Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Serial Publications”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 361 records · Page 20Linked to original sources
PubMed1995

3D reconstruction and quantitation of pathological tissues.

3DR techniques are under continuous development, as is the technology which supports them. Systems developed for engineering and other applications are coming within the price range of many users. Recently publications have started to appear using standard high-quality graphics workstations. As these are coming down in price, more applications will be possible. The advent of new computer technology, notably possible. The advent of new computer technology, notably highly parallel systems and chips such as the Intel i860, offer the prospect of very fast reconstructions and the software to make 3DR a routine technique. Most significant however is the continuing increase in type and numbers of scanning systems, both macroscopic and microscopic. Prior to these systems becoming available, the critical limiting factor inhibiting the wide application of 3DR was generating adequately registered, undistorted, complete sets of serial section data for the reconstruction process. The fact that scanning optical microscopes can produce such datasets easily means that the everyday use of 3DR for studies of pathology is now feasible.

Humans↗
PubMed1997

Magnetic resonance imaging in juvenile rheumatoid arthritis.

OBJECTIVES: This study was undertaken to examine the role of magnetic resonance imaging (MRI) in the management of patients with juvenile rheumatoid arthritis (JRA). METHODS: A Medline search was performed to identify all publications pertaining to MRI in JRA. Further searches and identification of articles from bibliographies identified articles pertaining to plain radiograph imaging in JRA and MRI in adult rheumatoid arthritis. RESULTS: Studies in both children and adults have shown superiority of MRI to plain radiography in detecting synovial hypertrophy and articular cartilage abnormalities. Several studies in adults have shown a good correlation of MR images with gross anatomic as well as histological findings at arthroscopy. Biochemical changes that occur before structural changes within the joint may even be detectable with magnetic resonance spectroscopy. CONCLUSIONS: MRI holds promise for the assessment of disease progression in JRA and may be useful in serial evaluation, as in clinical trials.

Adolescent↗
PubMed1995

Infraputaminal 'lacunes'. Clinical and pathological correlations.

BACKGROUND AND PURPOSE: Single, oval lesions greater than 5 mm in diameter lying inferior to the lateral putamen (infraputaminal lacunes [IPLs]) seen on CT or MR images are commonly reported as lacunar infarcts. To determine the clinical relevance and underlying pathology of IPLs, we evaluated the imaging appearances, clinical features, vascular risk factors, and histopathology in patients with IPLs. METHODS: Consecutive MR scans were reviewed for the presence of IPLs. Serial patients seen in routine clinical practice with IPLs were also included. Vascular risk factors were obtained from a prescan questionnaire. Histology and microangiography were performed on postmortem material. A MEDLINE search for putaminal infarcts was performed to look for imaging lesions typical of IPLs. RESULTS: Three of 100 serial MR scans had IPLs (3%). Nine other patients with in vivo (7) or postmortem (2) MR scans had IPLs. No neurological symptoms could be related to the IPLs. There were no differences in age, hypertension, diabetes, or presence of cortical enlarged perivascular spaces (EPVSs) between patients with and without IPLs. Unlike infarcts, IPLs were isointense with the cerebrospinal fluid on proton density MR sequences. Histological correlation of three MR scans showed IPLs to be a single large EPVS, situated lateral to the anterior commissure. IPLs were located at a point where multiple lenticulostriates turn sharply dorsally. An IPL was the probable cause of the apparent infarct in six publications from peer-reviewed literature that linked different clinical signs to putaminal infarct. CONCLUSIONS: IPLs are EPVSs that can be differentiated from infarcts on proton density MR images.

Adult↗
PubMed2026

Establishment of a STAT6 Reporter Assay for Screening Environmental Toxicants Affecting Allergic Airway Inflammation.

Air pollution-associated allergic airway inflammation is an increasing public health concern. Interleukin‑4 (IL‑4) and interleukin‑13 (IL‑13), which activate the Signal Transducer and Activator of Transcription 6 (STAT6) pathway, a central mediator of allergic airway inflammation, may modulate the respiratory toxicities of pollutants. The present study describes the generation and validation of a stable STAT6 luciferase reporter assay in human airway epithelial cells for evaluating environmental toxicants that modulate STAT6 signaling. Human bronchial epithelial 16HBE14o- cells were transduced with a STAT6-responsive luciferase reporter using a lentiviral vector, followed by optimization of puromycin selection and multiplicity of infection, and monoclonal isolation by limiting dilution. A stable clone with strong and reproducible induction across serial passages was selected. Reporter responsiveness was validated by IL-4/IL-13 stimulation, and STAT6 dependence was confirmed using selective STAT6, STAT5, and STAT3 inhibitors. Assay performance was quantified by Z'-factor analysis, which indicated reproducible signal separation. Furthermore, the assay was applied to individual air-pollution constituents, and benzo[b]fluoranthene and particulate matter significantly increased STAT6 reporter activity. This method provides a scalable approach for measuring STAT6 activity in airway epithelial cells and for prioritizing environmental toxicants that modulate allergic airway signaling.

STAT6 Transcription Factor↗
PubMed1962

Human trichinosis: studies on eleven cases affecting two families in Nova Scotia.

A two-family outbreak of 11 cases of trichinosis with one fatality has been described. Efforts were made to obtain an early assessment of the severity of parasitization on the basis of initial clinical appearance, serial electrocardiograms, changes in eosinophil count, serum protein analyses and SGOT levels. The diagnoses were confirmed by muscle biopsy and by Suessenguth-Kline flocculation tests on serum. Factors portending a severe illness included: (a) rapid decline in total eosinophil count, (b) very low levels of serum albumin, (c) elevation of alpha(1)- and alpha(2)-fractions of serum proteins. A review of current serological methods available for the diagnosis of trichinosis has been presented and emphasis has been placed on the importance of interpreting laboratory tests in conjunction with clinical signs and symptoms. The severity and duration of illness in these cases have shown the importance of enforcing present public health regulations designed to prevent this illness being acquired by humans through consumption of infected pork.

Adrenocorticotropic Hormone↗
PubMed2001

Serial human passage of simian immunodeficiency virus by unsterile injections and the emergence of epidemic human immunodeficiency virus in Africa.

There is compelling evidence that both human immunodeficiency virus (HIV) types emerged from two dissimilar simian immunodeficiency viruses (SIVs) in separate geographical regions of Africa. Each of the two HIVs has its own simian progenitor and specific genetic precursor, and all of the primates that carry these SIVs have been in close contact with humans for thousands of years without the emergence of epidemic HIV. To date no plausible mechanism has been identified to account for the sudden emergence in the mid-20th century of these epidemic HIVs. In this study we examine the conditions needed for SIV to complete the genetic transition from individual human SIV infections to epidemic HIV in humans. The genetic distance from SIV to HIV and the mutational activity needed to achieve this degree of adaptation to human hosts is placed within a mathematical model to estimate the probabilities of SIV completing this transition within a single SIV-infected human host. We found that the emergence of even one epidemic HIV strain, following a single human exposure to SIV, was very unlikely. And the probability of four or more such transitions (i.e. HIV-1 groups M, O and HIV-2 subtypes A and B) occurring in a brief period is vanishingly small. We conclude that SIV cannot become a zoonosis, but requires adaptive mutations to become HIV. Some modern event must have aided in the transition of SIV to HIV. Our research indicates that serial passage of partially adapted SIV between humans could produce the series of cumulative mutations sufficient for the emergence of epidemic HIV strains. We examined the rapid growth of unsterile injections in Africa beginning in the 1950s as a biologically plausible event capable of greatly increasing serial human passage of SIV and generating HIV by a series of multiple genetic transitions. We conclude that increased unsterile injecting in Africa during the period 1950-1970 provided the agent for SIV human infections to emerge as epidemic HIV in the modern era.

Africa↗
PubMed2001

[Nosocomial infection: medical responsibility regarding the law].

The nosocomial infection, infection transmitted to a patient at the time of medical care, constitutes a complex nosological framework. The knowledge of the risk factors is essential to their good management. It underlies all the lawful texts concerning the fight against the nosocomial infections. These texts propose to us definitions established in a context of public hygiene and health. The complexity and the cost of the management of all these risks can only be compared with jurisprudential simplification, which results from this in responsibility matters. In a pro indemnity concern, the position of the "Cour de Cassation" is closely akin to the rigor of the "Conseil d'état", which imposes the uncompromising presumption of fault against supposed guilty, persons or entities. It is necessary to redefine the risks towards praetorian right. It is the role of the legal expert, auxiliary of the judge, to provide in equity an informed opinion on the facts. The factual criteria must allow a modulation of responsibility concerning the fault, the serial risk or the medical risk.

Cross Infection↗
PubMed2005

Community analysis of a full-scale anaerobic bioreactor treating paper mill wastewater.

To get insight into the microbial community of an Upflow Anaerobic Sludge Blanket reactor treating paper mill wastewater, conventional microbiological methods were combined with 16S rRNA gene analyses. Particular attention was paid to microorganisms able to degrade propionate or butyrate in the presence or absence of sulphate. Serial enrichment dilutions allowed estimating the number of microorganisms per ml sludge that could use butyrate with or without sulphate (10(5)), propionate without sulphate (10(6)), or propionate and sulphate (10(8)). Quantitative RNA dot-blot hybridisation indicated that Archaea were two-times more abundant in the microbial community of anaerobic sludge than Bacteria. The microbial community composition was further characterised by 16S rRNA-gene-targeted Denaturing Gradient Gel Electrophoresis (DGGE) fingerprinting, and via cloning and sequencing of dominant amplicons from the bacterial and archaeal patterns. Most of the nearly full length (approximately 1.45 kb) bacterial 16S rRNA gene sequences showed less than 97% similarity to sequences present in public databases, in contrast to the archaeal clones (approximately. 1.3 kb) that were highly similar to known sequences. While Methanosaeta was found as the most abundant genus, also Crenarchaeote-relatives were identified. The microbial community was relatively stable over a period of 3 years (samples taken in July 1999, May 2001, March 2002 and June 2002) as indicated by the high similarity index calculated from DGGE profiles (81.9+/-2.7% for Bacteria and 75.1+/-3.1% for Archaea). 16S rRNA gene sequence analysis indicated the presence of unknown and yet uncultured microorganisms, but also showed that known sulphate-reducing bacteria and syntrophic fatty acid-oxidising microorganisms dominated the enrichments.

Anaerobiosis↗
PubMed2004

Bayesian model accounting for within-class biological variability in Serial Analysis of Gene Expression (SAGE).

BACKGROUND: An important challenge for transcript counting methods such as Serial Analysis of Gene Expression (SAGE), "Digital Northern" or Massively Parallel Signature Sequencing (MPSS), is to carry out statistical analyses that account for the within-class variability, i.e., variability due to the intrinsic biological differences among sampled individuals of the same class, and not only variability due to technical sampling error. RESULTS: We introduce a Bayesian model that accounts for the within-class variability by means of mixture distribution. We show that the previously available approaches of aggregation in pools ("pseudo-libraries") and the Beta-Binomial model, are particular cases of the mixture model. We illustrate our method with a brain tumor vs. normal comparison using SAGE data from public databases. We show examples of tags regarded as differentially expressed with high significance if the within-class variability is ignored, but clearly not so significant if one accounts for it. CONCLUSION: Using available information about biological replicates, one can transform a list of candidate transcripts showing differential expression to a more reliable one. Our method is freely available, under GPL/GNU copyleft, through a user friendly web-based on-line tool or as R language scripts at supplemental web-site.

Astrocytoma↗
PubMed2003

Provocation studies in the diagnosis of occupational asthma.

Specific and nonspecific provocation studies, although not always essential for diagnosing OA, help confirm the diagnosis and identify the offending agent. Nonspecific bronchial challenge testing is used to detect airway hyperresponsiveness and to clarify the nature of the patient's symptoms. Pharmacologic bronchoconstrictor agents (eg, methacholine, histamine) most commonly are used for the challenge, but nonisotonic aerosols, exercise and hyperventilation also can show airway hyperresponsiveness. Nonspecific challenges usually are done in the laboratory, but can be done at the workplace if emergency equipment is available. A comparison of results obtained at and away from the workplace (at least 1 week apart) may be helpful in diagnosing OA. Specific bronchial challenge testing is considered the gold standard for OA diagnosis. It can be crucial in helping physicians, employers, and employees make decisions about continued employment, compensation, career changes, and treatment. Testing can pinpoint new industrial agents that cause OA, enabling dissemination of information on its hazards to the public and within the industry. The nature of the agent determines the type of protocol that is used for testing. Agents can be in the form of dusts, powders, aerosols, vapors gases, and animal dander. Exposure can be as simple as having patients simulate their work activities, or as complicated as using special challenge chambers with controlled environments and precise delivery of agents. Performing control challenges with a component that is separate from the test agent is essential to avoid false-positive results. The timing, duration, and dosing of exposure depend on the type of reaction that has been experienced previously, the nature of the agent, and the patient's baseline airway hyperresponsiveness. Serial spirometry and observation often are done for up to 8 hours to monitor early and late reactions. SBC testing should be performed in the proper medical setting in which emergency equipment available and should be administered only by healthcare personnel who are trained and experienced in the procedures. Safety of the patient is the primary consideration.

Asthma↗
PubMed1999

Induction and pharmacological treatment of oral osteopenia in rats.

BACKGROUND: Osteoporosis is a major public health problem, responsible for a great number of fractures, associated with devastating costs to society. In addition, oral bone loss has an enormous impact on the health quality of life of patients, affecting up to 90% of elderly individuals. The aim of this work was to elaborate an animal model of mandibular and maxillary osteoporosis in which to evaluate bone loss and possible prevention by pharmacological treatment. METHODS: Six Sprague-Dawley rats were gonadectomized and treated with clodronate (male) or 17 beta-estradiol (female) for two months. Six gonadectomized and six sham-operated rats of both sexes were treated with placebo. The mandible and maxilla, fixed and methacrylate embedded, were serially sectioned, microradiographed and processed for histomorphometric analysis. RESULTS: Gonadectomy did not modify the amount of compact and trabecular bone in mandibles of rats of either sex, treated or not with clodronate or estrogens, compared to sham-operated rats. Compared to sham-operated rats, a 10-25% increase of bone porosity was found in the maxilla of ovariectomized rats, either receiving estrogens or not, while in male rats no difference among groups could be evidenced. CONCLUSIONS: The conclusion is drawn that rats, due to their peculiar masticatory habits yielding huge loads on oral bones, do not represent a suitable experimental model for studying oral bone loss related to skeletal osteoporosis. In order to worsen oral osteopenia it would be mandatory to combine gonadectomy with a mechanical unloading (i.e. after molar extraction) of mandibular or maxillary bone.

Animals↗
PubMed2006

Neurobehavioral effects among inhabitants around mobile phone base stations.

BACKGROUND: There is a general concern on the possible hazardous health effects of exposure to radiofrequency electromagnetic radiations (RFR) emitted from mobile phone base station antennas on the human nervous system. AIM: To identify the possible neurobehavioral deficits among inhabitants living nearby mobile phone base stations. METHODS: A cross-sectional study was conducted on (85) inhabitants living nearby the first mobile phone station antenna in Menoufiya governorate, Egypt, 37 are living in a building under the station antenna while 48 opposite the station. A control group (80) participants were matched with the exposed for age, sex, occupation and educational level. All participants completed a structured questionnaire containing: personal, educational and medical histories; general and neurological examinations; neurobehavioral test battery (NBTB) [involving tests for visuomotor speed, problem solving, attention and memory]; in addition to Eysenck personality questionnaire (EPQ). RESULTS: The prevalence of neuropsychiatric complaints as headache (23.5%), memory changes (28.2%), dizziness (18.8%), tremors (9.4%), depressive symptoms (21.7%), and sleep disturbance (23.5%) were significantly higher among exposed inhabitants than controls: (10%), (5%), (5%), (0%), (8.8%) and (10%), respectively (P<0.05). The NBTB indicated that the exposed inhabitants exhibited a significantly lower performance than controls in one of the tests of attention and short-term auditory memory [Paced Auditory Serial Addition Test (PASAT)]. Also, the inhabitants opposite the station exhibited a lower performance in the problem solving test (block design) than those under the station. All inhabitants exhibited a better performance in the two tests of visuomotor speed (Digit symbol and Trailmaking B) and one test of attention (Trailmaking A) than controls. The last available measures of RFR emitted from the first mobile phone base station antennas in Menoufiya governorate were less than the allowable standard level. CONCLUSIONS AND RECOMMENDATIONS: Inhabitants living nearby mobile phone base stations are at risk for developing neuropsychiatric problems and some changes in the performance of neurobehavioral functions either by facilitation or inhibition. So, revision of standard guidelines for public exposure to RER from mobile phone base station antennas and using of NBTB for regular assessment and early detection of biological effects among inhabitants around the stations are recommended.

Adult↗
PubMed1996

Effectiveness of influenza vaccine in the elderly.

OBJECTIVE: Each year, influenza and its complications account for 10,000-40,000 excess deaths in the United States. Over 80% of these deaths occur among the elderly. The Advisory Committee on Immunization Practices for the US Public Health Service and others recommend that all persons 65 years of age and older as well as other persons with high-risk conditions receive annual influenza vaccination. Despite these recommendations, 40% or more of high-risk persons fail to receive influenza vaccine. Among the barriers to successful immunization efforts are persistent uncertainties regarding the effectiveness of the vaccine in preventing morbidity and mortality associated with influenza. The purpose of this study was to assess influenza vaccine effectiveness in reducing hospitalization rates for a broad range of influenza-associated complications, in reducing deaths from all causes, and in reducing hospitalization costs among all elderly enrollees of a large health maintenance organization. METHODS: A serial cohort study with internal controls was designed. All enrollees, 65 years of age and older, were identified for each of three consecutive vaccination and subsequent influenza seasons for 1990-1991 through 1992-1993. Baseline characteristics and outcome data were collected from computerized, linked, administrative data bases. Outcomes were adjusted for the presence of baseline characteristics including age, gender, high-risk diagnoses, medication refills in high-risk therapeutic classes, and previous health care resource utilization. RESULTS: There were more than 25,000 seniors in each of the three study cohorts. Influenza vaccination rates ranged from 45 to 58%, and vaccinated subjects at baseline appeared to be 'sicker' than nonvaccinated subjects. Influenza vaccination was associated with significant reductions in all outcomes evaluated including outpatient visits (17% reduction in pneumonia and influenza visits, 6.4% reduction in all respiratory condition visits), hospitalizations (51.2% reduction in pneumonia and influenza hospitalizations, 32.5% reduction in all respiratory condition hospitalizations, 28.6% reduction in congestive heart failure hospitalizations), hospitalization costs (30.7% reduction in hospitalization costs for all respiratory conditions and congestive heart failure combined), and deaths from all causes (45% reduction in death from all causes). CONCLUSIONS: Influenza vaccination of elderly persons living in the community is associated with reduced hospitalizations from complications from influenza, with fewer deaths during the influenza season, and with direct health care cost savings. Few, if any, other preventive or therapeutic interventions for adults match or exceed these benefits.

Aged↗
PubMed1984

Mouse mutants as models in endocrine research.

Although Shire (1979) has listed some forty-eight mouse mutants of interest to the endocrinologist, this short review has concentrated upon eleven mutations which have resulted in a significant number of scientific publications over the last 4 or 5 years. The selection of references has had to be limited, but it should be possible easily to expand the list given in this review. Although the proximate cause of none of the eleven mutations has been identified with certainty, the abnormalities of function have included hormone deficiencies and receptor and post-receptor malfunctions. It is perhaps a reflexion on our society in the 1980s, that the bulk of research has concentrated on the obese mouse. However, we still do not know the initial cause of this syndrome. The major disadvantage of the mouse to the hormone assayist lies in the small blood volume and the extreme difficulty in taking serial blood samples over a short period of time. With increased sophistication of assay techniques this may prove less daunting, but is an area where a review of the literature reveals discrepancies between laboratories, and even between data generated by the same laboratory at different times. With regard to the hormone content of endocrine tissues, the way forward for peptide-secreting glands may be in the measurement of mRNA levels for particular hormones. Certainly the methods of recombinant-DNA technology will yield positive information upon the aetiology and expression of some of the syndromes considered above. Organ transplantation is an area in which mutant mice have proved useful, for example gonadal, pituitary and pancreatic tissue transplantation. The grafting of neural tissue in the hpg mouse has added a further dimension to this field of research. The great infrastructure of genetical research in mice has enabled us to breed mutant genes onto different genetic backgrounds. This area of research is one which deserves to expand. The techniques of in vitro fertilization, chimera formation and embryo transfer have been used, in part, in studies on mouse mutants, and should provide technical means for further investigating gene expression. The family of dwarf mutants are ideally suited for research into the expression of genes micro-injected into the fertilized egg (see Charlton & Cox, 1983). As new hormones are isolated and become available for study these mouse mutants may well be useful in delineating physiological functions for natural and pharmacological products.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed2003

Serial analysis of gene expression in turkey sperm storage tubules in the presence and absence of resident sperm.

Turkey sperm lose viability within 8-18 h when stored as liquid semen using current methods and extenders. In contrast, turkey hens maintain viable, fertile sperm in their sperm storage tubules (SST) for 45 or more days following a single insemination. Our long-term objectives are to identify and characterize differentially expressed genes that may underlie this prolonged sperm storage and then use this information to develop improved methods for storing liquid turkey semen. We employed serial analysis of gene expression (SAGE) to compare gene expression patterns in turkey SST recovered from hens after artificial insemination (AI) with extended semen (sperm AI) or extender alone (control AI). We constructed two separate SAGE libraries with SST RNA obtained from sperm and control AI hens. We used these libraries to generate 95,325 ten-base pair SAGE tags. These 95,325 tags represented 27,430 unique genes. The sperm and control AI libraries contained 47,663 and 47,662 tags representing 18,030 and 19,101 putative unique transcripts, respectively. Approximately 1% of these putative unique genes were differentially expressed (P<0.05) between treatments. Tentative annotations were ascribed to the SAGE tag nucleotide sequences by comparing them against publicly available SAGE tag and cDNA sequence databases. Based on its SAGE tag nucleotide sequence, we cloned a partial turkey avidin cDNA and confirmed its up-regulation in the sperm AI SST. The bioinformatics and experimental procedures employed to clone turkey avidin and confirm its differential expression represent a useful paradigm for analyzing SAGE tag data from relatively uncharacterized model systems.

Animals↗
PubMed2006

Long serial analysis of gene expression for gene discovery and transcriptome profiling in the widespread marine coccolithophore Emiliania huxleyi.

The abundant and widespread coccolithophore Emiliania huxleyi plays an important role in mediating CO2 exchange between the ocean and the atmosphere through its impact on marine photosynthesis and calcification. Here, we use long serial analysis of gene expression (SAGE) to identify E. huxleyi genes responsive to nitrogen (N) or phosphorus (P) starvation. Long SAGE is an elegant approach for examining quantitative and comprehensive gene expression patterns without a priori knowledge of gene sequences via the detection of 21-bp nucleotide sequence tags. E. huxleyi appears to have a robust transcriptional-level response to macronutrient deficiency, with 42 tags uniquely present or up-regulated twofold or greater in the N-starved library and 128 tags uniquely present or up-regulated twofold or greater in the P-starved library. The expression patterns of several tags were validated with reverse transcriptase PCR. Roughly 48% of these differentially expressed tags could be mapped to publicly available genomic or expressed sequence tag (EST) sequence data. For example, in the P-starved library a number of the tags mapped to genes with a role in P scavenging, including a putative phosphate-repressible permease and a putative polyphosphate synthetase. In short, the long SAGE analyses have (i) identified many new differentially regulated gene sequences, (ii) assigned regulation data to EST sequences with no database homology and unknown function, and (iii) highlighted previously uncharacterized aspects of E. huxleyi N and P physiology. To this end, our long SAGE libraries provide a new public resource for gene discovery and transcriptional analysis in this biogeochemically important marine organism.

Base Sequence↗
PubMed2003

High-throughput epidemiologic typing in clinical microbiology.

Mapping, and ultimately preventing, the dissemination of infectious agents is an important topic in public health. Newly developed molecular-microbiological methods have contributed significantly to recent advances in the efficient tracking of the nosocomial and environmental spread of microbial pathogens. Not only has the application of novel technologies led to improved understanding of microbial epidemiology, but the concepts of population structure and dynamics of many of the medically significant microorganisms have advanced significantly also. Currently, genetic identification of microbes is also within the reach of clinical microbiology laboratory professionals including those without specialized technology research interests. This review summarizes the possibilities for high-throughput molecular-microbiological typing in adequately equipped medical microbiology laboratories from both clinical and fundamental research perspectives. First, the development and application of methods for large-scale comparative typing of serially isolated microbial strains are discussed. The outcome of studies employing these methods allows for long-term epidemiologic surveillance of infectious diseases. Second, recent methods enable an almost nucleotide-by-nucleotide genetic comparison of smaller numbers of strains, thereby facilitating the identification of the genetic basis of, for instance, medically relevant microbiological traits. Whereas the first approach provides insights into the dynamic spread of infectious agents, the second provides insights into intragenomic dynamics and genetic functionality. The current state of technology is summarized, and future perspectives are sketched.

Bacterial Infections↗
PubMed1991

Chemical face peels.

Application of caustic chemicals to improve cosmesis and reverse actinic damage has been used for centuries. Although still not an exact science, it was not until the latter part of this century that peeling became more systematized. The indications, patient selection, armamentarium, histology, comprehension of the mechanisms of action, and safety parameters of peels have only recently become more extensively defined. Phenol, when used in the Baker's formula, provides the most dramatic results but also holds the most potential for systemic complications. Ideally suited for fair-skinned women, a phenol peel can provide substantial improvement in rhytidosis and actinic damage. Although the results of medium-depth peels approach those of Baker's peels, they are not quite as profound. Use of TCA and the medium-depth peels has filled an important gap between deep and superficial peels, however. Also ideal for light complexions, this category of peels lightens pigmentary problems and improves rhytides with minimal potential for systemic toxicity; however, local complications, including scarring and pigmentary anomalies, should not be underestimated. [table: see text] Superficial peels do not effectively eradicate the ravages of time and sun, but when done repetitively, they do improve pigmentary irregularities and may improve some minor surface changes and thus impart a fresher appearance to facial skin. Although pigmentary changes can occur, superficial peels are relatively safe, and maximal results can be achieved with serial applications. Peels have been categorized by patient indications and the corresponding depth of peeling required for improvement (Table 4). The depth is determined in turn by a host of factors (Table 5). Neither the classification scheme nor the peel process should be viewed dogmatically. Patients will often benefit from the concurrent use of different skin preparations and wounding agents. Localized gradations can be achieved not only with occlusion but also by employing different solutions as well as different concentrations of the same solution and skin preparation. Selection of the appropriate technique relies on critical analysis of the skin defect one wishes to treat balanced against the risks of treatment. The final protocol should be individualized for the needs of each patient. Despite heightened public awareness of the harmful effects of ultraviolet radiation, actinically damaged skin is no longer a problem restricted to an older-patient population. Fueled by the lay press and practitioners, there is a growing patient demand for chemical peels. Chemical peels alone or combined with ancillary aesthetic procedures can provide a dramatic improvement in facial appearance. The potential for improved cosmesis is not without inherent risk, however.(ABSTRACT TRUNCATED AT 400 WORDS)

Chemexfoliation↗