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Abstract Background The severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) immune response is crucial for disease management, although diminishing immunity raises the possibility of reinfection. Methods We examined the immunological response to SARS‐CoV‐2 in a cohort of convalescent COVID‐19 patients in matched samples collected at 1 and 6−8 months after infection. The peripheral blood mononuclear cells were isolated from enrolled study participants and flow cytometry analysis was done to assess the lymphocyte subsets of naive, effector, central memory, and effector memory CD4+ or CD8+ T cells in COVID‐19 patients at 1 and 6−8 months after infection. Immunophenotypic characterization of immune cell subsets was performed on individuals who were followed longitudinally for 1 month (n = 44) and 6−8 months (n = 25) after recovery from COVID infection. Results We observed that CD4 +T cells in hospitalized SARS‐CoV‐2 patients tended to decrease, whereas CD8+ T cells steadily recovered after 1 month, while there was a sustained increase in the population of effector T cells and effector memory T cells. Furthermore, COVID‐19 patients showed persistently low B cells and a small increase in the NK cell population. Conclusion Our findings show that T cell responses were maintained at 6−8 months after infection. This opens new pathways for further research into the long‐term effects in COVID‐19 immunopathogenesis.

Mashael Algethami,1 Sanat Kulkarni,2 Maaz T Sadiq,3 Hiu KC Tang,4 Juliette Brownlie,1 Jennie N Jeyapalan,1 Nigel P Mongan,1 Emad A Rakha,1 Srinivasan Madhusudan1,4 1Nottingham Biodiscovery Institute, School of Medicine, University of Nottingham, University Park, Nottingham, NG7 3RD, UK; 2Department of Medicine, City Hospital, Sandwell and West Birmingham Hospitals NHS Trust, Birmingham, B18 7QH, UK; 3Cancer Centre, Queen Elizabeth Hospital, University Hospitals Birmingham NHS Trust, Birmingham, B15 2GW, UK; 4Department of Oncology, Nottingham University Hospitals, Nottingham, NG51PB, UKCorrespondence: Srinivasan Madhusudan, Nottingham Biodiscovery Institute, School of Medicine, University Park, University of Nottingham, Nottingham, NG7 3RD, UK, Tel +44(0)115 823 1850, Fax +44(0)115 823 1849, Email srinivasan.madhusudan@nottingham.ac.ukAbstract: Despite advances in surgery and chemotherapy, the overall outcomes for patients with advanced ovarian cancer remain poor. Although initial response rates to platinum-based chemotherapy is about 60– 80%, most patients will have recurrence and succumb to the disease. However, a DNA repair–directed precision medicine strategy has recently generated real hope in improving survival. The clinical development of PARP inhibitors has transformed lives for many patients with BRCA germline-deficient and/or platinum-sensitive epithelial ovarian cancers. Antiangiogenic agents and intraperitoneal chemotherapy approaches may also improve outcomes in patients. Moreover, evolving immunotherapeutic opportunities could also positively impact patient outcomes. Here we review the current clinical state of PARP inhibitors and other clinically viable targeted approaches in ovarian cancer.Keywords: ovarian cancer, poly-(ADP)-ribose polymerase, PARP, synthetic lethality, platinum chemotherapy

Abstract Background Approximately 7% of all reported tuberculosis (TB) cases each year are recurrent, occurring among people who have had TB in the recent or distant past. TB recurrence is particularly common in India, which has the largest TB burden worldwide. Although patients recently treated for TB are at high risk of developing TB again, evidence around effective active case finding (ACF) strategies in this population is scarce. We will conduct a hybrid type I effectiveness-implementation non-inferiority randomized trial to compare the effectiveness, cost-effectiveness, and feasibility of two ACF strategies among individuals who have completed TB treatment and their household contacts (HHCs). Methods We will enroll 1076 adults (≥ 18 years) who have completed TB treatment at a public TB unit (TU) in Pune, India, along with their HHCs (averaging two per patient, n = 2152). Participants will undergo symptom-based ACF by existing healthcare workers (HCWs) at 6-month intervals and will be randomized to either home-based ACF (HACF) or telephonic ACF (TACF). Symptomatic participants will undergo microbiologic testing through the program. Asymptomatic HHCs will be referred for TB preventive treatment (TPT) per national guidelines. The primary outcome is rate per 100 person-years of people diagnosed with new or recurrent TB by study arm, within 12 months following treatment completion. The secondary outcome is proportion of HHCs

Porkbush or Elephant bush is a popular succulent garden plant scientifically known as Portulacaria afra Jacq., is often used for bonsai through out the world. This plant is found to be effective in carbon sequestration (binding atmospheric carbon, which is responsible for climate change), in thickest and semi-arid landscape vegetation. It is also used for restoration purposes. In view of the importance of this plant, MS medium was optimized for callus induction from the leaves of the P. afra. The leaves were used as the explants for callus induction on biochemically modified MS media at different hormonal concentrations of MS+0.5 mg/L, MS+1.0 mg/L and MS+1.5 mg/L of 2,4-D and MS+0.1 mg/L, MS+0.25 mg/L and MS+0.5 mg/L of BAP and different Vitamin-Amino acid cocktail concentrations of VACT-1, VACT-2 and VACT-3 along with control media without PGR (VACT-0) and vitamin-amino acid concentrations. The optimum medium for effective callus induction from the leaves of P. afra was found to be MS+1.5 mg/L 2, 4-D, 0.5 mg/L of BAP and VACT-3 (Myo-Inositol-150 mg/L, Pyridoxine HCl-0.15 mg/L, Thiamine HCl-0.5 mg/L and Glycine-3.0 mg/L) with slight modification of micro nutrients under optimal culture conditions. Effective callus induction was seen on the modified MS medium. [ABSTRACT FROM AUTHOR]

AimsModulation of DNA base excision repair (BER) has the potential to enhance response to chemotherapy and improve outcomes in tumours such as melanoma and glioma. APE1, a critical protein in BER that processes potentially cytotoxic abasic sites (AP sites), is a promising new target in cancer. In the current study, we aimed to develop small molecule inhibitors of APE1 for cancer therapy.MethodsAn industry-standard high throughput virtual screening strategy was adopted. The Sybyl8.0 (Tripos, St Louis, MO, USA) molecular modelling software suite was used to build inhibitor templates. Similarity searching strategies were then applied using ROCS 2.3 (Open Eye Scientific, Santa Fe, NM, USA) to extract pharmacophorically related subsets of compounds from a chemically diverse database of 2.6 million compounds. The compounds in these subsets were subjected to docking against the active site of the APE1 model, using the genetic algorithm-based programme GOLD2.7 (CCDC, Cambridge, UK). Predicted ligand poses were ranked on the basis of several scoring functions. The top virtual hits with promising pharmaceutical properties underwent detailed in vitro analyses using fluorescence-based APE1 cleavage assays and counter screened using endonuclease IV cleavage assays, fluorescence quenching assays and radiolabelled oligonucleotide assays. Biochemical APE1 inhibitors were then subjected to detailed cytotoxicity analyses.ResultsSeveral specific APE1 inhibitors were isolated by this approach. The IC(50) for APE1 inhibition ranged between 30 nM and 50 μM. We demonstrated that APE1 inhibitors lead to accumulation of AP sites in genomic DNA and potentiated the cytotoxicity of alkylating agents in melanoma and glioma cell lines.ConclusionsOur study provides evidence that APE1 is an emerging drug target and could have therapeutic application in patients with melanoma and glioma.

Endophytes are a group of endosymbiotic microorganisms, which colonizes the plants and they can be readily isolated in the laboratory on a specific microbial medium. These endophytes are known to be the reservoirs of many novels, secondary metabolites. Endophytic microorganisms, especially bacteria are known to colonize many plants, including medicinal plants. Apart from synthesizing the secondary metabolites in the associated plants, the endophytic microorganisms are known to increase the ability of synthesizing the bioactive components. In the current study, we investigated on analyzing these endophytic microorganisms especially bacteria associated with the medicinal plant that can synthesize the secondary metabolite compounds under abiotic stress in Withania somnifera. Entophytic bacteria from rizzoplane and risosphere was isolated from the leaves and roads of W. somnifera. Pure bacterial isolates were identified using 16S rRNA sequencing. 16S rRNA sequences showed that the bacterial isolates were found to be in close resemblance with Bacillus velezensis, Bacillus amyloliquefaciens and Pseudomonas floridensis. Further, the pure culture cell free extracts with Withanolides and sterols substrates were extracted and analyzed using HPLC and TLC. Out of the total bacterial cultures isolated, B9 and B6 isolates showed significant bands when compared with control. Similarly, B1 isolates showed unique bands when compared with control. The rise in the production of the secondary metabolite components such as withaferin A, withanolide D was significant as seen when treated with bacterial endophytes than the control. The findings of the current research can be used in tracing the application of potent bacterial endophytes in modifying the natural chemical structure of the secondary metabolite compounds. [ABSTRACT FROM AUTHOR]

Rachel Abbotts, Nicola Thompson, Srinivasan Madhusudan University of Nottingham, Academic Unit of Oncology, Division of Oncology, School of Medicine, Nottingham University Hospitals, City Hospital Campus, Nottingham, UK Abstract: Genomic deoxyribonucleic acid (DNA) is under constant threat from endogenous and exogenous DNA damaging agents. Mammalian cells have evolved highly conserved DNA repair machinery to process DNA damage and maintain genomic integrity. Impaired DNA repair is a major driver for carcinogenesis and could promote aggressive cancer biology. Interestingly, in established tumors, DNA repair activity is required to counteract oxidative DNA damage that is prevalent in the tumor microenvironment. Emerging clinical data provide compelling evidence that overexpression of DNA repair factors may have prognostic and predictive significance in patients. More recently, DNA repair inhibition has emerged as a promising target for anticancer therapy. Synthetic lethality exploits intergene relationships where the loss of function of either of two related genes is nonlethal, but loss of both causes cell death. Exploiting this approach by targeting DNA repair has emerged as a promising strategy for personalized cancer therapy. In the current review, we focus on recent advances with a particular focus on synthetic lethality targeting in cancer. Keywords: biomarker, drug target, synthetic lethality

They jjQ and bglJ genes encode LuxR-type transcription factors conserved in several enterobacterial species. YjjQ is a potential virulence factor in avian pathogenic Escherichia coli. BglJ counteracts the silencing of the bgl ([beta]-glucoside) operon by H-NS in E. coli K-12. Here we show that yjjQ and bglJ forman operon carried by E. coli K-12, whose expression is repressed by the histone-like nucleoid structuring (H-NS) protein. The LysR-type transcription factor LeuO counteracts this repression. Furthermore, the yjjP gene, encoding a membrane protein of unknown function and Iocated upstream in divergent orientation to the yjjQ-bglJ operon, is likewise repressed by H-NS. Mapping of the promoters as well as the H-NS and LeuO binding sites within the 555-bp intergenic region revealed that H-NS binds to the center of the AT-rich regulatory region and distal to the divergent promoters. LeuO sites map to the center and to positions distal to the yjjQ promoters, while one LeuO binding site overlaps with the divergent yjjP promoter. This latter LeuO site is required for full derepression of the yjjQ promoters. The arrangement of regulatory sites suggests that LeuO restructures the nucleoprotein complex formed by H-NS. Furthermore, the data support the conclusion that LeuO, whose expression is likewise repressed by H-NS and which is a virulence factor in Salmonella enterica, is a master regulator that among other loci, also controls the yjjQ-bglJ operon and thus indirectly the presumptive targets of YjjQ and BglJ.

Simple bone cysts (SBC) are pseudocysts occurring less commonly in the maxillofacial region. The uncertain and unclear etiopathogenesis led to numerous synonyms to refer this particular cyst. These cysts are devoid of an epithelial lining and are usually empty or contain blood or straw-colored fluid. In jaws initially it mimics a periapical cyst and later can lead to cortical bone expansion warranting for radical approach, which is seldom required. SBC is predominantly diagnosed in first two decades of life. Here we report a case of solitary bone cyst mimicking a periapical cyst of a mandibular molar in a 37-year-old patient.

An awareness and understanding of the presence of an additional root and unusual root canal morphology is essential as it determines the successful outcome of endodontic treatment. A thorough knowledge of basic root canal anatomy and its variation is necessary for successful completion of endodontic treatment. This report points to the importance of looking for additional roots and canals with the help of operating microscope. Finding additional roots and canals would enable clinician to successfully treat a case that would otherwise not be successful.

Silencing of the Escherichia coli bgl operon by the histone-like nucleoid-structuring protein H-NS occurs at two levels. Binding of H-NS upstream of the promoter represses transcription initiation, whilst binding within the coding region is also proposed to repress transcription elongation. The latter, downstream level of repression is counteracted by the protease Lon and, thus, silencing of the bgl operon is more effective in Ion mutants. Transposon-mutagenesis screens for suppression of this/on phenotype on bgl were performed and insertion mutations disrupting rpoS and cr/were obtained, as well as mutations mapping upstream of the open reading frames of bgU, leuO and dnaK. In rpoS and cr/mutants, bgl promoter activity is known to be higher. Likewise, as shown here, bgl promoter activity is increased in the bgU and leuO mutants, which express BglJ and LeuO constitutively. However, BglJ and LeuO have no impact on downstream repression. A dnaKJ mutant was isolated for the first time in the context of the bgl operon. The mutant expresses lower levels of DnaK than the wild-type. Interestingly, in this dnaKJ:: miniTn 10 mutant, downstream repression of bgl by H-NS is less effective, whilst upstream repression by H-NS remains unaffected. Together, the data show that the two levels of bgl silencing by H-NS are regulated independently.