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PubMed1979

Rationale for a program in community ophthalmology.

The high incidence of eye abnormalities among blacks, coupled with the relative unavailability of ophthalmic services, has resulted in excessive rates of blindness otherwise preventable or curable. As a consequence, incidence rates for blindness are higher for the black population than the white population.Statistics show that black children requiring eyeglasses are less likely to receive eyeglasses than similar age-matched white children. In virtually every state surveyed, blacks were more frequently and severely afflicted with eye diseases and were less likely to receive treatment than whites. Yet, no programs exist in any state specifically targeted to promote eye care among blacks and reverse the ever-worsening trend. Additional data characterizing the scope of the problem shall be presented.An initial strategy for approaching the problem, namely, community ophthalmology, has been developed. Community ophthalmology represents a new discipline promoting eye health and blindness prevention through programs utilizing methodologies of public health, community medicine, and ophthalmology. Basically, the use of community ophthalmology strategies is critical to positive out-come, when given a population composed of blacks and other minorities who are chronically underserved with regard to all sectors of health.The evolution and rationale for these concepts are discussed from national, as well as international, perspectives.

Adolescent↗
PubMed1997

Evolutive study of the functional results after restorative proctocolectomy for ulcerative colitis.

AIM: Evolutive study of the functional results after restorative proctocolectomy for ulcerative colitis. PATIENTS AND METHODS: Prospective study in 24 patients with an ileoanal "J" pouch (n = 8: mucosectomy and hand-sewn anastomosis; n = 16: stapled anastomosis without mucosectomy). A clinical survey was carried out during two evolutive follow-ups of the functional pouch (medians: 14.5 and 39.0 months) as well as an anorectal manometry study during the preoperative period and in two follow-ups after the creation of the pouch (medians: 6.0 and 35.5 months). RESULTS: The mean frequency of defecation per 24 hours and per night was significantly reduced in the first follow-up (5.5 [24 h]; p < 0.003 and 1.0 [per night]; p < 0.009) compared with the postoperative period (7.9 [24 h] and 1.4 [per night]), with no significant changes in the second follow-up (5.5 [24 h] and 0.9 [per night]). At the same time, it has been significantly lower in patients with stapled anastomosis in the different evolutive follow-ups. One patient (4.2%) had major fecal incontinence in the two evolutive follow-ups and 7 (29.2%) and 6 (25%) patients had minor incontinence in the first and second follow-up respectively. The mean maximum resting anal pressure in the first follow-up was significantly lower (p = 0.002) in patients with mucosectomy than the values observed in patients with stapled anastomosis (35.4 vs 68.0 mmHg). In the second follow-up increased significantly (p = 0.046) only in patients with mucosectomy (55.1 mmHg). Recto-anal inhibitory reflex was present in 2 (10%) and 9 (45%) patients in the first and second follow-up respectively. CONCLUSIONS: The functional results improve significantly with the follow-up time, fundamentally during the first year of the functional pouch.

Adult↗
PubMed2006

Molecular size evolution of oligomers in organic aerosols collected in urban atmospheres and generated in a smog chamber.

Only a minor fraction of the total organic aerosol mass can be resolved on a molecular level. High molecular weight compounds in organic aerosols have recently gained much attention because this class of compound potentially explains a major fraction of the unexplained organic aerosol mass. These compounds have been identified with different mass spectrometric methods, and compounds with molecular masses up to 1000 Da are found in secondary organic aerosols (SOA) generated from aromatic and terpene precursors in smog chamber experiments. Here, we apply matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to SOA particles from two biogenic precursors, alpha-pinene and isoprene. Similar oligomer patterns are found in these two SOA systems, but also in SOA from trimethylbenzene, an anthropogenic SOA precursor. However, different maxima molecular sizes were measured for these three SOA systems. While oligomers in alpha-pinene and isoprene have sizes mostly below 600-700 Da, they grow up to about 1000 Da in trimethylbenzene-SOA. The final molecular size of the oligomers is reached early during the particle aging process, whereas other particle properties related to aging, such as the overall acid concentration or the oligomer concentration, increase continuously over a much longer time scale. This kinetic behavior of the oligomer molecular size growth can be explained by a chain growth kinetic regime. Similar oligomer mass patterns were measured in aqueous extracts of ambient aerosol samples (measured with the same technique). Distinct differences between summer and winter were observed. In summer a few single mass peaks were measured with much higher intensity than in winter, pointing to a possible difference in the formation processes of these compounds in winter and summer.

Aerosols↗
PubMed2004

The evolution of eutherian chromosomes.

The gross organization of the genome of Eutheria (placental mammals) into chromosomes follows a simple architecture that, with some minor changes, is almost completely conserved for more than 100 million years in various species of almost all extant mammalian orders. Recent molecular cytogenetic results--especially those from the assumed oldest clade, the Afrotheria--suggest an ancestral karyotype that would calculate the "default" frequency of gross rearrangements to less than two changes within 10 million years of mammalian evolution. The main changes are the fission, movement and subsequent fusion of large chromosome segments or of chromosome arms. Reciprocal translocations are the exception. Chromosome numbers may have increased or decreased significantly in this fusion/fission process but, in most instances, the main architecture still remains evident. There are, however, some exceptions in mammals with extremely derived karyotypes.

Animals↗
PubMed2000

The compositional evolution of vertebrate genomes.

The compositional evolution of vertebrate genomes is characterized: (i) by one predominant conservative mode, in which nucleotide changes occur, but the base composition of DNA sequences in general, and of coding sequences in particular, does not change; and (ii) by three different shifting or transitional modes, in which nucleotide changes are accompanied by changes in the base composition of sequences. Investigations on these evolutionary modes have shed new light on a central problem in molecular evolution, namely the role played by natural selection in modulating the mutational input. This review will present first the intragenomic shifts, the 'major shifts' and the 'minor shift', and then the 'whole-genome', or 'horizontal', shift. In each case, the shifts were preceded and followed by a conservative mode of evolution. This review expands on a previous one [Bernardi, Gene 241 (2000) 3-17], and summarizes the evidence that the changes of the compositional patterns of the genome and their maintenance are controlled by Darwinian natural selection.

Animals↗
PubMed2003

Diabetes in the young: a paediatric and epidemiological perspective.

The spectrum of diabetes in the young has widened; it now includes monogenic diseases, for example the various forms of permanent and transient neonatal diabetes and MODY as well as the emerging obesity-associated Type 2 diabetes in late childhood, but the main form is still Type 1 diabetes. Age-related major medical, physiological, social and emotional problems make the clinical management of diabetes in children and adolescents a difficult task for the physician and the family. Overall glycaemic control remains moderate or poor despite a treatment schedule, which interferes with several elements of "normal" childhood. There is an up to tenfold geographical variation in the incidence of childhood Type 1 diabetes within Europe with relatively stable incidence rates in some countries (mainly northern), but dynamic increases in incidence in other countries (mainly central European).A number of nongenetic (environmental) factors have been associated with the risk of Type 1 diabetes. Among these, perinatal factors, early nutrition, growth and vaccinations, atopic diseases and vitamin D are discussed in detail. The important interplay between genes, organism and environment is illustrated with new genetic data supporting the importance of environmental pressures in the evolution of this major disease.Although Type 1 diabetes usually accounts for only a minority of the total impact of diabetes in a population, it is the predominant form of the disease in younger age-groups in most developed countries. It is estimated that on an annual basis almost 100 000 children younger than 15 years of age develop Type 1 diabetes worldwide. The autoimmune destruction of the pancreatic beta cells in Type 1 diabetes leads to absolute insulin dependence and a high rate of complications typically occurring at a relatively young age. Therefore, Type 1 diabetes places a particularly heavy burden on the individual, the family and health services.

Child↗
PubMed1981

Coronary intimal necrosis occurring as an early stage of atherosclerotic involvement.

In a population sample in whom violent accident was the cause of death, the following prevalence of coronary intimal necrosis, occurring as an independent lesion and as an early step of atherosclerotic involvement, was revealed: 2% of children 6--10 years old, 6% of children and juveniles 11--15 years old, 14% of adolescents 16--20 years old, 32% of young adults 21--25 years old, 56% of young adults 26--30 years old, 72% of mature adults 31--35 years old and 84% of mature adults 36--40 years old. In each age subgroup, the percentage of subjects with coronary intimal necrosis was greater than the percentage of subjects with coronary atherosclerotic plaques. A centrifugal extension with age of intimal necrosis, along the coronary tree in the direction of blood flow, was observed. Histologically, the coronary intimal necrosis exhibited a mucoid form, a swelling form and a dissecting form. Indirect evidence was offered that some areas of coronary intimal necrosis formed an adequate nidus for lipid and fibrin accumulation and also induced the development of a peculiar type of subendothelial connective tissue. These successive changes led to the onset of atheroma-like lesions with a prevalence of lipid deposits, or of intramural thrombi or of a fibro-hyaline cap. The onset, extent and evolution of coronary intimal necrosis was accelerated by the male sex, by some minor deviations from the basal branching anatomical pattern of the coronary arteries, by the main risk factors for coronary heart disease, as well as by some terminal diseases, such as the generalized form of sarcoidosis and the renal complications of systemic lupus erythematosus.

Adolescent↗
PubMed2001

Identification by saturation mutagenesis of a single residue involved in the alpha-galactosidase AgaB regioselectivity.

The alpha-galactosidase AgaB of Bacillus stearothermophilus displays a major 1,6 and a minor 1,3 regioselectivity. The wild-type enzyme was subjected to directed evolution (random mutagenesis and in vitro recombination) using a double screening strategy based on the elimination of the 1,6 regioselectivity and the analysis by TLC of the transglycosylation products. One of the AgaB mutants (E500) exhibited a new 1,2 regioselectivity and a rather high level of transglycosylation. The corresponding gene contains 10 mutations compared to the agaB gene and we demonstrated by saturation mutagenesis that the G442R substitution strongly contributes to the emergence of this new regioselectivity. Moreover, other single point mutations at this position led to new mutants displaying other kinds of regioselectivity demonstrating the importance of this position in the subtle kinetic control of transglycosylation.

Cloning, Molecular↗
PubMed2006

Chemistry and cosmology.

The simplest elements, hydrogen and helium, offer a remarkably rich chemistry, which has controlled crucial features of the early evolution of the universe. Theoretical models of the origin of structure (stars, galaxies, clusters of galaxies, etc.) now incorporate this chemistry in some detail. In addition to the origin of structure, cosmologists are concerned with observational tests of competing world models. Primordial chemistry may give rise to some of the earliest departures from thermodynamic equilibrium in the universe. These effects may be observable as broad-band spectroscopic distortions of the cosmic background radiation, which otherwise exhibits a nearly perfect blackbody spectrum. The chemical history of the expanding universe is followed through a detailed calculation of the evolution of the abundances of H, H+, H-, H2, H2+, H3+, and other minor species. It is shown that continuous absorption by the small concentration of H- can produce a distortion in the cosmic background spectrum with a maximum at a frequency near nu/c = 9 cm-1 (wavelength 1.1 mm). The predicted effect lies only a factor of 5 below current limits. Its detection would provide an important test of our understanding of the recombination epoch of the universe.

Journal Article↗
PubMed2002

One hundred cases of endoscopic brow lift.

The senior author's experience of using the endoscopic brow lift for rejuvenation of the upper third of the face is presented. One hundred patients underwent endoscopic brow elevation. In 98 cases this was done in combination with other aesthetic procedures. Patient follow-up ranged from 4 months to 53 months (mean: 17 months). No major complications were experienced, although a patient questionnaire identified a number of troublesome but transient minor complications. Levels of patient satisfaction were found to be high. The continuing evolution of this technique is reviewed, particularly relating to methods of brow fixation.

Adult↗
PubMed2003

Water at DNA surfaces: ultrafast dynamics in minor groove recognition.

Water molecules at the surface of DNA are critical to its equilibrium structure, DNA-protein function, and DNA-ligand recognition. Here we report direct probing of the dynamics of hydration, with femtosecond resolution, at the surface of a DNA dodecamer duplex whose native structure remains unperturbed on recognition in minor groove binding with the bisbenzimide drug (Hoechst 33258). By following the temporal evolution of fluorescence, we observed two well separated hydration times, 1.4 and 19 ps, whereas in bulk water the same drug is hydrated with time constants of 0.2 and 1.2 ps. For comparison, we also studied calf thymus DNA for which the hydration exhibits similar time scales to that of dodecamer DNA. However, the time-resolved polarization anisotropy is very different for the two types of DNA and clearly elucidates the rigidity in drug binding and difference in DNA rotational motions. These results demonstrate that hydration at the surface of the groove is a dynamical process with two general types of trajectories; the slowest of them (approximately 20 ps) are those describing dynamically ordered water. Because of their ultrafast time scale, the "ordered" water molecules are the most weakly bound and are accordingly involved in the entropic (hydration/dehydration) process of recognition.

Animals↗
PubMed2005

Serum fibrosis markers as predictors of an antifibrotic effect of interferon alfa in children with chronic hepatitis B.

OBJECTIVE: Interferon alfa (IFN-alpha) may retard hepatic fibrogenesis in adults with chronic hepatitis C. We evaluated prospectively four selected serum fibrosis markers before, immediately after and 12 months after IFN treatment of children with chronic hepatitis B (CHB). METHODS: Forty-seven children (mean age 8 years, range 4-16) with CHB underwent IFN-alpha treatment (3 MU t.i.w.) for 5 months. Fibrosis and inflammation were assessed blindly before and 12 months after the end of treatment. Serum laminin-2, collagen IV, MMP-2 and MMP-9/TIMP-1 complex were determined using automated assays. RESULTS: Twelve months after treatment had been discontinued levels of laminin-2, collagen IV and MMP-2 were decreased, and serum MMP-9/TIMP-1 complex was increased. Levels did not differ between sustained responders (42.5%) and non-responders. Similarly, fibrosis did not progress in both groups, whereas histological inflammation improved only in responders. CONCLUSIONS: A 5 month IFN-alpha treatment has no marked effect on histological liver fibrosis in children with CHB, irrespective of virological response. The evolution of serum fibrosis markers suggests they may be more sensitive to detect minor antifibrotic effects than semiquantitative follow-up histology.

Adolescent↗