bluuebunny/crossref_metadata_2025 huggingface dataset:
2007 Update on Allogeneic Islet Transplantation from the Collaborative Islet Transplant Registry (CITR)
Authors:   The CITR Research Group
Published: October 2009

As of October 1, 2007, 25 North American medical institutions and one European islet transplant center reported detailed information to the Registry on 315 allograft recipients, of which 285 were islet alone (IA) and 30 were islet after kidney (IAK). Of the 114 IA recipients expected at 4 years after their last infusion, 12% were insulin independent, 16% were insulin dependent with detectable C-peptide, 40% had no detectable C-peptide, and 32% had missing C-peptide data or were lost to follow-up. Of the IA recipients, 72% achieved insulin independence at least once over 3 years and multiple infusions. Factors associated with achievement of insulin independence included islet size >1.0 expressed as IEQs per islet number [hazard ratio (HR) = 1.5, p = 0.06], additional infusions given (HR = 1.5, p = 0.01), lower pretransplant HbA1c (HR = 1.2 each %-age unit, p = 0.02), donor given insulin (HR = 2, p = 0.003), daclizumab given at any infusion (HR = 1.9, p = 0.06), and shorter cold storage time (HR = 1.04, p = 0.03), mutually adjusted in a multivariate model. Severe hypoglycemia prevalence was reduced from 78–83% preinfusion to less than 5% throughout the first year post-last infusion, and to 18% adjusted for missing data at 3 years post-last infusion. In Year 1 post-first infusion for IA recipients, 53% experienced a Grade 3–5 or serious adverse event (AE) and 35% experienced a severe AE related to either an infusion procedure or immunosuppression. In Year 1 post-first infusion, 33% of IA subjects and 35% of IAK subjects had an AE related to the infusion procedure, while 35% of IA subjects and only 27% of IAK subjects had an AE related to the immunosuppression therapy. Five deaths were reported, of which two were classified as probably related to the infusion procedure or immunosuppression, and 10 cases of neoplasm, of which two were classified as probably related to the procedure or immunosuppression. Islet transplantation continues to show short-term benefits of insulin independence, normal or near normal HbA1c levels, and sustained marked decrease in hypoglycemic episodes.
Computer-Based Wireless Advertising Communication System
Authors: Khraisat Yahya Salameh , Al-Mofleh Anwar
Published: October 2009

In this paper we developed a computer based wireless advertising communication system (CBWACS) that enables the user to advertise whatever he wants from his own office to the screen in front of the customer via wireless communication system. This system consists of two PIC microcontrollers, transmitter, receiver, LCD, serial cable and antenna. The main advantages of the system are: the wireless structure and the system is less susceptible to noise and other interferences because it uses digital communication techniques.
Dynamic Resource Management in MC-CDMA Based Cellular Wireless Networks
Authors: Kumar Dhananjay , Chellappan Chenniappan , Vani Bala Jeevitha
Published: October 2009

Most of the multimedia and Internet services today are asymmetric in nature, and require high data rate support. Allocating equal band width in both uplink and downlink is not prudent solution, as most of the time user requirement is more either in uplink or downlink. The Multi Carrier Code Division Multiple Access (MC-CDMA) system with time division duplex mode can easily met this requirement by dynamically declaring traffic direction in TDD slot, and adaptively allocating the sub channels. In this paper, we propose a adaptive slot and sub carrier allocation algorithm, that can be independently implemented in each cell of mobile communication network. Our analytical model is generalization of two cell concept to represent a multi cell model. Based on two cell concept four cases of interference pattern has been considered and simulated separately in presence of Additive White Gaussian Noise (AWGN) and Rayleigh Channel. The simulated result suggests the requirement of approximately 9dB of Signal to Noise Ratio (SNR) to maintain Bit Error Rate below 10-3. We also analyze the average delay incurred by the proposed algorithm in allocating resources.
Robotic Mobile System's Performance-Based MIMO-OFDM Technology
Authors: Daoud Omar , Alani Omar
Published: October 2009

In this paper, a predistortion neural network (PDNN) architecture has been imposed to the Sniffer Mobile Robot (SNFRbot) that is based on spatial multiplexed wireless Orthogonal Frequency Division Multiplexing (OFDM) transmission technology. This proposal is used to improve the system performance by combating one of the main drawbacks that is encountered by OFDM technology; Peak-to-Average Power Ratio (PAPR). Simulation results show that using PDNN resulted in better PAPR performance than the previously published work that is based on linear coding, such as Low Density Parity Check (LDPC) codes and turbo encoding whether using flat fading channel or a Doppler spread channel.
Envelope Transaction Mechanism for A Cluster of Peers
Authors: Kulkarni Sushil T. , Sanglikar Mukund A.
Published: October 2009

A new approach for mobile transaction processing is presented in a cluster of peers. A cluster is a dynamic collection of mobile hosts called peers and are clustered around a single mobile host called a centroid to form a temporary work group for processing and exchanging information. All peers are connected to the centroid using a short range wireless network. All peers and the centroid are members of a peer connected set. The centroid is chosen in such a way that it has a strong connection to the mobile support station. After collecting data from a server, the centroid is free to disconnect from the server and ready to create its own cluster of peers. To process various transactions at the centroid, a dynamically configurable data processing space is created called the envelope repository. Processed data is kept at a private work space of the centroid in an envelope and brought to the envelope repository whenever required. A peer initiates a jumping transaction to fetch data objects to the centroid. The jumping transaction initiates an envelope transaction to acquire the necessary locks on data objects at envelope repository. After getting the locks, intension transaction processes the data objects to give the result stored in an envelope. Envelope intension write protocol is designed to make jumping transactions globally serialized.
Resource Optimization of Mobile Intelligent System with heart MPLS network
Authors: Oubaha Jawad , Habbani Ahmed , Elkoutbi Mohammed
Published: October 2009

In this paper, we introduce the original Mobile Intelligent System (MIS) in embeded FPGA architecture. This node will allow the construction of autonomous mobile network units which can move in unknowns, inaccessible or hostile environnement for human being, in order to collect data by various sensors and transmits them by routing to a unit of distant process.

In the sake of improving the performance of transmission, we propose a global schema of QoS management using DiffServ/MPLS backbones. We provide an evaluation of several scenarios for combining QoS IP networks with MIS access network. We conclude with a study on interoperability between QoS patterns in access and backbone networks.
Discrete Domains of MARCH1 Mediate Its Localization, Functional Interactions, and Posttranscriptional Control of Expression
Authors: Jabbour Maurice , Campbell Erin M. , Fares Hanna , Lybarger Lonnie
Published: October 2009

Within APCs, ubiquitination regulates the trafficking of immune modulators such as MHC class II and CD86 (B7.2) molecules. MARCH1 (membrane-associated RING-CH), a newly identified ubiquitin E3 ligase expressed in APCs, ubiquitinates MHC class II, thereby reducing its surface expression. Following LPS-induced maturation of dendritic cells, MARCH1 mRNA is down-regulated and MHC class II is redistributed to the cell surface from endosomal compartments. Here, we show that MARCH1 expression is also regulated at the posttranscriptional level. In primary dendritic cell and APC cell lines of murine origin, MARCH1 had a half-life of <30 min. MARCH1 degradation appears to occur partly in lysosomes, since inhibiting lysosomal activity stabilized MARCH1. Similar stabilization was observed when MARCH1-expressing cells were treated with cysteine protease inhibitors. Mutational analyses of MARCH1 defined discrete domains required for destabilization, proper localization, and functional interaction with substrates. Taken together, these data suggest that MARCH1 expression is regulated at a posttranscriptional level by trafficking within the endolysosomal pathway where MARCH1 is proteolyzed. The short half-life of MARCH1 permits very rapid changes in the levels of the protein in response to changes in the mRNA, resulting in efficient induction of Ag presentation once APCs receive maturational signals.
Anxiety levels in mothers of children with specific learning disability
Authors: Karande S , Kumbhare N , Kulkarni M , Shah N
Published: October 2009

Background:

Parents of children with specific learning disability (SpLD) undergo stress in coping with their child's condition.

Aim:

To measure the levels of anxiety and find out the cause of anxiety in mothers of children with SpLD at time of diagnosis.

Settings and Design:

Prospective rating-scale and interview-based study conducted in our clinic.

Materials and Methods:

One hundred mothers of children (70 boys, 30 girls) with SpLD were interviewed using the Hamilton anxiety rating scale (HAM-A) and a semi-structured questionnaire. Detailed clinical and demographic data of mothers were noted.

Statistical Analysis:

Chi-square test or unpaired student's t-test was applied wherever applicable.

Results:

The mean age of mothers was 40.14 years (±SD 4.94, range 25.07-54.0), 73% belonged to upper or upper middle socioeconomic strata of society, 67% were graduates or postgraduates, 58% were full-time home-makers, and 33% lived in joint families. Levels of anxiety were absent in 24%, mild in 75%, and moderate in 1% of mothers. Their mean total anxiety score was 5.65 (±SD 4.75, range 0-21), mean psychic anxiety score was 3.92 (±SD 3.11, range 0-13), and mean somatic anxiety score was 1.76 (±SD 2.05, range 0-10). Their common worries were related to child's poor school performance (95%), child's future (90%), child's behavior (51%), and visits to our clinic (31%).

Conclusion:

Most mothers of children with SpLD have already developed mild anxiety levels by the time this hidden disability is diagnosed. These anxieties should be addressed by counseling to ensure optimum rehabilitation of these children.
Prevalence of RET/PTC expression in papillary thyroid carcinoma and its correlation with prognostic factors in a north Indian population
Authors: Mishra A , Agrawal V , Krishnani N , Mishra SK
Published: October 2009

Context:

The prevalence of Rearranged during Transfection/Papillary Thyroid Carcinoma (RET/PTC) rearrangement in papillary thyroid carcinoma (PTC) varies in different geographic regions and its prognostic significance remains unclear.

Aim:

The aim of this study was to recognize the prevalence of RET/PTC expression in PTC from the endemically iodine-deficient region in Northern India and to correlate the expression with the clinicopathologic prognostic factors.

Settings and Design:

Retrospective. Archival tissue used.

Materials and Methods:

Immunohistochemistry was performed to look for activated RET protein expression in 50 cases of PTC. No patient had any history of prior irradiation. Statistical Analysis Used : Chi-square method, Student t test, and binary regression method. A P value of <. 05 was considered significant for all the tests.

Results:

The prevalence of RET expression was 44%. Twenty-six (52%) cases showed RET immunoreactivity in histiocytes. Immunoreactivity was the highest in the classic variant of PTC (47.5%), followed by tumors with poorly differentiated areas (25%) and follicular variant (16.7%). RET expression was more prevalent in young patients (45.5 vs. 35.3%), females (43.3 vs. 40.0%), small tumors (33.3 vs. 26.7%), multicentric tumors (36.8 vs. 33.3%), tumors with extrathyroidal invasion (38.9 vs. 32.4%), and regional lymphadenopathy (55.2 vs. 22.2%), while it was less in cases with distant metastases (20 vs. 43.9%). There was no significant correlation of immunoreactivity with any prognostic factor. However, when the cases having immunoreactivity within histiocytes (n=26) and histiocytes + tumor tissue (n=28) were considered, then the expression was significantly more in cases with lymphadenopathy (P values=.009, in both instances). However, the exact clinical significance of RET/PTC positive histiocytes remained unexplained.

Conclusions:

Prevalence of RET/PTC in our study was consistent with the reported prevalence from other geographic areas. There was no significant correlation with the clinicopathologic factors. However, uniform techniques of detection and large international collaborative studies could clear the uncertainties regarding the prognostic importance of RET/PTC.
Evaluation of intracranial space-occupying lesion with Tc99m-glucoheptonate brain single photon emission computed tomography in treatment-naïve patients
Authors: Jaiswal S , Barai S , Rajkumar  , Gambhir S , Ora M , Mahapatra AK
Published: October 2009

Background:

Glucoheptonate is a glucose analog with strong affinity for neoplastic brain tissues. Though extensively used as a tracer for detection of brain tumor recurrence, it's utility for characterization of intracranial lesions as neoplastic or otherwise has not been evaluated in treatment-naοve patients.

Aim:

The study was conducted to determine if glucoheptonate has sufficient specificity for neoplastic lesions of brain so that it can be utilized as a single photon emission computed tomography (SPECT)-tracer for differentiating neoplastic intracranial lesions from non-neoplastic ones in treatment-naοve patients.

Settings and Design:

A cross-sectional analysis of treatment-naοve patients with intracranial space-occupying lesion done in a tertiary care hospital.

Materials and Methods:

Fifty-four consecutive patients with clinical and radiological features of space-occupying lesion were included in this study. Glucoheptonate brain SPECT was performed before any definitive therapeutic intervention. Histopathological verification of diagnosis was obtained in all cases.

Statistical Analysis Used:

Descriptive statistics and student's 't' test.

Result:

Increased glucoheptonate uptake over the site of radiological lesion was noted in 41 patients and no uptake was noticed in 13 patients. Histopathology of 12 out of the 13 glucoheptonate non-avid lesions turned out to be non-neoplastic lesion; however, one lesion was reported as a Grade-2 astrocytoma. Histology from all the glucoheptonate concentrating lesions was of mitotic pathology. The sensitivity, specificity and accuracy of glucoheptonate for neoplastic lesion was 97.6%, 100% and 98.1%.

Conclusions:

Glucoheptonate has high degree of specificity for neoplastic tissues of brain and may be used as a tracer for SPECT study to differentiate neoplastic intracranial lesions from non-neoplastic ones.
Effect of amitriptyline vs. physiotherapy in management of fibromyalgia syndrome
Authors: Joshi MN , Joshi R , Jain AP
Published: October 2009

Context:

Fibromyalgia is a chronic disabling condition, and physicians treat it using a number of different treatment modalities. It is not known if one or more of such modalities are better than the others. We compared the efficacy of physiotherapy and amitriptyline in disability reduction in patients of fibromyalgia syndrome in a rural tertiary care hospital in Central India.

Design:

Open-label alternate patient treatment allocation.

Materials and Methods:

A six-month follow-up was done to assess the benefit of amitriptyline and physiotherapy for disability reduction in patients with fibromyalgia syndrome. Primary outcome measure was improvement in fibromyalgia impact questionnaire (FIQ) score.

Statistical Analysis Used:

Predictors of benefit were determined using multivariate logistic regression.

Results:

A total of 175 outpatients were assigned to either amitriptyline (n=87) or structured physiotherapy (n=88) treatments. There was a significant but similar (P=0.82) improvement in disability in both groups. High FIQ score at baseline and low socioeconomic status scores were significant predictors of benefit.

Conclusions:

Therapy with amitriptyline or physiotherapy is equally effective in improving outcome in patients of fibromyalgia over a period of six months.
Granulomatous cheilitis secondary to tuberculosis in a child
Authors: Bhattacharya M , Rajeshwari K , Sardana K , Gupta P
Published: October 2009

Granulomatous cheilitis is a chronic granulomatous inflammation of the lips that can be secondary to various etiologies. A few infectious agents including Mycobacterium tuberculosishave been implicated in its etiology. It can be the clinical presentation of a tuberculide resulting from a hypersensitivity reaction to an underlying focus of tuberculosis such as pulmonary tuberculosis.

This case report describes a child with granulomatous cheilitis with pulmonary tuberculosis, who responded to anti-tubercular treatment. This is probably the first pediatric case of this rare condition.
Tracheal necrosis with surgical emphysema following thyroidectomy
Authors: Chauhan A , Ganguly M , Saidha N , Gulia P
Published: October 2009

Tracheal necrosis after thyroidectomy is an extremely rare event with only a few published reports. We present a case of a 65-year-old male who developed rapidly progressive surgical emphysema of face and upper thorax on the seventh day following total thyroidectomy. Prompt surgical exploration of neck revealed a tracheal rent at the level of the second tracheal ring. This hole was then refashioned into a formal tracheostomy. Patient had an eventful recovery. Tracheostomy was closed by the 14th day. The complication was probably related to tracheal injury sustained due to electro-coagulation and subsequent secondary infection.
Patient-based not problem-based learning
Authors: Franklyn-Miller AD , Falvey EC , McCrory PR
Published: October 2009

Context:

There have been significant changes in the past decade in both the curriculum and its delivery, in undergraduate medical education. Many of these changes have been made simultaneously, preventing clear assessment of outcome measures. The move away from a pre-clinical science grounding, to an integrated 'problem-based learning (PBL) approach' has been widespread in many countries across the world.

Purpose:

One effect of these changes has been the way in which clinical skills, in particular history and examination are taught. By integrating clinical scenarios earlier in the undergraduate course, clinical skills are increasingly taught in tutorials. This approach, when used in the pre-clinical setting may have shortcomings in the development of the ability to construct a differential diagnosis. There has been little evidence that PBL improves problem-solving ability and this is critical to the differential diagnostic process. The concurrent decline in anatomical teaching and understanding contributes to this difficulty.

Discussion:

The authors outline a model which clinicians can re-emphasize to students and juniors based on the fundamentals of clinical practice. The apprenticeship is more important than ever in the days of small group learning. The relinquishing of the traditional model of undergraduate medicine is of concern. The effects of educational reform should be examined by further research into the competencies of graduates entering higher professional training, before it is accepted that this change has been for the better.
Treatment of leprosy in India
Authors: Gautam VP
Published: October 2009

Introduction of multi-drug therapy (MDT) into the National Leprosy Eradication Program (NLEP) of India has brought a decline in both the burden of the disease and the detection of new cases in the country. Despite this success, MDT has had many problems like remarkable relapse rate, non-adherence to the MDT and the emergence of drug resistance associated with it. Moreover, there is no new MDT regimen at present, which could solve all these problems. The current situation suggests that we should look for alternative solutions in the delivery of leprosy-related services. With the introduction of Accredited Social Health Activists under the National Rural Health Mission, there is an opportunity to control some of these problems associated with MDT. Besides, District Nucleus should take initiatives and actively participate in establishment of coordination between departments of Health, Social welfare and justice, education and various non-governmental agencies working in the field of leprosy and disability in order to deliver the best of services to the persons affected by leprosy.
Oseltamivir
Authors: Tullu MS
Published: October 2009

Oseltamivir, a selective neuraminidase enzyme inhibitor, has gained worldwide attention in view of Influenza A (H1N1) pandemic. It is one of the most important drugs effective against the novel influenza virus. Oseltamivir is used for the treatment of uncomplicated acute illness due to influenza infection. Early initiation of treatment with the drug provides greater clinical benefits. The drug can also be effectively used for prophylaxis. Oseltamivir is readily absorbed from the gastrointestinal tract and is converted to the active metabolite- oseltamivir carboxylate, which has a wider distribution in the body. Oseltamivir carboxylate is eliminated in the urine with a half-life of 6-10 h. The drug is generally well-tolerated and does not have many clinically significant drug interactions. Nausea and vomiting are the commonest adverse effects associated with its use. The standard adult dose for treatment is 75 mg twice a day for five days and the dose for prophylaxis is 75 mg once daily for at least seven days following contact with an infected individual. The dose needs to be adjusted in patients with renal failure but no adjustments are required in patients with hepatic impairment. Although most of the influenza virus strains are sensitive to oseltamivir, development of drug resistance may limit the clinical utility of the drug in the future.
Application of Single‐Cell Microfluorimetry to Neurotoxicology Assays
Authors: Limke Tobi L. , Atchison William D.
Published: November 2009

Intracellular signaling events play fundamental roles in regulating physiological function. In neurons, these include inducing growth and differentiation, secretion, gene expression, and controlling processes associated with learning and memory. All of these processes have in common the vital dependence on changes in intracellular Ca2+[Ca2+]i. Numerous toxicants, including metals, polychlorinated biphenyls, and biological neurotoxins, can disrupt [Ca2+]i. Understanding how toxicants disrupt Ca2+‐dependent neuronal signaling, and thus induce neuronal death or dysfunction, requires the ability to monitor [Ca2+]iat the level of individual cells. A series of fluorophores that can report on changes in [Ca2+]ihas been pivotal in this process. This section describes how to use these fluorophores to study effects of neurotoxicants on two types of processes: changes in [Ca2+]iin individual cells and changes in mitochondrial membrane potential. Similar techniques using distinct fluorophores can be applied to other physiological processes.Curr. Protoc. Toxicol. 42:12.15.1‐12.15.13. © 2009 by John Wiley & Sons, Inc.
Tellurium
Authors: Carapella S. C.
Published: November 2009

Uses

Chemistry and Compounds

Toxicity
Bacteria
Authors: DeBaldo Ann C.
Published: October 2009

Bacilli

Cocci

Curved or Bent Rods

Other Bases for Classifying Bacteria

Fundamental Structure of Bacteria

Disease‐Producing Bacteria

Remarkable Survivability of Some Bacteria

Prions

Beneficial Bacteria

Archaebacteria
Bovine Spongiform Encephalopathy (BSE)
Authors: Brown Paul , Will Robert G. , Bradley Raymond , Asher David M. , Detwiler Linda
Published: October 2009

VariantCreutzfeldt‐Jakob DiseasevCJD
Chronic Fatigue Syndrome (
CFS
)
Authors:   Centers for Disease Control and Prevention (CDC)
Published: October 2009

Is
CFS
Contagious?

Possible Causes of
CFS

Diagnosis of
CFS

Terms Most Often Encountered in Relation to
CFS
Common Cold
Authors:   National Institutes of Health
Published: October 2009

Cold Symptoms

How Cold Viruses Cause Disease

How Colds are Spread

Prevention

Treatment
Detergents
Authors: Venegas Manual G. , Kaminsky George J.
Published: October 2009

Detergent Ingredients and Their Functions

Types of Detergent Products
Digital‐to‐Analog Converter
Authors: Harrison Thomas J.
Published: October 2009

Decoding Networks
Electrical Ground Fault Circuit Interrupters (
GFCI
)
Authors: Douglas Jim
Published: October 2009

Ground Faults
Electroluminescent Displays
Authors:   Stanford Resources, Inc.
Published: October 2009

AC Thin‐Film Electroluminescent Displays

Active Matrix Thin‐Film Electroluminescent Displays

Hybrid Electroluminescent Displays

DC
Powder Electroluminescent Displays

Transparent Electroluminescent Displays
Geriatrics
Authors: Flurkey Kevin
Published: October 2009

The Relationship of Normative Aging to Geriatrics

Age‐Related Disorders

Incontinence

Dementia

Sleep Disorders

Digestive System Disorders

Gait Disorders of the Elderly

Special Problems with Diagnosis in the Elderly

Life Style Considerations
Gold
Authors: Corrigan Donald A.
Published: October 2009

Occurrence and Processing

Uses of Gold

Chemistry of Gold
Biofilms
Authors: Flemming Hans‐Curt
Published: October 2009

Most microorganisms on earth live in aggregates such as films, flocs, mats, granules or sludge – this form of life is referred to as ‘biofilms’, and it is involved in the biogeochemical cycles of all major elements including metals. Encased in a highly hydrophilic matrix of extracellular polymeric substances, biofilm organisms can develop stable microconsortia and complex interactions, resulting in features of multicellular organisms.
Anamorphic Fungi
Authors: Gams Walter , Seifert Keith A
Published: October 2009

The anamorphic fungi are an artificial assemblage of asexual stages of ascomycetes and basidiomycetes. They are classified together with asexually reproducing fungi that lack sexual structures. In this article, we review the classification and morphology of these moulds, and comment on their biology.
Archaeal Flagella
Authors: VanDyke David J , Ng Sandy Y M , Chaban Bonnie , Wu John , Jarrell Ken F
Published: October 2009

The archaeal flagellum is a unique, ‘tail‐like’ structure used for motility by single‐celled organisms belonging to the domain Archaea. These intricate protein assemblies extend from the cell surface, rotating to generate thrust that propels the organism. Although archaeal flagella are functionally similar to the flagella found on bacteria, they differ significantly in structure and presumed mode of assembly.

Key concepts

The student will learn:

Although functionally similar to bacterial flagella, archaeal flagella are unique motility structures in terms of their structure and assembly.

The structure of the flagellum can be divided into three distinct components: the filament, hook and anchoring structure. Each of these components is constructed of specific proteins either encoded by genes residing within flagellar operons or of currently unknown genes.

Assembly of the archaeal flagellum, which lacks the internal channel found in bacterial flagella, is thus believed to occur via incorporation of protein subunits at the base of the structure after they undergo the necessary posttranslational modifications of signal peptide cleavage and glycan addition.

Archaea use this motility apparatus in combination with chemotaxis systems to bias their direction of movement towards environmental conditions more favourable for cell growth.
Antiviral Drugs
Authors: Oxford John S
Published: October 2009

Antiviral drugs have now been developed against influenza, herpes, human immunodeficiency viruses, hepatitis C and hepatitis B. Drug resistance is a practical problem and is stimulating the wider search for new drugs using compound libraries, molecular technology and particularly X‐ray crystallography whilst drug combinations are used in acquired immune deficiency syndrome (AIDS) patients and hepatitis to reduce the opportunities for virus mutations. The threat of a global outbreak of chicken influenza (H5N1) has led to government stockpiling of the new antiflu drugs, the neuraminidase inhibitors. Pegylated and other interferons are used in drug combinations with hepatitis B and C patients.
Cyanobacteria
Authors: Palinska Katarzyna A
Published: October 2009

Cyanobacteria is a widely distributed group of unicellular and multicellular photosynthetic bacteria that possess chlorophyll
a
(Prochlorales additionally possess chlorophyll
b
) and perform oxygenic photosynthesis.
Bacterial Plasmids
Authors: Thomas Christopher M , Summers David
Published: October 2009

Plasmids are nonessential genetic elements that can maintain accessory genetic information and facilitate infectious spread of the genes they carry. They regulate their own replication and transmission and were largely responsible for the proliferation of antibiotic resistance during the second half of the twentieth century.
Bacteriophages in Industry
Authors: Callanan Michael J , Klaenhammer Todd R
Published: October 2009

Traditionally, bacteriophages (phages) have been regarded as a nuisance in industrial processes that rely on bacterial fermentation. In particular, the dairy industry has struggled with phage‐induced fermentation failure in the production of fermented food products. Phages attack the bacteria and slow or stop the fermentation process, resulting in reduced product quality and considerable financial loss. Significant effort has been dedicated by the dairy industry to combating phage infection. However, phage research has provided the molecular insight and tools required to exploit biological systems. This ability has provided the platform for the current expansion in biotechnology‐based industries.
Neural Tube Defects
Authors: Copp Andrew J
Published: October 2009

Neural tube defects (NTDs) are congenital malformations of the central nervous system and axial skeleton that range from the fatal to the asymptomatic. NTDs can be classified according to the embryonic event that is disturbed, and can result from a variety of genetic defects and environmental influences. Understanding the genetic and embryonic basis of NTDs is revealing the underlying developmental mechanisms, and enabling new approaches towards prevention of these serious birth defects. This strategy is exemplified by the ability of folic acid and other small molecules to prevent spina bifida.
Universal Genetic Code and its Natural Variations
Authors: Watanabe Kimitsuna , Suzuki Tsutomu
Published: October 2009

The universal genetic code is a common language for almost all organisms to translate nucleotide sequences ofdeoxyribonucleic acid(DNA) andribonucleic acid(RNA) to amino acid sequences of proteins. However, the genetic code is still evolved. Nonuniversal genetic codes are found in some organisms and organelles.Aminoacyl‐transfer RNA (tRNA) synthetasesand RNA modifications play a critical role in reassignment of the genetic code.
Somatic Hypermutation in Antibody Evolution
Authors: Longerich Simonne , Storb Ursula
Published: October 2009

Somatic hypermutation (SHM) of immunoglobulin (
Ig
) genes is a major mechanism for amplifying the antibody repertoire of vertebrates. SHM results in high frequencies of point mutations in the variable region of
Ig
genes, the region encoding the antigen‐binding domain of antibodies. The constant region is spared, ensuring conservation of the biological functions of antibodies. We briefly review the biology of SHM and its molecular hallmarks. We discuss what is known and what remains to be investigated of the molecular process that creates the mutations, including the properties, normal and aberrant functions of the activation induced deoxy‐cytidine deaminase, AID, the enzyme that initiates SHM.
Immunotoxicology
Authors: Luster Michael I , Simeonova Petia P , Germolec Dori R
Published: October 2009

Immunotoxicology can be defined as the study of adverse effects on the immune system resulting from exposure to physical factors (e.g. ionizing an ultraviolet radiation), chemicals (including drugs), biological materials, medical devices and, in certain instances, physiological factors, collectively referred to as agents. It encompasses studies of various immune pathologies associated with exposure of humans and wildlife species, including allergy, immune dysregulation (suppression or enhancement), autoimmunity and chronic inflammation.
Immunosuppression: Use in Transplantation
Authors: Prabhakaran Sangeetha , Humar Abhinav , Matas Arthur J
Published: October 2009

Clinical immunosuppression is the reduction of undesirable immunologic activity, usually achieved using immunosuppressive drugs. It is used in a variety of medical conditions, including inflammatory diseases and autoimmune disorders, but its most common application is in the field of organ transplantation.
Complement Regulatory Proteins
Authors: Meri Seppo , Jarva Hanna
Published: October 2009

An introduction to major fluid‐phase and membrane‐bound regulators of the complement system. Also, the most important diseases associated with complement regulator deficiencies and polymorphisms are described.
Human Evolution: Radiations in the Last 300 000 Years
Authors: Pearson Osbjorn M
Published: October 2009

Homo sapiens

and Neanderthals (

Homo neanderthalensis

) evolved from

Homo heidelbergensis

in the last 300 000 years.

H. sapiens

subsequently spread throughout the world; all other hominins disappeared. The Out of Africa and multiregional models offer different explanations for this pattern.
Mutational Biases
Authors: Yampolsky Lev Y , Stoltzfus Arlin
Published: October 2009

Mutational biases refer to systematic asymmetries or nonuniformities in the occurrence of mutations, heritable changes that take place in an individual organism. Mutational biases arise by asymmetries in damage, repair and replication of the genetic material. Many such biases are known: familiar examples include transition:transversion bias, the CpG effect and deletion:insertion bias. Mutation biases are biologically significant to the extent that they modulate the probabilities of heritable diseases and of evolutionary changes.
Human Population Genetics: Drift and Migration
Authors: Chakraborty Ranajit
Published: October 2009

Genetic drift is the effect of changes in genetic composition of a finite population, due to random replacement of alleles from one generation to the next. Migration effect specifies alterations caused by exchange of genes between populations.
Molecular Evolution: Nearly Neutral Theory
Authors: Ohta Tomoko
Published: October 2009

Nearly neutral theory is an extension of the neutral theory and contends that the borderline mutations, whose effects lie between the selected and the neutral classes, are important at the molecular level.
Mammalian Sex Determination
Authors: Simpson Joe Leigh
Published: October 2009

Sex determination is the process by which genes direct male and female embryos to become distinguishable from each other.
Claude Bernard
Authors: Gelfand Toby
Published: October 2009

The nineteenth‐century French physiologist whose animal experiments on digestion, neurophysiology and metabolism led to fundamental insights in general physiology. His concept of the ‘internal environment’ was based on the experimental demonstration of various mechanisms by which warm‐blooded animals maintained equilibrium conditions necessary for life. Although trained as a physician, Bernard's working career was spent in laboratory research and teaching at the Paris Collège de France. He believed the understanding of disease and ultimately clinical medical practice depended on the elucidation of fixed or deterministic laws of body function. His discoveries and conceptual contributions, along with his championing the discipline of physiology in France, made him the leading medical scientist of his period. His
Introduction to the study of experimental medicine
(1865) remained a classic text of methodology in the life sciences.
Boveri, Theodor
Authors: Dröscher Ariane
Published: October 2009

German zoologist (1862–1915) who pioneered experimental embryology proposed what was later called the chromosomal theory of heredity and correlated it with Mendel's laws. He likewise anticipated the idea of gradients in embryo cells and of uncontrolled cell division as a cause of cancer.
Baer, Karl Ernst von
Authors: Schmitt Stéphane
Published: October 2009

KE von Baer was one of the most important embryologists of the nineteenth century. In particular, he discovered the mammal egg (1821) and established that the embryonic development was gradual and not the simple growth of a preformed individual (1828).
Naegeli,
CW
von
Authors: Dröscher Ariane
Published: October 2009

Naegeli (1817–1891), a Swiss botanist, made numerous important cytological discoveries and developed new theoretical concepts of cellular constitution. His anti‐Darwinian orthogenetic theory enjoyed great success among German‐speaking botanists.
Weismann, August Friedrich Leopold
Authors: Dröscher Ariane
Published: October 2009

Weismann (1834–1914), a German zoologist who made important conceptual contributions to evolutionary theory and to heredity theory.
Remak, Robert
Authors: Dröscher Ariane
Published: October 2009

Remak (1815–1865), a Polish‐Prussian physician who made pioneering, though mostly neglected, discoveries in the fields of neurohistology, embryology, cell division, cellular pathology and electrotherapy.
Golgi: Methods for Preparation
Authors: Wang Yanzhuang
Published: October 2009

The Golgi apparatus can be purified from cells and tissues using a number of different methods, depending on the purpose for which it is to be used. Purified Golgi membranes have been used in a variety of cell‐free assays to investigate sugar modifications, vesicle transport, structural formation of the Golgi apparatus and the interaction of the Golgi with microtubules.
Von Frisch, Karl
Authors: Munz Tania
Published: October 2009

Karl von Frisch (1886–1982), an Austrian‐born scientist who discovered the meaning of the dance language by which honeybees communicate the location of foods and nesting sites to hive mates. He won the 1973 Nobel Prize in Physiology or Medicine together with the animal behaviourists Konrad Lorenz (also from Austria) and Nikolaas Tinbergen (of the Netherlands).
History of Clinical Medicine
Authors: Weatherall DJ
Published: October 2009

The history of clinical medicine reflects the slow evolution of the application of the biological sciences to the control and management of human disease. However, despite the remarkable advances in these fields in the latter half of the twentieth century, because of the multilayered complexities of disease processes and the ever changing environments of sick people, clinical medicine still remains very much a mix of applied science and the art of healing.
Meta‐analysis in Ecology
Authors: Hillebrand H
Published: October 2009

The synthesis of information across studies and ecosystems is highly important in ecological research. Meta‐analyses provide the statistical tools to quantitatively summarize the results of many empirical studies, comprising both the effects of experimental treatments and the correlation between observational data.
Scientific Method and Experimentation in Biology
Authors: Ruse Michael
Published: October 2009

Scientific method in biology has been of great interest since the time of the Greek philosopher Aristotle in the fourth century Before the Common Era. Generally, the aim has been to be like the physical sciences in being causal and increasingly showing biology as a topic governed by universal natural laws. However, there has always been a debate about the end directed nature of organisms, which seem to require explanations in terms of final causes. Although these were expelled from the physical sciences in the Scientific Revolution, they remained in biology until Darwin wrote the
Origin of Species
. Even after that, they remained but today can be seen to be natural and brought on by Darwin's mechanism of natural selection.
Bioethics of New Assisted Reproduction
Authors: Purdy Laura
Published: October 2009

New methods of assisted reproduction such asin vitrofertilization and intracytoplasmic sperm injection raise important moral issues. These include informed consent and a variety of consequentialist and structural concerns.
Hales, Stephen
Authors: Power Helen J
Published: October 2009

Stephen Hales (1677–1761), clergyman and natural philosopher, whose experimental investigations of plant and animal physiology and pneumatic chemistry made significant contributions in these fields.
Archaeal Genomes
Authors: Atlas Ronald M , Drell Daniel , Fraser‐Liggett Claire
Published: October 2009

The genomes of 46 archaeal species have been fully sequenced and published. As of this writing (September, 2007), 60 more are in various stages of progress. Analyses of these genomes are providing many useful insights into the evolution and functioning of diverse archaea, helping to understand the diverse physiological properties of archaea and their relationships to bacteria and eukarya.
Genome Organization of Vertebrates
Authors: Bernardi Giorgio
Published: October 2009

Compositional genomics, an approach relying on the base composition of genomes, helped to solve a long‐standing problem, namely the sequence organization of vertebrate and, more generally, of eukaryotic genomes.
Telomeric and Subtelomeric Repeat Sequences
Authors: Churikov Dmitri , Price Carolyn M
Published: October 2009

Telomeric repeats are the tandem arrays of a short G‐rich sequence that are present at the ends of most eukaryotic chromosomes. Subtelomeric sequences lie immediately proximal to the telomeric repeats and are composed of complex patchwork of low‐copy repeated sequences, segmental duplications and degenerate telomeric repeats.
Genetic Code: Evolution
Authors: Trifonov Edward N
Published: October 2009

‘Genetic code’ is the common name for the
ribonucleic acid
(RNA)–protein translation (
triplet
) code, one of many different codes harboured by the genomic sequences. This code was the first to be deciphered, is the best studied and is considered to be the major code.
Mitochondrial Genome: Evolution
Authors: Stoneking Mark
Published: October 2009

Mitochondria, organelles that are responsible for producing energy for cell metabolism and are also involved in cell death and aging, contain their own genome. This genome has several unusual properties, including a high copy number, a maternal and haploid mode of inheritance and a rapid rate of evolution, that make it of particular interest for reconstructing human evolution.
Human Genetic Diversity
Authors: Jorde Lynn B
Published: October 2009

Genetic diversity within and between human populations is being studied extensively. The results of these studies can be applied to questions about human evolutionary history, forensics and gene identification.
Phylogenetic Footprinting
Authors: Wasserman Wyeth W , Alkema Wynand
Published: October 2009

Phylogenetic footprinting is a method for the comparative analysis of orthologous gene sequences. Based on the expectation that sequences under selective pressure will be conserved over moderate periods of evolutionary time, phylogenetic footprinting is one means to identify gene segments with a specific function.
Gene Fusion
Authors: Betrán Esther
Published: October 2009

Gene fusion is a process by which the whole or parts of two or more distinct genes are juxtaposed and fused into a single gene. Often, a new gene and function can originate in this way. This phenomenon has been broadly observed in organisms ranging from higher eukaryotes to prokaryotes. Recent gene fusions reveal the mechanisms behind this phenomenon. Genome studies reveal the high and incessant incidence of gene fusions in genome evolution.
GC‐rich Isochores in the Interphase Nucleus
Authors: Saccone Salvatore , Bernardi Giorgio
Published: October 2009

In the interphase nuclei of human and other warm‐blooded vertebrates, the gene‐richest chromosomal regions are located in more internal positions and display much more spread‐out conformations than the gene‐poorest regions, the latter also showing more peripheral nuclear locations.
Gene Families: Formation and Evolution
Authors: Ohta Tomoko
Published: October 2009

A gene family is a set of genes derived by duplication of an ancestral gene. Various gene families, from small to large and from uniform to diverse, reflect effects of natural selection, random genetic drift and molecular mechanisms of gene duplication.
Evolution of Human Retrosequences: Alu
Authors: Roy‐Engel Astrid M , Batzer Mark A , Deininger Prescott L
Published: October 2009

Throughout evolution, mobile elements have accumulated to high copy numbers contributing to almost half of the human genomic mass. Evidence indicates that only the retroelements are currently active. In humans, the short interspersed elements (SINE), Alu, with over one million copies, outnumbers any of the other types of retroelements. Alu arose from the dimerization of modified 7SL RNA (ribonucleic acid) pseudogenes early in primate evolution, where different subfamilies continued to amplify during particular periods. Alu amplification has both positively and negatively impacted the human genome, and continues to play an important role in its shaping as a contributor of genetic instability and variation.
Phylogenetics
Authors: Li Wen‐Hsiung
Published: October 2009

Phylogenetics concerns the development of methods for reconstructing evolutionary relationships among organisms and the application of such methods to reconstruct phylogenetic trees using morphological or molecular data.
Hominids: Molecular Phylogenetics
Authors: Arnason Ulfur , Kullberg Morgan
Published: October 2009

Molecular relationships among the great apes (including

Homo

) and molecular estimates of the times of their divergences.
Genetic Information Access, a Legal Perspective: A Duty to Know or a Right Not to Know, and a Duty or Option to Warn?
Authors: Lemmens Trudo , Luther Lori , Hoy Michael
Published: October 2009

It is often argued that concern with basic personal privacy suggests that individuals should be allowed to decide in isolation whether to obtain genetic information through testing and whether to make the results available to others. However, the familial nature of genetic information complicates matters by raising question regarding whether an individual has a moral duty to discover and/or reveal existing genetic information to possibly affected family members. Alternatively, if this information would harm family members, do individuals have a duty not to obtain, or at least not to divulge, genetic test results? What role, if any, should legislation play in dealing with access to genetic information at the familial level? Do health care professionals have a responsibility or a right to inform close family members of the genetic status of a related individual? We consider the personal, familial and public health care perspectives regarding this debate.
Substitution Matrices
Authors: Altschul Stephen F
Published: October 2009

A substitution matrix is a collection of scores for aligning nucleotides or amino acids with one another. These scores generally represent the relative ease with which one nucleotide or amino acid may mutate into or substitute for another, and they are used to measure similarity in sequence alignments.
Comparative Human Genomics
Authors: Jordan I King , Koonin Eugene V
Published: October 2009

Comparative genomics involves the comparison of features of completely sequenced (or nearly so) genomes. Comparative sequence analyses facilitate both the functional annotation of genomes and whole‐genome approaches to evolutionary issues. We present a review of the field of comparative genomics and point out how the comparative approach can be used to help better understand the human genome sequence.