Development of engineered transferosomal gel containing meloxicam for the treatment of osteoarthritis.

OBJECTIVE: Among the musculoskeletal conditions, osteoarthritis (OTA) contributes significantly to years lived with disability. In the present investigation, meloxicam (MLX) incorporated transferosomal gel was explored to address the problem of OTA as newer lipidic drug delivery system. MATERIAL AND METHODS: Classical lipid film hydration technique was utilized to formulate different transferosomal formulations. Different transferosomal formulations were prepared by varying the molar ratio of phospholipon-90H (phosphodylcholine) to DSPE (50:50, 60:40, 70:30, 80:20, and 90:10) and per batch, 80 mg of total lipid was used. The quality control parameters such as entrapment efficiency, particle size and morphology, polydispersity and surface electric charge, in vitro drug release, ex vivo permeation and stability were measured. RESULTS: The optimized transferosomal formulations revealed a small vesicle size (121±12 nm) and greater MLX entrapment (68.98±2.3 %). Transferosomes mediated gel formulation MLX34 displayed pH (6.3±0.2), viscosity (6236± 12.3 cps), spreadability (13.77±1.77 gm.cm/sec) and also displayed sustained release pattern of drug release (81.76±7.87 % MLX released from Carbopol-934 gel matrix in 24 h). MLX34 revealed close to substantial anti-inflammatory response, with ∼81% inhibition of TNF-α in 48 h. Physical stability analysis concluded that refrigerator temperature was the preferred temperature to store transferosomal gel. CONCLUSION: MLX loaded transferosomes containing gel improved the skin penetration and therefore resulted into increased inhibition of TNF-α level.

Comparison of Various Commonly Used Luting Cements on the Success of Composite Inlays Assessed by the Levels of the Microleakage-An In vitro Study.

Introduction: Indirect composite restoration is one of the commonly followed procedures in the posterior teeth. The success of this is dependent on many factors, one being the luting cement. Hence, the current study explores the microleakage of the two luting cements at 2 different times. Materials and Methods: Eighty extracted human teeth were taken, and class II cavities were made that were to receive the composite inlays. They were grouped as supragingival and subgingival, which for further divided as were further subdivided to be observed for marginal leakage at cervical and occlusal margins, at the end of a day and 1 month. Each group had ten specimens. The luting cements that were evaluated were Variolink N and RelyX Unicem. After the composite inlay restoration was done for all the specimens, the sections were put on slides, and a stereomicroscope was used to measure the amount of dye penetration. Leakage was evaluated and compared using Mann-Whitney U test. Results: At the end of 1 day, there was no significant alteration in the microleakage in the occlusal or cervical regions for either region supragingivally or subgingivally between the two luting cements. Significant difference between the two cements at the cervical borders at the end of a month was seen for both the margins. When compared supragingivally and subgingivally at the end of 1 day or at the end of 1 month, there was not a significant difference for any of the cements. Conclusion: Within the constraints of the current investigation, it can be said that there was similar microleakage for both Variolink N and RelyX Unicem at the conclusion of a day's storage time. After a 1-month storage period, RelyX Unicem showed more cervical microleakage than Variolink N.

Comparison of Different Betadine and Saline Combinations on Microorganisms: An Original Research.

Introduction: Pathogenic bacteria in the oral cavity or a physiological microbiome imbalance can cause or maintain disease. Thus, this work examined a novel betadine-saline combination for antibacterial and antifungal activities. Materials and Methods: This study was in vitro. Betadine, saline, and their mixtures were tested for Bacillus subtilis, Staphylococcus aureus (gram-positive), Pseudomonas aeruginosa, Escherichia coli, and Aspergillus niger (gram-negative). Pour plate and disc diffusion methods were used to test CFUs, DZI, and RZI for various agent combinations. Results: For Lactobacillus acidophilus, Betadine 90% + saline 10% had the greatest DZI and RZI at 24 and 12 mm, respectively. For E. coli, Betadine 50% + saline 50% had the highest at 16 and 8 mm. Betadine 60% + saline 40% had 14 mm RZI and the highest antifungal activity. Conclusion: The novel betadine-saline antibacterial and antifungal combination performed well. In vivo research should confirm the existing findings.

Comparison of the Conventional and Laser Etching on the Bonding of the Orthodontic Brackets: An Original Research.

Background: Acid etching enamel improves resin-enamel adhesion and adhesive characteristics, but has pros and cons. The effects of laser etching on the bonding of orthodontic brackets vary depending on the wavelength, power output, exposure duration, and energy delivered. Materials and Methods: This study used a new 1064-nm diode laser to irradiate 30 freshly extracted human premolars. They were divided into three groups: group A, group B, and group C. Acid etching was used for 1 min to bond bracket to tooth surface, and Indian ink was used for 30 s. Group C uses acid etching for 1 min following 30 s of laser irradiation with Indian ink. Results: In comparison to the other groups, group C's acid etching after laser irradiation has considerably stronger bond strength (P = 0.05). Orthodontic brackets in group B exhibited considerably poorer shear bond strength than those in the other groups. Conclusion: Acid etching improves the adhesion of orthodontic composite resin to human enamel following laser irradiation, but can interfere with the adhesion of composite resin.

Auto-PAP Titration Efficacy in Obstructive Sleep Apnea: A Single-Center Experience.

Introduction: Obstructive sleep apnea, often known as OSA, is a sleep-related breathing disease that, if not treated, can lead to serious disabilities or even death. Continuous positive airway pressure (CPAP) is the therapy technique that is suggested for treating severe and moderate OSA. An auto/manual CPAP titration study can be used to determine the appropriate pressure that must be maintained to treat this condition. The motive of this research is to appraise the effectiveness among OSA patients for the auto-PAP titrations. Methodology: A cross-sectional clinical prospective study was conducted at the tertiary care center. Subjects who underwent auto-PAP titration and had a diagnosis of moderate and sever OSA were included. They were evaluated for the efficacy of auto-PAP titration and other demographic features and their association with the titration efficacy. The values were compared for statistical significance. Results: The findings of the study showed that fifty percent of the cohort showed optimal titration, forty percent showed good titration, ten percent showed suitable titration, and none fell into the unacceptable group. Conclusion: According to the findings, using auto-PAP was associated with positive results in those with moderate and severe OSA. There is evidence to suggest that unattended auto-PAP titration is a very successful technique that might be regarded as a substitute for attended CPAP titrations. This would result in a reduction in the amount of labor required and the price.

Lab on chip based self-adjustable liposomes for rapid wound healing: An in depth in vitro, in vivo and higher dose toxicity investigation.

Thanks to microfluidic technology, different nano-delivery systems are becoming clinically viable. Using a novel and rapid microfluidic hydrodynamic focusing (MHF) method (lipids on chip) we developed self-adaptable liposomes (SLs) containing cefpodoxime proxetil (CP) for the treatment of skin infections caused by Staphylococcus aureus. SLs were optimized using different flow rate ratios in the MHF method and the final formulation CPT3 was found to be the best in terms of particle size (68.27 ± 01.15 nm), % entrapment efficiency (% EE: 82 ± 1.5), polydispersity (PDI: 0.2 ± 0.012), and degree of deformability (DOD: 4.7 ± 0.18 nm). Rats (Sprague Dawley) treated with a self-adaptable CPT3 liposomal formulation recuperate skin injury, exhibited reduced bacterial counts (<106 CFU/mL) in the wounded region, and completely restored (100 %) on day 21. Rat survival, in vivo dermal pharmacokinetics and ex vivo-in vivo relationship were also investigated. Rats treated with an even 10-fold higher dose (100 mg/kg/day) of CP using an equivalent CPT3 formulation did not show any symptoms of toxicity as revealed by hematological, biochemical, and internal organ assessment observations. Finally, the developed CPT3 formulation with special interest in patients with high-risk skin injuries not only delivered CP in a controlled manner but was also clinically effective and safe as it did not produce any serious adverse events even at 10× higher doses in the infected rats.

MFP1 defines the subchloroplast location of starch granule initiation.

Starch is one of the major carbohydrate storage compounds in plants. The biogenesis of starch granules starts with the formation of initials, which subsequently expand into granules. Several coiled-coil domain-containing proteins have been previously implicated with the initiation process, but the mechanisms by which they act remain largely elusive. Here, we demonstrate that one of these proteins, the thylakoid-associated MAR-BINDING FILAMENT-LIKE PROTEIN 1 (MFP1), specifically determines the subchloroplast location of initial formation. The expression of MFP1 variants "mis"-targeted to specific locations within chloroplasts in Arabidopsis results in distinctive shifts in not only how many but also where starch granules are formed. Importantly, "re" localizing MFP1 to the stromal face of the chloroplast's inner envelope is sufficient to generate starch granules in this aberrant position. These findings provide compelling evidence that a single protein MFP1 possesses the capacity to direct the initiation and biosynthesis machinery of starch granules.

Role of bio-flavonols and their derivatives in improving mitochondrial dysfunctions associated with pancreatic tumorigenesis.

Mitochondria, a cellular metabolic center, efficiently fulfill cellular energy needs and regulate crucial metabolic processes, including cellular proliferation, differentiation, apoptosis, and generation of reactive oxygen species. Alteration in the mitochondrial functions leads to metabolic imbalances and altered extracellular matrix dynamics in the host, utilized by solid tumors like pancreatic cancer (PC) to get energy benefits for fast-growing cancer cells. PC is highly heterogeneous and remains unidentified for a longer time because of its complex pathophysiology, retroperitoneal position, and lack of efficient diagnostic approaches, which is the foremost reason for accounting for the seventh leading cause of cancer-related deaths worldwide. PC cells often respond poorly to current therapeutics because of dense stromal barriers in the pancreatic tumor microenvironment, which limit the drug delivery and distribution of antitumor immune cell populations. As an alternative approach, various natural compounds like flavonoids are reported to possess potent antioxidant and anticancerous properties and are less toxic than current chemotherapeutic drugs. Therefore, we aim to summarize the current state of knowledge regarding the pharmacological properties of flavonols in PC in this review from the perspective of mitigating mitochondrial dysfunctions associated with cancer cells. Our literature survey indicates that flavonols efficiently regulate cellular metabolism by scavenging reactive oxygen species, mitigating inflammation, and arresting the cell cycle to promote apoptosis in tumor cells via intrinsic mitochondrial pathways. In particular, flavonols proficiently inhibit the cancer-associated proliferation and inflammatory pathways such as EGFR/MAPK, PI3K/Akt, and nuclear factor κB in PC. Overall, this review provides in-depth evidence about the therapeutic potential of flavonols for future anticancer strategies against PC; still, more multidisciplinary human interventional studies are required to dissect their pharmacological effect accurately.

Implementing a chest X-ray artificial intelligence tool to enhance tuberculosis screening in India: Lessons learned.

Artificial Intelligence (AI) based chest X-ray (CXR) screening for tuberculosis (TB) is becoming increasingly popular. Still, deploying such AI tools can be challenging due to multiple real-life barriers like software installation, workflow integration, network connectivity constraints, limited human resources available to interpret findings, etc. To understand these challenges, PATH implemented a TB REACH active case-finding program in a resource-limited setting of Nagpur in India, where an AI software device (qXR) intended for TB screening using CXR images was used. Eight private CXR laboratories that fulfilled prerequisites for AI software installation were engaged for this program. Key lessons about operational feasibility and accessibility, along with the strategies adopted to overcome these challenges, were learned during this program. This program also helped to screen 10,481 presumptive TB individuals using informal providers based on clinical history. Among them, 2,303 individuals were flagged as presumptive for TB by a radiologist or by AI based on their CXR interpretation. Approximately 15.8% increase in overall TB yield could be attributed to the presence of AI alone because these additional cases were not deemed presumptive for TB by radiologists, but AI was able to identify them. Successful implementation of AI tools like qXR in resource-limited settings in India will require solving real-life implementation challenges for seamless deployment and workflow integration.

Protective role of CXCR7 activation in neonatal hyperoxia-induced systemic vascular remodeling and cardiovascular dysfunction in juvenile rats.

Neonatal hyperoxia induces long-term systemic vascular stiffness and cardiovascular remodeling, but the mechanisms are unclear. Chemokine receptor 7 (CXCR7) represents a key regulator of vascular homeostasis and repair by modulating TGF-ß1 signaling. This study investigated whether pharmacological CXCR7 agonism prevents neonatal hyperoxia-induced systemic vascular stiffness and cardiac dysfunction in juvenile rats. Newborn Sprague Dawley rat pups assigned to room air or hyperoxia (85% oxygen), received CXCR7 agonist, TC14012 or placebo for 3 weeks. These rat pups were maintained in room air until 6 weeks when aortic pulse wave velocity doppler, cardiac echocardiography, aortic and left ventricular (LV) fibrosis were assessed. Neonatal hyperoxia induced systemic vascular stiffness and cardiac dysfunction in 6-week-old rats. This was associated with decreased aortic and LV CXCR7 expression. Early treatment with TC14012, partially protected against neonatal hyperoxia-induced systemic vascular stiffness and improved LV dysfunction and fibrosis in juvenile rats by decreasing TGF-ß1 expression. In vitro, hyperoxia-exposed human umbilical arterial endothelial cells and coronary artery endothelial cells had increased TGF-ß1 levels. However, treatment with TC14012 significantly reduced the TGF-ß1 levels. These results suggest that dysregulation of endothelial CXCR7 signaling may contribute to neonatal hyperoxia-induced systemic vascular stiffness and cardiac dysfunction.

An efficient one-pot synthesis and docking studies of bioactive new antiproliferative dispiro[oxindole/acenaphthylenone‒benzofuranone] pyrrolidine scaffolds.

A new and efficient method has been developed to synthesize dispiro[oxindole/acenaphthylenone-benzofuranone]pyrrolidine compounds. This is done by triggering the 1,3-dipolar cycloaddition reaction of azomethine ylides by reacting isatin/acenaphthoquinone with L-picolinic acid/L-proline/sarcosine/L-thioproline/tetrahydroisoquinolines, in a highly regioselective manner in an ionic liquid [DBU][Ac] with 4'-chloro-auron[2-(4-chlorobenzylidene)benzofuran-3(2H)-one]. Single-crystal X-ray diffraction data support the proposed structures of the new compounds. The heterocycles derived from amino acids such as L-picolinic acid, L-proline, and L-thioproline showed significant inhibitory effects against six human solid tumors, including lung, breast, cervix, colon, and others. These new structures were also tested in the active sites of the MDM2 receptor to further study their antiproliferative effects.

Niosomes based formulation containing tenoxicam: A newer solution for the rheumatic diseases.

OBJECTIVE: This investigation aimed to explore the potential of non-ionic surfactant based niosomal vesicles encapsulating tenoxicam (TN; anti-rheumatic drug) for the treatment of rheumatic diseases. MATERIAL AND METHODS: Mechanical dispersion technique with controlled pressure was employed to prepare different niosomal formulations. The effects of different ratios of surfactant (span-60), lipid, and sodium deoxycholate on noisome's physicochemical properties have been examined. Moreover, inhibition of TNF-α in lipopolysaccharide-activated cultured Human leukemia monocytic (THP-1) cells were demonstrated to assess the in vitro inflammation profile. Finally, the optimized niosomal formulation (TN3) was prepared in gel matrix consist of carbopol 934 (termed as TN34) and stability was also tested at 4±2 ÌŠC, 25±2 ÌŠC, 37±2 ÌŠC and 45±2 ÌŠC for 6 months. RESULTS: The optimized niosomal formulation exhibited a small vesicle size (165±14nm) and high drug encapsulation (79.64±1.5%). Niosomal gel formulation TN34 showed pH (6.7), viscosity (6810±3.34 cps), spreadability (19.11±1.87gm.cm/sec) and also displayed sustained release pattern of drug release (98.16±0.07% TN released from gel matrix in 24h) in vitro release study. TN34 exhibited substantial anti-inflammatory response, with ∼75% inhibition of TNF-α in 48h. Stability investigation revealed that refrigerator temperature is most suitable for the storage of niosomal gel. CONCLUSION: Transdermal niosomal formulation displayed promising potential in the treatment of rheumatic diseases.

D-optimal mixture design inspired modified release tablet formulation of lamotrigine for the treatment of seizures: An in-depth characterization.

OBJECTIVE: Lamotrigine (LTG) an anticonvulsant drug with a dissociation constant (pKa: 5.7), suffers from enhanced blood plasma spike after each dose, when administered as fast release tablet. Being BCS class-II candidate and pH dependent solubility, development of release-controlled tablets of LTG is a major challenge. This investigation aims at designing the release-controlled tablet (RCT) formulation of LTG using a solid dispersion (SD) technique via addressing its solubility and release problems. MATERIAL AND METHODS: RCT of LTG was fabricated using SD blend of Eudragit RL and Eudragit RS and PVP K-30 with different polymer blend ratio (1:5 and 1:7). The optimization of RCT of LTG was performed using D-optimal mixture design with three independent variables, three response variables, and one constraint. The dissolution rate was determined and data were then fitted to different mathematical models. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) studies and tableting parameters were analyzed. RESULT: In vitro studies of predicted optimized batches (POBs) have shown that drug release over a period of 12hours was 88.05±3.4% in media I, 86.10±3.7% in media II and 85.84±4.2% in media III. An in vitro kinetic model equating R2-value for all the tested models indicated that the first order and Higuchi release kinetics model were the most appropriate. CONCLUSION: Based on the optimized formulation consisting of SD of LTG with Eudragit RL, Eudragit RS and PVP K-30, the release rate was consistently similar throughout the GI tract, regardless of the pH of the environment.

Validation of automated data abstraction for SCCM discovery VIRUS COVID-19 registry: practical EHR export pathways (VIRUS-PEEP).

Background: The gold standard for gathering data from electronic health records (EHR) has been manual data extraction; however, this requires vast resources and personnel. Automation of this process reduces resource burdens and expands research opportunities. Objective: This study aimed to determine the feasibility and reliability of automated data extraction in a large registry of adult COVID-19 patients. Materials and methods: This observational study included data from sites participating in the SCCM Discovery VIRUS COVID-19 registry. Important demographic, comorbidity, and outcome variables were chosen for manual and automated extraction for the feasibility dataset. We quantified the degree of agreement with Cohen's kappa statistics for categorical variables. The sensitivity and specificity were also assessed. Correlations for continuous variables were assessed with Pearson's correlation coefficient and Bland-Altman plots. The strength of agreement was defined as almost perfect (0.81-1.00), substantial (0.61-0.80), and moderate (0.41-0.60) based on kappa statistics. Pearson correlations were classified as trivial (0.00-0.30), low (0.30-0.50), moderate (0.50-0.70), high (0.70-0.90), and extremely high (0.90-1.00). Measurements and main results: The cohort included 652 patients from 11 sites. The agreement between manual and automated extraction for categorical variables was almost perfect in 13 (72.2%) variables (Race, Ethnicity, Sex, Coronary Artery Disease, Hypertension, Congestive Heart Failure, Asthma, Diabetes Mellitus, ICU admission rate, IMV rate, HFNC rate, ICU and Hospital Discharge Status), and substantial in five (27.8%) (COPD, CKD, Dyslipidemia/Hyperlipidemia, NIMV, and ECMO rate). The correlations were extremely high in three (42.9%) variables (age, weight, and hospital LOS) and high in four (57.1%) of the continuous variables (Height, Days to ICU admission, ICU LOS, and IMV days). The average sensitivity and specificity for the categorical data were 90.7 and 96.9%. Conclusion and relevance: Our study confirms the feasibility and validity of an automated process to gather data from the EHR.

Mapping of Palliative Care Services and Challenges in Implementation of National Program for Palliative Care in Puducherry.

Objectives: The purpose of this study was to map ongoing palliative care services and describe the characteristics of providers, recipients, level of care, and approach. Second, it seeks to investigate the difficulties encountered in implementing NPPC in the Puducherry district of UT Puducherry. This study aims to review the challenges in its implementation. Material and Methods: The study using both quantitative and qualitative design, including geospatial mapping of organisations, describing service delivery characteristics and exploring challenges faced in implementing NPPC, was conducted from July 2021 to January 2022. In-depth interviews were conducted with seven healthcare providers, four patients and three caregivers, as well as key informant interviews with six doctors in administration. Results: Thirteen organisations providing palliative care to population of Puducherry district of union territory Puducherry and neighbouring districts of Tamil Nadu were identified. Mapped organisations were primarily concentrated in urban areas. Morphine was available only at three medical colleges, providing outpatient palliative care services. Non-governmental organisations provided only home-based palliative care services and the hospices provided both in-patient and home-based services. Key barriers perceived by the health system were difficulty in procuring morphine, inadequate personnel and inadequate funding. Few barriers perceived by patients/family were stigma faced in community, psychological challenges and poor quality of care. Conclusions: Palliative care services are mainly available in urban areas and through private hospices. There is a need to implement palliative care program through the public health system to improve the accessibility in the rural areas.

Targeted delivery of panitumumab-scaffold bosutinib-encapsulated polycaprolactone nanoparticles for EGFR-overexpressed colorectal cancer.

Aims: Panitumumab (anti-Erb)-conjugated polycaprolactone (PCL) nanoparticles loaded with bosutinib (BTNB) were used to develop a targeted drug-delivery system for colon cancer cells. Materials & methods: Using carbodiimide coupling, anti-Erb was conjugated to BTNB-loaded PCL nanoparticles. Dynamic light scattering, scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, x-ray diffraction and thermogravimetric analysis were used to analyze nanoparticles. Results: According to in vitro studies, anti-Erb-BTNB-PCL nanoparticles inhibited HCT116 cells more than BTNB alone. Cell arrest at different phases was examined for apoptotic potential. An in vivo efficacy study showed that anti-Erb-BTNB-PCL nanoparticles could target tumors selectively. Conclusion: Anti-Erb-conjugated BTNB nanoparticles could specifically target colon cancer.

LIKE EARLY STARVATION 1 and EARLY STARVATION 1 promote and stabilize amylopectin phase transition in starch biosynthesis.

Starch, the most abundant carbohydrate reserve in plants, primarily consists of the branched glucan amylopectin, which forms semi-crystalline granules. Phase transition from a soluble to an insoluble form depends on amylopectin architecture, requiring a compatible distribution of glucan chain lengths and a branch-point distribution. Here, we show that two starch-bound proteins, LIKE EARLY STARVATION 1 (LESV) and EARLY STARVATION 1 (ESV1), which have unusual carbohydrate-binding surfaces, promote the phase transition of amylopectin-like glucans, both in a heterologous yeast system expressing the starch biosynthetic machinery and in Arabidopsis plants. We propose a model wherein LESV serves as a nucleating role, with its carbohydrate-binding surfaces helping align glucan double helices to promote their phase transition into semi-crystalline lamellae, which are then stabilized by ESV1. Because both proteins are widely conserved, we suggest that protein-facilitated glucan crystallization may be a general and previously unrecognized feature of starch biosynthesis.

Development and Validation of an Acute Respiratory Distress Syndrome Prediction Model in Coronavirus Disease 2019: Updated Lung Injury Prediction Score.

OBJECTIVE: To develop and validate an updated lung injury prediction score for coronavirus disease 2019 (COVID-19) (c-LIPS) tailored for predicting acute respiratory distress syndrome (ARDS) in COVID-19. PATIENTS AND METHODS: This was a registry-based cohort study using the Viral Infection and Respiratory Illness Universal Study. Hospitalized adult patients between January 2020 and January 2022 were screened. Patients who qualified for ARDS within the first day of admission were excluded. Development cohort consisted of patients enrolled from participating Mayo Clinic sites. The validation analyses were performed on remaining patients enrolled from more than 120 hospitals in 15 countries. The original lung injury prediction score (LIPS) was calculated and enhanced using reported COVID-19-specific laboratory risk factors, constituting c-LIPS. The main outcome was ARDS development and secondary outcomes included hospital mortality, invasive mechanical ventilation, and progression in WHO ordinal scale. RESULTS: The derivation cohort consisted of 3710 patients, of whom 1041 (28.1%) developed ARDS. The c-LIPS discriminated COVID-19 patients who developed ARDS with an area under the curve (AUC) of 0.79 compared with original LIPS (AUC, 0.74; P<.001) with good calibration accuracy (Hosmer-Lemeshow P=.50). Despite different characteristics of the two cohorts, the c-LIPS's performance was comparable in the validation cohort of 5426 patients (15.9% ARDS), with an AUC of 0.74; and its discriminatory performance was significantly higher than the LIPS (AUC, 0.68; P<.001). The c-LIPS's performance in predicting the requirement for invasive mechanical ventilation in derivation and validation cohorts had an AUC of 0.74 and 0.72, respectively. CONCLUSION: In this large patient sample c-LIPS was successfully tailored to predict ARDS in COVID-19 patients.

Selection of Suitable Protein Structure from Protein Data Bank: An Important Step in Structure-based Drug Design Studies.

The selection of a protein structure is an important step for the success of the drug discovery process using structure-based design. Selection of the right crystal structure is critical as multiple crystal structures are available for the same protein in the Protein Data Bank (PDB). In this communication, we have discussed a systematic approach for selecting the right type of protein structure. Selecting crystal structures of TACE, 11ß-HSD1, DprE1, and SARS-CoV-2 Mpro enzymes for some case studies have been discussed for illustration.

Morpho-functional characterization of the submucosal glands at the nasopharyngeal end of the auditory tube in humans.

BACKGROUND: The auditory tube (AT), an osteocartilaginous channel, connects the nasopharynx to the middle ear cavity. At the nasopharyngeal opening of the AT, there are dense collections of submucosal glands. In a recent article, Valstar et al. proposed these nasopharyngeal tubal glands conglomerate as salivary glands, which starkly contrasts with their previously known anatomy for being a component of the respiratory tract. This study examines the contesting views regarding the taxonomical categorization of the nasopharyngeal tubal glands. MATERIALS AND METHODS: The AT glands in context were examined in human cadavers grossly, and microscopically using routine and special (Hematoxylin and Eosin [H&E] and Periodic acid-Schiff [PAS] respectively), as well as immunohistochemical (for alpha-SMA and salivary amylase) staining methods and compared with the major and minor salivary glands and the submucosal glands in the trachea. Further, a biochemical analysis was performed to detect the presence of salivary amylase in the oral and nasopharyngeal secretions of the four living human subjects, representing major salivary glands and tubal glands, respectively. RESULTS: The submucosal seromucous glands with a surface lining of respiratory epithelium were observed at the nasopharyngeal end of AT. The cells in the tubal glands showed cytoplasmic positivity for alpha-SMA, which indicated the presence of the myoepithelial cells; however, this expression was significantly lower than in the seromucous submucosal glands within the trachea. Salivary alpha-amylase was undetectable in the cadaveric tissue samples. Moreover, the amylase level in the nasopharyngeal swabs was negligible compared to the oral swabs. CONCLUSION: The anatomical location along the respiratory tract, the presence of respiratory epithelium in the overlying mucosa, their morpho-functional resemblance to the seromucous glands in the trachea, and the absence of salivary amylase strongly indicate that the tubal glands are taxonomically different from the salivary glands. Given the available evidence, their existing recognition as a part of the respiratory tract and an integral component of the AT seems more appropriate.