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The first radiation accident in America: a centennial account of the x-ray photograph made in 1890.

On February 22, 1890, Dr Arthur Goodspeed and William Jennings made the first x-ray photograph, in the physical lecture room of the University of Pennsylvania. On that evening, Goodspeed and Jennings had been making brush electrographs of coins and brass weights. After they finished their experiments, Jennings stacked all of the photographic plates; two coins--either left from the experiments or Jennings' trolley fare--were placed on top of the plates. Goodspeed then demonstrated to Jennings the university's collection of Crookes tubes, with the idea of photographing the glow from the tube. While the two men were talking, however, the Crookes tube was emitting x radiation that affected the nearby plates. After the plates were developed, Jennings noted that one had the shawdow(s) of a disk(s) on it; neither man could explain the image. On hearing of Roentgen's work in 1896, Goodspeed and Jennigns retrieved the original plate and reproduced their "accident." The glass plate was subsequently lost among library archives.

History, 19th Century↗

Patents and patent office resources in biotechnology.

Patents play an increasingly important role in the dissemination of information in many fast moving fields such as biotechnology and semiconductors. Quite a few new developments are introduced as patents, and only later, if at all, do they find their way into the scientific literature. In spite of this, patents lack wide acceptance as a source of information among scientists in academia and, to a lesser degree, industry. Patents share many similarities with scientific papers. They both are organized in a similar way and are carefully reviewed by experts in the field. Both can be effective and timely sources of information. Patents can be accessed through data bases, library collections, the "Official Gazette of the Patent and Trademark Office," or directly in the Patent and Trademark Office. This article is designed to serve as a guide to the type of information which can be found in patents, and alternatives for obtaining this information.

Biotechnology↗

Research: the third dimension of librarianship.

The rapid accumulation of data through increasingly sophisticated computer technology has created an unprecedented information explosion which might better be called an ignorance explosion. Data gathering emphasizing quantity rather than quality, speed of transmission rather than reliability or relevance, poses a challenge to the future of librarianship. Two concerns are discussed: (1) Relationship of technology to the information age. Librarians must be concerned with the methodology used in data collection, including the value judgments reflected in this activity. (2) Preparation of medical librarianship for the future. The profession will grow only as a result of individual effort, the recognition of people, and an appreciation of human values. Thus far, attempts to evaluate needs focus on technology while neglecting research into the human aspect. The author proposes that dimensions of the total professional model for medical librarianship must include research, as well as education and practice. The need to aid in the development of library researchers at the Ph.D. level through a National Library of Medicine program similar to that offered to researchers by the National Institutes of Health is stressed. By way of federal assistance and scholarships made available through national library associations, library research can become the vital and effective third dimension that will redefine the traditional concept of information storage and service in human terms, thus introducing a new relevance into the area of medical librarianship during the coming decades.

Library Schools↗

Doxapram versus methylxanthine for apnea in preterm infants.

BACKGROUND: Recurrent apnea is common in preterm infants, particularly at very early gestational ages. These episodes of loss of effective breathing can lead to hypoxemia and bradycardia which may be severe enough to require resuscitation including use of positive pressure ventilation. Doxapram and methylxanthine drugs have been used to stimulate breathing and so prevent apnea and its consequences. OBJECTIVES: In preterm infants with recurrent apnea, how does treatment with doxapram compare with treatment with theophylline in leading to a clinically important reduction in apnea and use of mechanical ventilation, without clinically important side effects. SEARCH STRATEGY: The standard search strategy of the Neonatal Review Group, as outlined in the Cochrane Library, was used. SELECTION CRITERIA: All trials utilising random or quasi-random patient allocation, in which doxapram was compared with methylxanthine (e.g. theophylline) for the treatment of apnea, were eligible. There must have been an effort to exclude specific causes of apnea. DATA COLLECTION AND ANALYSIS: The standard methods of the Cochrane Collaboration and its Neonatal Review Group were used to select trials, assess quality and to extract and synthesize data. The methodological quality of each trial was reviewed by the second author blinded to trial authors and institution(s). Additional information was requested from authors to clarify methodology. Each author extracted the data separately, then they were compared and differences resolved. Meta-analysis was carried out with use of relative risk and risk difference. MAIN RESULTS: In these trials involving a relatively small number of preterm infants with apnea of prematurity, there is no apparent difference between the effect of intravenous treatment with doxapram or methylxanthine on the incidence of apnea within 48 hours. There were no infants reported to have been given mechanical ventilation on either treatment. No adverse effects were reported. REVIEWER'S CONCLUSIONS: Implications for practice. The overall results of these small trials suggest that intravenous doxapram and intravenous methylxanthine are not different in their effectiveness in the short term in the treatment of apnea of prematurity. Caution is warranted as the number of patients in these trials is too small to exclude an important difference between these two treatments or to exclude the possibility of less common side effects. Longer term outcome of infants treated in these trials has not been reported. Implications for research. Further studies would require a large number of infants, stratified by gestation, to clarify which infants are likely to benefit and whether there might be differences in responses or side effects with these two drugs at different ages. It would be valuable to include important clinical outcomes such as use of mechanical ventilation as well as subsequent growth and development in future studies. Responses to treatment would have to take account of co-interventions, such as nasal continuous airway pressure which is frequently used post-intubation.

Aminophylline↗

Iron therapy for improving psychomotor development and cognitive function in children under the age of three with iron deficiency anaemia.

BACKGROUND: Iron deficiency and iron deficiency anaemia (IDA) are common in young children. It has been suggested that the lack of iron may have important effects on children's psychomotor development and cognitive function. OBJECTIVES: To determine the effects of iron therapy on psychomotor development and cognitive function in iron deficient children less than 3 years of age. SEARCH STRATEGY: The following databases were searched: COCHRANE LIBRARY (2000 ISSUE 4) MEDLINE (1966-August 2000) EMBASE (1980-August 2000) Latin American Database (LILACS) PsycLIT Journal articles (1974-August 2000) PsycLIT Chapters and Books (1987-August 2000) The references of identified trials and of important review articles were scrutinised. Citation searches on trials from the primary search were performed within the Science Citation Index. Key authors were contacted. SELECTION CRITERIA: Studies were included if children less than 3 years of age with evidence of iron deficiency anaemia were randomly allocated to iron or iron and vitamin C versus a placebo or vitamin C alone and assessment of developmental status or cognitive function was carried out using standardised tests by observers blind to treatment allocation. DATA COLLECTION AND ANALYSIS: Abstracts and titles of studies identified on searches of electronic databases were read to determine whether they might meet the inclusion criteria. Full copies of those possibly meeting these criteria from electronic or other searches were assessed by two independent reviewers. Differences of opinion about suitability for inclusion were resolved by discussion. Data were analysed separately depending on whether participants had iron assessments were performed within one month of beginning iron therapy or later. MAIN RESULTS: Five trials, including 180 children with IDA, examined the effects of iron therapy on measures of psychomotor development between 5 and 11 days of commencement of therapy. Data from four trials could be pooled. The pooled difference in pre to post treatment change in Bayley Scale PDI between iron treated and placebo groups was -3.2 (95%CI -7.24, 0.85) and in Bayley Scale MDI, 0.55 (95% CI -2.84, 1.75). Two studies, including 160 randomised children with IDA, examined the effects of iron therapy on measures of psychomotor development more than 30 days after commencement of therapy. Aukett et al reported the mean number of skills gained after two months of iron therapy, using the Denver test. The intervention group gained 0.8 (95% CI -0.18, 1.78) more skills on average than the control group. Idjrandinata et al reported that the difference in pre to post treatment change in Bayley Scale PDI between iron treated and placebo groups after 4 months was 18.40 (95%CI 10.16, 26.64) and in Bayley Scale MDI, 18.80 (95% CI 10.19, 27.41). REVIEWER'S CONCLUSIONS: There is no convincing evidence that iron treatment of young children with IDA has an effect on psychomotor development discernable within 5-11 days. The effect of longer term treatment remains unclear but the data would be compatible with clinically significant benefit. There is urgent need for further randomised controlled trials with long term follow up.

Anemia, Iron-Deficiency↗

Grommets (ventilation tubes) for hearing loss associated with otitis media with effusion in children.

BACKGROUND: Otitis media with effusion (OME), or 'glue ear', is very common in children, especially between the ages of one and three years with a prevalence of 10% to 30% and a cumulative incidence of 80% at the age of four years. OME is defined as middle ear effusion without signs or symptoms of an acute infection. OME may occur as a primary disorder or as a sequel to acute otitis media. The functional effect of OME is a conductive hearing level of about 25 to 30 dB associated with fluid in the middle ear. Both the high incidence and the high rate of spontaneous resolution suggest that the presence of OME is a natural phenomenon, its presence at some stage in childhood being a normal finding. Notwithstanding this, some children with OME may go on to develop chronic otitis media with structural changes (tympanic membrane retraction pockets, erosion of portions of the ossicular chain and cholesteatoma), language delays and behavioural problems. It remains uncertain whether or not any of these findings are direct consequences of OME. The most common medical treatment options include the use of decongestants, mucolytics, steroids, antihistamines and antibiotics. The effectiveness of these therapies has not been established. Surgical treatment options include grommet (ventilation or tympanostomy tube) insertion, adenoidectomy or both. Opinions regarding the risks and benefits of grommet insertion vary greatly. The management of OME therefore remains controversial. OBJECTIVES: To assess the effectiveness of grommet insertion compared with myringotomy or non-surgical treatment in children with OME. The outcomes studied were (i) hearing level, (ii) duration of middle ear effusion, (iii) well-being (quality of life) and (iv) prevention of developmental sequelae possibly attributable to the hearing loss (for example, impairment in impressive and expressive language development (measured using standardised tests), verbal intelligence, and behaviour). SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2003), MEDLINE (1966 to 2003), EMBASE (1973 to 2003) and reference lists of all identified studies. The date of the last systematic search was March 2003, and personal non-systematic searches have been performed up to August 2004. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating the effect of grommets on hearing, duration of effusion, development of language, cognition, behaviour or quality of life. Only studies using common types of grommets (mean function time of 6 to 12 months) were included. DATA COLLECTION AND ANALYSIS: Data from studies were extracted by two reviewers and checked by the other reviewers. MAIN RESULTS: Children treated with grommets spent 32% less time (95% confidence interval (CI) 17% to 48%) with effusion during the first year of follow-up. Treatment with grommets improved hearing levels, especially during the first six months. In the randomised controlled trials that studied the effect of grommet insertion alone, the mean hearing levels improved by around 9 dB (95% CI 4 dB to 14 dB) after the first six months, and 6 dB (95% CI 3 dB to 9 dB) after 12 months. In the randomised controlled trials that studied the combined effect of grommets and adenoidectomy, the additional effect of the grommets on hearing levels was improvement by 3 to 4 dB (95% CI 2 dB to 5 dB) at six months and about 1 to 2 dB (95% CI 0 dB to 3 dB) at 12 months. Ears treated with grommets had an additional risk for tympanosclerosis of 0.33 (95% CI 0.21 to 0.45) one to five years later. In otherwise healthy children with long-standing OME and hearing loss, early insertion of grommets had no effect on language development or cognition. One randomised controlled trial in children with OME more than nine months, hearing loss and disruptions to speech, language, learning or behaviour showed a very marginal effect of grommets on comprehensive language. AUTHORS' CONCLUSIONS: The benefits of grommets in children appear small. The effect of grommets on hearing diminished during the first year. Potentially adverse effects on the tympanic membrane are common after grommet insertion. Therefore an initial period of watchful waiting seems to be an appropriate management strategy for most children with OME. As no evidence is yet available for the subgroups of children with speech or language delays, behavioural and learning problems or children with defined clinical syndromes (generally excluded from the primary studies included in this review), the clinician will need to make decisions regarding treatment for such children based on other evidence and indications of disability related to hearing impairment. This review does not resolve the discrepancy between parental and clinical observation of a beneficial treatment effect and the results in the reviewed RCT showing only a short-term effect on hearing and virtually no effect on development. Is the perceived, often dramatic, effect of grommets only a short-term one? Are some children more sensitive to OME-related hearing loss than others? If so, how do we identify them?Further research should focus upon indications. Studies should use sufficiently large sample sizes to show significant interactions. There is a need to determine the most suitable variables and appropriate "softer" outcomes to be the subject of these interaction tests. Interesting options include measures of speech-in-noise and binaural hearing. The generally modest results in the trials which are included in this review should make it easier to justify randomisation of more severely affected and higher-risk children in appropriately constructed trials. Randomised controlled trials are necessary in these children before more detailed conclusions about the effectiveness of grommets can be drawn.

Child↗

Using enquiry in learning: from vision to reality in higher education.

This paper reports on the contribution of six nurse educators to embed enquiry-led learning in a pre-registration nursing programme. Their focus was to evaluate student and facilitator perspectives of a hybrid model of problem-based learning, a form of enquiry-based learning and to focus on facilitators' perceptions of its longer-term utility with large student groups. Problem-based learning is an established learning strategy in healthcare internationally; however, insufficient evidence of its effectiveness with large groups of pre-registration students exists. Fourth Generation Evaluation was used, applying the Nominal Group Technique and Focus Group interviews, for data collection. In total, four groups representing different branches of pre-registration students (n = 121) and 15 facilitators participated. Students identified seven strengths and six areas for development related to problem-based learning. Equally, analysis of facilitators' discussions revealed several themes related to strengths and challenges. The consensus was that using enquiry aided the development of independent learning and encouraged deeper exploration of nursing and allied subject material. However, problems and frustrations were identified in relation to large numbers of groups, group dynamics, room and library resources and personal development. The implications of these findings for longer-term utility with large student groups are discussed.

Attitude of Health Personnel↗

The papers of Cicely Williams (1893-1992) in the Contemporary Medical Archives Centre at the Wellcome Institute.

The papers of Cicely Williams were given to the Contemporary Medical Archives Centre in 1993, and subsequently catalogued. They cover most aspects of her work in the field of maternal and child health, as practitioner, teacher and consultant, 1929-1989, especially in the developing world. The collection includes correspondence, reports, lectures, publications, photographs and sound recordings, and is of relevance to a wide range of issues related to maternal and child health and the development of appropriate local health care systems. In particular, it is of interest in relation to Williams' pioneering work on the identification of the childhood malnutrition disease kwashiorkor. The Cicely Williams papers complement many other collections held by the Contemporary Medical Archives Centre. This article focuses on two pre-war reports of her work in the Gold Coast and Singapore, which show the early development of ideas which are echoed throughout the rest of her papers.

Adolescent↗

DNA fiber mapping techniques for the assembly of high-resolution physical maps.

High-resolution physical maps are indispensable for directed sequencing projects or the finishing stages of shotgun sequencing projects. These maps are also critical for the positional cloning of disease genes and genetic elements that regulate gene expression. Typically, physical maps are based on ordered sets of large insert DNA clones from cosmid, P1/PAC/BAC, or yeast artificial chromosome (YAC) libraries. Recent technical developments provide detailed information about overlaps or gaps between clones and precisely locate the position of sequence tagged sites or expressed sequences, and thus support efforts to determine the complete sequence of the human genome and model organisms. Assembly of physical maps is greatly facilitated by hybridization of non-isotopically labeled DNA probes onto DNA molecules that were released from interphase cell nuclei or recombinant DNA clones, stretched to some extent and then immobilized on a solid support. The bound DNA, collectively called "DNA fibers," may consist of single DNA molecules in some experiments or bundles of chromatin fibers in others. Once released from the interphase nuclei, the DNA fibers become more accessible to probes and detection reagents. Hybridization efficiency is therefore increased, allowing the detection of DNA targets as small as a few hundred base pairs. This review summarizes different approaches to DNA fiber mapping and discusses the detection sensitivity and mapping accuracy as well as recent achievements in mapping expressed sequence tags and DNA replication sites.

Animals↗

Speech and language therapy for dysarthria due to non-progressive brain damage.

BACKGROUND: Dysarthria is a common sequel of non-progressive brain damage (typically stroke and traumatic brain damage). Impairment-based therapy and a wide variety of compensatory management strategies are undertaken by speech and language therapists with this patient population. OBJECTIVES: To determine the efficacy of speech and language therapy interventions for adults with dysarthria following non-progressive brain damage. SEARCH STRATEGY: This review has drawn on the search strategies developed for the following Cochrane Groups as a whole: Stroke, Injuries, and Infectious Diseases. Relevant trials were identified in the Specialised Registers of Controlled Trials (see Review Group Details for more information). We also searched the trials register of the Cochrane Rehabilitation and Related Therapies Field. The Cochrane Controlled Trials Register, MEDLINE, EMBASE, CINAHL, PsycLIT, and Linguistics and Language Behavior Abstracts were electronically searched. Hand-searching of The International Journal of Language and Communication Disorders and of reference lists from relevant articles and conference proceedings was also undertaken. Colleagues were approached to identify other possible published and unpublished studies. Date of most recent searches: May 2000. SELECTION CRITERIA: Unconfounded randomised controlled trials. DATA COLLECTION AND ANALYSIS: One reviewer assessed trial quality. Two co-reviewers were available to examine any potential trials for possible inclusion in the review. MAIN RESULTS: No trials of the required standard were identified. REVIEWER'S CONCLUSIONS: There is no evidence of the quality required by this review to support or refute the effectiveness of Speech and Language Therapy interventions for dysarthria following non-progressive brain damage. There is an urgent need for good quality research in this area.

Adult↗

Detection of distinct species in purified human respiratory mucin using monoclonal antibodies.

The purpose of this investigation was to demonstrate the presence of different species (subpopulations) in the purified human tracheobronchial mucin (HTM-1). Mucin was highly purified from sputum specimens collected from a cystic fibrosis (CF) patient using a protocol involving sequential chromatography on Bio-Gel A-5m and hydroxylapatite columns. SDS-composite gel electrophoresis followed by periodic acid-Schiff's reagent staining was unable to detect mucin species. However, using enzyme-linked immunoelectrotransfer blot (EITB) method and polyclonal antibodies raised against HTM-1, at least four different migrating mucin species were detected. Further immunological characterization of these mucin species was carried out using a library of 16 monoclonal antibodies (MAbs) developed against the purified mucin. Nine MAbs belonged to the IgM class, two MAbs were IgG1, one IgG2a and remaining four were of the IgG3 subclass. Periodate oxidation of the mucin antigen was used to establish the nature of the mucin epitopes recognized by the MAbs. 11 MAbs recognized carbohydrate epitopes in the mucin molecule that were sensitive to periodate, while five MAbs reacted with periodate resistant carbohydrate epitopes or the protein portion of the mucin molecule. Enzyme-linked immunoelectrotransfer blot analysis of the MAbs against HTM-1 showed the presence of at least three distinct mucin species. Chromatography of the mucin on immunoaffinity columns (MAbs H(13.3), M(33.3) and CCK 061 conjugated to CNBr-activated Sepharose 4B), followed by ELISA and EITB analyses, established the mucin species recognized by the antibodies. These experiments further indicated that both unique and shared epitopes were present in the mucin species. These monoclonal antibodies may provide a promising approach to differentiate the secretory products of the tracheobronchial tree.

Antibodies, Monoclonal↗

Large-scale expression screening by automated whole-mount in situ hybridization.

Gene expression profiling is an important component of functional genomics. We present a time and cost efficient high-throughput whole-mount in situ technique to perform a large-scale gene expression analysis in medaka fish (Oryzias latipes) embryos. Medaka is a model system ideally suited for the study of molecular genetics of vertebrate development. Random cDNA clones from an arrayed stage 20 medaka plasmid library were analyzed by whole-mount in situ hybridization on embryos of three representative stages of medaka development. cDNA inserts were colony PCR amplified in a 384-format. The PCR products were used to generate over 2000 antisense RNA digoxigenin probes in a high-throughput process. Whole-mount in situ hybridization was carried out in a robot and a broad range of expression patterns was observed. Partial cDNA sequences and expression patterns were documented with BLAST results, cluster analysis, images and descriptions, respectively; collectively this information was entered into a web-based database, "MEPD" (http://www.embl-heidelberg.de/mepd/), that is publicly accessible.

Animals↗

A Web-based classification system of DNA-binding protein families.

Rational classification of proteins encoded in sequenced genomes is critical for making the genome sequences maximally useful for functional and evolutionary studies. The family of DNA-binding proteins is one of the most populated and studied amongst the various genomes of bacteria, archaea and eukaryotes and the Web-based system presented here is an approach to their classification. The DnaProt resource is an annotated and searchable collection of protein sequences for the families of DNA-binding proteins. The database contains 3238 full-length sequences (retrieved from the SWISS-PROT database, release 38) that include, at least, a DNA-binding domain. Sequence entries are organized into families defined by PROSITE patterns, PRINTS motifs and de novo excised signatures. Combining global similarities and functional motifs into a single classification scheme, DNA-binding proteins are classified into 33 unique classes, which helps to reveal comprehensive family relationships. To maximize family information retrieval, DnaProt contains a collection of multiple alignments for each DNA-binding family while the recognized motifs can be used as diagnostically functional fingerprints. All available structural class representatives have been referenced. The resource was developed as a Web-based management system for online free access of customized data sets. Entries are fully hyperlinked to facilitate easy retrieval of the original records from the source databases while functional and phylogenetic annotation will be applied to newly sequenced genomes. The database is freely available for online search of a library containing specific patterns of the identified DNA-binding protein classes and retrieval of individual entries from our WWW server (http://kronos.biol.uoa.gr/~mariak/dbDNA.html).

Amino Acid Motifs↗

Identification of differentially expressed genes between fetal and adult mouse kidney: candidate gene in kidney development.

BACKGROUND: The kidney development involves a wide variety of developmental processes requiring a lot of genes expressed in a sequential manner. The aim of the present study is to identify new genes involved in these processes. METHODS: To obtain a view of the mouse embryonic kidney transcriptome we used the SADE method, which allows large-scale quantitative gene expression measurements. RESULTS: 7,689 tags were sequenced from our library. Among the 4,507 unique transcripts yielded, 64% correspond to known genes, 22% ESTs, 12% unidentified genes. 472 genes were differentially expressed as compared to published adult kidney library. Among these, we identified several candidate genes and focused on a particular one: thymosin beta4 (Tbeta4), an actin-sequestering protein more highly expressed in fetal kidney. First we studied the in vivo expression patterns of Tbeta4 transcript during kidney development. Tbeta4 increases throughout the kidney development and remains high during active nephrogenesis. Moreover, the spatial distribution of Tbeta4 mRNA was analysed and reveals that during active nephrogenesis (i.e., 18 dpc) Tbeta4 is localised in differentiating glomeruli. In adult kidney, Tbeta4 remains expressed in podocytes and collecting ducts. CONCLUSION: Our results provide the first demonstration of Tbeta4 production in vivo by embryonic kidney and further show that Tbeta4 is implicated in kidney organogenesis.

Aging↗

LitMiner: integration of library services within a bio-informatics application.

BACKGROUND: This paper examines how the adoption of a subject-specific library service has changed the way in which its users interact with a digital library. The LitMiner text-analysis application was developed to enable biologists to explore gene relationships in the published literature. The application features a suite of interfaces that enable users to search PubMed as well as local databases, to view document abstracts, to filter terms, to select gene name aliases, and to visualize the co-occurrences of genes in the literature. At each of these stages, LitMiner offers the functionality of a digital library. Documents that are accessible online are identified by an icon. Users can also order documents from their institution's library collection from within the application. In so doing, LitMiner aims to integrate digital library services into the research process of its users. METHODS: Case study RESULTS: This integration of digital library services into the research process of biologists results in increased access to the published literature. CONCLUSION: In order to make better use of their collections, digital libraries should customize their services to suit the research needs of their patrons.

Journal Article↗

On food and nutrition policy activities in the USA, Australia, and Norway.

Formulation and implementation of a national food and nutrition policy is important for ensuring good health and quality of life. This study examined the formulation and implementation of food and nutrition policies in the USA, Australia, and Norway. Library searches, MEDLINE and POPLINE searches, and personal communications were used for collecting information and data on nutrition activities and policy formulation and implementation in each country. These countries were selected because policy activities have been ongoing since the 1930s with a clear improvement in the nutritional status of the people. Multisectoral participation, conflicts of interest, strategies to alter diet, and attempts to deal with new problems have been highlighted and compared. Findings of the study may be useful to policy-makers in less-developed countries during future policy-making processes.

Australia↗

Beta-lactam versus beta-lactam-aminoglycoside combination therapy in cancer patients with neutropaenia.

BACKGROUND: Chemotherapy treated cancer patients are prone to neutropaenia and life-threatening infections. Early, empirical antibiotic treatment is therefore administered routinely to febrile neutropaenic patients. Currently, either beta-lactam-aminoglycoside combination treatment or beta-lactam monotherapy are recommended. OBJECTIVES: We compared beta-lactam monotherapy versus beta-lactam-aminoglycoside combination therapy for cancer patients with fever and neutroepaenia. SEARCH STRATEGY: Cochrane Library (Issue 4,2001), the Cochrane Cancer Network Register of trials (July 2000), EMBASE (January 1980-2000), MEDLINE (1966-8/2001), and ICAAC conference proceedings (1995 onwards). We scanned references of all included studies, pertinent reviews, and contacted the first author of each included trial and the pharmaceutical companies. SELECTION CRITERIA: Randomised controlled trials comparing any beta-lactam antibiotic monotherapy to any combination of a beta-lactam and an aminoglycoside antibiotic, for the initial, empirical treatment of febrile neutropaenic cancer patients. DATA COLLECTION AND ANALYSIS: Data concerning mortality, treatment failure (including treatment modifications), superinfections, adverse effects and study quality measures were extracted independently by two reviewers. Relative risks with their 95% confidence intervals (CI) were estimated. Outcomes were extracted by intention-to-treat analysis whenever possible. MAIN RESULTS: Forty-six trials and 7642 patients were included. All cause mortality was the primary outcome assessed. For all mortality comparisons, no significant difference between monotherapy and combination therapy was seen, relative risk 0.85 (95% CI 0.72-1.02) for all studies combined. Treatment failure was the outcome reported in all included trials. No significant difference between study groups was shown for studies comparing the same beta-lactam, relative risk 1.12 (95% CI 0.96-1.29). A significant advantage to monotherapy was observed for studies comparing different beta-lactams, relative risk 0.86 (95% CI 0.80-0.93). Bacterial and fungal superinfections developed with similar frequencies in the monotherapy and combination treatment groups. Adverse events were significantly more common in the combination treatment group, relative risk 0.83, (95% CI 0.72-0.97). These included events associated with significant morbidity, primarily renal toxicity. Results were consistent for subgroup and sensitivity analyses. REVIEWER'S CONCLUSIONS: We have shown an advantage to broad-spectrum beta-lactam monotherapy over beta-lactam-aminoglycoside combination therapy for febrile neutropaenia. This advantage comprises of 1) a similar, if not better, survival, 2) a significantly lower treatment failure rate, 3) comparable probability for secondary infections and, 4) most importantly, a lower rate of adverse events associated with significant morbidity. Monotherapy can be regarded, therefore, as the standard of care for febrile neutropaenic patients.

Aminoglycosides↗

Estradiol-17beta stimulates gonadotropin II expression and release in the protandrous male black porgy Acanthopagrus schlegeli Bleeker: a possible role in sex change.

The objective of the present study was to investigate the in vivo effects of sex steroids (estradiol-17beta, E(2); testosterone, T) and the nonaromatizable androgen 5alpha-dihydrotestosterone (DHT) on the levels of gonadotropin II (GTH II) in plasma and pituitary and on aromatase activity in 2-year-old male black porgy, Acanthopagrus schlegeli, during the prereproductive season. Black porgy GTH II and GTH II beta subunits were purified and anti-GTH II beta serum was induced. A specific radioimmunoassay for black porgy GTH II was developed. cDNA GTH II beta was also cloned from a black porgy pituitary cDNA library for use as a probe for Northern analysis. Male fish were divided into eight groups (n = 64): control; E(2) (3 doses, 2.4 ng, 72 ng, and 2.2 microg/g body weight); T (2 doses, 72 ng and 2.2 microg/g body weight); and DHT (2 doses, 72 ng and 2.2 microg/g body weight). Fish were injected with the respective vehicle or different doses of material on days 0, 8, and 16. Plasma was collected at 4-day intervals from days 4 to 20. Plasma GTH II concentrations were significantly increased (up to 45-fold) in the E(2) group from days 4 to 20 in a dose-dependent manner. In a further experiment during the late reproductive season, plasma GTH II levels increased at 4 h and on days 1 and 2 following a single injection of 1.0 microg E(2)/g body weight (on day 0). Androgens (T or DHT) had little or no effect on plasma GTH II. Pituitary GTH II contents on day 20 were significantly lower in the 72-ng E(2) and 2.2-microg E(2) groups but not in the 2.4-ng E(2) group compared with the control group. Pituitary GTH II beta mRNA levels were significantly stimulated in the 72-ng and 2.2-microg E(2) groups on day 20. Gonadal aromatase activity was not significantly changed in any of the treated or control groups. It is concluded that GTH II secretion in black porgy is regulated by an estrogen-specific effect. Increased plasma GTH II levels or other factors in addition to E(2) might be involved in the regulation of gonadal aromatase activity and sex change in protandrous black porgy.

Amino Acid Sequence↗