Thursday, May 15, 2008

Niosomes

Liposomes have following members in its family:
2. Virosomes
3. Niosomes
4. Archaeosomes
6. Cochleates
7. Proteosomes (Gideon F. A. Kersten et al.)

Introduction of Niosomes:
Niosomes are unilamellar or multilamellar vesicles [3] which are very similar to liposomes in structure, prepared primarily from non-ionic surfactant vesicles. They are one of the most studied alternative to liposomes. Niosomes can be changed or modified by the incorporation of other excipients like cholesterol, into the membrane and they can possess one or more lipid bilayers encapsulating an aquous core. A diverse range of materials have been used to form niosomes such as sucrose ester surfactants and polyoxyethylene alkyl ether surfactants. [1]

(D. Paolina) Niosome vesicles were prepared with the thin layer evaporation method and were physico-chemically characterized. (R. M. Handjani-Vila et al.)In comparison with classical formulations such as emulsions, these systems exhibit lower toxicity and permit closer control of the availability of active substances at the stratum corneum.

Preparation of Niosomes:

(A. J. Baillie et al.) Vesicles were prepared on hydration of a mixture of a single or double alkyl-chain, non-ionic surfactant with cholesterol. These vesicles, or 'niosomes', are capable of entrapping and retaining water soluble solutes such as carboxyfluorescein, are osmotically active and can be formulated to release entrapped solute slowly.

Properties of Niosomes:
There is good entrapment efficiency in niosomes. (T. Yoshioka et al.)There is increased efficiency of entrapment of molecules with increasing cholesterol content. Studies show that (Maria Manconi et al.) small, niosomal formulations,(which are saturated with tretinoin) charged negatively, give higher cutaneous drug retention than both liposomes and commercial formulation in the area of study.

This is one of the representation of the Niosome. Here "o" represents "Hydrophilic head group"and "--" represents "Hydrophobic tail"

Characteristics of the head and tail groups:


Hydrophilic head may consist of the following groups:

1. Ethylene Oxide head groups
2. Polyhydroxy head groups
3. Glycerol head groups
4. Crown ether head groups
5. Sugar head groups i.e. Mannose, lactose, glucose, galactose

Hydrophobic tail may consist of the following groups:
1. Perfluoroalkyl surfactants that form vesicles having chain lengths as short as C10
2. One or two alkyl or perfluoroalkyl groups or in certain cases a single steroidal group.
3. Additionally crown ether amphiphiles bearing a steroidal C14 alkyl or C16 alkyl hydrophobic unit have been shown to form vesicles
4. Alkyl group chain length is usually from C12-C18 (one, two or three alkyl chains).
Preference of Niosomes over liposomes:
Niosomes are now preferable on liposomes as
1. They have more stability
2. Different grades of purity in respect of phospholipids and
3. Low cost
4. Non-ionic surfactants can be easily stored

(Ijeoma F. Uchegbu et al.)Following factors affect the Physico-Chemical properties of Niosomes:
1. Choice of surfactants and main or membrane additives.
2. Temperature.
3. Hydration.
4. Size reduction techniques.
5. Natural properties of drugs.

Niosomes are also affected by Addition of kinetic energy which is affected by size reduction techniques.

Different Niosomes:

1. Bola-Surfactant containing niosomes:
(D. Paolino et al.)Niosomes made of alpha,omega-hexadecyl-bis-(1-aza-18-crown-6) (Bola-surfactant)-Span 80-cholesterol (2:3:1 molar ratio) are named as Bola-Surfactant containing niosomes.
2. Proniosomes:
(Chengjiu Hu et al.)A dry product which may be hydrated immediately before use to yield aqueous niosome dispersions. These ‘proniosomes’ minimize problems of niosome physical stability such as aggregation, fusion and leaking, and provide additional convenience in transportation, distribution, storage, and dosing.
In short;
1. Carrier + Surfactants = Proniosomes
2. Proniosomes + H2O = Niosomes
(Adnan Azeem et al.)In case of Frusemide delivery in the body, it has been found that proniosomal formulations have been found effective to sustain the level of drug in the blood.

Uses of Niosomes:
(H. Schreier et al.) Topical liposomes or niosomes may serve
1. as solubilization matrix,
2. as a local depot for sustained release of dermally active compounds,
3. as penetration enhancers,
4. or as rate-limiting membrane barrier for the modulation of systemic absorption of drugs.

(Rita Muzzalupo et al.)Niosomes have shown promise as cheap and chemically stable drug delivery systems. Various uses of Niosomes include Transdermal applications. They cause enhanced delivery of drugs through stratum corneum. Niososmes are also increasingly used for the ocular delivery of drugs for the topical treatment of glaucoma. The niosomal application of both antigens and DNA encoding for antigens results in an enhancement of the humoral and cellular immune response to the said antigens. [2]

Scientists (Donatella Paolino et al.) are researching for topical delivery system by niosomes for 5-fluorouracil (5-FU), largely used in the treatment of different forms of skin cancers.

References:
Transdermal and Topical Drug Delivery: From Theory to Clinical Practice by Adrian C. Williams

Nanoparticulates As Drug Carriers by Vladimir P. Torchilin

Synthetic Surfactant Vesicles: Niosomes and Other Non-Phospholipid Vesicular Systems (Drug Targeting and Delivery) by L. F. Uchegu

Adnan Azeem, Nilu Jain; Zeenat Iqbal; Farhan Jalees Ahmad; Mohammad Aqil; Sushama Talegaonkar, Feasibility of Proniosomes-Based Transdermal Delivery of Frusemide: Formulation Optimization and Pharmacotechnical Evaluation. Pharmaceutical Development and Technology, Volume 13, Issue 2, March 2008 , pages 155 - 163
A. J. Baillie, A.T. Florence , L. R. Hume , G. T. Muirhead , A. Rogerson. The preparation and properties of niosomes--non-ionic surfactant vesicles. The Journal of Pharmacy and Pharmacology. 1985 Dec; 37(12): Pages 863-8.

Chengjiu Hu, David G. Rhodes. Proniosomes: A Novel Drug Carrier Preparation. International Journal of Pharmaceutics, Volume 185, Issue 1, 5 August 1999, Pages 23-35

Donatella Paolino, Donato Cosco, Rita Muzzalupo, Elena Trapasso, Nevio Picci and Massimo Fresta, Innovative bola-surfactant niosomes as topical delivery systems of 5-fluorouracil for the treatment of skin cancer. International Journal of Pharmaceutics, Volume 353, Issues 1-2, 2 April 2008, Pages 233-242

D. Paolino, R. Muzzalupo, A. Ricciardi, C. Celia, N. Picci, M. Fresta. In vitro and in vivo evaluation of Bola-surfactant containing niosomes for transdermal delivery. Biomedical Microdevices. 2007 Aug;9(4): Pages 421-33.
Gideon F. A. Kersten, Daan J. A. Crommelin, Liposomes and ISCOMs. Vaccines, Volume 21, Issues 9-10, 14 February 2003, Pages 915-920

H. Schreier, J. Bouwstra. Liposomes and niosomes as topical drug carriers : dermal and transdermal drug delivery. Journal of Controlled Release 1994, vol. 30, no1, Pages 1-15.

Ijeoma F. Uchegbu, Suresh P. Vyas, Non-ionic surfactant based vesicles (niosomes) in drug delivery. International Journal of Pharmaceutics 172 (1998) Pages 33–70.

Maria Manconi,Chiara Sinico, Donatella Valenti, Francesco Lai and Anna M. Fadda, Niosomes as carriers for tretinoin III. A study into the in vitro cutaneous delivery of vesicle-incorporated tretinoin. International Journal of Pharmaceutics, Volume 311, Issues 1-2, 27 March 2006, Pages 11-19

R. M. Handjani-Vila, A. Ribier, B. Rondot and G. Vanlerberghie. Dispersions of lamellar phases of non-ionic lipids in cosmetic products. International Journal of Cosmetic Science, Volume 1 Issue 5 Page 303-314, October 1979

Rita Muzzalupo, Fiore Pasquale Nicoletta, Sonia Trombino, Roberta Cassano, Francesca Iemma and Nevio Picci. A new crown ether as vesicular carrier for 5-fluoruracil: Synthesis, characterization and drug delivery evaluation. Colloids and Surfaces B: Biointerfaces, Volume 58, Issue 2, 1 August 2007, Pages 197-202.

T. Yoshioka, B. Sternberg, A. T. Florence, Preparation and properties of vesicles (niosomes) of sorbitan monoesters (Span 20, 40, 60 and 80) and a sorbitan triester (Span 85). International journal of pharmaceutics, 1994, vol. 105, no1, Pages 1-6.



Copyright (c), 2011, jeepakistan.blogspot.com

Wednesday, May 14, 2008

Biotechnology

Biotechnology is one of the most interesting fields of science. And in recent years it is developing much more fastly. This field is two way transfer of Biology and Technology. (A. McHughen et al.)The very term 'Biotechnology' elicits a range of emotions, from wonder and awe to downright fear and hostility. This is especially true among non-scientists, particularly in respect of agricultural and food biotechnology. (K. Buchholz et al.) The emergence of biotechnology as a new scientific discipline occurs since 1980s, when it became a major economic force. Significant changes in theoretical perception, research strategies, aims, and experimental methods, mainly in genetic engineering techniques, occurred during this period.

It is the benefit of biotechnology that it enables scientists to work on biofuels. (Durrett, Timothy P. et al.) Triacylglycerols produced by plants are one of the most energy-rich and abundant forms of reduced carbon available from nature. Given their chemical similarities, plant oils represent a logical substitute for conventional diesel, a non-renewable energy source. In this regard, the generation of transgenic soybean lines with high oleic acid content represents one way in which plant biotechnology has already contributed to the improvement of biodiesel.

White biotechnology:
(Munishwar N Gupta et al.)White biotechnology is a fast emerging area that concerns itself with the use of biotechnological approaches in the production of bulk and fine chemicals, biofuels, and agricultural products. (M. Kircher et al.) White biotechnology already produces high volume products such as feed additive amino acids and specialty products like enzymes for enantioselective biocatalysis. It serves large and diverse markets in the nutrition, wellness, pharmaceutical, agricultural and chemical industry.

References:
A. McHughen, Public perceptions of biotechnology. Journal of Biotechnology, 2007 Sep;2(9): Pages 1105-11.

K. Buchholz, Science--or not? The status and dynamics of biotechnology. Journal of Biotechnology, 2007 Sep;2(9): Pages 1154-68.

M. Kircher, White biotechnology: ready to partner and invest in. Biotechnology journal, 2006 Jul-Aug;1(7-8):787-94.

Munishwar N Gupta , Smita Raghava, Relevance of chemistry to white biotechnology. Chemistry Central Journal 2007, 1:17

Timothy P. Durrett, Christoph Benning, John Ohlrogge, Plant triacylglycerols as feedstocks for the production of biofuels. The Plant Journal, Volume 54, Number 4, May 2008 , pp. 593-607(15)

Further Reading:
Biotechnology for Beginners by Reinhard Renneberg

Introduction to Biotechnology by William J. Thieman

Pharmaceutical Biotechnology: Fundamentals and Applications by Daan J. A. Crommelin

Copyright (c), 2008, jeepakistan.blogspot.com

Tuesday, May 13, 2008

Computer

Computers have made it possible to look into future of humanity. (Gerwin Schalk) The theoretical groundwork of the 1930s and 1940s and the technical advance of computers in the following decades provided the basis for dramatic increases in human efficiency. (Ning Fang et al.)Computer-assisted instruction is an innovative instructional strategy that has been receiving increasing attention in engineering and technology education.

(D. Wang et al.) The computer use information embedded in simple coding, the binary software code, to support system operations.In a computer, the software provides instructions and data for the CPU. A process represents just sequentially ordered actions by the CPU and virtual parallelism can be implemented through CPU time-sharing.

References:
Gerwin Schalk, Brain–computer symbiosis. Journal of Neural Engineering 5 , 2008, Pages 1-15.

Ning Fang, Gary A. Stewardson, Margaret M. Lubke, Enhancing Student Learning of an Undergraduate Manufacturing Course with Computer Simulations. International Journal of Engineering Education, Volume 24, Number 3, March 2008 , Pages 558-566.

D. Wang, M. Gribskov, Examining the architecture of cellular computing through a comparative study with a computer. Journal of the Royal Society, Interface/Royal Society. 2005 Jun 22;2(3): Pages 187-95.

Further Reading:
Discovering Computers 2009: Complete by Gary B. Shelly

Rule the Web: How to do Anything and Everythin on the Internet by Mark Frauenfelder

Shopping:
Computers and PC Hardware

Copyright (c) 2008, of jeepakistan.blogspot.com

Memory and Intelligence

For centuries man is trying to explore ways to enhance the memory performance. Several researches and studies are there.

Scientists (Vasudevan, Mani et al.) found that Thespesia populnea bark appears to be a promising candidate for improving memory, and it would be worthwhile to explore the potential of this plant in the management of Alzheimer patients. This bark is found in Indian region. Studies (P. T. Staff) indicate that ginkgo can help improve memory, concentration and mood. Ginkgo is recommended in a dose of 40 mg to 80 mg three times per day of an extract standardized to 24% flavonoid glycosides and 65% terpenoids. Expect to take the herb for at least eight weeks before seeing an improvement in memory.

(A.T. Frais) Omega-3 fish oil has been shown to improve memory. (Health News) Omega-3 might ease depression, enhance mind & memory. There's a growing body of evidence that DHA benefits gray matter, but it's not a cure-all, say researchers.

(P. T. Staff) Memory experts are now focusing on phosphatidyl-serine (PS), a naturally produced, fat-soluble nutrient. Found throughout our bodies, PS works particularly hard in the brain to improve brain cell communication and regulate serotonin and dopamine--both mood-related chemicals. Numerous studies have shown that people who take PS remember more names, faces, phone numbers and written information. And research conducted by Thomas Crook, Ph.D., founder of the Memory Assessment Clinic in Bethesda, Maryland, found that subjects who took 300 mg of PS for 90 days showed remarkable improvement in their memory. PS, according to Kidd, "can turn back the clock 12 to 15 years."


References:
A. T. Frais, Depression and the causal role of specific memory system degenerations: link may be supported by reported therapeutic benefits of Omega 3 fatty acids. Medical Hypotheses. 2007;69(1):Pages 67-9.

Health News. 2007 Jun;13(6): Pages 4-5.

ManiVasudevan, Milind Parle, Memory-Enhancing Activity of Thespesia populnea in Rats. Pharmaceutical Biology(Formerly International Journal of Pharmacognosy), Volume 45, Number 4, April 2007 , Pages 267-273.

P.T. Staff, Ginkgo: The Brain BoosterDiscusses the health benefits of ginkgo biloba. Anti-aging properties; Information on where researchers attribute ginkgo's effects; Recommended dosage. Psychology Today, Mar/Apr 99.

P. T. Staff, P.S. Don't Forget. Examines the effectiveness of phosphatidyl-serine (PS) to treat absent-mindedness. Mechanism of action; Role of PS in improving motor skills in Parkinson's disease patients. Psychology Today, Mar/Apr 2001.

Further Reading:
Double Your Brain Power: Increase Your Memory by Using All of Your Brain All the Time by Jean Marie Stine

Life's a Smelling Success: Using Scent to Empower Your Memory and Learning by Alan Hirsch

Your Memory : How It Works and How to Improve It by Kenneth L. Higbee

Copyright (c) 2008 of jeepakistan.blogspot.com.

Monday, May 12, 2008

Love

One of the most beautiful emotion of human beings is "Love".

Scientists (Gian C. Gonzaga et al.) have found that love serves a function distinct from desire and that love can operate as a commitment device. (Eva L. Wyss) Over the past two centuries concepts of love, as well as the nature of intimate relations, have undergone modifications. Along with these modifications, the language of desire, the text type of the love letter and love-letter writing practice have changed as well.

( Rachel Nowak) Romantic thoughts about a regular partner help to keep us from straying into illicit sexual liaisons. (Susan Sprecher) Love and related phenomena increases with time that is "I love you more today than yesterday". (Abraham Tesser et al.) In love thought about other and love for other have a positive causal impact on one another. Research ( L. L. Bachand et al.) shows that friendship, love and similar backgrounds or interests are most commoc factors for the longevity of a happy marriage.

References:
Abraham Tesser, Delroy L. Paulhus, Toward a causal model of love. Journal of Personality and Social Psychology Volume 34, Issue 6, December 1976, Pages 1095-1105.

Eva L. Wyss, Changes in text type from the nineteenth century to the Internet era. Journal of Historical Pragmatics, Volume 9, Number 2, 2008 , Pages 225-254.

Gian C. Gonzaga, Martie G. Haselton, Julie Smurda, Mari sian Davies and Joshua C. Poore. Love, desire, and the suppression of thoughts of romantic alternatives. Evolution and Human Behavior, Volume 29, Issue 2, March 2008, Pages 119-126.

L. L. Bachand, S. L. Caron, Ties that Bind: A Qualitative Study of Happy Long-Term Marriages. Contemporary Family Therapy, Volume 23, Number 1, March 2001 , Pages 105-121.

Rachel Nowak, Love will keep us together. The New Scientist, Volume 197, Issue 2648, 22 March 2008, Page 15.

Susan Sprecher, “I Love You More Today Than Yesterday”: Romantic Partners’ Perceptions of Changes in Love and Related Affect Over Time. Journal of Personality and Social Psychology, Volume 76, Issue 1, January 1999, Pages 46-53.

Further Reading:
The Science of Love by John Baines.

Science of Love: The Wisdom of Well-Being by Thomas Jay Oord.

A General Theory of Love by Thomas Lewis

Copyright (c) 2008 of jeepakistan.blogspot.com

Sunday, May 11, 2008

Power Generation

The scientists are increasingly finding ways to produce electricity in newer ways.

Fuel cell:

The commercialisation of fuel cells started in 2007, according to Fuel Cell Today in its 2008
Industry Review, released on 30th January. The Review, titled “Fuel Cells: Commercialisation”,
reports that in the last year the fuel cell industry has seen a growth of 75 per cent in new units
delivered, with some 12,000 new fuel cell units shipped during 2007.

Fuel Cell Today believes that the current global manufacturing capability for fuel cells is around 100,000 units per annum, with a quarter of this coming from companies whose business activity is exclusively the development of hydrogen and fuel cell technologies. The Fuel Cell Industry Review aims to provide a concise and accurate summary of worldwide fuel cell activity.

Alongside informationon legislation, finance, applications and key fuel cell companies, the Review publishes, for the first time, the Fuel Cell Today analysts’ forecasts of fuel cell shipments for the next two years. The forecasts include data by geographical region, fuel cell technology type and end use application. (1)

(Shucheng Sun et al.) Fuel cells for automobile application need to operate in a wide temperature range including freezing temperature.

(Chun wong et al.) The electrochemical activity of Glucose oxidase makes it an important component in glucose sensors and potentially in fuel cell applications.

Microbial Fuel Cell:
(Y. K. Cho et al.) Scientists working on solar-powered electricity generation by Rhodobacter sphaeroides in a single-chamber microbial fuel cell (MFC). They have shown that solar energy can serve as an alternative energy source for MFC operation. (Liping Huang et al.) Xylose can be used in the MFC for electricity production. Comparatively higher electricity generation and coulombic efficiency can be obtained by adjusting initial xylose concentration and applying stirring in the anode chamber.


References:
(1). Fuel Cell Today Industry Review 2008
“FUEL CELLS: COMMERCIALISATION”. Platinum Metals Review, Volume 52, Number 2, April 2008 , Pages.123-123.
Chun wong, Kwun Wong, Xiao Chen, Glucose oxidase: natural occurrence, function, properties and industrial applications. Applied Microbiology and Biotechnology, Volume 78, Number 6, April 2008 , Pages 927-938.
Liping Huang, Raymond J. Zenga and Irini Angelidaki. Electricity production from xylose using a mediator-less microbial fuel cell. Bioresource Technology, Volume 99, Issue 10, July 2008, Pages 4178-4184.
Shucheng Sun, Hongmei Yu, Junbo Hou, Zhigang Shao, Baolian Yi, Pingwen Ming and Zhongjun Hou. Catalytic hydrogen/oxygen reaction assisted the proton exchange membrane fuel cell (PEMFC) startup at subzero temperature. Journal of Power Sources, Volume 177, Issue 1, 15 February 2008, Pages 137-141
Y. K. Cho; T. J. Donohue; I. Tejedor; M. A. Anderson; K. D. McMahon; D. R. Noguera. Development of a solar-powered microbial fuel cell
Journal of Applied Microbiology, Volume 104, Number 3, March 2008 , Pages 640-650.

Friday, May 9, 2008

Mobile Devices

Cell phones are the most attractive technological products of this world. Infact in this fastly changing world of technology, cell phones are taking the positions of computers speedily.

(Mitchell Brown) Computer technology expanding into everyday life has ensured that gadgets play a significant role in our daily routines. We use them at work, home, and during leisure time. The gadgets range from smartphones, keyboards, headphones, media storage devices, and more. The range of materials, functionality, and application increases every quarter and changes can be seen in many different products.

Psychological Aspects:
(D. Avrahami et al.) A problem with the location-free nature of cell phones is that callers have difficulty predicting receivers' states, leading to inappropriate calls. One promising solution involves helping callers decide when to interrupt by providing them contextual information about receivers. Callers provided with contextual information made significantly more accurate decisions than those without it.

Medical Aspects:
(F. Deepinder et al.) There has been a tremendous increase in the use of mobile phones in the past decade and concerns are growing about the possible hazardous effects of radio-frequency electromagnetic waves (EMW) emitted by these devices on human health. A recent study found that use of cell phones adversely affects the quality of semen by decreasing the sperm counts, motility, viability and morphology.

Recently:
(F-L Tan et al.) Nowadays scientists are working on the Remote access of electronic resources for thermal plant using mobile devices.

In this case, the user enters the input through a Java MIDlet running on the mobile device. The inputs are then transferred to a Java Servlet running on a server to access the electronic resources. A case study on the computation of thermodynamic properties for steam and refrigerant on the server is demonstrated. The computed properties are transmitted back to the mobile device for display.

References:
1. Avrahami, D.1; Gergle, D.1; Hudson, S. E.1; Kiesler, S.1. Behaviour and Information Technology, Volume 26, Number 3, May 2007 , Pages 247-259(13). 1: Human-Computer Interaction Institute, Carnegie Mellon University, Pittsburgh, PA, USA .
2. F. Deepinder, K. Makker, A. Agarwal, Cell phones and male infertility: dissecting the relationship. Reprod Biomed Online. 2007 Sep;15(3):Pages 266-70.
3. F-L. Tan, S-C. Fok, Remote access of electronic resources for thermal plant using mobile devices. International Journal of Computer Applications in Technology, Volume 30, Number 4, 19 February 2008 , Pages 256-265.
4. Mitchell Brown, New Gadgets Worth Exploring. Library Hi Tech News incorporating Online and CD Notes, Volume 24, Number 8, 2007 , Pages 10-13.

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