siRNA-Based Novel Therapeutic Strategies to Improve Effectiveness of Antivirals: An Insight

Since the ground-breaking discovery of RNA interference (RNAi), scientists have made significant progress in the field of small interfering RNA (siRNA) treatments. Due to severe barriers to the therapeutic application of siRNA, nanoparticle technologies for siRNA delivery have been designed. For pathological circumstances such as viral infection, toxic RNA abnormalities, malignancies, and hereditary diseases, siRNAs are potential therapeutic agents. However, systemic administration of siRNAs in vivo remains a substantial issue due to a lack of "drug-likeness" (siRNA are relatively larger than drugs and have low hydrophobicity), physiological obstacles, and possible toxicities. This write-up covers important accomplishment in the field of clinical trials and patents specially based of siRNAs using targeting viruses. Furthermore, it offers deep insight of nanoparticle applied for siRNA delivery and strategies to improve the effectiveness of antivirals.

Flap versus Flapless Immediate Implants with Bone Augmentation: A Novel Study

Background

This study aimed to equate implants placed using a traditional flap elevation technique with implants placed using a flapless process regarding bone healing and success in clinical conditions.

Materials and Methods

Sixty subjects were included in this research work. The participants were randomly divided into two groups. Patients in group A underwent implant placement with the flap elevation technique. Similarly, group B patients underwent implant placement without flap reflection. Parameters such as plaque index, wound healing index, crestal bone loss, and radiograph were considered to estimate the effectiveness of the two techniques.

Results

Plaque indexes were improved in both groups. The modified gingival index also improved in all the phases of healing. The flapless method showed a better crestal bone.

Conclusion

It can be concluded that this study showed that with the right augmentation techniques, implants could be successfully performed immediate extraction sockets, both with and without elevation of the mucoperiosteal flap.

Optimized security algorithm for connected vehicular network

Purpose

As the number of devices that connect to the Internet of Things (IoT) has grown, privacy and security issues have come up. Because IoT devices collect so much sensitive information, like user names, locations, phone numbers and even how they usually use energy, it is very important to protect users' privacy and security. IoT technology will be hard to use on the client side because IoT-enabled devices do not have clear privacy and security controls.

Design/methodology/approach

IoT technology would be harder to use on the client side if the IoT did not offer enough well-defined ways to protect users’ privacy and security. The goal of this research is to protect people's privacy in the IoT by using the oppositional artificial flora optimization (EGPKC-OAFA) algorithm to generate the best keys for the ElGamal public key cryptosystem (EGPKC). The EGPKC-OAFA approach puts the most weight on the IEEE 802.15.4 standard for MAC, which is the most important part of the standard. The security field is part of the MAC header of this standard. In addition, the MAC header includes EGPKC, which makes it possible to make authentication keys as quickly as possible.

Findings

With the proliferation of IoT devices, privacy and security have become major concerns in the academic world. Security and privacy are of the utmost importance due to the large amount of personally identifiable information acquired by IoT devices, such as name, location, phone numbers and energy use. Client-side deployment of IoT technologies will be hampered by the absence of well-defined privacy and security solutions afforded by the IoT. The purpose of this research is to present the EGPKC with optimum key generation using the EGPKC-OAFA algorithm for the purpose of protecting individual privacy within the context of the IoT. The EGPKC-OAFA approach is concerned with the MAC standard defined by the IEEE 802.15.4 standard, which includes the security field in its MAC header. Also, the MAC header incorporates EGPKC, which enables the fastest possible authentication key generation. In addition, the best methodology award goes to the OAFA strategy, which successfully implements the optimum EGPKC selection strategy by combining opposition-based (OBL) and standard AFA ideas. The EGPKC-OAFA method has been proved to effectively analyze performance in a number of simulations, with the results of various functions being identified.

Originality/value

In light of the growing prevalence of the IoT, an increasing number of people are becoming anxious about the protection and confidentiality of the personal data that they save online. This is especially true in light of the fact that more and more things are becoming connected to the internet. The IoT is capable of gathering personally identifiable information such as names, addresses and phone numbers, as well as the quantity of energy that is used. It will be challenging for customers to adopt IoT technology because of worries about the security and privacy of the data generated by users. In this work, the EGPKC is paired with adversarial artificial flora, which leads in an increase to the privacy security provided by EGPKC for the IoT (EGPKC-OAFA). The MAC security field that is part of the IEEE 802.15.4 standard is one of the areas that the EGPKC-OAFA protocol places a high focus on. The Authentication Key Generation Protocol Key Agreement, also known as EGPKCA, is used in MAC headers. The abbreviation for this protocol is EGPKCA. The OAFA technique, also known as the combination of OBL and AFA, is the most successful method for selecting EGPKCs. This method is recognized by its acronym, OAFA. It has been shown via a variety of simulations that the EGPKC-OAFA technique is a very useful instrument for carrying out performance analysis.

Nano-strategies as Oral Drug Delivery Platforms for Treatment of Cancer: Challenges and Future Perspectives

Oral drug administration is the oldest and widely used method for drug administration. The objectives behind developing an oral drug delivery for the treatment of cancer are to achieve low cost treatment by utilizing novel techniques to target cancer through gut-associated lymphoid tissue (GALT) and to enhance patient comfort and compliance through a hospital-free treatment leading to "Chemotherapy at Home." Unfortunately, due to the physiological environment of the GIT and physicochemical properties of drug candidate, the efficacy of oral drug delivery methods is limited in the treatment of cancer. Due to their low hydrophilicity, high P-gp efflux and restricted intestinal permeability most of the anti-cancer drugs fail to achieve oral bioavailability. The review focuses on the efforts, challenges, opportunities and studies conducted by scientists worldwide on the oral administration of anticancer medications via nanocarriers such as liposomes, SLNs and dendrimers, because of their potential to overcome the epithelial barrier associated with GALT, as well as the applications of different polymers in targeting the cancer. The oral delivery can set newer horizons in cancer therapy to make it more patient friendly.

National Survey to Describe the Current Patterns of Procedural Sedation Practices Among Pediatric Emergency Medicine Practitioners in the United States

OBJECTIVE

Pediatric procedural sedation (PPS) is used to maintain children's safety, comfort, and cooperation during emergency department procedures. Our objective was to gather data describing PPS practice across the United States to highlight the variations in practice and adherence to National Guidelines.

METHODS

We performed a nationwide survey of PPS practitioners using a secure web-based software program. A link to the survey was sent to all subscribers of a pediatric emergency medicine listserv. We collected participant demographics, their PPS approach for personnel, monitoring, equipment, postsedation observation, and side effects, as well as providers' medication preferences for 3 common PPS scenarios.

RESULTS

We received 211 completed surveys from 34 States. There were 20.6% respondents that were based in New York, 83.4% were pediatric emergency medicine attendings, and 91.7% were based in the United States teaching hospitals. Our participants learned PPS by various methods, most commonly: observation of at least 10 PPS (29.9%); self-study (24.8%); and classroom lectures (24.5%). Seventy-seven percent of our participants reported no body mass index cutoff to do PPS. There were 31.5% of our participants that observe children after PPS up to 1 hour, 30.1% up to 2 hours. There were 67.7% of the PPS providers that were a separate person from the practitioner doing the procedure, and 98.2% required a separate trained nurse to be present for monitoring. There were 92.6% of PPS providers that measure end-tidal carbon dioxide (ETCO2) during the sedation. Most PPS providers reported having no reversal agents (71.4%) and no defibrillator (65.9%) at bedside. For the abscess drainage scenario, 22% of participants preferred local anesthetic alone, and 22.5% preferred utilizing local anesthetic in combination with intravenous ketamine. For a forearm fracture reduction scenario, 62.8% of participants would choose intravenous ketamine alone. For the laceration repair scenario, the most favored drug combination was local anesthesia + intranasal midazolam by 39.8% of participants.

CONCLUSIONS

Our study demonstrates a wide variability in several aspects of PPS and low adherence to national PPS guidelines.

Formulation and Characterization of Febuxostat Loaded Nanostructured Lipid Carriers (NLCs) - Gel for Topical Treatment of Gout

BACKGROUND

The aim of the present study was to formulate and characterize Nano- Structured Lipid Carriers (NLCs) of Febuxostat (FB) incorporated in the gel for the treatment of Gout. FB is a Xanthine Oxidase (XO) inhibitor drug used for chronic Gout and hyperuricemia. FB is a BCS class II drug, therefore, water solubility is very poor, and due to its poor solubility and wettability, it leads to poor dissolution. The hot high-pressure homogenization technique was used in this study to improve the physicochemical property of FB.

METHODS

The carbopol 934 was used to prepare NLCs gel of FB. The NLCs of FB was prepared in different drug: polymer ratios w/w (2:1), (1:1), (1:2), (1:3) and (1:4) with solid lipid (Stearic Acid) and liquid lipid (Oleic acid). The preformulation study of FB included FTIR study melting point, standard calibration curves, and drug-polymer interaction study.

RESULTS

The NLCs (1:3) showed high entrapment and drug content. The NLCs gel formulation was 87% released within 6 hours in a controlled manner.

CONCLUSION

NLCs gel modifies the drug release, increases the bioavailability, and reduces side effects of FB. The prepared gel is the efficient formulation for the better treatment of chronic gout and hyperuricemia. The research findings have shown the undesirable side effects associated with the oral route that can be reduced by the use of NLCs formulation through the transdermal route in an effective manner.

Pneumorrhachis in a Pediatric Patient with an Isolated Back Injury

BACKGROUND

Pneumorrhachis is an uncommon radiographic finding and is typically found in adult patients secondary to trauma or pneumocephalus. It is extremely rare in the pediatric population. Our case report describes a young boy who was found to have pneumorrhachis, but initially presented with an isolated back laceration.

CASE REPORT

An 8-year-old boy arrived to the emergency department as a transfer from an outside hospital after initially presenting with a back laceration. After laceration repair, he developed severe headache and vomiting when sitting upright from a supine position. He was found to have T3 fractures and pneumocephalus secondary to pneumorrhachis and was managed conservatively per neurosurgery recommendations. Why Should an Emergency Physician Be Aware of This?Although extremely rare in the pediatric population, pneumorrhachis must still be considered in any pediatric patient with a penetrating injury to the abdomen, respiratory tract, or spinal column. Cases without clear etiology require further evaluation for occult spinal injuries and fractures. Conservative management is typically sufficient, although certain situations require further intervention.

Implementation of Electronic Medical Record Template Improves Screening for Complications in Children with Type 1 Diabetes Mellitus

Objective

Health professionals and patients should follow comprehensive screening guidelines to recognize early signs of long-term complications for insulin-dependent type 1 diabetes mellitus (T1DM). The aim of this study is to demonstrate that utilization of electronic medical record (EMR) templates for diabetes management improves adherence to International Society for Pediatric and Adolescent Diabetes (ISPAD) screening guidelines.

Methods

All patients with T1DM who were seen in the outpatient pediatric endocrine clinic (age 0–22 years old) at an urban community-based community hospital during the 2014 calendar year were enrolled in the study (n=49). A retrospective chart review was performed and audited against ISPAD guidelines. An EMR template and order set was then created based on ISPAD screening guidelines with the aim of improving compliance. The templates were implemented in 2015 (initial phase) and 2016 (maintenance phase) and these data were compared to baseline data. A chi-squared test was performed to analyze the differences between the data using SAS version 9.4 (SAS Institute, Inc). A p-value less than 0.05 was considered significant.

Results

Significant improvements (p< 0.05) in screening guideline adherence from baseline to maintenance phase data were found for annual retinopathy (0% to 45%) and neuropathic foot (0% to 64%) exams, screening for microalbuminuria (49% to 79%), celiac disease (6% to 81%), lipids (63% to 86%), and basic metabolic panel (69% to 88%). Of note, thyroid function testing was also increased, but was not statistically significant between the years.

Conclusion

The utilization of EMR templates and order sets for T1DM are valuable tools to aid medical providers in adhering to ISPAD screening guideline.

Withdrawal Notice: Mucoadhesive Microspheres: An Emerging Trends in Therapy of Diabetes Mellitus

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The association between vitamin D deficiency and hospitalization outcomes in pediatric patients with sickle cell disease

BACKGROUND

While there is a known association between low vitamin D levels and increased chronic pain in patients with Sickle Cell Disease (SCD), there are no reported studies evaluating the relationship of vitamin D levels and hospitalization outcomes in this population. The aim of this study was to assess this relationship with hospitalization outcomes defined as the number of emergency room (ER) visits, hospital admissions for pain crisis, and length of hospital stay.

DESIGN

A retrospective chart review of all pediatric patients with SCD (1-21 years old) was performed from January 2015 to January 2016 in an urban-based hospital setting (n = 134). Those with at least one reported Vitamin D level who maintained follow up during the time studied were enrolled (n = 90). Patient hospitalizations rates were compared between vitamin D deficiency (<20 ng/ml) and sufficiency (>20 ng/ml).

RESULTS

Patients with both SCD and vitamin D deficiency were more likely to have at least one Emergency Room visit (p < 0.01), at least one admission for pain crisis (p < 0.01), and a longer length of admission (p < 0.0001) when compared to patients with SCD and sufficient vitamin D levels.

CONCLUSION

There is a significant association between vitamin D levels of <20 ng/ml and the number of ER visits, hospital admissions for pain crisis, and length of stay in patients with SCD. Further research is required to assess if correcting vitamin D levels may improve hospitalization outcomes in this population.

Formulation of Herbal Fast Disintegrating Tablets and its ex-vivo Study for Anti-histaminic Activity in Guinea Pig Ileum

OBJECTIVE

The aim of present research work was to develop a herbal fast disintegrating tablet containing Fagonia schweinfurthii Hadidi dried extract and determining its antihistaminic activity using guinea pig ileum.

METHOD

The tablets were formulated by wet granulation technique using three different superdisintegrants (croscarmillose, crospovidone and sodium starch glycolate) at three different levels. The tablets were evaluated for various physical properties like hardness, friability weight variation etc. and various mechanical properties like disintegration time, wetting time to select the best superdisintegrant. The selected superdisintegrant was further used as intra as well as extra granulating agent to develop fast disintegrating tablets of Fagonia schweinfurthii Hadidi dried extract. The optimized formulation was subjected to stability study as per the ICH guidelines. Finally, Ex-vivo antihistaminic study was conducted on guinea pig ileum for optimized formulation and compared with marketed tablet containing cetrizine HCl as API (Stanhist-10, Ranbaxy, Pvt. Ltd).

RESULTS

Physical properties of all tablet batches were found to be acceptable and comply with various official specifications. The disintegration time and wetting time of optimized formulation (F'3) were found to be 1.15±0.08 and 0.56±0.04 min respectively. Results of Ex-vivo study showed a comparable histamine inhibition between optimized tablet (15%) and marketed tablet formulation (18.8%) in a dose of 5 µg/ml.

CONCLUSION

On the basis of in-vitro and Ex-vivo studies, it was concluded that prepared herbal fast disintegrating tablets were stable and had potent antihistaminic activity.

Rational Design and Synthesis of Biologically Active Disubstituted 2(3H) Furanones and Pyrrolone Derivatives as Potent and Safer Non Steroidal Anti-inflammatory Agents

BACKGROUND

Furanone and pyrrolone heterocyclic ring system represent important and interesting classes of bioactive compounds. Medicinal chemists use these heterocycyclic moieties as scaffolds in drug design and discovery.

METHODS

A series of 3-arylidene-5-(naphthalene-2-yl)-furan-2(3H)-ones (2a-j) were synthesized by incorporating pharmacophore of COX-2 inhibitor rofecoxib and naphthyl ring of naproxen as potential non steroidal anti-inflammatory agents. These furanone derivatives were subsequently reacted with dry ammonia gas and benzylamine to furnish corresponding 3-arylidene-5-(naphthlen-2-yl)-1H-pyrrol-2(3H)-ones (3a-e) and 3-arylidene-1-benzyl-5- (naphthalene-2-yl)-1H-pyrrol-2(3H)-ones (4a-e), respectively. The newly prepared heterocyclics were screened for their expected in-vivo biological activities including anti-inflammatory, analgesic and ulcerogenic actions in rodents. The COX-2 inhibitory behavior of synthesized compounds was also assessed via automated docking studies.

RESULTS

The chemical structure of the synthesized compounds was characterized by using modern spectroscopic techniques. Result of in-vivo pharmacological studies demonstrated that almost all N-Benzyl-pyrrol-2(3H)-ones (4a-e) showed better anti-inflammatory and analgesic activities in comparison with the other two series of furan-2(3H)-ones and pyrrol- 2(3H)-ones. The moldock score value of the tested compounds was found in the range of -116.66 to -170.328 and was better than the standard drug.

CONCLUSION

Among all the synthesized compounds, only nine compounds (2d, 2g, 2h, 3d, 4a, 4b, 4c, 4d and 4e) exhibited potent anti-inflammatory and analgesic activities with significantly reduced gastrointestinal toxicity in various animal models in comparison to standard drug, diclofenac. Therefore, it is recommended to explore the potential of the synthesized compounds as lead candidates for the development of new therapeutic agents.

On water: silver-catalyzed domino approach for the synthesis of benzoxazine/oxazine-fused isoquinolines and naphthyridines from o-alkynyl aldehydes

An operationally simple domino approach for the silver-catalyzed synthesis of oxazine/benzoxazine-fused isoquinolines 5a-q and naphthyridines 6a-v by the reaction of o-alkynyl aldehydes 3a-aa with amines having embedded nucleophiles 4a-d under mild reaction condition in water is described. The reaction shows selective C-N bond formation on the more electrophilic alkynyl carbon resulting in the formation of 6-endo-dig cyclized product. The competitive experiments show the viability of an intramolecular nucleophilic attack over an intermolecular attack of the external nucleophile. This methodology accommodates wide functional group variation, which proves to be useful for structural and biological assessment.

Isolated fallopian tube torsion in early pregnancy presenting as resolving appendicular lump

Isolated fallopian tube torsion (IFTT) is a rare clinical entity, especially in pregnancy. It is frequently misdiagnosed as acute appendicitis or ovarian torsion. We present an unusual case of IFTT occurring in early pregnancy, which was detected when patient presented for medical termination of pregnancy in family planning clinic. This case report highlights sub acute presentation of IFTT in early pregnancy which clinically presented as resolving appendicular lump.

CYP1B1, a developmental gene with a potential role in glaucoma therapy

The association of CYP1B1 gene alterations in primary congenital glaucoma individuals has been known for about a decade. Recent evidence has shown the involvement of CYP1B1 mutations in a number of forms of glaucoma and anterior segment disorders. This suggests a wide role for CYP1B1 in ocular physiology. Histochemical studies of eyes from individuals with primary congenital glaucoma revealed abnormalities in the anterior chamber angle, the region between the cornea and the iris, containing the trabecular meshwork. The cells of the trabecular meshwork serve as a filter to allow drainage of the aqueous humour, the fluid formed by the ciliary body that fills the anterior chamber. Mutations in CYP1B1 that affect its activity have frequently been shown to influence development of the trabecular meshwork, and it is thought that CYP1B1, a monooxygenase, acts to form or degrade some endobiotic compound that is necessary for proper development of the filtering structures. The rapidly developing area of stem cell research suggests a potential therapeutic approach for glaucomas resulting from deleterious mutations in CYP1B1, that is, the transfer of stem cells, differentiated to a specific lineage, containing wild-type CYP1B1 to specific regions of the eye, where they will develop into normal cells of that region and rectify the defect.

Physiological Significance and Expression of P450s in the Developing Eye

Expression of 10 CYP orthologs (Families 1-3) in developing mouse conceptus is constitutive. These forms have specific temporal and spatial expression. Studies on CYP1B1 indicate its requirement for normal eye development, both in human and mouse. The distribution of the enzyme in the mouse eye is in three regions, which may reflect three different, perhaps equally important, functions in this organ. Its presence in the inner ciliary and lens epithelia appears to be necessary for normal development of the trabecular meshwork and its function in regulating intraocular pressure. Its expression in the retinal ganglion and inner nuclear layers may reflect a role in maintenance of the visual cycle. Its expression in the corneal epithelium may indicate a function in metabolism of environmental xenobiotics.

Comparative expression profiling of 40 mouse cytochrome P450 genes in embryonic and adult tissues

This study is the first systematic investigation of the gestational age-dependent and adult tissue-specific expression patterns of each known mouse CYP family (40 genes) using normalized cDNA panels and uniform reverse transcriptase polymerase chain reaction-based assays. Twenty-seven of the P450s were constitutively expressed during development. The number gradually increased through the phases of gastrulation E7 (n=14), neural patterning and somitogenesis E11 (n=17), organogenesis E15 (n=20), and fetal period E17 (n=21). Cyp2s1, Cyp8a1, Cyp20, Cyp21a1, Cyp26a1, Cyp46, and Cyp51 were detected in each of the four stages studied. Members of family CYP1 demonstrated complex, nonoverlapping embryonic patterns of expression, indicating that Cyp1a1 and Cyp1a2 may not compensate for Cyp1b1 deficiency associated with abnormal eye development. Multiple Cyp forms were found to be constitutively expressed in each of the adult tissues studied: liver (n=31), kidney (n=30), testis (n=26), lung (n=24), and heart (n=13). The tissue-specific P450-expression profiles reported in this study provide a reference for more focused analysis of the tissue-specific and developmental functions of the cytochrome P450 monooxygenases.

Modulation of glyoxalase, glutathione S-transferase and antioxidant enzymes in the liver, spleen and erythrocytes of mice by dietary administration of fenugreek seeds

There is a growing interest in understanding the biological effect of time-tested folk medicinal plants. In the present work, the effect of dietary administration of fenugreek seeds on the glyoxalase system and antioxidant enzymes as well as levels of glutathione (GSH) have been examined in different tissues of mice. Swiss albino mice were fed with diet containing powdered fenugreek for 4 weeks. The mode and magnitude of effect was found to depend on the dose of fenugreek and type of tissue. The diet containing 1 and 2% of fenugreek enhanced the specific activity of gly I, whereas 5 and 10% inhibited its activity in the liver. However, on the other hand, the specific activity of gly II decreased continuously with dose. Dietary administration of fenugreek seeds resulted in an increase of GSH levels and the glutathione S-transferase (GST) activity in the liver. Fenugreek (1 and 2%) showed no appreciable change in superoxide dismutase (SOD) and catalase. However, 5 and 10% doses of fenugreek supplementation inhibited their activities. In the case of spleen, a significant change in gly I was observed only at 10% fenugreek. In addition, a significant increase was also observed with GSH levels. Fenugreek treatment up to 5% showed a small but consistent increase in erythrocytes. In the case of GST, the activity enhanced with dose. Significant elevation of catalase activity was observed with a 10% dose of fenugreek. The significance and relevance of these findings are suggested in relation to mechanistic aspects.

Radiation induced oxidative stress: I. Studies in Ehrlich solid tumor in mice

Understanding the response of tumors to ionizing radiation might potentially lead to improvement in tumor control and patient morbidity. Since the antioxidant status is likely to be linked to radioresponse, its modulation needs to be examined. Therefore, Swiss albino male mice (7-8 weeks old) with Ehrlich solid tumors were irradiated with different doses of gamma rays (0-9 Gy) at a dose rate of 0.0153 Gy/s; and enzymes involved in antioxidant functions were determined in the tumors. Radiation effects in terms of oxidative damage, LDH, nitric oxide and DNA fragmentation were also examined. In tumors, the specific activity of SOD was increased with dose but declined 6 Gy onwards. GST, DTD and GSH showed an almost progressive increase. These enhanced activities might have resulted from the increased protein expression. This possibility was supported by the Western Blot analysis for GST protein. These changes might be closely linked to the radiation-induced oxidative stress as reflected by the enhanced levels of peroxidative damage, DNA fragmentation, LDH activity and nitric oxide levels. These findings may have relevance to radiation therapy of cancer as the elevated antioxidant status of irradiated tumors is likely to limit the effectiveness of radiation dose and adversely affect the therapeutic gain.

Modulation of radioresponse of glyoxalase system by curcumin

Human beings have been exposed to radiation for many years. It is quite possible that antioxidant phytochemicals consumed in their diet might be providing a variable degree of radioprotection. However, their radiomodifying ability is not well understood. In the present work, curcumin (diferuloyl methane), a phytochemical present in the rhizome of Curcuma longa Linn. has been examined for its radioprotective property using the glyoxalase system which is vital for various biological functions. Curcumin (5, 25 and 50 mg/kg body weight) in olive oil was given orally to Swiss albino male mice (7-8 weeks old) daily for 2 weeks and irradiated with different doses of gamma-radiation (0-6 Gy) at 0.027 Gy per second dose rate on last day of the treatment. The specific activities of glyoxalase I and II were determined in the liver and spleen. The treatment of curcumin prior to irradiation restored the specific activity of glyoxalase system to almost the control level which was suggestive of the radioprotective ability of curcumin. Free radical scavenging and electron/hydrogen donation are probable attributes for the protective effect of curcumin.

Effect of high linear energy transfer radiation on biological membranes

Cellular membranes are vital elements, and their integrity is extremely essential for the viability of the cells. We studied the effects of high linear energy transfer (LET) radiation on the membranes. Rabbit erythrocytes (1 x 10(7) cells/ml) and microsomes (0.6 mg protein/ml) prepared from liver of rats were irradiated with 7Li ions of energy 6.42 MeV/u and 16O ions of energy 4.25 MeV/u having maximum LET values of 354 keV/microm and 1130 keV/microm, respectively. 7Li- and 16O-induced microsomal lipid peroxidation was found to increase with fluence. The 16O ions were more effective than 7Li ions, which could be due to the denser energy distribution in the track and the yield of free radicals. These findings suggested that the biological membranes could be peroxidized on exposure to high-LET radiation. Inhibition of the lipid peroxidation was observed in the presence of a membrane-active drug, chlorpromazine (CPZ), which could be due to scavenging of free radicals (mainly HO* and ROO*), electron donation, and hydrogen transfer reactions. The 7Li and 16O ions also induced hemolysis in erythrocytes. The extent of hemolysis was found to be a function of time and fluence, and showed a characteristic sigmoidal pattern. The 16O ions were more effective in the lower fluence range than 7Li ions. These results were compared with lipid peroxidation and hemolysis induced by gamma-radiation.

Influence of methylglyoxal on antioxidant enzymes and oxidative damage

The effect of different doses of methylglyoxal (50-400 mg/kg body wt.) were examined using enzymes involved in the antioxidant function, glutathione (GSH) content and lipid peroxidation in the liver and spleen of Swiss albino mice (7-8 week old) after 6, 12 and 24 h. Significant changes were observed predominantly in the liver. The specific activities of superoxide dismutase (SOD), glutathione-S-transferase (GST), catalase, glyoxalase I (gly I) and glyoxalase II (gly II) were found to decrease in the liver. The mode and magnitude of change in the specific activities was seen to depend on the dose of methylglyoxal and the time after its administration. Methylglyoxal also decreased the GSH content and enhanced the lipid peroxidation in the liver. These findings are suggestive of the adverse effect of methylglyoxal on the antioxidant defence system. It is likely that methylglyoxal undergoes a redox cycle and generates the free radicals which in turn lower the antioxidant status in animals. The increased levels of lipid peroxidation provide support for the involvement of free radical processes in the detrimental effects of methylglyoxal. The response of DT-diaphorase (DTD) seems to be adaptive.