositive, Recurrent or Advanced Solid Tumors.

BACKGROUND: Entrectinib is a highly potent ATP-competitive and selective inhibitor of tyrosine kinases - Trk A B C, ALK, and ROS1. It was developed by Roche and initially approved in Japan in 2019 to treat pediatric and adult patients with NTRK fusionpositive, recurrent, or advanced solid tumors. In August 2019, entrectinib received accelerated approval by the U.S FDA for this indication. It is also the first FDA-approved drug designed to target both NTRK and ROS1. OBJECTIVE: We aim to summarize recent studies related to the synthesis, mechanism of action, and clinical trials of the newly approved selective tyrosine kinase inhibitor entrectinib. METHODS: We conduct a literature review of the research studies on the new highly-potent small-molecule entrectinib. CONCLUSION: Entrectinib, based on three clinical studies (ALKA, STARTRK-1, and STARTRK-2), was well tolerated, with a manageable safety profile. It induced clinically meaningful responses in recurrent or advanced solid tumors associated with NTRK fusion- positive or ROS1+ NSCLC. It demonstrated substantial efficacy in patients with CNS metastases.

Knowledge, Attitudes, and Practices of Dental Healthcare Workers toward Hepatitis B Virus in Khartoum/Sudan.

OBJECTIVE: The aim of the present study is to evaluate dental healthcare workers' knowledge, attitudes, and practices toward hepatitis B infection. MATERIALS AND METHODS: This study was a cross-sectional self-administered, structured questionnaire survey that was conducted in Khartoum/Sudan. The questionnaire was completed by 177 dental healthcare providers who practice in public dental clinics in Khartoum state. The completion rate was 100%. RESULTS: The study participants showed relatively acceptable knowledge of hepatitis B virus (HBV) infection. The majority (98.3%) were familiar with hepatitis B infection. About 93% answered correctly that blood, blood products, and needles/sharps are the route of transmission of HBV. About 65.5% completed HBV vaccination. About 59.3% had a history of needle sticks and only 16% reported their injury. Dentists and nurses almost had the same knowledge, but dentists were slightly having better knowledge in some aspects. Statistical Package for Social Sciences (SPSS) version 20 was used. Chi-square test was used to determine the relationship between categorical variables. CONCLUSION: Most of the study participants were aware of HBV infection, routes of transmission, prevention, and necessity of vaccination, but they are deficient in some areas, like needle-stick injury protocol and post-exposure prophylaxis (PEP). The study revealed a low level of HBV vaccination coverage rate. Further strategies for preventing workplace exposure, training programs on HBV infection, including PEP, and increasing the vaccination coverage rate of all healthcare workers are highly recommended. CLINICAL SIGNIFICANCE: Dental healthcare workers are at high risk of acquiring hepatitis B infection. The majority of exposure in dentistry is preventable. Understanding the knowledge and awareness of dental health toward hepatitis B is crucial to design and apply preventive measures to control transmission and potential complications.

Epitope-Based Peptide Vaccine against Glycoprotein G of Nipah Henipavirus Using Immunoinformatics Approaches.

BACKGROUND: Nipah belongs to the genus Henipavirus and the Paramyxoviridae family. It is an endemic most commonly found at South Asia and has first emerged in Malaysia in 1998. Bats are found to be the main reservoir for this virus, causing disease in both humans and animals. The last outbreak has occurred in May 2018 in Kerala. It is characterized by high pathogenicity and fatality rates which varies from 40% to 70% depending on the severity of the disease and on the availability of adequate healthcare facilities. Currently, there are no antiviral drugs available for NiV disease and the treatment is just supportive. Clinical presentations for this virus range from asymptomatic infection to fatal encephalitis. OBJECTIVE: This study is aimed at predicting an effective epitope-based vaccine against glycoprotein G of Nipah henipavirus, using immunoinformatics approaches. METHODS AND MATERIALS: Glycoprotein G of the Nipah virus sequence was retrieved from NCBI. Different prediction tools were used to analyze the epitopes, namely, BepiPred-2.0: Sequential B Cell Epitope Predictor for B cell and T cell MHC classes II and I. Then, the proposed peptides were docked using Autodock 4.0 software program. Results and Conclusions. The two peptides TVYHCSAVY and FLIDRINWI have showed a very strong binding affinity to MHC class I and MHC class II alleles. Furthermore, considering the conservancy, the affinity, and the population coverage, the peptide FLIDRINWIT is highly suitable to be utilized to formulate a new vaccine against glycoprotein G of Nipah henipavirus. An in vivo study for the proposed peptides is also highly recommended.

Vitamin D level and its determinants among Sudanese Women: Does it matter in a sunshine African Country?

BACKGROUND: Vitamin D deficiency is a worldwide concern. The aim of the current study was to determine the vitamin D level and its contributing factors in Sudanese women. METHODS: In this cross-sectional study, 251 Sudanese women attending Family Health Centers in Khartoum, Sudan were interviewed. Following the exclusion of confounding factors, samples from 190 women were analzsed. Serum 25 hydroxyvitamin D "25(OH) D" was quantified using competitive electrochemiluminescence immunoassay. RESULTS: Participants' age ranged from 18 to 85 years with a mean age (±SD) of 40.2 (±14.06) years. The mean (±SD) vitamin D level was 13.4 (±6.72) ng/ml, ranged 3.00-36.5 ng/ml and the median was 12.7 ng/mL. In total, 157 out of 190 (82.6%) had vitamin D serum levels below 20 ng/ml (deficient); of whom, 52 (27.4%) were in the age group 21-30 years (P value = 0.228). The correlation between vitamin D level and residence outside Khartoum, sun-exposed face and hands, and face and limbs in comparison with being completely covered were found to be statistically significant (p values 0.008, 0.023, and 0.036). CONCLUSION: This study displayed a high percentage (82.6%.) of vitamin D deficiency among women in Sudan, and this in part may indicate that sunshine alone cannot guarantee vitamin D sufficiency in the tropics. Family physicians in tropical countries should screen those with clinical presentations related to vitamin D deficiency.

Serum vitamin D level, sun-exposed area, dietary factors, and physical activity as predictors of invasive breast cancer risk among Sudanese women: A case-control study.

BACKGROUND: The role of vitamin D in the development, progression, and prognosis of breast cancer, though widely studied worldwide, has been inconclusive. This study intended to assess the role of some factors (including serum vitamin D level, sun-exposed area, dietary factors, and physical activity) as predictors of the development of invasive breast cancer (IBC) among Sudanese women. METHODS: A case-control study was conducted on 200 Sudanese women (100 with newly diagnosed IBC and 100 matched healthy females). Serum 25-hydroxyvitamin D was measured through a competitive electrochemiluminescence immunoassay. Matching analysis was adopted by R version 3.4.1 making use of the "MatchIt" package for calculating propensity scores to build a confounder-adjusted, multiple generalized, linear logistic regression model. RESULTS: Participants' age ranged from 28 to 85 years with a mean [±standard deviation (SD)] of 48.10 (±12.11) years. The mean (±SD) serum vitamin D level was 12.97 (±8.60) and 13.79 (±6.79) ng/mL in breast cancer and noncancer Sudanese women, respectively [P = 0.013; odds ratio (OR) 0.862; 95% confidence interval (CI) 0.766-0.969; ß = 0.149)]. Sun-exposed area (P = 0.038; OR 0.013; 95% CI 0.000-0.782; ß = 4.339) is significantly and negatively associated with breast cancer development. While moderate physical activity (P = 0.0008; OR 2625.430; 95% CI 26.647-258673.001; ß = 7.873) is significantly and positively associated with IBC risk. Occasional consumption of milk, dairy products, eggs, and fish reduces the risk of developing IBC by 78.1%, 75.0%, 78.4%, and 76.4%, respectively. CONCLUSION: The higher the plasma vitamin D level by one unit, the lower the risk of breast cancer by 13.84%. Sedentary lifestyle, reduced sun-exposed skin area, and low serum vitamin D levels can be considered as predictors of IBC. Encouraging moderate physical activity and consumption of certain foods may, in part, decrease the precipitating risks of breast cancer. More studies and research are needed to confirm these findings.