Crystal structure of a newly identified M61 family aminopeptidase with broad substrate specificity that is solely responsible for recycling acidic amino acids.

Aminopeptidases with varied substrate specificities are involved in different crucial physiological processes of cellular homeostasis. They also have wide applications in food and pharma industries. Within the bacterial cell, broad specificity aminopeptidases primarily participate in the recycling of amino acids by degrading oligopeptides generated via primary proteolysis mediated by cellular ATP-dependent proteases. However, in bacteria, a truly broad specificity enzyme, which can cleave off acidic, basic, Gly and hydrophobic amino acid residues, is extremely rare. Here, we report structure-function of a putative glycyl aminopeptidase (M61xc) from Xanthomonas campestris pv campestris (Xcc) belonging to the M61 peptidase family. The enzyme exhibits broad specificity and cleaves Ala, Leu, Asp, Glu, Met, Ser, Phe, Tyr, Gly, Arg, and Lys at the N terminus, optimally of peptides with a length of 3-7 amino acids. Further, we report the high-resolution crystal structure of M61xc in the apo form (2.1 Å) and bestatin-bound form (1.95 Å), detailing its catalytic and substrate preference mechanisms. Comparative analysis of enzyme activity in crude cell extracts from both wild-type and m61xc-knockout mutant strains of Xcc has elucidated the unique intracellular role of M61xc. This study suggests that M61xc is the exclusive enzyme in these bacteria that is responsible for liberating Asp/Glu residues from the N-termini of peptides. Also, in view of its broad specificity and peptide degradation ability, it could be considered equivalent to M1 or other oligomeric peptidases from families like M17, M18, M42 or S9, who have an important auxiliary role in post-proteasomal protein degradation in prokaryotes.

Characterization of a secreted aminopeptidase of M28 family from B. fragilis and its possible role in protein metabolism in the gut.

Products of microbial protein metabolism in the gut can influence the health of the host in many ways. Members of the Bacteriodales, major commensals of the human colon have been associated with long-term intake of high-protein diets. Undigested proteins or peptides that reach the colon can be hydrolyzed by extra-cellular proteases found in some Bacteroides species into amino acids and peptides which can be further catabolized. In this communication, we have characterized one such secreted aminopeptidase (BfAP) from Bacteroides fragilis belonging to the M28 family which is capable of degrading peptides released from soybean protein after predigestion in the small intestine. The BfAP enzyme was cloned, expressed in E. coli, and purified to homogeneity. It is a metallopeptidase requiring Co2+ ion for optimum activity at 55 °C and pH 8 and preferentially cleaves neutral aliphatic (Met/Leu) and positively charged (Arg/Lys) amino acids from the N-terminus of peptides. It showed high specificity for long peptides as well as proteins like ß-casein. Structural analysis of BfAP and its orthologues using AlphaFold2 reveal a shared highly conserved M28 domain, but vary with respect to their N-terminal region with some of them possessing an additional cap domain which may be important for regulation of substrate binding. Although BfAP lacks the typical cap domain, it shows small extensions that can form a loop adjacent to the proposed active site and may affect substrate binding. We suggest that this secreted enzyme may play an important role in protein metabolism in the colon where Bacteroides species are abundant.

Insights into microRNA-mediated interaction and regulation of metabolites in tomato.

microRNAs direct regulation of various metabolic pathways in plants and animals. miRNAs may be useful in developing novel/elite genotypes, with enhanced metabolites and disease resistance. We examined miRNAs in tomato. In tomato, miRNAs in the carotenoid pathway have not been fully elucidated. We examined the potential role of miRNAs in biosynthesis of carotenoids, transcript profiling of miRNAs and their possible targets (genes and transcription factors) at different development stages of tomato using stem-loop PCR and RT-qPCR. We also identified miRNAs targeting key flavonoid genes, such as chalcone isomerase (CHI), and dihydroflavonol-4-reductase (DFR). Distinct expression profiles of miRNAs and their targets were found in fruits of three tomato accessions, suggesting carotenoid regulation by miRNAs at various stages of fruit development. This was also confirmed using HPLC of the carotenoids. The present study may help in understanding possible regulation of carotenoid biosynthesis. The identified miRNAs can be exploited to enhance biosynthesis of different carotenoids in plants.

Prognostic Significance of Serum Biochemistry Profile in Children With Severe Acute Malnutrition.

Background Malnutrition is a condition caused by defective nutrition in which either deficiency or excess of energy, protein, or micronutrients cause any measurable adverse effects on tissues/body form (body shape, size, composition), function, and clinical outcome. Children with a weight-for-height below -3 standard deviations (SD) of the mean based on the WHO standards have a high risk of death exceeding nine-fold that of children with a weight-for-height above 1 SD. In severe acute malnutrition (SAM) liver function tests, renal function tests, and serum electrolytes are deranged but their correlation with the prognosis is not well defined. So, there was a need for a study to know the prognostic significance. For this purpose, the current study was conducted in the pediatric ward of Uttar Pradesh University of Medical Sciences (UPUMS), Saifai, UP, India. Method This is an observational cross-sectional study conducted in the Department of Pediatrics, UPUMS (Saifai, UP, India) from January 2018 to July 2019 after approval from the institutional ethical committee. We enrolled 100 children with SAM who fulfilled the inclusion criterion after obtaining proper and well-informed consent. Result We studied children aged six to 59 months. The mean age of admitted patients in our study was nearly 24 months (24.18 months). The median age that was most common at the time of admission is nearly 1 year (13 months). In our study relation of serum sodium and serum potassium with the survival of SAM was found statistically significant. Conclusion Severe acute malnutrition is both a medical and social disorder. The risk of mortality increases as the severity of malnutrition increases. High-risk cases can be identified and can be treated aggressively and on a priority basis. Serum electrolyte disturbances in SAM are one of the most important predictors of the severity.

A Digitally Capable Mobile Health Clinic to Improve Rural Health Care in America: A Pilot Quality Improvement Study.

Objective: To address the problem of limited health care access for patients in rural southern Minnesota, a digitally capable mobile health clinic (MHC) quality improvement initiative was launched in a rural community-based health system. Methods: This project was designed and implemented according to our institutional strategic plan, guiding principles for virtual community care, and existing approved standards of care. A quality improvement development and pilot implementation framework was rapidly developed using Agile methodology. Results: The resulting technology and equipment selection, overall clinic design, vehicle vendor selection, clinical schedule and workflows, staffing model, equipment and technology selection, and testing were achieved in 12 months. The pilot site communities were chosen on the basis of size, interest, and lack of existing access. Four underserved rural communities now have access to telehealth consultations, laboratory testing, and in-person primary care examinations. By April 30, 2022, the MHC had provided 1498 patient appointments while maintaining our standards of care. Newly established broadband internet access for these communities and their residents was a valuable secondary outcome. Conclusion: By designing and implementing an MHC quality improvement intervention that provides both in-person and advanced telehealth options for patients in rural communities, our institution rapidly provided a potential solution for the rural health care crisis. The MHC not only replaces traditional brick-and-mortar facilities but also expands service offerings and access to technology for rural communities and the people who live and work in them.

Learning gain in web (internet) sourced seminars versus textbook sourced seminars in postgraduate medical students.

BACKGROUND: In the past, textbook or printed material was the only source of information for medical students or post-graduate students. After the introduction of internet, knowledge can be accessed easily which is updated with various aids such as animation, videos which improve the learning efficiency. This study was conducted to compare the learning efficiency between textbook-based seminar to that of internet-based seminar in postgraduate students of the department of dermatology. MATERIALS AND METHODS: It was a non-randamized controlled study. The postgraduate students in the department of dermatology, Jawaharlal Nehru Medical college, DMIMS(DU),Sawangi (Meghe), Wardha, Maharashtra, India were divided into two equal groups by simple randomization method by flipping the coin. Totally 20 seminar topics were divided into two groups (A and B) consisting of 10 seminars in each group. Postgraduate students assigned in group A were asked to prepare seminar solely from textbooks while in group B, students were asked to prepare seminar by referring internet. Feedback form which consists of 7 points, i.e. appearance, completeness of preparation, clarity of presentation, appropriate use of audio visual aids, understanding of subject, ability to answer questions, and overall performance were filled up from faculties and postgraduate students after completion of each seminar. Pretest and post-test were filled up from postgraduate students before and after each seminar respectively. Learning gain was calculated by comparing the scores of pretest and posttest. Paired t-test was used to compare results in the group and unpaired t-test was used to compare results between the two groups. RESULTS: Faculties' feedback on overall performance was higher (4.59 ± 0.15) in web-based seminars as compared to in textbook-based seminars (3.85 ± 0.1) with significant P = 0.008. Furthermore, postgraduate students' feedback showed statistical significant value of 0.02 in web-based seminars (4.65 ± 0.06) compared to textbook-based seminars (3.2 ± 0.06). Learning gain was significantly higher in web-based seminar compared to textbook-based seminar with P = 0.02. CONCLUSION: It can be concluded that web-based learning can improve the learning efficiency in postgraduate medical students.

A case of cervical OPLL and DISH mimicking stroke.

Background: Ossification of the posterior longitudinal ligament (OPLL) is a progressive disorder that mostly involves the cervical spine. It is more prevalent in East Asian countries. Patients typically present with the gradual onset of myelopathy, while about 5% show rapid progression. Case Description: A 51-year-old diabetic and hypertensive male presented with a left-sided hemiparesis following trivial trauma. The first diagnosis was a stroke, but the subsequent workup proved negative. Subsequently, the MRI and CT studies demonstrated significant cord compression due to OPLL extending from C2 to C7. There was also a heterogeneous hyperintense intramedullary cord signal indicative of edema/myelomalacia in the retro- odontoid region. The CT also diagnosed C2-C7 diffuse idiopathic skeletal hyperostosis. Conclusion: Patients with cervical myelopathy due to OPLL rarely present about 5% of the time with the acute onset of neurological deficit following minor trauma. Certainly, one must consider high cervical OPLL as responsible for hemiparesis in a patient whose brain MR has ruled out a stroke.

BNT162b2 COVID-19 Vaccine Induced Immune Thrombocytopenic Purpura.

Immune thrombocytopenic purpura (ITP) has been reported following vaccinations such as MMR as well as after viral infections such as hepatitis C and HIV. Few case reports have been reported of ITP after COVID-19 infections and COVID-19 vaccines. Herein, we present a patient who presented with severe ITP with a platelet count of 0 after receiving the second dose of the BNT162b2 mRNA COVID-19 vaccine (also known as the Pfizer BioNTech). She subsequently recovered with a prolonged treatment course.

Layered supramolecular hydrogels from thioglycosides.

Low molecular weight hydrogels are made of small molecules that aggregate via noncovalent interactions. Here, comprehensive characterization of the physical and chemical properties of hydrogels made from thioglycolipids of the disaccharides lactose and cellobiose with simple alkyl chains is reported. While thiolactoside hydrogels are robust, thiocellobioside gels are metastable, precipitating over time into fibrous crystals that can be entangled to create pseudo-hydrogels. Rheology confirms the viscoelastic solid nature of these hydrogels with storage moduli ranging from 10-600 kPa. Additionally, thiolactoside hydrogels are thixotropic which is a desirable property for many potential applications. Freeze-fracture electron microscopy of xerogels shows layers of stacked sheets that are entangled into networks. These structures are unique compared to the fibers or ribbons typically reported for hydrogels. Differential scanning calorimetry provides gel-to-liquid phase transition temperatures ranging from 30 to 80 °C. Prodan fluorescence spectroscopy allows assignment of phase transitions in the gels and other lyotropic phases of high concentration samples. Phase diagrams are estimated for all hydrogels at 1-10 wt% from 5 to ≥ 80 °C. These hydrogels represent a series of interesting materials with unique properties that make them attractive for numerous potential applications.

Distribution of Cutaneous Malignancies in Eastern Rajasthan: A Five-Year Study.

Background: Cutaneous malignancies are rare with respect to other malignancies. The distribution of various histologies of these malignancies is not uniform. We aimed to study the distribution of these malignancies and their epidemiological pattern in Eastern Rajasthan with the data collected from various pathology labs in Jaipur. Methods: In this retrospective chart review we analysed the data of 453 patients presenting with histopathologically proven cutaneous malignancies to four major pathology departments and labs in Jaipur, Rajasthan. We recorded the distribution of these histologies according to incidence, age of presentation, gender and site predilection. The data was subsequently analysed using statistical methods. Results: Squamous cell carcinoma (36%)was the most common histology which was closely followed by basal cell carcinoma(31%). Malignant melanoma (13%) was the third most common histology to present. Other less common histologies to present were dermatofibrosarcoma, Kaposi sarcoma, non hidgkin lymphoma etc. The age range varied from 14 to 90 years. The mean age of presentation was 54.3 years. Male had a slight preponderance (1.36 times more than females)overall. Except Bcc, which had a female preponderance. Head and neck(38.41%) was the most common site to be affected overall followed by lower limbs(31.56%). Interpretation: The idea of distribution of these rare malignancies in our part of the country will not only help us in proper surgical management but also in educating the public about the possible causes and the need for early intervention leading to better prognosis.

Endovascular Treatment of Acquired Atheromatous Postsubclavian Aortic Coarctation.

Coral reef aorta is a rare calcifying obstructive disease that involves the thoracoabdominal aorta. Similar presentations in the postsubclavian aorta may result in acquired atheromatous aortic coarctation leading to systemic hypertension and heart failure. The associated calcification makes surgical anatomic or extraanatomic bypass and thromboendarterectomy challenging. Extensive circumferential calcification often precludes endovascular intervention. We present the case of a 25-year-old man with an acquired atheromatous coarctation of the postsubclavian aorta who underwent successful endovascular treatment with use of a balloon-expandable covered stent.

Functional and Radiological Outcomes Following Calcaneo-Cuboid-Cuneiform Osteotomy for the Treatment of Planovalgus Feet: A Short-Term Analysis.

INTRODUCTION: Flexible flatfoot refers to the loss of the medial longitudinal arch of the foot on weight bearing and is associated with excessive heel eversion or forefoot abduction. Unless symptomatic, flexible flatfeet are best managed non-operatively. The calcaneo-cuboid-cuneiform osteotomy is a procedure that restores the anatomical shape of the foot without arthrodesis of the joints. Our study aims to evaluate the functional and radiological outcomes of patients treated with calcaneo-cuboid-cuneiform osteotomy in patients with planovalgus feet. METHODOLOGY: A retrospective review of records and radiographs of patients with symptomatic flexible planovalgus feet, who were operated with the calcaneo-cuboid-cuneiform osteotomy by a single senior surgeon in a time period between April 2016 and July 2017 was done. The clinical and radiological outcomes were evaluated in 12 feet in 8 children. RESULTS: A total of 12 feet in 8 children were operated (6 males and 2 females). Average age of patients was 11 ± 1.27 years; average follow up was 14.7 months ± 2.7 months. Two patients had planovalgus feet secondary to spastic diplegia and 6 had idiopathic planovalgus feet. There was a statistically significant improvement in the pain score as well as the radiographic parameters in all the operated patients. CONCLUSION: The calcaneo-cuboid-cuneiform osteotomy has potential to give good results for symptomatic planovalgus feet with minimal complications.

A massive rock and ice avalanche caused the 2021 disaster at Chamoli, Indian Himalaya.

On 7 February 2021, a catastrophic mass flow descended the Ronti Gad, Rishiganga, and Dhauliganga valleys in Chamoli, Uttarakhand, India, causing widespread devastation and severely damaging two hydropower projects. More than 200 people were killed or are missing. Our analysis of satellite imagery, seismic records, numerical model results, and eyewitness videos reveals that ~27 × 106 cubic meters of rock and glacier ice collapsed from the steep north face of Ronti Peak. The rock and ice avalanche rapidly transformed into an extraordinarily large and mobile debris flow that transported boulders greater than 20 meters in diameter and scoured the valley walls up to 220 meters above the valley floor. The intersection of the hazard cascade with downvalley infrastructure resulted in a disaster, which highlights key questions about adequate monitoring and sustainable development in the Himalaya as well as other remote, high-mountain environments.

Cobra-head and other shape-memory abnormalities of nitinol atrial septal occluders: incidence, predisposing factors, and outcomes.

BACKGROUND: Shape-memory abnormalities are seen in some nitinol atrial septal occluders. Variably described as cobra-head, tulip, and others, their incidence, mechanisms, clinical impact, and outcome have not been systematically analysed. METHODS: We retrospectively reviewed all consecutive device closures in the last 6 years for deformations. Type and size of the occluder, deployment technique, size, and angulation/kinking of the delivery sheath were analysed. Procedural success, duration, and other complications were studied. RESULTS: A total of 112 devices (11.8%) among 950 occluders used in 936 patients showed deformities. Fourteen of 936 received 2 devices. Deformities were transient and self-correcting in 40%. Multivariate analysis showed significant associations with oversized sheaths (p = 0.004), kinked/angulated sheaths (p < 0.001), special deployment techniques (p < 0.001), and twist in the device waist (p = 0.011). Despite more frequent deformities with Figulla (15.6%) and Amplatzer (13.9%) occluders than Cera occluders (6.6%) and larger devices (>24 mm - 14.6%) than smaller devices (less than or equal to 24 mm - 9.7%), they were not significant on multivariate analysis. In vivo manipulations corrected most deformities; nineteen needed in vitro reformations and four needed a change of device. Despite prolongation of the procedure, repeated attempts (mean 2.76 ± 1.7 attempts, with a range from 1 to 9 attempts), and supraventricular tachycardia in two patients, there were no serious adverse effects. CONCLUSIONS: Deformations were frequent in 11.8% of atrial septal occluders on a targeted search. Oversized and angulated/kinked sheaths, special techniques like pulmonary vein deployment and twist in device waist during procedure predisposed to deformities. While most deformities were corrected with manipulations, removal of the device was infrequently needed and change of device was rarely required. Long procedural time and multiple attempts for deployment did not affect procedural success.

Chemical Additives Enable Native Mass Spectrometry Measurement of Membrane Protein Oligomeric State within Intact Nanodiscs.

Membrane proteins play critical biochemical roles but remain challenging to study. Recently, native or nondenaturing mass spectrometry (MS) has made great strides in characterizing membrane protein interactions. However, conventional native MS relies on detergent micelles, which may disrupt natural interactions. Lipoprotein nanodiscs provide a platform to present membrane proteins for native MS within a lipid bilayer environment, but previous native MS of membrane proteins in nanodiscs has been limited by the intermediate stability of nanodiscs. It is difficult to eject membrane proteins from nanodiscs for native MS but also difficult to retain intact nanodisc complexes with membrane proteins inside. Here, we employed chemical reagents that modulate the charge acquired during electrospray ionization (ESI). By modulating ESI conditions, we could either eject the membrane protein complex with few bound lipids or capture the intact membrane protein nanodisc complex-allowing measurement of the membrane protein oligomeric state within an intact lipid bilayer environment. The dramatic differences in the stability of nanodiscs under different ESI conditions opens new applications for native MS of nanodiscs.

Developmental impairments in moral competence as mitigation in capital cases.

In this article we propose a mitigation approach in those capital murder cases where traditional mitigation themes such as mental illness or low IQ are not present. To avoid prosecution characterization of these defendants as simply evil or antisocial personalities, we suggest reframing the issue as one of moral incompetence, based not on character defect but rather stemming from profoundly neglectful or abusive parenting. Under this reframing, defense teams would present evidence about the many antecedents of poor moral competence, its origins in neglect or abuse, its neurophysiological basis, and, most importantly, its potential for change. Evaluation in such cases would pay close attention to early childhood and family characteristics. We also recommend presentation of research findings showing how moral competence can be improved in adulthood, given appropriate guidance and support. This approach to mitigation is consistent with much of the developmental literature. But juror responses to these mitigation themes are as yet unknown.

New cytochalasin from Rosellinia sanctae-cruciana, an endophytic fungus of Albizia lebbeck.

AIM: To explore the potential of Rosellinia sanctae-cruciana an endophytic fungus associated with Albizia lebbeck for pharmaceutically important cytotoxic compounds. METHODS AND RESULTS: One novel cytochalasin, named jammosporin A (1) and four known analogues (2-5) were isolated from the culture of the endophytic fungus R. sanctae-cruciana, harboured from the leaves of the medicinal plant A. lebbeck. Their structures were elucidated by extensive spectroscopic analyses including one-dimensional and two-dimensional nuclear magnetic resonance data along with MS data and by comparison with literature reports. In preliminary screening the ethyl acetate extract of the fungal culture was tested for cytotoxic activity against a panel of four cancer cell lines (MOLT-4, A549, MIA PaCa-2 and MDA-MB-231), and found to be active against MOLT-4 with an IC50 value of 10 µg ml-1 . Owing to the remarkable cytotoxic activity of the extract the isolated compounds (1-5) were evaluated for their cytototoxicity against the MOLT-4 cell line by MTT assay. Interestingly, compounds 1-2, 4 and 5 showed considerable cytotoxic potential against the human leukaemia cancer cell line (MOLT-4) with IC50 values of 20·0, 10·0, 8·0 and 6·0 µmol l-1 , respectively, while compound 3 showed an IC50 value of 25 µmol l-1 . This is the first report of the existence of this class of secondary metabolites in R. sanctae-cruciana fungus. CONCLUSION: This study discovered a novel compound, named jammosporin A, isolated for the first time from R. sanctae-cruciana, an endophytic fungus of A. lebbeck with anticancer activity against the MOLT-4 cell line. SIGNIFICANCE AND IMPACT OF THE STUDY: Rosellinia sanctae-cruciana represents an interesting source of a new compound with bioactive potential as a therapeutic agent against a human leukaemia cancer cell line (MOLT-4).

Ethnopharmacology, phytochemistry, and biotechnological advances of family Apocynaceae: A review.

The family Apocynaceae is one of the largest and important families in angiosperm. Several members of this family have medicinal properties and have been in the treatment of various ailments. Most of them are consumed as food by tribal people whereas a few plants are used as source of poison. Members of family Apocynaceae are rich in alkaloids, terpenoids, steroids, flavonoids, glycosides, simple phenols, lactones, and hydrocarbons. Other compounds such as sterols, lignans, sugars, lignans, and lactones have been isolated and systematically studied. Few studies have reported antioxidant, anti-inflammatory, antimicrobial, and cytotoxic activities of crude extracts as well as single compound(s) isolated from various members of the family Apocynaceae. Holarrhena antidysenterica, Rauvolfia serpentina, Carissa carandas, and Tabernaemontana divaricata are the extensively studied plants in this family. The present review provides a detailed outlook on ethnopharmacology, phytochemistry, and biological activities of selected members of this family. Moreover, it also covers the biotechnological advances used for large-scale production of bioactive compounds of therapeutic interest along with plant tissue culture-based approaches for conservation of this medicinally valuable family.

Successful percutaneous retrieval of unusually knotted temporary pacemaker lead.

Implantation of temporary pacemaker lead is commonly performed procedure and is usually safe, but can sometimes develop rare and serious complication like intracardiac lead knotting which may require challenging retrieval techniques. We report a case of successful percutaneous retrieval of unusually knotted right internal jugular venous temporary pacing lead via left femoral transvenous approach using snare over a long sheath after cutting the electrode proximally and thus avoiding any surgical intervention.