Reengineering of cancer cell surface charges can modulate cell migration

The ability to modulate the cell surface structure provides a powerful tool to understand fundamental processes and also to elicit desired cellular responses. Here we report the development of a new class of ‘clickable labels’ to reengineer the cell surface charges of live cells. The method relies on the use of metabolic oligosaccharide engineering (MOE) combined with chemo selective labeling of cell surface azido-containing sialic acids with dibenzocyclooctyne (DBCO) ionic-probes. Using this strategy, we demonstrate that reducing the negative charge induced by the overexpression of cell surface sialic acids in cancer cells leads to a reduction in cell migration without affecting drug supceptibility.

Reducing the negative charges induced by the overexpression of cell surface sialic acids using cationic clickable labels leads to a reduction in cancer cell migration without affecting drug supceptibility.

Carbon dot-based fluorescent antibody nanoprobes as brain tumour glioblastoma diagnostics

The development of efficient and sensitive tools for the detection of brain cancer in patients is of the utmost importance particularly because many of these tumours go undiagnosed until the disease has advanced and when treatment is less effective. Current strategies employ antibodies (Abs) to detect Glial Fibrillary Acid Protein (GFAP) in tissue samples, since GFAP is unique to the brain and not present in normal peripheral blood, and it relies on fluorescent reporters. Herein we describe a low cost, practical and general method for the labelling of proteins and antibodies with fluorescent carbon dots (CD) to generate diagnostic probes that are robust, photostable and applicable to the clinical setting. The two-step protocol relies on the conjugation of a dibenzocyclooctyne (DBCO)-functionalised CD with azide functionalised proteins by combining amide conjugation and strain promoted alkyne-azide cycloaddition (SPAAC) ligation chemistry. The new class of Ab-CD conjugates developed using this strategy was successfully used for the immunohistochemical staining of human brain tissues of patients with glioblastoma (GBM) validating the approach. Overall, these novel fluorescent probes offer a promising and versatile strategy in terms of costs, photostability and applicability which can be extended to other Abs and protein systems.

Correlation between Chondromalacia Patella and Patellofemoral Factors in Middle-Age Population: A Clinical, Functional, and Radiological Analysis

Background Despite higher incidence of patellofemoral pain (PFP) and consequently morbidity, the understanding about PF factors leading to PF arthritis is way lacking.

Material and Methods A prospective study of first 80 patients who were diagnosed with chondromalacia patella (CMP) on magnetic resonance imaging (MRI) divided into early and late CMP groups were evaluated clinically, radiologically, and in terms of functional outcome.

Results : Quadriceps angle, Clark’s test, and Insall–Salvati ratio results were nonsignificant despite greater values were observed in late CMP group, whereas trochlear morphology results (sulcus angle: 153:138 degrees and sulcus depth 3.9:5.4 mm) and clinical scores were significant in late CMP group (Kujala’s score: 61:78, whereas PF pain score: 43:25). Type-C patellar morphology was found in greater number in late CMP cohort.

Conclusion Trochlear and patellar morphologies along with clinical scores play a key role in understanding of the CMP.

Postoperative Epidural Fibrosis Prevention: Which Is Better-Autologous Fat versus Gelfoam

Study Design

Prospective, randomized study of 100 patients with prolapsed intervertebral disc with an average of 12- to 18-month follow-up postoperatively.

Purpose

To compare the role of Gelfoam and autologous fat in the prevention of postoperative epidural fibrosis (EF) after lumbar spine surgery.

Overview of Literature

EF is a possible sequelae of lumbar disc surgery. Different treatments and surgical strategies have been attempted to prevent postoperative fibrosis without providing consistent long-term results.

Methods

The study was conducted on 100 adult patients. The patients were randomly allocated into two groups of 50 patients each: group A, autologous fat group, and group B, Gelfoam group. The postoperative follow-up was conducted at intervals of 6 weeks, 3 months, 6 months, and 12 months. Both groups were evaluated clinically (Oswestry Low Back Pain Disability Questionnaire [ODI], Visual Analog Scale [VAS], Straight Leg Raising Test [SLRT]) and radiologically (using Ross grading by contrast magnetic resonance imaging [MRI]) for development of radicular pain and hence EF.

Results

Based on the analysis, improvement in mean values of ODI score, VAS score, and SLRT were found to be statistically significant postoperatively at intervals of 6 weeks, 3 months, 6 months, and 12 months when compared individually in both groups. However, improvement was greater in the autologous fat group than in the Gelfoam group. Based on contrast-enhanced MRI, the number of patients who developed EF was smaller in the autologous fat group than in the Gelfoam group.

Conclusions

In the present study, on clinical and radiological assessment, we conclude that both groups prevent radicular pain and postoperative EF individually but relatively autologous fat was found to be more effective than Gelfoam in the prevention of EF and hence radicular pain.

A Prospective Observational Multi-institutional Study on Invasive Fungal Infections Following Chemotherapy for Acute Myeloid Leukemia (MISFIC Study): A Real World Scenario from India

We performed a prospective multi-centre observational study to understand the incidence of IFI in patients with AML in India with use of anti-fungal prophylaxis. All patients with AML receiving either induction chemotherapy or salvage chemotherapy between November 2014 and February 2016 were included in this prospective observational study from 10 Indian centres. IFI was defined as per the revised EORTC-MSG criteria. Data on type of chemotherapy used, type of anti-fungal prophylaxis used, time to neutrophil recovery, incidence of IFI and survival were collected. Two hundred patients (118 male and 82 females) with a median age of 35 years (range: 2-66) were recruited. One hundred and eighty-six (93%) had newly diagnosed acute myeloid leukemia (AML) while 14 (7%) had relapsed disease. IFI occurred in 53 patients (26.5%) with proven or probable IFI occurring in 17 (8.5%). Use of posaconazole prophylaxis (p = 0.027) was the only factor found to be associated with a reduced incidence of IFI. The overall survival (OS) at 6 weeks and 3 months respectively was similar among patients who had IFI (83.0 ± 5.2%; 81.0 ± 5.4%) as compared to those without IFI (84.4 + 3.0%; 81.4 ± 3.2%). This prospective study reveals a high incidence of IFI in patients undergoing chemotherapy for AML in India. The use of posaconazole prophylaxis was associated with a significantly lower incidence of IFI. Optimal strategies to prevent IFI need to be studied.

NCα-gem-dimethylated peptoid side chains: A novel approach for structural control and peptide sequence mimetics

The design of linear peptoid oligomers adopting well-defined secondary structures while mimicking defined peptide primary sequences is a major challenge in the context of drug discovery. To this end, chemists have developed cis-inducing peptoid side chains to build robust polyproline type I helices. However, the number of efficient examples remains scarce and chemical diversity accessible through the use of these side chains is limited. Herein, we introduce an array of NCα-gem-dimethylated peptoid residues mimicking proteinogenic amino acids. Submonomer synthesis and block-coupling approaches were explored to access heterooligomers incorporating these novel types of side chains. NMR studies of monomer and trimer models showed that the NCα-gem-dimethylated groups exert complete cis control on the backbone amide conformation. Lastly, a preliminary molecular modeling study gave an insight into the preferred orientation of the substituents of the NCα-gem-dimethyl side chains relative to the peptoid backbone.

Role of neuropeptide Y and galanin in high altitude induced anorexia in rats

Anorexia causing weight loss at high altitude (HA) is a major problem. Neuropeptide Y (NPY) and galanin are considered to have appetite regulatory function. The present study was therefore undertaken to investigate the changes in these two peptides at simulated HA and its possible role in anorexia. Male Sprague-Dawley rats (n = 8 in each group) were exposed to simulated HA (7620 m) for 1, 7, 14 and 21 days for 6 h a day and to an altitude of 6,096 m for 72 h to study the effect of intermittent and continuous exposure, respectively. NPY and galanin levels were estimated in different brain parts and plasma of exposed and unexposed control animals. Significant reduction in food intake was observed in rats during both intermittent as well as continuous exposure. In case of 72 h continuous exposure severe reduction in food intake was observed (73.2%) with reduction in body mass (approximately 29.7g/rat in 48h). Hypothalamic NPY levels were decreased by 54.7, 35.0 and 15.4% in 1, 7, and 14 days, respectively, in case of intermittent exposure to HA. However in case of 72 h HA exposure no significant change in hypothalamic and circulating NPY levels were observed. Plasma galanin levels were decreased in both intermittent and 72 h continuous HA exposed rats. Hypothalamic galanin levels were also decreased in 72h exposed rats. The changes in levels of these peptides may be responsible for anorexia at HA.

Effect of an antidiabetic extract of Catharanthus roseus on enzymic activities in streptozotocin induced diabetic rats

Hypoglycemic activity was detected in dichloromethane:methanol extract (1:1) of leaves and twigs of Catharanthus roseus (family Apocynaceae), a traditionally used medicinal plant, using streptozotocin (STZ) induced diabetic rat model. Extract at dose 500 mg/kg given orally for 7 and 15 days showed 48.6 and 57.6% hypoglycemic activity, respectively. Prior treatment at the same dose for 30 days provided complete protection against STZ challenge (75 mg/kg/i.p.x1). Enzymic activities of glycogen synthase, glucose 6-phosphate-dehydrogenase, succinate dehydrogenase and malate dehydrogenase were decreased in liver of diabetic animals in comparison to normal and were significantly improved after treatment with extract at dose 500 mg/kg p.o. for 7 days. Results indicate increased metabolization of glucose in treated rats. Increased levels of lipid peroxidation measured as 2-thiobarbituric acid reactive substances (TBARS) indicative of oxidative stress in diabetic rats were also normalized by treatment with the extract.

Differential antioxidative responses to cadmium in roots and leaves of pea (Pisum sativum L. cv. Azad)

Pea (Pisum sativum L. cv. Azad) plants exposed to 4 and 40 microM of Cd for 7 d in hydroponic culture were analysed with reference to the distribution of metal, the accumulation of biomass and the metal's effects on antioxidants and antioxidative enzymes in roots and leaves. Cd-induced a decrease in plant biomass. The maximum accumulation of Cd occurred in roots followed by stems and leaves. An enhanced level of lipid peroxidation and an increased tissue concentration of hydrogen peroxide (H2O2) in both roots and leaves indicated that Cd caused oxidative stress in pea plants. Roots and leaves of pea plants responded differently to Cd with reference to the induction of enhanced activities of most of the enzymes monitored in the present study. These differential responses to Cd were further found to be associated with levels of Cd to which the plants were exposed. Cd-induced enhancement in superoxide dismutase (SOD) activity was more at 40 microM than at 4 microM in leaves. While catalase (CAT) prominently increased in leaves both at 4 and 40 microM Cd, ascorbate peroxidase (APX) showed maximum stimulation at 40 microM Cd in roots. Enhancement in glutathione reductase (GR) activity was also more at 40 microM than at 4 microM Cd in roots. While glutathione peroxidase (GPOX) activity decreased in roots and remained almost unmodified in leaves, glutathione S-transferase (GST) showed pronounced stimulation in both roots and leaves of pea plants exposed to 40 microM Cd. Increased activities of antioxidative enzymes in Cd-treated plants suggest that they have some additive function in the mechanism of metal tolerance in pea plants.

Diversity of the killer cell Ig-like receptors of rhesus monkeys

Because the killer cell Ig-like receptors (KIRs) have only been characterized in humans and chimpanzees, we do not have a full understanding of their evolutionary history. Therefore, cDNAs encoding the KIR molecules of five rhesus monkeys were characterized, and were found to differ from the KIR molecules identified in humans and chimpanzees. Whereas only one KIR2DL4 molecule is detected in humans and chimpanzees, two distinct KIR2DL4 homologues were identified in the monkeys. Although the two human KIR3DL molecules are limited in their polymorphism, the KIR3DL homologues in the monkeys were highly polymorphic. Up to five KIR3DL homologues were identified in each monkey that was studied, and eleven distinct KIR3DL molecules were detected in the five rhesus monkeys. Two novel families of KIR molecules were identified in the rhesus monkeys, KIR3DH and KIR1D. The KIR3DH molecules have three Ig domains, transmembrane domains homologous to KIR2DL4 molecules that contain an arginine, and short cytoplasmic domains. With these features, the KIR3DH molecules resemble the activating forms of the human KIR molecules. The KIR1D molecule encodes only one complete Ig domain before a frame-shift in the second Ig domain occurs, leading to early termination of the molecule. Multiple splice variants of KIR1D exist that encode at least one Ig domain, as well as transmembrane and cytoplasmic domains. The extensive diversity of the rhesus monkey KIR3DL homologues and the novel KIR3DH and KIR1D molecules suggests that the KIR family of molecules has evolved rapidly during the evolution of primates.

Effect of high altitude (7,620 m) exposure on glutathione and related metabolism in rats

Reduced and oxidised glutathione (GSH and GSSG) contents, and glutathione reductase, and glutathione S-transferase activities were studied in the livers, muscles, and blood/erythrocytes of male Sprague-Dawley rats exposed to intermittent hypoxia (6 h.day-1) at a simulated altitude of 7,620 m for 1, 7, 14, and 21 days. Significant decreases in GSH and increases in GSSG contents were observed in the muscles and blood of hypoxia-exposed rats in comparison to unexposed rats. Significant declines in GSH content by 43% and 45% respectively in muscles and blood were observed in the group exposed for 1 day which tended to recover on subsequent exposure. Glutathione reductase and glutathione S-transferase activities were decreased in the livers and erythrocytes of hypoxia-exposed rats, but were increased significantly in muscle. Lipid peroxidation was also increased in the livers and muscles of exposed rats. The changes were indicative of an increased production of reactive oxygen species and an impairment of drug and xenobiotic metabolism during exposure to high altitude hypoxia.

Mechanism of increased tolerance to hypothermia after composite Indian herbal preparation II administration

OBJECTIVE

Investigation of the mechanism of increased tolerance to stress induced hypothermia after the administration of composite Indian herbal preparation II (CIHP II), a combination of several plant ingredients and minerals.

DESIGN

The effect of oral CIHP II administration (1 mg/g of body weight), prior to cold (5 degrees C)-hypoxia (428 mm Hg)-restraint (C-H-R) exposure in rats on cardiac and skeletal muscle oxidation was studied in vitro by estimating conversion of glucose-U-14C and Palmitate-1-(14)C to 14CO2. In vitro adipose tissue lipolysis and incorporation of glucose-U-14C into skeletal muscle glycogen was also studied.

RESULTS

A single dose of CIHP II-enhanced resistance to hypothermia (rectal temperature [T(rec)] 23 degrees C) during C-H-R exposure as evidenced by increased glucose turnover rate in heart and skeletal muscle tissue. The blood glucose and skeletal muscle glycogen were conserved. Cardiac free fatty acid oxidation was also increased. During recovery from hypothermia (T(rec) 37 degrees C) blood glucose and muscle glycogen levels were conserved. Five doses of CIHP II increased resistance to cold by increased adipose fat mobilization and cardiac oxidation. Glucose oxidation was spared. During recovery from hypothermia, the glucose turnover and oxidation in skeletal muscle was increased as was fat mobilization from adipose tissue and its oxidation by heart muscle.

CONCLUSIONS

CIHP II intake prior to C-H-R exposure resulted in increased glucose turnover rate and fat utilization. This perhaps helped increase the resistance to C-H-R-induced hypothermia and speeded recovery.

Degradation and de novo synthesis of D1 protein and psbA transcript levels in Chlamydomonas reinhardtii during UV-B inactivation of photosynthesis and its reactivation

UV-B induces intensity and time dependent inhibition of photosynthetic O2 evolution and PS II electron transport activity in Chlamydomonas reinhardtii. The D1 and D2 proteins of chloroplast membranes are rapidly and specifically degraded in the course of irradiation of cells to UV-B. Continuous synthesis of the two proteins was essential for the repair of damaged PS II as chloramphenicol accelerated UV-B inactivation of photosynthesis and prevented photoreactivation. Northern analysis revealed that UV-B also affected the expression of psbA gene coding for the D1 protein. Cells showing 72% inhibition of PS II activity, revealed a modest net loss of 25% in the level of D1 protein. This shows that synthesis of D1 protein is not the only component involved in the recovery process. Our results indicate that besides affecting the synthesis of the D1 protein UV-B may impair certain post-translational events, which in turn may limit the repair of damaged PS II.

Enhanced thermogenesis in rats by a composite Indian herbal preparation-I and its mechanism of action

OBJECTIVE

A composite Indian herbal preparation-I (CIHP-I) containing ingredients derived from 7 different plants and asphalt was tested for its adaptogenic activity and its mechanism of action was investigated.

DESIGN

CIHP-I was tested using the cold-hypoxia-restraint (C-H-R) animal model in which the restrained rats were exposed to 5 degrees C at 428 mm Hg atmospheric pressure. Rectal temperature (Trec) of the rats was continuously monitored during the exposure and the recovery periods. The time for fall of Trec to 23 degrees C and its recovery to 37 degrees C were used as indices of endurance and the adaptogenic activity. Carbohydrate and lipid parameters were investigated to find out the nature of fuel being used during thermogenesis.

RESULTS

After 12 weeks of administration of an oral dose of 7.5 mg/kg(-1)/day(-1), CIHP-I was found to possess significant adaptogenic activity. CIHP-I helped improve resistance to C-H-R induced hypothermia (Trec 23 degrees C) in animals by increased mobilization of free fatty acids (FFA) from adipose tissue. Blood glucose and muscle glycogen levels were maintained. CIHP-I treatment restricted the release of creatine phosphokinase (CPK) into the circulation during C-H-R exposure.

CONCLUSIONS

The results suggested that CIHP-I is a strong adaptogen. It improved cold resistance during C-H-R exposure and enhanced recovery from hypothermia. The energy-dependent cell membrane permeability was maintained. Stored lipids were mobilised and possibly used for thermogenesis in preference to carbohydrates.

Enhanced thermogenesis in rats by Panax ginseng, multivitamins and minerals

Substances which enhance endurance for physical and mental work and increase non-specific resistance to stress during a prolonged stay in physiologically adverse habitats are called 'adaptogens'. Panax ginseng is well known for its anti-stress and adaptogenic properties. In the present study, adaptogenic activity by the intake of a herbo-vitamin-mineral preparation (HVMP) containing P. ginseng and multivitamin-mineral preparation (MVMP) was evaluated using the cold-hypoxia-restrained (C-H-R) animal model. The aim was to determine whether the cold tolerance and recovery from acute hypothermia mediated by P. ginseng was modified by simultaneous intake of additional vitamins and minerals. Results suggest that the adaptogenic effect of HVMP was more or less the sum total of its two components P. ginseng and MVMP. In HVMP, P. ginseng was found to be effective for developing resistance to cooling and MVMP helped in stimulating faster recovery from acute hypothermia.

Reactivation of photosynthesis in the photoinhibited green alga Chlamydomonas reinhardtii: Role of dark respiration and of light

Effect of quality, quantity and minimum duration of light on the process of recovery was investigated in the photoinhibited cells of the green alga Chlamydomonas reinhardtii. Complete and rapid reactivation of photosynthesis took place in diffuse white light of 25 μmol m(-2) s(-1). The recovery was partial (< 10%) in the dark. Far red (725 nm), red (660 nm) and blue light (480 nm) in the range of 10 to 75 μmol m(-2) s(-1) did not enhance the process of reactivation. Photoinhibited cells incubated in dark for 15 min when exposed for 5 min to diffuse light (25 μmol m(-2) s(-1)) showed complete reactivation. Even exposure of 15 min dark incubated photoinhibited cells to photoinhibitory light (2500 μmol m(-2) s(-1)) for 5 s fully regained the photosynthesis. The study indicated a very precise and triggering effect of light in the process of reactivation. The dark respiratory inhibitor KCN and uncouplers FCCP and CCCP increased the susceptibility of C. reinhardtii to photoinhibition and also prevented photoinhibited cells to reactivate fully even after longer period of incubation under suitable reactivating conditions. Of the various possibilities envisaged to assign the role of dark respiration in recovery process, supply of ATP by mitochondrial respiration appeared sound and pertinent.