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PubMed1997

Five new or recently discovered (GBV-A) virus species are indigenous to New World monkeys and may constitute a separate genus of the Flaviviridae.

In previous studies, human hepatitis viruses have been experimentally transmitted to New World monkeys of the genus Saguinus (tamarins). Recently, two Flaviviridae-like agents (GBV-A and GBV-B) were identified in tamarins that developed hepatitis following inoculation with serum of the 11th tamarin passage of a potentially new human hepatitis agent. However, it was not shown that these viruses originated from the initial inoculum. We here report the discovery of indigenous species-specific viruses related to GBV-A in several species of New World monkeys and suggest that GBV-A virus was fortuitously acquired during passage in tamarins. Sera or plasma from 98 wild-caught New World monkeys representing 10 different species was tested by RT-PCR with conserved degenerate primers to the 5' noncoding region of the genome. Viral sequences were identified in 33 animals and sequence analysis was performed on the amplicons. In addition, the genomic region corresponding to the putative NS3 RNA helicase of GBV-A was amplified from most positive animals and sequenced. We detected GBV-A-like viruses in 13 (35%) of 37 S. mystax, 7 (78%) of 9 S. nigricollis, 3 (25%) of 12 S. labiatus, 2 (50%) of 4 S. oedipus, 2 (100%) of 2 Callithrix jacchus, and 6 (50%) of 12 Aotus trivirgatus monkeys. Each positive animal was infected with a unique strain of the GBV-A-like viruses. Analysis of the 5' NC and NS3 helicase sequences revealed that these viruses could be classified into 5 major genetic groups with genetic distances equivalent to or greater than those found among major genetic groups of hepatitis C virus. Species-specific GBV-A-like viruses were found in S. mystax, S. nigricollis, S. oedipus, C. jacchus, and A. trivirgatus species. The viruses specific for S. nigricollis were closely related to GBV-A, suggesting that GBV-A was acquired by passage through this species during the initial transmission studies. The natural history of the GBV-A-like viruses was studied in serial serum samples from 9 S. mystax and 2 A. trivirgatus monkeys. Each animal was chronically infected and the viral strain did not vary during 9-27 months of follow-up. Finally, we demonstrated that four S. mystax were positive upon arrival to the United States from the country of origin. No apparent disease was associated with chronic infection of the GBV-A-like viruses. In conclusion, many New World monkeys are persistently infected with indigenous species-specific viruses that may represent a new genus within the virus family Flaviviridae.

Animals↗
PubMed1995

Parcellation of the frontal cortex of the New World monkey Callithrix jacchus by eight neurotransmitter-binding sites.

The most extensive development during primate brain evolution involves the cortex of the frontal lobe, especially its prefrontal region. The distribution of neurotransmitter receptors is unknown in this part of the cortex of New World monkeys. The respective distributions of eight different receptors for the transmitters L-glutamate (L-glu and NMDA), gamma-amino-butyric acid (GABAA), noradrenaline (alpha 1), acetylcholine (M1 and M2) and serotonin (5-HT1 and 5-HT2) were therefore studied in cortical areas of the frontal lobe of the lissencephalic New World monkey, Callithrix jacchus. The results are compared to earlier data on Old World monkeys in order to obtain insight into evolutionary trends at the level of chemical neuroanatomy. Our results indicate that the density and laminar pattern of some receptors change precisely at the cytoarchitectonic boundaries between different cortical areas, while some other receptors do not exhibit measurable changes. For example, the premotor area 6 can be distinguished from prefrontal areas by its high concentration of adrenergic alpha 1 receptors as labelled with [3H] prazosin, with only the cingulate area 24 showing higher values. In other cases, the receptor distribution changes within a cytoarchitectonically homogeneous area. Thus, area 8 can be subdivided into dorsal and ventral regions on the basis of the distribution of GABAA, muscarinic and serotonin receptors. Comparison of these results in a New World monkey with receptor distributions in other primate species reveals much larger interspecies differences in the areas of the frontal lobe than e.g. in the primary visual cortex.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1988

Complete pattern of ocular dominance stripes in V1 of a New World monkey, Cebus apella.

The presence of ocular dominance (OD) stripes in layer IVc of striate cortex (V1) is characteristic of all Old World simians so far studied. In contrast, some species of New World monkeys do not have ocular dominance stripes, and in those that do, the pattern of stripes may be different from that shown in Old World monkeys. This difference has led to the suggestion that OD stripes evolved independently in both groups. We have mapped the entire system of OD stripes in the New World monkey Cebus, by means of cytochrome oxidase histochemistry after monocular enucleation. A striking similarity was found between the patterns in Cebus and Macaca, which is suggestive of common ancestry, rather than parallel evolution.

Animals↗
PubMed1992

Hip fractures in the elderly: a world-wide projection.

Hip fractures are recognized to be a major public health problem in many Western nations, most notably those in North America, Europe and Oceania. Incidence rates for hip fracture in other parts of the world are generally lower than those reported for these predominantly Caucasian populations, and this has led to the belief that osteoporosis represents less of a problem to the nations of Asia, South American and Africa. Demographic changes in the next 60 years, however, will lead to huge increases in the elderly populations of those countries. We have applied available incidence rates for hip fracture from various parts of the world to projected populations in 1990, 2025 and 2050 in order to estimate the numbers of hip fractures which might occur in each of the major continental regions. The projections indicate that the number of hip fractures occurring in the world each year will rise from 1.66 million in 1990 to 6.26 million by 2050. While Europe and North America account for about half of all hip fractures among elderly people today, this proportion will fall to around one quarter in 2050, by which time steep increases will be observed throughout Asia and Latin America. The results suggest that osteoporosis will truly become a global problem over the next half century, and that preventive strategies will be required in parts of the world where they are not currently felt to be necessary.

Adult↗
PubMed2003

Neurofilament protein expression in the geniculostriate pathway of a New World monkey ( Callithrix jacchus).

We examined the expression profile of non-phosphorylated neurofilament protein in the dorsal lateral geniculate nucleus (LGN) and striate cortex (V1) of a New World simian, the marmoset monkey, using the monoclonal antibody SMI-32. The overall distribution of neurofilament protein in the marmoset resembled that previously described in Old World monkeys. While immunostained neurones were observed throughout the LGN, there were clear laminar differences in terms of both cellular and neuropil labelling. Neurones in the magnocellular layer cells stained more densely than those in the parvocellular layers. The marmoset's well-defined koniocellular layers showed an overall light stain of both neurones and neuropil. In V1, densely stained pyramidal cells and heavy neuropil label were observed in the two sublayers that send projections to the middle temporal area (MT): a supragranular band located in layer 3C (Brodmann's layer 4B) and an infragranular band located near the top of layer 6. More lightly stained, small pyramidal cells were also found in layer 3Balpha. Accordingly, in both New World and Old World monkeys the expression of neurofilament protein is correlated with specific functional subdivisions of the geniculocortical pathway. In particular, projection neurones associated with fast-conducting pathways to the extrastriate 'dorsal stream' appear to contain higher levels of this protein.

Animals↗
PubMed2000

"Third tier" ventral extrastriate cortex in the New World monkey, Cebus apella.

The ventral extrastriate cortex adjacent to the second visual area was studied in the New World monkey Cebus apella, using anaesthetised preparations. The visuotopic organisation and myeloarchitecture of this region demonstrate the existence of a distinct strip of cortex, 3-4 mm wide, with an ordered representation of the contralateral upper visual quadrant, up to 60 degrees eccentricity. This upper-quadrant representation is probably homologous to the ventral subdivision of the third visual complex (V3v) of Old World monkeys, also known as the ventral posterior area. The representation of the horizontal meridian in V3v forms its posterior and medial border with V2, while the upper vertical meridian is represented anterior and laterally, forming a congruent border with the fourth visual area (V4). Central visual fields are represented in posterior and lateral portions of V3v, in the inferior occipital sulcus, while the periphery of the visual field is represented anteriorly, on the tentorial surface. Cortex anterior to V3v, at the ventral occipitotemporal transition, had neurones that had poor visual responses. No representation of the lower quadrant was found adjacent to V3v in ventral cortex. However, we observed cells with perifoveal receptive fields centred in the lower quadrant immediately dorsal to V3v, around the junction of the inferior occipital and lunate sulci. These observations argue against the idea that V3v is an area restricted to the ventral cortex in New World monkeys and support the conclusions of previous anatomical studies in Cebus that showed a continuity of myeloarchitecture and connectional patterns between ventral and lateral extrastriate cortices. Together, these data suggest that V3v may be part of a larger area that extends into dorsolateral extrastriate cortex, overlapping to some extent with the caudal subdivision of the dorsolateral area described in other New World monkeys.

Animals↗
PubMed2000

Convergent evolution of major histocompatibility complex molecules in humans and New World monkeys.

In both Old World and New World monkeys Mhc-DRB sequences have been found which resemble human DRB1*03 and DRB3 genes in their second exon. The resemblance is shared sequence motifs and clustering of the genes or the encoded proteins in phylogenetic trees. This similarity could be due to common ancestry, convergence at the molecular level, or chance. To test which of these three explanations applies, we sequenced segments of New World monkey and macaque genes which encompass the entire second exon and large parts of both flanking introns. The test strongly supports the monophyly of New World monkey DRB intron sequences. The phylogenies of introns 1 and 2 from DRB1*03-like and DRB3-like genes are congruent, but both are incongruent with the exon 2-based phylogeny. The matching of intron 1- and intron 2-based phylogenies with each other suggests that reciprocal recombination has not played a major role in exon 2 evolution. Statistical comparisons of exon 2 from different DRB1*03 and DRB3 lineages indicate that it was neither gene conversion (descent), nor chance, but molecular convergence that has shaped their characteristic motifs. The demonstration of convergence in anthropoid Mhc-DRB genes has implications for the classification, age, and mechanism of generation of DRB allelic lineages.

Amino Acid Sequence↗
PubMed1998

Astroglial interlaminar processes in the cerebral cortex of prosimians and Old World monkeys.

Previous observations have shown that astrocytes with interlaminar processes are present in the cerebral cortex of humans and New and Old World monkeys, but not in the rodent. The present report furthers the analysis of possible evolutionary aspects regarding the expression of such astroglial features. A comparison between young and adult Microcebus murinus, a prosimian, and Old World monkeys (Macaca mulatta and Papio hamadryas) is presented. Brain samples were processed for glial fibrillary acidic protein (GFAP), vimentin, MAP2 and SMI 311 immunocytochemistry, using different procedures. The cerebral cortex of adult Microcebus showed the presence of long astroglial processes, albeit reduced in number and length with respect to those observed in Old World monkeys. Macaca and Papio showed dense packing of such processes extending in most cortical regions to a depth of approximately 700 micrometers. Based on double immunolabelling for GFAP and MAP 2 antigens, the location and extent of these processes was shown to overlap with areas traversed by bundles and individual apical dendrites. Aged Old World specimens depicted an increased thickness of terminal portions of interlaminar processes, with increased morphological alterations. Comparisons made between the average thickness of the "brush" composed of interlaminar processes and the thickness of lamina I among the species analyzed disclosed an absence of relationship between them. This suggests that interlaminar processes do not represent cellular adaptations to the increase in thickness in superficial cortical laminae, but rather to some other evolutionary pressure. Since astroglial interlaminar processes are already present in a prosimian, although in a comparatively reduced manner, it is suggested that such processes underwent an early expression within the primate order, with increasing presence in more recent primate species.

Animals↗
PubMed2001

The poor quality of information about laparoscopy on the World Wide Web as indexed by popular search engines.

BACKGROUND: This study was undertaken to determine the quality of information on the Internet regarding laparoscopy. METHODS: Four popular World Wide Web search engines were used with the key word "laparoscopy." Advertisements, patient- or physician-directed information, and controversial material were noted. RESULTS: A total of 14,030 Web pages were found, but only 104 were unique Web sites. The majority of the sites were duplicate pages, subpages within a main Web page, or dead links. Twenty-eight of the 104 pages had a medical product for sale, 26 were patient-directed, 23 were written by a physician or group of physicians, and six represented corporations. The remaining 21 were "miscellaneous." The 46 pages containing educational material were critically reviewed. At least one of the senior authors found that 32 of the pages contained controversial or misleading statements. All of the three senior authors (LKN, NAO, GAF) independently agreed that 17 of the 46 pages contained controversial information. CONCLUSION: The World Wide Web is not a reliable source for patient or physician information about laparoscopy. Authenticating medical information on the World Wide Web is a difficult task, and no government or surgical society has taken the lead in regulating what is presented as fact on the World Wide Web.

Abstracting and Indexing↗
PubMed2004

The contribution to ophthalmic literature from different regions of the world.

PURPOSE: To compare the volume of ophthalmic literature from the developed and developing countries. METHODS: We performed a retrospective review of the five highest scoring impact factor journals in ophthalmology within the 3 year period 1998-2000 inclusive. Europe, North America, Australia, New Zealand and Japan were categorised as developed countries, all others were categorised as developing market economies. Correspondence, news articles and book reviews were excluded from our study. RESULTS: The developing world contributed to only 5.47% of the literature compared to the 92.19% from the developed world. The majority of the contribution to ophthalmic literature from the developing countries originated from Israel, S. America, China, Saudi Arabia, India, Singapore and Korea. 2.33% of literature was the result of collaborative research from the two groups. CONCLUSION: The developing countries account for 90.8% of world blindness, compared to 9.2% from the developed countries, there is therefore, an inverse relationship between the burden of world blindness and the contribution to the highest impact factor ophthalmic journals with the developed countries only contributing to 5% of this research.

Bibliometrics↗
PubMed2005

Catalytic activities of [GADV]-peptides. Formation and establishment of [GADV]-protein world for the emergence of life.

We have previously postulated a novel hypothesis for the origin of life, assuming that life on the earth originated from "[GADV]-protein world", not from the "RNA world" (see Ikehara's review, 2002). The [GADV]-protein world is constituted from peptides and proteins with random sequences of four amino acids (glycine [G], alanine [A], aspartic acid [D] and valine [V]), which accumulated by pseudo-replication of the [GADV]-proteins. To obtain evidence for the hypothesis, we produced [GADV]-peptides by repeated heat-drying of the amino acids for 30 cycles ([GADV]-P(30)) and examined whether the peptides have some catalytic activities or not. From the results, it was found that the [GADV]-P(30) can hydrolyze several kinds of chemical bonds in molecules, such as umbelliferyl-beta-D-galactoside, glycine-p-nitroanilide and bovine serum albumin. This suggests that [GADV]-P(30) could play an important role in the accumulation of [GADV]-proteins through pseudo-replication, leading to the emergence of life. We further show that [GADV]-octapaptides with random sequences, but containing no cyclic compounds as diketepiperazines, have catalytic activity, hydrolyzing peptide bonds in a natural protein, bovine serum albumin. The catalytic activity of the octapeptides was much higher than the [GADV]-P(30) produced through repeated heat-drying treatments. These results also support the [GADV]-protein-world hypothesis of the origin of life (see Ikehara's review, 2002). Possible steps for the emergence of life on the primitive earth are presented.

Alanine↗
PubMed1994

Sequence divergence, polymorphism and evolution of the middle-wave and long-wave visual pigment genes of great apes and Old World monkeys.

In man, the spectral shift between the middle-wave (MW) and long-wave (LW) visual pigments is largely achieved by amino acid substitution at two codons, both located in exon 5. A third amino acid site coded by exon 3 is polymorphic between pigments. We have studied the equivalent regions of the cone opsin genes in two members of the Hominidea (the gorilla, Gorilla gorilla and the chimpanzee, Pan troglodytes) and in three members of the Cercopithecoidea family of Old World primates (the diana monkey, Cercopithecus diana, the talapoin monkey, Miopithecus talapoin, and the crab-eating macaque, Macaca fascicularis). No variation in the codons that specify the amino acids involved in spectral tuning were found. We predict therefore that the MW and LW pigments of gorilla and chimpanzee have similar spectral characteristics to those of man. Multiple copies of the same opsin gene sequence were identified in the chimpanzee, talapoin and macaque and we also show that non-human Old World primates are similar to man in showing a bunching of polymorphic sites in exon 3. We discuss the ancestry of the separate MW and LW genes of Old World primates and the equivalent polymorphic gene of the marmoset, a New World primate.

Amino Acid Sequence↗
PubMed1995

Conservation among Old World Leishmania species of six physical linkage groups defined in Leishmania infantum small chromosomes.

We have characterised 49 DNA probes specific for each of the six smallest chromosomes in Leishmania infantum and have examined the allocation of these probes in the molecular karyotypes of the other Old World Leishmania species Leishmania donovani, Leishmania major, Leishmania tropica and Leishmania aethiopica. These 49 probes define 6 physical linkage groups in the molecular karyotypes of various strains of L. infantum. 40 of these probes hybridise in the other Old World Leishmania species and show a remarkably conserved linkage pattern. No interchromosomal exchange nor fusion could be detected. Thus, in spite of the chromosomal size polymorphisms, the general structure of the genome seems to be conserved in the six smallest chromosomes among Old World Leishmania species. This structural genomic homogeneity should be helpful for mapping studies of any Old World Leishmania genomes.

Animals↗
PubMed1993

Highland-lowland contrasts in the impact of Old World diseases in early colonial Ecuador.

Old World epidemics played a major role in the demographic collapse of native peoples after 1492. In estimating aboriginal populations it is often assumed that once introduced Old World diseases spread unhindered and their impact was uniform. This paper indicates that there were often marked regional differences in impact of Old World diseases which were related not only to environmental conditions, but also to the size and character of native societies. Drawing on research on the demographic history of early colonial Ecuador, it demonstrates that there were marked regional differences in levels of depopulation, particularly between the highlands and lowlands. It argues that the presence of tropical fevers provides an inadequate explanation for the higher levels of depopulation in the lowlands and goes on to suggest that regional differences in the impact of Old World diseases were influenced by the size of Indian populations, their settlement patterns, forms of subsistence, social organization and ideology. These affected not only disease mortality, but also the ability of native groups to recover.

Altitude↗
PubMed1996

Leprosy among the Limba: illness and healing in the context of world view.

The study analyzes the traditional beliefs and practices concerning leprosy of the Limba people of Sierra Leone. It shows that this dialectally diverse ethnic group has two views of leprosy and its cause, and two varieties of stigma associated with the disease. The Limba have abandoned their traditional treatments for leprosy in response to an effective leprosy control programme, but retained their traditional world view, including its definition of illness, which holds a person seriously ill only when he has severe pain or disability. Thus, they seek treatment from the programme, but often at a relatively advanced stage of the disease. The study shows that the Limba have reinterpreted the notion of 'germs' as introduced by medical workers, and that leprosy control workers have their own misunderstandings of Limba beliefs and practices. The study points the way to improved communication between leprosy workers and Limba patients by focusing on the points at which their views differ, and by identifying concepts within Limba world view that can be adapted by leprosy workers to help convey their message. The study emphasizes the importance of world view as a key to understanding patient attitudes and behaviour in developing countries, and to making valid cross-cultural comparisons, but notes that it can take years for an investigator to understand the world view of a particular culture. It argues that in short-term research projects there is an advantage to working with an anthropologist who has in-depth knowledge of the culture, but who may not be a specialist in medical anthropology.

Anthropology, Cultural↗
PubMed1986

Studies on the olfactory nervous system of the Old World monkey.

From the results of our electrophysiological and HRP studies in the old world monkey, multiple olfactory pathways have been clarified. The old world monkey has two neocortical olfactory areas, but no functional vomeronasal system. The response patterns to odors in various olfactory areas have also been studied. On the other hand, in the rabbit (Onoda and Iino, 1980) and dog (Onoda et al., 1981, 1982), which do have active vomeronasal systems, only one neocortical olfactory area was found. This important difference had already been indicated in three previous papers in which Takagi (1979, 1980, 1981) theorized that mammals can be divided into two groups according to their olfactory nervous mechanisms. One group includes old world monkeys, higher primates and man, and the other new world monkeys and lower mammals.

Animals↗
PubMed1993

World and regional populations.

Non-linear regression indicates that the logistic model provides excellent fits to world and continental human population data of the period 1950-1985. If the present logistic regime persists, the world population is likely to double in 47 years. Moreover, the eventual world population would be close to its final value of 23.8 billion by the year 2200, with about 11 billion in Asia and 10.5 billion in Africa. An approximately 95% confidence interval for the eventual world population is found to be between 11.9 and 35.7 billion. The logistic estimates of future populations are much higher than those considered most likely by the United Nations.

Humans↗
PubMed2005

A review of traffic-related air pollution exposure assessment studies in the developing world.

Exposure assessment studies in the developing world are important. Although recent years have seen an increasing number of traffic-related pollution exposure studies, exposure assessment data on this topic are still limited. Differences among measuring methods and a lack of strict quality control in carrying out exposure assessment make it difficult to generalize and compare findings between studies. In this article, exposure assessment studies carried out in the developing world on several traffic-related air pollutants are reviewed. These pollutants include particulate matter (PM), carbon monoxide (CO), nitrogen dioxide (NO(2)), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). In addition, it discusses advantages and disadvantages of various monitoring methods (ambient fixed-site monitoring, microenvironment monitoring, and personal exposure assessment using portable samplers) for these pollutants in exposure assessment studies. Also included in this paper is a brief introduction of standards for these pollutants in ambient air or in occupational settings established by the United States Environmental Protection Agency (USEPA), the United States Occupational Safety and Health Administration (OSHA) and the World Health Organization (WHO). The review ends with a summary of the limitations and gaps in recent studies and suggestions for future research in the developing world.

Air Pollutants↗