Histone Methylation by SETD1A Protects Nascent DNA through the Nucleosome Chaperone Activity of FANCD2.

Components of the Fanconi anemia and homologous recombination pathways play a vital role in protecting newly replicated DNA from uncontrolled nucleolytic degradation, safeguarding genome stability. Here we report that histone methylation by the lysine methyltransferase SETD1A is crucial for protecting stalled replication forks from deleterious resection. Depletion of SETD1A sensitizes cells to replication stress and leads to uncontrolled DNA2-dependent resection of damaged replication forks. The ability of SETD1A to prevent degradation of these structures is mediated by its ability to catalyze methylation on Lys4 of histone H3 (H3K4) at replication forks, which enhances FANCD2-dependent histone chaperone activity. Suppressing H3K4 methylation or expression of a chaperone-defective FANCD2 mutant leads to loss of RAD51 nucleofilament stability and severe nucleolytic degradation of replication forks. Our work identifies epigenetic modification and histone mobility as critical regulatory mechanisms in maintaining genome stability by restraining nucleases from irreparably damaging stalled replication forks.

Comparative analysis of the effects of chemically and biologically synthesized silver nanoparticles on biomass accumulation and secondary metabolism in callus cultures of Fagonia indica.

Biotechnological strategies are needed to produce larger quantities of biomass and phytochemicals. In this study, callus cultures of Fagonia indica were elicited with different concentrations of chemically and biologically synthesized silver nanoparticles (chem- and bioAgNPs) to compare their effects on biomass, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of the extracts from callus. The results revealed that bioAgNPs being more biocompatible produced the highest biomass initially on day 10 (FW = 4.2152 ± 0.13 g; DW = 0.18527 ± 0.01 g) and day 20 (FW = 7.6558 ± 0.10 g; DW = 0.3489 ± 0.01 g) when supplemented in media as 62.5 µg/mL and 250 µg/mL, respectively. Initially, the highest TPC (319.32 ± 8.28 µg GAE/g of DW) was recorded on day 20 in chemAgNPs (31.25 µg/mL) induced callus as compared to TPC = 302.85 ± 3.002 µg GAE/g of DW in bioAgNPs-induced callus. Compared to the highest values of TFC (108.15 ± 2.10 µg QE/g of DW) produced in 15.6 µg/mL chemAgNPs-induced callus on day 20, TFC produced in bioAgNPs (62.5 µg/mL) was 168.61 ± 3.17 µg GAE/g of DW on day 10. Similarly, chemAgNPs-induced callus (62.5 µg/mL) showed the highest free radical scavenging activity (FRSA) i.e. 87.18% on day 20 while bioAgNPs (125 µg/mL) showed 81.69% FRSA on day 20 compared to highest among control callus (63.98% on day 40). The highest total antioxidant capacity of chemAgNPs-(125 µg/mL) induced callus was 330.42 ± 13.65 µg AAE/g of DW on day 20 compared to bioAgNPs-(62.5 µg/mL) induced callus (312.96 ± 1.73 µg AAE/g of DW) on day 10. Conclusively, bioAgNPs are potent elicitors of callus cultures of F. indica.

Neuroprotective Actions of Clinoptilolite and Ethylenediaminetetraacetic Acid Against Lead-induced Toxicity in Mice Mus musculus.

OBJECTIVES: Oxidative stress is considered as a possible molecular mechanism involved in lead (Pb(2+)) neurotoxicity. Very few studies have been investigated on the occurrence of oxidative stress in developing animals due to Pb(2+) exposure. Considering the vulnerability of the developing brain to Pb(2+), this study was carried out to investigate the effects of Pb(2+) exposure in brain regions especially on antioxidant enzyme activities along with ameliorative effects of ethylenediaminetetraacetic acid (EDTA) and clinoptilolite. METHODS: Three-week old developing Swiss mice Mus musculus were intraperitoneally administered with Pb(2+) acetate in water (w/v) (100 mg/kg body weight/day) for 21 days and control group was given distilled water. Further Pb(2+)-toxicated mice were made into two subgroups and separately supplemented with EDTA and clinoptilolite (100 mg/kg body weight) for 2 weeks. RESULTS: In Pb(2+)-exposed mice, in addition to increased lipid peroxidation, the activity levels of catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH) found to decrease in all regions of brain indicating, existence of severe oxidative stress due to decreased antioxidant function. Treatment of Pb(2+)-exposed mice with EDTA and clinoptilolite lowered the lipid peroxidation (LPO) levels revealing their antioxidant potential to prevent oxidative stress. Similarly their administration led to recover the level of catalase, SOD, and GPx enzymes affected during Pb(2+) toxicity in different regions of brain. CONCLUSIONS: The protection of brain tissue against Pb(2+)-induced toxicity by clinoptilolite and EDTA in the present experiment might be due to their ability to react faster with peroxyl radicals there by reducing the severity of biochemical variable indicative of oxidative damage. Thus, the results of present study indicate the neuroprotective potential of clinoptilolite and EDTA against Pb(2+) toxicity.

On your marks, get SET(D1A): the race to protect stalled replication forks.

We recently identified that methylation of lysine 4 of histone H3 (H3K4) by SETD1A (SET domain containing 1A) maintains genome stability by protecting newly-replicated DNA from degradation. Mechanistically, SETD1A-dependent histone methylation regulates nucleosome mobilisation by FANCD2 (FA complementation group D2), a crucial step in maintaining genome integrity with important implications in chemo-sensitivity.

Occurrence of Anxiety and Depression among Stable COPD Patients and its Impact on Functional Capability.

INTRODUCTION: Anxiety and depression are important but often under-diagnosed co-morbid conditions in patients with Chronic Obstructive Pulmonary Disease (COPD) which may affect the functional capacity of the patients. AIM: To find out the proportion of depression and anxiety among stable COPD patients using a validated questionnaire suitable for use in clinic and the factors affecting their reduced functional capability as assessed by six-minute walk test. MATERIALS AND METHODS: This was a descriptive cross-sectional study. Seventy five patients diagnosed with stable COPD in outpatient Department of Pulmonary Medicine in a tertiary care hospital, satisfying all inclusion criteria, were included in the study. They were examined clinically, categorized as per Global Initiative for Chronic Obstructive Lung Disease (GOLD) severity assessment guideline and interviewed by designated interviewer using validated questionnaire for depression (Hamilton depression rating scale, HAM-D) and anxiety (State Trait Anxiety Inventory, STAI). The functional exercise capacity of the patient was assessed by six-minute walk test. Statistical analysis was performed using Minitab software (version16.1). RESULTS: Among 75 stable COPD patients (68 male, 7 female), majority (32 out of 75) had both depression and anxiety, while only anxiety or depression was present in 9 each. The patients with depression had no significant difference in six-minute walk distance, change in heart rate and respiratory rate (p = 0.4186, 0.219 and 0.41 respectively) as compared to those without depression, but were found to be more dyspnoeic at the end of the test (p= 0.003). There was also no significant difference in walk distance in patients with high STAI score as compared to those with low STAI score (p= 0.276). CONCLUSION: Both anxiety and depression were present in majority of the stable COPD patients. The presence of these co-morbid conditions had no significant effect on the functional status of the patients in the form of reduced six-minute walk distance, though they were more symptomatic than those without these co-morbidities.

Quantitative Phosphoproteomics Reveals a Role for Collapsin Response Mediator Protein 2 in PDGF-Induced Cell Migration.

The Platelet Derived Growth Factor (PDGF) family of ligands have well established functions in the induction of cell proliferation and migration during development, tissue homeostasis and interactions between tumours and stroma. However, the mechanisms by which these actions are executed are incompletely understood. Here we report a differential phosphoproteomics study, using a SILAC approach, of PDGF-stimulated mouse embryonic fibroblasts (MEFs). 116 phospho-sites were identified as up-regulated and 45 down-regulated in response to PDGF stimulation. These encompass proteins involved in cell adhesion, cytoskeleton regulation and vesicle-mediated transport, significantly expanding the range of proteins implicated in PDGF signalling pathways. Included in the down-regulated class was the microtubule bundling protein Collapsin Response Mediator Protein 2 (CRMP2). In response to stimulation with PDGF, CRMP2 was dephosphorylated on Thr514, an event known to increase CRMP2 activity. This was reversed in the presence of micromolar concentrations of the protein phosphatase inhibitor okadaic acid, implicating PDGF-induced activation of protein phosphatase 1 (PP1) in CRMP2 regulation. Depletion of CRMP2 resulted in impairment of PDGF-mediated cell migration in an in vitro wound healing assay. These results show that CRMP2 is required for PDGF-directed cell migration in vitro.

A rare pleural effusion in a young male.

A 28-year-old male presented with fever with right-sided chest pain for 2 weeks. Clinicoradiological picture was suggestive of right-sided pleural effusion. He had history of polytrauma following a road traffic accident and had to undergo emergency laparotomy a month ago. Microscopic and culture examination of the pleural fluid showed neutrophilia, high bilirubin content and presence of gram-negative bacilli. Ultrasound of the abdomen showed the presence of biloma in the liver and right subdiaphragmatic space with fistulous communication into the right thoracic cavity. The patient was managed successfully with complete recovery.

Unilateral variations in upper limb arterial system: a case report with literature review.

In a female cadaver unilateral variations were found in upper limb arterial system - as (1) high-up origin of ulnar artery at arm, (2) persistent prominent arteria nervii mediana or median artery, (3) common interosseous artery branching out of brachial artery. Literature review revealed these coexistent anomalies as the consequence of aberrant finalization of the path chosen by axis arterial network in embryonic life.

A Rare Presentation of Os Odontoideum with Multiple Vertebral Fusion in Type III Klippel-Feil Syndrome (KFS) - A Case Report.

An abnormal atlas and axis with presence of os odontoideum and fusion of multiple vertebrae were noted in an intact skeleton, in the osteology museum of the Department of Anatomy of North Bengal Medical College, West Bengal, India.These multiple abnormalities at various levels along with increased thickness of antero-posterior arch of atlas pointed towards the congenital nature of the anomalies, possibly due to Klippel-Feil syndrome (KFS). These unusual findings denote a developmental background of the manifestations.The cervical instability, resultant neurodeficit and impairment of quality of life of the affected individuals, which are inherent in such cases, reveal their clinical importance.

Granulomatosis with polyangitis with mononeuritis multiplex-immunosuppressives playing a double-edged sword.

A 52-year-old female was diagnosed with rheumatoid arthritis and was on methotrexate and prednisolone. She developed fever, cough, hemoptysis, and cavitary lesion on chest skiagram. She was put on antitubercular therapy without any improvement, meanwhile she developed painful right foot drop. Clinicoradiology and C-ANCA study confirmed the diagnosis of granulomatosis with polyangitis (GPA). She was started on cyclophosphamide, corticosteroid, and co-trimoxazole. While her treatment was being continued she showed significant improvement of pulmonary manifestations. About 1 year later, there was reappearance of fever, cough, and radiological opacity with oropharyngeal candidiasis. She became very ill with disseminated intravascular coagulation (DIC)-like features. Immunological markers were negative but bronchoalveolar lavage fluid study showed growth of Aspergillus spp. The patient was promptly put on intravenous voriconazole but unfortunately she succumbed to her illness.

Evaluation of fluoride-induced oxidative stress in rat brain: a multigeneration study.

Multigenerational evaluation was made in rats on exposure to high fluoride (100 and 200 ppm) to assess neurotoxic potential of fluoride in discrete areas of the brain in terms of lipid peroxidation and the activity of antioxidant enzyme system. The rats were given fluoride through drinking water (100 and 200 ppm) and maintained subsequently for three generations. Fluoride treatment significantly increased the lipid peroxidation and decreased the activity of antioxidant enzymes viz, catalase, superoxide dismutase, glutathione peroxidase, glutathione S-transferase, and glutathione level in first-generation rats and these alterations were more pronounced in the subsequent second and third-generation rats in both the doses tested. Decreased feed and water consumption, litter size and organ (brain) somatic index, marginal drop in body growth rate and mortality were observed in all three generations. Decreased antioxidant enzyme activity and increased malondialdehyde levels found in the present study might be related to oxidative damage that occurs variably in discrete regions of the brain. Results of this study can be taken as an index of neurotoxicity in rats exposed to water fluoridation over several generations.

Fluoride toxicity and status of serum thyroid hormones, brain histopathology, and learning memory in rats: a multigenerational assessment.

High-fluoride (100 and 200 ppm) water was administered to rats orally to study the fluoride-induced changes on the thyroid hormone status, the histopathology of discrete brain regions, the acetylcholine esterase activity, and the learning and memory abilities in multigeneration rats. Significant decrease in the serum-free thyroxine (FT4) and free triiodothyronine (FT3) levels and decrease in acetylcholine esterase activity in fluoride-treated group were observed. Presence of eosinophilic Purkinje cells, degenerating neurons, decreased granular cells, and vacuolations were noted in discrete brain regions of the fluoride-treated group. In the T-maze experiments, the fluoride-treated group showed poor acquisition and retention and higher latency when compared with the control. The alterations were more profound in the third generation when compared with the first- and second-generation fluoride-treated group. Changes in the thyroid hormone levels in the present study might have imbalanced the oxidant/antioxidant system, which further led to a reduction in learning memory ability. Hence, presence of generational or cumulative effects of fluoride on the development of the offspring when it is ingested continuously through multiple generations is evident from the present study.